cssi/SciSciGPT-SciSciNet huggingface dataset:
Argument-Driven Inquiry: An Introduction to a New Instructional Model for Use in Undergraduate Chemistry Labs

This article presents a new instructional model called Argument-Driven Inquiry (ADI) that can be used in undergraduate college chemistry laboratory courses. ADI is designed to provide students with an opportunity to develop their own method to generate data, to carry out investigations, use data to answer research questions, write, and be more reflective as they work. In addition, the ADI instructional model integrates opportunities for students to engage in scientific argumentation and peer review. This article describes the ADI instructional model, provides the empirical and theoretical foundation for it, and presents a detailed semester pacing schedule for general chemistry I laboratories, peer-review guides, and instructor scoring rubrics.
Dynamics of delayed systems under feedback control

Abstract We study the dynamics of a general system under linear feedback control subject to system, measurement and actuator delays. There are two general classes of dynamic behavior, resonant and nonresonant, which are pertinent to the tuning of the controllers and to the nonlinear closed-loop dynamics. For non-resonant systems, the corss-over frequency and ultimate gain are monotonic and continuous functions of the delay and conventional Ziegler—Nichols type tuning methods are appropriate. For resonant systems, however, the cross-over frequency is a discontinuous function of the delay and at certain critical values of the delay, two cross-over frequencies coexist at the same ultimate gain. Such systems cannot be tuned with the Ziegler—Nichols methods. These critical delays of a resonant system correspond to double-Hopf bifurcation points with two distinct pairs of purely imaginary eigenvalues (closed-loop poles). Using center manifold projection and normal form analyses, we are able to predict all nonlinear dynamics in the vicinity of these singularities. In particular, a two-frequency torus is always found. This is verified experimentally in a cascaded liquid level control system. There is also evidence that the torus degenerates into a chaotic attractor as the feedback gain is increased.
Beneficial effects of an open artery on left ventricular remodeling after myocardial infarction

During the last 2 decades researchers have developed a clearer understanding of the pathophysiology of acute myocardial infarction (AMI). The use of thrombolysis and coronary angioplasty early in the course of AMI salvages myocardium and preserves left ventricular function, which results in improved survival rates. Late reperfusion after AMI, however, may provide beneficial effects on long-term prognosis, especially owing to attenuation of left ventricular remodeling. This article reviews the evidence of the benefits of an open infarct-related artery on left ventricular remodeling after AMI.
The Burden of Proof: A Quantitative Study of High-Achieving Black Collegians

This study employed hierarchical linear regression techniques to study the relationship between GPA and the extent to which high-achieving black collegians’ feel pressure to prove their intellectual ability using survey data from participants at a predominantly white institution. Findings suggest that approximately 88% of high-achieving black collegians report feeling pressure to prove their intellectual ability, despite prior achievements and participation in a university scholarship program. Regression results were not statistically significant for the tie between GPA and the degree of psychological burden reported; however other variables account for 27% of the variance in GPA and hold promise for future practice and research on high-achieving blacks.
Trade and Global Income Inequality with Frictional Labor Markets: A Lesson from the Canada–US Free Trade Agreement

AbstractThis paper develops a two-country trade model with frictional labor market structures to investigate the link between increased openness to trade and cross-country income inequality. Calibrated to US–Canadian data, the model simulation results show that the Canada–US Free Trade Agreement benefited Canada, the country with relatively higher capital intensity, more due to its capacity to flexibly expand in response to an increase in product demand. The results from counterfactual experiments indicate that increased capital intensity in the US is expected to increase gains from trade in both countries while making the distribution of gains less unequal.
Complementation of pulmonary abnormalities in SP-D(-/-) mice with an SP-D/conglutinin fusion protein.

Surfactant protein D (SP-D) and serum conglutinin are closely related members of the collectin family of host defense lectins. Although normally synthesized at different anatomic sites, both proteins participate in the innate immune response to microbial challenge. To discern the roles of specific domains in the function of SP-D in vivo, a fusion protein (SP-D/Congneck+CRD) consisting of the NH2-terminal and collagenous domains of rat SP-D (rSP-D) and the neck and carbohydrate recognition domains (CRDs) of bovine conglutinin (Cong) was expressed in the respiratory epithelium of SP-D gene-targeted (SP-D(−/−)) mice. While SP-D/Congneck+CRDfusion protein did not affect lung morphology and surfactant phospholipid levels in the lungs of wild type mice, the chimeric protein substantially corrected the increased lung phospholipids in SP-D(−/−) mice. The SP-D/Congneck+CRD fusion protein also completely corrected defects in influenza A clearance and inhibited the exaggerated inflammatory response that occurs following viral infection. However, the chimeric protein did not ameliorate the ongoing lung inflammation, enhanced metalloproteinase expression, and alveolar destruction that characterize this model of SP-D deficiency. By contrast, a single arm mutant (RrSP-DSer15,20) partially restored antiviral activity but otherwise failed to rescue the deficient phenotype. Our findings directly implicate the CRDs of both SP-D and conglutinin in host defense in vivo. Our findings also strongly suggest that the molecular mechanisms underlying impaired pulmonary host defense and abnormal lipid metabolism are distinct from those that promote ongoing inflammation and the development of emphysema.
Spontaneous synchronized calcium oscillations in neocortical neurons in the presence of physiological [Mg2+]: involvement of AMPA/kainate and metabotropic glutamate receptors

Primary cultures of neocortical neurons exhibit spontaneous Ca(2+) oscillations under zero or low extracellular [Mg(2+)] conditions. We find that mature murine neocortical neurons cultured for 9 days also produce spontaneous Ca(2+) oscillations in the presence of physiological [Mg(2+)]. These Ca(2+) oscillations were action potential mediated inasmuch as tetrodotoxin eliminated their occurrence. AMPA receptors were found to regulate the frequency of Ca(2+) oscillations. In contrast, Ca(2+) oscillations were independent of activation of L-type Ca(2+) channels, and NMDA receptors provided only a minor contribution. Release of intracellular Ca(2+) stores was involved in the oscillatory activity since thapsigargin reduced the amplitude and frequency of the oscillations. S-4-carboxyphenylglycine (S)-4CPG), an antagonist of group I metabotropic glutamate receptor (mGluR), also reduced the amplitude of oscillations. In addition, 1-aminocyclopentane-trans-1,3-dicarboxylic acid (trans-ACPD), a group I mGluR agonist, increased the oscillation frequency, suggesting a critical role for mGluR in the generation of Ca(2+) oscillations. The mGluR-mediated release of intracellular Ca(2+) stores appeared to be mediated by phospholipase C (PLC) since the PLC inhibitor U73122 eliminated the Ca(2+) oscillations. These results indicate that Ca(2+) oscillations in neocortical cultures in the presence of physiologic [Mg(2+)] are primarily initiated by excitatory input from AMPA receptors and involve mobilization of intracellular Ca(2+) stores following activation of mGluR.
Function of “Nontrauma” Surgeons in Level I Trauma Centers in the United States

Although the general "trauma" surgeon is usually the team leader in level I trauma centers, the use of surgical subspecialists and nonsurgeons is frequently ill-defined. This study was done to gain data in regard to actual use of subspecialists in busy centers. First, a survey of the patterns of staffing in 140 trauma centers was elicited by mail questionnaire, supplemented by telephone cells. Second, records of 400 consecutive patients at the Elvis Presley Trauma Center were reviewed to determine the use of subspecialists during the first 24 hours of care of individual patients. There were differences in the use of surgical subspecialists and nonsurgeons at different centers: in receiving, admitting, operating, and critical care areas and in privileges for admission and attending of inpatients. Consultation "guidelines" are used for many specific injuries. At our center, a mean of 1.92 subspecialists, in addition to general surgeons, were involved in the early care of each patient. Problems exist in many centers regarding the use of subspecialists, especially for management of facial and chest injuries. In some centers nonsurgeons function in the intensive care unit, and as admitting and attending physicians of trauma patients.
“Making a Way”: Young Women Using Literacy and Language to Resist the Politics of Silencing

Urban public schools are often contexts in which students are beset with silencing, surveillance, and low expectations. These conditions present distinct and critical challenges to young women. This article explores the language and literacy practices that emerged in an in-school elective writing and photography course designed with and for young women of color. Drawing on the students' poetry and an emergent discussion of the war in Iraq, the author argues that the students used language and literacy to transgress the politics of silencing within schools. Through an analysis of the students' efforts to claim agency and credibility within and against dominant discourses and within their school, the author argues that literacy-rich contexts can be created within schools to assist young women in “making a way.” The article draws from a 10-month teacher research study into the design and enactment of the course.
SU-E-T-309: Tangential Modulated Arc Therapy: A Novel Technique for the Treatment of Superficial Disease

Purpose: We propose a new type of treatment that employs a modulated and sliding tangential photon field to provide superior coverage of superficial targets when compared to other commonly employed methods while drastically reducing dose to the underlying sensitive structures often present in these cases. Methods: Modulated treatment plans were formulated for a set of three representative cases. The first was a revised treatment of a scalp sarcoma, while the second was a treatment of a right posterior chest wall sarcoma. For these cases, asymmetric jaw placement, angular limitations, and central isocenter placements were used to force the optimization algorithm into finding solutions with beamlines that were not perpendicular to the body surface. The final case targeted the chest wall of a breast cancer patient, in which standard treatments were compared to the use of modulated fields with multiple isocenters along the chest wall. Results: When compared with unrestricted modulated arcs, the tangential arc scalp treatment reduced the max and mean doses delivered to the brain by 33Gy (from 55 to 22Gy) and 6Gy (from 14Gy to 8Gy), respectively. In the right posterior chest wall case, the V10 in the ipsilateral lung was kept below 5% while retaining a Rx dose (45Gy) target coverage of over 97%. For the breast case, the modulated plan achieved reductions in high dose to the ipsilateral lung and heart by a factor of 2–3 when compared to classic laterally opposed tangents and reduced the V5 by 40% when compared to standard modulated arcs. Conclusion: Tangential modulated arc therapy has outperformed the conventional modalities of treatment for superficial lesions used in our clinic. We hope that with the advent of digitally controlled linear accelerators, we can uncover further benefits of this new technique and extend its applicability to a wider section of the patient population.
Preferential Use of “Off Pump” Glenn Shunts: A Single‐Center Experience

Objective. The objective of this study was to provide a descriptive comparison of a single institution's experience with preferential Glenn shunts performed with and without cardiopulmonary bypass. Introduction. For single ventricle heart diseases, the bidirectional superior cavopulmonary shunt serves as an effective palliation. It has been the preference at our institution to perform Glenn shunts without cardiopulmonary bypass whenever possible. We compared results of Glenn procedures carried out with and without cardiopulmonary bypass. Methods. All patients who received Glenn shunts at our institution between January 2000 and July 2007 were reviewed. During this time period, Glenn shunts were performed without cardiopulmonary bypass in all cases in which side clamping of the pulmonary artery was tolerated. “Off pump” Glenn shunts were performed using a temporary superior vena cava to right atrium shunt. Results. Sixty-five patients received bidirectional Glenn shunts during the study period. Thirty-five were performed off cardiopulmonary bypass. Thirteen patients received bilateral bidirectional Glenn shunts, six of which were performed off pump. There was one patient who did not tolerate the off-pump Glenn shunt and was converted to the on-pump procedure. There was no significant difference in postoperative success as determined by measurements of pressure gradients across the anastomoses, length of intensive care unit stay, intubation time, length of hospital stay, and 30-day mortality. There were no cases of intraoperative mortality in either group. Conclusion. The bidirectional Glenn shunt can be performed safely without cardiopulmonary bypass in the majority of cases. Cardiopulmonary bypass is indicated when clamping of the pulmonary arteries is not tolerated.
Assembly process for high bandwidth density organic optical MCM

We develop a high-bandwidth density organic optical multi-chip module (MCM). A high packaging density is achieved by integrating bare optical chips, developing compact fiber connectors that connect perpendicularly to the surface of the module, and manufacturing total internal reflection mirrors by a precise laser ablation technique. An assembly procedure for the optical MCM is established. It is verified that the organic MCM is resistant to heat of reflow processes and that mirror quality does not degrade due to the lens array assembly process.
From Life to Existence: A Reconsideration of the Question of Intentionality in Michel Henry’s Ethics

Michel Henry has renewed our understanding of life as immanent affectivity: life cannot be reduced to what can be made visible; it is – as immanent and as affectivity – radically invisible. However, if life (la vie) is radically immanent, the living (le vivant ) has nonetheless to relate to the world: it has to exist . But, since existence requires and includes intentional components, human reality – being both living and existing – implies that immanence and intentionality be related to one another, even though they are conceived at the same time as radically distinct modes of appearing in Henry’s phenomenology of life. Following this line of thought, we are faced with at least two questions: First, what reality does immanent appearing have for us as existing and intentional beings? And second, from an ethical point of view, what does Henry’s opposition of “barbarism” and “second birth” mean in terms of existence? As will be shown, it follows from the standpoint of radical phenomenology itself that immanent affectivity has reality for us only insofar as it finds its expression or translation in the realm of the intentionally visible and that, with regard to ethics, both “barbarism” and its overcoming in “second birth” are effective only insofar as they are mediated through representations. Henry’s critique of representation and intentionality needs therefore to be revised, especially in the field of practical philosophy, where the essential role played by intentionality has to be acknowledged even by radical phenomenology.
Dimethyl Sulfoxide Protects Tightly Coupled Mitochondria from Freezing Damage

Dimethyl sulfoxide prevented loss of respiratory control and decrease in efficiency of oxidative phosphorylation when plant mitochondria were stored in liquid nitrogen. Respiration was severely inhibited and was not stimulated by adenosine diphosphate when mitochondria were frozen in liquid nitrogen without dimethyl sulfoxide. Thus, isolated mitochondria provide a model system for the study of the effects of freezing on biological membranes and of the prevention, by dimethyl sulfoxide, of freezing damage.
Type I cAMP-dependent Protein Kinase Delays Apoptosis in Human Neutrophils at a Site Upstream of Caspase-3

Current data suggest that apoptosis controls neutrophil numbers in tissues. We analyzed roles for and the sites of action for the cAMP-dependent protein kinases (cAPKs) in apoptosis induced in human neutrophils by in vitro storage, cycloheximide (CHX) exposure, and anti-Fas exposure. Treatment with 8-chlorophenylthio-cAMP (8-CPT-cAMP) prolonged the time required for 50% of the cells to exhibit apoptotic morphology (t50) from 16.3 to 41.8 h (in vitro culture), from 2.4 to 7.8 h (CHX), and from 4.8 to 6.5 h (anti-Fas). CHX +/- 8-CPT-cAMP did not significantly alter resting intracellular calcium levels and H-89, a selective inhibitor of cAPK, had no effect on apoptosis in the absence of the analogue. In contrast, site-selective cAMP analogues that specifically activated the type I cAPK, but not type II cAPK, synergistically attenuated apoptosis. Exposure to 8-CPT-cAMP delayed, in parallel, the activity of caspase-3 (CPP-32beta), whereas mitogen-activated protein kinase kinase (MAPKK) inhibitor, PD98059, had no effect on CHX-induced apoptosis +/- 8-CPT-cAMP. Together these results indicate that type I cAPK activation is necessary and sufficient to mediate cAMP-induced delay in human neutrophil apoptosis induced by several mechanisms and suggest that one of the major sites of cAPK action is upstream of caspase-3 (CPP-32beta) activation.
A T1 lattice relaxation study of the molecular motions of a semicrystalline polyimide matrix

The kHz molecular motion of a semicrystalline polyimide was studied through 13 C solid state NMR spectroscopy. Variable temperature T 1ρ experiments were performed on a Bruker msl-300 spectrometer for various B 1 applied radio frequency fields. Similar activation energies of motion for different carbon atoms in the flexible spacer gave evidence of a group motion of this molecular segment. It was also found that aromatic activation energies were higher than those of aliphatic carbons.
C-reactive protein increases F-actin assembly and cortical distribution with resultant loss of lamellipod formation in human neutrophils.

C-reactive protein (CRP) inhibits neutrophil movement through a p38 MAP kinase pathway. We hypothesized that CRP altered F-actin content and distribution on human neutrophils as a means of inhibiting movement. CRP produced simultaneous increased F-actin and decreased G-actin levels. CRP increased F-actin levels in a concentration-dependent manner once a threshold (>100 μg/ml) was reached, and transiently increased F-actin (peak levels at 2.5 and 10 min) that returned to baseline by 30 min. Confocal microscopy of neutrophils revealed that fMLP provoked acquisition of a migratory phenotype as evidenced by the appearance of F-actin rich lamellipods. In contrast, CRP caused neutrophil rounding, prevented lamellipod formation and shifted F-actin from the cytoskeleton to the cortex. The p38 MAP kinase inhibitor, SB203580, produced a similar effect on neutrophil shape. Concentrations of SB203580 that dramatically decreased p38 activity in neutrophils also caused round cell morphology and cortical F-actin distribution. Since CRP inhibits p38 MAP kinase and p38 blockade leads to actin polymerization and prevention of lamellipod formation, it is concluded that round morphology and loss of lamellipod formation result from CRP inhibition of p38 MAP kinase. Understanding the signal transduction of CRP prevention of lamellipod formation will aid in the development of therapeutic agents against neutrophil-associated inflammatory disease.
AGRICULTURAL POLICY AS A SOCIAL ENGINEERING TOOL: A NEW JERSEY CASE STUDY

This study uses logistic regression to examine the preferences for social engineering policies in the agricultural sector in a New Jersey case study. It finds that farm operators are unlikely to support a policy allowing countries to restrict trade to pursue domestic economic and social policy goals if the policies affect international trade. In particular, it suggests that farm operators with annual gross sales including government payments between $500 000 and $999 999 are 80 percent less likely to indicate such a preference. Farm operators with advanced degrees, some college education, and a high school diploma are also unlikely to indicate such a preference. In contrast, farm operators who receive no income from farming or ranching and those who receive a percentage of family income from farming or ranching indicate that countries should be allowed to restrict trade to pursue domestic economic and social policy goals even if the policies affect international trade.
Pulse compression techniques in nuclear medicine

A high-efficiency "chirped" linear array of pinholes for imaging a distribution of radioisotopes is described. The image is obtained in a coded or scrambled form, and then decoded using a dispersive surface acoustic wave delay line. Results of an optical simulation experiment are presented.
A One-Sided Aspect of Alfvenic Fluctuations in the Solar Wind

Using Advanced Composition Explorer (ACE) 64 s data at 1 AU we find that Alfvenic fluctuations propagating outward from the Sun along the magnetic field, B , in the solar wind often produce one-sided variations in one of the equatorial components of B and velocity, V . This is a natural consequence of the fact that the Alfvenic fluctuations are transverse fluctuations in which |B| remains nearly constant. Thus, fluctuations in the field component that defines the underlying background field direction are always relative to a base value rather than to an average value. This suggests that conclusions derived from statistical analyses of fluctuations in the solar wind that assume the fluctuations in all field components are relative to average values need to be re-examined. We also find that discrete, sunward-propagating Alfvenic fluctuations or rotational discontinuities are extremely rare in the pristine solar wind; thus far we have identified such discrete events in ACE data only in association with events identified as magnetic reconnection exhausts and/or in association with backstreaming ions from reverse shocks, including Earth's bow shock.
Adaptive filtering for noisy and mismatched conditions in speaker recognition

This paper presents comparison of different adaptive filter algorithms i.e. Wiener, Least Mean Square LMS, Normalized Least Mean Square NLMS, Block Least Mean Square, BLMS, as system identifiers of telephonic channel; specially when there is a mismatch in train and test conditions of speaker recognition system. We need to know the response of this telephonic channel in order to minimize the mismatch between training and testing data. Once this response is known we can get filter weights either to model telephonic channel and pass the clean speech through it or make and inverse system out of the identified coefficients in order to enhance the corrupted signal. Results are obtained on white Gaussian noise added signal and signal passed through telephonic channel. It has been seen that LMS and NLMS perform better over white Gaussian noise added signals whereas in case of mismatched train/test conditions, the better estimate of unknown telephonic channel response was given by LMS algorithm with small step size of 0.003 and then at 0.5, 0.6 step size. Effect of varying step size has been observed not only for LMS but it's variants as well. Overall results show significant improvement from 20% to 80-66% in speaker recognition accuracy.
Managerial auditors’ mixed cost forecasting assumption departure error estimates for litigation and professional liability risk reduction: the electronic security industry

Managerial auditors (MAs) are frequently relying on mistaken mixed costs (MC) forecasting assumptions. Two such assumptions are that MC are linear within the relevant range and variable costs vary proportionately with activity levels. Departure from these assumptions can lead to understating expenses, overstating profits, and even to fraud, litigation, and mounting professional liability risk. Develops a forecasting model of mixed cost error estimates, or error difference (ED). MAs can reduce the risk of litigation and professional liability by including such an ED in the internal control structure of a company. Uses Sensormatic Corporation and the electronics security industry as sample case because of the recent prominence of litigation and professional auditor liability verdicts. Focuses on the electronics security industry, but some of the findings may apply to other industries.
A Short-Term Longitudinal Study of Differential Sources of School-Related Social Support and Adolescents’ School Satisfaction

School is an important context for early adolescents’ development. An overall positive sense of well-being in school, measured by school satisfaction in this study, should be one of the indicators of a good schooling experience. To address the importance of social support in the school context, this study examined the relationship between three sources of school-related social support (family support for learning, peer support for learning, and teacher-student relationships) and early adolescents’ school satisfaction across time. Participants were 547 middle school students from a middle school in the Southeastern United States who completed surveys of school social climate and school satisfaction on two separate occasions, five months apart. Results showed that overall school-related social support explained a substantial amount of the variance associated with students’ school satisfaction reports at both time points. However, there were differential effects among three sources of social support. Specifically, teacher-student relationships accounted for the largest amount of variance in school satisfaction at Time 1 and Time 2 (controlling for Time 1); peer support contributed a statistically significant amount of unique variance to school satisfaction at Time 1; and family support significantly contributed to students’ school satisfaction at Time 2 (controlling for Time 1). Recommendations for educators, childcare workers, administrators, and policymakers are discussed in light of the findings and developmental considerations.
Growing Roles for Science Education in Community Colleges

In an increasingly global society and economy, education and training beyond compulsory primary and secondary education—especially in science, technology, engineering and mathematics (STEM)—is essential to a nation's competitiveness and its standard of living. Community colleges, originally developed at the turn of the 20th century as open-admissions junior colleges and offering the first two years of a baccalaureate education, help meet this need. These colleges have evolved into comprehensive institutions, preparing students to transfer to upper-division universities or to enter the workforce directly. Enrolling 43% of all U.S. undergraduates ( 1 ), community colleges play important roles in developing public scientific literacy, educating scientists and engineers, and addressing the nation's need for well-prepared technicians ( 2 ). But challenges remain.
The specification of physical attribute information for engineering analysis

This paper addresses the issue of specifying the functional information beyond that of the geometric domain of the object needed to qualify a problem in mathematical physics for which an engineering analysis is to be performed. A generalized geometry-based approach for the specification of this information is presented. This information, plus the domain definition to which it is tied, represents the complete specification of the problem to be analyzed.
Maxillofacial injuries associated with domestic violence.

Abstract Purpose: The purpose of this study was to report the incidence, causes, and patterns of maxillofacial injury associated with domestic violence. Patients and Methods: A retrospective review of patients treated for domestic violence injuries at an inner-city hospital over a 5-year period was done, and data were collected on type and location of injury, mechanism of injury, alcohol involvement, and treatment. Results: The sample consisted of 236 emergency room admissions. The majority (81%) of victims presented with maxillofacial injuries. The fist was a favorite means for assaults (67%). The middle third of the face was most commonly involved (69%). Soft tissue injuries were the most common type of injury (61%). Facial fractures were present in 30% of victims. The average number of mandible fractures per patient was 1.32. The majority of facial fractures (40%) were nasal fractures. Left-sided facial injuries were more common than right sided. Conclusions: These data confirm that most victims of domestic violence sustain maxillofacial injuries. Midface injuries predominate. The preponderance of facial injuries makes it very likely that oral and maxillofacial surgeons will be involved in the care of these patients. © 2001 American Association of Oral and Maxillofacial Surgeons
COMPARISON OF HALF-SATURATION CONSTANTS FOR GROWTH AND NITRATE UPTAKE OF MARINE PHYTOPLANKTON (2).

Growth rates and rates of nitrate uptake by N-depleted cells were measured for an oceanic diatom, Chaetoceros gracilis, and a neritic diatom, Asterionella japonica, as functions of nitrate concentration of the medium. Both growth and N-uptake rates appeared to be hyperbolic with nitrate concentration and could be fit to an equation of Michaelis-Menten form: where v is rate, V(m) . is the maximum rate, S is nitrate concentration, and Ks is the half-saturation constant. Ks values for uptake and growth were similar if not identical for each species. Uptake experiments can provide a presumptive measure of Ks for growth, thought to be an ecologically significant characteristic of a species.
Binding of Antibodies to Virion-Associated gp120 Molecules of Primary-like Human Immunodeficiency Virus Type 1 (HIV-1) Isolates: Effect on HIV-1 Infection of Macrophages and Peripheral Blood Mononuclear Cells

Using immunobiochemical approaches we previously studied the conformation and surface exposure of different immunodominant regions within the oligomeric, virion-associated form of the gp120 envelope glycoprotein of the human immunodeficiency virus type 1 (HIV-1) (L Stamatatos and C. Cheng-Mayer (1995) J. Virol. 69, 6191-6198). These studies allowed us to determine to what extent epitopes within these immunodominant regions of the oligomeric gp120 are occluded or accessible to antibody binding on the virion surface of two primary-like (HIV-1SF162 and HIV-1SF128A) and one. T-cell-line-adapted (HIV-1SF2) isolates. Here, we investigate whether binding of anti-gp120 monoclonal antibodies (MAbs) to exposed epitopes of the immunodominant regions of oligomeric gp120 results in neutralization of HIV-1 infection and whether certain exposed sites are better targets for neutralization than others. We also test whether proposed mechanisms for antibody-mediated neutralization of T-cell-line-adapted HIV-1 isolates, e.g., antibody-mediated gp120-virion dissociation, are applicable to primary-like HIV-1 isolates. We assess the neutralization potential of anti-V2 loop, anti-V3 loop, and anti-CD4 binding site MAbs using human primary macrophages or peripheral blood mononuclear cells (PBMC) as target cells and HIV-1SF162 and HIV-1SF128A as infecting isolates. Our data indicate that: (i) not every exposed epitope of the immunodominant regions of gp120 oligomers on the virion surface is a target for neutralization; (ii) during virus-cell fusion specific exposure of previously occluded V3 loop epitopes within gp120 oligomers occurs, which may become targets for neutralization; (iii) antibody-mediated gp120-virion dissociation does not appear to be a major mechanism of neutralization for the primary-like HIV-1 isolates tested here; and (iv) infection of macrophages is more sensitive to neutralization by anti-gp120 monoclonal antibodies than PBMC. We also report that binding of one of the two anti-CD4 binding site MAbs tested mediated enhancement of macrophage cell infection in a concentration-dependent fashion, while binding of the other anti-CD4 binding site MAb resulted in efficient neutralization of infection of both macrophages and PBMC.
On reconsidering community-based health promotion.

Merzel and D’Afflitti are to be commended for their excellent overview of community-based health promotion studies.1 The human immunodeficiency virus (HIV) prevention studies are a model for possible successful community intervention programs. These “successful” community intervention programs to change HIV risk behavior are not unique. They represent the classic “shoe leather” epidemiological prevention approach for control of sexually transmitted diseases by identifying high-risk populations, mode of transmission of the disease, recruitment of local or neighborhood advocates, and a defined intervention strategy. There have been previous successful community-based public health programs to control chronic diseases that serve as models for successful programs. Perhaps the earliest and most successful was the elimination of pellagra by dietary modifications in high-risk communities by Goldberger et al. in the early 1900s.2 Community-based tuberculosis programs were very successful in delivering isoniazid and other therapies to high-risk communities to reduce the number of new cases.3 Community-based programs were successful in reducing the risk of rheumatic heart disease and recurrent rheumatic fever among children with rheumatic fever even in very high-risk communities.4 The Hypertension and Detection Follow-up Program in the 1980s was a very successful community-based randomized trial to test antihypertensive therapy and reduction of stroke, congestive heart failure, coronary heart disease, and total mortality. The trial used health counselors to work with participants and demonstrated substantial improvement in adherence to antihypertensive therapy, reduction in blood pressure, and decrease in risk of vascular disease even among the lowestincome minority participants.5,6 These successful community studies have several characteristics in common: (1) a strong public health and preventive medicine science base7,8; (2) selection of an appropriate population in which to implement the intervention (i.e., common-source population, total population, or selected higher-risk subsample of population); (3) use of an intervention that has been shown to have an impact (efficacy) on defined measurable outcome and that will have a meaningful impact on the health of at-risk populations; (4) sufficient funding to provide an adequate, well-trained, and dedicated field staff to deliver the effective therapies; and (5) community support. I would strongly suggest a careful review of these successful public health programs of the past before we focus on new behavioral theories for community programs.9 Finally, the statement that these programs do not require evaluations with regard to reduction of incidence or mortality of disease or objective evidence of changes in risk factors is a serious mistake. Such an assumption could be the death knell of community-based public health programs in the future, especially since there is now greater emphasis on evidence-based outcomes as criteria for support.8,10 Unfortunately, many programs have good processes but are too weak to have any meaningful objective outcomes.
A Comparison of Linear Programming and Parametric Approaches to the Two‐Group Discriminant Problem*

Recent simulation-based studies of linear programming models for discriminant analysis have used the Fisher linear discriminant function as the benchmark for parametric methods. This article reports experimental evidence which suggests that, while some linear programming models may match or even exceed the Fisher approach in classification accuracy, none of the fifteen models tested is as accurate on normally distributed data as the Smith quadratic discriminant function. At the minimum, further testing is warranted with an emphasis on data sets that arise from significantly non-Gaussian populations.
Mycoplasma genitalium in cervicitis and pelvic inflammatory disease: Bjartling et al

532 American Journal of Obstetrics & Gynecology Mycoplasma genitalium (M genitalium) is a fairly unfamiliar entry in the catalog of sexually transmitted microorganisms. In fact, information on its role in urethritis and cervicitis is new to the Center for Disease Control and Prevention’s most recent Sexually Transmitted Diseases (STDs) Treatment Guidelines. Yet, this parasitic bacterium is now linked to 15-25% of the nongonoccocal urethritis cases that occur in the United States. Limited data also indicate that like Chlamydia trachomatis (C trachomatis) and Neisseria Gonorrhoeae, M genitalium can be a culprit in cervicitis and pelvic inflammatory disease (PID). In a new study, Bjartling and colleagues determined the prevalence of M genitalium in a gynecologic emergency clinic and then assessed all associated outcomes.
Long-Term Implications of Military Service for Later-Life Health and Well-Being

This introduction begins a special issue on Military Service in the Life Course: Implications for Later-Life Health and Well-Being. It highlights the pressing need for a lifespan approach to the effects of military service that considers positive and negative effects. The first two articles focus on Vietnam veterans. Park et al. examine how captivity stressors, mental health, and individuals' background characteristics were related to mental health 30 years after repatriation. Pless Kaiser et al. examine current health among women veterans in relation to warzone stress, and considered whether posttraumatic stress disorder symptoms mediated the effects of warzone stress on mental and physical health. In contrast, Jahn et al. examine a diverse group of veterans, drawing on theories of posttraumatic growth to explore whether the combination of combat exposure and posttraumatic stress disorder in early life affect coping with cancer in later life. Finally, Settersten, Jr., et al. examine how World War II vete...
The preparation and antioxidant activity of BHA bonded to porous glass

Butylated hydroxyanisole (BHA) has been bonded to porous glass beads, thus utilizing its functional characteristics while preventing it from entering the final food products. The glass-bonded BHA has been tested in lard and found to have only one percent of the free BHA activity, which can be attributed to stereochemical shielding effects. Evidence is presented strongly indicating that the observed activity resulted from BHA bonded to glass, although activity resulting from BHA leached from the glass could not be conclusively ruled out.
Effect of chronic p,p'-dichlorodiphenyldichloroethylene (DDE) exposure on high fat diet-induced alterations in glucose and lipid metabolism in male C57BL/6H mice

Diabetes mellitus is a highly prevalent metabolic disease affecting 29.1 million people or 9.3% of the population of the United States. The most prevalent form of diabetes is type 2 diabetes (T2D) which comprises 90-95% of all reported cases of diabetes. While the exact cause of T2D remains an enigma, known risk factors include age, weight, sedentary lifestyle, poor dietary habits, and genetic predisposition. However, these risk factors can not sufficiently explain the increasing prevalence of T2D. Recently, environmental exposures have been explored as potential risk factors. Indeed, epidemiological and limited empirical studies have revealed elevated serum concentrations of certain persistent organic pollutants (POPs), including the bioaccumulative metabolite of p,p'-dichlorodiphenyltrichloroethane (DDT), p,p'-dichlorodiphenyldichloroethylene (DDE), are positively correlated with increased T2D prevalence. The goal of the present study is to determine if chronic exposure to DDE promotes T2D in a widely used in vivo model, the high saturated fat-fed mouse. Male C57BL/6H mice were exposed to DDE (2.0mg/kg) or vehicle (corn oil; 1ml/kg) via gavage for 5 consecutive days, then every 7 days for the duration of the study. One week following the 5 day consecutive DDE dosing, animals were placed on either a low fat (10%kcal from lard) or high fat (45%kcal from lard) diet (HFD) for 13 weeks. Chronic exposure to DDE promoted fasting hyperglycemia after 4 and 8 weeks on the HFD diet and normalized fasting blood glucose levels at week 13. This DDE-mediated decrease in fasting hyperglycemia was preceded by improved glucose tolerance at week 12. In addition to normalizing fasting hyperglycemia at the end of high fat feeding, DDE exposure decreased HFD-induced fasting hyperinsulinemia, homeostasis model assessment of insulin resistance (HOMA-IR) values, and hepatic steatosis. Therefore, based on the current data, chronic DDE exposure appears to have a biphasic effect on HFD-induced hyperglycemia in the male C57BL/6H mouse characterized by elevated fasting blood glucose at weeks 4 and 8 of HFD intake followed by normoglycemia upon sacrifice. In addition, chronic DDE exposure reduced HFD-induced hepatic steatosis upon sacrifice. These results indicate chronic exposure to DDE can directly affect systemic glucose and hepatic lipid metabolism and that these effects can be diet dependent.
Human-computer communications with special reference to technological developments, occupational stress and educational needs.

The rapid development of computer technology is reviewed and its impact on employment and on the gross national product is mentioned. The process of designing an effective human-computer communication system is outlined, the role of job satisfaction is mentioned and methods which can be utilized to minimize (or optimize) occupational stress in human-computer communication work environment is discussed. The impact of utilizing high technology on the educational needs of ergonomists are outlined.
Unsteady flow interactions between a pair of advected vortex tubes and a rigid sphere

Abstract An idealized representation of the interaction of spherical particles with turbulent eddies of comparable length scale is considered by means of a three-dimensional, unsteady finite-difference Navier-Stokes solution of the interaction between a fixed rigid sphere and a pair of advecting vortex tubes. Initially the sphere is suddenly placed in the flow and held fixed in space. First, a doubly symmetric interaction with vortices of opposite rotation is considered. The resulting time-dependent drag differs from the drag in axisymmetric flows; however, the lift and torque on the sphere remain zero. Next, an interaction with two vortices of like rotation is studied. Here, non-zero lift and torque, as well as drag deviation from the axisymmetric case occur and would result in a deflection in the trajectory of a nonfixed sphere. The flow in this case behaves like that of a single vortex. Finally, a linear array of like-rotating vortices, interacting with a freely moving sphere, is considered. The two-dimensional deflection depends strongly upon the sphere/fluid density ratio and initial sphere Reynolds number. Lift and moment coefficients are shown to be linearly proportional to the maximum induced velocity due to the vortices. Moment coefficients are an order of magnitude less than lift coefficients.
Low Crossover of Methanol and Water Through Thin Membranes in Direct Methanol Fuel Cells

Low crossover of both methanol and water through a polymer membrane in a direct methanol fuel cell (DMFC) is essential for using high concentration methanol in portable power applications. A novel design of the membrane-electrolyte assembly (MEA) has been developed in this work to attain low methanol crossover, low water crossover, and high cell performance simultaneously. The anode catalyst layer, in the form of a catalyzed diffusion medium (CDM), serves as a methanol diffusion barrier to reduce methanol crossover. In addition, a highly hydrophobic cathode microporous layer (MPL) is employed to build up the hydraulic pressure at the cathode and hence drive the product water from the cathode into the anode to offset the water dragged by electro-osmosis. The new MEA, consisting of a CDM anode, a thin Nafion membrane, and a carbon cloth precoated with an MPL on the cathode, is shown to attain: (i) a net water transport coefficient through the membrane smaller than 0.8 at 60°C and 0.4 at 50°C; (ii) fuel efficiency of ∼80%; and (iii) a steady-state power density of 60 mW/cm 2 at ca. 0.4V and 60°C with low stoichiometric flow rates of ambient dry air and 3 M methanol solution.
Fully wireless implementation of distributed beamforming on a software-defined radio platform

ABSTRACT We describe the key ideas behind our implementation of distributed beamforming on a GNU-radio based software-defined radio platform. Distributed beamforming is a cooperative transmission scheme whereby a number of nodes in a wireless network organize themselves into a virtual antenna array and focus their transmission in the direction of the intended receiver, potentially achieving orders of magnitude improvements in energy efficiency. This technique has been extensively studied over the past decade and its practical feasibility has been demonstrated in multiple experimental prototypes. Our contributions in the work reported in this paper are three-fold: (a) the first ever all-wireless implementation of distributed beamforming without any secondary wired channels for clock distribution or channel feedback, (b) a novel digital baseband approach to synchronization of high frequency RF signals that requires no hardware mod-ifications, and (c) an implementation of distributed beam-forming on a standard, open platform that allows easy reuse and extension. We describe the design of our system in de-tail present some initial results and discuss future directions for this work.
Breakout Session Report: Lubricants, Overcoats and Surface Modification Techniques

This group consisted of scientists and engineers with diverse training and from varied working environments. There was a good mix of scientists and engineers, tribologists and MEMS specialists, and researchers from universities, industry and government laboratories. As a result, the discussion ranged widely. Discussion in the afternoon session returned to some of the topics highlighted in the morning, e.g., stiction and characterization, but with the addition of new opinions provided by a number of newcomers to the session.
Effect of Rancidity on the Feeding Value of Rice Bran for Chickens

Abstract Rice bran that was allowed to become rancid and was fed to chicks at 60% of the diet reduced growth more than fresh rice bran or a stored sample in which rancidity was retarded by the addition of ethylenediaminetetraacetate (EDTA). The EDTA had no effect on rice bran that was already rancid or in which the lipase activity had been destroyed by autoclaving. There was no significant difference in the taste of the thigh or skin samples of fryers fed stock mash or the diets in which the rice bran was fresh, rancid, or stored with EDTA added. Thiobarbituric acid reactive compounds were also similar in the fat of the skin and adipose tissue of these birds. Metabolizable energy values of fresh and rancid rice bran were similar as determined with adult male chickens.