Search results for: sustainability management control
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 20411

Search results for: sustainability management control

701 Development of Earthquake and Typhoon Loss Models for Japan, Specifically Designed for Underwriting and Enterprise Risk Management Cycles

Authors: Nozar Kishi, Babak Kamrani, Filmon Habte

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Natural hazards such as earthquakes and tropical storms, are very frequent and highly destructive in Japan. Japan experiences, every year on average, more than 10 tropical cyclones that come within damaging reach, and earthquakes of moment magnitude 6 or greater. We have developed stochastic catastrophe models to address the risk associated with the entire suite of damaging events in Japan, for use by insurance, reinsurance, NGOs and governmental institutions. KCC’s (Karen Clark and Company) catastrophe models are procedures constituted of four modular segments: 1) stochastic events sets that would represent the statistics of the past events, hazard attenuation functions that could model the local intensity, vulnerability functions that would address the repair need for local buildings exposed to the hazard, and financial module addressing policy conditions that could estimates the losses incurring as result of. The events module is comprised of events (faults or tracks) with different intensities with corresponding probabilities. They are based on the same statistics as observed through the historical catalog. The hazard module delivers the hazard intensity (ground motion or wind speed) at location of each building. The vulnerability module provides library of damage functions that would relate the hazard intensity to repair need as percentage of the replacement value. The financial module reports the expected loss, given the payoff policies and regulations. We have divided Japan into regions with similar typhoon climatology, and earthquake micro-zones, within each the characteristics of events are similar enough for stochastic modeling. For each region, then, a set of stochastic events is developed that results in events with intensities corresponding to annual occurrence probabilities that are of interest to financial communities; such as 0.01, 0.004, etc. The intensities, corresponding to these probabilities (called CE, Characteristics Events) are selected through a superstratified sampling approach that is based on the primary uncertainty. Region specific hazard intensity attenuation functions followed by vulnerability models leads to estimation of repair costs. Extensive economic exposure model addresses all local construction and occupancy types, such as post-linter Shinand Okabe wood, as well as concrete confined in steel, SRC (Steel-Reinforced Concrete), high-rise.

Keywords: typhoon, earthquake, Japan, catastrophe modelling, stochastic modeling, stratified sampling, loss model, ERM

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700 The Role of High-Intensity Focused Ultrasound (HIFU) in the Treatment of Fibroadenomas: A Systematic Review

Authors: Ahmed Gonnah, Omar Masoud, Mohamed Abdel-Wahab, Ahmed ElMosalamy, Abdulrahman Al-Naseem

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Introduction: Fibroadenomas are solid, mobile, and non-tender benign breast lumps, with the highest prevalence amongst young women aged between 15 and 35. Symptoms can include discomfort, and they can become problematic, particularly when they enlarge, resulting in many referrals for biopsies, with fibroadenomas accounting for 30-75% of the cases. Diagnosis is based on triple assessment that involves a clinical examination, ultrasound imaging and mammography, as well as core needle biopsies. Current management includes observation for 6-12 months, with the indication of definitive surgery, in cases that are older than 35 years or with fibroadenoma persistence. Serious adverse effects of surgery might include nipple-areolar distortion, scarring and damage to the breast tissue, as well as the risks associated with surgery and anesthesia, making it a non-feasible option. Methods: A literature search was performed on the databases EMBASE. MEDLINE/PubMed, Google scholar and Ovid, for English language papers published between 1st of January 2000 and 17th of March 2021. A structured protocol was employed to devise a comprehensive search strategy with keywords and Boolean operators defined by the research question. The keywords used for the search were ‘HIFU’, ‘High-Intensity Focused Ultrasound’, ‘Fibroadenoma’, ‘Breast’, ‘Lesion’. This review was carried out in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Results: Recently, a thermal ablative technique, High Intensity Focused Ultrasound (HIFU), was found to be a safe, non-invasive, and technically successful alternative, having displayed promising outcomes in reducing the volume of fibroadenomas, pain experienced by patients, and the length of hospitalization. Quality of life improvement was also evidenced, exhibited by the disappearance of symptoms, and enhanced physical activity post-intervention, in addition to patients’ satisfaction with the cosmetic results and future recommendation of the procedure to other patients. Conclusion: Overall, HIFU is a well-tolerated treatment associated with a low risk of complications that can potentially include erythema, skin discoloration and bruising, with the majority of this self-resolving shortly after the procedure.

Keywords: ultrasound, HIFU, breast, efficacy, side effects, fibroadenoma

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699 Opportunities and Challenges in Midwifery Education: A Literature Review

Authors: Abeer M. Orabi

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Midwives are being seen as a key factor in returning birth care to a normal physiologic process that is woman-centered. On the other hand, more needs to be done to increase access for every woman to professional midwifery care. Because of the nature of the midwifery specialty, the magnitude of the effect that can result from a lack of knowledge if midwives make a mistake in their care has the potential to affect a large number of the birthing population. So, the development, running, and management of midwifery educational programs should follow international standards and come after a thorough community needs assessment. At the same time, the number of accredited midwifery educational programs needs to be increased so that larger numbers of midwives will be educated and qualified, as well as access to skilled midwifery care will be increased. Indeed, the selection of promising midwives is important for the successful completion of an educational program, achievement of the program goals, and retention of graduates in the field. Further, the number of schooled midwives in midwifery education programs, their background, and their experience constitute some concerns in the higher education industry. Basically, preceptors and clinical sites are major contributors to the midwifery education process, as educational programs rely on them to provide clinical practice opportunities. In this regard, the selection of clinical training sites should be based on certain criteria to ensure their readiness for the intended training experiences. After that, communication, collaboration, and liaison between teaching faculty and field staff should be maintained. However, the shortage of clinical preceptors and the massive reduction in the number of practicing midwives, in addition to unmanageable workloads, act as significant barriers to midwifery education. Moreover, the medicalized approach inherent in the hospital setting makes it difficult to practice the midwifery model of care, such as watchful waiting, non-interference in normal processes, and judicious use of interventions. Furthermore, creating a motivating study environment is crucial for avoiding unnecessary withdrawal and retention in any educational program. It is well understood that research is an essential component of any profession for achieving its optimal goal and providing a foundation and evidence for its practices, and midwifery is no exception. Midwives have been playing an important role in generating their own research. However, the selection of novel, researchable, and sustainable topics considering community health needs is also a challenge. In conclusion, ongoing education and research are the lifeblood of the midwifery profession to offer a highly competent and qualified workforce. However, many challenges are being faced, and barriers are hindering their improvement.

Keywords: barriers, challenges, midwifery education, educational programs

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698 A Foucauldian Analysis of Postcolonial Hybridity in a Kuwaiti Novel

Authors: Annette Louise Dupont

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Background and Introduction: Broadly defined, hybridity is a condition of racial and cultural ‘cross-pollination’ which arises as a result of contact between colonized and colonizer. It remains a highly contested concept in postcolonial studies as it is implicitly underpinned by colonial notions of ‘racial purity.’ While some postcolonial scholars argue that individuals exercise significant agency in the construction of their hybrid subjectivities, others underscore associated experiences of exclusion, marginalization, and alienation. Kuwait and the Philippines are among the most disparate of contemporary postcolonial states. While oil resources transformed the former British Mandate of Kuwait into one of the world’s richest countries, enduring poverty in the former US colony of the Philippines drives a global diaspora which produces multiple Filipino hybridities. Although more Filipinos work in the Arabian Gulf than in any other region of the world, scholarly and literary accounts of their experiences of hybridization in this region are relatively scarce when compared to those set in North America, Australia, Asia, and Europe. Study Aims and Significance: This paper aims to address this existing lacuna by investigating hybridity and other postcolonial themes in a novel by a Kuwaiti author which vividly portrays the lives of immigrants and citizens in Kuwait and which gives a rare voice and insight into the struggles of an Arab-Filipino and European-Filipina. Specifically, this paper explores the relationships between colonial discourses of ‘black’ and ‘white’ and postcolonial discourses pertaining to ‘brown’ Filipinos and ‘brown’ Arabs, in order to assess their impacts on the protagonists’ hybrid subjectivities. Methodology: Foucault’s notions of discourse not only provide a conceptual basis for analyzing the colonial ideology of Orientalism, but his theories related to the social exclusion of the ‘mad’ also elucidate the mechanisms by which power can operate to marginalize, alienate and subjectify the Other, therefore a Foucauldian lens is applied to the analysis of postcolonial themes and hybrid subjectivities portrayed in the novel. Findings: The study finds that Kuwaiti and Filipino discursive practices mirror those of former white colonialists and colonized black laborers and that these discursive practices combine with a former British colonial system of foreign labor sponsorship to create a form of governmentality in Kuwait which is based on exclusion and control. The novel’s rich social description and the reflections of the key protagonist and narrator suggest that such fiction has a significant role to play in highlighting the historical and cultural specificities of experiences of postcolonial hybridity in under-researched geographic, economic, social, and political settings. Whereas hybridity can appear abstract in scholarly accounts, the significance of literary accounts in which the lived experiences of hybrid protagonists are anchored to specific historical periods, places and discourses, is that contextual particularities are neither obscured nor dehistoricized. Conclusions: The application of Foucauldian theorizations of discourse, disciplinary, and biopower to the analysis of this Kuwaiti literary text serves to extend an understanding of the effects of contextually-specific discourses on hybrid Filipino subjectivities, as well as a knowledge of prevailing social dynamics in a little-researched postcolonial Arabian Gulf state.

Keywords: Filipino, Foucault, hybridity, Kuwait

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697 Nimart-trained Nurses' Perspectives Regarding Virally Unsuppressed Children HIV-positive on Antiretroviral Therapy and Missing Scheduled Clinic Visits: Mopani District, Limpopo Province

Authors: Linneth Nkateko Mabila, Patrick Hulisani Demana, Tebogo Maria Mothiba

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Background: Sustaining adherence to antiretroviral therapy (ART) over the long term by people, especially children living with Human-Immunodeficiency Virus (HIV), requires accurate and consistent monitoring, and this is a particular challenge for countries in sub-Saharan Africa. However, the regularity and punctuality in monthly antiretroviral treatment collections indicate medication adherence to a certain extent since it has been revealed to be a significant determinant of the outcome of ART. Aim: This study assessed and described the pattern of monthly antiretroviral treatment collections among a cohort of virally unsuppressed HIV-positive children initiated and managed on ART in the rural public clinics of Mopani District, Limpopo, and explored the nurses' perceptions and views of the findings. Methods: A facility-based mixed-methods study was conducted to assess the honoring of scheduled monthly treatment collection practices by a cohort of HIV-positive children under 15 years initiated and managed on ART by Nurse Initiated Management of Antiretroviral Treatment (NIMART)-trained professional nurses (PNs) from 01 January 2015 to 31 December 2015 in public PHC clinics of Mopani District Municipality. This was followed by the exploration of the nurses' perceptions and views regarding this issue to share their experiences and knowledge acquired through managing these children on ART. Results: From a total of 7105 analysable visits, only 44% (3134) were honored as scheduled, with 40% (2828) of children presenting to the clinics after the scheduled appointment date – they missed their appointments, and 11% (768) of treatment collections that took place before the scheduled appointment date. This finding was further confirmed by 90% (97) of the nurses, who reported that they have children who miss scheduled appointments in their public clinics. The primary reasons for children missing appointments were related to caregivers' forgetfulness and conflict between the school schedule and the dates of clinic visits. Conclusion: We confirmed a high prevalence of non-adherence to scheduled monthly ART collections and the existence of health system, social, and caregiver-related factors that threaten treatment adherence and proper clinical outcomes. These findings suggest an urgent need for intervention since non-adherence to ARV therapy can be life-threatening to the child and poses the danger of reduced life expectancy.

Keywords: antiretroviral therapy (art), nimart, virally unsuppressed children, missed appointments

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696 Land Use Influence on the 2014 Catastrophic Flood in the Northeast of Peninsular Malaysia

Authors: Zulkifli Yusop

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The severity of December 2014 flood on the east coast of Peninsular Malaysia has raised concern over the adequacy of existing land use practices and policies. This article assesses flood responses to selective logging, plantation establishment (oil palm and rubber) and their subsequent management regimes. The hydrological impacts were evaluated on two levels: on-site (mostly in the upstream) and off-site to reflect the cumulative impact at downstream. Results of experimental catchment studies suggest that on-site impact of flood could be kept to a minimum when selecting logging strictly adhere to the existing guidelines. However, increases in flood potential and sedimentation rate were observed with logging intensity and slope steepness. Forest conversion to plantation show the highest impacts. Except on the heavily compacted surfaces, the ground revegetation is usually rapid within two years upon the cessation of the logging operation. The hydrological impacts of plantation opening and replanting could be significantly reduced once the cover crop has fully established which normally takes between three to six months after sowing. However, as oil palms become taller and the canopy gets closer, the cover crop tends to die off due to light competition, and its protecting function gradually diminishes. The exposed soil is further compacted by harvesting machinery which subsequently leads to greater overland flow and erosion rates. As such, the hydrological properties of matured oil palm plantations are generally poorer than in young plantation. In hilly area, the undergrowth in rubber plantation is usually denser compared to under oil palm. The soil under rubber trees is also less compacted as latex collection is done manually. By considering the cumulative effects of land-use over space and time, selective logging seems to pose the least impact on flood potential, followed by planting rubber for latex, oil palm and Latex Timber Clone (LTC). The cumulative hydrological impact of LTC plantation is the most severe because of its shortest replanting rotation (12 to 15 years) compared to oil palm (25 years) and rubber for latex (35 years). Furthermore, the areas gazetted for LTC are mostly located on steeper slopes which are more susceptible to landslide and erosion. Forest has limited capability to store excess rainfall and is only effective in attenuating regular floods. Once the hydrologic storage is exceeded, the excess rainfall will appear as flood water. Therefore, for big floods, rainfall regime has a much bigger influence than land use.

Keywords: selective logging, plantation, extreme rainfall, debris flow

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695 The Influence of Absorptive Capacity on Process Innovation: An Exploratory Study in Seven Leading and Emerging Countries

Authors: Raphael M. Rettig, Tessa C. Flatten

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This empirical study answer calls for research on Absorptive Capacity and Process Innovation. Due to the fourth industrial revolution, manufacturing companies face the biggest disruption of their production processes since the rise of advanced manufacturing technologies in the last century. Therefore, process innovation will become a critical task to master in the future for many manufacturing firms around the world. The general ability of organizations to acquire, assimilate, transform, and exploit external knowledge, known as Absorptive Capacity, was proven to positively influence product innovation and is already conceptually associated with process innovation. The presented research provides empirical evidence for this influence. The findings are based on an empirical analysis of 732 companies from seven leading and emerging countries: Brazil, China, France, Germany, India, Japan, and the United States of America. The answers to the survey were collected in February and March 2018 and addressed senior- and top-level management with a focus on operations departments. The statistical analysis reveals the positive influence of potential and Realized Absorptive Capacity on successful process innovation taking the implementation of new digital manufacturing processes as an example. Potential Absorptive Capacity covering the acquisition and assimilation capabilities of an organization showed a significant positive influence (β = .304, p < .05) on digital manufacturing implementation success and therefore on process innovation. Realized Absorptive Capacity proved to have significant positive influence on process innovation as well (β = .461, p < .01). The presented study builds on prior conceptual work in the field of Absorptive Capacity and process innovation and contributes theoretically to ongoing research in two dimensions. First, the already conceptually associated influence of Absorptive Capacity on process innovation is backed by empirical evidence in a broad international context. Second, since Absorptive Capacity was measured with a focus on new product development, prior empirical research on Absorptive Capacity was tailored to the research and development departments of organizations. The results of this study highlight the importance of Absorptive Capacity as a capability in mechanical engineering and operations departments of organizations. The findings give managers an indication of the importance of implementing new innovative processes into their production system and fostering the right mindset of employees to identify new external knowledge. Through the ability to transform and exploit external knowledge, own production processes can be innovated successfully and therefore have a positive influence on firm performance and the competitive position of their organizations.

Keywords: absorptive capacity, digital manufacturing, dynamic capabilities, process innovation

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694 A Risk-Based Modeling Approach for Successful Adoption of CAATTs in Audits: An Exploratory Study Applied to Israeli Accountancy Firms

Authors: Alon Cohen, Jeffrey Kantor, Shalom Levy

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Technology adoption models are extensively used in the literature to explore drivers and inhibitors affecting the adoption of Computer Assisted Audit Techniques and Tools (CAATTs). Further studies from recent years suggested additional factors that may affect technology adoption by CPA firms. However, the adoption of CAATTs by financial auditors differs from the adoption of technologies in other industries. This is a result of the unique characteristics of the auditing process, which are expressed in the audit risk elements and the risk-based auditing approach, as encoded in the auditing standards. Since these audit risk factors are not part of the existing models that are used to explain technology adoption, these models do not fully correspond to the specific needs and requirements of the auditing domain. The overarching objective of this qualitative research is to fill the gap in the literature, which exists as a result of using generic technology adoption models. Followed by a pretest and based on semi-structured in-depth interviews with 16 Israeli CPA firms of different sizes, this study aims to reveal determinants related to audit risk factors that influence the adoption of CAATTs in audits and proposes a new modeling approach for the successful adoption of CAATTs. The findings emphasize several important aspects: (1) while large CPA firms developed their own inner guidelines to assess the audit risk components, other CPA firms do not follow a formal and validated methodology to evaluate these risks; (2) large firms incorporate a variety of CAATTs, including self-developed advanced tools. On the other hand, small and mid-sized CPA firms incorporate standard CAATTs and still need to catch up to better understand what CAATTs can offer and how they can contribute to the quality of the audit; (3) the top management of mid-sized and small CPA firms should be more proactive and updated about CAATTs capabilities and contributions to audits; and (4) All CPA firms consider professionalism as a major challenge that must be constantly managed to ensure an optimal CAATTs operation. The study extends the existing knowledge of CAATTs adoption by looking at it from a risk-based auditing approach. It suggests a new model for CAATTs adoption by incorporating influencing audit risk factors that auditors should examine when considering CAATTs adoption. Since the model can be used in various audited scenarios and supports strategic, risk-based decisions, it maximizes the great potential of CAATTs on the quality of the audits. The results and insights can be useful to CPA firms, internal auditors, CAATTs developers and regulators. Moreover, it may motivate audit standard-setters to issue updated guidelines regarding CAATTs adoption in audits.

Keywords: audit risk, CAATTs, financial auditing, information technology, technology adoption models

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693 Access of Refugees in Rural Areas to Regular Medication during COVID-19 Era: International Organization for Migration, Jordan Experience

Authors: Rasha Shoumar

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Background: Since the onset of the Syria crisis in 2011, Jordan has hosted many Syrian refugees, many of which are residing in urban and rural areas. Vulnerability of refugees has increased due to the COVID-19 pandemic, adding to their already existing challenge in access to medical services, rendering them vulnerable to the complications of untreated medical conditions and amplifying their risk for severe COVID-19 disease. To improve health outcomes and access to health care services in a COVID-19 context, IOM (The International Organization for Migration) provided health services including awareness raising, direct primary health care through mobile teams and referrals to secondary services were extended to the vulnerable populations of refugees. Method: 6 community health volunteers were trained and deployed to different governorates to provide COVID-19 and non-communicable disease awareness and collect data rated to non-communicable disease and access to medical health services. Primary health care services were extended to 7 governorates through a mobile medical team, providing medical management. The collected Data was reviewed and analyzed. Results: 2150 refugees in rural areas were reached out by community health volunteers, out of which 78 received their medications through the Ministry of Health, 121 received their medications through different non-governmental organizations, 665 patients couldn’t afford buying any medications, 1286 patients were occasionally buying their medications when they were able to afford it. 853 patients received medications and follow up through IOM mobile clinics, the most common conditions were hypertension, diabetes, hyperlipidemia, anemia, heart disease, thyroid disease, asthma, seizures, and psychiatric conditions. 709 of these patients had more than 3 of the comorbidities. Multiple cases were referred for secondary and tertiary lifesaving interventions. Conclusion: Non communicable diseases are highly prevalent among refugee population in Jordan, access to medical services have proven to be a challenge in rural areas especially during the COVID-19 era, many of the patients have multiple uncontrolled medical conditions placing them at risk for complications and risk for severe COVID-19 disease. Deployment of mobile clinics to rural areas plays an essential role in managing such medical conditions, thus improving the continuum of health care approach, physical and mental wellbeing of refugees and reducing the risk for severe COVID-19 disease among this group, taking us one step forward toward universal health access.

Keywords: COVID-19, refugees, mobile clinics, primary health care

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692 The Psychological Specification of Motivation of Managerial Activity

Authors: Laura Petrosyan

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The high and persistent working results are possible when people are interested in the results of the work. Motivation of working may be present as a psychological complicated phenomena, which determines person's behavior in working process. Researchers point out that working motivation is displayed in three correlated conditions. These are interest in outcomes of work, satisfaction with the work, and the third, is the level of devotion of employee. Solution of the problem of effective staff management depends on the development of workers' skills. Despite, above mentioned problem could be solved by the process of finding methods to induce the employees to the effective work. Motivation of the managerial activity aroused not only during the working process, but also before it starts. During education the future manager obtains many professional skills. However, the experience shows, that only professional skills are not enough for the effective work. Presently, one of the global educational problems is the development of motivation in professions. In psychological literature the fact is mentioned, that the motivation can be inside and outside. Outside motivation is active only at short time. Instead, inside motivation can be active during all process of the professional development. Hence, the motivation of managerial activity might be developed during the education. The future manager choose the profession being under some impression of personal qualities. Detection of future manager’s motivation will influence on the development of syllabuses. Moreover, use of the psychological methods could be evolved for preparing motivated managers. Conducted research has been done in the Public Administration Academy of the RA. The aim of research was to discover students' motivation of profession. 102 master students took part in the research from Public Administration Academy. In the research were used the following methods: method of identifying a person's motivation to succeed (T. Elers) and method of studying students’ motivation (T.E. Ilyin). First of the methods designed to explore a person's motivational orientation to get success represented by Hackhausen. The method gives the opportunity to reveal the level of motivation to success. In the second method separated three scales: i) Knowledge achievements, ii) Knowledge of the profession, iii) Get a diploma. The data obtained from these tests gave quantitative data. Aanalyses of our survey results exposes that within master students the high level have the average rates of knowledge achievements. The average rates of knowledge of the profession and geting a diploma not in high level. Furthermore, there are almost equal to each other. In the educational process The student acquiring skills not synthesize with the wield profession. Results show that specialists really view about profession not formulated yet.

Keywords: managerial activity, motivation, psychological complicated phenomena, working process, education the future manager

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691 Applicable Law to Intellectual and Industrial Property Agreements According to Turkish Private International Law and Rome I Regulation

Authors: Sema Cortoglu Koca

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Intellectual and industrial property rules, have a substantial effect on the sustainable development. Intellectual and industrial property rights, as temporary privileges over the products of intellectual activity, determine the supervision of information and technology. The level and scope of intellectual property protection thus influence the flow of technology between developed and developing countries. In addition, intellectual and industrial property rights are based on the notion of balance. Since they are time-limited rights, they reconcile private and public benefits. That is, intellectual and industrial property rights respond to both private interests and public interests by rewarding innovators and by promoting the dissemination of ideas, respectively. Intellectual and industrial property rights can, therefore, be a tool for sustainable development. If countries can balance their private and public interests according to their particular context and circumstances, they can ensure the intellectual and industrial property which promotes innovation and technology transfer relevant for them. People, enterprises and countries who need technology, can transfer developed technology which is acquired by people, enterprises and countries so as to decrease their technological necessity and improve their technology. Because of the significance of intellectual and industrial property rights on the technology transfer law as mentioned above, this paper is confined to intellectual and industrial property agreements especially technology transfer contracts. These are license contract, know-how contract, franchise agreement, joint venture agreement, management agreement, research and development agreement. In Turkey, technology transfer law is still a developing subject. For developing countries, technology transfer regulations are very important for their private international law because these countries do not know which technology transfer law is applicable when conflicts arise. In most technology transfer contracts having international elements, the parties choose a law to govern their contracts. Where the parties do not choose a law, either expressly or impliedly, and matters which is not excluded in party autonomy, the court has to determine the applicable law to contracts in a matter of capacity, material, the formal and essential validity of contracts. For determining the proper law of technology transfer contracts, it is tried to build a rule for applying all technology transfer contracts. This paper is confined to the applicable law to intellectual and industrial property agreements according to ‘5718 Turkish Act on Private International Law and Civil Procedure’ and ‘Regulation (EC) No 593/2008 of the European Parliament and of the Council of 17 June 2008 on the law applicable to contractual obligations (Rome I)’. Like these complex contracts, to find a rule can be really difficult. We can arrange technology transfer contracts in groups, and we can determine the rule and connecting factors to these groups. For the contracts which are not included in these groups, we can determine a special rule considering the characteristics of the contract.

Keywords: intellectual and industrial property agreements, Rome I regulation, technology transfer, Turkish act on private international law and civil procedure

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690 Study of the Biological Activity of a Ganglioside-Containing Drug (Cronassil) in an Experimental Model of Multiple Sclerosis

Authors: Hasmik V. Zanginyan, Gayane S. Ghazaryan, Laura M. Hovsepyan

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Experimental autoimmune encephalomyelitis (EAE) is an inflammatory demyelinating disease of the central nervous system that is induced in laboratory animals by developing an immune response against myelin epitopes. The typical clinical course is ascending palsy, which correlates with inflammation and tissue damage in the thoracolumbar spinal cord, although the optic nerves and brain (especially the subpial white matter and brainstem) are also often affected. With multiple sclerosis, there is a violation of lipid metabolism in myelin. When membrane lipids (glycosphingolipids, phospholipids) are disturbed, metabolites not only play a structural role in membranes but are also sources of secondary mediators that transmit multiple cellular signals. The purpose of this study was to investigate the effect of ganglioside as a therapeutic agent in experimental multiple sclerosis. The biological activity of a ganglioside-containing medicinal preparation (Cronassial) was evaluated in an experimental model of multiple sclerosis in laboratory animals. An experimental model of multiple sclerosis in rats was obtained by immunization with myelin basic protein (MBP), as well as homogenization of the spinal cord or brain. EAE was induced by administering a mixture of an encephalitogenic mixture (EGM) with Complete Freund’s Adjuvant. Mitochondrial fraction was isolated in a medium containing 0,25 M saccharose and 0, 01 M tris buffer, pH - 7,4, by a method of differential centrifugation on a K-24 centrifuge. Glutathione peroxidase activity was assessed by reduction reactions of hydrogen peroxide (H₂O₂) and lipid hydroperoxides (ROOH) in the presence of GSH. LPO activity was assessed by the amount of malondialdehyde (MDA) in the total homogenate and mitochondrial fraction of the spinal cord and brain of control and experimental autoimmune encephalomyelitis rats. MDA was assessed by a reaction with Thiobarbituric acid. For statistical data analysis on PNP, SPSS (Statistical Package for Social Science) package was used. The nature of the distribution of the obtained data was determined by the Kolmogorov-Smirnov criterion. The comparative analysis was performed using a nonparametric Mann-Whitney test. The differences were statistically significant when р ≤ 0,05 or р ≤ 0,01. Correlational analysis was conducted using a nonparametric Spearman test. In the work, refrigeratory centrifuge, spectrophotometer LKB Biochrom ULTROSPECII (Sweden), pH-meter PL-600 mrc (Israel), guanosine, and ATP (Sigma). The study of the process of lipid peroxidation in the total homogenate of the brain and spinal cord in experimental animals revealed an increase in the content of malonic dialdehyde. When applied, Cronassial observed normalization of lipid peroxidation processes. Reactive oxygen species, causing lipid peroxidation processes, can be toxic both for neurons and for oligodendrocytes that form myelin, causing a violation of their lipid composition. The high content of lipids in the brain and the uniqueness of their structure determines the nature of the development of LPO processes. The lipid layer of cellular and intracellular membranes performs two main functions -barrier and matrix (structural). Damage to the barrier leads to dysregulation of intracellular processes and severe disorders of cellular functions.

Keywords: experimental autoimmune encephalomyelitis, multiple sclerosis, neuroinflammation, therapy

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689 Integrating the Modbus SCADA Communication Protocol with Elliptic Curve Cryptography

Authors: Despoina Chochtoula, Aristidis Ilias, Yannis Stamatiou

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Modbus is a protocol that enables the communication among devices which are connected to the same network. This protocol is, often, deployed in connecting sensor and monitoring units to central supervisory servers in Supervisory Control and Data Acquisition, or SCADA, systems. These systems monitor critical infrastructures, such as factories, power generation stations, nuclear power reactors etc. in order to detect malfunctions and ignite alerts and corrective actions. However, due to their criticality, SCADA systems are vulnerable to attacks that range from simple eavesdropping on operation parameters, exchanged messages, and valuable infrastructure information to malicious modification of vital infrastructure data towards infliction of damage. Thus, the SCADA research community has been active over strengthening SCADA systems with suitable data protection mechanisms based, to a large extend, on cryptographic methods for data encryption, device authentication, and message integrity protection. However, due to the limited computation power of many SCADA sensor and embedded devices, the usual public key cryptographic methods are not appropriate due to their high computational requirements. As an alternative, Elliptic Curve Cryptography has been proposed, which requires smaller key sizes and, thus, less demanding cryptographic operations. Until now, however, no such implementation has been proposed in the SCADA literature, to the best of our knowledge. In order to fill this gap, our methodology was focused on integrating Modbus, a frequently used SCADA communication protocol, with Elliptic Curve based cryptography and develop a server/client application to demonstrate the proof of concept. For the implementation we deployed two C language libraries, which were suitably modify in order to be successfully integrated: libmodbus (https://github.com/stephane/libmodbus) and ecc-lib https://www.ceid.upatras.gr/webpages/faculty/zaro/software/ecc-lib/). The first library provides a C implementation of the Modbus/TCP protocol while the second one offers the functionality to develop cryptographic protocols based on Elliptic Curve Cryptography. These two libraries were combined, after suitable modifications and enhancements, in order to give a modified version of the Modbus/TCP protocol focusing on the security of the data exchanged among the devices and the supervisory servers. The mechanisms we implemented include key generation, key exchange/sharing, message authentication, data integrity check, and encryption/decryption of data. The key generation and key exchange protocols were implemented with the use of Elliptic Curve Cryptography primitives. The keys established by each device are saved in their local memory and are retained during the whole communication session and are used in encrypting and decrypting exchanged messages as well as certifying entities and the integrity of the messages. Finally, the modified library was compiled for the Android environment in order to run the server application as an Android app. The client program runs on a regular computer. The communication between these two entities is an example of the successful establishment of an Elliptic Curve Cryptography based, secure Modbus wireless communication session between a portable device acting as a supervisor station and a monitoring computer. Our first performance measurements are, also, very promising and demonstrate the feasibility of embedding Elliptic Curve Cryptography into SCADA systems, filling in a gap in the relevant scientific literature.

Keywords: elliptic curve cryptography, ICT security, modbus protocol, SCADA, TCP/IP protocol

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688 Enhancing Photocatalytic Activity of Oxygen Vacancies-Rich Tungsten Trioxide (WO₃) for Sustainable Energy Conversion and Water Purification

Authors: Satam Alotibi, Osama A. Hussein, Aziz H. Al-Shaibani, Nawaf A. Al-Aqeel, Abdellah Kaiba, Fatehia S. Alhakami, Mohammed Alyami, Talal F. Qahtan

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The demand for sustainable and efficient energy conversion using solar energy has grown rapidly in recent years. In this pursuit, solar-to-chemical conversion has emerged as a promising approach, with oxygen vacancies-rich tungsten trioxide (WO₃) playing a crucial role. This study presents a method for synthesizing oxygen vacancies-rich WO3, resulting in a significant enhancement of its photocatalytic activity, representing a significant step towards sustainable energy solutions. Experimental results underscore the importance of oxygen vacancies in modifying the properties of WO₃. These vacancies introduce additional energy states within the material, leading to a reduction in the bandgap, increased light absorption, and acting as electron traps, thereby reducing emissions. Our focus lies in developing oxygen vacancies-rich WO₃, which demonstrates unparalleled potential for improved photocatalytic applications. The effectiveness of oxygen vacancies-rich WO₃ in solar-to-chemical conversion was showcased through rigorous assessments of its photocatalytic degradation performance. Sunlight irradiation was employed to evaluate the material's effectiveness in degrading organic pollutants in wastewater. The results unequivocally demonstrate the superior photocatalytic performance of oxygen vacancies-rich WO₃ compared to conventional WO₃ nanomaterials, establishing its efficacy in sustainable and efficient energy conversion. Furthermore, the synthesized material is utilized to fabricate films, which are subsequently employed in immobilized WO₃ and oxygen vacancies-rich WO₃ reactors for water purification under natural sunlight irradiation. This application offers a sustainable and efficient solution for water treatment, harnessing solar energy for effective decontamination. In addition to investigating the photocatalytic capabilities, we extensively analyze the structural and chemical properties of the synthesized material. The synthesis process involves in situ thermal reduction of WO₃ nano-powder in a nitrogen environment, meticulously monitored using thermogravimetric analysis (TGA) to ensure precise control over the synthesis of oxygen vacancies-rich WO₃. Comprehensive characterization techniques such as UV-Vis spectroscopy, X-ray photoelectron spectroscopy (XPS), FTIR, Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and selected area electron diffraction (SAED) provide deep insights into the material's optical properties, chemical composition, elemental states, structure, surface properties, and crystalline structure. This study represents a significant advancement in sustainable energy conversion through solar-to-chemical processes and water purification. By harnessing the unique properties of oxygen vacancies-rich WO₃, we not only enhance our understanding of energy conversion mechanisms but also pave the way for the development of highly efficient and environmentally friendly photocatalytic materials. The application of this material in water purification demonstrates its versatility and potential to address critical environmental challenges. These findings bring us closer to a sustainable energy future and cleaner water resources, laying a solid foundation for a more sustainable planet.

Keywords: sustainable energy conversion, solar-to-chemical conversion, oxygen vacancies-rich tungsten trioxide (WO₃), photocatalytic activity enhancement, water purification

Procedia PDF Downloads 65
687 Emergency Surgery in the Elderly, What Particularities

Authors: Mekroud Amel

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Introduction The rate of use by the elderly of emergency departments, operating rooms and intensive care units has increased worldwide. Emergency surgery is a context where evaluation is often insufficient, with incomplete information gathering. The aim of this work is to shed light on the frequent use of emergency surgeries by the elderly and their characteristics, as well as on the lack of geriatric assessment scores in the emergency room. Material : Prospective, observational and descriptive, monocentric study. Patients aged 65 and over, admitted for emergency surgery in the operating room, were counted. Emergency operating room including visceral surgery, urology, traumatology and neurosurgery. Parameters studied: Patient characteristics, degree of autonomy, type of surgical pathology, operative management times, preoperative evaluation, postoperative outcome Results : 192 patients were identified over 12 months, from 09.01.2017 to 08.31.2018 Age from 65 to 101 years, 79.81 years +/- 8.38. With predominance of the age group between [65-75 years] 41.1% Female predominance, Sexratio = 0.81 Elderly subjects with total motor autonomy are in the majority at 57.8% Subjects without pathological ATCD represent 12.5% of cases Those who are on only one type of medication or without any treatment are at 36.9% Discussion : The emergency operative care of the elderly patient for a surgical or traumatological pathology is characterized by many specificities linked first to the emergency context, where the evaluation is often insufficient, besides the fact that the elderly patient has particularities requiring reception in centers with experience in the care of this category of patient, or, failing that, a center which uses the minimum of geriatric evaluation scores which are simplified for the emergency departments. In our hospital, we have not yet made this evaluation routine in the emergency room and this delay in the introduction of these scores can be directly attributed to the covid 19 pandemic. Besides the standard preoperative assessment, only 43.2% of patients were assessed in the preoperative period by an anesthesiologist. Traumatological emergencies come first 68.2% followed by visceral emergencies 19.2% (including proctological, urological emergencies), neurosurgical emergencies 7.8% and finally peripheral emergency surgery all acts combined 4.7%. Hospital stay at 9.6 +/- 16.8 days, average operability time of 4.5 +/- 3 days. Death rate at 7.29% Conclusion This work has demonstrated the major impact of emergency surgery, which remains curable for the most part, on the elderly patient despite total motor and cognitive autonomy preoperatively. The improvement of the preoperative evaluation, the reduction of the operating time and enhanced recovery after surgery, with personalized protocols, are the only guarantee for the resumption of preoperative autonomy in these patients.

Keywords: emergency surgery, elderly patients, preoperative geriatric scores, curable emergency surgical pathologies

Procedia PDF Downloads 75
686 The Residential Subdivision under the Influence of the Unfinished Densification, Case Study for Subdivisions in Setif, Algeria

Authors: Lacheheb Dhia Eddine Zakaria, Ballout Amor

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Today, it is necessary to be thrifty for its planet, on one hand the space being a rare, nonrenewable resource, and on the other hand the ecological, economic and social cost of the urban sprawl. It is commonly asserted that the promotion of a more compact and dense city has a positive effect in terms of public costs of investment, functioning and costs for the citizens and the users of the city. It is clear that the modes urban development management have to evolve profoundly, in particular towards a densification favourable to the raising of the urban quality through an ideal urban density on the scale of the individual housing estate. The lot as an individual housing estate was adopted as an alternative development model to the collective housing, thought in an anthropocentric perspective to emerge as a quality model where the density plays an important role, by being included in operations of a global coherence, in an optimal organization without forgetting the main importance of the deadlines of construction and the finalization of the works. The image of eternal construction site inflicted to our cities explains the renewed interest for the application of the regulatory framework and the completion of these limited operations without global coherence, which are summed up in our case to a ground cut in plots of land, sold then built independently without being finished, and support the relevance of the essential question of the improvement of the outside aspect bound to the appearance which can be revealed as a so important factor for a better use and a better acceptance of its housing environment, that the ratio of a number of houses on a plot of land or the number of square meters by house. To demonstrate the impact of the completion degree of the subdivision dwellings, roads system and urban public utilities on the density or the densification and therefore on the urban quality, we studied two residential subdivisions, the private subdivision Sellam and the subdivision El Imane with a common situation, and a different land surface, density and cutting, being occupied by various social classes, with different needs and different household average size. The approach of this work is based on the typo morphological analysis to reveal the differences in the degrees of completions of the subdivision’s built environment and on the investigation, by a household’s survey, to demonstrate importance of the degree of completion and to reveal the conditions of qualitative densification favourable and convenient to a better subdivision’s appropriation.

Keywords: subdivision, degree of completion, densification, urban quality

Procedia PDF Downloads 370
685 Osseointegration Outcomes Following Amputee Lengthening

Authors: Jason Hoellwarth, Atiya Oomatia, Anuj Chavan, Kevin Tetsworth, Munjed Al Muderis

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Introduction: Percutaneous EndoProsthetic Osseointegration for Limbs (PEPOL) facilitates improved quality of life (QOL) and objective mobility for most amputees discontent with their traditional socket prosthesis (TSP) experience. Some amputees desiring PEPOL have residual bone much shorter than the currently marketed press-fit implant lengths of 14-16 cm, potentially a risk for failure to integrate. We report on the techniques used, complications experienced, the management of those complications, and the overall mobility outcomes of seven patients who had femur distraction osteogenesis (DO) with a Freedom nail followed by PEPOL. Method: Retrospective evaluation of a prospectively maintained database identified nine patients (5 females) who had transfemoral DO in preparation for PEPOL with two years of follow-up after PEPOL. Six patients had traumatic causes of amputation, one had perinatal complications, one was performed to manage necrotizing fasciitis and one was performed as a result of osteosarcoma. Result: The average age at which DO commenced was 39.4±15.9 years, and seven patients had their amputation more than ten years prior (average 25.5±18.8 years). The residual femurs, on average, started at 102.2±39.7 mm and were lengthened 58.1±20.7 mm, 98±45% of the goal (99±161% of the original bone length). Five patients (56%) had a complication requiring additional surgery: four events of inadequate regeneration were managed with continued lengthening to the desired goal followed by autograft placement harvested from contralateral femur reaming; one patient had the cerclage wires break, which required operative replacement. All patients had osseointegration performed at 355±123 days after the initial lengthening nail surgery. One patient had K-level >2 before DO, at a mean of 3.4±0.6 (2.6-4.4) years following osseointegration. Six patients had K-level >2. The 6-Minute Walk Test remained unchanged (267±56 vs. 308 ± 117 meters). Patient self-rating of prosthesis function, problems, and amputee situation did not significantly change from before DO to after osseointegration. Six patients required additional surgery following osseointegration: six to remove fixation plates placed to maintain distraction osteogenesis length at osseointegration; two required irritation and debridement for infection. Conclusion: Extremely short residual femurs, which make TSP use troublesome, can be lengthened with externally controlled telescoping nails and successfully achieve osseointegration. However, it is imperative to counsel patients that additional surgery to address inadequate regeneration or to remove painful hardware used to maintain fixation may be necessary. This may improve the amputee’s expectations before beginning a potentially arduous process.

Keywords: osseointegration, limb lengthening, quality of life, amputation

Procedia PDF Downloads 68
684 Patient Agitation and Violence in Medical-Surgical Settings at BronxCare Hospital, Before and During COVID-19 Pandemic; A Retrospective Chart Review

Authors: Soroush Pakniyat-Jahromi, Jessica Bucciarelli, Souparno Mitra, Neda Motamedi, Ralph Amazan, Samuel Rothman, Jose Tiburcio, Douglas Reich, Vicente Liz

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Violence is defined as an act of physical force that is intended to cause harm and may lead to physical and/or psychological damage. Violence toward healthcare workers (HCWs) is more common in psychiatric settings, emergency departments, and nursing homes; however, healthcare workers in medical setting are not spared from such events. Workplace violence has a huge burden in the healthcare industry and has a major impact on the physical and mental wellbeing of staff. The purpose of this study is to compare the prevalence of patient agitation and violence in medical-surgical settings in BronxCare Hospital (BCH) Bronx, New York, one year before and during the COVID-19 pandemic. Data collection occurred between June 2021 and August 2021, while the sampling time was from 2019 to 2021. The data were separated into two separate time categories: pre-COVID-19 (03/2019-03/2020) and COVID-19 (03/2020-03/2021). We created frequency tables for 19 variables. We used a chi-square test to determine a variable's statistical significance. We tested all variables against “restraint type”, determining if a patient was violent or became violent enough to restrain. The restraint types were “chemical”, “physical”, or both. This analysis was also used to determine if there was a statistical difference between the pre-COVID-19 and COVID-19 timeframes. Our data shows that there was an increase in incidents of violence in COVID-19 era (03/2020-03/2021), with total of 194 (62.8%) reported events, compared to pre COVID-19 era (03/2019-03/2020) with 115 (37.2%) events (p: 0.01). Our final analysis, completed using a chi-square test, determined the difference in violence in patients between pre-COVID-19 and COVID-19 era. We then tested the violence marker against restraint type. The result was statistically significant (p: 0.01). This is the first paper to systematically review the prevalence of violence in medical-surgical units in a hospital in New York, pre COVID-19 and during the COVID-19 era. Our data is in line with the global trend of increased prevalence of patient agitation and violence in medical settings during the COVID-19 pandemic. Violence and its management is a challenge in healthcare settings, and the COVID-19 pandemic has brought to bear a complexity of circumstances, which may have increased its incidence. It is important to identify and teach healthcare workers the best preventive approaches in dealing with patient agitation, to decrease the number of restraints in medical settings, and to create a less restrictive environment to deliver care.

Keywords: COVID-19 pandemic, patient agitation, restraints, violence

Procedia PDF Downloads 142
683 Examining the Behavioral, Hygienic and Expectational Changes in Adolescents and Young Women during COVID-19 Quarantine in Colombia

Authors: Rocio Murad, Marcela Sanchez, Mariana Calderon Jaramillo, Danny Rivera, Angela Cifuentes, Daniela Roldán, Juan Carlos Rivillas

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Women and girls have specific health needs, but during health pandemics such as COVID19 they are less likely to have access to quality essential health information, commodities and services, or insurance coverage for routine and catastrophic health expenses, especially in rural and marginalized communities. This is compounded by multiple or intersecting inequalities, such as ethnicity, socioeconomic status, disability, age, geographic location, and sexual orientation, among others. Despite concerted collective action, there is a lack of information on the situation of women, adolescents and youth, including gender inequalities exacerbated by the pandemic. Much more needs to be done to amplify the lived realities of women and adolescents in global and national advocacy and policy responses. The COVID 19 pandemic reflects the need for systematic advocacy policies based on the lived experiences of women and adolescents, underpinned by human rights. This research is part of the initiative of Profamilia Association (Solidarity Study), and its objective is twofold: i) to analyze the behavioral changes and immediate expectations of Colombians during the stage of relaxation of the confinement measures decreed by the national government; and ii) to identify the needs, experiences and resilient practices of adolescents and young women during the COVID-19 crisis in Colombia. Descriptive analysis of data collected by Profamilia through the Solidaridad study, an exploratory cross-sectional descriptive study that used subnational level data from a nonprobabilistic sample survey conducted to 1735 adults, between September 01 and 11, 2020. Interviews were conducted with key stakeholders about their experiences during COVID19, under three key axes: i) main challenges for adolescents and young women; ii) examples of what has worked well in responding to the challenge; and iii) how/what services are/should be provided during COVID-19 (and beyond) to address the challenge. Interviewees were selected based on prior mapping of social groups of interest. In total, 23 adolescents and young women participated in the interviews. The results show that people adopted behavioral changes such as wearing masks, avoiding people with symptoms, and reducing mobility, but there was also a doubling of concerns for many reasons, from effects on mental health, sexual health, and unattended reproductive health to the burden of care and working at home. The favorable perception that people had at the beginning of the quarantine about the response and actions of the national and local government to control Covid-19 decreased over the course of the quarantine. The challenges and needs of adolescents and young women were highlighted during the most restrictive measures to contain the COVID-19 pandemic, which resulted in disruptions to daily activities, education and work, as well as restrictions to mobility and social interaction. Concerns raised by participants included: impact on mental health and wellbeing due to disruption of daily life; limitations in access to formal and informal education; food insecurity; migration; loss of livelihoods; lack of access to health information and services; limitations to sexual and reproductive health and rights; insecurity problems; and problems in communication and treatment among household members.

Keywords: COVID-19, changes in behavior, adolescents, women

Procedia PDF Downloads 105
682 Impact of Air Pressure and Outlet Temperature on Physicochemical and Functional Properties of Spray-dried Skim Milk Powder

Authors: Adeline Meriaux, Claire Gaiani, Jennifer Burgain, Frantz Fournier, Lionel Muniglia, Jérémy Petit

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Spray-drying process is widely used for the production of dairy powders for food and pharmaceuticals industries. It involves the atomization of a liquid feed into fine droplets, which are subsequently dried through contact with a hot air flow. The resulting powders permit transportation cost reduction and shelf life increase but can also exhibit various interesting functionalities (flowability, solubility, protein modification or acid gelation), depending on operating conditions and milk composition. Indeed, particles porosity, surface composition, lactose crystallization, protein denaturation, protein association or crust formation may change. Links between spray-drying conditions and physicochemical and functional properties of powders were investigated by a design of experiment methodology and analyzed by principal component analysis. Quadratic models were developed, and multicriteria optimization was carried out by the use of genetic algorithm. At the time of abstract submission, verification spray-drying trials are ongoing. To perform experiments, milk from dairy farm was collected, skimmed, froze and spray-dried at different air pressure (between 1 and 3 bars) and outlet temperature (between 75 and 95 °C). Dry matter, minerals content and proteins content were determined by standard method. Solubility index, absorption index and hygroscopicity were determined by method found in literature. Particle size distribution were obtained by laser diffraction granulometry. Location of the powder color in the Cielab color space and water activity were characterized by a colorimeter and an aw-value meter, respectively. Flow properties were characterized with FT4 powder rheometer; in particular compressibility and shearing test were performed. Air pressure and outlet temperature are key factors that directly impact the drying kinetics and powder characteristics during spray-drying process. It was shown that the air pressure affects the particle size distribution by impacting the size of droplet exiting the nozzle. Moreover, small particles lead to more cohesive powder and less saturated color of powders. Higher outlet temperature results in lower moisture level particles which are less sticky and can explain a spray-drying yield increase and the higher cohesiveness; it also leads to particle with low water activity because of the intense evaporation rate. However, it induces a high hygroscopicity, thus, powders tend to get wet rapidly if they are not well stored. On the other hand, high temperature provokes a decrease of native serum proteins which is positively correlated to gelation properties (gel point and firmness). Partial denaturation of serum proteins can improve functional properties of powder. The control of air pressure and outlet temperature during the spray-drying process significantly affects the physicochemical and functional properties of powder. This study permitted to better understand the links between physicochemical and functional properties of powder, to identify correlations between air pressure and outlet temperature. Therefore, mathematical models have been developed and the use of genetic algorithm will allow the optimization of powder functionalities.

Keywords: dairy powders, spray-drying, powders functionalities, design of experiment

Procedia PDF Downloads 85
681 Chemicals to Remove and Prevent Biofilm

Authors: Cynthia K. Burzell

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Aequor's Founder, a Marine and Medical Microbiologist, discovered novel, non-toxic chemicals in the ocean that uniquely remove biofilm in minutes and prevent its formation for days. These chemicals and over 70 synthesized analogs that Aequor developed can replace thousands of toxic biocides used in consumer and industrial products and, as new drug candidates, kill biofilm-forming bacteria and fungi Superbugs -the antimicrobial-resistant (AMR) pathogens for which there is no cure. Cynthia Burzell, PhD., is a Marine and Medical Microbiologist studying natural mechanisms that inhibit biofilm formation on surfaces in contact with water. In 2002, she discovered a new genus and several new species of marine microbes that produce small molecules that remove biofilm in minutes and prevent its formation for days. The molecules include new antimicrobials that can replace thousands of toxic biocides used in consumer and industrial products and can be developed into new drug candidates to kill the biofilm-forming bacteria and fungi -- including the antimicrobial-resistant (AMR) Superbugs for which there is no cure. Today, Aequor has over 70 chemicals that are divided into categories: (1) Novel natural chemicals. Lonza validated that the primary natural chemical removed biofilm in minutes and stated: "Nothing else known can do this at non-toxic doses." (2) Specialty chemicals. 25 of these structural analogs are already approved under the U.S. Environmental Protection Agency (EPA)'s Toxic Substances Control Act, certified as "green" and available for immediate sale. These have been validated for the following agro-industrial verticals: (a) Surface cleaners: The U.S. Department of Agriculture validated that low concentrations of Aequor's formulations provide deep cleaning of inert, nano and organic surfaces and materials; (b) Water treatments: NASA validated that one dose of Aequor's treatment in the International Space Station's water reuse/recycling system lasted 15 months without replenishment. DOE validated that our treatments lower energy consumption by over 10% in buildings and industrial processes. Future validations include pilot projects with the EPA to test efficacy in hospital plumbing systems. (c) Algae cultivation and yeast fermentation: The U.S. Department of Energy (DOE) validated that Aequor's treatment boosted biomass of renewable feedstocks by 40% in half the time -- increasing the profitability of biofuels and biobased co-products. DOE also validated increased yields and crop protection of algae under cultivation in open ponds. A private oil and gas company validated decontamination of oilfield water. (3) New structural analogs. These kill Gram-negative and Gram-positive bacteria and fungi alone, in combinations with each other, and in combination with low doses of existing, ineffective antibiotics (including Penicillin), "potentiating" them to kill AMR pathogens at doses too low to trigger resistance. Both the U.S. National Institutes for Health (NIH) and Department of Defense (DOD) has executed contracts with Aequor to provide the pre-clinical trials needed for these new drug candidates to enter the regulatory approval pipelines. Aequor seeks partners/licensees to commercialize its specialty chemicals and support to evaluate the optimal methods to scale-up of several new structural analogs via activity-guided fractionation and/or biosynthesis in order to initiate the NIH and DOD pre-clinical trials.

Keywords: biofilm, potentiation, prevention, removal

Procedia PDF Downloads 96
680 Comparative Study on the Influence of Different Drugs against Aluminium- Induced Nephrotoxicity and Hepatotoxicity in Rats

Authors: Azza A. Ali, Toqa M. Elnahhas, Abeer I. Abd El-Fattah, Mona M. Kamal, Karema Abu-Elfotuh

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Background: Environmental pollution with the different aluminium (Al) containing compounds especially those in industrial waste water exposes people to higher than normal levels of Al that represents an environmental risk factor. Cosmetics, Al ware, and containers are also sources of Al besides some foods and food additives. In addition to its known neurotoxicity, Al affects other body structures like skeletal system, blood cells, liver and kidney. Accumulation of Al in kidney and liver induces nephrotoxicity and hepatotoxicity. Coenzyme Q10 (CoQ10) is a pseudo-vitamin substance primarily present in the mitochondria. It is a powerful antioxidant and acts as radical scavenger. Wheat grass is a natural product that contains carbohydrates, proteins, vitamins, minerals, enzymes and has antioxidant, anti-inflammatory, anticancer and cardiovascular protection activities. Cocoa is an excellent source of iron, potent antioxidants and can protect against many diseases. Vinpocetine is an antioxidant and anti inflammatory while zinc is an essential trace element involved in cell division and its deficiency is observed in many types of liver disease. Objective: To evaluate and compare the potency of different drugs (CoQ10, wheatgrass, cocoa, vinpocetine and zinc) against nephro- and hepato-toxicity induced by Al in rats. Methods: Rats were divided to seven groups and received daily for three weeks either saline for control group or AlCl3 (70 mg/kg, IP) for Al-toxicity model groups. Five groups of Al-toxicity model (treated groups) were orally received together with Al each of the following; CoQ10 (200mg/kg), wheat grass (100mg/kg), cocoa powder (24mg/kg), vinpocetine (20mg/kg) or zinc (32mg/kg). Biochemical changes in the serum level of Alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), lactate deshydrogenase (LDH) as well as total bilirubin, lipids, cholesterol, triglycerides, glucose, proteins, creatinine and urea were measured. Liver and kidney specimens from all groups were also collected for the assessment of hepatic and nephrotic level of inflammatory mediators (TNF-α, IL-6β, nuclear factor kappa B (NF-κB), Caspase-3, oxidative parameters (MDA, SOD, TAC, NO) and DNA fragmentation. Histopathological changes in liver and kidney were also evaluated. Results: Three weeks of AlCl3 (70 mg/kg, IP) exposure induced nephro- and hepato-toxicity in rats. Treatment by the all used drugs showed protection against hazards of AlCl3. The protective effects were indicated by the significant decrease in ALT, AST, ALP, LDH as well as total bilirubin, lipids, cholesterol, triglycerides, glucose, creatinine and urea levels which were increased by Al. Liver and kidney of the treated groups showed decrease in MDA, NO, TNF-α, IL-6β, NF-κB, caspase-3 and DNA fragmentation which were increased by Al, together with significant increase in total proteins, SOD and TAC which were decreased by Al. The protection against both nephro- and hepato-toxicity was more pronounced especially with CoQ10 and wheat grass than the other used drugs. Histopathological examinations confirmed the biochemical results of toxicity and of protection. Conclusion: Protection from nephrotoxicity, hepatotoxicity and the consequent degenerations induced by Al can be achieved by using different drugs as CoQ10, wheatgrass, cocoa, vinpocetine and zinc, but CoQ10 as well as wheat grass possesses the most superior protection.

Keywords: aluminum, nephrotoxicity, hepatotoxicity, coenzyme Q10, wheatgrass, cocoa, vinpocetine, zinc

Procedia PDF Downloads 334
679 Miniaturizing the Volumetric Titration of Free Nitric Acid in U(vi) Solutions: On the Lookout for a More Sustainable Process Radioanalytical Chemistry through Titration-On-A-Chip

Authors: Jose Neri, Fabrice Canto, Alastair Magnaldo, Laurent Guillerme, Vincent Dugas

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A miniaturized and automated approach for the volumetric titration of free nitric acid in U(VI) solutions is presented. Free acidity measurement refers to the acidity quantification in solutions containing hydrolysable heavy metal ions such as U(VI), U(IV) or Pu(IV) without taking into account the acidity contribution from the hydrolysis of such metal ions. It is, in fact, an operation having an essential role for the control of the nuclear fuel recycling process. The main objective behind the technical optimization of the actual ‘beaker’ method was to reduce the amount of radioactive substance to be handled by the laboratory personnel, to ease the instrumentation adjustability within a glove-box environment and to allow a high-throughput analysis for conducting more cost-effective operations. The measurement technique is based on the concept of the Taylor-Aris dispersion in order to create inside of a 200 μm x 5cm circular cylindrical micro-channel a linear concentration gradient in less than a second. The proposed analytical methodology relies on the actinide complexation using pH 5.6 sodium oxalate solution and subsequent alkalimetric titration of nitric acid with sodium hydroxide. The titration process is followed with a CCD camera for fluorescence detection; the neutralization boundary can be visualized in a detection range of 500nm- 600nm thanks to the addition of a pH sensitive fluorophore. The operating principle of the developed device allows the active generation of linear concentration gradients using a single cylindrical micro channel. This feature simplifies the fabrication and ease of use of the micro device, as it does not need a complex micro channel network or passive mixers to generate the chemical gradient. Moreover, since the linear gradient is determined by the liquid reagents input pressure, its generation can be fully achieved in faster intervals than one second, being a more timely-efficient gradient generation process compared to other source-sink passive diffusion devices. The resulting linear gradient generator device was therefore adapted to perform for the first time, a volumetric titration on a chip where the amount of reagents used is fixed to the total volume of the micro channel, avoiding an important waste generation like in other flow-based titration techniques. The associated analytical method is automated and its linearity has been proven for the free acidity determination of U(VI) samples containing up to 0.5M of actinide ion and nitric acid in a concentration range of 0.5M to 3M. In addition to automation, the developed analytical methodology and technique greatly improves the standard off-line oxalate complexation and alkalimetric titration method by reducing a thousand fold the required sample volume, forty times the nuclear waste per analysis as well as the analysis time by eight-fold. The developed device represents, therefore, a great step towards an easy-to-handle nuclear-related application, which in the short term could be used to improve laboratory safety as much as to reduce the environmental impact of the radioanalytical chain.

Keywords: free acidity, lab-on-a-chip, linear concentration gradient, Taylor-Aris dispersion, volumetric titration

Procedia PDF Downloads 384
678 Online Course of Study and Job Crafting for University Students: Development Work and Feedback

Authors: Hannele Kuusisto, Paivi Makila, Ursula Hyrkkanen

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Introduction: There have been arguments about the skills university students should have when graduated. Current trends argue that as well as the specific job-related skills the graduated students need problem-solving, interaction and networking skills as well as self-management skills. Skills required in working life are also considered in the Finnish national project called VALTE (short for 'prepared for working life'). The project involves 11 Finnish school organizations. As one result of this project, a five-credit independent online course in study and job engagement as well as in study and job crafting was developed at Turku University of Applied Sciences. The aim of the oral or e-poster presentation is to present the online course developed in the project. The purpose of this abstract is to present the development work of the online course and the feedback received from the pilots. Method: As the University of Turku is the leading partner of the VALTE project, the collaborative education platform ViLLE (https://ville.utu.fi, developed by the University of Turku) was chosen as the online platform for the course. Various exercise types with automatic assessment were used; for example, quizzes, multiple-choice questions, classification exercises, gap filling exercises, model answer questions, self-assessment tasks, case tasks, and collaboration in Padlet. In addition, the free material and free platforms on the Internet were used (Youtube, Padlet, Todaysmeet, and Prezi) as well as the net-based questionnaires about the study engagement and study crafting (made with Webropol). Three teachers with long teaching experience (also with job crafting and online pedagogy) and three students working as trainees in the project developed the content of the course. The online course was piloted twice in 2017 as an elective course for the students at Turku University of Applied Sciences, a higher education institution of about 10 000 students. After both pilots, feedback from the students was gathered and the online course was developed. Results: As the result, the functional five-credit independent online course suitable for students of different educational institutions was developed. The student feedback shows that students themselves think that the developed online course really enhanced their job and study crafting skills. After the course, 91% of the students considered their knowledge in job and study engagement as well as in job and study crafting to be at a good or excellent level. About two-thirds of the students were going to exploit their knowledge significantly in the future. Students appreciated the variability and the game-like feeling of the exercises as well as the opportunity to study online at the time and place they chose themselves. On a five-point scale (1 being poor and 5 being excellent), the students graded the clarity of the ViLLE platform as 4.2, the functionality of the platform as 4.0 and the easiness of operating as 3.9.

Keywords: job crafting, job engagement, online course, study crafting, study engagement

Procedia PDF Downloads 149
677 Surgical School Project: Implementation Educational Plan for Adolescents Awaiting Bariatric Surgery

Authors: Brooke Sweeney, David White, Felix Amparano, Nick A. Clark, Amy R. Beck, Mathew Lindquist, Lora Edwards, Julie Vandal, Jennifer Lisondra, Katie Cox, Renee Arensberg, Allen Cummins, Jazmine Cedeno, Jason D. Fraser, Kelsey Dean, Helena H. Laroche, Cristina Fernandez

Abstract:

Background: National organizations call for standardized pre-surgical requirements and education to optimize postoperative outcomes. Since 2017 our surgery program has used defined protocols and educational curricula pre- and post-surgery. In response to patient outcomes, our educational content was refined to include quizzes to assess patient knowledge and surgical preparedness. We aim to optimize adolescent pre-bariatric surgery preparedness by improving overall aggregate pre-surgical assessment performance from 68% to 80% within 12 months. Methods: A multidisciplinary improvement team was developed within the weight management clinic (WMC) of our tertiary care, free-standing children’s hospital. A manual has been utilized since 2017, with limitations in consistent delivery and patient uptake of information. The curriculum has been improved to include quizzes administered during WMC visits prior to bariatric surgery. The initial outcome measure is the pre-surgical quiz score of adolescents preparing for bariatric surgery. Process measure was the number of questions answered correctly to test the questions. Baseline performance was determined by a patient assessment survey of pre-surgical preparedness at patient visits. Plan-Do-Study-Act cycles (PDSA) included: 1) creation and implementation of a refined curriculum, 2) development of 5 new quizzes based upon learning objectives, and 3) improving provider-lead teaching and quiz administration within clinic workflow. Run charts assessed impact over time. Results: A total of 346 quiz questions were administered to 34 adolescents. The outcome measure improved from a baseline mean of 68% to 86% following PDSA 2 cycles, and it was sustained. Conclusion/Implication: Patient/family comprehension of surgical preparedness improved with standardized education via team member-led teaching and assessment using quizzes during pre-surgical clinic visits. The next steps include launching redesigned teaching materials with modules correlated to quizzes and assessment of comprehension and outcomes post-surgically.

Keywords: bariatric surgery, adolescent, clinic, pre-bariatric training

Procedia PDF Downloads 59
676 The Stem Cell Transcription Co-factor Znf521 Sustains Mll-af9 Fusion Protein In Acute Myeloid Leukemias By Altering The Gene Expression Landscape

Authors: Emanuela Chiarella, Annamaria Aloisio, Nisticò Clelia, Maria Mesuraca

Abstract:

ZNF521 is a stem cell-associated transcription co-factor, that plays a crucial role in the homeostatic regulation of the stem cell compartment in the hematopoietic, osteo-adipogenic, and neural system. In normal hematopoiesis, primary human CD34+ hematopoietic stem cells display typically a high expression of ZNF521, while its mRNA levels rapidly decrease when these progenitors progress towards erythroid, granulocytic, or B-lymphoid differentiation. However, most acute myeloid leukemias (AMLs) and leukemia-initiating cells keep high ZNF521 expression. In particular, AMLs are often characterized by chromosomal translocations involving the Mixed Lineage Leukemia (MLL) gene, which MLL gene includes a variety of fusion oncogenes arisen from genes normally required during hematopoietic development; once they are fused, they promote epigenetic and transcription factor dysregulation. The chromosomal translocation t(9;11)(p21-22;q23), fusing the MLL gene with AF9 gene, results in a monocytic immune phenotype with an aggressive course, frequent relapses, and a short survival time. To better understand the dysfunctional transcriptional networks related to genetic aberrations, AML gene expression profile datasets were queried for ZNF521 expression and its correlations with specific gene rearrangements and mutations. The results showed that ZNF521 mRNA levels are associated with specific genetic aberrations: the highest expression levels were observed in AMLs involving t(11q23) MLL rearrangements in two distinct datasets (MILE and den Boer); elevated ZNF521 mRNA expression levels were also revealed in AMLs with t(7;12) or with internal rearrangements of chromosome 16. On the contrary, relatively low ZNF521 expression levels seemed to be associated with the t(8;21) translocation, that in turn is correlated with the AML1-ETO fusion gene or the t(15;17) translocation and in AMLs with FLT3-ITD, NPM1, or CEBPα double mutations. Invitro, we found that the enforced co-expression of ZNF521 in cord blood-derived CD34+ cells induced a significant proliferative advantage, improving MLL-AF9 effects on the induction of proliferation and the expansion of leukemic progenitor cells. Transcriptome profiling of CD34+ cells transduced with either MLL-AF9, ZNF521, or a combination of the two transgenes highlighted specific sets of up- or down-regulated genes that are involved in the leukemic phenotype, including those encoding transcription factors, epigenetic modulators, and cell cycle regulators as well as those engaged in the transport or uptake of nutrients. These data enhance the functional cooperation between ZNF521 and MA9, resulting in the development, maintenance, and clonal expansion of leukemic cells. Finally, silencing of ZNF521 in MLL-AF9-transformed primary CD34+ cells inhibited their proliferation and led to their extinction, as well as ZNF521 silencing in the MLL-AF9+ THP-1 cell line resulted in an impairment of their growth and clonogenicity. Taken together, our data highlight ZNF521 role in the control of self-renewal and in the immature compartment of malignant hematopoiesis, which, by altering the gene expression landscape, contributes to the development and/or maintenance of AML acting in concert with the MLL-AF9 fusion oncogene.

Keywords: AML, human zinc finger protein 521 (hZNF521), mixed lineage leukemia gene (MLL) AF9 (MLLT3 or LTG9), cord blood-derived hematopoietic stem cells (CB-CD34+)

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675 Empowering Youth Through Pesh Poultry: A Transformative Approach to Addressing Unemployment and Fostering Sustainable Livelihoods in Busia District, Uganda

Authors: Bisemiire Anthony,

Abstract:

PESH Poultry is a business project proposed specifically to solve unemployment and income-related problems affecting the youths in the Busia district. The project is intended to transform the life of the youth in terms of economic, social and behavioral, as well as the domestic well-being of the community at large. PESH Poultry is a start-up poultry farm that will be engaged in the keeping of poultry birds, broilers and layers for the production of quality and affordable poultry meat and eggs respectively and other poultry derivatives targeting consumers in eastern Uganda, for example, hotels, restaurants, households and bakeries. We intend to use a semi-intensive system of farming, where water and some food are provided in a separate nighttime shelter for the birds; our location will be in Lumino, Busia district. The poultry project will be established and owned by Bisemiire Anthony, Nandera Patience, Naula Justine, Bwire Benjamin and other investors. The farm will be managed and directed by Nandera Patience, who has five years of work experience and business administration knowledge. We will sell poultry products, including poultry eggs, chicken meat, feathers and poultry manure. We also offer consultancy services for poultry farming. Our eggs and chicken meat are hygienic, rich in protein and high quality. We produce processes and packages to meet the standard organization of Uganda and international standards. The business project shall comprise five (5) workers on the key management team who will share various roles and responsibilities in the identified business functions such as marketing, finance and other related poultry farming activities. PESH Poultry seeks 30 million Ugandan shillings in long-term financing to cover start-up costs, equipment, building expenses and working capital. Funding for the launch of the business will be provided primarily by equity from the investors. The business will reach positive cash flow in its first year of operation, allowing for the expected repayment of its loan obligations. Revenue will top UGX 11,750,000, and net income will reach about UGX115 950,000 in the 1st year of operation. The payback period for our project is 2 years and 3 months. The farm plans on starting with 1000 layer birds and 1000 broiler birds, 20 workers in the first year of operation.

Keywords: chicken, pullets, turkey, ducks

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674 Serum Sickness-Like Reaction to D-Mannose Supplement

Authors: Emma Plante, Charles Ekwunwa, Diego Illanes

Abstract:

Introduction: Serum Sickness-Like Reaction (SSLR) is an inflammatory immune response characterized by a rash, polyarthralgias, and fever. SSLR usually occurs in response to a new medication (most commonly antibiotics, anticonvulsants, or antiinflammatory agents) and is believed to involve the formation of drug-specific immune complexes. Here we present a case of a 16-year-old female patient who developed an SSLR in response to the D-mannose-containing over-the-counter supplement, Uqora, used to promote bladder health. Methodology: The methodology for this study included a thorough literature search for other cases of SSLR associated with D-Mannose containing products. Data collection was performed through a review of the patient’s medical record, including history, physical examination, relevant laboratory results, and treatment plan. Findings: A 16-year-old female with a history of overactive bladder and anemia presented with a diffuse urticarial rash, headaches, joint pain, and swelling for three days. Her medications included oral contraceptive pills, iron, mirabegron, UQora, and a probiotic. Physical examination revealed a diffuse urticarial rash, and her musculoskeletal exam revealed swelling and tenderness in her wrists. Her CBC, basic metabolic panel, liver function panel, lyme titers, and urinalysis were all within normal limits. The patient was referred to an allergist, who diagnosed her with SSLR. All medications were discontinued, and she was treated with a 7-day course of prednisone and cetirizine. Her symptoms resolved, and her medications were slowly resumed sequentially over several months. However, UQora triggered a recurrence of her symptoms, and it was identified as the culprit medication. Consequently, UQora was permanently discontinued, and the patient has remained symptom-free. Conclusion: This case report describes the first documented case of SSLR caused by UQora (active ingredient D-mannose). D-Mannose is a monosaccharide found in many plants and fruits, and it is commonly used to prevent urinary tract infections. While the clinical features and timeline, in this case, were typical of SSLR, UQora as the trigger was highly unusual. Clinicians should be aware of the diverse triggers of SSLR and the importance of prompt identification and management to enhance patient safety. It is possible D-mannose was not the trigger, and further research is necessary to better understand the potential therapeutic applications of D-mannose, as well as the potential risks and interactions.

Keywords: serum sickness-like reaction, d-mannose, hypersensitivity reaction, urticaria

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673 Congenital Diaphragmatic Hernia Outcomes in a Low-Volume Center

Authors: Michael Vieth, Aric Schadler, Hubert Ballard, J. A. Bauer, Pratibha Thakkar

Abstract:

Introduction: Congenital diaphragmatic hernia (CDH) is a condition characterized by the herniation of abdominal contents into the thoracic cavity requiring postnatal surgical repair. Previous literature suggests improved CDH outcomes at high-volume regional referral centers compared to low-volume centers. The purpose of this study was to examine CDH outcomes at Kentucky Children’s Hospital (KCH), a low-volume center, compared to the Congenital Diaphragmatic Hernia Study Group (CDHSG). Methods: A retrospective chart review was performed at KCH from 2007-2019 for neonates with CDH, and then subdivided into two cohorts: those requiring ECMO therapy and those not requiring ECMO therapy. Basic demographic data and measures of mortality and morbidity including ventilator days and length of stay were compared to the CDHSG. Measures of morbidity for the ECMO cohort including duration of ECMO, clinical bleeding, intracranial hemorrhage, sepsis, need for continuous renal replacement therapy (CRRT), need for sildenafil at discharge, timing of surgical repair, and total ventilator days were collected. Statistical analysis was performed using IBM SPSS Statistics version 28. One-sample t-tests and one-sample Wilcoxon Signed Rank test were utilized as appropriate.Results: There were a total of 27 neonatal patients with CDH at KCH from 2007-2019; 9 of the 27 required ECMO therapy. The birth weight and gestational age were similar between KCH and the CDHSG (2.99 kg vs 2.92 kg, p =0.655; 37.0 weeks vs 37.4 weeks, p =0.51). About half of the patients were inborn in both cohorts (52% vs 56%, p =0.676). KCH cohort had significantly more Caucasian patients (96% vs 55%, p=<0.001). Unadjusted mortality was similar in both groups (KCH 70% vs CDHSG 72%, p =0.857). Using ECMO utilization (KCH 78% vs CDHSG 52%, p =0.118) and need for surgical repair (KCH 95% vs CDHSG 85%, p =0.060) as proxy for severity, both groups’ mortality were comparable. No significant difference was noted for pulmonary outcomes such as average ventilator days (KCH 43.2 vs. CDHSG 17.3, p =0.078) and home oxygen dependency (KCH 44% vs. CDHSG 24%, p =0.108). Average length of hospital stay for patients treated at KCH was similar to CDHSG (64.4 vs 49.2, p=1.000). Conclusion: Our study demonstrates that outcome in CDH patients is independent of center’s case volume status. Management of CDH with a standardized approach in a low-volume center can yield similar outcomes. This data supports the treatment of patients with CDH at low-volume centers as opposed to transferring to higher-volume centers.

Keywords: ECMO, case volume, congenital diaphragmatic hernia, congenital diaphragmatic hernia study group, neonate

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672 Angiopermissive Foamed and Fibrillar Scaffolds for Vascular Graft Applications

Authors: Deon Bezuidenhout

Abstract:

Pre-seeding with autologous endothelial cells improves the long-term patency of synthetic vascular grafts levels obtained with autografts, but is limited to a single centre due to resource, time and other constraints. Spontaneous in vivo endothelialization would obviate the need for pre-seeding, but has been shown to be absent in man due to limited transanastomotic and fallout healing, and the lack of transmural ingrowth due to insufficient porosity. Two types of graft scaffolds with increased interconnected porosity for improved tissue ingrowth and healing are thus proposed and described. Foam-type polyurethane (PU) scaffolds with small, medium and large, interconnected pores were made by phase inversion and spherical porogen extraction, with and without additional surface modification with covalently attached heparin and subsequent loading with and delivery of growth factors. Fibrillar scaffolds were made either by standard electrospinning using degradable PU (Degrapol®), or by dual electrospinning using non-degradable PU. The latter process involves sacrificial fibres that are co-spun with structural fibres and subsequently removed to increased porosity and pore size. Degrapol samples were subjected to in vitro degradation, and all scaffold types were evaluated in vivo for tissue ingrowth and vascularization using rat subcutaneous model. The foam scaffolds were additionally evaluated in a circulatory (rat infrarenal aortic interposition) model that allows for the grafts to be anastomotically and/or ablumenally isolated to discern and determine endothelialization mode. Foam-type grafts with large (150 µm) pores showed improved subcutaneous healing in terms of vascularization and inflammatory response over smaller pore sizes (60 and 90µm), and vascularization of the large porosity scaffolds was significantly increased by more than 70% by heparin modification alone, and by 150% to 400% when combined with growth factors. In the circulatory model, extensive transmural endothelialization (95±10% at 12 w) was achieved. Fallout healing was shown to be sporadic and limited in groups that were ablumenally isolated to prevent transmural ingrowth (16±30% wrapped vs. 80±20% control; p<0.002). Heparinization and GF delivery improved both mural vascularization and lumenal endothelialization. Degrapol electrospun scaffolds showed decrease in molecular mass and corresponding tensile strength over the first 2 weeks, but very little decrease in mass over the 4w test period. Studies on the effect of tissue ingrowth with and without concomitant degradation of the scaffolds, are being used to develop material models for the finite element modelling. In the case of the dual-spun scaffolds, the PU fibre fraction could be controlled shown to vary linearly with porosity (P = −0.18FF +93.5, r2=0.91), which in turn showed inverse linear correlation with tensile strength and elastic modulus (r2 > 0.96). Calculated compliance and burst pressures of the scaffolds increased with fibre fraction, and compliances matching the human popliteal artery (5-10 %/100 mmHg), and high burst pressures (> 2000 mmHg) could be achieved. Increasing porosity (76 to 82 and 90%) resulted in increased tissue ingrowth from 33±7 to 77±20 and 98±1% after 28d. Transmural endothelialization of highly porous foamed grafts is achievable in a circulatory model, and the enhancement of porosity and tissue ingrowth may hold the key the development of spontaneously endothelializing electrospun grafts.

Keywords: electrospinning, endothelialization, porosity, scaffold, vascular graft

Procedia PDF Downloads 292