Search results for: localization and transmission

Authors: M. S. Stepanova, V. V. Zakharov, P. D. Khavlyuk, I. D. Skurlov, A. Y. Dubovik, A. L. Rogach

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Carbon dots are small carbon-based spherical nanoparticles, which are typically less than 10 nm in size that can be modified with surface passivation and heteroatoms doping. The light-absorbing ability of carbon dots has attracted a significant amount of attention in photoluminescence for bioimaging and fluorescence sensing applications owing to their advantages, such as tunable fluorescence emission, photo- and thermostability and low toxicity. In this study, carbon dots were synthesized by the solvothermal method from citric acid and ethylenediamine dissolved in water. The solution was heated for 5 hours at 200°C and then cooled down to room temperature. The carbon dots films were obtained by evaporation from a high-concentration aqueous solution. The increase of both luminescence intensity and light transmission was obtained as a result of a 405 nm laser exposure to a part of the carbon dots film, which was detected using a confocal laser scanning microscope (LSM 710, Zeiss). Blueshift up to 35 nm of the luminescence spectrum is observed as luminescence intensity, which is increased more than twofold. The exact value of the shift depends on the time of the laser exposure. This shift can be caused by the modification of surface groups at the carbon dots, which are responsible for long-wavelength luminescence. In addition, a shift of the absorption peak by 10 nm and a decrease in the optical density at the wavelength of 350 nm is detected, which is responsible for the absorption of surface groups. The obtained sample was also studied with time-resolved confocal fluorescence microscope (MicroTime 100, PicoQuant), which made it possible to receive a time-resolved photoluminescence image and construct emission decays of the laser-exposed and non-exposed areas. 5 MHz pulse rate impulse laser has been used as a photoluminescence excitation source. Photoluminescence decay was approximated by two exhibitors. The laser-exposed area has the amplitude of the first-lifetime component (A1) twice as much as before, with increasing τ1. At the same time, the second-lifetime component (A2) decreases. These changes evidence a modification of the surface groups of carbon dots. The detected effect can be used to create thermostable fluorescent marks, the physical size of which is bounded by the diffraction limit of the optics (~ 200-300 nm) used for exposure and to improve the optical properties of carbon dots or in the field of optical encryption. Acknowledgements: This work was supported by the Ministry of Science and Higher Education of Russian Federation, goszadanie no. 2019-1080 and financially supported by Government of Russian Federation, Grant 08-08.

Keywords: carbon dots, photoactivation, optical properties, photoluminescence and absorption spectra

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Authors: Kanti Sapkota, Do Hyun Lee, Sung Soo Han

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Nanocomposites have been widely used in various fields such as electronics, catalysis, and in chemical, biological, biomedical and optical fields. They display broad biomedical properties like antidiabetic, anticancer, antioxidant, antimicrobial and antibacterial activities. Moreover, nanomaterials have been used for wastewater treatment. Particularly, bimetallic hybrid nanocomposites exhibit unique features as compared to their monometallic components. Hybrid nanomaterials not only afford the multifunctionality endowed by their constituents but can also show synergistic properties. In addition, these hybrid nanomaterials have noteworthy catalytic and optical properties. Notably, Au−Ag based nanoparticles can be employed in sensor and catalysis due to their characteristic composition-tunable plasmonic properties. Due to their importance and usefulness, various efforts were developed for their preparation. Generally, chemical methods have been described to synthesize such bimetallic nanocomposites. In such chemical synthesis, harmful and hazardous chemicals cause environmental contamination and increase toxicity levels. Therefore, ecologically benevolent processes for the synthesis of nanomaterials are highly desirable to diminish such environmental and safety concerns. In this regard, here we disclose a simple, cost-effective, external additive free and eco-friendly method for the synthesis of Au-Ag@AgCl nanocomposites using Nephrolepis cordifolia root extract. Au-Ag@AgCl NCs were obtained by the simultaneous reduction of cationic Ag and Au into AgCl in the presence of plant extract. The particle size of 10 to 50 nm was observed with the average diameter of 30 nm. The synthesized nanocomposite was characterized by various modern characterization techniques. For example, UV−visible spectroscopy was used to determine the optical activity of the synthesized NCs, and Fourier transform infrared (FT-IR) spectroscopy was employed to investigate the functional groups present in the biomolecules that were responsible for both reducing and capping agents during the formation of nanocomposites. Similarly, powder X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA) and energy-dispersive X-ray (EDX) spectroscopy were used to determine crystallinity, size, oxidation states, thermal stability and weight loss of the synthesized nanocomposites. As a synthetic application, the synthesized nanocomposite exhibited excellent catalytic activity for the multicomponent synthesis of biologically interesting quinoline molecules via domino annulation-aromatization reaction of aniline, arylaldehyde, and phenyl acetylene derivatives. Interestingly, the nanocatalyst was efficiently recycled for five times without substantial loss of catalytic properties.

Keywords: nanoparticles, catalysis, multicomponent, quinoline

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Authors: Elena Maria Scalisi, Roberta Pecoraro, Martina Contino, Sara Ignoto, Carmelo Iaria, Santi Concetto Pavone, Gino Sorbello, Loreto Di Donato, Maria Violetta Brundo

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5G Technology is evolving to satisfy a variety of service requirements that may allow high data-rate connections (1Gbps) and lower latency times than current (<1ms). In order to support a high data transmission speed and a high traffic service for eMBB (enhanced mobile broadband) use cases, 5G systems have the characteristic of using different frequency bands of the radio wave spectrum (700 MHz, 3.6-3.8 GHz and 26.5-27.5 GHz), thus taking advantage of higher frequencies than previous mobile radio generations (1G-4G). However, waves at higher frequencies have a lower capacity to propagate in free space and therefore, in order to guarantee the capillary coverage of the territory for high reliability applications, it will be necessary to install a large number of repeaters. Following the introduction of this new technology, there has been growing concern over the past few months about possible harmful effects on human health. The aim of this preliminary study is to evaluate possible short term effects induced by 5G-millimeter waves on embryonic development and early life stages of Danio rerio by Z-FET. We exposed developing zebrafish at frequency of 27 GHz, with a standard pyramidal horn antenna placed at 15 cm far from the samples holder ensuring an incident power density of 10 mW/cm2. During the exposure cycle, from 6 h post fertilization (hpf) to 96 hpf, we measured a different morphological endpoints every 24 hours. Zebrafish embryo toxicity test (Z-FET) is a short term test, carried out on fertilized eggs of zebrafish and it represents an effective alternative to acute test with adult fish (OECD, 2013). We have observed that 5G did not reveal significant impacts on mortality nor on morphology because exposed larvae showed a normal detachment of the tail, presence of heartbeat, well-organized somites, therefore hatching rate was lower than untreated larvae even at 48 h of exposure. Moreover, the immunohistochemical analysis performed on larvae showed a negativity to the HSP-70 expression used as a biomarkers. This is a preliminary study on evaluation of potential toxicity induced by 5G and it seems appropriate to underline the importance that further studies would take, aimed at clarifying the probable real risk of exposure to electromagnetic fields.

Keywords: Biomarker of exposure, embryonic development, 5G waves, zebrafish embryo toxicity test

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Authors: Raj Kumar, Prem Felix Siril

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The poor aqueous solubility of many pharmaceutical drugs and potential drug candidates is a big challenge in drug development. Nanoformulation of such candidates is one of the major solutions for the delivery of such drugs. We initially developed the evaporation assisted solvent-antisolvent interaction (EASAI) method. EASAI method is use full to prepared nanoparticles of poor water soluble drugs with spherical morphology and particles size below 100 nm. However, to further improve the effect formulation to reduce number of dose and side effect it is important to control the delivery of drugs. However, many drug delivery systems are available. Among the many nano-drug carrier systems, solid lipid nanoparticles (SLNs) have many advantages over the others such as high biocompatibility, stability, non-toxicity and ability to achieve controlled release of drugs and drug targeting. SLNs can be administered through all existing routes due to high biocompatibility of lipids. SLNs are usually composed of lipid, surfactant and drug were encapsulated in lipid matrix. A number of non-steroidal anti-inflammatory drugs (NSAIDs) have poor bioavailability resulting from their poor aqueous solubility. In the present work, SLNs loaded with NSAIDs such as Nabumetone (NBT), Ketoprofen (KP) and Ibuprofen (IBP) were successfully prepared using different lipids and surfactants. We studied and optimized experimental parameters using a number of lipids, surfactants and NSAIDs. The effect of different experimental parameters such as lipid to surfactant ratio, volume of water, temperature, drug concentration and sonication time on the particles size of SLNs during the preparation using hot-melt sonication was studied. It was found that particles size was directly proportional to drug concentration and inversely proportional to surfactant concentration, volume of water added and temperature of water. SLNs prepared at optimized condition were characterized thoroughly by using different techniques such as dynamic light scattering (DLS), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), X-ray diffraction (XRD) and differential scanning calorimetry and Fourier transform infrared spectroscopy (FTIR). We successfully prepared the SLN of below 220 nm using different lipids and surfactants combination. The drugs KP, NBT and IBP showed 74%, 69% and 53% percentage of entrapment efficiency with drug loading of 2%, 7% and 6% respectively in SLNs of Campul GMS 50K and Gelucire 50/13. In-vitro drug release profile of drug loaded SLNs is shown that nearly 100% of drug was release in 6 h.

Keywords: nanoparticles, delivery, solid lipid nanoparticles, hot-melt sonication, poor water soluble drugs, solubility, bioavailability

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Authors: Le Jiang, Chua Jinxing

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Introduction: The recent outbreak of Ebola virus disease in the west Africa has drawn global concern. With a high fatality rate and direct human-to-human transmission, it has spread between countries and caused great damages for patients and family who are affected. Being the designated hospital to manage epidemic outbreak in Singapore, Tan Tock Seng Hospital (TTSH) is facing great challenges in preparation and managing of potential outbreak of emerging infectious disease such as Ebola virus disease. Aim: We conducted an infection control drill in TTSH emergency department to assess the readiness of healthcare and allied health workers in managing suspected Ebola patients. It also helps to review current Ebola clinical protocol and work instruction to ensure more smooth and safe practice in managing Ebola patients in TTSH emergency department. Result: General preparedness level of staffs involved in managing Ebola virus disease in TTSH emergency department is not adequate. Knowledge deficits of staffs on Ebola personal protective equipment gowning and degowning process increase the risk of potential cross contamination in patient care. Loopholes are also found in current clinical protocol, such as unclear instructions and inaccurate information, which need to be revised to promote better staff performance in patient management. Logistic issues such as equipment dysfunction and inadequate supplies can lead to ineffective communication among teams and causing harm to patients in emergency situation. Conclusion: The infection control drill identified the need for more well-structured and clear clinical protocols to be in place to promote participants performance. In addition to quality protocols and guidelines, systemic training and annual refresher for all staffs in the emergency department are essential to prepare staffs for the outbreak of Ebola virus disease. Collaboration and communication with allied health staffs are also crucial for smooth delivery of patient care and minimising the potential human suffering, properties loss or injuries caused by disease. Therefore, more clinical drills with collaboration among various departments involved are recommended to be conducted in the future to monitor and assess readiness of TTSH emergency department in managing Ebola virus disease.

Keywords: ebola, emergency department, infection control drill, Tan Tock Seng Hospital

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Authors: Magdalena Maria Rost-Roszkowska, Alina Chachulska-Żymełka, Monika Tarnawska, Maria Augustyniak, Alina Kafel, Agnieszka Babczyńska

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Autophagy is a form of cell remodeling in which an internalization of organelles into vacuoles that are called autophagosomes occur. Autophagosomes are the targets of lysosomes, thus causing digestion of cytoplasmic components. Eventually, it can lead to the death of the entire cell. However, in response to several stress factors, e.g., starvation, heavy metals (e.g., cadmium) autophagy can also act as a pro-survival factor, protecting the cell against its death. The main aim of our studies was to check if the process of autophagy, which could appear in the midgut epithelium after Cd treatment, can be fixed during the following generations of insects. As a model animal, we chose the beet armyworm Spodoptera exigua Hübner (Lepidoptera: Noctuidae), a well-known polyphagous pest of many vegetable crops. We analyzed specimens at final larval stage (5th larval stage), due to its hyperfagy, resulting in great amount of cadmium assimilate. The culture consisted of two strains: a control strain (K) fed a standard diet, and a cadmium strain (Cd), fed on standard diet supplemented with cadmium (44 mg Cd per kg of dry weight of food) for 146 generations, both strains. In addition, the control insects were transferred to the Cd supplemented diet (5 mg Cd per kg of dry weight of food, 10 mg Cd per kg of dry weight of food, 20 mg Cd per kg of dry weight of food, 44 mg Cd per kg of dry weight of food). Therefore, we obtained Cd1, Cd2, Cd3 and KCd experimental groups. Autophagy has been examined using transmission electron microscope. During this process, degenerated organelles were surrounded by a membranous phagophore and enclosed in an autophagosome. Eventually, after the autophagosome fused with a lysosome, an autolysosome was formed and the process of the digestion of organelles began. During the 1st year of the experiment, we analyzed specimens of 6 generations in all the lines. The intensity of autophagy depends significantly on the generation, tissue and cadmium concentration in the insect rearing medium. In the Ist, IInd, IIIrd, IVth, Vth and VIth generation the intensity of autophagy in the midguts from cadmium-exposed strains decreased gradually according to the following order of strains: Cd1, Cd2, Cd3 and KCd. The higher amount of cells with autophagy was observed in Cd1 and Cd2. However, it was still higher than the percentage of cells with autophagy in the same tissues of the insects from the control and multigenerational cadmium strain. This may indicate that during 6-generational exposure to various Cd concentration, a preserved tolerance to cadmium was not maintained. The study has been financed by the National Science Centre Poland, grant no 2016/21/B/NZ8/00831.

Keywords: autophagy, cell death, digestive system, ultrastructure

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Authors: Osman Adiguzel

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Shape memory effect is a peculiar property exhibited by certain alloy systems and based on martensitic transformation, and shape memory properties are closely related to the microstructures of the material. Shape memory effect is linked with martensitic transformation, which is a solid state phase transformation and occurs with the cooperative movement of atoms by means of lattice invariant shears on cooling from high-temperature parent phase. Lattice twinning and detwinning can be considered as elementary processes activated during the transformation. Thermally induced martensite occurs as martensite variants, in self-accommodating manner and consists of lattice twins. Also, this martensite is called the twinned martensite or multivariant martensite. Deformation of shape memory alloys in martensitic state proceeds through a martensite variant reorientation. The martensite variants turn into the reoriented single variants with deformation, and the reorientation process has great importance for the shape memory behavior. Copper based alloys exhibit this property in metastable β- phase region, which has DO3 –type ordered lattice in ternary case at high temperature, and these structures martensiticaly turn into the layered complex structures with lattice twinning mechanism, on cooling from high temperature parent phase region. The twinning occurs as martensite variants with lattice invariant shears in two opposite directions, <110 > -type directions on the {110}- type plane of austenite matrix. Lattice invariant shear is not uniform in copper based ternary alloys and gives rise to the formation of unusual layered structures, like 3R, 9R, or 18R depending on the stacking sequences on the close-packed planes of the ordered lattice. The unit cell and periodicity are completed through 18 atomic layers in case of 18R-structure. On the other hand, the deformed material recovers the original shape on heating above the austenite finish temperature. Meanwhile, the material returns to the twinned martensite structures (thermally induced martensite structure) in one way (irreversible) shape memory effect on cooling below the martensite finish temperature, whereas the material returns to the detwinned martensite structure (deformed martensite) in two-way (reversible) shape memory effect. Shortly one can say that the microstructural mechanisms, responsible for the shape memory effect are the twinning and detwinning processes as well as martensitic transformation. In the present contribution, x-ray diffraction, transmission electron microscopy (TEM) and differential scanning calorimetry (DSC) studies were carried out on two copper-based ternary alloys, CuZnAl, and CuAlMn.

Keywords: shape memory effect, martensitic transformation, twinning and detwinning, layered structures

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Authors: Zachary Cooper-Baldock, Paulo E. Santos, Russell S. A. Brinkworth, Karl Sammut

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- In recent years, large unmanned underwater vehicles such as the Boeing Voyager and Anduril Ghost Shark have been developed. These vessels can be structured to contain onboard internal payload bays. These payload bays can serve a variety of purposes – including the launch and recovery (LAR) of smaller underwater vehicles. The LAR of smaller vessels is extremely important, as it enables transportation over greater distances, increased time on station, data transmission and operational safety. The larger vessel and its payload bay structure complicate the LAR of UUVs in contrast to static docks that are affixed to the seafloor, as they actively impact the local flow field. These flow field impacts require analysis to determine if UUV vessels can be safely launched and recovered inside the motherships. This research seeks to determine the hydrodynamic forces exerted on a vertically over-actuated, small, unmanned underwater vehicle (OUUV) during an internal LAR manoeuvre and compare this to an under-actuated vessel (UUUV). In this manoeuvre, the OUUV is navigated through the stern wake region of the larger vessel to a set point within the internal payload bay. The manoeuvre is simulated using ANSYS Fluent computational fluid dynamics models, covering the entire recovery of the OUUV and UUUV. The analysis of the OUUV is compared against the UUUV to determine the differences in the exerted forces. Of particular interest are the drag, pressure, turbulence and flow field effects exerted as the OUUV is driven inside the payload bay of the larger vessel. The hydrodynamic forces and flow field disturbances are used to determine the feasibility of making such an approach. From the simulations, it was determined that there was no significant detrimental physical forces, particularly with regard to turbulence. The flow field effects exerted by the OUUV are significant. The vertical thrusters exert significant wake structures, but their orientation ensures the wake effects are exerted below the UUV, minimising the impact. It was also seen that OUUV experiences higher drag forces compared to the UUUV, which will correlate to an increased energy expenditure. This investigation found no key indicators that recovery via a mothership payload bay was not feasible. The turbulence, drag and pressure phenomenon were of a similar magnitude to existing static and towed dock structures.

Keywords: underwater vehicles, submarine, autonomous underwater vehicles, auv, computational fluid dynamics, flow fields, pressure, turbulence, drag

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Authors: Sophie Baudel, Aline Duplaa, Jean Muller, Stephan Lauriol, Yann Bernard

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Argos is the main satellite telemetry system used by the wildlife research community, since its creation in 1978, for animal tracking and scientific data collection all around the world, to analyze and understand animal migrations and behavior. The marine mammals' biology is one of the major disciplines which had benefited from Argos telemetry, and conversely, marine mammals biologists’ community has contributed a lot to the growth and development of Argos use cases. The Argos constellation with 6 satellites in orbit in 2017 (Argos 2 payload on NOAA 15, NOAA 18, Argos 3 payload on NOAA 19, SARAL, METOP A and METOP B) is being extended in the following years with Argos 3 payload on METOP C (launch in October 2018), and Argos 4 payloads on Oceansat 3 (launch in 2019), CDARS in December 2021 (to be confirmed), METOP SG B1 in December 2022, and METOP-SG-B2 in 2029. Argos 4 will allow more frequency bands (600 kHz for Argos4NG, instead of 110 kHz for Argos 3), new modulation dedicated to animal (sea turtle) tracking allowing very low transmission power transmitters (50 to 100mW), with very low data rates (124 bps), enhancement of high data rates (1200-4800 bps), and downlink performance, at the whole contribution to enhance the system capacity (50,000 active beacons per month instead of 20,000 today). In parallel of this ‘institutional Argos’ constellation, in the context of a miniaturization trend in the spatial industry in order to reduce the costs and multiply the satellites to serve more and more societal needs, the French Space Agency CNES, which designs the Argos payloads, is innovating and launching the Argos ANGELS project (Argos NEO Generic Economic Light Satellites). ANGELS will lead to a nanosatellite prototype with an Argos NEO instrument (30 cm x 30 cm x 20cm) that will be launched in 2019. In the meantime, the design of the renewal of the Argos constellation, called Argos For Next Generations (Argos4NG), is on track and will be operational in 2022. Based on Argos 4 and benefitting of the feedback from ANGELS project, this constellation will allow revisiting time of fewer than 20 minutes in average between two satellite passes, and will also bring more frequency bands to improve the overall capacity of the system. The presentation will then be an overview of the Argos system, present and future and new capacities coming with it. On top of that, use cases of two Argos hardware modules will be presented: the goniometer pathfinder allowing recovering Argos beacons at sea or on the ground in a 100 km radius horizon-free circle around the beacon location and the new Argos 4 chipset called ‘Artic’, already available and tested by several manufacturers.

Keywords: Argos satellite telemetry, marine protected areas, oceanography, maritime services

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Authors: Marcelo T. Okano, Oduvaldo Vendrametto, Osmildo S. Santos, Marcelo E. Fernandes, Heide Landi

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Teaching of entrepreneurship and innovation in Brazilian universities has increased in recent years due to several factors such as the emergence of disciplines like biotechnology increased globalization reduced basic funding and new perspectives on the role of the university in the system of knowledge production Innovation is increasingly seen as an evolutionary process that involves different institutional spheres or sectors in society Entrepreneurship is a milestone on the road towards economic progress, and makes a huge contribution towards the quality and future hopes of a sector, economy or even a country. Entrepreneurship is as important in small and medium-sized enterprises (SMEs) and local markets as in large companies, and national and international markets, and is just as key a consideration for public companies as or private organizations. Entrepreneurship helps to encourage the competition in the current environment that leads to the effects of globalization. There is an increasing tendency for government policy to promote entrepreneurship for its apparent economic benefit. Accordingly, governments seek to employ entrepreneurship education as a means to stimulate increased levels of economic activity. Entrepreneurship education and training (EET) is growing rapidly in universities and colleges throughout the world, and governments are supporting it both directly and through funding major investments in advice-provision to would-be entrepreneurs and existing small businesses. The Triple Helix of university–industry–government relations is compared with alternative models for explaining the current research system in its social contexts. Communications and negotiations between institutional partners generate an overlay that increasingly reorganizes the underlying arrangements. To achieve the objective of this research was a survey of the literature on the entrepreneurship and innovation and then a field research with 100 students of Fatec. To collect the data needed for analysis, we used the exploratory research of a qualitative nature. We asked to respondents what degree of knowledge over ten related to entrepreneurship and innovation topics, responses were answered in a Likert scale with 4 levels, none, small, medium and large. We can conclude that the terms such as entrepreneurship and innovation are known by most students because the university propagates them across disciplines, lectures, and institutes innovation. The more specific items such as canvas and Design thinking model are unknown by most respondents. The importance of the University in teaching innovation and entrepreneurship in the transmission of this knowledge to the students in order to equalize the knowledge. As a future project, these items will be re-evaluated to create indicators for measuring the knowledge level.

Keywords: Brazilian universities, entrepreneurship, innovation, entrepreneurship, globalization

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Authors: Diana Cunha, Catarina Coelho, Ana Paula Relvas, Elisabeth Kastenholz

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Context: Tourist experiences have a recognized impact on the well-being of individuals. However, studies on the specific benefits of tourist experiences for families are scattered across different disciplines. This study aims to systematically review the literature to synthesize the evidence on the benefits of tourist experiences for families. Research Aim: The main objective is to systematize the evidence in the literature regarding the benefits of tourist experiences for families. Methodology: A systematic literature review was conducted using Nvivo, analyzing 33 scientific studies obtained from various databases. The search terms used were "family"/ "couple" and "tourist experience". The studies included quantitative, qualitative, mixed methods, and literature reviews. All works prior to the year 2000 were excluded, and the search was restricted to full text. A language filter was also used, considering articles in Portuguese, English, and Spanish. For NVivo analysis, information was coded based on both deductive and inductive perspectives. To minimize the subjectivity of the selection and coding process, two of the authors discussed the process and agreed on criteria that would make the coding more objective. Once the coding process in NVivo was completed, the data relating to the identification/characterization of the works were exported to the Statistical Package for the Social Sciences (SPPS), to characterize the sample. Findings: The results highlight that tourist experiences have several benefits for family systems, including the strengthening of family and marital bonds, the creation of family memories, and overall well-being and life satisfaction. These benefits contribute to both immediate relationship quality improvement and long-term family identity construction and transgenerational transmission. Theoretical Importance: This study emphasizes the systemic nature of the effects and relationships within family systems. It also shows that no harm was reported within these experiences, with only some challenges related to positive outcomes. Data Collection and Analysis Procedures: The study collected data from 33 scientific studies published predominantly after 2013. The data were analyzed using Nvivo, employing a systematic review approach. Question Addressed: The study addresses the question of the benefits of tourist experiences for families and how these experiences contribute to family functioning and individual well-being. Conclusion: Tourist experiences provide opportunities for families to enhance their interpersonal relationships and create lasting memories. The findings suggest that formal interventions based on evidence could further enhance the potential benefits of these experiences and be a valuable preventive tool in therapeutic interventions.

Keywords: family systems, individual and family well-being, marital satisfaction, tourist experiences

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Authors: Tunde Ope-Davies

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Transmediality and platformization as online content-sharing protocols have continued to accentuate the growing impact of the unprecedented digital revolution across the world. The rapid transformation across all sectors as a result of this revolution has continued to spotlight the increasing importance of new media technologies in redefining and reshaping the rhythm and dynamics of our private and public discursive practices. Equally, social and political activities are being impacted daily through the creation and transmission of political discourse content through multi-channel platforms such as mobile telephone communication, social media networks and the internet. It has been observed that digital platforms have become central to the production, processing, and distribution of multimodal social data and cultural content. The platformization paradigm thus underpins our understanding of how digital platforms enhance the production and heterogenous distribution of media and cultural content through these platforms and how this process facilitates socioeconomic and political activities. The use of multiple digital platforms to share and transmit political discourse material synchronously and asynchronously has gained some exciting momentum in the last few years. Nigeria’s 2023 general elections amplified the usage of social media and other online platforms as tools for electioneering campaigns, socio-political mobilizations and civic engagement. The study, therefore, focuses on transmedia and platformed political discourse as a new strategy to promote political candidates and their manifesto in order to mobilize support and woo voters. This innovative transmedia digital discourse model involves a constellation of online texts and images transmitted through different online platforms almost simultaneously. The data for the study was extracted from the 2023 general elections campaigns in Nigeria between January- March 2023 through media monitoring, manual download and the use of software to harvest the online electioneering campaign material. I adopted a discursive-analytic qualitative technique with toolkits drawn from a computer-mediated multimodal discourse paradigm. The study maps the progressive development of digital political discourse in this young democracy. The findings also demonstrate the inevitable transformation of modern democratic practice through platform-dependent and transmedia political discourse. Political actors and media practitioners now deploy layers of social media network platforms to convey messages and mobilize supporters in order to aggregate and maximize the impact of their media campaign projects and audience reach.

Keywords: social media, digital humanities, political discourse, platformized discourse, multimodal discourse

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Authors: R. A. Abdel Rahman, A. E. Abdel Wahab, E. A. Goghneimy, H. F. Mohamed, E. M. Salama

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Infectious diseases are a major cause of death worldwide. The treatment of infections continues to be problematic in modern time because of the severe side effects of some drugs and the growing resistance to antimicrobial agents. Hence, the search for newer, safer and more potent antimicrobials is a pressing need. Herbal medicines have received much attention as a source of new antibacterial drugs since they are considered time-tested and comparatively safe both for human use and the environment. In the present study, the antimicrobial activity of marjoram (Origanum majorana L.) essential oil on some gram positive and gram negative reference bacteria, as well as some hospital resistant microbes, was tested. Marjoram oil was extracted and the oil chemical constituents were identified using GC/MS analysis. Staphylococcus aureas ATCC 6923, Pseudomonus auregonosa ATCC 9027, Bacillus subtilis ATCC 6633, E. coli ATCC 8736 and two hospital resistant microbes isolates 16 and 21 were used. The two isolates were identified by biochemical tests and 16s rRNA as proteus spp. and Enterococcus facielus. The effect of different concentrations of essential oils on bacterial growth was tested using agar disk diffusion assay method to determine the minimum inhibitory concentrations and using micro dilution method to determine the minimum bactericidal concentrations. Marjoram oil was found to be effective against both reference and hospital resistance strains. Hospital strains were more resistant to marjoram oil than reference strains. P. auregonosa growth was completely inhibited at a low concentration of oil (4µl/ml). The other reference strains showed sensitivity to marjoram oil at concentrations ranged from 5 to 7µl/ml. The two hospital strains showed sensitivity at media containing 10 and 15µl/ml oil. The major components of oil were terpineol, cis-beta (23.5%), 1,6 – octadien –3-ol,3,7-dimethyl, 2 aminobenzoate (10.9%), alpha terpieol (8.6%) and linalool (6.3%). Scanning electron microscope (SEM) and transmission electron microscope (TEM) analysis were used to determine the difference between treated and untreated hospital strains. SEM results showed that treated cells were smaller in size than control cells. TEM data showed that cell lysis has occurred to treated cells. Treated cells have ruptured cell wall and appeared empty of cytoplasm compared to control cells which shown to be intact with normal volume of cytoplasm. The results indicated that marjoram oil has a positive antimicrobial effect on hospital resistance microbes. Natural crude extracts can be perfect resources for new antimicrobial drugs.

Keywords: antimicrobial activity, essential oil, hospital resistance microbes, marjoram

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Authors: Ahmad Kayvani Fard, Gordon Mckay, Muataz Hussien

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Adsorption/sorption is believed to be one of the optimal processes for the removal of heavy metals from water due to its low operational and capital cost as well as its high removal efficiency. Different materials have been reported in literature as adsorbent for heavy metal removal in waste water such as natural sorbents, organic polymers (synthetic) and mineral materials (inorganic). The selection of adsorbents and development of new functional materials that can achieve good removal of heavy metals from water is an important practice and depends on many factors, such as the availability of the material, cost of material, and material safety and etc. In this study we reported the synthesis of doped Activated carbon and Carbon nanotube (CNT) with different loading of metal oxide nanoparticles such as Fe2O3, Fe3O4, Al2O3, TiO2, SiO2 and Ag nanoparticles and their application in removal of heavy metals, hydrocarbon, and organics from waste water. Commercial AC and CNT with different loadings of mentioned nanoparticle were prepared and effect of pH, adsorbent dosage, sorption kinetic, and concentration effects are studied and optimum condition for removal of heavy metals from water is reported. The prepared composite sorbent is characterized using field emission scanning electron microscopy (FE-SEM), high transmission electron microscopy (HR-TEM), thermogravimetric analysis (TGA), X-ray diffractometer (XRD), the Brunauer, Emmett and Teller (BET) nitrogen adsorption technique, and Zeta potential. The composite materials showed higher removal efficiency and superior adsorption capacity compared to commercially available carbon based adsorbent. The specific surface area of AC increased by 50% reaching up to 2000 m2/g while the CNT specific surface area of CNT increased by more than 8 times reaching value of 890 m2/g. The increased surface area is one of the key parameters along with surface charge of the material determining the removal efficiency and removal efficiency. Moreover, the surface charge density of the impregnated CNT and AC have enhanced significantly where can benefit the adsorption process. The nanoparticles also enhance the catalytic activity of material and reduce the agglomeration and aggregation of material which provides more active site for adsorbing the contaminant from water. Some of the results for treating wastewater includes 100% removal of BTEX, arsenic, strontium, barium, phenolic compounds, and oil from water. The results obtained are promising for the use of AC and CNT loaded with metal oxide nanoparticle in treatment and pretreatment of waste water and produced water before desalination process. Adsorption can be very efficient with low energy consumption and economic feasibility.

Keywords: carbon nanotube, activated carbon, adsorption, heavy metal, water treatment

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Authors: Hana Al-Baghaoi, Kumar Shiva Gubbiyappa, Mayuren Candasamy, Kiruthiga Perumal Vijayaraman

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Acne is a chronic inflammatory disease of the sebaceous glands characterized by areas of skin with seborrhea, comedones, papules, pustules, nodules, and possibly scarring. Propionibacterium acnes (P. acnes), plays a key role in the pathogenesis of acne. Their colonization and proliferation trigger the host’s inflammatory response leading to the production of pro-inflammatory cytokines such as interleukin-8 (IL-8) and tumour necrosis factor-α (TNF-α). The usage of honey and natural compounds to treat skin ailments has strong support in the current trend of drug discovery. The present study was carried out evaluate antimicrobial and anti-inflammatory potential of Doani Sidr honey and its fractions against P. acnes and to screen madecassoside alone and in combination with fractions of honey. The broth dilution method was used to assess the antibacterial activity. Also, ultra structural changes in cell morphology were studied before and after exposure to Sidr honey using transmission electron microscopy (TEM). The three non-toxic concentrations of the samples were investigated for suppression of cytokines IL 8 and TNF α by testing the cell supernatants in the co-culture of the human peripheral blood mononuclear cells (hPBMCs) heat killed P. acnes using enzyme immunoassay kits (ELISA). Results obtained was evaluated by statistical analysis using Graph Pad Prism 5 software. The Doani Sidr honey and polysaccharide fractions were able to inhibit the growth of P. acnes with a noteworthy minimum inhibitory concentration (MIC) value of 18% (w/v) and 29% (w/v), respectively. The proximity of MIC and MBC values indicates that Doani Sidr honey had bactericidal effect against P. acnes which is confirmed by TEM analysis. TEM images of P. acnes after treatment with Doani Sidr honey showed completely physical membrane damage and lysis of cells; whereas non honey treated cells (control) did not show any damage. In addition, Doani Sidr honey and its fractions significantly inhibited (> 90%) of secretion of pro-inflammatory cytokines like TNF α and IL 8 by hPBMCs pretreated with heat-killed P. acnes. However, no significant inhibition was detected for madecassoside at its highest concentration tested. Our results suggested that Doani Sidr honey possesses both antimicrobial and anti-inflammatory effects against P. acnes and can possibly be used as therapeutic agents for acne. Furthermore, polysaccharide fraction derived from Doani Sidr honey showed potent inhibitory effect toward P. acnes. Hence, we hypothesize that fraction prepared from Sidr honey might be contributing to the antimicrobial and anti-inflammatory activity. Therefore, this polysaccharide fraction of Doani Sidr honey needs to be further explored and characterized for various phytochemicals which are contributing to antimicrobial and anti-inflammatory properties.

Keywords: Doani sidr honey, Propionibacterium acnes, IL-8, TNF alpha

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Authors: Yogita Patil-Sen

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Superparamagnetic Iron Oxide Nanoparticles (SPIONs) have become increasingly important materials for separation of specific bio-molecules, drug delivery vehicle, contrast agent for MRI and magnetic hyperthermia for cancer therapy. Hyperthermia is emerging as an alternative cancer treatment to the conventional radio- and chemo-therapy, which have harmful side effects. When subjected to an alternating magnetic field, the magnetic energy of SPIONs is converted into thermal energy due to movement of particles. The ability of SPIONs to generate heat and potentially kill cancerous cells, which are more susceptible than the normal cells to temperatures higher than 41 °C forms the basis of hyerpthermia treatement. The amount of heat generated depends upon the magnetic properties of SPIONs which in turn is affected by their properties such as size and shape. One of the main problems associated with SPIONs is particle aggregation which limits their employability in in vivo drug delivery applications and hyperthermia cancer treatments. Coating the iron oxide core with thermally responsive lipid based nanostructures tend to overcome the issue of aggregation as well as improve biocompatibility and can enhance drug loading efficiency. Herein we report suitability of SPIONs and silica coated core-shell SPIONs, which are further, coated with various lipids for drug delivery and magnetic hyperthermia applications. The synthesis of nanoparticles is carried out using the established methods reported in the literature with some modifications. The nanoparticles are characterised using Infrared spectroscopy (IR), X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and Vibrating Sample Magnetometer (VSM). The heating ability of nanoparticles is tested under alternating magnetic field. The efficacy of the nanoparticles as drug carrier is also investigated. The loading of an anticancer drug, Doxorubicin at 18 °C is measured up to 48 hours using UV-visible spectrophotometer. The drug release profile is obtained under thermal incubation condition at 37 °C and compared with that under the influence of alternating magnetic field. The results suggest that the nanoparticles exhibit superparamagnetic behaviour, although coating reduces the magnetic properties of the particles. Both the uncoated and coated particles show good heating ability, again it is observed that coating decreases the heating behaviour of the particles. However, coated particles show higher drug loading efficiency than the uncoated particles and the drug release is much more controlled under the alternating magnetic field. Thus, the results demonstrate that lipid coated SPIONs exhibit potential as drug delivery vehicles for magnetic hyperthermia based cancer therapy.

Keywords: drug delivery, hyperthermia, lipids, superparamagnetic iron oxide nanoparticles (SPIONS)

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Authors: Elizabeth O. Odewale, Sachithra T. Wanasinghe, Aaron S. Rury

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Cavity polaritons form when molecular excitons strongly couple to photons in carefully constructed optical cavities. These polaritons, which are hybrid light-matter states possessing a unique combination of photonic and excitonic properties, present the opportunity to manipulate the properties of various semiconductor materials. The systematic manipulation of materials through polariton formation could potentially improve the functionalities of many optoelectronic devices such as lasers, light-emitting diodes, photon-based quantum computers, and solar cells. However, the prospects of leveraging polariton formation for novel devices and device operation depend on more complete connections between the properties of molecular chromophores, and the hybrid light-matter states they form, which remains an outstanding scientific goal. Specifically, for most optoelectronic applications, it is paramount to understand how polariton formation affects the spectra of light absorbed by molecules coupled strongly to cavity photons. An essential feature of a polariton state is its dispersive energy, which occurs due to the enhanced spatial delocalization of the polaritons relative to bare molecules. To leverage the spatial delocalization of cavity polaritons, angle-resolved photoluminescence excitation spectroscopy was employed in characterizing light emission from the polaritonic states. Using lasers of appropriate energies, the polariton branches were resonantly excited to understand how molecular light absorption changes under different strong light-matter coupling conditions. Since an excited state has a finite lifetime, the photon absorbed by the polariton decays non-radiatively into lower-lying molecular states, from which radiative relaxation to the ground state occurs. The resulting fluorescence is collected across several angles of excitation incidence. By modeling the behavior of the light emission observed from the lower-lying molecular state and combining this result with the output of angle-resolved transmission measurements, inferences are drawn about how the behavior of molecules changes when they form polaritons. These results show how the intrinsic properties of molecules, such as the excitonic lifetime, affect the rate at which the polaritonic states relax. While it is true that the lifetime of the photon mediates the rate of relaxation in a cavity, the results from this study provide evidence that the lifetime of the molecular exciton also limits the rate of polariton relaxation.

Keywords: flourescece, molecules in cavityies, optical cavity, photoluminescence excitation, spectroscopy, strong coupling

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Authors: Ying-Jung Hsieh, Angela S. Huang, Chu-Ming Chiu, Yu-Min Chou, Chin-Hui Yang

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Background and Objectives: Hepatitis A is primarily acquired by the fecal-oral route through person-to-person contact or ingestion of contaminated food or water. During 2010 to 2014, an average of 83 cases of locally-acquired disease was reported to Taiwan’s notifiable disease system. Taiwan Centers for Disease Control (TCDC) identified an outbreak of acute hepatitis A which began in June 2015. Of the 126 cases reported in 2015, 103 (82%) cases were reported during June–December and 95 cases (92%) of them were male. The average age of all male cases was 31 years (median, 29 years; range, 15–76 years). Among the 95 male cases, 49 (52%) were also infected with HIV, and all reported to have had sex with other men. To control this outbreak, TCDC launched a free hepatitis A vaccination program in January 2016 for close contacts of confirmed hepatitis A cases, including family members, sexual partners, and household contacts. Effect of the vaccination program was evaluated. Methods: All cases of hepatitis A reported to the National Notifiable Disease Surveillance System were included. A case of hepatitis A was defined as a locally-acquired disease in a person who had acute clinical symptoms include fever, malaise, loss of appetite, nausea or abdominal discomfort compatible with hepatitis, and tested positive for anti-HAV IgM during June 2015 to June 2016 in Taiwan. The rate of case accumulation was calculated using a simple regression model. Results: During January–June 2016, there were 466 cases of hepatitis A reported; of the 243 (52%) who were also infected with HIV, 232 (95%) had a history of having sex with men. Of the 346 cases that were followed up, 259 (75%) provided information on contacts but only 14 (5%) of them provided the name of their sexual partners. Among the 602 contacts reported, 349 (58%) were family members, 14 (2%) were sexual partners, and 239 (40%) were other household contacts. Among the 602 contacts eligible for free hepatitis A vaccination, 440 (73%) received the vaccine. There were 87 (25%) cases that refused to disclose their close contacts. The average case accumulation rate during January–June 2016 was 21.7 cases per month, which was 6.8 times compared to the average case accumulation rate during June–December 2015 of 3.2 cases per month. Conclusions: Despite vaccination program aimed to provide free hepatitis A vaccine to close contacts of hepatitis A patients, the outbreak continued and even gained momentum in transmission. Refusal by hepatitis A patients to provide names of their close contacts and rejection of contacts to take the hepatitis A vaccine may have contributed to the poor effect of the program. Targeted vaccination efforts of all MSM may be needed to control the outbreak among this population in the short term. In the long term, universal vaccination program is needed to prevent the infection of hepatitis A.

Keywords: hepatitis A, HIV, men who have sex with men, vaccination

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Authors: Atitallah Sofien, Bouyahia Olfa, Romdhani Meriam, Missaoui Nada, Ben Rabeh Rania, Yahyaoui Salem, Mazigh Sonia, Boukthir Samir

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Introduction: Traditional medicine refers to a diverse range of therapeutic practices and knowledge systems that have been employed by different cultures over an extended period to uphold and rejuvenate health. These practices can involve herbal remedies, acupuncture, massage, and alternative healing methods that deviate from conventional medical approaches. In Tunisia, we often use unidentified utensils to scratch the oral cavity internally in infants in order to widen the oral cavity for better breathing and swallowing. However, these practices can be risky and may jeopardize the patients' prognosis or even their lives. Aim: This is the case of a nine-month-old infant, admitted to the pediatric department and subsequently to the intensive care unit due to a peritonsillar abscess following the utilization of an unidentifiable tool to scrape the interior of the oral cavity. Case Report: This is a 9-month-old infant with no particular medical history, admitted for high respiratory distress and a fever persisting for 4 days. On clinical examination, he had a respiratory rate of 70 cycles per minute with an oxygen saturation of 97% and subcostal retractions, along with a heart rate of 175 beats per minute. His white blood cell count was 40,960/mm³, and his C-reactive protein was 250 mg/L. Given the severity of the clinical presentation, the infant was transferred to the intensive care unit, intubated, and mechanically ventilated. A cervical-thoracic CT scan was performed, revealing a ruptured 18 mm left peritonsillar abscess in the oropharynx associated with cellulitis of the retropharyngeal space. The oto-rhino-laryngoscopic examination revealed an asymmetry involving the left lateral wall of the oropharynx with the presence of a fistula behind the posterior pillar. Dissection of the collection cavity was performed, allowing the drainage of 2 ml of pus. The culture was negative. The patient received cefotaxime in combination with metronidazole and gentamicin for a duration of 10 days, followed by a switch to amoxicillin-clavulanic acid for 7 days. The patient was extubated after 4 days of treatment, and the clinical and radiological progress was favorable. Conclusions: Traditional medicine remains risky due to the lack of scientific evidence and the potential for injuries and transmission of infectious diseases, especially in children, who constitute a vulnerable population. Therefore, parents should consult healthcare professionals and rely on evidence-based care.

Keywords: children, peritonsillar abscess, traditional medicine, respiratory distress

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Authors: Farha Ibrahim, Ely Zarina Samsudin, Ahmad Razali Ishak, Jeyanthini Sathasivam

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Introduction: Indoor air quality (IAQ) has recently gained substantial traction as the airborne transmission of infectious respiratory disease has become an increasing public health concern. Public hospital outpatient department (OPD). IAQ warrants special consideration as it is the most visited department in which patients and staff are all directly impacted by poor IAQ. However, there is limited evidence on IAQ in these settings. Moreover, occupants’ behavior like occupant’s movement and operation of door, windows and appliances, have been shown to significantly affect IAQ, yet the influence of these determinants on IAQ in such settings have not been established. Objectives: This study aims to examine IAQ in Malaysian public hospitals OPD and assess its relationships with occupants’ behavior. Methodology: A multicenter cross-sectional study in which stratified random sampling of Johor public hospitals OPD (n=6) according to building age was conducted. IAQ measurements include indoor air temperature, relative humidity (RH), air velocity (AV), carbon dioxide (CO2), total bacterial count (TBC) and total fungal count (TFC). Occupants’ behaviors in Malaysian public hospital OPD are assessed using observation forms, and results were analyzed. Descriptive statistics were performed to characterize all study variables, whereas non-parametric Spearman Rank correlation analysis was used to assess the correlation between IAQ and occupants’ behavior. Results: After adjusting for potential cofounder, the study has suggested that occupants’ movement in new building, like seated quietly, is significantly correlated with AV in new building (r 0.642, p-value 0.010), CO2 in new (r 0.772, p-value <0.001) and old building (r -0.559, p-value 0.020), TBC in new (r 0.747, p-value 0.001) and old building (r -0.559, p-value 0.020), and TFC in new (r 0.777, p-value <0.001) and old building (r -0.485, p-value 0.049). In addition, standing relaxed movement is correlated with indoor air temperature (r 0.823, p-value <0.001) in new building, CO2 (r 0.559, p-value 0.020), TBC (r 0.559, p-value 0.020), and TFC (r -0.485, p-value 0.049) in old building, while walking is correlated with AV in new building (r -0.642, p-value 0.001), CO2 in new (r -0.772, p-value <0.001) and old building (r 0.559, p-value 0.020), TBC in new (r -0.747, p-value 0.001) and old building (r 0.559, p-value 0.020), and TFC in old building (r -0.485, p-value 0.049). The indoor air temperature is significantly correlated with number of doors kept opened (r 0.522, p-value 0.046), frequency of door adjustments (r 0.753, p-value 0.001), number of windows kept opened (r 0.522, p-value 0.046), number of air-conditioned (AC) switched on (r 0.698, p-value 0.004) and frequency of AC adjustment (r 0.753, p-value 0.001) in new hospital OPD building. AV is found to be significantly correlated with number of doors kept opened (r 0.642, p-value 0.01), frequency of door adjustments (r 0.553, p-value 0.032), number of windows kept opened (r 0.642, p-value 0.01), and frequency of AC adjustment, number of fans switched on, and frequency of fans adjustment(all with r 0.553, p-value 0.032) in new building. In old hospital OPD building, the number of doors kept opened is significantly correlated with CO₂, TBC (both r -0.559, p-value 0.020) and TFC (r -0.495, p-value 0.049), frequency of door adjustment is significantly correlated with CO₂, TBC (both r-0.559, p-value 0.020) and TFC (r -0.495, p-value 0.049), number of windows kept opened is significantly correlated with CO₂, TBC (both r 0.559, p-value 0.020) and TFC (r 0.495, p-value 0.049), frequency of window adjustment is significantly correlated with CO₂,TBC (both r -0.559, p-value 0.020) and TFC (r -0.495, p-value 0.049), number of AC switched on is significantly correlated with CO₂, TBC (both r -0.559, p-value 0.020) and TFC (r -0.495, p-value 0.049),, frequency of AC adjustment is significantly correlated with CO2 (r 0.559, p-value 0.020), TBC (0.559, p-value 0.020) and TFC (r -0.495, p-value 0.049), number of fans switched on is significantly correlated with CO2, TBC (both r 0.559, p-value 0.020) and TFC (r 0.495, p-value 0.049), and frequency of fans adjustment is significantly correlated with CO2, TBC (both r -0.559, p-value 0.020) and TFC (r -0.495, p-value 0.049). Conclusion: This study provided evidence on IAQ parameters in Malaysian public hospitals OPD and significant factors that may be effective targets of prospective intervention, thus enabling stakeholders to develop appropriate policies and programs to mitigate IAQ issues in Malaysian public hospitals OPD.

Keywords: outpatient department, iaq, occupants practice, public hospital

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Authors: Cao Bin, Yuan Yi, Wang Qiang, Amor Abdelkader, Ali Reza Kamali, Diogo Montalvão

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The study of the electrodynamic behavior of non-ferrous particles in time-varying magnetic fields is a promising area of research with wide applications, including recycling of non-ferrous metals, mechanical transmission, and space debris. The key technology for recovering non-ferrous metals is eddy current separation (ECS), which utilizes the eddy current force and torque to separate non-ferrous metals. ECS has several advantages, such as low energy consumption, large processing capacity, and no secondary pollution, making it suitable for processing various mixtures like electronic scrap, auto shredder residue, aluminum scrap, and incineration bottom ash. Improving the separation efficiency of mixtures with different particle sizes in ECS can create significant social and economic benefits. Our previous study investigated the influence of particle size on separation efficiency by combining numerical simulations and separation experiments. Pearson correlation analysis found a strong correlation between the eddy current force in simulations and the repulsion distance in experiments, which confirmed the effectiveness of our simulation model. The interaction effects between particle size and material type, rotational speed, and magnetic pole arrangement were examined. It offer valuable insights for the design and optimization of eddy current separators. The underlying mechanism behind the effect of particle size on separation efficiency was discovered by analyzing eddy current and field gradient. The results showed that the magnitude and distribution heterogeneity of eddy current and magnetic field gradient increased with particle size in eddy current separation. Based on this, we further found that increasing the curvature of magnetic field lines within particles could also increase the eddy current force, providing a optimized method to improving the separation efficiency of fine particles. By combining the results of the studies, a more systematic and comprehensive set of optimization guidelines can be proposed for mixtures with different particle size ranges. The separation efficiency of fine particles could be improved by increasing the rotational speed, curvature of magnetic field lines, and electrical conductivity/density of materials, as well as utilizing the eddy current torque. When designing an ECS, the particle size range of the target mixture should be investigated in advance, and the suitable parameters for separating the mixture can be fixed accordingly. In summary, these results can guide the design and optimization of ECS, and also expand the application areas for ECS.

Keywords: eddy current separation, particle size, numerical simulation, metal recovery

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Authors: S. M. Mabandla, P. Loveday, C. Gomes, D. T. Maiga, T. T. Phadi

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Lead zirconate titanate (PZT) piezoelectric ceramics are widely used in ultrasonic applications due to their ability to effectively convert electrical energy into mechanical vibrations and vice versa. This paper presents a study on the behaviour of various combinations of pairs of PZT piezoelectric ceramic materials positioned adjacent to each other with an intermediate gap submerged in water, where one piezoelectric ceramic material is excited by a cyclic electric field with constant frequency and amplitude displacement. The transmitted ultrasonic sound propagates through the medium and is received by the PZT ceramic at the other end, the ultrasonic sound signal amplitude displacement experiences attenuation during propagation due to acoustic impedance. The investigation focuses on understanding the causes of extremely high amplitude displacement attenuation that have been observed in various combinations of piezoelectric ceramic pairs that are submerged in water arranged in a manner stipulated earlier. by examining various combinations of pairs of these piezoelectric ceramics, their physical, electrical, and acoustic properties, and behaviour and attributing them to the observed significant signal attenuation. The experimental setup involves exciting one piezoelectric ceramic material at one end with a burst square cyclic electric field signal of constant frequency, which generates a burst of ultrasonic sound that propagates through the water medium to the adjacent piezoelectric ceramic at the other end. Mechanical vibrations of a PZT piezoelectric ceramic are measured using a double-beam laser Doppler vibrometer to mimic the incident ultrasonic waves generated and received ultrasonic waves on the other end due to mechanical vibrations of a PZT. The measured ultrasonic sound wave signals are continuously compared to the applied cyclic electric field at both ends. The impedance matching networks are continuously tuned at both ends to eliminate electromechanical impedance mismatch to improve ultrasonic transmission and reception. The study delves into various physical, electrical, and acoustic properties of the PZT piezoelectric ceramics, such as the electromechanical coupling factor, acoustic coupling, and elasticity, among others. These properties are analyzed to identify potential factors contributing to the unusually high acoustic impedance in the water medium between the ceramics. Additionally, impedance-matching networks are investigated at both ends to offset the high signal attenuation and improve overall system performance. The findings will be reported in this paper.

Keywords: acoustic impedance, impedance mismatch, piezoelectric ceramics, ultrasonic sound

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Authors: Hela Ghali, Sihem Ben Fredj, Mohamed Ben Rejeb, Sawssen Layouni, Salwa Khefacha, Lamine Dhidah, Houyem Said Laatiri

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Background: Antimicrobial resistance is a growing threat to public health and motivates to improve prevention and control programs both at international (WHO) and national levels. Despite their low pathogenicity, vancomycin-resistant enterococci (VRE) are common nosocomial pathogens in several countries. The high potential for transmission of VRE between patients and the threat to send its resistance genes to other bacteria such as staphylococcus aureus already resistant to meticilin, justify strict control measures. Indeed, in Europe, the proportion of Enterococcus faecium responsible for invasive infections, varies from 1% to 35% in 2011 and less than 5% were resistant to vancomycin. In addition, it represents the second cause of urinary tract and wound infections and the third cause of nosocomial bacteremia in the United States. The nosocomial outbreaks of VRE have been mainly described in intensive care services, hematology-oncology and haemodialysis. An epidemic of VRE has affected our hospital and the objective of this work is to describe the measures put in place. Materials/Methods: Following the alert given by the service of plastic surgery concerning a patient carrier of VRE, a team of the prevention and healthcare security service (doctor + technician) made an investigation. A review of files was conducted to draw the synoptic table and the table of cases. Results: By contacting the microbiology laboratory, we have identified four other cases of VRE and who were hospitalized in Medical resuscitation department (2 cases, one of them was transferred to the Physical rehabilitation department), and Nephrology department (2 cases). The visit has allowed to detect several malfunctions in professional practice. A crisis cell has allowed to validate, coordinate and implement control measures following the recommendations of the Technical Center of nosocomial infections. In fact, the process was to technically isolate cases in their sector of hospitalization, to restrict the use of antibiotics, to strength measures of basic hygiene, and to make a screening by rectal swab for both cases and contacts (other patients and health staff). These measures have helped to control the situation and no other case has been reported for a month. 2 new cases have been detected in the intensive care unit after a month. However, these are short-term strategies, and other measures in the medium and long term should be taken into account in order to face similar outbreaks. Conclusion: The efforts to control the outbreak were not efficient since 2 new cases have been reported after a month. Therefore, a continuous monitoring in order to detect new cases earlier is crucial to minimize the dissemination of VRE.

Keywords: hospitals, nosocomial infection, outbreak, vancomycin-resistant enterococci

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Authors: Ziyad S. Haidar

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Background: Saliva plays a major role in maintaining oral, dental, and general health and well-being; where it normally bathes the oral cavity acting as a clearing agent. This becomes more apparent when the amount and quality of saliva are significantly reduced due to medications, salivary gland neoplasms, disorders such as Sjögren’s syndrome, and especially ionizing radiation therapy for tumors of the head and neck, the 5th most common malignancy worldwide, during which the salivary glands are included within the radiation field/zone. Clinically, patients affected by salivary gland dysfunction often opt to terminate their radiotherapy course prematurely as they become malnourished and experience a significant decrease in their QoL. Accordingly, the formulation of a radio-protection/-prevention modality and development of an alternative Rx to restore damaged salivary gland tissue is eagerly awaited and highly desirable. Objectives: Assess the pre-clinical radio-protective effect and reparative/regenerative potential of layer-by-layer self-assembled lipid-polymer-based core-shell nanocapsules designed and fine-tuned for the sequential (ordered) release of dual cytokines, following a single local administration (direct injection) into a murine sub-mandibular salivary gland model of irradiation. Methods: The formulated core-shell nanocapsules were characterized by physical-chemical-mechanically pre-/post-loading with the drugs, followed by optimizing the pharmaco-kinetic profile. Then, nanosuspensions were administered directly into the salivary glands, 24hrs pre-irradiation (PBS, un-loaded nanocapsules, and individual and combined vehicle-free cytokines were injected into the control glands for an in-depth comparative analysis). External irradiation at an elevated dose of 18Gy was exposed to the head-and-neck region of C57BL/6 mice. Salivary flow rate (un-stimulated) and salivary protein content/excretion were regularly assessed using an enzyme-linked immunosorbent assay (3-month period). Histological and histomorphometric evaluation and apoptosis/proliferation analysis followed by local versus systemic bio-distribution and immuno-histochemical assays were then performed on all harvested major organs (at the distinct experimental end-points). Results: Monodisperse, stable, and cytocompatible nanocapsules capable of maintaining the bioactivity of the encapsulant within the different compartments with the core and shell and with controlled/customizable pharmaco-kinetics, resulted, as is illustrated in the graphical abstract (Figure) below. The experimental animals demonstrated a significant increase in salivary flow rates when compared to the controls. Herein, salivary protein content was comparable to the pre-irradiation (baseline) level. Histomorphometry further confirmed the biocompatibility and localization of the nanocapsules, in vivo, into the site of injection. Acinar cells showed fewer vacuoles and nuclear aberration in the experimental group, while the amount of mucin was higher in controls. Overall, fewer apoptotic activities were detected by a Terminal deoxynucleotidyl Transferase (TdT) dUTP Nick-End Labeling (TUNEL) assay and proliferative rates were similar to the controls, suggesting an interesting reparative and regenerative potential of irradiation-damaged/-dysfunctional salivary glands. The Figure below exemplifies some of these findings. Conclusions: Biocompatible, reproducible, and customizable self-assembling layer-by-layer core-shell delivery system is formulated and presented. Our findings suggest that localized sequential bioactive delivery of dual cytokines (in specific dose and order) can prevent irradiation-induced damage via reducing apoptosis and also has the potential to promote in situ proliferation of salivary gland cells; maxSALIVA is scalable (Good Manufacturing Practice or GMP production for human clinical trials) and patent-pending.

Keywords: cancer, head and neck, oncology, drug development, drug delivery systems, nanotechnology, nanoncology

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Authors: Tatyana Savchuk, Yelena Grinvald, Mohamed Ali, Ramune Sepetiene, Dinara Sadvakassova, Saniya Saussakova, Kuralay Zhangazieva, Dulat Imashpayev

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Introduction. The problem of viral hepatitis B (HBV) takes a vital place in the global health system. The existing risk of HBV transmission through blood transfusions is associated with transfusion of blood taken from infected individuals during the “serological window” period or from patients with latent HBV infection, the marker of which is anti-HBcore. In the absence of information about other markers of hepatitis B, the presence of anti-HBcore suggests that a person may be actively infected or has suffered hepatitis B in the past and has immunity. Aim. To study the risk factors influencing the positive anti-HBcore indicators among the donor population. Materials and Methods. The study was conducted in 2021 in the Scientific and Production Center of Transfusiology of the Ministry of Healthcare in Kazakhstan. The samples taken from blood donors were tested for anti-HBcore, by CLIA on the Architect i2000SR (ABBOTT). A special questionnaire was developed for the blood donors’ socio-demographic characteristics. Statistical analysis was conducted by the R software (version 4.1.1, USA, 2021). Results.5709 people aged 18 to 66 years were included in the study, the proportion of men and women was 68.17% and 31.83%, respectively. The average age of the participants was 35.7 years. A weighted multivariable mixed effects logistic regression analysis showed that age (p<0.001), ethnicity (p<0.05), and marital status (p<0.05) were statistically associated with anti-HBcore positivity. In particular, analysis adjusting for gender, nationality, education, marital status, family history of hepatitis, blood transfusion, injections, and surgical interventions, with a one-year increase in age (adjOR=1.06, 95%CI:1.05-1.07), showed an 6% growth in odds of having anti-HBcore positive results. Those who were russian ethnicity (adjOR=0.65, 95%CI:0.46-0.93) and representatives of other nationality groups (adjOR=0.56, 95%CI:0.37-0.85) had lower odds of having anti-HBcore when compared to Kazakhs when controlling for other covariant variables. Among singles, the odds of having a positive anti-HBcore were lower by 29% (adjOR = 0.71, 95%CI:0.57-0.89) compared to married participants when adjusting for other variables. Conclusions.Kazakhstan is one of the countries with medium endemicity of HBV prevalence (2%-7%). Results of the study demonstrated the possibility to form a profile of risk factors (age, nationality, marital status). Taking into account the data, it is recommended to increase attention to donor questionnaires by adding leading questions and to improve preventive measures to prevent HBV. Funding. This research was supported by a grant from Abbott Laboratories.

Keywords: anti-HBcore, blood donor, donation, hepatitis B virus, occult hepatitis

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Authors: Mark Darius Juszczak

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While epistemology, as a sub-field of philosophy, is generally concerned with theoretical questions about the nature of knowledge, the explosion in digital media technologies has resulted in an exponential increase in the storage and transmission of human information. That increase has resulted in a particular non-linear dynamic – digital epistemological functions are radically altering how and what we know. Neither the rate of that change nor the consequences of it have been well studied or taken into account in developing state-level strategies for epistemological functions. At the current time, US Federal policy, like that of virtually all other countries, maintains, at the national state level, clearly defined boundaries between various epistemological agencies - agencies that, in one way or another, mediate the functional use of knowledge. These agencies can take the form of patent and trademark offices, national library and archive systems, departments of education, departments such as the FTC, university systems and regulations, military research systems such as DARPA, federal scientific research agencies, medical and pharmaceutical accreditation agencies, federal funding for scientific research and legislative committees and subcommittees that attempt to alter the laws that govern epistemological functions. All of these agencies are in the constant process of creating, analyzing, and regulating knowledge. Those processes are, at the most general level, epistemological functions – they act upon and define what knowledge is. At the same time, however, there are no high-level strategic epistemological directives or frameworks that define those functions. The only time in US history where a proxy state-level epistemological strategy existed was between 1961 and 1969 when the Kennedy Administration committed the United States to the Apollo program. While that program had a singular technical objective as its outcome, that objective was so technologically advanced for its day and so complex so that it required a massive redirection of state-level epistemological functions – in essence, a broad and diverse set of state-level agencies suddenly found themselves working together towards a common epistemological goal. This paper does not call for a repeat of the Apollo program. Rather, its purpose is to investigate the minimum structural requirements for a national state-level epistemological strategy in the United States. In addition, this paper also seeks to analyze how the epistemological work of the multitude of national agencies within the United States would be affected by such a high-level framework. This paper is an exploratory study of this type of framework. The primary hypothesis of the author is that such a function is possible but would require extensive re-framing and reclassification of traditional epistemological functions at the respective agency level. In much the same way that, for example, DHS (Department of Homeland Security) evolved to respond to a new type of security threat in the world for the United States, it is theorized that a lack of coordination and alignment in epistemological functions will equally result in a strategic threat to the United States.

Keywords: strategic security, epistemological functions, epistemological agencies, Apollo program

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Authors: David Edgar

Abstract:

To understand how the brain’s subconscious and conscious functions, we must conquer the physics of Unity, which leads to duality’s algorithm. Where the subconscious (bottom-up) and conscious (top-down) processes function together to produce and consume intelligence, we use terms like ‘time is relative,’ but we really do understand the meaning. In the brain, there are different processes and, therefore, different observers. These different processes experience time at different rates. A sensory system such as the eyes cycles measurement around 33 milliseconds, the conscious process of the frontal lobe cycles at 300 milliseconds, and the subconscious process of the thalamus cycle at 5 milliseconds. Three different observers experience time differently. To bridge observers, the thalamus, which is the fastest of the processes, maintains a synchronous state and entangles the different components of the brain’s physical process. The entanglements form a synchronous cohesion between the brain components allowing them to share the same state and execute in the same measurement cycle. The thalamus uses the shared state to control the firing sequence of the brain’s linear subconscious process. Sharing state also allows the brain to cheat on the amount of sensory data that must be exchanged between components. Only unpredictable motion is transferred through the synchronous state because predictable motion already exists in the shared framework. The brain’s synchronous subconscious process is entirely based on energy conservation, where prediction regulates energy usage. So, the eyes every 33 milliseconds dump their sensory data into the thalamus every day. The thalamus is going to perform a motion measurement to identify the unpredictable motion in the sensory data. Here is the trick. The thalamus conducts its measurement based on the original observation time of the sensory system (33 ms), not its own process time (5 ms). This creates a data payload of synchronous motion that preserves the original sensory observation. Basically, a frozen moment in time (Flat 4D). The single moment in time can then be processed through the single state maintained by the synchronous process. Other processes, such as consciousness (300 ms), can interface with the synchronous state to generate awareness of that moment. Now, synchronous data traveling through a separate faster synchronous process creates a theoretical time tunnel where observation time is tunneled through the synchronous process and is reproduced on the other side in the original time-relativity. The synchronous process eliminates time dilation by simply removing itself from the equation so that its own process time does not alter the experience. To the original observer, the measurement appears to be instantaneous, but in the thalamus, a linear subconscious process generating sensory perception and thought production is being executed. It is all just occurring in the time available because other observation times are slower than thalamic measurement time. For life to exist in the physical universe requires a linear measurement process, it just hides by operating at a faster time relativity. What’s interesting is time dilation is not the problem; it’s the solution. Einstein said there was no universal time.

Keywords: neural synchronization, natural intelligence, 99.95% IoT data transmission savings, artificial subconscious intelligence (ASI)

Procedia PDF Downloads 126

Authors: Görkem Cemali̇, Avram Aruh, Gamze Torun Köse, Erde Can ŞAfak

Abstract:

In order to heal bone disorders, the conventional methods which involve the use of autologous and allogenous bone grafts or permanent implants have certain disadvantages such as limited supply, disease transmission, or adverse immune response. A biodegradable material that acts as structural support to the damaged bone area and serves as a scaffold that enhances bone regeneration and guides bone formation is one desirable solution. Poly(propylene fumarate) (PPF) which is an unsaturated polyester that can be copolymerized with appropriate vinyl monomers to give biodegradable network structures, is a promising candidate polymer to prepare bone tissue engineering scaffolds. In this study, hydroxyl-terminated PPF was synthesized and thermally cured with vinyl phosphonic acid (VPA) and diethyl vinyl phosphonate (VPES) in the presence of radical initiator benzoyl peroxide (BP), with changing co-monomer weight ratios (10-40wt%). In addition, the synthesized PPF was cured with VPES comonomer at body temperature (37oC) in the presence of BP initiator, N, N-Dimethyl para-toluidine catalyst and varying amounts of Beta-tricalcium phosphate (0-20 wt% ß-TCP) as filler via radical polymerization to prepare composite materials that can be used in injectable forms. Thermomechanical properties, compressive properties, hydrophilicity and biodegradability of the PPF/VPA and PPF/VPES copolymers were determined and analyzed with respect to the copolymer composition. Biocompatibility of the resulting polymers and their composites was determined by the MTS assay and osteoblast activity was explored with von kossa, alkaline phosphatase and osteocalcin activity analysis and the effects of VPA and VPES comonomer composition on these properties were investigated. Thermally cured PPF/VPA and PPF/VPES copolymers with different compositions exhibited compressive modulus and strength values in the wide range of 10–836 MPa and 14–119 MPa, respectively. MTS assay studies showed that the majority of the tested compositions were biocompatible and the overall results indicated that PPF/VPA and PPF/VPES network polymers show significant potential for applications as bone tissue engineering scaffolds where varying PPF and co-monomer ratio provides adjustable and controllable properties of the end product. The body temperature cured PPF/VPES/ß-TCP composites exhibited significantly lower compressive modulus and strength values than the thermal cured PPF/VPES copolymers and were therefore found to be useful as scaffolds for cartilage tissue engineering applications.

Keywords: biodegradable, bone tissue, copolymer, poly(propylene fumarate), scaffold

Procedia PDF Downloads 166

Authors: Sudhir Kumar, V. R. Sinha

Abstract:

Background: The topical and systemic toxicity associated with present nonmelanoma skin cancer (NMSC) treatment therapy using 5-Fluorouracil (5-FU) make it necessary to develop a novel delivery system having lesser toxicity and better control over drug release. Solid lipid nanoparticles offer many advantages like: controlled and localized release of entrapped actives, nontoxicity, and better tolerance. Aim:-To investigate safety and efficacy of 5-FU loaded solid lipid nanoparticles as a topical delivery system for the treatment of nonmelanoma skin cancer. Method: Topical solid lipid nanoparticles of 5-FU were prepared using Compritol 888 ATO (Glyceryl behenate) as lipid component and pluronic F68 (Poloxamer 188), Tween 80 (Polysorbate 80), Tyloxapol (4-(1,1,3,3-Tetramethylbutyl) phenol polymer with formaldehyde and oxirane) as surfactants. The SLNs were prepared with emulsification method. Different formulation parameters viz. type and ratio of surfactant, ratio of lipid and ratio of surfactant:lipid were investigated on particle size and drug entrapment efficiency. Results: Characterization of SLNs like–Transmission Electron Microscopy (TEM), Differential Scannig calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), Particle size determination, Polydispersity index, Entrapment efficiency, Drug loading, ex vivo skin permeation and skin retention studies, skin irritation and histopathology studies were performed. TEM results showed that shape of SLNs was spherical with size range 200-500nm. Higher encapsulation efficiency was obtained for batches having higher concentration of surfactant and lipid. It was found maximum 64.3% for SLN-6 batch with size of 400.1±9.22 nm and PDI 0.221±0.031. Optimized SLN batches and marketed 5-FU cream were compared for flux across rat skin and skin drug retention. The lesser flux and higher skin retention was obtained for SLN formulation in comparison to topical 5-FU cream, which ensures less systemic toxicity and better control of drug release across skin. Chronic skin irritation studies lacks serious erythema or inflammation and histopathology studies showed no significant change in physiology of epidermal layers of rat skin. So, these studies suggest that the optimized SLN formulation is efficient then marketed cream and safer for long term NMSC treatment regimens. Conclusion: Topical and systemic toxicity associated with long-term use of 5-FU, in the treatment of NMSC, can be minimized with its controlled release with significant drug retention with minimal flux across skin. The study may provide a better alternate for effective NMSC treatment.

Keywords: 5-FU, topical formulation, solid lipid nanoparticles, non melanoma skin cancer

Procedia PDF Downloads 517

Authors: Harmeet Pal Singh Dhooria, Deepinder Chinna, UPS Sidhu, Alok Jain

Abstract:

Serious infections caused by gram-negative bacteria are a significant cause of mortality and morbidity in the hospital setting. In acute care facilities like in intensive care units (ICUs), the intensity of antimicrobial use together with a population highly susceptible to infection, creates an environment, which facilitates both emergence and transmission of Extended Spectrum -lactamase (ESBL) producing Enterobacteriaceae species. The study was conducted in the Medical Intensive Care Unit (MICU) and the Pulmonary Critical Care Unit (PCCU) of the Department of Medicine, Dayanand Medical College and Hospital, Ludhiana, Punjab, India. Out of a total of 1108 samples of urine, blood and respiratory tract secretions received for culture and sensitivity analysis from Medical Intensive Care Unit and Pulmonary Critical Care Unit, a total of 170 isolates of Enterobacteriaceae species were obtained which were then included in our study. Out of these 170 isolates, confirmed ESBL production was seen in 116 (68.24%) cases. E.coli was the most common species isolated (56.47%) followed by Klebsiella (32.94%), Enterobacter (5.88%), Citrobacter (3.53%), Enterobacter (0.59%) and Morganella (0.59%) among the total isolates. The rate of ESBL production was more in Klebsiella (78.57%) as compared to E.coli (60.42%). ESBL producers were found to be significantly more common in patients with prior history of hospitalization, antibiotic use, and prolonged ICU stay. Also significantly increased the prevalence of ESBL related infections was observed in patients with a history of catheterization or central line insertion but not in patients with the history of intubation. Patients who had an underlying malignancy had significantly higher prevalence of ESBL related infections as compared to other co-morbid illnesses. A slightly significant difference in the rate of mortality/LAMA was observed in the ESBL producer versus the non-ESBL producer group. The rate of mortality/LAMA was significantly higher in the ESBL related UTI but not in the ESBL related respiratory tract and bloodstream infections. ESBL producing isolates had significantly higher rates of resistance to Cefepime and Piperacillin/Tazobactum, and to non β-lactum antibiotics like Amikacin and Ciprofloxacin. The level of resistance to Imipenem was lower as compared to other antibiotics. However, it was noted that ESBL producing isolates had higher levels of resistance to Imipenem as compared to non-ESBL producing isolates. Conclusion- The prevalence of ESBL producing organisms was found to be very high (68.24%) among Enterobacteriaceae isolates in our ICU setting as among other ICU care settings around the world.

Keywords: enterobacteriaceae, extended spectrum B-lactamase (ESBL), ICU, antibiotic resistance

Procedia PDF Downloads 276