cssi/SciSciGPT-SciSciNet huggingface dataset:
Performance guarantees for Web server end-systems: a control-theoretical approach

The Internet is undergoing substantial changes from a communication and browsing infrastructure to a medium for conducting business and marketing a myriad of services. The World Wide Web provides a uniform and widely-accepted application interface used by these services to reach multitudes of clients. These changes place the Web server at the center of a gradually emerging e-service infrastructure with increasing requirements for service quality and reliability guarantees in an unpredictable and highly-dynamic environment. This paper describes performance control of a Web server using classical feedback control theory. We use feedback control theory to achieve overload protection, performance guarantees, and service differentiation in the presence of load unpredictability. We show that feedback control theory offers a promising analytic foundation for providing service differentiation and performance guarantees. We demonstrate how a general Web server may be modeled for purposes of performance control, present the equivalents of sensors and actuators, formulate a simple feedback loop, describe how it can leverage on real-time scheduling and feedback-control theories to achieve per-class response-time and throughput guarantees, and evaluate the efficacy of the scheme on an experimental testbed using the most popular Web server, Apache. Experimental results indicate that control-theoretic techniques offer a sound way of achieving desired performance in performance-critical Internet applications. Our QoS (Quality-of-Service) management solutions can be implemented either in middleware that is transparent to the server, or as a library called by server code.
A 35-kDa protein is the basic unit of the core from the 2 x 10(4)-kDa aggregation factor responsible for species-specific cell adhesion in the marine sponge Microciona prolifera.

Dissociated sponge cells quickly reaggregate in a species-specific manner, differentiate, and reconstruct tissue, providing a very handy system to investigate the molecular basis of more complex intercellular recognition processes. Species-specific cell adhesion in the marine sponge Microciona prolifera is mediated by a supramolecular complex with a Mr = 2 × 107, termed aggregation factor. Guanidinium hydrochloride/cesium chloride dissociative gradients and rhodamine B isothiocyanate staining indicated the presence of several proteins with different degrees of glycosylation. Hyaluronate has been found to be associated with the aggregation factor. Chemical deglycosylation revealed a main component accounting for nearly 90% of the total protein. The cDNA-deduced amino acid sequence predicts a 35-kDa protein (MAFp3), the first sponge aggregation factor core protein ever described. The open reading frame is uninterrupted upstream from the amino terminus of the mature protein, and the deduced amino acid sequence for this region has been found to contain a long stretch sharing homology with the Na+-Ca2+ exchanger protein. A putative hyaluronic acid binding domain and several putative N- and O-glycosylation signals are present in MAFp3, as well as eight cysteines, some of them involved in intermolecular disulfide bridges. Northern blot data suggest variable expression, and Southern blot analysis reveals the presence of other related gene sequences. According to the respective molecular masses, one aggregation factor molecule would contain about 300 MAFp3 units, suggesting that sponge cell adhesion might be based on the assembly of multiple small glycosylated protein subunits.
Multiscale finite element methods for high-contrast problems using local spectral basis functions

In this paper we study multiscale finite element methods (MsFEMs) using spectral multiscale basis functions that are designed for high-contrast problems. Multiscale basis functions are constructed using eigenvectors of a carefully selected local spectral problem. This local spectral problem strongly depends on the choice of initial partition of unity functions. The resulting space enriches the initial multiscale space using eigenvectors of local spectral problem. The eigenvectors corresponding to small, asymptotically vanishing, eigenvalues detect important features of the solutions that are not captured by initial multiscale basis functions. Multiscale basis functions are constructed such that they span these eigenfunctions that correspond to small, asymptotically vanishing, eigenvalues. We present a convergence study that shows that the convergence rate (in energy norm) is proportional to (H/??)1/2, where ?? is proportional to the minimum of the eigenvalues that the corresponding eigenvectors are not included in the coarse space. Thus, we would like to reach to a larger eigenvalue with a smaller coarse space. This is accomplished with a careful choice of initial multiscale basis functions and the setup of the eigenvalue problems. Numerical results are presented to back-up our theoretical results and to show higher accuracy of MsFEMs with spectral multiscale basis functions. We also present a hierarchical construction of the eigenvectors that provides CPU savings.
Prostatic involvement by transitional cell carcinoma in patients with bladder cancer and its prognostic significance

To study the importance of prostatic involvement by transitional cell carcinoma (TCC) in patients with bladder cancer, we examined the entire prostates by whole-mount sections from 214 radical cystoprostatectomy specimens for detailed patterns of involvement by TCC and correlated the results with lymph node metastasis and patients' survival. Prostatic involvement by TCC was detected in 69 (32%) of 214 cases. Among them, 30 (43%) patients had carcinoma in situ (CIS) and the other 39 (57%) were invasive TCC. Carcinoma in situ occurred in either prostatic urethra (n = 6, 20%) or, more commonly, in prostatic ducts/acini (n = 14, 47%), and in a combination of prostatic urethra and ducts (n = 10, 33%). Ten (26%) of the invasive TCC resulted from direct penetration from the primary tumor in the bladder, and the remaining 29 (72%) cases arose from prostatic urethra/ducts, of which 11, 13, and 5 invaded the lamina propria, prostatic stroma, and periprostatic or seminal vesical tissue, respectively. Both prostatic TCC involvement and nodal metastasis were highly significant prognostic factors for patients' survival and the survival significance of prostatic TCC involvement still existed regardless of lymph node status. Furthermore, the presence of prostatic CIS and degrees of prostatic invasion are associated with nodal metastasis and survival. Patients with prostatic CIS or urethral lamina propria invasion had a similar, but higher incidence of lymph node metastasis and lower long-term and 5-year survival than those patients without prostatic involvement. Similarly, prostatic stromal invasion and periprostatic/seminal vesical invasion had a similar, but much higher nodal metastasis and worse survival than patients with only prostatic CIS or urethral lamina propria invasion. In summary, presence of prostatic TCC involvement and levels of involvement are significant prognostic factors in patients with bladder cancer.
Competition over Time-Inconsistent Consumers

How do firms respond to consumers' time inconsistency? This paper studies the optimal design of nonexclusive contracts under competition. It shows that nonexclusivity creates a stark asymmetry between immediate-costs goods and immediate-rewards goods. For immediate-cost goods nonexclusivity does not affect the equilibrium and, when consumers are sophisticated, the efficient allocation is achieved. When consumers are partially naive, the optimal sales tax may be either positive or negative and depends on parameters that are hard to estimate. In the case of immediate-rewards goods, however, the equilibrium features marginal-cost pricing and is always inefficient. Moreover, the optimal tax does not depend on the consumers' degree of naivete and is a function of parameters that are easy to assess.
Synthesis and monoamine transporter affinity of 2β-carbomethoxy-3β-(4′- p -substituted phenyl)-piperidine analogs of cocaine

A series of novel piperidine based analogs of cocaine was synthesized and evaluated in vitro against the three monoamine transporters to develop new potential selective SERT radiotracers. Modification of the phenyl substitution with five-membered heterocyclic groups resulted in a wide affinity and selectivity scale. Radiolabeling and mouse in vivo study was performed on the piperidine analog of ZIENT, which crossed the blood-brain barrier but failed to selectively accumulate in the regions of the brain rich in SERT.
A Raman spectrophotometric investigation of the phases formed during the cobalt silicidation by rapid thermal anneal

Raman spectrophotometry was used to determine the various phases of cobalt silicide formed during rapid thermal annealing of cobalt films deposited onto silicon (100) substrates. The samples were prepared by depositing a 600 AR cobalt film and then letting the reaction occur in a nitrogen ambient. Annealing was done for 20 s at temperatures ranging from 200 to 1000°C. The unreacted cobalt film was removed from the surface for the Raman spectrophotometric study. The initial phase, characterized as Co2Si, formed at 250°C. Two subsequent phases, CoSi and CoSi2, were identified as forming at 300 and 500°C, respectively. The corresponding three Raman peaks appeared at 204, 306 and 515.3 Δcm−1, respectively. These peaks appeared and disappeared in accordance with the phase change in the film. The co-existence of the two initial phases, Co2Si and CoSi, at temperatures near 300°C was also evidenced by Raman spectrophtometry. The Raman data correlated well with Auger electron spectroscopic depth profiles.
Reliability of dynamic systems in random environment by extreme value theory

Abstract A practical method is developed for estimating the performance of highly reliable dynamic systems in random environment. The method uses concepts of univariate extreme value theory and a relatively small set of simulated samples of system states. Generalized extreme value distributions are fitted to state observations and used to extrapolate Monte Carlo estimates of reliability and failure probability beyond data. There is no need to postulate functional forms of extreme value distributions since they are selected by the estimation procedure. Our approach can be viewed as an alternative implementation of the method in [7] for estimating system reliability. Numerical examples involving Gaussian and non-Gaussian system states are used to illustrate the implementation of the proposed method and assess its accuracy.
Applying Dutch and US versions of the BSID-II in Dutch children born preterm leads to different outcomes.

The aim of the present study was to evaluate whether the application of Dutch versus US test procedures and norms of the Bayley Scales of Infant Development - 2nd edition (BSID-II) leads to different developmental outcomes. The BSID-II was administered to 376 preterm infants (191 males, 185 females; mean gestational age 30wks [SD 2.7], mean birth-weight 1242g [SD 385]) at corrected ages of 6, 12, 24, and/or 36 months. Raw scores were calculated twice with US and Dutch test procedures. Raw scores as well as Mental Developmental Index (MDI) and Psychomotor Developmental Index (PDI) scores, calculated on the basis of Dutch versus US normative data, were compared. Small but statistically significant Dutch—US differences were found between raw scores. Large, clinically relevant Dutch—US differences were found for MDI and PDI scores, especially at 6 and 12 months. These differences were likely to have been caused by a bias in the Dutch normative data, although a slower developmental pace of Dutch children in general could also have a role. This study highlights the problems that can occur when using a test that was developed in another country, even when local standardization is available.
Vascular events, mortality, and preventive therapy following ischemic stroke in the elderly

Background: The authors studied mortality, vascular events, and preventive therapies following ischemic stroke among adults aged ≥65 years. Methods: The authors identified 546 subjects with first ischemic stroke during 1989 to 2001 among Cardiovascular Health Study participants. Deaths, recurrent strokes, and coronary heart disease (CHD) events were identified over 3.2 years (median) follow-up. Results: During the first year of follow-up, rates were 105.4/1,000 for recurrent stroke and 59.3/1,000 for CHD. After the first year, the stroke rate was 52.0/1,000 and the CHD rate was 46.5/1,000. Cardioembolic strokes had the highest mortality (185.4/1,000) and recurrence rates (86.6/1,000). Lacunar strokes had the lowest mortality (119.3/1,000) and recurrence rates (43.0/1,000). Age and male sex predicted death and CHD, but not recurrence. Outcomes did not differ by race. Following stroke, 47.8% used aspirin and 13.5% used other antiplatelet agents; 52.6% of patients with atrial fibrillation used warfarin; 31.3% of hyperlipidemic subjects, 57.0% of diabetic patients, and 81.5% of hypertensive patients were drug-treated; and 40.0% of hypertensive patients had blood pressure (BP) Conclusions: Recurrent strokes were nearly twice as frequent as coronary heart disease (CHD) events during the first year after initial stroke, but stroke and CHD rates were similar after the first year. Preventive drug therapies were underused, which may reflect clinical uncertainty due to the lack of clinical trials among the elderly. Utilization was lower among the oldest patients, women, and low-income individuals.
Direct contralateral inhibition in the lower sacral spinal cord

Abstract The possibility of an interneuron in the so-called “direct” inhibitory pathway has been examined by studying postsynaptic potentials of motor horn cells in the S2–S3 segments of cat's spinal cord following excitatory and inhibitory volleys in ipsilateral and contralateral dorsal roots. Monosynaptic connections were demonstrated histologically from ipsilateral dorsal roots to motor horn cell somata and dendrites and from contralateral dorsal roots to motor horn cell dendrites alone. However, direct comparison of ipsilateral EPSP and contralateral IPSP latencies in the same unit showed an IPSP latency longer than the EPSP latency by 0.3 to 0.7 msec. Since no adequate explanation could be found to account for this extra latency on the basis of monosynaptic connections, the presence of an interneuron in the direct inhibitory pathway remains a definite possibility.
Epidural Spinal Cord Compression

Epidural spinal cord compression is a neurologic emergency requiring immediate attention. The therapy instituted depends on several factors, including the patient’s condition at the time of presentation, the nature of the underlying malignancy, the extent of systemic disease burden, and patient prognosis. The most essential aspect of treatment is the establishment of the diagnosis. If one suspects malignant cord compression an emergency, magnetic resonance imaging of the entire spinal axis is indicated. If magnetic resonance imaging is unavailable, post-myelographic computed tomography is an alternative. However, treatment should not be delayed until imaging is performed, particularly if neurologic deficits are present. Pain should be adequately addressed and opioids administered if necessary. Steroids should be given. If significant neurologic deficits are present, a high-dose corticosteroid bolus, followed by standing doses, should be given. However, if pain is the predominant symptom, steroids can be withheld pending immediate imaging or lower doses can be given without a bolus. Neurosurgical consultation should be obtained, and surgery should be considered if the patient’s condition permits. This is particularly true if spinal instability or significant kyphosis is present or compression is secondary to bony fragments. Other indications include patients with limited systemic disease burden in whom better survival is predicted and possibly those with radioresistant tumors. The type of surgery performed should be tailored to the distribution of disease within the spine and accessibility through anterior body cavities. Radiation therapy, an effective noninvasive treatment that can be delivered quickly and safely, is an appropriate option as well. This is particularly true in radio-responsive tumors, such as myeloma and lymphoma, in which surgery may be avoided entirely. Chemotherapy may play a role as adjuvant therapy in some tumors.
ACADEMIC SCHOOL PSYCHOLOGISTS: ADDRESSING THE SHORTAGE

A number of factors have impacted on the profession of school psychology during the past 20 to 30 years. These changes have had a profound effect on practice and training issues. Since the 1970s, the demand for school psychologists has increased dramatically. Fagan and Wise (2000) reported that the number of practicing school psychologists increased from 5,000 in 1970 to 25,000 in 2000, and the number of school psychology programs increased from 100 in 1970 to 218 in 2000. In addition, the requirements for credentialing as a school psychologist and the trend toward program accreditation [i.e., approval by the National Association of School Psychologists (NASP), American Psychological Association (APA) accreditation] have increased the demand on programs to provide a comprehensive education in school psychology, including increasing the number of faculty trained as school psychologists. These, and other factors, have led to the current situation in which there is a perceived shortage of appropriately trained individuals entering the school psychology professorate. It is the intent of this article to (a) document the shortage in the school psychology professorate, (b) discuss reasons that may account for this situation and barriers to overcoming the shortage, (c) discuss a survey of school psychology programs in an attempt to identify programs with a consistent track record in preparing students entering the professorate, and (d) discuss factors that may assist doctoral-level programs in achieving outcomes similar to these programs.
Comparison of opiate- and opioid-peptide-induced immobility

Abstract Intraventricular administration of the endogenous opioid peptide β-endorphin produces a profound state of immobilization in rats characterized by the absence of spontaneous movement, loss of the righting response and extreme generalized muscular rigidity. The immobility syndrome induced by the opioid peptides β-endorphin and D-Met 2 -Pro 5 -enkephalinamide was compared with the behavioral profile prodced by subcutaneous and intraventricular administration of the opiates, morphine, methadone and etonitazene. The results indicate a close similarity between the pattern of effects caused by the opiates and opioid peptides. The immobility syndrome could also be produced by injection of β-endorphin into the ventromedial periaqueductal gray, but not into the caudate, globus pallidus, amygdala or dorsolateral periaqueductal gray. The resemblance between the opiate- and β-endorphin-induced profiles suggests that their effects are mediated through common mechanisms.
Pompe disease: Dramatic improvement in gastrointestinal function following enzyme replacement therapy. A report of three later-onset patients

Pompe disease is a lysosomal storage disease due to deficient acid α-glucosidase (GAA) activity. Infants with the classic infantile-onset subtype present with severe hypotonia and cardiomegaly, and most expire in the first year of life, whereas the severity of the muscle-based manifestations in patients with the late infantile/juvenile and adult-onset subtypes depends on the level of GAA residual enzymatic activity. The clinical features of later-onset Pompe disease are still emerging, and even the natural history and progression of muscle weakness and respiratory failure, hallmarks of the later-onset subtypes, are not well documented. For example, we report here three later-onset patients who had chronic diarrhea, postprandial bloating and abdominal pain, previously unrecognized manifestations of later-onset Pompe disease. Two patients had intestinal incontinence and one reported synchronous vomiting and diarrhea on a daily basis. These symptoms significantly interfered with their quality of life, often limiting their ability to leave home. All gastrointestinal symptoms resolved within the first six months of enzyme replacement therapy (ERT) with recombinant human alglucosidase alpha (rhGAA). All three patients gained weight and remain symptom free, two for over four years. Thus, gastrointestinal symptoms occur in later-onset patients with Pompe disease and are resolved with ERT.
Toxicity, survivability, and activity patterns of northern bobwhite quail dosed with the insecticide terbufos

The effects of the organophosphorus insecticide terbufos on laboratory-reared and wild northern bobwhites (Colinus virginianus) were investigated in laboratory dosing studies and dose-release field trials. Laboratory studies yielded a terbufos LD50 of 24.4 mg/kg-body weight (bw). All mortalities occurred within the first 24 h post-dose. Wild bobwhites were trapped, administered 0, 3, 5.6, or 21 mg/kg-bw terbufos by oral intubation, released at their trapping site, and monitored for 14 d. Mortality, activity, and locational data were recorded. Bobwhites treated with 21 mg/kg-bw terbufos had significantly lower survival (p = 0.04) than control birds, while survival at the lower doses was unaffected. No significant differences (p = 0.06) were detected in physical activity among treatments. The 21-mg/kg-bw dose yields an anticipated 37% mortality (or LD37) when interpolated from the LD50 slope equation. After adjustment for control mortality, the 21-mg/kg-bw dose led to 44% mortality in wild bobwhites. This was a 7% higher mortality than predicted by interpolation from the laboratory generated LD50. These results indicate that there was not a substantial increase in mortality of wild bobwhites compared to laboratory-reared bobwhites at nonlethal or lethal, sub-LD50, doses.
Altered perfusion, ventilation, anesthesia and lung-surface forces in dogs.

The combination of hyperventilation, lowered pulmonary blood flow and pentobarbital-O2 anesthesia led to a progressive increase in retractive forces of the lung accompanied by a gradual reduction in inflatable volume in dogs studied for eight hours. After four hours of ventilation, significant changes began to appear at the higher transpulmonary pressures. Results after four hours of ventilation were similar in other dogs treated identically except for the addition of 1.2 per cent halothane to the inspired gas. Hyperventilation and the absence of pulmonary arterial blood flow led to significant (P
Abstract A16: Aberrant signaling pathways in squamous cell lung carcinoma

Lung cancer is the second most commonly occurring non-cutaneous cancer in the United States with the highest mortality rate among both men and women. In this study, we utilized three lung cancer microarray datasets generated by previous researchers to identify differentially expressed genes, altered signaling pathways, and assess the involvement of Hedgehog (Hh) pathway. The three datasets contain the expression levels of tens of thousands genes in normal lung tissues and squamous cell lung carcinoma. The datasets were combined and analyzed. The dysregulated genes and altered signaling pathways were identified using statistical methods. We then performed Fisher9s exact test on the significance of the association of Hh pathway downstream genes and squamous cell lung carcinoma. 395 genes were found commonly differentially expressed in squamous cell lung carcinoma. The genes encoding fibrous structural protein keratins and cell cycle dependent genes encoding cyclin-dependent kinases were significantly up-regulated while the ones encoding LIM domains were down. Over 100 signaling pathways were implicated in squamous cell lung carcinoma, including cell cycle regulation pathway, p53 tumor-suppressor pathway, IL-8 signaling, Wnt-β-catenin pathway, mTOR signaling and EGF signaling. In addition, 37 out of 223 downstream molecules of Hh pathway were altered. The pvalue from the Fisher9s exact test indicates that Hh signaling is implicated in squamous cell lung carcinoma. Numerous genes were altered and multiple pathways were dysfunctional in squamous cell lung carcinoma. Many of the altered genes have been implicated in different types of carcinoma while some are organ-specific. Hh signaling is implicated in squamous cell lung cancer, opening the door for exploring new cancer therapeutic treatment using GLI antagonist GANT 61.
Identification of a missense mutation and several polymorphisms in the proenkephalin A gene of schizophrenic patients

Schizophrenia is a complex and severe disorder of unknown cause and pathophysiology. In this study, we examined the opioid hypothesis for schizophrenia at the molecular level, focusing on the dopamine-regulated proenkephalin A gene (chromosome 8q11.23-q12). We have screened 150 schizophrenic patients for sequence variations within the promoter region, entire coding sequence, and 3'-untranslated region. We find one sequence change in a conserved amino acid that may be of functional significance. This mutation was found in a single schizophrenia patient but not in controls. Although several new, race-specific polymorphisms were identified, all other sequence changes appeared to be common polymorphisms, unlikely to contribute to the etiology of schizophrenia.
YM-09151-2: a potent antagonist for a peripheral D2-dopamine receptor.

Abstract YM-09151-2 (cis-N-(1-benzyl-2-methylpyrrolidin-3-yl)-5-chloro-2-methyoxy-4-methylaminobenazamide) is a potent antagonist of the dopamine-induced inhibition of adenylate cyclase in the cholera toxin-treated intermediate lobe of the rat pituitary gland. In this system, YN-09151-2 (calculated Ki of 10.5 nM) is equipotent with fluphenazine as a dopamine antagonist. In contrast, YM-09151-2 is not a potent antagonist of the dopamine-induced stimulation of adenylate cyclase activity of fish retina or the dopamine-stimulated accumulation of cAMP in a preparation of dispersed fish retinal tissue. These observations suggest that YM-09151-2 is a potent antagonist of the D2-dopamine receptor (in the classification schema of Kebabian and Calne) and that YM-09151-2 may be a useful tool in pharmacological investigations of the D1- and the D2-receptor.
The Role of Acid Catalysis in the Baeyer–Villiger Reaction. A Theoretical Study

Quantum mechanical calculations at the B3LYP/6-311+G(d,p) level have examined the overall mechanism of the Baeyer–Villiger (BV) reaction with peroxyacetic acid. A series of reactions that include both the addition step and the subsequent alkyl group migration step included ketones, acetone, t-butyl methyl ketone, acetophenone, cyclohexyl methyl ketone, and cyclohexyl phenyl ketone. The combined data suggested that the first step for addition of the peroxyacetic acid oxidation catalyst to the ketone carbonyl to produce the Criegee or tetrahedral intermediate is rate-limiting and has activation barriers that range from 38 to 41 kcal/mol without the aid of a catalyst. The rate of addition is markedly reduced by the catalytic action of a COOH functionality acting as a donor–acceptor group affecting both its proton transfer to the ketone C═O oxygen in concert with transfer of the OOH proton to the carboxylic acid carbonyl. The second or alkyl group migration step has a much reduced activation barrier, and its ...
Recent DØ results on the top quark

Abstract Recent results on top quark physics with the DO experiment in p p collisions at √s = 1.8 TeV for an integrated luminosity of 125 pb−1 are reported. The direct measurement of the top quark mass uses single lepton events, giving the result mtop = 173.3 ± 5.6(stat.) ± 6.2(syst.) GeV/c2. The measurement of the t t production cross section includes analyses from 8 top decay channels: dilepton ( t t → eμ, ee, and μμ ), electron and neutrino ( t t → eν ), and single leptons ( t t → e + jets and t t → μ + jets ) with and without b tagging. We measure the t t production cross section to be 5.5 ± 1.8 pb at mtop = 173.3 GeV/c2.
Using affinity chromatography to engineer and characterize pH-dependent protein switches

Conformational changes play important roles in the regulation of many enzymatic reactions. Specific motions of side chains, secondary structures, or entire protein domains facilitate the precise control of substrate selection, binding, and catalysis. Likewise, the engineering of allostery into proteins is envisioned to enable unprecedented control of chemical reactions and molecular assembly processes. We here study the structural effects of engineered ionizable residues in the core of the glutathione-S-transferase to convert this protein into a pH-dependent allosteric protein. The underlying rational of these substitutions is that in the neutral state, an uncharged residue is compatible with the hydrophobic environment. In the charged state, however, the residue will invoke unfavorable interactions, which are likely to induce conformational changes that will affect the function of the enzyme. To test this hypothesis, we have engineered a single aspartate, cysteine, or histidine residue at a distance from the active site into the protein. All of the mutations exhibit a dramatic effect on the protein's affinity to bind glutathione. Whereas the aspartate or histidine mutations result in permanently nonbinding or binding versions of the protein, respectively, mutant GST50C exhibits distinct pH-dependent GSH-binding affinity. The crystal structures of the mutant protein GST50C under ionizing and nonionizing conditions reveal the recruitment of water molecules into the hydrophobic core to produce conformational changes that influence the protein's active site. The methodology described here to create and characterize engineered allosteric proteins through affinity chromatography may lead to a general approach to engineer effector-specific allostery into a protein structure.
Phenylalanine ring dynamics by solid-state 13C NMR

Abstract The partial collapse of dipolar and chemical-shift tensors for carbons, both on and off the ring C2 symmetry axis of l -phenylalanine crystallized from two different solvent systems, confirms that a fraction of sites for one of the crystalline modifications permits high-frequency 180° ring flips. Analysis of the same tensors indicates the presence of other motions for both materials. These motions are reasonably well represented by a model involving restricted isotropic rotational reorientation, a motion which can be associated with looseness of packing in the crystals.
Purification and properties of l-valyl-sRNA synthetase from Escherichia coli

Abstract l -Valyl-sRNA synthetase ( l -valine:sRNA ligase (AMP), EC 6. i . i .9) has been purified from Escherichia coli by a procedure involving autolysis, (NH4)2SO4 fractionation, adsorption on and elution from calcium phosphate gel, and column chromatography. The enzyme, which is about 650-fold purified over the initial cell-free extract, is homogeneous on ultracentrifugation (sedimentation coefficient 4.2 S) and on polyacrylamide-gel electrophoresis. Certain general properties of the enzyme and the effect of various metal ions on its activity have been determined. The enzyme is inhibited by N- ethylmaleimide and p- chloromercuribenzoate . Preliminary studies of the enzyme sulfhydryl groups have been carried out.
Addition of carbon nucleophiles to arene-chromium complexes

Abstract The electrophilic reactivity of arenes coordinated to the chromium tricarbonyl unit has been developed into several distinct methods for coupling carbon nucleophiles with aromatic rings. Addition of the nucleophile produces stable η 5 -cyclohexadienyl chromium complexes which can be oxidized to induce loss of the endo hydrogen and the metal, overall nucleophilic substitution for hydrogen. Alternatively, the intermediate can be protonated and the resulting cyclohexa-1,3-diene can be detached from the chromium, effecting nucleophilic addition with reduction of one double bond. If a halogen (F, Cl) is present as a ring substituent, and if the nucleophile can migrate about the arene ligand, then loss of halide can occur parallel with classical nucleophilic aromatic substitution for halogen in electron-deficient haloarenes. With substituted arenes, the regioselectivity of addition becomes important and is often very high. Particularly useful are strong resonance donor substituents (RO-, R 2 N-, F-) where selectivity for meta attack is high. Indole provides an excellent example of selective activation, as the six-membered ring complexes selectively and is then susceptible to nucleophilic substitution, predominantly at the 4 and 7 positions. Substitution for halogen is a somewhat limited process and depends upon the nature of the nucleophile. Very reactive nucleophiles add to unsubstituted positions and are often slow to isomerize to the ipso position from which loss of halide can occur.
On-the-job training and rigidity of employment protection in the developing world: Evidence from differential enforcement☆

Abstract This paper analyzes the causal effect between strict employment protection regulations and the firm incentive to invest in job training of their employees. We explore a large firm level data set across several developing countries and assume that the rigidity of labor regulations affects more the investment decision of firms that faces a rigid enforcement of labor regulations. Our findings show that differences across countries in the enforcement of more rigid employment protection regulation are associated with very small differences in the investment in job training across firms. This finding is robust across several specifications and samples.
Angular symmetry of the ion scattering surface yield for large outerlayer relaxations

Abstract The calculated angular dependence of the ion scattering surface yield for incidence near the [101] axis of Au(110) is investigated as a function of first layer relaxation. A reversal of the asymmetry of the angular dependence is observed for both large contractions and large expansions. This reversal results from shadowing in the ion flux distribution near atoms along the [101] row.
The Test of Standard Written English and Resulting Placement Patterns: a Follow-Up of Performance of Older Upper-Division and Master Level Students

The Test of Standard Written English (TSWE) was designed for assessing the ability of students to use English. Published research has demonstrated that the TSWE has predictive validity for grades earned in freshman English and that the TSWE can be used for appropriate placement of students in the freshman English curriculum. Results of this validity study with the TSWE suggest that the use of the instrument can be generalized to older students entering at the juniors and master's degree level. The TSWE scores, resulting placement, and subsequent success in an English course, if required, were found to be predictive of academic performance for older, upper-division and masters level students in an environment with a restricted grading system.
On stability with large parameter variations: Stemming from the direct method of Lyapunov

A new approach with a computer algorithm for determining the "largest" upper bound for parameter variations of a linear constant coefficients system for which the system remains stable is established. This approach then provides the most efficient way of evaluating such "largest" variations of the coefficients of a stable polynomial.
Metals in the Hydrocycle

The authors state in the introduction that their purpose is to “give an account of the presently available knowledge on the movement of trace metals along the hydrologic cycle, emphasizing the processes.” In order to do this, they have divided the book into two parts. In the first part (chapters 2 and 3) they provide an overview of processes affecting speciation, adsorption/desorption, and diagenesis of trace metals. In the second part of the book, metal behavior in various environmental regimes (atmosphere, continental waters, estuarine and coastal waters, the ocean) is discussed.
4. Personality Profiles

Chapter 4 discusses the origins of the Dodge Morgan case study and the circumstances of his assessments. We present findings in the contexts of both the five-factor model (FFM) and the life-story model (LSM). We interpret Personality Research Form scale scores within the five-factor structure in order to create Morgan's FFM personality profile, which is supplemented with Thematic Apperception Test (TAT) data. We structure his LSM profile from multiple evaluations, including his TAT protocol and his earliest memories; from autobiographical data, including his published writings; and from additional biographical sources. Finally, we discuss the strengths and limitations of each theory and profile construction method.
A vibrational spectroscopic study of the ice-melting-induced transition of 1,2-dibehenoyl-sn-glycero-3-phosphocholine

Abstract The phase transition of bilayers of 1,2-dibehenoyl-sn-glycero-3-phosphocholine (DBPC) induced by ice (H2O and D2O) melting has been investigated by infrared and Raman spectroscopy. Spectral changes observed at this transition are smaller at lower water content. These spectral changes are interpreted in terms of increased molecular mobility. Slightly different temperature dependencies are observed for various spectral parameters between samples dispersed in H2O and D2O.
The growth of non-pyramidal neurons in the visual cortex of the rat: A morphometric study

Abstract In Golgi-Cox preparations, we have studied the 3-dimensional geometry and development of the perikarya and dendrites of non-pyramidal neurons in layer IV of the rat visual cortex with the aid of a semi-automated system. During the first postnatal week, non-pyramidal neurons are sparse and have small perikarya and undifferentiated dendrites. Their number increases substantially during the subsequent few days and reaches adult proportions by the end of the second week of postnatal life. A dramatic increase in the size of neuronal perikarya and elaboration of dendrites occurs from the middle of the first week to the end of the second week. The basic structure of the dendritic fields — as judged by the number of dendritic segments, the length of intermediate and terminal segments, the total length of the dendritic field, and the radial distance of the terminal tips from the center of the cell body — is achieved by the middle of the third postnatal week. The only growth which continues after this stage of development, and at least until day 90, is the elongation of the terminal dendrites. This and other studies indicate that the overall pattern of growth of pyramidal and non-pyramidal neurons is similar, and both cell types reach maturity at approximately the same stage of development. Measurements of non-pyramidal neurons in coronal, sagittal and tangential sections of visual cortex of developing and young-adult rats suggest that the perikarya and dendrites are oriented preferentially in the coronal plane and along an axis extending from the pial surface to the subcortical white matter.
The role of neuroticism on psychological and physiological stress responses.

This study examined the influence of personality on stressor appraisals and emotional, physiological, and behavioral responses to psychosocial stress. Appraisals were used to classify participants as threatened (they believed their coping resources were inadequate relative to stressor demands) or challenged (they believed their coping resources were commensurate with stressor demands). Neuroticism predicted threat appraisals, and both were related to negative emotional experience and poor task performance. The influence of neuroticism on negative emotions and poor performance was mediated by threat appraisals. High neuroticism confers stress vulnerability, but only when conditions are construed as threatening.
Metal-Surfactant Precipitation and Adsorption in Froth Flotation

Abstract Precipitation and adsorption of metal–surfactant on mineral surfaces control response in a large number of flotation systems. Systems comprising the four general mineral classifications are reviewed in this article. Conditions under which precipitation and adsorption occur are presented, and mechanisms of precipitate adsorption are discussed.
Unique type I interferon responses determine the functional fate of migratory lung dendritic cells during influenza virus infection

Migratory lung dendritic cells (DCs) transport viral antigen from the lungs to the draining mediastinal lymph nodes (MLNs) during influenza virus infection to initiate the adaptive immune response. Two major migratory DC subsets, CD103+ DCs and CD11bhigh DCs participate in this function and it is not clear if these antigen presenting cell (APC) populations become directly infected and if so whether their activity is influenced by the infection. In these experiments we show that both subpopulations can become infected and migrate to the draining MLN but a difference in their response to type I interferon (I-IFN) signaling dictates the capacity of the virus to replicate. CD103+ DCs allow the virus to replicate to significantly higher levels than do the CD11bhigh DCs, and they release infectious virus in the MLNs and when cultured ex-vivo. Virus replication in CD11bhigh DCs is inhibited by I-IFNs, since ablation of the I-IFN receptor (IFNAR) signaling permits virus to replicate vigorously and productively in this subset. Interestingly, CD103+ DCs are less sensitive to I-IFNs upregulating interferon-induced genes to a lesser extent than CD11bhigh DCs. The attenuated IFNAR signaling by CD103+ DCs correlates with their described superior antigen presentation capacity for naive CD8+ T cells when compared to CD11bhigh DCs. Indeed ablation of IFNAR signaling equalizes the competency of the antigen presenting function for the two subpopulations. Thus, antigen presentation by lung DCs is proportional to virus replication and this is tightly constrained by I-IFN. The “interferon-resistant” CD103+ DCs may have evolved to ensure the presentation of viral antigens to T cells in I-IFN rich environments. Conversely, this trait may be exploitable by viral pathogens as a mechanism for systemic dissemination.
Antimicrobial susceptibility of coagulase-negative Staphylococcus species isolated from bovine milk

Coagulase-negative Staphylococcus (CNS) isolates (n=168) obtained from milk from heifers and dairy cows were screened for minimum inhibitory concentration (MIC) to antimicrobials used commonly for mastitis therapy. Of the 10 CNS species included in the study, the predominant species were Staphylococcus chromogenes (n=61), Staphylococcus epidermidis (n=37), Staphylococcus hyicus (n=37), and Staphylococcus simulans (n=16). The majority of CNS was susceptible to ampicillin, oxacillin, cephalothin, and ceftiofur. Erythromycin and pirlimycin were also very effective in vitro inhibitors of CNS. The only exception was observed with S. epidermidis. Of 37 S. epidermidis evaluated, 13 (35%) exhibited efflux-based resistance to erythromycin (> or =16 microg/ml) encoded by msrA and one isolate carried ermC encoding ribosomal methylase-based resistance to both erythromycin (> or =64 microg/ml) and pirlimycin (> or =64 microg/ml). A total of 17 S. epidermidis, 11 S. chromogenes, and one S. hyicus exhibited phenotypic resistance to ampicillin (> or =0.5 microg/ml). Constitutive beta-lactamase production was observed in all ampicillin resistant isolates except 4 S. epidermidis that exhibited inducible beta-lactamase production. Induced beta-lactamase production was also observed in 13 S. epidermidis that were phenotypically susceptible to the entire MIC panel. All isolates that produced beta-lactamase either constitutively or by induction carried blaZ. S. epidermidis (n=12, 32%) that were resistant to methicillin (oxacillin > or =0.5 microg/ml) carried low affinity penicillin-binding protein encoded by mecA. Most multi-drug resistant (MDR) S. epidermidis (> or =2 resistance genes) were resistant to ampicillin, erythromycin and methicillin. All except one MDR S. epidermidis had icaAB, which encodes for polysaccharide intercellular adhesion. Based on pulsed field gel electrophoresis, MDR S. epidermidis were closely related genotypically, and were isolated from different cows on the same farm suggesting clonal dissemination. Bovine S. epidermidis share antimicrobial resistance patterns and virulence determinants of strains observed in human infections. Studying CNS at the species level can provide valuable information about species-specific differences that can be vital data for effective mastitis therapy and management.
Dose-rate dependence of the radiation-induced discoloration of polystyrene

Abstract Using a versatile Co-60 radiation aging facility, we have exposed commercial polystyrene samples to a series of dose rates ranging from 18 to 278 Gy/h at both 22°C and 60°C. For exposures in air, a diffusion-limited oxidation band occurs on the outsides of the samples; at a given dose rate, the thickness of this band is approximately independent of dose (up to at least 400 kGy). Modelling of the diffusion-limited oxidation allows us to estimate the oxygen consumed versus dose and dose-rate. Surprisingly, the results at 22°C indicate a “negative” dose-rate effect, where the consumption rate is lower at dose rates below ≈100 Gy/h than at dose rates above this level. Results from UV/VIS spectroscopy are consistent with this “negative” dose-rate effect, as are oxygen bleaching rates through non-oxidized regions of samples. Analyses of the bleaching rates allow quantitative estimates of the oxygen consumed during subsequent annealing of material aged under inert conditions. When air is present during irradiation, the oxygen consumption is approximately an order of magnitude greater than that measured during post-irradiation bleaching of inert samples. This indicates the likely existence of short-lived radicals which react with oxygen if it is present when they are formed.
Individual- and community-level predictors of victimization frequency in a sample of women exposed to IPV.

OBJECTIVE: The current study examines individual and community factors related to increased frequency of victimization in a sample of women with a history of intimate partner violence (IPV). The identification of unique and interactive associations of community- and individual-level factors and IPV frequency is rarely examined but may assist in developing services that are sensitive to the social-ecological context. METHOD: Women exposed to IPV in the past 2 years were interviewed (n = 120). Information about the communities in which they resided was drawn from the United States and Canadian censuses. Multilevel analyses nested women within their communities and examined the relationship of individual and community factors to frequency of victimization. RESULTS: Individual income, age, and educational attainment were negatively related to IPV frequency, with lowest victimization frequency for women living in communities with high educational attainment and income. CONCLUSIONS: It may be especially useful for organizations to focus on increased service delivery in under-resourced communities. Further, because young and low-income women are more likely to report increased frequency of violence, it may be helpful for clinicians to consider cohort-appropriate intervention methods and instrumental supports that reflect the specific needs of these women, such as employment support, child-care access, and financial management. Language: en