cssi/SciSciGPT-SciSciNet huggingface dataset:
Pituitary Adenylate Cyclase-activating Peptide (PACAP) Recruits Low Voltage-activated T-type Calcium Influx under Acute Sympathetic Stimulation in Mouse Adrenal Chromaffin Cells

Low voltage-activated T-type Cav3.2 calcium channels are expressed in neurosecretory chromaffin cells of the adrenal medulla. Previous studies have shown that naive adrenal chromaffin cells express a nominal Cav3.2-dependent conductance. However, Cav3.2 conductance is up-regulated following chronic hypoxia or long term exposure to cAMP analogs. Thus, although a link between chronic stressors and up-regulation of Cav3.2 exists, there are no reports testing the specific role of Cav3.2 channels in the acute sympathoadrenal stress response. In this study, we examined the effects of acute sympathetic stress on T-type Cav3.2 calcium influx in mouse chromaffin cells in situ. Pituitary adenylate cyclase-activating peptide (PACAP) is an excitatory neuroactive peptide transmitter released by the splanchnic nerve under elevated sympathetic activity to stimulate the adrenal medulla. PACAP stimulation did not evoke action potential firing in chromaffin cells but did cause a persistent subthreshold membrane depolarization that resulted in an immediate and robust Ca2+-dependent catecholamine secretion. Moreover, PACAP-evoked secretion was sensitive to block by nickel chloride and was acutely inhibited by protein kinase C blockers. We utilized perforated patch electrophysiological recordings conducted in adrenal tissue slices to investigate the mechanism of PACAP-evoked calcium entry. We provide evidence that stimulation with exogenous PACAP and native neuronal stress stimulation both lead to a protein kinase C-mediated phosphodependent recruitment of a T-type Cav3.2 Ca2+ influx. This in turn evokes catecholamine release during the acute sympathetic stress response.
The Effect of Surface Finishing on the Tribological Behavior of a 94% Alumina Ceramic Material

The effect of surface finish on the unlubricated sliding wear behavior of a 94% A1 2 O 3 ceramic material has been investigated using a reciprocatingright cylinder-on-flat tribometer. The surface finishes evaluated were produced using a combinationof SiC and diamond abrasive particles. Profilometry was employed to characterize surface topography and x-ray diffraction was used to determine the residual stress associated with each finishing process. The coefficients of friction and controlling wear mechanisms varied dramatically as the maximum asperity height was altered by different finishing techniques. Below a peak profile of 0.25 μm, the coefficient of friction varied between 0.60 and 0.75 due to preferential shearing of the siliceous binder phase which segregated at surfacial pores and grain boundaries. Binder adhesion in the sliding contact produced stick-slip frictional behavior. Surfaces with asperity heights in excess of 10 μin exhibited intergranularfracture or grain “pluck-out”. These surfaces contained minimal real areas of contact and yielded friction coefficients of 0.30 - 0.35. Removed alumina grains actedas hard abrasives in the contact zone and enhanced transgranular fracture by a lateral cracking mechanism. Evidence of crack propagation as a result of Mode II and Mode III shearloading was discovered at subsurface pore sites. The influences of microindentation hardness and fracture toughness are discussed in terms of their relative importances on the observed wear behavior.
Effect size and practical importance: a non‐monotonic match

As an alternative to statistical testing, effect size has a non‐monotonic linkage with practical importance. Besides random variance and systematic bias, a proper interpretation of effect size hinges on its implication to outcomes of deductive and/or inductive enquiries. Consequently, a small effect size might suggest an important finding, and the same effect size could represent results of different importance. The research community could miss important findings if large effect size values are always expected for professional publication.
The Role of Snapping in Alpheus Heterochaelis Say, 1818, the Big-Clawed Snapping Shrimp

[Die Funktion des Knallens der Knallgarnele Alpheus heterochaelis wurde in Abhangigkeit von den Bedingungen Geschlecht, Grosenunterschied, Tag und Nacht, an Tieren untersucht, die jeweils zu zweit in das Versuchsgefas gesetzt wurden. Grosere Tiere haben bessere Aussichten, Auseinander-setzungen zu gewinnen; Sieger knallen haufiger; nachts hat das Tier, das mit dem Knallen beginnt, grosere Aussichten zu gewinnen. Am Tage herrschen visuelle Verhaltensauserungen vor, nachtsuber akustische. Es wird vermutet, das die Entstehung der visuellen Verhaltensauserungen dadurch begunstigt wird, da sie energiesparender sind., Die Funktion des Knallens der Knallgarnele Alpheus heterochaelis wurde in Abhangigkeit von den Bedingungen Geschlecht, Grosenunterschied, Tag und Nacht, an Tieren untersucht, die jeweils zu zweit in das Versuchsgefas gesetzt wurden. Grosere Tiere haben bessere Aussichten, Auseinander-setzungen zu gewinnen; Sieger knallen haufiger; nachts hat das Tier, das mit dem Knallen beginnt, grosere Aussichten zu gewinnen. Am Tage herrschen visuelle Verhaltensauserungen vor, nachtsuber akustische. Es wird vermutet, das die Entstehung der visuellen Verhaltensauserungen dadurch begunstigt wird, da sie energiesparender sind.]
Exploiting Users' Inconsistent Preferences in Online Social Networks to Discover Private Friendship Links

In a social network system, a friendship relation between two users is usually represented by an undirected link and it is visible in both users' friend lists. Such a dual visibility of a friendship link may raise privacy threats. This is because both the users of a friendship link can separately control its visibility to other users and their preferences of sharing such a friendship link may not be consistent. Even if one of them conceals the friendship link from a third user, that third user may find the link through the other user's friend list. In addition, as most social network users allow their friends to see their friend lists, an adversary can exploit these inconsistent policies caused by users' conflicting preferences to identify and infer many of a targeted user's friends and even reconstruct the topology of an entire social network. In this paper, we propose, characterize and evaluate such an attack referred as the Friendship Identification and Inference (FII) attack. In an FII attack scenario, an adversary first accumulates the initial attack relevant information based on the friend lists visible to him in a social network. Then, he utilizes this information to identify and infer a target's friends using a random walk based approach. We formally define the attack and present the attack steps, the attack algorithm and various attack schemes. Our experimental results using three real social network datasets show that FII attacks are effective in inferring private friendship links of a target and predicting the topology of the social network. Currently, most popular social network systems, such as Facebook, LinkedIn and Foursquare, are susceptible to FII attacks.
Bilinear Behavior in Nano and Microindentation Tests of fcc Polycrystalline Materials

α-brass and aluminum microhardness and deep nanoindentation data when fitted to the Taylor dislocation-hardening (TDH) model produced a straight-line behavior consistent with the model. Literature data, including copper silver and tungsten when also fitted to TDH model, exhibited results similar to the ones produced by the α-brass and aluminum data. The nanohardness data obtained at shallower depths also exhibited straight-line behavior but with a shallower slope. Taken together the nano-microindentation data constituted what we term a bilinear behavior, and we shall discuss possible mechanisms for this behavior.
Near Real-Time Retroflexion Detection in Colonoscopy

Colonoscopy is the most popular screening tool for colorectal cancer. Recent studies reported that retroflexion during colonoscopy helped to detect more polyps. Retroflexion is an endoscope maneuver that enables visualization of internal mucosa along the shaft of the endoscope, enabling visualization of the mucosa area that is difficult to see with typical forward viewing. This paper describes our new method that detects retroflexion during colonoscopy. We propose region shape and location (RSL) features and edgeless edge cross-section profile (ECSP) features that encapsulate important properties of endoscope appearance and edge information during retroflexion. Our experimental results on 50 colonoscopy test videos show that a simple ensemble classifier using both ECSP and RSL features can effectively identify retroflexion in terms of analysis time and detection rate.
The Understanding of Emotional and Social Attributions in Deaf Adolescents

The present study examined deaf adolescents’ understanding of causes and emotions using an attributional model. Subjects consisted of 137profoundly deaf high school students (mean age = 17.2 years) who were tested in Simultaneous Communication for their understanding of causal concepts, emotion concepts, and perceived cause‐affect associations. No significant differences were found for age and only one significant difference was found for sex. However, all of the comparisons involving language achievement level were highly significant, with the higher deaf students consistently scoring better than the lower subjects. Data obtained from a former study of 188 hearing children from two developmental levels (mean ages = 6.4, 10.4 years) were included for purposes of comparison. The deaf students evidenced a similar affective understanding to that of the younger (first‐grade) level. The results indicate that language plays an important role in the understanding of causal ascriptions, emotion concepts, and caus...
The structure, composition and elastic properties of the teleost bulbus arteriosus in the carp, Cyprinus carpio

Abstract 1. 1. Pressure-volume studies show that the bulbus arteriosus of carp (Cyprinus carpio) is extremely distensible and resilient. 2. 2. Studies with specific elastic tissue stains, fluorescence and elastase show that the bulbus has abundant elastic tissue. 3. 3. Bulbar elastic tissue differs from that of mammalian aorta in its coloration by non-specific stains, lack of lamellar distribution and marked solubility in hot 0·1 N NaOH and warm 89% formic acid. 4. 4. Smooth muscle cells in the bulbus probably synthesize its elastic tissue.
A comparison of a lecture and computer program to teach fundamentals of the Draw-a-Person test.

Background Although computer-assisted education has been used to augment education in many areas, there are few studies of programs designed to replace lectures in a medical curriculum. Objective To test whether a thoughtfully designed computer program can replace a standard lecture in a pediatrics curriculum while teaching the subject matter equally well. Methods A computer program was developed to teach the Draw-a-Person developmental test using the multimedia-authoring tool Director. One of us (A.E.C.) tested and modified the program several times during its creation after submitting it to several objective evaluators. Thirty-nine students taking the clinical pediatrics rotation were chosen by month to interact with the program or attend the lecture. All students then scored 3 drawings and assigned them a developmental age according to the Draw-a-Person test rules. Students assigned to the computer program also completed a questionnaire evaluating the program in several subjective areas. A t test for 2 samples assuming equal variance was used to analyze the test results. Results Students receiving the lecture (control group) scored the 3 drawings as 5.43 years (age range, 4.5-8 years), 9.08 years (age range, 7-12 years), and 3.5 years (age range, 2-5 years), respectively. Those using the computer program (study group) scored the 3 drawings as 5.91 years (age range, 5-7 years), 7.68 years (age range, 7-8 years), and 4.34 years (age range, 3-5 years), respectively. The correct answers for the ages were 6, 7.75, and 4.25 years, respectively. A t test for 2 samples assuming equal variance showed that students using the computer program performed better on all 3 drawings ( P P P Conclusions Students using the computer program were more accurate than students attending the lecture when scoring drawings and estimating a developmental age from them. These results support the conclusion that a thoughtfully designed computer program can replace a standard lecture in a pediatrics curriculum.
On subsequences of the Haar system inC(Δ)

Spaces arising as spans of subsequences of the Haar system inC(Δ) are studied. It is shown that for any compact metric spaceH there is a subsequence whose span is isomorphic toC(H), yet that subsequences exist whose spans are not ℒ∞ spaces.
Targeting TopBP1 at a convergent point of multiple oncogenic pathways for cancer therapy

The progression of many solid tumours is driven by deregulation of multiple common pathways, particularly Rb, PI(3)K/Akt and p53. Prior studies identified TopBP1 as a key mediator for the oncogenic gain-of-function activities of mutant p53 (mutp53) in cancer. In Akt-hyperactive cancer, TopBP1 forms oligomers and represses E2F1-dependent apoptosis. Here we perform a molecular docking screening and identify a lead compound, calcein, capable of blocking TopBP1 oligomerization and p53 binding, resulting in re-activation of E2F1-dependent apoptosis and blockade of mutp53 gain-of-function. Calcein AM, the cell-permeable derivative of calcein, shows significant antitumour activity in a wide spectrum of cultured cancer cells harbouring high TopBP1 levels. These biochemical findings are recapitulated in breast cancer xenograft models. Thus, our study provides proof-of-concept evidence for targeting TopBP1, a convergent point of multiple pathways, as a cancer therapy.
Formal parsing systems

Automatic syntactic analysis has recently become important for both natural language data processing and syntax-directed compilers. A formal parsing system G = (V, m, T, R) consists of two finite disjoint vocabularies, V and T, a many-many map, m, from V onto T, and a recursive set R of strings in T called syntactic sentence classes. Every program for automatic syntactic analysis determines a formal parsing system.A directed production analyzer (I, T, X, r) is a nondeterministic pushdown-store machine with internal vocabulary I, input vocabulary T, and all productions of r in the form: (Z, a) → aY1 ··· Ym, Z, Yi e I, a e T. Every context-free language can be analyzed by a directed production analyzer.
Practical interference alignment and cancellation for MIMO underlay cognitive radio networks with multiple secondary users

In the underlay cognitive radio approach, secondary users (SUs) are allowed to transmit their messages as long as the negative impact on the performance of the primary user (PU) is below a certain threshold. We consider a MIMO underlay cognitive radio network with a single PU and multiple SUs. We propose a practical interference alignment and cancellation scheme that not only avoids interference at the PU, but also optimizes SUs' performance in terms of degrees of freedom. Given any SU, the interference from the other SUs is aligned, and the interference at the SU from the PU is cancelled in the spatial domain. We give the feasibility condition for achieving interference alignment and cancellation. Due to the NP-hardness of the problem, we resort to approximation algorithms. We also consider practical issues for implementation. The effectiveness of the proposed scheme is shown by simulation results.
The object-ownership model: a case study for inheritance and operator overloading

Any comprehensive course on object-oriented programming must cover the topics of inheritance and overloading. In addition, in view of the relatively large size of some objects, one should also cover the efficiency of parameter passing techniques. By using recent research results, we motivate and present an effective case study that thoroughly examines the concepts and subtleties of each of these topics.
Dynamin 1 regulates amyloid generation through modulation of BACE-1.

Background: Several lines of investigation support the notion that endocytosis is crucial for Alzheimer’s disease (AD) pathogenesis. Substantial evidence have already been reported regarding the mechanisms underlying amyloid precursor protein (APP) traffic, but the regulation of beta-site APP-Cleaving Enzyme 1 (BACE-1) distribution among endosomes, TGN and plasma membrane remains unclear. Dynamin, an important adaptor protein that controls sorting of many molecules, has recently been associated with AD but its functions remain controversial. Here we studied possible roles for dynamin 1 (dyn1) in Ab biogenesis. Principal Findings: We found that genetic perturbation of dyn1 reduces both secreted and intracellular Ab levels in cell culture. There is a dramatic reduction in BACE-1 cleavage products of APP (sAPPb and bCTF). Moreover, dyn1 knockdown (KD) leads to BACE-1 redistribution from the Golgi-TGN/endosome to the cell surface. There is an increase in the amount of surface holoAPP upon dyn1 KD, with resultant elevation of a–secretase cleavage products sAPPa and aCTF. But no changes are seen in the amount of nicastrin (NCT) or PS1 N-terminal fragment (NTF) at cell surface with dyn1 KD. Furthermore, treatment with a selective dynamin inhibitor Dynasore leads to similar reduction in bCTF and Ab levels, comparable to changes with BACE inhibitor treatment. But combined inhibition of BACE-1 and dyn1 does not lead to further reduction in Ab, suggesting that the Ab-lowering effects of dynamin inhibition are mainly mediated through regulation of BACE-1 internalization. Ab levels in dyn1 2/2 primary neurons, as well as in 3-month old dyn1 haploinsufficient animals with AD transgenic background are consistently reduced when compared to their wildtype counterparts. Conclusions: In summary, these data suggest a previously unknown mechanism by which dyn1 affects amyloid generation through regulation of BACE-1 subcellular localization and therefore its enzymatic activities.
A prospective evaluation of fibrosis progression in patients with recurrent hepatitis C virus following liver transplantation

Recurrence of hepatitis C virus (HCV) following liver transplantation (LT) is universal. A subset of these patients develop advanced fibrosis and cirrhosis and it is believed that this leads to increased posttransplantation mortality. The specific aims of this study were to determine the incidence of advanced fibrosis and those factors associated with this process, and to evaluate causes for mortality in patients with recurrent HCV. A total of 227 patients who underwent LT with chronic HCV were monitored prospectively. The mean age of this group at LT was 49.5 yr; 76% were male and 85% were Caucasian. Fibrosis progression was monitored by protocol liver biopsy, initially performed 6 months after LT and then at 6- to 24-month intervals. Advanced fibrosis, defined as the bridging fibrosis or cirrhosis, developed in 1%, 11%, 25%, and 41% of patients after 1, 3, 5, and 6-10 yr, respectively. Acute cellular rejection hepatic steatosis, a persistent elevation in serum alanine aminotransferase and donor-race were associated with the development of advanced fibrosis. In contrast, the development of advanced fibrosis was not affected by the use of interferon prior to undergoing LT, cytomegalovirus disease, or donor age. A total of 60 patients (26%) died over 15 yr of follow-up. Although graft failure accounted for 45% of deaths in patients with advanced fibrosis, this represented only 8% of all deaths in patients with recurrent HCV. Sepsis was the most common cause of death and this was observed with similar frequency in patients who developed advanced fibrosis (45%) and in those with less advanced fibrosis (47%). In conclusion, approximately 41% of patients with recurrent HCV developed advanced fibrosis 6-10 yr after LT. However, complications associated with sepsis, not recurrent cirrhosis, was the most common cause of death in patients with recurrent HCV and this was similar in patients with or without advanced fibrosis.
The METAL English-to-German system: First progress report

METAL est un systeme de traduction automatique qui fait l'objet de recherches au centre de recherches linguistiques de l'universite du Texas, a Austin, depuis le debut des annees 70. Les recherches se sont internationalisees et ce systeme de traduction de l'anglais vers l'allemand comprend 77 regles de grammaire et un registre lexical de 14944 formes canoniques dans les deux langues. Le fonctionnement de METAL EG est presente dans cet article
DNA damage by anthracycline drugs in human leukemia cells

Abstract Leukemia cells from 4 acute myelocytic leukemia (AML) and 1 acute lymphocytic leukemia (ALL) patients were incubated with a set of 6 anthracycline agents: Adriamycin (Am), 4′-epi-Adriamycin (4′-epi-Am), daunorubicin (Dm), 4-demethyoxy-daunorubicin (4-dDm), carminomycin (Cm) and N-trifluoroacetyl-Am-14-valerate (AD32). Cells were assayed for drug uptake after incubation for 2 h, and for DNA damage and drug retention 4 h later. Uptake and retention patterns were characteristic for each agent and fairly uniform for the different cell populations. In contrast, profiles of the amount of DNA damage produced reflected striking differences in each population of cells. These individual responses raise the possibility that leukemic cells resistant to one anthracycline may yet be sensitive to another.
An observational study of the effectiveness of practice guideline implementation strategies examined according to physicians' cognitive styles

Reviews of guideline implementation recommend matching strategies to the specific setting, but provide little specific guidance about how to do so. We hypothesized that the highest level of guideline-concordant care would be achieved where implementation strategies fit well with physicians' cognitive styles. We conducted an observational study of the implementation of guidelines for hypertension management among patients with diabetes at 43 Veterans' Health Administration medical center primary care clinics. Clinic leaders provided information about all implementation strategies employed at their sites. Guidelines implementation strategies were classified as education, motivation/incentive, or barrier reduction using a pre-specified system. Physician's cognitive styles were measured on three scales: evidence vs. experience as the basis of knowledge, sensitivity to pragmatic concerns, and conformity to local practices. Doctors' decisions were designated guideline-concordant if the patient's blood pressure was within goal range, or if the blood pressure was out of range and a dose change or medication change was initiated, or if the patient was already using medications from three classes. The final sample included 163 physicians and 1,174 patients. All of the participating sites used one or more educational approaches to implement the guidelines. Over 90% of the sites also provided group or individual feedback on physician performance on the guidelines, and over 75% implemented some type of reminder system. A minority of sites used monetary incentives, penalties, or barrier reduction. The only type of intervention that was associated with increased guideline-concordant care in a logistic model was barrier reduction (p < 0.02). The interaction between physicians' conformity scale scores and the effect of barrier reduction was significant (p < 0.05); physicians ranking lower on the conformity scale responded more to barrier reduction. Guidelines implementation strategies that were designed to reduce physician time pressure and task complexity were the only ones that improved performance. Education may have been necessary but was clearly not sufficient, and more was not better. Incentives had no discernible effect. Measurable physician characteristics strongly affected response to implementation strategies.
Historical perspectives of The American Association for Thoracic Surgery: Herbert C. Maier (1908-1993).

Herbert Caill e Maier, 46th president of The American Association for Thoracic Surgery, was born on March 24, 1908, the son of Otto and Dina Maier. Dr Otto Maier was a successful generalist in Manhattan, and both he and Dina had emigrated from Germany at the end of the 19th century. They started their family late in life; their daughter Dorothea was born in 1906, when both parents were 41, and Herbert was born a year later. At the age of 12, Herbert had diabetes insipidus, which was a poorly understood disease in 1920. His case was so severe that he was forced to take a 5-month leave of absence from Trinity school in New York City. Maier’s initial polydipsia and polyuria gradually resolved, and he was able to go back to school, with his only symptom being occasional headaches. Eventually, he matriculated as an undergraduate at Columbia University, where he received his AB in 1928. After graduation, he enrolled in medical school at Columbia University. He graduated in 1932 and stayed on as a resident in surgery. In 1938, Maier’s headaches became more frequent and severe, at times affecting his ability to perform as a resident surgeon.Maier described his symptoms as ‘‘a pounding pulsation concomitant with each heartbeat which developed in the head and upper neck after climbing a flight or two of stairs.’’ When these episodes occurred, he was nearly incapacitated by the pain. Skull radiographs revealed bone destruction of the dorsum sellae and a tumor mass of the left maxillary sinus. After radiation therapy for presumed craniopharyngioma, his symptoms resolved; however, the radiation therapy was not without consequence. Maier described the development of impaired immunity, manifested by frequent infections, and pituitary deficiency requiring lifelong cortisone and thyroid replacement therapy. With his symptoms controlled,Maier was able to return to his clinical activities. After completion of his surgical training and a period of postdoctoral study at the University of Michigan (where he received the designation ‘‘MedScD,’’ a distinction he included in all his correspondence), he became an instructor and eventually Clinical Professor of
Reproductive and economic impact following controlled introduction of cattle persistently infected with bovine viral diarrhea virus into a naive group of heifers

The reproductive impact following controlled introduction of animals persistently infected (PI) with bovine viral diarrhea virus (BVDV) was evaluated in BVDV-naive heifers. Heifers were randomly allocated into two groups: an unexposed control herd (n = 34) and a herd exposed to five persistently infected (PI) animals for 7 mo, beginning 50 days before the breeding season (n = 34). Initiation of the BVDV-challenge was timed to mimic either direct contact with PI calves born in the previous calving season or accidental introduction of PI herd additions prior to the breeding season. The PI animals represented BVDV Types 1a (n = 3), 1b (n = 1) and 2 (n = 1). Two BVDV-free, seropositive bulls were used in each group for 78 days breeding seasons. In both groups, 33 of 34 heifers became pregnant, with similar distribution of fetal ages. Two heifers in each group aborted (etiology undetermined). In addition, one calf was born dead and one calf died 3 days post-partum in the BVDV-exposed group. One calf in the unexposed group died 4 mo post-partum. No calves, including the stillborn calf and the two calves that died prior to weaning, were persistently infected with BVDV. In summary, introduction of PI cattle to a group of BVDV-naive heifers 50 days prior to the breeding season did not negatively impact reproductive performance. To the contrary, the active immunity that developed following field exposure to BVDV provided effective reproductive and fetal protection during the breeding season and subsequent gestations, despite continuous exposure to PI animals until approximately midgestation. Although BVDV can have potentially devastating reproductive effects, timing of infection is a critical determinant in the outcome of a BVDV infection. A controlled breeding season with introduction of herd additions at less critical reproductive time points can mitigate the negative reproductive health consequences of BVDV.
Milk protein production in cows abomasally infused with casein or glucose.

Abstract Lactating Holstein cows fed above standard allowances for energy and protein were abomasally infused with casein or glucose in four trials to study effects on milk protein production and related responses. Infusion periods were 5 to 7 days long, preceded and followed by a control period. Milk protein yields were increased by abomasal infusion of casein in three of four trials. Erratic intakes of feed masked treatment effects in one trial, but casein infusion still raised protein percent in milk. Higher milk yields and increased protein in milk both contributed to responses of milk protein. Isocaloric infusion of glucose or glucose plus casein raised protein production above controls but not as much as casein alone. Responses to casein infusion were similar when rations contained 14 or 38% of total nitrogen as nonprotein nitrogen. Nonprotein nitrogen in milk generally increased with protein infusion but represented only a minor part of the nitrogen increase in milk. Multiple regression analyses indicated that response to protein infusion depended more on milk yield than on amount infused. These studies demonstrate a specific response to abomasally infused protein in well-fed cows.
Induction of nonspecific, proliferative dependent suppressor T lymphocytes in human mixed lymphocyte cultures.

Abstract Previous studies in animals and man have supported the role of suppressor cells in the control of the humoral and cellular immune response to soluble antigens. In the present studies we characterized the induction of suppressor cells in human mixed lymphocyte culture (MLC) and the effect of these cells on proliferation in MLC. Purified (monocyte-free) responder (Ac) and mitomycin-treated allogeneic lymphocytes (Bx) were used to establish standard 6-day one-way MLC (AcBx). Cells were harvested from this MLC and were then tested for suppressor activity in a second MLC containing stimulator and responder lymphocytes (ABx) autologous to cells in the first MLC. Suppressor cells were generated in MLC (AcBx) which inhibited proliferation when added on Day 1 of the second MLC (ABx); 1.6 × 103 suppressor cells (AcBx) induced 50% suppression when cultured with 105 stimulator and 105 responder cells. Further studies demonstrated that (a) suppressor cells were T lymphocytes, (b) induction and manifestation of suppressor activity was dependent on proliferation, and (c) suppressor activity was not absolutely restricted by HLA-D compatibility of suppressor and responder cells nor by antigenic specificities. These data support the possibility that in man in the allogeneic immune response is controlled by the development of suppressor T cells. The nonspecific character of the suppressor cells generated in MLC suggest that the induction of suppressors in vivo by antigen(s) may under certain circumstances reduce generalized immune responsiveness.
SAR prescreener enhancement through multi-look processing

The Army Research Laboratory (ARL) has recently examined single-polarity, synthetic aperture radar (SAR) data collected in spotlight mode at X band as part of an effort to identify land mines in radar imagery. This data set consists of several single-polarization, extremely high-resolution, spotlight-mode SAR images from multiple passes over a common target area that includes various reference reflectors as well as the landmines. In earlier investigations at Ku band, we observed that a multi-look averaging scheme could enhance the contrast between mines and background clutter. In the most recent investigation, we hypothesize that a similar behavior would be present in the X band imagery, and we demonstrate how the enhanced contrast from multi-look processing leads to improved prescreener performance under certain conditions. Results are presented in the form of receiver operating characteristic (ROC) curves for different several different prescreener parameter settings.
Hydrous melting of the martian mantle produced both depleted and enriched shergottites

The search for water in our solar system is one of the primary driving forces for planetary science and exploration because water plays an important role in many geologic processes and is required for biologic processes as we currently understand them. Excluding Earth, Mars is the most promising destination in the inner solar system to find water, as it is undoubtedly responsible for shaping many geomorphologic features observed on the present-day martian surface; however, the water content of the martian interior is currently unresolved. Much of our information about the martian interior comes from studies of the basaltic martian meteorites (shergottites). In this study we examined the water contents of magmatic apatites from a geochemically enriched shergottite (the Shergotty meteorite) and a geochemically depleted shergottite (the Queen Alexandria Range 94201 meteorite). From these data, we determined that there was little difference in water contents between the geochemically depleted and enriched shergottite magmas. The water contents of the apatite imply that shergottite parent magmas contained 730–2870 ppm H 2 O prior to degassing. Furthermore, the martian mantle contains 73–290 ppm H 2 O and underwent hydrous melting as recently as 327 Ma. In the absence of plate tectonics, the presence of water in the interior of Mars requires planetary differentiation under hydrous conditions. This is the first evidence of significant hydrogen storage in a planetary interior at the time of core formation, and this process could support elevated H abundances in the interiors of other terrestrial bodies like the Moon, Mercury, Venus, large differentiated asteroids, and Earth.
The replacement of machines in a serially dependent multi-machine production system

In this paper a heuristic procedure is developed for solving the problem of planning machine replacements for a serially dependent production system. Given a finite planning horizon, the decision-maker wishes to decide (1) which periods, if any, that the entire production system must be shut down in order to make replacements, and (2) what specific machine or machines in the system should be scheduled for replacement during each of these downtime periods. The problem involves a balancing of costs. If the production system is brought down to make one or more replacements a fixed downtime cost is incurred; this cost is independent of the machines replaced during the downtime. In addition, other fixed coats are incurred for each of the machines replaced. Our motivation for scheduling these replacements is to realize lower variable costs for operating the machines. The variable operating costs are assumed to increase as the age or vintage of the machines increases. An optimal replacement policy is one in whic...
Does significant arterial hypoxemia alter vital signs

Abstract Study Objective: To determine the cardiovascular and respiratory effects of arterial hypoxemia in adult volunteers. Design: Prospective, subject-controlled. Setting: University-affiliated hospital. Subjects: 16 awake, unsedated, unanesthetized adult volunteers. Interventions: Inspired oxygen concentration (FIO 2 ) was decreased in decrements to reduce pulse oximeter values to a range of 95% to 90%, 89% to 85%, 84% to 80%, and 79% to 70%. Measurements and Main Results: Heart rate, (HR), blood pressure (BP), respiratory rate (RR), arterial blood pH, gas tensions, and oxyhemoglobin saturation were determined during normoxia and each level of oxyhemoglobin desaturation. FI0 2 was reduced from 21% to 10%. Arterial blood oxyhemoglobin saturation and oxygen tension ranged from 100% to 71% and 103 to 35 mmHg, respectively. There were no significant changes in RR, BP, or HR during the study. Conclusions: HR, BP, and RR are not reliable indicators of arterial hypoxemia in awake volunteers. If this finding is also true for sedated or anesthetized patients, then continuous monitoring with pulse oximetry should be used whenever patients are at risk for arterial hypoxemia. Stable HR, BP, and RR may not eliminate the possibility of significant arterial hypoxemia and impending catastrophic events.
Expression of alpha 7 integrin cytoplasmic domains during skeletal muscle development: alternate forms, conformational change, and homologies with serine/threonine kinases and tyrosine phosphatases.

We recently reported the cloning and sequencing of the alpha 7 integrin chain and its regulated expression during the development of skeletal muscle (Song et al. (1992) J. Cell Biol. 117, 643–657). The alpha 7 chain is expressed during the development of the myogenic lineage and on adult muscle fibers and this suggests that it participates in multiple and diverse functions at different times during muscle development. One interesting portion of this isoform is its cytoplasmic domain; comprised of 77 amino acids it is the largest in the alpha chains thus reported. In these experiments we begin to study the potential functions of the alpha 7 cytoplasmic domain by analyzing homologies between the rat and human sequences, by immunologic studies using an anti-cytoplasmic domain antiserum, and by identifying two alternate forms. In keeping with the nomenclature used to describe the alpha 3 and alpha 6 alternate cytoplasmic domains, we refer to the originally reported species as alpha 7B and the two additional forms as alpha 7A and alpha 7C. These three cytoplasmic domains likely arise as a consequence of alternate splicing. A splice site at the junctions of the transmembrane and cytoplasmic domains is used to generate the alpha 3, alpha 6 and alpha 7 A and B forms. The alpha 7A form RNA contains an additional 113 nucleotides compared to the B form, and a common coding region in the A and B form RNAs is used in alternate reading frames. Part of the coding region of alpha 7B appears to be used as the 3′-untranslated region of the alpha 7A form. The alpha 7C mRNA is 595 nucleotides smaller than the alpha 7B RNA and part of the 3′-untranslated region of the alpha 7B isoform is used as coding sequence in alpha 7C. There is developmental specificity in expression of these alternate mRNAs: alpha 7A and alpha 7C transcripts are found upon terminal myogenic differentiation whereas alpha 7B is present earlier in replicating cells and diminishes upon differentiation. We suggest this selective expression of the alpha 7 cytoplasmic domains underlies the diversity in function of the alpha 7 beta 1 integrin at different stages of muscle development. Immunochemical analyses indicate that the alpha 7B cytoplasmic domain undergoes a change in conformation in response to binding laminin or upon crosslinking initiated with antibody reactive with the integrin extracellular domain. Crosslinking also promotes association of the integrin with the cell cytoskeleton.(ABSTRACT TRUNCATED AT 400 WORDS)
ANALGESIC EFFICACY OF PARENTERAL METKEPHAMID ACETATE IN TREATMENT OF POSTOPERATIVE PAIN

Abstract The analgesic efficacy and side-effects of a single parenteral dose of metkephamid acetate 70 mg were compared with those of pethidine (meperidine) hydrochloride 100 mg and placebo in a double-blind, randomised, controlled clinical trial. 30 out of 32 postoperative patients completed the study—10 in the metkephamid group, 11 in the pethidine group, and 9 in the placebo group. The time-effect curves of summated pain measures and analyses of derived measures all indicated that the analgesic activity of metkephamid 70 mg was significantly greater than that of placebo and not less than that of pethidine 100 mg. The metkephamid group had a greater incidence of side-effects than the other two treatment groups. Some side-effects, such as sensations of heaviness of the extremities and nasal congestion, were peculiar to metkephamid but not distressing.
An extensible interpreter

The purpose of this brief paper is to propose an alternative approach for the implementation of an extensible language. The idea outlined here will be referred to as an extensible interpreter. In this particular case, the term itself constitutes an exceptionally concise description of the basic concept, even though there exists another, equally valid way of viewing the same notion, namely as a strategy for integrating an optimizing compiler into an essentially interpretive system. Regardless of which point of view is preferred, however, both are indicative of the fundamental assumption which underlies the present proposal: that the “semantics” of a programming language must ultimately be defined by means of an interpreter. This is to say that the definition of a given language must finally be formulated in terms of an “abstract machine” which is capable of carrying out, in an appropriate environment, the “unit operations” comprising the semantic primitives that language. Thus, an implementation which reflects the definition of the language in question must necessarily include a realization of this abstract machine, whether it is present implicitly, in the processing performed by the compiler, or whether it appears explicitly. In the latter case, the abstact machine may be represented in the form of a conventional software interpreter, or more directly, by means of a suitable set of micro-instructions, the only distinction being the number of different “layers” of interpretation which are actually interposed between this machine and the supporting hardware. In the context of an extensible language, one can immediately identify the natural instruction set for such an abstract machine: it corresponds to the repertoire of primitive operations provided by the base language. Since it is axiomatic to extensibility that new linguistic elements are constructed by systematic composition of previously defined and/or primitive constructs, the “meaning” of every operation in any subsequent extended language is ultimately defined by its derivation in terms of the operations belonging to the base language. Given that it is, conceptually, the definition of the language which is expected to evolve as a consequence of extension, there are strong motivations for explicitly representing the definition itself in any implementation of that language. The logical point of departure, therefore, is to implement an interpreter for the base language, thereby providing a direct realization of the underlying abstract machine.
Increasing the number of masticatory cycles is associated with reduced appetite and altered postprandial plasma concentrations of gut hormones, insulin and glucose

To determine the influence of masticatory efficiency on postprandial satiety and glycaemic response, twenty-one healthy males were recruited for this randomised cross-over trial. The participants consumed a fixed amount of pizza provided in equal-sized portions by chewing each portion either fifteen or forty times before swallowing. Subjective appetite was measured by appetite questionnaires at regular intervals for 3 h after the meal and plasma samples were collected for the measurement of selected satiety-related hormones, glucose, insulin and glucose-dependent insulinotropic peptide (GIP) concentrations. An ad libitum meal was provided shortly after the last blood sample was drawn and the amount eaten recorded. Compared with fifteen chews, chewing forty times per portion resulted in lower hunger (P= 0·009), preoccupation with food (P= 0·005) and desire to eat (P= 0·002). Meanwhile, plasma concentrations of glucose (P= 0·024), insulin (P< 0·001) and GIP (P< 0·001) were higher following the forty-chews meal. Chewing forty times before swallowing also resulted in a higher plasma cholecystokinin concentration (P= 0·045) and a trend towards a lower ghrelin concentration (P= 0·051). However, food intake at the subsequent test meal did not differ (P= 0·851). The results suggest that a higher number of masticatory cycles before swallowing may provide beneficial effects on satiety and facilitate glucose absorption.
The other side of the orexins: endocrine and metabolic actions

Although it is clear that the orexin/hypocretin peptides have a significant, physiologically relevant role in sleep/wakefulness, a broader picture has emerged indicating metabolic actions that may depend upon both neural and endocrine mechanisms for their manifestation. The ability of exogenous peptide to activate sympathetic tone, increase locomotor activity, and alter feeding behavior, together with the observed alterations in those functions in knockout animals, strongly suggests important neural actions of the endogenous orexins/hypocretins. Likewise, the action of exogenously administered peptides to alter endocrine function, in particular corticotropin release, has now been mirrored by potential endocrinopathies in knockout animals. Thus these pluripotent peptides hold great potential not only for the treatment of human narcolepsy but also to provide insight into the coordinated regulation of multiple physiological systems.
Improving the Leadership Skills of Pre-Service School Librarians through Leadership Pre-Assessment.

School librarian guidelines encourage active leadership in schools. Two ways school librarian educators can encourage school librarians to be leaders are to embed the standards into the certification curriculum and to assess the leadership potential of preservice school librarians in order to adapt the curriculum to their needs. This mixedmethod study examines how a pre-assessment of leadership potential was implemented in a school librarianship certification program that emphasized leadership skills. The results of the study indicate that the leadership pre-assessment implemented during the program application process effectively identified teacher leaders with the potential to be exceptional school librarians. This signifies that leadership pre-assessments can enable school librarian educators to help pre-service school librarians to improve their leadership skills.