cssi/SciSciGPT-SciSciNet huggingface dataset:
Investigating the Value of History in the Preparation of Teachers

Educational foundations courses that incorporate the study of history make implicit and explicit claims about what the study of the past can achieve for prospective teachers. This article shows how a seminar investigation of one educational foundations course spurred rich debate and generated new conceptual ideas about how to better communicate the complex historiographical problems inherent with using the time-bound and place-bound events of the past to understand the present or predict an unknown future.
Acyl hydrazines as precursors to acyl radicals

Abstract The use of acyl hydrazines (hydrazides) as precursors for the stoichiometric generation of acyl radicals is explored. Two classes of substrates are examined: unsubstituted acyl hydrazines and acyl hydrazines substituted with a leaving group (2-nitrobenzenesulfonyl or ‘nosyl’). Both types are successfully converted to acyl radicals, and are then trapped by nitroxide radicals to give acyloxyamine products. Cyclization reactions are demonstrated for both classes of substrates. A low temperature modification of the McFayden–Stevens reaction is also developed.
Maritally Aggressive Men: Angry, Egocentric, Impulsive, and/or Biased

This research explored the relationships between the language that 86 married men used to describe their marriages, other personal characteristics of the men, and the men’s wife-directed aggression. Methods included linguistic inquiry word count analysis, temperament measures, an empathic accuracy-type paradigm, and signal detection analysis. Husbands’ use of anger words and egocentric words in describing their marriages, along with husbands’ impulsivity, critical/rejecting overattribution bias, and attentional disorder/ impairment predicted the men’s wife-directed aggression. Multiple regression and moderation analyses revealed that men’s use of anger words and first-person pronouns in describing their own marriages were unique predictors of their wife-directed aggression. Also, men’s critical/rejecting overattribution bias and impulsivity interacted to predict the men’s wife-directed aggression. Results are discussed in terms different wife-abuser subtypes and their implications for the treatment of agg...
Inhaled Nitric Oxide and Inhaled Prostacyclin in Acute Respiratory Distress Syndrome: What is the Evidence?

The mortality for acute respiratory distress syndrome remains unacceptably high. Two vasodilators, inhaled prostacyclin and inhaled nitric oxide, are reviewed in this article. Knowledge of inhaled prostacyclin has grown substantially in the past 30 years, but less research exists about its utility in acute respiratory distress syndrome. Inhaled prostacyclin and other prostaglandin derivatives are used in acute respiratory distress syndrome with increasing frequency. Currently, only randomized controlled trials exist for inhaled nitric oxide in acute respiratory distress syndrome patients. Randomized controlled trials with consistent dosing methods are needed for both vasodilators to better define their role in the treatment of acute respiratory distress syndrome.
Feature detection and orientation tuning in the Drosophila central complex

Many animals, including insects, are known to use visual landmarks to orient in their environment. In Drosophila melanogaster, behavioural genetics studies have identified a higher brain structure called the central complex as being required for the fly's innate responses to vertical visual features and its short- and long-term memory for visual patterns. But whether and how neurons of the fly central complex represent visual features are unknown. Here we use two-photon calcium imaging in head-fixed walking and flying flies to probe visuomotor responses of ring neurons--a class of central complex neurons that have been implicated in landmark-driven spatial memory in walking flies and memory for visual patterns in tethered flying flies. We show that dendrites of ring neurons are visually responsive and arranged retinotopically. Ring neuron receptive fields comprise both excitatory and inhibitory subfields, resembling those of simple cells in the mammalian primary visual cortex. Ring neurons show strong and, in some cases, direction-selective orientation tuning, with a notable preference for vertically oriented features similar to those that evoke innate responses in flies. Visual responses were diminished during flight, but, in contrast with the hypothesized role of the central complex in the control of locomotion, not modulated during walking. Taken together, these results indicate that ring neurons represent behaviourally relevant visual features in the fly's environment, enabling downstream central complex circuits to produce appropriate motor commands. More broadly, this study opens the door to mechanistic investigations of circuit computations underlying visually guided action selection in the Drosophila central complex.
Relationship between Snow Extent and Midlatitude Disturbance Centers

AbstractA relationship between midlatitude cyclone (MLC) tracks and snow-cover extent has been discussed in the literature over the last 50 years but not explicitly analyzed with high-resolution and long-term observations of both. Large-scale modeling studies have hinted that areas near the edge of the snow extent support enhanced baroclinicity because of differences in surface albedo and moisture fluxes. In this study, the relationship between snow-cover extent and midlatitude disturbance (MLD) trajectories is investigated across North America using objectively analyzed midlatitude disturbance trajectories and snow-cover extent from the North American Regional Reanalysis (NARR) for 1979–2010. MLDs include low-level mesoscale disturbances through midlatitude cyclones. A high-resolution MLD database is developed from sea level pressure minima that are tracked through subsequent 3-h time steps, and a simple algorithm is developed that identified the southern edge of the snow-cover extent. A robust enhanced ...
Relating the skill of tropical cyclone intensity forecasts to the synoptic environment

AbstractPrior knowledge of the performance of a tropical cyclone intensity forecast holds the potential to increase the value of forecasts for end users. The values of certain dynamical parameters, such as storm speed, latitude, current intensity, potential intensity, wind shear magnitude, and direction of the shear vector, are shown to be related to the error of an individual model forecast. The varying success of each model in the different environmental conditions represents a source of additional information on the reliability of an individual forecast beyond average forecast error.Three hurricane intensity models that were operational for the duration of the five hurricane seasons between 2006 and 2010, as well as the National Hurricane Center official forecast (OFCL), are evaluated for 24-, 48-, and 72-h forecasts in the Atlantic Ocean. The performance of each model is assessed by computing the mean absolute error, bias, and percent skill relative to a benchmark model. The synoptic variables are bin...
Determination of atmospheric lead-210 by alpha-scintillation counting of air filters

Alpha-counting of filters used to sample large volumes of air provides a convenient way of determining atmospheric concentrations of210Pb. Following decay of short-lived222Rn and220Rn progeny, alpha activity of the filters increases as210Pb decays to210Po. After transient equilibrium is reached at about 3 y, alpha activity diminishes with the 22.3 y halflife of210Pb. The degree of equilibrium between210Pb and210Po can be calculated subsequent to sampling, and the average concentration of210Pb in the air during the sampling period can be computed. Contributions to the total210Pb from ambient short-lived radon progeny are small, typically 2–4%. Using high volume air samplers with collection rates of 1.1–1.7 m3/min for 24 h periods, and using counting times of 2 h for 20 cm2 filter sections, we measured alpha counts ranging from 0.0100±0.0050 to 0.200±0.0200 dps. Periodic measurements on 100 of these filters over a 4 y period yielded mean210Pb levels with standard deviations less than ±15%. The method requires minimal sample preparation and can be used to determine past atmospheric210Pb concentrations on filters stored for up to 20 y and more.
La Conquistadora: A Conquering Virgin Meets Her Match

‭The Mexican Museum in San Francisco commissioned Delilah Montoya to produce a contemporary codex for the 1992 exhibition “The Chicano Codices: Encountering Art of the Americas,” which sought to critique Quincentennial observances erasing indigenous presence. The artist created a seven-page book, Codex Delilah, Six-Deer: Journey from Mexicatl to Chicana, that depicted the consequences of the initial American-European encounter, and she used the heroine Six-Deer to visually record women’s contributions to this 500-year history. In the codex’s fourth panel, Six-Deer comes across Adora-la-Conquistadora, the artist’s revisioning of the New Mexican Catholic icon of Our Lady of the Rosary, La Conquistadora, the oldest figure of Marian devotion in the United States. Six-Deer contests the designs of the Virgin, who intends to forcefully convert the native peoples of New Mexico. Rather than capitulate, Six-Deer refuses to participate in New Mexico’s Reconquista of 1692. Although Montoya appropriated La Conquistadora’s traditional sartorial splendor, she proposed an alternate reading of this Conquering Virgin. This article reads Montoya’s depiction within the dimensions of La Conquistadora’s historical, religious, cultural, and iconographic contexts.‬
Placental Blood Flow and the Risk of Preterm Delivery

The goal of this analysis was to estimate the influence of variation in uterine artery and umbilical artery resistance indices (RIs) measured across gestation on variation in the risk of preterm delivery (PTD). Analyses were carried out on data collected in a longitudinal study of 523 gravidas. Uterine and umbilical artery RIs were measured on three occasions during pregnancy (16-20 weeks gestation; 21-29 weeks gestation; and 30-36 weeks gestation). Data were analyzed using the Cox proportional hazards regression model. The primary outcome variable was birth prior to 37 weeks gestation. We found that for mothers who delivered preterm the mean uterine artery RI was consistently larger across all gestational ages, while the mean umbilical artery RI decreased significantly more slowly across gestation than for their term counterparts. In analyses pooled by type of delivery, we found that the hazard ratio (HR) for PTD was statistically significant for either uterine artery RI (HR=2.26, 95% CI: 1.65, 3.11) or umbilical artery RI (HR=3.47, 95% CI: 2.43, 4.95) after adjusting for statistically significant covariates. In stratified analyses, the hazard ratio for PTD was also positively associated with an increased uterine or umbilical artery RI in both spontaneous and indicated deliveries. Our data suggest that pregnancies with either a higher uterine or umbilical artery RI across gestation are more likely to be affected by PTD suggesting that disordered placentation resulting in compromised placental blood flow may be an important pathway to PTD.
Recent Chemotherapy Reduces the Sensitivity of [18F]Fluorodeoxyglucose Positron Emission Tomography in the Detection of Colorectal Metastases

Purpose [18F]2-fluoro-2-deoxyglucose (FDG) –positron emission tomography (PET) has become a useful tool in the assessment of patients with colorectal cancer. Patients often undergo chemotherapy as treatment for primary or metastatic colorectal malignancy. Because cytotoxic chemotherapy may decrease the cellular metabolic activity of tumor, we assessed the effects of chemotherapy on PET imaging. Patients and Methods This is a prospective study examining detection of hepatic colorectal metastases by FDG-PET as related to use of chemotherapy. Pathologic analysis of the liver resection specimens was used as gold standard. Results There was significantly decreased tumor FDG uptake (as measured by the maximal standardized uptake value) in patients treated preoperatively with chemotherapy, resulting in less efficient detection of cancerous lesions. One biologic basis of this change in accuracy of PET was a significant decrease in the activity of the key glycolytic enzyme hexokinase in tumors from patients treate...
Experimental investigation of the vorticity generation within a spilling water wave

Sources of vorticity are examined for a laboratory-generated spilling breaking wave. Two cases are studied. For the first case, based on the breaker height, the Reynolds and Froude numbers are 7370 and 2.04, respectively. The breaker is preceded by 1 mm wavelength capillary waves, with the largest amplitude-to-wavelength ratio equal to 0.18. For this case, it is found that the dominant source of vorticity flux is a viscous process, due to the deceleration of a thin layer of the surface fluid. For the second case, the Reynolds and Froude numbers based on the wave height are 1050 and 1.62, respectively. No breaking is observed for this case; rather a capillary–gravity wave is observed with 4 mm wavelength capillaries preceding the gravity wave. The largest amplitude-to-wavelength ratio of these capillaries is 0.28. This case shows that capillary waves do not contribute to the vorticity flux; rather the only dominant source of the vorticity flux into the flow is the free-surface fluid deceleration. Lastly, a thin free-surface jet that is relatively vorticity-free is found to precede the spilling breaker. Analyses suggest that our wave-breaking phenomena can be modelled by a hydraulic jump phenomenon where the Froude number is based on the thickness of the free-surface jet, and on the velocity of the free-surface jet just prior to breaking. We believe this to be a more physically descriptive value of the Froude number. For the high-speed case, the Froude number based on the thickness of the free-surface jet is 4.78, while for the lower-speed case it is 2.14.
X-Ray and EUV Spectra of Solar Flares and Laboratory Plasmas

Recent laboratory work relevant to solar flares on the spectroscopy of highly ionized atoms is reviewed. Much of this work has concerned the X-ray and EUV spectrum of iron ions, Fe xviii–Fe xxiv, which produce prominent emission lines in the spectra of solar flares. Also discussed are recently obtained laboratory X-ray spectra of emission lines of hydrogen-like and helium-like ions, and associated satellite lines due to transitions of the type,1s2l–2p2l, 1s 22l–1s2p2l,and 1s 22l–1s2l3p.Satellite lines have also been identified in spectra of solar flares, and can be used to determine the electron temperature of the plasma. The laboratory work is important in the planning of future experiments in solar flare X-ray and EUV spectroscopy.
Digoxin therapy and associated clinical outcomes in the MADIT-CRT trial

Background Digoxin's pharmacological, hemodynamic, and electrophysiological properties are well understood. However, in modern heart failure (HF) treatment, its effect has yet to be fully investigated. Objective The aim of the present study was to determine the effects of digoxin on outcomes in patients with mild HF implanted with an implantable cardioverter-defibrillator (ICD) or cardiac resynchronization therapy with defibrillator (CRT-D) device. Methods We investigated the effect of digoxin treatment on the end points of HF/death, HF alone, death alone, and ventricular tachycardia or ventricular fibrillation (VT/VF) in 1820 patients with mild HF (New York Heart Association class I and II), prolonged QRS duration (≥130 ms), and reduced left ventricular ejection fraction (≤30%) enrolled in the Multicenter Automatic Defibrillator Implantation Trial – Cardiac Resynchronization Therapy trial. Multivariate Cox proportional hazards regression models were used to determine the effect of time-dependent digoxin usage on the end points. Results Digoxin therapy was not associated with an increased or decreased risk of HF/death (hazard ratio [HR] 1.07; 95% confidence interval [CI] 0.86–1.33; P = .0.56), HF alone (HR 1.1.04; 95% CI 0.82–1.32; P = .76), or death alone (HR 0.93; 95% CI 0.67–1.32; P = .71). However, digoxin was associated with a significant 41% increased risk of VT/VF (HR 1.41; 95% CI 1.14–1.75; P = .002), which was driven by a significantly increased risk of VT/VF with heart rate ≥200 beats/min (HR 1.65; 95% CI 1.27–2.15; P ≤ .001), whereas no increased risk of VT/VF with heart rate P = .19). No significant differences in digoxin's effect on any of the end points were found between patients with ICD and patients with CRT-D (interaction P > .5). Conclusion The use of digoxin in patients with mild HF implanted with an ICD or CRT-D device was not associated with reductions in HF/death events. However, digoxin therapy was associated with an increased risk of high-rate VT/VF (≥200 beats/min).
A nonparametric test for bivariate symmetry

Abstract : The paper introduces a conditionally distribution-free test of bivariate symmetry based on the sample distribution function. The test is shown to be consistent against a wide class of alternatives. In particular, if the underlying bivariate distribution is absolutely continuous, then the test is consistent against all alternatives to the null hypothesis. Power comparisons of the conditional test, a normal theory test devised by Bell and Haller, and the Wilcoxon signed rank test, are given for bivariate normal and bivariate exponential populations. (Author)
Adaptive multiresolution filtering to forecast nonlinear time series

There are two ways to improve the identification process of a dynamic system using an artificial neural network: 1) preprocessing the training values to extract characteristics of the data; and 2) adapting the architecture of the network. In this paper we used an adaptive scheme of multiresolution filtering to decompose the series into other series for an easier analysis. The scheme proposed uses genetic algorithm to find the optimal bank of filters without previous knowledge of the behavior of the system to be identified. A new variation of the algorithm using random individuals is proposed to avoid local minima. The objective function proposed is the estimation quadratic error of a multilayer perceptron using the Levenberg-Maquardt learning.
Characterization of anti-channel catfish MHC class IIβ monoclonal antibodies

This study characterizes four monoclonal antibodies (mAb) developed against the major histocompatibility complex (MHC) class II beta chain of the channel catfish, Ictalurus punctatus. Immunoprecipitations using catfish clonal B cells revealed that each of these mAbs immunoselected proteins of approximately 32 and 36 kD, which are of the appropriate sizes for MHC class II alpha and beta chains, respectively. Cell distribution studies using a fluorescence-activated cell sorter (FACS) combined with RT-PCR analyses demonstrated that MHC class II beta is expressed at a high density on catfish clonal macrophage, B and T cell lines, on alloantigen stimulated leukocytes, and on lipopolysaccharide-induced B-cell blasts. Collectively, these results demonstrate the potential importance of these antibodies as reagents in future studies dealing with the functional role of MHC class II molecules in immune recognition of self from non-self.
A PCR-based platform for microRNA expression profiling studies

MicroRNAs (miRNAs) are newly identified small noncoding RNA molecules that play important regulatory roles in many biological processes. Changes in miRNA expression are associated with a variety of normal physiological processes as well as with human diseases including cancer. Thus, one important way to characterize miRNA function is to identify changes in miRNA expression profiles. To date, microarrays are the most widely used technique for miRNA expression profiling analysis. However, there are major limitations when microarrays are applied to miRNA profiling studies. Here we report a new PCR-based assay platform for miRNA expression profiling analysis. The primers associated with these miRNA assays were designed using a novel bioinformatics algorithm that has incorporated many primer selection features for improved assay specificity, sensitivity, and homogeneity. The primer design algorithm has been extensively validated experimentally and has been shown to have robust performance for the measurement of miRNA expression in a variety of biological samples at a low cost.
Depression of reticuloendothelial system phagocytic function by ingested lipids.

SummaryThe oral administration of digestible lipids was followed by prolonged depression of reticuloendothelial system phagocytosis as measured by blood clearance of colloidal carbon. In contrast to the effects of intravenously administered lipids oral trioleate was as effective a depressant as ethyl stearate.
Man versus machine: what's the standard?

At 2:45 pm on Thursday, May 6, 2010, the Dow Jones Industrial Average was already down 3.9% on fears that the Greek economy was in free-fall. Suddenly, in 5 minutes, the index plunged 573 points. Less than 2 minutes later, the Dow had rocketed back up 543 points, going on to finish the day down 3.2
Preoperative computed tomography measurements of pancreatic steatosis and visceral fat: prognostic markers for dissemination and lethality of pancreatic adenocarcinoma

hpb_304 404..410 Background: Increased visceral fat and pancreatic steatosis promote lymphatic metastases and decreased survival in patients with pancreatic adenocarcinoma after pancreatoduodenectomy (PD). Objectives: We aim to determine the utility of preoperative computed tomography (CT) measurements of pancreatic steatosis and visceral fat as prognostic indicators in patients with pancreatic adenocarcinoma. Methods: High-resolution CT scans of 42 patients undergoing PD for pancreatic adenocarcinoma were reviewed. Attenuation in CT of the pancreas, liver and spleen were measured in Hounsfield units and scored by two blinded investigators. Perirenal adipose tissue was measured in mm. Results: Lymphatic metastases were present in 57% of patients. Age, gender, tumour size and margin status were similar in patients with and without nodal metastases. Node-positive patients had increased visceral but not subcutaneous fat pads compared with node-negative patients and decreased CT attenuation of the pancreatic body and tail and liver. Node-positive patients stratified by visceral adiposity (10 mm vs. <10 mm) demonstrated poorer survival (7 1 months vs. 16 2 months; P < 0.01). Conclusions: In resected pancreatic adenocarcinoma, increased pancreatic steatosis and increased visceral fat stores are associated with lymphatic metastases. Furthermore, increased visceral fat is associated with abbreviated survival in patients with lymphatic metastases. Hence, increased visceral fat may be a causative factor of abbreviated survival and serves a prognostic role in patients with pancreatic malignancies.
Optimization of the ArctiCooler for lowest thermal resistance in a minimum volume

The trends in processor power are increasing at an alarming rate with each generation of processor as clock speeds are being pushed beyond 1 GHz. Processor power is predicted to reach the 200 watt level in the next 3 to 5 years. This may have a severe impact on architecture of future systems, especially desktop machines that must operate quietly in the office or home environment. The ArctiCooler was developed by Hewlett-Packard just for this purpose; to cool high-power processors at minimal noise levels. This paper describes the steps taken to optimize the ArctiCooler (alias TurboCooler) to achieve the lowest thermal resistance possible in a minimum volume.
Constitutive Modeling of a Thermoplastic Olefin Over a Broad Range of Strain Rates

A microstructually motivated, three-dimensional, large deformation, strain rate dependent constitutive model has been developed for a semi-crystalline, blended, thermoplastic olefin (TPO) (Wang, Y, 2002, Ph.D. thesis, The University of Michigan, Ann Arbor, MI). Various experiments have been conducted to characterize the TPO and to verify the modeling approach (Wang, Y., 2002, Ph.D. thesis, The University of Michigan, Ann Arbor, MI). The model includes a quantitative rate-dependent Young's modulus, a nonlinear viscoelastic response between initial linear elastic response and yield due to inherent microstructural irregularity, rate and temperature dependent yield with two distinctive yield mechanisms for low and high strain rates, temperature-dependent strain hardening, plastic deformation of crystalline regions, and adiabatic heating. It has been shown to accurately capture the observed TPO stress-strain behavior including the rate-dependent initial linear elastic response; temperature, strain rate, and deformation state-dependent yield; temperature and deformation state-dependent strain hardening; and pronounced thermal softening effects at high (impact) strain rates. The model has also been examined for its ability to predict the response in plane strain compression based on material parameters chosen to capture the uniaxial compression response. The model is predictive of the initial strain rate dependent stiffness, yield, and strain hardening responses in plane strain. Such predictive capability demonstrates the versatility with which this model captures the three-dimensional anisotropic nature of TPO stress-strain behavior.
Ingestibility, digestibility, and engineered biological control potential of Flavobacterium hibernum, isolated from larval mosquito habitats.

Flavobacterium hibernum, isolated from larval habitats of the eastern tree hole mosquito, A. triseriatus, remained suspended in the larval feeding zone much longer (8 days) than other bacteria. Autofluorescent protein markers were developed for the labeling of F. hibernum with a strong flavobacterial expression system. Green fluorescent protein (GFP)-tagged F. hibernum cells were quickly consumed by larval mosquitoes at an ingestion rate of 9.5 × 104/larva/h. The ingested F. hibernum cells were observed mostly in the foregut and midgut and rarely in the hindgut, suggesting that cells were digested and did not pass the gut viably. The NanoLuc luciferase reporter system was validated for quantitative larval ingestion rate and bacterial fate analyses. Larvae digested 1.87 × 105 cells/larva/h, and few F. hibernum cells were excreted intact. Expression of the GFP::Cry11A fusion protein with the P20 chaperone protein from Bacillus thuringiensis H-14 was successfully achieved in F. hibernum. Whole-cell bioassays of recombinant F. hibernum exhibited high larvicidal activity against A. triseriatus in microplates and in microcosms simulating tree holes. F. hibernum cells persisted in microcosms at 100, 59, 30, and 10% of the initial densities at days 1, 2, 3, and 6, respectively, when larvae were absent, while larvae consumed nearly all of the F. hibernum cells within 3 days of their addition to microcosms.
Optimal synthesis of application specific heterogeneous pipelined multiprocessors

We present a technique and formal model for optimal synthesis of specialized heterogeneous multiprocessors, given task flow graphs to be executed in a pipelined (periodic) fashion. SOS is a formal approach to system synthesis using mixed integer-linear programming, ensuring optimally of the final solutions. SOS was extended to cover the pipelined design style. The extensions were made while trying to avoid a considerable increase in computation time over the non-pipelined case. The extensions include new binary variables as well as new constraints used to ensure numerical convergence. The present tool supports minimization of parameters such as initiation rate, latency and cost. >
Lipid-lowering drugs. An overview of indications and optimum therapeutic use.

Drug treatment of patients with hyperlipoproteinaemia is indicated to reduce the risk of atherosclerosis in patients with increased concentrations of atherogenic lipoproteins, and to lower the plasma concentrations of triglyceride-rich lipoproteins in patients with severe hypertriglyceridaemia who are at risk of abdominal pain and pancreatitis. Such therapy should be initiated only after satisfactory exclusion of secondary causes of hyperlipoproteinaemia, and should be regarded as an adjunct to rather than a substitute for appropriate dietary therapy. Drug therapy should be strongly considered in those patients with concentrations of atherogenic lipoproteins which exceed the 90th to 95th percentile for age. In patients with increased plasma concentrations of low density lipoproteins (LDL), agents which enhance the rate of LDL catabolism (cholestyramine and colestipol) or reduce the rate of LDL synthesis [e.g. nicotinic acid (niacin)] are the 'drugs of choice'. For those patients with concurrent hypertriglyceridaemia, nicotinic acid is the preferred initial drug, and in both patient groups combined drug therapy is often necessary to attain optimal reductions in LDL cholesterol concentrations. Clofibrate remains the 'drug of choice' for the rare patient with type III hyperlipoproteinaemia, whereas the newer agent gemfibrozil should be used in patients with plasma triglyceride concentrations above 1000 mg/dl who are at increased risk of abdominal pain and pancreatitis. Although currently limited to investigational use, mevinolin and related compounds, which are specific inhibitors of the rate-limiting enzyme in cholesterol biosynthesis (HMG Co-A reductase), offer considerable promise in the therapy of patients with primary hypercholesterolaemia due to elevated levels of LDL cholesterol.
Efficient survey sampling of households via Gaussian quadrature

Summary. The collection of data through surveys is a costly and time-consuming process, particularly when complex economic data are involved. The paper presents an efficient approach, based on Gaussian quadrature, to survey sampling when some information is available about the target population. Using household data from Mozambique, we demonstrate that Gaussian quadrature subsamples, based on relatively easy to observe household characteristics such as size and educational attainment of members, generate better estimates of the moments of
The Effectiveness Of Internal And External Mechanisms Of Corporate Control

This research reflects a recent trend toward the development of an overall understanding of corporate control. Previous research has examined CEO turnover and corporate takeovers separately. This research provides a more complete analysis of the corporate control of the firm conditioned on previous events over the period 1978 - 1988. Logistic regression analyses indicate that the probability of a takeover offer is highest for firms performing poorly which have not previously replaced their CEO. Debt, the percentages of stock held by the ceo or outside investor, and the existence of an antitakeover mechanism also affect the probability of a firm receiving a takeover offer. Results support the theory that external corporate control mechanisms do function when internal mechanisms have failed to function. Additionally, results suggest the external labor market is working to attract the CEO of a firm performing well.
The Effect of Alterations in Haematocrit on Tumour Sensitivity to X-rays

Hypoxic cells in human tumours probably contribute to the failure of radiotherapy in some sites. Changes in the oxygen carrying capacity of the blood, such as in anaemia, have been shown to influence tumour response. The effect of acute and chronic changes in haematocrit on the radiosensitivity of three mouse tumours (EMT6, KHT and RIF-1) were studied. Alterations in haematocrit were achieved by bleeding followed by retransfusion. When radiation was preceded immediately by an acute reduction in haematocrit (anaemia), radiosensitivity was markedly reduced in each tumour. An acute rise in haematocrit (polycythaemia) increased or decreased X-ray sensitivity depending on its severity. The optimum haematocrit for maximum sensitivity was always found to be at a level 5-10 per cent above normal. When the time between induction of anaemia and irradiation was increased, simulating a progressively longer duration of anaemia, marked changes in radiosensitivity of all the tumours were observed. A short duration of anaemia resulted in a resistant tumour with each cell line, but the resistance was gradually lost as the anaemia was prolonged, even though no recovery in haematocrit occurred. The rate of recovery to normal radiosensitivity varied from 24 to 72 hours in the different tumours. Therefore, only haematocrit changes which occurred within 1-3 days of a dose of radiation affect the radiosensitivity of these tumours.
Use it or Share it: Unlocking the Vast Wasteland of Fallow Spectrum

This paper suggests a general approach to authorizing and encouraging the utilization of otherwise wasted spectrum capacity: Use it or share it. The Federal Communication Commission and Obama Administration propose to meet exponential growth in mobile data demand by reallocating 500 MHz over 10 years. But while policymakers are focused almost entirely on auctions, there is a looming limit to the amount of spectrum below 3.7 GHz that can be reallocated for exclusively licensed commercial use. In contrast, there is substantially more unused and underutilized spectrum in Federal and some other bands where it is either not practical to relocate incumbent users or where that will take many years. Longer term, more dynamic sharing of unused or underutilized bands will be essential – a shift that will expand capacity and facilitate multi-band wireless networks characterized by far greater spectrum re-use close to the end user. Both spectrum re-use and backhaul will increasingly be more cost-effective at the edge of the network, closest to end-users and subject to their control (or, more practically speaking, determined on the fly by software in their device). Unused spectrum capacity can be made available more rapidly by developing more explicit band-by-band conditions for opportunistic access on a secondary basis that ensure primary users protection from harmful interference. A variety of “smart radio” technologies (e.g., sensing, dynamic frequency selection, software defined radios) and spectrum management tools (e.g., geolocation databases) will support dynamic spectrum access and shared use of a far larger number of underutilized bands, each with its own tailored use restrictions to minimize the risk of harmful interference to incumbents. The most promising mechanism for governing conditional access to underutilized bands are the geolocation databases the FCC will soon certify to manage unlicensed use of “white space” channels across the nation’s 210 local TV markets. If a frequency band is not being used at particular locations, time segments, altitudes, or angles of reception, then that currently wasted spectrum capacity could at a minimum be listed in the Database for opportunistic access, subject to whatever power limits, geographic exclusions and other conditions are necessary to avoid harmful interference to primary users or licensees. Device makers and service providers would simply choose from an expanded Database the combination of frequencies most appropriate to their needs. Three categories of spectrum should be prioritized for shared access: (1) FCC-held spectrum; (2) Federal bands that NTIA has determined cannot be cleared within 5 years for reallocation by auction; (3) fallow spectrum on licensed bands that have not been built out in substantial portions of the country. Bands opened for dynamic access can be unlicensed, leased, lightly-licensed or subject to user fees or micro-payments as appropriate.
Credit Default Swaps: A Cash Flow Analysis

Credit default swap (CDS) contracts are often considered synthetic versions of obligors’ bonds funded at LIBOR.Accordingly, in the absence of financial frictions and market segmentation, an obligor’s bond yield spread to LIBOR and its CDS premium at the same maturity should be zero.That analogy also underlies the consistent application of riskneutral pricing theory to both bonds and CDS.The authors describe difficulties in replicating a bond synthetically in the CDS, interest-rate swap, and repo markets and demonstrate that risk-neutral pricing theory implies different premiums for default protection on two bonds of the same maturity from the same obligor but having different coupons. They introduce a method for calculating CDS premiums and contingent payments under physical (i.e., actuarial) measure. The model derives physical probabilities from a combination of model-based estimates and historical values, and these are used to specify expected cash flows on CDS premium and default-contingent legs.The expected cash flows are then discounted at risk-free rates. The authors use this method to derive CDS premiums necessary to compensate for default and designate resulting excess market spreads as CDS risk premiums. They observe that, for certain historical periods, market CDS spreads were insufficient to compensate sellers of protection for expected payouts from default.
Intracranial Pressure Changes from a Temporal Lobe Mass in Cats

Temporal lobe mass lesions may result in neurologic deterioration in the absence of elevated intracranial pressure. One possible mechanism is direct compression of the midbrain by the enlarged temporal lobe. We have attempted to study such a mechanism in an animal model by creating an expanding left temporal lobe mass while measuring pressures within the left temporal lobe, midbrain, and either the right frontal lobe or right lateral ventricle.
Hollow Fiber Adsorbents for CO2 Removal from Flue Gas

The nation’s pulverized coal infrastructure is aging, and implementation of current retrofit postcombustion capture methods is extremely expensive. This paper describes a technology based on hollow...
Magnetic Properties of Mn 3 O 4 and the Canted Spin Problem

The magnetic properties of single crystals of hausmannite (${\mathrm{Mn}}_{3}$${\mathrm{O}}_{4}$) have been investigated between 4.2\ifmmode^\circ\else\textdegree\fi{}K and the ferrimagnetic Curie point at 41.9\ifmmode^\circ\else\textdegree\fi{}K. The $c$ axis was found to be the hard direction of magnetization and the $c$ plane was found to possess considerable anisotropy, with respective anisotropy fields of about ${10}^{5}$ oe and ${10}^{4}$ oe. These anisotropy energies decreased slowly with increasing temperature, whereas the coercive force at 15\ifmmode^\circ\else\textdegree\fi{}K was about an order of magnitude less than at 4.2\ifmmode^\circ\else\textdegree\fi{}K. The spontaneous magnetization is 1.85 ${\mathrm{\ensuremath{\mu}}}_{\mathit{B}}$/molecule, which agrees with previous polycrystalline values when the observed anisotropies are taken into account. However, several of the observed properties of hausmannite disagree, some quantitatively and others qualitatively, with calculations based on the Yafet-Kittel theory. It is concluded that the concept of canted spins is essentially correct, but that the specific Yafet-Kittel model involves oversimplifications which limit its applicability.
Risk of hemorrhage in patients over age 60 with arteriovenous malformations (AVMs)

Treatment selection for patients 60years of age and older with intracranial arteriovenous malformations (AVMs), requires careful consideration of the natural history and post-treatment hemorrhagic risk. We aimed to directly compare the natural history of AVMs with post-treatment hemorrhagic risk in this population. We retrospectively reviewed our AVM database of 683 patients. Patients ⩾60years at diagnosis were included. Treatment modality was divided into four groups: surgery±embolization (SE), radiosurgery±embolization (RE), embolization only (Emb), and observation (Obs). The natural history of the AVM was defined as the annual risk of hemorrhage under observation. Risk of hemorrhage after treatment was also calculated. Sixty-one patients with complete data were included. Average age was 68.4±7.5years, with 55.7% (n=34) being male. Twenty-seven (44.3%) patients presented with intracerebral hemorrhage (ICH). At last follow-up, modified Rankin Scale was higher in patients with subsequent hemorrhages (p=0.023). Overall, obliteration was 65.5%, with 100.0% in the SE group and 43.8% in the RE group (p<0.001). During an average follow-up period of 2.8±3.2years, six patients (9.8%) experienced hemorrhage, with two (12.5%) in the RE group, three (9.4%) in the Obs group and one (9.1%) in the SE group, corresponding to a natural history of 3.5% annual hemorrhage rate and a post-treatment hemorrhagic risk of 3.6%. This post-treatment hemorrhage risk was 2.4% in the SE group and 4.9% in the RE group. Presenting with ICH (p=0.042) and race (p=0.014) were associated with a higher risk of follow-up hemorrhage. Definitive treatment for AVM patients ⩾60years should be cautiously considered. Despite higher post-treatment obliteration rates, the subsequent hemorrhagic risk may exceed that of its natural history. For AVMs with a high risk for hemorrhage, surgery reduces hemorrhagic risk and achieves the highest rate of obliteration.
Performance of a simulated QPSK TDMA radio link with analog FM interference

A software simulation of a QPSK TDMA radio link subject to interference from analog FM mobile radio is described. Log-normal shadowing and multipath fading are simulated by superposing a finite number of random paths. The channel impulse response h(t) is assumed to be finite and constant for the duration of a transmission burst. A recursive algorithm is used to estimate h(t) for each burst, in order to reduce the intersymbol interference (ISI) due to the delay spread. Block coding, interleaving, and error correction are simulated. The results of the simulation are used to estimate the sensitivity of the overall bit error probability P/sub b/(SIR) to changes in the signal-to-interference ratio (SIR). >
Quantitative imaging analysis of transcanal endoscopic Infracochlear approach to the internal auditory canal.

Abstract Purpose A transcanal endoscopic infracochlear surgical approach to the internal auditory canal (IAC) in a human temporal bone model has previously been described. However, the proportion of patients with favorable anatomy for this novel surgical technique remains unknown. Herein, we perform a quantitative analysis of the transcanal endoscopic infracochlear corridor to the IAC based on computed tomography. Materials and methods High resolution computed tomography scans of adult temporal bones were measured to determine the accessibility of the IAC when using an endoscopic transcanal, cochlear-sparing surgical corridor. Results This approach to the IAC was feasible in 92% (35 of 38) specimens based on a minimum distance of 3 mm between the basilar turn of the cochlear and the great vessels (jugular bulb and carotid artery). Conclusions Infracochlear access to the IAC is feasible in the majority of adult temporal bones and has implications for future hearing preservation drug delivery approaches to the IAC.
High-temperature argon broadening of CO 2 near 2190 cm −1 in a shock tube

Scanned-wavelength laser absorption measurements of CO2 diluted in Ar were performed behind reflected shock waves at high temperatures (1158–2017 K) and low pressures (5.1–108.4 kPa). High-resolution (0.001 cm−1) scans were conducted in 0.4-cm−1 increments from about 2188.8 to 2191.8 cm−1 at a scan rate of 2 kHz. The HITRAN 2004, HITRAN 2012, and CDSD-296 databases were all found to underestimate the absorption, typically by an order of magnitude or more. The HITEMP database, however, closely predicted the measured data. For the assumed form $$\gamma_{{{\text{CO}}_{ 2} - {\text{Ar}}}} (T) = \gamma_{{{\text{CO}}_{ 2} - {\text{Ar}}}} (T_{0} )(T_{0} /T)^{n}$$ with $$T_{0}$$ = 296 K, an optimization routine was implemented to determine the values of $$\gamma_{{{\text{CO}}_{ 2} - {\text{Ar}}}} (T_{0} )$$ and $$n$$ . From the optimization, values of 0.033 ± 0.004 cm−1 atm.−1 and 0.61 ± 0.04 were determined for $$\gamma_{{{\text{CO}}_{ 2} - {\text{Ar}}}} (T_{0} )$$ and $$n$$ , respectively, which are in good agreement with historical values. These values describe an average CO2–Ar broadening coefficient in the frequency range studied herein and are reliable within the experimental temperature range. In addition, a set of fixed-wavelength measurements at 2190.0175 cm−1 were carried out at 122, 446, and 1115 kPa between 1100 and 2100 K, and the HITEMP predictions incorporating the proposed Ar-broadening parameters showed excellent agreement with these data.
Birth to age 7 growth of children prenatally exposed to drugs: a prospective cohort study.

Abstract Prenatal exposure to cocaine, alcohol, and cigarettes has been linked to decreased birth weight and length. Unclear, however, is whether growth deficits persist into childhood. Women who were pregnant, African–American, not HIV-positive, and who delivered singleton infants were extensively screened throughout pregnancy for cocaine, alcohol, cigarette, and other illicit drug use. Of the approximately 1100 eligible subjects, 665 families were located at a 7-year postbirth follow-up and 540 participated. After appropriate control for potential confounders and prenatal exposures, prenatal exposure to cocaine, alcohol, and cigarettes each independently predicted birth weight and length. At age 7, prenatal cocaine exposure was significantly related to height deficits after accounting for other prenatal exposures and significant confounders. Children at age 7 exposed to cocaine in utero were up to 1 in. shorter and twice as likely to fall below the 10th percentile in height as the control children after accounting for other significant confounders including other prenatal exposures. Maternal age moderated the relation between prenatal exposures and child growth. Children born to women over 30 and exposed to cocaine were up to 2 in. shorter and four times more likely to have clinically significant height deficits at age 7. Children of older women and exposed to moderate-to-high levels of alcohol prenatally were up to 14 lb lighter and five times more likely to fall below the 10th percentile in weight. Similar growth restriction was not associated with prenatal exposures for children born to younger mothers. These outcomes add to the growing body of literature detailing long-term effects of prenatal drug exposure, suggesting differential effects for cocaine and alcohol, and indicating that maternal age may moderate these effects. Mechanisms for growth restriction and failure of catch-up under conditions of prenatal exposures are presented, suggesting further study of these developmental outcomes.
Effects of Temperature and Photorepair Radiation on a Marine Ciliate Exposed to UVB Radiation.

The influences of intensity and repeated exposure to ultraviolet-B radiation (UVB), photoreactivating repair radiation (PRR), and temperature on the scuticociliate Parauronema acutum were explored under laboratory conditions. Population growth was negatively affected after exposure to the equivalent of one sunny summer day of ambient UVB, especially in the absence of PRR. Repeated daily exposure to UVB severely compromised ciliate survival. UVB-exposed treatments without PRR recovered slower and reached lower final abundances than treatments receiving PRR. Reducing the daily UVB exposure approximately 25% improved ciliate recovery after exposure. In the single exposure treatments, temperature effects were not consistent, except that growth was slowest for control and treatments at the lowest temperature (15 °C). These data suggest that dark repair and/or photoprotection are present in P. acutum, but photoenzymatic repair was the more effective mechanism in reversing UVB damage. Repeated exposure treatments without PRR had zero or declining growth at all temperatures (15, 20 and 25 °C), as did those with PRR at 15 °C. Significant temperature/dose differences were identified in the repeated exposure treatments; ciliates subjected to the higher UVB intensity with PRR survived only at 25 °C, while ciliate populations under reduced UVB increased at 20 and 25 °C.