cssi/SciSciGPT-SciSciNet huggingface dataset:
Role of the mitochondria in immune-mediated apoptotic death of the human pancreatic β cell line βLox5.

Mitochondria are indispensable in the life and death of many types of eukaryotic cells. In pancreatic beta cells, mitochondria play an essential role in the secretion of insulin, a hormone that regulates blood glucose levels. Unregulated blood glucose is a hallmark symptom of diabetes. The onset of Type 1 diabetes is preceded by autoimmune-mediated destruction of beta cells. However, the exact role of mitochondria has not been assessed in beta cell death. In this study, we examine the role of mitochondria in both Fas- and proinflammatory cytokine-mediated destruction of the human beta cell line, βLox5. IFNγ primed βLox5 cells for apoptosis by elevating cell surface Fas. Consequently, βLox5 cells were killed by caspase-dependent apoptosis by agonistic activation of Fas, but only after priming with IFNγ. This beta cell line undergoes both apoptotic and necrotic cell death after incubation with the combination of the proinflammatory cytokines IFNγ and TNFα. Additionally, both caspase-dependent and -independent mechanisms that require proper mitochondrial function are involved. Mitochondrial contributions to βLox5 cell death were analyzed using mitochondrial DNA (mtDNA) depleted βLox5 cells, or βLox5 ρ0 cells. βLox5 ρ0 cells are not sensitive to IFNγ and TNFα killing, indicating a direct role for the mitochondria in cytokine-induced cell death of the parental cell line. However, βLox5 ρ0 cells are susceptible to Fas killing, implicating caspase-dependent extrinsic apoptotic death is the mechanism by which these human beta cells die after Fas ligation. These data support the hypothesis that immune mediators kill βLox5 cells by both mitochondrial-dependent intrinsic and caspase-dependent extrinsic pathways.
The molecular genetics of the incision step in the DNA excision repair process.

This review describes the evolution of research into the genetic basis of how different organisms use the process of excision repair to recognize and remove lesions from their cellular DNA. One particular aspect of excision repair, DNA incision, and how it is controlled at the genetic level in bacteriophage, bacteria, S. cerevisae, D. melanogaster, rodent cells and humans is examined. In phage T4, DNA is incised by a DNA glycosylase-AP endonuclease that is coded for by the denV gene. In E. coli, the products of three genes, uvrA, uvrB and uvrC, are required to form the UVRABC excinuclease that cleaves DNA and releases a fragment 12-13 nucleotides long containing the site of damage. In S. cerevisiae, genes complementing five mutants of the RAD3 epistasis group, rad1, rad2, rad3, rad4 and rad10 have been cloned and analyzed. Rodent cells sensitive to a variety of mutagenic agents and deficient in excision repair are being used in molecular studies to identify and clone human repair genes (e.g. ERCC1) capable of complementing mammalian repair defects. Most studies of the human system, however, have been done with cells isolated from patients suffering from the repair defective, cancer-prone disorder, xeroderma pigmentosum, and these cells are now beginning to be characterized at the molecular level. Studies such as these that provide a greater understanding of the genetic basis of DNA repair should also offer new insights into other cellular processes, including genetic recombination, differentiation, mutagenesis, carcinogenesis and aging.
ILR1, an amidohydrolase that releases active indole-3-acetic acid from conjugates

In plants, the growth regulator indole-3-acetic acid (IAA) is found both free and conjugated to a variety of amino acids, peptides, and carbohydrates. IAA conjugated to leucine has effects in Arabidopsis thaliana similar to those of free IAA. The ilr1 mutant is insensitive to exogenous IAA-Leu and was used to positionally clone the Arabidopsis ILR1 gene. ILR1 encodes a 48-kilodalton protein that cleaves IAA-amino acid conjugates in vitro and is homologous to bacterial amidohydrolase enzymes. DNA sequences similar to that of ILR1 are found in other plant species.
Role of myocardial hypoxia in the remodeling of the embryonic avian cardiac outflow tract.

Abstract The embryonic cardiac outflow myocardium originates from a secondary heart-forming field to connect the developing ventricles with the aortic sac. The outflow tract (OFT) subsequently undergoes complex remodeling in the transition of the embryo to a dual circulation. In avians, elimination of OFT cardiomyocytes by apoptosis (stages 25–32) precedes coronary vasculogenesis and is necessary for the shortening of the OFT and the posterior rotation of the aorta. We hypothesized that regional myocardial hypoxia triggers OFT remodeling. We used immunohistochemical detection of the nitroimidazole EF5, administered by intravascular infusion in ovo, as an indicator of relative tissue oxygen concentrations. EF5 binding was increased in the OFT myocardium relative to other myocardium during these stages (25–32) of OFT remodeling. The intensity of EF5 binding paralleled the prevalence of apoptosis in the OFT myocardium, which are first detected at stage 25, maximal at stage 30, and diminished by stage 32. Evidence of coincident hypoxia-dependent responses included the expression of the vascular endothelial growth factor (VEGF) receptor 2 by the OFT myocardium, the predominant expression of VEGF122 (diffusible) isoform in the OFT, and the recruitment of QH1-positive pro-endothelial cells to the OFT and vasculogenesis. Exposure of embryos to hyperoxia (95% O 2 /5% CO 2 ) during this developmental window reduced the prevalence of cardiomyocyte apoptosis and attenuated the shortening and rotation of the OFT, resulting in double-outlet right ventricle morphology, similar to that observed when apoptosis is directly inhibited. These results suggest that regional myocardial hypoxia triggers cardiomyocyte apoptosis and remodeling of the OFT in the transition to a dual circulation, and that VEGF autocrine/paracrine signaling may regulate these processes.
An Infant Ventilator Technique for Resistive Unloading during Spontaneous Breathing. Results in a Rabbit Model of Airway Obstruction

ABSTRACT: The combined system of ventilator circuit, endotracheal tube, and lung commonly imposes a resistive load on spontaneous breathing efforts. It is possible to compensate for this positive resistance by a device generating a “negative ventilator resistance” (NVR), i.e. delivering a positive pressure during inspiration and a negative pressure during expiration in constant proportion to the instantaneous flow of the spontaneous breathing. The concept of NVR implies that there must not be any phase lag between flow and pressure signals. In eight anesthetized, intubated, spontaneously breathing rabbits (mean body wt 3570 g, range 2900-4600 g), challenged either by aerosolized histamine or an extrapulmonary resistive load, lung mechanical data were calculated from esophageal pressure and flow signals. Each animal served as its own control with and without NVR. In a total of 39 experiments, NVR was applied in amounts between 1 and 15 kPa.s/L. During both types of additional resistive load, NVR immediately reduced the resistive work of breathing. There was a strong linear correlation between the amount of NVR applied and the decrease in total resistance, where the total resistance equals the resistive load on the animal's respiratory muscles (sum of the resistances of all components of the combined respirator-lung system): r = 0.93, p < 0.001. The relationship between NVR and the drop in resistive work per mL of tidal volume was similar: r = 0.85, p < 0.001. Throughout the experiments, NVR operated in perfect synchronization with the animal's spontaneous breathing activity.
Planar magnetoresistivity and planar hall effect measurements in nickel single-crystal thin films☆☆☆

Abstract The planar magnetoresistivity anisotropy and the planar Hall effect in nickel single-crystal films have been explained successfully by using a phenomenological equation in a tensor form. The anisotropy constants defined for this equation are directly related to the planar measurements and can be used as parameters for making relative comparisons in the study of the magnetoresistivity anisotropy effects. It is demonstrated that these effects in ferromagnetic crystals can be studied by measurements on single-crystal films.
Unlocking the molecular secrets of sodium-coupled transporters

Transmembrane sodium-ion gradients provide energy that can be harnessed by 'secondary transporters' to drive the translocation of solute molecules into a cell. Decades of study have shown that such sodium-coupled transporters are involved in many physiological processes, making them targets for the treatment of numerous diseases. Within the past year, crystal structures of several sodium-coupled transporters from different families have been reported, showing a remarkable structural conservation between functionally unrelated transporters. These atomic-resolution structures are revealing the mechanism of the sodium-coupled transport of solutes across cellular membranes.
DIABETIC CATARACTS AND FLAVONOIDS

Oral administration of quercitrin, an inhibitor of aldose reductase, leads to a significant decrease in the accumulation of sorbitol in the lens of diabetic Octodon degus. The onset of cataract is effectively delayed when quercitrin is continuously administered. Thus in these diabetic animals, as in galactosemic rats, the use of an effective aldose reductase inhibitor impedes the course of cataract development. These observations support the hypothesis that in diabetes, as in galactosemia, aldose reductase plays a key role in initiating the formation of lens opacity.
Spectral principal components of the upwelling light field from the ocean surface

A method is provided for the decoupling of the upwelling light field from the bottom reflectance component. A principal components analysis of the remaining water volume backscatter component is performed. A method is suggested for a decoupling procedure for use in remote sensing over specific locales.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Transanal endoscopic surgery using a single access port: a practical tool in the surgeon's toybox.

Large polyps and early carcinomas of the rectum may be excised with transanal endoscopic surgery (TES). Single-port techniques are emerging in the field of colorectal surgery and have been adapted to many colorectal procedures so far. In this article, we aimed to present our initial experience with TES using a single access port with its technical details. Patients undergoing TES using a single access port between July 2010 and January 2013 were included in the study. Patient demographics, operative technique, and both operative and postoperative outcomes were evaluated and presented. A total of 12 patients (ten males) were included in our study. The median age was 63.5 years (50–84), median American Society of Anesthesiologists (ASA) score was 3 (2–4), and median body mass index was 28.8 kg/m2 (17.4–55.6). Median operating time was 79 min (43–261). Histopathological diagnoses were as follows: tubulovillous adenoma (n = 6), tubular adenoma (n = 4), adenocarcinoma (n = 1), and neuroendocrine tumor (n = 1). Five patients were sent home on the day of surgery and the median postoperative hospital stay was 1 day (0–38). Median estimated blood loss was 22.5 ml (5–150). A transient urinary retention was developed in one patient postoperatively, and two patients had postoperative bleeding. The first of these patients with a long history of anticoagulant usage had rectal bleeding 13 days after surgery, which was successfully managed with medical treatment. The second patient was morbidly obese, had multiple comorbidities, and had rectal bleeding on postoperative day 7 which was managed with local epinephrine injection. He suffered unrelated cardiac death on postoperative day 38. TES is safe and feasible when using a single port and in the standard laparoscopic setting. The single-port technique may play a major role in the widespread utilization of TES as a treatment for large adenomas and early rectal cancers.
The Context of Satisficing in Vignette Research

Abstract Social psychologists use vignette experiments to study cognitive aspects of social interaction. The quality of data produced in vignette research can be enhanced by minimizing the tendency of subjects to satisfice in formulating their responses, that is, to cognitively process vignette information in a careless and ineffective way. This article draws from research on the cognitive aspects of survey measurement to clarify conditions likely to encourage satisficing and reports vignette experimental data obtained in a sample of American college students that demonstrate predicted context effects on satisficing.
Transoceanic Transmission of 40 $\,\times\,$ 117.6 Gb/s PDM-OFDM-16QAM Over Hybrid Large-Core/Ultralow-Loss Fiber

We experimentally demonstrated transmitting 40 × 117.6 Gb/s 16 quadrature amplitude modulation with orthogonal frequency division multiplexing modulation over 10 181 km. The following techniques are applied to achieve error-free transmission: 1) hybrid large-core/ultralow-loss fibers were used for improving received optical signal-to-noise ratio while enhancing fiber nonlinearity tolerance; 2) multiband nonlinearity compensation algorithm was performed to further improve nonlinearity tolerance; 3) the forward error correction (FEC) limit of 5.3 dB provided by the concatenation of hard-decision and soft-decision FEC codes ensures to have error-free transmission after turbo equalizer with memory of three symbols, thus attaining a spectral efficiency of 4.7 b/s/Hz.
Scale Model Studies of Station Grounding Grids

The design and use of scale models for evaluating the performance of grounding grids is described. Construction details of two electrolytic tanks of different sizes and of a number of scale- model grids are discussed, together with the associated instrumentation. Results are presented showing the potential profiles for a number of grids and the effects of the number of meshes, the use of ground rods, and non-uniform soil resistivity.
CHANGES IN SHUNT AND DEADSPACE IN A TRIPARTITE LUNG MODEL DURING NITRIC OXIDE INHALATION. † 278

CHANGES IN SHUNT AND DEADSPACE IN A TRIPARTITE LUNG MODEL DURING NITRIC OXIDE INHALATION. † 278
Prolonged use of intraluminal arterial shunts without systemic anticoagulation.

Abstract Background: Temporary arterial shunts maintain perfusion while surgeons postpone arterial repairs. The common indications are combined orthopedic and vascular injuries and damage control. The duration of patency and the need for systemic anticoagulation remain in question. We examined our experience for answers. Methods: We searched for patients who had temporary arterial shunts and collected the following: mechanism, artery injured, shunt time, blood loss and transfusions, injury severity score (ISS,) mangled extremity severity score (MESS,) and anticoagulation. Results: Of 19 patients, 10 had shunts for damage control (group 1,) and 9, for orthopedic/vascular injuries (group 2.) group 1 had significantly higher shunt time, mortality, ISS, and MESS. Shunt time ranged from 47 to 3,130 minutes (52 hours.) Two patients, 1 in each group, required amputations. Conclusions: Temporary arterial shunts can be use for combined orthopedic and vascular injuries and for damage control. Shunts can stay open for 52 hours without systemic anticoagulation.
The yellow zone in asthma treatment: is it a gray zone?

Objectives To review the available literature on methods of preventing and minimizing exacerbations and to target problems for improvement. Data Sources PubMed and Cochrane Review searches of the English-language literature using the following key yellow zone terms: asthma exacerbation, self-management plans, inhaled corticosteroids, and acute management of asthma exacerbations. Study Selection Articles relevant to our yellow zone intervention inquiry. Results The National Institutes of Health (NIH) guidelines advocate that physicians give patients written action plans with instructions on managing home (yellow zone) exacerbations. However, the criteria used to identify the yellow zone are ambiguous and often confusing to patients and physicians. In addition, apart from a passing mention that doubling doses of inhaled corticosteroids may be an option in asthma step-up care, the guidelines contain no recommendations for yellow zone treatment strategies. This deficiency is directly related to the paucity of organized evidence on the efficacy of the various pharmacological interventions that can be used during an exacerbation. Conclusions Translating the NIH guidelines into realistic clinical practice requires a clearer and more patient-friendly definition of the yellow zone, and this improved definition will facilitate the prescription of effective interventions in the management of yellow zone exacerbations.
The New Economics Of Innovation, Spillovers And Agglomeration: Areview Of Empirical Studies

This paper reviews recent empirical studies of location and innovation. The objective is to highlight the questions addressed, approaches adopted, and further issues that remain. The review is organized around the traditions of measuring geographically mediated spillovers and productivity studies that introduce a geographic dimension. The first part identilies four separate strains in thc empirical spillover literature: innovation production functions; the linkages between patent citations. defined as paper trails: the rnobility of skilled labor based on the notion that knowledge spillovers are transmitted through people; and, last, knowledge spillovers embodied in traded goods. The second part considers the composition of agglomeration economies, the attributes of knowlcdge, and the characteristics of firms.
A Survey of Extended-Interval Aminoglycoside Dosing Practices in United States Adult Cystic Fibrosis Programs

INTRODUCTION: The Cystic Fibrosis Foundation recently deemed the use of extended-interval dosing (EID) of aminoglycosides acceptable for the treatment of cystic fibrosis (CF) pulmonary exacerbations. However, current practice across United States adult CF programs and affiliate programs is unknown. The objectives of this research are to characterize the practice trends, dosing strategies, therapeutic drug-monitoring practices, and adverse effect monitoring of the EID of aminoglycosides in the treatment of pulmonary exacerbations across United States adult CF programs. METHODS: A 34-question online survey instrument was distributed on behalf of the author by the United States Cystic Fibrosis Foundation to all United States adult CF programs and affiliate programs. RESULTS: Of the 68 participating adult CF programs (44.4% survey response rate), 64 (94.1%) reported using EID of aminoglycosides (as once-daily or twice-daily dosing). More than 95% of programs reported frequently or always using this dosing method. Tobramycin dosed 10 mg/kg/d every 24 h, infused over 30–60 min, was the most commonly cited regimen. Monitoring of aminoglycoside serum concentrations was reported by all programs, with a tobramycin peak of 25–30 mg/L and trough of < 1 mg/L targeted most frequently. Nephrotoxicity was commonly monitored through serum creatinine measurements, while ototoxicity was monitored by audiometry in approximately one-half of programs. CONCLUSIONS: This study indicates that the use of EID of aminoglycosides across United States adult CF programs has increased considerably since the publication of the CF pulmonary exacerbation guidelines and now appears to be the most common method for dosing aminoglycosides in adults with CF.
Assessment of Collaboration in U.S. Health Care Delivery: A Perspective from Systems Theory

This analysis applies the core principles of systems theory to health care delivery in the United States. Particularly examined is the role of collaboration between health care agencies/organizations in the United States. This includes cooperation and teamwork among health professionals (i.e., nurses, technicians, physicians, and laboratory staff). By and large, systems theory posits that (a) all singular units within a system are interconnected and (b) the whole is more than the sum of its parts. This analysis identifies areas within the U.S. public health system where it is essential to embody elements of cooperation and collaboration, not only to bolster physical and financial support, but also to ensure a substantial impact within the community.
Skin Melanization in the Domestic Turkey Meleagris gallopavo

Abstract SKIN coloration from bluish-black pigment, melanin, has been observed recently as a major problem in many turkey flocks in the United States and Canada. The coloration, while obvious in live turkeys, is more pronounced following processing at sub-scald water temperature. There is considerable variation in the pigment intensity and dispersion over the skin surface. The objectionable coloration has resulted in down-grading of dressed turkeys. In referring to skin pigmentation in turkeys it is necessary to distinguish between the so-called “blue-back” and dermal melanosis. Blue-back is the result of melanin spreading in skin tissue from damaged immature feathers of colored varieties of turkeys. The blue-back areas are usually the tail, hips, back, neck and tops of wings where damage from feather picking or treading occurs. Skin tissue over the keel may also show damage as a result of irritation from roosting. Dermal melanosis is characterized by melanin deposition in skin tissue…
Computer modeling ofα‐ toβ′‐ form phase transitions using theoretical triglyceride structures

Intermolecular energy calculations were performed on theoretical triarachidinα-form structures as selected bond rotations converted them intoβ′-forms with a chain-tilt change in the glycerol region. Interactions across the methyl gaps amounted to only 2-3% of the total energy in initialα- and finalβ′-forms, but computer generated energy profiles duringα- toβ′-phase transitions revealed highly repulsive regions due to the close approach of methyl groups. This methyl gap interaction, plus additional repulsive interactions in the lateral packing of molecules during rigid chain rotations, necessitated modification of certain chain movements during phase transition to reduce excessive repulsive energy. These results suggest that phase transitions proceed in a particular sequence of events that either distribute energy to promote further phase excitation or that lead to collapse into the stable polymorphic form. Phase transition energy curves also reveal that secondaryα- andβ′-forms are possible and are dependent on the startingα-forms, the direction of chain rotation and the subcell arrangement.
Brain Docosahexaenoate Accretion in Fetal Baboons: Bioequivalence of Dietary α-Linolenic and Docosahexaenoic Acids

The dietary bioequivalence during the brain growth spurt ofα-linolenic (LNA) and docosahexaenoic acids (DHA) as substrates for brain and retinal n-3 fatty acid accretion is reported for the fetal baboons, whose mothers consumed a long chain polyunsaturate-free diet with an-6/n-3 ratio of 10:1. Pregnant baboons received i.v. doses of U-13C-labeled fatty acids (LNA or DHA), plasma was collected from mother and fetus, and fetal brain (occipital cortex), retina, and liver were analyzed at various times post-dose. Fetal brain DHA plateaued 15-35 d post-dose with 1.6% of the preformed [U-13C-]DHA dose recovered in the brain. In contrast, LNA-derived DHA accretion also plateaued but was 20-fold lower. Liver and retinal results were of the same order of magnitude, but showed evidence of peaks and decline. Conversion products to n-3 long chain polyunsaturate were observed in the maternal circulation at 1 h after administration, as was transfer of both fatty acids to the fetus. From these measurements we estimate that a dietary level of about 0.45% of energy as LNA is sufficient to meet the requirements of the growing fetal brain, whereas 0.03% of energy as DHA would suffice. These data are the first direct measurements of the bioequivalence of DHA and LNA in developing primates and imply that n-3 fatty acid requirements for the developing fetal brain can be met by attainable dietary LNA for diets low in long chain polyunsaturates.
The future terrorists in America

Looks at the self‐reported perceptions of police chiefs in a majority of US cities with a population exceeding 100,000. Identifies, regionally and nationally, those internal domestic groups that have the greatest potential for terrorism within the next two years. Finds that anti‐abortionists were predicted to be the most likely group to attack at national level, but that when predictions were sought for geographical areas, each respondent believed that there was a greater likelihood of terrorism in Washington DC or New York City than in their own area. Finds that there had been no significant increase in planning against terrorism.
The space groups of point group C3: some corrections, some comments.

A survey of the October 2001 release of the Cambridge Structural Database [Cambridge Structural Database (1992). Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge, England] has uncovered approximately 675 separate apparently reliable entries under space groups P3, P3_1, P3_2 and R3; in approximately 100 of these entries, the space-group assignment appears to be incorrect. Other features of these space groups are also discussed.
Low-frequency oscillations in arterial pressure and heart rate: a simple computer model

We have previously reported that low-frequency oscillations in arterial blood pressure (ABP) and heart rate (HR) occur when conscious dogs experience severe blood loss. These low-frequency oscillations are generated by enhancement of the sympathetic nervous system and inhibition of the parasympathetic nervous system. We have developed a simple computer model to elucidate those properties critical to the generation of these oscillations. Our model incorporates several important features: 1) arterial baroreceptor feedback loops, which relate ABP to targeted HR and total peripheral resistance (TPR) values; 2) two effector outputs, HR and TPR, which are controlled by the outputs of vagal, beta-adrenergic, and alpha-adrenergic effector mechanisms; 3) a fixed beat-to-beat stroke volume; and 4) a wind-kessel model, which represents the peripheral circulation. Each effector mechanism is modeled as a low-pass filter in series with a delay. The vagal effector mechanism slows the HR after a 100-ms delay and reaches maximal HR at that time. The beta-adrenergic effector mechanism speeds HR after a 2.5-s delay and then increases to maximal HR 7.5 s later. The alpha-adrenergic effector mechanism begins vasoconstriction after a 5-s delay and then reaches maximal contraction 15 s later. Computer simulations of inhibition of the vagal effector mechanism and activation of the adrenergic effector mechanisms elicit low-frequency oscillations in ABP and HR. These oscillations are similar to those observed experimentally in the dog during hemorrhage. We conclude that the slow temporal response of the alpha-adrenergic effector mechanism controlling TPR is the critical element in predicting the observed low-frequency oscillations in ABP and HR.
Nanomechanics of polymer gels and biological tissues: A critical review of analytical approaches in the Hertzian regime and beyond

We survey recent progress in the application of nanoindentation to characterize the local mechanical properties of polymer gels and biological tissues. We review the theories, analytical models based thereon, and data processing techniques commonly used to determine elastic properties of these classes of materials by instrumented nanoindentation. Examples from the testing of synthetic and biological gels are used to illustrate the limitations of existing theories and approaches. Emphasis is placed on the need for contact mechanics models that more accurately represent the large-strain behaviour of soft matter.
Acrylamide Inhibits Dopamine Uptake in Rat Striatal Synaptic Vesicles

Evidence suggests that acrylamide (ACR) neurotoxicity is mediated by decreased presynaptic neurotransmitter release. Defective release might involve disruption of neurotransmitter storage, and therefore, we determined the effects of in vivo and in vitro ACR exposure on 3H-dopamine (DA) transport into rat striatal synaptic vesicles. Results showed that vesicular DA uptake was decreased significantly in rats intoxicated at either 50 mg/kg/day x 5 days or 21 mg/kg/day x 21 days. ACR intoxication also was accompanied by a reduction in KCl-evoked synaptosomal DA release, although consistent changes in presynaptic membrane transport were not observed. Silver stain and immunoblot analyses suggested that reduced vesicular uptake was not due to active nerve terminal degeneration or to a reduction in the synaptic vesicle content of isolated striatal synaptosomes. Nor did the in vivo presynaptic effects of ACR involve changes in synaptosomal glutathione concentrations. In vitro exposure of striatal vesicles showed that both ACR and two sulfhydryl reagents, N-ethylmaleimide (NEM) and iodoacetic acid (IAA), produced concentration-dependent decreases in 3H-DA uptake. Although ACR was significantly less potent than either NEM or IAA, all three chemicals caused comparable maximal inhibitions of vesicular uptake. Kinetic analysis of DA uptake showed that in vitro exposure to either ACR or NEM decreased V(max) and increased K(m). Determination of radiolabel efflux from 3H-DA-loaded vesicles indicated that in vitro ACR did not affect neurotransmitter retention. These data suggest that ACR impaired neurotransmitter uptake into striatal synaptic vesicles, possibly by interacting with sulfhydryl groups on functionally relevant proteins. The resulting disruption of neurotransmitter storage might mediate defective presynaptic release.
Advantages of cooperation between reinforcement learning agents in difficult stochastic problems

Presents the first results in understanding the reasons for cooperative advantage between reinforcement learning agents. We consider a cooperation method which consists of using and updating a common policy. We tested this method on a complex fuzzy reinforcement learning problem and found that cooperation brings larger than expected benefits. More precisely, we found that K cooperative agents each learning for N time steps outperform K independent agents each learning in a separate world for K*N time steps. We explain the observed phenomenon and determine the necessary conditions for its presence in a wide class of reinforcement learning problems.
Laboratory evaluation of desert soils for irrigation

A simple laboratory technique of evaluating desert soils for suitability to irrigation is outlined. Such laboratory observations are for the purpose of augmenting a field examination of physiographic and pedological limitations of the land. The method is based upon the premise that soil moisture retained against a tension of 100-cm water tension, less the moisture retained against 15,000-cm tension, gives an index of total available water in the soil. The importance of the relative distribution of available moisture within the tension range of 100 and 15,000 cm is indicated.
Nature and the Natural

As part of my interest in the persistence of unproductive debates about the relative importance of nature and nurture, I focus here on the especially problematic relation between nature and the natural. For if the definition of nature is problematic, its semantic relation to ‘natural’ is even more so. I explore some of the problems that arise from slippage between substantive and normative conceptions of ‘natural’ (inviting collateral slippage between is and ought), from the bifurcatory structure of its negation and from changing assumptions about nature's domain.
Stochastic integral equation solver for efficient variation-aware interconnect extraction

In this paper we present an efficient algorithm for extracting the complete statistical distribution of the input impedance of interconnect structures in the presence of a large number of random geometrical variations. The main contribution in this paper is the development of a new algorithm, which combines both Neumann expansion and Hermite expansion, to accurately and efficiently solve stochastic linear system of equations. The second contribution is a new theorem to efficiently obtain the coefficients of the Hermite expansion while computing only low order integrals. We establish the accuracy of the proposed algorithm by solving stochastic linear systems resulting from the discretization of the stochastic volume integral equation and comparing our results to those obtained from other techniques available in the literature, such as Monte Carlo and stochastic finite element analysis. We further prove the computational efficiency of our algorithm by solving large problems that are not solvable using the current state of the art.
Early phonological and lexical development and otitis media: a diary study

This diary study describes early phonological and lexical development in a child with chronic otitis media with effusion. Equipped with the tools of a referential/analytic language-learner, the child solved the problem of reduced and fluctuating auditory input with phonological selection and avoidance strategies that capitalized on prosodic cues. This «tone-language» approach resulted in a lexical inventory that would be categorized as an extreme expressive style. Having «boot-strapped» her lexical learning, the child continued to rely on phonological constraints and selection strategies to fuel lexical and syntactic growth, i.e. cross-domain interactions leading to a vocabulary spurt and the onset of two-word utterances
Genetic mouse models to study blood–brain barrier development and function

The blood–brain barrier (BBB) is a complex physiological structure formed by the blood vessels of the central nervous system (CNS) that tightly regulates the movement of substances between the blood and the neural tissue. Recently, the generation and analysis of different genetic mouse models has allowed for greater understanding of BBB development, how the barrier is regulated during health, and its response to disease. Here we discuss: 1) Genetic mouse models that have been used to study the BBB, 2) Available mouse genetic tools that can aid in the study of the BBB, and 3) Potential tools that if generated could greatly aid in our understanding of the BBB.
Chemical probes and tandem mass spectrometry: a strategy for the quantitative analysis of proteomes and subproteomes

Quantitative proteome profiling using mass spectrometry and stable isotope dilution is being widely applied for the functional analysis of biological systems and for the detection of clinical, diagnostic or prognostic marker proteins. Because of the enormous complexity of proteomes, their comprehensive analysis is unlikely to be routinely achieved in the near future. However, in recent years, significant progress has been achieved focusing quantitative proteomic analyses on specific protein classes or subproteomes that are rich in biologically or clinically important information. Such projects typically combine the use of chemical probes that are specific for a targeted group of proteins and may contain stable isotope signatures for accurate quantification with automated tandem mass spectrometry and bioinformatics tools for data analysis. In this review, we summarize technical and conceptual advances in quantitative subproteome profiling based on tandem mass spectrometry and chemical probes.
Emerging Issues in the Cross-Cultural Study of Empathy

Especially since the discovery of mirror neurons, scholars in a variety of disciplines have made empathy a central focus of research. Yet despite this recent flurry of interest and activity, the cross-cultural study of empathy in context, as part of ongoing, naturally occurring behavior, remains in its infancy. In the present article, I review some of this recent work on the ethnography of empathy. I focus especially on the new issues and questions about empathy that the ethnographic approach raises and the implication of these for the study of empathy more generally.
The Potassium Channel Kir4.1 Associates with the Dystrophin-Glycoprotein Complex via α-Syntrophin in Glia

One of the major physiological roles of potassium channels in glial cells is to promote "potassium spatial buffering" in the central nervous system, a process necessary to maintain an optimal potassium concentration in the extracellular environment. This process requires the precise distribution of potassium channels accumulated at high density in discrete subdomains of glial cell membranes. To obtain a better understanding of how glial cells selectively target potassium channels to discrete membrane subdomains, we addressed the question of whether the glial inwardly rectifying potassium channel Kir4.1 associates with the dystrophin-glycoprotein complex (DGC). Immunoprecipitation experiments revealed that Kir4.1 is associated with the DGC in mouse brain and cultured cortical astrocytes. In vitro immunoprecipitation and pull-down assays demonstrated that Kir4.1 can bind directly to alpha-syntrophin, requiring the presence of the last three amino acids of the channel (SNV), a consensus PDZ domain-binding motif. Furthermore, Kir4.1 failed to associate with the DGC in brains from alpha-syntrophin knockout mice. These results suggest that Kir4.1 is localized in glial cells by its association with the DGC through a PDZ domain-mediated interaction with alpha-syntrophin and suggest an important role for the DGC in central nervous system physiology.
Investigation of the nature of the methionine-π interaction in β-hairpin peptide model systems

There are frequent contacts between aromatic rings and sulfur atoms in proteins. However, it is unclear to what degree this putative interaction is stabilizing and what the nature of the interaction is. We have investigated the aryl-sulfur interaction by placing a methionine residue diagonal to an aromatic ring on the same face of a beta-hairpin, which places the methionine side chain in close proximity to the aryl side chain. The methionine (Met)-aryl interaction was compared with an equivalent hydrophobic and cation-pi interaction in the context of the beta-hairpin. The interaction between phenylalanine (Phe), tryptophan (Trp), or cyclohexylalanine (Cha) and Met stabilized the beta-hairpin by -0.3 to -0.5 kcal mole(-1), as determined by double-mutant cycles. The peptides were subjected to thermal denaturations that suggest a hydrophobic driving force for the interactions between Met and Trp or Cha. The observed interaction of Met or norleucine (Nle) with Trp or Cha are quite similar, implying a hydrophobic driving force for the Met-pi interaction. However, the thermodynamic data suggest that there may be some differences between the interaction of Met with Trp and Phe and that there may be a small thermodynamic component to the Met...Phe interaction.
Nitric Oxide-20–Hydroxyeicosatetraenoic Acid Interaction in the Regulation of K+ Channel Activity and Vascular Tone in Renal Arterioles

Abstract—The present study examined whether inhibition of P4504A enzyme activity and the formation of 20-HETE contributes to the activation of K+ channels and vasodilator effects of nitric oxide (NO) in renal arterioles. Addition of an NO donor to the P4504A2 enzyme that produces 20-HETE increased visible light absorbance at 440 nm indicating that NO binds to heme in this enzyme. NO donors also dose-dependently inhibited the formation of 20-HETE in microsomes prepared from renal arterioles. In patch-clamp experiments, NO donors increased the open-state probability of a voltage-sensitive, large-conductance (195±9 pS) K+ channel recorded with cell-attached patches on renal arteriolar smooth muscle cells. Blockade of guanylyl cyclase with [1H-[1,2,4]Oxadiazolo[4,3-a] quinoxalin-1-one] (ODQ, 10 μmol/L), or cGMP-dependent kinase with 8R,9S,11S-(−)-9-methoxycarbamyl-8-methyl-2,3,9,10-tetrahydro-8,11-epoxy-1H,8H,11H-2,7b,11a-trizadibenzo-(a,g)-cy-cloocta-(c,d,e)-trinden-1-one (KT-5823) (1 μmol/L) did not alter t...
Cactus Alkaloids X: Isolation of Hordenine and N-Methyltyramine from Ariocarpus kotschoubeyanus

Hordenine HCl and N-methyltyramine HCl were crystallized from extracts of the cactus Ariocarpus kotschoubeyanus (Lemaire) Schumann. Other alkaloids, which have been found in closely related Ariocarpus species, were not detected in this species. Extraction of the isolated alkaloids by percolation gave higher yields than continuous extraction.
The Continuous Locking Suture Technique

The continuous locking suture technique is described for use in endodontic surgery. The technique is an effective way to close Ochsenbein-Luebke flaps. The importance of the assistant's role is described. The technique's advantages and disadvantages are discussed.
Cell-Specific Regulation of the c-myc Gene by Lymphocyte Mitogens and Platelet-Derived Growth Factor

We show that c-myc is an inducible gene that is regulated by specific growth signals in a cell-cycle-dependent manner. Specifically, agents that initiate the first phase of a proliferative response in lymphocytes (lipopolysaccharide or Concanavalin A) and fibroblasts (platelet-derived growth factor) induce c-myc mRNA. Within one to three hr after the addition of these mitogens to the appropriate cells, c-myc mRNA concentration is increased between 10- and 40-fold. This induction of c-myc mRNA occurs in the presence of cycloheximide and, therefore, does not require the synthesis of new protein species. Consequently, the induction of c-myc mRNA is not secondary to growth. In addition, c-myc mRNA is "superinduced" by the combination of cycloheximide and mitogen, a finding consistent with a model that a labile protein may regulate c-myc levels in these cells. Further, this work suggests a regulatory linkage between the function of two oncogenes--c-myc and c-sis--the latter being the putative structural gene for PDGF.
The variation of βR with probe in inelastic hadron scattering and the adequacy of first-order calculations☆

Abstract The predicted probe dependence of the collective parameter δ = βR, obtained from distorted wave analyses of inelastic scattering data, is shown to have been observed for a variety of hadrons from low to intermediate energies for 0+ → 2+ transitions in single-closed-shell nuclei. These results, when compared to electromagnetic data, show an internal consistency which provides both a check of the validity of the first-order reaction mechanism as well as a determination of the relative neutron to proton transition matrix elements to ≈15% accuracy. The empically determined systematically variation of neutron and proton transition strenghts are in agreement with a schematic calculation of core polarization.
The Biology of Prostaglandins and Related Eicosanoids in Invertebrates: Cellular, Organismal and Ecological Actions'

SYNOPSIS. Prostaglandins and related eicosanoids are oxygenated metabolites of C20 polyunsaturated fatty acids. These compounds have been detected in species representing all major animal phyla. The significance of eicosanoids lies in two broad areas of animal biology. In one, eicosanoids are involved in regulation of many cellular events. In the other, eicosanoids facilitate certain ecological interactions. Eicosanoids are known best in the narrow context of their clinical signif-icance in human medicine. In this essay we suggest a new, broader paradigm for understanding the meaning of eicosanoids. Under this paradigm, called the biological paradigm, we note eicosanoids were recruited into roles as biological signal moieties long before the origins of the Metazoa. During the ensuing evolutionary diversification of animals, eicosanoids have been used in a vast diversity of biolog ical roles, some of which occur only in invertebrates. We think this diversity endows eicosanoids with unusual explanatory power in apprehending biological phenomena. In this review, we recount the literature on eicosanoids in protozoans and procaryotes, then provide a detailed review of the roles of eicosanoids in inverte-brate immunity. We draw upon recent work in parasitoiogy to outline an ecological role of eicosanoids in host-parasite relationships. It appears to us that eicosanoids exert profound effects at the cellular, organismal and ecological levels ofbiological organization. We suggest that continued inquiry into the biological significance of eicosanoids will yield important new information on invertebrates.
Human chorionic gonadotropin β-subunit-like immunoreactive material in the plasma of women wearing an intrauterine progesterone contraceptive system

A systematic study of the presence of human chorionic gonadotropin beta-subunit--like (hCG beta-like) material in the plasma of one woman sampled daily throughout one menstrual cycle and in nine women studied on a selected bleeding schedule has been carried out. Peaks of immunoreactive hCG beta-like activity were found in the follicular and luteal phases of these menstrual cycles which could not be explained by a cross-reaction of luteinizing hormone (LH) in the plasma. The same nine women were studied again 1 month after the insertion of the intrauterine progesterone contraceptive system (IPCS) and again 6 to 8 months later. Although the presence of hCG beta-like immunoactivity correlated with LH values in the cycles studied, there was a significant decrease in its presence 1 month after IPCS use and a highly significant decrease after 6 to 8 months of use.
Reactions on the surface and inside of neutron stars

Measurements from orbiting X-ray satellites during the last decades have provided us with a wealth of information about nuclear reactions thought to occur in the extreme, highdensity environment of neutron stars. With radioactive ion beams from first-generation facilities we have begun to study some of these processes in the laboratory. In this contribution I report on experiments performed with radioactive beams from the ATLAS accelerator at Argonne. I will discuss the nuclear physics of X-ray bursts and super-bursts, the production of in-flight radioactive beams, as well as novel detectors which are used in these experiments.
Sediment Accumulation in Prairie Wetlands under a Changing Climate: the Relative Roles of Landscape and Precipitation

Sediment accumulation threatens the viability and hydrologic functioning of many naturally formed depressional wetlands across the interior regions of North America. These wetlands provide many ecosystem services and vital habitats for diverse plant and animal communities. Climate change may further impact sediment accumulation rates in the context of current land use patterns. We estimated sediment accretion in wetlands within a region renowned for its large populations of breeding waterfowl and migrant shorebirds and examined the relative roles of precipitation and land use context in the sedimentation process. We modeled rates of sediment accumulation from 1971 through 2100 using the Revised Universal Soil Loss Equation (RUSLE) with a sediment delivery ratio and the Unit Stream Power Erosion Deposition model (USPED). These models predicted that by 2100, 21–33 % of wetlands filled completely with sediment and 27–46 % filled by half with sediments; estimates are consistent with measured sediment accumulation rates in the region reported by empirical studies. Sediment accumulation rates were strongly influenced by size of the catchment, greater coverage of tilled landscape within the catchment, and steeper slopes. Conservation efforts that incorporate the relative risk of infilling of wetlands with sediments, thus emphasizing areas of high topographic relief and large watersheds, may benefit wetland-dependent biota.