cssi/SciSciGPT-SciSciNet huggingface dataset:
Diversity and Distribution of Sulfur Metabolism 1 in the Human Gut Microbiome and its Association with Colorectal Cancer

Microbial sulfidogenesis produces genotoxic hydrogen sulfide (H2S) in the human gut using inorganic (sulfate) and organic (taurine/cysteine/methionine) substrates, however the majority of studies have focused on sulfate reduction using dissimilatory sulfite reductases (Dsr). Recent evidence implicates microbial sulfidogenesis as a potential trigger of colorectal cancer (CRC), highlighting the need for comprehensive knowledge of sulfur metabolism within the human gut. Here we show that microbial sulfur metabolism is more abundant and diverse than previously studied and is statistically associated with CRC. Using ~17,000 bacterial genomes from publicly available stool metagenomes, we studied the diversity of sulfur metabolic genes in 667 participants across different health statuses: healthy, adenoma, and carcinoma. Sulfidogenic genes were harbored by 142 bacterial genera and both organic and inorganic sulfidogenic genes were associated with carcinoma. Significantly, anaerobic sulfite reductases were twice as abundant as dsr. We identified twelve potential pathways for reductive taurine metabolism including novel pathways, and prevalence of organic sulfur metabolic genes indicate these substrates may be the most abundant source of microbially derived H2S. Our findings significantly expand knowledge of microbial sulfur metabolism in the human gut, and highlight key gaps that limit understanding of its potential contributions to the pathogenesis of CRC.
Production of specific agglutinins for mycobacteria in peritoneal fluid of mice.

Abstract Specific agglutinins were produced in ascitic fluid of mice by intraperitoneal injection of certain mycobacteria suspended in Freund's incomplete adjuvant.
Kinetic studies with transglutaminases. The human blood enzymes (activated coagulation factor 13 and the guinea pig hair follicle enzyme.

The transfer reaction of [14C]methylamine into the acetylated B chain of oxidized insulin as catalyzed by several transglutaminases has been studied at pH 7.5 in the presence of calcium ion. The only radioactive product of the transfer reaction with each transglutaminase was identified as peptide-bound γ-glutamic acid methylamide. Initial velocity and product inhibition patterns for the human plasma and guinea pig hair follicle transglutaminases are consistent with a ping-pong mechanism, previously proposed for guinea pig liver transglutaminase (F olk , J. E. (1969) J. Biol. Chem. 244, 3707) in which acyl enzyme formed from peptide-bound glutamine may react with water (hydrolysis) or with a primary amine (transfer). Hydrolysis and isotope exchange in the presence of one substrate and one product add substantial support for this mechanism. The pattern of calcium activation of plasma transglutaminase in the transfer reaction is in accord with an equilibrium-ordered activation mechanism in which the first substrate, acetylated B chain of oxidized insulin, adds only to enzyme-metal complex. The similarity in the kinetic constants obtained for human plasma and platelet transglutaminases adds support to recent evidence that the catalytic subunits of the plasma and platelet zymogens and enzymes are closely related (S chwartz , M. L., P izzo , S. V., H ill , R. L., and M c K ee , P. A. (1971) J. Biol. Chem. 246, 5851). Improved purification procedures for plasma and platelet protransglutaminases are presented.
Exploring the Fourth Dimension: a Computer Scientist's Experience in Temporal Display Development

A new interface paradigm is required for effective supervisory control of multiple unmanned vehicles by a single operator. A temporal-based display is potentially useful for these time-critical cognitively demanding task environments. However, designs of candidate temporal interfaces for unmanned vehicles have been limited and related publications have not described the approaches used by computer scientists in the development of these interfaces. Recently, a temporal display was designed and implemented that will soon undergo extensive evaluation. This paper documents the design decisions made in the course of developing this interface in regards to the underlying temporal data structures and how they are organized and updated. 1
Biomechanics of leukocyte rolling

Leukocyte rolling on endothelial cells and other P-selectin substrates is mediated by P-selectin binding to P-selectin glycoprotein ligand-1 expressed on the tips of leukocyte microvilli. Leukocyte rolling is a result of rapid, yet balanced formation and dissociation of selectin-ligand bonds in the presence of hydrodynamic shear forces. The hydrodynamic forces acting on the bonds may either increase (catch bonds) or decrease (slip bonds) their lifetimes. The force-dependent 'catch-slip' bond kinetics are explained using the 'two pathway model' for bond dissociation. Both the 'sliding-rebinding' and the 'allosteric' mechanisms attribute 'catch-slip' bond behavior to the force-induced conformational changes in the lectin-EGF domain hinge of selectins. Below a threshold shear stress, selectins cannot mediate rolling. This 'shear-threshold' phenomenon is a consequence of shear-enhanced tethering and catch bond-enhanced rolling. Quantitative dynamic footprinting microscopy has revealed that leukocytes rolling at venular shear stresses (>0.6 Pa) undergo cellular deformation (large footprint) and form long tethers. The hydrodynamic shear force and torque acting on the rolling cell are thought to be synergistically balanced by the forces acting on tethers and stressed microvilli, however, their relative contribution remains to be determined. Thus, improvement beyond the current understanding requires in silico models that can predict both cellular and microvillus deformation and experiments that allow measurement of forces acting on individual microvilli and tethers.
Neutralización del contraste entre /ɲ/ y /nj/ en el español de Buenos Aires: Un estudio de percepción

El espanol tiene tres fonemas nasales, /m n ɲ/, que son contrastivos en el ataque de silaba, por ejemplo en las palabras cama , cana y cana . Varios autores (Colantoni y Hualde 2013; Kochetov y Colantoni 2011; Malmberg 1950) comentan sobre una tendencia del espanol de Buenos Aires a neutralizar la nasal palatal con la secuencia nasal y deslizada, /n+j/, tal que las palabras uranio /uɾanio/ y hurano /uɾaɲo/ se producen de manera equivalente. El presente estudio investiga estos reportes de neutralizacion mediante un estudio de percepcion y examina tres hipotesis: contraste, neutralizacion completa y neutralizacion incompleta. Treinta y tres hablantes nativos del espanol de Buenos Aires realizaron dos tareas de percepcion, una tarea ABX y una tarea de dictado, en la que debian distinguir entre /ɲ/, /n+j/ y /n/, producidas por hablantes portenas y mexicanas. Los resultados de las dos tareas indican que los participantes distinguen entre /ɲ/ y /n/ y entre /n+j/ y /n/, pero no entre /ɲ/ y /n+j/. Asimismo, no se observaron diferencias de acuerdo al sexo del participante, grupo etario o dialecto del estimulo. Estos resultados son compatibles con la hipotesis de que /ɲ/ y /n+j/ estan total o incompletamente neutralizados.
Non-Memory-Based and Real-Time Zerotree Building for Wavelet Zerotree Coding Systems

The wavelet zerotree coding systems, including Embedded Zerotree Wavelet (EZW)[1] and its variants Set Partitioning In Hierarchical Trees(SPIHT)[2] and Space Frequency Quantization (SFQ)[3][4], have three common procedures: 1) 2-D Discrete Wavelet Transform (DWT)[5], 2) zerotree building and symbol generation from the wavelet coefficients (illustrated in Figure 1), and 3) quantization of the magnitudes of significant coefficients and entropy coding, where the second procedure is an important one. All recently propsed architectures ([6]–[9]) for wavlelet zerotree coding use memories to build zerotrees. In this paper we con tribute to building the zerotrees in a non-memory-based way with real-time performance leading to the decrease of hardware cost and the increasement of processing rate which is especially desirable in video coding. One of our main ideas is to rearrange the DWT calculations taking advantage of parallel and pipelined processing so that any parent coefficient and its children coefficients in zerotrees are guaranteed to be calculated and outputted simultaneously.
Continuous Fiber Reinforced Composite Materials as Alternatives for Metal Alloys Used for Dental Appliances

Two types of uniaxially oriented long S2-glass fiber reinforced composites were prepared for use in various dental appliances. Matrix polymers were polycarbonate (PC) and bisphenol A bis (2-hydroxy-propyl) methacrylate (Bis-GMA) based copolymers. Flexural tests were conducted on the composites using a procedure which simulates clinical usages. To evaluate the adhesion between the composites and the adhesive, the single-lap shear test was conducted. Mechanical properties of the small cross-sectional composite strips were superior to those used previously in clinical studies.
Protein synthesis in rat brain in hypoxia, anoxia and hypoglycemia

The effect of cerebral hypoxia on protein synthesis was investigated by exposing rats to 5% O2, and examining polypeptide synthesis and size distribution profiles of ribosomes. The findings were compared with the results from cerebral anoxia (decapitation) and hypoglycemia. In cerebral hypoxia there was suppression of polypeptide synthesis, though to a lesser extent than in cerebral anoxia, while no effect was detected in hypoglycemia. Among 4 different ribosomal fractions used for polypeptide synthesis, the microsome was the most sensitive for hypoxia and anoxia, and the polyribosome after short centrifugation was the least sensitive. The size distribution profiles of 3 different ribosomes revealed an increase in the size of the monomere-dimer complex and a decrease of the polysome peak both in cerebral hypoxia and anoxia. Comparison of the energy state and the extent of lactic acidosis in cerebral hypoxia, anoxia and hypoglycemia available in the literature and the functional and structural state of polyribosomes in the present investigation suggests that intracellular acidosis may be the main cause of the suppression of polypeptide synthesis and disaggregation of polyribosomes in hypoxia, and the depletion of energy reserve may be the main cause in anoxia-ischemia.
Phase-front measurements of an injection-locked AlGaAs laser-diode array.

The phase-front quality of the primary spatial lobe emitted from an injection-locked gain-guided AlGaAs laser-diode array is measured by using an equal-path, phase-shifting Mach-Zehnder interferometer. Root-mean-square phase errors of 0.037 + or - 0.003 wave are measured for the single spatial lobe, which contained 240-mW cw output power in a single longitudinal mode. This phase-front quality corresponds to a Strehl ratio of S = 0.947, which results in a 0.23-dB power loss from the single lobe's ideal diffraction-limited power. These values are comparable with those measured for single-stripe index-guided AlGaAs lasers.
Acute lung injury induced by Pseudomonas aeruginosa elastase in hamsters.

Human neutrophil elastase (HNE) is the predominant elastolytic enzyme in the sputum of cystic fibrosis (CF) patients. However, a variably small portion of the activity can be ascribed to Pseudomonas aeruginosa elastase (PaE). The purpose of these studies was to evaluate the activities of the two elastases in an in vivo model of acute lung injury (ALI), The elastolytic activity of Pseudomonas aeruginosa elastase (MW = 39K) and human neutrophil elastase (MW = 33K) were also examined using insoluble bovine neck and lung elastin. The ability of hamster serum to inhibit elastinolysis by the two elastases was also examined. On a per milligram protein basis, PaE was the more potent elastase, regardless of substrate, and it preferentially hydrolyzed lung relative to neck elastin. PaE is poorly inhibited by hamster serum compared to HNE. In vivo, PaE is much more efficient than HNE in inducing an acute lung injury in hamsters. The duration of effects induced by doses of the two proteases that produce similar acute...
School Quality and the Education-Health Relationship: Evidence from Blacks in Segregated Schools

In this paper, we estimate the effect of school quality on the relationship between schooling and health outcomes using the substantial improvements in the quality of schools attended by black students in the segregated southern states during the mid-1900s as a source of identifying variation. Using data from the National Health Interview Survey, our results suggest that improvements in school quality, measured as the pupil-teacher ratio, average teachers' wage, and length of the school year, amplify the beneficial effects of education on several measures of health in later life, including self-rated health, smoking, obesity, and mortality.
Oxidation Properties of (U, Pu)O2 Solid Solutions

Air oxidation of (U, Pu)O2 solid solutions having Pu/(U+Pu) ratios of 0.2 and 0.25 was studied using a recording thermal balance. For Pu/(U+Pu)=0.2, the original fluorite MO2 phase oxidized first to tetragonal M3O7; further oxidation at 450°C<T<600°C gave a two-phase mixture of M'3O8 and a cubic phase having a0≃5.43 A. Kinetic analysis of these oxidation stages indicated that the Erofeev nucleation model explains the data reasonably well, with ΔH≃40 kcal/mol for the formation of M3O7 and ΔH≃40 kcal/mol for the oxidation of M3O7 to M'3O8+ the cubic phase. Oxidation above M3O7 (O/M=2.35) resulted in mechanical disintegration of the samples because of the presence of the M'3O8 phase. For Pu/(U+Pu) = 0.25, both isothermal and programed air oxidation of homogeneous samples up to 800°C led to a compound with a maximum O/M≃2.35, i.e. M4O9.4, an fcc phase having a0=5.428 A; these samples were not converted to powder by the oxidation.
Determinization and Memoryless Winning Strategies

We show that Safra's determinization of?-automata with Streett (strong fairness) acceptance condition also gives memoryless winning strategies in infinite games, for the player whose acceptance condition is the complement of the Streett condition. Both determinization and memorylessness are essential parts of known proofs of Rabin's tree automata complementation lemma. Also, from Safra's determinization construction, along with its memoryless winning strategy extension, a single exponential complementation of Streett tree automata follows. A different single exponential construction and proof first appeared in N. Klarlund (1992), Progress measures, immediate determinacy, and a subset construction for tree automata,in“Proceedings, 7th IEEE Symposium on Logics in Computer Science”].
Type systems for querying class hierarchies with non-strict inheritance

Type checking at query compilation time is important for both detecting programmer errors and reducing the running time of queries. We have argued elsewhere [2] that entity-based data management systems which support class hierarchies, such as semantic data models and object-oriented dbms, should not be confined to have “strict inheritance” — i.e., they should permit contradictions between class specifications, albeit in an explicit and controlled way. In this paper we present a type system for queries manipulating objects in such classes. We provide sound and complete axiomatizations of the predications “s is a subtype of t” and “expression e has type t”. The absence of strict inheritance has normally been felt to preclude effective type checking. We show that the problem is co-NP-hard when disjoint types are admitted in the schema, but present a low-order polynomial-time algorithm that determines the absence of type errors in a query when the database has only entities.
In vitro assessment of interaction of blood with model surfaces: Acrylates and methacrylates

Abstract Polymers synthesized from alkyl acrylates and alkyl methacrylates (alkyl = methyl, ethyl, propyl, …, lauryl) were deposited from solution as coatings on surfaces of glass beads packed into columns. Surfaces were exposed to citrated human blood, in some cases after prior incubation with platelet-poor plasma (PPP). The average platelet recovery index,r¯(r¯= effluent platelet count/influent platelet count), was determined. For both polyacrylates and polymethacrylates,r¯decreased with increasing number of carbons in the alkyl group, being highest for alkyl = methyl. The degree of secretion of platelet constituents varied directly with length of the alkyl side chain. Incubation with PPP increased P. Results are interpreted in terms of hydrophilic-hydrophobic balance of the polymer surfaces and plasma protein adsorption.
High-permittivity lead-based perovskite dielectrics for DRAM applications

Abstract Suppression of the nonvolatile polarization in lead zirconate titanate films by La doping or by use of films 100 nm or less in thickness provides the highest charge storage densities yet observed. These films also satisfy leakage current density and TDDB requirements for very high density DRAMs, and show good resistance to fatigue.
Functional characterization of two cold shock domain proteins from Oryza sativa

Two novel rice cold shock domain (CSD) proteins were cloned and characterized under different stress treatments and during various stages of development. OsCSP1 and OsCSP2 (Oryza sativa CSD protein) encode putative proteins consisting of an N-terminal CSD and glycine-rich regions that are interspersed by 4 and 2 CX(2)CX(4)HX(4)C (CCHC) retroviral-like zinc fingers, respectively. In vivo functional analysis confirmed that OsCSPs can complement a cold-sensitive bacterial strain which lacks four endogenous cold shock proteins. In vitro ssDNA binding assays determined that recombinant OsCSPs are capable of functioning as nucleic acid-binding proteins. Both OsCSP transcripts are transiently up-regulated in response to low-temperature stress and rapidly return to a basal level of gene expression. Protein blot analysis determined that OsCSPs are maintained at a constant level subsequent to a cold treatment lasting over a period of several days. Both the transcript and protein data are in sharp contrast to those previously obtained for winter wheat WCSP1. A time-coursed study through various stages of rice development confirmed that both OsCSP proteins and transcripts are highly accumulated in reproductive tissues and tissues which exhibit meristematic activity.
Wisconsin Glaciation of the Sierra Nevada (79,000-15,000 yr B.P.) as recorded by rock flour in sediments of Owens Lake, California

Chemical analyses of the clay-sized fractions of 564 continuous sediment samples (200-yr resolution) from composite core OL90/92 allow quantification of an abundance of glacial rock flour. Rock flour produced during glacier advances is represented by clay-sized plagioclase, K-feldspar, and biotite in homogeneous internal composition. The abundance of rock flour is deemed proportional to the intensity of glacies advances. Age control for the composite section is provided by combining previously published radiocarbon dates on organics, U/Th dates on ostracode shells, and U/Th dates on saline minerals from nearby Searles Lake correlated to OL92 by pollen. The rock flour record displays three levels of variability: (1) a dominant one of about 20,000 yr related to summer insolation and precipitation; (2) an intermediate one of 3000–5000 yr, perhaps related to North Atlantic Heinrich events; and (3) a minor one of 1000–2000 yr, perhaps related to North Atlantic thermohaline-driven air-temperature variation.
High general anger : Correlates and treatment

Abstract Two studies on high general anger are reported. In Study 1 high anger Ss reported significantly more general anger, situational anger, anger-related physiological arousal, frequency and intensity of daily anger and general anxiety than low anger S s. In response to provocation, heart rates (HRs) did not differ, but high anger S s reported more state anger and tendencies to be verbally and physically antagonistic and lowered tendency to cope constructively. A regression on general anger revealed that general anxiety, coping through verbal antagonism, and average daily level of anger entered the regression and accounted for 70% of the variance. In Study 2, high anger was treated with a relaxation coping skills intervention. Compared to controls, treated S s reported less general and situational anger, and less state anger, verbal and physical antagonism and greater constructive coping when provoked. These gains were maintained at 5-week and 1-year follow-ups. Groups did not differ on HR when provoked, daily anger ratings or trait anxiety. One-year follow-up, however, revealed significantly lower general anxiety for treated S s. Results were discussed in terms of the characteristics of high anger S s, the role of general anxiety in general anger and the usefulness of self-control relaxation approaches for anger reduction.
Video transmission in optical fiber communication systems using pulse frequency modulation

A design procedure has been developed to determine the required operating conditions for a pulse-frequency modulation (PFM) system (modulation index, required system bandwidth, and receiver carrier-to-noise ratio (CNR) for a specified receiver SNR (signal-to-noise ratio) and number of clicks per second. The PFM processing gain (=SNR/CNR) was measured to be 40 dB for a modulation index of beta =2.5, which agrees closely with the theory. The theoretical processing gain advantage of PFM over FM is 15.9 dB for a modulation index of beta =2.5 with receiver bandwidth B/sub rx/=50 MHz. >
Sensitivity of Sweetpotato Weevil (Coleoptera: Curculionidae) to Gamma Radiation

Effects of gamma radiation on the sweetpotato weevil, Cylas formicarius elegantulus (Summers), were studied. Depending on stage of the weevil, doses of 5, 10, 20, 35, 50, 75, and 100 krad were used. Eggs irradiated at 5–20 krad were unable to develop to the larval stage at any treatment level. Twelve-day-old larvae were unable to develop to the pupal stage when irradiated at > 5 krad and no adults emerged at any treatment level between 5 and 50 krad. When 5-day-old pupae were irradiated, no normal adults emerged at > 35 krad. A dose of 5 krad in the pupal stage was enough to cause sterility in adults. Higher temperature accelerated mortality at all doses and survival time of irradiated adults decreased with increasing dose. After exposure to 100 krad, adults did not feed and all died within 7 days at 32°C and 11 days at 27°C. At 75 krad, adults died in 14 days at 32°C and in 18 days at 27°C. Reproductive ability of irradiated adults was considerably reduced at 5 krad. Complete sterility occurred in females at 20 krad and in males at 30 krad.
Structural settings of hydrothermal outflow: Fracture permeability maintained by fault propagation and interaction

Hydrothermal outflow occurs most commonly at the terminations of individual faults and where multiple faults interact. These areas of fault propagation and interaction are sites of elevated stress termed breakdown regions. Here, stress concentrations cause active fracturing and continual re-opening of fluid-flow conduits, permitting long-lived hydrothermal flow despite potential clogging of fractures due to mineral precipitation. As fault systems evolve, propagation, interaction, and linkage of fault segments result in the migration and eventual localization of breakdown regions in kinematically favorable sites such as fault bends or fault intersections. Concurrent migration of hydrothermal outflow sites along with these areas of elevated permeability leads to predictable patterns of hydrothermal deposition along fault zones. Thus, the distribution of active outflow sites and preserved deposits along fault zones can potentially provide a tool for studying fault-zone evolution.
Survival Trends in Patients With Gastric and Esophageal Adenocarcinomas: A Population-Based Study

OBJECTIVE To use a population-based approach to describe survival trends in patients diagnosed as having gastric or esophageal adenocarcinoma. PATIENTS AND METHODS A population-based complete chart review of all inpatient and outpatient records, using the resources of the Rochester Epidemiology Project, was conducted in Olmsted County, Minnesota (population 124,277), a primarily rural county with one large urban area. All residents of Olmsted County who were diagnosed as having gastric or esophageal adenocarcinoma from January 1, 1971, through December 31, 2000, were included in the study. The main outcomes were median survival and 2-year and 5-year survival rates, by decade of diagnosis. RESULTS From 1971 through 2000, median survival for patients with gastric adenocarcinoma (n=121) decreased from 5.5 months to 3.2 months, whereas median survival for patients with esophageal adenocarcinoma (n=65) increased from 8.5 months to 11.7 months. Decade of diagnosis was not significantly associated with patient survival for either gastric or esophageal adenocarcinoma ( P >.05). There was no significant shift in stage of disease at diagnosis during the 30-year period for either gastric or esophageal adenocarcinoma ( P >.05). CONCLUSION No significant change has occurred in the survival rates of this patient population with gastric or esophageal adenocarcinoma, which is representative of the US white population.
Research, Patents, and the Struggle to Control Radio: A Study of Big Business and the Uses of Industrial Research. "

The advent of high-technology industries around the turn of the century created the modern industrial research department and placed a new emphasis upon the search for patentable innovations. While some of this research led to advances in basic scientific knowledge, and much of it produced product or process improvements that were directly applicable to a firm's business, a great deal was undertaken to enhance firms' bargaining powers with each other in order to preserve monopoly positions. In the early years of radio, the structure of the industry changed repeatedly with every innovation in apparatus or circuitry, a situation that led, as Professor Reich shows, to heavy investment in “non-productive” research.
Undescribed genera and species of Harpellales (Trichomycetes) from the guts of aquatic insects

Eight new species of the fungal order Harpellales from the United States are described, including three new monotypic genera (Genistellospora, Trichozygospora, and Simuliomyces). Three species are ...
Reaction Time as a Behavioral Demonstration of Neural Mechanisms for a Large Introductory Psychology Class

A straightforward and effective demonstration of the difference between simple and disjunctive reaction times (RTs) is provided. Several volunteers from a large class are assigned to a control group and instructed to raise their left hands upon hearing the name of a United States president. A comparable experimental group of subjects raise their left hands if the president served after Abraham Lincoln or their right hands if the president preceded Lincoln. Faster RTs to the name Ford occur for subjects in the control group, indicating conduction over more neurons and synaptic delay when a choice of responses is required.
Localized electrons in molecular aggregates

Abstract Electron localization in molecular aggregates is related to two independent physical concepts. One is the non-periodicity of the system and the other is the dynamic concept of electron-phonon interaction. These two concepts are separately investigated in terms of one-dimensional models. The effect of localized states on the quasi-free state, V 0 , is also discussed.
Fast algorithms for generating discrete random variates with changing distributions

One of the most fundamental operations when simulating a stochastic discrete-event dynamic system is the generation of a nonuniform discrete random variate. The simplest form of this operation can be stated as follows: Generate a random variable X that is distributed over the integers 1,2,…,n such that P(X=i) = ai/(a1 +…+an), where ai's are fixed nonnegative numbers. The well-known “alias algorithm” is available to accomplish this task in O(1) time. A more difficult problem is to generate variates for X when the ai's are changing with time. We present three rejection-based algorithms for this task, and for each algorithm we characterize the performance in terms of acceptance probability and the expected effort to generate a variate. We show that, under fairly unrestrictive conditions, the long-run expected effort is O(1). Applications to Markovian queuing networks are discussed. We also compare the three algorithms with competing schemes appearing in the literature.
Keynote Address: Improving the Science and art of Risk Assessment

(1996). Keynote Address: Improving the Science and art of Risk Assessment. Drug Metabolism Reviews: Vol. 28, No. 1-2, pp. 1-7.
Volatile biomarkers from human melanoma cells.

Dogs can identify, by olfaction, melanoma on the skin of patients or melanoma samples hidden on healthy subjects, suggesting that volatile organic compounds (VOCs) from melanoma differ from those of normal skin. Studies employing gas chromatography–mass spectrometry (GC–MS) and gas sensors reported that melanoma-related VOCs differed from VOCs from normal skin sources. However, the identities of the VOCs that discriminate melanoma from normal skin were either unknown or likely derived from exogenous sources. We employed solid-phase micro-extraction, GC–MS and single-stranded DNA-coated nanotube (DNACNT) sensors to examine VOCs from melanoma and normal melanocytes. GC–MS revealed dozens of VOCs, but further analyses focused on compounds most likely of endogenous origin. Several compounds differed between cancer and normal cells, e.g., isoamyl alcohol was higher in melanoma cells than in normal melanocytes but isovaleric acid was lower in melanoma cells. These two compounds share the same precursor, viz., leucine. Melanoma cells produce dimethyldi- and trisulfide, compounds not detected in VOCs from normal melanocytes. Furthermore, analyses of the total volatile metabolome from both melanoma cells and normal melanocytes by DNACNT sensors, coupled with the GC–MS results, demonstrate clear differences between these cell systems. Consequently, monitoring of melanoma VOCs has potential as a useful screening methodology.
Technical Communique: Wavelet-Based Identification of Linear Discrete-Time Systems: Robustness Issue

Discrete-time linear time-varying systems are modeled by discrete-time wavelets. The output of the unknown system is corrupted by noise. The system model parameters are estimated by the least-squares method applied to the output error. Conditions are derived that provide vanishing influence of the output noise to the parameter estimates. Due to the time-frequency selectivity of wavelets, parameter estimates can be robust to narrow-band noise and/or impulse noise. This robustness is confirmed by simulations.
On the crushing stress of open cell foams

The compressive response of many foams is characterized by an initial linearly elastic regime which is terminated by instability. For open cell foams instability leads to localized buckling and collapse of zones of cells. Local collapse in these zones is terminated by contact between cell ligaments. In the process collapse spreads to neighboring cells hitherto intact. The spreading of collapse occurs at a well-defined load plateau and continues until most of the cells are thus affected when the material response regains stiffness once more. This type of three-regime compressive response was reproduced numerically by idealizing such foams to be assemblages of space-filling Kelvin cells. The onset of instability involves a long wavelength mode. It has been established by considering a fully periodic column of cells tall enough to accommodate this mode. The crushing response has been evaluated by considering finite size microsections which allow localized deformation to develop. This paper shows that the crushing stress can also be established from the local response of the fully periodic column of cells through an energy argument leading to a Maxwell-type construction.
Effects of potassium-free solutions on membrane current-voltage relations of Aplysia giant neurons.

Abstract 1. Cooling, ouabain and K + -free solutions are thought to produce inhibition of an electrogenic Na + -pump in Aplysia giant neurons. 2. Current-voltage relations of the membrane in ouabain and K + -free solution became increasingly dissimilar at membrane potentials more negative than the resting potential. 3. Ouabain produced a constant depolarization over the physiological range of membrane potentials. 4. K + -free solutions elicited a potential change that reversed sign at the normal potassium equilibrium potential, E k ⋍ −80 mV. 5. Measurements of external K + -activity (a o k ) next to the membrane indicate that a o k remains relatively constant even in K + -free solutions. 6. K + -free solutions produce membrane depolarization by K + -conductance decrease and ouabain inhibits the pump.
Echocardiography in the diagnosis of hypertrophic obstructive cardiomyopathy

Abstract The role of echocardiography in the diagnosis of hypertrophic obstructive cardiomyopathy is reviewed. Salient features include a narrowed left ventricular outflow space, the increased thickness of the interventricular septum and the systolic anterior motion of the anterior mitral leaflet. The last may be present at rest, or it may be provoked with appropriate maneuvers. When all three features are demonstrated, a diagnosis of hypertrophic obstructive cardiomyopathy can be made with confidence. In the absence of resting or provocable systolic anterior motion, a diagnosis of nonobstructive cardiomyopathy may be entertained. An additional important echocardiographic feature of hypertrophic obstructive cardiomyopathy consists of an interventricular septal to posterior wall ratio in excess of 1.5, suggesting the asymmetric distribution of hypertrophy. Inert interventricular septum, aortic valve preclosure and a reduced diastolic slope of the anterior mitral leaflet are frequently present, but not specific for the condition. When hypertrophic obstructive cardiomyopathy is associated with other unrelated diseases, the index of suspicion may be raised even in the absence of all the "classic" echo signs. In response to treatment, it has been shown that beta adrenergic blockade only rarely results in abolition of systolic anterior motion, whereas successful ventriculomyotomy and/or myectomy more consistently suppresses systolic anterior motion. Longitudinal studies with echocardiography are expected to add new light on the patterns of progression of this obscure disorder.
DNA methylation control of tissue polarity and cellular differentiation in the mammary epithelium

Alterations in gene expression accompany cell-type-specific differentiation. In complex systems where functional differentiation depends on the organization of specific cell types into highly specialized structures (tissue morphogenesis), it is not known how epigenetic mechanisms that control gene expression influence this stepwise differentiation process. We have investigated the effect of DNA methylation, a major epigenetic pathway of gene silencing, on the regulation of mammary acinar differentiation. Our in vitro model of differentiation encompasses human mammary epithelial cells that form polarized and hollow tissue structures (acini) when cultured in the presence of basement membrane components. We found that acinar morphogenesis was accompanied with chromatin remodeling, as shown by alterations in histone 4 acetylation, heterochromatin 1 protein, and histone 3 methylated on lysine 9, and with an increase in expression of MeCP2, a mediator of DNA-methylation-induced gene silencing. DNA hypomethylation induced by treatment with 5-aza-2' deoxycytidine during acinar differentiation essentially prevented the formation of apical tissue polarity. This treatment also induced the expression of CK19, a marker of cells that are in a transitional differentiation stage. These results suggest that DNA methylation is a mechanism by which mammary epithelial differentiation is coordinated both at the tissue and cellular levels.
Ultra-clean underground counting facility for low-level environmental samples

Abstract An underground counting facility with cleanroom conditions has been designed and constructed to improve detection of low-level radioisotopes in the environment. The 3.0m × 4.3m × 2.4m counting chamber is placed 14.3m below ground, has 10.2cm thick walls of pre-WWII naval armour plate, and is further shielded by a minimum of 1.2m of specular hematite. The total overburden of shielding is equivalent to 31.7m of water. Careful selection of building materials and a special air filtering system maintain a cleanroom environment with minimum contamination potential.
Relationship of length of uterus in prepubertal pigs and number of corpora lutea and fetuses at 30 days of gestation

Abstract Relationships of the length of the uterus at one reproductive stage to the length at other stages and the effect on potential litter size were determined. In Experiment 1, the length of the uterus was measured in situ at 20, 60, or 100 days of age at laparotomy with 20 gilts in each of the three age groups. Forty days after the initial measurement, the uterus was again measured in situ, gilts were ovariectomized and hysterectomized, and associations among uterine measurements at the two different stages were determined. Correlations between uterine length in situ and between uterine length and weight 40 days later were all greater than 0.75 (P
Sensory transducers of E. coli are composed of discrete structural and functional domains

Abstract The tar and tsr genes of E. coli encode functionally analogous transducer proteins that mediate two distinct classes of chemotactic response. The tap gene lies adjacent to tar , and is thought to encode another transducer protein. We present here the complete nucleotide sequence of the tar-tap region of the E. coli genome, together with a comparative analysis of the sequences of the Tar, Tap, and Tsr proteins. The proteins appear to have a simple transmembrane structure consisting of an extracytoplasmic amino-terminal domain, a membrane-spanning domain, and an intracellular carboxy-terminal domain. The carboxy-terminal domains of the three proteins possess highly homologous sequences and contain sites of methylation involved in sensory adaptation, while the amino-terminal sequences are only distantly related to one another, consistent with their serving as chemoreceptor domains that have diverged functionally.
Observation and Simulation of Storm-Induced Mixed-Layer Deepening

Abstract Two observed cases of mixed-layer (ML) deepening due to storms are analyzed and simulated. The primary goal is to learn whether the relevant scale velocity in the parameterization of wind-driven deepening is U*, the wind stress friction velocity, or δV, the magnitude of the horizontal mean velocity difference across the base of the ML. ML deepening is isolated from air–sea exchange and horizontal advection by diagnosing the entrainment tendency of ML temperature. ML deepening is found to be highly intermittent on the storm time scale. Deepening in response to a wintertime atmospheric cold front occurred as δV was accelerated during the initial rise in wind stress. Deepening abruptly ceased as wind stress began to decelerate δV, though the stress magnitude continued to increase. A similar relationship between wind stress δV and ML deepening was also observed in a summertime case and is evidence that the relevant scale velocity is δV not U*. In both cases the observed phase and extent of ML deepeni...
Measuring height without a stadiometer: empirical investigation of four height estimates among wheelchair users.

ABSTRACTObjective:This study aimed to compare four methods of measuring or estimating height among wheelchair users, to determine whether these methods result in significantly different estimates, and to determine which method is most accurate.Design:Height data were obtained for 141 wheelchair user
Empathic character analysis

Empathic Character Analysis Lawrence Josephs, Ph.D. To speak of empathic character analysis could seem like an oxymoron to those who associate the term character analysis with the approach of Wilhelm Reich (1928). Reich's seminal work could be seen as the prototype of active and confrontational approaches to the analysis of defense and resistance. Such approaches by virtue of fostering an adversarial relationship with the patient have been thought to be lacking in empathy for the patient's narcissistic vulnerability. Kohut (1984) contrasted what he called the “penetration-to-the-unconscious-via-theovercoming-of-resistances model” (p. 113) with a view of resistance as “a valuable move to safeguard the self, however weak and defensive it may be, against destruction and invasion” (p. 141). It is thought to be more empathic to treat character resistances as self-affirmative survival tactics rather than as self-defeating, selfalienating, affect-avoiding strategies that block psychological growth and express covert hostility toward others. Yet a potential liability in working with character resistances solely in terms of their self-affirmative function is to end up treating the patient with “kid gloves,” implying that the patient is so fragile or so suggestible as to be incapable of tolerating being challenged, questioned, or confronted with alternative perspectives to the patient's own subjective point of view. The analyst must achieve a dynamic balance somewhere between being “a bull in a china shop” at the one extreme and “walking on eggs” with the patient at the other extreme. Technical controversies in the field have tended to become polarized resulting in either/or approaches to treatment. What must be sustained is a dialectical approach in which the analyst need not phobically avoid being confrontational for fear of being experienced as unempathic and in which the analyst need not phobically avoid empathizing with the self-affirmative function of characterological adaptions without fear of colluding with unconsciously defensive attitudes that block the progress of the analysis. To better understand the issues at stake, a look will be taken at the theory of character analysis as it was originally developed
Strategic factors affecting foreign direct investment decisions by multi-national enterprises in Latin America

Abstract Cross-country differences in macroeconomic and institutional environments are used to explain MNE behavior, as proxied by foreign direct investments (FDIs) inflows to seven Latin American countries, namely Argentina, Brazil, Chile, Columbia, Mexico, Peru and Venezuela for the period 1988–1999. Results indicate that the institutional approach is dominant, thus supporting recent FDI research that has included statistical measures of institutional reform in their models. Since MNEs must conform to the institutional environment prevailing in the host country, managers should undertake FDI where there is minimal institutional distance between the home and the host country environments. In addition, government officials should place increased emphasis on institutional reform if their objective is to increase inward FDI in their countries. Finally, any assistance provided by non-governmental organizations, such as the IMF and the World Bank, should also emphasize institutional reform.
Sialyltransferase messenger ribonucleic acid increases in thyrotrophs of hypothyroid mice: an in situ hybridization study.

Hypothyroid patients and mice have been shown to have circulating TSH that is more highly sialylated than their euthyroid counterparts. To learn about the underlying cellular mechanisms responsible for this increased sialylation of TSH, we used in situ hybridization to examine the beta-galactoside alpha-2,6-sialyltransferase (STase) mRNA content in thyrotrophs and corticotrophs of euthyroid and hypothyroid mice. Mice were treated with or without 0.05% propylthiouracil for 1, 2, 3, 4, or 6 weeks, then pituitaries were removed, and 5-microns slices were immunocytochemically stained for TSH and ACTH. Adjacent sections were used for in situ hybridization. A 48-mer deoxynucleotide probe to rat STase and two control probes were labeled with 35S, and autoradiography was performed. There was an approximately 140% increase in STase mRNA in hypothyroid thyrotrophs compared to euthyroid thyrotrophs by the first week, with a mean increase of 170% in weeks 1-6, whereas corticotrophs exhibited no change in STase mRNA. ...
Effect of decreased dietary protein upon mammary gland growth in rats.

Nachweis, dass der gesamte DNS-Gehalt in der Brustdruse bei Tieren mit proteinfreier oder 5% iger Proteinnahrung im Vergleich zu der Kontroll-gruppe herabgesetzt ist. Wird Protein in der Nahrung um 10–20% erhoht, so bleiben DNS-Gehalt und Korperwachstum konstant.
Magnetic hysteresis in Fe-R-B powders

Abstract The hard magnetic properties of Fe-R-B powders have been examined using various magnetic techniques. High coercivities were obtained in fine powders with a particle size around 1 μ m. A domain wall pinning process is suggested for the less anisotropic, Nd-containing samples where the domain walls are pinned at the particles surface. The initial magnetization curves, field dependence of coercivity and remanence curves of thermally demagnetized samples change significantly after ac and dc demagnetization indicating a more uniform domain wall pinning process in the ac and dc demagnetized samples. A magnetization rotation reversal process is suggested for the more anisotropic, heavy rare-earth containing powders.
Modulation of Proliferation and Chemosensitivity by Procathepsin D and Its Peptides in Ovarian Cancer

Since the presence of precursors (pro-forms) of the aspartyl endoprotease, cathepsin D, appears to be linked with tumor progression, their presence was examined in sera and tumor tissues of ovarian cancer patients. The role of cathepsin D pro-forms was further assessed in the dysregulated proliferation and chemoresistance observed in advanced ovarian cancer. Cathepsin D was isolated from sera of ovarian cancer patients (n = 20) and normal volunteers (n = 11), as well as from solubilized normal ovarian epithelium (n = 8) and ovarian epithelial tumor tissue (n = 12). The specific molecular forms of cathepsin D were analyzed in these samples by Western immunoblot. Multiple circulating molecular weight forms of cathepsin D were identified in ovarian cancer patients ranging from 24 to 60 kDa, while in normal controls, a major band was observed at 34 kDa in all samples and minor bands corresponding to 27 and 48 kDa were detected in approximately half of the controls. To assess its consequences on ovarian cancer, the 52-kDa protein was immunoprecipitated from culture medium of an exponentially growing ovarian tumor cell line and was further purified by reverse-phase high-pressure liquid chromatography. Its effect on proliferation was assayed by determining cell doubling times and their chemosensitivity was measured in a standard cytotoxicity assay using cisplatin. In addition, decapeptides corresponding to the pro-portion of cathepsin D were analyzed in parallel. Procathepsin D and one decapeptide, peptide 2, as well as IGF-II (as a known positive) increased cell proliferation, with doubling times of 28.4, 28.8, and 30.3 h, respectively, versus untreated UL-1 cells (36.4 h). Procathepsin D treatment of UL-1 tumor cells significantly increased the cisplatin LD(50) (74.9 microgram/ml) over untreated (33.9 microgram/ml) as well as IGF-II-treated (38.8 microgram/ml) cells. Peptide 2 also showed a significant increase in LD(50) (69.5 microgram/ml) compared to untreated and peptide 1-treated cells (37.1 microgram/ml). There are several unique forms of cathepsin D expressed and accumulated by ovarian tumors and these forms are detectable in the sera of those with ovarian cancer. The presence of these procathepsin D can increase the proliferation of these tumor cells, while decreasing their sensitivity to chemotherapeutic agents. While procathepsin D and IGF-II both enhance proliferation, only procathepsin D (and peptide 2) appears to modulate chemosensitivity, suggesting a separate receptor or pathway for this consequence.