cssi/SciSciGPT-SciSciNet huggingface dataset:
A Universal Algorithm to Detect Rare or Novel Cell Types in High-Throughput Single-Cell Gene Expression Data

Abstract Detecting rare cell types would allow early disease detection of cancers and infections, identification of new cell types, and a deepened understanding of cell differentiation. We developed a universal algorithm to identify rare cell types from a wide variety of single-cell ’omics’ data. We validated our algorithm on single-cell qPCR data from mouse hematopoietic cells and single-cell RNA-seq data from human glioblastoma tumors cells, both with expression values from an ample number of genes. We then applied our algorithm to seq-FISH data from mouse hippocampus cells containing expression values from only 121 genes. Our algorithm detected rare cell types including a putative new hippocampal cell type. Author summary Rare cell type detection would advance early disease diagnosis (e.g., cancer, infection), allow identification of new cell types, and increase understanding of cell differentiation. Current computational methods can detect common cell types, but it remains a challenge to detect rare cell types within cell populations, especially with expression data from a relatively small number of genes. We created a powerful algorithm to detect rare cell types in a population of cells. We validated our algorithm on data from mouse blood stem cells and human glioblastoma tumors cells. When we applied our algorithm to mouse hippocampus data containing expression values from only 121 genes, we detected a putative new brain cell type that no previous algorithm has identified. Our universal algorithm can now be applied to a wide range of data to detect the early onset of diseases and discover new cell types.
Failure on the American board of surgery examinations of general surgery residency graduates correlates positively with states' malpractice risk

It has been suggested that in environments where there is greater fear of litigation, resident autonomy and education is compromised. Our aim was to examine failure rates on American Board of Surgery (ABS) examinations in comparison with medical malpractice payments in 47 US states/territories that have general surgery residency programs. We hypothesized higher ABS examination failure rates for general surgery residents who graduate from residencies in states with higher malpractice risk. We conducted a retrospective review of five-year (2010-2014) pass rates of first-time examinees of the ABS examinations. States' malpractice data were adjusted based on population. ABS examinations failure rates for programs in states with above and below median malpractice payments per capita were 31 and 24 per cent (P < 0.01) respectively. This difference was seen in university and independent programs regardless of size. Pearson correlation confirmed a significant positive correlation between board failure rates and malpractice payments per capita for Qualifying Examination (P < 0.02), Certifying Examination (P < 0.02), and Qualifying and Certifying combined index (P < 0.01). Malpractice risk correlates positively with graduates' failure rates on ABS examinations regardless of program size or type. We encourage further examination of training environments and their relationship to surgical residency graduate performance.
Continuous True-Time Delay Phase Shifter Using Distributed Inductive and Capacitive Miller Effect

A new true-time delay phase shifter concept is proposed exploiting the distributed Miller effect in coupled transmission lines. Simultaneous change in Miller capacitance and inductance controlled by a single analog voltage changes the propagation delay of a transmission line with constant input impedance and insertion loss. The true-time delay line feature of the proposed architecture accommodates a wide bandwidth signal without group delay distortion. A theoretical framework for understanding Miller inductance from voltage and current duality and the distributed Miller effect using coupled wave equations is presented. As a proof of concept, a four-stage tunable delay line with a high-speed phase modulation capability was fabricated in a 45-nm RF SOI CMOS process and occupies an active area of 0.28 mm2. The measured IC demonstrates a broadband tunable true-time delay with a measured group delay tuning range of 18 ± 1 ps from 11 to 24 GHz. The measured phase shift ranges are 173° and 182° with insertion losses of 10.6 ± 0.7 dB and 11.6 ± 1 dB at 28 and 30 GHz, respectively. The measured dc power consumption is 22 mW from a 1.2-V supply.
Avoidance of Overt Precipitation and Patient Harm Following Errant Y-Site Administration of Calcium Chloride and Parenteral Nutrition Compounded With Sodium Glycerophosphate

Calcium phosphate precipitates present 1 of many challenges associated with parenteral nutrition (PN) compounding. Extensive research has led to the establishment of solubility curves to guide practitioners in the prescription and preparation of stable PN. Concurrent dosing of intravenous products via y-site administration with PN can alter the chemical balance of the solution and modify solubility. Medications containing calcium or phosphate should not be administered in the same line as PN, due to the high potential for precipitation. Herein a case is reported from a pediatric cardiac intensive care unit where a physician ordered the administration of calcium chloride. The bedside nurse added the calcium chloride intermittent infusion as a y-site administration with the patient's PN. The patient's PN had been compounded with sodium glycerophosphate, temporarily available in the United States during a sodium phosphate shortage. The patient did not experience any observable adverse effects from the y-site administration with PN. Following this event, the scenario was replicated to investigate any precipitation risk associated with the y-site administration. Additionally, a separate PN solution containing sodium phosphate rather than glycerophosphate was compounded and used in a laboratory setting to demonstrate the potential for harm had the patient's PN been compounded with an inorganic phosphate source. This replication of the error demonstrates the additional safety gained in relation to precipitation risk when PN solutions are compounded with sodium glycerophosphate in place of sodium phosphate.
When in Doubt, Act! How Entrepreneurs’ Perceived Uncertainty Promotes Community Engagement

Entrepreneurial communities of inquiry are diverse, evolving bodies of potential customers, investors, collaborators, and other stakeholders with a shared interest in a potential opportunity. There...
In response to Luteijn et al.: Concerns regarding cGAMP uptake assay and evidence that SLC19A1 is not the major cGAMP importer in human PBMCs

Abstract We previously reported that SLC19A1 is an importer of the immunotransmitter 2’3’-cyclic-GMP-AMP (cGAMP)1 by performing a genome wide screen in U937 cells. Soon after, Lutejin et al. reported similar findings by conducting a screen in THP-1 cells2. While the conclusions of these two studies largely overlap, we arrived at significantly different conclusions regarding how broadly SLC19A1 is used by different cell types. Our study suggests that in addition to SLC19A1, many cultured and primary cell types use alternative, unidentified transporters to import cGAMP and other cyclic dinucleotides (CDNs). This conclusion was based on our findings that inhibition of SLC19A1 did not significantly reduce extracellular cGAMP signaling in multiple cell types, including primary CD14+peripheral blood mononuclear cells (PBMCs) from most donors. In contrast, Luteijn et al. concluded that SLC19A1 is the major CDN importer in humans, largely based on their use of a radiolabeled [32P] cGAMP uptake assay. Using this assay, they showed that inhibition of SLC19A1 abolishes [32P] uptake in total PBMCs. However, they did not test whether inhibition of SLC19A1 affects extracellular cGAMP signaling in these cells. Here, we highlight an important issue with the [32P] cGAMP uptake assay used by Luteijn et al. and demonstrate that measuring extracellular cGAMP signaling through the STING pathway is currently the best method for evaluating cGAMP import. We also show that inhibition of SLC19A1 has no effect on extracellular cGAMP signaling in total PBMCs, confirming that this cell type relies on other transport mechanisms for cGAMP import.
Student Information Use and Decision-Making in Innovation Competitions and the Impact of Librarian Interventions

At a large Midwestern university, librarians work closely with an annual undergraduate agricultural innovation competition to guide students through the process of conducting market research and as...
Teaching Cultural Studies in the Undergraduate Curriculum: From the Abstract to the Concrete, and Back Again

Now that almost half a century has passed since the first moment of the academic institutionalization of the field of cultural studies in the Centre of Contemporary Cultural Studies at Birmingham University in 1964, cultural studies is a more established, even “global,” intellectual phenomenon and practice in the academy. But while it is increasingly common to encounter cultural studies at the graduate level, the status and place of cultural studies at the undergraduate level remains, with few exceptions, largely uncertain. One notable exception is the relatively successful undergraduate program in cultural studies where the present author teaches. This chapter is a chronicle and contexualization of the curriculum of that program. The author discusses the challenges and merits of teaching cultural studies and critical theory in the context of a largely media and arts school in Chicago in an age of economic uncertainty and ballooning student debt. The aim is to generate and stimulate a productive conversation about the institutional, theoretical, and pedagogical challenges and rewards of such a project: cultural studies in the undergraduate curriculum.
Impact of a community-delivered parenting curriculum on perceived parenting stress and parent-reported outcomes in a low-income diverse population.

INTRODUCTION There is a need for effective, strengths-based parenting supports for diverse parent populations. We conducted a quasi-experimental study to investigate whether a 12-week parenting program delivered in the community decreases perceived parenting stress and improves parent-reported outcomes. METHOD Parents in the intervention group participated in Parenting Journey, a curriculum designed to increase resilience and support nurturing family relationships. Parents who were eligible for Parenting Journey but did not enroll were included in the concurrent comparison group. Participants completed the Parenting Stress Index and the Parenting Journey Survey at baseline and follow-up. We conducted bivariate and multivariate analyses to evaluate differences between groups. RESULTS We enrolled 244 parents, 123 in the intervention group and 121 in the comparison group. The majority of participants in the intervention and comparison groups were female, identified as Black or Latino, and reported an annual household income of less than $20,000. At baseline, intervention participants reported higher total parenting stress than comparison participants (mean percentile 70.7 vs. 55.8, p = .002). At follow-up, intervention participants' mean total parenting stress score decreased by 14.1 points, while comparison participants' score increased by 3.0 points (difference-in-difference p < .0001). Intervention participants were significantly more likely to demonstrate improvement in 4 or more of the 7 constructs measured by the Parenting Journey Survey (adjusted OR = 2.2, 95% CI [1.2, 4.1], p = .01). DISCUSSION Participation in Parenting Journey is associated with decreased perceived parenting stress and improvement in parent-reported outcomes. Future work should evaluate the longitudinal impact on parental mental health and child socioemotional development. (PsycInfo Database Record (c) 2020 APA, all rights reserved).
Abstract P5-08-18: Mortality rates associated with clinical and pathological characteristics of hormone receptor positive human epidermal growth factor receptor 2 negative early breast cancer: An analysis of the 2010-2016 surveillance, epidemiology, and end results data

Background: Breast cancer in the United States is diagnosed in over 90% of cases prior to evidence of distant metastasis (stages I–III) with approximately 70% of these cases classified as hormone receptor positive human epidermal growth factor receptor 2 negative (HR+HER2-).1 Despite primary surgery, radiation, and adjuvant endocrine/chemotherapy treatment options, approximately 20-30% of patients will experience relapse with distant metastases.2 Some clinical and pathological characteristics are known to be prognostic factors, but there are no standard definitions associated with level of risk. The objective of this study was to determine the extent of mortality associated with clinical and pathological characteristics of early breast cancer (EBC) using real-world data. Methods: Eligible patients from 2010–2016 Surveillance, Epidemiology, and End Results (SEER) data were aged ≥18 years and had a diagnosis of stage I, II, or III breast cancer with no distant metastases. Patients with HR-HER2- breast cancer were excluded. Mortality rates (95% confidence interval) by HER2 status and, for HR+HER2- tumors, by cancer stage, Bloom-Richardson (BR) grade, ipsilateral auxiliary lymph nodes status, and tumor size were estimated using Kaplan-Meier methods. Results: A total of 257,278 breast cancer patients were included: 214,578 HR+HER2-, 30,122 HR+HER2+, and 12,578 HR-HER2+. Mean age was 61.5 years, 99.1% were female, and 70.1% were white/non-Hispanic. The 5-year mortality rates were similar for HR+HER2- (12.3%) and HR+HER2+ (12.2%), whereas HR-HER2+ was numerically higher (16.8%). Within the HR+HER2- group, the 5-year mortality rates for subgroups are shown in Table 1. The highest mortality rate for both the node positive and micrometastases subgroups was approximately 30% for those who had 1–3 ipsilateral auxiliary lymph nodes, BR grade 3, and tumor size ≥5 cm. Conclusions: Patients with HR+HER2- EBC had similar mortality rates to patients with HR+HER2+ EBC. In patients with HR+HER2- EBC, higher mortality rates were numerically associated with ≥4 positive lymph nodes, BR grade 3, and greater tumor size. The effect on mortality was compounded with combinations of these histopathologic characteristics. References: 1. Howlander N, et al. J Natl Cancer Inst 2014;106:dju055; 2. Cardoso F, et al. Breast 2018;39:131-8. Citation Format: Jacqueline Brown, Michael W Method, David R Nelson. Mortality rates associated with clinical and pathological characteristics of hormone receptor positive human epidermal growth factor receptor 2 negative early breast cancer: An analysis of the 2010-2016 surveillance, epidemiology, and end results data [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P5-08-18.
Concentration polarization over reverse osmosis membranes with engineered surface features

Abstract Creating membranes with engineered surface features has been shown to reduce membrane fouling and increase flux. Surface feature patterns can be created by several means, such as thermal embossing with hard stamps, template-based micromolding, and printing. It has been proposed that the patterns create enhanced mixing and irregular fluid flow that increases mass transfer of solutes away from the membrane. The main objective of this paper is to explore whether enhanced mixing and improved mass transfer actually do take place for reverse osmosis (RO) membranes operated in laminar flow conditions typical of full-scale applications. We analyzed velocity, concentration, shear stress, and concentration polarization (CP) profiles for flat, nanopatterned, and micropatterned membranes using computational fluid dynamics. Our methods coupled the calculation of fluid flow with solute mass transport, rather than imposing a flux, as has often been done in other studies. A correlation between Sherwood number and mass-transfer coefficient for flat membranes was utilized to help characterize the hydrodynamic conditions. These results were in good agreement with the numerical simulations, providing support for the modeling results. Models with flat, several line and groove patterns, rectangular and circular pillars, and pyramids were explored. Feature sizes ranged from zero (flat) to 512 μm. The ratio of feature length, between-feature distance, and feature height was 1:1:0.5. Results indicate that patterns greatly affected velocity, shear stress, and concentration profiles. Lower shear stress was observed in the valleys between the pattern features, corresponding to the higher concentration region. Some vortices were generated in the valleys, but these were low-velocity flow features. For all of the patterned membranes CP was between 1% and 64% higher than the corresponding flat membrane. It was found that pattern roughness correlated with boundary layer thickness and thus the patterns with higher roughness caused lower mass transfer of solute away from the surface. Rather than enhancing mixing to redistribute solute, the patterns accumulated solute in valleys and behind surface features. Despite the elevated CP, the nominal permeate flux increased by as much as 40% in patterned membranes due to higher surface area compared to flat membranes. The advantageous results seen in other studies where patterns have helped increase flux may be caused by the additional surface area that patterns provide.
The value of ultrasound and MRI in the diagnosis of pulmonary sequestration

Objective To investigate the diagnostic value of ultrasound and MRI in fetal bronchopulmonary sequestration (BPS). Methods The 7 pregnant women with suspected fetal BPS were examined with a 1.5 T MR unit within 24 h after prenatal ultrasound in Hubei Maternal and Children's Hospital during July 2013 to February 2015. The imaging protocol included half-fourier acquisition single shot turbo SE (HASTE), true fast imaging with steady state precession (True FISP) in axial, frontal and sagittal planes relative to the fetal thorax. Prenatal MRI findings have been compared with postnatal enhanced computed tomography or biopsy. Results The locations of BPS were in left side in 5 cases and in right side in 2 cases. One case was complicated with congenital cystic adenomatoid malformation (CCAM) of lung. Ultrasound showed the intrathoracic mass as a hyperechoic lesion and the feeding artery could be found by Doppler ultrasonography. T2WI could reveal not only the hyperintense lesions with clear boundary, but also the hypointense feeding artery originating from systemic circulation. Compared with pathological examination or enhanced CT, both of the ultrasound and the MRI could locate the lesions; however 2 feeding arteries were misjudged. Conclusions Prenatal ultrasound is the first-choice diagnostic modality for BPS. MRI can demonstrate the location, morphology and the feeding arteries of the fetal BPS, and also estimate the volume of normal lungs, which could be an important supplement to prenatal ultrasound in prenatal diagnosis and prognostic prediction of BPS. Key words: Ultrasonography, prenatal; Magnetic resonance imaging; Fetus; Lung; Bronchopulmonary sequestration
Two new species of Heteranthera (Pontederiaceae) in North America

Two new species are here described as segregates from Heteranthera multiflora. Heteranthera missouriensis sp. nov. has 5–13 flowers on an elongate floral axis, lavender to purplish flowers, a smaller perianth with the tube 3–5 mm long and lobes 3–4.5 mm long; it is common in the southern Great Plains of North America. Heteranthera pauciflora sp. nov. has 3–6 flowers on a shortened floral axis, commonly enclosed by the subtending spathe, white to light lavender flowers with the tube 8–10 mm long; it is known from the Atlantic coast from New Jersey to North Carolina. A taxonomic key to all species of the genus in North America, and a modified description of Heteranthera multiflora, are provided.
What’s in a word? War, law and counter-terrorism

This chapter examines how a war conception impacts and interacts with counterterrorism so as to explore the consequences for law of the choice to view counterterrorism as war, or vice versa. How does the development and implementation of counterterrorism laws and measures differ between countries that view counterterrorism as war and those that take a law enforcement approach, for example? The first section examines three main areas where a war framework — or even the rhetoric of war — has significant consequences: detention, the use of force, and prosecutions. Law is a source of authority and a source of constraint at the same time, and one can see this tension in comparing how war, or the absence of war, impacts counterterrorism laws and policy in these three areas. In addition, the rhetorical effects of definitional choices in portraying “war”, “terrorism”, and “threat” to the public must not be underestimated.The second section of this chapter explores an area that proves equally fruitful in examining the impact of war determinations on counterterrorism activities. Although the overwhelming majority of the academic and policy discourse of the past decade-plus has focused on the United States pursuit of terrorists through military means, one should also consider the decision of several countries to characterize internal conflicts as counterterrorism operations, such as the Russians in Chechnya or the Sri Lankan government against the Tamil Tigers. Re-characterizing war as counterterrorism has significant consequences for the application of the law of armed conflict, the law that governs conduct during wartime, and therefore for the protection of persons and property and the possibilities for the use of international law as a bulwark against overweening governmental power.
Conceptualization and analysis of a novel combined sorption and phase-change material thermal storage system

Abstract A new sorption-based thermal storage cycle is proposed. Energy is stored chemically by separating the constituents of highly non-ideal solutions, yielding much lower stand-by losses than in conventional approaches. The cycle avoids limitations of previously proposed sorption-based storage cycles by using a liquid-liquid mixer, and does not require a thermal source during discharge. A criterion based on a second law analysis is developed to evaluate potential working fluids for the cycle. Different cycle configurations are analyzed. An enhanced combined sorption and phase-change material (PCM) cycle is also investigated and compared with conventional thermal storage systems. For delivering 100 GJ of energy after 8 months, the combined cycle has an efficiency of 11% and lower storage volumes (down to 0.1 ×) than conventional thermal storage technologies. The energy density of the combined sorption-PCM system is 30 kWh m − 3.
Going to University: The Influence of Higher Education on the Lives of Young South Africans

Going to University: The Influence of Higher Education on the Lives of Young South Africans is a great book written very well by the authors. The use of the narratives gives the book an engaging and readable quality that will make a reader to complete the reading. The authors narrated the interviews conducted with 73 young people six years after they enrolled at one of the urban schools in South Africa. As the book progresses, the authors further introduced us to 20 young people whose stories were narrated in detail.
A Psychometric Look at Principal Professional Development.

This study evaluates aspects related to P12 principals’ professional development needs in South Carolina regarding the three domains of school leadership: management, instructional leadership, and program administration. A survey to rate principals’ current leadership knowledge, rank order their professional development needs, and provide a confidence rating regarding their abilities was given to over 1,100 principals and 85 superintendents. Through examining relationships with a psychometric model, results derived latent leadership ability scores and self-reported confidence ratings of principals as well as the superintendents’ leadership scores and confidence ratings of their principals. This study found a significant discrepancy between principals’ and superintendents’ confidence ratings and their corresponding leadership ability scores, respectively. A further analysis of the rank-ordered professional development needs highlighted instructional leadership to be the most needed topic for professional development. Finally, atypical response patterns regarding principal’s current leadership knowledge are also identified through person-fit analysis to provide additional information regarding P-12 principals’ professional development needs.
Diabetes and pancreatic cancer: recent insights with implications for early diagnosis, treatment and prevention

Purpose of review Recent insights into the complex relationship between diabetes and pancreatic cancer have the potential to help direct future approaches to early detection, treatment and prevention. Recent findings Insulin resistance and hyperinsulinemia have been identified as factors that relate to risk of pancreatic cancer among patients with long-standing diabetes. In contrast, weight loss in the setting of new-onset diabetes can help identify patients at an increased risk for harbouring pancreatic-cancer related disturbances in glucose metabolism. Insights into the implications of poor glycaemic control in patients undergoing resection for pancreatic cancer have the potential to improve both surgical and oncologic outcomes. Finally, among antidiabetic medications, metformin continues to be evaluated as a potential adjunctive therapeutic agent, although recent evidence supports the safety of incretins with respect to pancreatic cancer. Summary This review highlights recent developments in these areas with an emphasis on opportunities for improved early diagnosis, treatment and prevention in pancreatic cancer.
Developing Foundations for Accountability Systems: Informational Norms and Context-Sensitive Judgments

Adequately protecting informational privacy in an increasingly interconnected world poses two problems. What are the appropriate privacy polices? And, how should one ensure compliance with them? Accountability systems are an attractive solution to both problems. Current work on accountability systems assumes a generally accepted set of privacy rules for the subsequent use of information, and has focused on developing a formal representation of a process for the use of information. Our focus is on fundamental policy issues that arise in developing the models of the privacy rules themselves. This focus leads to the suggestion that accountability systems can be used, not only to enforce compliance with a given set of rules but also to resolve conflicts among conflicting sets of rules. So far, accountability systems have modeled unrealistically simple privacy rules. While this may be an appropriate first step toward more complex systems, we need to define the realistic target at which accountability systems should ultimately aim if adequate systems are eventually to be developed. We specify a number of hurdles to developing accountability systems that adequately constrain the use of information. Some of the problems are wholly nontechnical; some are of a mixed nature, part social science or public policy and part technical. The unifying theme is the role of informational norms in ensuring adequate informational privacy.
Exploring spatial averaging of contamination in fomite microbial transfer models and implications for dose.

BACKGROUND When modeling exposures from contact with fomites, there are many choices in defining the sizes of compartments representing environmental surfaces and hands, and the portions of compartments involved in contacts. These choices impact dose estimates, yet there is limited guidance for selection of these model parameters. OBJECTIVE The study objective was to explore methods for representing environmental surface and hand contact areas in exposure models and implications for estimated doses. METHODS A simple scenario was used: an individual using their hands to contact their face and two microbially contaminated environmental surfaces. Four models were developed to explore different compartmentalization strategies: (1) hands and environmental surfaces each represented by one compartment, (2) hands represented by two compartments (fingertips vs. non-fingertip areas) while environmental surfaces were represented by one compartment, (3) hands represented by a single compartment and environmental surfaces represented by two compartments, and (4) hands and environmental surfaces each represented by two compartments. Sensitivity analyses were conducted to evaluate the influence of heterogeneous surface contact frequency, hand contact type, and hand dominance on dose. RESULTS Estimated doses were greatest when hand areas and environmental surfaces were each represented by two compartments, indicating that surface area "dilutes" contaminant concentration and decreases estimated dose. SIGNIFICANCE Model compartment designations for hands and environmental surfaces affect dose estimation, but more human behavior data are needed. IMPACT STATEMENT A common problem for exposure models describing exposures via hand-to-surface contacts occurs in the way that estimated contamination across human skin (usually hands) or across environmental surfaces is spatially averaged, as opposed to accounting for concentration changes across specific parts of the hand or individual surfaces. This can lead to the dilution of estimated contaminants and biases in estimated doses in risk assessments. The magnitude of these biases and implications for the accuracy in risk assessments are unknown. We quantify differences in dose for various strategies of compartmentalizing environmental surfaces and hands to inform guidance on future exposure model development.
SU-F-BRD-09: A Random Walk Model Algorithm for Proton Dose Calculation

Purpose: To develop a random walk model algorithm for calculating proton dose with balanced computation burden and accuracy. Methods: Random walk (RW) model is sometimes referred to as a density Monte Carlo (MC) simulation. In MC proton dose calculation, the use of Gaussian angular distribution of protons due to multiple Coulomb scatter (MCS) is convenient, but in RW the use of Gaussian angular distribution requires an extremely large computation and memory. Thus, our RW model adopts spatial distribution from the angular one to accelerate the computation and to decrease the memory usage. From the physics and comparison with the MC simulations, we have determined and analytically expressed those critical variables affecting the dose accuracy in our RW model. Results: Besides those variables such as MCS, stopping power, energy spectrum after energy absorption etc., which have been extensively discussed in literature, the following variables were found to be critical in our RW model: (1) inverse squared law that can significantly reduce the computation burden and memory, (2) non-Gaussian spatial distribution after MCS, and (3) the mean direction of scatters at each voxel. In comparison to MC results, taken as reference, for a water phantom irradiated by mono-energetic proton beams from 75 MeV to 221.28 MeV, the gamma test pass rate was 100% for the 2%/2mm/10% criterion. For a highly heterogeneous phantom consisting of water embedded by a 10 cm cortical bone and a 10 cm lung in the Bragg peak region of the proton beam, the gamma test pass rate was greater than 98% for the 3%/3mm/10% criterion. Conclusion: We have determined key variables in our RW model for proton dose calculation. Compared with commercial pencil beam algorithms, our RW model much improves the dose accuracy in heterogeneous regions, and is about 10 times faster than MC simulations.
Taking the Pit Bull Off the Leash: Siccing the Endangered Species Act on Climate Change

Environmentalists have been warning of catastrophic climate change for years, often getting only minimal attention from lawmakers and, until recently, the public. With the political climate still moving only incrementally, citizen groups and states may have a tactic in the Endangered Species Act to jumpstart the reduction of CO2 emissions. This Note examines the implications of a citizen suit to reduce emissions based on the section 9 “take” provisions of the Endangered Species Act. It examines Article III standing requirements alongside the citizen-suit provisions of the Endangered Species Act, and the possible existence of a nonjusticiable political question. The Note takes the position that such a suit could move forward successfully, given the right judicial circumstances.
In search of silver bullet (software engineering)

Summary form only given. The author examines the difficulties in solving the generic problem of finding reliable, efficient, timely, and cost-contained solutions for automation problems in software engineering. He notes that it is desirable to have a high-level description system that takes advantage of AI, SE, database-management systems, and graphics technologies for interactive and rapid development of functional prototypes. At the heart of such a system, there is an executable very-high-level design language which can be used in interactive, incremental, and hierarchical specification of large-scale systems. >
Receding horizon trajectory optimization in opportunistic navigation environments

Receding horizon trajectory optimization for optimal information gathering in opportunistic navigation environments is considered. A receiver is assumed to be dropped in an environment consisting of multiple signals of opportunity (SOPs) transmitters. The receiver has minimal a priori knowledge about its own states and the SOPs’ states. The receiver draws pseudorange observations from the SOPs. The receiver’s objective is to build a high-fidelity signal landscape map while simultaneously localizing itself within this map in space and time. Assuming that the receiver can control its maneuvers, the following two problems are considered. First, the minimal conditions under which the environment is completely observable are established. It is shown that receiver-controlled maneuvers reduce the minimal a priori information about the environment required for complete observability. Second, the trajectories that the receiver should traverse are prescribed. To this end, a one-step look-ahead (greedy) strategy is compared with a multistep look-ahead (receding horizon) strategy. The limitations and achieved improvements in the map quality and space-time localization accuracy due to the receding horizon strategy are quantified. The computational burden associated with the receding horizon strategy is also discussed.
Dysregulated Hepatic Methionine Metabolism Drives Homocysteine Elevation in Diet-Induced Nonalcoholic Fatty Liver Disease

Methionine metabolism plays a central role in methylation reactions, production of glutathione and methylarginines, and modulating homocysteine levels. The mechanisms by which these are affected in NAFLD are not fully understood. The aim is to perform a metabolomic, molecular and epigenetic analyses of hepatic methionine metabolism in diet-induced NAFLD. Female 129S1/SvlmJ;C57Bl/6J mice were fed a chow (n = 6) or high-fat high-cholesterol (HFHC) diet (n = 8) for 52 weeks. Metabolomic study, enzymatic expression and DNA methylation analyses were performed. HFHC diet led to weight gain, marked steatosis and extensive fibrosis. In the methionine cycle, hepatic methionine was depleted (30%, p< 0.01) while s-adenosylmethionine (SAM)/methionine ratio (p< 0.05), s-adenosylhomocysteine (SAH) (35%, p< 0.01) and homocysteine (25%, p< 0.01) were increased significantly. SAH hydrolase protein levels decreased significantly (p <0.01). Serine, a substrate for both homocysteine remethylation and transsulfuration, was depleted (45%, p< 0.01). In the transsulfuration pathway, cystathionine and cysteine trended upward while glutathione decreased significantly (p< 0.05). In the transmethylation pathway, levels of glycine N-methyltransferase (GNMT), the most abundant methyltransferase in the liver, decreased. The phosphatidylcholine (PC)/ phosphatidylethanolamine (PE) ratio increased significantly (p< 0.01), indicative of increased phosphatidylethanolamine methyltransferase (PEMT) activity. The protein levels of protein arginine methytransferase 1 (PRMT1) increased significantly, but its products, monomethylarginine (MMA) and asymmetric dimethylarginine (ADMA), decreased significantly. Circulating ADMA increased and approached significance (p< 0.06). Protein expression of methionine adenosyltransferase 1A, cystathionine β-synthase, γ-glutamylcysteine synthetase, betaine-homocysteine methyltransferase, and methionine synthase remained unchanged. Although gene expression of the DNA methyltransferase Dnmt3a decreased, the global DNA methylation was unaltered. Among individual genes, only HMG-CoA reductase (Hmgcr) was hypermethylated, and no methylation changes were observed in fatty acid synthase (Fasn), nuclear factor of kappa light polypeptide gene enhancer in B-cells 1 (Nfκb1), c-Jun, B-cell lymphoma 2 (Bcl-2) and Caspase 3. NAFLD was associated with hepatic methionine deficiency and homocysteine elevation, resulting mainly from impaired homocysteine remethylation, and aberrancy in methyltransferase reactions. Despite increased PRMT1 expression, hepatic ADMA was depleted while circulating ADMA was increased, suggesting increased export to circulation.
Expanding entrepreneurship opportunities through local governance: the case of Barbados

This paper looks at the government and local governance structures of Barbados, arguing that local governance should be leveraged to expand entrepreneurship opportunities at the community level. It examines the links between local governance and entrepreneurship, and proposes a framework aimed at strengthening the relationship between Barbados’ newly formed constituency councils and its government institutions supporting entrepreneurship. The research concludes that there are many inefficiencies in the interaction between government agencies and constituency councils, which the proposed framework is a first step toward remedying. The research suggests that local governance is a complex issue worldwide. More specifically in Barbados, even though the role of the constituency councils is defined, there are weak formal arrangements which undermine the processes and activities to support community entrepreneurship. The proposed framework highlighted in the research is a first step in formalising a way forward for entrepreneurship in the community.
Modeling and analysis of a process control system

This paper presents the modeling and analysis of a process control system. In particular, a landfill leachate treatment control system in its functional block form is first proposed from which a mathematical model for a subcomponent (cooling chamber) of the system is then developed. The proposed model is next analyzed to verify the viability of the sub-system.
Investigations of a Coherently Driven Semiconductor Optical Cavity QED System

Chip-based cavity quantum electrodynamics (QED) devices consisting of a self-assembled InAs quantum dot (QD) coupled to a high quality factor GaAs microdisk cavity are coherently probed through their optical channel using a fiber taper waveguide. We highlight one particularly important aspect of this all-fiber measurement setup, which is the accuracy to which the optical coupling level and optical losses are known relative to typical free-space excitation techniques. This allows for precise knowledge of the intracavity photon number and measurement of absolute transmitted and reflected signals. Resonant optical spectroscopy of the system under both weak and strong driving conditions are presented, which when compared with a quantum master equation model of the system allows for determination of the coherent coupling rate between QD exciton and optical cavity mode, the different levels of elastic and inelastic dephasing of the exciton state, and the position and orientation of the QD within the cavity. Pump-probe measurements are also performed in which a far off-resonant red-detuned control laser beam is introduced into the cavity. Rather than producing a measurable ac Stark shift in the exciton line of the QD, we find that this control beam induces a saturation of the resonant system response. The broad photoluminescence spectrum resulting from the presence of the control beam in the cavity points to sub-band-gap absorption in the semiconductor, and the resulting free-carrier generation, as the likely source of system saturation.
ACP Journal Club. Radical prostatectomy reduced mortality and disease progression over the long term more than watchful waiting in early prostate cancer.

Source Citation Bill-Axelson A, Holmberg L, Ruutu M, et al. Radical prostatectomy versus watchful waiting in early prostate cancer. N Engl J Med. 2011;364:1708-17. 21542742
The Intestinal Flora and Infant Botulism

The intestinal flora of experimental animals interferes with infection by species of Salmonella and Shigella. Protection against infection with these organisms appears to be related to high concentrations of volatile acids, low pH, and low oxidation-reduction potential of the intestinal contents of animals with an intact flora. There are no data to show that the flora influences colonization of the intestine with clostridial species, but indirect evidence suggests that the intestinal flora may be involved in this process. The impact of the intestinal flora on the ecology of the large intestine may be the most important determinant of resistance to infant botulism.
Overcoming shortcomings in schema-based software design systems

The paper describes a solution to the problem of acquiring reuseable design components for schema-based software design (SBD) systems. It also discusses some inherent shortcomings of the SBD approach that can be overcome by adopting a hybrid approach that incorporates the use of design cases. This discussion is made against the background of IDeA, an SBD system. >
Differential Pair Distribution Function Study of the Structure of Arsenate Adsorbed on Nanocrystalline γ-Alumina

Structural information is important for understanding surface adsorption mechanisms of contaminants on metal (hydr)oxides. In this work, a novel technique was employed to study the interfacial structure of arsenate oxyanions adsorbed on γ-alumina nanoparticles, namely, differential pair distribution function (d-PDF) analysis of synchrotron X-ray total scattering. The d-PDF is the difference of properly normalized PDFs obtained for samples with and without arsenate adsorbed, otherwise identically prepared. The real space pattern contains information on atomic pair correlations between adsorbed arsenate and the atoms on γ-alumina surface (Al, O, etc.). PDF results on the arsenate adsorption sample on γ-alumina prepared at 1 mM As concentration and pH 5 revealed two peaks at 1.66 A and 3.09 A, corresponding to As-O and As-Al atomic pair correlations. This observation is consistent with those measured by extended X-ray absorption fine structure (EXAFS) spectroscopy, which suggests a first shell of As-O at 1.69 ± 0.01 A with a coordination number of ~4 and a second shell of As-Al at ~3.13 ± 0.04 A with a coordination number of ~2. These results are in agreement with a bidentate binuclear coordination environment to the octahedral Al of γ-alumina as predicted by density functional theory (DFT) calculation.
Relating microwave backscatter azimuth modulation to surface properties of the Greenland ice sheet

Azimuth dependence of a normalized radar cross-section (σ°) over the Greenland ice sheet is modeled with a simple surface scattering model. The model assumes that azimuth anisotropy in surface roughness at scales of 3-300 m is the primary mechanism driving the modulation. To evaluate the contribution of azimuth anisotropy in surface roughness to the radar backscatter, the model is compared to models based on isotropic surface roughness. The models are inverted to estimate snow surface properties using σ° measurements from the C-band European Remote-sensing Satellite advanced microwave instrument in scatterometer mode. Results indicate that the largest mesoscale rms surface slopes are found in the lower portions of the dry snow zone. Estimates of the preferential direction in surface roughness are highly correlated with katabatic wind fields over Greenland, which is consistent with wind-formed sastrugi as the dominant mechanism causing azimuth modulation of σ°. The maximum improvement of the azimuth modulation surface model compared to its isotropic counterparts occurs in the lower regions of the dry snow zone where the azimuth variability of σ° is the largest. In regions with azimuth modulation over 1 dB, the mean root-mean-square error estimate of the azimuth-dependent surface scattering model is 0.46 dB compared with 0.70 dB for similar models using isotropic roughness.
Assessment of an instrumented reinforced-concrete bridge with fiber-reinforced-polymer strengthening

Field instrumentation is investigated on an in-service highway bridge over a 2-year period. Extrinsic Fabry-Perot interferometric EFPI strain sensors provide a permanent health-monitoring capability. The bridge is a reinforced-concrete RC structure that was repaired and strengthened using fiber-reinforced-polymer FRP wraps. A sensor net- work monitors the load-induced strain in the FRP reinforcement and the steel rebar. Colocated electrical resistance strain gauges and a finite element analysis are used for comparison. Both dynamic and static load characteristics are analyzed for a near-capacity truck. The fiber optic measurements are generally consistent with the comparison measure- ments and the analytical results; and they show no failure or degradation as opposed to the electrical resistance gauges. We demonstrate the implementation and the performance of in situ EFPI sensors in a long- term field environment. Embedded fiber optic sensors can provide the required information for the intelligent management of a transportation infrastructure. © 2007 Society of Photo-Optical Instrumentation Engineers.
A note on two-loop superloop

Abstract We explore the duality between supersymmetric Wilson loop on null polygonal contours in maximally supersymmetric Yang–Mills theory and next-to-maximal helicity violating (NMHV) scattering amplitudes. Earlier analyses demonstrated that the use of a dimensional regulator for ultraviolet divergences, induced due to presence of the cusps on the loop, yields anomalies that break both conformal symmetry and supersymmetry. At one-loop order, these are present only in Grassmann components localized in the vicinity of a single cusp and result in a universal function for any number of sites of the polygon that can be subtracted away in a systematic manner leaving a well-defined supersymmetric remainder dual to corresponding components of the superamplitude. The question remains though whether components which were free from the aforementioned supersymmetric anomaly at leading order of perturbation theory remain so once computed at higher orders. Presently we verify this fact by calculating a particular component of the null polygonal super Wilson loop at two loops restricting the contour kinematics to a two-dimensional subspace. This allows one to perform all computations in a concise analytical form and trace the pattern of cancellations between individual Feynman graphs in a transparent fashion. As a consequence of our consideration we obtain a dual conformally invariant result for the remainder function in agreement with one-loop NMHV amplitudes.