cssi/SciSciGPT-SciSciNet huggingface dataset:
Project Management in Real Time: A Service-Learning Project

This article describes a service-learning assignment for a project management course. It is designed to facilitate hands-on student learning of both the technical and the interpersonal aspects of project management, and it involves student engagement with real customers and real stakeholders in the creation of real events with real outcomes. As such, it helps students internalize project management principles and value project management tools. Student teams design and implement plans for events intended to result in significant contributions in support of various charitable organizations. They create the planning and execution documents required of project management teams. The article describes the assignment and its results and discusses some cautions and alternatives.
Neural network modelling of eye compensation during off-vertical-axis rotation

Abstract Compensatory eye motion during off-vertical axis rotation of the head in darkness (OVAR), has been modelled with a neural network. The three layered nework was trained with back-propagation to simulate the estimation of head velocity during OVAR. The network produced good estimates within its training range and predicted the eye velocity versus head velocity characteristics in the monkey. Invariance of the compensation to changes in tilt angle, not fully addressed in previous models, was demonstrated by the network, along with a smooth decline in velocity estimate below a threshold angle. This also agreed well with data from the monkey. Study of the internal units of the network provided insight into the manner in which pattern comparison produced the estimates. In addition, the behavior of the network's units suggests types of behavior that might be looked for through unit recordings in the central nervous system during OVAR.
Modeling Fecal Coliform Bacteria Levels at Gulf Coast Beaches

This study presents and compares two models for predicting fecal coliform levels at Gulf Coast beaches in Louisiana, USA. One was developed using the artificial neural network (ANN) in MATLAB toolbox and the other one was developed based on the multiple linear regression method (MLR). A total of six independent environmental variables, including rainfall, tide, wind, salinity, temperature, and weather type along with eight different combinations of the independent variables are capable of explaining about 76 % of variation in fecal coliform levels for model training data and 44 % for independent data. The findings are obtained from the ANN model and the MLR model using six years of bacteriological and environmental monitoring data. The results show that the ANN model performs consistently better than the MLR model. Applications of the ANN model can significantly reduce potential health risks of fecal pollution to beachgoers. The paper provides new insights into environmental processes responsible for the variation in levels of fecal coliform bacteria in coastal beach waters as well.
Partial purification and kinetic characterization of the microsomal phospholipase A2 from thermally acclimated rainbow trout (Salmo gairdneri).

Phospholipase A2 (PLA2) was extracted from liver microsomal membranes of both 5 and 20°C-acclimated rainbow trout (Salmo gairdneri), using the non-ionic detergent, Triton X-100. Further purification was achieved by precipitation with 35–65% ammonium sulfate followed by gel filtration chromatography in the presence of 0.1% Triton X-100 on Sephadex G-200. These procedures resulted in a 30-fold purification and the removal of all traces of phospholipid from the enzyme of both warm-and cold-acclimated trout. Column elution profiles were similar for both acclimation groups, yielding a molecular weight estimate for the trout liver enzyme of 73,000. Comparisons of activity levels and kinetic parameters of PLA2 from warm-and cold-acclimated fish, indicated that compensation for temperature at nonsaturating substrate concentrations was an attribute of both the particulate (microsomal) enzyme and the lipid-free protein. Cold acclimation resulted in higher activity belowV max due primarily to decreased apparentK m values. These adaptations to temperature could not be attributed to the interaction of the enzyme with the membrane lipids, but were due to qualitative changes in the enzyme that resulted from acclimation. Other adaptive qualities of PLA2, such as reducedK m in response to acute decreases in temperature in warm-acclimated fish, were only apparent in particulate preparations, and thus were a function of the protein-lipid complex. These data suggest that an acclimation-induced increase in the activity of PLA2 may result in the activation of a deacylation-reacylation cycle at cold temperatures.
Can higher hemoglobin prolongs life for patients with kidney disease

Patients with chronic kidney disease (CKD) are at marked increased risk for cardiovascular (CV) morbidity and mortality including heart failure, coronary artery disease, and sudden cardiac death.1 Anemia is a well-known and common disorder in patients with CKD. Moreover, chronically low hemoglobin (Hb) concentration in the blood of patients with CKD is known to be associated with adverse outcomes in general and with increased CV morbidity and mortality in particular. It is hypothesized that anemia caused by the state of CKD results in tissue hypoxia leading to increased myocardial oxygen demand and work leading to left ventricular hypertrophy (LVH) and ischemic heart disease. The consequences of LVH and cardiac ischemia then result in congestive heart failure, myocardial infarction, and arrhythmias leading to fatal events.
Conceptualizing Self with In-Group Stereotypes: Context and Esteem Precursors

Use of internalized social stereotypes of an in-group in self-conceptions was examined. It was proposed that situationally induced salience of sex-group membership would interact with individual self-esteem to influence presence of gender roll stereotypes in the working self-concept of women. Sixty female subjects had their attention focused either on their unique characteristics or on their gender-group conceptions. This manipulation was crossed with self-esteem level. Masculinity and femininity scores from the Bem Sex-Role Inventory were obtained as dependent measures. Results showed that attentional focus interacted with self-esteem level to influence both masculinity and femininity scores. Theoretical and potential practical implications are discussed.
Temperature-dependence of local melting in the myosin subfragment-2 region of the rigor cross-bridge

Abstract We have used α-chymotrypsin as an enzyme-probe to detect local melting in the subfragment-2 region of the cross-bridges of rigor myofibrils and glycerinated psoas fibers. The kinetics of proteolysis and the sites of cleavage were determined at various temperatures over the range 5 to 40 °C by following the decay of the myosin heavy chain and the rates of appearance of light meromyosin fragments, using electrophoresis on sodium dodecyl sulfate-containing polyacrylamide gels. Cleavage occurs primarily at the 72,000 M r and 64,000 M r (per polypeptide chain from the C terminus of myosin) sites within the light meromyosin-heavy meromyosin hinge domain of the subfragment-2 region, under all experimental conditions. At pH 8.2 to 8.3 and at low divalent metal ion (0.1 m m ), where the actin-bound cross-bridges are thought to be released from the thick filament surface, the intrinsic cleavage rate constant ( k ) increases markedly as the temperature is raised. This suggests substantial thermal destabilization of the released cross-bridge in the intact contractile apparatus. Addition of divalent metal ion (10 m m ) lowers the cleavage rate and shifts the k versus temperature profile to higher temperatures. Normalized rate constants for chymotryptic cleavage within the subfragment-2 hinge region of released cross-bridges (pH 8.2, low divalent metal) of rigor fibers were markedly lower than activated fibers at all temperatures investigated (5 to 40 °C). Results show that conformational melting within the subfragment-2 hinge region is amplified on activation and is well above that observed when the actin-attached rigor bridge is passively released from the thick filament surface.
Isolation of proteins by gel filtration in 6M guanidinium chloride: application to RNA tumor viruses.

Abstract Separation of RNA tumor virus proteins by gel filtration in 6 m guanidinium chloride indicates that this method will effectively separate polypeptides in milligram amounts whose molecular weights differ by as little as 15 percent. Such separations are achieved because proteins in 6 m guanidinium chloride have a random coil conformation with diffusion coefficients considerably smaller than the corresponding native proteins. Consequently, protein bands that emerge from a gel filtration column in 6 m guanidinium chloride are remarkably sharp. A 60–70% yield of renatured RNA tumor virus proteins could be obtained following dialysis against a dilute solution of mercaptoethanol. The major proteins of avian RNA tumor viruses were obtained as pure components by gel filtration in 6 m guanidinium chloride. Mammalian RNA tumor viruses appear to have a more complex protein structure, since, in some cases, additional purification was required to obtain the pure proteins. This method of protein separation might be used as the initial stop in the isolation of components from other biological macrostructures.
Planetary and Solar Radio Emission at 11 Meters Wavelength

Observations are described of radio emissions from the Sun, Jupiter, and Venus during 1956 and early 1957 at a wavelength of 11 meters. Records are presented of solar 11-meter radiation at the time of a large (importance 3) flare on August 31, 1956, and during other periods of solar activity. The effect of scintillation on records of radio stars also is illustrated. A number of records of impulsive radiation from Jupiter at both slow and fast recorder speeds is shown. The radiation is of a bursty or intermittent nature which can be classified into two main types: one which may persist for several seconds and produces a rumbling sound in the loudspeaker and another which is of very short duration (10 milliseconds or less) and produces a cracking or clicking sound. Many of the short pulses consist of distinct pairs or triplets which fall into two main groups, one having pulse separations of about one-quarter second and the other, pulse separations of about one tenth this value. An echo mechanism to explain the multiple pulses is postulated and observed trends in pulse separation compared to those expected with such a mechanism. The stronger Jupiter pulses indicate a peak radiated radio power at the source of the order of 10 kilowatts per cps bandwidth.
An evaluation of centerline of flow measurement techniques to assess migration after thoracic endovascular aneurysm repair.

Objective To validate a means by which migration of thoracic stent grafts can be reliably detected and quantified. Methods Patients treated for thoracic aneurysms (without dissections) with either the Cook Zenith TX1/TX2 or the Gore TAG device were retrospectively reviewed. Patients with digital imaging data at a baseline study (discharge or 1-month computed tomographic scan) and a minimum of 6 months' follow-up were evaluated on a three-dimensional workstation. Centerline of flow (CLF) calculations were used to determine length measurements to establish distances from native vascular landmarks (left common carotid artery, left common carotid artery, and celiac artery) to the proximal and distal aspects of the fixation systems of stent grafts. Patients with evidence of fixation system migration (>10 mm of movement) or increasing thoracic aortic lengths (left common carotid artery to celiac artery distance) were subjected to more detailed reviews. Results Of 194 patients evaluated (133 Zenith and 61 TAG), 46 were treated for dissections and excluded. Fifty-seven patients did not have a digital baseline study and available DICOM data for follow-up imaging at 6 months or later or had died before such follow-up imaging. The remaining 91 patients underwent assessment for device migration. Analyses were conducted on 19 patients at 6 months, on 42 at 12 months, on 12 at 24 months, on 13 at 36 months, and on 5 at 48 months. CLF analysis noted more than 10 mm of caudal movement of the proximal device in 10 patients and cranial movement of the distal device in 3 patients. When this subset was further scrutinized with regard to morphologic changes remote from the prosthesis and in the context of the overall aortic repair (such as elephant trunk grafts), only four patients had movement of the proximal or distal fixation system with respect to the initially deployed location. Two-dimensional axial image analysis identified migration in only one of the four patients with CLF-detected fixation system movement. Conclusions The importance of early migration detection cannot be overstated given the potential to avert consequences as evidenced by analyses of counterpart abdominal aortic aneurysm devices. In vivo thoracic device analysis is more complex than that for devices used for infrarenal aneurysms. Distance calculations based on CLF measurements may overestimate the frequency of true migration, yet they serve as a reasonable initial screening tool. The resultant subset of patients then must undergo a more detailed evaluation of device position in the context of the aortic morphology to differentiate true migration from devices that maintain stable fixation system positions.
Vesicle-associated membrane protein isoforms in the tiger salamander retina.

Vesicle associated membrane protein (VAMP; also known as synaptobrevin) is a key component of the core complex needed for docking and fusion of synaptic vesicles with the presynaptic plasma membrane. Recent work indicates that the precise complement of presynaptic proteins associated with transmitter release and their isoforms vary among synapses, presumably conferring specific functional release properties. The retina contains two types of vesicular synapses with distinct morphologic, functional, and biochemical characteristics: ribbon and conventional synapses. Although the precise complement of presynaptic proteins is known to differ between conventional and ribbon synapses and among conventional synapses, the distribution of VAMP isoforms among retinal synapses has not been determined. The expression and localization of VAMP isoforms in the salamander retina, a major model system for studies of retinal circuitry, was examined by using immunocytochemical and immunoblotting methods. Both methods indicated that at least two VAMP isoforms were expressed in salamander retina. One isoform, recognized by an immunoglobulin M antibody that recognizes both mammalian VAMP-1 and VAMP-2, was associated with photoreceptor and bipolar cell terminals as well as many conventional synapses, and probably corresponds to mammalian VAMP-2. A different VAMP isoform associated with a subset of amacrine cells, was recognized only by antibodies directed against the N-terminus of mammalian VAMP-2. An antiserum directed against the N-terminus of mammalian VAMP-1 did not specifically recognize any salamander VAMPs in either immunocytochemical or immunoblotting experiments. Heterogeneous distribution of VAMP isoforms among conventional retinal synapses was confirmed by double labeling for synapsin I, a marker for conventional synapses. These studies indicate that VAMP isoforms are expressed heterogeneously among retinal synapses but cannot account for the differences in transmitter release characteristics at ribbon and conventional synapses. These results also corroborate previous studies in Xenopus indicating that the N-terminus of nonmammalian VAMP isoforms differs from their mammalian counterparts. J. Comp. Neurol. 431:424‐436, 2001. © 2001 Wiley-Liss, Inc. Indexing terms: synaptobrevin; synapse; photoreceptor; bipolar cell; amacrine cell
Comparison of S100B and NSE between cardiac surgery and interventional therapy for children.

This study aimed to compare the release of S100B and NSE between cardiac surgery and interventional therapy for children and to investigate whether S100B serum concentration correlates with cardiopulmonary bypass in children. For this study, 40 children with congenital heart disease were selected and assigned to two groups: group A (20 children undergoing surgical therapy) and group B (20 children undergoing interventional therapy). In group A, blood samples were drawn 10 min after the induction of anesthesia, immediately after aortic cross-clamping, immediately at the end of cardiopulmonary bypass (CPB), immediately at the end of the operation, then 6 and 24 h after the operation. In group B, blood samples were drawn 10 min after the induction of anesthesia, immediately at the end of the procedure, then 6 and 24 h after the procedure. In group A, S100B plasma levels during the perioperative period and 6 h after the operation were higher than the preoperative level (p 0.05). The perioperative cerebral impairment indirectly evaluated by the release of NSE and S100B protein is greater in children undergoing CPB than in children undergoing interventional therapy. The release of S100B had a strong correlation with the durations of CPB and aortic cross-clamping in children.
The effect of stimulus delivery technique on perceived intensity functions for taste stimuli: implications for fMRI studies.

Classic psychophysical studies have provided significant information on the psychophysical functions for taste stimuli. With the advent of fMRI, studies are being conducted that provide insight into central processing of gustation in humans. However, fMRI experiments impose physical limitations on stimulus delivery. In the present study, we compared psychophysical functions relating perceived intensity to concentration, derived from previous studies that used the traditional sip-and-spit and dorsal flow delivery techniques, to psychophysical functions generated in this study using a simulated stimulus delivery technique (SSDT). The SSDT delivered minute quantities of taste stimuli to the dorsal surface of the tongue, just as in an fMRI scanner. As was hypothesized, the results indicated that slopes of intensity functions were dependent on the type of stimulus delivery technique. The SSDT resulted in slopes that were more similar to those generated by dorsal flow than by sip-andspit stimulus delivery techniques, suggesting the importance of considering the influence of stimulus delivery on psychophysical response in designing and interpreting experiments.
Fate of 2,4,6-trichloro-(14C)-phenol bound to dissolved humic acid

Abstract Batch microcosms were utilized to evaluate binding of 2,4,6-trichlorophenol (TCP) to dissolved humic acid (HA). Biodegradation of 2,4,6-TCP was then evaluated after addition of a bacterial culture previously acclimated to the substrate. Gel chromatography (size exclusion) was used to separate HA-bound 2,4,6-TCP from free (unbound) 2,4,6-TCP by molecular size before quantitative analysis. Dissolved HA can interact with free 2,4,6-TCP, forming an HA/TCP association in solution. Equilibrium isotherms of 2,4,6-TCP for dissolved HA are linear for 2,4,6-TCP concentrations up to 1000 μg/l and HA concentrations up to 100 mg/l. Distribution coefficients of 2,4,6-TCP for HA vary with dissolved humic concentration. Coefficients decreased with increasing HA concentration indicating a change in HA sorption characteristics with concentration. Acclimated bacteria, Pseudomonas aeruginosa , can mineralize up to 60% of the total 2,4,6-TCP in solution, however, total mineralization decreased with increasing HA concentration. Overall mineralization in HA-containing solutions was 5–15% less than in HA-free solutions. Biodegradation of free 2,4,6-TCP was very rapid while biodegradation of HA-bound 2,4,6-TCP was much reduced and appeared to be desorption controlled.
Failure of Operative Treatment for Glenohumeral Instability: Etiology and Management

Failure of primary shoulder stabilization procedures is often related to uncorrected anatomic pathology. Orthopaedic surgeons must recognize excessive capsular laxity or large glenohumeral bone defects preoperatively to avoid recurrence of instability. When history, physical examination, and radiographic evaluation are used in conjunction, patients at risk for failure can be identified. The instability severity index score permits precise identification of patients at risk. When treating patients in whom prior surgical intervention has failed, the success of revision procedures correlates to the surgeon's ability to identify the essential pathology and use lesion-specific treatment strategies. Revision procedures remain technically demanding. Keen preoperative and intraoperative judgment is required to avoid additional recurrence of instability after revision procedures, particularly because results deteriorate with each successive operation. Glenoid or humeral defects with greater than 25% bone loss compromise stability provided through the mechanism of concavity compression. These defects must be specifically addressed to avoid recurrence of instability. We prefer anatomic reconstruction techniques combined with capsulolabral repair and, if bone defects are present, anatomic reconstruction with osteochondral allograft.
Differences between young and aged mice in suceptibility to Friend virus

Friend virus (FV) is a murine leukemia virus that infects progenitor red blood cells and causes an erythroleukemia in susceptible mouse strains, resulting in splenomegaly. Several genetic loci of the host have been identified that affect erythroleukemia development, differentiation status of target cells and virus replication. Since age may change expression of these loci, age may affect FV disease. To explore this possibility, FV expression in four genetically diverse strains of mice of different ages was examined. Extent of viral replication and of disease were evaluated by measuring spleen focus forming units (SFFU), spleen weight and reverse transcriptase (RT) activity in target organs. Young DBA/2 and (C57BL/6 x DBA/2)F1 mice exhibited a greater level of virus expression than their aged counterparts in all parameters investigated. Young CBA/Ca mice had slightly higher spleen weights and SFFU values than aged CBA/Ca mice, but a definitive age-related change was not observed in the RT activity of the target organs. C57BL/6 mice, which are genetically resistant to the development of FV-induced erythroleukemia, exhibited a limited degree of virus replication that was not effected by the age of the animal. Our results indicate that the age of the mouse, as well as the genetic background, can contribute to the level of susceptibility to FV.
Investigation of declared seating preference and measured cognitive performance in a sunlit room

Abstract Current daylighting standards are not sufficient to guarantee a high-quality daylighting experience as they fail to take the behavior of building occupants into consideration. The way that a daylit room is appreciated and used has not been fully explored, especially under sunlighting conditions. This research is the first of its kind to assess how the distance between a subject and a sun patch on the floor is related to a broad range of behavioral responses, including conclusive preference and measured cognitive performance. One hundred subjects participated in a controlled experiment in a work setting. Investigations of the declared preferences of seating area and subjects' cognitive performances indicated that people are not always aware of the environmental factors that influence their behavior. Subjects were generally attracted to sunlight and outdoor views, but they did not necessarily perform best in these preferred areas. Privacy and a sense of control were two hidden factors that greatly affected subjects' decisions and performances. Current daylighting literature and design practice do not pay adequate attention to such factors as sense of visual control or privacy in the design of rooms. On the other hand, the perceived problem of visual glare caused by sunlight penetration did not affect performance as much as subjects believed it would. An additional result suggested that individual behaviors were more affected by environmental elements than were group activities.
Analysis of Internet Download Manager for collection of digital forensic artefacts

Internet Download Manager (IDM) provides accelerated download speed and flexibility in features. Its attractiveness lies behind video content processing and automatic handling of downloads. This paper analyzes IDM activities recorded across multiple files that includes Windows Registry, history and log files from artefacts collection view point. The tools and techniques used for extracting evidence are also elaborated. In case of download managers, the foremost concerns are installation location, download path, downloaded file, URL address, login credentials for password protected websites, date and time the activity was performed. This enables digital forensic investigators to envisage and deduce suspicious activities.
Porewater pressure increases in soil and rock from underground chemical and nuclear explosions

Abstract A review and analysis of chemical and nuclear explosive-induced porewater pressure increases and induced rise in groundwater table elevations (groundwater mounding) is presented. Our analysis indicates that residual pore pressure increases and groundwater mounding can be induced by underground chemical and nuclear explosions to scaled distances of 879 m/(kt) 1 3 . This relationship is linear over seven orders of magnitude of explosive energy ranging from a 0.01 kg chemical explosion to a 100 kt nuclear explosion and is valid for a wide variety of saturated geological profiles. Underground chemical explosions, and probably underground nuclear explosions have the potential to induce liquefaction of water-saturated soils to scaled distances of about 260 m/(kt) 1 3 .
On-line algorithms for locating checkpoints

Motivated by applications in data compression, debugging, and physical simulation, we consider the problem of adaptively choosing locations in a long computation at which to save intermediate results. Such checkpoints allow faster recomputation of arbitrary requested points within the computation. We abstract the problem to a server problem in whichk servers move along a line in a single direction, modeling the fact that most computations are not reversible. Since checkpoints may be arbitrarily copied, we allow a server to jump to any location currently occupied by another server. We present on-line algorithms and analyze their competitiveness. We give lower bounds on the competitiveness of any on-line algorithm and show that our algorithms achieve these bounds within relatively small factors.
Influence of vitamins and coliform bacteria on sulfaguanidine tolerance by young chickens.

ConclusionsThe death rate among baby chicks fed an adequate ration plus sulfaguanidine at the level of 1 g per 100 g body weight per day is less than half that occurring when a mixture of p-aminobenzoic acid, thiamin and riboflavin or a suspension of E. coli are administered with the drug. These facts, together with the tendency of both the vitamins and bacterial suspension to sustain the coliform bacteria in the feces in the presence of an inhibitory concentration of the drug, suggest that the tolerance of sulfaguanidine by young birds may be related to the activities of the coliform bacteria in the intestinal tract.Our findings do not, in themselves, constitute a contra-indication to the clinical use of sulfaguanidine, for the level of drug employed here is much in excess of the effective therapeutic dosage. They serve only to emphasize the apparently fundamental and complex relationship of vitamins and intestinal bacteria to the action of sulfaguanidine in vivo.
High temperature oxidation of molybdenum in water vapor environments

Abstract Molybdenum has recently gained attention as a candidate cladding material for use in light water reactors. Its excellent high temperature mechanical properties and stability under irradiation suggest that it could offer benefits to performance under a wide range of reactor conditions, but little is known about its oxidation behavior in water vapor containing atmospheres. The current study was undertaken to elucidate the oxidation behavior of molybdenum in water vapor environments to 1200 °C in order to provide an initial assessment of its feasibility as a light water reactor cladding. Initial observations indicate that at temperatures below 1000 °C, the kinetics of mass loss in water vapor would not be detrimental to cladding integrity during an off-normal event. Above 1000 °C, degradation is more rapid but remains slower than observed for optimized zirconium cladding alloys. The effect of hydrogen–water vapor and oxygen–water vapor mixtures on material loss was also explored at elevated temperatures. Parts-per-million levels of either hydrogen or oxygen will minimally impact performance, but hydrogen contents in excess of 1000 ppm were observed to limit volatilization at 1000 °C.
Challenges in Monte Carlo track structure modelling.

AbstractPurpose: Although great progress has been made, numerous challenges remain in the development of Monte Carlo (MC) charged-particle track structure simulation models. Such models have evolved from the simple gas phase target models to those using condensed phase interaction data coupled with complex targets representing cellular and molecular constituents of mammalian tissue. A wide choice of MC models is now available ranging from those based on the physics of continuous slowing down, to simulations following each interaction on an event-by-event basis. The choice of code depends largely on requirements for computational speed, and the degree of detail required; however, one must be continuously vigilant to recognise the inherent limitations of the model chosen. Conclusions: There remain numerous questions of the accuracy and completeness of the interaction physics that present challenges to MC modellers. Recent evidence suggests that the yields of electrons with energies less than a few hundred e...
Global sources, lifetimes and mass balances of carbonyl sulfide (OCS) and carbon disulfide (CS2) in the earth's atmosphere

Abstract Emissions of carbonyl sulfide (OCS) and carbon disulfide (CS2) from natural and anthropogenic sources have been estimated consistent with the observed latitudinal and vertical distributions of these trace gases. Anthropogenic emissions appear to be a small part (⩽ 25 %) of the yearly emissions of OCS and CS2. Oceans and soils are the largest sources, representing about 50 % of the yearly emissions of OCS. Biomass burning is perhaps the largest anthropogenic source, while coal-fired power plants and automobiles contribute small amounts. Chemical uses may be the largest anthropogenic source of CS2. The results suggest that the lifetime of OCS is about 2 years and of CS2 about 12 days.
Intestinal Transport of Weak Electrolytes Evidence in Favor of a Three-Compartment System

A study has been made of the transmural fluxes of benzoic, phenylacetic, and pentanoic acids, benzylamine, hexylamine, and D-amphetamine across rat jejunum incubated in vitro. The M to S fluxes of the weak acids were greater than their corresponding S to M fluxes, and the S to M fluxes of the weak bases were larger than their M to S fluxes. These patterns of asymmetric movements were observed when the transmural electrical potential difference was clamped at 0 mV, and when the pH values of the mucosal and serosal fluids were identical. The effects of a weak acid on the fluxes of other weak electrolytes were qualitatively similar when the effector weak acid was added to the mucosal fluid, and when it was added to the serosal fluid. But the effects of a weak base on the fluxes of other weak electrolytes were dependent upon its location, and the interactions observed when the effector weak base was added to the mucosal fluid were qualitatively different than those seen when it was added to the serosal fluid. The interactions between weak electrolytes could readily be explained in terms of the function of a system of three compartments in series, in which the pH of the intermediate compartment is greater than that of the bulk phases. But these observations could not be explained in terms of an analogous system involving an intermediate compartment of low pH, or in terms of a carrier mediated system. The transport function of the three-compartment system can be described in the form of an equation, and it is found that a pH difference of less than 0.5 unit may explain our observations on weak electrolyte transport.
PC program implementing an alternative to the paired t-test which adjusts for regression to the mean.

In many biomedical research contexts, treatment effects are estimated from studies based on subjects who have been recruited because of high (low) measurements of a response variable, e.g., high blood pressure or low scores on a stress test. In this situation, simple change scores will overestimate the treatment effect; and the use of the paired t-test may find significant change due not to the treatment per se but, rather, due to regression towards the mean. A PC program implementing a procedure for adjusting the observed change for the regression effect in simple pre-test-post-test experiments is described, illustrated, and made available to interested readers. The method is due to Mee and Chua (Am Stat, 45 (1991) 39-42) and may be considered as an alternative to the paired t-test which separates the effect of the treatment from the so-called regression effect.
Eye movements of monkeys during learning-set formation

Eye movements of stump-tailed monkeys were measured during learning of a long series of two-choice pattern discrimination problems. The amount of scanning per trial (shifts in visual fixation from one pattern to the other) and the duration of individual fixations on the patterns increased during the course of learning-set formation and (except for the amount of scanning by some animals) remained high during the prolonged training following learning-set formation. Some of the changes in eye movements were different from those seen during the learning of single discrimination problems, a difference that possibly reflects cognitive processes specific to the learning-set task.
Correction to "Nonreciprocal tunnel diode distributed amplifier"

In the above-named work (ibid., vol. EC-14, pp. 174-175, March 1967), on page 175 the diode admittance Ys expression is corrected. The maximum line length is then affected so a corrected expression replaces the one originally given.
Reading, writing, arithmetic, and computing

The promise of technology has always been an increase in productivity. Labor-intensive activities become machine-intensive. It seems likely that this traditional scenario applies to technology and education, probably the most labor-intensive of human activities. New communications technology, new information-processing technology and new systems for creating and validating machine-administered courses of instruction will surely lead to cost reductions and greater personal convenience and individualization.
“Growing Up” Children: Current Child‐Rearing Practices Among Immigrant Jamaican Families

Purpose To explore and describe current child-rearing practices within immigrant Jamaican families living in the United States. Methods This ethnographic study (N = 16, ages 9-60+) sought to gain an emic perspective of participants' experience with the phenomenon. Interpretive interactionism as a method looked at the process of child rearing in order to uncover meaning of significant events related to this practice. Findings Historical factors affecting the parents' own growing up experience and their experience with and perception of dominant culture values guided their child-rearing practices. Conclusions The goal of child rearing for this immigrant group centered on raising a spiritual, respectful, knowledgeable, and competent child who would be equipped with necessary skills to survive in this society.
Test of the linearity of quantum mechanics in an atomic system with a hydrogen maser.

We extend a nonlinear generalization of quantum mechanics, recently formulated by Weinberg, to systems of composite spin, such as atoms. We have used hydrogen (H) masers to set a limit of 3.7\ifmmode\times\else\texttimes\fi{}${10}^{20}$ eV (8.9 \ensuremath{\mu} Hz) on the magnitude of a nonlinear correction to the quantum mechanics of atomic spins. This result is of comparable magnitude to the limit recently set in a single-valued (nuclear) spin system. In the absence of nonlinear effects, the experiment provides a new and stringent test of H-maser clock performance and the applicability of standard maser theory.
Recognition without picture identification: Geons as components of the pictorial memory trace

Participants viewed a list of black-and-white line drawings and were then presented with a picture fragment identification task in which half of the fragments corresponded to studied pictures and half corresponded to unstudied pictures. In addition to trying to identify each picture fragment, participants gave a rating to indicate the likelihood that the fragment came from a studied picture. When participants could not identify the picture fragments, they were still able to discriminate between fragments that came from studied pictures and fragments that came from unstudied pictures (as shown by their recognition ratings), but only when the fragments contained information about the geometric components (geons) that underlay the original pictures. No recognition without identification was found when the fragments contained only line segment information.
Characterization and visualization of sophisticated scanning attacks

Detection of sophisticated stealthy network scans requires analyzing large amounts of network data collected over long periods of time. The sheer volume of the data prohibits efficient detection from a pure algorithmic approach. However timely detection of such sophisticated scanning attacks is critical since the attacker employing these approaches is usually well-resourced and potentially can bring high impact to the network than a naive attacker can. To detect such sophisticated scans we propose the integration of algorithmic detection and visualization for human detection to simultaneously optimize computational complexity and human analyst time. The proposed approach provides real world detection capabilities without excessive computation overhead. We characterize the features of scanning attacks in a graph theory context, propose efficient graph algorithms to extract these features in real time, employ visualization techniques to show the relevant multidimensional characteristics, and provide test scenarios to show that the proposed work is more efficient and effective than previous approaches.
Cortical projection neurons: sprung from the same root

Whether cortical projection neurons (CPNs) are generated by multipotent or fate-restricted progenitors is not completely understood. In this issue of Neuron, Guo et al. (2013) provide evidence that mouse Fezf2-expressing radial glial cells are multipotent progenitors that sequentially generate all major CPN subtypes and glia.
Historic aspects of human susceptibility to leprosy and the risk of conjugal transmission

Estimates of genetic susceptibility to leprosy were made in the past from observational reports in familial settings using descriptive epidemiologic data. Risk of conjugal transmission of leprosy (from one spouse to another) has been estimated between 1-10% and is thought to occur in 3-5% of spouses exposed to untreated lepromatous disease in the partner. Risk of secondary transmission is presumed higher in other family members than for the conjugal partner. This belief has become dogma to many leprologists who may no longer know the basis for this estimation. This article reviews the historic epidemiologic descriptions of risk for leprosy transmission in married couples compared to other family members. Although uncommon, conjugal leprosy occurs and at higher rates in populations with traditional familial intermarriage and consanguinity.
Aging, Cohorts, and Verbal Ability

Methods. We examined age-related patterns in a measure of verbal ability using 14 repeated cross-sectional surveys from the General Social Survey (GSS) over a 24-year period. Results. The raw GSS data show the expected age-related growth and decline in vocabulary knowledge, but these age differences are reduced when adjusted for cohort differences. There is evidence of small age-related patterns in vocabulary knowledge within cohorts, but the curvilinear contributions of aging to variation in verbal scores account for less than one-third of 1 % of the variance in vocabulary knowledge, once cohort is controlled. Cohort differences in schooling contribute substantially to this effect. Discussion. Within-age-group variation in vocabulary knowledge is vastly more important than age differences per se, and the complexities of the relationship of verbal skills to historical differences in the experience of schooling present an interesting avenue for future research.
Evaluation of epidemiological factors in survival of patients with de novo myelodysplastic syndromes

Myelodysplastic syndromes (MDS) prognosis is currently based solely on clinical parameters. The identification of additional factors associated with MDS outcome could be used to further improve the current scoring system such as the International Prognostic Scoring System (IPSS). The present study evaluates the role of epidemiological markers as predictors of survival for 365 adult de novo MDS patients. Multivariable Cox regression analysis was used to estimate overall survival. Median follow-up time was 22 months. At the time of last follow-up, 271 patients (74.3 %) had died. For all MDS patients, medium–high lifetime occupational agrochemical exposure (HR 1.85, CI 1.19–2.89) remained as an independent predictor of MDS survival. Stratified analysis by gender showed that ≥25 pack-years smoked (HR 1.44, CI 1.001–2.09) and medium–high lifetime occupational agrochemical exposure (HR 1.84, CI 1.15–2.97) were independent predictors of MDS survival in men, but not in women. For MDS patients stratified by IPSS categories, ≥25 pack-years smoked (HR 1.75, CI 1.005–3.06) was an independent predictor for intermediate 1 IPSS risk group only, and medium–high lifetime occupational agrochemical exposure was associated with increased mortality (HR 4.36, CI 1.20–15.8) in the high IPSS risk group. Smoking and lifetime occupational agrochemical exposure may play a role in MDS survival. Incorporating relevant epidemiological markers with known clinical predictors of outcome may help physician stratify patients and customize treatment strategies to improve the outcome of MDS.
Assessing explanatory style: the content analysis of verbatim explanations and the Attributional Style Questionnaire.

Summary-We compare two methods of assessing explanatory style-the content analysis of verbatim explanations (CAVE) and the Attributional Style Questionnaire (ASQ). The CAVE technique is a method that allows the researcher to analyze any naturally occurring verbatim materials for explanatory style. This technique permits the measurement of various populations that are unwilling or unable to take the ASQ. We administered the ASQ and Beck Depression Inventory (BDI) to 169 undergraduates and content analyzed the written causes on the ASQ for explanatory style by the CAVE technique. The CAVE technique correlated 0.71 with the ASQ (P < 0.0001. n = 159) and -0.36 with BDI (P c 0.0001, n = 159). The ASQ correlated -0.51 with the BDI (P < 0.0001, n = 160). Both the CAVE technique and the ASQ seem to be valid devices for assessing explanatory style. Explanatory style is the habitual pattern of explanations an individual makes for good and bad events. According to the reformulation of the learned helplessness model, individuals with a pessimistic explanatory style are more likely to display helplessness deficits when confronted with a bad event than individuals with an optimistic explanatory style (Abramson, Seligman and Teasdale, 1978; Seligman, Abramson, Semmel and von Baeyer, 1979). When they experience bad events individuals who habitually construe the causes of bad events as internal, stable, and global (“it’s my fault, it’s going to last forever, and it’s going to undermine everything I do”) should be more susceptible to helplessness deficits than those with the opposite style. The Attributional Style Questionnaire (ASQ; Seligman et al., 1979; Peterson, Semmel, von Baeyer, Abramson, Metalsky and Seligman, 1982), a questionnaire in which Ss generate a cause and then rate the cause they generate on a 1-7 scale for internality, stability and globality, is the primary instrument for
Some observed queue discharge features at a freeway bottleneck downstream of a merge

Details of traffic evolution were studied upstream and downstream of a freeway bottleneck located near a busy on-ramp. It is shown that on certain days the bottleneck became active upon dissipation of a queue emanating from somewhere further downstream. On such occasions, the bottleneck occurred at a fixed location, approximately one kilometer downstream of the merge. Notably, even after the dissipation of a downstream queue, the discharge flows in the active bottleneck were nearly constant, since the cumulative counts never deviated much from a linear trend. The average bottleneck discharge flows were also reproducible from day to day. The diagnostic tools used in this study were curves of cumulative vehicle arrival number versus time and cumulative occupancy versus time constructed from data measured at neighboring freeway loop detectors. Once suitably transformed, these cumulative curves provided the measurement resolution necessary to observe the transitions between freely flowing and queued conditions and to identify some important traffic features.
The highs and lows of cannabinoid receptor expression in disease: mechanisms and their therapeutic implications

Alterations in the endogenous cannabinoid system have been described in almost every category of disease. These changes can alternatively be protective or maladaptive, such as producing antinociception in neuropathic pain or fibrogenesis in liver disease, making the system an attractive therapeutic target. However, the challenge remains to selectively target the site of disease while sparing other areas, particularly mood and cognitive centers of the brain. Identifying regional changes in cannabinoid receptor-1 and -2 (CB(1)R and CB(2)R) expression is particularly important when considering endocannabinoid system-based therapies, because regional increases in cannabinoid receptor expression have been shown to increase potency and efficacy of exogenous agonists at sites of disease. Although there have been extensive descriptive studies of cannabinoid receptor expression changes in disease, the underlying mechanisms are only just beginning to unfold. Understanding these mechanisms is important and potentially relevant to therapeutics. In diseases for which cannabinoid receptors are protective, knowledge of the mechanisms of receptor up-regulation could be used to design therapies to regionally increase receptor expression and thus increase efficacy of an agonist. Alternatively, inhibition of harmful cannabinoid up-regulation could be an attractive alternative to global antagonism of the system. Here we review current findings on the mechanisms of cannabinoid receptor regulation in disease and discuss their therapeutic implications.