Search results for: crystal report
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2900

Search results for: crystal report

2540 CuIn₃Se₅ Colloidal Nanocrystals and Its Ink-Coated Films for Photovoltaics

Authors: M. Ghali, M. Elnimr, G. F. Ali, A. M. Eissa, H. Talaat

Abstract:

CuIn₃Se₅ material is indexed as ordered vacancy compounds having excellent matching properties with CuInGaSe (CIGS) solar absorber layer. For example, the valence band offset of CuIn₃Se₅ with CIGS is nearly 0.3 eV, and the lattice mismatch is less than 1%, besides the absence of discontinuity in their conduction bands. Thus, CuIn₃Se₅ can work as a passivation layer for repelling holes from CIGS/CdS interface and hence to reduce the interface carriers recombination and consequently enhancing the efficiency of CIGS/CdS solar cells. Theoretically, it was reported earlier that an improvement in the efficiency of p-CIGS-based solar cell with a thin ~100 nm of n-CuIn₃Se₅ layer is expected. Recently, a reported experiment demonstrated significant improvement in the efficiency of Molecular Beam Epitaxy (MBE) grown CIGS solar cells from 13.4 to 14.5% via inserting a thin layer of MBE-grown Cu(In,Ga)₃Se₅ layer at the CdS/CIGS interface. It should be mentioned that CuIn₃Se₅ material in either bulk or thin film form, are usually fabricated by high vacuum physical vapor deposition techniques (e.g., three-source co-evaporation, RF sputtering, flash evaporation, and molecular beam epitaxy). In addition, achieving photosensitive films of n-CuIn₃Se₅ material is important for new hybrid organic/inorganic structures, where inorganic photo-absorber layer, with n-type conductivity, can form n–p junction with organic p-type material (e.g., conductive polymers). A detailed study of the physical properties of CuIn₃Se₅ is still necessary for better understanding of device operation and further improvement of solar cells performance. Here, we report on the low-cost synthesis of CuIn₃Se₅ material in nano-scale size, with an average diameter ~10nm, using simple solution-based colloidal chemistry. In contrast to traditionally grown bulk tetragonal CuIn₃Se₅ crystals using high Vacuum-based technology, our colloidal CuIn₃Se₅ nanocrystals show cubic crystal structure with a shape of nanoparticles and band gap ~1.33 eV. Ink-coated thin films prepared from these nanocrystals colloids; display n-type character, 1.26 eV band gap and strong photo-responsive behavior with incident white light. This suggests the potential use of colloidal CuIn₃Se₅ as an active layer in all-solution-processed thin film solar cells.

Keywords: nanocrystals, CuInSe, thin film, optical properties

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2539 Invisible Aircraft Using Plasma Display

Authors: C. Ramamoorthy, R. Ranga Raj

Abstract:

In olden days the Ramayana epic depicts the usage of invisible and fuel less aircraft named pushpavimana. The change of color in the reptile family chameleon paves way for the concept of color change phenomenon available in nature. In present scenario the aircrafts are visible so it is easily identified. So there are too many problems from the threatening. Research is still going on about this problem by using Liquid Crystal Display (LCD). Objective of this paper is to find much better to use the concept of invisible aircraft using plasma display through Couple Charged Device camera (CCD), which has a high resolution and can be used for many purposes like spying, defense, etc. Moreover it is cost wise cheap then, escaping the foe viewing.

Keywords: CCD camera, chameleon, invisible, plasma display

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2538 Nurse Schedule Problem in Mubarak Al Kabeer Hospital

Authors: Khaled Al-Mansour, Nawaf Esmael, Abdulaziz Al-Zaid, Mohammed Al Ateeqi, Ali Al-Yousfi, Sayed Al-Zalzalah

Abstract:

In this project we will create the new schedule of nurse according to the preference of them. We did our project in Mubarak Al Kabeer Hospital (in Kuwait). The project aims to optimize the schedule of nurses in Mubarak Al Kabeer Hospital. The schedule of the nurses was studied and understood well to do any modification for their schedule to make the nurses feel as much comfort as they are. First constraints were found to know what things we can change and what things we can’t, the hard constraints are the hospital and ministry policies where we can’t change anything about, and the soft constraints are things that make nurses more comfortable. Data were collected and nurses were interviewed to know what is more better for them. All these constraints and date have been formulated to mathematical equations. This report will first contain an introduction to the topic which includes details of the problem definition. It will also contain information regarding the optimization of a nurse schedule and its contents and importance; furthermore, the report will contain information about the data needed to solve the problem and how it was collected. The problem requires formulation and that is also to be shown. The methodology will be explained which will state what has already been done. We used the lingo software to find the best schedule for the nurse. The schedule has been made according to what the nurses prefer, and also took consideration of the hospital policy when we make the schedule.

Keywords: nurse schedule problem, Kuwait, hospital policy, optimization of schedules

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2537 The Role of Pulmonary Resection in Complicated Primary Pediatric Pulmonary Tuberculosis: An Evidence-Based Case Report

Authors: Hendra Wibowo, Suprayitno Wardoyo, Dhama Shinta

Abstract:

Introduction: Pediatric pulmonary tuberculosis (TB) incidence was increasing, with many undetected cases. In complicated TB, treatment should consist of returning pulmonary function, preventing further complications, and eliminating bacteria. Complicated TB management was still controversial, and surgery was one of the treatments that should be evaluated in accordance with its role in the treatment of complicated TB. Method: This study was an evidence-based case report. The database used for the literature search were Cochrane, Medline, Proquest, and ScienceDirect. Keywords for the search were ‘primary pulmonary tuberculosis’, ‘surgery’, ‘lung resection’, and ‘children’. Inclusion criteria were studies in English or Indonesian, with children under 18 years old as subject, and full-text articles available. The assessment was done according to Oxford Centre for evidence-based medicine 2011. Results: Six cohort studies were analyzed. Surgery was indicated for patients with complicated TB that were unresponsive towards treatment. It should be noted that the experiments were done before the standard WHO antituberculosis therapy was applied; thus, the result may be different from the current application. Conclusion: Currently, there was no guideline on pulmonary resection. However, surgery yielded better mortality and morbidity in children with complicated pulmonary TB.

Keywords: pediatric, pulmonary, surgery, therapy, tuberculosis

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2536 Case Report: Rare Case of Endometrial Stromal Sarcoma with Omental Metastasis in a 19-Year Old Girl

Authors: Mukurdipi Ray, Seema Singh

Abstract:

Extrauterine endometrial stromal sarcoma (ESS) is a rare entity and typified by delayed recurrence of primary ESS. Here, we present an unusual case of uterine ESS in a woman with a history of hysterectomy. A 19-year-old girl, underwent a hysterectomy and bilateral salpingo-oophorectomy for uterine ESS 12 months ago and now after remaining disease free for nine months ago she presented with ascites along with pelvic and peritoneal mass. Intraoperatively, the large omental mass was found, and optimal cytoreduction with total omentomy (supracolic and infracolic ) total peritonectomy and hyperthermic intraperitoneal chemotherapy (HIPEC) was offered to the patient. Final histopathology report showed the involvement of only omentum by ESS cells. Immunohistochemistry (IHC) and receptor study were done and it was positive for CD-10 and desmin and negative for CK- 7. This case highlights the rarity of extrauterine ESS in the omentum with a known history of primary uterine ESS which was treated successfully with the above-mentioned procedure. Though active and long-term surveillance is recommended to monitor for late recurrences.

Keywords: endrometrial stromal sarcoma, complete cytoreduction, hyperthermic intra peritoneal chemotherapy, total omentectomy

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2535 Bilateral Choroidal Metastases as the Presenting Manifestation of Lung Adenocarcinoma in a Young, Non-smoking Female: A Case Report

Authors: Paras Agarwal

Abstract:

Background: Initially believed to be rare, metastases to the eye are the most common ocular malignancy. The choroid’s high perfusion rate not only makes it the most susceptible ocular site for tumour seeding, but also promotes its growth. The cancers most frequently responsible for choroidal metastases originate from the breast and lung, although a significant proportion have unidentified primaries at the time of presentation. Case Presentation: This case report describes a 34 year old female presenting to the ophthalmology department with a one month history of painless distorted vision. On fundus examination, she was noted to have bilateral choroidal lesionsand subsequently underwent a comprehensive diagnostic work-up. The patient was diagnosed with metastatic pulmonary adenocarcinoma, despite lacking conventional risk factors. As she was found to have a mutation in EGFR, the patient was commenced on tyrosine-kinase inhibition with afatinib. The choroidal lesions regressed with a significant improvement in visual acuity and a dramatic anatomical reduction of the choroidal masses. Conclusions: Our case demonstrates the importance of considering metastases as a differential diagnosis for choroidal lesions. Appropriate and thorough history-taking, examination and investigations may be required in order to deduce the underlying cause. Our case is unusual in view of the choroidal lesion being the primary manifestation of metastatic lung cancer in a young patient with no known risk factors. Early recognition of choroidal metastases is important as it is often the first sign of tumour dissemination and will prompt earlier treatment with systemic medications such as chemotherapy, immunotherapy, targeted therapy or hormonal therapy. Our case report also demonstrates the efficacy of afatinib for the treatment of choroidal metastases, with morphological and functional improvements observed with regard to the choroidal metastatic tumour.

Keywords: choroidal neoplasm, choroidal naevus, pulmonary adenocarcinoma, metastases, lung cancer

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2534 Application Research of Stilbene Crystal for the Measurement of Accelerator Neutron Sources

Authors: Zhao Kuo, Chen Liang, Zhang Zhongbing, Ruan Jinlu. He Shiyi, Xu Mengxuan

Abstract:

Stilbene, C₁₄H₁₂, is well known as one of the most useful organic scintillators for pulse shape discrimination (PSD) technique for its good scintillation properties. An on-line acquisition system and an off-line acquisition system were developed with several CAMAC standard plug-ins, NIM plug-ins, neutron/γ discriminating plug-in named 2160A and a digital oscilloscope with high sampling rate respectively for which stilbene crystals and photomultiplier tube detectors (PMT) as detector for accelerator neutron sources measurement carried out in China Institute of Atomic Energy. Pulse amplitude spectrums and charge amplitude spectrums were real-time recorded after good neutron/γ discrimination whose best PSD figure-of-merits (FoMs) are 1.756 for D-D accelerator neutron source and 1.393 for D-T accelerator neutron source. The probability of neutron events in total events was 80%, and neutron detection efficiency was 5.21% for D-D accelerator neutron sources, which were 50% and 1.44% for D-T accelerator neutron sources after subtracting the background of scattering observed by the on-line acquisition system. Pulse waveform signals were acquired by the off-line acquisition system randomly while the on-line acquisition system working. The PSD FoMs obtained by the off-line acquisition system were 2.158 for D-D accelerator neutron sources and 1.802 for D-T accelerator neutron sources after waveform digitization off-line processing named charge integration method for just 1000 pulses. In addition, the probabilities of neutron events in total events obtained by the off-line acquisition system matched very well with the probabilities of the on-line acquisition system. The pulse information recorded by the off-line acquisition system could be repetitively used to adjust the parameters or methods of PSD research and obtain neutron charge amplitude spectrums or pulse amplitude spectrums after digital analysis with a limited number of pulses. The off-line acquisition system showed equivalent or better measurement effects compared with the online system with a limited number of pulses which indicated a feasible method based on stilbene crystals detectors for the measurement of prompt neutrons neutron sources like prompt accelerator neutron sources emit a number of neutrons in a short time.

Keywords: stilbene crystal, accelerator neutron source, neutron / γ discrimination, figure-of-merits, CAMAC, waveform digitization

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2533 A Constructivist Approach and Tool for Autonomous Agent Bottom-up Sequential Learning

Authors: Jianyong Xue, Olivier L. Georgeon, Salima Hassas

Abstract:

During the initial phase of cognitive development, infants exhibit amazing abilities to generate novel behaviors in unfamiliar situations, and explore actively to learn the best while lacking extrinsic rewards from the environment. These abilities set them apart from even the most advanced autonomous robots. This work seeks to contribute to understand and replicate some of these abilities. We propose the Bottom-up hiErarchical sequential Learning algorithm with Constructivist pAradigm (BEL-CA) to design agents capable of learning autonomously and continuously through interactions. The algorithm implements no assumption about the semantics of input and output data. It does not rely upon a model of the world given a priori in the form of a set of states and transitions as well. Besides, we propose a toolkit to analyze the learning process at run time called GAIT (Generating and Analyzing Interaction Traces). We use GAIT to report and explain the detailed learning process and the structured behaviors that the agent has learned on each decision making. We report an experiment in which the agent learned to successfully interact with its environment and to avoid unfavorable interactions using regularities discovered through interaction.

Keywords: cognitive development, constructivist learning, hierarchical sequential learning, self-adaptation

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2532 First Report of Asiatic Black Bear: Evidence of Illegal Hunting and Trading from Manglawar Mountain, Swat, Pakistan

Authors: Waheed Akhtar

Abstract:

Bears in Asia facing multiple threats and challenges such as hunting, illegal trading, habitat loss, and human conflicts. According to IUCN Red List, the Asiatic black bear (Ursus thibetanus) is listed as Vulnerable since 1990, population declining by 49% during the last 30 years. The present study was conducted in Manglawar (DwaSaro Mountain) from April-August 2021, to collect all the information on Asiatic black bear observation, illegal hunting, and cub poaching. According to the response of the local community, very intensive illegal hunting and cub poaching were observed. Hunters usually installed many traps in the routes of black bears and when they move in the winter season the cubs get trapped and they collect them and kept in a specialized wooden box that is mainly helpful for further transportation. These cubs are then brought to the concerned Market where they sell them to many dealers. One of the potential observers of the illegal trading responds towards the Market price of the cubs, “The average price of the black bear cub is ranging from 45000-50000 Pakistani Rupees”. Apart from cubs' poaching, the black bear is also hunted for its skin, claws, and teeth.

Keywords: first report, illegal hunting, cub poaching, parts trading, Ursus thibetanus

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2531 Air Conditioner Refrigerant and Burn: A Case Report

Authors: Okan Cakir, Ibrahim Arziman, Derya Can, Mete Erkencigil, Murat Durusu, S. Mehmet Yasar

Abstract:

Introduction: Burn injuries from different types and ways commonly seen in emergency departments, approach and treatment varies from outpatient treatment to critical care unit. We wanted to mention a rare burn injury cause of air conditioner refrigerant. Case report: A 22-year-old case admitted to emergency department with a complaint of left hand burn injury and pain. In his history, he said that an accident was occurred before 30 minutes from admission while he had been trying to repair the air conditioner. Air conditioner refrigerant suddenly had erupted from its tank and burned his hand. In physical examination of extremities, second-degree burn bullae on the left hand on second and third proximal phalanx, between first and second phalanx palmar side and on hypothenar region and on third and fourth proximal phalanx and also hyperemia from hand to wrist were seen. There was no motor and sensorial deficiency. As a treatment, local silver sulfadiazine applied to the burn area and analgesic prescribed. The case called for the clinical follow-up to the plastic surgery department. Conclusion: The clinician should take a comprehensive and careful anamnesis for suitable and right management and treatment as in this case in which as well as rare and occurs different way.

Keywords: air conditioner refrigerant, burn, emergency department, rare

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2530 Abdominal Pregnancy with a Live Newborn in a Low Resource Setting: A Case Report

Authors: Olivier Mulisya, Guelord Barasima, Henry Mark Lugobe, Philémon Matumo, Bienfait Mumbere Vahwere, Hilaire Mutuka, Zawadi Léocadie, Wesley Lumika

Abstract:

Abdominal pregnancy is defined as pregnancy anywhere within the peritoneal cavity, exclusive of tubal, ovarian, or broad ligament locations. It is a rare form of ectopic pregnancy with high morbidity and mortality for both the mother and the fetus. Diagnosis can be frequently missed in most poor-resource settings because of poor antenatal coverage, low socioeconomic status in most of the patients as well as lack of adequate medical resources. Clinical diagnosis can be very difficult and an ultrasound scan is very helpful during the early stages of gestation but can also be disappointing in the later stages. We report a case of a 25-year-old woman with severe abdominal pain not amended with any medication. A clinical picture of shock lead to an emergency laparotomy which confirmed the diagnosis of abdominal pregnancy. The ministry of health in developing countries should make an effort to make routine early ultrasounds accessible to pregnant women, and obstetricians should keep in mind the possibility of ectopic pregnancy, irrespective of the gestational age.

Keywords: abdominal pregnancy, live new bron, ultrasound imaging, abdominal pain

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2529 Exchanging Radiology Reporting System with Electronic Health Record: Designing a Conceptual Model

Authors: Azadeh Bashiri

Abstract:

Introduction: In order to better designing of electronic health record system in Iran, integration of health information systems based on a common language must be done to interpret and exchange this information with this system is required. Background: This study, provides a conceptual model of radiology reporting system using unified modeling language. The proposed model can solve the problem of integration this information system with electronic health record system. By using this model and design its service based, easily connect to electronic health record in Iran and facilitate transfer radiology report data. Methods: This is a cross-sectional study that was conducted in 2013. The student community was 22 experts that working at the Imaging Center in Imam Khomeini Hospital in Tehran and the sample was accorded with the community. Research tool was a questionnaire that prepared by the researcher to determine the information requirements. Content validity and test-retest method was used to measure validity and reliability of questioner respectively. Data analyzed with average index, using SPSS. Also, Visual Paradigm software was used to design a conceptual model. Result: Based on the requirements assessment of experts and related texts, administrative, demographic and clinical data and radiological examination results and if the anesthesia procedure performed, anesthesia data suggested as minimum data set for radiology report and based it class diagram designed. Also by identifying radiology reporting system process, use case was drawn. Conclusion: According to the application of radiology reports in electronic health record system for diagnosing and managing of clinical problem of the patient, provide the conceptual Model for radiology reporting system; in order to systematically design it, the problem of data sharing between these systems and electronic health records system would eliminate.

Keywords: structured radiology report, information needs, minimum data set, electronic health record system in Iran

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2528 Structural and Electronic Properties of the Rock-salt BaxSr1−xS Alloys

Authors: B. Bahloul, K. Babesse, A. Dkhira, Y. Bahloul, L. Amirouche

Abstract:

Structural and electronic properties of the rock-salt BaxSr1−xS are calculated using the first-principles calculations based on the density functional theory (DFT) within the generalized gradient approximation (GGA), the local density approximation (LDA) and the virtual-crystal approximation (VCA). The calculated lattice parameters at equilibrium volume for x=0 and x=1 are in good agreement with the literature data. The BaxSr1−xS alloys are found to be an indirect band gap semiconductor. Moreoever, for the composition (x) ranging between [0-1], we think that our results are well discussed and well predicted.

Keywords: semiconductor, Ab initio calculations, rocksalt, band structure, BaxSr1−xS

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2527 Evaluation of the Implementation of Public Examination Chief Examiners’ Reports in Mathematics Curriculum Contents

Authors: Oginni Omoniyi Israel

Abstract:

This study evaluated the implementation of public examination Chief Examiners’ Reports (CER) in mathematics curriculum contents in Ekiti State Senior Secondary schools, Nigeria. The study adopted a descriptive research design of survey type. The sample consisted of 60 mathematics teachers and 120 students using a multi-stage sampling procedure. The instruments used were “Questionnaire on Teachers Implementation of Chief Examiners’ Report and Mathematics Curriculum Contents (QTICERMCC) and Questionnaire on Students Knowledge of Chief Examiners’ Report and Mathematics Curriculum Contents Implementation (SIERMCC)”. The validity of the instruments was carried out by experts, while the reliability coefficients of 0.85 and 0.87 were obtained through Cronbach’s Alpha formula. The data collected were analysed using descriptive and inferential statistics. The findings revealed that there was a significant relationship between awareness, availability, and accessibility of CER as well as mathematics curriculum contents. There was also a significant relationship in the implementation of CER in mathematics between teachers and students. Based on the findings, it was recommended that the examination bodies should organize an enlightment programme annually to create awareness of the utilization of CER among the stakeholders.

Keywords: evaluation, implementation, chief examiners’ reports, curriculum contents

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2526 Assessment of Knowledge, Attitude, and Practice of Health Care Professionals and Factors Associated with Adverse Drug Reaction Reporting in Public and Private Hospitals of Islamabad

Authors: Zaka Nisa, Farooq Sher

Abstract:

Adverse drug reactions (ADRs) underreporting is a great challenge to Pharmacovigilance. Health care professionals have to consider ADR reporting as their professional obligation, an effective system of ADR reporting is important to improve patient health care and safety. The present study is designed to assess the knowledge, attitude, practice and factors associated with ADR reporting by health care professionals (physicians and pharmacists) in public and private hospitals of Pakistan. A pretested questionnaire was administered to 384 physicians and pharmacists in public and private hospitals. Respondents were evaluated for their knowledge, attitude, and practice related to ADR reporting. The data was analyzed using the SPSS statistical software, the factors which encourage and discourage respondents in reporting ADRs were determined. Most of the respondents have shown a positive attitude towards ADR reporting. The response rate was 95.32%. Of the 367 questionnaires, including 333 (86.5%) physicians and 34 (8.8%) pharmacists with the mean age 28.34 (SD= 6.69), most of the respondents showed poor ADR reporting knowledge (83.1%). The majority of respondents (78.2%) showed positive attitude towards ADR reporting and only (12.3%) hospitals have good ADR reporting practice. Knowledge of respondents in public hospitals (8.6%) was less as compare to those in the private hospitals (29.7%) (P < 0.001). Attitude of respondents in private hospitals was more positive (92.4%) than those in public hospitals (68.8%) (P < 0.001). No significant difference was observed in practicing of ADR reporting in public (11.8%) and private hospitals (13.1%) (P value 0.89). Seriousness of ADR, unusualness of reaction, new drug involvement and confidence in diagnosis of ADR were the factors which encourage respondents to report ADR, however, lack of knowledge regarding where and how to report ADR, lack of access to ADR reporting form, managing patients was more important than reporting ADR, legal liability issues were the factors which discourage respondents to report ADR. The study reveals poor knowledge and practice regarding ADR reporting. However positive attitude was seen regarding ADR reporting. There is a need of educational training for health care professionals as well as genuine and continuous efforts are required by Government and health authorities to ensure the proper implementation of ADR reporting system in all of the hospitals.

Keywords: adverse drugs reactions (ADR), pharmacovigilance, spontaneous ADR reporting, knowledge of ADR, attitude of health care profesionals, practice of ADR reporting

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2525 Atypical Familial Amyotrophic Lateral Sclerosis Secondary to Superoxide Dismutase 1 Gene Mutation With Coexistent Axonal Polyneuropathy: A Challenging Diagnosis

Authors: Seraj Makkawi, Abdulaziz A. Alqarni, Himyan Alghaythee, Suzan Y. Alharbi, Anmar Fatani, Reem Adas, Ahmad R. Abuzinadah

Abstract:

Amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig's disease, is a neurodegenerative disease that involves both the upper and lower motor neurons. Familial ALS, including superoxide dismutase 1 (SOD1) mutation, accounts for 5-10% of all cases of ALS. Typically, the symptoms of ALS are purely motor, though coexistent sensory symptoms have been reported in rare cases. In this report, we describe the case of a 47- year-old man who presented with progressive bilateral lower limb weakness and numbness for the last four years. A nerve conduction study (NCS) showed evidence of coexistent axonal sensorimotor polyneuropathy in addition to the typical findings of ALS in needle electromyography. Genetic testing confirmed the diagnosis of familial ALS secondary to the SOD1 genetic mutation. This report highlights that the presence of sensory symptoms should not exclude the possibility of ALS in an appropriate clinical setting.

Keywords: Saudi Arabia, polyneuropathy, SOD1 gene mutation, familial amyotrophic lateral sclerosis, amyotrophic lateral sclerosis

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2524 Low Plastic Deformation Energy to Induce High Superficial Strain on AZ31 Magnesium Alloy Sheet

Authors: Emigdio Mendoza, Patricia Fernandez, Cristian Gomez

Abstract:

Magnesium alloys have generated great interest for several industrial applications because their high specific strength and low density make them a very attractive alternative for the manufacture of various components; however, these alloys present a limitation with their hexagonal crystal structure that limits the deformation mechanisms at room temperature likewise the molding components alternatives, it is for this reason that severe plastic deformation processes have taken a huge relevance recently because these, allow high deformation rates to be applied that induce microstructural changes where the deficiency in the sliding systems is compensated with crystallographic grains reorientations or crystal twinning. The present study reports a statistical analysis of process temperature, number of passes and shear angle with respect to the shear stress in severe plastic deformation process denominated 'Equal Channel Angular Sheet Drawing (ECASD)' applied to the magnesium alloy AZ31B through Python Statsmodels libraries, additionally a Post-Hoc range test is performed using the Tukey statistical test. Statistical results show that each variable has a p-value lower than 0.05, which allows comparing the average values of shear stresses obtained, which are in the range of 7.37 MPa to 12.23 MPa, lower values in comparison to others severe plastic deformation processes reported in the literature, considering a value of 157.53 MPa as the average creep stress for AZ31B alloy. However, a higher stress level is required when the sheets are processed using a shear angle of 150°, due to a higher level of adjustment applied for the shear die of 150°. Temperature and shear passes are important variables as well, but there is no significant impact on the level of stress applied during the ECASD process. In the processing of AZ31B magnesium alloy sheets, ECASD technique is evidenced as a viable alternative in the modification of the elasto-plastic properties of this alloy, promoting the weakening of the basal texture, which means, a better response to deformation, whereby, during the manufacture of parts by drawing or stamping processes the formation of cracks on the surface can be reduced, presenting an adequate mechanical performance.

Keywords: plastic deformation, strain, sheet drawing, magnesium

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2523 Plasmodium falciparum Infection and SARS-CoV-2 Immunoglobulin-G Positivity Rates Among Primary Healthcare Centre Attendees in Osogbo, Nigeria

Authors: Ojo Oo, Akinde S. B., Kiilani A. O., Jayeola Jo, Jogbodo T. M., Ajani Ka, Olaniyan So, Adeagbo Oy, Bolarinwa Ra, Durosomo Ha, Sule W. F.

Abstract:

Lockdown imposed to control SARS-CoV-2 transmission hampered malaria control services in Nigeria. Considering COVID-19 vaccination, we assessed Plasmodium falciparum (Pf) antigen and SARS-CoV-2 immunoglobulin-G (IgG) positivity among adults in Osogbo, Osun State, Nigeria. Consenting attendees of four Healthcare Centres were consecutively enrolled for blood sampling; relevant socio-demographic/behavioral/clinical/environmental data were collected with a questionnaire. Samples were tested, using commercial rapid test kits, for Pf antigen and SARS-CoV-2 IgG and results were analyzed using logistic regression. Participants' mean age was 40.99 years (n=200), and they were predominantly females (84.5%), traders/businessmen/women (86.0%), with self-reported receipt of COVID-19 vaccine from 123 (61.5%). Pf antigen positivity was 17.5% (95% CI: 12.23–22.77%) with age (p=0.004), marital status (p=0.004), report of stagnant water around the workplace (p=0.041) and bush around homes (p=0.008) being associated. SARS-CoV-2 IgG positivity was 56.5% (95% CI: 49.63–63.37%) with age (p=0.012) and receipt of COVID-19 vaccination (p=0.001) being associated. Although the vaccinated had a 22.8 times higher likelihood of IgG positivity, no factor was predictive of COVID-19 vaccine receipt. We report 17.5% Pf antigen positivity with four predictors, and 56.5% SARS-CoV-2 IgG positivity with two predictors.

Keywords: COVID-19, vaccine, IgG, Plasmodium falciparum, SARS-CoV-2

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2522 Associated Risks of Spontaneous Lung Collapse after Shoulder Surgery: A Literature Review

Authors: Fiona Bei Na Tan, Glen Wen Kiat Ho, Ee Leen Liow, Li Yin Tan, Sean Wei Loong Ho

Abstract:

Background: Shoulder arthroscopy is an increasingly common procedure. Pneumothorax post-shoulder arthroscopy is a rare complication. Objectives: Our aim is to highlight a case report of pneumothorax post shoulder arthroscopy and to conduct a literature review to evaluate the possible risk factors associated with developing a pneumothorax during or after shoulder arthroscopy. Case Report: We report the case of a 75-year-old male non-smoker who underwent left shoulder arthroscopy without regional anaesthesia and in the left lateral position. The general anaesthesia and surgery were uncomplicated. The patient was desaturated postoperatively and was found to have a pneumothorax on examination and chest X-ray. A chest tube drain was inserted promptly into the right chest. He had an uncomplicated postoperative course. Methods: PubMed Medline and Cochrane database search was carried out using the terms shoulder arthroplasty, pneumothorax, pneumomediastinum, and subcutaneous emphysema. We selected full-text articles written in English. Results: Thirty-two articles were identified and thoroughly reviewed. Based on our inclusion and exclusion criteria, 14 articles, which included 20 cases of pneumothorax during or after shoulder arthroscopy, were included. Eighty percent (16/20) of pneumothoraxes occurred postoperatively. In the articles that specify the side of pneumothorax, 91% (10/11) occur on the ipsilateral side of the arthroscopy. Eighty-eight percent (7/8) of pneumothoraxes occurred when subacromial decompression was performed. Fifty-six percent (9/16) occurred in patients placed in the lateral decubitus position. Only 30% (6/20) occurred in current or ex-smokers, and only 25% (5/20) had a pre-existing lung condition. Overall, of the articles that posit a mechanism, 75% (9/12) deem the pathogenesis to be multifactorial. Conclusion: The exact mechanism of pneumothorax is currently unknown. Awareness of this complication and timely recognition are important to prevent life-threatening sequelae. Surgeons should have a low threshold to obtain diagnostic plain radiographs in the event of clinical suspicion.

Keywords: rotator cuff repair, decompression, pressure, complication

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2521 Minimal Incision Cochlear Implantation in Congenital Abnormality: A Case Report

Authors: Munish Saroch, Amit Saini

Abstract:

Introduction: Many children with congenital malformation of inner ear have undergone cochlear implant (CI) surgery. The results for cochlear implant surgery in these children are very encouraging and provide a ray of hope for these patients. Objective: The main objective of this presentation is to prove that even in Mondini’s deformity Minimal incision cochlear implantation improves cosmesis, reduces post-operative infection and earliest switch on of device. Methods: We report a case of two-year-old child suffering from Mondini’s deformity who underwent CI with minimal incision cochlear implantation (MICI). MICI has been developed with the aims of reducing the impact of surgery on the patient without any preoperative shaving of hairs. Results: Patient after surgery with MICI showed better looking postauricular scar, low post-operative morbidity in comparison to conventional wider access approach and hence earliest switch on of device (1st post operative day). Conclusion: We are of opinion that MICI is safe and successful in Mondini’s deformity.

Keywords: CI, Cochlear Implant, MICI, Minimal Incision Cochlear Implantation, HL, Hearing Loss, HRCT, High Resolution Computer Tomography, MRI, Magnetic resonance imaging, SCI, Standard cochlear implantation

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2520 The Impact of Perspective Taking and Gender Differences on the Encouragement of Social Competence for the Next Generation: The Evidence From Chinese Parents

Authors: Yi Huang

Abstract:

Background: For the development of children, it is important for parents to encourage children not only on academic competence but also on children’s social competence. In the western cultural context, parents emphasize more heavily on female children’s social-behavioral development. However, whether the conclusion is correct in eastern culture and whether the parent’s gender affects such an emphasis remains unclear. And, more valuably, from the perspective of intervention, except for the nature factors - child’s gender and parent’s gender, it is also worth to probe whether the improvable factors, such as parent’s perspective taking, influence parent’s emphasis on child’s social competence. Aim: This study was aimed to investigate the impact of parent’s gender, child’s gender, and parent’s perspective-taking on parent’s attitudes of encouragement of the child’s social competence under the Chinese cultural context. Method: 461 Chinese parents whose children were in the first year of middle school during the research time participated in this study. Among all participants, there were 155 fathers and 306 mothers. The research adopted the self-report of perspective-taking, which is the sub-scale of the Interpersonal Reactivity Index and the self-report of the encouragement on a child’s social communication, which is the sub-scale of the Chinese version of The Children Rearing Practice Report. In this study, 291 parents reported regarding male children, and 170 parents reported regarding female children. Results: Contrary to the traditional western theory, which usually suggests parent puts more attention on social development and competence to girl the instead of the boy, in the Chinese context, parent emphasizes social competence more on the male child. Analogically, in China, compared to mother, father underscores the child’s social competence more heavily. By constructing the hierarchical regression model, the result indicated that after controlling the variables of the gender of child and the gender of parent, parent’s perspective-taking still explains for the variance of parent’s encouragement on child’s social competence, which means, parent’s perspective-taking predicts parent’s encouragement on child’s social competence after excluding the impact of the gender of parent and child. Conclusion: For Chinese parents, the ability of perspective-taking is beneficial to enhance their awareness of encouraging children’s social competence.

Keywords: parent; child, gender differences, perspective-taking, social development

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2519 The Role of Cyfra 21-1 in Diagnosing Non Small Cell Lung Cancer (NSCLC)

Authors: H. J. T. Kevin Mozes, Dyah Purnamasari

Abstract:

Background: Lung cancer accounted for the fourth most common cancer in Indonesia. 85% of all lung cancer cases are the Non-Small Cell Lung Cancer (NSCLC). The indistinct signs and symptoms of NSCLC sometimes lead to misdiagnosis. The gold standard assessment for the diagnosis of NSCLC is the histopathological biopsy, which is invasive. Cyfra 21-1 is a tumor marker, which can be found in the intermediate protein structure in the epitel. The accuracy of Cyfra 21-1 in diagnosing NSCLC is not yet known, so this report is made to seek the answer for the question above. Methods: Literature searching is done using online databases. Proquest and Pubmed are online databases being used in this report. Then, literature selection is done by excluding and including based on inclusion criterias and exclusion criterias. The selected literature is then being appraised using the criteria of validity, importance, and validity. Results: From six journals appraised, five of them are valid. Sensitivity value acquired from all five literature is ranging from 50-84.5 %, meanwhile the specificity is 87.8 %-94.4 %. Likelihood the ratio of all appraised literature is ranging from 5.09 -10.54, which categorized to Intermediate High. Conclusion: Serum Cyfra 21-1 is a sensitive and very specific tumor marker for diagnosis of non-small cell lung cancer (NSCLC).

Keywords: cyfra 21-1, diagnosis, nonsmall cell lung cancer, NSCLC, tumor marker

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2518 High Purity Germanium Detector Characterization by Means of Monte Carlo Simulation through Application of Geant4 Toolkit

Authors: Milos Travar, Jovana Nikolov, Andrej Vranicar, Natasa Todorovic

Abstract:

Over the years, High Purity Germanium (HPGe) detectors proved to be an excellent practical tool and, as such, have established their today's wide use in low background γ-spectrometry. One of the advantages of gamma-ray spectrometry is its easy sample preparation as chemical processing and separation of the studied subject are not required. Thus, with a single measurement, one can simultaneously perform both qualitative and quantitative analysis. One of the most prominent features of HPGe detectors, besides their excellent efficiency, is their superior resolution. This feature virtually allows a researcher to perform a thorough analysis by discriminating photons of similar energies in the studied spectra where otherwise they would superimpose within a single-energy peak and, as such, could potentially scathe analysis and produce wrongly assessed results. Naturally, this feature is of great importance when the identification of radionuclides, as well as their activity concentrations, is being practiced where high precision comes as a necessity. In measurements of this nature, in order to be able to reproduce good and trustworthy results, one has to have initially performed an adequate full-energy peak (FEP) efficiency calibration of the used equipment. However, experimental determination of the response, i.e., efficiency curves for a given detector-sample configuration and its geometry, is not always easy and requires a certain set of reference calibration sources in order to account for and cover broader energy ranges of interest. With the goal of overcoming these difficulties, a lot of researches turned towards the application of different software toolkits that implement the Monte Carlo method (e.g., MCNP, FLUKA, PENELOPE, Geant4, etc.), as it has proven time and time again to be a very powerful tool. In the process of creating a reliable model, one has to have well-established and described specifications of the detector. Unfortunately, the documentation that manufacturers provide alongside the equipment is rarely sufficient enough for this purpose. Furthermore, certain parameters tend to evolve and change over time, especially with older equipment. Deterioration of these parameters consequently decreases the active volume of the crystal and can thus affect the efficiencies by a large margin if they are not properly taken into account. In this study, the optimisation method of two HPGe detectors through the implementation of the Geant4 toolkit developed by CERN is described, with the goal of further improving simulation accuracy in calculations of FEP efficiencies by investigating the influence of certain detector variables (e.g., crystal-to-window distance, dead layer thicknesses, inner crystal’s void dimensions, etc.). Detectors on which the optimisation procedures were carried out were a standard traditional co-axial extended range detector (XtRa HPGe, CANBERRA) and a broad energy range planar detector (BEGe, CANBERRA). Optimised models were verified through comparison with experimentally obtained data from measurements of a set of point-like radioactive sources. Acquired results of both detectors displayed good agreement with experimental data that falls under an average statistical uncertainty of ∼ 4.6% for XtRa and ∼ 1.8% for BEGe detector within the energy range of 59.4−1836.1 [keV] and 59.4−1212.9 [keV], respectively.

Keywords: HPGe detector, γ spectrometry, efficiency, Geant4 simulation, Monte Carlo method

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2517 Luminescent Enhancement with Morphology Controlled Gd2O3:Eu Phosphors

Authors: Ruby Priya, Om Parkash Pandey

Abstract:

Eu doped Gd₂O₃ phosphors are synthesized via co-precipitation method using ammonia as a precipitating agent. The concentration of the Eu was set as 4 mol% for all the samples. The effect of the surfactants (CTAB, PEG, and SDS) on the structural, morphological and luminescent properties has been studied in details. The as-synthesized phosphors were characterized by X-ray diffraction technique, Field emission scanning electron microscopy, Fourier transformed infrared spectroscopy and photoluminescence technique. It was observed that the surfactants have not changed the crystal structure, but influenced the morphology of as-synthesized phosphors to a great extent. The as-synthesized phosphors are expected to be promising candidates for optoelectronic devices, biosensors, MRI contrast agents and various biomedical applications.

Keywords: co-precipitation, Europium, photoluminescence, surfactants

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2516 Oxidovanadium(IV) and Dioxidovanadium(V) Complexes: Efficient Catalyst for Peroxidase Mimetic Activity and Oxidation

Authors: Mannar R. Maurya, Bithika Sarkar, Fernando Avecilla

Abstract:

Peroxidase activity is possibly successfully used for different industrial processes in medicine, chemical industry, food processing and agriculture. However, they bear some intrinsic drawback associated with denaturation by proteases, their special storage requisite and cost factor also. Now a day’s artificial enzyme mimics are becoming a research interest because of their significant applications over conventional organic enzymes for ease of their preparation, low price and good stability in activity and overcome the drawbacks of natural enzymes e.g serine proteases. At present, a large number of artificial enzymes have been synthesized by assimilating a catalytic center into a variety of schiff base complexes, ligand-anchoring, supramolecular complexes, hematin, porphyrin, nanoparticles to mimic natural enzymes. Although in recent years a several number of vanadium complexes have been reported by a continuing increase in interest in bioinorganic chemistry. To our best of knowledge, the investigation of artificial enzyme mimics of vanadium complexes is very less explored. Recently, our group has reported synthetic vanadium schiff base complexes capable of mimicking peroxidases. Herein, we have synthesized monoidovanadium(IV) and dioxidovanadium(V) complexes of pyrazoleone derivateis ( extensively studied on account of their broad range of pharmacological appication). All these complexes are characterized by various spectroscopic techniques like FT-IR, UV-Visible, NMR (1H, 13C and 51V), Elemental analysis, thermal studies and single crystal analysis. The peroxidase mimic activity has been studied towards oxidation of pyrogallol to purpurogallin with hydrogen peroxide at pH 7 followed by measuring kinetic parameters. The Michaelis-Menten behavior shows an excellent catalytic activity over its natural counterparts, e.g. V-HPO and HRP. The obtained kinetic parameters (Vmax, Kcat) were also compared with peroxidase and haloperoxidase enzymes making it a promising mimic of peroxidase catalyst. Also, the catalytic activity has been studied towards the oxidation of 1-phenylethanol in presence of H2O2 as an oxidant. Various parameters such as amount of catalyst and oxidant, reaction time, reaction temperature and solvent have been taken into consideration to get maximum oxidative products of 1-phenylethanol.

Keywords: oxovanadium(IV)/dioxidovanadium(V) complexes, NMR spectroscopy, Crystal structure, peroxidase mimic activity towards oxidation of pyrogallol, Oxidation of 1-phenylethanol

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2515 The Response of Adaptive Mechanism of Fluorescent Proteins from Coral Species and Target Cell Properties on Signalling Capacity as Biosensor

Authors: Elif Tugce Aksun Tumerkan

Abstract:

Fluorescent proteins (FPs) have become very popular since green fluorescent protein discovered from crystal jellyfish. It is known that Anthozoa species have a wide range of chromophore organisms, and the initial crystal structure for non-fluorescent chromophores obtained from the reef-building coral has been determined. There are also differently coloured pigments in non-bioluminescent Anthozoa zooxanthellate and azooxanthellate which are frequently members of the GFP-like protein family. The development of fluorescent proteins (FPs) and their applications is an outstanding example of basic science leading to practical biotechnological and medical applications. Fluorescent proteins have several applications in science and are used as important indicators in molecular biology and cell-based research. With rising interest in cell biology, FPs have used as biosensor indicators and probes in pharmacology and cell biology. Using fluorescent proteins in genetically encoded metabolite sensors has many advantages than chemical probes for metabolites such as easily introduced into any cell or organism in any sub-cellular localization and giving chance to fixing to fluoresce of different colours or characteristics. There are different factors effects to signalling mechanism when they used as a biosensor. While there are wide ranges of research have been done on the significance and applications of fluorescent proteins, the cell signalling response of FPs and target cell are less well understood. In this study, it was aimed to clarify the response of adaptive mechanisms of coral species such as pH, temperature and symbiotic relationship and target cells properties on the signalling capacity. Corals are a rich natural source of fluorescent proteins that change with environmental conditions such as light, heat stress and injury. Adaptation mechanism of coral species to these types of environmental variations is important factor due to FPs properties have affected by this mechanism. Since fluorescent proteins obtained from nature, their own ecological property like the symbiotic relationship is observed very commonly in coral species and living conditions have the impact on FPs efficiency. Target cell properties also have an effect on signalling and visualization. The dynamicity of detector that used for reading fluorescence and the level of background fluorescence are key parameters for the quality of the fluorescent signal. Among the factors, it can be concluded that coral species adaptive characteristics have the strongest effect on FPs signalling capacity.

Keywords: biosensor, cell biology, environmental conditions, fluorescent protein, sea anemone

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2514 Electron Density Discrepancy Analysis of Energy Metabolism Coenzymes

Authors: Alan Luo, Hunter N. B. Moseley

Abstract:

Many macromolecular structure entries in the Protein Data Bank (PDB) have a range of regional (localized) quality issues, be it derived from x-ray crystallography, Nuclear Magnetic Resonance (NMR) spectroscopy, or other experimental approaches. However, most PDB entries are judged by global quality metrics like R-factor, R-free, and resolution for x-ray crystallography or backbone phi-psi distribution statistics and average restraint violations for NMR. Regional quality is often ignored when PDB entries are re-used for a variety of structurally based analyses. The binding of ligands, especially ligands involved in energy metabolism, is of particular interest in many structurally focused protein studies. Using a regional quality metric that provides chemically interpretable information from electron density maps, a significant number of outliers in regional structural quality was detected across x-ray crystallographic PDB entries for proteins bound to biochemically critical ligands. In this study, a series of analyses was performed to evaluate both specific and general potential factors that could promote these outliers. In particular, these potential factors were the minimum distance to a metal ion, the minimum distance to a crystal contact, and the isotropic atomic b-factor. To evaluate these potential factors, Fisher’s exact tests were performed, using regional quality criteria of outlier (top 1%, 2.5%, 5%, or 10%) versus non-outlier compared to a potential factor metric above versus below a certain outlier cutoff. The results revealed a consistent general effect from region-specific normalized b-factors but no specific effect from metal ion contact distances and only a very weak effect from crystal contact distance as compared to the b-factor results. These findings indicate that no single specific potential factor explains a majority of the outlier ligand-bound regions, implying that human error is likely as important as these other factors. Thus, all factors, including human error, should be considered when regions of low structural quality are detected. Also, the downstream re-use of protein structures for studying ligand-bound conformations should screen the regional quality of the binding sites. Doing so prevents misinterpretation due to the presence of structural uncertainty or flaws in regions of interest.

Keywords: biomacromolecular structure, coenzyme, electron density discrepancy analysis, x-ray crystallography

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2513 Green-Synthesized β-Cyclodextrin Membranes for Humidity Sensors

Authors: Zeineb Baatout, Safa Teka, Nejmeddine Jaballah, Nawfel Sakly, Xiaonan Sun, Mustapha Majdoub

Abstract:

Currently, the economic interests linked to the development of bio-based materials make biomass one of the most interesting areas for science development. We are interested in the β-cyclodextrin (β-CD), one of the popular bio-sourced macromolecule, produced from the starch via enzymatic conversion. It is a cyclic oligosaccharide formed by the association of seven glucose units. It presents a rigid conical and amphiphilic structure with hydrophilic exterior, allowing it to be water-soluble. It has also a hydrophobic interior enabling the formation of inclusion complexes, which support its application for the elaboration of electrochemical and optical sensors. Nevertheless, the solubility of β-CD in water makes its use as sensitive layer limit and difficult due to their instability in aqueous media. To overcome this limitation, we chose to precede by modification of the hydroxyl groups to obtain hydrophobic derivatives which lead to water-stable sensing layers. Hence, a series of benzylated β-CDs were synthesized in basic aqueous media in one pot. This work reports the synthesis of a new family of substituted amphiphilic β-CDs using a green methodology. The obtained β-CDs showed different degree of substitution (DS) between 0.85 and 2.03. These organic macromolecular materials were soluble in common organic volatile solvents, and their structures were investigated by NMR, FT-IR and MALDI-TOF spectroscopies. Thermal analysis showed a correlation between the thermal properties of these derivatives and the benzylation degree. The surface properties of the thin films based on the benzylated β-CDs were characterized by contact angle measurements and atomic force microscopy (AFM). These organic materials were investigated as sensitive layers, deposited on quartz crystal microbalance (QCM) gravimetric transducer, for humidity sensor at room temperature. The results showed that the performances of the prepared sensors are greatly influenced by the benzylation degree of β-CD. The partially modified β-CD (DS=1) shows linear response with best sensitivity, good reproducibility, low hysteresis, fast response time (15s) and recovery time (17s) at higher relative humidity levels (RH) between 11% and 98% in room temperature.

Keywords: β-cyclodextrin, green synthesis, humidity sensor, quartz crystal microbalance

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2512 Efficient Hydrosilylation of Functionalized Alkenes via Heterogeneous Zinc Oxide Nanoparticle Catalysis

Authors: Ahlam Chennani, Nadia Anter, Abdelouahed Médaghri Alaoui, Abdellah Hannioui

Abstract:

Non-precious metals such as zinc, copper, iron, and nickel are promising hydrosilylation catalysts due to their abundance, affordability, and low toxicity. This study focuses on the preparation of zinc nanoparticles using a simple, scalable method. Advanced techniques such as X-ray diffraction (XRD) and transmission electron microscopy (TEM) are used to characterize these catalysts, revealing their crystal structure and morphology. ZnO nanoparticles demonstrate high efficiency and selectivity in hydrosilylation reactions, producing silylated products. These results highlight the potential of ZnO nanocatalysts for advanced chemical transformations and practical applications in various industrial fields.

Keywords: nanoparticles, hydrosilylation, catalysts, non-precious metal

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2511 Analysis of Epileptic Electroencephalogram Using Detrended Fluctuation and Recurrence Plots

Authors: Mrinalini Ranjan, Sudheesh Chethil

Abstract:

Epilepsy is a common neurological disorder characterised by the recurrence of seizures. Electroencephalogram (EEG) signals are complex biomedical signals which exhibit nonlinear and nonstationary behavior. We use two methods 1) Detrended Fluctuation Analysis (DFA) and 2) Recurrence Plots (RP) to capture this complex behavior of EEG signals. DFA considers fluctuation from local linear trends. Scale invariance of these signals is well captured in the multifractal characterisation using detrended fluctuation analysis (DFA). Analysis of long-range correlations is vital for understanding the dynamics of EEG signals. Correlation properties in the EEG signal are quantified by the calculation of a scaling exponent. We report the existence of two scaling behaviours in the epileptic EEG signals which quantify short and long-range correlations. To illustrate this, we perform DFA on extant ictal (seizure) and interictal (seizure free) datasets of different patients in different channels. We compute the short term and long scaling exponents and report a decrease in short range scaling exponent during seizure as compared to pre-seizure and a subsequent increase during post-seizure period, while the long-term scaling exponent shows an increase during seizure activity. Our calculation of long-term scaling exponent yields a value between 0.5 and 1, thus pointing to power law behaviour of long-range temporal correlations (LRTC). We perform this analysis for multiple channels and report similar behaviour. We find an increase in the long-term scaling exponent during seizure in all channels, which we attribute to an increase in persistent LRTC during seizure. The magnitude of the scaling exponent and its distribution in different channels can help in better identification of areas in brain most affected during seizure activity. The nature of epileptic seizures varies from patient-to-patient. To illustrate this, we report an increase in long-term scaling exponent for some patients which is also complemented by the recurrence plots (RP). RP is a graph that shows the time index of recurrence of a dynamical state. We perform Recurrence Quantitative analysis (RQA) and calculate RQA parameters like diagonal length, entropy, recurrence, determinism, etc. for ictal and interictal datasets. We find that the RQA parameters increase during seizure activity, indicating a transition. We observe that RQA parameters are higher during seizure period as compared to post seizure values, whereas for some patients post seizure values exceeded those during seizure. We attribute this to varying nature of seizure in different patients indicating a different route or mechanism during the transition. Our results can help in better understanding of the characterisation of epileptic EEG signals from a nonlinear analysis.

Keywords: detrended fluctuation, epilepsy, long range correlations, recurrence plots

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