cssi/SciSciGPT-SciSciNet huggingface dataset:
Structure of the lysozyme from bacteriophage T4: An electron density map at 2.4 Å resolution

Abstract The three-dimensional structure of the lysozyme from bacteriophage T4 has been determined from a 2.4 A resolution electron density map. The map, determined using isomorphous replacement and anomalous scattering differences from platinum and mercury-substituted crystals, reveals the approximate conformation of the molecule unambiguously. Details of the structure determination are presented and the conformation of the molecule is described in detail. The observed properties of those mutant lysozymes for which the changes in the amino acid sequence have been determined are discussed in the light of the three-dimensional structure. In most cases the behavior of the mutant lysozymes can be easily rationalized, but there are a few instances where this is not so.
An Investigation of Carbon−Fluorine Bond Functionalization. Versatile Reactivity of Tungsten(II) Fluoride Carbonyl Metallacycles with Alkynes

Metal-assisted functionalization of aromatic fluorocarbons is reported. Sequential carbon−fluorine oxidative addition and migratory insertion with electron-deficient alkynes are employed to construct novel tungsten(II) η2-vinyl complexes in which net replacement of an aromatic carbon−fluorine bond by a carbon−carbon bond has ensued. A competitive reaction involving the formation of four-electron donor alkyne complexes is favored for electron-rich alkynes. Evidence suggests a two-electron donor alkyne complex may serve as a common intermediate in these transformations, which could either participate in the migratory insertion reaction or lose carbon monoxide to generate the four-electron donor alkyne complex. The observed partitioning of products appears to be controlled by the electronic profile of the coordinated alkyne as well as the nucleophilicity of the migrating aryl group. The migratory insertion reaction is regioselective for 1-phenyl-1-propyne with the insertion taking place at the phenyl-substit...
Effect of Peanut Hull and Pine Chip Biochar on Soil Nutrients, Corn Nutrient Status, and Yield

Pyrolysis is the anaerobic thermal conversion of biomass for energy production. It offers an option of returning carbon and nutrients to the soil while producing energy. The Ultisols in the southeastern United States have inherently low soil organic carbon and fertility, and may benefit from the addition ofbiochar from pyrolysis. Our objectives were to evaluate the effect ofpeanut hull and pine chip biochars on soil nutrients, corn (Zea mays L.) nutrient status and yield in a Kandiudult for two growing seasons (2006 and 2007). Experiments for each biochar source were conducted as completely randomized designs with the biochar applied at 0, 11, and 22 Mg ha -1 with and without N fertilizer. Nitrogen in the peanut hull biochar (209 kg ha -1 at 11 Mg ha -1 rate) was not available during the study based on corn tissue concentrations. The peanut hull biochar linearly increased Mehlich I K, Ca, and Mg in the surface soil (0-15 cm). The increased available K was reflected in the plant tissue analysis at corn stage R1 in 2006, but not in 2007. Pine chip biochar decreased soil pH, but had no effect on other nutrients except Mehlich I Ca. In the peanut hull biochar experiment, grain yields decreased at the 22 Mg ha -1 rate in the fertilized treatments. In the pine chip biochar experiment, grain yields decreased linearly with application rate in 2006, but this did not persist in 2007. Overall yield responses to biochar were smaller than expected based on previous studies.
Deterministic design of ultrahigh Q and small mode volume photonic crystal nanobeam cavity

A deterministic design of an ultrahigh Q, subwavelength mode volume, photonic crystal nanobeam cavity, operating at the target frequency, is proposed and experimentally demonstrated. Nonlinear bistability is observed in such nanobeam cavities fabricated in Si at very low pump powers.
A Second Moment Approach to Probabilistic IRR Using Taylor Series

This article presents a practical approach for computing the internal rate of return (IRR) of stochastic cash flows. The mean and variance of the distribution of the IRR are derived by a second-moment approach using the means, variances, and correlations of the costs and returns in a cash layout. Programmed as an add-in function, the second-moment algorithm was applied to three examples in the literature and the accuracy of the second-moment method was compared with more sophisticated, computationally intensive methods. The comparison indicates that the second-moment approach can serve as a quick and viable tool for probabilistic IRR analysis.
Statin use is associated with a reduced risk of fibrosis progression in chronic hepatitis C.

Background & Aims Therapies that slow fibrosis progression in chronic liver disease are needed. Animal models have demonstrated that statins prevent the progression of hepatic fibrosis, but human data is lacking so far. We evaluated the association between statins and fibrosis progression in the HALT-C trial cohort. Methods Subjects with chronic hepatitis C (CHC) and advanced hepatic fibrosis underwent serial liver biopsies over 3.5years. The primary outcome was a ⩾2-point increase in the Ishak fibrosis score on at least one of two serial biopsies. We used complementary log-log regression analysis to assess the association between statins and fibrosis progression among subjects without baseline cirrhosis. Results Fibrosis progression occurred in 3/29 (10%) statin users and 145/514 (29%) non-users. The unadjusted hazard ratio (HR) for fibrosis progression among statin users compared to non-users was 0.32 (95% CI 0.10–0.99). This association remained significant after adjusting for established predictors of histological outcome, including body mass index, platelets and hepatic steatosis (adjusted HR 0.31; 95% CI 0.10–0.97). The mean change in Ishak fibrosis score over the 3.5year study period was −0.34 (SE 0.18) for statin users compared to +0.42 (SE 0.07) for non-users ( p =0.006, after adjustment for baseline fibrosis score). Conclusions Statin use is associated with a reduced risk of fibrosis progression in advanced CHC. Our findings suggest a potential role for statins in preventing liver disease progression.
Delay in brain growth induced by alcohol in artificially reared rat pups

The effect of alcohol on body and brain growth of the neonatal rat was examined. An artificial rearing procedure was used to administer a milk formula containing 2.8% alcohol to rat pups during days 4-10 postpartum. Mean blood alcohol levels taken at hourly intervals between feelings at the end of the second day of exposure ranged between 151 and 163 mg/dl. Body growth in both groups of artificially reared pups was similar to that of the suckle control pups. Gross measurements indicated that while alcohol exposure did not arrest body growth, it did arrest several parameters of brain growth. There were deficits in brain weight and volume and in the brain weight to body weight ratio. Furthermore, there were sex-related differences. The brain weight to body weight ratio was significantly decreased in females and there was also a trend toward a greater deficit in brain volume as well. However, deficits in gross measures were not reflected in the development of the hippocampal formation. Areal measurements of the hippocampus and dentate gyrus failed to indicate any differential effects on the growth of the pyramidal and granule cell layers, or their dendritic fields and corresponding Timm-stained sublaminae, due to the alcohol exposure. These data suggest that the blood alcohol concentrations reached in the present study may be near the threshold dose for producing deficits in brain growth, and that the females have a lower threshold than the males.
Supporting ease-of-use and user control: desired features and structure of web-based online IR systems

The emergence of Web-based IR systems calls for the need to support ease-of-use as well as user control. This study attempts to investigate users' perceptions of ease-of-use versus user control, and desired functionalities as well as desired interface structure of online IR systems in supporting both ease-of-use and user control. Forty subjects who had an opportunity to learn and use five online databases participated in the study. Multiple methods were employed to collect data. The qualitative and quantitative analysis of the data show that users consider both ease-of-use and user control are essential for effective retrieval. The results are discussed within the context of a model of optimal support for ease-of-use and user control, particularly, emphasizing on the balance between system role and user involvement in achieving various IR sub-tasks.
Optimization of shale gas field development using direct search techniques and reduced-physics models

Abstract The economics of oil and gas field development can be improved significantly by using computational optimization to guide operations. In this work, we present a general framework for applying optimization to the development of shale gas reservoirs. Starting with a detailed three-dimensional full-physics simulation model, which includes heterogeneous geology, highly resolved fracture networks, dual-porosity, dual-permeability regions, and gas desorption, the approach first entails the generation of a much simpler, and much more computationally efficient, reduced-physics surrogate model. This reduced-physics model is tuned using a procedure akin to history matching to provide results in close agreement with the full-physics model. The surrogate model is then used for field development optimization. During the course of the optimization, the surrogate model is periodically ‘retrained’ to maintain agreement with the full-physics representation. In the optimizations considered here, we seek to determine the optimal locations, lengths, and number of fracture stages for a set of horizontal wells. A direct search optimization procedure (generalized pattern search) is applied. In two examples, involving models with properties representative of the Barnett Shale, optimization is shown to provide field development scenarios with net present values that are considerably higher than those of base case designs. In addition, speed-ups of about a factor of 100 are achieved through the use of the surrogate modeling procedure.
Inhibitors of Protein Phosphatase 1 and 2A Differentially Regulate the Expression of Inducible Nitric-oxide Synthase in Rat Astrocytes and Macrophages

Nitric oxide produced by inducible nitric-oxide synthase (iNOS) in different cells including brain cells in response to proinflammatory cytokines plays an important role in the pathophysiology of stroke and other neurodegenerative diseases. The present study underlines the importance of protein phosphatase (PP) 1 and 2A in the regulation of the differential expression of iNOS in rat primary astrocytes and macrophages. Compounds (calyculin A, microcystin, okadaic acid, and cantharidin) that inhibit PP 1 and 2A were found to stimulate the lipopolysaccharide (LPS)- and cytokine-mediated expression of iNOS and production of NO in rat primary astrocytes and C6 glial cells. However, these inhibitors inhibited the LPS- and cytokine-mediated expression of iNOS and production of NO in rat resident macrophages and RAW 264.7 cells. Similarly, okadaic acid, an inhibitor of PP 1/2A, stimulated the iNOS promoter-derived chloramphenicol acetyltransferase activity in astrocytes and inhibited the iNOS promoter-derived chloramphenicol acetyltransferase activity in macrophages, indicating that okadaic acid also differentially regulates the transcription of the iNOS gene in astrocytes and macrophages. The observed stimulation of the expression of iNOS in astrocytes and the inhibition of the expression of iNOS in macrophages with the inhibition of PP 1/2A activity clearly delineate a novel role of PP 1/2A in the differential regulation of iNOS in rat astrocytes and macrophages. Because the activation of NF-κB is necessary for the induction of iNOS and the expression of tumor necrosis factor (TNF)-α also depends on the activation of NF-κB, we examined the effect of okadaic acid on the LPS-mediated activation of NF-κB and production of TNF-α in rat primary astrocytes and macrophages. Interestingly, in both cell types, okadaic acid stimulated the LPS-mediated DNA binding as well as transcriptional activity of NF-κB and production of TNF-α. This study suggests that the stimulation of iNOS expression in astrocytes by inhibitors of PP 1/2A is possibly due to the stimulation of NF-κB activation; however, activation of NF-κB is not sufficient for the induction of iNOS in macrophages and that apart from NF-κB some other signaling pathway(s) sensitive to PP 1 and/or PP 2A is/are possibly involved in the regulation of iNOS in macrophages. This differential induction of iNOS as compared with similar activation of NF-κB by inhibitors of PP 1/2A indicates the involvement of different intracellular signaling events for the induction of iNOS in two cell types of the same animal species.
The fabrication of vanadium base alloys as candidate fusion reactor materials

Abstract An alloy fabrication program has been initiated at Argonne National Laboratory to provide suitable materials for the evaluation of vanadium base alloys in the United States Fusion Power Program. The initial phase of the work has focused on the VCrTi ternary system. Emphasis has been placed on minimizing impurity levels in the alloy feedstock constituents and on controlling these levels during subsequent processing operations. The effort includes evaluation of the effects of processing variables on the properties of the alloys. Consideration is given to processing techniques that are applicable to larger scale production. Fabrication of 6.8 kg of V15Cr5Ti alloy was carried out by dc arc casting of a number of 350-g ingots. This material was processed by consumable arc melting to yield a 5.9-cm-diameter ingot of the alloy. Further consumable arc melting produced a 9.7-cm-diameter ingot that was used at the start of hot working. This cast ingot was extruded at 1125°C, with stainless steel cladding, to give a 6.6 cm × 3.3 cm × 114.3 cm bar. By scaling down this operation, a 3.5 kg heat of V10Cr5Ti alloy was processed from a cast ingot that was 5.9 cm in diameter. Material from both alloys has been processed further by hot and cold rolling.
Distribution of nerve growth factor-like immunoreactive neurons in the adult rat brain following colchicine treatment

Using immunohistochemical techniques, we have previously localized nerve growth factor (NGF)-like immunoreactivity in the normal adult rat centralnervous system (CNS) exclusively in the hippocampal mossy fiber region andwithin basal forebrain cholinergic neurons—a cell population believed to be primary NGF consumers within the CNS. In the present investigation, we have attempted to identify potential producers of NGF by pretreating animals with colchicine. Such a treatment would be expected to block microtubule-assisted neuritic transport mechanisms, thus preventing the accumulation of antigens normally obtained by retrograde transport and forcingthe accumulation of cell products normally exported anterogradely. Forty-eight hours after colchicine administration within their innervation territories, basal forebrain cholinergic neurons showed a marked loss of NGF-like immunoreactivity. Conversely, following colchicine treatment, many new populations of NGF-like immunoreactive cells were detected, several of which have been previously observed with in situ hybridization techniques for NGF mRNA. Many NGF-like immunoreactive populations, however, were not previously recognized by in situ hybridization methods, including cells of the striatum, reticular thalamic nucleus, paraventricular hypothalamic nucleus, supraoptic nucleus, lateral and medial septum, substantia innominata, and nucleus basalis. Furthermore, evidence is provided that colchicine-blocked, NGF-like immunoreactive neurons within the basal forebrain are not cholinergic, thus reinforcing the hypothesis that trophic support for these NGF-dependent neurons may be derived from distant and local sources. The distinctive distribution of NGF-like immunoreactive cells observed in this study strongly correlates with the reported distribution of NGF mRNA in CNS neurons, thus suggesting that our antibodies are uniquely recognizing NGF and not other related neurotrophins. © 1992 Wiley-Liss, Inc.
Finite element method evaluation: articulations and diagonals in an 8-pin type 1B external skeletal fixator.

Objective— To determine the mechanical properties of articulations and diagonals in an 8-pin type 1b external skeletal fixator (ESF). Study Design— Finite element method—computer simulation. Methods— The control type 1b ESF was supplemented with different articulations and diagonals. The parameters of frame angle, articulation diameter, and pin- or connector-based fastening were altered. The configurations were loaded for axial compression, torsion, and craniocaudal and mediolateral bending as single loads and as a combination. Three-dimensional linear and rotational gap strain and Von Mises stress maxima were determined. Results— For 90°, 60°, and 30° frame angles and 0.48-cm-diameter articulations and diagonals, the best configurations, based on lower gap strain combined with decreased or minimally increased stress maxima for the combined load, were single or double diagonals or four horizontal articulations. Combining double diagonals with double wide horizontal articulations further lowered gap strain. For a 90° frame angle and 0.32-cm-diameter articulations and diagonals, the superior configurations, showing the lowest gap strain combined with decreased or minimally increased stress maxima for the combined load, were double diagonals, four horizontal, or wide double horizontal articulations. The 0.48-cm articulations and diagonals provided lower or similar gap strain than 0.32-cm articulations and diagonals. The connector-to-connector version of these superior configurations provided slightly lower or similar gap strain and stress maxima than the pin-to-pin version. Only pin-to-pin–fastened double diagonals provided better stress maxima than the corresponding connector-to-connector version. Conclusions— Supplementing a type 1b ESF with double diagonals and wide double articulations results in the greatest increase in stability at the fracture gap for complex fractures or in the initial phase of bone healing.
Hybrid Finite Element—Boundary Element Simulation of Rotating Machinery Supported on Flexible Foundation and Soil

Relative and absolute shaft vibration data have revealed that the commonly made assumption of rigidly supported bearings may be grossly inaccurate, especially for fans, generator sets, and natural gas transmission compressors. This paper provides a systematic method for modeling flexibly mounted rotating machinery utilizing 8 node isoparametric brick-type finite elements for the foundation and 4 node isoparametric “patch” type boundary elements for the soil. The rotor is modeled utilizing Euler-Bernoulli beam elements and includes disk gyroscopics and cross coupled bearing coefficients. The large number of degrees of freedom included in the model are reduced utilizing a nested superelement scheme and Guyan reduction.
Rapid interaction of prolactin with mouse mammary gland explants.

Abstract Exposure of mouse mammary gland expiants to prolactin at 0°C, for periods as brief as 10 seconds, caused a stimulation of labeled uridine incorporation into RNA during a subsequent incubation for 4 h at 37°C. Furthermore, a 2-h wash of the prolactin-exposed explants in media at 0°C did not attenuate the hormonal effect. A similar exposure of explants to insulin, followed by a 2-h wash at 0°C, caused the abolition of the insulin stimulation of labeled uridine incorporation into RNA. These results suggest that there is a rapid and relatively stable interaction of prolactin with the mammary gland, while the interaction of insulin with this tissue would appear to be less stable.
Discrete Propagation of Surface Fronts in a Convective Environment: Observations and Theory

Abstract A case example demonstrating that surface fronts can propagate in a discrete manner is presented. The event occurred as a cold front encountered a mesoscale area of surface-based convectively generated cold air over the central United States. The surface front stalled when it reached the cold anomaly and underwent rapid frontolysis. At the same time, a prefrontal trough formed on the downstream boundary of the convective cold dome, about 300 km ahead of the original front, and underwent rapid intensification. Eventually, the original surface front became impossible to identify while the new boundary became the new surface front. A careful inspection of surface reports shows that a front did not pass through the area between the original surface front and the new surface front. However, analysis of rawinsonde and profiler data reveals that the midlevel frontal trough propagated continously. Thus, as the midlevel front moved continously over the cold dome, the surface frontal properties (e.g., pres...
Inelastic collisions in narrow planetary rings

Abstract It is shown that a particle ring with energy dissipation has an extremum in its energy when all the particles are in the same circular orbit. This extremum is a relative maximum in radial directions, indicating possible radial expansion; but it is a relative minimum in the particle velocity components, indicating a tendency for the velocity distribution to collapse. An N-body model of ring evolution incorporating two-body dynamics, oblateness perturbations, inelastic collisions, and phase averaging is described. By local analysis of impact statistics, it is shown that the velocity distribution of the ring will collapse if the coefficient of restitution ∈ ≲ 0.7. The collapse of the velocity distribution stabilizes a ring of point particles against radial dispersion. Furthermore, for ∈ ≲ 0.25, the semimajor axis distribution tends to collapse toward its local mean value, leading to radial collapse. A survey of ring evolution is presented for different values of coefficient of restitution and initial velocity dispersion. As has been predicted uy Goldreich and Tremaine, rings with equilibrium velocity distributions are unstable and expand, while rings where the velocity distribution collapses are shown to undergo massive, pervasive fragmentation into a myriad of ringlets. It is proposed that such fragmented rings are stable in their own right, and that the observational test to discriminate between the two cases is simply the presence of a smooth, featureless surface or the presence of intricate radial structure in the ring.
The nuclear import of protein kinase D3 requires its catalytic activity.

Abstract The protein kinase D (PKD) family consists of three serine/threonine protein kinases termed PKD, PKD2, and PKD3, which are similar in overall structure and primary amino acid sequence. However, each isozyme displays a distinctive intracellular localization. Taking advantage of the structural homology and opposite nuclear localization of PKD2 and PKD3, we generated an extensive set of chimeric proteins between both isozymes to determine which PKD3 domain(s) mediates its nuclear localization. We found that the C-terminal region of PKD3, which contains its catalytic domain, is necessary but not sufficient for its nuclear localization. Real time imaging of a photoactivatable green fluorescent protein fused to PKD3 revealed that point mutations that render PKD3 catalytically inactive completely prevented its nuclear import despite its interaction with importin α and β. We also found that activation loop phosphorylation of PKD3 did not require its nuclear localization, and it was not sufficient to promote the nuclear import of PKD3. These results identify a novel function for the kinase activity of PKD3 in promoting its nuclear entry and suggest that the catalytic activity of PKD3 may regulate its nuclear import through autophosphorylation and/or interaction with another protein(s).
Radiological and Clinical Factors Predicting the Facial Nerve Outcome following Retrosigmoid Approach for Large Vestibular Schwannomas (VSs)

Objective The aim of our study was to identify the radiological and clinical factors that predict postoperative facial nerve outcome following retrosigmoid approach for large vestibular schwannomas (VSs). Methods A total of 72 patients with large (≥ 3 cm) vestibular schwannomas was included in this retrospective study. Various parameters evaluated were age, gender, clinical presentation, tumor diameter in three planes, intrameatal extension, and pattern of growth. Results Age of the patient and presenting symptoms such as headache, ataxia, or preoperative facial nerve dysfunction correlated with poorer facial nerve outcome (p 0.05). Of the various examined factors, preoperative facial nerve function independently predicted postoperative facial nerve outcome. Conclusion Our study suggests that young patients with small tumor volume and normal facial nerve function at presentation are more likely to experience a good postoperative facial nerve outcome. These clinical and radiological parameters can be used to predict facial nerve outcome prior to surgery.
A special holder allows replacement of the recording barrel of a ‘piggy-back’ multibarrel microelectrode

A new form of multibarrel micropipette is described. The special holder has several advantages: it can be quickly replaced if it is damaged; the multi-barrel injection portion of the pipette and the drugs it contains can be reused; contamination by spill-over of drugs from one barrel to another is prevented and pressure techniques can be applied using this micro-electrode.
THIRD MOLAR AGENESIS AND VARIATION IN SIZE OF THE REMAINING TEETH.

SINCE third molar agenesis is clearly associated with an increased incidence of other missing teeth1,2 and with reduction in size of the remaining teeth3, one might also expect increased variation in size, even to the point of hypoplastic or peg teeth, when third molars are missing4.
ENDOCRINE THERAPY OF FUNCTIONAL MENO-METRORRHAGIA AND OVARIAN STERILITY I. THE CYCLIC ADMINISTRATION BY INJECTION OF ESTROGENS AND PROGESTERONE1

THE MARITAL PLANS and maternal aspirations of younger women require the employment of all the conservative therapeutic approaches of a rational therapy when one desires to circumvent the ovarian failure responsible for irregularities of flowing and lowered fertility. The control of uterine hemorrhage by various empiric methods of hemostasis, however, may constitute at times expediential and quite appropriate therapy.
Supporting Algebraic Reasoning through Personalized Story Scenarios: How Situational Understanding Mediates Performance

Context personalization refers to matching instruction to students' out-of-school interests and experiences. Belief in the benefits of matching instruction to interests is widely held in the culture of schooling; however, little research has empirically examined how interest impacts performance and learning in secondary mathematics. Here we investigate these issues with a series of problem-solving sessions where 24 Algebra I students were presented with story problems on linear functions, some of which were personalized to their interests. Our analyses focus on performance, strategy use, and mistake patterns. Results suggest that personalization supported situational reasoning (Nathan, Kintsch, & Young, 1992) about the actions and relationships in the scenario, improving performance for weaker students and on harder problems. However, personalized scenarios seemed to act as a distraction when stronger students in the sample worked on easier problems. Thus context personalization may have the potential to ...
Asymmetrically inherited multidrug resistance transporters are recessive determinants in cellular replicative ageing.

During yeast cell division, multidrug resistance (MDR) transporters partition unequally, with the older pool remaining in the mother cell. Mutations in MDR transporter genes reduce replicative lifespan, whereas an extra copy of these genes extends it, suggesting that defective MDR proteins may influence replicative ageing. Cellular ageing is known to correlate with the accumulation of many harmful agents1, but it is unclear whether ageing can also result from the deterioration of components that are beneficial to the cell, but have a low rate of renewal. Here, we report a group of plasma membrane-associated transporters in yeast, belonging to the multidrug resistance (MDR) protein families, that may represent the latter type of ageing determinants. During the division of a yeast cell, newly synthesized transporter proteins are deposited mostly into the growing bud, whereas previously synthesized MDR proteins remain tightly associated with the mother cortex. Thus, the new and old pools of membrane-bound MDR proteins are spatially segregated during yeast asymmetric cell division, with the older pool stably inherited by the ageing mother. A model based on the observed dynamics of MDR protein inheritance and turnover predicted a decline in MDR activity as the mother cell advances in replicative age. As MDR proteins have crucial roles in cellular metabolism, detoxification and stress response, their collective decline may lead to fitness loss at an advanced age. Supporting this hypothesis, mutants lacking certain MDR genes exhibited a reduced replicative lifespan (RLS), whereas introduction of only one extra copy of these MDR genes extended RLS.
Adrenergic receptor polymorphisms associated with resting heart rate: The HyperGEN study

The association between polymorphisms in the beta1, beta2 and alpha2B adrenergic receptor (ADR) genes (ADRB1, ADRB2 and ADRA2B) and resting heart rate was examined in white and African-American participants of the HyperGEN Study. All analyses were adjusted for age, sex, body mass index, alcohol use, smoking status and daily exercise within strata of race, hypertension status and beta-blocker use. The Ser49Gly polymorphism of the beta1 ADR was associated with resting heart rate in hypertensive African-Americans and hypertensive whites taking beta-blockers, with carriers of the Gly allele having a higher mean resting heart rate by 2.7 and 4.4 beats per minute (bpm), respectively. The Arg389Gly polymorphism of the beta1 ADR was associated with lower heart rate in the normotensive African-American sample. A beta1 haplotype (Ser49Gly-Arg389Gly) was modestly associated with resting heart rate in the hypertensive African-Americans. The alpha2B C/A polymorphism was associated with heart rate in hypertensive whites, and both whites and African-Americans taking beta-blockers, with carriers of the A allele having a higher mean resting heart rate. In summary, each of the ADR gene polymorphisms was associated with heart rate in at least one stratum studied, but there was no consistent association from which one would infer a large genetic contribution to heart rate.
Modeling cellular signaling: taking space into the computation

In living systems, chemical reactions and the geometry of cells feed back on each other. Methods for computational modeling are beginning to take this complexity into account.
Network signatures of nuclear and cytoplasmic density alterations in a model of pre and postmetastatic colorectal cancer

Cells contributing to the pathogenesis of cancer possess cytoplasmic and nuclear structural alterations that accompany their aberrant genetic, epigenetic, and molecular perturbations. Although it is known that architectural changes in primary and metastatic tumor cells can be quantified through variations in cellular density at the nanometer and micrometer spatial scales, the interdependent relationships among nuclear and cytoplasmic density as a function of tumorigenic potential has not been thoroughly investigated. We present a combined optical approach utilizing quantitative phase microscopy and partial wave spectroscopic microscopy to perform parallel structural characterizations of cellular architecture. Using the isogenic SW480 and SW620 cell lines as a model of pre and postmetastatic transition in colorectal cancer, we demonstrate that nuclear and cytoplasmic nanoscale disorder, micron-scale dry mass content, mean dry mass density, and shape metrics of the dry mass density histogram are uniquely correlated within and across different cellular compartments for a given cell type. The correlations of these physical parameters can be interpreted as networks whose nodal importance and level of connection independence differ according to disease stage. This work demonstrates how optically derived biophysical parameters are linked within and across different cellular compartments during the architectural orchestration of the metastatic phenotype.
The effect of uni-axial stretching on the roughness of microfiltration membranes

Abstract Atomic force microscopy (AFM) was used to characterize the surface morphology of uni-axially stretched and non-stretched microporous microfiltration (MF) membranes. The effect of stretching on the pore structure and bulk properties of MF membranes has been previously reported [J.A. Morehouse, L.S. Worrel, D.L. Taylor, D.R. Lloyd, B.D. Freeman, D.F. Lawler, The effect of uni-axial orientation on macroporous membrane structure, J. Porous Mater. 13 (2006) 63–75.]; this paper focuses solely on the use of AFM to characterize the surface of stretched and non-stretched MF membranes. A new way of representing surface roughness that may prove useful in relating roughness to performance in cross-flow applications is presented.
Retinol binding protein is produced by the bovine endometrium and accumulates in uterine secretions in a progesterone-dependent manner

Abstract Studies were conducted to establish whether (a) uterine lumenal fluids contain an immunoreactive retinol binding protein (RBP), (b) such a protein is produced by the uterine endometrium, (c) retinol binding activity can be associated with immunoreactive RBP, and (d) presence of the immunoreactive RBP is regulated by progesterone. When using antiserum to human RBP (serum form) as a probe in immunoblotting, three molecular weight classes of protein species could be detected in uterine lavage fluids of pregnant and bred/nonpregnant cows at Day 17 after estrus and in culture supernatants of cyclic, bred/nonpregnant and pregnant cows at Day 17 after estrus. The predominant band was at a molecular weight (Mr) of 22 000 (RBP 22) but several other minor bands could be detected at molecular weights of 25 000–30 000 (RBP 25–30) and 55 000–65 000 (RBP 55–65). These immunoreactive forms of RBP could be detected in serum. Addition of cycloheximide to endometrial cultures inhibited amounts of RBP 22 in supernatants of endometrial cultures, confirming in vitro synthesis of RBP by endometrium. Biological activity was confirmed by incubation of immunoblots with 3 H-retinol: specific binding of radiolabel was associated with RBP 22 and RBP 55–65. To investigate regulation of secretion of RBP, ovariectomized cows were treated with corn oil vehicle for 12 days or with 750 mg day −1 progesterone for 12 or 30 days. While immunoblots revealed RBP 22 in uterine lavage fluids of endometrial explants from all cows, progesterone-treated cows had more RBP 22 in uterine lavage fluids than did cows treated with vehicle alone. Staining intensities of RBP 25–35 and RBP 55–65 were not affected by treatment. It was concluded that the uterine lumen contains a retinol binding protein that is derived from both local endometrial synthesis and blood. Furthermore, amounts of RBP in uterine secretions are regulated by progesterone.
SATURATED THICKNESS OF NITRIDE LAYERS FORMED BY HIGH FLUENCE NITROGEN IMPLANTATION INTO METALS

Abstract The thickness of the nitride layer formed by a high fluence nitrogen implantation to a metal surface is limited mainly because of the sputtering effects and the migration of the implanted nitrogen towards the surface. We have investigated nitrogen depth profiles implanted to several kinds of metals theoretically by Monte Carlo simulation using the dynamic-SASAMAL code and experimentally by RBS and NRA using the 15 N(p,????) 12 C reaction. In this paper, the saturation fluence and the saturated nitride thickness were calculated for 1???200 keV nitrogen implantations into several kinds of metals (Al, Ti, Fe, Zr, and Hf). In order to find the method to overcome the limited thickness and the severe radiation damage problem at the high fluence implantations necessary for the saturation, the nitrogen depth profiles for an energy scanning implantation with a uniform and a non-uniform energy distribution was calculated and compared with those of mono-energetic implantations.
Protein synthesis in rabbit reticulocytes: Mg2+ - inhibition of ternary complex (met-tRNAf·eIF-2·GTP) formation by reticulocyte eIF-2

Abstract There are conflicting reports regarding Mg2+-inhibition of ternary complex formation by reticulocyte eIF-2. Several laboratories have reported that eIF-2 is isolated as eIF-2·GDP and Mg2+ inhibits ternary complex formation, as in the presence of Mg2+, GDP remains tightly bound to eIF-2 and prevents ternary complex formation. A protein factor, GEF is necessary for GDP displacement and subsequent ternary complex formation. Other laboratories have reported that Mg2+ has no effect on eIF-2 activity and eIF-2 forms near stoichiometric amount of ternary complex in the presence of Mg2+. In this paper, we provide evidence which suggests that the Mg2+-insensitive eIF-2 activity as reported by several laboratories might have been the result of the use of high Met-tRNAf concentrations in their assays as the nucleotides in excess tRNA bound Mg2+ in the reaction mixture and there was no free Mg2+ available to inhibit eIF-2 activity. Our data will show that the addition of excess tRNA promotes non-enzymatic GDP displacement from eIF-2·GDP and relieves Mg2+ inhibition.
The relationship between lymphogenous and hematogenous metastasis in rats bearing the MT-100-TC mammary carcinoma.

Temporal and quantitative aspects of lymphogenous and hematogenous metastasis were examined using the rat MT-100-TC mammary carcinoma injected into the hind feet of syngeneic rats. Metastases first appeared in the draining popliteal nodes and then progressed in an invariable pattern to regional and then distal nodes: ‘skipped’ negative nodes within a chain of positive nodes were not observed. Metastatic progression in the lymphatic system occurred metachronously, with nodal metastases acting as ‘generalizing’ sites for ‘downstream’ nodes. Perturbation of lymph flow was apparent when nodes were involved with tumor, and resulted in retrograde seeding of contralateral nodes. Lung involvement was first observed by ectopic bioassay in 50 per cent of animals after 1 and 2 weeks of primary tumor growth; in contrast, all animals had popliteal involvement after 1 week. These results indicate that lymph nodes and lungs are not seeded synchronously, and the lungs are seeded after nodal metastases. Thus, a phase of metastasis has been identified, during which resection of the primary tumor and local nodes may well be curative in the 50 per cent of cases in which the disease is confined to these sites.
Lafayette College's Network Project Description

In the fall of 1988, the vision of Lafayette College President David Ellis began to be realized when the Board of Trustees committed to create a leading‐edge campus‐wide computer environment that would provide unlimited twenty‐four‐hour access for every member of the Lafayette community to state‐of‐the‐art information systems technology.
Rural Transit Services: A Local Economic and Fiscal Impact Analysis

Rural transit services are generally considered a tool to alleviate immobility for the elderly, the handicapped, and the carless and a form of income redistribution to them from society at large. But their economic impacts on local economies and governments are seldom realized and quantified. This study estimates two important transfer impacts of rural transit service on local (county) economies and governments in Georgia: the overall economic impacts and the fiscal revenue impacts. This study analyzed economic benefits of three major transit rider types in rural Georgia: elderly riders, work trip riders, and school trip riders. It found that rural transit services have a significant and positive economic impact on the local economy, indicating that, in addition to providing mobility and accessibility to the transportation disadvantaged, rural transit services promote local economic development. The fiscal revenue impact of rural transit service varies depending on the availability and the amount of feder...
Newer developments in adult T-cell leukemia/lymphoma therapeutics

Introduction: Adult T-cell leukemia/lymphoma (ATL) is a rare disease with a unique geographic distribution. Conducting controlled randomized trials to assess the effective therapeutic strategies has therefore been a significant challenge to date. Areas covered: This review explores the natural history and diagnostic evaluation of ATL, followed by a focused review of existing studies on the most potent individual pharmaceutical agents and combinations used in the therapy of this malignancy. Readers will acquire considerable insights about the clinical subsets, diagnosis and the most effective therapies used in various ATL types. Expert opinion: International, multicenter, randomized clinical trials are essential to design optimal therapeutic strategies for various ATL subsets. It appears that patients with acute ATL type benefit considerably from the first-line combined antiviral therapy with zidovudine and interferon alpha, whereas patients with ATL of the lymphoma type may experience a better outcome wit...
SETTLE: an analytical version of the SHAKE and RATTLE algorithm for rigid water models

An analytical algorithm, called SETTLE, for resetting the positions and velocities to satisfy the holonomic constraints on the rigid water model is presented. This method is still based on the Cartesian coordinate system and can be used in place of SHAKE and RATTLE. We implemented this algorithm in the SPASMS package of molecular mechanics and dynamics. Several series of molecular dynamics simulations were carried out to examine the performance of the new algorithm in comparison with the original RATTLE method. It was found that SETTLE is of higher accuracy and is faster than RATTLE with reasonable tolerances by three to nine times on a scalar machine. Furthermore, the performance improvement ranged from factors of 26 to 98 on a vector machine since the method presented is not iterative. © 1992 by John Wiley & Sons, Inc.
Pollen performance before and during the autotrophic–heterotrophic transition of pollen tube growth

For species with bicellular pollen, the attrition of pollen tubes is often greatest where the style narrows at the transition between stigmatic tissue and the transmitting tissue of the style. In this region, the tubes switch from predominantly autotrophic to predominantly heterotrophic growth, the generative cell divides, the first callose plugs are produced, and, in species with RNase-type self-incompatibility (SI), incompatible tubes are arrested. We review the literature and present new findings concerning the genetic, environmental and stylar influences on the performance of pollen before and during the autotrophic-heterotrophic transition of pollen tube growth. We found that the ability of the paternal sporophyte to provision its pollen during development significantly influences pollen performance during the autotrophic growth phase. Consequently, under conditions of pollen competition, pollen selection during the autotrophic phase is acting on the phenotype of the paternal sporophyte. In a field experiment, using Cucurbita pepo, we found broad-sense heritable variation for herbivore-pathogen resistance, and that the most resistant families produced larger and better performing pollen when the paternal sporophytes were not protected by insecticides, indicating that selection during the autotrophic phase can act on traits that are not expressed by the microgametophyte. In a study of a weedy SI species, Solanum carolinense, we found that the ability of the styles to arrest self-pollen tubes at the autotrophic-heterotrophic transition changes with floral age and the presence of developing fruits. These findings have important implications for selection at the level of the microgametophyte and the evolution of mating systems of plants.
The economic impact of public beta testing: the power of word-of-mouth

The advent of the Internet has brought many fundamental changes to the way business is conducted. Among others, a growing number of software firms are relying on public beta testing to improve the quality of their products before release. While the benefits resulting from improved software reliability have been widely recognized, the influences of public beta testers on the diffusion of a new software product have not been documented. Through their word&of&mouth effect , public beta testers can speed up the diffusion of a software product after release, and hence increase the time&discounted revenue per adopter. In this research, we take into consideration both the reliability& side and the diffusion&side of the benefits, and de velop methodologies to help firms decide the optimal number of public beta testers and the optimal duration of public beta testing. Numerical results show the firm’s profit can increase substantially by taking advantage of the world&of&mouth of public beta test ers. This benefit is more significant if firms recruit beta testers from those who can benefit from a software product but cannot afford it.
A layer-recursive formula for the medium filter for volume conductor problems in radially symmetric layered media (bioelectricity application)

Simplified algorithms for the computation of the filter coefficients used in solutions of the forward and inverse volume conductor problems in a multilayered cylindrical geometry are derived. The new algorithms are layer-recursive, as opposed to previous algorithms which were specific for the structure studied. The new algorithms not only eliminate the need to derive algebraically cumbersome filter expression, but also speed up their numerical evaluation. >
Reduced Ornithine Transcarbamylase Activity Does Not Impair Ureagenesis in Otcspf-ash Mice

Mouse models for urea cycle disorders have been available for the past 30 y; however, until now, no measurements of urea production in vivo have been conducted. Urea entry rate was determined in Otc spf-ash and littermate controls employing a primed-continuous infusion of 15 N 15 N urea. A saline infusion control, a complete mixture of amino acids (AA), or a glycine-alanine (GA) mixture was infused at 86 (AA1 and GA1) and 172 mg Nkg � 1 � h � 1 (AA2 and GA2) to impose a defined nitrogen load on the urea cycle. Urea entry rate and plasma urea concentration increased (P , 0.001) as a consequence of the increase in the infusion rate of the complete mixture of amino acids, but the 2 genotypes did not differ (P ¼ 0.96 and P ¼ 0.44, respectively). The infusion of the GA mixture, however, decreased (P , 0.001) the plasma urea concentration and urea entry rate in Otc spf-ash mice compared with controls. At the highest level (GA2), urea entry rate was further depressed (P , 0.001), Otc spf-ash mice became hyperammonemic (1701 6 150 mmol/L), and hyperammonemic symptoms were evident. An acute hepatic enlargement (P , 0.001) was also evident in Otc spf-ash mice infused with GA2. These results show that despite vestigial OTC activity, Otc spf-ash mice were able to maintain ureagenesis at the same rate of control animals when a complete mixture of amino acids was infused. This implies that Otc spf-ash mice are able to dispose of ammonia, without apparent adverse effects, when a balance mixture of amino acids is provided, despite reduced enzyme activity. J. Nutr. 136: 1017-1020, 2006.
Effects of Pseudomonas aeruginosa endotoxin on vasodilation in the intact spinotrapezius muscle.

The purpose of this study was to determine whether short-term exposure to clinically relevant concentrations of Pseudomonas aeruginosa lipopolysaccharide (LPS) impairs vasoreactivity of resistance ...