6 research outputs found
A Novel Approach to the Synthesis of Some 2-Aryl Alkanoic Acid Esters
No full textA novel route to the synthesis of some 2-aryl alkanoic acid esters has been achieved. Aromatic nucleophilic substitution of various arene cyclopenta-dienyliron complexes with ethyl ethylacetoacetate and ethyl methylacetoacetate produced the complexed alkanoic acid esters. Photolysis of these complexes resulted in the liberation of the free esters in good yields
Two essays on innovations and accounting
No full textThis dissertation consists of two essays on innovations and accounting. The first essay aims to tackle the long-standing debate on the association between business risk and audit fee (e.g., Johnstone 2000; Morgan and Stocken 1998; Simunic and Stein 1994; Seetharaman, Gul, and Lynn ; 2002). Much of the prior literature on business risk focuses on litigation risk, which is the risk of incurring liability payments and the risk of damaged reputation for the service auditors provide. This study also follows the approach used in litigation risk studies but examines a topic that, to my knowledge, has not been explored in the literature. I examine whether the business risk (patent infringement risk) of innovation firms that may or may not be reflected in the financial reports, are associated with audit fees. The abstract nature of patents and institutional inefficiency of the existing patent system make patenting activities risky endeavors. First, the abstract nature of patents makes it challenging to clearly identify one patent from another; and existing patent system fails to establish clear boundaries and efficient guidelines to protect patented inventions. As a result, more than one entity can use or claim an invention at the same time, resulting in frequent and costly infringement suits. Second, patent infringement is a “strict liability” tort, and liability on patent infringements can be imposed on a party regardless of the party’s knowledge or intention (such as copying or bad faith or negligence). According to the 35 U.S. Code 271, a patent infringement occurs when another party makes, uses, or sells a patented item without the permission of the patent holder. Consequently, everyone up and down the supply chain could be sued for infringement. i.e., distributors can be sued for selling a patented invention, whereas end users can be sued for using the invention. Therefore, patenting activities involve potential business risks almost at every stage — from invention to production, to licensing and distribution. In addition to the direct legal cost, the aggregate costs of infringement suits include business costs such as loss of market share, management distractions, preliminary injunctions, negative publicity, temporary product boycotts, higher regulatory scrutiny and strained relationships with customers and industry members. Using the patenting activities and audit fees data of 3,688 firms in the U.S., I hypothesize and find that audit fees are higher for clients engaged in more patenting activities including the number of patents granted in a year and non-self-patent citations. The second essay examines whether internal controls enhance or impede firm innovations. Innovations begin at the individual level; and individual knowledge is transferred to the organization’s knowledge base only when it is shared and assimilated into routines, documents, and practices (Autio, Sapienza, and Almeida 2000). Therefore, as procedures designed to improve operational efficiency and effectiveness, internal control routines, documents and practices put in place can influence the innovation productivity of a firm. The COSO framework and recent studies in accounting suggest that strong internal controls increase investment efficiency and operational efficiency in a firm (COSO 1992; Cheng et. al. 2013; Feng et al. 2013). Literature from Total quality Management (TQM) and operations research also suggest that strong internal controls provide preventive mechanisms that minimize operating cost and business risk in the organization by eliminating costly and risky steps. Consequently, effective internal controls can enhance firm’s innovation productivity through increased operational efficiency and effectiveness, and reduced business risk For instance, effective control and monitoring mechanisms can minimize operating costs and operational risks related to defects, waste, reworks, delays, customer dissatisfaction and system failures; whereas strong information and communication system can facilitate a smooth and speedy transfer and assimilation of knowledge within and across units of organization. On the other hand, internal controls can also impede innovations as higher compliance costs divert scarce resources and management time from innovative undertakings. Moreover, in dynamic environments, formalized controls and monitoring routines may be far from optimal (Arthur 1994; Levitt and March 1988); and excessive focus on efficiency and effectiveness may induce certain dysfunctional behaviors in a firm that impede innovations including learning traps, structural inertia (rigidity), and compartmentalized thinking (Argyris & Schon, 1998; Dosi, 1998). Using a sample of 4,227 US firms that reported internal control under SOX 404, I find that firm innovation, measured by patenting activities, is significantly lower among firms with material internal control weaknesses relative to firms without such weaknesses. In addition, I find that firms that remediate their material internal control weaknesses subsequently experience an increase in innovation productivity.Ph.D.Includes bibliographical referencesby Tesfalidet Tuku
Evaluating gene expression patterns for NF-κB1, TNF, and VEGF A& VEGF B in a mouse model of SARS-CoV-2 infection
No full textIntroduction: The coronavirus disease (COVID-19) pandemic has encouraged extensive research into its pathophysiology, specifically the role of biomarkers in disease progression. Although TNF, NF-κB1, VEGF-A, and VEGF-B play fundamental roles in vascular development and the infection response, their precise involvement in COVID-19 remains unclear. We aimed to evaluate and synthesize TNF, NF-κB1, VEGF-A, and VEGF-B gene expression patterns in a mouse model of SARS-CoV-2 infection to understand their involvement in disease pathogenesis. Methods: Gene datasets available on the open-source Gene Expression Omnibus (GEO) platform were extracted from eleven specific datasets: GSE68220, GSE51387, GSE49262, GSE51386, GSE50000, GSE40824, GSE33266, GSE50878, GSE40840, GSE49263, and GSE40827. We used R 4.3.2 software in this analysis. Results: A Substantial changes in the expression of VEGFA, VEGFB, TNF-, and NF-κB1 were observed. Upregulation of TNF- and NF-κB1 implies a strong inflammatory response, consistent with their established involvement in inflammation. Conversely, VEGFA and VEGFB showed a pattern of downregulation, suggesting alterations in the vascular and endothelial functions. Conclusion: Substantial changes in TNF, NF-κB1, VEGFA, and VEGFB gene expression were observed During SARS-CoV infection, indicating their interconnected roles in disease pathogenesis. These findings improve our understanding of the molecular basis of COVID-19 vascular complications and will guide future research and therapies
Effectiveness of postoperative cephalosporins in reducing urinary tract infections and other parameters following transurethral resection of the prostate: a systematic review and meta-analysis
No full textBackgroundTransurethral resection of the prostate (TURP) is the standard surgical procedure for alleviating bladder obstruction caused by benign prostatic hyperplasia (BPH). Although effective, TURP is associated with the risk of urinary tract infection (UTI), which may be reduced by postoperative cephalosporin use.ObjectiveThis study aimed to determine the efficacy of cephalosporins in reducing the risk and complications of UTI following TURP.MethodsThe MEDLINE, Embase, and Cochrane Central databases were searched for randomized controlled trials (RCTs) that compared cephalosporin antibiotics with no intervention in patients undergoing TURP. The outcomes of interest for this systematic review and meta-analysis were UTI, length of stay, adverse effects, and postoperative days. Evaluations were reported as risk ratios (RR) and mean differences (MD) with 95% confidence intervals, using weighted random-effects models.ResultsThe Data Analysis included 668 participants from seven RCTs. Postoperative cephalosporin treatment after TURP significantly reduced the incidence of UTI compared with that in the control group (OR 0.37, 95% CI [0.22, 0.61], P<0.001, I²=30%). However, no significant difference was observed between postoperative cephalosporin use and the length of stay (MD -0.36, 95%CI [-1.13, 0.40], P=0.35, I²=81%), postoperative days (MD 0.20, 95% CI [-0.12, 0.53], P=0.22, I²=74%), and rate of adverse events (OR 0.94, 95% CI [0.58, 1.51], P=0.79; I²=0%).ConclusionCephalosporins effectively reduced the risk of UTI in patients undergoing TURP. Further research in this field is warranted to determine the efficacy of other antibiotics individually and provide a better comparison to implement standardized practices
Global, regional, and national disability-adjusted life-years (DALYs) for 333 diseases and injuries and healthy life expectancy (HALE) for 195 countries and territories, 1990-2016 : a systematic analysis for the Global Burden of Disease Study 2016
No full textBackground: Measurement of changes in health across locations is useful to compare and contrast changing epidemiological patterns against health system performance and identify specific needs for resource allocation in research, policy development, and programme decision making. Using the Global Burden of Diseases, Injuries, and Risk Factors Study 2016, we drew from two widely used summary measures to monitor such changes in population health: disability-adjusted life-years (DALYs) and healthy life expectancy (HALE). We used these measures to track trends and benchmark progress compared with expected trends on the basis of the Socio-demographic Index (SDI).
Methods: We used results from the Global Burden of Diseases, Injuries, and Risk Factors Study 2016 for all-cause mortality, cause-specific mortality, and non-fatal disease burden to derive HALE and DALYs by sex for 195 countries and territories from 1990 to 2016. We calculated DALYs by summing years of life lost and years of life lived with disability for each location, age group, sex, and year. We estimated HALE using age-specific death rates and years of life lived with disability per capita. We explored how DALYs and HALE differed from expected trends when compared with the SDI: the geometric mean of income per person, educational attainment in the population older than age 15 years, and total fertility rate.
Findings: The highest globally observed HALE at birth for both women and men was in Singapore, at 75.2 years (95% uncertainty interval 71.9-78.6) for females and 72.0 years (68.8-75.1) for males. The lowest for females was in the Central African Republic (45.6 years [42.0-49.5]) and for males was in Lesotho (41.5 years [39.0-44.0]). From 1990 to 2016, global HALE increased by an average of 6.24 years (5.97-6.48) for both sexes combined. Global HALE increased by 6.04 years (5.74-6.27) for males and 6.49 years (6.08-6.77) for females, whereas HALE at age 65 years increased by 1.78 years (1.61-1.93) for males and 1.96 years (1.69-2.13) for females. Total global DALYs remained largely unchanged from 1990 to 2016 (-2.3% [-5.9 to 0.9]), with decreases in communicable, maternal, neonatal, and nutritional (CMNN) disease DALYs offset by increased DALYs due to non-communicable diseases (NCDs). The exemplars, calculated as the five lowest ratios of observed to expected age-standardised DALY rates in 2016, were Nicaragua, Costa Rica, the Maldives, Peru, and Israel. The leading three causes of DALYs globally were ischaemic heart disease, cerebrovascular disease, and lower respiratory infections, comprising 16.1% of all DALYs. Total DALYs and age-standardised DALY rates due to most CMNN causes decreased from 1990 to 2016. Conversely, the total DALY burden rose for most NCDs; however, age-standardised DALY rates due to NCDs declined globally.
Interpretation: At a global level, DALYs and HALE continue to show improvements. At the same time, we observe that many populations are facing growing functional health loss. Rising SDI was associated with increases in cumulative years of life lived with disability and decreases in CMNN DALYs offset by increased NCD DALYs. Relative compression of morbidity highlights the importance of continued health interventions, which has changed in most locations in pace with the gross domestic product per person, education, and family planning. The analysis of DALYs and HALE and their relationship to SDI represents a robust framework with which to benchmark location-specific health performance. Country-specific drivers of disease burden, particularly for causes with higher-than-expected DALYs, should inform health policies, health system improvement initiatives, targeted prevention efforts, and development assistance for health, including financial and research investments for all countries, regardless of their level of sociodemographic development. The presence of countries that substantially outperform others suggests the need for increased scrutiny for proven examples of best practices, which can help to extend gains, whereas the presence of underperforming countries suggests the need for devotion of extra attention to health systems that need more robust support
Global, regional, and national incidence, prevalence, and years lived with disability for 328 diseases and injuries for 195 countries, 1990-2016 : a systematic analysis for the Global Burden of Disease Study 2016
No full textBACKGROUND: As mortality rates decline, life expectancy increases, and populations age, non-fatal outcomes of diseases and injuries are becoming a larger component of the global burden of disease. The Global Burden of Diseases, Injuries, and Risk Factors Study 2016 (GBD 2016) provides a comprehensive assessment of prevalence, incidence, and years lived with disability (YLDs) for 328 causes in 195 countries and territories from 1990 to 2016.METHODS: We estimated prevalence and incidence for 328 diseases and injuries and 2982 sequelae, their non-fatal consequences. We used DisMod-MR 2.1, a Bayesian meta-regression tool, as the main method of estimation, ensuring consistency between incidence, prevalence, remission, and cause of death rates for each condition. For some causes, we used alternative modelling strategies if incidence or prevalence needed to be derived from other data. YLDs were estimated as the product of prevalence and a disability weight for all mutually exclusive sequelae, corrected for comorbidity and aggregated to cause level. We updated the Socio-demographic Index (SDI), a summary indicator of income per capita, years of schooling, and total fertility rate. GBD 2016 complies with the Guidelines for Accurate and Transparent Health Estimates Reporting (GATHER).FINDINGS: Globally, low back pain, migraine, age-related and other hearing loss, iron-deficiency anaemia, and major depressive disorder were the five leading causes of YLDs in 2016, contributing 57·6 million (95% uncertainty interval [UI] 40·8-75·9 million [7·2%, 6·0-8·3]), 45·1 million (29·0-62·8 million [5·6%, 4·0-7·2]), 36·3 million (25·3-50·9 million [4·5%, 3·8-5·3]), 34·7 million (23·0-49·6 million [4·3%, 3·5-5·2]), and 34·1 million (23·5-46·0 million [4·2%, 3·2-5·3]) of total YLDs, respectively. Age-standardised rates of YLDs for all causes combined decreased between 1990 and 2016 by 2·7% (95% UI 2·3-3·1). Despite mostly stagnant age-standardised rates, the absolute number of YLDs from non-communicable diseases has been growing rapidly across all SDI quintiles, partly because of population growth, but also the ageing of populations. The largest absolute increases in total numbers of YLDs globally were between the ages of 40 and 69 years. Age-standardised YLD rates for all conditions combined were 10·4% (95% UI 9·0-11·8) higher in women than in men. Iron-deficiency anaemia, migraine, Alzheimer's disease and other dementias, major depressive disorder, anxiety, and all musculoskeletal disorders apart from gout were the main conditions contributing to higher YLD rates in women. Men had higher age-standardised rates of substance use disorders, diabetes, cardiovascular diseases, cancers, and all injuries apart from sexual violence. Globally, we noted much less geographical variation in disability than has been documented for premature mortality. In 2016, there was a less than two times difference in age-standardised YLD rates for all causes between the location with the lowest rate (China, 9201 YLDs per 100 000, 95% UI 6862-11943) and highest rate (Yemen, 14 774 YLDs per 100 000, 11 018-19 228).INTERPRETATION: The decrease in death rates since 1990 for most causes has not been matched by a similar decline in age-standardised YLD rates. For many large causes, YLD rates have either been stagnant or have increased for some causes, such as diabetes. As populations are ageing, and the prevalence of disabling disease generally increases steeply with age, health systems will face increasing demand for services that are generally costlier than the interventions that have led to declines in mortality in childhood or for the major causes of mortality in adults. Up-to-date information about the trends of disease and how this varies between countries is essential to plan for an adequate health-system response.FUNDING: Bill & Melinda Gates Foundation, and the National Institute on Aging and the National Institute of Mental Health of the National Institutes of Health
