cssi/SciSciGPT-SciSciNet huggingface dataset:
Solute Retention in Column Liquid Chromatography. X. Determination of Solute Infinite-Dilution Activity Coefficients in Methanol, Water, and Their Mixtures, by Combined Gas-Liquid and Liquid-Liquid Chromatography

Abstract The Raoult's-law activity coefficients of 3- to 7-carbon aliphatic aldehyde, ketone, ester, and alcohol solutes at infinite dilution in methanol, water, and mixtures of the two and in polydimethylsiloxane, all at 293–308 K, have been determined for the first time by appropriate combination of GLC and LLC retention data. The latter data are reported in terms of mole fractions, while the former are given in concentration units of molality. However, interpretation of the data is difficult because of the multiplicity of the retention mechanisms. Nevertheless, the combined GLC/LLC technique, which had been applied previously only to pure solvents, is said to offer a number of advantages over static techniques for the determination of solute infinite-dilution activity coefficients with volatile solvents, especially with mixtures of solvents.
Low-latitude thermospheric neutral winds determined from AE-E measurements of the 6300-A nightglow at solar maximum

Atmosphere Explorer E (AE-E) measurements of the O(1D) 6300-A emission in the nighttime equatorial thermosphere are used to infer the height of the F2 layer peak as a function of latitude and local time. The investigation is conducted both for northern hemisphere winter solstice and for spring equinox, under solar maximum conditions. The layer heights are used to derive magnetic meridional components of the transequatorial neutral wind, in conjunction with the MSIS-86 model and previous Jicamarca incoherent scatter measurements of the zonal electric field. The AE-E wind estimates indicate a predominant summer to winter flow for the winter solstice case. Comparisons are made with the empirical horizontal wind model HWM87 and with winds generated by the thermospheric general circulation model. The model predictions and experimental results are generally in good agreement, confirming the applicability of visible airglow data to studies of the global neutral wind pattern.
Modifications of H3 and H4 during Chromatin Replication, Nucleosome Assembly, and Histone Exchange *

Histone posttranslational modifications that accompany DNA replication, nucleosome assembly, and H2A/H2B exchange were examined in human tissue culture cells. Through microsequencing analysis and chromatin immunoprecipitation, it was found that a subset of newly synthesized H3.2/H3.3 is modified by acetylation and methylation at sites that correlate with transcriptional competence. Immunoprecipitation experiments suggest that cytosolic predeposition complexes purified from cells expressing FLAG-H4 contain H3/H4 dimers, not tetramers. Studies of the deposition of newly synthesized H2A/H2B onto replicating and nonreplicating chromatin demonstrated that H2A/H2B exchange takes place in chromatin regions that contain acetylated H4; however, there is no single pattern of H4 acetylation that accompanies exchange. H2A/H2B exchange is also largely independent of the deposition of replacement histone variant, H3.3. Finally, immunoprecipitation of nucleosomes replicated in the absence of de novo nucleosome assembly showed that histone modifications do not prevent the transfer of parental histones to newly replicated DNA and thus have the potential to serve as means of epigenetic inheritance. Our experiments provide an in-depth analysis of the "histone code" associated with chromatin replication and dynamic histone exchange in human cells.
Rapid fabrication of titania nanofibers by electrospinning

This paper describes a simple and convenient procedure for fabricating polycrystalline titania nanofibers with controllable diameter and porous structures. By combining sol-gel technique and electrospinning, nanofibers made of poly(vinyl pyrrolidone) (PVP) and amorphous TiO2 were firstly obtained by electrospinning an ethanol solution containing both PVP and titanium tetraisopropoxide under appropriate high voltages. These nanofibers could be subsequently converted to anatase without changing their morphology via calcination in air at 500°C. The average diameter of these ceramic nanofibers could be controlled in the range from 20 to 200 nm by varying a number of parameters such as the voltage, the feeding rate of the precursor solution, the ratio between PVP and titanium tetraisopropoxide, and their concentrations in the alcohol solution. Titanium tetraisopropoxide could be transferred to titania nanofibers with ~100% yield by using this technique.
Possibility of incongruous interface behavior of In on GaAs(110).

Photoemission spectroscopy has been used to study the Schottky-barrier formation of In on n- and p-type GaAs(110) interfaces. Our result is different from that reported by R. R. Daniels et al. [J. Vac. Sci. Technol. A 2(2), 831 (1984)]. It is suggested that this incongruous behavior of In on GaAs(110) is due to the kinetics of interface defect formation. Various experimental details which may affect the kinetics are also discussed.
Outcomes after ruptured abdominal aortic aneurysms: the "halo effect" of trauma center designation.

Background Trauma centers have an array of services available around the clock that help reduce mortality in injured patients. Having such services available can benefit patients other than those who are injured. We set out to determine whether patients hospitalized with ruptured abdominal aortic aneurysms experience lower morbidity and mortality at regional trauma centers than at other acute care hospitals. Study design We conducted a retrospective cohort study with the exposure being care at a trauma center and outcomes either mortality or organ failure. We evaluated all patients 40 to 84 years of age with a diagnosis of a ruptured abdominal aortic aneurysm who underwent operation during 2001 in 20 US states with organized systems of trauma care. We determined the relative risk of either death or organ failure at regional trauma centers compared with nondesignated centers. Results Of 2,450 patients hospitalized for ruptured abdominal aortic aneurysm, 867 (35%) hospitalizations occurred at regional trauma centers. At trauma centers, 41.4% of patients died before hospital discharge, compared with 45.2% of patients at nondesignated hospitals (odds ratio [OR], 0.85; 95% CI, 0.71−1.02). After adjusting for payor, hospital beds, annual hospital admissions, annual inpatient operations, affiliation with a vascular surgery fellowship, and comorbid illnesses, the likelihood of death or organ failure was lower at trauma centers (OR, 0.72; 95% CI, 0.55−0.93). Conclusions Care at regional trauma centers after operative repair of ruptured abdominal aortic aneurysm is associated with improved outcomes. We postulate that these benefits reflect the ability of both vascular and general surgeons to immediately mobilize resources for care of the patient requiring urgent operative intervention. The beneficial effects of trauma center designation might extend beyond caring for the critically injured.
Molecular basis of mucopolysaccharidosis type IIIB in emu (Dromaius novaehollandiae): an avian model of Sanfilippo syndrome type B.

Abstract Sanfilippo syndrome type B, or mucopolysaccharidosis (MPS) IIIB, is an autosomal recessive disease caused by a deficiency of lysosomal α- N -acetylglucosaminidase (NAGLU). In Dromaius novaehollandiae (emu), a progressive neurologic disease was recently discovered, which was characterized by NAGLU deficiency and heparan sulfate accumulation. To define the molecular basis, the sequences of the normal emu NAGLU cDNA and gene were determined by PCR-based approaches using primers for highly conserved regions of evolutionarily distant NAGLU homologues. It was observed that the emu NAGLU gene is structurally similar to that of human and mouse, but the introns are considerably shorter. The cDNA had an open reading frame (ORF) of 2259 bp. The deduced amino acid sequence is estimated to share 64% identity with human, 63% with mouse, 41% with Drosophila, 39% with tobacco, and 35% with the Caenorhabditis elegans enzyme. Three normal and two affected emus were studied for nucleotide sequence covering the entire coding region and exon–intron boundaries. Unlike the human gene, emu NAGLU appeared to be highly polymorphic: 19 variations were found in the coding region alone. The two affected emus were found to be homozygous for a 2-bp deletion, 1098-1099delGG, in exon 6. The resulting frameshift predicts a longer ORF of 2370 bp encoding a polypeptide with 37 additional amino acids and 387 altered amino acids. The availability of mutation screening in emus now permits early detection of MPS IIIB in breeding stocks and is an important step in characterizing this unique, naturally occurring avian model for the development of gene transfer studies.
An investigation into the effects of ethnicity and immigration on self-employment

This paper examines self-employment across industries and states in the U.S. It attempts to determine whether self-employment is due more to pull or push factors and whether one or the other model fits some industries better or fits some states better. The 1990 Public Use Microdata Samples from the U.S. Census Bureau are used in the empirical analysis. It is found that self-employment rates differ considerably across ethnic groups, and that the rate of self-employment tends to be higher for immigrants. This paper also finds that increasing urbanization tends to reduce self-employment rates while the shift from manufacturing to service industries tends to increase self-employment rates.
Pinna Temperature in Exercising Jackrabbits, Lepus californicus

Pinna surface temperatures of Lepus californicus were examined radiographically before and after forced exercise (e.g., running at about 6 km/h for 6 min) in an outdoor enclosure. Air temperatures were from −1.6 to +19.4°C, and radiant sky temperatures were from —27 to +22°C. In resting animals, average pinna surface temperature was only 0.3 to 2.5°C above air temperature, and pinna arteries were not evident radiographically. Immediately after exercise, average pinna temperature was often near 30°C and pinna arteries were evident, indicating vasodilation. Cooling of the pinnae to resting temperatures after exercise generally took 15 to 25 min. Calculations indicate that the pinnae can dissipate most of the excess metabolic heat generated during the exercise examined, and it is suggested that the role of the pinnae as dissipators of exercise-induced heat loads should be considered as a factor in the evolution of pinna size.
The Team Multiple Errands Test: A Platform to Evaluate Distributed Teams

Teams have the ability to achieve goals that are unobtainable by individuals alone. However, there is little agreement on a standard model for researching the performance of distributed teams. Initial pilot results suggest that the Multiple Errands Test (MET), when adapted to a team in a virtual environment, is a platform for evaluating the impact of feedback characteristics. To demonstrate the potential of the Team MET as a platform for future team research in the broader CSCW community, an example study is described in which team members are given feedback in one of four conditions: individual private, team private, individual public, and team public.
TESTING THE LEAP-FROG HYPOTHESIS: The impact of existing infrastructure and telecommunications policy on the global digital divide

This paper tests the ‘leap-frog’ hypothesis by modeling the impact of existing telecommunications infrastructure, controlling for economic, political and demographic factors, on changes in information communication technology (ICT) access for over 200 countries between 1995 and 2005. This study has significantly greater coverage than previous research, in terms of both time frame and country cases. First, the analysis demonstrates that in the first decade of the information society successful leap-frog countries are few and far between. Second, the relative distribution of personal computers, internet hosts and secure servers among the nations of the world has barely improved over the last decade. Third, contrary to received wisdom, most of the countries that might qualify as successful leap-frog countries are actually among the wealthiest in the world. Finally, while policy reform in the telecommunications sector can sometimes speed the diffusion of digital communication tools, the record of market refor...
Downlink “feedback” channel design for LTE femtocell inter-cell interference mitigation

A downlink “feedback” channel for an algorithm of LTE Femtocell Inter-cell Interference mitigation is designed in this paper. Specifically, in the receiver, a blind-detection method is established in order to correctly decode the signal transmitted. The simulation result shows that the designed channel would have low block error ratio (BLER). A simulation was implemented on DSP, and results also show that the designed downlink “feedback” channel is effective as the inter-cell interference (ICI) mitigation algorithm.
Stimulation of Human Natural Killer Cytotoxicity and Protection of Mice from Infection Due to Herpes Simplex Virus by Recombinant Human Leukocyte Interferon

Destruction of virus-infected cells in the absence of antibody (natural killer cytotoxicity [NKC]) has been correlated with resistance to infection due to herpes simplex virus (HSV). Two preparations of human leukocyte interferon produced by recombinant DNA bacteria--IFLrA and IFLrD--were demonstrated to increase NKC in a dose-dependent fashion in vitro. IFLrA was more potent than was IFLrD in this assay. When administered intraperitoneally in combination with human leukocytes to one-week-old mice, IFLrA and IFLrD significantly increased survival (to 47.6% [P less than 0.01] and 23.8% [P less than 0.05], respectively) after an otherwise uniformly lethal challenge of HSV. Differences between interferon immunostimulating activities at similar antiviral concentrations may be important in vivo in animals and in clinical settings.
Suppression of maternal virus load with zidovudine, didanosine, and indinavir combination therapy prevents mother-to-fetus HIV transmission in macaques.

Recently, we developed a maternal-fetal macaque model using a highly pathogenic HIV-2 strain, HIV-2 287 , to study the time course of HIV transmission in utero. Most pregnant macaques (Macaca nemestrina) infected with HIV-2 287 (10-10 3 infective doses) transmitted HIV to their fetuses, as verified by positive identification of virus-infected mononuclear cells and free viral RNA in fetal blood. To determine whether an antiretroviral drug combination therapy composed of two dideoxynucleosides, azidothymidine (15 mg/kg) and dideoxyinosine (15 mg/kg), and a protease inhibitor, indinavir (25 mg/kg), could completely inhibit mother-to-fetus HIV transmission, we administered these drugs orally through gastric catheters to five pregnant macaques infected with 10 infective doses of HIV-2 287 , Beginning 30 minutes after HIV inoculation, the dams were given the combination antiviral therapy three times daily until delivery by cesarean section. Drug treatment reduced the maternal virus load to a minimally detectable level but did not prevent primary HIV-2 287 infection. All fetal and infant blood samples were virus negative by internally controlled RNA polymerase chain reaction (QC-RNA-PCR) and virus coculture assays. Fetal and infant CD4 + T-cell levels remained normal throughout the experiment. These findings strongly suggest that combination chemotherapy with azidothymidine, dideoxyinosine, and indinavir can suppress maternal viral load enough to prevent mother-to-fetus transmission of HIV.
Laser-induced swelling of transparent glasses

Abstract We describe the process of forming bumps on the surface of transparent glasses such as display glasses with moderate thermal expansion ∼3.2 × 10−6 K−1 and high coefficient of thermal expansion (CTE) glasses, e.g. soda-lime glasses with CTE ∼9 × 10−6 K−1 using high-power ultra-violet (UV) lasers at a wavelength where glass is transparent. We characterize the effect with optical dynamic measurements. The process relies on increased glass absorption from color-center generation and leads to glass swelling with bumps formation. The bump height may constitute more than 10% of the thickness of the glass sample. The required exposure time is relatively short ∼1 s, and depends on the glass properties, laser power, its repetition rate, and focusing conditions. A brief review of the potential applications for these bumps is provided.
Stimulatory and persistent effect of acute hyperoxia on respiratory gas exchange of the chick embryo

Abstract The hypothesis that oxygen availability limits growth of the normal chick embryo late in development predicts that an increase in oxygen availability would accelerate the rate of growth and, therefore, metabolism. We tested the prediction concerning metabolism by comparing the oxygen consumption (V O 2 ) and carbon dioxide production (V CO2 ) of 14–18 day embryos acutely exposed to either 60% or 100% O 2 with those of normoxic (21% O 2 ) controls. Two hours of hyperoxia produced increases in both V O 2 and V CO 2 ; however, repeated measurements over time in normoxia also demonstrated a significant increase in gas exchange, presumably due to normal growth of the embryos. After correcting for the increase in V O 2 due to growth, there was no effect of 60% O 2 on day 14. Thereafter the stimulatory effect of 60% O 2 increased gradually, reaching 6.1% on day 18. V CO 2 was 4 to 6% higher in embryos acutely exposed to 60% O 2 than in normoxic controls throughout the observation period, although the difference was significant only to day 18. The V O 2 of embryos acutely exposed to 100% O 2 was not significantly different from that observed in 60% O 2 , and was still significantly elevated 3 h after the eggs were returned to 21% O 2 . We conclude that acute hyperoxia late in incubation elicits an increased in embryonic V O 2 and V CO 2 , with little or no effect on the respiratory exchange ratio, and that the stimulation of gas exchange by 100% O 2 persists after the embryo is returned to normoxic conditions. These findings support the hypothesis that oxygen availability limits growth and metabolism of the normoxic chick embryo late in development.
Mutational analysis of the 5' leader region of simian foamy virus type 1.

Abstract The sequence within the 5′ untranslated region of the retroviral genome contains important cis elements for many steps in viral replication. There is limited information available on the role of this region in foamy virus replication. Similar to other retroviruses, the 5′ untranslated region of foamy viruses predicts extensive RNA secondary structure. Serial mutations that could change parts of the predicted secondary structure were introduced in the 5′ leader sequence including the R-U5 region of simian foamy virus type 1 (SFV-1) to investigate their role in virus genome packaging and virus replication. Point mutations in the R-U5 regions at nucleotide positions 7–12 (I), 241–243 (B), and 256–257 (D) had no effect on virus replication. Base substitution mutation at positions 193–195 (C), however, severely impaired virus replication. Deletion of sequences in the leader region, between the primer-binding site and the gag gene, at positions 364–399 (d1), 397–435 (d2), or 364–435 (d3), which included sequences for RNA genome dimerization, also blocked SFV-1 replication. Interestingly, none of these mutations affected genome packaging or the synthesis of viral transcripts, suggesting that a step(s) of virus replication following packaging is affected. The region between the primer-binding site and the gag gene, therefore, is not essential for foamy virus genome packaging. Furthermore, the cis -acting elements for genome dimerization and packaging appear to be localized in separate regions for foamy viruses.
Ein Beitrag zum Problem der Membranelektrode. Die Bestimmung des Äquivalenzpunktes mit Hilfe des Membranpotentials I. Fällungstitrationen von Silbersalzen.

Das feinporige Membransystem von Aluminiumoxyddeckschichten wurde als Membranelektrode bei Fallungstitrationen von Silbersalzen verwendet. Der Aquivalenzpunkt wird bei geeigneter Wahl der Elektrolytsysteme durch einen relativ grossen Potentialsprung angezeigt.
Differences in age, laterality, and Steinberg stage at initial presentation in patients with steroid-induced, alcohol-induced, and idiopathic femoral head osteonecrosis.

Comparisons between treatments and studies with regard to femoral head osteonecrosis (ON) are difficult because the demographic characteristics of the patients composing the samples vary greatly. The purpose of this investigation was to determine whether ON initiation and progression were specific for a causative agent. A group of 172 patients (245 hips) was subdivided by causative agent. Patients with alcohol-induced ON were significantly older (average age, 49 years; P = .0001), were men (97%), and presented with collapsed femoral heads (90%). Patients with steroid-induced ON averaged 39 years of age, 49% had bilateral disease, and 62% presented with a collapsed femoral head. Patients with idiopathic ON averaged 40 years of age, 35% had bilateral disease, and 55% presented with a collapsed femoral head. Given the different distributions of ON risk factors at initial presentation, it is likely that successful or unsuccessful outcomes may depend most on the sample receiving the intervention. We therefore recommend stratification of patients by causative agent, Steinberg stage at initial presentation, and presence of unilateral or bilateral disease to help clarify the effects of the various treatments for ON of the femoral head.
Interaction of folylpolyglutamates with enzymes in one-carbon metabolism

Of all the coenzymes, tetrahydrofolate exhibits the most structural diversity. The relationship of these structural forms to physiological function is under intense study by numerous research groups. In textbooks, tetrahydrofolate (tetrahydropteroylmonoglutamate) is shown as the coenzyme of one-carbon metabolism, but it has been known for several decades that the physiologically active forms of the coenzyme contain from 4 to 7 glutamyl residues linked by amide bonds through the gamma-carboxyl group. These glutamyl residues do not serve a direct function in transferring the one-carbon group. The tetrahydrofolylpolyglutamates were originally thought to be simply storage forms of the coenzyme, but studies now show that the polyglutamate chain of the coenzyme affects the transport properties of the coenzyme, alters the kinetic properties of many enzymes in one-carbon metabolism, and results in channeling of the coenzyme between several enzymes. In general, the dissociation constants of this group of enzymes for the tetrahydrofolylpolyglutamates are very low, in the 0.1 to 1 microM range. The concentration of the coenzyme in the cell appears to be similar to the concentration of folate-utilizing enzymes, suggesting that the concentration of unbound coenzyme in the cell may be very low. Several of the enzymes in one-carbon metabolism are either multifunctional proteins or multienzyme complexes. An active area of research is to determine if there is a functional relationship between these multifunctional enzymes and the polyglutamate portion of the coenzyme.
Constrained hypothesis testing and the Cramér-Rao bound

The classical Wald and Rao test statistics are asymptotically equivalent to the generalized likelihood ratio test statistics, while not requiring parameter estimation under both hypotheses, and so they provide lower complexity test statistics. In this paper we develop corresponding variations of the Wald and Rao test for nested hypothesis testing under parameter constraints. The resulting tests incorporate the constrained Cramer-Rao bound formulation from Stoica and Ng, and unify some asymptotic hypothesis testing results. Examples will illustrate key ideas and test performance.
Genetic and Physiological Evidence Concerning the Development of Chemically Sensitive Voltage- Dependent Ionophores in L6 Cells

SUMMARY The electrophysiological properties of a tissue culture muscle line, L6, and a K+ resistant mutant (MKI) derived from LG were determined to elucidate certain aspects of membrane differentiation and function. MKI was selected as a clone of myoblasts resistant to the toxic effects of 55 mM K+. The resting potentials of LG and MKI myoblasts and myotubes were K+ dependent and equal. The amplitudes of the action potentials were equal in normal medium, but 27.7 mM K+ interfered with or eliminated the ability of L6 myotubes to produce action potentials. MK1 myotubes produced nearly normal action potentials under these conditions. Thus, the K+ resistant myoblasts differentiate into myotubes which have an action potential generating mechanism much less sensitive to K+ than the normal mechanism. Also, both d -tubocurarine and a-bungarotoxin enhance the amplitude of the action potentials produced by L6 myotubes in the presence of 27.7 mM K+; these compounds do not enhance the amplitude of the action potentials produced by MKI myotubes under the same conditions. It is proposed that as a consequence of differentiation a type of ionophore present in myoblasts becomes a voltage-dependent ionophore in myotubes. Furthermore, these voltage-dependent ionophores can be chemically sensitive.
Summarizing technical support documents for search: expert and user studies

One factor that may affect whether users of technical support Web sites can rapidly find information relevant to their needs is the quality of the summary of documents returned as the result of search queries. This paper reports on two studies that were part of an effort to create high-quality machine-generated summaries for the presentation of search results for technical support documents. The initial study asked experts to compose document summaries. The results of the first study were used to guide the development of heuristics for generating programmatic summaries that were tested in the second study, which was a user evaluation that compared the effectiveness of four types of document summaries for search purposes: programmatic summaries based on selective sentence extraction using knowledge of the semantic structure of documents, a term-hits-in-context (THIC) summary, the current summaries on the company's live site, and document titles alone. This comparison sought to determine the techniques most likely to help users find information, hence increasing customer goal attainment and satisfaction. The implications of our results for summarizing technical support documents for search are discussed.
Blame Analysis: Accounting for the Behavior of Protected Groups.

When a group is not doing as well as other groups on some dimension, group members and sympathizers give accounts that attempt to minimize the group’s blame for its predicament. These accounts reflect concerns about prejudice, as well as policy concerns. This approach to social science may be called “blame analysis,” because it evaluates theories according to the extent to which they blame protected groups. Blame analysis treats cause and blame as the same, and rejects theoretical arguments that posit any causal role for the protected group because they “blame the victim.” As a result, discussions of proximate causes and mediating variables are avoided in explanations of outcomes for these groups. The author argues that this approach violates scientific principles and discourages the investigation of important issues.
Enzyme-Doped Graphene Nanosheets for Enhanced Glucose Biosensing

In this work, we report the enhanced performance of polypyrrole−graphene−glucose oxidase based enzymatic biosensors employed for in vitro electrochemical glucose detection. Initially, graphene nanosheets were chemically synthesized and surface morphologies were characterized by several physical methods. Following this, graphene nanosheets were covalently conjugated to an enzyme model glucose oxidase (GOD). The presence of various reactive functionalities such as ketonic, quinonic, and carboxylic functional groups on the edge plane of graphene easily binds with the free amine terminals of the glucose oxidase to result in a strong covalent amide linkage. Further, this covalent conjugation of the enzyme to graphene was confirmed by FT-IR measurements. Following this, the surface of a glassy carbon electrode was modified by polypyrrole. Later, the conjugated graphene−GOD were then immobilized onto the glassy carbon electrode surface already modified with polypyrrole (Ppy) and the entire assembly was employed ...
Demystifying the Witsenhausen Counterexample [Ask the Experts]

Q. In my graduate-level controls course, the instructor mentioned the “Witsenhausen counterexample,” which seems to have something to do with decentralized control and communication. But I must confess that I did not understand what was going on or why it was important. Could someone at IEEE Control Systems Magazine provide a clear and simple explanation? Thanks.
The Benefits of Exercise for Individuals with Arthritis: An Integrative Review with Meta-Analysis

(1) While individuals with osteoarthritis (OA) and rheumatoid arthritis (RA) are frequently seen by caregivers in the health care system, some confusion still exists when it comes to making recommendations related to exercise and activity. While a number of research studies have supported the safety and benefits of moderate to rather intense exercise for both of these conditions, many practitioners continue to recommend limited activity for these populations. This review of the research literature and meta-analysis seeks to explicate for the practitioner the “state-of-the-art” in making exercise and activity recommendations to their clients with OA and RA.
Modification of membrane physical properties, biological response and insulin binding in Friend cells by low serum concentration

The effect of low serum concentration on plasma membrane fluidity and lipid composition, differentiation and insulin binding was investigated in three Friend erythroleukemia clones. Both FLC (clones No. 745) and F(+) (Ostertag F4N) Friend erythroleukemia cells can be induced to differentiate and to produce hemoglobin when exposed to DMSO. Clone R(3) (Ostertag F4-D5-1) is a DMSO-resistant clone when grown under normal conditions (15% serum) but could undergo differentiation with accumulation of protoporphyrin IX upon induction with DMSO when grown in low serum concentration (2.5% serum). Electron spin resonance measurements of the order parameters (S) and S(T parallel) demonstrate that R(3) has a more fluid plasma membrane than the FLC and F(+). The order parameters of the outer hyperfine splittings S(T parallel) at 37 degrees C are 0.60 +/- 0.009, 0.62 +/- 0.008 and 0.64 +/- 0.009 for R(3), F(+) and FLC, respectively. We have used the insulin receptors as a model for a polypeptide hormone receptor associated with the plasma membrane of the Friend clones. Insulin binding studies demonstrated that the receptor of R(3) had a decreased affinity for insulin manifest as a 10-fold increase in the amount of insulin required to compete for half of the tracer binding (18 nM for R(3) vs. 2 nM for FLC and F(+)). Computer-fit Scatchard plot analysis by the negative cooperativity model reveal that R(3) possessed a similar number of sites/cell (about 70,000) as the FLC or F(+) cells, with similar high and low affinities. Growing the DMSO-resistant clone R(3) in low serum concentration caused a decrease in receptor number by 35%, and an increase in receptor affinity to that seen with the differentiable clones. Thus, the abnormal properties of the plasma membrane and insulin receptor of the DMSO-resistant clone in our earlier report (Simon et al. (1984) Biochim. Biophys. Acta 803, 39-47) were partially reversed by growing the cells in a low serum concentration, restoring the cellular response to the differentiation agent.
Classification and pose estimation of objects using nonlinear features

A new nonlinear feature extraction method called the maximum representation and discrimination feature (MRDF) method is presented for extraction of features from input image data. It implements transformations similar to the Sigma-Pi neural network. However, the weights of the MRDF are obtained in closed form, and offer advantages compared to nonlinear neural network implementations. The features extracted are useful for both object discrimination (classification) and object representation (pose estimation). We show its use in estimating the class and pose of images of real objects and rendered solid CAD models of machine parts from single views using a feature-space trajectory (FST) neural network classifier. We show more accurate classification and pose estimation results than are achieved by standard principal component analysis (PCA) and Fukunaga-Koontz (FK) feature extraction methods.
Mechanical noise enhances signal transmission in the bullfrog sacculus.

Noise has been commonly thought to degrade the performance of sensory systems. However, it is now clear that the detection and transmission of weak signals in sensory systems can be enhanced by noise via stochastic resonance (SR). In hair cells, the quality of mechanoelectrical transduction is enhanced up to twofold by nanometer level mechanical noise acting on the hair bundle. We wanted to know whether these gains could be preserved, perhaps even enhanced, as information flows across hair cell synapses, and into the stream of action potentials that in the frog conveys acoustic information to the central nervous system. To approach this question, we studied the effects of noise on the signal-to-noise ratio (SNR) of the 8th nerve’s response to small mechanical stimuli directly applied to the amphibian sacculus. We found that ~2.5 nm of mechanical noise enhanced the response of the saccular nerve up to fourfold, suggesting that the positive effects of low-amplitude mechanical noise result in improved transmission of acoustic information.
Climate variability and change in the drylands of Western North America

Abstract We argue that it is important to expand the consideration of climate in the context of provision of ecosystem services in drylands. In addition to climate change, it is necessary to include climate variability on timescales relevant to human and ecological considerations, namely interannual to decadal and multidecadal. The period of global instrumental record (about a century and a half long at the very most) is neither an adequate nor an unbiased sample of the range and character of natural climate variability that might be expected with the climate system configured as it is now. We base this on evidence from W. N. America, where there has recently been a major multi-year drought, of a scale and intensity that has occurred several times in the last 2000 years, and on attempts to provide explanations of these phenomena based on physical climatology. Ensembles of runs of forced climate system models suggest the next 50 years will bring much more extensive and intense drought in the continental interior of North America. The trajectory followed by the supply of ecosystem services will be contingent not only on the genotypes available and the antecedent soil, economic and social conditions but also on climate variability and change. The critical features of climate on which patterns of plant growth and water supply depend may vary sharply during and between human generations, resulting in very different experiences and hence, expectations.
Translocation of the retina for management of subfoveal choroidal neovascularization II : A preliminary report in humans

Abstract Purpose: To report a surgical method for translocation of the foveal retina in eyes with subfoveal choroidal neovascularization. Methods: In three eyes of three patients, a crescent-shaped, partial-thickness scleral resection was performed near the equator at either the superotemporal or the inferotemporal quadrant. A near-total retinal detachment was created; then the edges of the resected sclera were sutured, causing shortening of the sclera with subsequent reattachment of the retina, resulting in translocation of the fovea to an area overlying nonfoveal retinal pigment epithelium and choroid. Results: In three eyes of three patients, the fovea was surgically translocated to overlie retinal pigment epithelium that preoperatively was not underlying the fovea. In two patients, laser photocoagulation was applied to the choroidal neovascularization that, after translocation of the fovea, was no longer subfoveal, so that the photocoagulation was not associated with immediate visual loss. After a follow-up of 4 to 6 months, the visual acuity had improved in all patients (from 20/126 preoperatively to 20/70 in one patient, from 20/200 preoperatively to 20/70 in the second, and from 20/160 to 20/30 in the third). The patients noted distortion or tilting of the images, which improved over time. Conclusions: Limited foveal translocation may offer a therapeutic modality to preserve or improve vision in cases of subfoveal choroidal neovascularization. Additional follow-up is needed to assess the impact of potential complications associated with the surgical procedure, such as retinal detachment, proliferative vitreoretinopathy, and cataract, as well as the possibility of recurrent choroidal neovascularization.
Comprehensive investigation of ectoparasite community and abundance across life history stages of avian host

Fitness consequences of ectoparasitism are expressed over the lifetime of their hosts in relation to variation in composition and abundance of the entire ectoparasite community and across all host life history stages. However, most empirical studies have focused on parasite species-specific effects and only during some life history stages. We conducted a systematic, year-long survey of an ectoparasite community in a wild population of house finches Carpodacus mexicanus Muller in south-western Arizona, with a specific focus on ecological and behavioral correlates of ectoparasite prevalence and abundance. We investigated five ectoparasite species: two feather mite genera – both novel for house finches –Strelkoviacarus (Analgidae) and Dermoglyphus (Dermoglyphidae), the nest mite Pellonyssus reedi (Macronyssidae), and the lice Menacanthus alaudae (Menoponidae) and Ricinus microcephalus (Ricinidae). Mite P. reedi and louse Menacanthus alaudae abundance peaked during host breeding season, especially in older birds, whereas feather mite abundance peaked during molt. Overall, breeding birds had more P. reedi than non-breeders, molting males had greater abundance of feather mites than molting females and non-molting males, and young males had more feather mites than older males. We discuss these results in relation to natural history of ectoparasites under study and suggest that ectoparasites might synchronize their life cycles to those of their hosts. Pronounced differences in relative abundance of ectoparasite species among host's life history stages have important implications for evolution of parasite-specific host defenses.
Clinical syndromes associated with disorders of renal tubular chloride transport: Excess and deficiency of a circulating factor?

Abstract Two contrasting patients are described, one with pseudo-Bartter's syndrome induced by frusemide abuse and the other a case of hyporeninaemic hypoaldosteronism. The clinical and biochemical features of these two conditions are the opposite of each other and, in the first patient, the effects of frusemide were antagonised by treatment with indomethacin while in the second frusemide itself corrected the syndrome. The decreased pressor sensitivity to infused angiotensin II seen in the patient with pseudo-Bartter's syndrome was corrected with indomethacin and the enhanced pressor sensitivity seen in hyporeninaemic hypoaldosteronism was reversed with frusemide. Frusemide, an agent which blocks chloride transport at the ascending limb of Henle's loop, was respectively thus the cause and the cure of these conditions. On the basis of this the suggestion is made that Bartter's syndrome and hyporeninaemic hypoaldosteronism represent respectively an excess and a deficiency of a circulating factor similar to frusemide capable of blocking renal tubular chloride transport.
Law-governed interaction: a coordination and control mechanism for heterogeneous distributed systems

Software technology is undergoing a transition form monolithic systems, constructed according to a single overall design, into conglomerates of semiautonomous, heterogeneous, and independently designed subsystems, constructed and managed by different organizations, with little, if any, knowledge of each other. Among the problems inherent in such conglomerates, none is more serious than the difficulty to control the activities of the disparate agents operating in it, and the difficulty for such agents to coordinate their activities with each other. We argue that the nature of coordination and control required for such systems calls for the following principles to be satisfied: (1) coordination policies need to be enforced: (2) the enforcement needs to be decentralized; and (3) coordination policies need to be formulated explicitly—rather than being implicit in the code of the agents involved—and they should be enforced by means of a generic, broad spectrum mechanism; and (4) it should be possible to deploy and enforce a policy incrementally, without exacting any cost from agents and activities not subject to it. We describe a mechansim called law-governed interaction (LGI), currently implemented by the Moses toolkit, which has been designed to satisfy these principles. We show that LGI is at least as general as a conventional centralized coordination mechanism (CCM), and that it is more scalable, and generally more efficient, then CCM.
Brand Portfolio, Corporate Image, and Reputation: Managing Brand Deletions

Brand portfolio management addresses, among other issues, the interrelated questions of what brands to add, retain, or delete. A small number of brands in a firm’s brand portfolio can often have a disproportionately large positive or negative impact on its image and reputation and the responses of stakeholders. Brand deletions can be critical from the standpoint of a firm being able to free up resources to redeploy toward enhancing the competitive standing and financial performance of brands in its portfolio with the greatest potential to positively affect its image and reputation. Against this backdrop, the authors focus on the organizational and environmental drivers of brand deletion propensity, the predisposition of a firm to delete a particular brand from its brand portfolio. The authors propose a conceptual model delineating the drivers of brand deletion propensity and suggest directions for future research, including the related concept of brand deletion intensity.
Nitrate-containing beetroot enhances myocyte metabolism and mitochondrial content

Beetroot (甜菜 tian cai) juice consumption is of current interest for improving aerobic performance by acting as a vasodilator and possibly through alterations in skeletal muscle metabolism and physiology. This work explored the effects of a commercially available beetroot supplement on metabolism, gene expression, and mitochondrial content in cultured myocytes. C2C12 myocytes were treated with various concentrations of the beetroot supplement for various durations. Glycolytic metabolism and oxidative metabolism were quantified via measurement of extracellular acidification and oxygen consumption, respectively. Metabolic gene expression was measured using quantitative reverse transcription–polymerase chain reaction, and mitochondrial content was assessed with flow cytometry and confocal microscopy. Cells treated with beetroot exhibited significantly increased oxidative metabolism, concurrently with elevated metabolic gene expression including peroxisome proliferator-activated receptor gamma coactivator-1 alpha, nuclear respiratory factor 1, mitochondrial transcription factor A, and glucose transporter 4, leading to increased mitochondrial biogenesis. Our data show that treatment with a beetroot supplement increases basal oxidative metabolism. Our observations are also among the first to demonstrate that beetroot extract is an inducer of metabolic gene expression and mitochondrial biogenesis. These observations support the need for further investigation into the therapeutic and pharmacological effects of nitrate-containing supplements for health and athletic benefits.
A brief survey of extrapolation quadrature

This is a short precis of a presentation on some of the recent advances in the area of extrapolation quadrature given at David Elliott's 65th birthday conference in Hobart in February 1997. Since the dawn of mathematics, historians and others have found many isolated instances of extrapolation being used in numerical calculation. However, the first serious proponent seems to have been Richardson (1923). His technique, also known as the 'deferred approach to the limit,' can be applied to the numerical evaluation of any quantity L, which can be defined as a limit as h approaches zero of an approximation L(h) when this L(h) has an expansion of the form L(h) = L + a{sub 1}h + a{sub 2}h{sup 2} + {hor_ellipsis} + a{sub r}h{sup r} + O(h{sup r+1}). In other words, the discretization error L(h) - L has a power series expansion in the parameter (usually a step length) h. Richardson suggested his technique particularly for large calculations. Richardson's technique comprised evaluating several relatively poor approximations based on different moderate values of h, and then extrapolating these values to obtain an approximately for L(0). This was proposed as an alternative to using a single, much smaller, value of h. Duringmore » the subsequent 25 years, Richardson's approach was consistently ignored or misunderstood in environments where the analysis was available and, where in retrospect, the method would have been powerful, But, in the second half of the twentieth century, Richardson's idea has been widely exploited in several numerical areas. Many expansions that can be used for extrapolation have been discovered, some of which are displayed here. In the discipline of numerical quadrature, this body of theory is sometimes referred to as extrapolation quadrature. This theory has several aspects. The first, dealt with in this talk, is the establishment of the expansion. But also of significant importance are equations relating to is use: in particular, selecting which values of h to use, organizing such a calculation, avoiding amplification of roundoff and other calculational error, and comparing other methods for handling the same problem. This talk was devoted exclusively to the first problem, the discovery of suitable asymptotic expansions, and was restricted to numerical quadrature.« less