cssi/SciSciGPT-SciSciNet huggingface dataset:
Rapid incision of the Colorado River in Glen Canyon – insights from channel profiles, local incision rates, and modeling of lithologic controls

The Colorado River system in southern Utah and northern Arizona is continuing to adjust to the baselevel fall responsible for the carving of the Grand Canyon. Estimates of bedrock incision rates in this area vary widely, hinting at the transient state of the Colorado and its tributaries. In conjunction with these data, we use longitudinal profiles of the Colorado and tributaries between Marble Canyon and Cataract Canyon to investigate the incision history of the Colorado in this region. We find that almost all of the tributaries in this region steepen as they enter the Colorado River. The consistent presence of oversteepened reaches with similar elevation drops in the lower section of these channels, and their coincidence within a corridor of high local relief along the Colorado, suggest that the tributaries are steepening in response to an episode of increased incision rate on the mainstem. This analysis makes testable predictions about spatial variations in incision rates; these predictions are consistent with existing rate estimates and can be used to guide further studies. We also present cosmogenic nuclide data from the Henry Mountains of southern Utah. We measured in situ10Be concentrations on four gravel-covered strath surfaces elevated from 1 m to 110 m above Trachyte Creek. The surfaces yield exposure ages that range from approximately 2·5 ka to 267 ka and suggest incision rates that vary between 350 and 600 m/my. These incision rates are similar to other rates determined within the high-relief corridor. Available data thus support the interpretation that tributaries of the Colorado River upstream of the Grand Canyon are responding to a recent pulse of rapid incision on the Colorado. Numerical modeling of detachment-limited bedrock incision suggests that this incision pulse is likely related to the upstream-dipping lithologic boundary at the northern edge of the Kaibab upwarp. Copyright © 2009 John Wiley & Sons, Ltd.
The use of a water-soluble carbodiimide to study the interaction between Chromatium vinosum flavocytochrome c-552 and cytochrome c.

Abstract The interaction between horse heart cytochrome c and Chromatium vinosum flavocytochrome c -552 was studied using the water-soluble reagent 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC). Treatment of flavocytochrome c -552 with EDC was found to inhibit the sulfide: cytochrome c reductase activity of the enzyme. SDS gel electrophoresis studies revealed that EDC treatment led to modification of carboxyl groups in both the M r 21000 heme peptide and the M r 46000 flavin peptide, and also to the formation of a cross-linked heme peptide dimer with an M r value of 42000. Both the inhibition of sulfide: cytochrome c reductase activity and the formation of the heme peptide dimer were decreased when the EDC modification was carried out in the presence of cytochrome c . In addition, two new cross-linked species with M r values of 34000 and 59000 were formed. These were identified as cross-linked cytochrome c -heme peptide and cytochrome c -flavin peptide species, respectively. Neither of these species were formed in the presence of a cytochrome c derivative in which all of the lysine amino groups had been dimethylated, demonstrating that EDC had cross-linked lysine amino groups on native cytochrome c to carboxyl groups on the heme and flavin peptides. A complex between cytochrome c and flavocytochrome c -552 was required for cross-linking to occur, since ionic strengths above 100 mM inhibited cross-linking.
Evaluation of alternative measurement and data-processing options for enzyme-based biosensors

This paper describes an alternative measurement/data-processing approach for enzyme-based biosensors. The proposed approach, identified herein as a pseudo-equilibrium option, is designed to obtain the response corresponding to reaction of all the substrate in a small fixed volume of solution. This general approach has two important advantages relative to more conventional steady-state option. It yields constant high sensitivity over wide concentration ranges and it improves the ruggedness to changes in experimental conditions by factors of 10-fold or more relative to the steady-state option. Results obtained for an amperometric-based reactor/sensor system for glucose demonstrate constant sensitivity for glucose concentrations up to five-fold the Michaelis constant and order-of-magnitude improvements in ruggedness to changes in selected experimental variables. Regarding ruggedness, results show that the pseudo-equilibrium option is 11-, 150- and 32-fold less dependent on pH, temperature and sodium chloride concentration, respectively, than steady-state results obtained from the same data sets. Principal limitations of the implementation of the pseudo-equilibrium option reported here are the possible inconvenience of a flow system, long measurement times and more complex data-processing requirements than the steady-state option.
Common Errors and Pitfalls in Interpretation of the Adult Chest Radiograph

Abstract:The chest radiograph is the most commonly performed radiologic examination and is the imaging study that the majority of nonradiologist physicians are most likely to encounter in their clinical practice. Chest radiography, however, can be very complex and difficult to interpret accurately d
The prevalence of Escherichia coli O157.H7 in dairy and beef cattle in Washington State.

Escherichia coli O157.H7 was found in 10 of 3570 (0.28%) faecal samples from dairy cattle in 5 of 60 herds (8.3%). Several tentative associations with manure handling and feeding management practices on dairy farms were identified. Faecal/urine slurry samples, bulk milk samples, and milk filters from dairy herds were negative for E. coli O157.H7. E. coli O157.H7 was also isolated from 10 of 1412 (0.71%) faecal samples from pastured beef cattle in 4 of 25 (16%) herds. The prevalence of E. coli O157.H7 excretion in feedlot beef cattle was 2 of 600 (0.33%). The identification of cattle management practices associated with colonization of cattle by E. coli O157.H7 suggests the possibility that human E. coli O157.H7 exposure may be reduced by cattle management procedures.
CONSUMPTION‐John Paul II, Catholic social thought and the ethics of consumption

In this essay, the author identifies three reasons why consumption, or more precisely excessive consumption, is emphasized in Catholic social thought including most recently John Paul II’s 1991 encyclical Centesimus Annus: the moral conflict between the abundance enjoyed by the few and the poverty endured by the many; the threat to the environment from excessive consumption; and the human degradation from a cultural environment wherein having more is valued above being more. In his essay, Wilber offers a personalist alternative to the neo‐classical position that satisfying individual preferences, as expressed in the market, is the only measure of economic welfare.
Shakespeare and the Cultural Capital Tension: Advancing Literacy in Rural Arkansas

A multi-faceted Shakespeare festival in a small town in rural east central Arkansas, part of a larger Community Literacy Advocacy Project, represented a concerted effort to alter the discourse of decline in this economically troubled region but it also raised some challenging issues about how such projects distribute social and cultural capital among their participants.
Bright cyclic light rearing-mediated retinal protection against damaging light exposure in adrenalectomized mice.

Abstract Previous studies have shown that albino rats and mice raised in bright cyclic light are protected from light-induced retinal damage. We tested if the stress response mediated by the adrenal grand is involved in the initiation of this neuroprotective phenomenon. Balb/c mice that were adrenalectomized (Adrex) or sham operated at 28 days of age were kept under dim (5 lux) or bright (400 lux) cyclic light (12 h on/off) for 2 weeks. Thereafter, their electroretinogram (ERG), outer nuclear layer (ONL) thickness and area, and plasma corticosterone levels were measured in animals with (dim + light and bright + light groups) and without (dim and bright groups) damaging light exposure (3000 lux for 24 h). In the dim + light group, a- and b-wave amplitudes and the ONL thicknesses and areas were significantly higher in the Adrex animals than the sham animals, indicating that adrenalectomy itself yielded retinal protection. In the Adrex animals, the ONL areas were significantly larger in the bright + light group than the dim + light group, indicating that bright cyclic light rearing yielded further retinal tolerance, even in the absence of the adrenal gland. In sham animals, the plasma corticosterone concentration did not change between the dim and the light groups. Accordingly, glucocorticoid secreted from the adrenal gland is not likely to be required for the mechanisms of the light-adaptation neuroprotection phenomenon in mice.
Evaluation of Standard and Modified Sampling Heads for the International PBI Surface Air System Bioaerosol Samplers

This study substituted sampling heads with smaller holes to collect small particles with the International PBI Surface Air System (SAS) battery-powered, bioaerosol air samplers, which have proved inefficient in collecting small airborne particles such as free bacteria (e.g., < 2 µm). An Andersen six-stage (6-STG) sampler was used simultaneously with two SAS samplers (SAS high flow [SAS-HF] and Compact SAS [SAS-C]) to sample indoor air in two office environments. Discrepancies were observed in the flow rate results obtained using the manufacturer's Pitot Validation Kit (PVK). Air sampling results suggested no significant difference in the concentration of bacteria and fungi collected among the four sampling heads using either sampler model in a small sample (n=5) at either site. However, with an additional 15 samples at Site B (n=5+15=20), three of the four sampling heads statistically undersampled the 6-STG and the other sampling head. The field data were variable (geometric standard deviation [GSD]=1.25–...
The association between T-type Ca2+ current and outward current in isolated human detrusor cells from stable and overactive bladders.

OBJECTIVE To determine if bladder overactivity in humans is associated with an altered activity of Ca2+ channels in detrusor smooth muscle and the consequent activation of other ion channels. MATERIAL AND METHODS Samples of bladder were obtained from patients with urodynamically stable bladders, or with idiopathic detrusor overactivity. Isolated cells were patch-clamped with pipettes containing a Cs+-based filling solution to isolate inward currents, or a K+-filling solution to measure outward current. Components of inward current were separated according to their sensitivity to NiCl2 (≤100 µm) and nifedipine. RESULTS Ni2+-sensitive (t-type) and nifedipine-sensitive (l-type) current was recorded in all cells. The voltage- and time-dependent properties were similar in cells from both patient groups. However, the current density of the l-type current was less, and that of the t-type current was greater, in myocytes from overactive bladders. In cells from overactive bladders, the mean K+ current over the range − 80 to − 50 mV was also higher than in control cells. This current was sensitive to the large-conductance channel modulator iberiotoxin and to NiCl2 (100 µm) CONCLUSIONS Detrusor myocytes from overactive human bladders have a higher t-type Ca2+ current density; we propose that this increases transient outward currents, and so might contribute to higher levels of spontaneous activity.
The impact of supporters’ ideological preferences on parties’ coalition choices: Evidence from New Zealand and Japan

Works on coalition formation and survival have traditionally focused on tactical and policy considerations at the elite level, and frequently neglected the role of voters. This study draws attention to how policy preferences among supporters may constrain parties’ coalition choices and affect their subsequent electoral performance. New Zealand and Japan, which have seen both significant party system changes and the emergence of previously unfamiliar coalition cabinets as the new norm since the 1990s, provide suitable cases for hypothesis testing. Analysis of cross-temporal survey data demonstrates that the distance between the ideological mean of each coalition partner (measured by its supporters’ left—right positions) and the coalition mean is negatively correlated with its vote share change in the following election. Parties participating in or supporting an ideologically distant cabinet, especially when alternative coalition choices are possible, face particularly heavy electoral sanctions. These findi...
Vascular changes in the cirrhotic liver as studied by the injection technic

The hepatic vasculature was studied in 9 normal livers, 1 fatty liver, 7 livers with portal cirrhosis, and 3 with postnecrotic cirrhosis (one each of the granular, coarsely nodular, and lobar type). Injection-corrosion cast and latex-injection technics were employed to determine the gross alterations in the vascular architecture, the anatomical evidence for the existence of intrahepatic shunts, the degree of venous compression by regenerative nodules, and the source of the blood supply to the regenerative nodules.
School-based obesity prevention programs: an evidence-based review.

Objective: This review seeks to examine the effectiveness of school-based programs for reducing childhood overweight or obesity. Methods and Procedures: A systematic review of the research literature published since 1990 was conducted to identify experimental or quasi-experimental school-based curricular or environmental preventive interventions, with evaluation ≥6 months after baseline, which reported outcomes in terms of a measure of overweight. Results: Fourteen studies were identified, including one involving a nutrition-only program, two physical activity promotion interventions and eleven studies combining nutrition and physical activity components. Most studies (n = 10) offered weak (grade 2) quality evidence. One study offered strong (grade 4) evidence reducing the odds ratio for overweight in girls only, while four grade 2 studies reported significant improvements in BMI or at-risk-for overweight or overweight prevalence in boys, girls, or both. Twelve studies reported significant improvement in at least one measure of dietary intake, physical activity, and/or sedentary behavior. Discussion: Our ability to draw strong conclusions as to the efficacy of school-based obesity prevention programs is limited by the small number of published studies and by methodological concerns. Qualitative analysis suggests programs grounded in social learning may be more appropriate for girls, while structural and environmental interventions enabling physical activity may be more effective for boys. High-quality evaluation protocols should be considered essential components of future programs.
Routine preoperative lymphoscintigraphy is not necessary prior to sentinel node biopsy for breast cancer

Abstract Background: This prospective study was performed to ascertain the added benefit of lymphoscintigraphy to a standard method of intraoperative lymphatic mapping and sentinel node biopsy for breast cancer. Methods: Patients with invasive breast cancer were injected with 99m Tc sulfur colloid prior to sentinel node biopsy; preoperative lymphoscintigraphy was then performed in half of the patient population. Results: Sentinel node identification was possible in 45 of 50 patients (90%). All 14 patients (31%) with axillary nodal metastases had at least one histologically positive sentinel node (0% false negative rate). Lymphoscintigraphy revealed sentinel nodes in 17 of the 24 patients (70.8%) imaged. All 17 of these patients had one or more axillary sentinel nodes identified using intraoperative lymphatic mapping. In addition, 5 of 7 patients with a negative preoperative lymphoscintogram had an axillary sentinel lymph node(s) identified intraoperatively. None of the tumors showed drainage to the internal mammary lymph node chain by lymphoscintigraphy despite the fact that there were 5 patients with inner quadrant tumors. There was no significant advantage with respect to sentinel lymph node localization (91.7% versus 88.5%, P = not significant) or false negative rate (0%, both groups, P = not significant) in the group undergoing preoperative lymphoscintigraphy when compared with the patients in whom lymphoscintigraphy was not performed. Conclusions: Preoperative lymphoscintigraphy adds little additional information to intraoperative lymphatic mapping, and its routine use is not justified.
Fever in the lizard Dipsosaurus dorsalis.

FEVER is considered to be a universal response of warm-blooded animals to endotoxins1. Although during a fever a mammal uses behavioural as well as physiological means to increase its body temperature2, it is not known whether fever develops in an animal such as a lizard which regulates its body temperature largely by behaviour. For example, the desert iguana (Dipsosaurus dorsalis) regulates its body temperature close to 38.5° C if placed in a chamber with a temperature gradient3. If this lizard is placed in a temperature chamber in which one end is heated to above the animal's lethal body temperature (50° C) and the other end is maintained at room temperature, the lizard regulates its temperature by moving back and forth between the two sides4. Under these conditions, one can determine its high and low set-points (Fig. 1). The central nervous control of temperature in an ectotherm, such as a lizard, and an endotherm, such as the rabbit, appears to be quite similar. For example, both possess a hypothalamus which is thermally sensitive5,6, and lesions in the posterior hypothalamus in both lizards4 and mammals7 lead to an inability to maintain a high body temperature.
Gastroparesis in neonatal myotonic dystrophy

Myotonic dystrophy in the neonate is commonly accompanied by facial diplegia, generalized muscular hypotonia, talipes equinovarus, and muscular respiratory failure. The gastrointestinal manifestations of this disease include poor sucking, choking, regurgitation, aspiration, and swallowing difficulties. Gastroparesis can be a major contributor to the feeding difficulties experienced by these infants. We report on an infant with congenital myotonic dystrophy in whom a severe gastric motility problem was alleviated by metoclopramide therapy. This smooth muscle manifestation may be an important and potentially remediable source of morbidity in these infants.
Band gap reduction of ZnO for photoelectrochemical splitting of water

We combine first-principles density functional theory, material synthesis and characterization, and photoelectrochemical (PEC) measurements to explore methods to effectively reduce the band gap of ZnO for the application of PEC water splitting. We find that the band gap reduction of ZnO can be achieved by N and Cu incorporation into ZnO. We have successfully synthesized ZnO:N thin films with various reduced band gaps by reactive RF magnetron sputtering. We further demonstrate that heavy Cu-incorporation lead to both p-type doping and band gap significantly reduced ZnO thin films. The p-type conductivity in our ZnO:Cu films is clearly revealed by Mott-Schottky plots. The band gap reduction and photoresponse with visible light for N- and Cu-incorporated ZnO thin films are demonstrated.
Determination of temperature and no concentrations through the dark zone of solid-propellant flames

Absorption spectroscopy has been used to characterize the steady-state flame structure of solid propellants over a pressure range of 0.3 to 2.0 MPa. An arc-lamp light source and two spectrometer-intensified photodiode-array detectors formed the basic experimental setup from which NO and OH absorption spectra were acquired. Vibrationally resolved transitions in the A2Σ-X2II electronic system of NO from 230 to 250 nm comprise the absorption spectra from which temperatures and absolute NO concentrations are determined in the dark-zone region of the solid-propellant flames and rotationally resolved transitions in the A2Σ-X2II (0,0) vibrational band system of OH from 306 to 311 nm comprise the absorption spectra from which limunous-flame temperatures are determined. Both NO and OH are sufficiently well characterized that the spectra can be least-sequeres fitted with respect to a variety of parameters which include an instrument response function, an absorption baseline, a wave-length nonlinearity as well as the temperature and concentration. Three different propellants (JA-2, M9, and HMX2) that exhibit a dark zone have been studied as a function of pressure. The dark-zone temperatures ranged from about 1300 K to 1500 K and NO concentrations varied from 13 to 30 mole per cent depending on the propellant type and pressure. Temperatures in the luminous flame region reached values in agreement with the computed equilibrium, adiabatic flame temperatures.
Thyroid hormone and brain function. IV. Effect of triiodothyronine on visual evoked potentials and electroretinogram in man.

Abstract The effect of thyroid hormone on visual evoked potentials and upon dark-adapted red and white light electroretinograms (ERG) have been studied in eight male human subjects. They received 300 μg of triiodothyronine (T 3 ) for 3 days. The following observations were obtained. 1. 1. The latency and amplitude of the waves comprising the secondary component of visual evoked potentials were increased in all subjects. 2. 2. The rhythmic after-discharge of the evoked potentials was potentiated after the administration of T 3 . 3. 3. No significant change was present in either the red or white light ERG after dark adaption by the third day at this dose of T 3 .
Radionuclide Incorporation in Secondary Crystalline Minerals from Chemical Weathering of Waste Glasses

Data from corrosion and radionuclide sequestration studies on two waste glasses indicated chemical weathering resulted in the formation of zeolite minerals such as herschelite and analcime. We also found that these minerals incorporated ∼8–22%, ∼1- 13% and ∼8–25% of spiked 125I, 99Tc, and 75Se respectively. Increasing concentrations of radionuclides in spike solution resulted in higher degree of sequestration as observed by significantly higher proportion of stable isotopes (∼70–95% I, ∼58–100% Re, and ∼100% Se) in secondary minerals. The radionuclide incorporation mechanisms for these minerals appear to be mainly isomorphic substitution of Se and Re in tetrahedral sites and iodide substitution for framework oxygen.
The adsorption and decomposition of ethylene on Ni(110)

Abstract The interaction of ethylene gas with a Ni(110) surface has been studied by a combination of modulated beam mass spectrometry and Auger electron spectroscopy techniques. At temperatures below 350°C, ethylene is chemisorbed with unity initial sticking coefficient up to a saturation coverage of one carbon atom per surface nickel atom. Above 150°C, hydrogen evolution is observed concurrent with the adsorption process, the amount of hydrogen liberated corresponding to complete dehydrogenation of the ethylene. Indirect evidence also suggests dehydrogenation down to 25°C. A physisorbed ethylene species is observed to coexist with the chemisorbed layer. Above 350°C formation of a graphitic surface layer is observed. The results obtained are consistent with earlier photoemission spectrometric measurements of Demuth and Eastman (Phys. Rev. Letters 32 (1974) 1123).
Essential arginine residues in human liver arylsulfatase A.

Abstract Human liver arylsulfatase A was treated with arginine-specific reagents (diones), resulting in a loss of enzyme activitity with apparent first-order kinetics. Sulfite and borate—competitive inhibitors of the enzyme—provided complete protection from inactivation by phenylglyoxal. Sulfite and substrate each likewise protected against enzyme inactivation by 2,3-butanedione. A plot of pseudo-first-order rate constants of enzyme inactivation versus 2,3-butanedione concentrations suggests that an essential arginine residue is modified with a loss in function of the binding site or of the active site of the protein. Chemical analysis of the butanedione-treated sulfatase indicates that complete enzyme inactivation corresponds to a modification of only about 2 of the 20 arginine residues per enzyme subunit. Taken together, all of the results strongly suggest that arginine residues are essential for the activity of arylsulfatase A. An incidental discovery in this work is that borate ion is a competitive inhibitor of human arylsulfatase A with a Ki of 2.5 × 10−4 M.
A High-Density Admixture Scan in 1,670 African Americans with Hypertension

Hypertension (HTN) is a devastating disease with a higher incidence in African Americans than European Americans, inspiring searches for genetic variants that contribute to this difference. We report the results of a large-scale admixture scan for genes contributing HTN risk, in which we screened 1,670 African Americans with HTN and 387 control individuals for regions of the genome with elevated proportion of African or European ancestry. No loci were identified that were significantly associated with HTN. We also searched for evidence of an admixture signal at 40 candidate genes and eight previously reported linkage peaks, but none appears to contribute substantially to the differential HTN risk between African and European Americans. Finally, we observed nominal association at one of the loci detected in the admixture scan of Zhu et al. 2005 (p = 0.016 at 6q24.3 correcting for four hypotheses tested), although we caution that the significance is marginal and the estimated odds ratio of 1.19 per African allele is less than what would be expected from the original report; thus, further work is needed to follow up this locus.
Enhancing performance of wireless NoCs with distributed MAC protocols

Wireless NoC is an emerging paradigm to design high-bandwidth and energy-efficient communication backbones for massive multicore chips. The achievable performance of this type of on-chip interconnect infrastructure depends on the efficiency of the Media Access Control (MAC) protocol that arbitrates between the competing wireless nodes. In this work we propose the design of a distributed MAC protocol suitable for wireless NoC architectures. Compared to the widely used token passing scheme, a distributed MAC protocol improves scalability, provides better performance and lower overall energy dissipation. Depending on the traffic pattern, the proposed distributed MAC provides up to 23% improvement in energy delay product (EDP) when compared to the existing token passing scheme.
Real-time measurement of the weld pool surface in GTAW process

This study aims at real-time measurement /reconstruction of the specular three-dimensional (3D) weld pool surface under strong arc in gas tungsten arc welding (GTAW). A vision-based sensing system is used to project a dot-matrix laser pattern on the weld pool surface which is able to specularly reflect the laser pattern. This reflection pattern, deformed by the weld pool surface has been utilized to reconstruct the 3D shape of the weld pool surface. Based on careful analysis, the underlying reconstruction problem is formulated mathematically. An analytic algorithm is proposed resulting in the weld pool surface be reconstructed in real-time on average in 3.22 milliseconds. In order to verify the effectiveness of the proposed reconstruction algorithm, it is tested on objects with a priori knowledge of geometry having a specular surface. Then the robustness of the proposed reconstruction scheme is further validated using a real-time experiment.The detailed analysis of measurement error validates the accuracy of the proposed algorithm.
Desert dust aerosol age characterized by mass‐age tracking of tracers

[1] We introduce and apply to dust aerosols an efficient method to track tracer age (time since emission) as a function of space and time in large-scale geophysical models. Our mass-age tracking (MAT) method follows the full tracer lifecycles directly and does not depend on proxy, ensemble, or Green's function techniques. MAT sends a mass-age tracer through the same algorithms that the host models use to predict tracer mass processes and then estimates age as the ratio of mass-age to mass. We apply MAT to size-resolved dust aerosol tracers to study the age of dust that remains in the atmosphere and the age of dust at deposition. The results include the first global distribution maps of aerosol age. Dust age varies with location, time, and particle size and is strongly sensitive to climate, wind and precipitation in particular. The global average age of dust at deposition agrees with residence time at ∼2.7 days, while dust in the atmosphere is, on average, twice as old. As expected, older dust prevails far from sources, at higher altitudes and in smaller sizes. Dust age exhibits a seasonal cycle, stronger for larger dust particles, that peaks in April–June, the period of maximum Asian and North African emissions. The oldest dust at deposition falls in the Antarctic and South Pacific Convergence Zone about 1 month after emission. The mass-weighted ages provided by MAT are useful for investigating and parameterizing the evolution of aerosol physical and chemical properties.
Endometrial ablation in patients with myomas

Purpose of reviewThis review evaluates how the presence of uterine myomas may limit the ability to provide endometrial ablations for patients with menorrhagia, affect subsequent postoperative course and alter long-term outcome.Recent findingsNew instrumentation and the off-label use of some global a
Drug–drug interactions between anti-retroviral therapies and drugs of abuse in HIV systems

Introduction: Substance abuse is a common problem among HIV-infected individuals. Importantly, addictions as well as moderate use of alcohol, smoking, or other illicit drugs have been identified as major reasons for non-adherence to antiretroviral therapy (ART) among HIV patients. The literature also suggests a decrease in the response to ART among HIV patients who use these substances, leading to failure to achieve optimal virological response and increased disease progression.Areas covered: This review discusses the challenges with adherence to ART as well as observed drug interactions and known toxicities with major drugs of abuse, such as alcohol, smoking, methamphetamine, cocaine, marijuana, and opioids. The lack of adherence and drug interactions potentially lead to decreased efficacy of ART drugs and increased ART, and drugs of abuse-mediated toxicity. As CYP is the common pathway in metabolizing both ART and drugs of abuse, we discuss the possible involvement of CYP pathways in such drug interacti...
Oxide-Induced Initiation of Stress Corrosion Cracking in Irradiated Stainless Steel

Abstract Stainless steel (SS) samples were irradiated with protons at 400°C and strained in 288°C water to examine the role of oxide particles in the irradiation-assisted stress corrosion cracking ...
Cytoplasmic protein binds in vitro to a highly conserved sequence in the 5' untranslated region of ferritin heavy- and light-subunit mRNAs

Abstract The mRNAs for the heavy and light subunits of the iron-storage protein ferritin occur in cells largely as inactive ribonucleoprotein particles, which are recruited for translation when iron enters the cell. Cytoplasmic extracts from rat tissues and hepatoma cells were shown by an electrophoretic separation procedure to form RNA-protein complexes involving a highly conserved sequence in the 5' untranslated region of both ferritin heavy- and light-subunit mRNAs. The pattern of complex formation was affected by pretreatment of rats or cells with iron. Crosslinking by UV irradiation showed that the complexes contained an 87-kDa protein interacting with the conserved sequence of the ferritin mRNA. We propose that intracellular iron levels regulate ferritin synthesis by causing changes in specific protein binding to the conserved sequence in the ferritin heavy- and light-subunit mRNAs.
Role of aquaporins in endothelial water transport

The aquaporins (AQP) are a family of homologous water channels expressed in many epithelial and endothelial cell types involved in fluid transport. AQP1 protein is strongly expressed in most microvascular endothelia outside of the brain as well as in endothelial cells in cornea, intestinal lacteals, and other tissues. AQP4 is expressed in astroglial foot processes adjacent to endothelial cells in the central nervous system. Transgenic mice lacking aquaporins have been useful in defining their role in mammalian physiology. Mice lacking AQP1 manifest defective urinary concentrating ability, in part because of decreased water permeability in renal vasa recta microvessels. These mice also show a defect in dietary fat processing that may involve chylomicron absorption by intestinal lacteals. There is preliminary evidence that AQP1 might play a role in tumour angiogenesis and in renal microvessel structural adaptation. However AQP1 in most endothelial tissues does not appear to have a physiological function despite its role in osmotically driven water transport. For example mice lacking AQP1 have low alveolar capillary water permeability but unimpaired lung fluid absorption, as well as unimpaired saliva and tear secretion, aqueous fluid outflow, and pleural and peritoneal fluid transport. In the central nervous system mice lacking AQP4 are partially protected from brain oedema in water intoxication and ischaemic models of brain injury. Therefore although the role of aquaporins in epithelial fluid transport is in most cases well understood there remain many questions about the role of aquaporins in endothelial cell function. It is unclear why many leaky microvessels strongly express AQP1 without apparent functional significance. Improved understanding of aquaporin endothelial biology may lead to novel therapies for human disease, such as pharmacological modulation of tumour angiogenesis, renal fluid clearance and intestinal absorption.
Crosses of Blood: Sacred Space, Religion, and Violence in Bosnia-Hercegovina

The role of religion in the war in Bosnia-Hercegovina has been both obvious and invisible. It was obvious in that both perpetrators and victims of organized atrocities were identified by their religious tradition. It was invisible in that the religious manifestations were viewed either as incidental or as masks for deeper social, political, and economic issues; or else categorized exclusively as aspects of ethnicity.This essay examines the role of religion in the ideology of those carrying out "ethnic cleansing," as manifested in the literature of the religious nationalists and, particularly in the case of Catholic religious nationalism, in the language of destruction and construction of shrines. Juxtaposed to the shrine texts of religious nationalism is a vision of shrine preservation and reconstruction. The reconstruction efforts are viewed by their advocates as central to the construction of a pluriform Bosnia-Hercegovina in which all religions historically integral to Bosnian civilization will be viewed as equal and equally important elements of the national identity. By examining the struggle between these two visions of sacral monuments, we can better understand and evaluate the agency of religious institutions, leaders, and symbols in the Bosnian drama.
Molecular size and chain length distribution in Acanthamoeba cellulose

SYNOPSIS Evidence obtained by total hydrolysis, partial acetolysis, periodate oxidation, as well as treatment with amylase, emulsin, and Trichoderma virideβ-(14)-glucanase, verified that the alkali insoluble component of Acanthamoeba castellanii was pure β-(14)-glucan. The weight average chain length of the cellulose varied from DP = 3170 to DP = 4130 (mean DP = 3480) with polysaccharide obtained from seven seemingly identical cultures. Isolation of the cyst-wall cellulose by nondegrading means indicated that alkali extraction was not depolymerizing the polysaccharide. Fractionation of cellulose obtained from a single culture produced fractions from DP = 550 to DP = 4550 (mean DP = 3280; 98.7% of the original cellulose), indicating that the cellulose is polydisperse.
A new and simple model for GaAs heterojunction FET gate characteristics

The gate current-voltage characteristics for modulation-doped field-effect transistors (MODFETs) and heterostructure insulated-gate field-effect transistors (HIGFETs) are described using a simple model. This model, which is physically realistic, consists of two Schottky diodes in series: one is a metal-semiconductor (AlGaAs) Schottky diode and the other is an equivalent Schottky diode due to the heterojunction between the AlGaAs and GaAs. A novel technique is developed to characterize the parameters used for this model. The model is used to estimate the effective electron temperature in the channel close to the drain for MODFETs. The estimated electron temperature with 1 V drain-to-source voltage is as high as 80 degrees C at room temperature. Very good agreement between the calculated and measured results is obtained. This model and characterization technique are also suitable for other heterojunction FETs such as quantum-well MODFETs, etc. >
Genetics of hereditary colorectal cancer

Genetic factors can dramatically influence the risk of colorectal cancer, and the molecular bases of many hereditary colorectal cancer syndromes, including familial adenomatous polyposis (FAP), attenuated FAP (AFAP), and hereditary nonpolyposis colorectal cancer (HNPCC) have been elucidated. Additional syndromes continue to be defined as new genes, including MYH, are linked to the development of colonic polyps and cancer. The risks of colorectal cancer are variable and depend on the specific germline alterations. Some mutations are associated with a 100% lifetime risk of developing cancer, while others are associated with only a mild increase in risk. Although there are overlapping clinical features in many of these syndromes, they can be distinguished by the age at cancer diagnosis, inheritance pattern, number and distribution of polyps, specific histologic features of the cancers, and the presence of distinctive extracolonic features. The introduction and refinement of genetic testing has provided a new and invaluable tool for the diagnosis and assessment of cancer risk for suspected cases of hereditary colon cancer.
Integration of internet-based genetic databases into the medical school pre-clinical and clinical curriculum

Over the past several years, the field of medical genetics has continued to expand and is now impacting a broad range of medical care, mainly due to rapid advances in genetic technology and information generated by the Human Genome Project. Physicians from multiple disciplines will need to become familiar with genetic principles, and the availability of genetic databases on the internet is a valuable resource for medical students and physicians. To integrate these tools into medical student training, the University of Chicago Pritzker School of Medicine set out to develop multiple, interactive, case-based, educational sessions in the pre-clinical and clinical curriculum, designed to reinforce basic principles taught in the pre-clinical genetics class and demonstrate the usefulness of genetic information accessible via the internet in the clinical setting. Two interactive sessions and a self-assessment exercise were developed. The sessions took place in a computer classroom where each student had access to the internet and could work independently. The sessions used case-based scenarios to help students become familiar with internet based resources and demonstrate how genetic information can affect medical care. The sessions were well received by the student participants with 99% agreeing that the material was useful and important to clinical medicine. In a follow-up questionnaire 1/3 of the students reported using the databases presented during class in a clinical setting.
Comparison of agar dilution, broth microdilution, E-test, disk diffusion, and automated Vitek methods for testing susceptibilities of Enterococcus spp. to vancomycin.

An evaluation was undertaken to determine the optimal method for testing the susceptibilities of 100 clinical isolates and two reference strains of Enterococcus spp. to vancomycin in vitro. Six testing methods were studied by using the following media and incubation times: agar screen with the Synergy Quad Plate (Remel, Lenexa, Kans.), an in-house-prepared brain heart infusion (BHI) agar plate, and an in-house-prepared Mueller-Hinton (MH) agar plate, all incubated for 24 or 48 h; broth microdilution (Sensititre Just One Strip; AccuMed International, Inc., West Lake, Ohio) with BHI or cation-adjusted MH broth incubated for 24 or 48 h; agar dilution with BHI or MH agar incubated for 24 or 48 h; epsilometer test (E test; AB BioDisk, Solna, Sweden) with BHI or MH agar incubated for 24 or 48 h; disk diffusion with BHI or MH agar incubated for 24 or 48 h; and the automated Vitek method with the gram-positive susceptibility Staphylococcus aureus card and R02.03 software (bioMerieux, Inc., Hazelwood, Mo.). Growth failures occurred with MH media (n = 6) but not with BHI media. One growth failure occurred with the Vitek method. Results for each testing method for each Enterococcus strain were interpreted as susceptible, intermediate, or resistant according to current National Committee for Clinical Laboratory Standards (NCCLS) criteria and compared to the vancomycin resistance genotype (i.e., vanA, vanB, vanC-1, or vanC-2/3). For all methods, extension of the incubation time from 24 h to 48 h either produced no difference in the results or gave poorer results. The following methods produced no very major or major interpretive errors: broth microdilution with BHI media incubated for 24 h, agar dilution with BHI media incubated for 24 or 48 h, and E test with BHI media incubated for 24 or 48 h. Unacceptable frequencies of very major errors (> 1%) occurred with all methods for which MH media were used. Minor interpretive errors were frequent with all methods. These minor interpretive errors also occurred most frequently with Enterococcus strains with vanC genes, which encoded low-level vancomycin resistance (MIC or = 64 microg/ml). Modification of NCCLS breakpoints, especially for motile Enterococcus spp. (E. casseliflavus, E. flavescens, and E. gallinarum), may resolve this problem; however, in the current study, one E. faecalis strain and one E. faecium strain carried only the vanC gene. The agar screen method may also require reformulation. The current agar screen plate contains 6 microg of vancomycin per ml, which may not detect all low-level resistance associated with vanC genotypes. Nevertheless, the clinical significance of this low-level vancomycin resistance remains unknown.
Stretch responsiveness of Golgi tendon organs.

1. This report describes experiments on Ib afferents from tendon organs of the de-efferented soleus in acutely prepared cats in which: a) contrast was made of responses to passive forces generated by a dynamic stretch and to active forces generated by stimulating either the muscle nerve or small ventral root filaments; and, b) responses to static and dynamic stretch were related to physiological extents and rates of movement. 2. No significant differences were observed in tensions associated with threshold responses to active and passive inputs if rates of tension development were relatively similar and if the active force was generated by stimulation of the muscle nerve. Stimulation of small ventral rootlets revealed however that many motor units are “in parallel” and many “in series” with certain receptors. Thresholds of these receptors were much lower to active forces generated by “in series” motor units than to forces developed more randomly by graded stimulation of the muscle nerve. An absolute active force threshold was not gauged since it was estimated that at least some tendon organs can be driven by independent twitch contraction of 30–50 motor units. 3. Threshold responses to static stretch indicated that gradual flexion of the ankle joint (as for example on slow assumption of a crouched posture) would involve progressive recruitment of soleus Ib discharge with over 2/3rds of the units firing by the extreme of dorsi-flexion. Responses to dynamic stretch suggested that an even greater percentage of soleus tendon organs would be fired during ankle flexions associated with walking. During galloping the triceps surae undergoes an eccentric (lengthening) contraction at one phase of the step cycle and soleus Ib input to the spinal cord would then become even more pronounced. 4. In recent years the role of Golgi tendon organs in the reflex regulation of muscle has been reassessed with an emphasis on their ability to transmit continuously to the spinal cord information concerning the active force developed by muscle contraction and a de-emphasis of the significance of responses to muscle stretch. The present results emphasize however that soleus tendon organs are sufficiently sensitive to passive forces that muscle stretch can influence Ib input to the spinal cord in normal postural and locomotor activity. There is discussion of the functional significance of this finding and its relation to the central organization of Ib reflexes.
The Effect of Summer Vacation on Bilingual Preschoolers' Language Development.

The purpose of the investigation was to examine the developmental trajectories of bilingual preschoolers' comprehension of Spanish and English and to determine whether a lengthy summer vacation impacted children's development during the preschool years. Participants included 83 bilingual children who were followed over a 2-year period during which time children attended a federally funded preschool programme for children from low-income homes living in the US. Children were divided into two groups based on whether their scores on receptive language measures increased or decreased during their first year of Head Start. Results revealed that children whose scores increased experienced positive growth in their language comprehension in Spanish and English over the 2-year period, whereas children whose scores decreased during the first year continued to experience a negative developmental trajectory in their second year. Additionally, it was found that a lengthy summer vacation had a differential effect on children's development. Summer vacation had a negative effect on the developmental trajectories of children who experienced gains in their comprehension of English and Spanish and a positive impact on children whose scores declined during the school year. Clinical implications suggest that children may require differential support during the school year and summer vacation depending upon their developmental trajectories during the first year in preschool.