cssi/SciSciGPT-SciSciNet huggingface dataset:
Biventricular origin of the pulmonary trunk with subaortic stenosis above the ventricular septal defect.

Abstract Three cases are reported that presented a complex of congenital cardiac anomalies which consisted of biventricular origin of the pulmonary trunk with subaortic stenosis above a ventricular septal defect. In Case 1 the hemodynamic findings obtained at cardiac catheterization showed consistently higher ventricular and pulmonary arterial pressures when these were compared to systemic arterial pressure. Two patients were siblings with identical anatomic findings (Cases 2 and 3). Both of these patients had associated interruption of the aortic arch. The descending aorta, which gave rise to the subclavian arteries, communicated with the right ventricle through a patent ductus arteriosus. In one of the patients (Case 3), differential cyanosis was noted: the upper and lower extremities were cyanotic but the head was not cyanotic. Mild coarctation of the aorta was present in the third patient (Case 1).
Statistical inference and visualization in scale-space for spatially dependent images

SiZer (SIgnificant ZERo crossing of the derivatives) is a graphical scale-space visualization tool that allows for statistical inferences. In this paper we develop a spatial SiZer for finding significant features and conducting goodness-of-fit tests for spatially dependent images. The spatial SiZer utilizes a family of kernel estimates of the image and provides not only exploratory data analysis but also statistical inference with spatial correlation taken into account. It is also capable of comparing the observed image with a specific null model being tested by adjusting the statistical inference using an assumed covariance structure. Pixel locations having statistically significant differences between the image and a given null model are highlighted by arrows. The spatial SiZer is compared with the existing independent SiZer via the analysis of simulated data with and without signal on both planar and spherical domains. We apply the spatial SiZer method to the decadal temperature change over some regions of the Earth.
Detection of synchrony in the discharge of a population of neurons. II. Implementation and sensitivity of a synchronization index.

Abstract This report describes the use of a synchronization index ( I S ; Hamm et al., 1985a) and its sensitivity to various forms and degrees of synchrony between spike trains. The dependence of the I S on signal-to-noise ratio, the number of synchronized spike trains and their degree of synchrony is shown in analog and digital simulations. These simulations and a comparison with peristimulus time histograms under conditions of induced synchrony reveal that the I S is a sensitive measure of synchronization in a population of spike trains.
How low can I go? The impact of hypoglycemia on the immature brain.

Cerebral metabolism and function depends on adequate blood glucose, which provides for >90% of cerebral energy.1 Although the newborn brain is less vulnerable than the adult brain to the immediate functional and electrophysiological impact of hypoglycemia, epidemiologic and experimental evidence has confirmed cerebral injury related to isolated hypoglycemia in the newborn brain.2 In the July 2008 of Pediatrics , Burns et al3 described the neuroimaging findings and neurodevelopmental outcomes of 35 term infants with symptomatic hypoglycemia (86% of infants with a blood glucose of <35 mg/dL). The impact of isolated hypoglycemia on the developing brain has been well documented in animal experiments, including those on primates.2,4 These experiments have defined 3 important principles in relation to hypoglycemia-mediated cerebral injury in the newborn. First, prolonged and severe, rather than transient or minor, hypoglycemia was required … Address correspondence to Terrie Inder, MBChB, MD, FRACP, Washington University School of Medicine, Department of Neurology, 660 S Euclid Ave, St Louis, MO 63110. E-mail: inder_t{at}wustl.edu
Ethanol production from xylose with the yeast Pichia stipitis and simultaneous product recovery by gas stripping using a gas-lift loop fermentor with attached side-arm (GLSA).

The bioconversion of xylose into ethanol with the yeast Pichia stipitis CBS 5773 is inhibited when 20 g/L of ethanol are present in the fermentation broth. In order to avoid this limitation, the fermentation was carried out with simultaneous recovery of product by CO(2) stripping. The fermentation was also improved by attaching a side-arm to the main body of a classical gas-lift loop fermentor. This side-arm increases the liquid circulation, mass transfer, and gas distribution, reducing the amount of oxygen in the inlet gas necessary to perform the fermentation of xylose under microaerobic conditions (K(L)a approximately 16 h(-1)). The continuous stripping of ethanol from the fermentation broth in this new bioreactor system allowed the consumption of higher xylose concentrations than using Erlenmeyer shaker flasks, improved significantly the process productivity and provided a clean ethanol solution by using an ice-cooled condenser system. Finally, a fed-batch fermentation was carried out with a K(L)a = 15.8 h(-1). Starting with 248.2 g of xylose, 237.6 g of xylose was consumed to produce 88.1 g of ethanol which represents 72.6% of the theoretical yield (47.2 g/L of ethanol was recovered in the condenser, while 9.6 g/L remained in the fermentation broth).
Magnesium isotopic equilibrium in chlorophylls.

Photosynthesis generates ∼100 gigatons of carbon per year and drives many terrestrial geochemical cycles. Magnesium is the metal center in chlorophyll and is thus central to photosynthesis. Here we report measurements of the Mg isotopic composition of chlorophylls in English Ivy (Hedera helix L.) showing that chlorophyll-a is isotopically heavier than chlorophyll-b (Δ26MgChla-Chlb = 0.434 ‰ (±0.148) and Δ25MgChla-Chlb = 0.241 ‰ (±0.108)). The measurements are consistent with electronic structure calculations of the isotopic fractionation, implying that chlorophyll-a and -b are in isotopic equilibrium. Mg isotopic equilibrium suggests that the metal is labile in these molecules during the chlorophyll cycle after the various forms of chlorophyll are biosynthesized.
Histological study of pulps of human primary teeth

Abstract Twenty-seven primary human canines and incisors showing no clinical signs of caries, root resorption or restorative treatment were extracted for orthodontic purposes from patients ranging in age from 7 to 13 1 2 yr , and processed for histologic examination. Odontoblasts were pseudostratified in depths of 1–7 cells in a pulpward direction, with the thickest layers in the coronal pulp. The zone of Weil and the cell-rich zone were present in the coronal third of normal pulp, but absent in teeth with occlusal attrition. Vascular trunks were oriented coronally and exhibited increased branching as they approached the subodontoblastic layer. Collagenous fibers appeared coarse, densely packed, and coronally oriented in the apical third of the pulp, whereas the middle and coronal fibres were fine, loosely packed and randomly oriented. A cap-like dense zone of collagenous and reticular fibres was noted in pulp horns and the periphery of the coronal pulp. Von Korff's fibres were well developed in the coronal pulp but only poorly developed in apical and middle regions of the pulp. Focal mineralizations, closed apices, and a coronal-to-apical change in the staining characteristics of the predentine-odontoblastic border were also noted. There was no structural difference between primary human pulp and young permanent human pulp, other than the presence of a cap-like zone of reticular and collagenous fibres in primary coronal pulp.
Thermochemistry of the gas-phase equilibrium CH3COCH3 + Br2 = CH3COCH2Br + HBr. The enthalpy of formation of bromoacetone

The equilibrium constant for the gas-phase reaction: CH 3 COCH 3 + Br 2 = CH 3 COCH 2 Br + HBr , has been measured spectrophotometrically over the temperature range 516 to 618 K. From a calculated value of S°(CH3COCH2Br,g,298 K) = (84.2 ± 2) cal K−1mol−1 and the experimental equilibrium constants, the ‘third-law method’ yields ΔH°f(CH3COCH2Br,g,298 K) = −(43 ± 2.0) kcal mol−1 (using an estimated 〈ΔC°p〉 = (1.3 ± 1) cal K−1 mol−1) § Bromoacetone is less stable than predicted by both bond additivity and the atom substitution rule. This relative instability is presented as further evidence for intramolecular dipolar effects in α-halogenated ketones. Values of contributions to the group C-(CO)(H2)(Br) are ΔH°f(298 K) = − 1.2 kcal mol−1 and S°(298 K) = 41.2 cal K−1 mol−1.
A preliminary assessment of the new home seller capital gains law

Abstract In August 1997, the capital gains law was changed to enable most sellers to move down in price without incurring a tax liability. The previous law was critiqued as detrimental to cities by promoting out‐migration to higher‐priced homes; it was asserted that the requirement that sellers buy a home equal to or greater than the value of the one they sold to defer tax liability obstructed movement down in price. This study asked whether movement down in price increased in four Ohio cities after the law was changed and whether movement out of the central cities decreased and movement in from the suburbs increased. Statistically significant change in movement down was found in only one city. Movement up in price and outward dominated all four areas. The study produced no direct evidence of the factors that influenced seller‐buyer move decisions. The process of life‐course change—younger households moving up to larger, more expensive homes and older households moving down to smaller, less expensive prop...
Peroxisome Metabolism and Cellular Aging

The essential role of peroxisomes in fatty acid oxidation, anaplerotic metabolism, and hydrogen peroxide turnover is well established. Recent findings suggest that these and other related biochemical processes governed by the organelle may also play a critical role in regulating cellular aging. The goal of this review is to summarize and integrate into a model the evidence that peroxisome metabolism actually helps define the replicative and chronological age of a eukaryotic cell. In this model, peroxisomal reactive oxygen species (ROS) are seen as altering organelle biogenesis and function, and eliciting changes in the dynamic communication networks that exist between peroxisomes and other cellular compartments. At low levels, peroxisomal ROS activate an anti-aging program in the cell; at concentrations beyond a specific threshold, a pro-aging course is triggered.
Determining appropriate models for joint control using surface electrical stimulation of soleus in spinal cord injury.

The mechanical impedance of the ankle joint during electrical stimulation of the soleus is studied by applying constant-velocity 10° angular perturbations to the ankle and measuring the resultant torque. Both neurologically intact subjects and spinal cord injured subjects are tested. Lumped, piecewise linear models are developed to predict the torque from the measured displacement and acceleration signals. The commonly used second-order mass-spring-dashpot model fails to predict the changes in torque that occur following imposed movements. A fiveelement, directionally-dependent piecewise linear model is much better at predicting the measured responses for velocities up to 50° s−1. Numerical least squared error indentification techniques are used to estimate the model parameters for three neurologically intact and three spinal cord injured subjects. The average error between the model’s response and the measured response across all subjects is 10·9%. There is some evidence that a velocity-dependent non-linear model could produce better results than the directionally-dependent piecewise linear model.
The Sequence and Consequences of Bank Restructuring in South Korea, 1998––2006: Too Fast to Adjust

This paper explores the sequence, pace, and emerging outcomes of bank restructuring in South Korea since the financial crisis in late 1997, paying special attention to the state intervention pattern in regard to resolving non-performing loans and privatizing temporarily nationalized banks by foreign selling.
Use of Natural Analog and Modeling Studies to Constrain the Effects of Magmatic Activity on Long-Term Geologic Repositories

Examples of the application of natural-analog studies to the estimation of the consequences of a volcanic eruption penetrating a radioactive waste repository are given, including the criteria for analog selection and new data from ongoing studies. Examples of early modeling results focusing on the spatial and temporal scale of subsurface processes are also provided. All of these examples are taken from studies of the potential Yucca Mountain repository, Nevada, but similar approaches could be applied in other areas. In addition, studies of subsurface processes initiated by magmatic events serve as useful analogs for repository thermal loading studies.
Reducing Dynamic Foot Pressures in High-Risk Diabetic Subjects With Foot Ulcerations: A comparison of treatments

OBJECTIVE To compare the effectiveness of total contact casts, commercially available therapeutic shoes, and removable walking casts to reduce mean peak plantar foot pressures at the site of neuropathic ulcerations in diabetic subjects. RESEARCH DESIGN AND METHODS We compared the reduction in peak plantar pressures at ulcer sites under the great toe ( n = 5), first metatarsal ( n = 10), and second through fifth metatarsals ( n = 10) using six treatments: total contact casts (TCCs), DH Pressure Relief Walkers (DH), Aircast Pneumatic Walkers, Three D Dura-Steppers (3D), CAM Walkers, and P.W. Minor Xtra Depth shoes. A rubber sole canvas oxford was used to establish baseline pressure values. The canvas oxford could be viewed as a worse-case scenario for this patient population. With the EMED Pedar in-shoe pressure measurement system, data for 40 steps were collected for each treatment. We used Tukey9s Studentized Range Test for simultaneous multiple comparisons to compare treatments. RESULTS DH Pressure Relief Walkers reduced plantar pressures significantly better than other commercially available treatments for ulcers under the first metatarsal, second through fifth metatarsals, and great toe ( P CONCLUSIONS DH Pressure Relief Walkers were as effective as total contact casts to reduce foot pressures at ulcer sites and may be an effective practical addition in the treatment of foot ulcers.
Safety of misoprostol as a cervical ripening agent in vaginal birth after cesarean section

Abstract In women who underwent vaginal birth after cesarean section (VBAC), we assessed the risk of uterine rupture in those who received misoprostol and oxytocin (M+O) compared with that in two other groups—VBAC patients who had spontaneous labor (SL) and those who received oxytocin alone (OA). From 1996 to 1999, we compared risks for fetal and maternal complications, including uterine rupture, in M+O patients versus SL patients and in M+O patients versus OA patients. Other complications included abnormal heart rate pattern in labor, meconium passage, intrapartum infection, uterine rupture, and failure of VBAC. Of 382 VBAC patients studied, we had 100 patients in the M+O group, 115 in SL, and 167 in OA. There were no cases of uterine rupture in any of the three groups. Comparing M+O and SL patients, M+O patients were significantly less likely to have meconium ( P = .002) and less likely to have an abnormal heart rate pattern ( P = .02) than SL patients. Between M+O and OA patients, no statistically significant differences were identified in all outcomes measured. There were no cases of uterine rupture in any of the three groups. Three cases of uterine dehiscence were identified, but none of them received misoprostol. Success for vaginal delivery was statistically the same in all three groups (79% in M+O, 77% for SL, and 84% for OA). In conclusion, the use of misoprostol was not associated with an increased risk of abnormal fetal heart rate, maternal infection, or uterine rupture. In our series, misoprostol in VBAC patients was a relatively safe method for cervical ripening and as successful as spontaneous labor or oxytocin in vaginal delivery.
Non-destructive quantum measurement scheme for quantum states in superposition

The measurement of discrete quantum systems is a vital ingredient for quantum information processors. These systems, being fragile in nature, are characterized by a perturbation or collapse of their states whenever they are measured due to measurement-induced decoherence. We propose a quantum measurement model that allows for the extraction of information from any superposed quantum system without inducing a total collapse. The methodology used involves the coupling of a quantum probe through suitable interactions that create a partial entanglement between probe and quantum system. This entanglement in turn transfers information about the quantum system to the probe. Therefore, by making measurements on the probe rather than the superposed quantum system itself, we avert a total collapse to the quantum system.
Analyzing decentralized resource regimes from a polycentric perspective

This article seeks to shed new light on the study of decentralized natural resource governance by applying institutional theories of polycentricity—the relationships among multiple authorities with overlapping jurisdictions. The emphasis on multi-level dynamics has not penetrated empirical studies of environmental policy reforms in non-industrial countries. On the contrary, many of today’s decentralization proponents seem to be infatuated with the local sphere, expecting that local actors are always able and willing to govern their natural resources effectively. Existing studies in this area often focus exclusively on characteristics and performance of local institutions. While we certainly do not deny the importance of local institutions, we argue that institutional arrangements operating at other governance scales—such as national government agencies, international organizations, NGOs at multiple scales, and private associations—also often have critical roles to play in natural resource governance regimes, including self-organized regimes.
Bioactive Benzophenones from Garcinia xanthochymus Fruits

A MeOH extract of Garcinia xanthochymus fruits was subjected to activity-guided fractionation, yielding two new benzophenones, guttiferone H (1) and gambogenone (2). Compound 1 contains a seven-membered ring attached to the bicyclo[3.3.1]nonane system at positions 7 and 8 and displayed cytotoxicity in the SW-480 colon cancer cell line (IC(50) = 12 microM). Compound 2 has a novel benzophenone bicyclo[3.3.2]decane system and displayed cytotoxicity in the SW-480 colon cancer cell line (IC(50) = 188 microM). Both 1 and 2 induced apoptosis in SW-480 colon cancer cells and displayed antioxidant activity in the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay (IC(50) = 64 and 38.7 microM, respectively). The structures of 1 and 2 were established by 1D and 2D NMR data analysis. Eleven known compounds, aristophenone A, alloathyriol, amentoflavone, 3,8' '-biapigenin, cycloxanthochymol, (+/-)-fukugetin, (+/-)-fukugiside, guttiferone E, isoxanthochymol, (+/-)-volkensiflavone, and xanthochymol, were also obtained. The 11 known compounds were also tested against SW-480 colon cancer cells and in the DPPH assay.
Neuroblastoma and life-threatening tracheal obstruction: A case report and literature review

Abstract Thoracic neuroblastoma is a rare cause of life-threatening tracheal compression in paediatric oncology. We describe the case of a 5-month old boy with a 2-week history of progressive stridor, a right supraclavicular mass, a paravertebral/mediastinal mass on imaging and elevated urinary catecholamines. In view of the patient's threatened airway, a multidisciplinary management plan was agreed upon prior to obtaining a biopsy to confirm the diagnosis of neuroblastoma. Preoperative microlaryngobronchoscopy (MLB) demonstrated critical tracheal compression necessitating intubation. Neuroblastoma was confirmed on histology. Urgent cytoreductive treatment was initiated with excellent response allowing extubation 14 days later.
The effect of heat treatment temperature on the interfacial shear strength of C/C composites

This paper investigates the effect of heat treatment temperature on the interfacial shear strength (IFSS) of carbon/carbon composites reinforced with polyacrylonitrile-based fibers. A series of single fiber push-out tests were performed on specimens heat treated at 1800, 2100, and 2400 °C, using a nanoindenter with a flat ended conical tip. The microstructure was characterized using polarized light and transmission electron microscopy and the debonded fiber/matrix interface was examined using scanning electron microscopy. Wavelet analysis of the load–displacement data was used as an additional tool to investigate the initiation and progression of debonding. Compared to 1800 °C, heat treatment at 2400 °C was associated with a decrease in IFSS, from 12 to 7 MPa. Transmission electron microscopy study showed that the microstructure of the fiber/matrix interphase remained amorphous even with heat treatment at 2400 °C. The decrease in the IFSS can be partly attributed to the reorganization of the graphene sheets in the matrix in the vicinity of fiber/matrix interphase. The thermal expansion mismatch between fiber and pyrocarbon matrix is another possible reason for the observed decrease in the IFSS.
Toward computational identification of multiscale "tipping points" in acute inflammation and multiple organ failure.

Sepsis accounts annually for nearly 10% of total U.S. deaths, costing nearly $17 billion/year. Sepsis is a manifestation of disordered systemic inflammation. Properly regulated inflammation allows for timely recognition and effective reaction to injury or infection, but inadequate or overly robust inflammation can lead to Multiple Organ Dysfunction Syndrome (MODS). There is an incongruity between the systemic nature of disordered inflammation (as the target of inflammation-modulating therapies), and the regional manifestation of organ-specific failure (as the subject of organ support), that presents a therapeutic dilemma: systemic interventions can interfere with an individual organ system’s appropriate response, yet organ-specific interventions may not help the overall system reorient itself. Based on a decade of systems and computational approaches to deciphering acute inflammation, along with translationally-motivated experimental studies in both small and large animals, we propose that MODS evolves due to the feed-forward cycle of inflammation → damage → inflammation. We hypothesize that inflammation proceeds at a given, “nested” level or scale until positive feedback exceeds a “tipping point.” Below this tipping point, inflammation is contained and manageable; when this threshold is crossed, inflammation becomes disordered, and dysfunction propagates to a higher biological scale (e.g., progressing from cellular, to tissue/organ, to multiple organs, to the organism). Finally, we suggest that a combination of computational biology approaches involving data-driven and mechanistic mathematical modeling, in close association with studies in clinically relevant paradigms of sepsis/MODS, are necessary in order to define scale-specific “tipping points” and to suggest novel therapies for sepsis.
Fkh1 and Fkh2 bind multiple chromosomal elements in the S. cerevisiae genome with distinct specificities and cell cycle dynamics

Forkhead box (FOX) transcription factors regulate a wide variety of cellular functions in higher eukaryotes, including cell cycle control and developmental regulation. In Saccharomyces cerevisiae, Forkhead proteins Fkh1 and Fkh2 perform analogous functions, regulating genes involved in cell cycle control, while also regulating mating-type silencing and switching involved in gamete development. Recently, we revealed a novel role for Fkh1 and Fkh2 in the regulation of replication origin initiation timing, which, like donor preference in mating-type switching, appears to involve long-range chromosomal interactions, suggesting roles for Fkh1 and Fkh2 in chromatin architecture and organization. To elucidate how Fkh1 and Fkh2 regulate their target DNA elements and potentially regulate the spatial organization of the genome, we undertook a genome-wide analysis of Fkh1 and Fkh2 chromatin binding by ChIP-chip using tiling DNA microarrays. Our results confirm and extend previous findings showing that Fkh1 and Fkh2 control the expression of cell cycle-regulated genes. In addition, the data reveal hundreds of novel loci that bind Fkh1 only and exhibit a distinct chromatin structure from loci that bind both Fkh1 and Fkh2. The findings also show that Fkh1 plays the predominant role in the regulation of a subset of replication origins that initiate replication early, and that Fkh1/2 binding to these loci is cell cycle-regulated. Finally, we demonstrate that Fkh1 and Fkh2 bind proximally to a variety of genetic elements, including centromeres and Pol III-transcribed snoRNAs and tRNAs, greatly expanding their potential repertoire of functional targets, consistent with their recently suggested role in mediating the spatial organization of the genome.
A structural and histochemical study of the reaction complex in Crassostrea gigas (Mollusca) to Echinocephalus crassostreai (Nematoda).

A reaction complex develops aroung the gonoduct of the Japanese oyster, Crassostrea gigas , when parasitized by the nematode Echinocephalus crassostreai . This complex is comprised of connective tissue fibers, hemolymph cells, tightly packed Leydig cells, and brown cells. Although myofibers are also present, they are normally found in this region of C. gigas . Histochemical studies, involving the periodic acid-Schiff reaction, toluidine blue, alcian blue at p H 0.5, 2.6, and 5.7, and the ferrous iron method for melanin, have revealed some aspects of the chemical nature of the reaction complex. The presence of E. crassostreai also causes hyperactivity in the mucous cells intermingled among the ciliated lining epithelium of the gonoduct. Because of the structural separation of the intragonoductal parasites from the periductal reaction complex, it is postulated that the reaction is stimulated by molecules secreted and/or excreted by the nematodes and which are able to permeate through the lining epithelium and basal lamina.
Reading epilepsy : an appraisal of 20 patients diagnosed at the Mayo Clinic, Rochester, Minnesota, between 1949 and 1989, and delineation of the epileptic syndrome

The clinical and EEG findings in 20 patients with reading epilepsy (RE) diagnosed at the Mayo Clinic, Rochester, Minnesota, between 1949 and 1989 are documented in this study. Sixteen patients were followed for more than 10 years. The age at onset of RE ranged from 10 to 46 years (median 17.5 years). Precipitating factors other than reading, involving linguistic or non-linguistic higher cognitive processes, occurred in nine patients. Spontaneous myoclonus affecting the upper extremities, especially in the morning, indicated co-occurrence of juvenile myoclonic epilepsy (JME) in four patients. A positive family history for seizures (including one person with RE) was obtained for four patients. Interictal EEG abnormalities were present in 12 patients (60%). Ictal EEG findings were generalized and symmetric in 75% of patients, with a strictly focal (temporoparietal) discharge occurring in only two patients. Of the 11 patients who were alive and for whom recent information regarding seizure status was available, only three were symptom-free without anticonvulsant medication. Our data indicate resemblance of the clinical manifestations of RE with JME and other cognitive function-related seizures and point toward an overlap with them. We propose a classification for higher cognitive function-related epilepsies in general and RE in particular to explain the electrographic heterogeneity and clinical overlap observed. A hypothetical model to explain the ictogenesis and to encompass the electroclinical heterogeneity in RE is suggested.
Linearized models of a class of nonlinear dynamic systems

Abstract This paper studies the effect of certain types of nonlinearities on linearized model representations obtained from broadband (Gaussian white noise) input and output experimental data. These linearized models are commonly based on apparent transfer function measurements obtained from the input-output cross spectrum and the input spectrum. Since this apparent transfer function measurement is an estimate of the first-order Wiener kernel of the system in the frequency domain, the Volterra-Wiener functional expansions of the considered class of nonlinear differential systems is studied. Explicit analytical expressions are derived that show the dependence of the apparent transfer function on the input power level and the system nonlinearities. An example is presented that demonstrates the character of this dependence.
High-resolution X-ray diffraction and optical absorption study of heavily nitrogen-doped 4H–SiC crystals

Abstract Lattice parameter and optical absorption spectra were measured on heavily nitrogen-doped bulk crystals and epilayers of 4H–SiC. The rate of c -lattice parameter change versus doping concentration in high quality material was less than −3.6×10 −25 A cm 3 . In crystals containing high density of double stacking faults, the (0 0 0 8) X-ray reflection shifted toward the (2 2 2) reflection in 3C–SiC. Optical absorption measurements in such crystals detected peak at 3.1 eV similar to that reported in 3C–SiC with concomitant decrease of free carrier peak characteristic of 4H–SiC polytype.
XRF and XAFS analysis of electrophoretically isolated nondenatured proteins

Microbial metal reduction is relevant for developing bioremediation strategies for contaminated sites containing toxic metal compounds, but the molecular mechanisms involved and the regulation of those mechanisms are poorly understood. Metal reduction capability is microbe specific, yet the involvement of metalloproteins in the transport of electrons from electron donor molecules to electron acceptor molecules (i.e., to the metals to be reduced) is common to all metal-reducing organisms. A thorough understanding of the mechanisms involved in metal reduction by microbes, with a focus on their metalloproteins, will provide valuable information about the metal reduction capability of the organisms and could provide general insight into the mechanisms of metalloprotein expression and regulation in other microbial systems as well. We are developing methods for the efficient separation, detection, and quantification of metalloproteins. Electrophoretic methods for protein separation have been combined with x-ray fluorescence mapping and XAFS to determine the abundance and local chemical environment of iron within a cytochrome.
Experimental Study of Water Liquid-Vapor Two-Phase Pressure Drop Across an Array of Staggered Micropin-Fins

This study concerns pressure drop of adiabatic water liquid-vapor two-phase flow across an array of 1950 staggered square micropin-fins having a 200 X 200 μm cross section by 670 μm height. The ratios of longitudinal pitch and transverse pitch to pin-fin equivalent diameter are equal to 2. An inline immersion heater upstream of the micropin-fin test module was employed to produce liquid-vapor two-phase mixture, which flowed across the micropin-fin array. The test module was well insulated to maintain adiabatic condition. Four maximum mass velocities of 184 kg/m 2 s, 235 kg/m 2 s, 337 kg/m 2 s, and 391 kg/m 2 s, and a range of vapor qualities for each maximum mass velocity were tested. Measured pressure drop increases drastically with increasing vapor quality. Nine existing two-phase pressure drop models and correlations were assessed. The Lockhart― Martinelli correlation for laminar liquid-laminar vapor combination in conjunction with a single-phase friction factor correlation proposed for the present micropin-fin array provided the best agreement with the data.
One counter languages and the IRS condition

Any one counter language that is not nonterminal bounded must contain an infinite regular set; every generator of the family of one counter languages must contain an infinite regular set. Any language that is in the substitution closure of the linear and one counter languages but is not derivation bounded must contain an infinite regular set.
Purchasing power parity based on effective exchange rate and cointegration: 25 LDCs' experience with its absolute formulation

Abstract With the development of cointegration technique, the Purchasing Power Parity (PPP) theory has received renewed attention. Most studies have tested the theory by using data from developed countries (DCs) and some high-inflation, less-developed countries (LDCs). They have mostly rejected its empirical validity. In this paper we use the concept of effective exchange rate and quarterly data over 1973–1988 to examine the experience of 25 LDCs. For most countries we found little empirical support for the PPP.
Incorporation of [3H]palmitate into disaturated phosphatidylcholines in alveolar type II cells isolated by centrifugal elutriation.

Abstract In order to study synthesis of pulmonary surfactant materials, we measured incorporation of [3H]palmitate into disaturated phosphatidylcholines (PC) in alveolar type II cells isolated by centrifugal elutriation. The time course for this process is not linear and, at high external palmitate levels (1 mM), incorporation is maximal in 4–5 h. Incorporation is dependent on extracellular palmitate with a Vmax (at 1 mM) of 1.66 nmol palmitate incorporated into disaturated PC/4.2·105 cells per 2 h and a K 1 2 of 0.1 mM palmitate. Addition of an optimal amount of extracellular choline (0.05 mM) increases Vmax and decreases K 1 2 for palmitate. Incorporation of palmitate is dependent upon cell number, inhibited by extracellular Ca2+ and stimulated by external Mg2+ Cholinergic and β-adrenergic agonists do not increase incorporation. Pulmonary lavage fluid inhibits incorporation of palmitate into disaturated PC, suggesting there is negative feedback involved. Disaturated PC which has been recently synthesized (i.e., over a 2 h period) is broken down intracellularly by type II cells when they are suspended in palmitate-free medium. These results indicate that (1) several factors, such as substrate levels, cell number, Ca2+, Mg2+ and amount of surfactant present, are involved in the regulation of palmitate incorporation into disaturated PC; (2) disaturated PC which has been recently synthesized may be broken down by type II cells; and (3) surfactant synthesis in freshly isolated cells differs slightly from that reported by other investigators in type II cells maintained in primary cell culture.
The x-ray characteristic temperature of potassium bromide as a function of temperature

Abstract The X-ray characteristic temperature ΘM of KBr has been measured in the temperature range of 100–650°K. Using the frequency spectrum of KBr, which has recently been determined both from theoretical calculations and from neutral measurements of the dispersion relations, values of θM have been calculated over the same temperature range. At low temperatures the computed results are in excellent agreement with the experimental results. At high temperatures the experimental values decrease nearly linearly with temperature in accordance with that predicted by the explicit dependence of ΘM upon the volume. Values of the total root mean square displacement of the ions have been calculated as a function of temperature assuming both ions have the same temperature factor, which is a fair approximation according to recent theoretical calculations. Experimental values of the displacements are found to be in good agreement with theory at low temperatures but show a stronger temperature dependence at high temperatures.
Hydrophobic residues in helix 8 of cannabinoid receptor 1 are critical for structural and functional properties

In addition to the heptahelical transmembrane domain shared by all G protein-coupled receptors (GPCRs), many class A GPCRs adopt a helical domain, termed helix 8, in the membrane-proximal region of the C terminus. We investigated the role of residues in the hydrophobic and hydrophilic faces of amphiphilic helix 8 of human cannabinoid receptor 1 (CB1). To differentiate between a role for specific residues and global features, we made two key mutants: one involving replacement of the highly hydrophobic groups, Leu404, Phe408, and Phe412, all with alanine and the second involving substitution of the basic residues, Lys402, Arg405, and Arg409, all with the neutral glutamine. The former showed a very low B(max) based on binding isotherms, a minimal E(max) based on GTPgammaS binding analysis, and defective localization relative to the wild-type CB1 receptor as revealed by confocal microscopy. However, the latter mutant and the wild-type receptors were indistinguishable. Circular dichroism spectroscopy of purified peptides with corresponding sequences indicated that the highly hydrophobic residues are critical for maintaining a strong helical structure in detergent, whereas the positively charged residues are not. Further investigation of mutant receptors revealed that CB1 localization requires a threshold level of hydrophobicity but not specific amino acids. Moreover, mutant receptors carrying two- to six-residue insertions amino-terminal to helix 8 revealed a graded decrease in B(max) values. Our results identify the key helix 8 components (including hydrophobicity of specific residues, structure, and location relative to TM7) determinant for receptor localization leading to robust ligand binding and G protein activation.
Spectrum sharing radios

A major shift in radio design is now just beginning which attempts to share spectrum in a fundamentally new way. These radios are addressing the fact that spectrum is actually poorly utilized in many bands, in spite of the increasing demand for wireless connectivity. The new approaches to spectrum sharing make use of the advances in technology to implement new wireless systems that can share previously allocated spectra in such a way that the primary users of these spectra are not affected. Additionally, the allowed use of this band is on an unlicensed basis. Two methods that are being investigated to accomplish this task are the use of ultra wideband transmission and cognitive techniques. Ultra wideband transmission relies on the fact that if the bandwidth is increased, that reliable data transmission can occur even at power levels so low that primary radios in the same spectral bands are not affected. On the other hand the cognitive approach does not necessarily limit the transmission power, but rather attempts to share the spectra through a dynamic avoidance strategy. The opportunities and challenges of this new era in radio design are described along with the open questions in their implementation
Geometrical optics exact solutions for two classes of dielectric wedge structures

Two classes of dielectric wedges with a common edge are considered. For a certain direction of incidence and polarization of the primary plane wave, conditions are given under which total transmission occurs at all interfaces, i.e., the edge does not scatter and geometrical optics is the exact solution to the boundary value problem.
Environmental contaminants in bald eagle eggs from the Aleutian archipelago

We collected 136 fresh and unhatched eggs from bald eagle (Haliaeetus leucocephalus) nests and assessed productivity on eight islands in the Aleutian archipelago, 2000 to 2002. Egg contents were analyzed for a broad spectrum of organochlorine (OC) contaminants, mercury (Hg), and stable isotopes of carbon (delta13C) and nitrogen (delta15N). Concentrations of polychlorinated biphenyls (SigmaPCBs), p,p'-dichlorodiphenyldichloroethylene (DDE), and Hg in bald eagle eggs were elevated throughout the archipelago, but the patterns of distribution differed among the various contaminants. Total PCBs were highest in areas of past military activities on Adak and Amchitka Islands, indicating local point sources of these compounds. Concentrations of DDE and Hg were higher on Amchitka Island, which was subjected to much military activity during World War II and the middle of the 20th century. Concentrations of SigmaPCBs also were elevated on islands with little history of military activity (e.g., Amlia, Tanaga, Buldir), suggesting non-point sources of PCBs in addition to point sources. Concentrations of DDE and Hg were highest in eagle eggs from the most western Aleutian Islands (e.g., Buldir, Kiska) and decreased eastward along the Aleutian chain. This east-to-west increase suggested a Eurasian source of contamination, possibly through global transport and atmospheric distillation and/or from migratory seabirds. Eggshell thickness and productivity of bald eagles were normal and indicative of healthy populations because concentrations of most contaminants were below threshold levels for effects on reproduction. Contrary to our predictions, contaminant concentrations were not correlated with stable isotopes of carbon (delta13C) or nitrogen (delta15N) in eggs. These latter findings indicate that contaminant concentrations were influenced more by point sources and geographic location than trophic status of eagles among the different islands.
Fractionation of two mosquitocidal activities from alkali-solubilized extracts of Bacillus thuringiensis subspecies israelensis spores and parasporal inclusions.

Abstract Incubation of Bacillus thuringiensis subsp. israelensis spore-crystal mixtures with alkaline solutions gave a soluble fraction that was toxic to both Aedes aegypti and Drosophila melanogaster larvae, as well as being cytolytic to both primary tissue culture cells derived from D. melanogaster embryos and sheep red blood cells. Sephadex G 75 gel filtration chromatography of the alkali-solubilized material resolved two fractions. The first fraction to elute from the columns was mosquitocidal but not cytolytic. The second fraction was cytolytic as well as mosquitocidal. In addition, only the cytolytic fraction had larvicidal activity against D. melanogaster . A protein, of approximately 27,000 Da having cytolytic activity, mosquitocidal activity, and toxic to D. melanogaster larvae, was purified from the second fraction. The rate of in vitro alkali solubilization of the mosquitocidal-noncytolytic activity was different from that of the mosquitocidal-cytolytic activity.
Strong influence of microhabitat on survival for an intertidal snail, Nucella lima

Within a population, survival can vary widely among individuals based upon numerous aspects of the phenotype, including (but not limited to) age, size, and habitat use. We examined the role of microhabitat use, individual color, and length, in explaining within-population variation in survival for an intertidal snail, Nucella lima. We used a multi-state capture–mark–recapture approach to determine survival and movement rates and found that favored models constrained survival to be a function of microhabitat. Survival estimates from the best-fit model were different between habitat types, despite the fact that habitats were immediately adjacent. Fidelity and disproportionate movement into the habitat with the highest survival suggested possible adaptive habitat choice. This study highlights the importance of small-scale variation in influencing population vital rates, as well as the need for quantifying within-population heterogeneity in survival.
The politics of privatization in Tanzania

Abstract Privatizing education appeals to both African educators and international educational assistance agencies as a response to increasing demand and declining resources. Locally supported schools transfer a major portion of educational funding from the public treasury to students and their families, and can facilitate popular participation in educational decision making. Yet, privatization is not simply a strategy for shifting costs. Precisely because it increases local autonomy, privatization undermines efforts to reduce regional, and thus racial and ethnic, inequalities. Privatization also enhances the influence of those able to secure local and external funds. Tanzania's changing policies toward private schools illustrate the tension between equality and expanded access and illuminate the politics of its resolution.
Effects of MCI-154 on Ca2+ activation of skinned human myocardium.

Abstract We investigated the effects of MCI-154, a new inotropic agent, on tension development in saponin-skinned human trabeculae carneae. The skinned fibers were activated by buffer solutions containing varying concentrations of Ca 2+ (10 −8 -10 −4 M). In the sigmoidal tension vs. pCa (−log[Ca 2+ ]M) relationship, the Ca 2+ concentration required for half-maximal activation was shifted leftward in the presence of MCI-154. Furthermore, maximal Ca 2+ -activated tension development was increased in a concentration-dependent manner by MCI-154. Our results suggest that the inotropic effect of MCI-154 may be due, in part, to an increased sensitivity of the myofilaments to Ca 2+ and enhancement of maximal Ca 2+ -activated tension development.
Bionanofabrication of Ordered Nanoparticle Arrays: Effect of Particle Properties and Adsorption Conditions

Arrays of Au nanoparticles were created using the inherent repeating patterns of bacterial S-layer proteins. Bacterial self-assembling S-layer protein lattices display a highly repetitive surface structure that makes them particularly suitable as biotemplates to fabricate metallic/semiconducting nanostructures and arrays. One interesting S-layer for nanoparticle templating is the hexagonally packed intermediate (HPI) layer of Deinococcus radiodurans . This S-layer, displaying hexagonal (p6) symmetry, is comprised of a hexameric protein core unit with a central pore, surrounded by six relatively large openings (“vertex points”). In this work, the influences of particle properties and adsorption conditions on the formation of ordered arrays of 5-nm Au nanoparticles using HPI S-layers were investigated. Using transmission electron microscopy (TEM), it was found that the templating of citrate-capped Au nanoparticles on HPI layers under low ionic strength conditions resulted in hexagonal-packed ordered arrays with 18-nm interparticle spacings that corresponded with the pore-to-pore distance of the S-layer. Interestingly, nanoparticle binding occurs at the vertex points on the HPI layer and, due to repulsion forces, adsorption tends to be favored at every second vertex point. Upon increasing the ionic strength, ordered packing is still observed. However, because interparticle repulsions are less prominent, adsorption of nanoparticles occurs in virtually every available vertex point, resulting in the formation of a honeycomb-like pattern of nanoparticles extending throughout the HPI monolayer sheet. Combined with the results of additional investigations using either uncharged hydroxy-terminated particles or positively charged ferritin molecules, the experimental data suggest that the creation of ordered arrays through biotemplating of Au nanoparticles onto HPI S-layers depends on the electrostatic interactions between individual nanoparticles as well as the interaction with the HPI layer.