cssi/SciSciGPT-SciSciNet huggingface dataset:
Serum CTXii Correlates With Articular Cartilage Degeneration After Anterior Cruciate Ligament Transection or Arthrotomy Followed by Standardized Exercise.

Background:Anterior cruciate ligament injury increases risk for accelerated development of osteoarthritis. The effect of exercise on articular cartilage following joint injury is not well understood. Biochemical biomarkers of collagen degradation and proteoglycan turnover are potential indicators for early articular cartilage degeneration.Hypothesis:This study tests the hypothesis that serum concentrations of CS846 and CTXii correlate with structural changes to articular cartilage following joint injury in exercised animals.Study Design:Controlled laboratory study.Methods:Twenty-four Sprague-Dawley rats underwent either arthrotomy alone (sham surgery) or anterior cruciate ligament transection (ACLT). Animals were recovered for 3 weeks and then exercised on a treadmill at 18 m per minute, 1 hour per day, 5 days per week, until sacrifice either 6 or 12 weeks later. Articular cartilage was assessed grossly, and histology was graded using modified Mankin, toluidine blue, and modified David-Vaudey scales. Seru...
Hereditary dark teeth

Summary A clinical description of hereditary dark teeth is given, based on the examination of fifteen children with this condition. The teeth are abnormally dark, with the anterior teeth brown and translucent. They tend to lose enamel easily and to become worn down. The term “hereditary opalescent dentin” is most often used for this condition.
Gastric and cardiovascular effects of histamine in the dog

The H-2 receptor stimulation of gastric acid secretion and of heart rate by histamine, a mixed H-1–H-2 agonist, given in 45-min successive step doses 2–150 μg base/kg.h and 4(Me)histamine, (4(Me)H), 1.4 to 210 μg base/kg.h, a specific H-2 agonist, in five conscious gastric fistula dogs showed no difference between the agonists in ED50s or in maximal responses. The ED50 for acid was lower (15–16 μg/kg.h) than for cardiac chronotropism (25 to 27 μg/kg.h). Both effects were competitively antagonized by the H-2 antagonist cimetidine, 0.5 to 1 mg/kg.h. Background infusions of diphenhydramine, 2 mg/kg.h, raised the maximum heart rate increase caused by histamine from +108 to +149 beats/min (p<0.05) but not that of 4(Me)H; acid outputs were not augmented. Diphenhydramine 2 mg/kg.h alone caused no significant change in heart rate or blood pressure. Histamine reduced systolic blood pressure (SBP) by 48 mmHg and with diphenhydramine background by 61 mmHg (p<0.05). 4(Me)H at a top dose of 210 μg base/kg.h reduced SBP by 81 mmHg (p<0.05). To test whether the effects of added diphenhydramine could be interpreted as an H-1 receptor effect of histamine, the H-1 agonist 2-pyridylethylamine (PEA) was given alone (2–150 μg/kg.h in 45-min steps) or as a 100 μg/kg bolus during the infusion of 4(Me)H 50 μg/kg.h. There was no effect of PEA on gastric acid, heart rate or blood pressure. Even though diphenhydramine augments the effect of histamine on heart rate and blood pressure, the lack of PEA effect would indicate that there is not a direct H-1 receptor mediated effect on gastric acid, heart rate or systolic blood pressure in the conscious dog. This contrasts with published data obtained in anesthetized animals. After a single dose of 4(Me)H, 50 μg/kg.h had been infused i.v. for 45 min, acid output had reached 70% of the maximum seen at 90 min, heart rate had increased by 65% of its maximum response but SBP had not yet changed. Cimetidine blocked 4(Me)H-induced hypotension completely but blocked the heart rate increase only partially and competitively. We conclude that in the intact animal there is evidence for a direct H-2 mediated stimulation of heart rate in the conscious dog with kinetics similar to the H-2 stimulation of gastric acid secretion.
Enforcement of underage sales laws as a predictor of daily smoking among adolescents – a national study

With a goal to reduce youth smoking rates, the U.S. federal government mandated that states enforce laws prohibiting underage tobacco sales. Our objective was to determine if state compliance with tobacco sales laws is associated with a decreased risk of current daily smoking among adolescents. Data on tobacco use were obtained from a nationally representative sample of 16,244 adolescents from the 2003 Monitoring the Future survey. The association between merchant compliance with the law from 1997–2003 and current daily smoking was examined using logistic regression while controlling for cigarette prices, state restaurant smoking policies, anti-tobacco media, and demographic variables. Higher average state merchant compliance from 1997–2003 predicted lower levels of current daily smoking among adolescents when controlled for all other factors. The odds ratio for daily smoking was reduced by 2% for each 1% increase in merchant compliance. After controlling for price changes, media campaigns and smoking restrictions, a 20.8% reduction in the odds of smoking among 10th graders in 2003 was attributed to the observed improvement in merchant compliance between 1997 and 2003. A 47% reduction in the odds of daily smoking could be attributed to price increases over this period. Federally mandated enforcement efforts by states to prevent the sale of tobacco to minors appear to have made an important contribution to the observed decline in smoking among youth in the U.S. Given similar results from long-term enforcement efforts in Australia, other countries should be encouraged to adopt the World Health Organization Framework on Tobacco Control strategies to reduce the sale of tobacco to minors.
DESIGN AND SYNTHESIS OF POTENT IN VIVO ANTAGONISTS OF OXYTOCIN

We have previously shown that the substitution of 8-ornithine and 2-O-methyltyrosine alone and in combination in [1-deaminopenicillamine] oxytocin (dPOT) brought about enhancements in antagonistic potencies to responses to oxytocin in vivo. To explore the effects of these substitutions in analogs of dPOT containing larger alkyl substitutents on the beta carbon at position 1 and on the tyrosine residue at position two, the following six analogs were synthesized: [1-(beta-mercapto-beta, beta-diethylpropionic acid), 8-ornithine] vasotocin (1, dEt2OVT); (1-beta-mercapto-beta, beta-cyclopentamethylenepropionic acid), 8-ornithine] vasotocin (2, d(CH2)5OVT): [1-beta-mercapto-beta, beta-diethylpropionic acid), 2-O-methyltyrosine, 8-ornithine]vasotocin [3, dEt2 Tyr(Me)OVT]; [1-(beta-mercapto-beta, beta-diethylpropionic acid), 2-O-ethyltyrosine, 8-ornithine]vasotocin [4, dEt2 Tyr(Et)OVT]; [1-beta-mercapto-beta', beta-cyclopentamethylenepropionic acid), 2-O-methyltyrosine, 8-ornithine]vasotocin [5, d(CH2)5 Tyr(me)OVT]: [1-beta-mercapto-beta, beta-cyclopentamethylenepropionic acid), 2-O-methyltyrosine, 8-ornithine]vasotocin [6,d(CH2)5 Tyr(Et)OVT]. The required protected intermediates were synthesized by a combination of solid-phase synthesis and by individual 8 + 1 couplings in solution. All six analogs antagonize the actions of oxytocin on the rat uterus in the absence of Mg2+, in the presence of 0.5 mM Mg2+ and in situ. They also antagonize milk ejection responses to oxytocin, and the vasopressor responses to arginine vasopressin, and all have very low antidiuretic activities. With pA2 values of 7.35 +/- 0.08 and 7.37 +/- 0.17, respectively, compounds 3 and 5 are the two most potent in vivo antagonists of oxytocin reported to date.
Extensive polymorphisms observed in HIV–1 clade B protease gene using high–density oligonucleotide arrays

Naturally occurring mutations in HIV-1-infected patients have important implications for therapy and the outcome of clinical studies. However, little is known about the prevalence of mutations that confer resistance to HIV-1 protease inhibitors in isolates derived from patients naive for such inhibitors. In the first clinical application of high-density oligonucleotide array sequencing, the sequences of 167 viral isolates from 102 patients have been determined. The DNA sequence of USA HIV-1 clade B proteases was found to be extremely variable and 47.5% of the 99 amino acid positions varied. This level of amino acid diversity is greater than that previously known for all worldwide HIV-1 clades combined (40%). Many of the amino acid changes that are known to contribute to drug resistance occurred as natural polymorphisms in isolates from patients who had never received protease inhibitors.
Photodisintegration of Light Nuclei

Recent results of photodisintegration of deuteron and 3He measured with the CEBAF Large Acceptance Spectrometer at Jefferson Lab are reported. The onset of dimensional scaling is investigated in the two-body photodisintegration of 3He, with the results indicating a scaling onset at remarkably low energy and momentum transfer. Results on the azimuthal asymmetry of deuteron photodisintegration are expected to aid in understanding the dominant mechanisms of deuteron photodisintegration and the underlying dynamics in the medium-energy region. In this region, neither effective field theories nor perturbative QCD can be used to describe the reaction, and understanding the underlying dynamics is based on phenomenological quark models.
Modulation of 10.4 μ band CO2 laser radiation using the molecular Stark effect

Abstract Modulation of 10.4 μ carbon dioxide laser radiation has been obtained by the application of the Stark effect in several molecular absorbers. The depth of modulation obtained has been measured as a function of modulator gas pressure and incident light intensity. The results show an absence of saturation effects over the intensity range investigated.
Band-selective homonuclear dipolar recoupling in rotating solids

In this paper, we introduce approaches to band-selective homonuclear dipolar recoupling with the SPC-5 sequence described previously [Hohwy et al., J. Chem. Phys. 110, 7983 (1999)]. The technique, denoted SPC-53, restores the homonuclear dipolar coupling during magic angle spinning (MAS) and introduces a fifth-order residual offset term of controllable magnitude. The fifth order term truncates the dipolar coupling to spins that fall outside the operational bandwidth of the experiment. It is shown with high-order average Hamiltonian theory, multiple-spin simulations, and experiments, that polarization within a spin cluster can be propagated to destination spins with improved efficiency using this approach. Further, we show that a spin system subjected to band-selective recoupling obeys the equation of motion of the reduced spin cluster and that modeling of the polarization transfer process is simplified. Thus, in the important case of peptides and proteins, all of the backbone and side-chain carbonyl spins...
Gendering Comparative Politics: Achievements and Challenges

Approximately one-fifth, or 21%, of the members of the American Political Science Association identify themselves as comparativists, according to data in 2004. Among those affiliated with the APSA Women and Politics Research Section, the corresponding figure is nearly one-third, or 31% (Tripp 2010, 192). While not a majority, these patterns suggest that gender and politics scholars have been attracted in greater proportions to this particular subfield. The reasons for this, Karen Beckwith (2010) has noted, are linked to features of comparative politics particularly conducive to work on gender: an interest in answering “real world” questions, a lack of a hegemonic research agenda making the subfield more open to new topics, an emphasis on methodological pluralism valuing the contributions of qualitative and case study analysis, and a stress on fieldwork as an important vehicle for data collection.
Four measures of visual imagination

Abstract The present investigation examined intercorrelations among four measures thought to be related to an individual's ability to imagine visual scenes. The measures included Self-Rating of ability to imagine visual scenes, improvement in paired associate learning when instructed to use visual images as mnemonic aids (Recall Improvement), respiratory changes associated with the imagining of fearful scenes, and a test involving memory for the location of objects in a picture (Picture Memory). Significant correlations were obtained between Self-Rating and respiratory change, Picture Memory and respiratory change, and Picture Memory and Recall Improvement. The value of Self-Rating and Picture Memory as prognostic devices for desensitization was discussed, and it was concluded that Picture Memory may prove to be the superior of the two.
Biological foundations of cerebral dominance

Abstract A conference entitled ‘Biological Foundations of Cerebral Dominance’ was held on 4–6 April in Boston, under the joint sponsorship of the Harvard Department of Neurology at the Beth Israel Hospital and the Institute for Child Development Research. The purpose of the meeting was a unified presentation of the recently developed biological approaches to the study of cerebral laterality. Report by Norman Geschwind.
Association of reliability with reproducibility of the glaucomatous visual field

We studied 207 glaucoma patients (207 eyes) who had two successive visual tests on the Humphrey Field Analyzer to determine the association of unreliability (> 10% incidence of a missed catch trial test) with threshold variation. We found that in patients where one visual field showed > 30% false negative or positive errors, and the other visual field also was unreliable, a significant increase in the variance of the mean defect existed from reliable patients (p < 0.05). Of patients who had only one of two visual fields which was unreliable (from false negative errors), only those with marked glaucomatous visual field loss (< -15 dB depth of defect) showed a greater variance in mean defect between examinations over reliable patients (p < 0.05). In total, 41 patients (19.8%) had unreliable visual fields associated with statistically increased threshold variation. This study suggests that patient reliability should be considered when interpreting changes in threshold between automated visual field examinations.
Professional Women's Well-Being: The Role of Discrimination and Occupational Characteristics

This study examined the association between perceived discrimination, workplace racial composition, and three outcomes—psychological distress, life dissatisfaction, and job dissatisfaction—among a sample of Black (n = 72) and White (n = 74) professional women. As a comparison, these relationships were analyzed to determine if they varied from those observed in more traditionally studied populations: Whites and non-professional Blacks, using data from a population of working women in the 1995 Detroit Area Study (N = 533). Perceived discrimination was associated with differences in psychological distress and job dissatisfaction but not with life dissatisfaction. The correlation between perceived discrimination and psychological distress was larger for White professional women than for Black professional women (White women odds ratio [OR]: 1.99; Black women OR: 0.80). A larger correlation between race and job dissatisfaction was observed for Black professional women than for Black non-professional women. The...
The I, I′, and I″ absorption bands of O2 in the region 790–865 Å

Abstract The absorption spectra of 16 O 2 and 18 O 2 in the wavelength region 790–865 A have been photographed with a 6.65-m vacuum spectrograph. The bands are diffuse and most of them are classified as members of three vibrational progressions, I, I ′, and I ″, which originate from the v = 0 level of the ground state of oxygen. Absolute vibrational quantum number assignments are made for each of these progressions based on isotope shift analysis, and the vibrational constants of their upper electronic states are reported for 16 O 2 and 18 O 2 . The similarity in vibrational constants between these electronic states and those for the a 4 Π ui state of O 2 + , as well as their quantum defects suggest that they are Rydberg states. In addition, the magnitude of their spin-orbit splitting and the rotational structure for some of these bands indicate that the upper electronic state for each of these three progressions has 3 Π u symmetry.
Local attitudes on regional ecosystem management: a study of New Jersey Pinelands residents

The objective of this article is to examine the attitudes of southern New Jersey residents (n = 401) to a regional ecosystem management plan, the Pinelands Comprehensive Management Plan. The research questions focus on the association between residents’ socioeconomic characteristics and interaction with the plan, and their level of support for it. The results indicate that approximately half of the respondents support the planning efforts. Significant correlations between education level, environmental group membership, and familiarity with the planning efforts and the level of support were found. These results are detailed by the logistic regression analysis, which identifies subgroups within the sample of respondents. Contextual variables, particularly familiarity and direct interaction with the management activities, prove to be the important predictors of individuals’ support of the planning efforts. Spatially defined variables, particularly location of residence, prove to be of limited importance.
First-principles time-dependent simulation of laser assisted desorption of hydrogen atoms from H–Si(111) surface

The dynamics of hydrogen desorption from H-terminated silicon surface clusters has been simulated in the framework of real space time-dependent density functional theory complemented with molecular dynamics for ions. It has been demonstrated that by choosing an appropriate frequency and intensity of the laser it is possible to remove the hydrogen layer from the surface without destroying the structure of underlying silicon. At the laser field intensities used in the current study (0.5–2.0 V/A) the desorption process is notably nonlinear.
Isolation and Identification of 11-Ketoprogesterone, 11-Hydroxyprogesterone and 11-Hydroxyandrostenedione in Canine Adrenal Vein Blood1

Three hitherto unidentified Δ4-3-ketosteroids were isolated from pooled canine adrenal vein blood. By such criteria as mobility in different solvent systems of paper chromatography, sulfuric acid and infrared spectra the isolated compounds were identified as 11-ketoprogesterone, and 11-hydroxyprogesterone, and 11-hydroxyandrostenedione.
Computational study of the cycloaddition reactivity of the osmium silylyne

Abstract The [2+2] cycloaddition reactivity of an osmium silylyne compound 2 , [Cp ∗ ( i Pr 3 P)(H)Os Si(Trip)][HB(C 6 F 5 ) 3 ], with PhC CPh or P C t Bu was studied by density functional theory (DFT) computations. Results indicate that these two reactions are under kinetic control in room temperature and the kinetic products were detected by NMR in experiments. Further tests revealed that the interplay between steric effects and the bonding interactions between two reacting fragments is majorly responsible for the energy differences in different isomers.
Impact of birth weight on ethnic variations in subcutaneous and central adiposity in American children aged 5-11 years. A study from the Third National Health and Nutrition Examination Survey.

OBJECTIVE: To determine the types of subcutaneous adiposity represented by different measurements of skinfold thickness that are associated with birth weight in white (n=759), Black (n=916) and Hispanic (n=813) American children aged 5–11 y. We also determined the contribution of birth weight to ethnic differences in subcutaneous and central adiposity. DESIGN AND METHODS: Data for this analysis were from the Third US National Health and Nutrition Examination Survey. The outcome measures were triceps, subscapular, suprailliac and thigh skinfold thicknesses at 5–11 y of age. Central adiposity was defined as ratios of subscapular to triceps (STR) and central–peripheral (CPR) (subscapular+suprailliac)/(triceps+thigh) skinfolds. Partial correlation analyses were used to determine the association between birth weight and measures of subcutaneous fatness, while multiple linear regression analyses were used to determine the independent contribution of birth weight to ethnicity variations in subcutaneous and central adiposity adjusting for sex, age and BMI. RESULTS: Overall, birth weight was negatively associated with subscapular skinfold and central adiposity in White, Black and Hispanic American children (P<0.05). Birth weight was also negatively associated with suprailliac skinfold in both Blacks and Hispanics (P<0.01) and with sum of the four skinfolds in Blacks (P<0.05). Compared with White, Black ethnicity was negatively associated with triceps, suprailliac thigh and sum of skinfold thicknesses controlling for birth weight, sex, age and BMI (P<0.01). Compared with White, Hispanic ethnicity was negatively associated with triceps, thigh and sum of skinfold thicknesses (P<0.01). Both Black and Hispanic ethnicity was positively associated with STR and CPR (P<0.01). CONCLUSIONS: In this population of American children, the association of birth weights with subcutaneous and central fat accumulation may be due to fetal programming. Since the impact of fetal conditions is likely to be modified by life course, defining the interaction between factors that are present at birth and subsequent exposures is one of the essential challenges for future research.
Natural convection flow and heat transfer between a fluid layer and a porous layer inside a rectangular enclosure

Etude numerique et experimentale. Modelisation de l'ecoulement dans la couche poreuse a l'aide de l'equation de Darcy etendue par Brinkman et Forchheimer. Verification experimentale sur des ecoulements d'eau et de glycerine dans un milieu constitue de billes de verre
Reliability-based Seismic Design of Wood Shear Walls

This paper reports on work, conducted under Task 1.5.3 (Reliability Studies) of the CUREE-Caltech Woodframe Project, with the objective of developing a risk-based methodology for seismic design of shear walls. Along with diaphragms, shear walls are primary lateral force resisting components in woodframe structures. The methodology developed herein is based on reliability principles as well as emerging performance-based concepts for seismic design. The specific subobjectives of Task 1.5.3 were: (1) to conduct a sequence of sensitivity studies to evaluate the contributions of various sources of uncertainty to shear wall performance as predicted using the CASHEW program (developed in another task of the project); (2) to evaluate the variabilities in, and thereby statistically characterize, the peak response obtained using a suite of ordinary ground motion records taken to characterize the seismic hazard in southern California; and (3) to develop a risk-based procedure for performance-based design of wood she...
Natural abundance 17O NMR spectroscopy of heterocyclic N‐oxides and Di N‐oxides. Structural effects

The 17O chemical shift data for a series of azine N-oxides, diazine N-oxides and di-N-oxides at natural abundance are reported. Isomeric methyl substituted quinoline N-oxides exhibited chemical shifts which are interpreted in terms of electronic and compressional effects. The 17O chemical shift for 8-methylquinoline N-oxide (370 ppm) is deshielded by 25 ppm more than predicted, based upon electronic considerations. The 17O chemical shift for the N-oxide of 8-hydroxyquinoline (289 ppm) is substantially shielded as a result of intramolecular hydrogen bonding. The relative 17O chemical shifts for diazine N-oxides of pyrazine, pyridazine and pyrimidine follow predictions based on back donation considerations. Because of solubility limitations, spectra of only two N,N′-dioxides were obtained. The chemical shift of benzopyrazine di N-oxide in acetonitrile was shielded by 18 ppm compared to that of its mono N-oxide.
Infant cry as a graded signal: Experimental modifications of durations of pauses and expiratory sounds alter mothers' perceptions

The purpose of this study was to examine experimentally the effects of the temporal structure of infant crying on mothers' perceptions. Eighteen mothers of young infants rated variations of a 10-sec cry in which durations of all expiratory sounds and pauses were digitally lengthened and shortened by 50%. Results showed a general monotonic effect in which cries with increasingly shorter pauses were perceived to be more arousing, aversive, informative, and rough. Similarly, cries with short expirations were perceived to be more rhythmic and rough than cries with long expirations. The strength of the monotonic effect for pause duration on ratings of urgency interacted with the duration of expiratory sounds such that the combination of short pauses and short expirations created the greatest perceived urgency. This study replicates and extends previous findings which show that gradations in acoustic features of crying are associated with gradations in the intensity of adults' perceptions.
An efficient scheme for convection-dominated transport

Partial differential equations describing transport processes involving a significant effect of the flow velocity may be solved efficiently and easily, using a simple algorithm. The algorithm is based on the propagator(s) (or Green's functions) for the equations of transport theory. The numerical method employed is always at least as fast as finite differencing, and it reduces to a finite difference method in the short time-step limit, but is especially efficient in cases where flow dominates over diffusion and is consequently widely applicable in kinetic theory and fluid dynamics. Using this method, the ion distribution function and the potential in a plasma sheath were calculated in the presence of charge exchange collisions for a wide range of neutral densities.
Fatigue behavior of A356/357 aluminum cast alloys. Part II – Effect of microstructural constituents

Abstract A quantitative study of the interactions between microstructural features such as secondary dendrite arm spacing (SDAS), eutectic structure, matrix strength, and fatigue behavior of two Al–7% Si–Mg casting alloys with magnesium contents of 0.4% and 0.7%, respectively, has been conducted. In the absence of casting defects, the influence of microstructural features on the fatigue performance becomes more pronounced. The degree and rate of microdamage (microcracking) is strongly affected by the strength of the matrix, and especially by the eutectic particle size, morphology, and distribution (clustering). A soft matrix (under-aged alloys) will generate more local microdamage compared to a peak-aged one. Large and elongated eutectic particles present in unmodified alloys result in lower fatigue lives. A decrease of fatigue life with increasing Mg and Fe content is observed, mainly due to the increased sizes of Fe-rich intermetallic particles. Microstructures with similar eutectic particle size and morphology as the Sr-modified ones, show a minimum fatigue life at intermediate SDAS values (∼60 μm), which is related to the continuity of particles on the dendrite cell boundaries. For coarser microstructures ( SDAS >60 μ m), the increase in fatigue life is attributed to the reduced damage rate along the cell boundaries.
Interaction of iodine species with glycogen at high concentrations of iodine

Glycogen–iodine (GI) complex formation has been studied at different concentrations of iodine and glycogen. For each glycogen concentration (0.25, 0.125, 0.0625, 0.0313 g/L), the iodine concentration was varied from 0.0317 to 1.59 g/L and the absorbance readings were taken at 453 and 560 nm (GI wavelengths of maximum absorbance). The 453 nm absorbance curves for the GI solution (GI complex and unreacted iodine), and that of the pure iodine solution (without glycogen) level off at a high iodine concentration, and give a peak in the subtracted curve. The 560 nm curves consistently increase in absorbance, and no peak is noticed in the subtracted curve. The spectra of concentrated iodine solutions in water and alcohol suggest the formation of neutral iodine clusters. We suggest that these iodine clusters do not react with glycogen, and that the GI complex formation takes place by the addition of I2 molecules. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 927–931, 1997
Diffusion of hydrogen, deuterium, and tritium on the (100) plane of copper: Reaction-path formulation, variational transition state theory, and tunneling calculations

Abstract We have applied variational transition state theory in a reaction-path formulation, using semiclassical methods of calculating multidimensional tunneling probabilities, to the surface diffusion of H, D, and T on the (100) surface of fcc Cu cover the temperature range 100–1000 K using the empirical pairwise interaction potential of Gregory, Gelb, and Silbey. We show that the reaction-path formalism offers a tractable way to deal with multidimensional motion of an adsorbate across a many-atom substrate. Our calculations show that the variational transition states for these systems are located at the saddle point for all temperatures studied. We find very large quantal effects, due to zero point quantization and tunneling, with the largest effects, over four orders of magnitude, for H at 100 K. At this temperature, tunneling alone increases the surface diffusion coefficient by three orders of magnitude. Even at 140 K, the tunneling effect increases the surface diffusion coefficients of H, D, and T by factors 3.0, 1.6, 1.3, respectively. Unfortunately, there are no experimental data available for this system for comparison, but in light of the very large quantal effects, we are encouraged by the reasonably good agreement of our results for T ⩾ 110 K with those of Valone, Voter, and Doll, who included quantal effects by a completely different method.
Predicting the accuracy of visual search performance in the structural inspection of aircraft

Abstract The predominant tasks in aircraft inspection are those that require visual search. Speed and accuracy characterize visual search tasks. Since the trade-off between speed and accuracy directly affects the safety, dependability and affordability of air transportation, there is considerable motivation to express this relationship in quantitative terms. Although models of this trade-off have been previously proposed for various search tasks, the applicability of these models to the tasks typically required of aircraft inspectors is limited. Thus new models of visual search that typify aircraft inspection are adopted here in order to examine the explicit trade-off between speed and accuracy in this environment. Relevance to industry The models adopted here, specifically applicable to aircraft inspection, consider the trade-off between speed and accuracy – a trade-off that ultimately affects the affordability, dependability, and safety (and therefore public perception of) air travel – in quantitative terms. These models also define the extent to which accuracy can be improved.
Global infectious disease surveillance and health intelligence.

Current concerns about the spread of infectious diseases, especially unexpected (“emerging”) infections such as pandemic influenza or severe acute respiratory syndrome (SARS), have renewed focus on the critical importance of global early warning and rapid response. Although considerable progress has been made, many gaps remain. A number of the gaps can be addressed through increased political will, resources for reporting, improved coordination and sharing of information, raising clinicians’ awareness, and additional research to develop more rigorous triggers for action. The increasing availability of communications and information technologies worldwide offers new opportunities for reporting even in low-capacity settings.
Hierarchy-aware algorithms for CDN proxy placement in the Internet

The wide adoption and explosive growth of the Internet has led to increasing demand for near instantaneous response from users. Caching is an important avenue to save network bandwidth, reduce server load and the response time experienced by web clients. Content Distribution Networks (CDNs) have emerged as a powerful solution to improve the client response time and to reduce the traffic in the Internet. CDNs consist of a set of distributed proxy servers replicating the content for better performance and availability than centralized servers. The key factor in determining the effectiveness of a CDN is the placement of proxy servers. Network topology and routing policies play an important role on the effectiveness of proxy server placement. However, existing studies on proxy server placement either consider simplified topology (i.e. tree topology) or focus on a particular snapshot of Internet topology. In addition, none of the studies have taken into consideration of the routing policies imposed by Internet Service Providers (ISPs), which is crucial in determining the performance of web access. In this paper, we present heuristic algorithm for CDN proxy server placement by taking into account the hierarchical Internet structure and the routing policy constraint resulting from it. Our experimental results on the Internet topology over three years show that the heuristic algorithms adapt to the Internet growth well.
Cerebral Blood Flow during Hypoxemia and Hemodilution in Rabbits: Different Roles for Nitric Oxide?

Hypoxemia and anemia are associated with increased CBF, but the mechanisms that link the changes in Pao2 or arterial O2 content (Cao2) with CBF are unclear. These experiments were intended to examine the contribution of nitric oxide. Cao2 in pentobarbital-anesthetized rabbits was reduced to approximately 6.5 mL O2/dL by hypoxemia (Pao2 approximately 24 to 26 mm Hg) or hemodilution with hetastarch (hematocrit approximately 14% to 15%). Animals with normal Cao2 (approximately 17.5 to 18 mL O2/dL) served as controls. In part I, each animal was given 3, 10, and 30 mg/kg Nω-nitro-l-arginine methyl ester (l-NAME) intravenously (total 43 mg/kg) to inhibit production of nitric oxide. Forebrain CBF was measured with radioactive microspheres approximately 15 to 20 minutes after each dose. Baseline CBF was greater in hypoxemic rabbits (111 ± 31 mL·100 g−1·min−1, mean ± SD) than in hemodiluted (70 ± 22 mL·100 g−1·min−1) or control animals (39 ± 12 mL·100 g−1·min−1). l-NAME (which reduced brain tissue nitric oxide syn...
Context switch overheads for Linux on ARM platforms

Context switching imposes a performance penalty on threads in a multitasking environment. The source of this penalty is both direct overhead due to running the context switch code and indirect overhead due to perturbation of caches. We calculate indirect overhead by measuring the running time of tasks that use context switching and subtracting the direct overhead. We also measure the indirect overhead impact on the running time of tasks due to processor interrupt servicing. Experiment results are presented for the Linux kernel running on an ARM processor based mobile device platform.
Open Systems Interconnection Abstract Syntax Notation: ASN.CG

Open Systems Interconnection (OSI) enables communication between computers using a common set of protocols (rules) and structured data [5,9]. ASN.1 (Abstract Syntax Notation One) is a formal notation allowing communication between two different (or same) computer systems; each system agrees on what the data will mean when transmitted even though each system can choose its own local representation of the exchanged information [3]. ASN.1 has several drawbacks including usability of the language and its macro facility.
Senrad: an advanced wideband air-surveillance radar

The generic characteristics and performance of an experimental long-range air-surveillance radar, known at the Naval Research Laboratory as Senrad, is described. Its distinguishing feature is that it can operate with simultaneous transmissions over a very wide bandwidth-from 850 to 1400 MHz. The technology and type of experimental radar equipment employed are discussed and examples are given of its performance capabilities obtained by means of very wideband operation. The unusually wide bandwidth of this radar allows 1) improved detection and tracking performance because of the absence of the nulls that are common in the antenna elevation radiation-pattern of a single-frequency radar; 2) moving target indication (MTI) without loss of targets due to blind speeds and without the need for multiple PRFs (pulse repetition frequencies); 3) accurate height finding with a fan-beam radar by taking advantage of the multipath time difference as a function of target height; 4) a form of limited target recognition based on high range-resolution; and 5) a reduction of the effectiveness of electronic countermeasures that can seriously degrade more narrowband radars.
QUALITATIVE VARIABLE DISCRIMINANT ANALYSIS AND ITS USE IN PRODUCT VERSION SELECTION

The purpose of this article is to illustrate the use of multiple discriminant analysis in those cases in which all discriminating variables are qualitative. The authors will show that an appropriate qualitative variable discriminant analysis model is a reformulation of the Bayesian decision theoretic model. Rules for the use of multiple discriminant analysis also are suggested for the cases in which some variables are qualitative and some are measurable on at least an interval scale. The qualitative variable discriminant analysis model is illustrated as an appropriate device for selecting a product version that will minimize a manufacturer's risk of product introduction.
Survey of heavy metal contamination in recycled polyethylene terephthalate used for food packaging

Polyethylene terephthalate food-product containers made with post-consumer materials have been found contaminated with heavy metals due to the recycling and sorting process. The increased use of recycled plastic flake from international suppliers, and subsequent commingling with electronic waste, has been suspected as the source of the increased levels of heavy metal contamination. In this study, nickel, chromium, cadmium, antimony, and lead were quantified in post-consumer polyethylene terephthalate extruded sheet and thermoformed samples, using inductively coupled plasma-atomic emission spectrometry. Recycled polyethylene terephthalate samples were digested using trace-metal grade hydrochloric, perchloric, and nitric acids. Samples were analyzed per ASTM E1613-04, standard test method for determination of lead by inductively coupled plasma atomic emission spectrometry, flame atomic absorption spectrometry, or graphite furnace atomic absorption spectrometry techniques. Two hundred samples were tested of ...
Case Studies of Aerosol Retrievals over the Ocean from Multiangle, Multispectral Photopolarimetric Remote Sensing Data

To evaluate the global effects of aerosols on the direct radiative balance, tropospheric chemistry, and cloud properties of the earth’s atmosphere requires high-precision remote sensing that is sensitive to the aerosol optical thickness, size distribution, refractive index, and number density. This study uses the multiangle 0.41-, 0.55-, 0.865-, and 2.25-mm channel data from the airborne Research Scanning Polarimeter to retrieve aerosol properties over the Pacific Ocean. It is shown that such photopolarimetric data are highly sensitive to the size distribution and refractive index of aerosol particles, which reduces the nonuniqueness in aerosol retrievals using such data as compared with less comprehensive datasets. Moreover, it is found that polarized reflectances obtained at the shorter wavelengths (0.41 and 0.55 mm) are significantly less sensitive to the contribution of the ocean’s upwelling light than total reflectance measurements, providing a natural tool for the separation between the estimation of oceanic and atmospheric scattering properties.
Basic Science Faculty in Surgical Departments: Advantages, Disadvantages, and Opportunities

The number of Ph.D. faculty in clinical departments now exceeds the number of Ph.D. faculty in basic science departments. Given the escalating pressures on academic surgeons to produce in the clinical arena, the recruitment and retention of high-quality Ph.D.s will become critical to the success of an academic surgical department. This success will be as dependent on the surgical faculty understanding the importance of the partnership as the success of the Ph.D. investigator. Tighter alignment among the various clinical and research programs and between surgeons and basic scientists will facilitate the generation of new knowledge that can be translated into useful products and services (thus improving care). To capitalize on what Ph.D.s bring to the table, surgery departments may need to establish a more formal research infrastructure that encourages the ongoing exchange of ideas and resources. Physically removing barriers between the research groups, encouraging the open exchange of techniques and observations and sharing core laboratories is characteristic of successful research teams. These strategies can meaningfully contribute to developing successful training program grants, program projects and bringing greater research recognition to the department of surgery.
Attention in the temporal domain: a phase-coding mechanism controls the gain of sensory processing

We are constantly confronted with more information than our sensory systems, limited in resources, can effectively process. Selective attention is the means by which our brain prioritizes the processing of behaviorally relevant information. Recent work in the visual domain indicates that it relies on a large variety of physiological mechanisms. At the single cell level selective attention is reflected by increased firing rate (Spitzer et al., 1988) and/or enhanced synaptic efficacy (Briggs et al., 2013). At the population level, the synchrony, variability, correlation structure, pooling efficiency, and/or response gain of neural activity is modulated (for a comprehensive overview of these mechanisms see Serences, 2011). The extent to which these mechanisms can operate independently from each other is not known. To disambiguate this important issue, researchers try to identify and study each possible parameter and dimension that might play a role in selective attention. For instance, attention either acts by modulating sensitivity to the content of a stimulus (feature-based attention), or to the frame in which it is embedded, through spatial and temporal attention (Nobre et al., 2012). Although feature-based and spatial attention have since long ago been a subject of intense investigation (Carrasco, 2011) temporal attention has historically received little emphasis, in spite of its ubiquitous presence. Two recent studies from Prof. Nobre's group at Oxford University, comprised of a behavioral experiment (Rohenkohl et al., 2012) and its EEG-recording counterpart (Cravo et al., 2013), provide new evidence that temporal attention (expectation) affects early stages of visual processing and uncover how these effects are implemented at the neural level.
Perinatal Blockade of B7-1 and B7-2 Inhibits Clonal Deletion of Highly Pathogenic Autoreactive T Cells

A number of in vitro studies have suggested that costimulatory molecules B7-1 and B7-2 and their receptor CD28 can promote clonal deletion, and limited in vivo studies have indicated that CD28 is involved in the clonal deletion of some T cells. However, the significance of B7-mediated clonal deletion in preventing autoimmune diseases has not been studied systematically. Here we report that the perinatal blockade of B7-1 and B7-2 substantially inhibits the clonal deletion of T cells in the thymus and leads to an accumulation of T cells capable of inducing fatal multiorgan inflammation. These results reveal a critical role for costimulatory molecules B7-1 and B7-2 in deleting pathogenic autoreactive T cells in the thymus. The critical role of B7-1 and B7-2 in T cell clonal deletion may explain, at least in part, the paradoxical increase of autoimmune disease in mice deficient for this family of costimulatory molecules, such as cytotoxic T lymphocyte associated molecule 4, CD28, and B7-2. The strong pathogenicity of the self-reactive T cells supports a central hypothesis in immunology, which is that clonal deletion plays an important role in preventing autoimmune diseases.
Post-transplant repopulation of naïve and memory T cells in blood and lymphoid tissue after alemtuzumab-mediated depletion in heart-transplanted cynomolgus monkeys.

Repopulation of memory T cells (Tmem) in allograft recipients after lymphodepletion is a major barrier to transplant tolerance induction. Ineffective depletion of naive T cells (Tn) and Tmem may predispose to repopulation of Tmem after transplantation. Cynomolgus macaque monkeys given heart allografts were lymphodepleted using Alemtuzumab (Campath-1H; anti-CD52). Peripheral blood (PB) and lymph nodes (LN) were analyzed for CD95(-) (Tn) and CD95(+) cells (Tmem), one day, one month and up to three months after Alemtuzumab infusion. CD52 expression, susceptibility to Alemtuzumab cytotoxicity and pro-apoptotic caspase-3 were evaluated in Tn and Tmem. In vivo, Alemtuzumab induction profoundly depleted lymphocytes in PB (99% reduction) but exerted a lesser effect in LN (70% reduction), with similar depletion of Tn and Tmem subsets. After transplantation, Tmem comprised the majority of lymphocytes in PB and LN. In vitro, LN T cells were more resistant to Alemtuzumab-mediated cytotoxicity than PB lymphocytes. CD4(+) Tn and Tmem were equally susceptible to Alemtuzumab-mediated cytotoxicity, whereas CD8(+) Tn were more resistant than CD8(+) Tmem. However, no significant differences in CD52 expression between lymphocyte subsets in PB and LN were observed. Caspase-3 expression was higher in PB than LN T cells. CD4(+) and CD8(+) Tn expressed lower levels of Caspase-3 than Tmem, in both PB and LN. Thus, after Alemtuzumab infusion, residual Tn in secondary lymphoid tissue may predispose to rapid recovery of Tmem in allograft recipients.
Optimizing endocrine therapy for breast cancer.

to patients in place of tamoxifen, or as part of a sequential treatment strategy. Further analysis of completed trials, as well as results of ongoing and future studies, will provide critical answers that may translate into further improvements in care for postmenopausal women with receptorpositive disease. More than 2,000 postmenopausal women are diagnosed with receptor-positive disease each week in the United States alone; the impact of any improvements in the care of these patients could have significant public
Numeric Simulations of a Novel Wideband Electromagnetic Band Gap Metamaterial Utilizing Oriented Cobalt-Substituted Z-Type Barium Hexaferrites

The material parameters of an electromagnetic bandgap (EBG) metamaterial consisting of metallic Sievenpiper structures prepared upon a Co2Z hexaferrite substrate having μr = 12 to 14 and er = 10 to 12 are reported. A bandwidth of 50%-75% of L-band was realized in simulation. The synthesis of the Co2Z hexaferrite material with optimized properties was achieved via a modified aqueous coprecipitation method with yields of up to 25 g/L. Magnetically oriented Co2Z substrates were demonstrated to exhibit a zero-field ferromagnetic resonance frequency of ~1.1 GHz that enabled device application from ultrahigh frequency (UHF) through L-band frequencies. EBG metamaterials designed and simulated on an oriented Co2Z hexaferrite substrate were compared to standard dielectric EBG designs. Results indicate that standard dielectric EBG designs, which operate over a 50% bandwidth and profile height of ~λo/10, are replaceable with an equivalent bandwidth Co2Z EBG metamaterial designed to a height of ~λo/95. The applications of the proposed metamaterial toward ultralow profile antenna designs at UHF through L-band are discussed.