cssi/SciSciGPT-SciSciNet huggingface dataset:
Physical Principles of Protein Crystallization

Publisher Summary This chapter discusses various aspects of the physical chemistry of protein crystal growth. Proteins are crystallized from aqueous solutions using methods that have been extensively studied for simpler molecules and salts. Proteins typically appear to be able to form crystals over a fairly large range of solution conditions. However, conditions required to produce large ordered crystals occupy a smaller fraction of the total crystallization parameter space. Stochastic events are important in protein crystallization. Solution fluctuations provide the driving force for homogeneous nucleation in supersaturated solutions. Effects are amplified in the small solution volumes used in vapor diffusion experiments, where high surface area volume ratios produce transient concentration gradients. Temperature and vibration are important factors in controlling crystal nucleation and growth. Solution parameters change during crystal growth. The bulk protein concentration decreases as crystals grow, while the concentration of impurities increases. Many crystallization reports emphasize the need to use pure proteins to ensure crystal reproducibility. Changes in a single experimental parameter can simultaneously influence several aspects of a crystallization experiment. The interaction of parameters makes it difficult to design experiments to isolate individual effects and likewise complicates the interpretation of experimental results.
Drinking Water and Public Health Protection

The provision of drinking water for communities is an urban utility, but a utility with a difference. As with other urban utilities, such as electricity and gas, water for household use is a necessity that cannot readily be obtained by urban householders for themselves. The difference is that, while water may satisfy many household needs, including drinking, it has the potential of spreading disease, often without the knowledge of the consumer. As a result, water supplies have become subject to regulations for assuring adequate quality, regulations that are not faced by other municipal public utilities. Beginning with the water supply for Rome some 2000 years ago, the responsibility for water supply and its quality rested with the community. During the nineteenth century, with the beginning of the industrial era and the rapid growth of cities, public water supplies began to be provided by private entrepreneurs who sought profit in providing an essential service, frequently in competition with others. In the interest of getting a larger share of the market, they might provide a water of better quality than a competitor. Keywords: urban utility; transmission lines; filtration; chlorination; rome; industrial revolution; Dr. John Snow; Bronx River; croton aqueduct; Dr. Abel Wolman; turbidity; safe drinking water act; bureau of water hygiene; public water supply
Utility of preprocedure checklists in the congenital cardiac catheterization laboratory.

Objective Preprocedure meetings have become more commonplace in medicine but are not performed routinely in the cardiac catheterization laboratory. We sought to create, implement, and evaluate a preprocedural meeting in the form of a checklist for the cardiac catheterization laboratory. Staff attitudes and perceptions toward safety and sense of teamwork were also analyzed. Design All procedures performed in the cardiac catheterization laboratory on patients with structural heart disease from January 2010 to February 2012 were retrospectively reviewed for demographics, procedural details, and reported complications. A checklist was introduced to the preprocedure protocol at the halfway point, and patients were divided into pre- and postchecklist cohorts. Anesthesia and cardiac catheterization laboratory staff were surveyed at the beginning and end of the study period regarding attitude toward safety, team climate, and the impact of errors. Results Total number of procedures (prechecklist, n = 371; postchecklist, n = 370) and demographics were similar among groups. Complication rates were equivalent pre- and postchecklist, but there was a greater proportion of interventional cases and higher median complication level in the postchecklist group. Cardiac catheterization laboratory staff reported improved awareness of being briefed with the checklist. Anesthesia differed from cardiac catheterization staff in perception of communication as well as team and safety climate. Conclusions A preprocedure checklist for congenital cardiac catheterization cases is easy to perform and serves to update cardiac catheterization laboratory staff. Anesthesia and cardiac catheterization staff had different perceptions of safety and teamwork climate. Further studies are needed to determine if this briefing could lead to better communication among services and ultimately reduce complications.
Energy Requirement for l-Glutamate Uptake and Utilization by Hansenula subpelliculosa Cells

Shieh, K. Z. (Illinois Institute of Technology, Chicago), and L. R. Hedrick. Energy requirement for l-glutamate uptake and utilization by Hansenula subpelliculosa cells. J. Bacteriol. 92: 1638–1644. 1966.—Cells of the yeast Hansenula subpelliculosa require an energy source for the uptake of glutamate. A lag period of 20 to 40 min was required after the addition of glucose to the cells before glutamate uptake was initiated. When cells were preincubated in glucose, and washed with distilled water prior to the addition of glutamate, there was no lag period. Preincubation in glucose and glutamate lowered both the rate and the total uptake of glutamate as compared with cells preincubated in glucose alone. This is attributed to the partial utilization of the glucose-metabolite by glutamate or to the partial saturation of binding sites by glutamate during the preincubation period. Transport of glutamate by these yeast cells appears to be via a carrier, where energy is required for the binding of the amino acid to nonspecific binding sites. In addition to total uptake, some aspects of the C 14 -glutamate utilization were measured. Of the total uptake, 58% was metabolized and converted to CO 2 , 25.2% remained in the soluble pool, and 16.8% was incorporated into trichloroacetic acid-insoluble products. When the available energy source was depleted, the processes of uptake, metabolism, and incorporation ceased, even though there was an ample supply of glutamate present within the cells. Removal of cells from glutamate and addition of glucose reinitiated the incorporation of glutamate into proteins and other trichloroacetic acid-insoluble compounds. Therefore, an additional energy source is required with this species of yeast for glutamate uptake, for the priming of mechanisms required for its metabolism, and for its incorporation.
Harmonics elimination and distribution using decentralized control for microgrid applications

Decentralized control of a new harmonics distribution method for microgrid is presented in this paper. The compromise between voltage regulation at point of common coupling (PCC) and harmonics sharing is provided. The control algorithm that optimizes microgrid performance regarding these two factors is proposed and its implementation is described. The effect of small error in coupling impedance estimation and a way to resolve the problem is presented. The simulation and experimental results for the proposed configuration are provided.
Flux concentrators in integrating sphere experiments: potential for increased detector signal.

Concentrators yield no increase in collected flux over bare detectors in integrating sphere applications where a large field of view is allowed but can provide meaningful increases in signal when the field of view must be limited. The correct concentrator to use is elliptical rather than parabolic. In calculations of sphere efficiency and correction factors, the detector–concentrator assembly should be treated as if it were the detector alone.
Morphology of Poly-L-alanine Spherulites

Geil1 and Keith and Padden2 prepared small spherulites and hedrites of poly-L-alanine. We have now studied the morphology and structure of such spherulites of larger size and much greater perfection which were formed in essentially 100 per cent yield by casting poly-L-alanine (40 mg) from solution (4 ml.) of trifluoroacetic acid and trifluoroethanol (1:1 v/v). The solvent was allowed to evaporate very slowly (1 ml./12 h) at room temperature from a large watch glass.
Water-Soluble Flavor and Odor Precursors of Meat. 3. Changes in Nucleotides, Total Nusleosides and Bases of Beef, Pork and Lamb During Heating

SUMMARY: Studies were made of the influence of heating on nucleotides and total purine nucleosides and bases of beef, pork and lamb muscle. lnosinic acid was the predominant nucleotide in all three species and it was degraded by heating. Adenylic acid increased during cooking in meat from all three species. Cytidylic, uridylic and guanylic acids were present in relatively low concentrations in meat from all three species and changed little during cooking. A rapid method for estimating total nucleotides resulted in greater variation than a specific method for measuring individual nucleotides.
Creating Small Unit Cohesion: Oliver Hazard Perry at the Batte of Lake Erie:

While historians and social scientists emphasize the role of unit cohesion in battlefield success, they generally avoid the examination of how unit cohesion has been created. This article examines the battle of Lake Erie, 10 September 1813, in light of unit cohesion criteria. It concludes that while Master Commandant Oliver Hazard Perry and his captains created "vertical cohesion" (bonding between leaders and subordinates) within their respective crews, the self-identification of the value of intergroup cooperation between the various captains and their commodore was never fully actuated. Despite his faults, the article argues that Perry justifiably deserves the reputation of the creator of unit cohesion under difficult circumstances.
The MAPI method—Its effects on productivity: An alternative is needed

Abstract This paper examines the question of whether “cookbook” methods of equipment replacement and capital investment analysis have had an adverse effect on productivity. The MAPI method is scrupulously examined for this purpose. It is shown that MAPI is constructed around some rather binding assumptions that cannot be considered as valid in today's economic environment. A more traditional approach is advocated in this paper that will provide more accurate and reliable measures than MAPI. The proposed method requires that economic service lives be determined for all alternatives and an Annual Worth (AW) analysis be performed on each competing project's aftertax cash flow.
Reversible aryl C–H bond activation in the reaction between HRu3(CO)9,10(μ-PPh2) and the diphosphine ligand 4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione (bpcd): X-ray diffraction structures of H2Ru3(CO)7(bpcd)[μ,σ-PPh(C6H4)] and Ru3(CO)6(μ-CO)(μ-PPh2)[μ,η2,η1-PPhCC(PPh2)C(O)CH2C(O)]

Abstract The reaction between HRu3(CO)10(μ-PPh2) (1) and the diphosphine ligand 4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione (bpcd) proceeds rapidly in the presence of Me3NO to furnish H2Ru3(CO)7(bpcd)[μ,σ-PPh(C6H4)] (3). Treatment of the nonacarbonyl cluster HRu3(CO)9(μ-PPh2) (2) with bpcd at room temperature affords cluster 3 as the major product in addition to cluster 1. Thermolysis of cluster 3 in 1,2-dichloroethane yields Ru3(CO)6(μ-CO)(μ-PPh2)[μ,η2,η1-PPhC C(PPh2)C(O)CH2C(O)] (4) as the major isolable product. The highlights associated with the production of cluster 4 involve the reductive elimination of the orthometalated aryl group with one of the two bridging hydrides in 3 and cleavage of one of the P–Ph bonds of the bpcd ligand, followed by the release of benzene from the transient sigma-bound Ru–Ph group. Both H2Ru3(CO)7(bpcd)[μ,σ-PPh(C6H4)] and Ru3(CO)6(μ-CO)(μ-PPh2)[μ,η2,η1-PPhC C(PPh2)C(O)CH2C(O)] have been isolated and characterized in solution by IR and NMR (31P and 1H) spectroscopies, in addition to X-ray crystallography. The solid-state structure of H2Ru3(CO)7(bpcd)[μ,σ-PPh(C6H4)] confirms the presence of an orthometalated μ2-phosphido moiety and a chelating bpcd ligand. The crystal structure of cluster 4 consists of a triangular Ru3 core where one face is capped by the 6e-donor ligand μ,η2,η1-PPhC C(PPh2)C(O)CH2C(O).
Evaluating the performance of a simple inductive procedure in the presence of overfitting error

The theory of uniform convergence extends the classical strong law of large numbers from a single real-valued function to an ensemble, or class, of such functions. Vapnik and Cervonenkis have characterized those classes of functions for which the uniform strong law holds. We refer to such classes as being uniformly convergent. The theory provides a powerful methodology with which one can establish the consistency of simple inductive procedures for a variety of statistical problems, including pattern recognition, density estimation and the training of neural networks. In practical situations, however, we may not have sufficient information determine by analytical means whether or not a particular class of functions is uniformly convergent.
Hidden phase effects in estimating the minimum-variance pupil plane field of a coherently illuminated far-field object

Recently, it has been shown that least squares phase estimators require the determination of a hidden phase to properly reconstruct a field that contains branch points. The branch points, resulting from zeros in the complex field, occur at random locations. These branch points introduce discontinuities in the 2D phase function that have a magnitude of 2(pi) . Conventional least squares and minimum variance phase reconstructors do not properly sense these discontinuities and therefore have difficulty in reconstructing the field resulting from a coherently illuminated object. Preliminary investigations are made in determining the utility of the hidden phase to the minimum variance based phase reconstructors. A simple 2D image model is reconstructed using the hidden phase adjustments.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Infusion of CCK-A Receptor mRNA Antisense Oligodeoxynucleotides Inhibits Lordosis Behavior

Abstract Holland, K. L., P. Popper and P. E Micevych. Infusion of CCK-A receptor mRNA antisense oligodeoxynucleotides inhibits lordosis behavior. Physiol Behav 62(3) 537–543, 1997.—Cholecystokinin (CCK) acting on discrete receptors in the limbic-hypothalamic circuit modulates lordosis behavior. Neurons in the medial preoptic nucleus (MPN) express CCK-A subtype receptor mRNA, and site-specific infusions of CCK facilitate lordosis, suggesting that CCK-A receptor activation positively modulates lordosis. In the present study, we demonstrated CCK binding in the central portion of the MPN (MPNc) and the disruption of lordosis behavior by reducing the expression of CCK-A receptors in this nucleus. Antisense oligodeoxynucleotides (ODN) specific for CCK-A receptor mRNA were infused into the MPN of ovariectomized female rats. The expression of estrogen-induced lordosis behavior was blocked in animals receiving infusions of antisense ODN into the MPN (LQ = 10.0 ± 1.0) compared to animals receiving infusions of nonsense ODN (containing the same nucleotide bases in a random order; LQ = 92.5 ± 7.5). In vitro, AR42J pancreatic acinar carcinoma cells treated with antisense ODN had lower levels of CCK-A and CCK-B subtype receptor binding than nonsense ODN treated cells. In vivo, however, infusions of CCK-A mRNA antisense ODN did not alter CCK-B receptor binding levels. These results suggest that CCK, acting via CCK-A receptors in the MPNc, is critical for the display of lordosis behavior.
Preparation of thin film GaAs on glass by pulsed-laser deposition

ABSTRACT One of the most straightforward methods possible is presented and investigated to form thin film GaAs. The film was deposited on unheated glass in vacuum (10 -6 Torr) by the ablation from a GaAs wafer with the emission of a pulsed Nd:YAG laser (532 nm, 6 ns, 10 Hz). The photoluminescence, photocurrent, transmission and micro-Raman measurements of the films demonstrate that films with promising optoelectronic properties have been formed. Most importantly, from the viewpoint of light emitting and optoelectronic device production, the films show photoluminescence of comparable intensity with the bulk material without emissions owing to impurities, although the films show a rather flat absorption edge which indicates tail states. The observed photocurrent was in the µ A/W range driven by rather moderate electric fields on the order of 100 V/cm. Concerning the material quality, the films have an extremely smooth surface as demonstrated with scanning electron microscopy. Grown GaAs films on glass substrates were amorphous evidenced by X-ray diffraction measurements, however, micro-Raman measurements showed crystalline phonon modes, suggesting that localized crystalline structure might co-exist in amorphous GaAs films. Keywords: Thin film GaAs, pulsed-laser deposition, photoluminescence, photocurrent, transmission, X-ray diffraction Raman spectroscopy
Mutation of Aspartate 555 of the Sodium/Bicarbonate Transporter SLC4A4/NBCe1 Induces Chloride Transport.

To understand the mechanism for ion transport through the sodium/bicarbonate transporter SLC4A4 (NBCe1), we examined amino acid residues, within transmembrane domains, that are conserved among electrogenic Na/HCO3 transporters but are substituted with residues at the corresponding site of all electroneutral Na/HCO3 transporters. Point mutants were constructed and expressed in Xenopus oocytes to assess function using two-electrode voltage clamp. Among the mutants, D555E (charge-conserved substitution of the aspartate at position 555 with a glutamate) produced decreasing HCO3− currents at more positive membrane voltages. Immunohistochemistry showed D555E protein expression in oocyte membranes. D555E induced Na/HCO3-dependent pH recovery from a CO2-induced acidification. Current-voltage relationships revealed that D555E produced an outwardly rectifying current in the nominally CO2/HCO3−-free solution that was abolished by Cl− removal from the bath. In the presence of CO2/HCO3−, however, the outward current produced by D555E decreased only slightly after Cl− removal. Starting from a Cl−-free condition, D555E produced dose-dependent outward currents in response to a series of chloride additions. The D555E-mediated chloride current decreased by 70% in the presence of CO2/HCO3−. The substitution of Asp555 with an asparagine also produced a Cl− current. Anion selectivity experiments revealed that D555E was broadly permissive to other anions including NO3−. Fluorescence measurements of chloride transport were done with human embryonic kidney HEK 293 cells expressing NBCe1 and D555E. A marked increase in chloride transport was detected in cells expressing D555E. We conclude that Asp555 plays a role in HCO3− selectivity.
Statistical issues of QT prolongation assessment based on linear concentration modeling.

The ICH (2005) defined drug-induced prolongation of QT interval, i.e., the duration of depolarization and repolarization of ventricles, as evidenced by an upper bound of the 95% confidence interval around the mean effect on QTc (QT corrected for heart rate) of 10 ms. Furthermore, it defined that a negative thorough QT/QTc study is one in which the upper bound of the 95% one-sided confidence interval for the largest time-matched mean effect of the drug on the QTc interval excludes 10 ms. This objective leads to the application of intersection-union tests by testing the mean difference between test treatment and placebo of QTc change from baseline at each of the matched time points at which the observations are collected. The nature of the higher false positive rate due to more observational time points leads to the concern of study efficiency. Based on the concept of clinical pharmacology, a concentration-response modeling approach is often adopted to assess the prolongation size of QTc interval induced by...
Mass loss and OH maser emission from Mira variables

The mass, radius, and luminosity of 26 Mira variables that are known OH sources of radio emission at 1612 MHz have been estimated. The time-independent solution of Salpeter's (1974) stellar-wind equation and a period-density relation are used to solve for basic stellar parameters, with the aid of the terminal expansion velocity of the OH maser cloud. Masses obtained from these calculations are consistent with other estimated values for masses of Mira variables. Good agreement is obtained when comparing the rate of mass loss as determined from Reimers's (1977) semiempirical relation with estimates of the mass-loss rate as deduced from theoretical models involving radiation pressure on grains. These calculations suggest a strong correlation between the mass-loss rate and the pulsation period. Arguments concerning the general properties of silicate grains from radiation-pressure-driven stellar-wind equations are discussed.
Temporal stability of the hemodynamics of cardiovascular reactivity.

Abstract Cardiovascular responses to a competitive reaction-time task were monitored in 13 male subjects tested twice, 3 months apart. The temporal stability of blood pressure responses was in line with previous reports. However, in this study impedance cardiography permitted the investigation of the hemodynamic adjustments underlying the observed blood pressure responses. Analyses revealed that cardiac output and total peripheral resistance responses displayed temporal stability, indicating that subjects' blood pressure responses on the two occasions were the result of similar hemodynamic responses. These data thus extend the literature by demonstrating that the hemodynamic response pattern itself represents a stable individual differences variable.
Clinical pathologic correlation of superficial corneal opacities in X-linked ichthyosis

X-linked ichthyosis is a relatively common oculodermal disorder. Characteristic corneal opacities are small punctate or filiform lesions and are located in the deep corneal stroma. In an unusual case, a 73-year-old man with X-linked ichthyosis and steroid sulfatase deficiency had superficial corneal opacities. The corneal opacities were granular in nature, involving the subepithelial and anterior stromal layers. The opacities resulted in irregular overlying corneal epithelium and were white-gray in color in direct illumination. Histopathologic and electron microscopic studies demonstrated abnormalities of the corneal epithelial basement membrane. The epithelial basement membrane was thickened with irregular extensions into Bowman's layers. Abnormal depositions of basement membrane protein were seen in the anterior stroma. These abnormalities may have resulted from increased production of basement membrane proteins by the corneal epithelium, resulting from hyperactive turnover of the basal layer.
Commentary on "Diagnosis of Alzheimer's disease: two decades of progress".

It was a special privilege to be associated with the early National Institute on Aging support for and development of Alzheimer’s Disease research, and, in particular, as soon as I arrived at NIA in 1983 to learn from Zaven Khachaturian, in much more detail than I had known before, the major challenges and opportunities. He and his associates made it clear that our Institute’s commitment must stress basic biological and pathologic research to produce clear definition of this disease plus steps that might be undertaken to prevent and control its manifestations. At NIA, we made Alzheimer’s disease research our highest priority for program development and increased funding. Highlights of the mid 1980s included a national conference focusing on the challenges, and the initiation of and funding for major Alzheimer’s Disease Research Centers in 10 universities as well as support in other settings. In the years since then, I, along with so many others, have followed the major progress in learning about the explicit characteristics of this disease— the molecular pathology, the resulting pathophysiologic changes, the clinical consequences in affected persons, and potential therapies. We can all appreciate the continued growth in support of research, by the NIA and other sources; the sustained commitment of leaders and teams in pursuing the many important lines of research; the development of clinical services and therapies; and the extensive awareness by the public at large of the importance of all of these efforts.
Prolonged hallucinations following a modest overdose of tripelennamine.

(1980). Prolonged Hallucinations Following a Modest Overdose of Tripelennamine. Clinical Toxicology: Vol. 16, No. 3, pp. 331-333.
Solidification Heat Transfer and Base Separation Analysis in the Casting of an Energetic Material in a Projectile

This paper investigates the problem of base separation in the casting of energetic materials in a projectile. Special challenges that arise in casting high Prandtl number energetic materials in projectiles of complex geometries are addressed. A comprehensive numerical model is developed by integrating finite volume and finite element methods to analyze the thermal and flow fields as well as the residual stresses. The predictions, which are confirmed by experimental measurements, suggest that sustenance of a linear temperature profile along the projectile axis can eliminate base separation, and also reduce residual stresses in the final casting.Copyright © 2005 by ASME
Effect of replacing alfalfa with panicled-tick clover or sericea lespedeza in corn-alfalfa-based substrates on in vitro ruminal methane production

Methane emissions from ruminant livestock contribute to total anthropogenic greenhouse gas emissions and reduce metabolizable energy intake by the animal. Condensed tannins (CT) are polyphenolic plant secondary compounds commonly produced by some perennial forage legumes that characteristically bind to protein, carbohydrates, and minerals. The degree to which CT may affect ruminant nutrition depends upon the concentration, structural composition, and biological activity of the CT. The objective of our experiment was to determine the effect of replacing alfalfa in a corn-alfalfa-based substrate with a legume containing CT on in vitro CH4 production and the dynamics of fermentation using an in vitro gas production technique. All fermented substrates contained 50% ground corn as the energy concentrate portion, whereas the forage portion (50%) of each diet was comprised of alfalfa (control) or some combination of alfalfa and sericea lespedeza (SL) or panicled-tick clover (PTC). Our treatments consisted of PTC or SL 15, 30, and 45, which corresponded with 15, 30, or 45% replacement of the diet (alfalfa component) with either PTC or SL. Substrates containing 45% PTC or SL reduced in vitro CH4 production. Treatments did not affect total gas production as compared with that of the control. Replacement of alfalfa with SL or PTC increased fermentable organic matter (FOM). The PTC treatment increased FOM by as much as 1.8% at the 45% replacement level, whereas FOM of SL 45 was increased by less than 1%. The replacement of alfalfa with PTC increased substrate nutritive value greater than replacement with SL. There were no correlations between any physicochemical constituent of the substrates and CH4 production. A combination of factors associated with the inclusion of PTC and SL contributed to the in vitro CH4 production, and CT in these forages was likely a major contributing factor. Further confirmation of these results on in situ or in vivo animal systems is required. If proven effective in an in vivo production scenario, replacement of commonly fed non-CT-containing legumes, such as alfalfa, with legumes containing CT might be a viable method to decrease the effect of animal agriculture on greenhouse gas production.
Severity of silent myocardial ischemia on ambulatory electrocardiographic monitoring in patients with stable angina pectoris: relation to prognostic determinants during exercise stress testing and coronary angiography.

Abstract The relation of silent ischemia in patients with stable angina to known predictors of severity of coronary disease on exercise stress testing and coronary angiography is poorly defined. This issue was therefore examined with use of Holter electrocardiographic (ECG) recordings, treadmill exercise tests and angiographic indexes in 102 patients (not taking antianginal therapy) and the results were compared with Holter and treadmill findings in 42 volunteers. A total of 159 ischemic episodes (90% silent) were identified during 2,503 h on Holter recording in 97 patients (mean duration per episode 22.7 ± 147 min; range 1 to 234). Holter recordings had a 92% specificity and an 80% positive predictive value, but a sensitivity of only 37% and a negative predictive value of 27% for coronary disease. Sixty-three patients (Group I) had no ischemia on Holter recording, 22 (Group II) had a cumulative duration of 1 to 60 min/24 h and in 12 (Group III) ischemia exceeded 60 min/24 h. There was no significant correlation between cumulative ischemia duration on Holter recording and exercise duration or time to ST segment depression on treadmill exercise. In general, the greater the number of coronary vessels involved and the higher the proximal coronary artery stenosis score, the greater the likelihood of ischemia and the longer the cumulative ischemia duration on Holter recording. Irrespective of the severity of coronary disease, in about 25% of Holter recordings in each angiographic category there were no ischemic episodes. The 12 patients in Group III (ischemia duration >60 min/24 h) had a 3-fold greater probability of having three vessel or left mainstem disease and a 4- to 7-fold greater probability of having a higher proximal segment coronary stenosis index (p
Affirmative action, duality of error, and the consequences of mispredicting the academic performance of african american college applicants

The implications of different potential affirmative action policies depend on three factors: selection rate from the applicant pool, base rate of qualified applicants, and accuracy of performance predictions. A series of analyses was conducted under various assumptions concerning affirmative action plans, causes of racial differences in average college admissions test scores, and racial differences in accuracy of performance predictions. Evidence suggesting a lower level of predictive accuracy for African Americans implies that, under a program of affirmative action, both proportionately more false positives (matriculated students who do not succeed) and proportionately more false negatives (rejected applicants who could have succeeded) will be found among African American applicants. Unless equivalent levels of predictive accuracy are achieved for both groups, no admission policy can be fair simultaneously to majority group applicants and African American applicants. © 2002 by the Association for Public Policy Analysis and Management.
Factors contributing to success and failure of femorotibial bypass grafts.

Femorodistal bypass grafting is an important technique in the armamentarium of vascular surgeons, and it has been found that the cost of such procedures justifies their performance in patients who have sustained critical ischemia. Graft material remains the most important factor in causation of graft failure, with all prosthetics having disadvantages when compared to the saphenous vein. In attempts to use biological materials, both bovine heterografts and human umbilical vein grafts have been seen to form aneurysms and undergo thrombosis. Meanwhile, many variations on the theme of prosthetic grafts have been tried and found wanting when used as bypasses from the femoral artery to the distal circulation. Among configurations tried have been polytetrafluoroethylene with and without external support; Dacron® in woven and knitted format, with or without internal and external velour; and combinations of these. As patency rates of these reconstructions have proven inferior to others using the saphenous vein, attempts have been made to extend the use of autogenous biologic material. Such attempts have included cephalic vein bypass grafts, short vein bypass grafts originating distal to the femoral artery, deep veins used as grafts, and the in situ bypass. Lately, it has been recognized that the in situ bypass, when compared to concurrent controls, shows no significant advantage to the popliteal level but is the technique of choice when distal anastomoses are at or distal to the midcalf. Compositesequential bypasses represent another technique developed to utilize the autogenous vein as a distal segment. While this has increased the rate of patency of distal bypass grafting, other aids to patency such as use of anticoagulants, antiplatelet agents, and adjunctive arteriovenous fistula have not. Dynamics of the coagulation system show an intrinsic change in patient status toward coagulation in the postoperative period, and although this factor is of some significance in causing early graft thrombosis, technical defects do not seem to play an important part. This review details some of these important causes of graft failure and places them in proper perspective.
The effects of glutamate receptor agonists on neurotensin release using in vivo microdialysis.

Abstract In the present study, extracellular concentrations of neurotensin were measured from the striatum, nucleus accumbens and the medial prefrontal cortex in the awake, freely moving rat. Using a highly sensitive solid phase radioimmunoassay, basal concentrations of neurotensin were 2–5 pg/sample. In each region, glutamate receptor agonists, N-methyl- d -aspartate (NMDA) and kainic acid, increased neurotensin release 2–3-fold. Preincubation with the Na+ channel blocker tetrodotoxin abolished the glutamate receptor agonist-induced increases except in the striatum following kainic acid infusion. These findings indicate that activation of glutamate receptors may indirectly stimulate neurotensin release.
Energy Efficient Residential Thermal Control With Wireless Sensor Networks: A Case Study for Air Conditioning in California

Residential thermostats are sensor-limited devices, but low-cost wireless sensor network technology is enabling new spatially distributed sensing capabilities. This paper evaluates the energy and comfort performance of three multi-sensor control strategies that use wireless temperature and humidity sensors in each room and that can be applied to existing on-off residential central systems. The multi-sensor control strategies adjust the temperature set point of a thermostat to control the average of all room temperatures using a temperature threshold logic, minimize aggregate discomfort of all rooms, or maximize the number of rooms within a comfort zone. The strategies were tested using a custom wireless sensor network control system in a seven room, 2,100 square foot single-story house located in Pleasanton, CA during August and September. Performance was benchmarked against an implementation of a single-sensor constant temperature set point control logic using the custom control system and against a constant temperature set point using the original thermostat. Results show multi-sensor strategies may produce simultaneous improvements in energy consumption, room-to-room temperature distributions, and average comfort, compared to the single-sensor constant temperature set point threshold logic.Copyright © 2008 by ASME
Synthesis of Methylphosphonic Acid by Marine Microbes: A Source for Methane in the Aerobic Ocean

Relative to the atmosphere, much of the aerobic ocean is supersaturated with methane; however, the source of this important greenhouse gas remains enigmatic. Catabolism of methylphosphonic acid by phosphorus-starved marine microbes, with concomitant release of methane, has been suggested to explain this phenomenon, yet methylphosphonate is not a known natural product, nor has it been detected in natural systems. Further, its synthesis from known natural products would require unknown biochemistry. Here we show that the marine archaeon Nitrosopumilus maritimus encodes a pathway for methylphosphonate biosynthesis and that it produces cell-associated methylphosphonate esters. The abundance of a key gene in this pathway in metagenomic data sets suggests that methylphosphonate biosynthesis is relatively common in marine microbes, providing a plausible explanation for the methane paradox.
A model for thinning of the plasma sheet

Abstract A one-dimensional model for thinning of the plasma sheet is developed on the basis of launching a fast mode MHD rarefaction wave propagating in the tailward direction along the plasma sheet. Behind the rarefaction wave the pressure is reduced, leading to thinning of the plasma sheet and also to an Earthward plasma flow with a speed on the order of the sound speed a 0 . The plasma sheet thickness is reduced by a factor of 2 if an Earthward plasma flow speed of 0.8 a 0 is induced. The predictions of the model are in reasonable agreement with observations.
Transforming Growth Factor-β1 Stimulates Chondrogenic Differentiation of Posterofrontal Suture-Derived Mesenchymal Cells In Vitro

BACKGROUND Evidence from animal studies has associated transforming growth factor (TGF)-beta signaling with both normal and premature cranial suture fusion. However, the mechanisms whereby this pleiotropic cytokine mediates suture fusion remain uncertain. The authors established cultures of suture-derived mesenchymal cells from normally fusing (posterofrontal) and patent (sagittal) sutures and examined the in vitro effects of TGF-beta1 on these distinct cell populations. METHODS Skulls were harvested from 80 5-day-old mice. Posterofrontal and sagittal sutures were dissected, and cultures of suture-derived mesenchymal cells were established. The mitogenic, osteogenic, and chondrogenic effects of recombinant TGF-beta1 were then assessed on posterofrontal and sagittal suture-derived mesenchymal cells (1 to 10 ng/ml). Quantitative real-time polymerase chain reaction was used to examine the effects of TGF-beta1 on gene expression. RESULTS TGF-beta1 significantly decreased proliferation of both posterofrontal and sagittal suture-derived mesenchymal cells, by bromodeoxyuridine incorporation assays (n = 6). TGF-beta1 also inhibited osteogenesis in both suture-derived mesenchymal cells determined by alkaline phosphatase activity and mineralization (n = 3 for all assays). During chondrogenic differentiation, TGF-beta1 markedly increased expression of chondrocyte-specific gene markers in posterofrontal suture-derived mesenchymal cells (Sox9, Col II, Aggrecan, and Col X) (p <or= 0.05). In contrast, TGF-beta1 did not increase chondrocyte-specific gene expression in sagittal suture-derived mesenchymal cells (n = 3). CONCLUSIONS Posterofrontal suture-derived mesenchymal cells retain significant capability for both osteogenic and chondrogenic differentiation in vitro. TGF-beta1 induces in vitro chondrogenesis in posterofrontal but not sagittal suture-derived mesenchymal cells. Future studies will focus on elucidating the mechanisms whereby TGF-beta signaling mediates chondrogenesis in posterofrontal suture-derived mesenchymal cells.
Complete maternal and fetal recovery after prolonged cardiac arrest

A case of complete maternal and fetal recovery after prolonged cardiac arrest from massive lidocaine overdose is presented. A 27-year-old woman at 15 weeks gestation had a complete neurologic recovery after 22 minutes of CPR, including 19 minutes of electromechanical dissociation and asytole, with normal fetal heart function and fetal motion confirmed by ultrasound immediately after resuscitation. The patient delivered a healthy and neurologically normal infant at 40 weeks gestation. This is the longest cardiac arrest in early pregnancy reported in the medical literature with normal maternal and fetal outcome.
A crystal defect theory approach to micro-biomechanics.

Abstract This paper demonstrates the applicability of defect theory in crystal physics to the solution of problems in micro-biomechanics. We first introduce the concept of crystal imperfections with particular emphasis on the new defect known as dispiration. The presence of dispirations in the crystalline structures of T-even bacteriophages, tobacco mosaic viruses and striated muscles as well as the relation of dispirations to movements and shape changes of these biological systems are discussed. Since the crystalline structures of T-even bacteriophages and tobacco mosaic viruses assume the form of hollow cylinders, the geometric characteristics of dispirations in cylindrical surface crystals are examined. It also has been shown that within the approximation of shell theory the complete elastic field of a dispiration dipole can be obtained by superimposing the solutions of two sets of dislocation dipoles. The stability of dispirations is examined from the energy considerations. The present solution of dispiration elastic field provides a basic analytical tool for the understanding of the contractile mechanisms in biological systems.
Estimating Local Information Trustworthiness via Multi-source Joint Matrix Factorization

We investigate how to estimate information trustworthiness by considering multiple information sources jointly in a latent matrix space. We particularly focus on user review and recommendation systems, as there are multiple platforms where people can rate items and services that they have purchased, and many potential customers rely on these opinions to make decisions. Information trustworthiness is a serious problem because ratings are generated freely by end-users so that many stammers take advantage of freedom of speech to promote their business or damage reputation of competitors. We propose to simply use customer ratings to estimate each individual source's reliability by exploring correlations among multiple sources. Ratings of items are provided by users of diverse tastes and styles, and thus may appear noisy and conflicting across sources, however, they share some underlying common behavior. Therefore, we can group users based on their opinions, and a source is reliable on an item if its opinions given by latent groups are consistent across platforms. Inspired by this observation, we solve the problem by a two-step model -- a joint matrix factorization procedure followed by reliability score computation. We propose two effective approaches to decompose rating matrices as the products of group membership and group rating matrices, and then compute consistency degrees from group rating matrices as source reliability scores. We conduct experiments on both synthetic data and real user ratings collected from Orbitz, Priceline and Trip Advisor on all the hotels in Las Vegas and New York City. Results show that the proposed method is able to give accurate estimates of source reliability and thus successfully identify inconsistent, conflicting and unreliable information.
Flat-sided rectilinear trough as a solar concentrator: an analytical study

Formulas are derived for the concentration factor and irradiance distribution at the base of the flat-sided linear trough. Performance is affected by the number of reflections the solar rays undergo before reaching the base, the cone apex angle, and the coefficient of reflection. Results are presented graphically in such a way that one can choose the optimum configuration, which is the minimum material required, to achieve a given concentration factor. Practical concentration factors range from 1.5 to 4 depending on the geometry and coefficient of reflection.
The Optimal Commons

Much of the work on problems of open-access and common-property natural resources has been focused on deducing and documenting the pathologies of inefficiency to which these resources are prone. Another important job has been deriving policy conclusions; the main one being, perhaps, that productivity will improve in proportion to the speed with which a change is made to individual, or something that behaves like individual, ownership. In making these prescriptions our kit bag of institutional forms contains depressingly few items; in fact, it contains just two: common and individual. We have a situation analogous to one we had in the 1950s, when all goods were divided into two types: private and public. But the space between these two goods types was soon filled in with an infinity of intermediate forms. It is only fair that we fill up the comparable space in the property institutions continuum.
Non-intrusive Critical System Event Recognition and Prediction in Cloud

The cloud computing platform provides an efficient and flexible way to offer services and computation facilities to users. However, reliability in the cloud is an important factor to measure the performance of a virtualized cloud computing platform. System failure, software failure, outside attacks, and mis-actions of virtual machines make the cloud computing platform unstable and unreliable. In order to avoid critical events affect reliability, resources, applications, and services can be scheduled around predicted failure and limit the impact. In the cloud computing platform, different virtual machines may generate number of system events. Events from different virtual machines can affect system stability together. Such mechanisms are especially important for cloud computing environment. In this paper, we propose a framework to recognize and predict system critical events that come from different virtual machines to increase system stability of cloud computing environment.
Mental Health Follow-Up among Adolescents with Suicidal Behaviors after Emergency Department Discharge

The objective of this study was to examine mental health follow-up patterns and need for additional urgent ED evaluation in adolescents discharged home from a pediatric ED after an evaluation for suicidal ideation or attempt. In the study, the parent or guardian of suicidal youth ages 11 to 18 years who were discharged from the pediatric ED were interviewed by telephone between 1 and 2 months following the initial visit and asked about their child's suicide risk, mental health follow-up, return ED visits, and previous mental health experiences. ED records were also examined for return visits. A parent or guardian of 100 suicidal adolescents was interviewed by telephone. Most (66%) successfully followed up with a mental health provider. Mental health follow-up was more likely in those with an existing psychiatric diagnosis (OR: 3.03 [95% CI: 1.02-9.05]). The majority of those that returned to the ED within 2 months of their initial evaluation for mental health reasons were admitted [92% (19/21)]. The odds of an ED return visit were increased by a prior inpatient psychiatric admission (OR: 5.23 [95% CI: 1.80-15.16]), and a suicide attempt immediately prior to the initial ED visit (OR: 4.87 [95% CI: 1.04-22.69]). Many suicidal youth who are discharged from the ED successfully follow up with an outpatient mental health provider. However, a significant number do return to the ED within 2 months and require inpatient psychiatric admission. Future ED based interventions should focus on adolescents who attempt suicide and those with a history of prior inpatient admission.
Vanadium catalysis of the oxidation of catechol amines, dihydroxyphenylalanine and 5-hydroxyindoles.

IN the course of an investigation of the mechanism of enzymatic oxidation of serotonin (5-hydroxytryptamine) by human serum1, we found that apparently identical chromatographic reaction products2 resulted when this oxidation was catalysed non-enzymatically by cupric ion. We became curious as to what extent transitional metals other than copper catalysed this reaction, and expanded our investigation to include a study of the relative catalytic effectiveness of 18 transitional elements in the oxidations of related compounds of biological interest.