Clinical and Utilization Outcomes of Matched People With and Without HIV Aged 65+

The prevalence of age-standardized comorbidities is significantly elevated for PLWH across an array of cohorts. However, healthcare needs of older people living with (PLWH) and without (PWOH) HIV may be similar if they have similar geriatric conditions. PLWH and PWOH aged 65+ and eligible for Medicare from 7/1/2014-1/1/2015 were matched 1:1 on age, sex, race, and census region (n=7654). Cox regression assessed count of prevalent geriatric conditions (dementia, depression, falls, hip fracture, sensory deficits, osteoporosis, orthostatic hypotension, urinary incontinence, frailty, and polypharmacy), and risk for clinical or utilization outcomes (cancer, kidney disease, muscle wasting, hepatitis C, liver disease, myocardial infarction, stroke; hospitalization, nursing home and home health admission) during follow-up between 1/1/2015-12/31/2016. PLWH and PWOH are similar in count of geriatric conditions. Compared to those with none, those having 2+ geriatric conditions were similar across PLWH and PWOH in their risk of ≥1 clinical outcome (PLWH: HR 1.57 95% CI [1.29-1.90]; PWOH: HR 1.31 [1.02-1.67]), hospitalization (PLWH: HR 2.35 [1.96-2.83]; PWOH: HR 2.07 [1.65-2.60]), and home health admission (PLWH: HR 2.09 [1.58-2.76]; PWOH: HR 2.20 [1.55-3.12]). Having 2+ geriatric conditions, PWOH had 4.45 times the risk (95% CI 3.16-6.26) and PLWH had 2.88 times the risk (95% CI 2.18-3.81) of NH admission compared to no geriatric conditions. In this study, PLWH use nursing homes less than PWOH despite having a similar number of geriatric conditions and clinical outcomes. Further research to understand this apparent discrepancy will be critical to achieve equity in nursing home access.

Rapid adaptation often occurs through mutations to the most highly conserved positions of the RNA polymerase core enzyme

Mutations to the genes encoding the RNA polymerase core enzyme (RNAPC) and additional housekeeping regulatory genes were found to be involved in rapid adaptation, in the context of numerous evolutionary experiments, in which bacteria were exposed to diverse selective pressures. This provides a conundrum, as the housekeeping genes that were so often mutated in response to these diverse selective pressures tend to be among the genes that are most conserved in their sequences across the bacterial phylogeny. In order to further examine this apparent discrepancy, we characterized the precise positions of the RNAPC involved in adaptation to a large variety of selective pressures. We found that different positions of the RNAPC are involved in adaptation to various stresses, with very little overlap found between stresses. We further found that RNAPC positions involved in adaptation tended to be more evolutionary conserved, were more likely to occur within defined protein domains, and tended to be closer to the complex's active site, compared to all other RNAPC positions. Finally, we could show that this observed trend of higher conservation of positions involved in rapid adaptation extends beyond the RNAPC to additional housekeeping genes. Combined, our results demonstrate that the positions that change most readily in response to well defined selective pressures exerted in lab environments are also those that evolve most slowly in nature. This suggests that such adaptations may not readily occur in nature, due to their antagonistically pleiotropic effects, or that if they do occur in nature, they are highly transient.

Risk and Return Analysis for Companies Registered in the Iraq Stock Exchange Based on the Sortino and Sharpe Methods

The research aims to measure the return and risk in the Iraq Stock Exchange according to the modern portfolio theory (MPT) and post-modern portfolio theory (PMPT) and identify its difference. The study was recognized with several questions, the most important of which: "Is there a difference in measuring the return and risk between the modern portfolio theory and the post-modern portfolio theory?" The companies listed on the Iraq Stock Exchange were tested to answer this question. Seventy-two companies registered in the Iraq Stock Exchange from 2006 to 2019 has selected for this research sample. The accreditation was done on many financial and statistical indicators to analyze and interpret the results using Excel. According to the post-modern portfolio theory, the study found an apparent discrepancy in the values of the return and risk indicators compared to the modern portfolio theory due to the different philosophies and calculation methods in the portfolio's construction. This study can facilitate further studies and the investors looking forward to investing in the Iraqi stock exchange.

Evaluating Relaxations of Logic for Neural Networks: A Comprehensive Study

Symbolic knowledge can provide crucial inductive bias for training neural models, especially in low data regimes. A successful strategy for incorporating such knowledge involves relaxing logical statements into sub-differentiable losses for optimization. In this paper, we study the question of how best to relax logical expressions that represent labeled examples and knowledge about a problem; we focus on sub-differentiable t-norm relaxations of logic. We present theoretical and empirical criteria for characterizing which relaxation would perform best in various scenarios. In our theoretical study driven by the goal of preserving tautologies, the Lukasiewicz t-norm performs best. However, in our empirical analysis on the text chunking and digit recognition tasks, the product t-norm achieves best predictive performance. We analyze this apparent discrepancy, and conclude with a list of best practices for defining loss functions via logic.

Online-based Rubric for Peer Assessment: Effectiveness and Implications

This study investigates using technology to promote authentic and meaningful learning in applying a peer assessment rubric for a public speaking assessment in a higher education institution in Brunei Darussalam. Three hundred six undergraduates from Universiti Teknologi Brunei's Schools of Business, Computing, and the Engineering Faculty conducted the assessments in real-time using online-based rubrics accessible via their smartphones or laptops. Comparisons were made between the lecturers' marks and students for each rubric criterion, and a set of questionnaires was distributed to investigate students' perceptions toward the peer assessment after the assessment. The results indicated a variable discrepancy between assessments by the lecturers and students for the rubric criteria. While in some disciplines, peer marking was found to overmark compared to the lecturer by more than 15%, in other cases, the marks were similar. Comparison between peer and lecturer assessment indicated that the level of agreement was sensitive to the lecturer, but less so between student cohort when assessed by the same lecturer. When differences were observed, there was no apparent discrepancy in an agreement between aspects of the rubric which evaluated content or delivery. Students’ feedback revealed a positive response towards peer assessment but highlighted issues surrounding the technological aspects of the implementation process.

Viewpoint: Reply to Comment on 'Using NMR to Test Molecular Mobility During a Chemical Reaction'

Reports of boosted diffusion during chemical and enzymatic reactions have inspired a loyal community of scientists who find them so counter-intuitive that they must be artifact. This second Comment on the subject by these authors is about technicalities of how to analyze data we deposited online regarding J. Phys. Chem. Lett. (2021) 12, 2370 and Science (2020) 369, 537. Now that their own data is also online, one apparent discrepancy can be resolved: we demonstrate that the authors’ data agrees with ours because their first Comment on this subject reported only truncated short-time excerpts of the longer time series they deposited online (zenodo.org/record/4628353). This second Comment adds 5 additional objections, 4 of which are too technical to change the qualitative conclusion. The 5th objection errs because it omits to recognize intermediate states of the click reaction during which one reactant complexes with the catalyst to form an object of larger size. Elsewhere we analyzed in great detail the respective influences of boosted diffusion and this hydrodynamic effect (doi.org/10.26434/chemrxiv.14740563.v1). The factual evidence and reasoning in this Reply strongly support this laboratory’s earlier conclusions regarding boosted diffusion during common chemical reactions.

Viewpoint: Reply to Comment on 'Using NMR to Test Molecular Mobility During a Chemical Reaction'

Reports of boosted diffusion during chemical and enzymatic reactions have inspired a loyal community of scientists who find them so counter-intuitive that they must be artifact. This second Comment on the subject by these authors is about technicalities of how to analyze data we deposited online regarding J. Phys. Chem. Lett. (2021) 12, 2370 and Science (2020) 369, 537. Now that their own data is also online, one apparent discrepancy can be resolved: we demonstrate that the authors’ data agrees with ours because their first Comment on this subject reported only truncated short-time excerpts of the longer time series they deposited online (zenodo.org/record/4628353). This second Comment adds 5 additional objections, 4 of which are too technical to change the qualitative conclusion. The 5th objection errs because it omits to recognize intermediate states of the click reaction during which one reactant complexes with the catalyst to form an object of larger size. Elsewhere we analyzed in great detail the respective influences of boosted diffusion and this hydrodynamic effect (doi.org/10.26434/chemrxiv.14740563.v1). The factual evidence and reasoning in this Reply strongly support this laboratory’s earlier conclusions regarding boosted diffusion during common chemical reactions.

Biochemical Barriers on the Path to Ocean Anoxia?

The kinetics of microbial respiration suggest that, if excess organic matter is present, oxygen should fall to nanomolar levels, in the range of the Michaelis-Menten constants (Km). Yet even in many biologically productive coastal regions, lowest observed O2 concentrations often remain several orders of magnitude higher than respiratory Km values. We propose the Hypoxic Barrier Hypothesis (HBH) to explain this apparent discrepancy. The HBH postulates that oxidative enzymes involved in organic matter catabolism are kinetically limited by O2 at concentrations far higher than the thresholds for respiration. We found support for the HBH in a meta-analysis of 1137 O2 Km values reported in the literature: the median value for terminal respiratory oxidases was 350 nM, but for other oxidase types the median value was 67 µM. The HBH directs our attention to the kinetic properties of an important class of oxygen-dependent reactions that could help explain the trajectories of ocean ecosystems experiencing O2 stress.

Estrogens in Hepatocellular Carcinoma: Friends or Foes?

Estrogens are recognized as key players in physiological regulation of various, classical and non-classical, target organs, and tissues, including liver development, homeostasis, and function. On the other hand, multiple, though dispersed, experimental evidence is highly suggestive for the implication of estrogen in development and progression of hepatocellular carcinoma. In this paper, data from our own studies and the current literature are reviewed to help understanding this apparent discrepancy.

Towards Understanding the COVID-19 Case Fatality Rate

An important parameter for COVID-19 is the case fatality rate (CFR). It has been applied to wide applications, including the measure of the severity of the infection, the estimation of the number of infected cases, risk assessment etc. However, there remains a lack of understanding on several aspects of CFR, including population factors that are important to CFR, the apparent discrepancy of CFRs in different countries, and how the age effect comes into play. We analyze the CFRs at two different time snapshots, July 6 and Dec 28, with one during the first wave and the other a second wave of the COVID-19 pandemic. We consider two important population covariates, age and GDP as a proxy for the quality and abundance of public health. Extensive exploratory data analysis leads to some interesting findings. First, there is a clear exponential age effect among different age groups, and, more importantly, the exponential index is almost invariant across countries and time in the pandemic. Second, the roles played by the age and GDP are a little surprising: during the first wave, age is a more significant factor than GDP, while their roles have switched during the second wave of the pandemic, which may be partially explained by the delay in time for the quality and abundance of public health and medical research to factor in.