Digital Commons Network^™

Modelling And Analysis Of A Holling Type Ii Stage Structured Predator-Prey System In The Presence Of Harvesting, Jacob Lyimo, Nyimvua Shaban, Eunice Mureithi, Thadei Sagamiko

Tanzania Journal of Science

The effect of harvesting and predation on a Holling type II stage-structured predator-prey system with assumption that harvesting and predation happen only to mature preys was investigated. Stability of interior point was analysed using Routh Hurwith Criterion. Numerical simulations were carried out. The results show that harvesting and predation have strong negative impacts on population dynamics of stage structured predator-prey system.

Effects Of Seasons And Zonation On Biochemical Contents Of Two Seagrass Species Along Dar Es Salaam Coast, Tanzania, Wamwi M. Mbaga, Esther F. Mvungi

Tanzania Journal of Science

Accumulation and allocation of biochemicals in plants are affected by various factors. The influence of seasons and vertical zonation on biochemical contents of seagrasses Cymodocea rotundata and Thalassia hemprichii from Mjimwema seagrass meadow along the coast of Dar es Salaam were assessed. Samples were collected in 2016 during wet/rainy (April–May) and dry (June–July) seasons. Concentrations of crude protein, soluble carbohydrates, phosphorus, lipid, and proline were determined using standard methods. Significant higher levels of phosphorus, lipid, protein and proline were observed during the dry season than in wet season (p < 0.05). Likewise, seagrass population occurring at the shore zone expressed higher levels of biochemical contents than those found at the subtidal zones. The highest concentration of protein was recorded in Thalassia hemprichii (5.8 mg/g dw)), while those of lipid and carbohydrates (27.1 and 53.1 mg/g dw, respectively) were recorded in Cymodocea rotundata. The two species studied did not vary significantly in their biochemical concentrations in both seasons. Generally it was observed that the concentrations of studied biochemicals were up-regulated during the dry season and varied depending on the locations where the seagrass grow. Thus, both season and zonation played roles in biochemical accumulation in the seagrasses understudy, however not interactively.

Climate Change Increasing Threats On Non-Conserved Mangroves Forests Of Micheweni, Zanzibar–Tanzania, Haji M. Hamad, Islam S.S. Mchenga, Mariam I. Hamisi

Tanzania Journal of Science

Overutilization of mangroves has been reported as the factor for mangrove declining across the globe. However, currently, the global climate change has been claimed to pose significant threats to the survival of mangroves. This study analysed the impacts of climatic variability (sea level rise, temperature and precipitation) to the mangroves of Micheweni (non reserve) and Ngezi-Vumawimbi (nature forest reserve). Multi-disciplinary approach was employed to collect information on community perceptions. Secondary time series data of up to 30 years for temperature, rainfall and sea level rise were collected and analysed. Inquiry results on how local communities perceived climate change showed that …

Mixed Mode Device-To-Device Communication Scheme For Congestion Reduction And Channel Usage Optimization In 5g Cellular Networks, Chiza M. Christophe, Omar F. Hamad, Libe V. Massawe, Abdi T. Abdalla

Tanzania Journal of Science

Device-to-Device (D2D) communication schemes have gained more attention in cellular networks particularly in normalization process of the upcoming 5G networks. They have been investigated in core network offloading, congestion reduction and channel usage optimization.  The two last cases are among the major constraints in current cellular networks and are the main concerns of this paper. The paper presents a mixed mode D2D communication scheme to decentralize data collection between devices and the base station in order to reduce the number of direct connections at the base station of ultra-dense cells characterized by different levels of channel utilizations or target data …

Preliminary Palynology Of The Karoo Equivalent Tanga Beds, Coastal Tanzania: Insights On Preservation, Age And Depositional Environments, Stephen Peter Magohe

Tanzania Journal of Science

The major challenge to the current understanding of the stratigraphy of the Tanga Basin is scarcity of biostratigraphy age-control data. A number of palynomorphs retrieved from core samples of the Tanga Beds and analysed for palynology are here presented. These include bisaccate pollen grains belonging to the Alisporites-Falcisporites complex, making about 55% average of the total assemblage. The rest of the assemblage comprises other palynomorphs (pollen and spores) and phytoclasts. The miospores documented from the studied samples have poor to fairly good preservation; the organic residues (non-pollen palynomorphs) are excellently preserved. Based on palynologic evidences, and the presence of fossil …

Quantitative Assessment Of Resistivity Anisotropy In Evaluation Of Laminated Shaly Sand Hydrocarbon Reservoirs–A Case Study In The Barents Sea, Norway, Ernest S. Mulaya

Tanzania Journal of Science

Resistivity anisotropy in shaly sand lamination sequences affects the hydrocarbon evaluation in multiple dimensions of petrophysical logs. Currently, vertical resistivity (Rv) and horizontal resistivity (Rh) from 3D triaxial induction measurements can be applied simultaneously to resolve these petrophysical impacts. In this paper, an extensive analysis is offered with a focus on the hydrocarbon evaluation based on advanced petrophysical logs from a well. A critical analysis is done on the three comparable cases including clean formation as a base case, shaly sand case and laminated shaly sand case towards resolving resistivity anisotropy in a typical shaly sand laminated reservoir. The analysis …

Total Electron Content Prediction Model Using The Artificial Neural Networks Over The Eastern Africa Region, Emmanuel D. Sulungu, Christian B.S. Uiso

Tanzania Journal of Science

In this paper, development of a model using NN technique for prediction of GPS TEC over the Eastern Africa region is presented. TEC data was obtained from the Africa array and IGS network of ground based dual-frequency GPS receivers from 18 stations within the East African region. It covers approximately the area from ~2.6°N to ~26.9°S in magnetic latitudes and from ~95°E to ~112oE in magnetic longitudes. The input layer of the developed model consisted of seven neurons which were selected by considering the parameters that are known to affect the TECv data. The results showed that when the number …

An Investigation Of The Potentials Of 2-[(2-Hydroxyphenyl) Methylidene] Hydrazine-1-Carbothioamide And Its Mn(Ii) And Zn(Ii) Complexes As Antimicrobial Agents, Umar Sani, Musbahu Yahaya, Dailami S. Adam

Tanzania Journal of Science

Antibiotic resistance as a result of misuse, overuse or abuse of drugs is an issue of serious concern world over. The quest for more active and robust antimicrobial agents remains a scientific challenge and requires multimillion-dollar investment in the area of drug design and development. Here in, we report the synthesis and characterisation of a tridentate thiosemicarbazone (2-[(2-hydroxyphenyl)methylidene]hydrazine-1-carbothioamide) (HL) from salicylaldehyde and thiosemicarbazide. Its complexes with Mn(II) and Zn(II) were prepared following similar technique and characterised by melting point, FT-IR, UV –visible spectrophotometry, and elemental analysis. The Mn(II) complex showed paramagnetism with a magnetic moment value of 5.80 BM while …

Synthesis Of Semiochemicals And Related Fine Chemicals From Cashew Nut Shell Liquid, Godfrey Pius, Quintino A Mgani

Tanzania Journal of Science

This paper reports on syntheses of 3-hydroxybenzaldehyde (1) and tetradecanal (2) from the same renewable starting material (cashew nut shell liquid or CNSL), thus demonstrating the potential of the agro-waste cashew nut shells (CNS) as a source of valuable fine and industrial chemicals. The strategy employed in accomplishing the synthesis started with extraction of CNSL followed by isolation of anacardic acid (4) and decarboxylation to give cardanol (5). Compound 5 was hydrogenated followed by protection of phenolic group to give 3-pentadecylphenyl acetate (7). Benzylic oxidation of compound 7 followed by reduction and dehydration resulted into formation of 3-(pentadec-1-en-1-yl)phenol (9). Ozonolysis …

Generation Of Highly Ordered 3d Vivid Monochromatic Coloured Photonic Crystal Films Using Evaporative Induced Technique, Ikhazuagbe H. Ifijen, Esther U. Ikhuoria

Tanzania Journal of Science

Structural coloured crystal films have attracted immense attention because of numerous applications like optical sensing, anti-counterfeiting and photonic fabrics.  Herein, we successfully generated highly periodic three-dimensional (3D) monochromatic structural crystal films with brown, turquoise, blue and yellow colourations from as-synthesized poly(styrene-methyl methacrylate-acrylic acid) or P(St-MMA-AA) colloidal latex via the evaporative induced self-assembly technique. The colours were controlled through the modulation of their crystal lattice by varying their microspheres diameter from 180 nm, 120 nm, and 260 nm to 150 nm. Scanning electron microscope and atomic force microscope (SEM/AFM) analyses showed that the photonic crystal particles readily assembled into an impeccable …

Past, Present, And Future Of Intellectual Property In Space: Old Answers To New Questions, Rosario Avveduto

Washington International Law Journal

This comment critically analyzes international space law in the context of intellectual property. The issues explored, current and future, are at the crossroads of the international space legal framework and U.S. intellectual property law. The first stage of the analysis includes a brief history of space law, introducing the U.N. treaties on space activities and taking a hard look at the founding principles they enshrine. An analytical overview of the International Space Station Agreement follows, introducing the present application of space law to issues of intellectual property. This overview further considers the fundamental principles of U.S. intellectual property, especially patent …

A Qualitative Study Of Older Adults' Perspectives On Initiating Exercise And Mindfulness Practice, Diana C Parra, Julie Loebach Wetherell, Alexandria Van Zandt, Ross C Brownson, Janardan Abhishek, Eric J Lenze

Open Access Publications

BACKGROUND: Mindfulness practice and exercise are ways by which older adults can improve and maintain their physical, emotional and cognitive health.

METHODS: This single-site qualitative study gathered insights of older adults' perceptions about initiating and maintaining mindfulness and exercise practices. We carried out focus groups with 41 adults aged 65-85 who had recently initiated Mindfulness Based Stress Reduction (MBSR), structured exercise, or their combination as part of participation in a clinical trial. We used a semi-structured interview to ask them open-ended questions regarding the benefits, barriers and facilitators of participating in mindfulness and/or exercise interventions. The interview also included questions …

Community-Based Responses To Negative Health Impacts Of Sexual Humanitarian Anti-Trafficking Policies And The Criminalization Of Sex Work And Migration In The Us, Heidi Hoefinger, Jennifer Musto, P.G. Macioti, Anne E. Fehrenbacher, Nicola Mai, Calum Bennachie, Calogero Giametta

Publications and Research

System-involvement resulting from anti-trafficking interventions and the criminalization of sex work and migration results in negative health impacts on sex workers, migrants, and people with trafficking experiences. Due to their stigmatized status, sex workers and people with trafficking experiences often struggle to access affordable, unbiased, and supportive health care. This paper will use thematic analysis of qualitative data from in-depth interviews and ethnographic fieldwork with 50 migrant sex workers and trafficked persons, as well as 20 key informants from legal and social services, in New York and Los Angeles. It will highlight the work of trans-specific and sex worker-led initiatives …

A Microfluidic Paper-Based Analytical Device For Early Diagnosis And Prognosis Of Acute Myocardial Infarction, Lim Wei Yin

Student Works (2020-2029)

Acute myocardial infarction (AMI), also termed as heart attack, is often clinically screened by blood test through the measurement of cardiac biomarkers (i.e., troponin (T or I), creatine kinase (CK−MB) and myoglobin) and electrocardiography (ECG) changes which are presented to the hospital. However, the early diagnosis of AMI is challenging because the detection of biomarkers such as troponin (T or I) and CK−MB are only reliable at the intermediate and later stages (> 6 hours after chest pain onset), during myocardial injury and myocardial infarction. On the other hand, myoglobin often been used as early biomarker which is detectable within …

Parenting Paused: Pathological Video Game Use And Parenting Outcomes, Laura Stockdale, Sarah M. Coyne

Faculty Publications

For most people, playing video games is a normal recreational activity, with little disruption to gamers’ emotional, social, or physical health and well-being. However, for a small percentage of gamers, video gaming can become pathological (Fam, 2018). Substantial research has examined pathological gaming in teens and young adults (Cheng, Cheung, & Wang, 2018; Choo, Gentile, Sim, Khoo, & Liau, 2010), yet pathological gaming in adults (c.f.Holgren, 2017), especially in the context of parenthood, has been relatively ignored. The current study sought to address this limitation by studying associations between pathological gaming characteristics and parenting outcomes in a sample of men …

High-Voltage Vertical Ga2O3 Power Rectifiers Operational At High Temperatures Up To 600 K, Boyan Wang, Ming Xiao, Xiaodong Yan, Hiu Yung Wong, Jiahui Ma, Kohei Sasaki, Han Wang, Yuhao Zhang

Faculty Research, Scholarly, and Creative Activity

This work presents the temperature-dependent forward conduction and reverse blocking characteristics of a high-voltage vertical Ga₂O₃ power rectifier from 300 K to 600 K. Vertical β-Ga₂O₃ Schottky barrier diodes (SBDs) were fabricated with a bevel-field-plated edge termination, where a beveled sidewall was implemented in both the mesa and the field plate oxide. The Schottky barrier height was found to increase from 1.2 eV to 1.3 eV as the temperature increases from 300 K to 600 K, indicating the existence of barrier height inhomogeneity. The net donor concentration in the drift region shows little dependence …

Childhood Disability: Challenges And Theory-Informed Child Life Interventions In The Healthcare Setting, Fatema-Zahra Jaffer

Graduate Student Independent Studies

Children with intellectual, sensory, physical, and/or speech disabilities encounter a proliferation of challenges in the healthcare environment. Such challenges are exacerbated by insufficient knowledge in doctors, nurses, child life specialists, and other healthcare providers in bias-free and specialized healthcare delivery. To remedy this, pertinent methods informed by theoretical perspectives of atypical development that ameliorate stress and augment coping in children with disabilities are warranted. Therefore, the purpose of this independent study is to provide a synthesis of the literature that chronicles this topic. Multifarious child life interventions that are premised on contemporary developmental frameworks of childhood disability will be presented. …

Quantum Mechanics And Features Of Its Training, Gulom Bazarbaevich Samatov, Rustam Ummatqulovich Elmurodov

Bulletin of Gulistan State University

The article discusses the issues of the formation of quantum mechanics, the creation of a mathematical apparatus, physical interpretation, the dialectics of new patterns and the originality of events in quantum mechanics. In quantum mechanics, the duality of micro-objects and other peculiar properties are studied. This article discusses the revival of quantum mechanics, the formation of the mathematical apparatus, their physical interpretation, the dialectics of new laws, the peculiarity of quantum-mechanical events and microparticles. At the end of the 19th century, physicists of developed countries could not explain, on the basis of the mathematical apparatus of classical physics and experimental …

Features Of Social And Individual – Biological Development Of The Person In The Educational Process, Аtanazar Karimovich Raximov, Gulyor Аtanazar Qizi Karimova

Bulletin of Gulistan State University

The article describes the interaction of many subjects despite pedagogy in the formation of personality the existence of specific stages in the mental, physical and physiological development of pupils, their role in the system of human relations and their originality and the importance of reading in the formation of spirituality, moral education and the virtues of humanity. It also describes the socio-historical environment, the specific conditions of life and upbringing, the individual, specific biological, hereditary, anatomical-physiological features of the personality, and the connection with the effectiveness of education. The existence of genetic differences between intelligence, talent and ability in humans …

Innovative Ict-Based Foreign Language Learning: Evaluation Techniques, Assisted Learning And Foreign Language Teaching, Zaynab Аbduamitovna Karimova

Bulletin of Gulistan State University

В этой статье мы рассмотрим, как ИКТ (информационно-коммуникационные технологии) могут быть использованы в оценке преподавания английского языка. За прошедший период мы выработали лучшее понимание того, как мы могли бы помочь выучить язык, и эти изменения должны быть отражены в нашей оценке. Нам нужно развивать навыки и быть «пользователями» языка. Изменилась и цель оценки: речь идет не об оценке уровня умений студентов, а о мотивации и саморефлексии. В настоящее время ИКТ (информационно-коммуникационные технологии) имеют важнейший аспект в образовании и существенную роль в овладении иностранным языком, а также значительную проблему в современном образовании во всем мире, которая будет способствовать овладению студентами и …

Transition Of Care In Paediatric Surgery: Current Practices And Perspectives Of Paediatric Surgeons In Malaysia, Shung K. Tan, Anand Sanmugam, Mahmoud Ramanujam, Tindivanam M., Mohan A. Nallusamy, Zakaria Zahari, Thambidorai R. Rao

Sultan Qaboos University Medical Journal

Objectives: Transition of care (TOC) from paediatric to adult care is still at an early stage in Malaysia. This study aimed to explore current practices and perspectives regarding TOC among paediatric surgeons in Malaysia. Methods: This study was carried out between June and December 2017. All 48 paediatric surgeons currently working in Malaysia were invited to participate in a questionnaire-based survey to assess demographic characteristics and practices and perspectives regarding TOC. Results: A total of 38 paediatric surgeons participated in the survey (response rate: 79.2%). Overall, 97.4% did not have an organised TOC model in their institution, with most (65.8%) …

For Whom The Bell Does Not Toll: The Invisible Saga Of Cancer Caregivers, Ritu Lakhtakia, Ikram Burney

Sultan Qaboos University Medical Journal

No abstract provided.

Comparison Of Nitroglycerin Versus Lignocaine Spray To Attenuate Haemodynamic Changes In Elective Surgical Patients Undergoing Direct Laryngoscopy And Endotracheal Intubation: A Prospective Randomised Study, Rohit K. Varshney, Mukesh K. Prasad, Megha

Sultan Qaboos University Medical Journal

Objectives: This study aimed to compare the effects of nitroglycerin (NTG) versus lignocaine spray in blunting the pressor response during direct laryngoscopy and endotracheal intubation. Methods: This study was conducted between January and June 2018 in the Department of Anesthesiology, Teerthankar Mahaveer Medical College, Moradabad, India. A total of 90 elective surgical patients of American Society of Anesthesiologists physical status grades I or II were divided into three groups, comprising two treatment groups and one control group. Patients in the treatment groups received either one puff (1.5 mg/kg) of lignocaine 10% spray or one puff (400 μg) of NTG spray …

Lactation Ketoacidosis: A Case Series, Abdullah M. Al Alawi, Usama Al Amri, Henrik

Sultan Qaboos University Medical Journal

Lactation ketoacidosis is an extremely rare type of high anion gap metabolic acidosis. We report two lactating women who were diagnosed with lactation ketoacidosis. The first patient presented to the Emergency Department at Royal Darwin Hospital, Darwin, Australia, in 2018 with lethargy, nausea and abdominal pain after she commenced a new diet regimen based on three meals of protein per day and free of glucose, gluten and dairy products. The second patient presented to the Emergency Department at Sultan Qaboos University Hospital, Muscat, Oman, in 2018 with headache, severe malaise, epigastric pain and worsening of gastroesophageal symptoms. Blood investigation results …

A Review Of Obstetrical Outcomes And Complications In Pregnant Women After Bariatric Surgery, Yasmeen A. Haseeb

Sultan Qaboos University Medical Journal

Bariatric surgery (BS) is a novel treatment for weight reduction with longer lasting health benefits. This review aimed to summarise the available evidence regarding the fetomaternal outcomes and the most common challenges and complications in pregnancies following BS. Google Scholar (Google LLC, Mountain View, California, USA) and PubMed^® (National Library of Medicine, Bethesda, Maryland, USA) databases were searched for articles published until December 2018. A total of 64 articles were included in this review and results showed that BS mitigates the risk of gestational diabetes mellitus, hypertensive disorders in pregnancy and fetal macrosomia. However, it can also have detrimental …

Pharmacological Approaches To Diabetic Gastroparesis: A Systematic Review Of Randomised Clinical Trials, Mohammad Z. Asha, Sundos Fh Khalil

Sultan Qaboos University Medical Journal

Pharmacological interventions of diabetic gastroparesis (DG) constitute an essential element of a patient’s management. This article aimed to systematically review the available pharmacological approaches of DG, including their efficacy and safety. A total of 24 randomised clinical trials (RCTs) that investigated the efficacy and/or safety of medications targeting DG symptoms were identified using several online databases. Their results revealed that metoclopramide was the only approved drug for accelerating gastric emptying and improving disease symptoms. However, this medication may have several adverse effects on the cardiovascular and nervous systems, which might be resolved with a new intranasal preparation. Acceptable alternatives are …

A Case Of Intertriginous And Flexural Exanthema Caused By Amoxicillin, Bárbara Cancela-Díez, David López-Delgado, José Ruiz-Villaverde, Ricardo

Sultan Qaboos University Medical Journal

We report a 50-year-old male patient who presented to the Dermatological Outpatient Clinic at the Hospital Universitario San Cecilio, Granada, Spain, in 2017 with symmetrical inguinal eruption and eruption on the dorsum of both feet four hours after the intake of amoxicillin. Physical examination showed confluent non-palpable purpuric macules covering the dorsum of both feet and medial malleolus, giving rise to dusky erythema in some areas. Only oral antihistamines were prescribed and cutaneous exanthema resolved within three weeks. Symmetric drug-related intertriginous and flexural exanthema (SDRIFE) is a sub-type of systemic allergic contact dermatitis, where previous sensitisation can only be demonstrated …

Twitter Use By Academic Libraries In New York State, Sheena Philogene

Urban Library Journal

Twitter can be a productive tool for academic libraries to use when sharing information, marketing services, and building relationships with students, yet it is difficult to know whether academic libraries are utilizing this platform by creating an independent library account. Furthermore, if academic libraries do have accounts, it is valuable to understand what academic libraries use Twitter for, and what kinds of media they share. The purpose of this study then is to investigate whether academic libraries in New York State (NYS) use Twitter, and if they do, how and why. Based on a sample of 226 academic libraries of …

Secondary Poisoning And Ecological Effects Of Anticoagulant Rodenticides, Elizabeth Kovacs

D.U.Quark

No abstract provided.

Storm On The Horizon: Climate Change, Hurricanes, And The Future Of The Eastern Caribbean, Joseph P. Odegaard

Student Theses 2015-Present

Hurricanes are a fact of life in the Caribbean. This meteorological reality has shaped the islands’ development throughout its history. However, in recent years, the Atlantic’s most fearsome storms have been unprecedented, both in strength and number. This paper explores the relationship between climate change and hurricanes and the effect this relationship has on the Eastern Caribbean. Chapter 1 uses quantitative data from a variety of sources, including the Intergovernmental Panel on Climate Change and the Millennium Ecosystem Assessment of the United Nations, as well as the National Oceanic and Atmospheric Association and the National Climate Assessment of the United …