CLIMATE CHANGE AND ENVIRONMENTAL DEGRADATION: A SERIOUS THREAT TO GLOBAL SECURITY

Climate change and environmental degradation are significant threats to the survival of humanity. However, existing research focuses on the nexus between climate change and environmental degradation, highlighting the causes that strengthen the relationship. Despite experts expressing strong sentiments about the two phenomena being risks to global security, the assertions have drawn inadequate attention from scholars and practitioners, who prioritize illustrating the causes and impacts of climate change and environmental degradation instead. This narrative review aims to fill the gap by presenting evidence that affirms the theory about climate change and environmental degradation being primary security concerns for contemporary society. Climate change and environmental degradation cause security concerns through threats to military infrastructure and installations, depletion of resources leading to conflicts over disputed claims, and displacement of people, causing migration and refugees. Therefore, mitigating the causes of climate change is the most plausible strategy for reducing the threat to national and global security.  Article visualizations

Gene duplication in bovine brain myelin proteolipid and homology with related proteins

AbstractAnalysis of the amino acid sequence of bovine brain myelin proteolipid reveals not only extensive internal homology, but also homology with portions of the myelin basic protein, the peripheral nerve myelin protein, Po, and with the small proteolipid subunit of mitochondrial ATP synthase. These results suggest that the myelin proteolipid gene has been constructed from a small number of genetic elements, and that these elements are also found in non-myelin proteins. Furthermore, the proteolipid appears to have evolved by acquisition of elements from a ‘gene pool’ over a period of time, rather than by a simple duplication mechanism

A Game Based Innovative teaching and learning environment to enhance progression and performance of students

Activity-based and game-based learning environment significantly enhances the learning experience and stimulates interest and increases the attention span and concentration of learners. Game-based or activity-based learning becomes essential to achieve the learning objectives and overall comprehension of students of a particular concept. Several game-based classroom activities have been proposed in the past and implemented with quite a success rate. This research study proposes a game-based activity that is intended not only for enhancing attention span or generating interest in learning in students however it addresses several issues and takes into consideration (1) the importance of revision of topics and (2) the importance of identifying topics that students have not been able to fully or partially comprehend (3) feedback on the topics delivered (4) ensuring individual progress of students (5) enhances attention span of students (6) stimulates competitive environment, (7) enhances intrinsic motivation amongst students, and (8) enhances comprehension of concepts & progression of students

Production, optimization, and physicochemical characterization of biodiesel from seed oil of indigenously grown Jatropha curcas

With the growing demand for vegetable oils, alternative non-edible feedstocks like Jatropha curcas seed oil have gained interest for biodiesel production. The study aimed to comprehensively evaluate the physicochemical properties and biodiesel production potential of locally produced J. curcas seeds in Pakistan. Two different approaches were applied: a chemical synthesis approach involving acidic pretreatment and alkaline transesterification, and a biosynthetic approach using a lipase-producing strain of the Bacillus subtilis Q5 strain. The microbial biosynthesized biodiesel was further optimized using the Plackett–Burman design. The physicochemical properties of the J. curcas methyl esters were analyzed to assess their suitability as biodiesel fuel. Initially, the raw oil had a high free fatty acid content of 13.11%, which was significantly reduced to 1.2% using sulfuric acid pretreatment, keeping the oil to methanol molar ratio to be 1:12. Afterward, alkaline transesterification of purified acid-pretreated seed oil resulted in 96% biodiesel yield at an oil to methanol molar ratio of 1:6, agitation of 600 revolutions per minute (RPM), temperature 60°C, and time 2 h. Moreover, alkaline transesterification yielded ∼98% biodiesel at the following optimized conditions: oil to methanol molar ratio 1:6, KOH 1%, time 90 min, and temperature 60°C. Similarly, the Bacillus subtilis Q5 strain yielded ∼98% biodiesel at the following optimized conditions: oil: methanol ratio of 1:9, agitation 150 RPM, inoculum size 10%, temperature 37°C, and n-hexane 10%. The fuel properties of J. curcas seed biodiesel are closely related to standard values specified by the American Society for Testing and Materials (ASTM D6751–20a), indicating its potential as a viable biodiesel fuel source

MS

thesisThis thesis investigates the feasibility of constructing a structural wall for a residential housing structure from layers of plastic foam. The wall will be used in a new process, now under development for rapid prototyping of residential housing structures (RPRH). Use of this foam wall in RPRH will allow for rapid production of custom designed temporary housing for events such as the Olympics or in response to emergencies such as hurricanes or other large-scale refugee evacuations. Custom homes can be rapidly and inexpensively designed that include unusual, exotic features such as bas-relief sculptures on the external walls, fireplaces or aquariums built into the structure or walls with complex curvature. Previous research has shown that home construction using wood as the primary structural element works well but it usually takes 2 to 6 months to build. The onsite construction requires crews of skilled tradesman and is typically limited to rectangular designs. Of the overall cost, 20-25% is directly tied to manual labor. This thesis reports on an alternative technique, which will build a house in 2-3 days, requires only a 2-3 person crew and can be built directly from the files generated with Computer Aided Design (CAD). To achieve this goal, a structural element for this alternative technique is needed. It is the aim of this thesis to design, construct and test a structural wall for residential building structures using polystyrene foam as the primary structural element

Inherently boosted switched inductor hybrid converter with AC and DC outputs for DC nanogrid applications

This paper presents a novel hybrid converter which is capable of carrying AC and DC loads simultaneously at different ports. The converter is designed by using a full bridge inverter at the nodes between the active switched inductor based high gain DC-DC converter. After inserting impedance into the current path, the inherent protection against the shoot through that often happens with a voltage source converter (VSI) is established. In addition, the modulation is such that the converter does not have to rely on shoot through to work, like most hybrid converters do. Instead, an extra charging mode has been added. This not only increases the voltage gain but also provides a flexible control with two duty ratios. The steady state operation of the converter is analyzed in five modes and their voltage relations are found out. A suitable pulse width modulation is realized to generate the different modes of operations. A prototype of the proposed converter is developed in the laboratory which is tested for suitable duty ratios operating for a maximum power of 600 W when the input voltage is maintained at 32 V. The converter finds its suitability in the nanogrid/microgrid where different loads are to be supplied from a single source

A Game Based Innovative teaching and learning environment to enhance progression and performance of students

Activity-based and game-based learning environment significantly enhances the learning experience and stimulates interest and increases the attention span and concentration of learners. Game-based or activity-based learning becomes essential to achieve the learning objectives and overall comprehension of students of a particular concept. Several game-based classroom activities have been proposed in the past and implemented with quite a success rate. This research study proposes a game-based activity that is intended not only for enhancing attention span or generating interest in learning in students however it addresses several issues and takes into consideration (1) the importance of revision of topics and (2) the importance of identifying topics that students have not been able to fully or partially comprehend (3) feedback on the topics delivered (4) ensuring individual progress of students (5) enhances attention span of students (6) stimulates competitive environment, (7) enhances intrinsic motivation amongst students, and (8) enhances comprehension of concepts & progression of students

Novel Scalable Topologies of High Power Density Quadratic Converters With Low Voltage Stress on Power Diode

High-gain dc–dc converters are used for a number of applications including the power processing of several low-voltage renewable energy sources (solar photovoltaic and fuel cells) while they are integrated into a microgrid. This article introduces two novel designs of high power density nonisolated quadratic boost converters, which neither uphold the cascaded architecture nor involve coupled inductors in them. The proposed converters utilize the switched-inductors and switched-capacitor-based modules for voltage boosting. Despite having a higher output voltage, the proposed topology in its extended mode offloads the issue of high voltage stress at the devices. The output voltage can be extended to further higher levels without requiring additional circuits for peak inverse voltage (PIV) suppression at the output diode. The current at the input and output terminals are continuous, which facilitates the converter for various applications such as distributed generation (DG)s integration to microgrid and uninterruptible power supplies for integrated battery storage systems. The switched-inductor-switched-capacitor quadratic converter and its extended topology, extended switched-inductor-switched-capacitor quadratic converter, are analyzed thoroughly in different modes of conduction and the performance is justified by developing a hardware prototype ranging for a maximum power of 400 W. The switching frequency is maintained at 50 kHz

Age and frailty are independently associated with increased COVID-19 mortality and increased care needs in survivors: results of an international multi-centre study

Introduction: Increased mortality has been demonstrated in older adults with coronavirus disease 2019 (COVID-19), but the effect of frailty has been unclear. Methods: This multi-centre cohort study involved patients aged 18 years and older hospitalised with COVID-19, using routinely collected data. We used Cox regression analysis to assess the impact of age, frailty and delirium on the risk of inpatient mortality, adjusting for sex, illness severity, inflammation and co-morbidities. We used ordinal logistic regression analysis to assess the impact of age, Clinical Frailty Scale (CFS) and delirium on risk of increased care requirements on discharge, adjusting for the same variables. Results: Data from 5,711 patients from 55 hospitals in 12 countries were included (median age 74, interquartile range [IQR] 54–83; 55.2% male). The risk of death increased independently with increasing age (>80 versus 18–49: hazard ratio [HR] 3.57, confidence interval [CI] 2.54–5.02), frailty (CFS 8 versus 1–3: HR 3.03, CI 2.29–4.00) inflammation, renal disease, cardiovascular disease and cancer, but not delirium. Age, frailty (CFS 7 versus 1–3: odds ratio 7.00, CI 5.27–9.32), delirium, dementia and mental health diagnoses were all associated with increased risk of higher care needs on discharge. The likelihood of adverse outcomes increased across all grades of CFS from 4 to 9. Conclusion: Age and frailty are independently associated with adverse outcomes in COVID-19. Risk of increased care needs was also increased in survivors of COVID-19 with frailty or older age.</p

Delayed colorectal cancer care during covid-19 pandemic (decor-19). Global perspective from an international survey

Background The widespread nature of coronavirus disease 2019 (COVID-19) has been unprecedented. We sought to analyze its global impact with a survey on colorectal cancer (CRC) care during the pandemic. Methods The impact of COVID-19 on preoperative assessment, elective surgery, and postoperative management of CRC patients was explored by a 35-item survey, which was distributed worldwide to members of surgical societies with an interest in CRC care. Respondents were divided into two comparator groups: 1) ‘delay’ group: CRC care affected by the pandemic; 2) ‘no delay’ group: unaltered CRC practice. Results A total of 1,051 respondents from 84 countries completed the survey. No substantial differences in demographics were found between the ‘delay’ (745, 70.9%) and ‘no delay’ (306, 29.1%) groups. Suspension of multidisciplinary team meetings, staff members quarantined or relocated to COVID-19 units, units fully dedicated to COVID-19 care, personal protective equipment not readily available were factors significantly associated to delays in endoscopy, radiology, surgery, histopathology and prolonged chemoradiation therapy-to-surgery intervals. In the ‘delay’ group, 48.9% of respondents reported a change in the initial surgical plan and 26.3% reported a shift from elective to urgent operations. Recovery of CRC care was associated with the status of the outbreak. Practicing in COVID-free units, no change in operative slots and staff members not relocated to COVID-19 units were statistically associated with unaltered CRC care in the ‘no delay’ group, while the geographical distribution was not. Conclusions Global changes in diagnostic and therapeutic CRC practices were evident. Changes were associated with differences in health-care delivery systems, hospital’s preparedness, resources availability, and local COVID-19 prevalence rather than geographical factors. Strategic planning is required to optimize CRC care