cssi/SciSciGPT-SciSciNet huggingface dataset:
Perforin Triggers a Plasma Membrane-Repair Response that Facilitates CTL Induction of Apoptosis

Perforin delivers granzymes to induce target-cell apoptosis. At high concentrations, perforin multimerizes in the plasma membrane to form pores. However, whether granzymes enter target cells via membrane pores is uncertain. Here we find that perforin at physiologically relevant concentrations and during cell-mediated lysis creates pores in the target-cell membrane, transiently allowing Ca(2+) and small dyes into the cell. The Ca(2+) flux triggers a wounded membrane-repair response in which internal vesicles, including lysosomes and endosomes, donate their membranes to reseal the damaged membrane. Perforin also triggers the rapid endocytosis of granzymes into large EEA-1-staining vesicles. The restoration of target-cell membrane integrity by triggering the repair response is necessary for target cells subjected to cytotoxic T lymphocyte attack to avoid necrosis and undergo the slower process of programmed cell death. Thus, the target cell actively participates in determining its own fate during cell-mediated death.
IMPAIRED OBJECT RECOGNITION FOLLOWING PROLONGED WITHDRAWAL FROM EXTENDED-ACCESS COCAINE SELF-ADMINISTRATION

Cocaine addicts have a number of cognitive deficits that persist following prolonged abstinence. These include impairments in executive functions dependent on the prefrontal cortex, as well as deficits on learning and memory tasks sensitive to hippocampal function. Recent preclinical studies using non-human animals have demonstrated that cocaine treatment can produce persistent deficits in executive functions, but there is relatively little evidence that treatment with cocaine produces persistent deficits in performance on hippocampal-dependent tasks. We recently demonstrated that extended (but not limited) access to self-administered cocaine is especially effective in producing persistent deficits on a test of cognitive vigilance, and therefore, we used this procedure to examine the effects of limited or extended access to cocaine self-administration on recognition memory performance, which is sensitive to hippocampal function. We found that extended access to cocaine produced deficits in recognition memory in rats that persisted for at least 2 weeks after the cessation of drug use. We conclude that the deficits in learning and memory observed in cocaine addicts may be at least in part due to repeated drug use, rather than just due to a pre-existing condition, and that in studying the neural basis of such deficits procedures involving extended access to self-administered cocaine may be especially useful.
Genome position and gene amplification.

Background: Amplifications, regions of focal high-level copy number change, lead to overexpression of oncogenes or drug resistance genes in tumors. Their presence is often associated with poor prognosis; however, the use of amplification as a mechanism for overexpression of a particular gene in tumors varies. To investigate the influence of genome position on propensity to amplify, we integrated a mutant form of the gene encoding dihydrofolate reductase into different positions in the human genome, challenged cells with methotrexate and then studied the genomic alterations arising in drug resistant cells. Results: We observed site-specific differences in methotrexate sensitivity, amplicon organization and amplification frequency. One site was uniquely associated with a significantly enhanced propensity to amplify and recurrent amplicon boundaries, possibly implicating a rare folate-sensitive fragile site in initiating amplification. Hierarchical clustering of gene expression patterns and subsequent gene enrichment analysis revealed two clusters differing significantly in expression of MYC target genes independent of integration site. Conclusion: These studies suggest that genome context together with the particular challenges to genome stability experienced during the progression to cancer contribute to the propensity to amplify a specific oncogene or drug resistance gene, whereas the overall functional response to drug (or other) challenge may be independent of the genomic location of an oncogene.
Do financial returns have finite or infinite variance? A paradox and an explanantion

One of the major points of contention in studying and modelling financial returns is whether or not the variance of the returns is finite or infinite (sometimes referred to as the Bachelier–Samuelson Gaussian world versus the Mandelbrot stable world). A different formulation of the question asks how heavy the tails of the financial returns are. The available empirical evidence can be, and has been, interpreted in more than one way. The apparent paradox, which has puzzled many a researcher, is that the tails appear to become less heavy for less frequent (e.g. monthly) returns than for more frequent (e.g. daily) returns, a phenomenon not easily explainable by the standard models. Inspired by the prelimit theorems of Klebanov, Rachev and Szekely (1999) and Klebanov, Rachev and Safarian (2000), we provide an explanation of this paradox. We show that, for financial returns, a natural family of models are those with tempered heavy tails. These models can generate observations that appear heavy tailed for a wide...
Antifacilitation and facilitation in the cardiac ganglion of the spiny lobsterPanulirus interruptus

Antifacilitation and facilitation of synaptic transmission between cell 6 and the large cells were studied in the spiny lobster cardiac ganglion. Two-impulse experiments invariably produced antifacilitation in the second large-cell PSP at all inter-pulse intervals (10 msec to 10 sec) (Fig. 2). When conditioning trains with 2–4 impulses preceded the test impulse, the test PSP was antifacilitated at intervals of less than 100 msec and usually facilitated at intervals greater than 100 msec (Fig. 3). At intervals shorter than 50 msec the test PSP amplitude was nearly independent of the number of conditioning impulses. At greater intervals, the test PSP amplitude was a linear function of the number of impulses in the conditioning train (Fig. 4 and 5). A model was constructed based on the assumption thatF (defined asVT/V0, whereV0 andVT are the control and test PSP amplitudes, respectively) is the sum of antifacilitation (F−) and facilitation (F+) (Fig. 9).F− depends only on the separation between the last conditioning impulse and the test impulse and is described by the equation:\(F^ - = 1.0 - A_1 e^{{{ - t} \mathord{\left/ {\vphantom {{ - t} {\tau _1 }}} \right. \kern-\nulldelimiterspace} {\tau _1 }}} - A_2 e^{{{ - t} \mathord{\left/ {\vphantom {{ - t} {\tau _2 }}} \right. \kern-\nulldelimiterspace} {\tau _2 }}} \), wheret is the conditioning-to-test interval in seconds,A1=0.26,A2=0.74,τ1=0.02 sec, andτ2=4.1 sec.F+ is described by the equationN C\((1 - e^{{{ - t} \mathord{\left/ {\vphantom {{ - t} {\tau _4 }}} \right. \kern-\nulldelimiterspace} {\tau _4 }}} )^2 \cdot e^{{{ - t} \mathord{\left/ {\vphantom {{ - t} {\tau _3 }}} \right. \kern-\nulldelimiterspace} {\tau _3 }}} \), whereN is the number of conditioning impulses,t is the interval between the end of the conditioning train and the test impulses,τ3=3.6 sec,τ4=0.08 sec, andC is a constant.
Open path water vapor measurements using a chirped pulse MIR QCL sensor system

An open path chirped pulse Quantum Cascade Laser system operating from 1900cm−1 to 1902 cm−1 has been developed for water vapor measurements. QCL retrieval accuracies are shown to be significantly smaller than FTIR retrievals.
Communication and memory requirements as the basis for mapping task and data parallel programs

For a wide variety of applications, both task and data parallelism must be exploited to achieve the best possible performance on a multicomputer. Recent research has underlined the importance of exploiting task and data parallelism in a single compiler framework, and such a compiler can map a single source program in many different ways onto a parallel machine. The tradeoffs between task and data parallelism are complex and depend on the characteristics of the program to be executed, most significantly the memory and communication requirements, and the performance parameters of the target parallel machine. In this paper, we present a framework to isolate and examine the specific characteristics of programs that determine the performance for different mappings. Our focus is on applications that process a stream of input, and whose computation structure is fairly static and predictable. We describe three such applications that were developed with our compiler: fast Fourier transforms, narrowband tracking radar, and multibaseline stereo. We examine the tradeoffs between various mappings for them and show how the framework is used to obtain efficient mappings.
A new depositional model for the classical turbidite locality at San Clemente State Beach, California

The Miocene turbidite system exposed in the beach cliffs at San Clemente State Beach, California, has been used by industry and academia alike as a field laboratory. It has been used as an analog for petroleum reservoirs in the Los Angeles Basin and other areas. We interpret the turbidite system at San Clemente State Beach to represent the fill of a single turbidite channel that aggraded subvertically. This interpretation is based on construction of a detailed photomosaic, mapping of three-dimensional facies distributions, measurement of representative sections, and collection of new paleocurrent data; we also extended this analysis to outcrops not previously described in the literature. The channel had a minimum width of 1 km and a paleotransport direction toward the northwest. Our new paleocurrent measurements indicate an average transport direction of 321 degrees for the channel deposits, approximately perpendicular to previously published paleocurrent data. Our paleocurrent data are in agreement with the trend of the channel as defined by facies mapping. The lateral and vertical facies changes along the sea cliffs at San Clemente are a result of interfingering between axial and marginal facies within a single turbidite channel. We interpret the turbidite channel to have been cut into a low-gradient continental slope (less than 1 degrees), rather than representing a channel on a submarine fan. We propose that the Gollum channel system is a modern analog of the turbidite system at San Clemente State Beach.
Overview of research activities at the NSF Center for Biophotonics Science and Technology (CBST)

We describe research highlights in three CBST theme areas: advanced microscopy, molecular and cellular biophotonics, and medical biophotonics. Highlights include coherent x-ray diffraction and image reconstruction, engineering of switchable phytochromes, and time-gated CARS imaging modalities.
DESIGNING RECYCLED HOT MIX ASPHALT MIXTURES USING SUPERPAVE TECHNOLOGY

Mix design procedures for recycled asphalt pavements require the selection of virgin asphalt binder or recycling agent. This research project was undertaken to develop a procedure for selecting the performance grade (PG) of virgin asphalt binder based on the Superpave PG grading system. Blending charts, similar to the viscosity blending charts, were constructed and evaluated based on test parameters obtained from the dynamic shear rheometer (DSR). The criteria for selection was based on Superpave performance grading (PG) specification. The criteria based on the fatigue parameter was determined to be too liberal and, therefore, was not recommended. An alternative criteria based on the high temperature stiffness was recommended.
A new genus and species of unusual tern (Aves: Laridae: Anoinae) from the Middle Miocene Calvert Formation of Virginia

Abstract Feducciavis loftini, new genus and species, is described from a single partial associated skeleton from the Middle Miocene Calvert Formation of Virginia. This bird was evidently most closely related to the noddy terns (Anoinae, Anous, Procelsterna). Compared with those genera, the tibiotarsus was much shorter and the ulna much longer in relation to the size of the humerus. The absolute size of the wing was considerably larger than in Anous stolidus, but the sternum was smaller. Aspects of the configuration of the quadrate and mandibular articulation are very distinct from any genus of modern gulls or terns, so that Feducciavis must have had singular feeding habits.
Steady state regulation of extramitochondrial Ca2+ by rat liver mitochondria. Effects of Mg2+ and ATP

An electrode-based system capable of monitoring ionized Ca2+ concentrations ([Ca2+]) < 1 microM was used to examine the regulation of extramitochondrial [Ca2+] by rat liver mitochondria. At the point of steady state balance between Ca2+ uptake and release, [Ca2+] ranged between 0.5 and 1.0 microM in a KCl/Hepes/succinate medium. When 1 mM Mg2+ was included in this basal medium, the range of steady state [Ca2+] values was 1-2 microM. Further additions (3 mM MgATP and 2 mM Pi) lowered extramitochondrial [Ca2+] to 0.4-0.8 microM. Thus under experimental conditions simulating the control of cytosolic [Ca2+], liver mitochondria buffered extramitochondrial [Ca2+] at constant values within the range of [Ca2+] estimated for liver cytosol; and cytosolic levels of Mg2+ and ATP significantly affected those steady state [Ca2+] values in directions consistent with previously reported effects of those modulators on mitochondrial Ca2+ uptake and release.
Dynamic contrast enhanced (DCE) magnetic resonance imaging (MRI) of atherosclerotic plaque angiogenesis

Atherosclerosis is a progressive systemic disease of the large arteries characterized by the formation of plaques in the vessel wall. Despite our knowledge of its pathogenesis, many vulnerable plaques still remain undiagnosed while in their asymptomatic phase and manifest for the first time with dramatic clinical events, such as stroke or myocardial infarction. In recent years, it is becoming clearer that sudden clinical events do not necessarily correlate with the degree of luminal obstruction caused by lesions, but rather with plaque composition. In particular, the degree of plaque inflammation is important in the pathogenesis of atherosclerosis and is considered a good marker of high-risk/vulnerable plaques. The presence of inflammatory infiltrate and plaque neovascularization are both histological hallmarks of atherosclerotic plaque inflammation. Therefore, plaque angiogenesis represents an attractive target to try and identify asymptomatic high-risk lesions. Dynamic contrast enhanced (DCE) magnetic resonance imaging (MRI) is a technique that has been used extensively in the past to study the vascularity of tumors and its changes following therapeutic intervention. Recently, delayed and dynamic contrast enhanced (CE) MRI have been proposed as non-invasive tools to study the extent of plaque neovascularization in animals and patients with atherosclerosis. In this review, we will provide a brief introduction on DCE-MRI acquisition and analysis techniques. We will follow this with a description of contrast enhanced MR methods for the detection and quantification of neovasculature in atherosclerosis, with an emphasis on DCE-MRI. Finally, we will examine the current limitations and challenges faced by DCE-MRI and briefly discuss its future applications in the context of atherosclerosis.
Biocompatible electrospun tactic poly(methyl methacrylate) blend fibers

Abstract Uniform and beads free fibers of pristine syndiotactic PMMA (s-PMMA), isotactic PMMA (i-PMMA), and their blends in the ratio of s:i = 3:1, 1:1 and 1:3 were successfully prepared using the electrospinning technique. The tactic PMMA blend fibers showed unique thermal stability and glass transition temperatures compared to their pristine counterparts. An interesting endotherm peak was observed for the s:i = 1:3 electrospun fibers, which might indicate a complex formation between the two tactic PMMAs. Systematic surface functionalities study by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) revealed the interactions between these two tactic PMMAs. Biocompatibility of tactic PMMA and their blend fibers was first time comparably investigated using HeLa as the model mammalian cell line; an intriguing observance was first revealed that the blend fibers showed better biocompatibility than both pristine ones, though the behind mechanism is not well understood yet.
The effects of ipsilateral, contralateral, and bilateral broadband noise on the mid-level hump in intensity discrimination.

Previous psychoacoustical and physiological studies indicate that the medial olivocochlear reflex (MOCR), a bilateral, sound-evoked reflex, may lead to improved sound intensity discrimination in background noise. The MOCR can decrease the range of basilar-membrane compression and can counteract effects of neural adaptation from background noise. However, the contribution of these processes to intensity discrimination is not well understood. This study examined the effect of ipsilateral, contralateral, and bilateral noise on the “mid-level hump.” The mid-level hump refers to intensity discrimination Weber fractions (WFs) measured for short-duration, high-frequency tones which are poorer at mid levels than at lower or higher levels. The mid-level hump WFs may reflect a limitation due to basilar-membrane compression, and thus may be decreased by the MOCR. The noise was either short (50 ms) or long (150 ms), with the long noise intended to elicit the sluggish MOCR. For a tone in quiet, mid-level hump WFs impr...
Ensuring an appropriate workforce in computing: keynote address

The past decade has witnessed a veritable roller-coaster ride in the computing workforce. During the late 90s, enrollments were booming in undergraduate computing programs as companies scrambled to find enough qualified individuals to fill jobs. IT was hot! With the dot.com crash in the early 2000s, this all changed. Suddenly, it looked like we had too many people for the jobs available, outsourcing and off-shoring of jobs was on everyone's minds, and prospective students and their parents worried about the wisdom of majoring in computing - would it be hard to find a job upon graduation? The shock of the dot.com crash has worn off, but what is the prospect for computing careers? What constitutes an appropriate workforce to meet the needs of employers? What should education be doing to prepare students more effectively for what they will find upon graduation? This presentation will address these questions, using the author's experiences as chair of the Computing Research Association's Taulbee Survey, as a member of the ACM Job Migration Task Force, and as a leader of the Computing Accreditation Commission of ABET
Recent Studies on the Molecular Defect in Apolipoprotein E Deficiency

Apolipoprotein (apo)E, a 34,000 molecular weight protein, functions in lipoprotein metabolism by modulating the hepatic catabolism of remnants of triglyceride rich lipoproteins (1,2). ApoE has been proposed to bind to a specific hepatic apoE receptor (3,4), and to the LDL receptor on peripheral cells and on the liver (3–6).
Marketing and Economic Development: the Saudi Arabian Experience

This paper argues that (a) marketing is indeed a catalyst of economic development in developing countries; (b) developing countries, in general, exhibit unique marketing, economic, and cultural characteristics that are different from those experienced in more developed Western countries; and (c) even though marketing plays an important role in the economic development of developing nations, modern marketing technology developed in the West and transferred to developing countries should be adapted and tailored to fit and match the specific needs of these developing countries. The case of the Saudi Arabian experience is used to illustrate the latter two themes.
Integrating interprofessional education into the curriculum: Challenges and solutions for a university without a medical center

The education of health care professionals has evolved from focusing on the individual practitioner's knowledge and skills to recognizing that high quality health care requires practitioners who are prepared to function in interprofessional teams. Higher education is heeding the call to prepare students to value teamwork and develop skills for working in interprofessional teams. While there is much written on implementing interprofessional education (IPE) in the practice setting and in larger institutions, there is little literature on implementing IPE within a university that is not affiliated with a medical school or medical center; which can be especially challenging. This article shares the many challenges to implementing IPE within this context and presents strategies one university used toward developing an integrated IPE program that is relevant to nine health-related disciplines.
Peer beliefs and smoking in adolescence: a longitudinal social network analysis.

ABSTRACTBackground: Peer smoking is one of the strongest predictors of adolescent cigarette use, but less is known about whether other peer characteristics also contribute to this behavior. Objectives: This study examined the links between adolescent cigarette use and peer beliefs about smoking. It tested whether peer beliefs about smoking are associated with changes in cigarette use, whether this association is a result of changes in individual beliefs about smoking, and how beliefs inform friendship choices. Methods: Analyses drew on data collected from 29 school-based networks, each measured at five occasions as students moved from 6th through 9th grade, as part of the study of the PROSPER partnership model. Longitudinal social network models provided estimates of friendship selection and behavior for an average of 6,200 students at each measurement point and more than 9,000 students overall. Results: Peer beliefs about smoking influenced cigarette use both directly and through their impact on individu...
Separate but equal? A system comparison study of MEDLINE's controlled vocabulary MeSH.

This study tested the effect of controlled vocabulary search feature implementation on two online systems. Specifically, the study examined retrieval rates using four unique controlled vocabulary search features (explode, major descriptor, descriptor, subheadings). Each search feature was applied to nine search queries obtained from a medical reference librarian. The same queries were searched in the complete MEDLINE file on the Dialog and Ovid systems. The unique records, i.e., those records retrieved in only one of the two systems, were identified and analyzed. Dialog produced equal or more records than Ovid in nearly 20% of the queries. The study demonstrated that users need to be aware of system-specific designs that may require differing input strategies across different systems for the same unique controlled vocabulary search features. The paper concludes by making recommendations and suggestions for future research.
Repetitive exercise dystonia: A difficult to treat hazard of runner and non-runner athletes

Abstract Introduction Runner's dystonia has previously been described in small series or case reports as a lower limb, task-specific dystonia. We have occasionally encountered this disorder and recognized the same phenomenon in non-runners regularly engaging in lower limb exercise. We wished to characterize the syndrome further, including outcomes, treatment, and the diagnostic usefulness of electrophysiology. Methods We conducted a retrospective review and follow-up survey of adults seen at Mayo Clinic (1996–2015) with task-specific dystonia arising after prolonged repetitive lower limb exercise. The findings were compared to all 21 previously reported cases of runner's dystonia. Results We identified 20 patients with this condition, 13 runners and seven non-runner athletes. Median age at dystonia onset was in mid-adulthood. Correct diagnosis was delayed by a median of 3.5 years in runners and 1.6 years in non-runners, by which time more than one-third of patients had undergone unsuccessful invasive procedures. Most patients had dystonia onset in the distal lower limb. Dystonia was task-specific with exercise at onset but progressed to affect walking in most. Sensory tricks were reported in some. Surface EMG was consistent with task-specific dystonia in nine patients. Botulinum toxin, levodopa, clonazepam, trihexyphenidyl, and physical therapy provided modest benefit to some, but all patients remained substantially symptomatic at last follow up. Conclusions Repetitive exercise dystonia is task-specific, confined to the lower limb and occasionally trunk musculature. It tends to be treatment-refractory and limits ability to exercise. Diagnosis is typically delayed, and unnecessary surgical procedures are common. Surface EMG may aid the diagnosis.
Why Ecclesial Structures at the Regional Level Matter: Communion as Mutual Inclusion:

In the one communion of all local churches, regional structures of authority are essential if the church is to live out its mission in each sociopolitical context. The article explores how structur...
The composition of glycosaminoglycans in developing rabbit lungs.

AbstractThe components of connective tissue of the lung, fundamentally important to pulmonary function, undergo changes during development of the lung. In an effort to understand connective tissue macromolecular changes, glycosaminoglycans (GAG) were isolated from the lungs of rabbits of various ages, newborn to 24 weeks old. The concentration of total GAG was 15% greater in the lungs of 1-week-old rabbits than in the lungs of newborns. The total GAG concentration gradually decreased between 1 week and 12 weeks of age from 4.2 mg/g dry-defatted tissue to 1.5 mg/g dry-defatted tissue, and then reached a plateau. The predominant GAG in the lungs of newborn and 1-week-old rabbits were hyaluronic acid and chondroitin 4-sulfate. These GAG decreased with age while other GAG, particularly chondroitin 6-sulfate, increased. Analyses of heparan sulfate fractions from lungs of rabbits of various ages showed a microheterogeneity in the molecule. Increase in sulfation of heparan sulfate was observed with age. The obse...
Indications for Computed Tomography in Patients with Minor Head Injury

Background Computed tomography (CT) is widely used as a screening test in patients with minor head injury, although the results are often normal. We performed a study to develop and validate a set of clinical criteria that could be used to identify patients with minor head injury who do not need to undergo CT. Methods In the first phase of the study, we recorded clinical findings in 520 consecutive patients with minor head injury who had a normal score on the Glasgow Coma Scale and normal findings on a brief neurologic examination; the patients then underwent CT. Using recursive partitioning, we derived a set of criteria to identify all patients who had abnormalities on CT scanning. In the second phase, the sensitivity and specificity of the criteria for predicting a positive scan were evaluated in a group of 909 patients. Results Of the 520 patients in the first phase, 36 (6.9 percent) had positive scans. All patients with positive CT scans had one or more of seven findings: headache, vomiting, an age ov...
Negative differential electrolyte resistance in a solid-state nanopore resulting from electroosmotic flow bistability

A solid-state nanopore separating two aqueous solutions containing different concentrations of KCl is demonstrated to exhibit negative differential resistance (NDR) when a constant pressure is applied across the nanopore. NDR refers to a decrease in electrical current when the voltage applied across the nanopore is increased. NDR results from the interdependence of solution flow (electroosmotic and pressure-engendered) with the distributions of K+ and Cl– within the nanopore. A switch from a high-conductivity state to a low-conductivity state occurs over a very narrow voltage window (<2 mV) that depends on the nanopore geometry, electrolyte concentration, and nanopore surface charge density. Finite element simulations based on a simultaneous solution of the Navier–Stokes, Poisson, and Nernst–Planck equations demonstrate that NDR results from a positive feedback mechanism between the ion distributions and electroosmotic flow, yielding a true bistability in fluid flow and electrical current at a critical ap...
Simplified Aerodynamics Models to Predict the Effects of Upstream Propellers on Wing Lift

In this paper we describe simple, two-dimensional aerodynamic models that incorporate the effects of the propeller installation angle to quickly estimate the lift augmentation from configurations in which multiple propellers are distributed upstream of a wing. The approach predicts variations in the apparent lift curve slope and zero-lift angle of attack of airfoils in the presence of propeller slipstreams of varying height. The angle of the slipstream relative to the airfoil and the height of the slipstream are both shown to have significant impacts on the lift augmentation. The methods presented in this paper are intentionally simple and can be used to help build a designer’s intuition about the effects of distributed leading edge propellers employed as high-lift devices.
A balanced and systematic leisure education service delivery model: connections to Eastern and Western perspectives

ABSTRACTThe purpose of this paper is to present a balanced and systematic leisure education service model using Eastern and Western perspectives. The term leisure education describes a multi-faceted, dynamic process that promotes exploration of perspectives and opportunities intended to develop an ethic of positivity and savouring that is conducive to flow, arousal, and leisure. Leisure education is designed to stimulate self-awareness, promote acquisition of leisure-related knowledge, and encourage skill development that enhances self-determination by meeting needs for autonomy, competence, and social connections, which are influenced by a variety of factors and people including family members, educators, leisure service providers, and neighbours. These leisure education services are applied across diverse audiences in various venues across the world designed to facilitate the interrelated positive experiences of leisure, happiness, and flourishing.
Comparison of a Buck Converter and a Series Capacitor Buck Converter for High-Frequency, High-Conversion-Ratio Voltage Regulators

This paper presents an analytical and experimental comparison of a two-phase buck converter and a two-phase, series capacitor buck converter. The limitations of a conventional buck converter in high-current (10 A or more), and high-frequency (HF, 3–30 MHz) point-of-load voltage regulators with large voltage conversion ratios (10-to-1) are highlighted. The series capacitor buck converter exhibits desirable characteristics at HF, including lower switching loss, less inductor current ripple, automatic phase current balancing, duty ratio extension, and soft charging of the energy transfer capacitor. Analysis of the topologies indicates that switching loss and inductor core loss can dominate at HF. Results from side-by-side 12 V input, 1.2 V output hardware prototypes demonstrate that the series capacitor buck converter has up to 12 percentage points higher efficiency at 3 MHz and reduces power loss by up to 33% at full load (10 A). Some guidelines for inductor selection are provided, and a switch stress comparison reveals that the maximum converter switch stress is reduced by 30%.
Aryl Hydrocarbon Receptor (AhR)/AhR Nuclear Translocator (ARNT) Activity Is Unaltered by Phosphorylation of a Periodicity/ARNT/Single-Minded (PAS)-Region Serine Residue

The aryl hydrocarbon nuclear translocator (ARNT) protein belongs to the family of basic helix-loop-helix (HLH)-periodicity/ARNT/single-minded [Per/ARNT/Sim (PAS)] transcription factors and regulates a range of cellular processes by either homodimerizing or heterodimerizing with other basic HLH-PAS proteins. To date, it has been shown that both the HLH and PAS domains are required for aryl hydrocarbon receptor (AhR) ARNT heterodimerization and that phosphorylation of ARNT is also required for this heterodimerization. Presently, regulation of ARNT with respect to phosphorylation is poorly understood. In an earlier study, murine ARNT was shown to be a phosphoprotein, to display charge heterogeneity, and to have a shift in its predominant isoforms after heterodimerization with the AhR. It was hypothesized that this shift may represent a change in ARNT phosphorylation status. Metabolic [(32)P]orthophosphate labeling of human ARNT-transfected COS-1 cells, in conjunction with phosphoamino acid analysis, Edman degradation, and phosphopeptide mapping, demonstrated that ARNT is predominantly phosphorylated on serine residues and that serine 348 (S348) in the PAS domain is phosphorylated. Alanine and glutamic acid substitutions were used to demonstrate that loss of phosphorylation at this site did not influence AhR-mediated xenobiotic response elements-driven or ARNT-mediated class B E-box-driven signaling. Additionally, the phosphorylation pattern of ARNT was unaltered after AhR heterodimerization. Although phosphorylation of S348 did not modulate AhR-ARNT or ARNT-ARNT signaling, phosphorylation of this PAS-region serine residue may be important in other ARNT-mediated gene expression systems.
[Psychosocial factors related to the practice of high risk sexual behavior among men who have sex with men: a review].

在美国等西方国家和某些亚洲国家如泰国，MSM是出现艾滋病流行与扩散最早和最主要的人群之一，已经成为HIV感染的重点人群之一，也是中国HIV／AIDS感染的高危人群和桥梁人群。MSM中普遍存在的多性伴和高危性行为是该人群感染HIV的主要原因。减少MSM高危性行为的频次可以减少HIV传播的发生。MSM中高HIV感染率已成为亟需解决的社会现实问题。社会心理学是建立在具体社会心理现象之上的理论，主要涉及社会认知、社会关系以及群体与群体过程三大领域。MSM作为弱势群体，由这一群体所衍生出的个体认知、社会认知、群际关系和社会关系等都属于社会心理学研究的范畴，从社会心理学角度对MSM高危性行为进行探索对了解MSM内群体以及与外群体的关系有着十分重要的意义。
Bacterial modification of taurocholate during enterohepatic recirculation in normal man and patients with small intestinal disease.

The bacterial metabolism of the primary bile acid, taurocholate, was studied during enterohepatic circulation in 18 patients with ileal disorders, 5 patients with disorders which involved the duodenojejunum primarily, and 4 student volunteers. Following intravenous injection of taurocholate-24-14C, the chemical composition of the total 14C radioactivity was determined in serial samples of duodenal fluid. Bacterial modification of taurocholate contributed materially to the maintenance of enterohepatic circulation of bile acids in normal subjects. The major transformation was deconjugation per se, resulting in the presence of reconjugated trihydroxy bile acids in the enterohepatic space. Deconjugation and 7-a-dehydroxylation, producing conjugates of deoxycholic acid, occurred to a lesser degree. The presence of intestinal pathology which caused “stasis” or obstruction appeared to favor the growth of organisms capable of deconjugation and 7-α-dehydroxylation, thereby resulting in a greater proportion of secondary dihydroxy bile acids present as conjugates of deoxycholic acid. The importance of an intact ileal transport mechanism in the maintenance of enterohepatic circulation of both primary and secondary bile acids is re-emphasized.
Stop! Drop. And Roll… Tackling Racism

Good elementary school teachers are a dying breed. We ask so much of them while simultaneously deciding to give them so little. With so many wide-ranging and varying job responsibilities, one can argue that these already full plates likely have little room for another job description: racism workshop facilitator. So how can overburdened and underpaid elementary school instructors take on this last role competently and capably? By remembering the elementary school adage frequently employed during fire drills: “Stop! Drop. And Roll....”
An Indefinitely Air-Stable σ-NiII Precatalyst for Quantitative Cross-Coupling of Unreactive Aryl Halides and Mesylates with Aryl Neopentylglycolboronates

Three classes of Ni precatalysts based on π-NiII, π-Ni0 and σ-NiII complexes have been elaborated and employed in different laboratories for the functionalization and cross-coupling of otherwise inert aryl C–O, C–Cl, and C–F electrophiles. Various Ni precatalysts, ligands, boron sources, and reaction conditions that were developed in various research groups, necessitated the selection of the most suitable conditions for desired cross-coupling partners. Here a universal, bench-stable, easily prepared NiIICl(1-naphthyl)(PCy3)2/PCy3 σ-complex, for efficient and quantitative cross-coupling of aryl chlorides, bromides, iodides, mesylates, and fluorides with aryl neopentylglycolboronates is reported. This precatalyst will most probably help to advance the applications of Ni catalysis in organic, supramolecular, and macromolecular synthesis and will provide an easier access to the selection of reaction conditions for various transformations.
Insufficient chunk concatenation may underlie changes in sleep-dependent consolidation of motor sequence learning in older adults

Sleep enhances motor sequence learning (MSL) in young adults by concatenating subsequences ("chunks") formed during skill acquisition. To examine whether this process is reduced in aging, we assessed performance changes on the MSL task following overnight sleep or daytime wake in healthy young and older adults. Young adult performance enhancement was correlated with nREM2 sleep, and facilitated by preferential improvement of slowest within-sequence transitions. This effect was markedly reduced in older adults, and accompanied by diminished sigma power density (12-15 Hz) during nREM2 sleep, suggesting that diminished chunk concatenation following sleep may underlie reduced consolidation of MSL in older adults.
Symbol and Substance in Local Government Workforce Development: First Source Hiring Programs

First Source programs intend to spur interviewing/hiring of hard-to-hire or disadvantaged individuals on local government contracts. Such programs are belief-based, rooted in values that must be translated into outcomes and subjected to diligent evaluation processes. The failure of values-based programs to achieve desired outcomes is an ethical consideration. This article views two First Source programs (in Washington, DC, and Providence, RI) through the lens of semiotics, asking what the program language says about symbol and meaning in public policy, and what these programs have led to in outcomes for workforce development. The programs show potential for community benefit, but ambiguity in detailing expectations and program processes may lead to underwhelming results, even though the passage or existence of the program might satisfy advocacy groups.
Is the chemoattractant chemerin a natural tumor-suppressive cytokine?

e13025 Background: Infiltration of specialized immune cells regulates the growth and survival of neoplasia. Chemerin, a recently described chemoattractant, attracts natural killer cells, macrophage...
Endogenous phosphorylation of the lipoprotein-associated coagulation inhibitor at serine-2.

Lipoprotein-associated coagulation inhibitor (LACI) inhibits activated Factor X (Xa) directly and, in an Xa-dependent fashion, inhibits Factor VIIa-tissue factor (TF), presumably by forming a quaternary Xa-LACI-VIIa-TF complex. LACI isolated from the conditioned media of HepG2 cells grown in the presence of [32P]orthophosphate was observed to be covalently phosphorylated. Dephosphorylation of 32P-LACI with phosphatase resulted in an almost complete removal of the radiolabel. Phosphoamino acid analysis of the purified 32P-LACI established that the phosphorylation occurred on (a) serine residue(s). At its N-terminus, LACI contains a cluster of acidic residues C-terminal to the serine-2 residue. Such a site is characteristic of the sites phosphorylated by casein kinase II (CKII) in protein substrates. Edman degradation of endogenously labelled 32P-LACI revealed that the serine-2 residue was a major site of phosphorylation. Phosphorylation of purified LACI by bovine CKII was observed to occur in vitro; amino acid sequence analysis demonstrated that CKII phosphorylated LACI at the serine-2 residue. Recombinant LACI expressed from mouse C127 fibroblasts transfected using a bovine-papilloma-virus expression vector was found to be endogenously phosphorylated. By using site-directed mutagenesis, an altered form of LACI was produced in which the serine-2 residue had been changed to alanine. This altered LACI, although expressed in similar quantity to the wild-type LACI, was not detectably phosphorylated. Using the altered LACI in functional studies demonstrated that a serine residue at position 2, and thus the phosphorylation of this site, was not essential for LACI‘s inhibition of Xa and VIIa-TF activities.
E-089 Iatrogenic Post-operative Carotid Artery Pseudoaneurysms, Diagnosis and Endovascular Management

Object Management of post-operative traumatic pseudoaneurysm of the external carotid and common carotid arteries has not been well characterized. Common presentation with early post-operative hemorrhages requires early diagnosis. We describe our experience with these lesions and review our diagnosis protocol, endovascular treatment and outcome. Methods This is a retrospective review of patients treated between 2005–2014. Early post operative hemorrhages required immediate packing by ENT surgeon, hemodynamic stabilization and diagnostic workup, usually by CTA and DSA evaluation. We utilized an angiographic protocol to characterize the lesion, the vessel involved and the collateral circulation patency. We utilized combination of coils and nBCA glue embolization, to obliterate the lesion and the vessel segment along the external carotid distribution. Post embolization specific Super-selective injections were utilized to verify complete occlusion. Immediate and early clinical and angiographic results were reviewed. Results We have treated 16 patients in this cohort. Thirteen lesions were associated with maxillofacial/oral surgeries and three were associated with tumor surgeries. Fifteen lesions were located in the ECA branches and one was located in the CCA. Fifteen patients presented with acute hemorrhage. We identified 13 pseudoaneurysms and three vessels interruptions. There were no procedural ruptures or complications. All aneurysms were completely obliterated, with early unpacking by ENT surgeon and hemodynamic stability, without any early re-hemorrhages. No early or delayed signs of ischemia were noted. Conclusions Carotid artery pseudoaneurysm, post maxillofacial/oral surgery can be treated early and effectively by endovascular procedures. High suspicion and early diagnosis associated with hemorrhages is crucial. Prompt imaging usually by CTA followed by selective cerebral angiography are highly effective. Utilization of coils and liquid embolic material can achieve immediate obliteration of the lesion and vessel segment. Selective post embolization studies of the collateral circulation are essential to confirm complete occlusion. Disclosures E. Nossek: None. K. Prajoy: None. J. Katz: None. A. Setton: None.
Asparagine-Linked Glycans of Cryptosporidium parvum Contain a Single Long Arm, Are Barely Processed in the Endoplasmic Reticulum (ER) or Golgi, and Show a Strong Bias for Sites with Threonine

Cryptosporidium parvum causes severe diarrhea in infants in developing countries and in immunosuppressed persons, including those with AIDS. We are interested in the Asn-linked glycans (N-glycans) of C. parvum, because (1) the N-glycan precursor is predicted to contain five mannose and two glucose residues on a single long arm versus nine mannose and three glucose residues on the three-armed structure common in host N-glycans, (2) C. parvum is a rare eukaryote that lacks the machinery for N-glycan-dependent quality control of protein folding in the lumen of the Endoplasmic Reticulum (ER), and (3) ER and Golgi mannosidases, as well as glycosyltransferases that build complex N-glycans, are absent from the predicted proteome. The C. parvum N-glycans reported here, which were determined using a combination of collision-induced dissociation and electronic excitation dissociation, contain a single, unprocessed mannose arm ± terminal glucose on the trimannosyl chitobiose core. Upon nanoUPLC-MS/MS separation and analysis of the C. parvum tryptic peptides, the total ion and extracted oxonium ion chromatograms delineated 32 peptides with occupied N-glycan sites; these were derived from 16 glycoproteins. Although the number of potential N-glycan sites with Thr (NxT) is only about twice that with Ser (NxS), almost 90% of the occupied N-glycan sites contain NxT. The two most abundant C. parvum proteins modified with N-glycans were an immunodominant antigen on the surface of sporozoites (gp900) and the possible oocyst wall protein 1 (POWP1). Seven other glycoproteins with N-glycans were unique to C. parvum; five shared common ancestry with other apicomplexans; two glycoproteins shared common ancestry with many organisms. In summary, C. parvum N-glycans are remarkable for the absence of ER and Golgi modification and for the strong bias toward occupancy of N-glycan motifs containing Thr.
Management of Uveitis and Scleritis in Necrobiotic Xanthogranuloma.

Abstract Necrobiotic xanthogranuloma (NXG) is a chronic, progressive non-Langerhans histiocytic granulomatous disease. While case reports describing periorbital involvement of NXG are frequent, only a few case reports describing ocular involvement, such as scleritis and uveitis, exist. Herein, we present a case presenting initially as bilateral anterior and posterior scleritis, as well as a chronic bilateral granulomatous panuveitis, and discuss the immunosuppressant options that should be considered for this disease with protean manifestations.
Oxidation Kinetics of Ferritic Alloys in High-Temperature Steam Environments

High-temperature isothermal steam oxidation kinetic parameters of several ferritic alloys were determined by thermogravimetric analysis. The oxidation kinetic constant (k) was measured as a function of temperature from 900°C to 1200°C. The results show a marked increase in oxidation resistance compared to reference Zircaloy-2, with kinetic constants 3–5 orders of magnitude lower across the experimental temperature range. The results of this investigation supplement previous findings on the properties of ferritic alloys for use as candidate cladding materials and extend kinetic parameter measurements to high-temperature steam environments suitable for assessing accident tolerance for light water reactor applications.
The blood-brain barrier internalises Cryptococcus neoformans via the EphA2-tyrosine kinase receptor

Cryptococcus neoformans is an opportunistic fungal pathogen that causes life-threatening meningitis most commonly in populations with impaired immunity. Here, we resolved the transcriptome of the human brain endothelium challenged with C. neoformans to establish whether C. neoformans invades the CNS by co-opting particular signalling pathways as a means to promote its own entry. Among the 5 major pathways targeted by C. neoformans, the EPH-EphrinA1 (EphA2) tyrosine kinase receptor-signalling pathway was examined further. Silencing the EphA2 receptor transcript in a human brain endothelial cell line or blocking EphA2 activity with an antibody or chemical inhibitor prevented transmigration of C. neoformans in an in vitro model of the blood-brain barrier (BBB). In contrast, treating brain endothelial cells with an EphA2 chemical agonist or an EphA2 ligand promoted greater migration of fungal cells across the BBB. C. neoformans activated the EPH-tyrosine kinase pathway through a CD44-dependent phosphorylation of EphA2, promoting clustering and internalisation of EphA2 receptors. Moreover, HEK293T cells expressing EphA2 revealed an association between EphA2 and C. neoformans that boosted internalisation of C. neoformans. Collectively, the results suggest that C. neoformans promotes EphA2 activity via CD44, and this in turn creates a permeable barrier that facilitates the migration of C. neoformans across the BBB.
Imaging of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC), the sixth most common cancer worldwide, is a frequent cause of diagnostic liver imaging [1]. It causes approximately 250,000 deaths per year worldwide [2]. Given the high prevalence of the disease, accurate screening and diagnosis of this tumor are critical for possible early intervention.