cssi/SciSciGPT-SciSciNet huggingface dataset:
Thermodynamic and kinetic constraints on reaction rates among minerals and aqueous solutions. II. Rate constants, effective surface area, and the hydrolysis of feldspar

Analysis of experimental data reported by Lagache (1965, 1976), Evans (1965), Busenberg (1975), Busenberg and Clemency (1976), Holdren and Berner (1979), Siegel and Pfannkuch (1984), and Chou and Wollast (1984) with the aid of irreversible thermodynamics and transition state theory (Aagaard and Helgeson, 1977, 1982) suggests that at temperatures at least up to 650°C, the rate of both congruent and incongruent feldspar hydrolysis in aqueous solutions far from equilibrium at pH ≲ 10.6 − (2300/T), where T stands for temperature in kelvins, is a function solely of effective surface area and pH at constant pressure and temperature. At higher pH, the rate is apparently pH-independent up to ~pH 8 at 25°C, where it again becomes pH-dependent at higher pH. Observations of scanning electron micrographs indicate that the cross-sectional area of etch pits on hydrolyzed feldspar grains is of the order of 10−9 to 10−8 cm2 and that the ratio of the effective to total surface area (which may or may not change with reaction progress) ranges from <0.01 to 1, depending on the grain size, dislocation density, and the extent of comminution damage on the surfaces of the grains. Apparent rate constants retrieved from experimental data reported in the literature for feldspar hydrolysis in the lower pH-dependent range extend from ~10−13 to ~10−7 moles cm−2 sec−1 at temperatures from 25° to 200°C, which is consistent with activation enthalpies for albite and adularia of the order of 20 kcal mole−1. In contrast, the apparent rate constants for the pH-independent rate law range from ~10−16 to ~10−11 moles cm−2 sec−1 at temperatures from 25° to 650°C, which requires an activation enthalpy for adularia of ~ 9 kcal mole−1. These observations are consistent with surface control of reaction rates among minerals and aqueous solutions. The rate-limiting step in the pH-dependent case apparently corresponds at the lower end of the pH scale to breakdown of a protonated configuration of atoms on the surface of the reactant feldspar, but at higher pH the rate is limited by decomposition of an activated surface complex corresponding in stoichiometry to hydrous feldspar. In highly alkaline solutions, an activated complex containing hydroxyl ions apparently controls the rate of feldspar hydrolysis. Nevertheless, near equilibrium, regardless of pH the rate is proportional to the chemical affinity of the overall hydrolysis reaction.
Identification of Protein-Receptor Components Required for the Import of Prealdehyde Dehydrogenase into Rat Liver Mitochondria

Mitochondrial aldehyde dehydrogenase is synthesized as a high-molecular-weight precursor in cytosol and transported into mitochondrial matrix space where it is processed to the mature enzyme. To identify components of the transport machinery on liver mitochondria, anti-idiotypic antibodies against the rabbit anti-prealdehyde dehydrogenase signal peptide antibodies were produced in chicken eggs and rabbit. Both anti-idiotypic antibodies inhibited the import of prealdehyde dehydrogenase (pALDH) into isolated rat liver mitochondria. The rabbit anti-idiotypic antibody could recognize by Western blotting five mitochondrial membrane proteins with apparent molecular weights of 66, 60, 42, 34, and 29 kDa. The anti-idiotypic antibodies were cross-linked to mitochondrial membrane proteins using sulfosuccinimidyl 2-(p-azidosalicylamido)ethyl-1,3'-dithiopropionate which is an iodinatable, heterofunctional, and photoreactive cross-linker. Mitochondrial proteins with apparent molecular weights of 66, 60, and 42 kDa were identified using the chicken antibody. The 66- and 34-kDa proteins were cross-linked to the rabbit antibody as the major components and the 42-kDa protein as a minor one. Antibodies against the 60- and 42-kDa proteins, as well as Fab fragments, inhibited the import of pALDH, suggesting that these proteins are receptor/translocator components for pALDH import.
Seismicity trends and potential for large earthquakes in the Alaska-Aleutian region

The high likelihood of a gap-filling thrust earthquake in the Alaska subduction zone within this decade is indicated by two independent methods: analysis of historic earthquake recurrence data and time-to-failure analysis applied to recent decades of instrumental data. Recent (May 1993) earthquake activity in the Shumagin Islands gap is consistent with previous projections of increases in seismic release, indicating that this segment, along with the Alaska Peninsula segment, is approaching failure. Based on this pattern of accelerating seismic release, we project the occurrence of one or more M ≥ 7.3 earthquakes in the Shumagin-Alaska Peninsula region during 1994–1996. Different segments of the Alaska-Aleutian seismic zone behave differently in the decade or two preceding great earthquakes, some showing acceleration of seismic release (type “A” zones), while others show deceleration (type “D” zones). The largest Alaska-Aleutian earthquakes—in 1957, 1964, and 1965—originated in zones that exhibit type D behavior. Type A zones currently showing accelerating release are the Shumagin, Alaska Peninsula, Delarof, and Kommandorski segments. Time-to-failure analysis suggests that the large earthquakes could occur in these latter zones within the next few years.
Mechanical property characterization of resin cement after aqueous aging with and without cyclic loading.

Abstract Objective . The purpose of this study was to determine changes in flexural properties of resin cement under cyclic loading and aqueous aging. Methods . Panavia F flexural modulus and strength were measured by static loading to failure after 48-h, 31-d, and 60-d aqueous aging at 37 °C with and without cyclic loading at clinical stress levels. Six specimens were used for each experimental condition. Scanning electron microscopy (SEM) was also used to characterize the morphology of the fractured surfaces to potentially identify resin cement components particularly susceptible to degradation under simulated clinical function. Results . A two-factor ANOVA ( p ≤0.05) and Least Significant Difference post hoc test indicated that cyclic loading produced a significant increase in the flexural modulus with no significant effect on the flexural strength. In contrast, aqueous aging time produced a significant decrease in flexural strength with no effect on the flexural modulus. The SEM fracture analysis indicated that resin matrix fracture occurred in static-aqueous specimens; while in the aqueous-cycled specimens, resin matrix fracture occurred in addition to an increasing proportion of filler/resin interface fracture as a result of both increased aqueous aging and increased flexural cycles. Significance . Evidence suggests that after aqueous aging with cyclic loading to simulate resin cement clinical function, initial degradation may be related to breakdown of the filler/resin interface bond. Such breakdown is potentially reflective of slow crack propagation that may contribute to in vivo resin cement cohesive failure.
RELATIONSHIPS OF ENVIRONMENTAL CHARACTERISTICS, FORMALIZED PLANNING, AND ORGANIZATIONAL DESIGN TO PERFORMANCE

An area that so far has been neglected within organizational theory research is the examination of the relationship of characteristics of the environment, formalized planning, and organizational structure, along with their resultant effects on firm performance. This paper examines these relationships based on three environmental dimensions, four design dimensions, and two dimensions of formalized planning used by decision makers within an organization. The results of an empirical investigation suggest that environmental characteristics and organizational design do have an impact on both performance efficiency and performance effectiveness. In addition, interactions of environmental characteristics and organizational design on performance effectiveness were significant.
Redefining outcomes in right congenital diaphragmatic hernia.

Abstract Purpose Available data comparing the management and outcome of right-sided (R-CDH) vs left-sided congenital diaphragmatic hernia (L-CDH) are inconsistent. Large-volume CDH studies are limited by small numbers of R-CDH or are confounded by compilations from multiple institutions with multiple treatment strategies. Consequently, they are underpowered to draw conclusions. To define the behavior and outcomes of R-CDH better, we report the largest single-institution series of R-CDH and ask if factors traditionally linked to poor prognosis in L-CDH were applicable to R-CDH. Methods We reviewed a single institution's experience with 267 consecutive evaluable neonates with unilateral CDH repaired from 1990 to 2006, with specific focus on R-CDH. χ 2 tests were performed for disease-related categorical variables. Two-tailed unpaired t tests were used for continuous variables. Factors associated with morbidity and survival were determined by univariate regression. Statistical significance was set at P Results Forty right-sided (15%) and 227 (85%) left-sided cases of CDH were identified. Prenatal diagnosis was made in 20 right-sided vs 170 left-sided defects (50% vs 75%, P P P P P P = .38), mean time from birth to operation (5.3 vs 4.8 days, P = .80), or presence of cardiac anomalies (15% vs 12%, P = .63). Morbidity persisting beyond 6 months of age was present in 16 of 22 R-CDH survivors compared with 76 of 175 L-CDH survivors (73% vs 43%, P > .05). Among R-CDHs, prenatal diagnosis was the only factor to predict survival by univariate regression ( P P Conclusion Although previous reports suggest that associated anomalies, need for extracorporeal membrane oxygenation, and time to repair can influence L-CDH survival, these data do not support extrapolation to R-CDH survival. Right-sided CDH carries a disproportionately high morbidity and mortality. Prenatal diagnosis was the only factor predictive of R-CDH survival. Morbidity may correlate with use of prosthetic material for R-CDH repair. Right-sided CDH is a unique disease that may require a modified antenatal consultation.
Interaction between superconductivity and magnetism in the pseudoternary system (Lu1−xHox)Rh4B4

Abstract The boundaries between the normal paramagnetic, superconducting and normal magnetically ordered phases in the tetragonal pseudoternary rare earth system (Lu 1− x Ho x )Rh 4 B 4 have been established by means of a.c. magnetic susceptibility measurements to temperatures as low as 0.07 K. The heat capacities of the ternary compounds LuRh 4 B 4 and HoRh 4 B 4 and the pseudoternary compound (Lu 0.5 Ho 0.5 Rh 4 B 4 have been measured from 0.5 K to 36 K. The static magnetic susceptibility and a.c. electrical resistance have been determined between about 1 K and room temperature for the ferromagnetic ternary compound HoRh 4 B 4 .
An error analysis for the hybrid gridding of Texas daily precipitation data

This paper reports the error analysis results for the gridded daily precipitation data over the state of Texas of the United States from January 1, 1901 to December 31, 2000. The Global Daily Climatology Network dataset is used for both the data gridding and error analysis. The station data have been interpolated onto a 0.2° x 0.2° grid which starts at the base point (25°50'N, 106°38'W). The data gridding approach is a hybrid method, which is a blend of two simple methods: inverse distance weighting and nearest station assignment. Our gridding results are compared with those obtained by other gridding methods. The cross-validation method is used for the error analysis. Our error analysis of the interpolated products includes not only the conventional errors, such as the mean bias error, but also the probabilistic distribution of the relative errors of precipitation frequency and the spatial distribution of a major Texas historical storm. The following results have been found: (1) a simple arithmetic average of station data usually overestimates Texas' average precipitation by 2.4 mm per day, (2) the relative error of the precipitation frequency follows a lognormal distribution, and (3) the hybrid gridding data do not have obvious bias and can reasonably display storm-covered areas in Texas. The gridded data and error results are useful for the validation of climate models, calibration of satellite borne remote sensing devices, and numerous agricultural and hydrological applications. The statistical methods of our analysis and some of our results are applicable to other regions of the world. Copyright © 2009 Royal Meteorological Society.
A phenylalanine tRNA gene from Neurospora crassa: conservation of secondary structure involving an intervening sequence

We have isolated and sequenced a tRNAPhe gene from Neurospora crassa. Hybridization analyses suggest that trnaPhe is the only tRNA encoded on the cloned 5 kb DNA fragment. The tRNAPhe gene contains an intervening sequence 16 nucleotides in length located one nucleotide 3' to the anticodon position. The tRNAPhe coding region of Neurospora and yeast are 91% conserved, whereas their intervening sequences are only 50% identical. The pattern of sequence conservation is consistent with a proposed secondary structure for the tRNA precursor in which the anticodon is base paired with the middle of the intervening sequence and the splice points are located in adjacent single-stranded loops. The DNA sequence following the tRNAPhe coding region is similar to sequences following other genes transcribed by RNA polymerase III in that it is AT-rich and includes a tract of A residues in the coding strand. In contrast, the sequence preceding the Neurospora tRNAPhe coding region does not resemble sequences preceding other sequenced tRNA genes.
A Profile for Predicting Attrition from Exercise in Older Adults

The purpose of this study was to determine a profile for predicting attrition among older adults involved in a 12-month exercise program. The parent study was a single-blinded randomized controlled trial. The study took place between 2006 and 2009 within a university setting. Older adults (N = 179) completed baseline assessments of functional performance and psychosocial measures. Participants who were randomized, elected to receive treatment, and did not complete the exercise program were considered “dropouts” (n = 35). Those who completed the program (n = 144) were classified as “completers.” A latent profile analysis revealed two distinct patterns of memory complaints, self-efficacy to overcome barriers to exercise, balance performance, and stair performance. Dropouts were nearly twice as likely to be members of the profile that exhibited a higher degree of memory complaints, lower self-efficacy for overcoming exercise barriers, poorer single leg balance, and longer times to walk down stairs. The results provide an initial validation of a profile for discriminating between “dropouts” and “completers,” one that may have considerable utility for screening older adults prior to study entry.
High Avidity CD8+ T Cells Efficiently Eliminate Motile HIV-Infected Targets and Execute a Locally Focused Program of Anti-Viral Function

The dissemination of HIV from an initial site of infection is facilitated by motile HIV-infected CD4+ T-cells. However, the impact of infected target cell migration on antigen recognition by HIV-specific CD8+ T-cells is unclear. Using a 3D in vitro model of tissue, we visualized dynamic interactions between HIV-infected or peptide-pulsed CD4+ T-cells and HIV-specific CD8+ T-cells. CTLs engaged motile HIV-infected targets, but ∼50% of targets broke contact and escaped. In contrast, immobilized target cells were readily killed, indicating target motility directly inhibits CD8+ T-cell function. Strong calcium signals occurred in CTLs killing a motile target but calcium signaling was weak or absent in CTLs which permitted target escape. Neutralization of adhesion receptors LFA-1 and CD58 inhibited CD8+ T-cell function within the 3D matrix, demonstrating that efficient motile target lysis as dependent on adhesive engagement of targets. Antigen sensitivity (a convolution of antigen density, TCR avidity and CD8 coreceptor binding) is also critical for target recognition. We modulated this parameter (known as functional avidity but referred to here as “avidity” for the sake of simplicity) by exploiting common HIV escape mutations and measured their impact on CTL function at the single-cell level. Targets pulsed with low avidity mutant antigens frequently escaped while CTLs killed targets bearing high avidity antigen with near-perfect efficiency. CTLs engaged, arrested, and killed an initial target bearing high avidity antigen within minutes, but serial killing was surprisingly rare. CD8 cells remained committed to their initial dead target for hours, accumulating TCR signals that sustained secretion of soluble antiviral factors. These data indicate that high-avidity CD8+ T-cells execute an antiviral program in the precise location where antigen has been sensed: CTL effector functions are spatiotemporally coordinated with an early lytic phase followed by a sustained stationary secretory phase to control local viral infection.
Organic photovoltaic materials: squarylium and cyanine-TCNQ dyes

The photovoltaic properties of Schottky barrier sandwich cells consisting of sublimed and solution-cast thin films of selected squarylium (bis-anilino derivatives of cyclobuta-l,3-diene-2,4-dione) and cyanine-tetracyanoquinodimethanide( TCNQ) dyes have been measured. For hydroxy squarylium (OHSq), maximum power conversion efficiencies (η) were 0.2% for 850-nm light (1 mW/cm2): 0.05% for 633-nm light (94 mW/cm2); 0.06% for "white" light (21 mW/cm2): 0.15% for low intensity (0.14 mW/cm2) simulated AMO light (sunlight under outer space conditions), and 0.02% for high intensity (140 mW/cm2) AMO light. Efficiencies of selected OHSq cells were observed to increase fivefold when the cells were doped with bromine or 1-phenyl-3-p-N,N-diethylaminostyryl-5-p-N,-N-diethylaminophenyl-Δ 2-pyrazoline (DEASP), e.g., 0.05 to 0.23% (Br): 0.004 to 0.021% (DEASP). The efficiency of a solution-cast cell of amorphous 2,2′-dicarbocyanine-TCNQ was 0.02% when 933-nm light (approximately 1 mW/cm2) was used. Amorphous solid solutions of 1,1′- diethyl-2,2′-dicarbocyanine- and oxa-2,2′-dicarbocyanine-TCNQ salts were also tested. The effects of various material and device properties on the performancoef organic photovoltaic cells are discussed, and it is proposed that organic solar cells having efficiencies of one percent or more can be made by using existing technologies.
Noise estimation and reduction on five medical liquid-crystal displays

— Liquid-crystal displays (LCDs) are replacing cathode-ray tube (CRT) displays as primary diagnostic viewing devices in clinics. They exhibit higher spatial noise than CRTs, which can interfere with diagnosis and reduce the efficiency especially when subtle abnormalities are presented. A study by the authors on LCD spatial noise has recently been reported. A high-quality CCD camera was used to acquire images from the LCD. Noise properties were estimated from the digital-camera images. Then, an error-diffusion-based operation was applied to reduce the display spatial noise. This paper presents the noise estimation and reduction results on five different medical-grade LCDs using the same study protocol. These five different LCDs vary in terms of matrix size, pixel size, pixel structure, and vendors. The purpose of this work is to demonstrate that the LCD spatial-noise estimation and reduction scheme proposed earlier by the authors is valid, robust, and necessary for various medicalgrade LCDs used in clinics today.
Characteristics of λp4, a λ derivative containing 9% excess DNA

Abstract In order to study virion morphogenesis in phage λ, we are synthesizing prophage genomes which are longer than normal and investigating what happens when they are induced. Our minor goal is to determine the upper limit to the quantity of DNA that can be incorporated into a phage head. Our major goal is to investigate DNA cutting, capsid formation, and DNA incorporation into the capsid when the genome is too long to be contained in the normal phage head. In the first application of this approach, we have constructed a prophage genome containing 9% excess DNA. Upon induction, this genome produces viable particles whose density and rate of heat inactivation indicate they contain the complete genome in a normal capsid. However, these phage have a reduced burst size which is attributable to the physical size of the genome.
A novel brainstem tumor model: functional and histopathological characterization

Diffuse pontine gliomas remain a challenging and frustrating disease to treat. The survival rates for these high-grade brainstem tumors (BSTs) is dismal and optimal therapy has yet to be determined. The development of a satisfactory brainstem tumor model is necessary for testing new therapeutic paradigms that may prolong survival. We report the surgical technique, functional testing, and histopathological features of a novel brainstem tumor model in rats. Female Fischer 344 rats (n=45) were randomized to receive an injection of either 3 μl of 9L gliosarcoma cells (100,000 cells, n=), 3 μl of F98 glioma cells (100,000 cells, n=10), or 3 μl of medium (Dulbecco’s modified eagle medium) into the pontine tegmentum. Using a cannulated guide screw system, implanted in the skull of the animal, we injected each group at coordinates 1.4 mm right of the sagittal and 1.0 mm anterior of the lambdoid sutures, at a depth of 7.0 mm from the dura. The head was positioned 5° from horizontal before injection. The rats were post-operatively evaluated for neurological deficits using an automated test. Kaplan–Meier curves were generated for survival and disease progression, and brains were processed postmortem for histopathology. 9L and F98 tumor cells grew in 100% of animals injected and resulted in a statistically significant mean onset of hemiparesis of 16.5±0.56 days (P=0.001, log-rank test), compared to animals in the control group which lacked neurological deficits by day 60. The animals with tumor cells implanted demonstrated significant deterioration of function on the automated rod testing. Animals in the control group showed no functional or pathological signs of tumor. Progression to hemiparesis was consistent in all tumor-injected animals, with predictable onset of symptoms occurring approximately 17 days post-surgery. The histopathological characteristics of the 9L and F98 BSTs were comparable to those of aggressive human BSTs. The establishment of this animal tumor model will facilitate the testing of new therapeutic paradigms for the treatment of BSTs.
An assessment of sinus quality of life and pulmonary function in children with cystic fibrosis.

BackgroundTreatment of patents with cystic fibrosis (CF) is primarily directed at the lungs. However, there is a growing feeling that the status of the sinuses may have a profound influence on the status of the lungs in these patients. A number of investigators have demonstrated a relationship among coexisting rhinitis, sinusitis, other upper airway conditions, and lung disease. Several studies have shown that treatment and resolution of sinusitis results in an improvement in a number of pulmonary conditions. We hypothesize that pulmonary function test scores will be lower in patients with CF with more severe sinusitis.MethodsConsecutive CF patients were asked to complete a sinus-specific quality-of-life instrument, the 16-item Sino-Nasal Outcome Test (SNOT-16), and these scores, were compared to FEV1 scores.ResultsUnivariate analysis revealed a significant correlation between SNOT-16 and FEV1 in patients under the age of 12. There was a trend toward significance in the older children and evaluation of th...
New classification of low-grade lymphoma

The problem of morphologic classification of the indolent non-Hodgkin's lymphomas has been addressed by the National Cancer Institute Working Formulation, the International Lymphoma Study Group, and other groups. The criteria for classification have expanded to include biologic and laboratory parameters. Clinical aspects are important, because diagnostic categories that obscure discrete entities, such as mucosa-associated B-cell lymphoma could adversely affect therapy. This and other indolent non-Hodgkin's lymphomas and mantle-cell lymphoma, which has been provisionally included among them, are reviewed. Variations in nomenclature, immunohistochemical and molecular characteristics, and whenever possible, prognosis and clinical outcome are described. The need for further correlation with clinical outcome of these entities is noted.
NaLa(MoO4)2 as a laser host material

Crystallographic and optical properties of NaLa(${\mathrm{MoO}}_{4}$${)}_{2}$ are presented. The positions of the Stark levels are reported for the [LS]J manifolds of ${\mathrm{Nd}}^{3+}$ and ${\mathrm{Er}}^{3+}$ up to the absorption edge in this host material. A least-squares fit to the data was performed to obtain the crystal-field parameters. For ${\mathrm{Nd}}^{3+}$ the following crystal-field parameters were obtained: ${\mathit{B}}_{20}$=519, ${\mathit{B}}_{40}$=-695, ${\mathit{B}}_{44}$=964, ${\mathit{B}}_{60}$=-190, and ${\mathit{B}}_{64}$=673+i384 ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$, with a root-mean-square (rms) deviation of 7.7 ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$. For ${\mathrm{Er}}^{3+}$ we obtained ${\mathit{B}}_{20}$=422, ${\mathit{B}}_{40}$=-507, ${\mathit{B}}_{44}$=839, ${\mathit{B}}_{60}$=-116, and ${\mathit{B}}_{64}$=409+i158 ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$, with a rms deviation of 4.8 ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$. Intensity calculations based on fits to the experimental data yield line-to-line and multiplet branching ratios. The results of this investigation indicate that ${\mathrm{Er}}^{3+}$:NaLa(${\mathrm{MoO}}_{4}$${)}_{2}$ and ${\mathrm{Nd}}^{3+}$:NaLa(${\mathrm{MoO}}_{4}$${)}_{2}$ show promise as diode-pumped laser materials.
Deposition of smooth, oriented diamond films using microwave plasma chemical vapor deposition

Abstract The use of low pressure and high gas flow conditions in a microwave plasma diamond chemical vapor deposition reactor resulted in films with small grain size and with a (110) preferred orientation on silicon substrates. The diamond films were deposited at 23 Torr total pressure, with gas composition of 1% CH 4 in H 2 , and total gas flow rate of 25–800 standard cm 3 min −1 . An intermediate layer of microcrystalline diamond was also effective in reducing the grain size and increasing the degree of preferred orientation. Flow modeling of the reactor showed a qualitative change in convective flow pattern over our range of experimental conditions. Recirculation vortices formed at the low flow conditions, but mostly disappeared at the higher gas flow rates. The modest increase in deposition rate which we observed in consistent with the loss of vortex structure. The results are compared with those of a previous study of diamond films deposited at 40 Torr.
Brain‐Derived Neurotrophic Factor in Neuronal Survival and Behavior‐Related Plasticity

Neurotrophins are critical to the development and maintenance of the mammalian central nervous system. Among them is brain-derived neurotrophic factor (BDNF), whose synthesis and release is targeted by activation of glutamate receptors. Perturbation of this process probably underlies neurodegenerative and psychiatric disorders. A naturally occurring variation in humans, in the form of a common single-nucleotide polymorphism in the pro region of the polypeptide at codon 66 (Val66-->Met), affects processing of the pro-BDNF polypeptide and its activation-dependent release. This variant is associated with differences in the volume of the hippocampal formation and with anxiety and depression-related phenotypes. Convergent findings supporting a role for BDNF in alterations to hippocampal structure and behavior are found in a "humanized" BDNF transgenic mouse. Also, recent human genetic studies have supported a role of BDNF signaling in addictive behaviors by allele-, genotype-, and haplotype-based association of the TrkB gene, which encodes the cognate receptor for BDNF, with alcohol dependence. A better understanding of the influence of BDNF-mediated pathways in cell survival and plasticity will aid in developing new approaches to restoring normal function in disease states.
Neonatal hematocrit and maternal glycemic control in insulin-dependent diabetes

We hypothesized that in infants of diabetic women neonatal hematocrit would correlate with third-trimester maternal glycemic control. Neonatal hematocrit correlated with the maternal total glycosylated hemoglobin level at delivery ( r =0.36; p
Spectroscopic measurement of diffuse reflectance for enhanced detection of bladder carcinoma

Abstract Objectives. To assess the diagnostic potential of diffuse reflectance spectroscopy for the detection of bladder carcinoma during cystoscopy. Our hypothesis is that neovasculature in neoplastic (dysplastic and malignant) regions will lead to a blood absorption “signature” that is different from that of normal tissue. Methods. Diffuse reflectance measurements have been performed in 14 patients undergoing mucosal biopsies or transurethral resection of a bladder tumor. A quartz optical fiber was advanced through the working channel of a cystoscope and placed in gentle contact with the bladder surface. A standard cystoscopy xenon light source was used for illumination and the reflectance spectra were recorded using an optical multichannel analyzer (OMA) system. From the spectra, the relative concentrations of hemoglobin (Hb), oxyhemoglobin (HbO 2 ), oxygen saturation (HbO 2 %), and the total amount of blood (arbitrary units) were calculated to assess their usefulness in differentiating between neoplastic and benign bladder areas. Results. The spectra of 26 bladder areas (9 malignant areas including 4 carcinomata in situ, 2 dysplastic lesions, and 15 benign areas) have been analyzed. Only the total amount of blood was a useful parameter for the differentiation between neoplastic and benign bladder areas. The sensitivity, specificity, and positive and negative predictive values of this method for neoplastic tissue were found to be 91%, 60%, 63%, and 90%, respectively. Conclusions. The measurement of diffuse reflectance is a fast, simple, and noninvasive method which allows in vivo determination of bladder blood perfusion. The total blood concentration was increased in neoplastic bladder tissue, making it a tool for tissue diagnosis. The relatively low specificity is a result of inflammatory areas also exhibiting an increased total blood concentration. This pilot study encourages further studies to assess the usefulness of reflectance measurements for enhanced detection of bladder cancer.
Mitochondrial cytochrome c release in apoptosis occurs upstream of DEVD-specific caspase activation and independently of mitochondrial transmembrane depolarization

Mitochondrial cytochrome c, which functions as an electron carrier in the respiratory chain, translocates to the cytosol in cells undergoing apoptosis, where it participates in the activation of DEVD-specific caspases. The apoptosis inhibitors Bcl-2 or Bcl-xL prevent the efflux of cytochrome c from mitochondria. The mechanism responsible for the release of cytochrome c from mitochondria during apoptosis is unknown. Here, we report that cytochrome c release from mitochondria is an early event in the apoptotic process induced by UVB irradiation or staurosporine treatment in CEM or HeLa cells, preceding or at the time of DEVD-specific caspase activation and substrate cleavage. A reduction in mitochondrial transmembrane potential (Deltapsim) occurred considerably later than cytochrome c translocation and caspase activation, and was not necessary for DNA fragmentation. Although zVAD-fmk substantially blocked caspase activity, a reduction in Deltapsim and cell death, it failed to prevent the passage of cytochrome c from mitochondria to the cytosol. Thus the translocation of cytochrome c from mitochondria to cytosol does not require a mitochondrial transmembrane depolarization.
Nuclear structure functions for χ⩾1

Abstract A classification of the different contributions to nuclear structure functions is presented. Using a relativistic description of the nucleus, we predict the behavior of the structure functions of different nuclei for values of the nucleon Bjorken variable χ ⩾1.
Concerning the Extents of Nucleophilic Participation in Solvolyses of p-Methoxybenzyl Halides

The solvolyses of p-methoxybenzyl chloride (1) in 39 solvents are well correlated using an extended form of the Grunwald–Winstein equation; a claim that nucleophilic participation is greater than in the solvolyses of the corresponding bromide 2 is discussed.
Identification of integrated hepatitis B virus DNA and expression of viral RNA in an HBsAg-producing human hepatocellular carcinoma cell line

Alexander and co-workers1 have developed a tissue culture cell line (PLC/PRF/5) from a primary hepatocellular carcinoma of a Mozambican male with a positive serum for hepatitis B virus surface antigen (HBsAg). This cell line produces and secretes HBsAg but no other known viral protein1–3. PLC/PRF/5 therefore contains at least part of the hepatitis B virus (HBV) genome in functional form. The 42-nm, spherical Dane particle in human serum is thought to represent the complete infectious agent of HBV4. The core of this particle contains circular double-stranded DNA in which one strand is ‘nicked’ (complete but not covalently closed) and the other strand is incomplete (lacking 15–45% of its sequence complement)4,5. Four proteins have been associated with the HBsAg, core antigen (HBcAg), e antigen and a viral DNA polymerase4. Several groups have now cloned Dane particle DNA in Escherichia coli6–10, and both restriction maps and a complete DNA sequence have been determined. Various studies suggest that there is sequence heterogeneity in Dane particle DNA isolated from patients expressing the same or different viral subtypes, as well as sequence variation in different clones of Dane particle DNA obtained from a given individual10,11. Other studies12,13 have reported HBV DNA sequences in DNA from liver cancer tissue. In none of these cases was viral DNA reported to be integrated into the host cell genome. With the improvement in techniques for characterizing viral DNA molecules, we have begun to analyse HBV genes and their expression in the PLC/PRF/5 cell line by molecular hybridization of cellular DNA and RNA to cloned 32P-labelled plasmid HBV DNA. We now present evidence in PLC/PRF/5 cells for integration of HBV DNA into the host genome and expression of three RNA molecules containing HBV-specific sequences. These findings are consistent with observations in several animal virus models in which integrated viral DNA is found during oncogenic transformation.
Dynamics of Short-Term Univariate Forecast Error Covariances

Abstract The covariance equation based on second-order closure for dynamics governed by a general scalar nonlinear partial differential equation (PDE) is studied. If the governing dynamics involve n space dimensions, then the covariance equation is a PDE in 2n space dimensions. Solving this equation for n = 3 is therefore computationally infeasible. This is a hindrance to stochastic-dynamic prediction as well as to novel methods of data assimilation based on the Kalman filter. It is shown that the covariance equation can be solved approximately, to any desired accuracy, by solving instead an auxiliary system of PDEs in just n dimensions. The first of these is a dynamical equation for the variance field. Successive equations describe, to increasingly high order, the dynamics of the shape of either the covariance function or the correlation function for points separated by small distances. The second-order equation, for instance, describes the evolution of the correlation length (turbulent microscale) field...
Endogenous money or sticky prices?—comment on monetary non-neutrality and inflation dynamics

Abstract We show that the highly persistent inflation dynamics and its lead-lag relationship with output can be explained by a standard flexible price RBC model augmented with endogenous monetary policy. Endogenous monetary policy acting upon the illusion that prices are sticky and money is effective can create price movements that appear to indicate price stickiness, although there is none in the economy.
The effect of metribuzin interaction with potato viruses X and Y on potato foliage, yield and grade.

Foliar treatment of potato (Solanum tuberosum L.) with metribuzin at 0.57–1.0 lb/A caused a necrotic reaction in leaflets of plants infected with potato virus Y (PVY), but not in plants infected with potato virus X (PVX) or potato leafroll virus. Necrosis symptoms resulting from metribuzin-PVY interaction were distinct from symptoms of either PVY infection or of metribuzin injury. This reaction was similar in the Russet Burbank, Lemhi Russet, and Pioneer cultivars. Russet Burbank infected with PVY and PVX, alone or in combination, was treated with metribuzin to study herbicidevirus interaction effects on yield. Secondary PVY infection alone caused a 57% yield reduction, and when combined with PVX caused a 71% yield reduction. Although leaflet necrosis was induced by the metribuzin-PVY combination, there was no significant yield interaction. Results suggest that post-emergence application of metribuzin can be used as an aid for detecting and removing potato virus Y infected plants from potato seed fields
The effect of cimetidine on hepatic drug elimination in cirrhosis

Both cimetidine therapy and cirrhosis individually interfere with normal elimination of various drugs. Cimetidine is often prescribed in patients with cirrhosis but there is incomplete data on its effect on drug elimination in cirrhotics. The purpose of this study was to address this issue. Eight stable cirrhotics were studied prior to and following 7 days of cimetidine administration, (300 mg orally q.i.d.). Chlordiazepoxide (Librium), which is eliminated by the liver after demethylation, and indocyanine green, which is removed by the liver without biotransformation, were used as probes. Consistent with the concept that cimetidine interferes with drug metabolism by inhibiting microsomal oxidation, chlordiazepoxide clearance in the cirrhotics was inhibited by cimetidine (p less than 0.05), but indocyanine green clearance was unaffected. As shown by us previously (Roberts, R. K. et al., Gastroenterology 1978; 75:479-485), untreated cirrhotics had substantially lower chlordiazepoxide clearance than did controls. The inhibitory effect of cimetidine on chlordiazepoxide clearance was less in cirrhotics than in controls (p less than 0.05). In all subjects, there was excellent correlation between initial clearance and magnitude of depression in clearance after cimetidine, i.e., the larger the initial clearance, the larger the change (r = 0.97, p less than 0.0001). Forty-eight hours after stopping cimetidine, chlordiazepoxide clearance returned to baseline in cirrhotics and controls. Our data demonstrate that cimetidine and cirrhosis may act additively to impair drug metabolism. This effect of cimetidine on chlordiazepoxide clearance is smaller in cirrhotics than in controls, but, because of impaired initial drug elimination in cirrhosis, it may result in adverse clinical effects.
Effect of Film-Cooling Hole Location on Turbulator Heat Transfer Enhancement in Turbine Blade Internal Air-Cooling Circuits

Numerical results demonstrating the effect of film-cooling hole placement on turbulator heat transfer effectiveness in internal convective cooling air circuits of turbine blades in high-performance gas turbine engines is presented for a two-dimensional model problem. Of particular interest will be the performance of a new turbulence modeling formalism similar to large-eddy simulation (LES) but employing subgrid-scale models constructed from nonlinear discrete dynamical systems, and not requiring filtering of the resolved-scale governing equations. Computed results for temperature distribution, flow streamlines, pressure coefficient and heat transfer Stanton number are compared for three different cooling hole/turbulator configurations, and turbulence kinetic energy is compared with results from a standard k-e model.Copyright © 1999 by ASME
Effects of isolation and grouping on guinea pigs

Guinea pigs spent 80 days in isolation or same-sex groups beginning either immediately after weaning or in adulthood. Isolated animals were more active in a cross maze, but not in an open field. No group of animals preferred a goal guinea pig in a four-choice test. Males isolated at weaning meeting another such male were more aggressive than males in isolated-grouped or grouped-grouped encounters, but did not make more nonaggressive contacts. Males isolated in adulthood meeting other such males exhibited more nonaggressive behavior, but not more fighting. Use of “gregariousness” as a unitary concept is questioned.
Ethics in Computing

The increasing dependence of critical infrastructures on computer hardware and software has given rise to unanticipated ethical, social, and legal complications [1]. Transportation systems, the power grid, and emergency services, and financial networks all rely on a vast amount of information from diverse sources. Protection of the integrity, confidentiality, and privacy of this information often results in ethical dilemmas, in particular in times of crisis.
Genomic responses to abnormal gene dosage: the X chromosome improved on a common strategy.

Mechanisms to guard genomic integrity are critical to ensuring the welfare and survival of an organism. Disruptions of genomic integrity can result in aneuploidy, a large-scale genomic imbalance caused by either extra or missing whole chromosomes (chromosomal aneuploidy) or chromosome segments (segmental aneuploidy). A change in dosage of a single gene may not compromise the well-being of an organism, but the combined altered dosage of many genes due to aneuploidy disturbs the overall balance of gene expression networks, resulting in decreased fitness and mortality [1],[2]. Chromosomal aneuploidy is a common cause of birth defects—Down syndrome is caused by an extra copy of Chromosome 21, and Turner syndrome by a single copy of the X chromosome in females. Furthermore, methods that detect segmental aneuploidy have uncovered small deletions or duplications of the genome in association with many disorders, such as mental retardation. Chromosomal and segmental aneuploidies are also frequent in cancer cells in which changes in copy number paradoxically increase cell fitness but are unfavorable to survival of the organism. A fundamental issue in biology and medicine is to understand the effects of aneuploidy on gene expression and the mechanisms that alleviate aneuploidy-induced imbalance of the genome. Chromosomal aneuploidy is caused by non-disjunction of chromosomes in meiosis or mitosis, while segmental aneuploidy involves breakage and ligation of DNA. In contrast, the sex chromosomes provide an example of a naturally occurring “aneuploidy” caused by the evolution of a specific set of chromosomes for sex determination that often differ in their copy number between males and females. For example, in mammals and in flies, females have two X chromosomes and males have one X chromosome and a Y chromosome, resulting in X monosomy in males. How does a cell or an organism respond to such different types of aneuploidy, abnormal or natural? It turns out that the overall expression level of a given gene is not necessarily in direct relation to the copy number. Unique strategies have evolved to deal with abnormal gene dosage to alleviate the effects of aneuploidy by dampening changes in expression levels. What's more, the X chromosome has evolved sophisticated mechanisms to achieve complete dosage compensation, not surprisingly, since the copy number difference between males and females has been evolving for a long time.
On implementing security at the transport layer

We design a framework that implements security at the TCP layer to meet the necessity for a practical and truly end-to-end security solution. We call our framework TCPsec. TCPsec is a security extension to TCP and implemented in the kernel. Applications may use TCPsec through regular TCP sockets by setting special socket options. TCPsec uses a Secure Socket Layer (SSL)-like handshake to set up a secure session. It is interoperable with Network Address Translators. We implement TCPsec in the FreeBSD 4.7 kernel and evaluate its performance. Our implementation and evaluation show that TCPsec incurs only a modest overhead as compared to TCP and performs competitively with SSL. We also provide a formal verification of our protocol state machine.
Isolation and identification of eight microsatellite loci in the Cherokee darter (Etheostoma scotti) and their variability in other members of the genera Etheostoma, Ammocrypta, and Percina

The Cherokee darter Etheostoma scotti is a federally threatened fish endemic to the Etowah River system of northwest Georgia. In order to analyse the population structure and genetic diversity of this fish, eight tetranucleotide microsatellite genetic markers were developed. The marker set was applied to 13 additional darter species to test cross-species amplification and polymorphism. Successful amplification was obtained for all eight loci in each of the 13 other species of darters, with between seven and eight polymorphic loci per species.
A novel approach in the assessment of polymeric film formation and film adhesion on different pharmaceutical solid substrates.

The purpose of this study was to evaluate the nature of film formation on tablets with different compositions, using confocal laser scanning microscopy (CLSM), and to measure film adhesion via the application of a novel “magnet probe test”. Three excipients, microcrystalline cellulose (MCC), spray-dried lactose monohydrate, and dibasic calcium phosphate dihydrate, were individually blended with 0.5% magnesium stearate, as a lubricant, and 2.5% tetracycline HCl, as a fluorescent marker, and were compressed using a Carver press. Tablets were coated with a solution consisting of 7% hydroxypropyl methylcellulose (HPMC) phthalate (HP-55), and 0.5% cetyl alcohl in acetone and isopropanol (11:9). The nature of polymer interaction with the tablets and coating was evaluated using CLSM and a designed magnet probe test. CLSM images clearly showed coating efficiency, thickness, and uniformity of film formation, and the extent of drug migration into the film at the coating interfaces of tablets. Among the excipients, MCC demonstrated the best interface for both film formation and uniformity in thickness relative to lactose monohydrate and dibasic calcium phosphate dihydrate. The detachment force of the coating layers from the tablet surfaces, as measured with the developed magnet probe test, was in the order of MCC>lactose monohydrate>dibasic calcium phosphate dihydrate. It was also shown that the designed magnet probe test provides reliable and reproducible results when used for measurement of film adhesion and bonding strength.