cssi/SciSciGPT-SciSciNet huggingface dataset:
Parametric Stability Analysis of Nonlinear Rotating Blades

The role of the “geometric stiffening” nonlinearities played in the stability analysis of a rotating beam is investigated. It is a well established fact that nonlinear theory must be employed to capture geometric stiffening effect, which has been extensively investigated. In this work, two models are built for a rotating blade with periodically perturbed rotation rate, one is the “effective load” linear model and the other is “geometric stiffening” nonlinear model. Both of these two models are discretisized via Galerkin’s method and a set of parametric excited gyroscopic equations are obtained. The dynamic stability of these two models are studied and compared by the generalized harmonic balance method.Copyright © 2011 by ASME
TU‐E‐224A‐03: Image and Dosimetric Verification of Positioning Accuracy for Helical Tomotherapy Intensity Modulated Stereotactic Radiosurgery

Purpose: To investigate the accuracy of Helical Tomotherapy for intracranial radiosurgery using Mega‐voltage CT (MVCT) image fusion. Method and Materials: Tomotherapy generates a set of MVCT images which are fused to the treatment planning KVCT to facilitate the patient setup. For intracranial lesions, mutual information matching program using bony anatomy automatically generates the lateral, longitudinal, vertical, pitch, roll and yaw adjustments that are necessary to align the MVCT to KVCT images. In our study, a pReference head phantom immobilized by Nomos Talon system was used to verify the positioning accuracy of MVCT fusion. Three gold‐filled titanium markers inside the head phantom and the localization tip in the Talon system were used as the independent imaging makers to verify the MVCT positioning accuracy. In addition, dosimetric analysis was performed with a 0.015cc pinpoint ion chamber placed inside the phantom during KVCT simulation. A tomotherapy SRS plan with ion chamber sensitive volume as the target was generated and delivered. After MVCT to KVCT auto registration, dosimetric profiles in three directions were measured by stepping the couch away from the registered position. If the registration was perfect, the dose profile peak position should correspond to the registered position. The distance from the maximum dose to the registered location provides the ultimate accuracy of the system, including MVCT imaging accuracy and radiation dose delivery accuracy. Results: The average localization differences between the MVCT and KVCT were 0.92mm in lateral, 0.82mm in longitudinal and 0.60mm in vertical directions. Dosimetric measurements showed 1.3mm offset laterally and 0mm offset in the other two directions. The relative large setup error in the lateral direction is partially due to the manual couch adjustment with mechanical scale in that direction. Conclusions: The MVCT image fusion can be used to setup SRS patients within accuracy comparable to the current SRS standard.
Effects of reservoir anaerobic, reducing conditions on surfactant retention in chemical flooding

Surfactant retentions observed in four microemulsion-flooding pilot tests at the Loudon field were substantially lower than predicted from conventional laboratory coreflood experiments. This paper presents research results that explain this discrepancy. The oil reservoir was in an anaerobic, reducing conditions, whereas laboratory corefloods were normally conducted under aerobic, oxidizing conditions. The difference in redox condition was shown to have a serious effect on surfactant retention. Laboratory corefloods conducted under reservoir-like, anaerobic, reducing conditions gave surfactant retention results significantly closer to those observed in field tests. The effect of redox conditions on surfactant adsorption was substantiated further by results from static adsorption experiments with various clay types. Exposure of preserved cores from a reduced reservoir to aerobic conditions can cause high surfactant retention in corefloods. Methods were developed to restore such oxygen-contaminated core material to its original, anaerobic, reduced state. These coreflood procedures simulate actual reservoir conditions better and give meaningful surfactant-retention results for process design optimization.
The treatment of advanced or recurrent malignant genitourinary tumors in children

Wilms' tumor, embryonal rhabdomyosarcoma, and yolk sac tumor are the most frequently diagnosed malignant genitourinary tumors in children. The randomized therapeutic trials developed by the National Wilms' Tumor Study (NWTS) committee have produced significant improvements in the survival of Wilms' tumor patients. Those with Stage IV, favorable histology Wilms' tumor now have a 2-year survival rate of 87% to 93%. Patients with recurrent Wilms' tumor are being prospectively treated with new drugs and drug combinations with the goal of identifying active agents for inclusion in future therapeutic trials. Girls with localized embryonal rhabdomyosarcoma of the vagina have a 100% survival rate after treatment on the Intergroup Rhabdomyosarcoma Study (IRS) (IRS-1 or IRS-2). Primary treatment of patients with tumors of the prostate, bladder neck, or trigone with chemotherapy has demonstrated the need to establish local tumor control using surgery or radiation soon after diagnosis. The IRS-III currently is evaluating new drug combinations in this group of patients with locally advanced tumors. Patients with advanced yolk sac tumor have been treated using platinum-containing combination chemotherapy regimens with very encouraging results. Future research will evaluate the timing of second-look surgical procedures and the efficacy of etoposide-containing combination chemotherapy regimens.
New Electrochemical Methods for the Evaluation of Localized Corrosion in Engine Coolants

Due to the need of increasing energy efficiency, reducing pollution and lessening dependency on petroleum, vehicles using more advanced propulsion technologies such as fuel cell and hybrid electric (e.g., gasoline-electric or diesel-electric hybrid) power are being developed constantly. At the same time, extensive development efforts are being devoted to research aiming to increase the use of lighter metals such as magnesium alloys in today's engines. New engine coolants are often required to meet many of these new developments and the associated changes in cooling system requirements. Since corrosion protection is one of the key performance parameters for engine coolants, new and more effective corrosion measurement methods are useful for evaluating old and developing new coolants to meet the needs of new cooling systems or having improved corrosion protection performance, or both. Particularly, new electrochemical methods capable of more reliable, quantitative, and fast (ideally, real-time) measurements of localized corrosion such as pitting, crevice, and under-deposit corrosion, and corrosion under heat rejecting conditions are highly desired. Existing ASTM test methods for engine coolants either rely on inspection of the sample after a relatively long exposure period to determine the extent of localized attack or do not yield results directly related to localized corrosion. In this paper, coupled multi-electrode sensors test and simulated localized corrosion cell technique are compared and discussed to gain new insight for facilitating the development of more effective inhibited coolants.
The EAL Domain Protein VieA Is a Cyclic Diguanylate Phosphodiesterase

The newly recognized bacterial second messenger 3′,5′-cyclic diguanylic acid (cyclic diguanylate (c-di-GMP)) has been shown to regulate a wide variety of bacterial behaviors and traits. Biosynthesis and degradation of c-di-GMP have been attributed to the GGDEF and EAL protein domains, respectively, based primarily on genetic evidence. Whereas the GGDEF domain was demonstrated to possess diguanylate cyclase activity in vitro, the EAL domain has not been tested directly for c-di-GMP phosphodiesterase activity. This study describes the analysis of c-di-GMP hydrolysis by an EAL domain protein in a purified system. The Vibrio cholerae EAL domain protein VieA has been shown to inversely regulate biofilm-specific genes (vps) and virulence genes (ctxA), presumably by decreasing the cellular pool of c-di-GMP. VieA was maximally active at neutral pH, physiological ionic strength, and ambient temperatures and demonstrated c-di-GMP hydrolytic activity with a Km of 0.06 μm. VieA was unable to hydrolyze cGMP. The putative metal coordination site of the EAL domain, Glu170, was demonstrated to be necessary for VieA activity. Furthermore, the divalent cations Mg2+ and Mn2+ were necessary for VieA activity; conversely, Ca2+ and Zn2+ were potent inhibitors of the VieA phosphodiesterase. Calcium inhibition of the VieA EAL domain provides a potential mechanism for regulation of c-di-GMP degradation.
The Report of the National Commission to Study the Question of National Unity in Burundi: a Critical Comment

In May 1989 the National Commission for the Study of National Unity appointed by President Pierre Buyoya issued its eagerly awaited report, ostensibly designed to find a lasting solution to the bloody confrontations that have repeatedly pitted Hutu against Tutsi. For the first time in the history of independent Burundi an official statement has been made public which explicitly recognises the centrality of the Hutu-Tutsi problem, and sets forth specific solutions to resolve it. As such this is a document of historic significance, and the sum of its recommendations must be seen as an important breakthrough towards national reconciliation.
Evanescent-wave cavity ring-down spectroscopy: a new platform for thin-film chemical sensors

A new optical technique is described that permits extension of cavity ring-down spectroscopy (CRDS) to surfaces, films, and liquids. As in conventional CRDS, the photon intensity decay time in a low loss optical cavity is utilized to probe optical absorption. Extension to condensed matter is achieved by employing intra-cavity total internal reflection (TIR) to generate an evanescent wave that is especially well suited for thin film chemical sensing. Tow general monolithic cavity designs are discussed: (1) a broadband, TIR-ring cavity that employs photon tunneling to excite and monitor cavity modes, and (2) a narrow bandwidth cavity that utilizes a combination of TIR and highly reflective coatings. Following a qualitative description of design features, a beam transfer matrix analysis is given which yields stability criteria and mode properties as a function of cavity length and mirror radius of curvature. A signal- to-noise ratio calculation is given to demonstrate the evaluation of sensitivity.
Surgery of Right‐Sided Endocarditis: Valve Preservation Versus Replacement

Surgical treatment of right-sided endocarditis has in the past been centered on valve resection or resection with valve replacement. From 1981 to 1989, we attempted tricuspid valve repair in 19 patients with right-sided endocarditis. Fourteen of these were successful. The methods of valve repair and classification of the lesions that allow evaluation for repair are discussed, including the use of transesophageal echo and a hand-held color Doppler unit for intraoperative assessment.
A digital flux injector for NMR magnets

By periodically injecting a quantified amount of flux in a "slightly" resistive NMR magnet, a digital flux injector (DFI) enables the magnet to effectively operate in persistent mode. This paper presents: 1) parameters of the first full-scale DFI, specifically designed and built to operate with an LTS/HTS NMR magnet; and 2) its preliminary results when coupled to an LTS insert magnet in a bath of liquid helium.
"Marxism in Contemporary Western Archaeology", Bruce G. Trigger in Archaeological Method and Theory, Volume 5, edited by Michael B . Schiffer. Tucson, Unversity of Arizona Press 1993

Professor Trigger's contribution to Schiffer's volune is a well-reasoned and significant consideration of the influence of Marxist thought on the work of number of contemporary archaeologists. He is more critical of recent developments within Marxist archaeol­ogy than is McGuire; the article stands as a challenge to those who utilize Marxist ideas to reconsider the direction they have lately taken. In this article Trigger demonstrates his thorough knowledge of both Marxist theory and the social history of archaeology (here I am following Trigger's convention by capitalizing "Marxist"). Although his consideration of the contributions of Marxists to Western archaeology is generally sympathetic. he is unafraid to criticize where he feels it is appropriate. Like McGuire, Trigger offers critical insight on the relationship between Marxist philosophy and archaeology; unlike McGuire, Trigger explicitly limits his discussion to Western Europe and North America.
Correlates of patient satisfaction with physician visit: differences between elderly and non-elderly survey respondents.

Few studies document differences in patient satisfaction with physicians in the elderly (≥ 65 years) and compare it to non-elderly (<65 years) patients. A cross-sectional survey study on a convenience sample of 20,901 patients rated their recent visit to a physician through a web-based survey. Survey included validated questions based on aspects of physician care practice such as "friendliness", wait times and time spent with doctor. These scales were then used to measure patient satisfaction with physician. Statistical analysis involved pair-matching of non-elderly patients with elderly patients (both cohorts, n = 507 each) using propensity scores. Even though elderly and non-elderly patients had similar waiting times, elderly patients gave higher physician satisfaction scores than non-elderly patients (all p < 0.05). When predictors of physician satisfaction ratings were examined, shorter waiting time was more significantly associated with better treatment satisfaction in non-elderly patients (partial rho = -0.25 in the non-elderly compared to partial rho = -0.11 in elderly, p < 0.05). Increased time spent with the physician was more significantly correlated with higher physician satisfaction ratings in the non-elderly patients (partial rho = 0.38 in the non-elderly compared to partial rho = 0.18, p < 0.001). Increased patient satisfaction ratings of the non-elderly were associated more strongly with shorter waiting times than in the elderly. However overall, elderly patients reported similar waiting times and better physician satisfaction scores. Similarly, higher physician satisfaction in non-elderly patients were more strongly associated with increased time spent with physician than in the elderly patients.
Supersymmetry reach of an upgraded Fermilab Tevatron collider

We examine the capability of a {radical}{ital s} =2 TeV Fermilab Tevatron {ital p{bar p}} collider to discover supersymmetry, given a luminosity upgrade to amass 25 fb{sup {minus}1} of data. We compare with the corresponding reach of the Tevatron main injector (1 fb{sup {minus}1} of data). Working within the framework of minimal supergravity with gauge coupling unification and radiative electroweak symmetry breaking, we first calculate the regions of parameter space accessible via the clean trilepton signal from {ital {tilde W}}{sub 1}{ital {tilde Z}}{sub 2}{r_arrow}3{ital l}+{ital @};sE{sub {ital T}} production, with detailed event generation of both signal and major physics backgrounds. The trilepton signal can allow equivalent gluino masses of up to {ital m}{sub {ital {tilde g}}}{similar_to}600--700 GeV to be probed if {ital m}{sub 0} is small. If {ital m}{sub 0} is large, then {ital m}{sub {ital {tilde g}}}{similar_to}500 GeV can be probed for {mu}{lt}0; however, for {mu}{gt}0 and large values of {ital m}{sub 0}, the rate for {ital {tilde Z}}{sub 2}{r_arrow}{ital {tilde Z}}{sub 1}{ital l{bar l}} is suppressed by interference effects, and there is {ital no} reach in this channel. We also examine regions where the signal from {ital {tilde W}}{sub 1}{ital {tilde W}}{bar @}d1{r_arrow}{ital l{bar l}}+{ital @};sE{sub {ital T}}more » is detectable. Although this signal is background limited, it is observable in some regions where the clean trilepton signal is too small. Finally, the signal {ital {tilde W}}{sub 1}{ital {tilde Z}}{sub 2}{r_arrow}jets+{ital l{bar l}}+{ital @};sE{sub {ital T}} can confirm the clean trilepton signal in a substantial subset of the parameter space where the trilepton signal can be seen.« less
Teacher Knowledge of Educational Technology: A Case Study of Student/Mentor Teacher Pairs

This study had two purposes. The first was to explore the construct of teacher knowledge of educational technology through the lens of three components of Shulman's model of teachers' knowledge—con...
OEG implantation and step training enhance hindlimb-stepping ability in adult spinal transected rats

Numerous treatment strategies for spinal cord injury seek to maximize recovery of function and two strategies that show substantial promise are olfactory bulb-derived olfactory ensheathing glia (OEG) transplantation and treadmill step training. In this study we re-examined the issue of the effectiveness of OEG implantation but used objective, quantitative measures of motor performance to test if there is a complementary effect of long-term step training and olfactory bulb-derived OEG implantation. We studied complete mid-thoracic spinal cord transected adult female rats and compared four experimental groups: media-untrained, media-trained, OEG-untrained and OEG-trained. To assess the extent of hindlimb locomotor recovery at 4 and 7 months post-transection we used three quantitative measures of stepping ability: plantar stepping performance until failure, joint movement shape and movement frequency compared to sham controls. OEG transplantation alone significantly increased the number of plantar steps performed at 7 months post-transection, while training alone had no effect at either time point. Only OEG-injected rats plantar placed their hindpaws for more than two steps by the 7-month endpoint of the study. OEG transplantation combined with training resulted in the highest percentage of spinal rats per group that plantar stepped, and was the only group to significantly improve its stepping abilities between the 4- and 7-month evaluations. Additionally, OEG transplantation promoted tissue sparing at the transection site, regeneration of noradrenergic axons and serotonergic axons spanning the injury site. Interestingly, the caudal stump of media- and OEG-injected rats contained a similar density of serotonergic axons and occasional serotonin-labelled interneurons. These data demonstrate that olfactory bulb-derived OEG transplantation improves hindlimb stepping in paraplegic rats and further suggest that task-specific training may enhance this OEG effect.
Temperature distributions in the human leg for VLF-VHF exposures at the ANSI-recommended safety levels

Using a block model of 1532 cubical cells, temperature distributions are calculated for the lowest 21 cm of the human leg for electric fields recommended in the ANSI RF safety guideline. The thermal model uses inhomogeneous volume-averaged tissue properties: blood-flow rate, metabolism, thermal conductivity, specific heat, etc. The SARs are obtained using the impedance method. A modified finite-difference technique is used to solve the 3-D heat-conduction equation for the thermal model. Numerical results are obtained for RF currents at 3 and 40 MHz projected for the E fields recommended by the ANSI Standard (614 and 61.4 V/m, respectively) and also for power densities one-tenth of that level. Temperatures as high as 41.6 degrees C are obtained for some internal cells for the higher E fields while relatively moderate temperatures on the order of 37 degrees C are obtained for the lower E fields. Some of the calculated results for the surface temperature have been compared and found to be in good agreement with the experimental data for initial rates of heating. >
A video Time Encoding Machine

Time encoding is a real-time asynchronous mechanism of mapping analog amplitude information into multidimensional time sequences. We investigate the exact representation of analog video streams with a Time Encoding Machine realized with a population of spiking neurons. We also provide an algorithm that perfectly recovers streaming video from the spike trains of the neural population. Finally, we analyze the quality of recovery of a space-time separable video stream encoded with a population of integrate-and-fire neurons and demonstrate that the quality of recovery increases as a function of the population size.
Global Trends and School-Based Social Work

In the 21st century, substantial advancements have been made across the globe that positively affect the ability for school-based social workers in the fields of practice, policy, and research to meet the needs of the world’s youths. Nonetheless, children continue to suffer from poverty-stricken environments, absence of basic needs, poor or no health care, and insufficient access to quality education. The purpose of this article was to review recent trends in children’s rightsto education, psychological and behavioralhealth, and physiological health and to provide social workers with a contextual landscape for progress. Specific suggestions about how school-based social workers can make improvements across the globe are offered.
An Analysis of Memetic Crossover&#8217;s Impact on a Population

In problem domains such as robotic control, where the evaluation of an individual significantly dominates the rest of the evolutionary process with respect to time, the viability of an evolutionary approach can be called into question. In an effort to minimize the number of evaluations by maximizing the learning that takes place during an evaluation, a new crossover operator for genetic programming, memetic crossover, was recently introduced. This work analyzes the genealogical impact of this operator at varying levels. Although diversity, both in terms of individuals and nodes, is reduced in memetic crossover, we show that memetic crossover is capable of working with standard crossover to consistently improve the fitness of individuals.
Loyalty and Acquiescence: Authoritarian Regimes and Inequality Outcomes

This article seeks to explain inequality outcomes in authoritarian regimes as a function of the dierent combinations of loyalty-building and repressive measures (carrots and sticks) that authoritarian rulers use to maintain power. Like democratically-elected rulers, authoritarian rulers supply public and private goods in response to competitive pressures, and they can also employ repression to raise the costs of political dissent. The optimal combination of carrots and sticks varies across authoritarian regimes according to the nature of the political institutions by which authoritarian rule is organized. The results are economic policy outcomes that, over time, aect the level of economic inequality. Using a cross-national dataset covering over 80 authoritarian regimes observed during the 1965-2005 time period, this article develops and tests hypotheses that link inequality outcomes to authoritarian regime types.
Activity of the streptogramin antibiotic etamycin against methicillin-resistant Staphylococcus aureus

The alarming rise of hospital- and community-associated methicillin-resistant Staphylococcus aureus (HA- and CA-MRSA) infections has prompted a desperate search for novel antibiotics. We discovered the streptogramin etamycin produced by an actinomycete species isolated from the coast of Fiji, the first time this antibiotic has been identified from a marine microbe. Etamycin was extracted and purified from this strain (CNS-575) and identified as a three-rotamer species by 2D NMR spectroscopy. Etamycin demonstrated potent activity against HA- and CA-MRSA in microbroth dilution assays, with minimum inhibitory concentrations (MIC) as low as 1-2 mg l(-1) against HA- and CA-MRSA strains. Furthermore, etamycin was also active against other Gram-positive and several Gram-negative pathogens and was found to be non-cytotoxic at concentrations more than 20-fold above MIC. Etamycin displayed favorable time-kill kinetics compared with the first-line MRSA antibiotic, vancomycin, and also conferred significant protection from mortality in a murine model of systemic lethal MRSA infection. These data emphasize the utility of the marine environment as a relatively untapped source of antibiotics against major drug-resistant human pathogens. These studies will also guide future isolation and preclinical development of depsipeptide anti-MRSA compounds from marine-derived actinomycetes.
Resolving the components of transient signals using neural network and subspace inhibition filter algorithms

The authors compare the use of a multilayer perceptron neural network with the use of a subspace inhibition filter algorithm for achieving enhanced local resolution of the arrival times and frequencies of the components of a transient signal. Both the neural network algorithm and the subspace inhibition filter algorithm provide enhanced local resolution of the arrival times and frequencies of the components of a transient signal. Both algorithms allow for detection of signal components in the subregions in the presence of interference from neighboring regions. Both algorithms allow for this detection without the restriction that signals be centered on the Gabor lattice. For comparison, a binary classification example has been constructed in which there is no prior knowledge that one transient signal in noise is present in the subregion. Probability of false alarm and probability of detection are computed for a series of test signals presented to both detectors. It is shown that the neural network is comparable in performance to the subspace inhibition filter algorithm. >
Exploring the evolution of environmental sex determination, especially in reptiles.

Environmental sex determination has been documented in a variety of organisms for many decades and the adaptive significance of this unusual sexdetermining mechanism has been clarified empirically in most cases. In contrast, temperature-dependent sex determination (TSD) in amniote vertebrates, first noted 40 years ago in a lizard, has defied a general satisfactory evolutionary explanation despite considerable research effort. After briefly reviewing relevant theory and prior empirical work, we draw attention to recent comparative analyses that illuminate the evolutionary history of TSD in amniote vertebrates and point to clear avenues for future research on this challenging topic. To that end, we then highlight the latest empirical findings in lizards and turtles, as well as promising experimental results from a model organism, that portend an exciting future of progress in finally elucidating the evolutionary cause(s) and significance of TSD.
Looking ahead to Voyager 2

Voyager 2 will whiz past Saturn late next month, giving scientists yet another look at the planet's intricate ring system, its satellites, and the atmosphere. The encounter will concentrate on selected targets, though, rather than take a sweeping look at the entire Saturnian system, as Voyager 1 did. Voyager 2 will take higher-resolution photographs of five satellites—Enceladas, Tethys, lapetus, Hyperion, and Phoebe—than did its sister ship. Higher-resolution pictures of the rings also are expected. Closest approach to the planet will be on August 25 at 8:25 P.M. PDT (11:25 P.M. EDT). Transmission of signals from the spacecraft to earth will take nearly another hour and a half.
Congenital esotropia and the risk of mental illness by early adulthood.

Objective The purpose of this study is to investigate whether children with congenital esotropia (CET) are more likely than controls to develop mental illness by early adulthood. Design Retrospective, population-based cohort. Participants Children (aged Methods The medical records of patients with esotropia and their controls were retrospectively reviewed for the subsequent development of psychiatric disease. Main Outcome Measures The development of mental illness and associated comorbidities among patients with CET and their controls. Results A mental health disorder was diagnosed in 42 (33%) of the 127 patients with CET followed to a mean age of 20.4 years compared with 16% of controls ( P = 0.002). Congenital esotropia increased the odds of developing a psychiatric illness 2.6 times (confidence interval, 1.5–4.8) compared with controls. The number of mental health diagnoses ( P = 0.019) and the use of psychotropic medications ( P = 0.015) were significantly more common among esotropic patients compared with non-strabismic controls. Conclusions Congenital esotropia, similar to those with intermittent exotropia or convergence insufficiency, increases the odds of developing mental illness by early adulthood 2.6 times compared with controls. The cause of this association does not seem to be associated with premature birth. Financial Disclosure(s) The author(s) have no proprietary or commercial interest in any materials discussed in this article.
β-Adrenergic Antagonists in Hypertension: A Review of the Evidence

Objective:To evaluate the effects of β-adrenergic antagonist therapy on cardiovascular and cerebrovascular outcomes in the treatment of hypertension.Data Sources:Literature searches were conducted using MEDLINE (1966–August 2009), International Pharmaceutical Abstracts (1970–August 2009), and Cochrane Database of Systematic Reviews (until third quarter 2009) to locate clinical trials and meta-analyses comparing β-blocker therapy with placebo or other antihypertensive agents in patients with hypertension. Bibliographies from relevant research and review articles were reviewed for additional references.Study Selection and Data Extraction:All English-language articles identified from the data sources were reviewed. Articles describing original research with cardiovascular or cerebrovascular outcomes and/or death as either primary or secondary endpoints were included. Articles describing the use of β-blocker therapy for conditions other than hypertension were not included,Data Synthesis:Five placebo-controlle...
Tribal diversity, human resources management practices, and firm performance

This study explores the relationship between tribal diversity, human resources management practices, and firm performance in Africa. Using multiple data sources and multilevel techniques, I examine tribal diversity as a driver of human resource management-diversity policy (HRM-DP) and an interactive factor influencing firm performance. Tribal identity is also tested as a determinant of tribal diversity. The results show that HRM-DP mediates the relationship between tribal diversity and firm performance. Tribal identity also relates negatively to tribal diversity, HRM-DP, and firm performance. Lastly, tribal diversity interacts with tribal identity in relating to firm performance. Theoretical and practical implications are discussed to enhance tribal diversity management in Africa. Copyright © 2016 ASAC. Published by John Wiley & Sons, Ltd. Resume Cette etude explore la relation entre la diversite tribale, les pratiques de gestion en ressources humaines et la performance des entreprises en Afrique. A partir des sources de donnees multiples et des techniques multiniveaux, elle considere la diversite tribale comme un vecteur de la dyade gestion des ressources humaines - politique en matiere de diversite (HRM-DP) et comme un facteur interactif influencant la performance des entreprises. Elle teste aussi l'identite tribale en tant que determinant de la diversite tribale. Les resultats montrent que la dyade HRM-DP mediatise la relation entre la diversite tribale et la performance des entreprises. L'identite tribale est aussi negativement reliee a la diversite tribale, au HRM-DP et a la performance des entreprises. Enfin, la diversite tribale interagit avec l'identite tribale pour influencer la performance des entreprises. L'article s'acheve par une analyse des implications theoriques et pratiques destinees a rehausser la gestion de la diversite tribale en Afrique. Copyright © 2016 ASAC. Published by John Wiley & Sons, Ltd.
Student and Instructor Use of the Teacher Behavior Checklist

Despite the demonstrated reliability and validity of the Teacher Behavior Checklist (TBC) as a tool for evaluating postsecondary instructors, research has yet to consider the impact of student, ins...
Baptist Preachers and the New Deal

When Franklin D. Roosevelt was inaugurated president on 4 March 1933, the United States was in the deepest economic depression in its history, a crisis which brought the political and economic system to the edge of breakdown and threatened so cial chaos. Worsening conditions had forced numerous banks to close before the new president and Congress ordered a banking "holiday." The stock market was at low ebb. Industrial produc tion was down to 56 percent from the 1923-25 level. Out of a labor force of 52 million, one wage earner in four did not have a job to support himself or his family. Another 5.5 million labor ers were only partially employed. In farming areas conditions were hardly better. Unable to sell corn for a profit, midwestern farmers burned the previous year's crop to keep away the win ter's cold. Essentially no markets existed for such southern cash crops as cotton, tobacco, and peanuts.1 Under such conditions, at President Roosevelt's initiative, Congress passed dozens of major bills and hundreds of lesser ones to attack the problems the Great Depression had created. Compared to the previous Herbert Hoover administration, the
Vinylnitrene formation from 3,5-diphenyl-isoxazole and 3-benzoyl-2-phenylazirine.

Photolysis of 1 in argon-saturated acetonitrile yields 2, whereas in oxygen-saturated acetonitrile small amounts of benzoic acid and benzamide are formed in addition to 2. Similarly, photolysis of 2 in argon-saturated acetonitrile results in 1 and a trace amount of 3, whereas in oxygen-saturated acetonitrile the major product is 1 in addition to the formation of small amounts of benzoic acid and benzamide. Laser flash photolysis of 1 results in an absorption due to triplet vinylnitrene 4 (broad absorption with λmax at 360 nm, τ = 1.8 μs, acetonitrile) that is formed with a rate constant of 1.2 × 107 s–1 and decays with a rate constant of 5.6 × 105 s–1. Laser flash photolysis of 2 in argon-saturated acetonitrile likewise results in the formation of triplet vinylnitrene 4 but also ylide 5 (λmax at 440 nm, τ = 13 μs). The rate constant for forming 4 in argon-saturated acetonitrile is 1.6 × 107 s–1. In oxygen-saturated acetonitrile, vinylnitrene 4 reacts to form the peroxide radical 6 (λmax 360 nm, ∼0.7 μs, a...
Toward development of an autonomous network of bacteria-based delivery systems (BacteriaBots): spatiotemporally high-throughput characterization of bacterial quorum-sensing response.

Characterization of bacterial innate and engineered cooperative behavior, regulated through chemical signaling in a process known as quorum sensing, is critical to development of a myriad of bacteria-enabled systems including biohybrid drug delivery systems and biohybrid mobile sensor networks. Here, we demonstrate, for the first time, that microfluidic diffusive mixers can be used for spatiotemporally high-throughput characterization of bacterial quorum-sensing response. Using this batch characterization method, the quorum-sensing response in Escherichia coli MG1655, transformed with a truncated lux operon from Vibrio fischeri, in the presence of 1–100 nM exogenous acyl-homoserine lactone molecules has been quantified. This method provides a rapid and facile tool for high-throughput characterization of the quorum-sensing response of genetically modified bacteria in the presence of a wide concentration range of signaling molecules with a precision of ±0.5 nM. Furthermore, the quorum-sensing response of Ba...
Influence of Cattle Anterior Pituitary Extract on Endochondral Ossification in Young Ovariectomized Guinea Pigs.

SummaryIn growing guinea pigs, ovariectomy causes hyperplasia and hypertrophy of the epiphyseal cartilage, whereas its calcification and ossification are not accelerated in the same ratio. Consequently, the closure of the epiphyseal line is delayed, and a relative increase in the size of the individual bone may occur. Whether these changes may lead to gigantism-like, permanent conditions or whether they are only of a temporary nature, which may become compensated at a later stage, is not as yet decided. The above effect of ovariectomy is interfered with by the interaction of acid extract of cattle anterior pituitary, which has the tendency to exert its specific growth-promoting and calcifying influence on the cartilage. If the two factors act simultaneously, a competition between both principles takes place and a combination effect results, the outcome of which determines the course of the endochondral ossification.
Frost/Nixon: directed by Ron Howard, with screenplay by Peter Morgan. Universal City, CA: Universal Pictures, Imagine Entertainment, and Working Title Films, 2008

Frost/Nixon follows the events that occurred prior to and directly after the famous Frost/Nixon interviews of 1977. Richard Nixon is portrayed by Frank Langella and David Frost is portrayed by Mich...
The significance of lymphoid follicles in the interpretation of gastric biopsy specimens

Lymphoid follicles are a common feature of Helicobacter pylori-associated gastritis. Recently, by using gastric mapping, we demonstrated lymphoid follicles in all of 62 patients with H pylori infection. This study was designed to address (1) the prevalence of lymphoid follicles in routine gastric biopsy specimens, (2) their correlation with chronic active gastritis, and (3) their predictive value with respect to H pylori infection. Slides from 174 patients whose gastric biopsy findings carried a nonneoplastic diagnosis were evaluated for the presence of (1) chronic active gastritis, (2) lymphoid follicles, and (3) H pylori. When either follicles or active gastritis was found, but H pylori could not be identified by the hematoxylin-eosin stain, additional slides were prepared with a newly developed silver-hematoxylin-eosin-alcian blue stain. Active gastritis was present in 153 patients (88%). Helicobacter pylori was identified on hematoxylin-eosin-stained slides in 123 patients and by the modified Steiner stain in 11 additional patients. Thus, 87% of the patients with chronic active gastritis had histologically detectable H pylori infection. One or more lymphoid aggregates were present in 110 patients (82% of patients with H pylori and 72% of those with chronic active gastritis). Of these, 101 (92%) had H pylori infection. In six of the nine H pylori-negative patients with lymphoid aggregates, biopsy specimens were taken from the edges of an ulcer. In summary, except when biopsy specimens are obtained from the immediate vicinity of a gastric ulcer, lymphoid aggregates in a gastric biopsy specimen are virtually always associated with chronic active gastritis and provide a useful marker for H pylori infection.
Modified Blalock-Taussig shunt following long-term administration of prostaglandin E1 for ductus-dependent neonates with cyanotic congenital heart disease.

In the treatment of cyanotic heart diseases in neonates who are ductus dependent, the small size of the pulmonary artery and/or subclavian artery often precludes construction of a sufficient Blalock-Taussig shunt. To avoid an emergency operation and to obtain pulmonary and subclavian arteries of adequate size (3 mm), a low dose of prostaglandin E1 was given to 16 neonates for a mean of 47 days (range 26 to 65 days), and a modified Blalock-Taussig shunt operation was performed in neonates whose mean age was 50 days. The pulmonary artery grew significantly (mean 4.5 mm) and the mean diameter of the subclavian artery was 3 mm, which was large enough for a good shunt at the time of operation. There were two late deaths and one operative death. All surviving patients had patent shunts at the mean follow-up period of 22 months. The shunt was constructed on the same side as the ductus arteriosus so that the ductus could be ligated at the same operation in selected cases; the ductus may not close after discontinuation of prostaglandin E1 infusion and may cause uncontrollable congestive heart failure because of excessive pulmonary blood flow, particularly in patients with a univentricular heart. The ductus, dissected in nine patients, was enlarged and elongated in all and was ligated in four patients without complication.
Single-Molecule Measurements of Topoisomerase Activity with Magnetic Tweezers

Magnetic tweezers provide a versatile tool enabling the precise application of force and torque on -individual biomolecules. These properties make magnetic tweezers uniquely suited for the study of DNA topology and topoisomerases at the single-molecule level. Single-molecule approaches, which are complementary to ensemble biochemical and structural approaches, have provided remarkable insights into the mechanisms of topoisomerase activity and interactions with DNA. Here, we describe how to make single-molecule measurements of topoisomerase activity with a magnetic tweezers instrument. We provide detailed instructions for preparing and characterizing DNA substrates, flow cells, and supercoilable DNA tethers. We then describe magnetic tweezers measurements of supercoil relaxation by single topoisomerases.
Nitrate uptake varies with tide height and nutrient availability in the intertidal seaweed Fucus vesiculosus.

Intertidal seaweeds must cope with a suite of stressors imposed by aerial exposure at low tide, including nutrient limitation due to emersion. Seaweeds can access nutrients only when submerged, so individuals living higher compared to lower on the shore may have adaptations allowing them to acquire sufficient amounts of nutrients to survive and maintain growth. Using a combination of observations and experiments, we aimed to identify intraspecific variation in nitrate uptake rates across the intertidal distribution of F. vesiculosus, as well as test for acclimation in response to a change in tide height. We replicated our study at sites spanning nearly the entire Gulf of Maine coastline, to examine how local environmental variability may alter intraspecific variation in nitrate uptake. We found that average nitrate uptake rates were ~18% higher in upper compared to lower intertidal Fucus vesiculosus. Furthermore, we found evidence for both acclimation and adaptation to tide height during a transplant experiment. F. vesiculosus transplanted from the lower to the upper intertidal zone was characterized by increased nitrate uptake, but individuals transplanted from the upper to the lower intertidal zone retained high uptake rates. Our observations differed among Gulf of Maine regions and among time points of our study. Importantly, these differences may reflect associations between nitrate uptake rates and abiotic environmental conditions and seaweed nutrient status. Our study highlights the importance of long-term variation in ambient nutrient supply in driving intraspecific variation of seaweeds across the intertidal gradient and local and seasonal variation in ambient nutrient levels in mediating intraspecific differences.
Robotics for Education

Educational robotics programs have become popular in most developed countries and are becoming more and more prevalent in the developing world as well. Robotics is used to teach problem solving, programming, design, physics, math and even music and art to students at all levels of their education. This chapter provides an overview of some of the major robotics programs along with the robot platforms and the programming environments commonly used. Like robot systems used in research, there is a constant development and upgrade of hardware and software – so this chapter provides a snapshot of the technologies being used at this time. The chapter concludes with a review of the assessment strategies that can be used to determine if a particular robotics program is benefitting students in the intended ways.
Prior Autologous Hematopoietic Cell Transplantation Confers an Adverse Prognosis for Recipients of Allogeneic Transplantation Following Nonmyeloablative Preparative Conditioning.

Allogeneic hematopoietic transplantation following nonmyeloablative preparative conditioning (also know as “mini-dose transplantation”) is frequently applied to patients who, on the basis of prior therapy, organ dysfunction, or co-morbid conditions may be considered ineligible for full, dose-intenstive treatment. This approach assumes that early regimen-related toxicity can be averted by the nonmyeloablative approach. We present the results obtained in a group of consecutive, unselected older adults with advanced hematologic neoplasia who underwent allogeneic transplantation from fully histocompatible siblings or unrelated donors after dose-reduced preparative conditioning in a single center. Thirty-four patients, median age 57 years (range 26–66) underwent allogeneic transplantation from siblings (14 patients) or unrelated donors (20 patients) following preparative conditioning consisting of chemotherapy only (typically fludarabine, cytarabine, and cyclophosphamide) or those drugs plus antithymocyte globulin, respectively. One recipient of a related allograft and one recipient of an unrelated allograft received preparative fludarabine/melphalan and busulfan/fludarabine/ATG, respectively. Diagnoses prior to transplantation included advanced acute leukemia and myelodysplasia (17 patients), nonHodgkin’s or Hodgkin’s lymphoma (11 patients), and CLL or Multiple Myeloma (6 patients). Allogeneic transplantation followed previous autologous transplantation in 17 patients. Time from previous autologous transplantation to nonmyeloablative allogeneic transplantation varied. Prior autograft conferred a significant adverse risk on recipients of allogeneic transplants following nonmyeloablative conditioning. Only two of 17 patients with a history of prior autograft enjoyed long-term survival as opposed to seven of 17 who had not undergone prior autologous transplant. Mortality before day + 100, typically attributed to treatment-related toxicities, occurred in 11 patients; nine of these patients had had prior autologous transplantation. Prior autologous transplantation typically was done for acute myelogenous leukemia in first complete remission and referral for allotransplant may have been an indicator of more aggressive disease biology. In conclusion, allogeneic transplantation following a nonmyeloablative preparative regimen may be associated with significant risk of early mortality in patients who undergo this treatment after prior autologous transplantation, especially for acute leukemia, suggesting that criteria for allogeneic transplantation after nonmyeloablative condition should take this risk into account. Further studies from multiple centers will be required to confirm this observation.
Waking from the Dream: The Struggle for Civil Rights in the Shadow of Martin Luther King, Jr.: Chappell, David L. Durham: Duke University Press 266 pp., $23.95 ISBN 978-0-8223-6172-5 Publication Date: 2016

In her influential essay on the long civil rights movement published by the Journal of American History in 2005, Jacquelyn Dowd Hall called for more studies to be written on the black freedom strug...