cssi/SciSciGPT-SciSciNet huggingface dataset:
Capacitive Coulter Counting: Detection of Metal Wear Particles in Lubricant Using a Microfluidic Device

A microfluidic device based on the capacitance Coulter counting principle to detect metal debris particles in lubricant oil is presented. The device scans each individual metal debris particle as they pass through a microfluidic channel by monitoring the capacitance change. We first proved the feasibility of using the capacitance Coulter counting principle for detecting metal particles in a fluidic channel. Next, we tested the microfluidic device with aluminum abrasive particles ranging from 10 to 25 µm; the testing results show the microfluidic device is capable of detecting metal wear particles in low-conductive lubricant oil. The design concept demonstrated here can be extended to a device with multiple microchannels for rapid detection of metal wear particles in a large volume of lubricant oil.
CLL and activated NF-κB: living partnership

In this issue of Blood , Hewamana and colleagues from Professor Chris Pepper's laboratory present an important link between NF-κB activity and CLL-cell survival; their findings open the door to a new, potentially prognostic factor for this disease. NF-κB, given its role in cell growth and
In vivo imaging studies shed light on germinal-centre development

Affinity maturation of antibodies during the course of an adaptive immune response requires germinal centre (GC) formation within B-cell follicles. Much of the current understanding of GC function has been derived from histology, but these static views have left unresolved many questions about cell movement in GCs. In this Progress article, we describe how several recent studies using time-resolved multiphoton microscopy to track GC B-cell movement within lymph nodes have shed light on the processes that influence GC B-cell dynamics.
IONIC TRANSFER ACROSS THE ISOLATED FROG LARGE INTESTINE

The unidirectional fluxes of sodium, chloride, and of the bicarbonate and CO2 pair were determined across the isolated large intestine of the bullfrog, Rana catesbiana. The isolated large intestine of the frog is characterized by a mean transmembrane potential of 45 mv., serosal surface positive with respect to mucosal. The unidirectional sodium flux from mucosal to serosal surface was found to be equal to the short-circuit current, thus the net flux was less than the simultaneous short-circuit current. This discrepancy between active sodium transport and short-circuit current can be attributed to the active transport of cation in the same direction as sodium and/or the active transport of anion in the opposite direction. The unidirectional fluxes of chloride and the bicarbonate and CO2 pair revealed no evidence for active transport of either anion. A quantitative study of chloride fluxes at 45 mv. revealed a flux ratio of 1.8 which is considerably less than a ratio of 6 expected for free passive diffusion. It was concluded that a considerable proportion of the isotopic transfer of chloride could be attributed to "exchange diffusion." Study of the electrical properties of the isolated frog colon reveals that it can be treated as a simple D. C. resistance over the range of -20 to +95 mv.
Cocaine Induced Locomotor Activity is Increased by Prior Handling in Adolescent but not Adult Female Rats

Abstract Adolescence is a period of transition that is associated with increased levels of stress and a heightened propensity to initiate drug use. Neuronal development is still occurring during this transitional period, which includes the continued development of the dopamine system during the adolescent period. In the present study, the effects of pre-test handling on cocaine-induced locomotor activity were investigated among female adolescent and young adult rats upon presentation to a novel environment. On postnatal days (PND) 41–44 and 56–59 animals were handled (b.i.d.) in the colony room for 3 min. On PND 45 or PND 60, animals were removed from the colony room, weighed, and administered an acute injection of either cocaine or saline and presented to a novel environment where behavior was recorded for 30 min. Adolescent females (PND 45) that were handled prior to cocaine administration demonstrated elevated levels of cocaine-induced activity relative to their age-matched non-handled counterparts and also to their handled-adult counterparts. In contrast, among non-handled animals, young adults (PND 60) exhibited elevated drug-induced locomotion at several time points during the trial. Non-handled adolescent animals demonstrated the previously described “hyporesponsive” behavioral profile relative to their non-handled adult counterparts. The results from the present experiment indicate that adolescent animals may be more sensitive to basic laboratory manipulations such as pre-test handling, and care must be taken when utilizing adolescent animals in behavioral testing. Handling appears to be a sensitive manipulation in elucidating differences in cocaine-induced behavioral activation between ages.
QUASIGROUP HOMOTOPIES, SEMISYMMETRIZATION, AND REVERSIBLE AUTOMATA

There have been two distinct approaches to quasigroup homotopies, through reversible automata or through semisymmetrization. In the current paper, these two approaches are correlated. Kernel relations of homotopies are characterized combinatorically, and shown to form a modular lattice. Nets or webs are exhibited as purely algebraic constructs, point sets of objects in the category of quasigroup homotopies. A factorization theorem for morphisms in this category is obtained.
A method for automated analyses of the activities of trypsin, chymotrypsin and their inhibitors

Abstract Methods for the automated analyses of the activity of trypsin and chymotrypsin and their inhibitors using l -BAPA and l -GPNA, respectively, as substrates are described.
Cortical motor potential in monkeys before and after upper limb deafferentation

Abstract Four monkeys were trained to perform wrist extension at regular intervals. The motor potential (MP) and EMG associated with these movements were recorded before, and in two of the animals, after dorsal rhizotomy extending from C2 to T4. Although wrist extension of the deafferented limbs appeared superficially normal, the contractions developed more slowly and were more prolonged. There was also a substantial increase in the interval between onset of cortical and muscular activity (corticomuscular delay), as well as increased variability of CMD. These changes could be attributed in part to reduced spinal excitability due to deafferentation. Despite the marked changes in timing, the configuration of the MP was unaltered. It is suggested that kinesthetic feedback is not registered in motor cortex during the performance of skilled movements.
Computer Vision-Based Video Interpretation Model for Automated Productivity Analysis of Construction Operations

Videotaping is an effective and inexpensive technique that has long been used in construction to conduct productivity analyzes. However, as schedules of modern construction projects become more and more compressed, the limitation of video-based analysis—intensive manual reviewing process—contrasts sharply with the need for effortless data analysis methods. This paper presents a study on developing a video interpretation model to interpret videos of construction operations automatically into productivity information. More specifically, this research formalizes key concepts and procedures of video interpretation within the construction domain. It focuses on designing a mechanism for furthering the crosstalk between the prior knowledge of construction operations and computer vision techniques. It uses this mechanism to guide the detection and tracking of project resources as well as work state classifications and abnormal production scenario identifications. The resulting approach has the potential to provide a common base for developing automated video interpretation procedures that can greatly improve current data collection and analyzes practices in construction. Experimental results from preliminary studies have shown the potential of the proposed video interpretation method as an improved productivity data analysis method.
Expression profile analysis of wild-type and fcc1 mutant strains of Fusarium verticillioides during fumonisin biosynthesis

Fusarium verticillioides produces a group of mycotoxins known as fumonisins that are associated with a variety of mycotoxicoses in humans and animals. In this study, DNA microarrays were constructed with expressed sequence tags (ESTs) from F. verticillioides. To identify genes with patterns of expression similar to the fumonisin biosynthetic (FUM) genes, the microarray was probed with labeled cDNAs originating from a wild-type strain and a fcc1 mutant grown on maize and in a defined medium adjusted to either pH 3 or pH 8. The comparative analyses revealed differential expression of genes corresponding to 116 ESTs when the fungal strains were grown on maize. Under different pH conditions, 166 ESTs were differentially expressed, and 19 ESTs were identified that displayed expression patterns similar to the FUM ESTs. These results provide candidate genes with potential roles in fumonisin biosynthesis.
QUENCHING OF INTRAMOLECULAR AMINE-HYDROCARBON EXCIPLEX FLUORESCENCE BY WATER

— The quenching of intramolecular exciplex fluorescence in 2,6-bis(methylamino)naphtha]ene, (II), 2,6-bis(/V-methyl, methylamino)naphthalene, (III) and 2,6-bis(N-dimethy], methylamino)naphthalene, (IV) by water was investigated. Exciplex fluorescence intensity decreased continuously with increase in water concentration; while monomer fluorescence intensity remained constant up to 25% of water, followed by a rapid increase in intensity. Absorption spectra showed that specific interaction occurred between water and ground state amine molecules at high concentrations (25% by volume) of water. These observations were interpreted in terms of a static quenching involving the interaction of water with the ground-state amine and a dynamic quenching involving the interactions of water with the exciplex. Our observations explain the greater efficiency of exciplex-fluorescence quenching by protic polar solvents.
Transient cerebral ischemia: pathophysiology.

Abstract The clinical features of TIAs in the anterior and posterior cerebral circulations are fairly uniform and usually easily recognized. The pathogenesis of TIAs is varied, complex, and incompletely understood. The importance of TIAs rests on the fact that they may serve as dramatic warnings of an impending stroke. Depending on the type and cause of a TIA, medical therapy, alone or in combination with surgical intervention, can postpone or sometimes prevent permanent neurologic deficit. It is the task of the clinician first to determine which among many mechanisms—vascular, cardiac hematologic, or circulatory—is responsible for transient neurologic symptoms in an individual patient, and then to supply appropriate therapy as prophylaxis against a stroke.
High Tc superconductors as doped Mott insulators: Fluctuating current and spin chirality

Abstract We find that a Gutzwiller projected d -wave BCS wavefunction exhibits current fluctuations which form a staggered pattern. This is a consequence of the projection and is expected on the basis of the SU(2) formulation of the t - J model. A spin chirality correlation is associated with the current correlation. We propose that these correlations characterize the pseudogap regime of underdoped cuprates
Sharp constants in the Paneyah–Logvinenko–Sereda theorem

Abstract We shall find some sharp constants in one type of uncertainty principle — Paneyah–Logvinenko–Sereda theorem.
Poster abstract: using adaptive range control to optimize 1-hop broadcast coverage in dense wireless networks

As technology trends continue to reduce the size, power consumption and cost of embedded networked sensors, they are rapidly approaching the small size and low cost necessary to allow a much wider range of novel usage. The resulting tremendous growth in sensor networks applications predicates increases in both scale and density for their wireless networks. Our initial measurements of an active tagging application, i.e., representing the state of everyday objects, within a common indoor environment shows that the average degree of such a network could easily range up to several hundred. In addition, the variance of object density is quite high, ranging by 2 orders of magnitude from 1 to over 100/m. The characteristics of future sensor networks large scale, high densities and large variances compounded with the fundamental broadcast nature of wireless networks poses a challenge for these systems: how to manage channel capacity to ensure good performance. Our work [2], in particular, considers the problem of how nodes within such dense networks can maximize the number of 1-hop receivers of a broadcast message, which we call the broadcast coverage problem. We choose broadcast coverage as a metric because broad classes of routing, localization and discovery protocols rely on periodic or aperiodic single hop broadcasts, and coverage is an important metric for such ∗This work was supported in part by NSF grant EIA-9986046 and DARPA contract N66001-00-1-8953.
Comparison of the post-embolization effects of tissue-plasminogen activator and simvastatin on neurological outcome in a clinically relevant rat model of acute ischemic stroke.

Abstract Data has emerged, largely from non-thromboembolic animal models of stroke, that suggests that statins, which have efficacy in preventing strokes when given pre-ischemically, may have a positive effect on stroke even when given post-ischemically, possibly through pleitropic cerebrovascular effects. The goal of this study was to characterize the effects of IV tPA in a clinically relevant model of stroke utilizing a vascular occlusion with a freshly formed clot, and evaluate the effects of post-ischemic administration of simvastatin on stroke outcome in this model. Neurological deficit, clot burden, and lesion volume were assessed after treatment with tPA in one experiment, and after treatment with simvastatin in another. In the tPA experiment, treatment with 10 mg/kg of tPA IV (with 20% given as an initial bolus, and 80% given as an infusion over the remaining 30 min), starting within an hour after stroke, resulted in significant reductions, compared with control animals, in neurological deficit (mean ± SD neuroscores of 21.5 ± 21.1 and 30 ± 29.3, respectively, p = 0.005), clot burden (p = 0.010) and lesion volume (p = 0.049) at 24 h. In the simvastatin experiment on the other hand, treatment with a 20 mg/kg of simvastatin as a single intraperitoneal dose within an hour after stroke resulted in no salutary effects on neurological deficit, clot burden or lesion volume compared with controls at 24 h. These results suggest that more research needs to be done to fully ascertain the therapeutic potential and optimal dosing paradigm of a post-ischemic treatment with a statin.
Effects of EP1 Receptor on Cerebral Blood Flow in the Middle Cerebral Artery Occlusion Model of Stroke in Mice

The lipid mediator prostaglandin E2 (PGE2) exhibits diverse biologic activity in a variety of tissues. Four PGE2 receptor subtypes (EP1−4) are involved in various physiologic and pathophysiologic conditions, but differ in tissue distribution, ligand-binding affinity, and coupling to intracellular signaling pathways. To characterize the role of the EP1 receptor, physiologic parameters (mean arterial blood pressure, pH, blood gases PaO2 and PaCO2, and body temperature), cerebral blood flow (CBF), and neuronal cell death were studied in a middle cerebral artery occlusion model of ischemic stroke in wild-type (WT) and EP1 knockout (EP1−/−) mice. The right middle cerebral artery was occluded for 60 min, and absolute CBF was measured by [14C] iodoantipyrine autoradiography. The effect of EP1 receptor on oxidative stress in neuronal cultures was investigated. Although no differences were observed in the physiologic parameters, CBF was significantly (P < 0.01) higher in EP1−/− mice than in WT mice, suggesting a role for this receptor in physiologic and pathophysiologic control of vascular tone. Similarly, neuronal cultures derived from EP1−/− mice were more resistant (90.6 ± 5.8% viability) to tert-butyl hydroperoxide-induced oxidative stress than neurons from WT mice (39.6 ± 17.2% viability). The EP1 receptor antagonist SC-51089 and calcium channel blocker verapamil each attenuated the neuronal cell death induced by PGE2. Thus, the prostanoid EP1 receptor plays a significant role in regulating CBF and neuronal cell death. These findings suggest that pharmacologic modulation of the EP1 receptor might be a means to improve CBF and neuronal survival during ischemic stroke.
Impact of knowledge regarding alternatives to settlement in dyadic negotiations: Whose knowledge counts?

Study I examined whose knowledge of a best alternative to the negotiated agreement (BATNA) produces documented benefits. The results suggest that (a)joint gain and the number of integrative trade-offs increase when the actor with the alternative is made aware of the alternative and (b) the actor with the alternative obtains a marginal increase in personal gain only when both negotiators (i.e., both the actor and the opponent) are aware of the actor's alternative. Study 2 explored changes in actor and opponent cognitions that result when each is informed about the actor's alternative. Results suggest that the existence of an attractive alternative changes actor and opponent walk away point ( often referred to as reservation point), perception of efficacy regarding negotiation skill, perceived value of the commodity being negotiated, and distribution of power.
Rumors of Identity: Gossip and Rapport in Ethnographic Research

For both practical and ethical reasons, ethnographers should convey to the people with whom they work a reasonably accurate notion of who they are and what they are doing (Richardson 1953:34). Although fieldworkers may choose from a variety of different strategies of observation and participation (Gold 1958; Hanna 1965). they have an obligation to represent themselves in a straightforward manner to those whose cooperation they seek (Barnes 1967:204; Jarvie 1969: 506) and this should be one of the first steps in the fieldwork process (Pelto and Pelto 1973:249). However, despite even the most conscientious efforts at explanation, people may not accept ethnographers' accounts of themselves at face value. The role of fieldworkers in the local community is always the mixed result of both their efforts to define it and the natives' interpretation of those efforts (Paul 1953:43 1; Wintrob 1969:69). Moreover, often the researcher's social identity undergoes periodic redefinition throughout the course of fieldwork as observer and observed learn more of each other and adjust their expectations accordingly (Janes 196 1). Given both the negotiative and the developmental nature of the ethnographer's status in the community, gossip concerning his or her identity and motives must be viewed as an almost inevitable feature of the fieldwork enterprise. When anthropologists describe inaccurate characterizations of their identity, they invariably portray them as inimical to developing the kind of rapport which is so vital to successful participant observation (e.g., Wax 1 957: 1 35ff.; Berreman 1962: 17; Agar 1980:58-6 1). If, following Freilich, rapport is defined as "a conditional agreement to communicate" (1970b:540), suspicions about the intentions of the anthropologist certainly may undermine its development in many circumstances (den Hollander 1967: 13). Yet, a rumor about the ethnographer's identity and intentions may also be a form of communication in its own right and its analysis can provide insight into both the culture being studied and the nature of participant observation. A series of rumors about my identity and motives emerged while I was studying a working class neighborhood in the city of Seville, Spain. In this paper I argue that these rumors can be best understood as symbolic markers of the progressive development of rapport and not as obstacles to its establishment. First, I will describe my efforts to explain my task and gain sufficient rapport with the residents of the neighborhood to allow for the collection of rich and reliable data. Then, I will describe the sequence of rumors that developed to account for my presence in Seville. Finally, I will offer an interpretation of the meaning of these rumors.
A general purpose subroutine for Fast Fourier Transform on a distributed memory parallel machine

One issue which is central in developing a general purpose Fast Fourier Transform (FFT) subroutine on a distributed memory parallel machine is the data distribution. It is possible that different users would like to use the FFT routine with different data distributions. Thus, there is a need to design FFT schemes on distributed memory parallel machines which can support a variety of data distributions. An FFT implementation on a distributed memory parallel machine which works for a number of data distributions commonly encountered in scientific applications is presented. The problem of rearranging the data after computing the FFT is also addressed. The performance of the implementation on a distributed memory parallel machine Intel iPSC/860 is evaluated.
ASSESSING STUDENTS' PERCEPTIONS OF THE INSTRUCTIONAL VALUE OF VISUAL ILLUSTRATIONS USED TO COMPLEMENT PROGRAMMED INSTRUCTION

Abstract This experiment was designed to evaluate (a) the effectiveness of eight types of visual illustrations used to complement programmed instruction when students, prior to receiving their instructional units, received specific instructions as to the types of information they were expected to obtain from their instruction; and (b) the validity of student perceptions regarding the instructional value of varied types of visual illustrations used to complement programmed instruction. 259 students at the Pennsylvania State University were randomly assigned to one of the nine treatment groups. Each student received a pre‐test, participated in his respective programmed presentation and received four individual criterial measures. The results of this study indicate that (a) all types of visuals are not equally effective in facilitating student achievement of different learning objectives; (b) the use of specific instructions to focus students’ attention on relevant learning cues in the more realistic illustr...
Spectrophotometric analysis of microleakage in the fine curved canals found in the mesial roots of mandibular molars.

Abstract Mesial roots from forty human mandibular first and second molar teeth were randomly assigned to two groups and obturated with laterally condensed gutta-percha or silver cones. Each group was divided into two subgroups. The first subgroup for each group consisted of specimens that had two canals with a common foramen. The second subgroup consisted of specimens with two canals and separate foramina. All specimens were obturated and exposed to 2 percent methylene blue dye at 37°C. for a period of 30 days. A dye-recovery, spectrophotometric method was used to evaluate the apical microleakage. Results indicated no statistically significant difference in leakage between the groups or subgroups.
Assessment of Gastric Ulceration and Gastrin Response in Horses with History of Crib-Biting

Abstract It was hypothesized that horses exhibiting crib-biting (CB) have a greater degree of gastric mucosal damage and higher serum gastrin response to concentrate feeding than non-crib-biting (NCB) horses. Eighteen mature horses, 9 CB and 9 NCB, were used to determine prevalence and severity of gastric mucosal damage and effect of concentrate feeding on circulating gastrin. Horses were maintained on pasture with free access to hay and fed a pelleted concentrate diet twice daily. Number of crib-bites and duration of cribbing bouts were recorded in a 24-hour period. Endoscopic examinations (EE) of the squamous mucosa were performed and gastric fluid sampled after 24 to 28 hour feed removal. Following EE, horses were returned to pasture for 72 hours. Blood was collected following 12-hour feed removal (0 minutes), and at 60 and 120 minutes after consuming 1 kg of concentrate. Mean number of crib bites in 24 hours was 1,558 ± 303 with CB peaking prior to and during the afternoon feeding (3:30 PM, P P P
Probing Cardiac Membrane Proteins with Fluorescence Resonance Energy Transfer

We have used time-resolved fluorescence resonance energy transfer (TR-FRET) to study the structural basis of regulation of sarcoplasmic reticulum Ca2+ ATPase (SERCA) by a single-pass transmembrane protein, phospholamban (PLB). The most prominent feature of heart failure is calcium mishandling, which is largely due to impaired activity of sarcoplasmic reticulum calcium ATPase (SERCA), which actively transports Ca2+ from cytosol into the SR to relax the muscle. Unphosphorylated phospholamban inhibits SERCA by decreasing its apparent Ca2+ affinity. This inhibition can be relieved by either micromolar Ca2+ or by phosphorylation of PLB. The structural basis for relief of inhibition remains controversial. Cross-linking studies support the canonical dissociation model. However, recent EPR, NMR and FRET studies support the subunit model, in which subtle structural rearrangements are required to relieve the inhibition. The goal of this study is to elucidate the structural rearrangements during relief of inhibition. Previous EPR and NMR studies found that the cytoplasmic domain of PLB exists in a dynamic equilibrium between T and R states. We have used time-resolved fluorescence resonance energy transfer (TR-FRET) to probe the complex directly by measuring the distances between SERCA (C674) and a series of positions on PLB in co-reconstituted vesicles. We found that the distances between SERCA and the cytoplasmic domain of PLB are best fitted with two Gaussian distance distributions, suggesting that the cytoplasmic domain of bound PLB exists in two states. Results will be reported on the effects of perturbations in this system which are known to relieve inhibition, including PLB phosphorylation, PLB mutation, and calcium binding to SERCA. We conclude that the function of the SERCA-PLB complex depends primarily on the structural equilibrium between two principal structural states of the complex.
Cost Control after the ACA

This Perspective explains why implementation analysis of the cost control provisions within the Patient Protection and Affordable Care Act is not particularly useful. These provisions are either relatively straightforward or, more commonly, so flawed that successful implementation is highly unlikely. The analysis shows that effective and equitable cost control will require coordinating payers to create all-payer fee setting. This poses significant challenges but has been implemented relatively successfully in many countries. The balance of the article uses experience with all-payer systems in other countries and fee setting within Medicare to identify key choices within any all-payer system. It highlights the importance of simplifying considerations and focusing on outcomes—the incomes of providers and total spending—rather than engaging in a hopeless search for technocratic payment “accuracy.”
Neuro-oncology: An Overview

The direct, indirect, and treatment-related effects of cancer on the nervous system have received variable attention by neurologists over the past century. The diseases encompassed in the neuro-oncology field and our understanding of them have increased rapidly during the past 30 years. In part, progress has been driven by technological achievements in neuroimaging, in particular, computed tomography and magnetic resonance imaging. These advances have allowed unprecedented opportunities to view the anatomy and pathology of the central nervous system (CNS) and, to an extent, portions of the peripheral nervous system that could be affected by cancer or its treatment. Clear gains have occurred in diagnostic accuracy, neurosurgical safety, ease of tumor resection, and safer and more accurate radiotherapy. After carmustine chemotherapy was introduced in the late 1960s, neurosurgeons and a new breed of physician, the neuro-oncologist, investigated the clinical benefits of an increasing number of anticancer agents against gliomas, medulloblastomas, and metastatic tumors in the CNS. In parallel, another sector of neuro-oncology developed that was more closely allied with neurology. The focus of this activity was in correlative neurology and pain management issues.
Step-height metrology for data storage applications

The measurement of bump heights and pit depth on compact discs (CD) with atomic force microscopes (AFMs) is quite different from the measurement of step heights on step height calibration standards. Both the bumps and the pits show much larger transition regimes and more structural irregularities. The irregularities disqualify the effective use of profile based algorithms, which minimize the influence of any remaining motion deviations of the scan apparatus, to determine the height. Therefore a histogram height algorithm has to be used. The results of the bump height and pit depth measurements varied about 20 nm over the different sample regions. The remaining approximately 30 nm difference between the average of the bump height and pit depth is believed to result from the sample preparation procedure. By itself, the large sample variation observed will result in rather large measurement uncertainties for the measurement of the average height and depth of these features, if the averaging does not include a large amount of data taken at many different sample positions.
Compressed Sensing MRI

This article reviews the requirements for successful compressed sensing (CS), describes their natural fit to MRI, and gives examples of four interesting applications of CS in MRI. The authors emphasize on an intuitive understanding of CS by describing the CS reconstruction as a process of interference cancellation. There is also an emphasis on the understanding of the driving factors in applications, including limitations imposed by MRI hardware, by the characteristics of different types of images, and by clinical concerns.
Effect of momentary stress on brain energy metabolism in weanling mice: Apparent use of lactate as cerebral metabolic fuel concomitant with a decrease in brain glucose utilization

The hypothesis that the anxiety induced by repeated injections affects brain energy metabolism was tested. Normal 19- to 21-day-old mice were stressed by two sham intraperitoneal injections within 4 min, at which time they were decapitated. Noninjected, control littermates were quickly decapitated. Momentary stress increased plasma glucose (12%), glycerol (85%), β-hydroxybutyrate (108%), and lactate (153%)—a reflection of elevated plasma cortisol (25%) and glucagon (45%). In brain, stress increased levels of glucose-6-P (15%) and fructose-6-P (17%). The brain pyruvate concentration increased 74%; lactate 76%. Citrate, α-ketoglutarate, and malate increased 15, 95, and 37%, respectively. Levels of glycogen, glucose, phosphocreatine, ATP, ADP, and AMP were unchanged. The brain lactate/ pyruvate ratio was normal but the brain/plasma lactate ratio fell 32%. Metabolite changes in the stressed animals were compatible with a decrease in the glycolytic flux at the phosphofructokinase step and a paradoxical increased flux in the Krebs citric acid cycle. The decreased brain/plasma lactate ratio supported increased uptake of lactate from plasma and increased brain lactate oxidation. Metabolite changes similar to those described above occurred in unstressed mice injected with lactate. Findings confirm a positive effect of stress on brain metabolism, support a role for lactate as an oxidative fuel for brain, and caution that the rate of cerebral glucose utilization may not always reflect brain energy (oxidative) metabolism accurately.
Upregulation of Oct-4 isoforms in pulmonary artery smooth muscle cells from patients with pulmonary arterial hypertension

Oct-4 is a transcription factor considered to be one of the defining pluripotency markers in embryonic stem cells. Its expression has also been demonstrated in adult stem cells, tumorigenic cells, and, most recently and controversially, in somatic cells. Oct-4 pseudogenes also contribute to carcinogenesis. Oct-4 may be involved in the excessive proliferation of pulmonary arterial smooth muscle cells (PASMC) in patients with idiopathic pulmonary arterial hypertension (IPAH), contributing to the pathogenesis of IPAH. In this study, we show that Oct-4 isoforms are upregulated in IPAH-PASMC. Human embryonic stem cells (H9 line) and human PASMC from normotensive subjects were used throughout the investigation as positive and negative controls. In addition to significant upregulation of Oct-4 in a population of IPAH-PASMC, HIF-2α, a hypoxia-inducible transcription factor that has been shown to bind to the Oct-4 promoter and induces its expression and transcriptional activity, was also increased. Interestingly, a substantial upregulation of Oct-4 isoforms and HIF-2α was also observed in normal PASMC exposed to chronic hypoxia. In conclusion, the data suggest that both Oct-4 isoforms are upregulated and potentially have a significant role in the development of vascular abnormalities associated with the pathogenesis of IPAH and in pulmonary hypertension triggered by chronic hypoxia.
Automated electric valve for electrokinetic separation in a networked microfluidic chip.

This paper describes an automated electric valve system designed to reduce dispersion and sample loss into a side channel when an electrokinetically mobilized concentration zone passes a T-junction in a networked microfluidic chip. One way to reduce dispersion is to control current streamlines since charged species are driven along them in the absence of electroosmotic flow. Computer simulations demonstrate that dispersion and sample loss can be reduced by applying a constant additional electric field in the side channel to straighten current streamlines in linear electrokinetic flow (zone electrophoresis). This additional electric field was provided by a pair of platinum microelectrodes integrated into the chip in the vicinity of the T-junction. Both simulations and experiments of this electric valve with constant valve voltages were shown to provide unsatisfactory valve performance during nonlinear electrophoresis (isotachophoresis). On the basis of these results, however, an automated electric valve sy...
TNF-dependent upregulation of hcmv major immediate early promoter (MIEP) during warm ischemia-reperfusion

Abstract Reactivation of latent Human Cytomegalovirus (HCMV) results in morbidity and mortality in immunosuppressed patients. We have previously demonstrated that TNF plays a major role in inducing Immediate Early (IE) gene expression both as a result of soluble TNF and allotransplantation. The major immediate-early promoter (MIEP) of HCMV controls the expression of IE genes. Transgenic mice containing the lacZ gene regulated by the HCMV MIEP are ideal for analysis of factors that regulate promoter activity, and hence the reactivation process. TNF is known to play a role in warm ischemia-reperfusion injury. We thus sought to determine whether warm ischemia-reperfusion injury could induce upregulation of HCMV MIEP in vivo, and the role of TNF in this process. Methods: 45 minute renal warm ischemia-reperfusion was performed in the left kidney while the right served as control. MIEP-lacZ transgenic mice were divided into 2 groups. Group I (n = 6): Ischemia + 24-hr reperfusion; Group II (n = 3): Sham controls. Group III consisted of transgenic TNF type I & II receptor Knockout (KO) mice (n = 4). Kidneys were harvested at 24 hrs reperfusion. Quantitative β-Galactosidase activity per nanogram of protein in tissues was done in triplicate. Fold-induction was determined by ratio of ischemia-reperfused kidney to its control. Histological analysis was performed by H&E, and staining for CD4, CD8 and MAC-1. RT-PCR was done for TNF, IL-1 and IFN-γ. Statistical analysis was done by means of student t-test for independent samples. Results: Warm ischemia-reperfusion induces a significant induction of transgene expression in kidneys (14.96 ± 6.51), as compared to sham surgical controls (1.48 ± 0.44) [p
The evolutionary advantages of sexual dimorphism.

Abstract The evolutionary advantages of sexual dimorphism were theoretically investigated, using Volterra-like competition equations. A sufficient condition for the persistence of a dioecious species is an ecological partitioning of the habitat along sexual lines. If such specialization insures that the dioecious species is ecologically more efficient than its monoecious progenitor, then the dioecious type will prevail. Considerable ecological specialization is required to overcome an initial reproductive disadvantage, but, with the requisite specialization, a permanent reproductive deficit can be supported.
Elevation in serum lactate at the time of febrile neutropenia (FN) in hemodynamically-stable patients with hematologic malignancies (HM) is associated with the development of septic shock within 48 hours.

Background: Hospitalized patients who develop febrile neutropenia (FN) are treated empirically with antibiotics due to a high risk of developing septic shock. Currently, there is no method to predict which patients are at greatest risk. This study was designed to determine whether serum lactate, measured at the time of FN, is associated with the development of septic shock in hospitalized hematologic malignancy (HM) patients. Methods: Vital signs and lactate were measured during episodes of FN. The primary endpoint was the development of septic shock. Using a prospective, nested, case-control design, controls were matched on length of stay at the time of septic shock to achieve 80% power to detect an OR of ≥ 2.5. Using logistic regression, we evaluated the association of vital signs and lactate with the subsequent development of septic shock. Results: Of the 547 patients enrolled, 46 (8.4%; 95% CI 6.2-10.9) developed septic shock. Baseline characteristics were similar between the groups. In univariate an...
Evaluation and prognostication in coma

Electroencephalography (EEG) and evoked potential (EP) studies are neurophysiologic techniques which provide information on physiological state and response to therapy, and may aid diagnosis and prognosis. Serial studies or continuous monitoring may enable changes to be detected prior to irreversible deterioration in the patient's condition. Current computer technology allows simultaneous display and correlation of electrophysiologic parameters, cardiovascular state and ICP. Continuous EEG monitoring in the ICU has been shown to have a decisive or contributing impact on medical decision making in more than three-quarters of patients. In addition, continuous EEG monitoring has revealed previously unsuspected non-convulsive seizures in two-thirds of patients. Somatosensory and auditory EPs can provide useful prognostic information in coma patients, however, these tests are etiologically non-specific and must be carefully integrated into the clinical situation. Motor EPs offer a potentially useful tool for evaluating motor system abnormalities in the ICU. Thus, neurophysiologic tests are established monitoring tools in the neurological intensive care unit.
Misperception Among Gay Men of the Risk for AIDS Associated with Their Sexual Behavior1

Until a vaccine against AIDS is developed, the most effective strategy for preventing the spread of the disease among gay men, the largest risk group, is to persuade them to abstain from particular kinds of sexual practices implicated in the transmission of the AIDS virus. Motivation to comply with risk-reduction guidelines, however, is dependent in part on a realistic appraisal of the degree of risk associated with one's sexual practices. Data are presented from 160 asymptomatic gay men. Their subjective assessment of the riskiness of their sexual behavior is compared to an objective assessment of the riskiness of their sexual practices. Factors associated with a tendency to underestimate the riskiness of one's practices are examined. Finally, the implications of the findings for public health education efforts among gay men are discussed.
Mobility of the mandible following advancement and maxillomandibular or rigid internal fixation: an experimental investigation in Macaca mulatta.

Abstract This study examined the postsurgical range of mandibular motion following sagittal advancement osteotomy in Macaca mulatta when either maxillomandibular or rigid ossesous fixation were used. Seventeen adult female Macaca mulatta underwent sagittal advancement osteotomy of approximately 4 to 6 mm. Six had 6 weeks of maxillomandibular fixation and eleven had rigid osseous fixation with no maxillomandibular fixation. Mandibular range of motion was measured by the change in the angle of the posterior aspect of the mandibular ramus from a closed-mouth and an open-mouth cephalogram. Parametric tests were used to statistically analyze the results. The results of this investigation showed that the animals who did not undergo maxillomandibular fixation maintained a greater range of motion in the early postsurgical period and obtained preoperative mobility by 12 weeks postsurgery. The animals who underwent six weeks of maxillomandibular fixation showed statistically significant decreases in range of motion when compared to the rigid fixation group at each period of time postsurgery, with significant reductions from preoperative values at 12 weeks postsurgery.
Example based generation of custom data analysis appliances

Custom interfaces, which we call appliances, allow users to efficiently carry out specialized tasks. Without one, a user is often required to perform repetitive mechanical steps using general purpose interfaces, which we call tools. Much research has attempted to enable non-programmers to create appliances for themselves.We present a system in which a user can choose an example of the task behavior to be automated from a visualization of his past operations. The example is transformed into a visual language, using two simple rules to generalize from the single example to a class of tasks. The user can then edit this representation directly, or continue to refine the example using selective undo and redo. The visual representation can be transformed into an esthetically pleasing appliance by deleting irrelevant components, and rearranging, resizing, and relabeling other components. Restricting the domain to data analysis tasks enables a well-matched visual query language to be used. Appliance interactions are automatically provided by the underlying interactive visualization system in which the appliance is embedded.An observational study suggests that this system represents a useful point on the ease-of-use vs. expressive power tradeoff appropriate for data analysis, and that the ability to choose and modify examples after the fact is helpful.
Nutritional Issues in Peritoneal Dialysis Patients: How Do They Differ From That of Patients Undergoing Hemodialysis?

It is important to understand the unique aspects vis-a-vis protein-energy wasting for patients undergoing PD. As a result of obligatory protein losses with the therapy, the serum albumin levels of patients undergoing PD are lower, as is the threshold serum albumin at which the risk for death is increased. Consequently, it is prudent to consider a lower threshold for serum albumin for the diagnosis of protein-energy wasting for patients undergoing PD. Likewise, it is important to consider the energy intake from obligatory nutrient absorption in the form of carbohydrates when estimating total energy intake (diet and dialysate) when evaluating patients for protein-energy wasting. The continuous nature of PD also has important therapeutic implications for protein-energy wasting. Such patients are more likely to have a complete correction of metabolic acidosis, and glucose absorption from the peritoneal dialysate has a protein-sparing effect, allowing some patients to maintain neutral nitrogen balances in the face of suboptimal protein intake. In contrast, clinical trials of amino-acid-based PD solutions have not met expectations and cannot be recommended for routine use for treatment of protein-energy wasting. In conclusion, it is important to consider these unique nutritional considerations when providing care to patients undergoing PD.
Two Stacks in Series: A Decreasing Stack Followed by an Increasing Stack

We study a sorting machine consisting of two stacks in series where the first stack has the added restriction such that entries in the stack must be in decreasing order from top to bottom. We give the basis of the class of permutations that are sortable by this machine which shows that it is enumerated by the Schroder numbers.
Characteristics of D-glucosamine uptake by rat brain synaptosomes.

— The uptake of D-glucosamine by rat brain synaptosomes is studied as a function of time, temperature and synaptosomal protein and substrate concentrations. The rate of D-glucosamine uptake, after correcting for simple diffusion, obeys Michaelis-Menten kinetics. The apparent kinetic constants for the uptake process are Km= 2.5 0.8 mm, Vmax= 3.7 ± 1.2 nmol/mg protein/min. D-Glucose, D-mannose, 2-deoxy-D-glucose and 3-0-methyl-o-glucose are potent inhibitors of D-glucosamine uptake. 2-Deoxy-D-glucose and D-glucosamine inhibit the uptake of one another in a simple competitive manner, indicating their sharing of a common transport system. Cytochalasin B, phloretin and phloridzin are powerful competitive inhibitors of D-glucosamine uptake with apparent inhibitor constants (K1) of 7.0 × 10-5, 2.3 × 10-3 and 0.4 mM, respectively. The uptake is unaffected by Na+, Li+ and Mg2+, partially inhibited by NH4+, Mn2+ and Ca2+, and slightly stimulated by PO4-ions. D-Glucosamine uptake is also sensitive to inhibition by several sulfhydryl reagents, thus implying the involvement of sulfhydryl groups in the transport process. The apparent affinity constants for synaptosomal transport for both D-glucosamine and 2-deoxy-D-glucose are about 4 times greater in 7-day-old than in the adult rat brains.