cssi/SciSciGPT-SciSciNet huggingface dataset:
Single facility scheduling with multiple job classes

Abstract This paper considers a static single facility scheduling problem where jobs are divided into several mutually exclusive classes. The jobs in a given class need not be processed together. In addition to a known processing time for each job, there is a switching time involved which depends on the class of the job immediately preceding a job. A heuristic algorithm is proposed to find a minimum mean flow time schedule. The effectiveness of the proposed heuristic algorithm is empirically evaluated and found to indicate that the solutions obtained from this heuristic algorithm are often close to optimal.
Noble Markets : The Noble/Slave Ethic in Hayek's Free Market Capitalism

Friedrich A. von Hayek influenced many areas of inquiry including economics, psychology and political theory. This article will offer one possible interpretation of the ethical foundation of Hayek’s political and social contributions to libertarianism and free market capitalism by analyzing several of his important non-economic publications, primarily The Road to Serfdom, The Fatal Conceit, The Constitution of Liberty and Law, Legislation and Liberty. While Hayek did not offer a particular ethical foundation for free market capitalism, he argued consistently that free markets are liberating and, for the markets to be truly free and for individuals to participate freely in markets, they should be subject to little control. Beyond some very basic principles, such as the protection of private property, that enable the free market to function properly, individuals are both free to and required to determine their own ethical compass. The central question, then, is what are the ethical principles that underlie Hayek’s view of the successful organization and operation of a free market? If formal rules and regulations must be kept to a minimum, then ethical behavior is an individual choice as well as an important foundation for the self-regulating free market. This article will argue that one possible ethical foundation underlying Hayek’s libertarian justification for free market capitalism are Friedrich Nietzsche’s “will to power” and noble/slave ethics. This article will rely primarily on Nietzsche’s On The Genealogy of Morals, Beyond Good and Evil, Zarathustra, and the Will to Power.
Monte Carlo simulations of reactive pulsed laser deposition

The Direct Simulation Monte Carlo (DSMC) method for simulating rarified gasdynamics has been applied to the problem of pulses laser deposition. Both 1D and 2D axisymmetric simulations were carried out. In both, a source of silicon expands into the background gas of argon in the presence of a diffusely reflecting substrate. Density, temperature, and axial flow velocity for each species are computed as functions of position and time. Particle flux and energy incident on the substrate are also monitored as functions of time. The simulation results are in good agreement with experimental plume diagnostics and film growth rates vs. pressure data.
Effects of atomic diffraction on the collective atomic recoil laser

We formulate a wave atom optics theory of the Collective Atomic Recoil Laser, where the atomic center-of-mass motion is treated quantum mechanically. By comparing the predictions of this theory with those of the ray atom optics theory, which treats the center-of-mass motion classically, we show that for the case of a far off-resonant pump laser the ray optics model fails to predict the linear response of the CARL when the temperature is of the order of the recoil temperature or less. This is due to the fact that in theis temperature regime one can no longer ignore the effects of matter-wave diffraction on the atomic center-of-mass motion.
Standing crops of chironomidae and tubificidae in two desert reservoirs, Central Arizona

In the two desert reservoirs examined seasonal and spatial variations in both densities and biomasses of chironomid dipterans and tubificid oligochaetes were quite high, but mean values are comparatively low. Densities of both organisms were generally low in summer, larger in autumn, and highest in spring. Disjunct distribution of the two taxa was evident. Distribution of these animals with depth in these desert reservoirs is affected by hypolimnic oxygen depletion, food supply (Chlorophyll-a concentrations), lake morphology and perhaps by substrate composition and predator-prey interactions.
Calculation of localized molecular orbitals

Two techniques are presented for reducing the effort required to determine localized orbitals based on the energy or density criteria. The first, population weighted editing of the electronic repulsion integrals, reduces the effort required for each iteration of the localization procedure. The second, damping/extrapolation of the transformation matrix, reduces the number of iterations required to reach convergence. Numerical results are provided for methane and formaldehyde (for the editing method) and for carbon monoxide and boron fluoride (for the damping/extrapolation technique).
A nuclear 3'-5' exonuclease involved in mRNA degradation interacts with Poly(A) polymerase and the hnRNA protein Npl3p.

Inactivation of poly(A) polymerase (encoded by PAP1) in Saccharomyces cerevisiae cells carrying the temperature-sensitive, lethal pap1-1 mutation results in reduced levels of poly(A)+ mRNAs. Genetic selection for suppressors of pap1-1 yielded two recessive, cold-sensitive alleles of the gene RRP6. These suppressors, rrp6-1 and rrp6-2, as well as a deletion of RRP6, allow growth of pap1-1 strains at high temperature and partially restore the levels of poly(A)+ mRNA in a manner distinct from the cytoplasmic mRNA turnover pathway and without slowing a rate-limiting step in mRNA decay. Subcellular localization of an Rrp6p-green fluorescent protein fusion shows that the enzyme residues in the nucleus. Phylogenetic analysis and the nature of the rrp6-1 mutation suggest the existence of a highly conserved 3′-5′ exonuclease core domain within Rrp6p. As predicted, recombinant Rrp6p catalyzes the hydrolysis of a synthetic radiolabeled RNA in a manner consistent with a 3′-5′ exonucleolytic mechanism. Genetic and biochemical experiments indicate that Rrp6p interacts with poly(A) polymerase and with Npl3p, a poly(A)+ mRNA binding protein implicated in pre-mRNA processing and mRNA nuclear export. These findings suggest that Rrp6p may interact with the mRNA polyadenylation system and thereby play a role in a nuclear pathway for the degradation of aberrantly processed precursor mRNAs.
A comparison of aortic valve replacement via an anterior right minithoracotomy with standard sternotomy: a propensity score analysis of 492 patients

Objectives Right anterior minithoracotomy with central arterial cannulation is our preferred technique of minimally invasive aortic valve replacement (AVR). We compared perioperative outcomes with this technique to those via sternotomy. Methods Between March 1999 and December 2013, 492 patients underwent isolated AVR via either sternotomy (SAVR, n = 198) or minimally invasive right anterior thoracotomy (MIAVR, n = 294) in our institution. Univariate comparisons between groups were made to evaluate overall outcomes and adverse events. To control treatment selection bias, propensity scores were constructed from core patient characteristics. A propensity score-stratified analysis of outcome and adverse events was then performed. Results Overall mortality was 2.5 and 1.0% in the SAVR and MIAVR groups, respectively. Hospital and ICU stays were shorter, there was less intraoperative blood product usage, and fewer wound infections in the MIAVR group. There were no differences in other adverse events, including strokes. The composite end-point of alive and adverse event-free was significantly more common in the MIAVR group (83 vs 74%, P = 0.002). After adjusting for the propensity score, hospital and ICU stays remained shorter and intraoperative blood product usage remained less in the MIAVR group. There was no difference in mortality, stroke or other adverse events between groups. Conclusion Minimally invasive AVR via an anterior right thoracotomy with predominately central cannulation can be performed with morbidity and mortality similar to that of a sternotomy approach. There appear to be advantages to this minimally invasive approach when compared with sternotomy in terms of less intraoperative blood product usage, lower wound infection rates and decreased hospital stays. If mortality and the occurrence of adverse events are taken together, MIAVR may be associated with better outcomes. As minimally invasive AVR becomes more common, further long-term follow-up is needed and a prospective multicentre randomized trial would be warranted.
The mathematics of success and failure (SPC)

The use of statistical process control (SPC) to improve quality is discussed. Mathematical tools and techniques for SPC are reviewed. How to decide when a change in an indicator is statistically significant is addressed. An approach to SPC in which one attempts to reduce process sensitivity to external variations rather than control these variations more tightly is discussed. >
Training in neurology at the University of Michigan in the 1930s.

When Robert Joynt asked me to write something for theREMINISCENCESsection in theArchivesI told him that I had nothing of interest to report. He asked me again, however, and I reconsidered. Perhaps readers might have some interest in a report of my experiences as a resident in a small training program in neurology in a midsized, middle-western medical school 50 years ago. When I graduated from the University of Michigan Medical School in June 1932, Michigan had had a program in neurology for 44 years. William J. Herdman had graduated from the Department of Medicine and Surgery of the University of Michigan, then a two-year medical school, in 1875. In 1888, when he was professor of practical anatomy and demonstrator of anatomy, he was named Professor of Practical Anatomy and Diseases of the Nervous System. In 1890, his title was changed to Professor of Diseases
Regional variation in the abundance of axonal cytoskeletal proteins

The relative abundance of several axonal cytoskeletal proteins was determined by immunoassay at various sites in the peripheral and central nervous systems of adult rats. Within the peripheral nervous system, the ratio of tubulin to neurofilaments was greatest for nerves composed of unmyelinated axons and least for nerves with large myelinated axons. MAP1 protein was more prominent in unmyelinated fibers; conversely tau proteins were relatively more abundant in large myelinated axons. An immunochemical index of neurofilament phosphorylation was less for unmyelinated fibers than for myelinated ones. In the fimbria-fornix, pyramidal tract, and superior cerebellar peduncle, similar trends were observed: small axons had more MAP1, less tau, and a greater ratio of tubulin to neurofilament proteins. The phosphorylation index was greatest for the superior cerebellar peduncle, the tract with the largest axons. The immunochemical index of neurofilament phosphorylation was greater for the optic nerve than for axonal tracts in the brain proper. These results suggest that development of large myelinated axons is associated with greater neurofilament content, neurofilament phosphorylation, and with greater abundance of tau proteins in the CNS and the PNS; however, quantitative aspects of these relationships differ in the PNS and the CNS.
Outcome analysis of 9-gauge MRI-guided vacuum-assisted core needle breast biopsies

OBJECTIVE. The purpose of this article is to correlate 9-gauge MRI-guided vacuum-assisted breast biopsy with surgical histologic findings to determine the upgrade rate and to correlate the frequency of MRI-guided vacuum-assisted breast biopsy cancer diagnosis with breast MRI indications and enhancement characteristics of targeted lesions. MATERIALS AND METHODS. A database search was performed of all MRI-guided vacuum-assisted breast biopsies performed from January 1, 2005, to September 31, 2010. The breast MRI indications, history, age, risk factors, lesion size, enhancement characteristics, and pathologic diagnoses at MRI-guided vacuum-assisted breast biopsy and at surgery were documented. Fisher exact test and analysis of variance were used for statistical analysis. RESULTS. A total of 218 lesions underwent MRI-guided vacuum-assisted breast biopsy in 197 women (mean age, 52 years; range, 28–76 years), of which 85 (39%) had surgical correlation. Of the 218 lesions, 48 (22%) were malignant, 133 (61%) were...
2E RELAXATION OF CR(III) COMPLEXES IN RIGID AND FLUID MEDIA

Abstract 2E decays have been recorded for a group of Cr(III) complexes with varying 4T22E separations in solvents with independently measured relaxation times. Thermal quenching that occurs when solvent motion is slow relative to the excited state decay time leads to non-exponential decay. Comparison of the 2E lifetimes and estimated deviations from exponentiality in a wide range of complex-solvent combinations as a function of temperature suggests a model in which 2 E ⇒ 4 T 2 back-transfer is the dominant decay pathway in most complexes. The back-transfer rate is increased by solvent motion.
Production and activity of Thermomonospora curvata cellulases on protein-extracted lucerne fibers

Protein-extracted lucerne fibre (PELF) was evaluated as a carbon/energy source for cellulase production by Thermomonospora curvata and as a substrate for enzymatic conversion to soluble sugars. In shake cultures grown at 53°C, pH 8, maximal cellulase (50 endoglucanase IU and 0.7 filter paper IU/ml) was attained at a PELF concentration of 1.3% (w/v) in a vitamin-mineral salts medium buffered with 0.05 M concentrations of phosphate and N-2-hydroxyethylpiperazine-N′-2-ethanesulfonate. Multiple endoglucanase enzymes were produced. The major form had an apparent molecular weight of 22 000 and K m values of 0.23% and 0.56% for carboxymethylcellulose and PELF respectively. NaOH treatment of PELF increased its susceptibility to enzymatic hydrolysis. During enzymatic hydrolysis of NaOH-treated PELF (60°C, pH 6.1, 24h) two-thirds of total fibre carbohydrate was solubilized as cellobiose, melibiose, cellopentaose, cellotetraose, xylose and glucose in descending order of concentration.
The association of race and ethnicity with rates of drug and alcohol testing among US trauma patients

Background: Racial and ethnic minority patients often receive differential medical care compared to Caucasians. The aim of this study was to evaluate the association of race and ethnicity with rates of alcohol and drug testing among adult US trauma patients. Methods: Data for 79,246 adults admitted to 58 institutions participating in the US National Trauma Data Bank were evaluated using multivariable, hierarchical, mixed-effects analyses to determine the odds of receiving alcohol and drug testing among different racial/ethnic groups. The primary outcome variable was whether an alcohol or drug test was performed. The secondary outcome variable was the results of those tests. Participants were stratified by injury severity using the Injury Severity Score. Additional case-mix variables included: gender, age, Glasgow Coma Scale, day and time of arrival, and payment source. Results: Black and Hispanic males in all injury severity groups were tested for alcohol more frequently than Caucasian males (odds ratio for Black men 1.31, 95% confidence interval 1.16–1.47; and for Hispanic men 1.45, 95% confidence interval 1.19–1.77, in the moderate injury group). Hispanic males in the moderate injury group were also tested for drugs more frequently then Caucasian males (odds ratio 1.33, 95% confidence interval 1.09–1.63). Conclusion: Racial and ethnic minority trauma patients in the US are tested for alcohol and drugs at higher rates after adjusting for potential confounders. Because having a positive alcohol or drug test can adversely affect a patient’s medical care, differential testing that is racially or ethnically biased may place minority patients at risk of receiving disparate care.
Properties of fraction of rice hull

Abstract Hulls from waxy (IR29)and non-waxy (IR32) rice had similar compositions. The neutral sugars were mainly glucose and xylose. The major fractions were cellulose and alkali-soluble polysaccharides. Whole hull and its soluble fractions, but not the residue fraction, hardened waxy rice starch gel. Protein was mainly glutelin and was rich in proline.
White Profs at Hispanic-Serving Institutions: Radical Revolutionaries or Complicit Colonists?

This paper calls for a radical revolution in Hispanic-Serving Institutions (HSIs) grounded in the ideological conviction that racism in education is structural, oppressive to all, and distinctly harming to students, staff, and faculty of color. Deconstructing racism in the academy must be viewed as part of the institutional identity of HSIs. This work requires a coalition with those privileged and empowered by current structures and in whose name and shadow racism thrives—White people. We discuss how White professors at HSIs must join the radical revolution to fight against racism and for a cultural change outside the legalized consensus of counting Hispanics without ensuring that funding is utilized to serve them and their communities.
Clinical applications of whole-genome association studies: future applications at the bedside.

Until now, performing whole-genome association studies has been an unattainable, but highly desirable, goal for geneticists. With the recent advent of high-throughput genotyping platforms, this goal is now a reality for geneticists today and for clinicians in the not-so-distant future. This review will cover a broad range of topics to provide an overview of this emerging branch of genetics, and will provide references to more specific sources. Specifically, this review will cover the technologies available today and in the near future, the specific types of whole-genome association studies, the benefits and limitations of these studies, the applications to complex disease–gene interactions, diagnostic devices, therapeutics, and finally, we will describe the 5-year perspective and key issues.
Graduate record examinations: The test that could be your gateway to graduate school

Many graduate schools require or recommend that applicants submit scores from the Graduate Record Examinations (GREs). These tests provide a comparative measure of aptitudes and abilities considered relevant to an individual's potential for success in graduate-level study. The exams also provide a common basis for comparing the qualifications of applicants from different schools with different standards.
Whip antenna design for portable rf systems

Whip type antennas are probably the most commonly used antennas in portable rf systems, such as cordless and cellular phones, rf enabled laptop computers, personal digital assistants (PDAs), and handheld computers. Whip antennas are almost always mounted on the chassis which contains the radio and other electronics. The chassis is usually a molded plastic which is coated with a conducting paint for EMI purposes. The chassis which appears as a lossy conductor to the antenna, has several effects -- detuning, altering the gain of the antenna, and shadowing its radiation pattern. Extensive modeling and measurements must be performed in order to fully characterize the affects of the chassis on the whip antenna, and to optimize antenna type, orientation and position. In many instances, modeling plays a more important role in prediction of the performance of whip antennas, since measurements become difficult due to the presence of common mode current on feed cables. In this paper models and measurements are used to discuss the optimum choice of whip antennas and the impact of the chassis on radiation characteristics. A modeling tool which has been previously described and has been successfully used to predict radiated field patterns is used for simulations, and measured and modeled results are shown.
Indicators of maturity in apricots using biplot multivariate analysis

Apricot fruit (Prunus armeniaca L cv ‘Moorpark’) of variable ground colour were harvested from three sites. From two additional sites fruit of one colour only were harvested. Measurements were made of skin ground colour, internal levels of ethylene and carbon dioxide, total soluble solids, flesh firmness, juice viscosity, pH, total titratable acidity and flesh water content. It was found that skin ground colour was a good indicator of physiological maturity in any one site but was a poor indicator between sites. Of the measured parameters only flesh firmness, total titratable acidity and juice viscosity were found to be useful measures of physiological maturity. Due to the preoccupation of marketers and consumers with flesh firmness, it is proposed that this parameter be used each year to determine the optimal picking colour for fruit in individual orchards.
Current concepts of regulation of phosphate transport in renal proximal tubules

The wealth of new information on BBM transport of Pi which has accumulated in recent years gives an indication of the importance and intellectual challenge that the mechanism of this process poses to investigators. In this brief reflection on the field, we have tried to draw attention to some general principles and features which may be helpful as working hypotheses in the development of the field. To date, a disproportionate amount of effort may have been spent on deciphering putative intracellular regulatory mechanisms, without knowing some essential fundamental properties of the Na+-Pi-COT. We suggest that a major effort should be exerted towards elucidating biogenesis of the Na+-Pi-COT, the possible existence of a membrane cycling mechanism, and a refined analysis of the Na+-Pi-COT in specific subsegments of proximal tubules. Advances in these areas together with studies of both the rapid and long-term adaptive regulation of Pi transport are needed, given the central role of the kidney in total body Pi homeostasis both in health and disease.
Response to letter regarding article, "cardiac magnetic resonance with T2-weighted imaging improves detection of patients with acute coronary syndrome in the emergency department"

We read with interest the letter from Dr Bouzas-Mosquera about our published article.1 We appreciate both his comments and the opportunity to respond. We used a subjective assessment of the pretest probability of acute coronary syndrome (ACS) by the emergency department (ED) caregiver because it incorporates into a single metric all of the data available to decision makers before imaging. Its limitation is that it is too insensitive to use to discharge ED patients directly home without further testing for ACS. It was used because no well established, universally accepted, and validated risk score exists that can be applied to undifferentiated ED populations with chest pain. …
Activation of sea urchin spermatozoa during fertilization

Abstract Spermatozoa of sea urchins undergo a variety of activation processes, beginning at the moment of release from the male urchin and ending when fusion with the egg occurs. The biochemical mechanisms underlying these activations are now becoming clear.
The effect of diphenylhydantoin (Dilantin) sodium on atrial flutter and fibrillation provoked by focal application of aconitine or delphinine

Abstract In dogs anesthetized with Nembutal and morphine the heart was exposed, and aconitine or delphinine crystals were applied to the surface of the right atrium in order to create flutter or fibrillation. The effect of the intravenous administration of diphenylhydantoin sodium (Dilantin) on these arrhythmias was studied. In 14 experiments with aconitine and 8 with delphinine, sinus rhythm was obtained quickly, and in 20 of the 22 experiments it was obtained abruptly by the intravenous injection of 5 mg. per kilogram of diphenylhydantoin. This effect was transient, since the atrial arrhythmias reappeared within a few minutes. Repetition of the injection (up to five injections in a single experiment) had the same effect as that of the first injection. Ventricular tachycardias provoked by the topical application of aconitine crystals on the right ventricle responded in the same way as did the atrial flutter and fibrillation. Special characteristics of atrial and ventricular arrhythmias caused by diphenylhydantoin are described. The experimental and clinical literature dealing with the action of diphenylhydantoin on cardiac arrhythmias is discussed.
Social learning of food preferences by white-tailed ptarmigan chicks

The social-learning function of a food call is to share information about resources with conspecifics. Field studies on the social learning of food and parent–offspring interactions regarding food in a natural environment are rare. Our aims in a 2-year study in the Rocky Mountain National Park, U.S.A., were to monitor white-tailed ptarmigan, Lagopus leucurus , hens' food calls, a vocalizing and tidbitting display, to determine whether the hens selected foraging areas based on food availability and whether chicks learned about important food resources from hen food calls. Our findings indicate that the white-tailed ptarmigan hen's food call is a form of cultural transmission in which information regarding available food is disseminated from hens to chicks. Hens chose foraging patches where certain plant species were abundant and called their chicks to these foods, which dominated their diet. Chick consumption mirrored the calling rates of hens and as a result chicks ate high-protein foods, which are critical for chick growth and development. The results suggest that white-tailed ptarmigan hens' food calls may function to enhance survival of juvenile ptarmigan.
Ductuli efferentes of the male Golden Syrian hamster reproductive tract

Efferent ductules are responsible for the transportation of spermatozoa from the testis to the epididymis and their epithelium is responsible for the reabsorption of over 90% of the luminal fluid. The purpose of this research was to characterize the gross morphology and histology of efferent ductules in the male Golden Syrian hamster. The efferent ductules emerge from rete testis with a unique polarity at the apex or cephalic pole of the testis. The number of efferent ductules varied from 3 to 10 with an average of 6.0 and blind ending ducts were observed in approximately 56% of the males. The ductules merged into a single common duct prior to entering the caput epididymidis. The proximal efferent ductule lumen was wider than the distal (conus and common ducts), consistent with reabsorption of most of the luminal fluid, as was morphology of the ductal epithelium. Non-ciliated cells in the proximal region had prominent endocytic apparatuses, showing both coated pits and apical tubules in the apical cytoplasm. Large basolateral, intercellular spaces were also present in the epithelium of the proximal region. Distal non-ciliated cells had an abundance of large endosomes and lysosomal granules. Localisation of sodium/hydrogen exchanger-3 (NHE3; SLC9A3) and aquaporins 1 and 9 (AQP1, AQP9) along the microvillus border was also consistent with ion transport and fluid reabsorption by this epithelium. In comparison, the caput epididymidis epithelium expressed only AQP9 immunostaining. Another unusual feature of the hamster efferent ductules was the presence of glycogen aggregates in the basal cytoplasm of small groups of epithelial cells, but only in the proximal ducts near the rete testis. Androgen (AR), estrogen (ESR1 and ESR2) and vitamin D receptors (VDR) were also abundant in epithelial nuclei of proximal and distal efferent ductules. In comparison, caput epididymidis showed very little immunostaining for ESR1.
A Method for Designing Detection Monitoring Networks in Layered Aquifers with Non-uniform Flow

An integer programming method was devised to locate detection monitoring wells in layered aquifers. The method is applicable to aquifers with non-uniform groundwater flow, and it does not require that a compliance boundary be linear or perpendicular to the direction(s) of groundwater flow. In each layer, monitoring sites are defined along curvilinear transects that parallel equipotential lines. The model can be formulated to allocate wells to the transect with the highest detection efficiency, or to establish multiple lines of defense against contaminant migrating to a compliance boundary. Detection efficiencies of alternative monitoring transects are calculated from parameters obtained via numerical modeling of contaminant transport. These parameters include the narrowest plume that could traverse a monitoring transect, and the zone width of potential contaminant migration at the transect. Problem formulations are compact, and computational requirements are low relative to alternative approaches for designing detection monitoring networks in aquifers. An application to a glacial outwash aquifer demonstrates the utility of the method.
Coagulopathy secondary to vitamin K deficiency in hyperemesis gravidarum

Abstract Background: Hyperemesis gravidarum is a condition of pregnancy characterized by excessive nausea and vomiting, which can be associated with malnutrition. Vitamin K deficiency is a known complication of malnutrition as well as a known cause of coagulopathy. To date, there is no reported case in the literature of vitamin K deficiency in hyperemesis gravidarum. Case: A woman at 15 weeks’ gestation presented with hyperemesis gravidarum complicated by an episode of severe epistaxis. Investigation revealed coagulopathy secondary to vitamin K deficiency. The coagulopathy resolved after vitamin K replacement, with complete correction of all clotting factors. Conclusion: Vitamin K deficiency and coagulopathy should be considered in women with hyperemesis gravidarum who present with a bleeding diathesis. Prophylactic vitamin K replacement should be considered in cases in which hyperemesis is severe and protracted.
Evaluation of the phencyclidine-like discriminative stimulus effects of novel NMDA channel blockers in rats

Rationale Because of their potential therapeutic effects, N-methyl-d-aspartate (NMDA) receptor antagonists have been investigated for clinical use. Unfortunately, many channel-blocking antagonists have been associated with the production of side effects, including motor impairment and phencyclidine (PCP)-like subjective effects.
Renal glutathione transport: Identification of carriers, physiological functions, and controversies

Glutathione (GSH) is an endogenous tripeptide composed of the amino acids L-glutamate, L-cysteine, and glycine. It is found in virtually all aerobic cells and plays critical roles in maintenance of cellular redox homeostasis and drug metabolism. An important component of its regulation is transport across biological membranes. Because GSH is a charged, hydrophilic molecule, transport occurs via catalysis by specific carrier proteins rather than by simple diffusion. Although it has been clearly understood that efflux of GSH across membranes such as the canalicular and sinusoidal plasma membranes in hepatocytes and the brush-border plasma membrane in renal proximal tubules is a key step in GSH turnover and interorgan metabolism, the existence and physiological functions of uptake of GSH across various epithelial plasma membranes has been subject to some debate. Besides transport across plasma membranes, GSH transport across intracellular membranes, most notably the mitochondrial inner membrane, has received some attention in recent years because of the importance of mitochondrial redox status and the mitochondrial GSH pool in cellular physiology and pathology. This commentary will focus on renal transport processes for GSH and will discuss some of the controversies that have existed and still seem to exist in the literature, specifically regarding uptake of intact GSH by basolateral membranes of renal proximal tubular cells and uptake of intact GSH by the mitochondrial inner membrane.
Repeated Cocaine Self-Administration Alters Processing of Cocaine-Related Information in Rat Prefrontal Cortex

One of the core symptoms of cocaine addiction is compulsive drug-seeking behavior. Although the precise neural substrates are unknown, it has been hypothesized that this behavior involves cocaine-induced hypofunction of the prefrontal cortex (PFC) or "hypofrontality." To test this hypothesis, PFC neuronal activity was monitored in rats during approximately 3 weeks of cocaine self-administration (SA). Rats were trained to press a lever to self-administer cocaine in daily 2 h sessions. Responding was reinforced contingent on a modified fixed-ratio 5 schedule of reinforcement. In the first SA session, the overall firing rate and burst rate were significantly decreased after cocaine infusions relative to the period immediately before the session. These effects disappeared after > or = 10 d of drug SA and were replaced by a significant increase in burst duration and firing rate within a burst. Notably, however, the level of basal activity before the first drug infusion of each SA session decreased significantly after multiple weeks of cocaine exposure. Collectively, these data support the view that although repeated sessions of cocaine SA decrease basal PFC activity, increased burst-related firing in response to cocaine infusions suggests that processing of cocaine-related information is enhanced and may contribute to increased control by cocaine over cocaine-seeking behavior.
Rapid Methods and Automation in Microbiology

Introduction Rapid methods and automation in microbiology is a dynamic area in applied microbiology dealing with the study of improved methods in the isolation, early detection, characterization, and enumeration of microorganisms and their products in clinical, food, industrial, and environmental samples. In the past 15 years this field has emerged into an important subdivision of the general field of applied microbiology and is gaining momentum nationally and internationally as an area of research and application to monitor the numbers, kinds, and metabolites of microorganisms related to food spoilage, food preservation, food fermentation, food safety , and foodborne pathogens. This article traces the historical development of this field and provides information and discussions on major developments in many aspects of this rapidly changing discipline mainly from the standpoint of food microbiology and food safety. The purpose is to provide an overview of the current status of the total field and predict the developments in the near future.
Dynamics and efficiency of electron injection and transport in DNA using pyrenecarboxamide as an electron donor and 5-bromouracil as an electron acceptor

The photophysical and photochemical behavior of a series of hairpin-forming DNA conjugates possessing a 5'-tethered pyrenecarboxamide chromophore and one or two bromouracil bases has been investigated. Quenching of the pyrene fluorescence and transient absorption spectra characteristic of the pyrene cation radical are observed only when bromouracil is located at the first or second base pair position nearest to the point of pyrene attachment. These observations are consistent with an intercalated structure for these conjugates in which pyrene is adjacent to the second base pair. Selective quenching of singlet pyrene by bromouracil but not by thymine is consistent with the free energy for charge separation estimated using Weller's equation. Low quantum yields for loss of bromide when bromouracil is not adjacent to pyrene are attributed to inefficient charge separation via either a multistep electron transport or a single-step superexchange mechanism. Quantum yields are only weakly dependent upon the distance between pyrene and bromouracil, as expected for a multistep electron transport mechanism. Loss of bromide from conjugates possessing two bromouracils occurs sequentially. For adjacent bromouracils, competitive loss of bromide from both bromouracils is observed, whereas for nonadjacent bromouracils loss of bromide from the proximal bromouracil occurs prior to any loss from the distal bromouracil, consistent with a slower rate constant for electron transport vs loss of bromide.
Distribution of acetylated alpha-tubulin in brain. In situ localization and biochemical characterization.

We studied the solubility properties of brain acetylated α-tubulin, as well as the localization of this tubulin in brain tissue. Endogenous unpolymerized tubulin and cytoskeletal tubulin were fractionated after brain Triton-solubilization. Using the immunoblotting technique, we found that acetylated α-tubulin was recovered in the cytoskeletal fraction, and that most (92%) of the acetylated microtubules of this fraction were depolymerized by cold/Ca2+ treatment. In another set of experiments, axonal and soma-dendritic preparations were found to have equivalent amounts of acetylated α-tubulin. By immunogold electron microscopy, we established that acetylated microtubules are widely distributed in dendrites of the central nervous system.
Lead impairs the production of osteocalcin by rat osteosarcoma (ROS 172.8) cells

Abstract The serum level of osteocalcin, a bone-specific protein produced by osteoblasts and an index of bone formation, is decreased in lead-intoxicated children. To elucidate the effect of lead on the hormonal regulation of osteocalcin production, ROS 17 2.8 cells were treated with 0, 5, 10, or 25 μ m lead acetate for 24 hr, followed by an additional 24-hr lead treatment with or without 100 pg 1,25-dihydroxyvitamin D3/ml medium. At the end of this period a radioimmunoassay was conducted to determine the amount of osteocalcin present in the cells and secreted into the medium. 1,25-Dihydroxyvitamin D3 increased osteocalcin secretion in control cultures, but this increase was prevented by lead in a concentration-dependent manner. Osteocalcin secretion by cultures treated with 10 or 25 μ m lead was even lower than in cultures not stimulated with 1,25-dihydroxyvitamin D3. Intracellular levels of osteocalcin were slightly elevated with 1,25-dihydroxyvitamin D3, and there was no lead effect on cellular levels. These data indicate that lead attenuates basal and 1,25-dihydroxyvitamin D3-stimulated production of osteocalcin in ROS 17 2.8 cells. Because osteocalcin appears to play a central role in bone mineralization, altered osteocalcin production may be a key event in the skeletal toxicity of lead.
RECOMBINATION, RADIATIVE ENERGY LOSS, AND LEVEL POPULATIONS IN NONEQUILIBRIUM CESIUM DISCHARGES.

Abstract The transition rate equations for the populations of cesium states in a homogenous, optically thin plasma have been solved for the excited-state populations, the effective ground-state ionization and recombination coefficients, and the effective electron kinetic-energy and radiative loss coefficients. A table of values is presented for the nonequilibrium steady-state plasma which is analogous to the Saha equation for the equilibrium plasma. Free electron densities from 1012 to 1015 cm-3 are considered, and a Maxwellian electron velocity distribution at temperatures from 1500 to 3000°K is assumed. These conditions are typical of those in thermionic and magnetohydrodynamic energy converters and other cesium discharges. The rate coefficients used for collision-induced and radiative atomic transitions are described. Molecular processes, diffusion, wall losses, etc., are discussed but not included explicitly in the model. The absorption of resonance radiation is simulated by reduction of the spontaneous emission coefficients. Other radiative absorption processes are neglected. The populations are seen to depart significantly from the Boltzmann distribution in steady state, and it is seen that many excited states participate in the ionization and recombination processes. The implications of these results for spectroscopic diagnostics, volume ion production, and energy loss in a cesium-discharge plasma are discussed.
Shell Model in the Lead Region

The structure of the low-lying states in $^{206}\mathrm{Pb}$, $^{210}\mathrm{Pb}$, $^{210}\mathrm{Po}$, $^{208}\mathrm{Bi}$, $^{210}\mathrm{Bi}$, $^{208}\mathrm{Tl}$, $^{206}\mathrm{Tl}$, and $^{206}\mathrm{Hg}$ has been calculated using a conventional shell-model approach with a central Gaussian-shaped interaction plus ${P}_{2}$ and ${P}_{3}$ multipole interactions where the ${P}_{2}$ and ${P}_{3}$ strengths were varied for each nucleus. The results are compared with the experimental data and other calculations. The agreements between the experimental energies and spectroscopic factors and the calculations are in general good. The agreements between the experimental and calculated $E2$ and $M1$ rates in $^{206}\mathrm{Pb}$ and $^{210}\mathrm{Po}$ are also fairly good.
Intensifying Pacific trade winds drive regional sea level trends

Sea level in the western tropical Pacific Ocean has been increasing at a rate about 3 times the global average rate of sea level rise, as observed from satellite altimetry and tide gauges. Why are sea level trends so much different in this region? Previous studies have suggested that the high rate of sea level change in the western tropical Pacific is associated with the natural variation of the El Nino–Southern Oscillation. However, using a general circulation model, Merrifield and Maltrud show that western tropical Pacific sea level trends are likely due to a gradual intensification of the Pacific trade winds in the past 2 decades. They also highlight other aspects of ocean circulation that have been altered in response to the intensifying trade winds. Some previous research has suggested that the trade wind intensification is a result of global warming, although that has yet to be verified. If that is the case, the authors conclude, the western tropical Pacific sea level trends will likely continue to be anomalously high. (Geophysical Research Letters, doi:10.1029/2011GL049576, 2011)
Electrolyte effects in the adsorption and desorption of a cationic polyacrylamide on cellulose fibers

Adsorption isotherms for a cationic derivative polyacrylamide (QCPAM) on cellulose fibers were determined as functions of aluminum sulfate (alum) concentration and pH, and QCPAM desorption measurements in alum, NaCl, CaCl2, and LaCl3 were also made. The isotherms had a steep, but not infinite, initial slope leading to a rounded knee followed by a linear interval with a small positive slope. Polymer adsorption increased with pH due to increased dissociation of cellulose carboxyl groups. Aluminum sorption made the electrophoretic mobility of the fines less negative and lowered the capacity of the fibers to adsorb QCPAM. Exposure of QCPAM-saturated fibers to electrolyte solution resulted in polymer desorption, most of which occurred within 1 h. Most desorption in alum occurred at pH 4 with less at pH 4.5 and very little at pH 5. The molarities of LaCl3, CaCl2, and NaCl required to desorb 50% of the adsorbed QCPAM were 6.0 × 10−4, 2.1 × 10−3, and 8.3 × 10−3 M, respectively.
Production of crystallizable fragments of membrane proteins.

Many membrane proteins feature autonomously folded extramembranous domains which, when isolated from the intact protein, perform biochemical functions relevant to biological activity. Whereas intact membrane proteins usually require detergent solubilization for purification, most extramembranous fragments are soluble in aqueous solution. If appropriately constructed, such fragments are often crystallizable and the resulting atomic structures can lead to important biological insight. In most instances, these fragments are produced in recombinant expression systems. To be crystallizable, molecular fragments should be uniform in composition and conformation and be available in abundance. Considerations for the production of crystallizable fragments of membrane proteins include the definition of fragment boundaries, the control of nonuniformities introduced by glycosylation or phosphorylation, and optimization of expression systems. These aspects are addressed here in general terms and in the case studies of applications to CD4, CD8, the insulin receptor kinase, and N-cadherin.
Thresholds and reversibility in brittle cracks: An atomistic surface force model

A new picture of environmentally-enhanced fracture in highly brittle solids is presented. It is asserted that the fundamental relations for crack growth are uniquely expressible in terms of the surface force functions that govern the interactions between separating walls in an intrusive medium. These functions are the same, in principle, as those measured directly in the newest submolecular-precision microbalance devices. A fracture mechanics model, based on a modification of the Barenblatt cohesive zone concept, provides the necessary framework for formalizing this link between crack relations and surface force functions. The essence of the modification is the incorporation of an element of discreteness into the surface force function, to allow for geometrical constraints associated with the accommodation of intruding molecules at the crack walls. The model accounts naturally for the existence of zero-velocity thresholds; further, it explains observed shifts in these thresholds in cyclic load-unload-reload experiments, specifically the reduction in applied loading needed to propagate cracks through healed as compared to virgin interfaces. The threshold configurations emerge as thermodynamic equilibrium states, definable in terms of interfacial surface energies. Crack velocity data for cyclic loading in mica, fused silica and sapphire are presented in support of the model. Detailed considerations of the theoretical crack profiles in these three materials, with particular attention to the atomic structure of the “lattice” (elastic sphere approximation) at the interfaces, shows that intruding molecules must encounter significant diffusion barriers as they penetrate toward the tip region. It is concluded that such diffusion barriers control the fracture kinetics at low driving forces. At threshold the barriers become so large that the molecules can no longer penetrate to the tip region. This leads to a crucial prediction of our thesis, that the cohesive zone consists of two distinct parts: a “protected” primary zone adjacent to the tip, where intrinsic binding forces operate without influence from environmental influences; and a “reactive” secondary zone more remote from the tip, where extrinsic interactions with intruding chemical species are confined. The prevailing view of chemically enhanced brittle fracture, that crack velocity relations are determined by a concerted reaction with reactive species at a single line of crack-tip bonds, is seen as a limiting case of our model, operative at driving forces well above the threshold level. The new description offers the potential for using brittle fracture as a tool for investigating surface forces themselves.
Mutations in the right operator of bacteriophage lambda: Evidence for operator-promoter interpenetration

Abstract A set of virulent mutants of bacteriophage lambda have been selected from λv2 v3. The sites of mutation form two microclusters, both close to v3. Some of the mutants, selected for their ability to grow on a λ-lysogen, can also grow on a λdv carrier strain. They are called “supervirulent” and a mutation conferring super-virulence is called vs. The sites of mutation to vs lie between the presumed promoter mutants (x3, x7) and x13, implying that the operator and promoter interpenetrate each other. The relative affinities of λ repressor for binding, in vitro, to λv+, λv3, λvs326, and λv3 vs327 DNA were 1, 1 4 , 1 20 , and 1 4000 , respectively. We suggest that two separate mutations in the right operator are needed to confer virulence because promoter sites lie within the operator.