cssi/SciSciGPT-SciSciNet huggingface dataset:
A higher altitude is an independent risk factor for venous thromboembolisms following total shoulder arthroplasty.

Abstract Introduction High altitudes lead to physiological changes that may predispose to venous thromboembolisms (VTE) including deep vein thrombosis (DVT) and pulmonary embolism (PE). No prior study has evaluated if there is also a higher risk of VTEs after total shoulder arthroplasties (TSAs) performed at higher elevations compared to lower elevations. The purpose of this study was to identify if undergoing TSA at a higher altitude center (>4000 feet above sea level) is an independent risk factor for a postoperative VTE. Methods A retrospective review was performed from 2005 to 2014 using the Medicare Standard Analytical Files of the Pearl Diver database (Pearl Diver Technologies, West Conshohocken, PA, USA). The inclusion criteria for the study group consisted of all patients in the database undergoing primary TSAs at an altitude above 4000 feet. Patients were queried using the International Classification of Disease 9th revision codes (ICD-9). All patients undergoing primary TSA were queried using ICD-9 procedure code 81.80. Patients were filtered using the zip codes of the hospitals where the procedure occurred and were separated into high (>4,000 ft) and low ( Results In the first 30 postoperative days, patients undergoing TSA at a higher altitude experienced a significantly higher rate of PEs (odds ratio [OR], 39.5; P = Conclusion TSAs performed at higher altitudes (>4000 feet) have a higher rate of acute postoperative PEs in the first 30 days and 90 days postoperatively when compared to matched patients receiving the same surgery at a lower altitude (
Logical scalability and efficiency of relational learning algorithms

Relational learning algorithms learn the definition of a new relation in terms of existing relations in the database. The same database may be represented under different schemas for various reasons, such as efficiency, data quality, and usability. Unfortunately, the output of current relational learning algorithms tends to vary quite substantially over the choice of schema, both in terms of learning accuracy and efficiency. We introduce the property of schema independence of relational learning algorithms, and study both the theoretical and empirical dependence of existing algorithms on the common class of (de) composition schema transformations. We show theoretically and empirically that current relational learning algorithms are generally not schema independent. We propose Castor, a relational learning algorithm that achieves schema independence.
Bandwidth Enhanced Low-VHF Communications with a Miniature Non-Foster Antenna

We investigate low-frequency communications with a highly miniature bandwidth-enhanced antenna. To achieve improved bandwidth while maintaining a small form factor, a non-Foster matching technique is applied to a λ/50 low-Vhfantenna. The practical use of existing non-Foster matched antennas has been hindered due to their sensitivity to small system induced variations as well as nearby scatterers. We carry out software defined radio based wireless data transmission experiments with varying data rates to investigate the performance of our proposed antenna for practical applications in indoor environments. Experimental results show the non-Foster matched antenna enables transmitting data with rates three times higher than the same antenna matched with passive elements. We present communication quality measures by transmitting several packets and computing the signal-to-interference-plus-noise-ratio (SINR), the symbol error rate, and cross-correlation between transmitted and received pulses.
CT detection of primary and metastatic ileal carcinoid tumor: rates of missed findings and associated delay in clinical diagnosis.

To determine the rate of missed CT findings of ileal carcinoid tumor prior to pathologic diagnosis and the resultant diagnostic delay. Initially, 74 patients with abdominal and pelvic CT prior to pathologically-proven diagnosis of ileal carcinoid were identified. Patients were excluded when the original CT study (n = 6) or report (n = 4) was not available, resulting in a final cohort of 64 patients (mean age, 58.3 years; 29 M/35F); 27 (42%) patients had more than one abdominal CT prior to diagnosis. All available CT studies prior to diagnosis were retrospectively reviewed for the presence of the primary ileal tumor and metastatic disease (mesenteric and hepatic). Primary ileal tumors were prospectively missed on at least one CT scan in 64% (32/50) of patients with retrospectively identifiable disease. CT findings of mesenteric spread were missed at least once in 46% (25/54) of cases where present in retrospect. By the final pre-operative CT, hepatic metastases and bowel wall thickening were present in 55% (35/64) and 52% (33/64) of cases, respectively. In patients with missed ileal and/or mesenteric findings resulting in diagnostic delay, mean delay was 40 months (range 4–98 months). Initial presentation of ileal carcinoid tumor, even with mesenteric involvement, is often missed prospectively at abdominal CT, leading to delay in diagnosis until bowel or mesenteric findings become more obvious, or hepatic metastatic disease manifests. Radiologists should make a concerted effort to evaluate the bowel and mesentery in patients with long-standing vague abdominal symptoms.
Reoperation rates for pelvic organ prolapse repairs with biologic and synthetic grafts in a large population-based cohort

As the long-term complications of synthetic mesh become increasingly apparent, re-evaluation of alternative graft options for pelvic organ prolapse (POP) repairs is critical. We sought to compare the long-term reoperation rates of biologic and synthetic grafts in POP repair. Using the California Office of Statewide Health Planning and Development database, we identified all women who underwent index inpatient POP repair with either a synthetic or biologic graft between 2005 and 2011 in the state of California. ICD-9 and CPT codes were used to identify subsequent surgeries in these patients for either recurrent POP or a graft complication. A total of 14,192 women underwent POP repair with a biologic (14%) or synthetic graft (86%) during the study period. Women with biologic grafts had increased rates of surgery for recurrent pelvic organ prolapse (3.6% vs 2.5%, p = 0.01), whereas women with synthetic grafts had higher rates of repeat surgery for a graft complication (3.0 vs 2.0%, p = 0.02). There were no significant differences between the overall risk of repeat surgery between the groups (5.7% vs 5.6%, p = 0.79). These effects persisted in multivariate modeling. We demonstrate in a large population-based cohort that biologic grafts are associated with an increased rate of repeat surgery for POP recurrence whereas synthetic mesh is associated with an increased rate of repeat surgery for a graft complication. These competing risks result in an equivalent overall any-cause repeat surgery rate between the groups. These data suggest that neither type of graft should be excluded from use and encourage a personalized risk assessment.
Toward a Better Understanding of In-Vehicle Auditory Warnings and Background Noise:

ObjectiveThe effectiveness of three types of in-vehicle warnings was assessed in a driving simulator across different noise conditions.BackgroundAlthough there has been much research comparing diff...
Shock in the Cardiac Patient

Shock is defined as an imbalance between oxygen delivery (DO2) and oxygen consumption (VO2). Oxygen demand greater than oxygen delivery leads to a severe decrease in tissue oxygenation, nutrient delivery, and eventually cell death. Shock can damage all tissues and quickly progress to multiorgan failure. This is why early identification and treatment of shock is critical to prevent irreversible cell death. This chapter provides an overview of the diagnosis and management of this complex entity.
Association of Bolster Duration With Uptake Rates of Fibula Donor Site Skin Grafts.

Importance The fibula free flap donor site is associated with both short-term and long-term morbidity. Split-thickness skin graft (STSG) loss can lead to long delays in donor site healing and is associated with significant adverse sequelae. Patients may experience initial good STSG uptake after bolster removal but may have subsequent partial or total loss related to contact pressure or shearing. Objective To determine if increased duration of bolster use is associated with increased STSG uptake rates following fibula free flap reconstruction. Design, Setting, and Participants This retrospective cohort study included patients 18 years and older undergoing fibula free flap reconstruction following head and neck extirpative surgery at a tertiary care academic medical center from May 2013 to March 2019. The donor sites were photographed 4 weeks postoperatively, and areas of graft uptake were measured using image processing software. The baseline demographic, comorbidity, and operative characteristics were also collected. Interventions A fine mesh gauze with 3% bismuth tribromophenate and petrolatum blend bolster was sutured over leg STSGs placed on fibula free flap donor sites intraoperatively, and the ankle and lower leg were immobilized for 5 days in a plaster splint. Bolsters were either removed on postoperative day 5 or 14. Thereafter, the STSGs were covered with a petroleum and bismuth gauze and a cotton dressing. Main Outcomes and Measures Rates of donor site infection and STSG percentage uptake at 4 weeks. Results Of the 42 included patients, 31 (74%) were male, and the mean (SD) age was 62.1 (13.1) years. A total of 20 patients were included in the 5-day group, and 22 were included in the 14-day group. The 14-day bolster group had a higher mean percentage skin graft uptake rate compared with the 5-day bolster duration group (77.5% vs 59.9%), with an effect size of −0.632 (95% CI, −1.260 to −0.004). Patients with Adult Comorbidity Evalution-27 scores of 3 had poorer rates of STSG uptake compared with patients with Adult Comorbidity Evalution-27 scores of 0 to 2 (65.9% vs 82.9%), with an effect size of 0.599 (95% CI, −0.191 to 1.389). No donor site infections were noted in either group. Conclusions and Relevance Fourteen-day bolster application to the fibula free flap donor site was associated with better STSG uptake rates than 5-day bolster application.
Characterization of lung-to-finger circulation time in sleep study assessment: the Multi-Ethnic Study of Atherosclerosis.

Introduction Lung to finger circulation time (LFCT) measured from sleep studies may reflect underlying cardiac dysfunction. We aimed to examine the distribution of LFCT in community-dwelling men and women in order to better understand the factors determining LFCT between and within subjects. Methods We included participants of the Multi-Ethnic Study of Atherosclerosis (MESA) Sleep with polysomnography-based evidence of sleep apnea (defined by apnea hypopnea index>15/hr). In a randomly selected subset of the analytical dataset, we tested an automated LFCT measurement method against the visual method. Using the automated method we then scored LFCTs from all eligible respiratory events for all included participants. A multiple regression model was constructed to determine factors independently associated with average LFCT across subjects. We also explored factors that are associated with LFCT within subjects using linear mixed-effect models. Results In a subset of the cohort (N=39) there was a high correlation in average LFCT obtained by automated and visual methods (r= 0.96). In the analysis of 596 participants, men [19.6 (2.8)] (vs. women [17.9 (2.7) sec], p 69 (vs. ≤ 69) had longer average LFCT (19.4 [2.8] vs. 18.5 [2.9] sec, p<0.0001). These associations persisted in multivariable analysis. No association was found with body habitus. Within subject analysis revealed trivial associations between apnea/hypopnea duration, apnea (vs. hypopnea), nadir O2 saturation and sleep stages (N vs. R) and individual LFCT. Conclusion Automated LFCT measurement was highly correlated with visual-based LFCT measurement. In this group of community dwelling adults, male sex and older age were associated with higher average LFCT.
2.25 – Corrosion in Acid Gas Solutions

Corrosion in solutions of acidic gases, notably carbon dioxide and hydrogen sulfide, is very important in oil and gas production and can be expected to become important in processes for the sequestration of carbon dioxide. Carbon dioxide exhibits an equilibrium between dissolved CO2 and carbonic acid, and this effectively buffers the hydrogen ion concentration, such that the rate of hydrogen evolution is much higher than for a solution of a strong acid with the same pH. Corrosion in CO2 solution can be modeled using conventional electrochemical kinetic theory, and the results are in good agreement with experimental observations. Corrosion in H2S solution is less well understood, but models can be developed based on the premise that corrosion occurs through surface films of iron sulfide.
An Alternative Route for Astaxanthin Biosynthesis in Green Algae.

Astaxanthin is the reddish carotenoid pigment that gives color to shrimp, salmon, and flamingo. However, these animals do not synthesize astaxanthin by themselves. Instead, microalgae are the initial producers of astaxanthin in nature. Because of its strong antioxidant activity and potential
Future Coastal Population and Ecosystem Exposure to Sea Level Rise Along the European Coastline

The average global sea level has been predicted to rise anywhere between 0.53–2.5 m by 2100 with some local and regional variations in various climate change scenarios. Relative sea level change along most of the European coastline is similar to the global average. The objective of this paper is to estimate the extent of impact regarding three sea level rise (SLR) scenarios on European coastal regions. First, three inundation models estimate the area affected by the base sea level, 1 m SLR, and 2 m SLR. Then, based on the population and land cover classes in the coastal regions, land cover types and the estimated future population affected by the SLR scenarios are analyzed. This study used an inundation model (EU-DEM v1.1 digital elevation model). Land cover data from CLC2018 and monthly averaged sea level anomalies (SLA) files from 2013 to 2015 were used in the model. In the SLR0 scenario, about 8.7 million people are estimated to be affected at 2100. An estimated 11.6 million people will be affected in the SLR1 scenario; and an estimated 14.8 million people will be affected by the SLR2 scenarios. Arable lands and pastures are the two top land cover classes that will be affected by SLR. However, land under urban fabric and transportation are also two important land cover types affected by SLR which can induce major economic costs to coastal countries. A significant area of underwater bodies and wetlands will come in contact with sea water due to the extreme events caused by SLR.
Exploration of Smart Grid Device Cybersecurity Vulnerability Using Shodan

The generation, transmission, distribution, and storage of electric power is becoming increasingly decentralized. Advances in Distributed Energy Resources (DERs) are rapidly changing the nature of the power grid. Moreover, the accommodation of these new technologies by the legacy grid requires that an increasing number of devices be Internet connected so as to allow for sensor and actuator information to be collected, transmitted, and processed. With the wide adoption of the Internet of Things (IoT), the cybersecurity vulnerabilities of smart grid devices that can potentially affect the stability, reliability, and resilience of the power grid need to be carefully examined and addressed. This is especially true in situations in which smart grid devices are deployed with default configurations or without reasonable protections against malicious activities. While much work has been done to characterize the vulnerabilities associated with Supervisory Control and Data Acquisition (SCADA) and Industrial Control System (ICS) devices, this paper demonstrates that similar vulnerabilities associated with the newer class of IoT smart grid devices are becoming a concern. Specifically, this paper first performs an evaluation of such devices using the Shodan platform and text processing techniques to analyze a potential vulnerability involving the lack of password protection. This work further explores several Shodan search terms that can be used to identify additional smart grid components that can be evaluated in terms of cybersecurity vulnerabilities. Finally, this paper presents recommendations for the more secure deployment of such smart grid devices.
The Quality of Care of Transgender and Gender Nonconforming Patients: The Provider Perspective.

Background Transgender and gender-nonconforming (TGNC) patients have inadequate quality of care. Few studies have examined the issues related to quality of care from the perspective of providers. The purpose of this pilot study was to understand the barriers and facilitators of quality TGNC care and develop recommendations for health systems. Methods We used phenomenological methods in the form of qualitative semistructured interviews to allow provider participants to elaborate about issues not covered in the script questions. Audio files from 11 provider interviews were transcribed and summarized by common themes. Thematic analysis was conducted in an iterative process to extract insights from the data. Results Six main subthemes resulted from our qualitative review regarding "barriers to quality care": 1) provider training and knowledge of TGNC care, 2) provider and staff interactions with TGNC patients, 3) case management, 4) misgendering, 5) access and continuity of care, and 6) bias and discrimination. Four subthemes were identified as "facilitators of quality care" for TGNC patients: 1) skilled staff, 2) continuity of care and electronic health records, 3) organizational support, and 4) provider-patient interactions. Additional needs were also suggested. Conclusions Findings were distilled into 3 recommendations to improve the quality of TGNC care: 1) establish a dedicated case-management team; 2) provide access to more in-depth and meaningful training for providers, clinic staff, and administrative staff (and mandate certain basic training); and 3) allocate financial resources and enforce a policy of nondiscrimination.
Regulatory mechanisms of neutrophil migration from the circulation to the airspace

The neutrophil, a short-lived effector leukocyte of the innate immune system best known for its proteases and other degradative cargo, has unique, reciprocal physiological interactions with the lung. During health, large numbers of ‘marginated’ neutrophils reside within the pulmonary vasculature, where they patrol the endothelial surface for pathogens and complete their life cycle. Upon respiratory infection, rapid and sustained recruitment of neutrophils through the endothelial barrier, across the extravascular pulmonary interstitium, and again through the respiratory epithelium into the airspace lumen, is required for pathogen killing. Overexuberant neutrophil trafficking to the lung, however, causes bystander tissue injury and underlies several acute and chronic lung diseases. Due in part to the unique architecture of the lung’s capillary network, the neutrophil follows a microanatomic passage into the distal airspace unlike that observed in other end-organs that it infiltrates. Several of the regulatory mechanisms underlying the stepwise recruitment of circulating neutrophils to the infected lung have been defined over the past few decades; however, fundamental questions remain. In this article, we provide an updated review and perspective on emerging roles for the neutrophil in lung biology, on the molecular mechanisms that control the trafficking of neutrophils to the lung, and on past and ongoing efforts to design therapeutics to intervene upon pulmonary neutrophilia in lung disease.
Childhood maltreatment and within-person associations between cortisol and affective experience.

Glucocorticoids exert profound effects on the brain and behavior, but cortisol concentrations are rarely linked to subjectively reported emotional states in humans. This study examined whether the ...
$${\mathcal {W}}_\infty $$ W ∞ -transport with discrete target as a combinatorial matching problem

In this short note, we show that given a cost function c, any coupling $$\pi $$ of two probability measures where the second is a discrete measure can be associated to a certain bipartite graph containing a perfect matching, based on the value of the infinity transport cost $$\Vert c \Vert _{L^\infty (\pi )}$$ . This correspondence between couplings and bipartite graphs is explicitly constructed. We give two applications of this result to the $${\mathcal {W}}_\infty $$ optimal transport problem when the target measure is discrete, the first is a condition to ensure existence of an optimal plan induced by a mapping, and the second is a numerical approach to approximating optimal plans.
Battlefield Acupuncture Versus Standard Pharmacologic Treatment of Low Back Pain in the Emergency Department: A Randomized Controlled Trial.

Abstract Background Battlefield acupuncture (BFA) offers a novel analgesic option that avoids the need for pharmacologic interventions with problematic side effect profiles. Objective To compare BFA with standard pharmacologic interventions to treat patients in the emergency department (ED) with low back pain. Methods We conducted a nonblinded randomized controlled trial of a convenience sample of adults presenting to an urban tertiary care ED with a chief complaint of low back pain. We randomized subjects to undergo either BFA or the control arm in which they received standard pharmacologic therapies at the discretion of their treating clinician. The primary outcome was mean pain reduction measured on a 100-mm visual analogue scale (VAS) from enrollment to 30–40 min postintervention. Secondary outcomes included the Back Pain Functional Scale (BPFS; scores range from 0–60) measured at 30–40 min postintervention and again at 48–72 h postintervention. Results We enrolled 52 subjects with 26 randomized to each arm. The mean decrease in pain VAS was 33.4 mm among patients undergoing BFA vs. 21.5 mm in the control arm (effect size difference 12.0 mm [95% confidence interval {CI} 0.1–23.8 mm]). The median improvement in the BPFS score at 48–72 h postintervention was 12.0 among patients undergoing BFA vs. 8.0 in the control arm (effect size difference 4 [95% CI −9.0 to 16.0]). There were no adverse events. Conclusions BFA shows promise for further study as an alternative to standard pharmacologic interventions among adults presenting to the ED with low back pain. © 2021 Elsevier Inc.
Optimal Quantizer Structure for Maximizing Mutual Information Under Constraints

Consider a channel whose the input alphabet set $\mathbb {X}=\{x_{1},x_{2}, {\dots },x_{K}\}$ contains $K$ discrete symbols modeled as a discrete random variable $X$ having a probability mass function $\mathbf {p}(\mathbf {x}) = [p(x_{1}), p(x_{2}), {\dots }, p(x_{K})]$ and the received signal $Y$ being a continuous random variable. $Y$ is a distorted version of $X$ caused by a channel distortion, characterized by the conditional densities $p(y|x_{i})=\phi _{i}(y)$ , $i=1,2, {\dots },K$ . To recover $X$ , a quantizer $Q$ is used to quantize $Y$ back to a discrete output $\mathbb {Z} =\{z_{1}, z_{2}, {\dots }, z_{N}\}$ corresponding to a random variable $Z$ with a probability mass function $\mathbf {p}(\mathbf {z}) = [p(z_{1}), p(z_{2}), {\dots }, p(z_{N})]$ such that the mutual information $I(X;Z)$ is maximized subject to an arbitrary constraint on $\mathbf {p}(\mathbf {z})$ . Formally, we are interested in designing an optimal quantizer $Q^{*}$ that maximizes $\beta I(X;Z) - C(Z)$ where $\beta $ is a positive number that controls the trade-off between maximizing $I(X;Z)$ and minimizing an arbitrary cost function $C(Z)$ . Let $\mathbf {p}(\mathbf {x}|y)=[p(x_{1}|y),p(x_{2}|y), {\dots },p(x_{K}|y)]$ be the posterior distribution of $X$ for a given value of $y$ , we show that for any arbitrary cost function $C(.)$ , the optimal quantizer $Q^{*}$ separates the vectors $\mathbf {p}(\mathbf {x}|y)$ into convex regions. Using this result, a method is proposed to determine an upper bound on the number of thresholds (decision variables on $y$ ) which is used to speed up the algorithm for finding an optimal quantizer. Numerical results are presented to validate the findings.
Kt/V (and especially its modifications) remains a useful measure of hemodialysis dose

Removal of small molecular weight solutes shows a strong relationship to hemodialysis outcomes. In contrast, survival with high-flux dialysis or hemodiafiltration is only slightly better than with low-flux hemodialysis. Despite laboratory evidence regarding toxicity of protein-bound uremic solutes, few data exist showing that increased removal of this class of molecules impacts outcomes. In the FHN trials, there was no effect of frequent dialysis, including frequent and long dialysis, on nutrition or control of anemia, outcomes expected to be sensitive to uremic toxin removal; the main benefit appeared to be better volume control. Scaling of hemodialysis dose to total body water may not be optimal. Kt/V scaling to body surface area and use of a continuous measure such as standard Kt/V reduces the likelihood of underdialysis of small patients, including children, and women. Minimum hemodialysis time may best be considered in respect to ultrafiltration rate, and a maximum target ultrafiltration rate unscaled to body size may be optimal. Intensive, extended dialysis may cause adverse effects to residual kidney function, and more information needs to be collected to better understand how urine volume modifies dose requirements, and how to maximize the chances of preserving residual kidney function.
Adenosine Pretreatment of Human Myocardium and Ischemic Preconditioning

To the Editor: I congratulate Leesar et al1 for their innovative research. Evidences are mounting to indicate that ischemic preconditioning (IPC) can be demonstrated in human myocardium,2 3 4 and this has stimulated interest in its potential clinical applicability. However, their study is not the first to demonstrate that adenosine (ADO) pretreatment can protect against myocardial reperfusion injury. In 1993, ADO was infused into the right ventricle of patients undergoing CABG operations.5 It has been conclusively demonstrated for the first time that ADO pretreatment before the …
Cellular Mechanisms for Developmental Toxicity of Chlorpyrifos: Targeting the Adenylyl Cyclase Signaling Cascade☆

Developmental neurotoxicity caused by chlorpyrifos exposure is generally thought to target cholinesterase but chlorpyrifos may also act on cellular intermediates, such as adenylyl cyclase, that serve global functions in the coordination of cell development. In the current study, neonatal rats were exposed to apparently subtoxic doses of chlorpyrifos (no weight loss, no mortality) either on Postnatal Days 1-4 or on Postnatal Days 11-14, and the effects on components of the adenylyl cyclase cascade were evaluated in brain regions that are enriched (forebrain) or sparse (cerebellum) in cholinergic innervation, as well as in a nonneural tissue (heart). In all three, chlorpyrifos evoked deficits in multiple components of the adenylyl cyclase cascade: expression and activity of adenylyl cyclase itself, functioning of G-proteins that link neurotransmitter and hormone receptors to cyclase activity, and expression of neurotransmitter receptors that act through this cascade. Disruption of signaling function was not restricted to transduction of cholinergic signals but rather extended to adrenergic signals as well. In most cases, the adverse effects were not evident during the immediate period of chlorpyrifos administration, but appeared after a delay of several days. These results suggest that chlorpyrifos can affect cell development by altering the activity and reactivity of the adenylyl cyclase signaling cascade, a major control point for trophic regulation of cell differentiation. The effects are not restricted to cholinergic targets, nor even to the central nervous system. Hence, disruption of cell development by chlorpyrifos is likely to be more widespread than previously thought.
Integrating the IEP and SOI with Educational Programing for the Gifted

Given the advent of PL 94-142, this paper investigates a strategy for integrating the IEP and SOI in order to promote an accountability-based approach to differentiated programing for the gifted classroom student. Specifically, critical components of the IEP are identified, relevant features of the SI model outlined, and a system for deriving instructional and behavioral objectives from the SOI Profile is reviewed. The use of computer retrieval data banks with the system presented is discussed in light of the importance of optimal instructional intervention with the gifted.
Strategies for Modeling Exchange Rates and Capital Flows in Multi-Country Macroeconomic Models

The paper surveys exchange rate models, but in a way that differs from existing surveys because it focusses on alternatives available for inclusion in structural multi-country models. It emphasizes that non-structural time-series models or reduced forms are not useful in this context: what is needed are structural models that are theoretically consistent with the rest of the model, whether or not they outperform a random walk. Alternative exchange rate and capital flow specifications that are both tractable and satisfy world adding-up constraints are proposed, and the modeling of expectations is discussed.
The Other Great Exhibition: Mayhew’s Catalog of the Industrious

Henry Mayhew’s London Labour and the London Poor has always had an enthusiastic following, but scholarship on it has been limited and scholars fairly restrained in response to it. This essay examines questions about Mayhew’s sample set (the working-class or the lumpenproleteriat? the poor or the marginal?), the veracity of his interviews, his relations with his subjects, and the publication history of his text. While he has been read as a proto-sociologist, this essay, following Christopher Herbert, suggests that it is more fruitful to view Mayhew’s project as an early-ethnographic effort. The review of Mayhew criticism concludes with a brief reading of Mayhew’s presentation of the street-folk involved in reclaiming wastes – a project that has clear affinities with Mayhew’s own work.
A Novel Mechanism of V Type Zinc Inhibition of Glutamate Dehydrogenase Results from Disruption of Subunit Interactions Necessary for Efficient Catalysis

Bovine glutamate dehydrogenase is potently inhibited by zinc and the major impact is on V(max) suggesting a V-type effect on catalysis or product release. Zinc inhibition decreases as glutamate concentrations decrease suggesting a role for subunit interactions. With the monocarboxylic amino acid norvaline, which gives no evidence of subunit interactions, zinc does not inhibit. Zinc significantly decreases the size of the pre-steady state burst in the reaction but does not affect NADPH binding in the enzyme-NADPH-glutamate complex that governs the steady state turnover, again suggesting that zinc disrupts subunit interactions required for catalytic competence. While differential scanning calorimetry suggests zinc binds and induces a slightly conformationally more rigid state of the protein, limited proteolysis indicates that regions in the vicinity of the antennae regions and the trimer-trimer interface become more flexible. The structures of glutamate dehydrogenase bound with zinc and europium show that zinc binds between the three dimers of subunits in the hexamer, a region shown to bind novel inhibitors that block catalytic turnover, which is consistent with the above findings. In contrast, europium binds to the base of the antenna region and appears to abrogate the inhibitory effect of zinc. Structures of various states of the enzyme have shown that both regions are heavily involved in the conformational changes associated with catalytic turnover. These results suggest that the V-type inhibition produced with glutamate as the substrate results from disruption of subunit interactions necessary for efficient catalysis rather than by a direct effect on the active site conformation.
Mechanism of scorpion toxin-induced enzyme secretion in rat pancreas

Scorpion venom induces acute pancreatitis in humans and stimulates pancreatic hypersecretion in several animal species. To clarify whether scorpion toxin influences pancreatic function directly by stimulating the acinar cells or influences pancreatic function indirectly by stimulating pancreatic nerves, we measured amylase release from both rat pancreas lobules (containing both acinar cells and nerves) and isolated rat pancreatic acini (acinar cells only). Scorpion toxin stimulated amylase release from lobules to a similar extent as did carbamylcholine, an acetylcholine agonist. In these lobules, the effect of scorpion toxin was blocked by both atropine (an inhibitor of the cholinergic receptor on acinar cells) and tetrodotoxin (a selective blocker of Na+ channels in nerves). In contrast, the effect of carbamylcholine was blocked by atropine, but not by tetrodotoxin. In isolated pancreatic acini, carbamylcholine was without effect. We conclude that scorpion toxin influences pancreatic function indirectly by stimulating the release of acetylcholine from pancreatic nerves.
Interventions to Increase Hand Hygiene Behavior among University Students: Implications for Response Cost and Socially-Assisted Interventions

A field study was conducted to examine the effect of interventions to increase hand-hygiene behavior of university students. Student patrons of a university cafeteria were observed during lunch. Across several phases, researchers observed and recorded the number of students (a) entering the restroom to wash hands and (b) using a hand-sanitizer gel. Interventions included an informational poster, hand-sanitizer dispenser, and change agent to increase hand-hygiene behavior. Results showed that the presence of a strategically placed hand-sanitizer dispenser was effective in increasing hand-hygiene behavior from 1.52% to over 60% (average n = 208 students per day). Participants were particularly responsive to the hand-sanitizer dispenser when combined with a change agent. Meanwhile, the tested interventions were ineffective in increasing the number of students entering a restroom to hand wash. The results are discussed regarding response cost and socially-mediated consequences of change agents.
VOCAL CORD PARALYSIS IN INFANTS AND CHILDREN

Vocal cord paralysis is the second most common cause of neonatal stridor. Recognition of laryngeal paralysis warrants further evaluation for an underlying etiology as it is frequently a manifestation of a multisystem anomaly. Initial intervention must concentrate on airway stabilization and treatment of any underlying conditions. Management strategies should be individualized and focus on maintenance of a safe and stable airway, acquisition of intelligible speech, and deglutition without aspiration.
A programmable self-adaptive digital frequency multiplier

Existing self-adaptive frequency multipliers work well if the master clock frequency is an integral multiple of the input signal frequency; otherwise they lose an output pulse after a certain interval of time. The frequency of this missing pulse could be as high as half of the input frequency. Since existing self-adaptive frequency multipliers are not programmable, the multiplication factor can not be changed without doing some major changes in the hardware. The reason for missing an output pulse is explained, and design and implementation of a programmable self-adaptive digital frequency multiplier, that does not have this missing pulse problem are presented. The errors associated with the multiplier are discussed. >
Boundary Layer Theory to Matched Asymptotics

We describe the explanation of Prandtl's boundary layer theory by Friedrichs, leading to the boundary layer technique, or the method of matched asymptotics. The latter provides a systematic procedure for the formulation of a singular perturbation problem, the matching of local (inner) and global (outer) perturbation solutions, the identification of the “lost” boundary condition(s) from the full system of equations and the derivation of the higher order equations and their compatibility condition(s), if any, which would be the closure condition(s) of the leading order solutions. Examples using the method of matched asymptotics are presented to demonstrate the “lost” condition(s) and the closure condition(s) and to emphasize the physical intuition needed to formulate the perturbation problem, i.e., the choice of the scalings and the expansion schemes, the physical meaning of the inner solution, and its matching with the outer solution, etc.
Case Study of Above Average Elementary School

This case study explores the duty of midmanagement administrators to enforce district policies with which they do not necessarily agree. The case addresses the issues of moral leadership, distribution of power, emotional responses that impact decision making, class differences, and equity. It also examines the role conflict that many married female principals bring to the job description. Issues of class and the growing inequities in the class structure of the United States are pivotal to the discussion. This case can be used in classes that consider gender and leadership, decision making, equity, moral leadership, organizational change, policy implementation, and community/school relations.
Carbonate facies of the Upper Triassic Ojo Huelos Member, San Pedro Arroyo Formation (Chinle Group), southern New Mexico: Paleoclimatic implications

Abstract The Upper Triassic (Adamanian LVF) Ojo Huelos Member of the San Pedro Arroyo Formation (Chinle Group) is a distinctive, carbonate-rich unit that occurs in the lower Chinle section of central New Mexico. The member consists mainly of micritic lime mudstones, ostracodal wackestones to grainstones, peloidal grainstones and distinctive pisolitic rudstones, interbedded with fine-grained siliciclastic mudstones. Most limestones exhibit some evidence of pedogenic brecciation and root penetration, and porous fabrics similar to those of modern limestone tufas occur locally. The interbedded mudstones are typically lenticular and commonly display a blocky ped fabric in which subequant peds are separated by sparry calcite veins. Fossils from the Ojo Huelos Member are freshwater (darwinulid) ostracodes, various freshwater fishes and aquatic/amphibious tetrapods–metoposaurs and phytosaurs. We interpret the carbonate facies as the deposits of carbonate lakes, ponds and wetlands that were partly spring-fed, whereas the interbedded and surrounding mudstones were alluvial in origin. The groundwater and overland hydrology of the region was likely controlled by the relative proximity to an upland recharge area in the Mogollon Highlands to the south, but sedimentary fabrics record strong overprinting by desiccation and pedogenic reworking. Consequently, we interpret the Ojo Huelos Member as recording a climate that varied from subhumid to semi-arid, which caused episodic falls in the hydrologic base-level. This resulted in landscape degradation, exemplified by significant pedogenic and erosional reworking of the carbonate sediments and fluvial incision.
The Snakes and Ladders Game in E-Business: Digital Transformation at American Hardware Depot

American Hardware Depot (AHD), a retailer of hardware and home improvement products, sells over 65,000 products through its network of 4,500 stores nationwide that are operated by owner dealers. While rivals such as Home Depot were quick to launch their e-business efforts, AHD was late to embrace technology as well as electronic retailing. Though some of the AHDâ€™s e-business efforts met with moderate success, others faced severe challenges. AHD invested over $5 million as a minority equity stake in Americanhome.com in return for this dot-com firm acting as an online front-end store for AHDâ€”however, this effort failed within a year. AHD was at a critical inflexion point. AHD seeks to enhance its e-business efforts in at least three major areas: (1) to connect its dealers who had varied business processes and technologies, (2) to market and sell its products through the Web, and (3) to streamline its supply chain operations. A newly appointed vice president of e-business has to find solutions to the challenges facing AHD.
Modeling Socioeconomic Class in Variationist Sociolinguistics

Modeling socioeconomic class has been a persistent challenge in the analysis of sociolinguistic variation. While early stratificational models formulated on the basis of socioeconomic indicators such as income, occupation, and area of residence revealed compelling patterns of linguistic variation, they were critiqued for their lack of explanatory power at the interactional level and for their marginalization of those without paid employment. Subsequent models have employed cross-disciplinary concepts such as the linguistic market, social networks, and communities of practice, prioritizing local social distinctions that are understood to reflect or even constitute abstract structural categories such as ‘working class’ or ‘middle class’. It is argued that a full socioeconomic class paradigm for sociolinguistics would also theorize class at the aggregate level, and to this end, sociological class models may prove useful. Contemporary sociological class analysis at the level of social practice offers additional avenues for interfacing with sociology.
On the alignment of cellulose microfibrils by cortical microtubules: a review and a model.

The hypothesis that microtubules align microfibrils, termed the alignment hypothesis, states that there is a causal link between the orientation of cortical microtubules and the orientation of nascent microfibrils. I have assessed the generality of this hypothesis by reviewing what is known about the relation between microtubules and microfibrils in a wide group of examples: in algae of the family Characeae,Closterium acerosum, Oocystis solitaria, and certain genera of green coenocytes and in land plant tip-growing cells, xylem, diffusely growing cells, and protoplasts. The salient features about microfibril alignment to emerge are as follows. Cellulose microfibrils can be aligned by cortical microtubules, thus supporting the alignment hypothesis. Alignment of microfibrils can occur independently of microtubules, showing that an alternative to the alignment hypothesis must exist. Microfibril organization is often random, suggesting that self-assembly is insufficient. Microfibril organization differs on different faces of the same cell, suggesting that microfibrils are aligned locally, not with respect to the entire cell. Nascent microfibrils appear to associate tightly with the plasma membrane. To account for these observations, I present a model that posits alignment to be mediated through binding the nascent microfibril. The model, termed templated incorporation, postulates that the nascent microfibril is incorporated into the cell wall by binding to a scaffold that is oriented; further, the scaffold is built and oriented around either already incorporated microfibrils or plasma membrane proteins, or both. The role of cortical microtubules is to bind and orient components of the scaffold at the plasma membrane. In this way, spatial information to align the microfibrils may come from either the cell wall or the cell interior, and microfibril alignment with and without microtubules are subsets of a single mechanism.
City Bound: Political Science and the American Metropolis

The study of urban politics was once central to the political science discipline in the United States. As central cities have lost their dominant position in the metropolis, however, political science's urbanists have remained fixated on the conflicts and crises of the urban core, while largely ignoring urban politics that occurs outside the city limits. This focus has resulted in a skewed understanding of urban America, and may limit the analytical contributions of the field as well. We review the development of the urban politics literature and offer some explanations for its preoccupation with big cities. We argue that work in this field would be better integrated if urban politics were reconceptualized as the politics of urbanization. We suggest some new theoretical and substantive contributions that such an approach would permit, and emphasize that the politics of urbanization cannot be fully understood in city-bound analysis. By examining political conflicts and processes in central cities, scholars of urban politics in the first two thirds of this century identified concepts and research questions that were central to the development of American political science. In recent years, however, the work of political science's urbanists has not contributed as frequently to broad dialogues in the discipline. Instead, scholars in this field have engaged in insular (if often fascinating) debates, frequently choked with specialized jargon. (See the critiques in Peterson 1981: preface; Jones 1989.) In so doing, attention has remained focused, to an extreme degree, on big cities. We contend that scholarship in the field, accordingly, has offered a highly skewed perception of contemporary urban political phenomena. This article reviews the development of the field, and offers some explanations for its preoccupation with larger cities. It then argues for a reconsideration of what urban politics denotes. Such a clarified conception of their subject matter would take scholars of urban politics far beyond the city limits. It would not preclude their engaging in the whole host of research topics that have traditionally marked the field, but would lend more analytical coherence to such inquiry.
Uptake, Tissue Distribution, and Excretion of 14C-Sulfur Mustard Vapor Following Inhalation in F344 Rats and Cutaneous Exposure in Hairless Guinea Pigs

Sulfur mustard (SM), a vessicating agent, has been used in chemical warfare since 1918. The purpose of this study was to quantitate SM vapor deposition, tissue distribution, and excretion following intratracheal inhalation in rats and cutaneous exposure in guinea pigs. 14C-SM vapors for inhalation studies were generated by metering liquid 14C-SM into a heated J tube. Vapors were transported via carrier air supplemented with oxygen and isoflurane to an exposure plenum. Anesthetized rats with transorally placed tracheal catheters were connected to the plenum port via the catheter hub for exposure (approximately 250 mg 14C-SM vapor/m(3); 10 min). For dermal exposure, 3 Teflon cups (6.6 cm(2) exposure area per cup) were applied to the backs of each animal and vapors (525 mg 14C-SM/m(3); 12 min) were generated by applying 6 μl 14C-SM to filter paper within each cup. Animals were euthanized at selected times up to 7 d postexposure. SM equivalents deposited in rats and guinea pigs were 18.1 ± 3 μg and 29.8 ± 5.31 μg, respectively. Inhaled SM equivalents rapidly distributed throughout the body within 2 h postexposure, with the majority (>70%) of material at that time located in carcass and pelt. In guinea pigs, >90% of deposited SM equivalents remained in skin, with minor distribution to blood and kidneys. Urine was the primary route of excretion for both species. Results indicate inhaled SM is rapidly absorbed from the lung and distributed throughout the body while there is limited systemic distribution following cutaneous exposure.