cssi/SciSciGPT-SciSciNet huggingface dataset:
Secure and privacy-preserving data services in the cloud: a data centric view

Cloud computing becomes a successful paradigm for data computing and storage. Increasing concerns about data security and privacy in the cloud, however, have emerged. Ensuring security and privacy for data management and query processing in the cloud is critical for better and broader uses of the cloud. This tutorial covers some common cloud security and privacy threats and the relevant research, while focusing on the works that protect data confidentiality and query access privacy for sensitive data being stored and queried in the cloud. We provide a comprehensive study of state-of-the-art schemes and techniques for protecting data confidentiality and access privacy, which make different tradeoffs in the multidimensional space of security, privacy, functionality and performance.
Repair and strengthening of New York's infrastructure

As with many other established urban areas in the world, the greater part of a structural engineer’s job deals with repairing and rehabilitating an ageing, yet vital infrastructure, as opposed to designing new structures. Universities, at the undergraduate and graduate levels, prepare structural engineers better for the latter type of design (new structures) than the former (repair of structures). Thus, a lack of understanding exists regarding the deterioration of structures among most graduating engineers in the United States. They may not be aware that the structures they design will eventually fail, not from the variety of loadings for which they have mastered the ability to analyze and design structures, but from deterioration. Greater understanding of the deterioration of structures will lead to improved design of new structures and more effective repair and strengthening of vital existing structures that have deteriorated.
Measurements and calculations of the gamma response of neutron scintillators

Abstract By adapting routines from existing simulation programs for the interaction of neutrons and gammas with organic scintillators, a code has been produced to calculate the response of multi-element detectors to neutrons below 200 MeV and gammas below 10 MeV. The approach for the gamma calculations is similar to the macroscopic model used for neutron interactions. To test the approximations concerning gamma multiple-scattering and electron range-energy relations, measurements were made for the response of plastic scintillators to gammas at energies up to 1.3 MeV. The measurements focus on count rates and light-output distributions, and their analysis includes discussions of energy-to-light conversion and detector resolution. All measurements and calculations are in good agreement. The conclusions are discussed in terms of calculations of detection efficiencies for neutrons at energies of 1–200 MeV.
An optimal dual-size vial system for the cost-effective usage of Adenoscan.

Background Adenoscan (Fujisawa USA, Inc., Deerfield, Ill.) has been initially packaged in a 30 ml glass vial for single use only because it contains no preservative. This restricted usage has generated considerable waste and high cost for the patient. Although the new 20 ml vial of Adenoscan provides some reduction in waste, the savings offered by the 20 ml and 30 ml vial system is still not optimal. The purpose of this study was to investigate an optimal dual-size vial system that would provide limited amounts of waste while maintaining its practicality to satisfy different patient populations.
Maize pyruvate decarboxylase mRNA is induced anaerobically

A cDNA was identified using an oligonucleotide designed by comparing the sequences of bacterial and yeast pyruvate decarboxylase. The sequence of the cDNA identified by the oligonucleotide contained an open reading frame that encoded a protein of 65 kDa that was similar in sequence to bacterial and yeast pyruvate decarboxylase. This protein was selectively precipitated by an antiserum specific for maize PDC. Northern-blot analysis shows that PDC mRNA is anaerobically induced. Southern-blot analysis of maize genomic DNA indicated that the maize PDC gene has a single or low copy number.
The polynomial expansion method for boundary value problems of transport in rarefied gases

The principles of rarefied gas dynamics are finding application in many areas of practical interest ranging from aerosol science to micro–fabrication to vacuum and space applications. Many methods have become available for solving the Boltzmann equation which is the complicated integro–differential equation that describes the distribution of the gas molecules and forms the basis for the field of rarefied gas dynamics. Moments methods are among the most popular of these solution techniques due to their relative simplicity and overall versatility. In the half–range moment method of solving boundary value problems based on the Boltzmann equation, difficult bracket integrals are encountered. We discuss here a simplification of such integrals specific to the spherical geometry and applicable for arbitrary values of the Knudsen number. A polynomial expansion in velocity space is used to represent the discontinuous factor in these integrals. The accuracy of the method is verified by a comparison of the analytical results with available numerical results.
The twinned crystal structure of μ‐2,2′‐bipyrimidine‐1κ2N1,N1′:2κ2N3,N3′‐bis­{tris­[4,4,4‐trifluoro‐1‐(2‐thienyl)butane‐1,3‐dionato‐κ2O,O′]terbium(III)} ethyl acetate solvate

The title compound, [Tb2(C24H12F9O6S3)2(C8H6N4)]·C4H8O2, has two terbium(III) centers bridged by the polyazine ligand 2,2′-bipyrimidine (bpm), which is distorted from planarity by 7.0 (2)°. The terminal ligand 4,4,4-trifluoro-1-(2-thienyl)­butane-1,3-dione (tta) is bidentate, coordinating through the two O atoms, while the bridging ligand is bis-bidentate, coordinating through four equivalent N atoms. Both the complex and the ethyl acetate solvent mol­ecules are dis­ordered. The structure was refined as a non-merohedral twin.
Nuclear Data Sheets for A=207

The available experimental data pertaining to the nuclear structure of nuclei with A=207 are compiled; the results from various decay and reaction measurements are compared and evaluated. Inconsistencies and discrepancies in the level schemes are discussed. Level properties, gamma-ray properties, and comments are presented following the data on the relevant nucleus.
Aspergillus osteomyelitis of the proximal humerus: a case report

Aspergillus osteomyelitis is an extremely rare manifestation of invasive aspergillosis. Generally, patients in states of significant immune deficiency are very susceptible to invasive aspergillosis. We report a case of Aspergillus osteomyelitis of the proximal humerus in an immunocompetent patient that required aggressive oral antifungal therapy, surgical debridement, and placement of an antifungal-impregnated cement spacer. Subsequently, her shoulder was reconstructed using a reverse total shoulder prosthesis The clinical course, radiographic findings, histology, and management rationale are presented.
Chemical impurity effects on transport in polymer transistors

Exposure of unencapsulated bottom gate polythiophene thin film transistors (TFTs) to several organic and inorganic volatile chemicals induces large changes in the TFT properties. Various neutral molecules cause the mobility of the TFT to decrease and enhance the bias stress effect, with the changes being reversible upon annealing. The effect on the mobility and stress are characteristically different for each compound and are attributed to different preferred locations in the host. Some molecules cause electronic doping of the semiconductor with corresponding changes in threshold voltage. In the case of the donor, ammonia, a gate-induced incorporation rate is observed. The distribution of acceptor energies of the recently found ozone acceptor is analyzed.
Rate of progression differs in frontotemporal dementia and Alzheimer disease

Objective: To compare survival and rates of cognitive and functional decline in patients with autopsy-confirmed frontotemporal dementia (FTD) and Alzheimer disease (AD) in a large multicenter study. Background: Despite advances in the clinical characterization of FTD, little is known about its rate of progression. Characterizing survival and rate of decline in FTD is important because it can provide prognostic guidelines and benchmarks to use in the evaluation of disease-modifying drugs. Methods: Seventy patients with FTD and 70 patients with AD who were followed by seven Alzheimer disease research centers until confirmation of diagnosis at autopsy were matched for overall age, education, and Mini-Mental State Examination (MMSE) score at initial evaluation. Survival and rates of cognitive and functional decline were compared. Results: Patients with FTD had significantly shorter survival from initial evaluation to death than patients with AD (FTD = 4.2 years, AD = 6.0 years; log-rank test = 5.17, p Conclusions: The results are consistent with shorter survival and faster rates of cognitive and functional decline in patients with frontotemporal dementia (FTD) compared to those with Alzheimer disease (AD). This suggests that FTD follows a more malignant disease course than AD once dementia is clinically recognized.
Computer support for teaching large-enrollment courses

Computing systems are particularly useful for teaching support of large-enrollment courses where essentially the same material is covered during successive course offerings. Described herein are the computer capabilities developed and used for teaching introductory computer science courses at West Virginia University. Capabilities include examination question data base creation and maintenance, automated examination preparation and grading, and student records handling.
Dyadic interactions with avatars in immersive virtual environments: high fiving

Collaborative immersive virtual environments allow the behavior of one user to be observed by other users. In particular, behavior of users in such an environment is represented by each user possessing a self-avatar, a digital representation of themself. In this study we examined dyadic interactions in a collaborative immersive virtual environment when both users were present in the same physical space. This collocation in physical space allows for physical interaction between users as well as virtual interaction. In the context of a common physical gesture, high fiving, we examined the question of whether the form of the self-avatar was important, and whether collocation in the physical world provided benefits or not. We find that the form of the avatar is important but that physical collocation is not. These results reinforce the growing body of evidence that indicates that having a full-body avatar in a virtual environment provides benefits, and these results are significant because they demonstrate this in the context of a dyadic interaction.
The Time Course and Impact of Consumers' Erroneous Beliefs about Hedonic Contrast Effects

Results from four experiments indicate that people expect to enjoy an experience more when it will follow a worse experience. We find that consumers expect hedonic contrast effects even when they do not experience such effects. Whereas individuals remember the absence of contrast effects after a short delay (study 1), individuals reporting retrospective judgments after a long delay (study 2) recalled that they had experienced contrast effects. These biased memories about contrast effects are eliminated when individuals focus on enjoyment during the experience. The present experiments document the time course of erroneous beliefs about contrast effects, mechanisms underlying their resistance to change, and the impact of these expectations about contrast effects on consumer choice.
Robust Adaptive Control of Mildly Nonlinear Systems With Time Varying Input/Output Delays

Many systems must operate in the presence of delays both internal to the system and in its inputs and outputs. In this paper we present a robustness result for mildly nonlinear systems. We use this result to show that, for small unknown time varying input delays, a simple adaptive controller can produce output regulation to a neighborhood with radius dependent upon the size of an upper bound on the delay. This regulation occurs in the presence of persistent disturbances and the convergence is exponential. We conclude with an example to illustrate the behavior of this adaptive control law.Copyright © 2012 by ASME
Acidosis Effects on Insulin Response During Glucose Tolerance Tests in Jersey Cows

The effect of metabolic alkalosis and acidosis on insulin response to glucose tolerance tests was determined for cows fed a high cation diet to induce a state of metabolic acidosis. The anion diet to induce a state of metabolic acidosis. The glucose tolerance test (500 mg of glucose/kg of BW infused i.v. over 10 min) caused a rapid increase in plasma glucose and insulin concentrations. Plasma glucose concentrations were highest, and plasma insulin concentrations were lowest, during metabolic acidosis. These results suggest that insulin secretion is impaired during metabolic acidosis, which may reduce tissue uptake of glucose. Correction of metabolic acidosis by oral administration of sodium bicarbonate prior to glucose tolerance testing increased blood pH and bicarbonate concentrations and partially restored insulin response to the glucose tolerance test. Interestingly, sodium bicarbonate also caused an elevation in plasma cortisol concentrations. We concluded that glucose utilization is altered in cows with metabolic acidosis. The correction of acidosis associated with diseases such as diarrhea and ketosis may improve the therapeutic benefit of glucose infusions used to treat these diseases.
An averaging technique for detection of EEG-intracellular potential relationships

Abstract A technique is described which permits simultaneous averaging of both EEG and intracellular slow activity time-locked to the spike discharges of a single unit. The resultant wave forms allow visualization of relationships which may not be evident in unprocessed records.
Is False Spike, Quadrula mitchelli (Bivalvia: Unionidae), Extinct? First Account of a Very Recently Deceased Individual in Over Thirty Years

Abstract A recent survey of the San Saba River in San Saba County, Texas, has yielded the first record in >30 years of a very recently deceased individual (i.e., with tissue present within the shell) of the unionid mussel Quadrula mitchelli (false spike). This very recently dead individual suggests that living populations of Q. mitchelli might still exist in the San Saba River. Our results provide evidence that surveys in remote areas may help to locate populations of rare species of unionid mussels.
Global Structures of Common Difference and Minority Empowerment: Transforming Subjectivities and Creating Alliances in an Aotearoa/New Zealand School

This article discusses an effect of the emerging “global structures of common difference” on minority group empowerment. Researchers suggest that structures of difference often limit the ways of being. This article introduces more productive effects and shows the possibility of proactively expanding alliances by the use of global structures of common difference. Based on fieldwork done in 1997 through 1998 at a school in Aotearoa/New Zealand, where Indigenous Māori and recent Asian immigrants, both minorities, live in tension, this article illustrates the emergence of a Māori–Asian alliance against mainstream New Zealanders' insensitivity to minority languages through evocations of global structures of common difference.
Drugs and the production of temporal intervals in the rat

Abstract 1. 1. The widespread use and abuse of psychoactive compounds have increased the reports of drug-induced perceptual distortions and have generated an interest in the occurrence of such phenomena in non-human species. 2. 2. In a paradigm similar to human timing procedures, water-deprived rats were differentially reinforced for depressing a lever for 4.5 to 5.5 sec. 3. 3. Administration of amphetamine and tetrahydrocannabinol resulted in premature release of the lever (“short” errors); lysergic acid diethylamide and chlorpromazine prolonged depression of the lever beyond the required interval (“long” errors). 4. 4. The procedure employed appears sensitive to drug-induced shifts in timing behavior and permits direct comparison between the results of timing experiments with lower animals and the data obtained from the temporal production experiments commonly used with humans.
Modeling the Seasonal Dependence of the Atmospheric Response to Observed El Niños in 1962–76

Abstract Two 15-year atmospheric GCM integrations are conducted with the lower boundary over the tropical Pacific being forced by observed month-to-month sea surface temperature (SST) changes during the period 1962–76. A descriptive account is given on selected aspects of the 30-year model climatology, as well as the anomalous model behavior through the life cycles of El Nino–Southern Osicillation (ENSO) episodes centered in the years 1965, 1969 and 1972. These model results are compared with available observations reported in the published literature. Particular attention is devoted to the timing of various simulated meteorological phenomena with respect to the spatially and temporally evolving SST forcing, and to the climatological seasonal cycle. An assessment is made of the capability of the model to simulate the seasonal dependence of various climatological features relevant to ENSO. The phenomena examined include the flow field and rainfall in different monsoon regions, the planetary scale waves in ...
Severe intraoperative hypertension and opioid-resistant postoperative pain in a methadone-treated patient.

Abstract Patients who are treated with methadone present challenges for the anesthesiologist. We report the untoward effects of rapid preoperative methadone tapering on the operative and perioperative course of a patient who required emergency surgery. The patient’s exaggerated stress response to surgery and severe intractable postoperative pain might have resulted from unrecognized methadone withdrawal. Continuation of methadone treatment in patients who have surgery may prevent exaggerated intraoperative hemodynamic responses to surgical stimuli and unnecessary postoperative suffering.
Trypsin digest protocol to analyze the retinal vasculature of a mouse model.

Trypsin digest is the gold standard method to analyze the retinal vasculature 1-5. It allows visualization of the entire network of complex three-dimensional retinal blood vessels and capillaries by creating a two-dimensional flat-mount of the interconnected vascular channels after digestion of the non-vascular components of the retina. This allows one to study various pathologic vascular changes, such as microaneurysms, capillary degeneration, and abnormal endothelial to pericyte ratios. However, the method is technically challenging, especially in mice, which have become the most widely available animal model to study the retina because of the ease of genetic manipulations 6,7. In the mouse eye, it is particularly difficult to completely remove the non-vascular components while maintaining the overall architecture of the retinal blood vessels. To date, there is a dearth of literature that describes the trypsin digest technique in detail in the mouse. This manuscript provides a detailed step-by-step methodology of the trypsin digest in mouse retina, while also providing tips on troubleshooting difficult steps.
Terpene variability of mainland Pinus radiata

Abstract Wood and foliage mono- and sesquiterpenes of 45 Pinus radiata trees from the three native mainland populations in California were analysed using conventional and chiral gas chromatography. The wood was found to contain no detectable sesquiterpenes. Wood monoterpenes mainly consisted of β-pinene [98.5% (−), 1.5% (+)] and variable ratios of (−) and (+)α-pinene, the (−) enantiomer predominating in the southernmost population; twenty other monoterpenes were detected. The main foliage monoterpenes were (−)α- and (−)β-pinene, (−)limonene and (−)β-phellandrene. (−)α-Pinene increased from north to south, while (−)β-phellandrene and especially (−)limonene decreased. The predominant foliage sesquiterpenes were caryophyllene, germacrene D, bicyclogermacrene and 4α-hydroxygermacra-1(10),5-diene (4αHGD); twenty-four other sesquiterpenes were detected. The central (Monterey) population was distinguished by higher amounts of germacrene D and decreased levels of caryophyllene, bicyclogermacrene and 4αHGD. Canonical discriminant analysis of each data set (foliage monoterpenes, sesquiterpenes and wood monoterpenes) for all trees showed good separation among the populations with about 95% of the trees correctly grouped. When the three data sets were combined, the populations were completely separated and all trees were correctly grouped. The Mahalanobis distance between the southern pair (Monterey/Cambria) was less than between the northern pair (Ano Nuevo/Monterey).
Changes in the Electrochemical Potential Difference for HCO3‐‐ between Blood and Cerebrospinal Fluid and in Cerebrospinal Fluid Lactate Concentration during Isocarbic Hypoxia1

The changes in csf [HCO3-] and [lactate] were followed in dogs whose arterial pH, Pco2, and [HCO3--] were kept constant during 6 hrs hypoxia or normoxia. The results confirm that hypoxia causes a lowering of [HCO3-]csf. We believe it is reasonable to assume that an increased anaerobic glycolysis in the brain is responsible for titrating HCO3-- out of csf during isocarbic hypoxia although the lactate concentration in csf increased only about one third as much as the [HCO3--] decreased. The action of hypoxia on [HCO3-] esf is expressed in terms of its effect on the electrochemical potential difference for HCO3-- between mean capillary plasma water and csf.
Crystal structure of lactadherin C2 domain at 1.7A resolution with mutational and computational analyses of its membrane-binding motif.

Abstract Lactadherin is a phosphatidyl-l-serine (Ptd-l-Ser)-binding protein that decorates membranes of milk fat globules. The major Ptd-l-Ser binding function of lactadherin has been localized to its C2 domain, which shares homology with the C2 domains of blood coagulation factor VIII and factor V. Correlating with this homology, purified lactadherin competes efficiently with factors VIII and V for Ptd-l-Ser binding sites, functioning as a potent anticoagulant. We have determined the crystal structure of the lactadherin C2 domain (Lact-C2) at 1.7A resolution. The bovine Lact-C2 structure has a β-barrel core that is homologous with the factor VIII C2 (fVIII-C2) and factor V C2 (fV-C2) domains. Two loops at the end of the β-barrel, designated spikes 1 and 3, display four water-exposed hydrophobic amino acids, reminiscent of the membrane-interactive residues of fVIII-C2 and fV-C2. In contrast to the corresponding loops in fVIII-C2 and fV-C2, spike 1 of Lact-C2 adopts a hairpin turn in which the 7-residue loop is stabilized by internal hydrogen bonds. Further, central glycine residues in two membrane-interactive loops may enhance conformability of Lact-C2 to membrane binding sites. Mutagenesis studies confirmed a membrane-interactive role for the hydrophobic and/or Gly residues of both spike 1 and spike 3. Substitution of spike 1 of fVIII-C2 into Lact-C2 also diminished binding. Computational ligand docking studies identified two prospective Ptd-l-Ser interaction sites. These results identify two membrane-interactive loops of Lact-C2 and provide a structural basis for the more efficient phospholipid binding of lactadherin as compared with factor VIII and factor V.
Effect of Orientation of Porphyrin Single-Crystal Slices on Optoelectronic Properties

Millimeter-sized organic single-crystal slices of methylpyrroporphyrin XXI ethyl ester (MPPEE) have been prepared by capillary filling at its melting point (∼250 °C) between two parallel pieces of glass coated with indium−tin oxide (ITO) and separated by about 2−3 μm. Crystal orientation was characterized with polarized light under an optical microscope. MPPEE single-crystal slices with different orientations appeared as dramatically different colors between two crossed polarizers. The relationship between crystal orientation and optoelectronic properties was investigated by monitoring the photocurrent flow through ITO/MPPEE/ITO symmetrical sandwich cells. The short-circuit photocurrent strongly depended on crystal orientation, varying by more than 1 order of magnitude. When a light spot (∼150 μm in diameter) was scanned across adjacent MPPEE single-crystal domains with different orientations, short-circuit photocurrents generated at different spots within the same crystal domain were essentially constant...
Use of styrene‐maleic anhydride copolymers (SMA resins) in emulsion copolymerization

The composition and quantity of styrene-maleic anhydride (SMA) copolymer resins were varied in emulsion copolymerizations of methyl methacrylate and n-butyl acrylate conducted by both batch and semicontinuous processes. The resulting particle sizes and levels of coagulum were measured to determine the optimum conditions for incorporation of the SMA resins into the resulting latexes. A semicontinuous process, in which no buffer was included and the SMA was added in a second stage comonomer emulsion, was found to produce coagulum-free latexes. These recipes, however, relied on nucleation of the polymer particles by conventional surfactants [nonyl phenol poly(ethylene) oxide and its corresponding sulfate salt] with a first-stage addition of a monomer emulsion prepared with these surfactants. SMA1000, having a 1/1 ratio of styrene to maleic anhydride in its copolymer, was determined to be the preferred resin (as opposed to SMA2000 and SMA3000, having SMA ratios of 2/1 and 3/1, respectively) because it interacted the least with conventional surfactants, which allowed its ready incorporation into coagulum-free recipes. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 70: 2729–2747, 1998
Spatial and temporal covariability in early ocean survival of Chinook salmon (Oncorhynchus tshawytscha) along the west coast of North America

Knowledge of the spatial and temporal extent of covariation in survival during the critical ocean entry stagewill improve our understanding of how changing ocean conditions influence salmonproductivity andmanagement.Weused data from the Pacific coastwide coded-wire tagging program to investigate local and regional patterns of ocean survival of Chinook salmon (Oncorhynchus tshawytscha) from the Central Valley of California to southeasternAlaska from1980–2006.Ocean survival of fishmigrating as subyearlings covaried strongly fromVancouver Island toCalifornia. Shorttermcorrelationsbetweenadjacent regions indicated this covariability increased, beginning in the early 1990s. Chinook salmon survivals exhibited a larger spatial scale of variability (50%correlation scale: 706 km) than those reported forother northeast PacificOcean salmon. This scale is similar to that of environmental variables related to ecosystem productivity, such as summer upwelling (50% correlation scale: 746 km) and sea surface temperature (50% correlation scale: 500–600 km). Chinook salmon ocean survival rates from southeastern Alaska and south of Vancouver Islandwere not inversely correlated, in contrast to earlier observations based on catch data, but note that our data differ in temporal and spatial coverage from those studies. The increased covariability in Chinook salmonocean survival suggests that themarine phase contributes little to the reduction in risk across populations attributable to the portfolio effect. In addition, survival of fish migrating as yearlings from the Columbia River covaried with Chinook salmon survival from the northernmost regions, consistent with our understanding of their migration patterns.
CARDIAC INFECTIONS IN THE IMMUNOSUPPRESSED PATIENT

Over the last 20 years, there has been a marked rise in the number of immunosuppressed patients. This is because of increasing numbers of patients with AIDS, those who receive various types of organ transplants, and those who receive more aggressive therapy for hematologic and solid malignancies. Much has been learned about the various types of infections to which these individuals are subjected. Cardiac involvement in these states, however, remains poorly characterized. Indeed, the index of a textbook, dedicated to this subject, only contains one reference to infections involving the heart. 140 This situation is the result of many factors. Cardiac infections of the immunosuppressed (CII) are not as clinically apparent on physical examination or on various imaging studies as those of other organs. Documentation of visceral involvement by opportunistic organisms, such as Candida species, Aspergillus species, Toxoplasma gondii, and cytomegalovirus (CMV), is hard to establish. 134 Infection of the heart with these may be muted by the immunosuppressed state itself, by the various treatment modalities, and by the failure of these pathogens to elicit much of an inflammatory response. There may be simultaneous involvement of one or more organ systems. These concurrent battles make it extremely difficult to pinpoint the contribution of the cardiac infection to the patient's overall clinical condition. Of all the immunosuppressive states, cardiac infections in AIDS have been studied the most thoroughly. Even for this disease, the incidence of cardiac infections and the significance of isolation of various organisms from heart tissue remain unclear. CII are produced by organisms that take advantage of a particular defect in the patient's defenses. For example, infections with Aspergillus are seen in patients with significant leukopenia. In transplant patients, the pathogens may arise from the environment or from the donated tissues themselves. 3 Endocarditis in the impaired host usually is nosocomial in origin. 26 It has less to do with immunosuppressive state than with the breakdown of the skin barrier as a consequence of invasive vascular procedures, such as the use of Swan-Ganz catheters.
Proteins with pathogenic polyglutamine expansion inhibit fast axonal transport

Several neurological diseases, including Huntington's and spinobulbar muscular atrophy (SBMA), are the result of pathogenic activities of expanded polyglutamine (polyQ) tracts. The reasons for the late onset of the disease and for the special susceptibility of certain populations of neurons remain unknown, as are the mechanisms of polyQ induced neurodegeneration. Based on the observation that Huntingtin can be associated with vesicles in transport, we examined the effects of polyQ on rates of axonal transport and on cellular functions that are strongly dependent on prompt delivery of cellular components. Pathogenic forms of Huntington inhibited both anterograde and retrograde axonal transport in the squid axoplasm, while normal Huntington protein had no effect. To test the activity of polyQ on cellular functions in intact neurons, cell lines stably expressing either wild type or SBMA pathogenic forms of the androgen receptor were examined. PolyQ expansion had no effect on rates of proliferation, but negatively affected process elongation. The same polyQ constructs that most severely affected the elaboration of cellular processes in SH-SY5Y cells were the ones most effective at inhibiting axonal transport in the squid. Taken together, our data are consistent with polyQ proteins altering the regulation of microtubule dependent transport processes.
Measures of ecosystem structure and function derived from analysis of flows.

Several measures of ecosystem structure and function are derived from the application of economic input-output analysis to ecosystem compartment models. Total system throughflow (TST) is defined as the sum of all compartmental throughflows. Average path length of the i th inflow (APL 1 ) is defined as the average number of compartments through which the i th inflow passes. Average path length for an average inflow (ĀPL) is the mean of APL 1 weighted according to size of the inflows. ĀPL is shown to be equal to TST divided by the sum of all inflows. TST can be partitioned into a portion due to cycled flow (TST o ) and a portion due to flow straight through the system (straight throughflow, TST s ). The portion of ĀPL due to cycled flow divided by the portion due to straight throughflow is the cycling index (CI). This index indicates how many times further than the straight throughflow path length an average system inflow will travel because of cycling. Three simple ecosystem models are examined to demonstrate the utility of these measures in explaining ecological phenomena.
Processing and mechanical properties of AlB2 flake reinforced Al-alloy composites

Abstract A new process to produce high-purity AlB 2 single crystals in an Al Cu alloy was developed. This process suppressed the formation of the AlB 12 phase by argon quenching from 1300°C to room temperature. The high-temperature heat treatment was coupled with a melt infiltration step to produce AlB 2 reinforced Al Cu composites, with volume fractions of reinforcement up to 20%. Microstructural examination of these composites indicated that the aspect ratio of the flakes was approximately 30 with a high degree of homogeneity in the as-cast structure. Mechanical properties of the composites were measured and compared with those of the unreinforced matrix alloy. At a volume fraction of 20% reinforcement, the composite showed an 80% increase in strength at room temperature with 1% loss of strength up to 150°C. Higher strengths were obtained by partially aligning the flakes along the tensile axis.
Low vision reading with sequential word presentation

Individuals with scotomas in the center of their visual fields usually read much more slowly than visually impaired individuals without central scotomas. This study determines the extent to which inefficient eye movements could account for this difference. Using a technique described previously [Rubin and Turano (1992) Vision Research, 32, 895-902] text was presented sequentially, one word at a time at the same location in the visual field. Reading performance for rapid serial visual presentation (RSVP) was compared to conventional text presentation (PAGE) in 14 subjects with dense central scotomas (central field loss, CFL) and 9 without central scotomas (noCFL). Reading rates were faster with RSVP compared to PAGE, but CFL subjects improved less (by a factor of 1.5 +/- 0.41) than noCFL subjects (by a factor of 2.1 +/- 0.38). When reading rate (words/min) was converted to average word duration (msec/word) the reduction in word duration for RSVP compared to PAGE text averaged 150 msec for normal subjects, 171 msec for noCFL subjects, and 250 msec for CFL subjects. We hypothesized that the reduction in word duration was attributable to a reduced number of saccades/word. We confirmed this hypothesis by measuring the number of saccades during RSVP and PAGE reading using a scanning laser ophthalmoscope in four subjects with CFL. All of the subjects made fewer saccades during RSVP than PAGE reading (average reduction = 1.3 +/- 0.5 saccades/word). But even with the reduced number of saccades, CFL subjects required longer word durations than noCFL subjects. These results indicate that inefficient eye movements account for only part of the reduction in reading speed caused by CFL. An additional and potentially more important factor is the limited rate at which peripheral retina can perform the pattern decoding tasks required for reading.
Dye titrations of covalently closed supercoiled DNA analyzed by agarose gel electrophoresis

Abstract We have developed a rapid electrophoretic technique for performing ethidium bromide dye titrations in cylindrical 0.7% agarose gels. The technique was used to analyze the extent of supercoiling in circular covalently closed SV40, Co1E1, and pSC101 DNA. We have estimated the superhelical densities of SV40, Co1E1, and pSC101 DNA to be −0.050, −0.078, and −0.085 respectively. The results obtained for native SV40 DNA correlate well with previously published values for the superhelical density of this DNA when these values are corrected to reflect a 26° duplex unwinding angle for ethidium bromide. Ethidium bromide concentrations sufficient to partially relax a supercoiled DNA allow the DNA to be resolved into a series of discrete bands in agarose gels. The distribution of bands represents a natural heterogeneity in the superhelical densities of the DNA molecules in the population.
Climate Change Trade‐Offs in the Side‐Blotched Lizard (Uta stansburiana): Effects of Growing‐Season Length and Mild Temperatures on Winter Survival

Abstract An expanding body of literature has demonstrated that global climate change continues to adversely affect many populations, species, and ecosystems. However, life‐history theory also predicts possible benefits from longer growing seasons and less severe winters, particularly for ectotherms. To test the idea that climate change will have benefits as well as costs, I studied the impacts of growing‐season length on growth and overwintering conditions on survival time using side‐blotched lizards (Uta stansburiana). Experiments in replicate field enclosures revealed that fall growing‐season length has a direct effect on overwintering body size. Laboratory experiments revealed that both size and overwintering temperature have direct effects on winter survival time. Larger lizards are more likely to survive longer regardless of winter temperature. Furthermore, animals in colder (but still mild) winter microenvironments are more likely to survive longer than those in warmer winter environments. These res...
Auditory Morphology and Hearing Sensitivity in Fossil New World Monkeys

In recent years it has become possible to investigate the hearing capabilities in fossils by analogy with studies in living taxa that correlate the bony morphology of the auditory system with hearing sensitivity. In this analysis, we used a jack-knife procedure to test the accuracy of one such study that examined the functional morphology of the primate auditory system and we found that low-frequency hearing (sound pressure level at 250 Hz) can be predicted with relatively high confidence (±3-8 dB depending on the structure). Based on these functional relationships, we then used high-resolution computed tomography to examine the auditory region of three fossil New World monkeys (Homunculus, Dolicocebus, and Tremacebus) and compared their morphology and predicted low-frequency sensitivity with a phylogenetically diverse sample of extant primates. These comparisons reveal that these extinct taxa shared many auditory characteristics with living platyrrhines. However, the fossil with the best preserved auditory region (Homunculus) also displayed a few unique features such as the relative size of the tympanic membrane and stapedial footplate and the degree of trabeculation of the anterior accessory cavity. Still, the majority of evidence suggests that these fossil species likely had similar low-frequency sensitivity to extant South American monkeys. This research adds to the small but growing body of evidence on the evolution of hearing abilities in extinct taxa and lays the groundwork for predicting hearing sensitivity in additional fossil primate specimens.
Pollinator behaviour and the evolution of Louisiana iris hybrid zones

Pollinator preference may influence the origin and dynamics of plant hybrid zones. Natural hybrid populations between the red-flowered Iris fulva and the blue-flowered Iris brevicaulis are found in southern Louisiana. The genetic structure of these populations reflects a lack of intermediate genotypes. We observed pollinator behaviour in an experimental array with five plants each of I. fulva, I. brevicaulis, their F1, and the first backcross generation in each direction, to obtain data on flower type preferences and transitions between flower types. The most abundant visitors were Ruby-throated Hummingbirds (Archilochus colubris) and workers of the bumblebee Bombus pennsylvanicus. Hummingbirds visited I. fulva twice as often as I. brevicaulis and visited hybrids at intermediate frequencies. Bumblebee workers preferred the purple-flowered F1s and visited plants of I. fulva and the backcross to I. fulva more often than I. brevicaulis and its backcross. Overall, F1 flowers were visited most frequently. Both hummingbirds and bumblebees visited nearest neighbours in almost 80% of the interplant movements. This meant that a majority of movements were between different flower types, rather than between plants of the same type. Findings from the present study suggest that pollinator preference is not a major causal factor for the lack of intermediate genotypes in natural iris hybrid populations. Instead, pollinator behaviour in our array promoted mixed mating between flower types belonging to different pollination syndromes. However, owing to predominant nearest-neighbour visitation, the spatial distribution of parental and hybrid genotypes (in concert with pollinator behaviour) will have a strong influence on mating patterns and thus the genotypic structure and evolution of Louisiana iris hybrid zones.
High temperature structural transformations of few layer graphene nanoribbons obtained by unzipping carbon nanotubes

Multilayer and few layer graphene nanoribbons produced by oxidative unzipping of carbon multiwalled carbon nanotubes (MWNT 10 > N > 5) and N ≤ 4 carbon few walled nanotubes (FWNT) were annealed at temperatures up to 1400 °C and the resulting carbon nanostructures were studied. Transmission electron microscopy imaging of the graphene nanoribbons annealed in bulk shows higher structural stability in larger width multilayer graphene nanoribbons than in narrow few layer nanoribbons. Fringes of dark and bright contrast along the edges of MLG indicate edge closure within the layers of the stacked graphene nanoribbons. On the other hand, narrow FLG nanoribbons fuse within each other or collapse when annealed leading to three different nanostructures: large area MLG plates several microns wide, graphitic onions of approximately 100 nm in diameter and nanocrystalline/amorphous composite particles.
Anomalous kink behavior in the current-voltage characteristics of suspended carbon nanotubes

Electrically-heated suspended, nearly defect-free, carbon nanotubes (CNTs) exhibiting negative differential conductance in the high bias regime experience a sudden drop in current (or “kink”). The bias voltage at the kink (Vkink) is found to depend strongly on gate voltage, substrate temperature, and gas environment. After subtracting the voltage drop across the contacts, however, the kink bias voltages converge around 0.2 V, independent of gate voltage and gas environment. This bias voltage of 0.2 V corresponds to the threshold energy of optical phonon emission. This phenomenon is corroborated by simultaneously monitoring the Raman spectra of these nanotubes as a function of bias voltage. At the kink bias voltage, the G band Raman modes experience a sudden downshift, further indicating threshold optical phonon emission. A Landauer model is used to fit these kinks in various gas environments where the kink is modeled as a change in the optical phonon lifetime, which corresponds to a change in the non-equilibrium factor that describes the existence of hot phonons in the system. Open image in new window
Excess neonatal thyroxine: Effects on learning in infant and adolescent rats

Previous reports have suggested that neonatal thyroxine administration may enhance learning ability in rats as infants but the rats become deficient in learning as they grow older. This experiment compared neonatally thyroxine-injected rats with injected and nonhanded controls on passive and active avoidance and a geotactic cold-escape discrimination. Thyroxine-injected infant rats were superior to controls on active avoidance, inferior on passive avoidance, and equal on discriminated escape. Adolescent rats which had received postnatal thyroxine were inferior to controls in Lashley III maze acquisition whether or not they had received supplementary thryoxine at the time of training. These data suggest that differences in locomotor activity, rather than in learning ability, account for early behavioral effects and that changes other than endocrine disturbances account for the adult deficits. The results are compatible with previous contentions that excess neonatal thyroxine disrupts the timing of brain development.
Fajitas and the Failure of Refrigerated Meatpacking in Mexico: Consumer Culture and Porfirian Capitalism

Tourists who visit a Mexican market to observe a butcher at work will readily notice the difference between the material cultures of meat in Mexico and the United States. Instead of thick, neatly cut steaks, wrapped in clear plastic, they will find butterflied strips of meat, corresponding to no known part of a cow, sawed with ragged edges but remarkable thinness, and hung on hooks and rods. Thick slabs called suadero might be steak except for the checkerboards carved across the front, and seemingly random chunks of retazo complete the baroque display of craftsmanship. Although of little use in making Anglo-American roasts or steaks, these cuts are ideal for such delicacies as carne asada (grilled meat) and mole de olla (chili pepper stew). Indeed, fajitas—skirt steak pounded thin and marinated, then seared quickly on a hot fire, and served with salsa and fresh tortillas— are nothing more than a Tex-Mex version of the standard method of cooking and eating beef in Mexico. Moreover, the differences between U.S. supermarket meat counters and Mexican artisanal market displays extend beyond national culinary preferences to reflect the historical growth of industrial supply chains. Indeed, meat provides a case study demonstrating the significance of consumer culture in shaping the development of Mexican capitalism during the dictatorship of Porfirio Diaz (1876-1911).
On the effects of migration and spatial heterogeneity on single and multiple species

Abstract We first investigate in a logistic model the effects of migration and spatial heterogeneity of the environment on the total population size at equilibrium of a single species. Our study shows that (i) the total population size is maximized at some intermediate migration rate, and hence is a non-monotone function of the migration rate; (ii) heterogeneity of the environment increases the population size. In the second part of this paper, these findings are applied to ecological invasions. For a two-species Lotka–Volterra competition model with migration, we show that (i) without migration, the invading species eliminates the resident species at every point of the habitat, whereas when migration is present, for certain ranges of migration rates the invader may be eliminated when it is rare; and (ii) without migration, the two species can coexist at every point of the habitat, whereas when migration is present, for some ranges of migration rates one of the species is extinguished for all initial conditions.
Effect of thyroid hormone on the regeneration of the hypoglossal nerve in rats.

Abstract The effect of l -thyroxin (T 4 ) administration on the regeneration of the hypoglossal nerve in adult rats was studied by the method of retrograde axonal transport of horseradish peroxidase (HRP). Small numbers of rats responded to T 4 (5 μg/day) with an accelerated axonal growth; however, higher doses (50 μg/day for 1 week and 10 μg/day thereafter) were without such effect. The number of HRP-labeled neurons was considerably higher in the hypoglossal nucleus on the transected side, suggesting that thyroid hormone might have stimulated the formation and/or retention of the polyneuronal innervation of the lingual muscles.