cssi/SciSciGPT-SciSciNet huggingface dataset:
Pediatric Congenital and Miscellaneous Lung Abnormalities

Congenital lung abnormalities are common in pediatric patients. While these lung malformations may be incidental findings in some children, they can also result in various symptoms and imaging findings depending on their size, location, as well as connection to and mass effect upon the adjacent thoracic structures. Imaging plays an important role for early and correct diagnosis, which in turn can improve pediatric patient care by guiding the appropriate next step in management. In this chapter, we discuss clinical presentation and imaging findings of common congenital lung abnormalities in the pediatric population. In addition, rare but important other congenital malformations such as horseshoe lung, hepatopulmonary fusion, bronchobiliary fistula (BBF), and cast bronchitis are reviewed. Familiarity with the characteristic clinical and imaging findings of congenital lung abnormalities can avoid delay in diagnosis and optimize pediatric patient care.
Preoperative hyponatremia is an independent risk factor for postoperative complications in aseptic revision hip and knee arthroplasty

Abstract Introduction The purpose of this study is to investigate the relationship between preoperative hyponatremia and postoperative complications in aseptic revision hip and knee arthroplasty. Methods Aseptic revision arthroplasties from 2007 to 2016 were collected using a large, United States database. Patients were stratified into eunatremic and hyponatremic cohorts. Rates of complications were collected and analyzed. Results 25,517 surgeries were evaluated. Preoperative hyponatremia was independently associated with organ/space infections (OR= 2.316; p Conclusion Hyponatremia is an independent risk factor for several postoperative complications in aseptic revision hip and knee arthroplasty.
Lifetime and prospective associations among personality trait domains and suicide-related behaviors in patients with severe mental illness

Abstract Background Despite extensive research and clinical efforts, the suicide rate in the United States continues to rise, driving the need for more research to identify latent factors that increase risk for suicide and to guide treatment decision-making. Methods The current study examined a large cohort (N = 1,219) of high-risk psychiatric inpatients to explore associations between personality traits and suicide-related variables measured retrospectively (lifetime history prior to hospital admission) and prospectively (at discharge and 12-month follow-up). Results Lifetime suicide-related behavior (SRB: combination of ideational severity, aborted, interrupted, actual attempts, and non-suicidal self-injury) was associated with age (younger), gender (female), and elevated scores on the Personality Inventory for DSM-5 (PID-5) negative affectivity, borderline trait composite score, and five-factor model traits of conscientiousness and neuroticism. Patients who manifested persistent suicidal ideation throughout a 6–8 week inpatient treatment (n = 162; 16.9%) tended to be younger, female, and to have elevated PID-5 borderline trait composite scores. Twelve-month post-discharge SRB was predicted by elevated PID-5 borderline trait composite scores. Limitations Personality traits accounted for a small amount of variance in the overall model, thus limiting prediction based on individual traits. Conclusions This large sample of high-risk inpatients with longitudinal outcomes provides a rare assessment of proximal personality traits in predicting lifetime SRB, persistent suicidal ideation observed during the course of a 6–8-week intensive inpatient treatment, and SRB outcomes within 12 months after discharge from hospitalization. Personality traits should be included in future attempts to create predictive algorithms that include relevant biological data (neuroimaging, genetic, microbiome).
Obsessive Work Passion as a Conduit between Work-Contingent Self-Esteem and Abusive Supervision

Building on self-determination theory and the dualistic model of passion, the study proposes two alternative perspectives to understanding antecedents of abusive supervision. The subordinate-induce...
Integrated Management of Wealth and Risk: First Principles

The objective of this paper is to explore two frequently ignored principles for the prudential management of financial systems at all levels of aggregation from a single individual to a national government. One of the ironies of the current global financial crisis is that the very innovations designed to mitigate risks have been identified as causes of the huge losses in wealth. But it is not the innovations that caused the cascade of losses; it was violations of the principles of prudent wealth management. This chapter explores some of those principles and illustrates how they have been violated by individuals, banks, pension funds, and government guarantee funds. The principles are: Principle #1. Safety First. When faced with choices involving risk, start by identifying the safest choice, and use it as a reference point for evaluating more risky choices. A risk premium can only be earned by taking genuine risk. If you choose to take risk, be prepared for the possibility that a worse outcome might occur. Principle #2. Mark to Market. Use market prices and fair value accounting for all assets and liabilities. Beware of illusory arbitrage opportunities created by use of accounting rules that violate market realities. If an investment opportunity seems too good to be true, it is probably not true. The destabilizing feedback loop caused by government guarantees of toobig-to-fail financial institutions, moral hazard, forbearance, and ever bigger government bailouts is familiar to analysts of the U.S. banking system. It is less familiar, but no less pernicious, in the case of the pension system. In the case of pensions, however, the vicious cycle is less transparent because of the fallacious belief that the risk of equities goes away in the long run. Until there is a recognition that equities are not a match for the fixed liabilities of defined-benefit pension liabilities, it will remain a serious source of financial instability for the U.S. economy.
A computationally efficient model to represent the chemistry, thermodynamics, and microphysics of secondary organic aerosols (simpleSOM): model development and application to α-pinene SOA

Secondary organic aerosols (SOA) constitute an important fraction of fine-mode atmospheric aerosol mass. Frameworks used to develop SOA parameters from laboratory experiments and subsequently used to simulate SOA formation in atmospheric models make many simplifying assumptions about the processes that lead to SOA formation in the interest of computational efficiency. These assumptions can limit the ability of the model to predict the mass, composition, and properties of SOA accurately. In this work, we developed a computationally efficient, process-level model named simpleSOM to represent the chemistry, thermodynamic properties, and microphysics of SOA. simpleSOM simulates multigenerational gas-phase chemistry, phase-state-influenced kinetic gas/particle partitioning, heterogeneous chemistry, oligomerization reactions, and vapor losses to the walls of Teflon chambers. As a case study, we used simpleSOM to simulate SOA formation from the photooxidation of α-pinene. This was done to demonstrate the ability of the model to develop parameters that can reproduce environmental chamber data, to highlight the chemical and microphysical processes within simpleSOM, and discuss implications for SOA formation in chambers and in the real atmosphere. SOA parameters developed from experiments performed in the chamber at the California Institute of Technology (Caltech) reproduced observations of SOA mass yield, O : C, and volatility distribution gathered from other experiments. Sensitivity simulations suggested that multigenerational gas-phase aging contributed to nearly half of all SOA and that in the absence of vapor wall losses, SOA production in the Caltech chamber could be nearly 50% higher. Heterogeneous chemistry did not seem to affect SOA formation over the short timescales for oxidation experienced in the chamber experiments. Simulations performed under atmospherically relevant conditions indicated that the SOA mass yields were sensitive to whether and how oligomerization reactions and the particle phase state were represented in the chamber experiment from which the parameters were developed. simpleSOM provides a comprehensive, process-based framework to consistently model the SOA formation and evolution in box and 3D models.
Myeloid cell modulation by a GLP-1 receptor agonist modulates retinal angiogenesis in ischemic retinopathy.

Ischemic retinopathies including diabetic retinopathy are major causes of blindness. While neurons and Muller glia are recognized as important regulators of reparative and pathologic angiogenesis, the role of mononuclear phagocytes (MPs), such as microglia/macrophages, is unclear, particularly microglia, the resident retinal immune cells. Here we found microglial/macrophage activation in human diabetic retinopathy, especially in neovessels from human neovascular membranes in proliferative retinopathy, including TNF-α expression. There was similar activation in the mouse oxygen-induced retinopathy (OIR) model of ischemia-induced neovascularization. Glucagon-like peptide-1 receptor (GLP-1R) agonists are in clinical use for glycemic control in diabetes and are also known to modulate microglia. We investigated the effect of a long-acting GLP-1R agonist, NLY01. Following intravitreal administration, NLY01 selectively localized to MPs in OIR retina. NLY01 modulated MP but not retinal endothelial cell viability, apoptosis, and tube formation in vitro. In OIR, NLY01 treatment inhibited MP infiltration and activation, including microglia/macrophage expression of cytokines in vivo. NLY01 significantly suppressed global induction of retinal inflammatory cytokines, promoted reparative angiogenesis, and suppressed pathologic retinal neovascularization. Collectively, these findings indicate the important role of microglia/macrophages in regulation of retinal vascularization in ischemia and suggest modulation of MPs as a new treatment strategy for ischemic retinopathies.
The Progenitor of the Vela Pulsar

With Gaia parallaxes it is possible to study the stellar populations associated with individual Galactic supernova remnants (SNR) to estimate the mass of the exploding star. Here we analyze the luminous stars near the Vela pulsar and SNR to find that its progenitor was probably (>90%) low mass (8.1-10.3Msun). The presence of the O star gamma2 Vel a little over 100 pc from Vela is the primary ambiguity, as including it in the analysis volume significantly increases the probability (to 5%) of higher mass (>20Msun) progenitors. However, to be a high mass star associated with gamma2 Vel's star cluster at birth, the progenitor would have to a runaway star from an unbound binary with an unusually high velocity. The primary impediment to analyzing large numbers of Galactic SNRs in this manner is the lack of accurate distances. This can likely be solved by searching for absorption lines from the SNR in stars as a function of distance, a method which yielded a distance to Vela in agreement with the direct pulsar parallax. If Vela was a 10Msun supernova in an external galaxy, the 50 pc search region used in extragalactic studies would contain only ~10% of the stars formed in a 50~pc region around the progenitor at birth and ~90% of the stars in the search region would have been elsewhere.
The Role of Methyl CpG Binding Domain Protein 2 (MBD2) in the Regulation of Embryonic and Fetal β-type Globin Genes

xv CHAPTER 1: Introduction and Literature Review 1 I. The human βglobin locus and hemoglobin switching: 1 II. β-hemoglobinopathies: 7 A. Sickle cell disease (SCD): 8 i. Incidence: 9 ii. Pathophysiology: 9 B. Beta thalassemias: 11 i. Incidence: 12 ii. Pathophysiology: 12 C. Management strategies for β-hemoglobinopathies: 14 D. Fetal hemoglobin induction, an effective treatment strategy: 15 III. The human γ-globin gene regulation: 18
Dose-depended modulation of STAT signaling in the atypical/dyaplastic nevus by exposure to interferon α.

5742 Background: IFNα is the only effective adjuvant therapy of melanoma to date. Its effects on risk marker lesions known as atypical / dysplastic nevi have not previously been well documented. We report the initial results obtained in two separate prospective trials testing the STAT signaling effects of high and low doses of IFNα2 administered in vivo for patients with multiple clinically atypical nevi, and a history of melanoma Methods: Two prospective trials were designed to analyze the effects of systemically administered high-dose IFNα2b (HDI) or low-dose IFNα2a (LDI) to patients with 4 or more clinically atypical melanocytic lesions (UPCI 95-071 and UPCI-96-043). Paired biopsies of atypical nevi larger than 4 mm were obtained pre- and post-treatment from patients with a history of primary cutaneous melanoma. HDI [20 × 10 6 units/m 2 IV daily x5/7 days per week × 4 weeks and 10 × 10 6 units/m 2 SCQOD for the subsequent 11 months] or LDI [3 × 10 6 units subcutaneously every other day (M, W, F) three times each week for three months] were administrated to the participants on the two separate protocols. Double-blind analysis was performed for biopsy samples obtained from lesions selected according to a randomization table. Phosphorylated STAT1 tyr701 (pSTAT1) and phosphorylated STAT3 tyr705 (pSTAT3) were probed with indirect immunohistochemistry on the snap frozen sections fixed with acetone. Mean values of the percentages of positive cells are presented with standard errors (SE). Paired-sample permutation tests and Spearman9s rank correlation coefficient r were used for data analysis. Results: 27 patient samples are adequate to be analyzed. The expression level of pSTAT1 is up-regulated while pSTAT3 is down-regulated with the maturing of melanocytes from junction to dermis. With the increment in dysplastia from normal nevus to dysplastic nevus and primary melanoma, pSTAT3 is observed to be progressively up-regulated. The level of pSTAT3 expression correlates with nevus dysplasia (normal, mild, moderate and severe, r=0.44, n=51 and p=0.0013). In junctional melanocytes, pSTAT3 is down-regulated from 40.67 ± 4.76 % to 28.52 ± 3.66 % (p = 0.005) or from 38.7 ± 6.9 % to 18.3 ± 3.8 % (p
Antiproximity effect in aluminum nanowires with no applied magnetic field

The antiproximity effect, where the superconductivity in superconducting nanowires is suppressed or weakened when the wires are contacted by bulk superconducting electrodes, first revealed in arrays of Zn nanowires by tuning the electrodes from the superconducting to the normal state by means of an external magnetic field, has been confirmed in single-crystal aluminum nanowires. The critical current at zero magnetic field of an individual aluminum nanowire contacted by superconducting electrodes was found to be significantly smaller than that with normal electrodes, showing that the effect is not a consequence of the magnetic field.
Short-Term Zinc Deficiency in the Rat and Self-Selection of Dietary Protein Level

The effects of short-term zinc deficiency in rats on the selection of protein were studied. Rats were given a choice of two isocaloric diets containing either 10 or 50% soybean protein, with or without supplemental zinc. In one experiment 5-week-old rats, deprived of dietary zinc, chose a diet with a lower proportion of protein than those fed diets adequate in zinc. The zinc-deprived rats also ate less protein and less total diet than controls, but the same amount of carbohydrate. In a second experiment, 8-week-old rats deprived of adequate dietary zinc chose diets with less protein and more carbohydrate than controls without altering total food intake. Protein intake was inversely correlated with molar ratio of tryptophan to other neutral amino acids in plasma. Tryptophan and serotonin levels in brain, however, were unchanged in zinc deficiency. Brain tyrosine levels and the ratio of tyrosine to other neutral amino acids in plasma were elevated in zinc-deprived rats while brain catecholamine concentrations remained unchanged. These studies show an interaction between zinc and protein in the regulation of food intake and suggest that this could be a useful model to study the determinants of eating behavior.
A Note on Three Statistical Tests in the Logistic Regression DIF Procedure

Although logistic regression became one of the well-known methods in detecting differential item functioning (DIF), its three statistical tests, the Wald, likelihood ratio (LR), and score tests, which are readily available under the maximum likelihood, do not seem to be consistently distinguished in DIF literature. This paper provides a clarifying note on those three tests when logistic regression is applied for DIF detection.
ARgument-based airworthiness assurance of small UAS

A combination of airworthiness and various operational restrictions are currently used to assure that unmanned aircraft system (UAS) operations can be conducted at an acceptable level of safety. We present a methodology to communicate these aspects in a unified way, providing a centralized record of safety risk management (SRM) activities. Central to our approach is the notion of structured argument, i.e., an explicit chain of reasoning linking safety substantiating evidence to the overall safety and airworthiness objectives. Our use of argumentation is motivated, in part, by the observations that: i) certain kinds of UAS operations currently require a safety case; ii) structured arguments are often a core component of modern safety cases, providing a convenient means to represent the underlying reasoning and to access the aggregated safety information; and iii) there exists a standardized graphical notation to present structured arguments, i.e., the goal structuring notation (GSN), which has been used in both civil and military aviation. To exemplify our methodology, we apply it to an unmanned rotorcraft system (URS), using GSN arguments to show the relationship between safety of URS operations, and various SRM measures including airworthiness, in particular a potential certification basis for type design assurance. The example illustrates how our approach can coexist with, and augment, existing safety processes by transforming SRM artifacts into assurance argument fragments.
Polymer deformation and filling modes during microembossing

This work investigates the initial stages of polymer deformation during hot embossing micro-manufacturing at processing temperatures near the glass transition temperature (Tg) of polymer films having sufficient thickness such that polymer flow is not supply limited. Several stages of polymer flow can be observed by employing stamp geometries of various widths and varying imprint conditions of time and temperature to modulate polymer viscosity. Experiments investigate conditions affecting cavity filling phenomena, including apparent polymer viscosity. Stamps with periodic ridges of height and width 4 µm and periodicity 30, 50 and 100 µm emboss trenches into polymethyl methacrylate films at Tg − 10 °C < Temboss < Tg + 20 °C. Imprint parameters of time, temperature and load are correlated with replicated polymer shape, height and imprinted area. Polymer replicates are measured by atomic force microscopy and inspected by scanning electron microscopy. Cavity size and the temperature dependence of polymer viscosity significantly influence the nature of polymer deformation in hot embossing micro-manufacturing and must be accounted for in rational process design.
Lanthanum silicate gate dielectric stacks with subnanometer equivalent oxide thickness utilizing an interfacial silica consumption reaction

A silicate reaction between lanthana and silica layers has been utilized to eliminate interfacial silica in metal-insulator-semiconductor devices and to obtain devices with very low equivalent oxide thickness EOT. This provides a simple process route to interface elimination, while producing a silicate dielectric with a higher temperature stability of the amorphous phase. The La2O3 layers in this study are deposited by reactive evaporation on 001 Si covered by a 0.8– 1.0-nm-thick SiO2 chemical oxide, and are capped in situ with a Ta gate, followed by a reaction anneal, which lowers the EOT from greater than 1.5 nm for the as-deposited bilayer stack to as low as 0.5 nm. Electron energy-loss spectroscopy and medium-energy ion scattering are used to show that a temperature of 400 °C is sufficient for the formation of the silicate gate dielectric. Gate leakage currents as low as 0.06 A / cm 2 are obtained for stacks having an EOT of 0.63 nm, orders of magnitude below that of SiO2 having the same EOT value. Electrical breakdown is observed at applied fields above 16 MV/ cm. © 2005 American Institute of Physics. DOI: 10.1063/1.1988967
National practitioner data bank

EDITOR'S NOTE: As more and more CNMs expand the scope of their practice to include well woman care, the potential for litigation increases. It, thus, behooves the practicing CNM to become familiar with the National Practitioner Data Bank, which is discussed in the following paper.
Microwave optimization of 10 V PJVS circuits

Proper operation of programmable Josephson voltage standard arrays depends on the uniform distribution of microwaves to a large number of Josephson junctions. Too much or too little microwave power will change the current range of a junction's constant voltage step so that an entire array of junctions will have a smaller total current margin. In this paper we discuss the important aspects of microwave power distribution including splitting the microwaves to different arrays, keeping the microwave bias uniform within an array, and minimizing the total input power to the circuit.
Infrared photothermal imaging of trace explosives on relevant substrates

We are developing a technique for the stand-off detection of trace explosives on relevant substrate surfaces using photo-thermal infrared (IR) imaging spectroscopy (PT-IRIS). This approach leverages one or more compact IR quantum cascade lasers, tuned to strong absorption bands in the analytes and directed to illuminate an area on a surface of interest. An IR focal plane array is used to image the surface and detect small increases in thermal emission upon laser illumination. The PT-IRIS signal is processed as a hyperspectral image cube comprised of spatial, spectral and temporal dimensions as vectors within a detection algorithm. The ability to detect trace analytes on relevant substrates is critical for stand-off applications, but is complicated by the optical and thermal analyte/substrate interactions. This manuscript describes recent PT-IRIS experimental results and analysis for traces of RDX, TNT, ammonium nitrate (AN) and sucrose on relevant substrates (steel, polyethylene, glass and painted steel panels). We demonstrate that these analytes can be detected on these substrates at relevant surface mass loadings (10 μg/cm2 to 100 μg/cm2) even at the single pixel level.
Melting temperatures in the gold-phosphorus system

Abstract By use of a high pressure technique, the melting temperature of Au 2 P 3 has been established as 914±2°C and the eutectic temperature between Au 2 P 3 and Au as 895±2°C.
The bloodhound project: automating discovery of web usability issues using the InfoScentπ simulator

According to usability experts, the top user issue for Web sites is difficult navigation. We have been developing auto-mated usability tools for several years, and here we describe a prototype service called InfoScent™ Bloodhound Simula-tor, a push-button navigation analysis system, which auto-matically analyzes the information cues on a Web site to produce a usability report. We further build upon previous algorithms to create a method called Information Scent Absorption Rate, which measures the navigability of a site by computing the probability of users reaching the desired destinations on the site. Lastly, we present a user study involving 244 subjects over 1385 user sessions that show how Bloodhound correlates with real users surfing for in-formation on four Web sites. The hope is that, by using a simulation of user surfing behavior, we can reduce the need for human labor during usability testing, thus dramatically lower testing costs, and ultimately improving user experience. The Bloodhound Project is unique in that we apply a concrete HCI theory directly to a real-world prob-lem. The lack of empirically validated HCI theoretical model has plagued the development of our field, and this is a step toward that direction.
Generation of N-Acyliminium Ions via Intramolecular Conjugate Addition Reactions: A Strategy for the Total Synthesis of Nakadomarin A

The rapid construction of the tetracyclic core ring system of nakadomarin A via a tandem enecarbamate Michael addition/N-acyliminium ion cyclization is described.
Modeling human visual detection of low-contrast objects in fluoroscopy image sequences

We have performed a large variety of perception experiments aimed at issues in x-ray fluoroscopy. These include effects of image acquisition rate, digital temporal filtering, motion, and x-ray system motion blur. In this report, two model structures were considered. Both were non-prewhitening matched filter models modified to include a spatio-temporal visual system contrast sensitivity function. The first model used a spatial template following temporal integration and the second used a spatio-temporal template. The first model best described all data. However, it did not describe all motion experiments as accurately as the second. Our conclusion was that given an experiment, we should use the simplest model which most accurately describes similar experiments. Models will help plan critical experiments, allow one to concisely describe results, and predict similar experiments. Both models will be used to further our ultimate goal of using quantitative image quality studies to minimize dose and maximize image quality in x-ray fluoroscopy.
A Model of the Global and Institutional Antecedents of High-Level Corporate Environmental Performance

Stories of firms that exceed local compliance requirements in their environmental performance appear routinely. However, we have limited theoretical explanations of what propels these firms to exceed compliance. Our theory suggests that global competitive and institutional pressures lead multinational firms to develop highlevel, environmental management systems (EMS) that make them more competitive. For economic and other reasons, select firms make the choice to rationalize their collective environmental performance to the highest common denominator rather than the lowest. Regulations around the world differ widely and are a moving target in many settings. The need to comply with such myriad, shifting rules leads to firms creating EMS to help stay ahead of regulations worldwide. Using institutional and internationalization theories as our basis, we offer a propositional model concerning global competitive/institutional pressures and their effects on corporate environmental performance. We conclude the pap...
Experimental Diagnostics for the Study of Combustion Instabilities in Lean Premixed Combustors

An improved understanding of the mechanisms of unstable combustion in lean premixed combustors is essential to the development of stable gas turbine combustion systems. To obtain such understanding, detailed experimental studies of the phenomenology of unstable combustion are required. A number of experimental diagnostic techniques for characterizing unstable combustion and the underlying instability mechanisms are discussed. This includes techniques based on pressure, chemiluminescence emission, infrared absorption, and laser-induced fluorescence measurements. The techniques themselves are discussed briefly; however, the primary objective is to present and discuss results illustrating how these techniques can be used to characterize the mechanisms of unstable combustion, to gain an improved understanding of unstable combustion, and to develop strategies for suppressing unstable combustion in lean premixed gas turbine combustors.
Competition in Visual Cortex Impedes Attention to Multiple Items

Traditional explanations of our limited attentional capacity focus on our ability to direct attention to multiple items. We ask whether this difficulty in simultaneously attending to multiple items stems from an inability to effectively represent multiple attended items. Although attending to one of a set of neighboring stimuli can isolate it from competitive interactions in visual cortex, no such isolation should occur if multiple competing items are attended. Indeed, we find that attention is ineffective at enhancing blood oxygen level-dependent signal in visual cortical area V4 when it is directed to three stimuli simultaneously, but only when those three stimuli compete in visual cortex. This suggests that competition may prevent attention from acting as effectively on representations of multiple items as it does on representations of a single item. In contrast to traditional explanations that posit limits in the sources of attentional control, we show that mechanisms at the sites of stimulus representation may also impose limits on our ability to attend to multiple items simultaneously.
A Novel Image Classification Algorithm Using Overcomplete Wavelet Transforms

A novel frequency-based classification framework and new wavelet algorithm (Wave-CLASS) is proposed using an overcomplete decomposition procedure. This approach omits the downsampling procedure and produces four-texture information with the same dimension of the original image or window at infinite scale. Three image subsets of QuickBird data (i.e., park, commercial, and rural) over a central region in the city of Phoenix were used to examine the effectiveness of the new wavelet overcomplete algorithm in comparison with a widely used classical approach (i.e., maximum likelihood). While the maximum-likelihood classifier produced $(\text{Kappa}=0.94)$ , 93.71% for the park subset $(\text{Kappa}=0.93)$ , and 89.33% for the rural subset $(\text{Kappa} =0.86) $ . Results from this study demonstrate that the proposed method is effective in identifying detailed urban land cover types in high spatial resolution data.
Is the elimination of postoperative antimicrobial prophylaxis in thoracic surgery ready for prime time?: Comment on "Postoperative antibacterial prophylaxis for the prevention of infectious complications associated with tube thoracostomy in patients undergoing elective general thoracic surgery".

M any retrospective series conclude with the admonition that the findings should be corroborated by a well-designed, randomized clinical trial. With regard to the use of antibiotics following thoracic surgery, that study is now available. Oxman and colleagues provide us with a well-conducted, randomized study suggesting that routinely extending antimicrobial prophylaxis into the postoperative period is of no value in preventing infectious complications following thoracic surgery involving tube thoracostomy. Contemporary perioperative guidelines reflect the growing awareness that, for many operations, exposure to antibiotics postoperatively may be ineffective and increases the risk of adverse events. Procedures involving drainage of sterile body cavities such as the pleural space, however, appear to be qualitatively different. The idea of allowing foreign materials to communicate with the outside world unprotected by systemic antibiotics, particularly in the early postoperative period, provokes at least some anxiety among surgeons. These findings may reduce this anxiety and arguably expose the false solace of postoperative prophylaxis, at least in routine, elective cases involving chest tubes. Although the results are compelling, it is important to note that their study, conducted at a single institution, may not reflect real-world processes of care where preoperative prophylaxis is not consistently timely and antibiotic choice is not always appropriate, especially in areas of the world not exposed to value-based payment strategies such as the Surgical Care Improvement Project in the United States. In addition, the reader will take note of the short median time to chest tube removal and the short median length of hospital stay in comparison with those in published data from large data sets. Perhaps it is meticulous aerostasis during surgery and prompt chest tube removal that make postoperative antimicrobial prophylaxis irrelevant. If so, the findings in this study by Oxman and colleagues may not be immediately generalizable as long as real-world measures continue to fall short of those best practices exemplified by their study.
Remote sensing of precipitable water over the oceans from Nimbus 7 microwave measurements

Global maps of precipitable water over derived from scanning multichannel microwave radiometer (SMMR) data reveal salient features associated with ocean currents and the large scale general circulation in the atmosphere. Nimbus-7 SMMR brightness temperature measurements in the 21 and 18 GHz channels are used to sense the precipitable water in the atmospheric over oceans. The difference in the brightness temperature (T sub 21 -T sub 18), both in the horizontal and vertical polarization, is found to be essentially a function of the precipitable water in the atmosphere. An equation, based on the physical consideration of the radiative transfer in the microwave region, is developed to relate the precipitable water to (T sub 21 - T sub 18). It shows that the signal (T sub 21- T sub 18) does not suffer severely from the noise introduced by variations in the sea surface temperature, surface winds, and liquid water content in non rain clouds. The rms deviation between the estimated precipitable water from SMMR data and that given by the closely coincident ship radiosondes is about 0.25 g/ sq cm
COLORBLINDNESS AND MATHEMATICS

ABSTRACT You've just given a really nice explanation of a new mathematics topic to a student and it is apparent that little meaning has been conveyed. Is it possible that, in some sense, you are trying to help one who is colorblind see color? If so, what can be done? * Based on a presentation given at the Conference on the Teaching of Calculus held at Harvard University on 12–13 June 1992.
Time-dependent emergent intensity from an anisotropically-scattering semi-infinite atmosphere

Abstract The time-dependent emergent intensity for an arbitrarily anisotropically-scattering, semi-infinite medium is obtained in terms of the stationary collided intensities. A numerical example is presented for a Rayleigh scattering atmosphere.
Legal aspects of sinkhole development and flooding in karst terranes: 1. Review and synthesis

Structures built within the area of influence of a sinkhole can be affected by collapse, subsidence, or flooding. Unanticipated property losses may be involved, and litigation commonly ensues. Insurance compensation for damages that result from sinkhole collapse or subsidence in a karst terrane are covered by statute only in Florida and by voluntary agreement of companies operating in Tennessee Liability or insurance compensation for damages resulting from sinkhole flooding is not specifically covered by any state or federal statute. Regulations of the National Flood Insurance Program have been interpreted to allow coverage by this program for homes affected by sinkhole flooding in Bowling Green, Kentucky In the present article, case law, legal concepts of groundwater and surface water, liability, and law review articles relevant to sinkhole litigation are summarized The rationales of plaintiffs and defendants are reviewed Liability for damages have been based on allegations of negligence, breach of various water law doctrines, trespass, nuisance, loss of support, breach of contract, and implied warranty of habitability Defenses against these allegations have been based on the merits of each of them and oncaveat emptor Several alternative rationales for claiming liability for losses incurred because of sinkhole development or flooding are proposed and discussed. The little-knownHenderson v Wade Sand and Gravel is highly recommended as an alternative leading case that clearly and justifiably gives protection to adjacent landowners, and ties liability for damages caused by groundwater pumpage to nuisance law and related interference with property rights. Several little-known litigated cases of sinkhole development in response to groundwater pumpage will be summarized in a second article at a later date. Concepts of liability are evolving It can be expected that the professional geologist or engineer will have an increasing number of claims made against him or her which allege responsibility for sinkhole-related damages. Such damages can often be prevented by creative zoning, sound engineering, and better husbandry of land.
Evaluation of seismic noise for landmine detection system development

For several years a system has been under development at Georgia Tech that uses seismic surface waves to detect and image buried landmines. The details of this system have been previously reported in the literature. Current work involves the transition from a laboratory experimental system to a field-operable experimental system with the ultimate goal of creating an integrated field-operable prototype. Several issues have arisen in the transition to field testing. One of these is the nature and magnitude of the noise levels that limit system performance at field sites and the relevance of these for predicting noise that might be encountered in a realistic demining scenario. Noise introduced to the system sensor (a radar-based, non-contact displacement sensor) can arise from many sources (both natural and manmade). It may be received through a variety of mechanisms in addition to the sensor's primary transduction mechanism. Moreover, even noise which is received through the primary transduction mechanism need not involve purely seismic motion of the ground that is being interrogated. It might instead represent motion of the sensor's support structure or the purely local coupling of airborne noise into surface motion. To understand these effects, measurements have been made using ground contacting sensors at four field sites where other system-related measurements have also been made. The nature of the noise measurements has required that refinements be made to both the sensors themselves (triaxial geophones) and to the data acquisition system used for the measurement of the system’s seismic interrogation signals (a 12-bit, PC-based digitizer).
Antigen stimulated DNA and RNA synthesis in spleen cell suspensions from immunized rabbits.

SEVERAL metabolic inhibitors have been shown to inhibit the initiation of antibody synthesis in a variety of in vitro systems (see Table 1), and it has been suggested that certain of these agents may inhibit antibody formation by suppressing the formation of the messenger RNA which directs the synthesis of the antibody molecule, although other explanations have been considered3,4. In these studies the effect of the inhibitor was assessed after several days' incubation with the cells. Subsequent studies in which much shorter time periods were used have suggested that this may be the case5,6. It has been shown, however, that the antibody forming cell population arises by a rapid proliferation of a much smaller number of precursor cells, both in vivo7–9 and in vitro10–12, in both the primary and secondary response. It is clear that any agent which inhibits such proliferation will reduce the subsequent synthesis of antibody in experiments extended over longer periods of time. It is also probable that specific inhibitors of RNA and protein synthesis will subsequently affect DNA synthesis, providing the time of incubation with the drug is sufficiently prolonged. It was therefore of some interest to measure the concentration of a selected group of metabolic antagonists which would inhibit DNA, RNA and protein synthesis in an appropriate in vitro system. The results of such a study are recorded in Fig. 1.
Complete spectral assignments of cevadine and veratridine by 2D NMR techniques

The long-range CH correlation NMR experiment (with decoupling of modulation of intensities due to one-bond couplings during refocusing) and the double quantum coherence correlation spectroscopy (DQCOSY) experiment were used, together with the standard one-bond CH correlation and COSY spectra, for complete 13C and 1H spectral peak assignments of veratrine (a 2:1 mixture of cevadine and veratridine). The long-range CH correlation experiment determined the long-range CH connectivity network, thus indirectly providing carbon–carbon connectivity. The DQCOSY experiment proved to be a complementary technique to the standard COSY experiment in unraveling and/or confirming proton–proton connectivities in this highly crowded proton spectrum.
Beyond the mean: The role of variability in predicting ecological effects of stream temperature on salmon

Alterations in variance of riverine thermal regimes have been observed and are predicted with climate change and human development. We tested whether changes in daily or seasonal thermal variability, aside from changes in mean temperature, could have biological consequences by exposing Chinook salmon (Oncorhynchus tshawytscha) eggs to eight experimental thermal regimes. Thermal variance impacted both emergence timing and development at emergence. Further, genetics influenced the magnitude of that response. Ecological implications include: (1) changes in thermal variability, independent of warming, have the potential to alter the timing of life history processes, (2) the commonly-used degree day accumulation model is not sufficient to predict how organisms respond to altered temperature regimes, and (3) there are likely to be genetic differences in how individuals and populations respond to future water temperature regimes.
Conformationally restricted mimics of vitamin D rotamers

Abstract Drug developments in the vitamin D field have continued to focus on structure-function studies of analogs produced by chemically modifying the structure of 1α,25-dihydroxyvitamin D 3 (1,25-D3) and its metabolites. Direct structural information gleaned from X-ray crystallographic or NMR studies regarding the ligand-receptor complex and other guest-host systems, which are likely involved in initiating biologic responses, also offers potential insight into drug design. Evidence has accrued suggesting that topologically different conformers of 1,25-D3 may bind to proteins in different ways, including the induction of different conformations of protein. This paper concerns our progress on the chemical synthesis of analogs (e.g. ansa-steroids, suprasterols, vinylallenes and other analogs) conformationally locked or at least rotationally restricted to mimic higher energy conformers of 1,25-D3.
Isotope shift of 3 × 10 5 -yr 202 Pb in the 6p 2 ³P 0 −6p7s ³P1° 283.3-nm resonance line

The isotope shift in the 283.3-nm resonance line of mass-separated radioactive 202Pb was measured by absorption spectroscopy with the use of our 9.1-m focal-length Czerny–Turner spectrometer. The value of the shift, relative to 208Pb, is −208(3) × 10−3 cm−1. A signal-averaging scanning technique was used to record the spectrum. Isotonic comparisons with the relative isotope shifts in mercury and thallium indicate a possible effect on the isotope shift of the unpaired proton in thallium.
GIT1 Mediates VEGF-Induced Podosome Formation in Endothelial Cells Critical Role for PLCγ

Objective— We and others showed that tyrosine kinase receptors (TKRs) such as the epidermal growth factor receptor stimulate G protein-coupled receptor (GPCR) kinase-interacting protein 1 (GIT1) phosphorylation via c-Src, which is required for phospholipase C-γ (PLCγ) activation, indicating that GIT1 participates in TKR signaling. VEGF is the most important TKR in endothelial cells (ECs); essential for cell survival, migration, and angiogenesis. Podosomes, actin-rich structures, were found to contribute to EC migration, tissue invasion, and matrix remodeling, suggesting a role for podosomes in angiogenesis. Because GIT1 is a substrate of c-Src, and podosome formation is c-Src dependent, we hypothesized that GIT1 plays an important role in VEGF-induced EC podosome formation and cell migration. Methods and Results— Exposure of ECs to VEGF for 30 minutes stimulated GIT1 colocalization with podosomes. Depletion of GIT1 by siRNA significantly decreased VEGF-induced podosome formation. A key role for PLCγ was suggested by several experiments. Double staining PLCγ and actin showed colocalization of PLCγ with podosomes. Podosome formation was dramatically reduced by PLCγ inhibitor U73122, Src inhibitor PP2, or expression of dominant negative small GTPases. Therefore, VEGF-induced EC podosome formation is dependent on Src, GIT1, PLCγ, and small GTPases. In addition, matrix metalloprotease 2 (MMP2) and MT-MMP1 were detected at sites of VEGF-induced podosomes. Depletion of GIT1 by siRNA also significantly inhibited VEGF-induced MMP2 activation and extracellular matrix (ECM) degradation. Therefore, GIT1 mediates VEGF-induced matrix metalloproteinase (MMP) activation and ECM degradation by regulating podosome formation. Finally, depletion of GIT1 by siRNA significantly decreased VEGF-induced cell migration. Conclusions— These data indicate that GIT1 is an essential mediator for VEGF-induced EC podosome formation and cell migration via PLCγ.
Student learning in science simulations: Design features that promote learning gains

This research examines science-simulation software available for grades 6–12 science courses. The study presented, funded by the National Science Foundation, had two objectives: a literature synthesis and a product review. The literature synthesis examines research findings on grade 6–12 student learning gains and losses using virtual laboratories and science-simulation software, derived from a review of 79 relevant studies identified. Based on that literature, significant aspects of how such products influence student learning are identified. Tables summarize the research-based evidence about best practices in instructional design for such virtual lab and simulation products. Some products were then reviewed as case studies to determine in what ways and to what extent they implement such research-identified best practices. The overall goal was to consider where the most progress is being made in effective virtual-lab and simulation products, and what directions future development should take. The intent is to inform science educators, teachers, administrators, and policy makers who are using, buying, and examining middle and high school instructional materials. © 2011 Wiley Periodicals, Inc. J Res Sci Teach 48: 1050–1078, 2011