cssi/SciSciGPT-SciSciNet huggingface dataset:
Assessment Question Characteristics Predict Medical Student Performance in General Pathology.

Context.— Evaluation of medical curricula includes appraisal of student assessments in order to encourage deeper learning approaches. General pathology is our institution's 4-week, first-year course covering universal disease concepts (inflammation, neoplasia, etc). Objective.— To compare types of assessment questions and determine which characteristics may predict student scores, degree of difficulty, and item discrimination. Design.— Item-level analysis was employed to categorize questions along the following variables: type (multiple choice question or matching answer), presence of clinical vignette (if so, whether simple or complex), presence of specimen image, information depth (simple recall or interpretation), knowledge density (first or second order), Bloom taxonomy level (1-3), and, for the final, subject familiarity (repeated concept and, if so, whether verbatim). Results.— Assessments comprised 3 quizzes and 1 final exam (total 125 questions), scored during a 3-year period (total 417 students) for a total 52 125 graded attempts. Overall, 44 890 attempts (86.1%) were correct. In multivariate analysis, question type emerged as the most significant predictor of student performance, degree of difficulty, and item discrimination, with multiple choice questions being significantly associated with lower mean scores (P = .004) and higher degree of difficulty (P = .02), but also, paradoxically, poorer discrimination (P = .002). The presence of a specimen image was significantly associated with better discrimination (P = .04), and questions requiring data interpretation (versus simple recall) were significantly associated with lower mean scores (P = .003) and a higher degree of difficulty (P = .046). Conclusions.— Assessments in medical education should comprise combinations of questions with various characteristics in order to encourage better student performance, but also obtain optimal degrees of difficulty and levels of item discrimination.
Quantum dot lasers—History and future prospects

We describe the initial efforts to use molecular beam epitaxy to grow InAs quantum dots on GaAs via the Stranski–Krastanov transition and then discuss the initial efforts to use these quantum dots to demonstrate quantum dot lasers. We discuss the developments in quantum dot lasers over the past 20 years and the future prospects for these lasers for scientific and commercial applications.
The Functional Independence Measure and the Functional Assessment Measure (FIM + FAM) as an effective tool for the evaluation of functional status in stroke rehabilitation: A review

The Functional Independence Measure and Functional Assessment Measure (FIM + FAM) is an effective, efficient, and objective tool for tracking changes in the motor, cognitive, and psychosocial functions of patients over the entire treatment and rehabilitation period. It is estimated that in the Czech Republic (CR), stroke is the third most common cause of death and the most common cause of adult disability. To develop faster, better, and more cost‑effective stroke treatments and reduce or mitigate functional losses and restrictive situations, it is very important that patients be objectively evaluated, relative to their functional abilities, as soon as possible after a stroke. A critical part of stroke treatment is to calculate the length of in‑hospital treatment and estimate the length of the rehabilitation period after the stroke. Contemporary methods for evaluating and analyzing a patient’s condition are based on test results and evidence.The FIM offers a more sensitive rating scale compared to BI due to the presence of cognitive items and is used worldwide for assessment during the acute stage of the disease. Thus, it is an efficient instrument for setting therapy goals and evaluating the effects of rehabilitation. Not only can it assist the therapist in clinical decision making, but it also functions as a tool for evaluating rehabilitation outcomes. Based on this test, short‑term and long‑term rehabilitation plans can be determined. At the end of the rehabilitation process, assessing the patient’s functional condition helps to predict the specific long‑term rehabilitation services the patient will need as they return to society and regain their quality of life.
A data-driven peridynamic continuum model for upscaling molecular dynamics.

Nonlocal models, including peridynamics, often use integral operators that embed lengthscales in their definition. However, the integrands in these operators are difficult to define from the data that are typically available for a given physical system, such as laboratory mechanical property tests. In contrast, molecular dynamics (MD) does not require these integrands, but it suffers from computational limitations in the length and time scales it can address. To combine the strengths of both methods and to obtain a coarse-grained, homogenized continuum model that efficiently and accurately captures materials' behavior, we propose a learning framework to extract, from MD data, an optimal Linear Peridynamic Solid (LPS) model as a surrogate for MD displacements. To maximize the accuracy of the learnt model we allow the peridynamic influence function to be partially negative, while preserving the well-posedness of the resulting model. To achieve this, we provide sufficient well-posedness conditions for discretized LPS models with sign-changing influence functions and develop a constrained optimization algorithm that minimizes the equation residual while enforcing such solvability conditions. This framework guarantees that the resulting model is mathematically well-posed, physically consistent, and that it generalizes well to settings that are different from the ones used during training. We illustrate the efficacy of the proposed approach with several numerical tests for single layer graphene. Our two-dimensional tests show the robustness of the proposed algorithm on validation data sets that include thermal noise, different domain shapes and external loadings, and discretizations substantially different from the ones used for training.
Impact of Electronic Procedural Protocoling on the Timeliness of Pre-operative Breast Localization Procedures.

Abstract Objective To evaluate the impact of a new electronic procedural protocol on start times of pre-operative breast localization procedures. Methods This HIPAA-compliant, Institutional Review Board-exempted, quality improvement initiative was performed at a large tertiary academic center. In May 2018, an electronic version of the pre-procedure protocol for breast localizations was created within the electronic health record; prior to this time, the protocol was completed manually on a paper form. Mean time between: (1) appointment time and procedure start time, (2) procedure begin-to-end time, and (3) arrival to appointment time were compared for all female patients undergoing pre-operative breast localization procedures during 4-month periods pre-implementation of the electronic procedural protocol (January-April 2018), and post-implementation (June-September 2018), excluding the May 2018 implementation month. Statistical analysis was done by two tailed t-test and statistical process control charting. Results Pre-implementation, 427 procedures were performed, and post-implementation 409 procedures were performed. Three pre-implementation cases performed more than 3 hours prior to appointment time were excluded (presumed to be rescheduled cases). Mean time between appointment time and procedure start time decreased from 2.7 minutes after to 5.6 minutes before appointment start time, an 8.3-minute improvement (P = 0.0001), with sustained improvement by statistical process control analysis. Mean time for procedure length increased by 4.7 minutes (P = 0.001). There was no significant difference in mean time of patient arrival to appointment time pre- and post-implementation. Conclusion Implementation of an electronic protocol process for pre-operative breast localizations was associated with a significant and sustained reduction in time between appointment time and procedure start time.
Aging, obesity, sarcopenia and the effect of diet and exercise intervention.

Abstract The number of adults 65 years and older is increasing worldwide and will represent the 20% of the population by 2030. Half of them will suffer from obesity. The decline in muscle mass and strength, known as sarcopenia, is very common among older adults with obesity (sarcopenic obesity). Sarcopenic obesity is strongly associated with frailty, cardiometabolic dysfunction, physical disability, and mortality. Increasing efforts have been hence made to identify effective strategies able to promote healthy aging and curb the obesity pandemic. Among these, lifestyle interventions consisting of diet and exercise protocols have been extensively explored. Importantly, diet-induced weight loss is associated with fat, muscle, and bone mass losses, and may further exacerbate age-related sarcopenia and frailty outcomes in older adults. Successful approaches to induce fat mass loss while preserving lean and bone mass are critical to reduce the aging- and obesity-related physical and metabolic complications and at the same time ameliorate frailty. In this review article, we discuss the most recent evidence on the age-related alterations in adipose tissue and muscle health and on the effect of calorie restriction and exercise approaches for older adults with obesity and sarcopenia, emphasizing the existing gaps in the literature that need further investigation.
Quantitative MRI Differences Between Early versus Late Onset Alzheimer's Disease.

Investigators report greater parietal tau deposition and alternate frontoparietal network involvement in early onset Alzheimer’s Disease (EOAD) with onset <65 years as compared with typical late on...
Ibuprofen Versus Indomethacin for Medical Closure of the Patent Arterial Duct: A Pooled Analysis by Route of Administration.

Introduction: Preterm infants are at increased risk of having a patent arterial duct (PAD). PADs may cause congestive heart failure, respiratory distress, necrotizing enterocolitis, and renal impairment. Consequently, in some infants, it becomes necessary to attempt closure of the PAD. Surgical closure can be difficult in small infants and is not without its risks; thus, medical closure offers advantages. Cyclooxygenase inhibitors have been used for medical closure of the PAD with both ibuprofen and indomethacin having been used clinically. Methods: We performed a systematic review of the literature to identify all studies comparing ibuprofen and indomethacin. Studies comparing ibuprofen and indomethacin for closure of the PAD in premature infants were included in the meta-analysis. A subanalysis was performed to compare the route of administration. Efficacy endpoints studied were PAD closure and surgical ligation while adverse effects studied were death in the first month of life, necrotizing enterocolitis, gastrointestinal bleeding, intestinal perforation, bronchopulmonary dysplasia in the first month of life, Grade 3 or 4 intraventricular hemorrhage, and change in the serum creatinine after treatment. Results: Ibuprofen and indomethacin were equally effective in closing the PAD in premature infants and demonstrated no difference in the incidence of adverse events. In respect to the route of administration, oral ibuprofen was as effective as intravenous indomethacin. When comparing both drugs via the intravenous route, the only difference noted between the ibuprofen and indomethacin was that ibuprofen was associated with a lesser increase in serum creatinine after treatment. Conclusion: Ibuprofen and indomethacin are equally effective in PAD closure without any difference in the incidence of adverse events. Importantly, oral ibuprofen was as effective as intravenous indomethacin.
Ports and Ladders: The Nature and Relevance of Internal Labor Markets in a Changing World

Excerpt] Many believe that the nature of careers has changed dramatically in the past twenty years. One scholar writes that internal labor markets have been 'demolished', while a human resources manager at Intel comments that, in contrast to the past, today, 'You own your own employability. You are responsible' (Knoke 2001: 31). The idea of the 'boundaryless career' seems increasingly popular (Arthur and Rousseau 1996). If it is in fact true that the old rules for organizing work have disappeared, this would represent a fundamental change for employees. It would also have major implications for how scholars think about the labor market. Not surprisingly, the reality is more complicated, with evidence of both change and stability in the nature of the employment relationship. In this chapter we discuss the nature of these developments and their implications for the internal labor market literature.
Cytotoxicity of etidronic acid to human breast cancer cells.

Methods: In vitro cytotoxicity of etidronic acid to MCF-7 cells was estimated on the basis of clonogenicity assays, while cell cycle effects were determined by using flow cytometry. Mutagenicity of etidronic acid was detected by using denaturing high-pressure liquid chromatography analysis of cellular DNA amplified by PCR with primers for exons 5 through 8 of the human p53 gene. Results: A 24-hour treatment with etidronic acid (10 mM) with or without strontium chloride was cytototoxic to MCF-7 cells. Etidronic acid caused a decrease in the S-phase population and an increase in the G2/M population. Mutations in the p53 gene were detected in MCF-7 cells treated with etidronic acid. Strontium chloride was not cytotoxic to cells. Conclusions: Cytotoxicity of etidronic acid to breast cancer cells may complement its inhibitory effects on bone resorption at the site of bone metastasis. Within the cell cycle, late S-phase cells are the most radioresistant, while cells at the G2/M border are the most sensitive. Therefore the decrease in S-phase population with corresponding increase in G2/M would make the cells more radiosensitive. This may be useful if etidronic acid were combined with radioactive strontium ( 89 Sr, metastron) or external-beam radiotherapy for treating bone metastases. Tumor cells that survive etidronic acid treatment may acquire drug resistance because of mutations in the p53 tumor-suppressor gene. (Ethn Dis. 2008;18[Suppl 2]:S2-87–S2-92)
Criminal (In)Justice and Democracy in America

This essay responds to Nicola Lacey’s review of my recent book The Machinery of Criminal Justice (Oxford Univ. Press 2012). Lacey entirely overlooks the book’s fundamental distinction between making criminal justice policy wholesale and adjudicating deserved punishment at the retail level, in individual cases, which is quite consistent with keeping but tempering rules. She also undervalues America’s deep commitments to federalism, localism, and democratic self-government and overlooks the related problem of agency costs in criminal justice. Her top-down approach colors her desire to pursue equality judicially, to the exclusion of the political branches. Finally, Lacey denigrates the legitimate roles of emotion and retribution in criminal justice. A consideration of the recent outcry over a gang-rape-murder in India highlights the shortcomings of her clinical, therapeutic, overly professionalized approach to criminal justice.
Tetra­ammonium benzene‐1,2,4,5‐tetra­carboxyl­ate tetrahydrate

The anions in the title compound, 4NH4+·C10H2O84−·4H2O, are held together by regular hydrogen bonds from the carboxyl­ate O atoms to the ammonium cations and water mol­ecules, forming a three-dimensional network.
Anesthesia for Endoscopy

Anesthesia for endoscopic surgery can be challenging depending on surgical manipulations and patient comorbidity. Anesthetists must understand the possible systemic changes and complications that are associated with endoscopic surgery. Pneumoperitoneum induces vasoconstriction, reduces cardiac output, and decreases functional residual capacity in the cardiopulmonary system. Both hypoventilation caused by the thoracoscopic procedure and CO2 insufflation increase Paco2. To prevent the problems associated with high Paco2, monitoring of end-tidal CO2 (ETco2) and capability of positive pressure ventilation are crucial. Sudden changes of ETco2 should be monitored closely. Endoscopic surgery should be a less invasive procedure; however, appropriate analgesia remains necessary.
Long-term follow-up and analysis for prognostic factors for patients with limited-stage diffuse large-cell lymphoma treated with initial chemotherapy with or without adjuvant radiotherapy.

In order to assess long-term outcome of patients with localized (stage I or II) diffuse large-cell lymphoma treated with initial combination chemotherapy with cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) with or without involved-field radiotherapy following chemotherapy, we combined data from two prospective trials in Tucson (64 patients) and Vancouver (78 patients). Follow-up on 142 patients was updated and a variety of potential pretreatment prognostic factors were analyzed for impact on outcome. One hundred forty patients (99%) achieved a complete remission and there were no differences in outcome between institutions. Twenty-three patients have relapsed and 22 have died from lymphoma at a median follow-up of 4.4 years, resulting in an overall relapse-free survival of 82% at 5 years. There was no treatment-related mortality and were no instances of late cardiac toxicity or leukemia. Of the following potential pretreatment prognostic factors (age, stage, "B" symptoms, extranodal dis...
Apolipoprotein E and functional motor severity in cerebral palsy.

Cerebral palsy is attributed to non-progressive disturbances in the developing fetal or infant brain. The APOE e4 allele has been associated with poor outcome after brain injury in adults but may be protective among very young children. We conducted this study to explore the hypothesis that the APOE e4 is associated with lowered severity of cerebral palsy. 158 individuals with CP and their parents were genotyped for APOE. Mean age was 9.1 years; 54% were males. 61% were preterm at birth; 34% less than 30 weeks gestation. 30% of the CP subjects had at least one e4 allele. There was a trend towards significance for subjects with at least one e4 allele assigned to the low severity group (p = 0.11). The greater number of e4 alleles, the more likely an individual was in the low severity CP group (p = 0.12). Individuals with brain injury in the perinatal period were almost 5 times more likely to be in the low severity group ( p< 0.01). Family analysis via the TDT supported a protective effect of APOE e4. Further study is needed to confirm that, in contrast to adults, the APOE e4 allele appears to confer protection and/or facilitate recovery after brain injury in the fetus or newborn, particularly when that injury occurs around term.
Monitoring and Controlling Criminal Offenders Using the Satellite Global Positioning System Coupled to Surgically Implanted Transponders: Is It a Viable Alternative to Prison?

This essay criticizes the continuing use of prisons as the primary means of controlling adjudicated criminal offenders. After conceding that prisons do control, but in ways which violate most of what has been discovered and should be known about how to promote lasting, positive behavior change, the argument is advanced that prisons are obsolete and should be replaced by a satellite surveillance system that would offer a better, less costly method to both monitor and control criminal offenders under conditions with far more potential for successful rehabilitation efforts.
Electron microscope studies of blood cells.

Several technics were employed for the application of the electron microscope to the study of the blood cells. First; lymphocytes, macrophages, and neutrophilic leukocytes of acute inflammatory lesions in man were prepared by imbedding formvar-covered screens in the corium of the forearm. Exudative cells which migrated to the undersurfaces of the specimen screens were quick-frozen and dehydrated in vacuo, according to a modified Altmann-Gersh technic. In some cases formvar-covered glass cover slips were substituted for the screens in the lesions, in which case an extra step was needed to transfer the preparations to specimen screens. In a further technic, blood cells of lymph nodes, spleen and bone marrow of man were imprinted upon glass slides covered with formvar. These preparations were also frozen and dehydrated in vacuo. The films were then transferred to screens by a direct method in which the cells were retained intact. Neutrophil granules, seen only as irregular, indistinct granules with the optical microscope, are actually round, oval, or rod-shaped structures measuring from 70 by 85 millimicrons up to as much as 465 by 650 millimicrons. Immature blood cell precursors were found to possess fine chromatin patterns with distinct chromatin-parachromatin distinction and well-demarcated nucleoli. At the higher magnifications made possible by electron microscopy, a new level of cytostructural organization appeared in the mononuclear phagocytes or macrophages. Individual fibrillar structural units can be made out in both the nuclear and cytoplasmic protoplasm which can be measured in Angstrom units. The nuclear protoplasmic interstices so formed are smaller than the corresponding cytoplasmic areas. The nuclear membrane is actually an anchoring structure for both nuclear and cytoplasmic fibrillar cross-pieces. Phagocytosis is depicted and the wall of the phagocytic vacuole is described. Finally, the observed cyto-structural features of the blood cells are discussed in the light of newer concepts of the finer structure of protoplasm.
Interaction between thermophilic microorganisms and crude oils: recent developments

Abstract A considerable research effort in the area of microbially enhanced oil recovery (MEOR) has shown that it is promising and that a recovery biotechnology may be developed. Successful biochemical processes would have to be cost effective and have certain attributes, such as being able to produce emulsifying agents and acidify the media. Further, the microbes producing these conditions should be tolerant to high salt concentrations and be capable of metabolizing high molecular weight compounds. Since oil reservoirs are also subject to temperature and pressure variations, successful microbial strains should be able to adapt to such environments. Thermophilic microorganisms, which usually live in harsh environments, appear to be good candidates for MEOR. Continuing work in Brookhaven National Laboratory dealing with the chemistry and biochemistry of microorganisms living under extreme conditions has been expanded to a systematic study of the interaction of thermophilic microorganisms with crude oils and oil derivatives. Some recent results of these studies are presented.
Break-up fees and bargaining power in sequential contracting

Abstract When a buyer negotiates in sequence with two potential sellers of a good, the outcome of each negotiation depends on all three players' bargaining powers. Assuming all parties are symmetrically informed, we find that the first seller's payoff is increasing in his own and the second seller's bargaining power. On the other hand, the second seller's payoff is decreasing in the first seller's bargaining power and, in some cases, also in his own bargaining power. We characterize when contracts will contain break-up fees. All results extend to the case of a seller negotiating in sequence with two buyers.
The Tuberous Sclerosis Complex Regulates Trafficking of Glucose Transporters and Glucose Uptake

Human cancers often display an avidity for glucose, a feature that is exploited in clinical staging and response monitoring by using 18F-fluoro-deoxyglucose (FDG) positron emission tomography. Determinants of FDG accumulation include tumor blood flow, glucose transport, and glycolytic rate, but the underlying molecular mechanisms are incompletely understood. The phosphoinositide-3 kinase/Akt/mammalian target of rapamycin complex (mTORC) 1 pathway has been implicated in this process via the hypoxia-inducible factor alpha-dependent expression of vascular endothelial growth factor and glycolytic enzymes. Thus, we predicted that tumors with elevated mTORC1 activity would be accompanied by high FDG uptake. We tested this hypothesis in eight renal angiomyolipomas in which the loss of tuberous sclerosis complex (TSC) 1/2 function gave rise to constitutive mTORC1 activation. Surprisingly, these tumors displayed low FDG uptake on positron emission tomography. Exploring the underlying mechanisms in vitro revealed that Tsc2 regulates the membrane localization of the glucose transporter proteins (Glut)1, Glut2, and Glut4, and, therefore, glucose uptake. Down-regulation of cytoplasmic linker protein 170, an mTOR effector, rescued Glut4 trafficking in Tsc2−/− cells, whereas up-regulation of Akt activity in these cells was insufficient to redistribute Glut4 to the plasma membrane. The effect of mTORC1 on glucose uptake was confirmed using a liver-specific Tsc1- deletion mouse model in which FDG uptake was reduced in the livers of mutant mice compared with wild-type controls. Together, these data show that mTORC1 activity is insufficient for increased glycolysis in tumors and that constitutive mTOR activity negatively regulates glucose transporter trafficking.
RRKM Theory beyond the Separable Harmonic Approximation: The HCO2 → H + CO2 Unimolecular Decomposition

We report variational calculations of a large number of vibrational states of HCO2 and the H···CO2 transition state for J = 0 using the code MULTIMODE and a realistic six degree-of-freedom potential energy surface. State-dependent rotational constants for both species are calculated for the same sets of vibrational states from exact rotation/vibration calculations for J = 1. The results of these variational calculations are used to obtain RRKM rate constants for the decomposition of HCO2 to form H + CO2. Comparison is made between these nonseparable RRKM results and those obtained from a standard, separable harmonic oscillator/rigid rotor evaluation of the RRKM rate constant expression. Significant differences between the nonseparable and separable results are found.
Adding an International Dimension to the Curriculum

(1990). Adding an International Dimension to the Curriculum. The Social Studies: Vol. 81, No. 4, pp. 166-170.
Impact of a risk-based prevention policy on neonatal group B streptococcal disease

Abstract Objective: Neonatal group B streptococcal infections can be prevented by intrapartum antibiotic prophylaxis. Beginning in 1992, women with obstetric risk factors at University of Miami–Jackson Memorial Medical Center were targeted to receive intrapartum antibiotic prophylaxis. We evaluated these preventive efforts. Study Design: A case was defined as isolation of group B streptococci from a sterile site in an infant Results: Group B streptococcal cases declined from 1.7 cases/1000 live births to 0.2 cases/1000 live births (Poisson regression, P = .002). Intrapartum antibiotic prophylaxis use increased from 13% of preterm deliveries in 1992 to 42% in 1995, and from 20% of deliveries with prolonged rupture of membranes in 1992 to 72% in 1995 (χ 2 test for linear trend P = .007 and P Conclusion: Provision of intrapartum antibiotic prophylaxis on the basis of risk factors was associated with decreased group B streptococcal disease. (Am J Obstet Gynecol 1998;179:1568-71.)
LCDD: A complete detector description package

Abstract LCDD has been developed to provide a complete detector description package for physics detector simulations using Geant4. All aspects of the experimental setup, such as the physical geometry, magnetic fields, and sensitive detector readouts, as well as control of the physics simulations, such as physics processes, interaction models and kinematic limits, are defined at runtime. Users are therefore able to concentrate on the design of the detector system without having to master the intricacies of C++ programming or being proficient in setting up their own Geant4 application. We describe both the XML-based file format and the processors which communicate this information to the underlying Geant4 simulation toolkit.
The Effectiveness of Marketing's “R&D” for Marketing Management: An Assessment:

This article presents some of the highlights and recommendations of the Commission on the Effectiveness of Research and Development for Marketing Management. Based on a review of the field of marke...
Compact single air interface bends in PFCB polymer waveguides

Compact waveguide bends and splitters are important components to enable dense integration of many functions on a single photonic chip. A common approach is to use a waveguide material system in which a large refractive index contrast between the core and clad materials is available. This permits a small bend radius to be used while still achieving high optical efficiency for the bend. However, such material systems generally have higher propagation loss than is possible with low refractive index contrast material systems such as silica. In this presentation we examine an approach to make the bend size essentially independent of the core/clad refractive index contrast using total internal reflection from a planar interface. We show through both 2D and 3D finite difference time domain (FDTD) simulation that very high bend efficiencies are possible when the correct bend design principles are adhered to. We illustrate this in practice with single air interface bends (SAIBs) in a PFCB material system with approximately 1% refractive index contrast. We experimentally demonstrate 45 degree bends with 0.3 dB loss per bend, and discuss the effects of fabrication issues such as misalignment, etch undercut, and etch roughness.
A practical guide to developing effective web-based learning.

OBJECTIVE: Online learning has changed medical education, but many “educational” websites do not employ principles of effective learning. This article will assist readers in developing effective educational websites by integrating principles of active learning with the unique features of the Web. DESIGN: Narrative review. RESULTS: The key steps in developing an effective educational website are: Perform a needs analysis and specify goals and objectives; determine technical resources and needs; evaluate preexisting software and use it if it fully meets your needs; secure commitment from all participants and identify and address potential barriers to implementation; develop content in close coordination with website design (appropriately use multimedia, hyperlinks, and online communication) and follow a timeline; encourage active learning (self-assessment, reflection, self-directed learning, problem-based learning, learner interaction, and feedback); facilitate and plan to encourage use by the learner (make website accessible and user-friendly, provide time for learning, and motivate learners); evaluate learners and course; pilot the website before full implementation; and plan to monitor online communication and maintain the site by resolving technical problems, periodically verifying hyperlinks, and regularly updating content. CONCLUSION: Teaching on the Web involves more than putting together a colorful webpage. By consistently employing principles of effective learning, educators will unlock the full potential of Web-based medical education.
Ulcerative colitis and Crohn disease: gene expression profiling using oligonucleotide microarrays

Inflammatory bowel disease (IBD) is a progressive, recurrent gastrointestinal disorder influenced by genetic, immunoregulatory and environmental factors and often requiring surgery for treatment. Ulcerative colitis (UC) and Crohn disease (CD), the two most common forms of IBD, have similar demographic and epidemiological features, but differ in intestinal tissue damage and prognosis. UC is associated with mucosal and submucosal injury involving the rectum and adjacent colon, whereas CD is associated with extensive transmural damage involving any segment of the colon. Both phenotypes are likely the outcome of small changes in expression of many regulatory genes, with consequent changes in expression of genes encoding cellular and extracellular matrix proteins. To understand the overall gene expression and dynamics in UC and CD we have performed expression profiling using oligonucleotide microarrays.
The use of pontryagin estimators for on-line optimal control sequence estimation: The truck backer-upper case study

The Pontryagin optimality principle can be used in conjunction with on-line (or real-time) measurements of state data to build a local model of the control law. In this paper, we discuss and refine the use of this technique in the context of the simple truck backer-upper problem. We first compare the use of feedforward, associative and CMAC neural architectures for the local control model encoding. Algorithm implementation is then done using the CMAC architecture because of its speed of learning and local scoping. We build temporal difference state prediction models for the truck dynamics and then use these predictions to build an estimate of the best control action to take. This control action is constructed from a depth first tree search used in conjunction with optimal control information obtained by solving locally scoped control problems via the Pontryagin optimality principle. The state to control model can then be encoded into a variety of function approximation models.
Tungsten carbide nanopowder by plasma-assisted chemical vapor synthesis from WCl6-CH4-H2 mixtures

Nanosized tungsten carbide powder was prepared by a thermal plasma process using tungsten hexachloride (WCl6) as the precursor. The reduction and carburization of the vaporized precursor by methane–hydrogen mixtures produced nanosized WC1−x powder, which sometimes contained WC and/or W2C phase. The effects of the molar ratio of reactant gases, plasma torch power, the flow rate of plasma gas, and the addition of secondary plasma gas (H2) on the product composition and grain size were investigated. The tungsten carbide powder produced by the plasma process showed particle sizes less than 20 nm. The produced powder was heated in hydrogen to fully carburize the WC1−x, and W2C phases to the WC phase as well as to remove excess carbon in the product. Finally, WC powder with particle size less than 100 nm was obtained.
Relational developmental systems: A paradigm for developmental science in the postgenomic era

This commentary argues that the anomalies suffered by the population behavior genetics paradigm are more widespread than suggested by Charney, including many made in the field of developmental science. Further, it is argued that, according to the criteria established by Kuhn, there is and has been available an alternative scientific paradigm that provides the formative context for Charney's postgenomic view. This is the relational developmental systems paradigm.
The skeleton in the closet: should historians of science care about the history of mathematics?

ABSTRACTUp until the 1950s, the history of mathematics was an integral part of the history of science. To George Sarton and his contemporaries, mathematics was the rational skeleton that organized science and held it together, and its history was a fundamental component of the broader history of science. But when historians began focusing on the cultural roots of science rather than its rational structure, the study of mathematics was marginalized and ultimately excluded from the history of science. The alienation between the two fields is detrimental to both, and in recent years there has been a sustained effort to reestablish meaningful communication between the two. This time, however, mathematics is seen not as the static skeleton of science but, instead, as a dynamic and historically evolving field in its own right—just like science itself. The new approach allows for a culturally sensitive study of mathematics, as well as a new and fruitful relationship between the history of science and the history...
A free‐formulation‐based flat shell element for non‐linear analysis of thin composite structures

A flat shell element based on the free-formulation finite element concept is developed for analysing geometrically non-linear thin composite shells. A corotational form of the updated Lagrangian formulation is utilized. Numerical results for typical validation problems are presented in order to demonstrate the accuracy and validity of this element. These results are obtained by solving the incremental equilibrium equations through the cylindrical arc-length method.
Changes in the behavior of laboratory-reared rhesus monkeys following the threat of separation

Four heterosexual pairs of three-year-old rhesus monkeys were either repeatedly separated from each other for 30-min or not separated. Prior to each separation, a transfer cage was displayed at the front of the cage to serve as a cue that the pair would be separated. After only a few trials, the animals displayed disturbance, particularly in the form of stereotyped pacingprior to the separation. Practical considerations related to laboratory methodology, a theoretical discussion concerning the fear of separation in monkeys and man, and the need for attention to individual differences in response to separation were emphasized.
Age‐related changes in antibody repertoire: contribution from T cells

Summary: The immune system of aged mice produces antibodies that are characterized by low affinity, diminished protection against infections and autoreactivity. It has been shown that these antibodies may be encoded by different immunoglobulin V genes and that the mechanism of somatic hypermutation in the V genes is inefficient. Studies on scid mice reconstituted with B and T cells from donors of different ages suggested that both lymphocyte subsets may contribute to the age-related changes in antibody repertoire. With help provided by T cells from young mice, the response to a hapten, nitrophenyl(acetyl), became gradually dominated by B-cell clones that rearranged a particular germline VH gene (V186.2). However, help from the aged T cells resulted in A heterogeneous response of B cells expressing many different V segments. Analysis of discrete foci of primary antibody-forming cells suggested that the aged T-helper cells are unable to govern the normally-occurring competition between the B-cell clones that have different affinities for the hapten. It is proposed that a signaling disequilibrium from the aged T cells, which provide less efficient help in quantitative terms, supports the growth of low-affinity B cells. This process may be exacerbated due to the apparent hyperactivity of aged B cells to CD40-mediated mitogenic signal.
Emily Dickinson: a research guide

Purpose – This paper aims to provide a guide to significant primary and secondary resources relevant to the study of Emily Dickinson and her poetry.Design/methodology/approach – Online catalogs, bibliographies, and the worldwide web were searched to identify relevant items. In some cases, citation analysis and other bibliometric measures were used to determine the highest‐impact sources. Items were annotated after personal examination by the author. The paper is divided into two main sections: primary sources (anthologies, databases and web resources) and secondary sources (bibliographies, databases, biographical resources, reference resources, monographs, journals and web resources).Findings – The paper introduces each resource, indicating its scope and contribution to the study of Dickinson. It acknowledges in particular the developments in recent Dickinson scholarship.Originality/value – Dickinson remains popular among both scholars and laypeople, but the most recent bibliographies of Dickinson scholar...
Quantification and interpretation of total petroleum hydrocarbons in sediment samples by a GC/MS method and comparison with EPA 418.1 and a rapid field method.

Total petroleum hydrocarbons (TPH) as a lumped parameter can be easily and rapidly measured or monitored. Despite interpretational problems, it has become an accepted regulatory benchmark used widely to evaluate the extent of petroleum product contamination. Three currently used methods (GC/MS, conventional EPA 418.1, and a rapid field method PetroFLAG) were performed to quantify the TPH content in samples collected from a site contaminated by transformer oil. To standardize the method and improve the comparability of TPH data, crucial GC-based quantification issues were examined, e.g., quantification based on internal standards (ISTD) vs external standards (ESTD), single vs multiple ISTD, and various area integration approaches. The interpretation of hydrocarbon chromatographic results was examined in the context of field samples. The performance of the GC/MS method was compared with those of EPA 418.1 and PetroFLAG. As a result, it was observed that the ISTD quantification method was preferred to the ESTD method, multiple ISTD might be better than single ISTD, and three different area integration approaches did not have a significant effect on TPH results. Evaluation of the chromatograms between a reference sample and three unknown samples showed that the extent of contamination varied appreciably with sample depth. It was also found that there existed a good positive correlation between GC/MS and both EPA 418.1 and PetroFLAG, and that EPA 418.1 produced the higher overall estimate while GC/MS and PetroFLAG resulted in lower, more statistically comparable TPH values.
A structure theorem for the elementary functions and its application to the identity problem

This paper uses elementary algebraic methods to obtain new proofs for theorems on algebraic relationships between the logarithmic and exponential functions. The main result is a multivariate version of a special case of the structure theorem due to Risch that gives, in a very explicit fashion, the possible algebraic relationships between the exponential and logarithm functions. The structure theorem has important applications to symbolic mathematical computation in that it in essence provides a canonical form for the elementary transcendental functions, and hence solves the identity problem for this class of functions. Such applications are discussed in the last section.
Brazilian street children: Contextual influences in relation to substance misuse

EnglishThis article reviews the socioeconomic and political context of substance misuse by street children in Brazil. Although findings are limited, available research reveals an urgent need for implementation of policies for street children. Programs for preventing substance misuse and delinquency are still missing political and infrastructural support.FrenchCette etude analyse le contexte politique et socioeconomique qui entoure le mauvais emploi de substances par les enfants de la rue du Bresil. Bien que les resultats soient limites, la recherche indique que l'etablissement de politiques concernant les enfants de la rue est un enjeu urgent. Il n'y a pas encore de cadre politique et d'infrastructures pour soutenir les programmes de prevention de la consommation et de la delinquance.SpanishEste articulo revisa el contexto socioeconomico y politico del fundamento del abuso de ninos de la calle en Brasil. Aunque los hallazgos son limitados, la investigacion disponible revela una urgente necesidad de implem...
Leadership style and organizational innovativeness drive motor carriers toward sustained performance

Purpose – The purpose of this study is to examine the complex relationships between transformational leadership, organizational innovativeness, and motor carrier performance.Design/methodology/approach – A covariance‐based structural equation model was developed, tested and validated to explain the effect of leadership style and innovativeness on motor carrier performance. The authors’ hypotheses were tested using responses from 158 North American motor carriers.Findings – The results support a direct as well as an indirect positive relationship between transformational leadership and organizational performance. Through the theoretical lens of dynamic capabilities theory, the results indicate that leaders motivate organizational change based on their own idiosyncrasies and perceptions of the environment.Research limitations/implications – This research was limited by its focus on the motor carrier industry and may limit the generalizability of the findings. While the sample of motor carriers was selected ...
Effectiveness of amantadine hydrochloride in the reduction of chronic traumatic brain injury irritability and aggression

BACKGROUND:: Following traumatic brain injury (TBI), individuals may experience chronic problems with irritability or aggression, which may need treatment to minimize the negative impact on their relationships, home life, social interactions, community participation, and employment. OBJECTIVE:: To test the a priori hypothesis that amantadine reduces irritability (primary hypothesis) and aggression (secondary hypothesis) among individuals greater than 6 months post-TBI. METHODS:: A total of 76 individuals greater than 6 months post-TBI referred for irritability management were enrolled in a parallel-group, randomized, double-blind, placebo-controlled trial of amantadine (n = 38) versus placebo (n = 38). Study participants were randomly assigned to receive amantadine hydrochloride 100 mg twice daily versus equivalent placebo for 28 days. Symptoms of irritability and aggression were measured before and after treatment using the Neuropsychiatric Inventory Irritability (NPI-I) and Aggression (NPI-A) domains, as well as the NPI-Distress for these domains. RESULTS:: In the amantadine group, 80.56% improved at least 3 points on the NPI-I, compared with 44.44% in the group that received placebo (P = .0016). Mean change in NPI-I was -4.3 in the amantadine group and -2.6 in the placebo group (P = .0085). When excluding individuals with minimal to no baseline aggression, mean change in NPI-A was -4.56 in the amantadine group and -2.46 in the placebo group (P = .046). Mean changes in NPI-I and NPI-A Distress were not statistically significant between the amantadine and placebo groups. Adverse event occurrence did not differ between the 2 groups. CONCLUSIONS:: Amantadine 100 mg every morning and at noon appears an effective and safe means of reducing frequency and severity of irritability and aggression among individuals with TBI and sufficient creatinine clearance. Language: en
Effect of irradiation on stress corrosion cracking in supercritical water

Proton irradiation was used to study the effect of irradiation on stress corrosion cracking of 316L stainless steel and nickel-base alloy 690 in supercritical water (SCW). Irradiation to 7 dpa at 400 °C and 500 °C resulted in increased stress corrosion cracking (SCC) in SCW over the unirradiated case with the severity increasing with temperature. Irradiation results in significant radiation-induced segregation, formation of dislocation loops and voids (at 500 °C) and hardening. Neither RIS nor irradiation hardening correlates with SCC susceptibility.
Mechanical remodeling of the endothelial surface and actin cytoskeleton induced by fluid flow

Objective: The mechanism by which cultured endothelial cells respond to shear stress is controversial. The cell surface and cytoskeleton are involved, but their roles are undefined. In this study, previously unknown changes in the surface detail and actin cytoskeleton of bovine aortic endothelial cells were identified.Methods: Actin filament content and filament number in resting and flow-oriented cells were determined by biochemical assays. The three-dimensional organization of the actin cytoskeleton in cells was defined in the confocal microscope and in the electron microscope after rapid-freezing, freeze-drying, and metal coating of detergent-permeabilized cells.Results: Endothelial cells have smooth apical membranes in situ. However, cultured cells exhibit surface microvilli which increase the apical surface area, exposing the ruffled surface to forces from fluid flow and potentially enhancing cell interactions with blood-borne white cells. Stereoscopic micrographs show that stress fibers are integrat...