cssi/SciSciGPT-SciSciNet huggingface dataset:
Structure-Function Studies with the Mitochondrial Carnitine Palmitoyltransferases I and II

Mitochondrial carnitine palmitoyltransferases I and II (CPTI and CPTII), together with the carnitine carrier, transport long-chain fatty acyl-CoAs from the cytosol to the mitochondrial matrix for β-oxidation. As an enzyme that catalyzes the rate-limiting step in fatty acid oxidation, CPTI is inhibited by malonyl-CoA, the first intermediate in fatty acid synthesis. Our development of a high level of expression for CPTI and CPTII in P. pastoris, a yeast with no endogenous CPT activity has enabled us to map the malonyl-CoA and substrate binding sites by mutational analysis. Using deletion and substitution mutants of L-CPTI expressed in P. pastoris, we have shown that Glu3 and His5 are necessary for malonyl-CoA inhibition and high-affinity binding of L-CPTI but not for catalysis. Similar studies of M-CPTI clearly establish that the N-terminal residues Glu3, Val19, Leu23, and Ser24 in M-CPTI are important for malonyl-CoA inhibition and binding, but not for catalysis. Furthermore, using chimeras between rat and pig L-CPTI, and deletion mutation analysis, we demonstrated that the differences in malonyl-CoA sensitivity observed between the pig and rat L-CPTI were due to differences in the interaction of the first 18 N-terminal amino acid residues with the C-terminal region of the respective enzymes. Consistent with this, the conserved C-terminal residues R601, E603, R606, and K560 were found to be important for L-CPTI activity, malonyl-CoA inhibition and binding, because mutation of these residues decreased malonyl-CoA sensitivity and enzyme activity. We also identified two conserved C-terminal residues in L-CPTI, D567, and E590, that when mutated to alanine cause a substantial increase in malonyl-CoA sensitivity, suggesting a structural basis for the differences in malonyl-CoA sensitivity between L-CPTI and M-CPTI. Our cysteine-scanning mutagenesis of M-CPTI revealed that a single Cys residue, Cys305, was essential for catalysis. In addition, deletion and substitution analysis of the extreme C-terminal region of M-CPTI, suggest that L764 may be important for proper folding and optimal activity. In summary, our structure-function studies with the mitochondrial carnitine palmitoyltransferases I and II have identified critical residues for inhibitor and substrate binding and catalysis.
A field studies and modeling approach to develop organochlorine pesticide and PCB total maximum daily load calculations: case study for Echo Park Lake, Los Angeles, CA.

Echo Park Lake is a small lake in Los Angeles, CA listed on the USA Clean Water Act Section 303(d) list of impaired water bodies for elevated levels of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in fish tissue. A lake water and sediment sampling program was completed to support the development of total maximum daily loads (TMDL) to address the lake impairment. The field data indicated quantifiable levels of OCPs and PCBs in the sediments, but lake water data were all below detection levels. The field sediment data obtained may explain the contaminant levels in fish tissue using appropriate sediment–water partitioning coefficients and bioaccumulation factors. A partition-equilibrium fugacity model of the whole lake system was used to interpret the field data and indicated that half of the total mass of the pollutants in the system are in the sediments and the other half is in soil; therefore, soil erosion could be a significant pollutant transport mode into the lake. Modeling also indicated that developing and quantifying the TMDL depends significantly on the analytical detection level for the pollutants in field samples and on the choice of octanol-water partitioning coefficient and bioaccumulation factors for the model.
Type-level Computation Using Narrowing in Ωmega

@Wmega is an experimental system that combines features of both a programming language and a logical reasoning system. @Wmega is a language with an infinite hierarchy of computational levels. Terms at one level are classified (or typed) by terms at the next higher level. In this paper we report on using two different computational mechanisms. At the value level, computation is performed by reduction, and is largely unconstrained. At all higher levels, computation is performed by narrowing.
Multiple cerebral hemorrhages in HTLV‐I‐associated myelopathy

We describe a 66-year-old woman with long-standing HTLV-I-associated myelopathy who developed multiple parenchymal hemorrhages and whose angiogram suggested cerebral vasculitis. After cyclophosphamide and glucocorticoid therapy, both her acute deficits and chronic paraparesis improved. HTLV-I may be an etiologic agent in isolated angiitis of CNS.
Defect structures in amorphous Germanium films

The structures of 100 A thick films of amorphous Ge ion implanted with 74Ge with energies of 10, 20, and 40 keV, and dosages of 3 × 1014 to 1015 ions/cm2, are determined by high energy electron diffraction and microscopy. Films bombarded with ion energies greater than 20 keV show a microstructure consisting of widely spaced pores having a maximum diameter of 100 A. The presence of these pores is found to be independent of the substrate (NaCl and collodion coated glass), but dependent on film thickness. These large pores are not observed for the lower implantation energies. For low energy implantation and high dosages the reduced intensity function showed a considerable decrease in the intensity of the second interference peak as well as different low angle scattering. To interpret these results the concept of monovacaneies and divacancies is defined for the amorphous structures, and it is shown that the structure of these ion implanted films can be adequately described as a random network containing a uniform distribution of these point imperfections. La structure de couches tres minces (100 A) de Ge amorphe, preparees par implantation d'ions de 74Ge d'energies de 10, 20 et 40 keV et de doses de 3 × 1014 a 1015 ions/cm2, a ete determinee par diffraction d'electrons de haute energie et par microscope electronique. Les couches minces bombardees avec des ions d'energie superieure a 20 keV possedent une microstructure caracterisee par des pores tres espacees dont le diametre maximum est 100 A. Le presence de ces pores est independante du substrat (NaCl ou verre recouvert de ‘collodion’) mais depend de l'epaisseur de la couche mince. Ces grandes pores n'ont pas ete observees pour des energies d'implantation inferieures a 20 keV. Pour les implantations de basse energie et dose elevee, la fonction intensite reduite decroit considerablement dans l'intensite du second pique ainsi que differents petits angles de diffraction. Dans le but d'interpreter ces resultats nons definissons le concept de ‘monovacance’ et ‘bivacance’ en relation avec l'etat amorphe et montrons que la structure des couches minces preparees par implantation d'ions peut ětre decrite de maniere adequate par un reseau aleatoire contenant des imperfections ponctuelles distribuees uniformement.
Investigation of Drug Release From Biodegradable PLG Microspheres: Experiment and Theory

Piroxicam containing PLG microspheres having different size distributions were fabricated, and in vitro release kinetics were determined for each preparation. Based on the experimental results, a suitable mathematical theory has been developed that incorporates the effect of microsphere size distribution and polymer degradation on drug release. We show from in vitro release experiments that microsphere size has a significant effect on drug release rate. The initial release rate decreased with an increase in microsphere size. In addition, the release profile changed from first order to concave-upward (sigmoidal) as the system size was increased. The mathematical model gave a good fit to the experimental release data.Copyright © 2007 by ASME
Reactions of simple carbonaceous fuels at a platinized platinum electrode partially covered by pre-adsorbed copper atoms

Summary A certain fraction of a pre-adsorbed layer of copper atoms disappears from the surface of platinized platinum at open circuit during the stirring with carbon monoxide in 0.5 M H 2 SO 4 as a result of a mixed electrode process. Possible reactions are given for this process. A mixed layer, consisting of Cu ad and CO ad , completely covers the surface at the end of the experiment. The influence of Cu ad on the steadystate oxidation of CO, HCOOH, and CH 3 OH is a specific one. While the oxidation rates of CO and HCOOH are increased, the oxidation of CH 3 OH is slightly inhibited. A mixed layer of copper atoms and strongly adsorbed carbonaceous species is formed during the steady-state oxidation of HCOOH and CH 3 OH.
Ectopic Varices in the Gastrointestinal Tract: Short- and Long-Term Outcomes of Percutaneous Therapy

To evaluate the results of percutaneous management of ectopic varices, a retrospective review was carried out of 14 patients (9 men, 5 women; mean age 58 years) who between 1992 and 2001 underwent interventional radiological techniques for management of bleeding ectopic varices. A history of prior abdominal surgery was present in 12 of 14 patients. The interval between the surgery and percutaneous intervention ranged from 2 to 38 years. Transhepatic portal venography confirmed ectopic varices to be the source of portal hypertension-related gastrointestinal bleeding. Embolization of the ectopic varices was performed by a transhepatic approach with coil embolization of the veins draining into the ectopic varices. Transjugular intrahepatic portosystemic shunt (TIPS) was performed in the standard fashion. Eighteen procedures (12 primary coil embolizations, 1 primary TIPS, 2 re-embolizations, 3 secondary TIPS) were performed in 13 patients. One patient was not a candidate for percutaneous treatment. All interventions but one (re-embolization) were technically successful. In 2 of 18 interventions, re-bleeding occurred within 72 hr (both embolization patients). Recurrent bleeding (23 days to 27 months after initial intervention) was identified in 9 procedures (8 coil embolizations, 1 TIPS due to biliary fistula). One patient had TIPS revision because of ultrasound surveillance findings. New encephalopathy developed in 2 of 4 TIPS patients. Percutaneous coil embolization is a simple and safe treatment for bleeding ectopic varices; however, recurrent bleeding is frequent and reintervention often required. TIPS can offer good control of bleeding at the expense of a more complex procedure and associated risk of encephalopathy.
Kronecker sequences for spread-spectrum communication

The paper considers the correlation properties of sets of sequences in which each sequence is constructed by taking the Kronecker product (or tensor product) of two short sequences. It is shown that if the short sequences are carefully chosen then the correlation properties of such sets are nearly as good as those of sequences of comparable length that have been obtained by other means. Furthermore, it is much easier to optimise the phases of these sequences because of the structure that they inherit from the Kronecker product operation. This structure also enhances the ease of synchronisation for such sequences. If the signal/noise ratio is large, the time required to synchronise to Kronecker sequences is significantly less than the time required to synchronise to other sequences of comparable lengths. Thus, the Kronecker sequences allow one to achieve rapid acquisition at the expense of a very small deterioration in some of the correlation properties.
Genetic and environmental influences on reading and listening comprehension

We report preliminary behaviour genetic analyses of reading and listening comprehension from The Colorado Learning Disabilities Research Center. Although the twin sample with these new measures is still of limited size, we find substantial, and significant, genetic influences on individual differences in both reading and listening comprehension. In addition, word recognition and listening comprehension each accounted for significant independent genetic influences on reading comprehension. Together, they accounted for all the genetic influence on reading comprehension, indicating a largely genetic basis for the ‘simple model’ of individual differences in reading comprehension proposed by Hoover and Gough (1990).
Proof of mycotoxicoses being a field problem and a simple method for their control.

Abstract A field trial in which moldy caked feed was removed from the feed delivery truck, storage bins, conveyors, and feeding troughs by scrubbing and disinfecting resulted in improved body weight, pigmentation, and carcass grade of broiler chickens. This improvement which occurred despite the presence of only small and infrequent quantities of aflatoxin and ochratoxin suggests that mycotoxicoses, as yet undefined, can have a deleterious economic effect and further suggests that the mycotoxicoses can be partially controlled by simple preventive measures.
Processing of compressed and encrypted imagery: complexity analyses with application to novel regimes of efficient computation

Computational efficiencies can accrue from the processing of compressed imagery, due to an inherently reduced data burden. Since certain encryption schemes yield compressed ciphertext, computations over the range space of compressive or encryptive transformations can, in principle, exhibit computational advantages over the processing of uncompressed data or plaintext. We have recently elucidated theory fundamental to the processing of compressed and encrypted imagery, and have proposed general techniques for computation over well- known compressive formats. In this introductory paper, we analyze the efficiency of generalized operations over compressed data, with emphasis upon functions common to image and signal processing. Complexity theory derived from principles of sparse matrix processing is employed in the prediction of a critical compression ratio (CCR). Compression exceeding the CCR is required to achieve computational speedup within a given transformational regime. Additionally, given the compression ratio of a transform, as well as an image operation, we can predict the speedup of the corresponding operation over the transform's range space. Furthermore, we propose a novel computational paradigm which is based upon a network of transformations, and given optimization algorithms which determine the time-optimal computational path through such a network.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
A precision measurement of the longitudinal polarization of betas following P32 decay

Abstract The method of Mott scattering has been used to determine the longitudinal polarization of 616 keV betas from the allowed Gamow-Teller decay of P32. After rotation of the spin from longitudinal to transverse by a spherical electrostatic analyser, the up-down asymmetry was measured over a wide range of gold target thickness. Source depolarization, plate scattering depolarization, multiple and plural scattering in gold and aluminium targets and instrumental asymmetry effects were carefully investigated experimentally. Corrections were made for various backgrounds, wall scattering, finite geometry and fringing fields. The final value of P = (−0.990±0.009)υ/c for υ/c = 0.891 depends upon a calculated value of the Most-scattering function S(θ), which has not been corrected for screening, inelastic scattering, Schwinger radiative loss, or finite nuclear size effects. These are estimated to be the order of 2 % or less. Neglecting these effects and small theoretical corrections to the polarization which result from such effects as Δl-forbiddenness and finite nuclear size, this experimental result can be interpreted in terms of the beta-decay coupling constants. If time reversal invariance and the two-component neutrino theory are assumed, the ratio C T C A = 0.011±0.010 is computed from the measured polarization. On the other hand, assuming time reversal invariance and CT = C′T = O, then the ratio C′ A C A is limited to the range +0.82 to +1.22 by the result reported here.
Regulation of antigen receptor gene assembly in lymphocytes.

Somatic alterations affecting the mammalian genome occur exclusively in B and T cells. Developing lymphocytes employ a series of DNA recombination events (V(D)J recombination) to assemble a diverse repertoire of immunoglobulin (Ig) and T cell receptor (TCR) variable regions from a large array of germline gene segments. V(D)J recombination is required not only for receptor diversification but also for lymphocyte development. At a molecular level, these recombination events are directed by conserved DNA sequences flanking all antigen receptor gene segments that function as recognition signals for a single recombinase activity. Despite these shared features, recombination events are controlled at the levels of stage-and tissue-specificity. Our primary research focus is to dissect the mechanisms that regulate assembly of antigen receptor loci by rendering certain gene segments accesible to a common V(D)J recombinase.This article discusses recent discoveries from the author's laboratory that address this long-standing issue. We have found that transcriptional promoters are critical cis-acting regulatory elements for targeting efficient recombination of chromosomal gene segments. We have also demonstrated that activation of NF-κB signaling in precursor B cells is required for global regulation of Ig light chain gene assembly. Together, these findings provide key insights into the genetic mechanisms that regulate antigen receptor diversity and the developmental pathways leading to the acquisition of lymphocyte effector function.
A parallel network simulation and virtual time-based network emulation testbed

To analyse large-scale systems with high fidelity, it is necessary for a network testbed to offer both realistic emulation (to represent software execution) and effective simulation (to model background computation and communication). We present a network testbed that integrates a lightweight emulation system (modified earlier to operate in virtual time) with a parallel discrete event network simulator. Our contributions lie in the design of a global synchronization algorithm to manage virtual time as it transitions from emulation to simulation, and back. In particular, we optimize our previous algorithm to reduce overhead of synchronizations across simulation and emulation. We also address the unavoidable uncertainties introduced by the emulation by obtaining analytical bounds for the error, and produce empirical data showing that the error is as small as the minimum system execution unit. In addition, we observe excellent system scalability with large-scale network experiments, and demonstrate the performance improvement of the optimized global synchronization algorithm.
The Interaction of Mycoplasmas and Influenza Viruses in Tracheal Organ Cultures

Organ cultures of porcine and bovine trachea were used as host systems in a study of interactions between influenza viruses and mycoplasmas. While Mycoplasma hyorhinis produced only minimal histopathological changes in the epithelium and swine-influenza virus produced moderate damage, there was some evidence that a double infection with both agents increased the destruction of the respiratory epithelium. This effect was not seen when influenza A WS was used, or when bovine instead of porcine cultures were used as the host system. Titers of virus in the organ culture fluids were unaltered by the presence of concurrent infection with M. hyorhinis, but growth of this mycoplasma was enhanced in cultures infected with swine-influenza virus as compared with control cultures. An examination of bovine tracheal cultures infected with swine-influenza virus and a bovine T-strain mycoplasma, either singly or in combination, showed no evidence of interaction between these two agents.
A cannula for use in ultrasonically guided biopsies of the brain. Technical note.

✓ The authors describe a cannula that has been modified to improve its visibility during ultrasonically guided biopsies of the brain. To enhance the echogenicity of the tip of the cannula, six parallel rings, 0.25 to 0.30 mm deep and 0.40 to 0.50 mm apart, were etched into the tip of the cannula. The cannula was also lengthened to approximately 19 cm to permit its unencumbered passage through any biopsy guidance device that may be employed. Detailing the precise location of the tip of the biopsy cannula is most important. The tip of this modified probe is much more echogenic and hence more easily seen ultrasonically than it would be otherwise, both in vivo and in vitro. This modified cannula is useful in any ultrasonically guided intracranial biopsy procedure.
GaN microdomes for broadband omnidirectional antireflection for concentrator photovoltaics

GaN microdomes are studied as a broadband omnidirectional anti-reflection structure for high efficiency multi-junction concentrated photovoltaics. Comprehensive studies of the effect of GaN microdome sizes and shapes on the light collection efficiency were studied. The three dimensional finite difference time domain (3-D FDTD) method was used to calculate the surface reflectance of GaN microdomes as compared to that of the flat surface. Studies indicate significant reduction of the surface reflectance is achievable by properly designing the microdome structures. Formation of the GaN microdomes with the flexibility to tune the size and shape has been demonstrated by using reactive ion etching (RIE) of both GaN and the self-assembled silica monolayer microspheres. Characterizations of the angle-dependence light surface reflectance for both micro-domes and flat surface show the similar trend as the simulation.
Regulation of pyrimidine biosynthesis by purine and pyrimidine nucleosides in slices of rat tissue.

Abstract Evidence of the primary sites for the regulation of de novo pyrimidine biosynthesis by purine and pyrimidine nucleosides has been obtained in tissue slices through measurements of the incorporation of radiolabeled precursors into an intermediate and end product of the pathway. Both purine and pyrimidine nucleosides inhibited the incorporation of [14C]-NaHCO3 into orotic acid and uridine nucleotides, and the inhibition was found to be reversible upon transferring the tissue slices to a medium lacking nucleoside. The ammonia-stimulated incorporation of [14C]NaHCO3 into orotic acid, which is unique to liver slices, was sensitive to inhibition by pyrimidine nucleosides at physiological levels of ammonia, but this regulatory mechanism was lost at toxic levels of ammonia. Adenosine, but not uridine, was found to have the additional effects of inhibiting the conversion of [14C]orotic acid to UMP and depleting the tissue slices of PRPP. Since PRPP is required as an activator of the first enzyme of the de novo pathway, CPSase II, and a substrate of the fifth enzyme, OPRTase, these results indicate that adenosine inhibits the incorporation of [14C]NaHCO3 into orotic acid and the incorporation of [14C]orotic acid into UMP by depriving CPSase II and OPRTase, respectively, of PRPP. Uridine or its metabolites, on the other hand, appear to control the de novo biosynthesis of pyrimidines through end product inhibition of an early enzyme, most likely CPSase II. We found no evidence of end product inhibition of the conversion of orotic acid to UMP in tissue slices.
Interaction Potentials and Vibrational Effects in the Acetylene Dimer

Ab initio calculations were carried out for critical point regions of the acetylene dimer potential surface with different basis sets, with and without the inclusion of counterpoise correction, and at two different electron correlation levels. The results were used to determine parameters for model interaction potentials with different forms for their electrostatic terms. Vibrational quantum Monte Carlo calculations for rigid monomers were performed using each of the model potentials, and refinements of the few parameters in the model potentials were obtained, such that the calculated rotational constant for the ground vibrational state matched the experimentally determined value. Comparison of features of the resulting surfaces showed that similar surfaces could be obtained from the different ab initio starting points, an indication of the suitability of the potentials' forms and of the nature of lingering errors in the ab initio treatments. This provides a very useful basis for more general model develo...
Subcellular Origin and Tissue-Wide Synchronization of Abnormal Ca Release in the Genesis of Ca-Dependent Atrial Arrhythmia

Introduction. Abnormal diastolic Ca release (DCR) from the sarcoplasmic reticulum has been implicated in both ventricular as well as atrial fibrillation (AF). Atrial cells lack the extensive T-tubule network that facilitates Ca signaling in ventricular myocytes. How the distinct structural organization of atrial cells affects the genesis of AF is currently unknown.Methods and Results. We used rapid 2D confocal imaging to map Ca changes in atrial single myocytes and tissue preparations derived from CASQ2 knock-out (CASQ2.KO) mice manifesting Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT). Isolated CASQ2.KO atrial cells showed frequent local and cell-wide DCR events when exposed to isoproterenol. DCR predominantly originated nearly simultaneously at several “eager” sites localized at cell periphery. The distribution of latencies to local DCR events in CASQ2.KO cells displayed a left-ward shift consistent with abbreviated RyR2 refractoriness associated with CPVT. This abbreviated RyR2 refractoriness translated into highly synchronous spontaneous Ca oscillations across the intact atrial tissue. Conditional overexpression of SERCA2a in CASQ.KO mice exacerbated proarrhythmic Ca oscillations by increasing the proportion of interior eager release sites and enhancing DCR synchronicity in both isolated atrial cells and atrial tissue preparations.Conclusions. Our results suggest that aberrant DCR involves a certain set of eager Ca release sites that 1) only in part coincide with sites involved in normal EC coupling at cell periphery and 2) act as "pacemakers" for spontaneous Ca oscillations present in atrial cells. Due to abbreviated release site refractoriness, DCR is synchronized between neighboring cells thereby leading to tissue-wide Ca oscillations that may form basis for AF. SERCA2a overexpression exacerbates arrhythmic Ca oscillations by further enhancing DCR synchronicity.
Neural net and genetic algorithms for spectral pattern recognition

Spectral pattern recognition (SPR) methods are among the most powerful tools currently available for noriinvasively examhiin the spectroscopic and other chemical data for environmental analysis and monitoring. Using spectral data, these systems have found a variety of applications in chemometric systems such as gas chromatography, fluorescence spectroscopy, etc. An advantage of SPR approaches is that they make no a priori assumption regarding the structure of spectra. However, a majority o these systems rely on humanjudgment for parameter selection and classification. We considered a SPR problem as a composite of five subproblems: pattern acquisition, feature extraction, feature selection, knowledge organization, and pattern classification. One ofthe basic issues in SPR approaches is to determine and measure the features useful for successful classification. Selection of features that contain the most discriminatory information is important because the cost of pattern classification is directly related to the number offeatures used for classification. Various features present in a pattern and a large variety of classification algorithms could be used. A spectral pattern classification system combining the above components and multivariate decisiontheoretic approaches for classification is developed. It is shown how such a system can be used for large data analysis, warehousing, and interpretation. In a preliminary test, the system was used to classif' synchronous UV-vis fluorescence spectra ofrelatively similar petroleum oils with reasonable success.
Isovector and Gamow-Teller Strength from Small-Angle (n, p) Reactions at 60 MeV

The ($n, p$) reactions to the analog giant magnetic dipole states, the inverse of the transitions in allowed Gamow-Teller $\ensuremath{\beta}$ decay, have been measured for $^{6}\mathrm{Li}$, $^{12}\mathrm{C}$, and $^{28}\mathrm{Si}$ for forward angles using 59.6-MeV neutrons. With use of a relation between $\ensuremath{\sigma}(0\ifmmode^\circ\else\textdegree\fi{})$ and the $\ensuremath{\beta}$-decay matrix elements, there results ${{v}_{\ensuremath{\sigma}\ensuremath{\tau}}}^{c}(0)=157\ifmmode\pm\else\textpm\fi{}11$ MeV ${\mathrm{fm}}^{3}$ for the $l=0$, isovector part of the effective spin-flip nucleon-nucleon interaction. Comparison with 120-MeV ($p, n$) reactions indicates that ${{v}_{\ensuremath{\sigma}\ensuremath{\tau}}}^{c}$ has a small energy dependence in the range 60 to 120 MeV.
Compartment syndrome of the leg in the coagulopathic, end-stage liver disease patient: Fasciotomy is not the best answer.

Abstract Background Compartment syndrome of the leg secondary to spontaneous bleeding has been described in coagulopathic patients. Correction of the coagulopathy and emergency fasciotomy is the recommended treatment. We present a cirrhotic patient with a short life expectancy who developed compartment syndrome of the leg secondary to spontaneous bleeding. This patient underwent fasciotomy of the leg and subsequently developed persistent postoperative bleeding and required repeated transfusions of blood and blood products. The patient eventually expired in the hospital 1 month after surgery. Results Compartment syndrome of the leg occurring in patients with coagulopathy secondary to cirrhosis is very difficult to manage. Coagulopathy in these patients is hard to correct and constant bleeding from fasciotomy site is a major complication mandating frequent transfusions of blood and blood products. The complications of fasciotomy in these patients may outweigh the complications of untreated fasciotomy, particularly in patients with a short life expectancy. Conclusions Fasciotomy is not always the best treatment for compartment syndrome of the leg. In certain patients, particularly in the coagulopathic, end-stage cirrhotic patient with a short life expectancy who is not a candidate for liver transplantation, fasciotomy is not indicated. Fasciotomy should be used selectively, if at all, in patient population with end-stage and terminal diseases.
Stability of the ordinary mode to an electron heat flux.

Stability equations for the low frequency ordinary mode propagating perpendicular to a homogeneous magnetic field in the presence of a heat flux in a collisionless plasma are derived by working within an appropriate velocity reference frame. Solutions indicate the ordinary mode is stable under average solar wind conditions at 1 AU.
Delayed nidation in the rat induced by autografts of the hypophysis with a case report of "asynchronous implantation".

A delay in nidation of embryos lasting 3 to 18 days was obtained by autografting the anterior pituitary gland to the kidney in rats on the 2nd day of pregnancy. Ovo-implantation was induced in these rats at will, by the daily injection of 1 μg of estrone. Implantation only rarely occurred, and it was followed immediately by death of the embryos in rats hypophysectomized on the 2nd day of pregnancy and treated daily with 4 mg of progesterone and 1 μg of estrone starting the 9th day of pregnancy; it never occurred when treatment was not started until the 14th day. The daily use of 1 μg of estrone in lieu of the progesterone-estrone treatment starting on the 9th day or 14th day of pregnancy failed to induce nidation in hypophysectomized untreated rats. A case of implantation of 1 embryo previous to estrone treatment and nidation of 8 additional embryos after the estrone in a rat bearing a pituitary autograft is reported. It is proposed that this phenomenon be called “asynchronous implantation” rather than th...
Efficacy of Chest Radiography in a Respiratory Intensive Care Unit: A Prospective Study

A prospective study of chest radiographic examinations in a respiratory intensive care unit was conducted to determine the diagnostic and therapeutic efficacy of such examinations. Analysis of data from 1,354 x-ray films from 167 patients revealed a 34.5 percent incidence of new (or increased) abnormalities, or tube or catheter malposition. Changes in diagnostic approach or therapeutic measures, excluding catheter position adjustments, occurred after 28.5 percent of the examinations. Radiographic yield was higher when a change in clinical condition prompted the radiographic examination than when the examination was a routine morning study. Changes in the approach to patient management were also more likely (42.7 percent) following examinations that were prompted by a change in a patient's clinical status. Less than 6 percent of the radiographic films taken post-procedure demonstrated abnormalities potentially related to the procedure. We conclude that, in a respiratory intensive care unit: 1) routine morning radiographic examination frequently demonstrates unexpected or changing abnormalities, many of which prompt changes in diagnosis or management; 2) radiographic evaluation of a change in a patient's clinical condition has a higher yield than routine examinations; and 3) post-procedure radiographic examination uncommonly demonstrates complications related to the procedure, but frequently demonstrates abnormalities of tube or catheter placement.
Rate constants for reaction of a fluorous tin hydride reagent with primary alkyl radicals

Abstract Rate constants for 6-exo cyclization of the 7,7-diphenyl-6-heptenyl radical (3) in benzotrifluoride (BTF, PhCF3) were determined by laser flash photolysis, and radical clock 3 was used in competition kinetic studies for determination of rate constants of reactions of the fluorous tin hydride reagent tris(2-(perfluorohexyl)ethyl)tin hydride with primary alkyl radicals.
Identification of an Amino Acid Residue That Lies between the Exofacial Vestibule and Exofacial Substrate-binding Site of the Glut1 Sugar Permeation Pathway

A valine-to-isoleucine mutation at amino acid residue 197 of Glut2 or the equivalent residue 165 of Glut1 has been shown to impair glucose transport activity. This mutation was originally discovered in the Glut2 gene of a patient with type 2 diabetes. We investigated the mechanism of the effect of this mutation on transport activity via the analysis of Glut1 mutants expressed in Xenopus oocytes combined with cysteine substitution mutagenesis and the use of cysteine-reactive chemical probes. Aliphatic side chain substitutions at position 165 that were bulkier than the native valine residue inhibited glucose transport activity, whereas substitutions of less bulky side chains had little effect on transport, suggesting a role for steric hindrance. A cysteine residue was introduced at position 165 of a functional, cysteine-less Glut1 construct, and this mutant was then tested for inhibition of transport activity by a membrane-impermeant sulfhydryl-specific reagent (p-chloromercuribenzenesulfonate). p-Chloromercuribenzenesulfonate inhibited activity of the Cys165 mutant when it was added to the external buffer but not when it was injected directly into oocytes, indicating that this residue is accessible from the external solvent but not from the cytoplasm. Competition experiments indicated that Cys165 lies near the exofacial substrate-binding site or directly in the sugar permeation pathway. These data provide evidence that the side chain of Val165, which resides in the middle of transmembrane helix 5, juts into the aqueous permeation pathway of Glut1, probably between the exofacial substrate-binding site and the outer vestibule of the pathway.
The complexity of the membership problem for some extensions of context-free languagest†

The time and tape complexity of some families of languages defined in the literature by altering methods of generation by context-free grammars is considered. Specifically; it is shown that the following families of languages can be recognized by deterministic multitape Turing machines either in polynomial time or within (log n)2 tape: 1) the context independent developmental (EOL) languages; 2) the simple matrix languages; 3) the languages generated by derivation restricted state grammars.: 4) the languages generated by linear context-free grammars with certain non-regular control sets; 5) the languages generated by certain classes of vector grammars. In fact, these languages are of the same tape complexity as context-free languages. Other results indicate the complexity of EDOL languages and the effects on complexity of applying the homomorphic replication operator to regular and context-free languages.
Hepatic injury in chronic iron overload. Role of lipid peroxidation.

In both hereditary hemochromatosis and in the various forms of secondary hemochromatosis, there is a pathologic expansion of body iron stores due mainly to an increase in absorption of dietary iron. Excess deposition of iron in the parenchymal tissues of several organs (e.g. liver, heart, pancreas, joints, endocrine glands) results in cell injury and functional insufficiency. In the liver, the major pathological manifestations of chronic iron overload are fibrosis and ultimately cirrhosis. Evidence for hepatotoxicity due to iron has been provided by several clinical studies, however the specific pathophysiologic mechanisms for hepatocellular injury and hepatic fibrosis in chronic iron overload are poorly understood. The postulated mechanisms of liver injury in chronic iron overload include (a) increased lysosomal membrane fragility, perhaps mediated by iron-induced lipid peroxidation, (b) peroxidative damage to mitochondria and microsomes resulting in organelle dysfunction, (c) a direct effect of iron on collagen biosynthesis and (d) a combination of all of the above.
A second-order condition that strengthens Pontryagin's maximum principle

Abstract We derive a second-order necessary condition for optimal control problems defined by ordinary differential equations with endpoint restrictions. This condition, based on a second-order restricted minimization test, bears a somewhat similar relation to the Weierstrass E -condition (the Pontryagin maximum principle) as the Legendre and Jacobi conditions bear to the Euler-Lagrange equation. Specifically, in the context of relaxed controls, the E -condition for free endpoint problems asserts that if a function achieves its minimum over a convex set Q at some point q then its one-sided directional derivatives at q into Q are nonnegative. Our new condition, when applied to the special case of free endpoint problems, corresponds to the observation that if such a one-sided directional derivative at q is 0 then the corresponding second directional derivative is nonnegative. This new condition effectively supplements the Pontryagin maximum principle over the singular regimes of “weakly” normal extremals that are candidates for either a relaxed or an ordinary restricted minimum. Like some other second-order methods, this condition is global over the control set but, unlike the other tests, it is also global over time. A number of examples illustrate its use and behavior.
Electronic Mail as a Vehicle for Peer Response: Conversations of High- and Low-Apprehensive Writers.

This Qualitative study sought to determine whether four high- and four low-apprehensive first-year college writers responded differently as peer evaluators of writing in a face-to-face group versus a group that communicated via an electronic-mail network. An analysis of recorded group “conversations” revealed that high apprehensives exhibited different strategies than low apprehensives for informing group members about writing during both face-to-face and e-mail sessions. Furthermore, high apprehensives during e-mail sessions participated more and offered more directions for revision than during face-to-face meetings. When revising subsequent to group meetings, high apprehensives reported relying more on group comments received during e-mail sessions than group comments received during face-to-face sessions.
Ethanol-induced contraction of cerebral arteries in diverse mammals and its mechanisms of action

Abstract Acute ethanol exposure (8–570 mM) induced potent contractile responses of rings in both basilar and middle cerebral arteries, from dogs, sheep, piglets and baboons, in a dose-dependent manner. The contractions were reproducible and not tachyphylactic. The middle cerebral arteries were found to be more sensitive to ethanol than the basilar arteries. No known pharmacological antagonist, tested, exerted any effects on ethanol-induced contractions. No differences in responsiveness to ethanol in canine cerebral arteries were found between male and female animals or between the presence and the absence of endothelial cells. Removal of extracellular Ca2+ ([Ca2+]o) partially attenuated ethanol-induced contractions, while withdrawal of extracellular Mg2+ ([Mg2+]o) potentiated such contractions. In the complete absence of [Ca2+]o, caffeine and ethanol induced similar, transient contractions followed by relaxation in K+-depolarized cerebral vascular tissue. Ethanol-induced contractions were completely abolished by pretreatment of tissues with caffeine. Our results suggest that: (a) acute ethanol intoxication can induce direct contractions (independent of amine, prostanoid or opioid mediation) of diverse mammalian cerebral vascular tissues, including those from primates; (b) these contractile responses are heterogenous along the cerebrovascular tree and independent of endothelial cells; (c) in addition to a need of [Ca2+]o, an intracellular release of Ca2+ is needed for ethanol to induced contractions; and (d) hypomagnesemia or Mg deficiency potentiates the contractile effects of ethanol on brain vessels and may be a risk factor for ethanol-related, ischemic stroke events.
Substrate-attached glycoproteins mediating adhesion of normal and virus-transformed mouse fibroblasts.

When BALB/c 3T3, simian virus 40 (SV40)-transformed 3T3 (SVT2), and revertant variants of the transformed cells are removed by EGTA treatment from the substrate on which they were grown, they leave behind a layer of glycoprotein which has been characterized biochemically (Terry, A. H. and L. A. Culp. 1974. Biochemistry. 13:414.)—substrate-attached material (SAM). The influence of SAM from normal and from transformed cells on cellular attachment to the substrate, morphology, movement, and growth has been examined. All three cell types displayed a 30% higher plating efficiency when grown on 3T3 SAM. The morphology of SVT2 colonies and of individual SVT2 cells was dramatically affected by growth on 3T3 SAM—the cells (a) were more highly spread on the substrate, (b) resisted crawling over neighboring cells, and (c) resisted movement away from the edge of colonies; SVT2 SAM was not effective in causing these changes. A cell-to-substrate attachment assay using thymidine-radiolabeled cells and untreated or SAM-coated cover slips was developed. SVT2 cells attached to 3T3 SAM- or SVT2 SAM-coated cover slips with a faster initial rate and to a higher saturation level than to untreated substrate, whereas 3T3 and revertant cells exhibited no preference; there was no species specificity in these cell-substrate attachment phenomena. Trypsin-released cells attached much more slowly than EGTA-released cells. 3T3 SAM, however, was not effective in lowering the saturation density of mass cultures of virus-transformed cells. These experiments suggest that the substrate-attached glycoproteins of normal cells affect the cellular adhesivity, morphology, movement, and perhaps growth patterns of virus-transformed cells—i.e., causing partial reversion of these properties of transformed cells to those found in contact-inhibited fibroblasts. A model for the involvement of substrate-attached glycoproteins in cell-to-substrate adhesion, and possibly cell-to-cell adhesion, has been proposed.
Ratio of variance to mean of action potential counts for an auditory nerve fiber model with second‐order refractory behavior

Sequences of interval times were generated with the first‐ and second‐order interval probability dependence proposed by Gaumond et al. [J. Neurophysiol. 48, 856–873 (1982)] to characterize cochlear nerve fiber spontaneous action potential (AP) sequences. The ratio F(T) of the variance to the mean of the count of APs in bins of T s was computed for the simulated sequences, and compared to the corresponding measure for cochlear nerve fiber data presented by Lowen and Teich [J. Acoust. Soc. Am. 92, 803–806 (1992)]. The simulations were generally consistent with the data in the range 15<T<100 ms.
Cardiac lineage selection: integrating biological complexity into computational models

The emergence of techniques to study developmental processes using systems biology approaches offers exciting possibilities for the develpmental biologist. In particular cardiac lineage selection may be particularly amenable to these types of studies since the heart is the first fully functional organ to form in vertebrates. However there are many technical obstacles that need to be overcome for these studies to proceed. Here we present a brief overview of cardiomyocyte lineage deterimination and discuss how different aspects of this process either benefit from or present unique challenges for the development of systems biology approaches. Copyright © 2009 John Wiley & Sons, Inc. For further resources related to this article, please visit the WIREs website.
Ion-Neutral Propulsion in Atmospheric Media

A basic theoretical and experimental investigation of an aerodynamic corona discharge propulsion system is presented. A one-dimensional, constant-area analytical model with multiple point, space-charge-limited emission of negative ions is considered. Explicit relations expressing performance are derived for this system. Experimental results verify the validity of the theoretical expressions and indicate that the energy conversion efficiency leading to propulsion is approximately 1%. The experiments further indicate that the remaining energy manifests itself in the form of heat. Ion mobility is found to be the most decisive factor in determining system performance. Results suggest that future studies should be directed toward lowering the effective ion mobility to achieve an acceptable level of propulsive power efficiency.
Preoperative Cessation of Smoking and Pulmonary Complications in Coronary Artery Bypass Patients

La reduction des complications pulmonaires apres au moins 2 mois d'interruption de fumer est en rapport avec l'amelioration de la fonction ciliaire et des voies aeriennes et une diminution de la production d'expectoration
Technique and use of supine oblique views in acute cervical spine trauma

Study objective: To determine whether the addition of the supine oblique view of the cervical spine can detect fractures or ligamentous injury not seen on the standard three-view examination. Design: Radiographs of patients with documented cervical spine injury were reviewed retrospectively by three neuroradiologists. Patients were included in the study if the initial interpretation of the three-view series was normal and the abnormal supine oblique view enabled a correct diagnosis to be established. Setting: The emergency department of a university-affiliated hospital with Level I trauma center status. Type of participants: Eighty-three consecutive patients with documented cervical spine injury evaluated during a 20-month period. Results: Eight patients demonstrated abnormality to best advantage on the supine oblique view. These included six fractures and two ligamentous injuries. Five patients had abnormalities confined to the supine oblique view, and the remaining three had subtle abnormalities on the cross-table lateral view. Conclusion: The supine oblique view may detect fractures or ligamentous injury not identifiable on the standard three-view examination. We recommend the routine use of a five-view cervical spine series with the inclusion of 30-degree supine oblique views in the evaluation of acute cervical spine injury.