Resiliency in Deep Convolutional Neural Networks

The enormous success and popularity of deep convolutional neural networks for object detection has prompted their deployment in various real-world applications. However, their performance in the presence of hardware faults or damage that could occur in the field has not been studied. This thesis explores the resiliency of six popular network architectures for image classification, AlexNet, VGG16, ResNet, GoogleNet, SqueezeNet and YOLO9000, when subjected to various degrees of failures. We introduce failures in a deep network by dropping a percentage of weights at each layer. We then assess the effects of these failures on classification performance. We find the fitness of the weights and then dropped from least fit to most fit weights. Finally, we determine the ability of the network to self-heal and recover its performance by retraining its healthy portions after partial damage. We try different methods to re-train the healthy portion by varying the optimizer. We also try to find the time and resources required for re-training. We also reduce the number of parameters in GoogleNet, VGG16 to the size of SqueezeNet and re-trained with varying percentage of dataset. This can be used as a network pruning method

Synthesis of 7-dehydrocholesterol through hexacarbonyl molybdenum catalyzed elimination reaction

The efficiency of hexacarbonyl molybdenum catalyzed elimination reaction of the allylic acetates has been improved by the presence of O,N-bis(trimethylsilyl) acetamide in the reaction medium. The methodology is particularly well employed for the elimination of 7-acetoxycholesterol-3-acetate(cholestrol-3,7-diacetate) for which the resulting product obtained was exclusively 5,7-homoannular diene(7-dehydrocholesterol-3-acetate). Good yield is achieved (up to 70 %) while decreasing the side products formation and reducing the costs as compared to the previously used procedures. Hexacarbonyl molybdenum elimination reaction is greatly influenced by the reaction temperature, at low as well as at high temperature low yield of the homoannular diene product is separated while at moderate conditions of temperature high products formation is observed. KEY WORDS: Hexacarbonyl molybdenum, Elimination, Deacetoxylation, 7-Dehydrocholesterol, BSA Bull. Chem. Soc. Ethiop. 2011, 25(2), 247-254

The Relationship between Cash Flow Volatility and Dividend Payout Ratio: Evidence from Pakistan’s Non-Financial Firms

The current study scrutinizes the impact of cash flow volatility on the behaviour of firms regarding dividend payout. It intends to explain how dividend payment is a good source of attraction for investors. A panel data set of 274 non-financial firms of Pakistan was used for analysis covering the period 2006-2018. The estimates of the Generalized Method of Moments (GMM) revealed that volatility in the cash flow of firms adversely affects their dividend payout behavior. It implies that variations in cash flow cause cash shortfall and accordingly, firms resort to cutting their dividend payment. The empirical findings of this study suggest that firms should sustain their financial health by accumulating cash in profitable times. Moreover, the managers should consider cash flow volatility in their risk management decisions

PREVALENCE OF DENGUE VIRAL INFECTION IN PESHAWAR, KPK, PAKISTAN

Background: Dengue is a widespread mosquito-borne viral infection in human beings, which is a major public health concern all over the world. In recent years, dengue is predominant in the tropics and subtropics with a high incidence and increased considerably over the last three decades. Objective: To investigate the prevalence of dengue in Peshawar, Khyber Pakhunkhwa, Province of Pakistan. A total of 823 samples were collected from 823 patients by puncturing the vein in aseptic condition. Serum of patient was analyzed by Immunochromatography technique (ICT). Results: Out of patients, 671 were male and 152 were female. Among the total of 823 samples, 196 (23.81%) patients were positive for Dengue Non-Structure 1 (NS1) while 627 (76.18%) were negative. In male patients 147 (21.90%) were positive for Dengue NS1 while 524 (78.09%) were negative. Out of 152 (18.46%) female patients 49 (32.23%) were positive for Dengue NS1 and remaining 103 (67.76%) were negative. Conclusion: It is concluded that the prevalence of dengue infection is higher in male than in female due to susceptibility of male to certain risk of dengue. Key Words: Prevalence, Dengue viral infection, Peshawa

Gabapentin and its salicylaldehyde derivative alleviate allodynia and hypoalgesia in a cisplatin-induced neuropathic pain model

Cisplatin is an effective chemotherapeutic agent indicated in cancer chemotherapy. However, its clinical use is associated with peripheral neuropathy that invariably impairs patient quality of life. Gabapentin (GBP) is an effective analgesic for neuropathic pain conditions but its clinical efficacy in cisplatin-induced neuropathic pain (CINP) is limited, in addition to generating unwanted side-effects. In this study, a gabapentin-salicylaldehyde derivative [gabapentsal (GPS)] was synthesized and evaluated to explore any potential benefit in comparison with GBP in a rat model of CIPN. Administration of cisplatin (3.0 mg/kg/week, i.p.) for five consecutive weeks generated reproducible mechanical-allodynia (decreased paw withdrawal threshold to von Frey filament application; PWT, g) and thermal hypoalgesia (increased nociceptive reaction latency in the hot plate paradigm; s). Treatment with GBP or its derivative on the 37th day of the experimental protocol, dose dependently attenuated cisplatin-induced nocifensive behaviors. Accordingly, doses of GBP (50-100 mg/kg, i.p.) and GPS (25-100 mg/kg, i.p.) suppressed the expression of CINP by normalizing the PWT and hot plate response latency 1 h and 3 h post administration. In the rotarod paradigm, GBP at all doses markedly impaired motor performance, whilst GPS was devoid of motor incoordination except at the highest dose, when a mild impairment occurred. Salicylaldehyde alone had no effect on CINP or rotarod performance and neither was there any synergism when coadministered with GBP. These findings suggest that both GBP and GPS have beneficial effects in the neuropathic pain model though GPS may be potentially more useful in the management of CINP

Novel hydroquinone derivatives alleviate algesia, inflammation and pyrexia in the absence of gastric ulcerogenicity

Purpose: To synthesize and characterize novel hydroquinone compounds that exhibit an aspirin-like pharmacological profile devoid of ulcerogenic side effects.Methods: Two novel hydroquinone derivatives, viz, 2,5-bis(piperidinomethyl)hydroquinone and 2,5- bis(pyrrolidinomet hyl)hydroquinone, were synthesized by refluxing hydroquinone, paraformaldehyde and secondary amines (piperidine or pyrrolidine) in ethanol. The structures were authenticated by infrared (IR) spectroscopy, elemental analysis, mass spectrometry (MS) and 1H and 13C nuclear magnetic resonance (NMR) spectroscopic techniques. The synthesized derivatives were evaluated for antinociceptive, anti-inflammatory and antipyretic activities along with gastric-ulcerogenicity using wellknown testing paradigms. Aspirin served as reference standard.Results: The newly synthesized hydroquinone derivatives, significantly attenuated tonic visceral chemically-induced nociception at 10 mg/kg (p < 0.01, p < 0.001), 20 and 40 mg/kg (p < 0.001), inhibited the temporal-inflammatory reaction at 50 mg/kg (2 - 5 h, p < 0.05, p < 0.001), 100 and 150 mg/kg (1 - 5 h, p < 0.05, p < 0.01, p < 0.001) in addition to alleviating the febrile-response at test doses during 0.5 h (p < 0.05, p < 0.01, p < 0.001), 1 and 1.5 h (p < 0.001) of the study period. The synthesized compounds exhibited improved gastric tolerability profile since they were devoid of aspirin-associated biochemical and ulcerative changes. The in silico studies predicted high binding affinity of the hydroquinone derivatives to the active site of the cyclooxygenase 2 (COX-2) enzyme.Conclusion: The synthesized hydroquinone compounds possess analgesic, antipyretic and antiinflammatory properties with low gastric-ulcerogenic potential. This may be credited to preferential inhibition of the COX-2 enzyme and the beneficial basic rather than acidic chemical nature of the compounds. However, further molecular studies are required to substantiate these findings.Keywords: 2,5-Bis(piperidinomethyl)hydroquinone], 2,5- is(pyrrolidinomethyl)hydroquinone, Antiinflammatory, Antinociceptive, Antipyretic, Gastric-ulcerogenicity, Algesi

COVID‐19 among health care workers and their impact on the health care system in a teaching hospital in Pakistan : a cross sectional observational study

Background and Aims: Health care workers (HCWs) are thought to be high‐risk population for acquiring coronavirus disease (COVID‐19). The COVID‐19 emergence has had a profound effect on healthcare system. We sought to investigate the COVID‐19 among HCWs and their effects on the healthcare system.Methods: A cross sectional observational study was conducted at Timergara teaching hospital. The study included HCWs with positive real time polymerase chain reaction (Q‐PCR) for severe acute respiratory syndrome coronavirus (SARS‐CoV‐2). The study duration was from April to September, 2020. The demographic profile of each recruited subject was collected through structured interview. The patient's admissions to hospital were collected for the 5 months before (October 2019–February 2020) and 5 months after lockdown (March–July 2020).Results: A total of 72 out of 689 (10%) HCWs were tested positive for SARS‐CoV‐2, of whom 83% were front‐liners. The majority were male (72%), with comorbidities (14%) and no mortality. The structured interview of all participants showed that the healthcare setting was the major possible source of infection (97%). The patient admissions into the hospital were reduced by 42% during lockdown than prelockdown period. The patients admission was significantly decreased in the medical ward during lockdown (60% decrease; p < 0.01) with slightly similar trends in other departments.Conclusion: In conclusion, we found increased risk of COVID‐19 for front‐line HCWs. Lack of mortality was the favorable outcome. Lack of replacing the infected HCWs possibly explained the marked decrease in hospital admissions, and potential inadequate healthcare delivery during the lockdown. Understanding SARS‐CoV‐2 among HCWs and their impact on health‐care system will be crucial for countries under COVID‐19 crises or in case of future pandemic to deliver proper health services.peer-reviewe

Global burden of 288 causes of death and life expectancy decomposition in 204 countries and territories and 811 subnational locations, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021

BACKGROUND Regular, detailed reporting on population health by underlying cause of death is fundamental for public health decision making. Cause-specific estimates of mortality and the subsequent effects on life expectancy worldwide are valuable metrics to gauge progress in reducing mortality rates. These estimates are particularly important following large-scale mortality spikes, such as the COVID-19 pandemic. When systematically analysed, mortality rates and life expectancy allow comparisons of the consequences of causes of death globally and over time, providing a nuanced understanding of the effect of these causes on global populations. METHODS The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 cause-of-death analysis estimated mortality and years of life lost (YLLs) from 288 causes of death by age-sex-location-year in 204 countries and territories and 811 subnational locations for each year from 1990 until 2021. The analysis used 56 604 data sources, including data from vital registration and verbal autopsy as well as surveys, censuses, surveillance systems, and cancer registries, among others. As with previous GBD rounds, cause-specific death rates for most causes were estimated using the Cause of Death Ensemble model-a modelling tool developed for GBD to assess the out-of-sample predictive validity of different statistical models and covariate permutations and combine those results to produce cause-specific mortality estimates-with alternative strategies adapted to model causes with insufficient data, substantial changes in reporting over the study period, or unusual epidemiology. YLLs were computed as the product of the number of deaths for each cause-age-sex-location-year and the standard life expectancy at each age. As part of the modelling process, uncertainty intervals (UIs) were generated using the 2·5th and 97·5th percentiles from a 1000-draw distribution for each metric. We decomposed life expectancy by cause of death, location, and year to show cause-specific effects on life expectancy from 1990 to 2021. We also used the coefficient of variation and the fraction of population affected by 90% of deaths to highlight concentrations of mortality. Findings are reported in counts and age-standardised rates. Methodological improvements for cause-of-death estimates in GBD 2021 include the expansion of under-5-years age group to include four new age groups, enhanced methods to account for stochastic variation of sparse data, and the inclusion of COVID-19 and other pandemic-related mortality-which includes excess mortality associated with the pandemic, excluding COVID-19, lower respiratory infections, measles, malaria, and pertussis. For this analysis, 199 new country-years of vital registration cause-of-death data, 5 country-years of surveillance data, 21 country-years of verbal autopsy data, and 94 country-years of other data types were added to those used in previous GBD rounds. FINDINGS The leading causes of age-standardised deaths globally were the same in 2019 as they were in 1990; in descending order, these were, ischaemic heart disease, stroke, chronic obstructive pulmonary disease, and lower respiratory infections. In 2021, however, COVID-19 replaced stroke as the second-leading age-standardised cause of death, with 94·0 deaths (95% UI 89·2-100·0) per 100 000 population. The COVID-19 pandemic shifted the rankings of the leading five causes, lowering stroke to the third-leading and chronic obstructive pulmonary disease to the fourth-leading position. In 2021, the highest age-standardised death rates from COVID-19 occurred in sub-Saharan Africa (271·0 deaths [250·1-290·7] per 100 000 population) and Latin America and the Caribbean (195·4 deaths [182·1-211·4] per 100 000 population). The lowest age-standardised death rates from COVID-19 were in the high-income super-region (48·1 deaths [47·4-48·8] per 100 000 population) and southeast Asia, east Asia, and Oceania (23·2 deaths [16·3-37·2] per 100 000 population). Globally, life expectancy steadily improved between 1990 and 2019 for 18 of the 22 investigated causes. Decomposition of global and regional life expectancy showed the positive effect that reductions in deaths from enteric infections, lower respiratory infections, stroke, and neonatal deaths, among others have contributed to improved survival over the study period. However, a net reduction of 1·6 years occurred in global life expectancy between 2019 and 2021, primarily due to increased death rates from COVID-19 and other pandemic-related mortality. Life expectancy was highly variable between super-regions over the study period, with southeast Asia, east Asia, and Oceania gaining 8·3 years (6·7-9·9) overall, while having the smallest reduction in life expectancy due to COVID-19 (0·4 years). The largest reduction in life expectancy due to COVID-19 occurred in Latin America and the Caribbean (3·6 years). Additionally, 53 of the 288 causes of death were highly concentrated in locations with less than 50% of the global population as of 2021, and these causes of death became progressively more concentrated since 1990, when only 44 causes showed this pattern. The concentration phenomenon is discussed heuristically with respect to enteric and lower respiratory infections, malaria, HIV/AIDS, neonatal disorders, tuberculosis, and measles. INTERPRETATION Long-standing gains in life expectancy and reductions in many of the leading causes of death have been disrupted by the COVID-19 pandemic, the adverse effects of which were spread unevenly among populations. Despite the pandemic, there has been continued progress in combatting several notable causes of death, leading to improved global life expectancy over the study period. Each of the seven GBD super-regions showed an overall improvement from 1990 and 2021, obscuring the negative effect in the years of the pandemic. Additionally, our findings regarding regional variation in causes of death driving increases in life expectancy hold clear policy utility. Analyses of shifting mortality trends reveal that several causes, once widespread globally, are now increasingly concentrated geographically. These changes in mortality concentration, alongside further investigation of changing risks, interventions, and relevant policy, present an important opportunity to deepen our understanding of mortality-reduction strategies. Examining patterns in mortality concentration might reveal areas where successful public health interventions have been implemented. Translating these successes to locations where certain causes of death remain entrenched can inform policies that work to improve life expectancy for people everywhere. FUNDING Bill & Melinda Gates Foundation