cssi/SciSciGPT-SciSciNet huggingface dataset:
Open Urologic Procedures: Radical Cystectomy with Diversion, Radical Prostatectomy, and Radical Nephrectomy Anesthetic Considerations

While recent advances in technology and training have allowed for increasing use of laparoscopic and robotic techniques in common urologic surgery, the open approach remains relevant in the context of complex urologic surgery performed for malignant disease.
Pre-existing distortions in nucleic acid structure aid polypurine tract selection by HIV-1 reverse transcriptase.

Abstract Precise cleavage at the polypurine tract (PPT)/U3 junction by human immunodeficiency virus type 1 (HIV-1) reverse transcriptase RNase H is critical for generating a correct viral DNA end for subsequent integration. Using potassium permanganate (KMnO4) modification, we have identified a significant distortion in the nucleic acid structure at the HIV-1 PPT/U3 junction in the absence of trans-acting factors. Unusually high reactivity of template thymine +1 is detected when the PPT primer is extended by DNA or RNA at its 3′ terminus. Chemical footprinting suggests that the extent of base unstacking in the wild-type species is comparable when the +1 A:T base pair is replaced by a C:T mismatch. However, reactivity of this template base is diminished after alterations to upstream (rA)4:(dT)4 or (rG)6:(dC)6 tracts. Importantly, there is a correlation between the structural deformation at base pair +1 and precise cleavage at the PPT/U3 junction by HIV-1 reverse transcriptase/RNase H. KMnO4 modification also revealed unusually high reactivity for one of two (dT)4:(rA)4 duplexes upstream of the PPT/U3 junction, suggesting a significant structural distortion within the PPT itself in the absence of the retroviral polymerase. Structural abnormalities in this region are not only essential for resistance of the PPT to hydrolysis but also significantly impact the conformation of the PPT/U3 junction. Our data collectively suggest that the entire PPT sequence contributes to the structural distortion at the PPT/U3 junction, potentially providing a mechanism for its selective processing.
Gangliocytic paraganglioma, a rare cause of upper gastrointestinal bleeding: Endoscopic ultrasound findings presented

Gangliocytic paraganglioma (GP) is an uncommon benign neurogenic tumor of the digestive tract that is usually located in the descending duodenum. Patients with GP usually present with upper gastrointestinal hemorrhage, which reflects the tendency of the tumor to ulcerate the mucosa. The authors report a patient in whom the tumor was overlooked on routine radiologic examinations and initial endoscopy. It was discovered in the distal transverse duodenum at small bowel enteroscopy. The findings of endoscopic ultrasonography are correlated with radiographic and histologic examination. 10 refs.
Schlieren photography in physics

Schlieren photography has been used many years in physics; however it has proved to be exceptionally valuable in the study of ultrasonic waves in liquids. Part of the reason for its value is that many of the ultrasonic phenomena studied have their optical analogies. Thus, when one studies ultrasonic images the actually is studying a general wave phenomena from a perspective that is impossible with light alone. Examples are given of ultrasonic schlieren photographs as are conclusions possible from their study.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
The evolving role of microRNAs in animal gene expression.

MicroRNAs (miRNAs) constitute an abundant family of 22-nucleotide RNAs that base-pair to target mRNAs and typically inhibit their expression. To assess the global impact of animal miRNAs on gene regulation, the expression of predicted targets and their cognate miRNAs was extensively analyzed in mammals and Drosophila.1,2 In general, targets are co-expressed at relatively low or undetectable levels in the same tissues as the miRNAs predicted to regulate them. Additionally, genes that are highly co-expressed with miRNAs usually lack target sites. The authors conclude that many animal genes are under evolutionary pressure to maintain or avoid complementary sites to miRNAs.1,2 Thus, the miRNA pathway broadly contributes to the complex gene regulatory networks that shape animal tissue development and identity. BioEssays 28: 449–452, 2006. © 2006 Wiley Periodicals, Inc.
Intensivist-to-Bed Ratio: Association With Outcomes in the Medical ICU

Objective With an increasing number of critical care beds, a shortage of critical care physicians, and pressure from purchasers, there is a need to define the optimal intensivist-to-ICU bed ratio. The objective of this study was to determine if there are any associations between the intensivist-to-ICU bed ratio and the outcome of patients admitted to the medical ICU Design Retrospective cohort study Setting A tertiary care medical center Patients All critically ill patients admitted to a medical ICU between December 8, 2001, and July 14, 2003 Interventions None Measurements Demographics, APACHE (acute physiology and chronic health evaluation) III-predicted mortality, ICU length of stay (LOS), hospital LOS, and ICU and hospital mortality rates. Four time periods based on intensivist-to-ICU bed ratios of 1:7.5, 1:9.5, 1:12, and 1:15 were identified. Regression analyses were performed to develop customized models to predict ICU and hospital LOS and mortality. The ICU LOS ratio, defined as the ratio of the observed to predicted LOS, and standardized mortality ratio (SMR) were calculated for each of the four periods Results A total of 2,492 patients were included in the study. There was no difference in the severity of illness at the time of ICU admission among the four periods. The mean ICU LOS ratio was longer for an intensivist-to-ICU bed ratio of 1:15 compared to the other periods. The ICU and hospital SMR did not differ significantly among the four periods Conclusion Differences in intensivist-to-ICU bed ratios, ranging from 1:7.5 to 1:15, were not associated with differences in ICU or hospital mortality. However, a ratio of 1:15 was associated with increased ICU LOS
Thin-silica-diaphragm-based fiber optic acoustic sensors

In this sensor, we demonstrate the developing and testing of fiber optic sensors intended to detect acoustic waves. The sensor is based on a novel design housing a thin silica diaphragm and a single mode fiber in an extrinsic Fabry- Perot interferometric structure. The designed sensor is tested for different applications including the detection of the partial discharges inside a power transformer. The test results indicate that the designed sensor can detect acoustic signals with high sensitivity at frequency as high as 200 kHz.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Mt-Hsp70 homolog, Ssc2p, required for maturation of yeast frataxin and mitochondrial iron homeostasis

Here we show that the yeast mitochondrial chaperone Ssc2p, a homolog of mt-Hsp70, plays a critical role in mitochondrial iron homeostasis. Yeast withssc2-1 mutations were identified by a screen for altered iron-dependent gene regulation and mitochondrial dysfunction. These mutants exhibit increased cellular iron uptake, and the iron accumulates exclusively within mitochondria. Yfh1p is homologous to frataxin, the human protein implicated in the neurodegenerative disease, Friedreich's ataxia. Like mutants ofyfh1, ssc2-1 mutants accumulate vast quantities of iron in mitochondria. Furthermore, using import studies with isolated mitochondria, we demonstrate a specific role for Ssc2p in the maturation of Yfh1p within this organelle. This function for a mitochondrial Hsp70 chaperone is likely to be conserved, implying that a human homolog of Ssc2p may be involved in iron homeostasis and in neurodegenerative disease.
Compatibilizers for thermotropic liquid crystalline polymer/polyolefin blends prepared by reactive mixing : The effect of processing conditions

The effect of processing conditions on the melt formation of a graft-copolymer compatibilizer for blends of a thermotropic liquid crystalline polymer (TLCP) and polyolefins was investigated. The compatibilizer was formed by a melt acidolysis reaction of a 50/50 (w/w) blend of TLCP and the sodium salt of a poly(ethylene-coacrylic acid) ionomer. The effects of various processing conditions in a batch mixer and a single-screw extruder on the extent of reaction were assessed. The extent of graft-copolymer formation and the efficacy of the product as a compatibilizer for TLCP/polyethylene blends were affected by the processing temperature and the screw (or rotor) speed.
Short communication: Kelp taste preferences by dairy calves

Kelp is a common feed additive used on many dairy farms in the United States. However, few data are available supporting the efficacy of its addition to cattle feed. The purpose of this study was to evaluate the taste preferences of calves provided with 0, 30, or 60 g of kelp daily in a sequential elimination experiment. Calves in this study always ranked the control treatment first when given a choice and consumed 34.5% more dry matter from the control treatment in the first 3-d segment of the experiment. During the second feeding segment (d 4 and 5), when the control treatment was removed, daily dry matter consumption was reduced in 4 out of 6 calves compared with control calves when this treatment was available (first feeding segment). However, calves did not differentiate between the 2 amounts of kelp. Results indicated that calves preferred calf starter grains without kelp.
Treatment of lumbar spinal stenosis: a balancing act

COMMENTARY ON: Chen E, Tong KB, Laouri M. Surgical treatment patterns among Medicare beneficiaries newly diagnosed with lumbar spinal stenosis. Spine J 2010;10:588–594 ( in this issue ).
To Consult or Not to Consult: The Role of the Endocrinologist in the Management of Diabetes Mellitus in the Hospital Setting

Hyperglycemia in the hospitalized patient presents unique and frequent dilemma for the health care provider. The complications of hyperglycemia, whether due to diabetes mellitus or acute illnesses can have serious clinical and financial implication during hospitalization. What is the role of the endocrinologist in the hospitalized hyperglycemic patient? Does the endocrine consult in and of itself improve clinical and financial outcome, or is it the level of subject matter expertise of the clinicians that are treating the patient the more important factor in improving the quality outcomes?
Illuminating microRNA Transcription from the Epigenome

Cellular gene expression is governed by a complex, multi-faceted network of regulatory interactions. In the last decade, microRNAs (miRNAs) have emerged as critical components of this network. miRNAs are small, non-coding RNA molecules that serve as post-transcriptional regulators of gene expression. Although there has been substantive progress in our understanding of miRNA-mediated gene regulation, the mechanisms that control the expression of the miRNAs themselves are less well understood. Identifying the factors that control miRNA expression will be critical for further characterizing miRNA function in normal physiology and pathobiology. We describe recent progress in the efforts to map genomic regions that control miRNA transcription (such as promoters). In particular, we highlight the utility of large-scale “-omic” data, such as those made available by the ENCODE and the NIH Roadmap Epigenomics consortiums, for the discovery of transcriptional control elements that govern miRNA expression. Finally, we discuss how integrative analysis of complementary genetic datasets, such as the NHGRI Genome Wide Association Studies Catalog, can predict novel roles for transcriptional mis-regulation of miRNAs in complex disease etiology.
Two-Dimensional Streptavidin Crystals on Giant Lipid Bilayer Vesicles

Streptavidin was crystallized on giant bilayer vesicles (20−60 μm) in sucrose solution at various pH values. The streptavidin-coated vesicles exhibited unique roughened spherical and prolate ellipsoidal shapes, illustrating resistance to curvature of the two-dimensional crystals. Studies indicated that the spheroids and prolate ellipsoids correspond to different crystal morphologies. Through confocal microscopy, the various crystal morphologies on vesicle surfaces were observed under different solution conditions. Unlike two-dimensional (2D) streptavidin crystals grown in ionic buffer that assume the P1, P2, and C222 lattices at pH 4, 5.5, and 7, respectively (Wang et al. Langmuir 1999, 15, 1541), crystals grown in sucrose with no added salt show only the lowest density C222 lattice due to strong electrostatic interactions.
Compiler Analysis of the Value Ranges for Variables

Programs can be analyzed to determine bounds on the ranges of values assumed by variables at various points in the program. This range information can then be used to eliminate redundant tests, verify correct operation, choose data representations, select code to be generated, and provide diagnostic information. Sophisticated analyses involving the proofs of complex assertions are sometimes required to derive accurate range information for the purpose of proving programs correct. The performance of such algorithms may be unacceptable for the routine analysis required during the compilation process. This paper presents a discussion of mechanical range analysis employing techniques practical for use in a compiler. This analysis can also serve as a useful adjunct to the more sophisticated techniques required for program proving.
Effects of drug-induced changes in brain monoamines on aggression and motor behavior in mice

Abstract Mice maintained on a basal casein diet supplemented with 4% L-tyrosine potentiated L-DOPA effects on aggression. At low doses (12.5–25 mg/kg) L-DOPA increased aggression whereas at high doses (50–100 mg/kg) it decreased aggression. 5-HTP (50–200 mg/kg) produced a dose-dependent decrease in aggression and motor activity which was antagonized by pretreatment with dietary L-tyrosine (4%) or L-DOPA (50 mg/kg). L-DOPA induced reductions in motor activity were, in turn, antagonized by 5-HTP. Increases in motor activity following d-amphetamine (3 mg/kg) were sharply reduced by 5-HTP (50–100 mg/kg), but 5-HTP potentiated reductions in aggression following d-amphetamine. The concentration in brain of tyrosine, DOPA, dopamine (DA), noradrenaline (NA), DOPAC, HVA, tryptophan, serotonin (5-HT), and 5-HIAA were obtained following drug and diet treatments. The changes observed, particularly in DA and 5-HT metabolites, provide further evidence for an inhibitory role of brain 5-HT systems in the mediation of the behavioral effects of d-amphetamine and the catecholamine precursors, L-tyrosine and L-DOPA.
Opioid-Induced GABA Potentiation after Chronic Morphine Attenuates the Rewarding Effects of Opioids in the Ventral Tegmental Area

GABA transmission in the ventral tegmental area (VTA) is critical for fine tuning the activity of dopamine neurons in response to opioids. However, the precise mechanism by which GABA input shapes opioid reward is poorly understood. We observed a reduction of conditioned place preference for low doses of the opioid [d-Ala2, N-MePhe4, Gly5-ol]-enkephalin (DAMGO) and a switch in the functional effects of μ-opioid receptor modulation of GABA postsynaptic currents in the mouse VTA 1 d after chronic morphine treatment. Specifically, whereas in naive mice DAMGO inhibits GABA postsynaptic currents, GABAergic currents are potentiated by DAMGO after chronic morphine treatment. Importantly, pretreatment with the cAMP signaling inhibitor (R)-adenosine, cyclic 3',5'-(hydrogenphosphorothioate) triethylammonium both restored DAMGO reward and reversed the DAMGO-mediated potentiation, thereby reestablishing the inhibitory effects of opioids on GABA currents. Thus, a paradoxical bidirectionality in μ-receptor-mediated control of GABA transmission following chronic morphine treatment is a critical mechanism that determines the expression of opioid reward in the VTA.
Synthesis and Electronic Properties of Regioisomerically Pure Oxochlorins

We describe a two-step conversion of C-alkylated zinc chlorins to zinc oxochlorins wherein the keto group is located in the reduced ring (17-position) of the macrocycle. The transformation proceeds by hydroxylation upon exposure to alumina followed by dehydrogenation with DDQ. The reactions are compatible with ethyne, iodo, ester, trimethylsilyl, and pentafluorophenyl groups. A route to a spirohexyl-substituted chlorin/oxochlorin has also been developed. Representative chlorins and oxochlorins were characterized by static and time-resolved absorption spectroscopy and fluorescence spectroscopy, resonance Raman spectroscopy, and electrochemistry. The fluorescence quantum yields of the zinc oxochlorins (Φf = 0.030−0.047) or free base (Fb) oxochlorins (Φf = 0.13−0.16) are comparable to those of zinc tetraphenylporphyrin (ZnTPP) or free base tetraphenylporphyrin (FbTPP), respectively. The excited-state lifetimes of the zinc oxochlorins (τ = 0.5−0.7 ns) are on average 4-fold lower than that of ZnTPP, and the li...
Spectrophotometric studies on the platinum(IV)-prochlorperazine bismethanesulfonate complex

We have studied the formation of a platinum complex and developed a simple, rapid and sensitive spectrophotometric method for the determination of platinum in solution. The method is based on the complexation reaction of the chromogen, prochlorperazine bismethane-sulfonate (PCPMS), with platinum(IV) in phosphoric acid medium which forms a reddish brown 1 ∶ 1 complex with an absorption maximum around 528 nm. The reaction is fast in the presence of copper(II) and goes to completion within 1 min. Beer's law is obeyed over the concentration range 0.3–7.2 μg/ml of platinum(IV) with an optimal range of 1.2–6.6 μg/ml. The molar absorptivity is 2.65 × 1041 mol−1 cm−1 and the Sandell's sensitivity is 7.8 ng cm−2. The stability constant, logK, of the complex is 4.96±0.1 at 25 ° C. The effects of time, temperature, concentrations of acids, PCPMS and copper(II), and the interference by various ions are investigated. The method has been successfully applied to the determination of platinum content in alloys and minerals.
A Real-Time Conductor Sag Measurement System Using a Differential GPS

A real-time and “direct” method of measuring the absolute value of sag on a transmission-line conductor using a differential global positioning system (DGPS) is presented. The method includes a real-time data-processing module integrated into the DGPS system. The GPS signals corresponding to physical movement of the midspan of a transmission-line conductor were obtained so that conductor-to-ground clearance could be recorded in real time. Several field tests were designed and implemented to test the DGPS method under varying conditions of the transmission-line current. A comparison of results obtained from the DGPS method with those from a laser-range finder indicates an accuracy of 1 in.
Overview of fatigue behavior in copper single crystals—I. Surface morphology and stage I crack initiation sites for tests at constant strain amplitude

Abstract The sharp-corner technique coupled with scanning electron microscopy has been used here for observing morphological changes at the surfaces of fatigued copper monocrystals. This technique confirms a number of recently-reported observations on persistent slip band (PSB) and crack initiation behavior, but elaborates others and provides new insights. For example, it reveals PSB encroachments (i.e. negative protrusions) which indicate that one mechanism of protrusion propagation is a shuttling mechanism amongs PSB-matrix lamellae. It is also found that there is a tendency to form longer cracks preferentially at the leading edges of positive protrusions and at the valleys of encroachments, implying that Stage I crack initiation sites are biased by the surface geometry. Interferometric observations show that PSB strain is inhomogeneous, being more highly localized at PSB-matrix interfaces, another phenomenon causing enhanced crack initiation.
Graphics and screen design for interactive learning

This paper concerns the role of graphics in computer based learning material. We consider both textual and graphic components of screen design and both spatial and temporal aspects. Informal design standards are developed. Several software approaches are discussed.
Measuring ESL readers’ ability to apply reasoning in reading: a validity study of the TOEFL reading comprehension subtest

This paper reports the results of an attempt to measure English as a Second Language (ESL) students’ability to apply reasoning in reading. The elicitation instrument was an experimental test which was developed from a model of reading comprehension based upon cognitive activities which Piaget referred to as concrete operations. The experimental test delineated Piaget's concrete operations in prose text and set them against difficulty criteria. The experimental test which measured the ability to apply reasoning in reading and the Test of English as a Foreign Language (TOEFL) were administered to a pool of adult ESL subjects. The results indicated that the TOEFL reading comprehension subtest does not measure the ability to apply reasoning in reading; thus, its validity as a measure of reading is in doubt. Significant effects were also shown for the paragraph types and the item types in the experimental test. The items based on the classification paragraphs were significantly more difficult than the items based on the serial paragraphs. In like manner, the items based on the multiplication paragraphs were significantly more difficult than the items based on the addition paragraphs. And finally, the intension questions which concerned the properties of a class were significantly more difficult than the extension questions which dealt with the members of classes. The results of this study indicate a need for further, increased attention to the measurement of reading to solve problems in ESL reading assessment and to the effects of the different structural organizations of ideas (e.g., addition, classification, multiplication, and series) and the interrelations of ideas on the comprehension process. The motivation for this line of research derives from the pragmatic interest of those researchers concerned with the communicative aspects of a text and the manner in which authors organize their ideas. Current research is beginning to explain the complex interaction between text structure and the reader's processing of such structure which further explicates the comprehension process.
Bronchial inhalation challenge with antigens.

In the following discussion, we will cover certain aspects of (1) antigen inhalation challenge with emphasis on clinical usefulness and (2) recent observations regarding methacholine and histamine inhalation challenges which have not been discussed by the other speakers at this Workshop. Due to time limitations we will present generalizations and hope that the details of these generalizations will emerge during subsequent sessions.
Seed Germination Response of Four Southwestern Range Grasses to Equilibration at Subgermination Matric‐Potentials

Seed priming at subgermination water potential has been shown to enhance the germination response of a wide number of plant species. Optimal priming conditions for germination enhancement are usually found to be at the least negative water potential that prevents radicle emergence. Equilibration of seeds at more negative water potentials may have detrimental effects on germination relative to control treatments. Seeds of Bouteloua curtipendula (Michx.) Torr., Cenchrus ciliaris L., Eragrostis lehmanniana Nees, and Panicum coloratum L. were equilibrated over the matrix potential range of -1.6 to -17.5 MPa and germinated over the matric potential range of 0 to -1.6 MPa. Matric-priming at -1.6 MPa frequently increased germination percentage and rate at reduced water potential []
Anatomical evidence of direct projections from the nucleus of the solitary tract to the hypothalamus, amygdala, and other forebrain structures in the rat

Ascending projections from the caudal (general-visceroceptive) part of the nucleus of the solitary tract (NTS) were studied experimentally in the rat by the aid of the anterograde autoradiographic and the retrograde horseradish peroxidase (HRP) tracer techniques. Microelectrophoretic deposits of tritiated proline and leucine which involved the caudal part of the NTS, the dorsal motor nucleus of the vagus (dmX), and portions of the hypoglossal nucleus, nucleus intercalatus and/or nucleus gracilis were found to label ascending fibers that, besides going to numerous brain stem territories that included prominently the parabrachial area, could also be traced to serveral forebrain structures, namely, the bed nucleus of the stria terminalis (BST), the paraventricular (PA), dorsomedial (HDM) and arcuate (ARC) nuclei of the hypothalamus, the central nucleus of the amygdaloid complex (AC), the medial preoptic area (PM) and the periventricular nucleus of the thalamus (TPV). Smaller isotope injections almost completely confined to the NTS and dmX resulted in lighter labeling of a similar set of parabrachial and forebrain projections, whereas in another case, in which the deposit was almost exclusively limited to the nucleus gracilis, no label was seen in the aforementioned structures. In another series of experiments, aimed at further localizing the neurons of origin of the prosencephalic projections under consideration, small microelectrophoretic HRP injections confined almost totally to BST, PA, HDM, AC, PM or TPV, as well as both small and large injections involving ARC, resulted in labeled neurons situated in the dorsal medullary region, mainly in the medial portion of the NTS at the level of and caudal to the area postrema. Taken together, these observations indicate for the first time the existence of relatively direct conduction lines by which interoceptive information might be conveyed to limbic forebrain structures; some of the possible physiological correlates of these anatomical findings are discussed.
Minimal Invasive Percutaneous Bipolar Radiofrequency for Plantar Fasciotomy: A Retrospective Study

The purpose of this study was to present the results of a relatively new, minimally invasive surgical technique for the treatment of chronic plantar fasciitis in 14 patients, 2 of whom underwent the treatment bilaterally one foot at time on separate occasions. This was a retrospective, multicenter, nonrandomized study. All of the patients had failed conservative therapy and had symptoms for at least 6 months. The mean follow-up duration was 15.25 months (range, 6-33 months). The postoperative mean American Orthopaedic Foot & Ankle Society hindfoot score was 82.06 (range, 56-100). None of the patients developed complex regional pain syndrome, and all but 2 (14.29% of patients, 12.5% of feet) of the patients were able to return to regular shoe gear by 2-4 weeks postoperative, and only 1 (7.14% of patients, 6.25% of feet) patient was considered a treatment failure. Based on our experience with minimally invasive percutaneous bipolar radiofrequency plantar fasciotomy, we believe the technique to be a relatively easy intervention that is effective and requires less healing time in comparison with traditional open surgical procedures.
Fixed point index for weakly inward mappings

Abstract The fixed point index for weakly inward mappings, which are not cone mappings, is defined in this paper. Its properties are also investigated. Consequently we study the derivatives of weakly inward mappings and nonzero fixed points of such mappings.
Myosin filamentogenesis: effects of pH and ionic concentration.

Abstract Filaments were formed from myosin extracted from rabbit striated muscle by rapidly diluting the KCl concentration to 0.3, 0.2 and 0.1 m . This was done at pH values ranging from 8.0 to 6.0. Preparations were examined in the electron microscope using the negative-staining technique, and in the analytical ultracentrifuge. The characteristics of the filaments formed are determined by the ionic concentration and pH; for each set of conditions a particular type of filament forms. At lower concentrations and pH values, long spindle-shaped filaments are formed, which are tapered, resembling natural thick filaments of striated muscle; the longest ones (1.8 μ average length) are formed at pH 6.5 in 0.1 m -KC1. At the higher ionic concentrations and pH, very short filaments are formed and free monomer is also present. Characteristic filaments of intermediate size (0.44 μ average length) with a relatively smooth central zone and gross irregular projections at the ends, are produced predominantly at pH 8.0 in 0.1 m -KCl (a high pH, low ionic concentration). Reproducible interconversions of filament types can be effected readily. Thus, the projections of the filaments in 0.1 m -KCl at pH 8.0 become leas prominent on lowering the pH to 6.5, some of the filaments becoming tapered, and also growing in size; monomer present at pH 8.0 now disappears. Other types of short filaments, co-existing with free monomer, also grow on lowering the pH. Conversely, long filaments dissociate into shorter ones plus monomer when pH is raised. Sedimentation coefficients for the various preparations are given. The significance of these findings is discussed.
Calcium, cellular aging, and selective neuronal vulnerability in Parkinson's disease

Parkinson's disease (PD) is the second most common neurodegenerative disease in developed countries. The core motor symptoms are attributable to the degeneration of dopamine (DA) neurons in the substantia nigra pars compacta (SNc). Why these neurons, and other restricted sets of non-dopamine neuron, succumb in PD is not clear. One potential clue has come from the observation that the engagement of L-type Ca2+ channels during autonomous pacemaking elevates the sensitivity of SNc DA neurons to mitochondrial toxins used to create animal models of PD, suggesting that Ca2+ entry is a factor in their selective vulnerability. Epidemiological data also supports a linkage between L-type Ca2+ channels and the risk of developing PD. This review examines the hypothesis that the primary factor driving neurodegenerative changes in PD is the metabolic stress created by sustained Ca2+ entry, particularly in the face of genetic or environmental factors that compromise oxidative defenses or proteostatic competence.
CranialCloud: a cloud-based architecture to support trans-institutional collaborative efforts in neurodegenerative disorders

Neurological diseases have a devastating impact on millions of individuals and their families. These diseases will continue to constitute a significant research focus for this century. The search for effective treatments and cures requires multiple teams of experts in clinical neurosciences, neuroradiology, engineering, and industry. Hence, the need to communicate a large amount of information with accuracy and precision is more necessary than ever for this specialty. In this paper, we present a distributed system that supports this vision, which we call the CranialVault Cloud (CranialCloud). It consists in a network of nodes, each with the capability to store and process data, that share the same spatial normalization processes, thus guaranteeing a common reference space. We detail and justify design choices, the architecture and functionality of individual nodes, the way these nodes interact, and how the distributed system can be used to support inter-institutional research. We discuss the current state of the system that gathers data for more than 1,600 patients and how we envision it to grow. We contend that the fastest way to find and develop promising treatments and cures is to permit teams of researchers to aggregate data, spatially normalize these data, and share them. The CranialVault system is a system that supports this vision.
Atmospheric Ions and Germination of Uredospores of Puccinia striiformis

Atmospheric ions, identified by mobility characteristics, were associated with germination of lyophilized uredospores of Puccinia striiformis West. at Bozeman Montana. Ions of intermediate size were highest in concentration, and percentage germination of spores was lowest during periods conducive to air pollution. In duplicate experiments at an isolated site near Barrow. Alaska, essentially all atmospheric ions were small ions and the fungus spores were consistently germinated near maximum.
ON ATTAINING ISOTHERMAL CONVECTIVELY COOLED SURFACES WITH REAR-SIDE, DISCRETE GROOVE-EMBEDDED HEATERS

Numerical solutions have been carried out to determine the temperature distribution along the exposed surface of a convectively cooled wall whose rear side is heated by a periodic array of groove-embedded heating elements. The accuracy of the numerical procedure was verified by using it to solve a related problem in which the heating occurs at discrete surface patches and then comparing those results with an exact solution. The numerical results for the exposed-surface temperature distributions corresponding to groove and patch heating were compared, and remarkably close agreement was found to prevail. This finding suggests that the computationally convenient exact solution for patch heating can be employed to obtain results for groove heating. The parameters which affect the uniformity of the temperature distribution on the convectively active surface were identified, and their quantitative influence was explored.
The use of flavor in cigarette substitutes

Cigarette smokers identify flavor as an important factor in the pleasure derived from smoking and for their choice of cigarette brand. The issue of cigarette flavor has received a great deal of study by cigarette manufacturers but relatively little by academic investigators. The paucity of literature is particularly acute in terms of the importance of flavor in cigarette substitutes, which are used to help people to reduce or quit smoking. In the current study, five different types of flavors added to a plastic cigarette substitute were assessed in experienced smokers. There were two menthol-like flavors and three tobacco-like flavors. Two groups of smokers were tested: menthol smokers and “regular” (non-menthol) smokers. Both types of smokers liked the two menthol flavors significantly more than placebo and rated the menthol flavors and the cigarette flavor as significantly more satisfying than placebo. Craving was differentially reduced in the two groups of smokers. Menthol smokers showed a small reduction in craving with the placebo, with a significant enhancement of this reduction seen with the addition of the “EZ Quit” menthol flavor.
A heuristic procedure for allocating tasks in fault‐tolerant distributed computer systems

One way of achieving the increased levels of system reliability and availability demanded by critical computer-based control systems is through the use of fault-tolerant distributed computer systems. This article addresses the problem of allocating a set of m tasks among a set of n processors in a manner that will satisfy various task assignment, system capacity, and task scheduling constraints while balancing the workload across processors. We discuss problem background, problem formulation, and a known heuristic procedure for the problem. A new solution-improving heuristic procedure is introduced, and computational experience with the heuristics is presented. With only a modest increase in the amount of computational effort, the new procedure is demonstrated to improve dramatically solution quality as well as obtain near-optimal solutions to the test problems.
Development and evaluation of problem frequency scales from version 3 of the computerized assessment system for psychotherapy evaluation and research (CASPER).

A comprehensive analysis of interview items on the Computerized Assessment System for Psychotherapy Evaluation and Research (CASPER) was conducted using derivation (N = 1, 168) and cross-validation samples (N = 1, 158) from a university counseling center and an outpatient training clinic sample (N = 355). Nine scales were identified that demonstrated acceptable internal consistency and unidimensionality. Confirmatory factor analyses of 6 of these scales supported the presence of 6 factors, but indicated that several were highly intercorrelated. These findings were consistent across all 3 samples. Analyses relating these 6 scales to comparable scales on the Brief Symptom Inventory (BSI) obtained for the training clinic sample indicated a high degree of correspondence across instruments. In addition, significant correlations were found between global measures obtained from CASPER and the BSI.
Myocardial kinetics of radiolabeled perfusion agents: Basis for perfusion imaging

The myocardial deposition of radiolabeled perfusion agents permits the noninvasive assessment of regional coronary blood flow. The design of imaging protocols and the optimal interpretation of clinical perfusion studies are based on an understanding of the kinetics of blood-tissue exchange for these compounds. Thallium 201 and the technetium 99m-labeled compounds sestamibi, teboroxime, and tetrofosmin show differing myocardial extraction and retention. This review focuses on studies that used cell culture, isolated heart, and intact animal models that form the basis of our current understanding of the myocardial kinetics of these imaging agents.
Against the Tedium of Immortality

Abstract In a well-known paper, Bernard Williams argues that an immortal life would not be worth living, for it would necessarily become boring. I examine the implications for the boredom thesis of three human traits that have received insufficient attention in the literature on Williams’ paper. First, human memory decays, so humans would be entertained and driven by things that they experienced long before but had forgotten. Second, even if memory does not decay to the extent necessary to ward off boredom, once-satisfied desires often return after a sufficient period of time. Eternity would always contain sufficient time for our desires to rejuvenate. Third, even if too many of our desires were satisfied but not yet rejuvenated, we can expect that human ingenuity would continue to invent new pursuits, pastimes, careers, and ways of life that would prevent us from becoming bored as we moved from one to another. Finally, I consider and respond to several objections, including the claims that as much variet...
The interline heat-transfer coefficient of an evaporating wetting film

Abstract The average evaporation heat-transfer coefficient for the interline region of an adsorption controlled wetting film in which the disjoining pressure is approximated by P d =− A δ −3 can be represented bykh=hid[1−O.5(η−1+η−2)].hid is the ideal liquid-vapor interfacial heat-transfer coefficient and η is a function of the physical properties of the system and the extent of the interline region. A simple procedure to obtain the heat-transfer coefficient is presented. The coefficient varies from zero at the interline to a value equal to the liquid-vapor interfacial heat-transfer coefficient over a relatively short distance.
Clinical use of the erythrocyte sedimentation rate in the evaluation of febrile intravenous drug users

Study objective: To investigate the use of the erythrocyte sedimentation rate in the evaluation of febrile IV drug users. Design: Prospective observational cohort study. Setting: Municipal hospital emergency department. Type of participants: One hundred six IV drug users aged 18 years or older, with rectal temperatures of 37.8 C or more. Interventions: Clinical and laboratory variables were obtained by trained research assistants, using a standardized data collection instrument. Results: The erythrocyte sedimentation rate was the only variable consistently associated with illness severity in both the univariate and multivariable analyses ( P Conclusion: An erythrocyte sedimentation rate of 100 or more should be regarded as a marker for serious illness in IV drug users with fever, but a "normal" erythrocyte sedimentation rate of less than 20 does not reliably exclude the presence of serious disease in this patient population.
In vitro reductive metabolism of N-nitrosodibenzylamine: evidence for new reactive intermediates.

Abstract N-Nitrosodibenzylamine was incubated with rabbit-whole-liver homogenates. Gas-chromatographic and mass spectrometric analysis of the incubation extracts showed the formation of bibenzyl. This biotransformation is the result of a 2-electron reduction of the substrate to 1-hydroxy-2,2-dibenzylhydrazine, an unstable compound which breaks down to bibenzyl and nitrogen. It is suggested that such reductive metabolism may be involved in the generation of toxic metabolites of nitrosamines.
An alteration in the kinetic properties of a cholesterogenic enzyme in fowlpox virus infection.

Abstract Cholesterogenesis in the chorioallantoic membrane (CAM) of the chick embryo during fowlpox virus infection has been studied by a variety of techniques. Analysis of the sterol content of the CAM epithelium revealed an elevation in the sterol content on the fourth day postinfection, but not on the third day. The increase was due primarily to the accumulation of sterol ester. That the increased level of sterols is due to an increase in synthetic rate is suggested by the observation that the activity of the enzyme usually considered to be rate limiting in cholesterogenesis, 3-hydroxy,3-methylglutaryl coenzyme A (HMG-CoA) reductase, becomes elevated above control values at about this same time period, i.e., between 3 and 4 days postinfection. The ability to synthesize sterol from labeled mevalonate is lower in the infected tissue than in the control. These data indicate that the HMG-CoA reductase reaction may be a primary site of action in the stimulation of cholesterogenesis in fowlpox virus infection. An examination of the kinetic properties of the HMG-CoA reductase from infected CAM epithelium suggested that two forms of the enzyme are present in infected cells, one form identical to the control enzyme- and an altered form. This conclusion was based on the biphasic nature of the saturation curve of the enzyme for HMG-CoA. Other kinetic properties such as thermal denaturation and pH titration also revealed differences between the enzymes from control and infected tissues.
On the interpretation of the 'inverse phase effect' for CO2 equivalent widths on Venus

Computations of the equivalent widths of absorption lines as a function of planetary phase angle are made for a homogeneous cloud with particles having the properties (shape, refractive index, and size distribution) deduced from polarimetry of Venus. The computed equivalent widths show an 'inverse phase effect' comparable to that which is observed for CO2 lines on Venus. This result verifies a recent suggestion of Regas et al. that the existence of an inverse phase effect does not by itself imply the presence of multiple layers of scattering particles in the atmosphere of Venus.
Discrimination of chirp vocalizations in the cotton-top tamarin

Natural exemplars of two types of chirp vocalizations were presented to eight groups of cotton-top tamarins (Saguinus o. oedipus) in a playback paradigm. The two chirps share many acoustic features in common but are used in entirely different circumstances. The tamarins gave different vocal and behavioral responses to the playbacks of each chirp type, indicating that a discrimination was made. The results suggest that tamarins can discriminate subtle acoustic cues which have communicative significance. In the absence of the nonvocal cues and social contexts that normally co-occur with these vocalizations the tamarins responded with the same vocal responses they would have given in normal social contexts. Significant differences in post-stimulus behavior to the two types of stimuli appeared in the first two blocks of trials, indicating that the playback paradigm can be an efficient means of testing discrimination between different call types.
Grappling with the evaluation of clinical competencies: a view from the residency review committee for urology

We sought to highlight the perspective of the Residency Review Committee for Urology regarding the current changes in residency program accreditation. Although the pedagogic underpinnings of the shift of the American Committee for Graduate Medical Education to outcomes-based accreditation appear solid, several concerns were raised by the Residency Review Committee for Urology: the paucity of effective evaluation tools, the likely increased expense of these measures, and the lack of evidence that these changes will ultimately improve the training of residents. As a result, the Committee plans to continue cautiously (but optimistically) in the process of incorporating the teaching and evaluation of the clinical competencies in the program requirements.
Study of the effectiveness of stereo imaging with applications in mammography

We have conducted a systematic study of the effectiveness of stereo imaging in aiding the detection of abnormalities in soft tissue geometry and density. Experiments have been designed whereby subjects are shown computer generated stereo mammograms and are asked to determine if there is an abnormal object (brighter or regularly arranged) in the mammogram. The experimental data have been analyzed using ROC approaches to determine which types of soft tissue abnormalities may be easier to detect using stereo viewing. Preliminary results suggest that stereo imaging may be more effective than current single view or biplane mammography for detecting abnormal densities and arrangements in soft tissue elements.
Suppression of feeding and body weight by inescapable shock: Modulation by quinine adulteration, stress reinstatement, and controllability

Abstract Three experiments examined food intake and body weight in rats after exposure to one session of intermittent, inescapable electric shock. Quinine adulteration and shock both suppressed feeding (Experiment 1); recovery of feeding after shock was impeded when quinine adulteration was combined with a mild daily stress reinstatement (Experiment 2). Body weight also was suppressed by shock (Experiments 1 and 2); control over shock provided some protection against this deficit (Experiment 3). These results suggest roles for “finickiness” and vulnerability to mild stressors in the maintenance of eating disorders associated with stress and depression. The findings also may have implications for interpretation of deficits in appetitively motivated behaviors after stress.
Iodoproteins in thyroid tissue and blood of rats with a transplantable thyroid tumor.

lodoprotcins other than thyroglobulin have been detected in a transplantable rat thyroid tumor (Wollman) in which iodine compounds were labeled with I131 cither in vivo or in vitro. Two types of iodoprotein were found. One was not extractable from glass homogenized tissue by 0.15 M NaCl, and is termed “particulatc iodoprotein, ” or “P-l.” In in vivo experiments, it increased with time after I131 administration from about 15% to about 70% of the total organic iodine in the tumor. Cell particle fractionation identified this material with the “nuclear” fraction. The second type of iodoprotein was readily extracted from previously frozen (tissue slices. Unlike thyroglobulin, it was soluble in 1.89.M KH2PO4 – K2(HPO.4 sedimented slowly in the ultracentrifuge, and appeared multidispcrse on zone electrophoresis. This iodoprotein fraction comprised 3 to 9% of the soluble ido-proteins, the remainder being thyroglobulin, and its amount relative to thyro-globulin did not change with time after I131 administration. I...