cssi/SciSciGPT-SciSciNet huggingface dataset:
Adverse Selection in the Labor Market and Slow Recoveries

In this paper I propose an equilibrium search and matching model with worker heterogeneity, asymmetric information, and endogenous separations, and argue that it can help our understanding of the U.S. labor market experience following the Great Recession of 2007–2009. Workers are heterogeneous in their ability, but a worker's ability becomes observable to a firm only after it hires the worker. This asymmetric information between former employers of a worker and his prospective employers has important implications for the response of the macroeconomy to shocks. I show that a deterioration in the distribution of ability in the pool of the unemployed leads firms to post fewer vacancies and to raise their hiring standards, thus lowering the job finding rates of all unemployed workers. The result is a slow recovery of employment and a shifting out of the Beveridge curve. I also theoretically characterize the impulse response of the economy to exogenous shocks to labor productivity and show that under plausible specifications of the general model the pool of the unemployed becomes more adversely selected in downturns. The model also provides an explanation for unemployment scarring: firms rationally discriminate against the long-term unemployed by demanding more unequivocally positive signals of their ability before hiring them. I further show that scarring is more severe for lower-ability workers and after deeper recessions. Finally, I discuss the relevant empirical literature and show that the evidence supports the predictions of the model.
Structured Random Matrices

Random matrix theory is a well-developed area of probability theory that has numerous connections with other areas of mathematics and its applications. Much of the literature in this area is concerned with matrices that possess many exact or approximate symmetries, such as matrices with i.i.d. entries, for which precise analytic results and limit theorems are available. Much less well understood are matrices that are endowed with an arbitrary structure, such as sparse Wigner matrices or matrices whose entries possess a given variance pattern. The challenge in investigating such structured random matrices is to understand how the given structure of the matrix is reflected in its spectral properties. This chapter reviews a number of recent results, methods, and open problems in this direction, with a particular emphasis on sharp spectral norm inequalities for Gaussian random matrices.
Human granulocytes generated in continuous bone marrow culture are physiologically normal

A long-term bone marrow culture system has been derived for maintenance and proliferation of human hemopoietic stem cells and granulocytes in vitro for up to 20 wk. The granulocytes generated in these cultures at 8 wk were comparable to fresh human peripheral blood granulocytes in physiologic properties, including phagocytosis, degranulation, respiratory burst, and bacterial killing: individual granulocytes generated up to 20 wk in several cultures demonstrated normal superoxide-generating capacity by NBT dye reduction slide test. Thus, human granulocytes generated in continuous marrow culture retain many biologic functions associated with bacterocidal capacity in vivo and indicate that this system should be of value in studies of disorders of granulocyte differentiation.
Science Signaling Podcast for 24 January 2017: Tissue-specific regulation of L-type calcium channels

This Podcast features an interview with Johannes Hell and Manuel Navedo, senior authors of two Research Articles that appear in the 24 January 2017 issue of Science Signaling, about tissue-specific regulation of the L-type calcium channel CaV1.2. This channel is present in many tissues, including the heart, vasculature, and brain, and allows calcium to flow into cells when it is activated. Signaling through the β-adrenergic receptor (βAR) stimulates CaV1.2 activity in heart cells and neurons to accelerate heart rate and increase neuronal excitability, respectively. Using mouse models, Qian et al found that βAR-mediated enhancement of CaV1.2 activity in the brain required phosphorylation of Ser1928, whereas βAR-mediated enhancement of CaV1.2 activity in the heart did not require phosphorylation of this residue. In a related study, Nystoriak et al demonstrated that phosphorylation of Ser1928 in arterial myocytes was required for vasoconstriction during acute hyperglycemia and in diabetic mice. These findings demonstrate tissue-specific differences in CaV1.2 regulation and suggest that it may be possible to design therapies to target this channel in specific tissues.Listen to Podcast.
High-Performance Charge Transport in Semiconducting Armchair Graphene Nanoribbons Grown Directly on Germanium

The growth of graphene on Ge(001) via chemical vapor deposition can be highly anisotropic, affording the facile synthesis of crystallographically controlled, narrow, long, oriented nanoribbons of graphene that are semiconducting, whereas unpatterned continuous graphene is semimetallic. This bottom-up growth overcomes long-standing challenges that have limited top-down ribbon fabrication (e.g., inadequate resolution and disordered edges) and yields ribbons with long segments of smooth armchair edges. The charge transport characteristics of sub-10 nm ribbons synthesized by this technique (which are expected to have band gaps sufficiently large for semiconductor electronics applications) have not yet been characterized. Here, we show that sub-10 nm nanoribbons grown on Ge(001) can simultaneously achieve a high on/off conductance ratio of 2 × 104 and a high on-state conductance of 5 μS in field-effect transistors, favorably comparing to or exceeding the performance of nanoribbons fabricated by other methods. ...
Phosphines as Silylium Ion Carriers for Controlled C–O Deoxygenation: Catalyst Speciation and Turnover Mechanisms

We report studies delineating the speciation, kinetics, and deoxygenation catalysis of phosphine-modified mixtures of B(C6F5)3 (BCF) and R3SiH. Combinations of BCF, a tertiary silane, and PAr3 generate the [H–B(C6F5)3–][R3Si–PAr3+] ion pair with conversions that depend on the silane and the phosphine. Smaller silanes enhance the ionization of the Si–H, as judged by heteronuclear NMR spectroscopy. Kinetic studies indicate that from BCF·PPh2(p-tol), formation of the borohydride/silyl phosphonium ion pair is α [Et3SiH]1[PPh2(p-tol)]0. DFT calculations confirmed the intermediacy of the weakly coordinated BCF···H–SiEt3 adduct en route to the silyl phosphonium. For the catalytic deoxygenation of anisole with Et3SiH, phosphine additives slow the reaction relative to phosphine-free conditions. In situ monitoring confirmed the presence of [H–B(C6F5)3–][Et3Si–PAr3+] at early times, but this slowly converts to [H–B(C6F5)3–][H3C–PAr3+], which is catalytically inactive. These data are reconciled by invoking a competit...
2 – The Onset of Genome Control in Embryogenesis

This chapter describes the onset of genome control in embryogenesis. The earliest stages of embryonic life also involve a certain amount of actual morphogenesis, in particular the construction of characteristic pregastrular structures, such as the hollow blastula of the echinoderm, or the structures demarcating the germinal layers from the nutrient syncytium in meroblastic eggs. Though specialized cellular structures, thus, exist even at these very early periods, pregastrular cells appear in general to be functionally nondifferentiated, at least in comparison to the situation following gastrulation when a variety of clearly specialized functional tissues has come into being. Differentiation in this discussion is defined as [A2]
Permissible Concentrations of Arsenic and Lead in Soils Based on Risk Assessment

Establishing permissible concentrations for As and Pb in soils is of practical importance because of toxicity of these metals, their widespread contamination, and limited resources available for remediation of contaminated soils. The USEPA pathway approach to risk assessment was used to assess an environmental hazard related to As and Pb in soils and to evaluate safe concentrations of these metals in contaminated soil. The results from large-scale field experiments with soil fly ash-biosolids blends were used as input data to analyze pathways of the most intense transfer of the contaminants to a target organism. A direct soil ingestion by children (the soil-human pathway) was considered the most important exposure route to soil As and Pb. A conservative risk analysis shows that As concentrations in soil can reach 40 μg g-1 without a hazard to exposed organisms. A Pb concentration in soil up to 300 μg g-1 does not cause an excessive intake of Pb by humans as evaluated by a direct soil ingestion exposure model.
Duals of tensor products

A number of tensor norms α for which the duality relation \((E\mathop \otimes \limits^\alpha F)' = E'\mathop \otimes \limits^{\alpha '} F')\)holds are described. This duality is used to investigate weak sequential completeness and reflexivity in tensor products.
Non-invasive rejuvenation/skin tightening: Light-Based devices

The popularity of non-invasive cosmetic improvement of the skin has continued to grow amongst patients and practitioners alike.
Is there congruence between the types of triggers that cause delight or disgust in cancer care

216Background: Much of patient satisfaction theory relates to meeting expectations and resolving needs, especially around doctor-patient interactions and the care environment. While there is substa...
Deep Learning vs. Bayesian Knowledge Tracing: Student Models for Interventions.

Bayesian Knowledge Tracing (BKT) is a commonly used approach for student modeling, and Long Short Term Memory (LSTM) is a versatile model that can be applied to a wide range of tasks, such as language translation. In this work, we directly compared three models: BKT, its variant Intervention-BKT (IBKT), and LSTM, on two types of student modeling tasks: post-test scores prediction and learning gains prediction. Additionally, while previous work on student learning has often used skill/knowledge components identified by domain experts, we incorporated an automatic skill discovery method (SK), which includes a nonparametric prior over the exercise-skill assignments, to all three models. Thus, we explored a total of six models: BKT, BKT+SK, IBKT, IBKT+SK, LSTM, and LSTM+SK. Two training datasets were employed, one was collected from a natural language physics intelligent tutoring system named Cordillera, and the other was from a standard probability intelligent tutoring system named Pyrenees. Overall, our results showed that BKT and BKT+SK outperformed the others on predicting post-test scores, whereas LSTM and LSTM+SK achieved the highest accuracy, F1-measure, and area under the ROC curve (AUC) on predicting learning gains. Furthermore, we demonstrated that by combining SK with the BKT model, BKT+SK could reliably predict post-test scores using only the earliest 50% of the entire training sequences. For learning gain early prediction, using the earliest 70% of the entire sequences, LSTM can deliver a comparable prediction as using the entire training sequences. The findings yield a learning environment that can foretell students’ performance and learning gains early, and can render adaptive pedagogical strategy accordingly.
A neutron-gamma pulse shape discrimination method based on pure and mixed sources

Abstract We present a novel trainable approach to distinguish neutrons from gammas using a particle detector . Traditionally, Pulse Shape Discrimination (PSD) methods for this problem utilize an ad-hoc computation of tail signal energy to perform the detection. Our first contribution is a rigorous analysis of the performance of this existing approach on gold standard Time of Flight (TOF) data. While this approach performs well for high energy pulses, its accuracy drops dramatically as the pulse energy decreases. Our second contribution is a novel data driven classifier that is trained from two readily available sources: one that emits gamma particles (Cs-137), and another that emits a mixture of gamma and neutron particles (Cf-252). We test our approach using TOF experiments and show a marked improvement in accuracy over the traditional method for low false positive rates and low energies.
Recombination Drives the Evolution of Mutational Robustness

Recombination can impose fitness costs as beneficial parental combinations of alleles are broken apart, a phenomenon known as recombination load. Computational models suggest that populations may evolve a reduced recombination load by reducing either the likelihood of recombination events (bring interacting loci in physical proximity) or the strength of interactions between loci (make loci more independent of one another). We review evidence for each of these possibilities and their consequences for the genotype-fitness relationship. In particular, we expect that reducing interaction strengths between loci will lead to genomes that are also robust to mutational perturbations, but reducing recombination rates alone will not. We note that both mechanisms most likely played a role in the evolution of extant populations, and that both can result in the frequently-observed pattern of physical linkage between interacting loci.
How to Fuse Expert Knowledge: Not Always “And” but a Fuzzy Combination of “And” and “Or”

In the non-fuzzy (e.g., interval) case, if two expert’s opinions are consistent, then, as the result of fusing the knowledge of these two experts, we take the intersection of the two sets (e.g., intervals) describing the expert’s opinions. In the experts are inconsistent, i.e., if the intersection is empty, then a reasonable idea is to assume that at least one of these experts is right, and thus, to take the union of the two corresponding sets. In practice, expert opinions are often imprecise; this imprecision can be naturally described in terms of fuzzy logic – a technique specifically designed to describe such imprecision. In the fuzzy case, expert opinions are not always absolutely consistent or absolutely inconsistent, they may be consistent to a certain degree. In this case, we show how the above natural idea of fusing expert opinions can be extended to the fuzzy case. As a result, we, in general, get not “and” (which would correspond to the intersection), not “or” (which would correspond to the union), but rather an appropriate fuzzy combination of “and”- and “or”-operations.
A discontinuous phase transition in the threshold-$\theta \geq 2$ contact process on random graphs

We study the discrete-time threshold-$\theta \geq 2$ contact process on random graphs of general degrees. For random graphs with a given degree distribution $\mu$, we show that if $\mu$ is lower bounded by $\theta+2$ and has finite $k$th moments for all $k>0$, then the discrete-time threshold-$\theta$ contact process on the random graph exhibits a discontinuous phase transition in the emergence of metastability, thus answering a question of Chatterjee and Durrett \cite{cd13}. To be specific, we establish that (i) for any large enough infection probability $p>p_1$, the process started from the all-infected state w.h.p. survives for $e^{\Theta(n)}$-time, maintaining a large density of infection; (ii) for any $p 0$, then it dies out in $O(\log n)$-time w.h.p.. We also explain some extensions to more general random graphs, including the Erd\H{o}s-R\'enyi graphs. Moreover, we prove that the threshold-$\theta$ contact process on a random $(\theta+1)$-regular graph dies out in time $n^{O(1)}$ w.h.p..
Deconstructing Poststroke Delirium in a Prospective Cohort of Patients With Intracerebral Hemorrhage.

OBJECTIVES Poststroke delirium may be underdiagnosed due to the challenges of disentangling delirium symptoms from underlying neurologic deficits. We aimed to determine the prevalence of individual delirium features and the frequency with which they could not be assessed in patients with intracerebral hemorrhage. DESIGN Prospective observational cohort study. SETTING Neurocritical Care and Stroke Units at a university hospital. PATIENTS Consecutive patients with intracerebral hemorrhage from February 2018 to May 2018. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS An attending neurointensivist performed 257 total daily assessments for delirium on 60 patients (mean age 68.0 [SD 18.4], 62% male, median intracerebral hemorrhage score 1.5 [interquartile range 1-2], delirium prevalence 57% [n = 34]). Each assessment included the Confusion Assessment Method for the ICU, Intensive Care Delirium Screening Checklist, a focused bedside cognitive examination, chart review, and nurse interview. We characterized individual symptom prevalence and established delirium diagnoses using Diagnostic and Statistical Manual of Mental Disorders, fifth edition criteria, then compared performance of the Confusion Assessment Method for the ICU and Intensive Care Delirium Screening Checklist against reference-standard expert diagnosis. Symptom fluctuation (61% of all assessments), psychomotor changes (46%), sleep-wake disturbances (46%), and impaired arousal (37%) had the highest prevalence and were never rated "unable to assess," while inattention (36%), disorientation (27%), and disorganized thinking (18%) were also common but were often rated 'unable to assess' (32%, 43%, and 44% of assessments, respectively), most frequently due to aphasia (32% of patients). Including nonverbal assessments of attention decreased the frequency of 'unable to assess' ratings to 11%. Since the Intensive Care Delirium Screening Checklist may be positive without the presence of symptoms that require verbal assessment, it was more accurate (sensitivity = 77%, specificity = 97%, area under the receiver operating characteristic curve, 0.87) than the Confusion Assessment Method for the ICU (sensitivity = 41%, specificity = 88%, area under the receiver operating characteristic curve, 0.64). CONCLUSIONS Delirium is common after intracerebral hemorrhage, but severe neurologic deficits may confound its assessment and lead to underdiagnosis. The Intensive Care Delirium Screening Checklist's inclusion of nonverbal features may make it more accurate than the Confusion Assessment Method for the ICU in patients with neurologic deficits, but novel tools designed for such patients may be warranted.
Human Body: A Wearable Product Designer’s Guide

This is a comprehensive look at the human body with respect to the form and function for wearable product design. The authors come from backgrounds in design (Karen L. LeBat, PhD) and medicine (Kar...
Paddle lead placement in the cervical spine region

Abstract A 52-year-old man is referred for placement of a cervical spine paddle lead after a successful trial by a pain physician in the community. He has had two anterior cervical discectomies with fusion in the past, at two separate levels (C45 and C56) at two separate times (3 years apart – first C56 and then C45). Although there had been improvement in his C6 distribution arm pain following the first surgery, he continued to have uncomfortable mechanical neck pain and then developed extension into his opposite shoulder over the subsequent year, eventually leading to the second surgery when the adjacent level C45 disk protrusion was noted. However, after this surgery, he had unrelenting neck pain despite what appeared to be a solid fusion construct and radicular-type pain on both sides in various distributions consistent with C5 and C6 and even C7 at times. After reviewing his films and noting no significant disk protrusion at previous levels or new levels, stable flexion-extension views showing a solid fusion, lack of notable benefit from gabapentin at 1800 mg/day and inability to tolerate pregabalin, and lack of success with epidural steroids and facet blocks and that he reported benefit from the trial stimulation of over 65%, a decision was made to proceed with paddle lead and implantable pulse generator (IPG) placement in the operating room on the elective schedule. Of note, he had also tried a round of chiropractic care as well as acupuncture treatments and had become accustomed to taking 5–10 mg of oxycodone every 6–8 hours, although he admitted this only improved his visual analog scale by perhaps one to two points from a typical 8/10 to 6/10 or 7/10 on most days.
Managers’ Perceptions of Crowding and Noise in New York State Parks

As visitation to New York State Parks continues to rise, it is important to evaluate potential crowding impacts on visitor experiences and the natural resources. This study examines park managers’ perceptions of crowding in New York State Parks. Using a semi-structured interview format, 20 managers were interviewed by telephone to identify their definition of crowding, the potential impacts that exist in their parks, the strategies currently in place to address potential impacts, and their perceptions of the effectiveness of these strategies. Most managers expressed concern about visitor accommodation, park facilities, and staffing resources. Additionally, impacts on the natural resources and visitor experiences were identified in several parks. The impacts identified were seemingly exacerbated by current state park agency staffing and budgetary trends, requiring managers to adapt and develop their own strategies to best combat some of the issues identified. Subscribe to JPRA
Mechanics of kerf patterns for creating freeform structures

A relief cutting method, or kerfing, is considered to create flexible freeform surfaces from relatively stiff and thick panels. The flexibility and moldability are achieved by introducing slender components within the panel, forming kerf patterns, and hence reducing the second moment and polar moment of an area of the solid panel. This paper presents a systematic study on the deformations of kerf unit-cells and of kerf panels. Two different kerf patterns, i.e., square and hexagon, with various cut densities are studied. The effects of different cutting density and kerf patterns on the stretching, bending, and twisting deformations are examined. Understanding the influence of kerf patterns and cut densities on various deformation mechanisms will guide the design of freeform complex shapes out of kerf panels. Experimental tests were performed on unit-cells under different boundary conditions, e.g., uniaxial and biaxial stretching and bending. The tests were also performed on kerf panels with different kerf patterns and varying cut densities. We used a nonlinear beam element in order to describe the deformations of the slender components within the kerf patterns. We compared the overall deformations in the kerf unit-cells and panels from the beam element model and experimental tests. Using the kerfing technique allows for generating flexible structures with complex geometries from mass-produced panels of standard shape and size. When using the kerfing method to achieve the desired surface topology, the stresses, strains, and displacements in the surface will depend on the kerf pattern, cut density, and constituent behavior.
The Δ Anion Gap/Δ Bicarbonate Ratio in Early Lactic Acidosis: Time for Another Delta?

Background The ratio of Δ anion gap and Δ bicarbonate (ΔAG/ΔHCO3) is used to detect coexisting acid-base disorders in patients with high anion gap metabolic acidosis. Classic teaching holds that, in lactic acidosis, the ΔAG/ΔHCO3 is 1:1 within the first few hours of onset and subsequently rises to 1.8:1. However, this classic 1:1 stoichiometry in early lactic acidosis was derived primarily from animal models and only limited human data. The objective of this study was to examine the ΔAG/ΔHCO3 within the first hours of the development of lactic acidosis. Methods Data were obtained prospectively from a convenience sample of adult (age >18 years) trauma-designated patients at a single level-1 trauma center. Venous samples, including a chemistry panel and serum lactate, were drawn before initiation of intravenous fluid resuscitation. Results A total of 108 patients were included. Of these, 63 patients had normal serum lactate levels (≤2.1 mmol/L) with a mean AG of 7.1 mEq/L, the value used to calculate subsequent ΔAG values. ΔAG/ΔHCO3 was calculated for 45 patients who had elevated serum lactate levels (>2.1 mmol/L). The mean ΔAG/ΔHCO3 for all patients with elevated serum lactate levels was 1.86 (SD, 1.40). Conclusions The mean ΔAG/ΔHCO3 was 1.86 within the first hours of the development of lactic acidosis due to hypovolemic shock, confirming a small prior human study. This contradicts the traditional belief that, in lactic acidosis, the ΔAG/ΔHCO3 is 1:1 within the first several hours. The classic 1:1 stoichiometry was determined on the basis of animal models in which lactic acid is infused into the extracellular space, facilitating extracellular buffering of protons by bicarbonate. In contrast, our results demonstrate a higher initial ΔAG/ΔHCO3 ratio in early endogenous lactic acidosis in humans. Our analysis indicates this is likely due to unmeasured anions contributing to an elevation in AG.
Ten Million Users and Ten Years Later: Python Tutor’s Design Guidelines for Building Scalable and Sustainable Research Software in Academia

Research software is often built as prototypes that never get widespread usage and are left unmaintained after a few papers get published. To counteract this trend, we propose a method for building research software with scale and sustainability in mind so that it can organically grow a large userbase and enable longer-term research. To illustrate this method, we present the design and implementation of Python Tutor (pythontutor.com), a code visualization tool that is, to our knowledge, one of the most widely-used pieces of research software developed within a university lab. Over the past decade, it has been used by over ten million people in over 180 countries. It has also contributed to 55 publications from 35 research groups in 13 countries. We distilled lessons from working on Python Tutor into three sets of design guidelines: 1) user experience design for scale and sustainability, 2) software architecture design for long-term sustainability, and 3) designing a sustainable software development workflow within academia. These guidelines can enable a student to create long-lasting software that reaches many users and facilitates research from many independent groups.
4. A Complete Li-Ion Battery Simulation Model (2014-01-1842)

Due to growing interest in hybrid and electric vehicles, li-ion battery modeling is receiving a lot of attention from designers and researchers. This paper presents a complete model for a li-ion battery pack. It starts from the Newman electrochemistry model to create the battery performance curves. Such information is then used for cell level battery equivalent circuit model (ECM) parameter identification. 28 cell ECMs are connected to create the module ECM. Four module ECMs are connected through a busbar model to create the pack ECM. The busbar model is a reduced order model (ROM) extracted from electromagnetic finite element analysis (FEA) results, taking into account the parasitic effects. Battery thermal performance is simulated first by computational fluid dynamics (CFD). Then, a thermal linear and time-invariant (LTI) ROM is created out of CFD solution. The thermal LTI ROM is then two-way coupled with the battery pack ECM to form a complete battery pack model. Thanks to the ROM technology, such a battery pack model can finish a complete charge discharge cycle within seconds of simulation time.
Thymosin α1 down-regulates the growth of human non-small cell lung cancer cells in vitro and in vivo

The effect of thymosin alpha 1 (THN alpha 1) and its NH2-terminal fragment (THN1-14) and COOH-terminal fragment (THN15-28) on non-small cell lung cancer (NSCLC) growth was evaluated. Using an anti-THN alpha 1 antibody, receptors were identified on NSCLC cells that were pretreated with 10(-6) M THN alpha 1. [3H]Arachidonic acid was readily taken up by NSCLC cells and THN alpha 1 significantly increased the rate of arachidonic acid release. THN1-15 slightly stimulated but THN15-28 and THN beta 4 did not alter arachidonic acid release from NCI-H1299 cells. In clonogenic growth assays in vitro, THN alpha 1 (10(-6) M) significantly decreased NSCLC colony number whereas THN1-14, THN15-28, and THN beta 4 were less potent. Using growth assays in vivo, THN alpha 1 (10 micrograms s.c./day) but not THN1-14, THN15-28, or THN beta 4 inhibited significantly NSCLC xenograft formation in nude mice. These data suggest that biologically active THN alpha 1 receptors are present on NSCLC cells and that native THN alpha 1 inhibits the growth of human NSCLC.
Cooperating Mobile Agents and Stabilization

In the execution of distributed algorithms on a network of processes, the actions of the individual processes are scheduled by their local schedulers or demons. The schedulers communicate with their immediate neighbors using shared registers or message passing. This paper examines an alternative approach to the design of distributed algorithms, where mobile agents are allowed to traverse a network, extract state information, and make appropriate modification of the local states to steer the system towards a global goal. The primary emphasis of this paper is system stabilization. Both single-agent and multi-agent protocols are examined, and the advantages and disadvantages of agent-based stabilization are discussed.
Biogeography for Bacteria

Multicellular animals and plants may face geographic barriers to migration and dispersal, enabling isolated populations to diverge into different species. Because of their small size and enormous abundance, unicellular organisms are thought to be able to disperse unhindered around the world. In his Perspective, Fenchel discusses studies published here ( Whitaker et al .) and elsewhere, which suggest that populations of thermophilic microorganisms have diverged over evolutionary time as a result of geographic isolation.
The Minimum Wage: Consequences for Prices and Quantities in Low-wage Labor Markets

Do moderate increases in the minimum wage reduce employment? If not, do they nevertheless raise wages? To examine these questions, we apply techniques of time-series analysis and systems estimation that are commonly used in macroeconomics and finance to five panels of data that contain between 11 and 34 low-wage industries. Our answers are "No" and "Yes" respectively. We find that increases in the federal minimum wage between 1947 and 1997 have raised average wages in many of these industries, especially the lowest wage ones. The effect on employment, however, is mixed and typically non-significant, even when average wages have risen.
Successful Lawyer Skills and Behaviors

The market for entry level legal talent circa 2013 is dysfunctional, as it is organized around stale and unreliable measures of academic ability. Both logic and experience, as well as a fair amount of social science, suggest that success as a lawyer depends upon a wide array of additional factors, such drive, personality, work-life experience, and the quality of one's formal education. Yet, legal employers continued over reliance on academic factors result in significant hiring mistakes. In turn, the low expectations of employers relieve law professors of the burden of having to improve the quality of legal education. If employers won't notice, why bother trying?This book chapter offers an explanation of how this strange state of affairs came to exist. It also draws upon a substantial amount of evidence to suggest that many law students have the potential to become great advocates, counselors and problem-solvers. They possess the requisite intelligence; and substantial subset also have the required motivation. All that is missing is excellent teaching, training, intensive practice, feedback and coaching. This is a tremendous opportunity for legal education and the legal profession.
Large-scale movements of large herbivores: livestock following changes in seasonal forage supply

Large-scale movements allow large herbivores to cope with changes in seasonal forage supply. Pastoralists use mobility to convert low-value ephemeral forage into high-value livestock. Transhumant pastoralists may move livestock less than ten to hundreds of kilometres. In semi-arid tropical sites, water and forage shortages in the dry season cause pastoral livestock to move to water or key resource areas. In temperate summers, livestock may be moved to higher-elevation snow-free meadows. In winters, animals may be moved lower to warmer sites, or to mountain valleys protected from steppe winds. Despite the recognised value of mobility, pastoral mobility is being reduced around the world. Changes in the mobility of three pastoral groups are reviewed, the Aymara of the South-American highlands, Mongolians, and the Maasai of Kenya and Tanzania, for which quantitative results are given. The Maasai of Kajiado District, Kenya are subdividing some group ranches into individually owned parcels. In subdivided Osilalei Group Ranch, herders moved an average of 5.6 km per day, whereas in undivided northern Imbirikani, herders moved 12.5 km per day. Residents of northern Imbirikani accessed more green vegetation the more they moved, whereas those in subdivided southern Imbirikani did not. Maasai selected areas with more heterogeneous vegetation during the dry season than found at their permanent households. In modelling, subdividing to 100-ha parcels allowed Eselengei Group Ranch to support 25% fewer livestock by mass, even though the area remained the same. For any pastoralist, the costs of mobility must be weighed against benefits, but pastoralists have demonstrated flexibility in their mobility, if constraints such as human population growth and limitations in land access are not too great. We show that pastoralists have successfully evolved methods of herding livestock to access adequate forage in areas of variable climate
Abstract 568: ApoE-/- Mice Lacking Hemopexin Develop Aggravated Atherosclerosis via Mechanisms That Include Altered High Density Lipoprotein Inflammatory Properties and Macrophage Function

Introduction: The etiology of atherosclerosis is multi-faceted. Atherosclerotic plaques are characterized by the accumulation of lipid-laden macrophages, reactive oxygen species (ROS) and pro-inflammatory lipoproteins. Recent studies suggest that the anti- or pro-inflammatory nature of high density lipoprotein (HDL) may be a more sensitive indicator of atherosclerosis than HDL-cholesterol (HDL-C) levels alone. Our laboratory previously reported that hemopexin (Hx) is significantly increased and associated with pro-inflammatory HDL under atherogenic conditions. Hx is a heme scavenging protein which together with macrophages, plays a role in mitigating heme and ROS mediated oxidative damage. However, the role of Hx in atherosclerosis is not known. Hypothesis: We hypothesized that absence of Hx plays an important role in the accumulation of pro-inflammatory HDL, macrophage function, and the development of atherosclerosis. Methods: We crossed Hx-/- mice onto the apoE-/- background (HxE-/- mice). Chow diet fed...
Cognitive remediation strategies : an adjunct to the psychotherapy of adults with attention-deficit hyperactivity disorder.

Evidence continues to emerge that childhood symptoms of attention-deficit hyperactivity disorder (ADHD) persist into adulthood. These symptoms include motoric hyperactivity, restlessness, attention deficits, poor organizational skills, impulsivity, and memory impairment. Poor academic and work performance, frustration, humiliation, and shame are also components of adult ADHD. Psychotherapists are challenged to understand the meaning of the disorder and its ramifications in all aspects of life. An active multimodal approach, including somatic treatment and psychotherapy, is needed. In addition, cognitive remediation strategies to enhance attention, organization, memory, and problem-solving skills are an important adjunct to treatment. These strategies serve as psychological tools to circumvent deficits.
Composition and physical properties of starch in microgravity-grown plants

The effect of spaceflight on starch development in soybean (Glycine max L., BRIC-03) and potato (Solanum tuberosum, Astroculture-05) was compared with ground controls by biophysical and biochemical measurements. Starch grains from plants from both flights were on average 20-50% smaller in diameter than ground controls. The ratio delta X/delta rho (delta X --difference of magnetic susceptibilities, delta rho--difference of densities between starch and water) of starch grains was ca. 15% and 4% higher for space-grown soybean cotyledons and potato tubers, respectively, than in corresponding ground controls. Since the densities of particles were similar for all samples (1.36 to 1.38 g/cm3), the observed difference in delta X/delta rho was due to different magnetic susceptibilities and indicates modified composition of starch grains. In starch preparations from soybean cotyledons (BRIC-03) subjected to controlled enzymatic degradation with alpha-amylase for 24 hours, 77 +/- 6% of the starch from the flight cotyledons was degraded compared to 58 +/- 12% in ground controls. The amylose content in starch was also higher in space-grown tissues. The good correlation between the amylose content and delta X/delta rho suggests, that the magnetic susceptibility of starch grains is related to their amylose content. Since the seedlings from the BRIC-03 experiment showed elevated post-flight ethylene levels, material from another flight experiment (GENEX) which had normal levels of ethylene was examined and showed no difference to ground controls in size distribution, density, delta X/delta rho and amylose content. Therefore the role of ethylene appears to be more important for changes in starch metabolism than microgravity. c2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved.
Ultraviolet absorption spectra of peptides. IV. Alanine residue.

Spectra in the ultraviolet region from about 200 to 240 mμ are presented for the different ionic species of a series of alanine peptides containing from two to six l-alanine residues. They are very similar in general appearance and additivity characteristics to the spectra of the corresponding glycine peptides. However, they are somewhat elevated, particularly at longer wavelengths. Substitution of a d-alanine residue for the middle l-alanine residue in the tripeptide does not change the spectra appreciably. Spectra are also presented for acetyl-dl-alanylglycine, glycyl-l-alanylglycine, glycyl-l-alanyl-l-alanine, and dl-alanine anhydride. The idea of the additivity of residue spectra applies fairly well to the observed spectra of all but the last of these compounds.
Mechanisms by which AC leakage currents cause complete hemodynamic collapse without inducing fibrillation.

AC-Induced Non-VF Collapse.Introduction: The first study of weak alternating current (AC) stimulation in closed chest humans showed that complete hemodynamic collapse can occur below the threshold for inducing ventricular fibrillation (VF), a heretofore unknown danger to patients. This article, and the accompanying simulation article, explore the mechanisms responsible for the collapse. Methods and Results: A quadripolar pacing catheter was placed in the right ventricle (RV) of six dogs. The tip of the catheter (17 mm2) carried 5 seconds of AC stimulation ranging from 10 to 160 Hz and 10 to 1,000 μA. The lead II body surface ECG, femoral artery pressure, and a bipole from the proximal pair of electrodes on the RV catheter were recorded 2 seconds before, during, and 2 seconds after stimulation. Based on the blood pressure, every episode was categorized as VF, COLLAPSE without VF, extrasystolic without COLLAPSE (EFFECT), or having caused no effect (NSR). The electrical activation interval (interspike interval [ISI]) from the RV bipole was compared with the mechanical activation interval, determined from M-mode ultrasound. COLLAPSE is associated with a short ISI (NSR = 408 ± 110 msec; EFFECT = 305 ± 113 msec; COLLAPSE = 179 ± 25 msec; P < 0.001) with a high degree of regularity (P < 0.001): coefficient of variation of ISI for COLLAPSE (0.038 ± 0.069) versus VF (0.389 ± 0.222), EFFECT (0.420 ± 0.241), and NSR (0.016 ± 0.048). Electrical activation and mechanical activation rates occurred at integer multiples of the AC stimulation period. Conclusion: COLLAPSE (86 ± 37 μA; minimum 50 μ A in two animals) occurs below the VF threshold (108 ± 28 μA) by causing rapid, regular excitation.
Development of a two-dimensional focusing faceted x-ray analyzer

ABSTRACT                     !   "             #    $ %   ! &'()         * $     +   ,   +!  +#    Keywords: -     *    1. INTRODUCTION       .     / " " + 10  01 2  $    3    3   +  + 4         + 1 5       +  $ $      6 /  "   * 2,3    /       4 5           -     *        $        $ + *     $  + *  $ 7            5 *          5                5,6  $        $      8        
American capitalist experiments in revolutionary-era Russia

Abstract In this paper I document one particular moment in the making of the United States’ hegemony by tracking the lives of two American businessmen in revolutionary-era Russia. Drawing on a diverse array of archival sources (letters, diaries, photo albums, memoirs), and focusing on the training, practices, encounters, degrees of embeddedness and personal situations of two men (Walter Dixon and Boies Hart), I suggest that revolutionary-era Russia served in some ways as a proving ground for testing the effectiveness of American corporate structure, geoeconomic imaginations, and commercial practices. Although these two businessmen were minor figures in the much larger story of the making of American hegemony, their experiences in revolutionary Russia – experiences that were mediated through geoeconomic imaginations, local knowledge of place, degrees of embeddedness, personal encounters with people, places and networks, early twentieth-century ideals of manliness, and feelings of trust, anxiety, and fear – bring to life the uneven, chaotic, risky, and at times unsuccessful and violent ways that American capital began to move through difference in space.
Effect of pore geometry and interfacial tension on water-oil displacement efficiency in oil-wet microfluidic porous media analogs

Using oil-wet polydimethylsiloxane (PDMS) microfluidic porous media analogs, we studied the effect of pore geometry and interfacial tension on water-oil displacement efficiency driven by a constant pressure gradient. This situation is relevant to the drainage of oil from a bypassed oil-wet zone during water flooding in a heterogeneous formation. The porosity and permeability of analogs are 0.19 and 0.133–0.268 × 10−12 m2, respectively; each analog is 30 mm in length and 3 mm in width, with the longer dimension aligned with the flow direction. The pore geometries include three random networks based on Voronoi diagrams and eight periodic networks of triangles, squares, diamonds, and hexagons. We found that among random networks both pore width distribution and vugs (large cavities) decreased the displacement efficiency, among the periodic networks the displacement efficiency decreased with increasing coordination number, and the random network with uniform microfluidic channel width was similar to the hexagon network in the displacement efficiency. When vugs were present, displacement was controlled by the sequence of vug-filling and the structure of inter-vug texture was less relevant. Surfactant (0.5 wt. % ethoxylated alcohol) increased the displacement efficiency in all geometries by increasing the capillary number and suppressing the capillary instability.
Changes in QT dispersion after thrombolysis for stroke

Abstract Background QT dispersion (QTD) reflects heterogeneity of myocardial repolarization, which is modulated by the central nervous system. Although largely studied in patients with cardiovascular disease, QTD is increased in acute stroke and this finding is an independent predictor of functional outcome and mortality following acute neurological events. Hypothesis The hypothesis of this study was to determine whether changes in QTD in patients presenting with ischemic stroke parallel changes in neurologic function. Methods We retrospectively studied 30 consecutive patients (76±9 years, 50% male) who received thrombolytic therapy for acute ischemic stroke between September 1996 and August 2002, and had multiple electrocardiograms (ECGs). QTD was calculated from the admission ECG and the last available ECG (median 3 days) during hospital admission as the absolute difference between the maximum and minimum QT intervals in at least 11 of 12 leads. The National Institute of Health Stroke Scale (NIHSS) was used to assess neurological status on admission and discharge. ΔQTD was calculated as the absolute difference between QTD measured on admission and on the last available ECG. Absolute changes in heart rate corrected QTD (ΔQTDc) and NIHSS scores (ΔNIHSS) were also calculated. Results ΔQTD was significantly higher in the 27% of patients who died as compared to the survivors (44±26 ms vs. −2±21 ms, p r =0.57, p r =0.60, p Conclusion ΔQTD are associated with changes in neurological function in patients treated with thrombolytic therapy for acute ischemic stroke.
Molecular assembly of multilayer enzyme on fiber optic surface: toward the development of chemiluminescence-based fiber optic biosensors

We report here on a technique to immobilize a multilayer enzyme assembly on an optic fiber surface. A multilayer of an enzyme, alkaline phosphatase, was successfully immobilized on an optical fiber surface. Chemiluminescence, ellipsometry, and surface plasmon resonance were used to characterize the structure and activity of the assembly. A chemiluminescence-based fiber optic biosensor utilizing this immobilization technique has been developed for the detection of organophosphorous-based pesticides. Detection of pesticide at sub-ppm level has been achieved for paraoxon.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Dynamic state feedback control of two cooperative manipulators

Abstract Dynamic coordinated control of two robot manipulators that rigidly grasp a common object is studied. A dynamic coordinated control model for the two manipulators is derived that is suitable for system analysis and design in state space. The model takes into account kinematic and dynamic constraints between the two manipulators, and is explicitly described by non-linear state equtions and non-linear output equations in the state space. Since coordinated control requires the control of forces applied to the object by manipulators, the output equations include both position components and force components. While robotic systems with position outputs can be linearized using a static state feedback, systems with force outputs, such as the present two robot system, require a dynamic non-linear state feedback for exact linearization. By using dynamic non-linear feedback, coordinated control of two robotic manipulators is converted into a control problem of linear systems.