cssi/SciSciGPT-SciSciNet huggingface dataset:
Admittance control for an electromechanical rowing machine

The paper considers a conceptual design for an electromechanical rowing machine and its control system. The concept includes a DC motor, a gear transmission, a drum and a pull cable. The force-velocity characteristic of a commercial rowing machine was modeled by a fourth-order mechanical admittance, and its parameters were identified from actual exercise data by a collocation method. The admittance controller is related to, and an extension of the natural admittance control proposed by Newman. The controller of this paper is able to achieve any desired target admittance for the electromechanical system at its mechanical (user) port, as long as the admittance is strictly proper. A fourth-order mechanical admittance was identified by the collocation method, with very good agreement to the data. The identified admittance was subsequently used as the target admittance of the electromechanical control system. A scale-size prototype was used to test the controller in a realtime experiment. Achievement of the target admittance was verified by simulating its response to the force profile of the experiment. The resulting velocity was in close agreement to that recorded from the experiment.
Role of Telomerase in Cancer Therapeutics

Telomerase is responsible for the maintenance of telomeres, specialized structures that cap the ends of chromosomes. Because most human cells lack telomerase, telomeres shorten each time cells divide and this attrition acts as a clock that limits their lifespan. During cancer development, this limited lifespan is almost always bypassed by the reactivation of telomerase, the enzyme responsible for the synthesis of telomeres. This upregulation of telomerase provides the cancer cells with cellular immortality or ability to proliferate for an unlimited number of cell divisions. Inhibitors of the enzyme telomerase have been developed to reverse this immortal phenotype and limit the lifespan of cancer cells. Following conventional chemotherapy, these inhibitors could be used to prevent the regrowth of residual disease and reduce the incidence of recurrence. In this chapter, we discuss the development of the first such inhibitor to enter clinical trials, GRN163L. The inhibitor, a lipid-conjugated oligonucleotide developed by Geron Corporation (Menlo Park, CA), inhibits telomerase in a wide range of cancer cell lines. In mice bearing human tumor cells, GRN163L can reduce tumor growth and metastasis. In this chapter, we discuss the development of GRN163L, its mechanism of action, and its potential value in the treatment of cancer patients. In the second half, we discuss anticipated challenges associated with the development of these new drugs, from the search for new compounds to the testing and optimization of current inhibitors.
Using phenomenological models for forecasting the 2015 Ebola challenge.

Abstract Background The rising number of novel pathogens threatening the human population has motivated the application of mathematical modeling for forecasting the trajectory and size of epidemics. Materials and methods We summarize the real-time forecasting results of the logistic equation during the 2015 Ebola challenge focused on predicting synthetic data derived from a detailed individual-based model of Ebola transmission dynamics and control. We also carry out a post-challenge comparison of two simple phenomenological models. In particular, we systematically compare the logistic growth model and a recently introduced generalized Richards model (GRM) that captures a range of early epidemic growth profiles ranging from sub-exponential to exponential growth. Specifically, we assess the performance of each model for estimating the reproduction number, generate short-term forecasts of the epidemic trajectory, and predict the final epidemic size. Results During the challenge the logistic equation consistently underestimated the final epidemic size, peak timing and the number of cases at peak timing with an average mean absolute percentage error (MAPE) of 0.49, 0.36 and 0.40, respectively. Post-challenge, the GRM which has the flexibility to reproduce a range of epidemic growth profiles ranging from early sub-exponential to exponential growth dynamics outperformed the logistic growth model in ascertaining the final epidemic size as more incidence data was made available, while the logistic model underestimated the final epidemic even with an increasing amount of data of the evolving epidemic. Incidence forecasts provided by the generalized Richards model performed better across all scenarios and time points than the logistic growth model with mean RMS decreasing from 78.00 (logistic) to 60.80 (GRM). Both models provided reasonable predictions of the effective reproduction number, but the GRM slightly outperformed the logistic growth model with a MAPE of 0.08 compared to 0.10, averaged across all scenarios and time points. Conclusions Our findings further support the consideration of transmission models that incorporate flexible early epidemic growth profiles in the forecasting toolkit. Such models are particularly useful for quickly evaluating a developing infectious disease outbreak using only case incidence time series of the early phase of an infectious disease outbreak.
Abstract TP387: An Interdisciplinary Approach to Improving Acute Treatment- Implementation of the Rapid Acute Stroke Protocol

Background: Recent emergence of evidence for the effectiveness of intra-arterial treatment (IAT) of acute ischemic stroke secondary to large vessel occlusion (LVO) has prompted hospitals to examine...
AN APPRAISAL OF STREET HAWKING AND PROSTITUTION IN ONITSHA ANAMBRA STATE

This paper is an appraisal of street hawking and prostitution. The problems of street hawking and prostitution, which exposes the individuals to the contraction and encourages the spread of sexual transmitted diseases, the paper is a response to the question to the factors that are responsible for street hawking and prostitution and the problem they face in trying to adjust to the status. Using the questionnaire method of eliciting information from respondence. Findings and recommendations where made.
Efficient collection and preparation of methane from low concentration waters for natural abundance radiocarbon analysis

Freshwater and marine environments constitute the largest global reservoirs of the greenhouse gas methane (CH4) and natural abundance radiocarbon measurements (14C-CH4) can allow for high confidence interpretations about CH4 dynamics operating in these environments. Collecting sufficient amounts of CH4 sample for a standard, high precision 14C-accelerator mass spectrometry (AMS) analysis (∼ 200 μg carbon (C)) was previously unfeasible when sampling from low CH4 concentration waters, such as much of the surface ocean (∼ 2 nM), which would require collecting the CH4 from 8500 L of seawater. The method described here involves pumping 20,000–40,000 L of seawater up from depth through a dissolved gas extraction system, which enables the collection of a sample composed of 100s of L of gas in less than 4 h on station. The large volume extracted gas sample is compressed into a 1.7 L cylinder for transport from the ship to the home laboratory. The home laboratory preparation of each sample to a CH4-derived carbon dioxide aliquot for 14C-AMS analysis is carried out in 3 h on a flow-through vacuum line that simultaneously prepares aliquots for stable isotope analyses (δ13C-CH4 and δ2H-CH4). The total process blank of the method is small (5.0 μg CH4-C) and composes 1.2% of the average collected and prepared sample (424 ± 163 μg, from a recent campaign; n = 16). The 14C-CH4 blanks prepared on the vacuum line have acceptably low 14C content (0.23 ± 0.07 percent Modern Carbon (pMC); n = 7) relative to the 14C-dead (0 pMC) CH4 from which they are prepared.
Characterization of Thermoelectric Ca3Co4O9 Microstructure Using Transmission Electron Microscopy

Ca 3 Co 4 O 9 (CCO), a misfit layered structure exhibiting large Seebeck coefficient at temperatures up to 1000 K has attracted increasing attention as a novel high-temperature thermoelectric material. In this work, we investigate bulk CCO as well as thin CCO films grown on SrTiO 3 (001) and Al 2 O 3 (0001) using pulsed laser deposition. Resulting crystal structure and quality of the samples is examined using high-resolution transmission electron microscopy in order to correlate with thermoelectric properties. HRTEM images show incommensurate stacks of CdI 2 -type CoO 2 layers alternating with rock-salt-type Ca 2 CoO 3 layers along the c-axis. A natural buffer layer about 10 nm thick was found present between CCO and SrTi 3 substrate accompanied by higher density of stacking faults. The CCO grown on Al 2 O 3 exhibited numerous misoriented grains, crystal defects and presence of Ca x CoO 2 phase.
Sex differences in microRNA-mRNA networks: examination of novel epigenetic programming mechanisms in the sexually dimorphic neonatal hypothalamus

Sexual differentiation of the male brain, and specifically the stress circuitry in the hypothalamus, is primarily driven by estrogen exposure during the perinatal period. Surprisingly, this single hormone promotes diverse programs of sex-specific development that vary widely between different cell types and across the developing male brain. The complexity of this phenomenon suggests that additional layers of gene regulation, including microRNAs (miRNAs), must act downstream of estrogen to mediate this specificity. To identify noncanonical mediators of estrogen-dependent sex-specific neural development, we assayed the miRNA complement of the mouse PN2 hypothalamus by microarray following an injection of vehicle or the aromatase inhibitor, formestane. Initially, multivariate analyses were used to test the influence of sex and experimental group on the miRNA environment as a whole. Then, we utilized traditional hypothesis testing to identify individual miRNA with significantly sex-biased expression. Finally, we performed a transcriptome-wide mapping of Argonaute footprints by high-throughput sequencing of RNA isolated by cross-linking immunoprecipitation (Ago HITS-CLIP) to empirically characterize targeting relationship between estrogen-responsive miRNAs and their messenger RNA (mRNA) targets. In this study, we demonstrated that the neonatal hypothalamic miRNA environment has robust sex differences and is dynamically responsive to estrogen. Analyses identified 162 individual miRNAs with sex-biased expression, 92 of which were estrogen-responsive. Examining the genomic distribution of these miRNAs, we found three miRNA clusters encoded within a 175-kb region of chromosome 12 that appears to be co-regulated by estrogen, likely acting broadly to alter the epigenetic programming of this locus. Ago HITS-CLIP analysis uncovered novel miRNA-target interactions within prototypical mediators of estrogen-driven sexual differentiation of the brain, including Esr1 and Cyp19a1. Finally, using Gene Ontology annotations and empirically identified miRNA-mRNA connections, we identified a gene network regulated by estrogen-responsive miRNAs that converge on biological processes relevant to sexual differentiation of the brain. Sexual differentiation of the perinatal brain, and that of stress circuitry in the hypothalamus specifically, seems to be particularly susceptible to environmental programming effects. Integrating miRNA into our conceptualization of factors, directing differentiation of this circuitry could be an informative next step in efforts to understand the complexities behind these processes.
Pure epistemic pluralism

Section 1 offers some stage setting. Pluralist views have recently attracted considerable attention in different areas of philosophy. Truth and logic are cases in hand. According to the alethic pluralist, there are several ways of being true. According to the logical pluralist, there are several ways of being valid. Section 2 introduces epistemic pluralism through the work of Tyler Burge, Alvin Goldman, and William Alston. In the work of these authors, we find pluralism about, respectively, epistemic warrant (Burge), justification (Goldman), and desiderata (Alston). Section 3 investigates what rationale can be given for epistemic pluralism. Drawing on the literature on truth pluralism, I suggest that one rationale for adopting a pluralist view in epistemology is its wider scope. Pluralism puts one in a position to accommodate a wider range of cases of epistemic assessments. In Sect. 4, I do two things. First, I explain why the distinction between epistemic monism and epistemic pluralism is most interestingly drawn at the level of non-derivative epistemic goods. Second, I make the observation that, at a very fundamental level, the varieties of epistemic pluralism presented in Sect. 2 are not particularly pure in nature. This is because they are all combined with veritic unitarianism, i.e. the view that there are several epistemic goods but that truth is the only non-derivative one. What, other than truth, might qualify as goods of this kind? Section 5 offers some preliminary considerations on this question, drawing on the work of Michael DePaul and Jonathan Kvanvig. In Sect. 6, I present two kinds of collapse arguments, each meant to show that pluralism is inherently unstable. I first consider each argument in the case of truth and then transpose them to epistemology. In Sect. 7, I respond to both collapse arguments.
Between “broken windows” and the “eyes on the street:” Walking to school in inner city San Diego

Abstract While research on active school travel usually focuses on physical activity benefits, this study proposes a conceptual framework to understand children's well-being, cognitive development, and community life associated with walking to school in an inner-city neighborhood. A series of children-centered activities (surveys, cognitive mapping, and focus groups) revealed that students who walk to school develop an acute understanding of their environment and a distinct sense of community. They feel comfortable with "eyes on the street" of residents, shopkeepers, and patrons but they express discomfort in the presence of "broken windows," i.e. cues of social disorder in the built environment. Their major concerns are about gangs and crime. Policies promoting walking to school should be responsive to these social milieu aspects and aim at communities' overall well-being rather than focusing just on children's physical health.
Optimziation Methods for Beacon Based Foraging Algorithms

Beacon-based Robotic foraging is inspired by nature’s ability to create efficient explorers and gatherers, and imposes a number of constraints on how agents can interact. In decentralized models, the robots must maintain chains of communication, effectively explore areas, and start collecting from discovered targets. Previous approaches have used a beacon-based technique, which is dependent on swarm size to environment size ratios, and do not have guarantees on finding all targets. This paper outlines the issues in these approaches and offers solutions to finding targets reliably, robust task allocations, and efficient beacon network. We verify our techniques by providing metrics of successful swarm size to environment size ratios, robot congestion improvement, and target utility independent measurements for gathering.
Choosing Wisely at the End of Life: Use of Shorter Courses of Palliative Radiation Therapy for Bone Metastasis.

Purpose American Society for Radiation Choosing Wisely guidelines recommend ≤10 fractions of radiation therapy (RT) for bone metastasis, with consideration for 1 fraction in patients with a poor prognosis. The purpose of this analysis was to evaluate characteristic differences in guideline concordance to fractionation regimens in a modern cohort of older patients with a diagnosis of bone metastasis. Methods and Materials Medicare beneficiaries aged ≥65 years treated with RT for bone metastasis from 2012 to 2015 were identified. Guideline-concordant RT fractionation was defined in the entire cohort as ≤10 fractions. Utilization of 1 fraction versus ≥2 fractions was analyzed in deceased patients. Patient demographic, disease, and facility characteristics associated with shorter fractionation were analyzed. Results In 569 patients treated with RT, the median age at diagnosis was 73 years. The most common cancer types were lung (37%), genitourinary (26%), breast (15%), and gastrointestinal (10%). Among all patients, 34%, 30%, and 36% received 1 fraction, 2 to 10 fractions, and ≥11 fractions, respectively. In comparison with receipt of 1 to 10 fractions, receipt of ≥11 fractions was associated with a $1467 increase in per-patient cost to Medicare during the calendar quarter of RT. Almost two-thirds of patients who died within 30 days of RT completion were treated with >1 fraction. Conclusions Although guideline concordance was high overall, a large number of patients received longer courses of RT at the end of life. Strong consideration should be made for utilization of shorter courses, particularly in patients with a limited prognosis.
On Modeling of Plasma Edge Conditions at Divertors with Solid Metal Neutralizers

AbstractIt is widely recognized that results from divertor models can be quite sensitive to the boundary conditions that are assumed at the divertor neutralizer plate. However, some past models assumed electron and ion heat transmission coefficients with little justification. In fact, energy and momentum fluxes from backscattered neutral deuterium and tritium atoms can significantly contribute to the energy and momentum balance of the divertor plasma and consequently affect the estimates of steady-state plasma conditions. In illustration of this point, a two-point model similar to that of Galambos and Peng is rederived, including momentum and energy sources from charge-exchange and a self-consistent fluid treatment of the sheath heat transmission coefficients. Divertor conditions associated with the International Tokamak Reactor (INTOR) and International Thermonuclear Experimental Reactor (ITER)-like fusion reactors are estimated, and the effects of including the backscattered fluxes are discussed.
Management of the En Bloc Distal Ureter and Bladder Cuff During Retroperitoneoscopic Radical Nephroureterectomy

Radical nephroureterectomy with resection of the en bloc distal ureter and bladder cuff is the gold standard treatment option for most patients with upper urinary tract transitional cell carcinoma (TCC). Recurrence at the distal ureter and/or peiureteral bladder mucosa in the presence of ipsilateral upper urinary tract urothelial carcinoma has clinical significance. This procedure involves radical nephrectomy and en bloc distal ureterectomy with 2- to 3-cm-diameter bladder cuff, with special care to prevent urine spillage. We describe here our pure laparoscopic technique using two suprapubic transvesical ports, with cystoscopic secured detachment and ligation of the en bloc bladder cuff and juxtavesical ureter. This laparoscopic technique duplicates established principles of open radical nephroureterectomy.
Geriatrics Literature 2017 Year in Review.

We present 11 of the most effective articles from 2017 in geriatric medicine. Studies address topics including self‐driven advance care planning, unnecessary emergency department transfers from assisted living, effect of transcatheter aortic valve implantation on cognition, a modified Hospital Elder Life Program to reduce delirium after surgery, patient experience and provider understanding of nursing home placement, patient perspectives on recommendations to stop cancer screening, management of subclinical hypothyroidism, reduction of inappropriate medications in nursing homes, effect of lorazepam on end‐of‐life agitated delirium, and benefits of a novel exercise program on walking.
Knowledge-Based Service Provisioning in Multi-Domain Elastic Optical Networks

This paper presents a knowledge-based service provisioning framework for building intelligent multi-domain elastic optical networks (EONs). The proposed framework adopts the broker-based inter-domain networking paradigm and employs network monitoring and data analytics functions to enable multidomain EONs operating according to an observe-analyze-act cycle. Case studies on quality-of-transmission aware lightpath provisioning demonstrate the benefit of the proposed framework.
Revisiting Iterative Relevance Feedback for Document and Passage Retrieval

As more and more search traffic comes from mobile phones, intelligent assistants, and smart-home devices, new challenges (e.g., limited presentation space) and opportunities come up in information retrieval. Previously, an effective technique, relevance feedback (RF), has rarely been used in real search scenarios due to the overhead of collecting users' relevance judgments. However, since users tend to interact more with the search results shown on the new interfaces, it becomes feasible to obtain users' assessments on a few results during each interaction. This makes iterative relevance feedback (IRF) techniques look promising today. IRF has not been studied systematically in the new search scenarios and its effectiveness is mostly unknown. In this paper, we re-visit IRF and extend it with RF models proposed in recent years. We conduct extensive experiments to analyze and compare IRF with the standard top-k RF framework on document and passage retrieval. Experimental results show that IRF is at least as effective as the standard top-k RF framework for documents and much more effective for passages. This indicates that IRF for passage retrieval has huge potential.
Re-evaluating the reconstruction of Proto-Eskimo-Aleut

Abstract The relationship between Unangam Tunuu (Aleut) and Eskimo was established in the early 19th century, and the 20th century especially saw a number of efforts on the reconstruction of Proto-Eskimo-Aleut (PEA). Reconstruction has supported assumptions of a largely genealogical relationship between the EA languages, assumptions which include a long history of independent development in isolation from other languages and language families. The reconstruction of PEA, however, is incomplete; many apparent cognates have irregular or imperfectly understood sound correspondences. Furthermore, advances in archaeology and genetics have called into question many assumptions about EA prehistory and about the isolation or lack thereof of Unangam Tunuu. In this study, I re-examine the proposed cognates and evaluate them based on the strength of their correspondences and their distribution within the lexicon, with reference to new findings regarding technological innovations and periods of cultural contact. Several patterns emerge, including a large group of proposed cognates with overly-specific semantic correlations relating to technologies or cultural practices post-dating the split of EA languages, a gender-based difference in the number of cognates relating to cultural activities, and a correlation between known borrowings and high levels of cognates in certain semantic domains. Results suggest extensive language contact, especially in the past millennium.
A High-throughput qPCR-based Method to Genotype the SOD1G93A Mouse Model for Relative Copy Number

The most commonly used mouse model in ALS preclinical research expresses multiple copies of the human SOD1 (G93A) transgene. During the course of breeding, successive generations of mice can lose copies of the transgene. Because shorter lifespan of these mice is dependent on transgene copy number, it is essential to ensure that no low-copy, and therefore longer-lived, mice are included in preclinical studies. Existing techniques for SOD1G93A mouse genotyping are broadly based on creating a standard curve using a reference gene and deducing the relative amount of SOD1 by comparison with the standard curve. This type of technique is used in Alexander et al. (2004) , Vieira et al. (2017) and Maier et al. (2018) . However, it is not described in detail (see Note 1). This paper provides a detailed protocol for determining the relative copy number of the human SOD1 transgene. Briefly, the protocol involves first the extraction of high-quality genomic DNA from mouse ear tissue, creation of a genomic DNA concentration-based standard curve, and qPCR analysis of up to 88 samples at once alongside the standard curve with Gapdh as a reference gene. Analysis involves the normalization of each unknown sample using the standard curve followed by determination of the copy number of the sample relative to the cohort median. This protocol has been optimized to produce high-quality genomic DNA and consistent results, and the relative copy number cutoffs have been optimized and validated empirically by comparison of relative copy number and mouse lifespan.
Multiscale Characterization of Lignocellulosic Biomass Variability and Its Implications to Preprocessing and Conversion: a Case Study for Corn Stover

Feedstock variability that originates from biomass production and field conditions propagates through the value chain, posing a significant challenge to the emerging biorefinery industry. Variability in feedstock properties impacts feeding, handling, equipment operations, and conversion performance. Feedstock quality attributes, and their variations, are often overlooked in assessing feedstock value and utilization for conversion to fuels, chemicals, and products. This study developed and employed a multiscale analytical characterization approach coupled with data analytic methods to better understand the sources and distribution of feedstock quality variability through evaluation of 24 corn stover bales collected in 4 counties of Iowa. In total, 216 core samples were generated by sampling nine positions on each bale using a reliable bale coring process. The samples were characterized for a broad suite of physicochemical properties ranging across field and bale, macro, micro, and molecular scales. Results demonstrated that feedstock quality attributes can vary at all spatial scales and that multiple sources of variability must be considered in order to establish and manage biomass quality for conversion processes.
Alternating magnetic field mediated release of fluorophores from magnetic nanoparticles by hysteretic heating

Abstract This study explores the use of differential heating of magnetic nanoparticles with different sizes and compositions (MFe2O4 (M = Fe, Co)) for heteroplexed temporal controlled release of conjugated fluorophores from the surface of nanoparticles. By exploiting these differences, we were able to control the amount of hysteretic heating occurring with the distinct sets of magnetic nanoparticles using the same applied alternating magnetic field radio frequency (AMF-RF). Using thermally labile retro-Diels-Alder linkers conjugated to the surface of nanoparticles, the fluorescent payload from the different nanoparticles disengaged when sufficient energy was locally generated during hysteretic heating. 1H, 13C NMR, ESI-MS, and SIMS characterized the thermally responsive fluorescent cycloadducts used in this study; the Diels Alder cycloadducts were modeled using density functional theory (DFT) computations. The localized point heating of the different nanoparticle compositions drove the retro-Diels-Alder reaction at different times resulting in higher release rates of fluorophores from the CoFe2O4 compared to the Fe3O4 nanoparticles.
Evidence for Splitting in the Q Region of K + π + π − Mass

We observe a splitting in the ${K}^{+}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ mass spectrum in ${K}^{+}d$ interactions at $9 \frac{\mathrm{GeV}}{c}$. We find a mass of $1243\ifmmode\pm\else\textpm\fi{}8 \frac{\mathrm{MeV}}{{c}^{2}}$ and a width of ${70}_{\ensuremath{-}18}^{+26}$ for the lower mass state, and a mass of 1344 \ifmmode\pm\else\textpm\fi{} 8 and a width of less than $60 \frac{\mathrm{MeV}}{{c}^{2}}$ for the higher mass state. The isospin of both states is determined to be \textonehalf{}. The results can be interpreted as evidence for the mixing of two ${J}^{P}={1}^{+} {K}^{*}$ states.
Diversity of insulin and IGF signaling in breast cancer: Implications for therapy

This review highlights the significance of the insulin receptor (IR) and insulin-like growth factor-1 receptor (IGF-1R) signaling pathway in cancer and assesses its potential as a therapeutic target. Our emphasis is on breast cancer, but this pathway is central to the behavior of many cancers. An understanding of how IR/IGF-1R signaling contributes to the function of the normal mammary gland provides a foundation for understanding its aberrations in breast cancer. Specifically, dysregulation of the expression and function of ligands (insulin, IGF-1 and IGF-2), receptors and their downstream signaling effectors drive breast cancer initiation and progression, often in a subtype-dependent manner. Efforts to target this pathway for the treatment of cancer have been hindered by several factors including a lack of biomarkers to select patients that could respond to targeted therapy and adverse effects on normal metabolism. To this end, we discuss ongoing efforts aimed at overcoming such obstacles.
Characterization of tissue-mimicking phantoms for evaluating photoacoustic microscopy image quality

Photoacoustic imaging (PAI) and photoacoustic microscopy (PAM) continue to undergo advancement, but standardized performance test methods are needed to facilitate development and translation. Most tissue-mimicking materials (TMMs) have not been adequately characterized at high acoustic frequencies relevant to PAM systems (>20 MHz). We characterized acoustic properties of various polyacrylamide TMM formulations over 10-60 MHz using a pulse-echo method, while optical properties were characterized over 400-1000 nm. We evaluated performance of a custom PAM system using phantoms containing gold nanoparticles. Polyacrylamide had highly tunable acoustic properties similar to human skin, and performance tests provided key insights into PAM system performance.
Topography and crime in place: The effects of elevation, slope, and betweenness in San Francisco street segments

Few studies have investigated how features of the land surface and the street network affect spatial crime patterns. Accordingly, for the current study, we estimated negative binomial regression mo...
Is Deprotonation of the Oxygen-Evolving Complex of Photosystem II during the S 1 → S 2 Transition Suppressed by Proton Quantum Delocalization?

We address the protonation state of the water-derived ligands in the oxygen-evolving complex (OEC) of photosystem II (PSII), prepared in the S2 state of the Kok cycle. We perform quantum mechanics/molecular mechanics calculations of isotropic proton hyperfine coupling constants, with direct comparisons to experimental data from two-dimensional hyperfine sublevel correlation (HYSCORE) spectroscopy and extended X-ray absorption fine structure (EXAFS). We find a low-barrier hydrogen bond with significant delocalization of the proton shared by the water-derived ligand, W1, and the aspartic acid residue D1-D61 of the D1 polypeptide. The lowering of the zero-point energy of a shared proton due to quantum delocalization precludes its release to the lumen during the S1→ S2 transition. Retention of the proton facilitates the shuttling of a proton during the isomerization of the tetranuclear manganese-calcium-oxo (Mn4Ca-oxo) cluster, from the "open" to "closed" conformation, a step suggested to be necessary for oxygen evolution from previous studies. Our findings suggest that quantum-delocalized protons, stabilized by low-barrier hydrogen bonds in model catalytic systems, can facilitate the accumulation of multiple oxidizing equivalents at low overpotentials.
Impact of Limited English Proficiency on Definitive Care in Pediatric Appendicitis.

Abstract Background Limited English proficiency (LEP) is associated with decreased access to healthcare. We hypothesized that LEP children with appendicitis would experience more delays in care than EP children. Methods Retrospective review of patients Results A total of 893 patients with appendicitis were identified, 15.6% (n = 140) had LEP. On multivariate regression LEP was not a significant predictor of appendiceal perforation (AOR 1.20, 95% CI 0.79, 1.80, P = 0.390). LEP was a significant predictor of a prior ED or pediatrician visit without definitive management (AOR 2.05, 95 % CI 1.05, 3.98, P= 0.034) and longer LOS (Coefficient 1.01, 95% CI 0.41, 1.61, P= 0.001). LEP was associated with a minimal increase in duration of pain prior to presentation that was not clinically significant and was not associated with initial operative or non-operative management or a significantly longer time between presentation and operation. Conclusions LEP children did not experience higher rates of appendiceal perforation at our institution, but were more frequently initially evaluated by a pediatrician or at an ED and discharged without definitive management and had longer LOS.
Factors Associated With Longitudinal Psychological and Physiological Stress in Health Care Workers During the COVID-19 Pandemic: Observational Study Using Apple Watch Data.

Background: The COVID-19 pandemic has resulted in a high degree of psychological distress among health care workers (HCWs). There is a need to characterize which HCWs are at an increased risk of developing psychological effects from the pandemic. Given the differences in the response of individuals to stress, an analysis of both the perceived and physiological consequences of stressors can provide a comprehensive evaluation of its impact. Objective: This study aimed to determine characteristics associated with longitudinal perceived stress in HCWs and to assess whether changes in heart rate variability (HRV), a marker of autonomic nervous system function, are associated with features protective against longitudinal stress. Methods: HCWs across 7 hospitals in New York City, NY, were prospectively followed in an ongoing observational digital study using the custom Warrior Watch Study app. Participants wore an Apple Watch for the duration of the study to measure HRV throughout the follow-up period. Surveys measuring perceived stress, resilience, emotional support, quality of life, and optimism were collected at baseline and longitudinally. Results: A total of 361 participants (mean age 36.8, SD 10.1 years; female: n=246, 69.3%) were enrolled. Multivariate analysis found New York City’s COVID-19 case count to be associated with increased longitudinal stress (P=.008). Baseline emotional support, quality of life, and resilience were associated with decreased longitudinal stress (P<.001). A significant reduction in stress during the 4-week period after COVID-19 diagnosis was observed in the highest tertial of emotional support (P=.03) and resilience (P=.006). Participants in the highest tertial of baseline emotional support and resilience had a significantly different circadian pattern of longitudinally collected HRV compared to subjects in the low or medium tertial. Conclusions: High resilience, emotional support, and quality of life place HCWs at reduced risk of longitudinal perceived stress and have a distinct physiological stress profile. Our findings support the use of these characteristics to identify HCWs at risk of the psychological and physiological stress effects of the pandemic.
A contribution to the embryology ofOlax wightiana wall

The floral parts arise in acropetal succession. Unicellular hairs are distributed over the floral parts. Plenty of tannin cells are found. The wall of the anther consists of five layers external to the tapetum. The tapetal cells are uninucleate at first, but later become binucleate, and are of the glandular type. The endothecium and the layer immediately below it are fibrillar. The microspores are arranged tetrahedrally, but occasionally show a decussate arrangement. The pollen grains have three and occasionally four pores and they are two-celled at the time of shedding.
CF healthcare workers feel unprepared in providing suitable end of life care and desire more education: Results of a nationwide survey.

Abstract Introduction Little is known about the depth of knowledge and preparedness of CF caregivers in delivering end of life and palliative care to CF patients and families. Method Nationwide survey questionnaires for CF care providers using the CF Foundation Listserv electronic web-based tool. Results The majority of non-physician CF care providers (55%) had more than 15years of experience in their discipline and 84% of physician had greater than 15years of experience. The majority reported that they felt "somewhat" or "very" involved in palliative or end of life care in their current role. Yet, when asked whether they felt adequately prepared to deliver palliative and end of life care, only 18% reported that they were "fully prepared" and 45% felt that they were only "minimally" or "not" prepared. Further, only one third of respondents received more than 10h of education in general palliative or end-of-life care, while only 10% had received more than 10h of education specific to CF end of life care. The majority (73%) of CF healthcare providers preferred more education specific to CF end of life care. Conclusion CF healthcare providers are involved in CF end of life issues but a fair number did not understand their role and felt inadequately prepared in delivering suitable end of life and palliative care. Many desired more education in the provision of such care.
Popularity weighted ranking for academic digital libraries

We propose a popularity weighted ranking algorithm for academic digital libraries that uses the popularity factor of a publication venue overcoming the limitations of impact factors. We compare our method with the naive PageRank, citation counts and HITS algorithm, three popular measures currently used to rank papers beyond lexical similarity. The ranking results are evaluated by discounted cumulative gain(DCG) method using four human evaluators. We show that our proposed ranking algorithm improves the DCG performance by 8.5% on average compared to naive PageRank, 16.3% compared to citation count and 23.2% compared to HITS. The algorithm is also evaluated by click through data from CiteSeer usage log.
Characterization of Boar Sperm Plasma Membranes by Two-dimensional PAGE and Isolation of Specific Groups of Polypeptides by Anion Exchange Chromatography and Lectin Affinity Chromatography

High resolution, two-dimensional PAGE was used to characterize purified plasma membranes (PM) from boar spermatozoa. In addition to the abundance of polypeptides resolved, unusual features of PM discerned in gel patterns include a large number of basic polypeptides and the presence of at least three polypeptides with molecular weights in excess of 200 K daltons. In order to reduce these large numbers of polypeptides into smaller fractions, an important step in developing a surface map of these membranes, detergent-solubilized membranes were fractionated by the techniques of ion exchange chromatography and lectin affinity chromatography. PM polypeptides, solubilized in the nonionic detergents, were fractionated on DEAE Sephadex using phosphate ion gradients containing EDTA. Most of the major acidic polypeptides were eluted as a group at high phosphate ion concentrations. Membrane polypeptides can be separated into smaller populations by affinity chromatography on wheat germ agglutinin-agarose (WGA) or by Concanavalin A-agarose. Concanavalin A-agarose binds most PM glycoproteins, but partial purification of an important group of very basic proteins was obtained by repeated chromatography of polypeptides that failed to bind to this lectin. Since biologic activity (including immunologic potency) is often retained in the detergents used, the ability to fractionate the major polypeptide of the boar sperm PM into different and much smaller populations in large quantity and to characterize these proteins by electrophoresis provides a starting point for determining the functional significance and location of the major surface proteins of the boar sperm PM.
Microbial Biotechnology: Biocatalysis in Organic Chemistry

In carrying out their metabolic processes, microorganisms interconvert diverse organic compounds. These “biotransformations” are catalyzed with high specificity and efficiency by enzymes. The active site of an enzyme, where substrate binding and catalysis are carried out, is an asymmetric surface whose special geometry frequently guarantees that the enzymecatalyzed reaction will yield a particular stereoisomer as the sole product. Such stereospecific, or enantioselective, reactions may be difficult or impossible to achieve by purely chemical means. The terms used to describe the stereochemistry of organic compounds are defined in Box 11.1, and the determination of enantioselectivity is described in Box 11.2. Even when an organic compound can be synthesized chemically, the process may require many steps, whereas a single enzyme-catalyzed reaction can often achieve the same end. Also, enzymes can catalyze reactions at ambient temperature, away from extremes of pH, and at atmospheric pressure. Undesired isomerization, racemization, epimerization, and rearrangement reactions that are frequently encountered during chemical processes are generally avoided. The absence of such side reactions is a particular advantage when the desired product is rather labile. Finally, enzymes can accelerate the rates of chemical reactions by factors of 10 8 to 10 12 . For all these reasons, biotransformations by microorganisms, or by enzymes purified from microorganisms, are highly useful in preparative organic chemistry. Certain disadvantages do limit the use of enzymes in organic chemical processes, but these limitations have frequently proved to be surmountable challenges rather than impenetrable barriers.
Terrestrial isotopic evidence for a Middle-Maastrichtian warming event from the lower Cantwell Formation, Alaska

Abstract Carbon stable isotope data (δ13C) and new radiometric dates indicate that the non-marine Late Cretaceous lower Cantwell Formation, central Alaska, registers the Middle-Maastrichtian Event (MME), a global warming episode. A stratigraphic section measured at the East Fork of the Toklat River in Denali National Park & Preserve includes a bentonite layer that we have dated to 69.5 ± 0.7 Ma using U–Pb isotope analysis of zircons. The new depositional age confirms that dinosaur tracks from the lower Cantwell Formation are coeval with dinosaur bones from outcrops of the Prince Creek Formation on Alaska's North Slope. δ13C data from fossil wood recovered from the lower Cantwell Formation records an ~ 3‰ positive excursion correlative with positive excursions from terrestrial and marine sections in West Texas (USA) and Gubbio (Italy), respectively. The similarity between marine and terrestrial records suggests that this excursion is the result of a major perturbation in the global carbon cycle, known as the Middle-Maastrichtian Event (MME). Mean annual precipitation (MAP) estimates calculated from δ13C data yield a range of 168–470 mm/yr during the MME, 353–1050 mm/yr before and 475–1451 mm/yr after the warming event. The δ13C record from the lower Cantwell Formation provides the first terrestrial high-latitude evidence for the MME, while MAP estimates for the coeval Prince Creek Formation suggest that the arctic coast may have been more humid than southern interior Alaska during the Middle Maastrichtian.
Low power scalable encryption for wireless systems

Secure transmission of multimedia information (e.g., voice, video, data, etc.) is critical in many wireless network applications. Wireless transmission imposes constraints not found in typical wired systems such as low power consumption, tolerance to high bit error rates, and scalability. A variety of low power techniques have been developed to reduce the power of several encryption algorithms. One key idea involves exploiting the variation in computation requirements to dynamically vary the power supply voltage. Application of low power techniques to a wireless camera application yield more than an order of magnitude reduction in power consumption over conventional design methods. Test circuits for five algorithms have been fabricated in a 0.6 um process and the resulting power consumption of each is presented. In addition, a low power hybrid system that combines a power-efficient keystream generator with a secure pseudo-random seed generator is proposed that provides 1 Mbps data encryption at a total estimated power consumption of 150 uW.
Calmodulin antagonists inhibit germination of Bacillus cereus T spores

The effects of two calmodulin antagonists, trifluoperazine (TFP) and N-(6-aminohexyl)-5-chloro-1-naphthalene sulphonamide hydrochloride (W-7) on L-alanine-induced germination of Bacillus cereus T spores were examined by measuring commitment to germination, decrease in optical density at 660 nm and phase-contrast microscopy. The kinetics of optical density decrease suggested competitive inhibition of TFP or W-7 with both L-alanine and D-alanine (L-alanine analogue and germination inhibitor) as determined by Lineweaver-Burk and Schild plots, respectively. Germination inhibition was pH-dependent. The I50 values for maximum decreasing rate of optical density in 10 mmol/l L-alanine plus 5 mmol/l adenosine at pH 6·4 were 0·21 and 0·74 mmol/l for TFP and W-7, respectively. Much less effect of N-(6-aminohexyl)-l-naphthalene sulphonamide hydrochloride than W-7 lends support to the specificity of W-7. The calmodulin antagonists were effective at a step in germination after commitment and loss of heat resistance. It is postulated that this process is necessary in the germination of B. cereus T spores to convert phase-bright spores to phase-dark spores and to cause a decrease in optical density.
Oligonucleotide therapy of allergic asthma

The recent increase in the prevalence of and mortality from asthma has inspired several new molecular techniques to improve treatment. Because asthma is a disease of gene polymorphism, gene therapy is unlikely to be effective. Alternative methods use oligonucleotides (ODNs) in the form of (1) DNA vaccination expressing CpG motifs that mimic bacterial DNA or (2) antisense ODNs inhaled and locally deposited into pulmonary airways to specifically modulate receptors for inflammatory mediators. DNA vaccination, a form of "molecular immune surveillance," attenuates a TH2 predominance. Antisense directed against the adenosine A(1 ) receptor abrogates A(1 ) sensitivity, improves allergen-induced immediate airway obstruction, and inhibits the expected increase in histamine responsiveness in allergic rabbits. Adenosine receptor inhibition lasts for an average of 7 days and the majority of the antisense remains in the lung. ODN therapy for asthma seem unlimited, but confirmation awaits the extension from animal models to human studies.
Keeping libraries relevant in the Semantic Web with resource description and access (RDA)

Cataloging is not just building a catalog, but about providing users with timely access to information relevant to their needs. The task of identifying resources collected by libraries, archives and museums results in rich metadata that can be reused for many purposes. It involves describing resources and showing their relationships to persons, families, corporate bodies and other resources, thereby enabling users to navigate through surrogates to more quickly get information they need. The metadata constructed throughout the life cycle of a resource is especially valuable to many types of users, from creators of resources to publishers, subscription agents, book vendors, resource aggregators, system vendors, libraries and other cultural institutions, and end users. The new international cataloging code, RDA (resource description and access), is designed to meet fundamental user tasks in a way that produces wellformed, interconnected metadata for the digital environment.