cssi/SciSciGPT-SciSciNet huggingface dataset:
On predicting forming limits using hill’s yield criteria

The analysis of localized necking is strongly dependent on the yield function. To predict forming limits, therefore, numerous yield criteria have been postulated to characterize the plastic deformation of sheet materials. Among them Hill’s 1948 and the fourth form of 1979 yield criteria are the most commonly used. A new yield criterion was proposed by Hill in 1993. It uses five independent and easily obtainable material parameters, which makes it flexible in representing the shape of the yield locus for different materials. The present investigation compares these three yield criteria in forming limit predictions based on both the Marciniak and Kuczynski (M-K) approach and the bifurcation analysis. It is observed that the M-K analysis based on Hill’s 1993 yield criterion provides forming limit predictions in agreement with experimental data. The bifurcation analysis based on Hill’s 1948 yield criterion also provides an acceptable prediction of forming limits for aluminum, although they are slightly higher. All three yield criteria are found to provide acceptable predictions for aluminum-killed (AK) steel based on the M-K method. For brass, only the prediction based on the M-K method and Hill’s 1993 yield criterion is close to the trend of experimental data.
A cooperative breeding programme for the Mongolian wild horse Equus przewalskii in the United States

Abstract The Mongolian wild horse Equus przewalskii (Poliakov, 1881) has been propagated in captivity for ten generations. Well over a decade has passed since the last confirmed sightings of E. przewalskii in its historic range. Concern over the extent of inbreeding which has occurred during the captive propagation of this endangered species has led to numerous recommendations for management of captive stock as genetic populations rather than isolated collections. In November 1979 a meeting was held of North American Przewalski's horse breeders, at which time a coordinated breeding programme was considered and adopted by all institutions breeding E. przewalskii in the United States. As a result of this agreement, a number of animal movements between zoos have occurred with a projected decrease in the extent of inbreeding of foals of the next generation. The history of propagation of E. przewalskii in the United States and the genetic considerations involved in the management programme are discussed.
An implementation of structured walk-throughs in teaching Cobol programming

The effectiveness of structured walk-throughs in teaching introductory Cobol programming was empirically assessed with a sample of 215 undergraduate business administration majors. Cobol proficiency was measured by a final examination testing (a) knowledge of language rules, (b) ability to read and debug a program, and (c) the ability to write a program. Analysis of multiple covariance was used to statistically adjust test scores for age and conditional reasoning scores.The findings provide empirical support for incorporating structured walk-throughs into the programming learning process to more effectively develop student proficiency in writing Cobol programs.
The generation and maintenance of diversity in microbial communities

Microorganisms play a central role in the regulation of ecosystem processes, and they comprise the vast majority of species on Earth. With recent developments in molecular methods, it has become tractable to quantify the extent of microbial diversity in natural environments. Here we examine this revolution in our understanding of microbial diversity, and we explore the factors that contribute to the seemingly astounding numbers of microbial taxa found within individual environmental samples. We conducted a meta-analysis of bacterial richness estimates from a variety of ecosystems. Nearly all environments contained hundreds to thousands of bacterial taxa, and richness levels increased with the number of individuals in a sample, a pattern consistent with those reported for nonmicrobial taxa. A cursory comparison might suggest that bacterial richness far exceeds the richness levels typically observed for plant and animal taxa. However, the apparent diversity of bacterial communities is infl uenced by phylogenetic breadth and allometric scaling issues. When these features are taken into consideration, the levels of microbial diversity may appear less astounding. Although the fi elds of ecology and biogeography have traditionally ignored microorganisms, there are no longer valid excuses for neglecting microorganisms in surveys of biodiversity. Many of the concepts developed to explain plant and animal diversity patterns can also be applied to microorganisms once we reconcile the scale of our analyses to the scale of the organisms being observed. Furthermore, knowledge from microbial systems may provide insight into the mechanisms that generate and maintain species richness in nonmicrobial systems.
Design considerations for effective control of an afterburner sub-system in a combined heat and power (CHP) fuel cell system (FCS)

This article investigates various control strategies for a combined heat and power (CHP) fuel cell system (FCS), with a specific focus on the afterburner sub-system. The afterburner sub-system recovers heat and by-products from the excess fuel and oxidant not consumed within the fuel cell. The overall performance of a CHP FCS depends crucially on the control of the afterburner sub-system because the control of this sub-system (1) determines the extent of thermal energy recovered from the system, between 35 and 55% of fuel energy input; (2) establishes the rate limiting step in the control of the overall CHP FCS because the rate at which the afterburner can combust excess fuel and oxidant safely and raise steam affects the rate at which the fuel cell’s electrical power output can change; and (3) impacts upstream mass and energy flows strongly, such as the system’s overall water balance and also the raising of steam for the upstream fuel processor and cathode humidification, as this is the point in the system where the CHP FCS becomes closed loop for heat and mass flows. Using an Aspen Plus® chemical engineering model of the CHP FCS, this article (1) identifies potential challenges in operating the afterburner sub-system, (2) discusses various options for ameliorating those challenges, and (3) recommends viable solutions. The two challenges it discusses in detail are (1) the danger of overheating the afterburner, and (2) the danger of overheating a downstream steam generator. Regarding the first challenge, in the low anode hydrogen utilization (AHU) range (66–85%) specified by some fuel cell manufacturers, the afterburner is in danger of overheating beyond its maximum rated operating point. Regarding the second challenge, also at low anode hydrogen utilizations, the steam generator is in danger of overheating beyond its maximum rated operating point. This article demonstrates that one solution for overcoming these challenges is to dilute the afterburner’s stream with exhaust gas from the cathode. This article shows the ratio of cathode exhaust flow rates that achieve the desired operating temperature regions for the afterburner and downstream sub-system components. Using this method, this article determines an optimal control strategy solution for the afterburner sub-system.
Power dissipation in slow light devices: a comparative analysis

The performance of various slow light schemes is analyzed from the point of view of power dissipation per stored bit. It is shown that the dissipated power increases quite nonlinearly with storage capacity, and that the schemes based on low-loss photonic structures with distributed amplifiers hold indisputable advantage over other schemes.
Utilization of polymer viscoelastic properties in acoustic wave sensor applications

Acoustic wave responses arising from changing viscoelastic properties of polymer film overlays are investigated when induced by a photo-cross-linking reaction and vapor absorption. When a polymer film is present on the surface of an acoustic wave device, changes in the viscoelastic properties of the film induce changes in wave propagation velocity and attenuation, providing two sensor responses. Film changes which occur during polymer cross-linking allow photopolymerization to be monitored in real time using acoustic devices. A photoaction spectrum of photoresist reveals the cross-linking wavelength with maximum quantum yield. Changes in the viscoelastic properties of a polysiloxane film induced by vapor absorption are found to be unique for each of several species, making differentiation of species with a single film possible. A Maxwell model for polymer viscoelasticity, in combination with mass loading effects, provides a sound theoretical basis for explaining observed results for both polysiloxane and polybutadiene/polystyrene copolymer films. >
Correlation of sonographic measurements of the internal jugular vein with central venous pressure

Determination of volume status is crucial in treating acutely ill patients. This study examined bedside ultrasonography of the internal jugular vein (IJV) to predict central venous pressure (CVP). Ultrasonography was performed on 34 nonventilated patients with monitored CVPs. The IJV was measured during the respiratory cycle and with the patient in different positions. Mean IJV diameter in patients with CVP less than 10 cm H2O was 7.0 mm (95% confidence interval [CI], 5.7-8.3) vs 12.5 mm (95% CI, 11.2-13.8) in patients with CVP of 10 cm H2O and greater. Measurement of end expiratory diameter with the patient supine had the highest correlation coefficient: 0.82 (95% CI). There was strong agreement among ultrasonographers: correlation coefficient, 0.92 (95% CI). This pilot study shows promise that ultrasonography of the IJV can be a noninvasive tool to predict CVP. Measurement of end expiratory diameter in supine patients exhibited a high correlation to CVP.
Event-mapping tasks: investigating the effects of prior information and event complexity on performance

Infants younger than 11.5 months typically fail in event-mapping tasks with complex event sequences, yet succeed when the event sequences are made very simple and brief. The present research explored whether younger infants might succeed at mapping complex event sequences if infants were given information to help them organize and structure the event. Three experiments were conducted with 7.5-month-olds. In all of the experiments, the infants were shown a two-phase test event. In the first phase, infants saw a box–ball occlusion sequence in which the objects emerged at least once to each side of the screen, reversing direction each time to return behind the screen. In the second phase, infants saw a one-ball display. Prior to the test trials, infants were shown an “outline” of the test event that contained the basic components of the event. The experiments varied in (a) the kind of information included in the event outline and (b) the complexity of the box–ball test sequence (i.e., the number of object reversals). The results revealed that the 7.5-month-olds benefitted from viewing an event outline, although the performance of the males was more robust than the females. These results add to a growing body of research indicating that young infants can succeed on event-mapping tasks under more supportive conditions and provide insight into why event mapping is such a difficult task for young infants.
Pseudo-Derivative Feedback Control

The extensive presence of simple PID controllers all over the process and manufacturing industries attests to their continuing and lasting effectiveness in dealing with all but the most complex and demanding industrial control problem. Problems do arise with PID controllers however. In particular high frequency sensor noise problems can become severe in some applications, due to the presense of the D component of the PID controller. By altering the controller structure slightly, it is possible to obtain the attendant benefits of derivative action, without taking the derivative of the error function. This is called pseudo-derivative feedback and overcomes many of the major problems of derivative control. The structure and ramifications of this scheme is examined here, for both multivariable and single input single output systems.
Effects of hydrogen on the fracture morphology of Inconel 718

Abstract Many materials display a tendency to embrittle when subjected to a hydrogen environment. This behavior is extremely material specific and there is no reliable method for the prediction of embrittlement in previously untested materials. It is therefore necessary to experimentally determine the effects of hydrogen on materials which may experience such an environment during their service life. Inconel 718 has many applications in the aerospace industry and as a result may encounter a high partial pressure hydrogen environment. In this study, fractured Inconcel 718 tensile samples were examined in a scanning electron microscope to determine the effects of atmosphere on their fracture surfaces. Two base metal and two weld specimens were examined, one of each tested in 6.9 MPa helium or hydrogen atmospheres at room temperature. No evidence of embrittlement was noted for the base metal samples, while the weld samples were slightly embrittled. The effect was minor, however and the fracture mode in all four cases was ductile microvoid coalescence.
Non-contaminating method to reduce Marangoni convection in microgravity float zones

A ground-based experiment has validated the effectiveness of a noncontaminating method developed to reduce Marangoni (thermal capillary) convection in float-zone processing of corrosive materials in space microgravity. A drop of silicone oil 1.5 mm high was enclosed in a transparent box, and the small size of the drop was shown to suppress the 1-g thermal-buoyant convection. A vertical jet of air was blown tangentially over a vertical free surface, producing a viscous shear drag which opposes the Marangoni surface shear. A 66 percent reduction in Marangoni velocities was found in the lowest one-third of the drop, corresponding to the resolidification surface in a float-zone melt.
TURBULENT FLOW AND HEAT TRANSFER IN STAGGERED TUBE BANKS WITH DISPLACED TUBE ROWS

Abstract Turbulent flow in closely spaced staggered tube bundles is numerically investigated using a finite volume approach in general curvilinear coordinates. Attention is focused on the hydrodynamic and thermal effects of the longitudinal displacement of alternate tube rows. The computations used both standard and two-layer k-∊ turbulence models in conjunction with a streamwise periodic finite volume formulation. The computations are in excellent agreement with experimental data for the limiting case of flow and heat transfer in undisplaced tube banks. Furthermore, the results indicate increases in both pressure drop and heat transfer with an increase in displacement. The results of this study may serve as an aid in the design of shell and tube cross-flow heat exchangers.
Heteroepitaxial processes at low and elevated pressures

Based on design criteria established in preceding work for conditions of moderately elevated pressure (less than or equal to 8 bar) we have designed and evaluated a reactor for chemical vapor deposition (CVD) at high pressure (less than or equal to 100 bar). While at moderate pressure non-turbulent unidirectional forced channel flow past a heated substrate wafer can be realized, at high pressure, the flow is expected to become turbulent. Due to phase front distortions and variations in angle of incidence associated with density fluctuations and density gradients in the high pressure vapor phase in the vicinity of the hot substrate -- the precision of methods of real-time optical process monitoring that employ polarized light, such as, p-polarized reflectance spectroscopy (PRS), is degraded. Above a critical pressure, features in the optical signals related to chemical kinetics and to the kinetics of heteroepitaxy, thus are no longer resolved. Therefore, experimentation at reduced gravity, which extends the pressure range of non-turbulent flow, and alternative robust methods of real-time optical process monitoring are considered. At very high pressures, where real-time process monitoring is severely curtailed, CVD processing must rely on predictions of numerical models -- validated by experimentation at lower pressure/low gravity. Experimentation at high pressure is needed to access materials, properties and/or structures that otherwise cannot be realized.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
A physics-based, small-signal model for graphene field effect transistors

Abstract In this letter, a small-signal model for the graphene-based field effect transistor based on a physical description of the device’s operation is presented. The small-signal model contains circuit elements similar to classical small-signal models for field effect transistors but these elements differ vastly in their behavior with bias, owing to the different physical behavior of these devices. Intrinsic and extrinsic small-signal models are presented. The high-frequency performance of the models in terms of short-circuit current gain and Mason’s unilateral gain, and associated frequency figures-of-merit, are examined.
Hemostatic agent microporous polysaccharide hemospheres (MPH) does not affect healing or intact sinus mucosa.

Objectives/Hypothesis: Absorbable hemostatic agents are used routinely following sinus surgery. Recent studies suggest that current biomaterials, such as FloSeal Matrix Hemostatic Sealant (Fusion Medical Technologies, Mountain View, CA) may interfere with mucosal regeneration. This study was designed to evaluate the effects of Microporous Polysaccharide Hemospheres (MPH, Medafor, Inc., Minneapolis, MN), a novel rapidly-absorbing hemostatic powder, on healing and intact sinus mucosa. Study Design: Prospective, controlled study using the rabbit model. Methods: Both maxillary sinuses of 14 New Zealand white rabbits were surgically opened. The mucosa of 10 rabbits were stripped bilaterally, and the left sinus of each was then treated with either MPH or FloSeal. The mucosa of four additional rabbits were incised but otherwise remained undisturbed. Again, the left sinus of each of the four additional rabbits was treated with either MPH or FloSeal. The right sinus served as an untreated control (stripped or intact) in both arms of the study. Animals were recovered and euthanized 2 weeks later. Specimens were examined by a blinded pathologist using light microscopy. Results: Untreated regenerated mucosa showed expected areas of sparse cilia, mild serous gland reduction, and fibrosis. MPH-treated sinuses showed no significant changes compared to respective controls, and no MPH substance was identified. In contrast, regenerating mucosa treated with FloSeal showed extensive loss of cilia, inflammation, and fibrosis. Residual FloSeal particles were present within the sinus cavity and grossly incorporated within healing mucosa. Unexpectedly, intact mucosa exposed to FloSeal showed similar findings. Conclusions: Absorbable hemostatic materials have starkly different effects on mucosal healing. Unlike other agents, MPH is rapidly cleared and has no negative effects on healing or intact sinus mucosa.
Social Feedback Influences Musically Induced Emotions

Numerous studies have shown that music is a powerful means to induce emotions. The present study investigates whether these emotional effects can be manipulated by social feedback. In an Internet-based study, 3315 participants were randomly assigned to two groups and they listened to different music excerpts. After each excerpt, participants rated emotions according to arousal and valence dimensions. Additionally, those in group 2 received feedback allegedly based on the emotional ratings of preceding participants. Results show that feedback significantly influenced participants' ratings of group 2 in the manipulated direction compared to the group without feedback.
Cellular automata to application: Information processing in cellular automata

Cellular automata (CA) are discrete dynamic systems governed by local and usually deterministic state transition rules. These systems are computational in that their macroscopic behavior computes some n-dimensional spatial function over time. The entropy or information of such systems is a passive result of their global behavior but has no impact on their ongoing dynamics. The processes underlying intelligence, however, involve what is generally termed information processing. An important aspect of these processes is the modulation of system dynamics by some function of the information content of the state vector. Consequently, CA, as usually formulated, are not information processing systems. This paper presents systems of CA which are capable of information processing because their dynamics are governed by both local transitional rules and global information variables.
Preliminary results from a study of the double beta decay of 150Nd

We report the preliminary results from a study of the double beta decay of 150 Nd to the first 0 + excited state of 150 Sm. Our data consists of 50 days of counting 5 kg of natural Nd 2 O 3 at the LBNL-Oroville low background facility. The deduced lower limit for the half life of this decay mode is 4.9 × 10 19 years.
Dual mobility acetabular components for revision THA

Recurrent instability after primary and revision total hip arthroplasty (THA) is a disastrous complication for the surgeon and the patient. Dislocation after revision total hip arthroplasty has been reported to be as high as 20 % in some series [1]. Patients who suffer from recurrent dislocations are challenging because historical treatment options, including constrained liners, have had disappointing results [2]. Dual mobility acetabular cups were initially introduced to reduce dislocation rates after primary total hip arthoplasty [3]. While dual mobility acetabular components have been shown to improve stability in primary THA, few studies have examined the outcomes of dual mobility bearings in revision THA for persistent dislocation [4]. The current study by van Heumen et al. [5] was a retrospective cohort study with 49 consecutive patients (50 hips) that underwent an isolated acetabular revision with a dual mobility cup (Avantage; Biomet, Warsaw, IN, USA) for recurrent instability with an average follow-up of 29 months (12–66 months) [3]. The cohort of patients was challenging, as 30 patients (60 %) had more than two surgeries. However, despite a challenging cohort of patients, no post-operative dislocations occurred during follow-up period; however, three hips were revised, most commonly for infection. Overall, the survival rate for dislocation after 56 months was 100 % and 93 % for all cause revision. Although this study does not have long-term follow-up results or any functional outcome data, it does demonstrate excellent 5 year survival rate with a dual mobility cup in revision THA for recurrent instability. While I commonly use dual mobility bearings for patients with a high risk of dislocation and for revisions for recurrent instability, my personal results have been less impressive than van Heuman et al. and Mohammed et al. In this challenging group of patients, I have seen patients who still suffer from recurrent dislocations, despite using a dual mobility bearing. I also have seen intraprosthetic dissociation, particularly using smaller head sizes (e.g., 22 mm) and when the implant company of the femur differs from the implant company of the dual mobility acetabular component. Still, the current study highlights that a dual mobility bearing may be a great option for patients who require revision for recurrent instability. However, it goes without saying that this remains a very challenging group of patients, and using a dual mobility bearing seems to improve the risk of dislocation compared to historical treatment options but the risk is not entirely eliminated.
Job conditions, unmet expectations, and burnout in public child welfare workers: How different from other social workers?

Abstract The purpose of this research is to compare public child welfare workers' perception of job conditions, unmet expectations, and burnout to those of social workers in other settings. Using data from a sample of 408 social workers identified from a cross-sectional random survey of California registered social workers, a series of ANOVA and multiple regression analysis was performed. Results of ANOVA revealed that public child welfare workers experienced higher workloads, greater role conflict, and depersonalization, and had lower personal accomplishment. However, they had similar levels of unmet expectations and emotional exhaustion as other social workers. Adjusted for perceived job conditions and demographic characteristics, regression analyses revealed that public child welfare workers had significantly higher levels of depersonalization than those of private child welfare workers. Finally, workers in public settings exhibited significantly lower levels of personal accomplishment than social workers in private settings did, regardless of their practice field. Implications for organizational practices and future research are discussed.
Current Obstetrical Practice and Umbilical Cord Prolapse

The aim of this study was to assess the contribution of current obstetrical practice to the occurrence and complications of umbilical cord prolapse. Maternal and neonatal charts of 87 pregnancies complicated by true umbilical cord prolapse during a 5-year period were reviewed. Twin gestation and noncephalic presentations were common features (14 and 41%, respectively). Eighty-nine percent (77) of infants were delivered by cesarean section of which 29% were classical and 88% were primary. The mean gestational age at delivery was 34.0 +/- 6.0 weeks, and the mean birth weight was 2318 +/- 1159 g. Obstetrical intervention preceded 41 (47%) cases (the obstetrical intervention group): amniotomy (9), scalp electrode application (4), intrauterine pressure catheter insertion (6), attempted external cephalic version (7), expectant management of preterm premature rupture of membranes (14), manual rotation of the fetal head (1), and amnioreduction (1). There were 11 perinatal deaths. Thirty-three percent of the infants (32) had a 5-min Apgar score < 7 and 34% had a cord pH < 7.20. Neonatal seizures, intracerebral hemorrhage, necrotizing enterocolitis, hyaline membrane disease, persistent fetal circulation, sepsis, assisted ventilation, and perinatal mortality were comparable in the "obstetrical intervention" and "no-intervention" groups. Most of the neonatal complications occurred in infants < 32 weeks' gestation. We conclude that obstetrical intervention contributes to 47% of umbilical cord prolapse cases; however, it does not increase the associated perinatal morbidity and mortality.
An international standard for electroretinography.

An international standard procedure for electroretinography (ERG) has finally been established. It represents a minimum protocol to record five basic signals (rod response, scotopic maximal response, oscillatory potentials, single-flash cone response, 30-Hz flicker response). Individual laboratories may continue to do additional or specialized procedures, but the hope is that all laboratories will include “standard” responses in their routine protocols so ERG data can be compared throughout the world for patient care and for research.
Macroscopic characterisation of a two-fluid anisotropic warm plasma

Two `compressivity tensors' are suggested, which, together with the permittivity tensor and the permeability, with characterise the macroscopic electromagnetic properties of an anisotropic warm plasma under the two-fluid model. A new set of four governing equations is formulated, which is both mathemathematically concise and amenable to meaningful physical interpretation.
Generalizations of Young’s Theorem to real functions of several variables

In 1907 W. H. Young classified the real-valued Baire one functions on the line which have the Darboux (intermediate-value) property as those which are bilaterally approachable. Here we investigate generalizations of this theorem to the setting of real-valued Baire one functions of several variables which possess various “Darboux-like” properties.
Catholic and protestant social discourse and the American welfare state

John Tropman (1986, 1995), among others, develops the notion of a Catholic ethic which he juxtaposes to the more traditional (at least in America) notion of the Protestant ethic as theorized by Max Weber (1905). Using his work and discourse analysis as our starting points, we attempt to construct our own complimentary conception of the Catholic ethic through a series of readings of historical documents and make a case for comprehending the general tone and direction of the discourse on the American welfare state during the New Deal and Great Society eras under the idiomatic rubric of this ethic. Subsequently, we will make the case for understanding the social and political discourse surrounding the proposal and passage of TANF in light of the more traditional Protestant ethic. The ultimate goal of the work is to re-frame the welfare debate in America as a struggle not just between competing methods of problem solving, but, more importantly, as a paradigmatic competition between two divergent aspirants for political-cultural hegemony in the arena of American social discourse.
eBay as the “Terminator”: Determining User Suspension From Feedback Ratings

Good reputations are won and lost by individuals and companies in various forms on the Internet. eBay has the earliest and most well-known formal ecommerce reputation system and “terminates” members who do not play by the rules. We examine a dataset of 102,035 Not-A-Registered-User (NARU) eBay account feedback ratings from eight different countries. Careful investigation of feedback density over time reveals that threshold values for termination can be detected from feedback history. Several modeling approaches are studied and the Local Polynomial Regression Model (LPRM) is chosen for analysis because it is data driven and no prespecified parametric functional form is assumed. Analyzing US data, we find that large-volume sellers have a higher overall negative feedback compared to those of medium volume sellers. We use the second derivative of the LPRM to explicitly determine the threshold points, that is, the point where a seller's negative feedback increases significantly. These thresholds vary from as m...
Informed Consent in Endoscopic Sinus Surgery: The Patient Perspective

Objectives: To understand patient expectations during the informed consent process for functional endoscopic sinus surgery (FESS). Study Design: Multi-institutional, cross-sectional survey design. Methods: Anonymous surveys were administered to patients in two tertiary academic centers with a chief complaint relating to “allergy and sinus” problems. Patients completed an eight-item questionnaire that assessed both the nature and the level of risks that they wished to be informed of prior to FESS. Results: Three hundred eighty-nine surveys were returned. Sixty-nine percent of patients wished to be informed of complications that occur as infrequently as 1 in 100 cases, regardless of severity. Ninety percent of patients wanted to know of a risk that occurred as frequently as 1 in 10 cases. Patients also reported whether or not they wished to be told in detail about specific complications during the informed consent process, regardless of their infrequency. Affirmative responses were as follows: 83% for cerebrospinal fluid leak and orbital injury, 81% for infection, 76% for revision surgery, 74% for impairment of smell, 73% for bleeding and myocardial infarction, 72% for cerebrovascular accident, and 58% for scarring. Conclusions: Patients wanted to be informed about severe FESS complications at a higher rate than physicians previously surveyed, even if the incidence is low. This study, combined with our previous examination of the physicians' perspective, highlights that there may be a discrepancy between what the physician and the patient believe are priority topics during the informed consent process.
The role of acculturative stress factors on mental health and help-seeking behavior of sub-Saharan African immigrants

African immigrants to the United States are largely increasing in number. However, African immigrants' psychological health and help-seeking behavior remain understudied. J.W. Berry's acculturation theories suggest that immigrants' mental health can be negatively affected by their experience of biological and psychosocial difficulties related to acculturation. Data from a nationally representative study, the New Immigrant Survey, was utilized to examine how acculturation stress factors can predict depressive symptoms in a sub-Saharan African sample of 669 adults. The collectivistic nature of African culture suggests that family support is a critical element in the acculturation process, but family support was not found to be a predictor of help-seeking behavior. Results indicated that when birth country was controlled for, proficient English language skills and higher education level were predictive of increased help-seeking behavior. Additionally, English language proficiency was negatively associated wi...
Population decline induced by gonorrhoea and tuberculosis transmission: Micronesia during the Japanese occupation, 1919–45

The islands of Yap in Micronesia survived a period of severe depopulation during the Japanese occupation from 1919 to 1945. Using data from historical documents, supplemented by ethnographic evidence, we calibrate a simulation model that accounts for this phenomenon. Our model tracks the reproduction histories of a synthetic cohort of women in Yap, including effects of infertility due to gonorrhoea as well as tuberculosis mortality, and predicts the net reproduction rate (NRR). In this particular case and throughout history, human migrations and associated social and cultural interactions have frequently been accompanied by dramatic changes in patterns of disease transmission and substantial demographic consequences. Despite the broad emphasis on mortality as a measure of demographic consequences in the historical and contemporary literature, there are important instances where life expectancy at birth, fertility rates, and total population size are important demographic consequences. We find that gonorrhoea may have significantly contributed to depopulation during the Japanese occupation of Micronesia, due to repeated infections and high risk of sterility. Results of our model suggest that gonorrhoea alone could have reduced the net reproduction rate by 82%, whereas deaths from tuberculosis may have contributed to a 17% decline.
An analysis of biofeedback training effects for tension headache patients

Six tension headache patients were provided feedback training for control of frontalis muscle activity. Electromyogram responses were measured in baseline, feedback, and self-management phases in each of 16 treatment sessions. Self-reports of headaches were obtained four times daily throughout pretreatment, treatment, and follow-up periods. Self-reports were also obtained concurrent with electromyogram measures in the laboratory. The laboratory data show no maintained self-control of muscle activity, and reveal a discrepancy between direction of change of muscle activity and reports of headache intensity. However, the extra-laboratory results indicate changes in self-reports of headaches for three of the six subjects. The discrepancy between the laboratory and extra-laboratory results were discussed.
Commuter Students, Online Services, and Online Communities

This chapter reviews student services and community-building initiatives aimed at serving commuter students online.
Optimum design of a gearbox for low vibration

A computer program was developed for designing a low vibration gearbox. The code is based on a finite element shell analysis, a modal analysis, and a structural optimization method. In the finite element analysis, a triangular shell element with 18 degrees-of-freedom is used. In the optimization method, the overall vibration energy of the gearbox is used as the objective function and is minimized at the exciting frequency by varying the finite element thickness. Modal analysis is used to derive the sensitivity of the vibration energy with respect to the design variable. The sensitivity is representative of both eigenvalues and eigenvectors. The optimum value is computed by the gradient projection method and a unidimensional search procedure under the constraint condition of constant weight. The computer code is applied to a design problem derived from an experimental gearbox in use at the NASA Lewis Research Center. The top plate and two side plates of the gearbox are redesigned and the contribution of each surface to the total vibration is determined. Results show that optimization of the top plate alone is effective in reducing total gearbox vibration.
Application of the time varying transfer function for exact small-signal analysis

An analysis method for determining the control-to-output linearized describing function of time-interval-modulated switched networks using time-varying system theory was previously proposed by the author. A simplification is now presented which eases the analysis considerably. Use of the simplified approach is demonstrated in the derivation of the control-to-output frequency response of pulse-width-modulated (PWM) DC-to-DC switching power converters operating in discontinuous conduction mode (DCM) and current programmed converters operating in continuous conduction mode (CCM) as well as in DCM. Experimental results are presented which verify the modeling approach. >
A model of heat transfer in sapwood and implications for sap flux density measurements using thermal dissipation probes

A variety of thermal approaches are used to estimate sap flux density in stems of woody plants. Models have proved valuable tools for interpreting the behavior of heat pulse, heat balance and heat field deformation techniques, but have seldom been used to describe heat transfer dynamics for the heat dissipation method. Therefore, to better understand the behavior of heat dissipation probes, a model was developed that takes into account the thermal properties of wood, the physical dimensions and thermal characteristics of the probes, and the conductive and convective heat transfer that occurs due to water flow in the sapwood. Probes were simulated as aluminum tubes 20 mm in length and 2 mm in diameter, whereas sapwood, heartwood and bark each had a density and water fraction that determined their thermal properties. Base simulations assumed a constant sap flux density with sapwood depth and no wounding or physical disruption of xylem beyond the 2 mm diameter hole drilled for probe installation. Simulations across a range of sap flux densities showed that the dimensionless quantity k [defined as (ΔT(m) -ΔT)/ΔT, where ΔT(m) is the temperature differential (ΔT) between the heated and unheated probe under zero-flow conditions] was dependent on the thermal conductivity of the sapwood. The relationship between sap flux density and k was also sensitive to radial gradients in sap flux density and to xylem disruption near the probe. Monte Carlo analysis in which 1000 simulations were conducted while simultaneously varying thermal conductivity and wound diameter revealed that sap flux density and k showed considerable departure from the original calibration equation used with this technique. The departure was greatest for variation in sap flux density typical of ring-porous species. Depending on the specific combination of thermal conductivity and wound diameter, use of the original calibration equation resulted in an 81% under- to 48% overestimation of sap flux density at modest flux rates. Future studies should verify these simulations and assess their utility in estimating sap flux density for this widely used technique.
High-speed memory scan as a retention interval activity in short-term memory

A Sternberg high-speed memory scan task was used as a retention interval activity in a standard Brown-Peterson paradigm. Two levels of Sternberg search set, one or five items, were employed to see if the differential memory load produced by the different size search sets resulted in differential recall in the Brown-Peterson task. A comparison was made to a control condition in which S was required to shadow digits during the retention interval. No differential effect on recall of memory load was found when the Sternberg tasks were compared across three different retention intervals. Very little forgetting was produced by the Sternberg tasks as compared to the digit shadowing condition. Results are discussed in terms of the need for verbal activity to prevent rehearsal in short-term memory.
3D mesh compression using an efficient neighborhood-based segmentation

3D mesh compression and segmentation are two active areas of 3D object modeling. Most existing 3D compression algorithms compress the whole object to reduce the local storage requirement and the delays in transmitting objects over the Internet. However, in some interactive applications, the client may be interested in particular section(s) of the object. The server needs to segment the object into pans and send them individually or sequentially. This paper presents a segmentation based 3D mesh compression scheme that can meet this requirement. We propose an efficient eXtend Multi-Ring neighborhood (XMR) based 3D mesh segmentation algorithm that decomposes the object into meaningful regions. Then we compress them separately and put them into one stream. The common boundary triangles that are used for adhering the regions together are processed and appended to the end of the stream. We call this a region-conquer-and-stitch scheme.
Carbon black dispersions and carbon–silver combinations as thermal pastes that surpass commercial silver and ceramic pastes in providing high thermal contact conductance

Abstract Carbon black dispersions are superior to the best commercial silver and ceramic particle thermal pastes for providing high thermal contact conductance across mating surfaces that are smooth (0.05 μm). For mating surfaces that are rough (15 μm), the combined use of carbon black and silver is more effective than carbon, silver or ceramic pastes. The use of a silver paste to even out the rough surfaces prior to using the carbon black dispersion is more effective than the use of a carbon–silver mixture. For both smooth and rough surfaces, the carbon–silver mixture is superior to silver pastes. The highest conductance attained for rough surfaces is lower than that attained for smooth surfaces.
Nicotine dependence and genetic variation in the nicotinic receptors

Technological advances have led to the discovery of genetic variants that contribute to many illnesses including nicotine dependence. A multi-stage model of the development of nicotine dependence underlies these genetic studies, and it includes a progression through several stages of smoking behavior from never smoking to nicotine dependence. The final step in this model of dependence is the progression from established smoking behavior to the development of nicotine dependence. Contrasting individuals who smoke only a few cigarettes per day, or "chippers", to heavy smoking, nicotine dependent subjects, focuses a genetic study on the transition from smoking to nicotine dependence. This approach has identified distinct genetic variants that contribute to nicotine dependence on chromosome 15 in the region of the alpha5-alpha3-beta4 family of nicotinic receptor genes. This region of association includes an amino acid change in the alpha5 nicotinic receptor protein, which is most likely a biological variant altering the risk of developing dependence. There is also evidence that other variants alter alpha5 nicotinic receptor gene expression and potentially the risk of smoking. The discovery of these genetic variants and their contribution to the development of nicotine dependence highlight some of the many challenges in genetic studies. The first is that the prevalence of risk alleles can vary across populations so that a genetic risk factor can have a larger or small effect in a population depending on its frequency. The second challenge is that the risk that each genetic variant contributes in the development of a disorder is small and so it is many genes along with environmental risk factors that contribute to the development of a disorder. Interestingly, recent genetic studies of lung cancer and chronic obstructive pulmonary disease demonstrate that this same region has an important genetic influence on these disorders. Finally, there are differences in the risk of developing nicotine dependence based on gender and socioeconomic status. As our understanding of the genetic contributions of nicotine dependence increases, we may improve and personalize our treatments for smoking cessation and enhance our knowledge of other smoking related diseases in those who are at high risk for the many adverse consequences of smoking.
The Ambiguity and the Exigency: Clarifying 'Standard of Care' Arguments in International Research

This paper examines the concept of a 'standard of care' as it has been used in recent arguments over the ethics of international human-subjects research. It argues that this concept is ambiguous along two different axes, with the result that there are at least four possible standard of care arguments that have not always been clearly distinguished. As a result, it has been difficult to assess the implications of opposing standard of care arguments, to recognize important differences in their supporting rationales, and even to locate the crux of the disagreement in some instances. The goal of the present discussion, therefore, is to disambiguate the concept of a 'standard of care' and to highlight the areas of genuine disagreement among different standards. In the end it is argued that one standard of care argument in particular is more complex than either its proponents or its critics may have recognized and that understanding this possibility opens up a potentially promising avenue of inquiry that remains to be carefully explored.
Comparison of visible and near infrared reflectance spectroscopy for the detection of faeces/ingesta contaminants for sanitation verification at slaughter plants

Visible and near infrared (NIR) spectra were acquired to explore the potential for the discrimination of faeces/ingesta (“F/I”) objectives from rubber belt and stainless steel (“RB/SS”) backgrounds by using several wavelengths. Spectral features of “F/I” objectives and “RB/SS” backgrounds showed large differences in both visible and NIR regions, due to the diversity of their chemical compositions. These spectral distinctions formed the basis on which to develop simple three-band ratio algorithms for the classifi cation analysis. Meanwhile, score‐score plots from principal component analysis (PCA) indicated the obvious cluster separation between “F/I” objectives and “RB/SS” backgrounds, but the corresponding loadings did not show any specifi c wavelengths for developing effective algorithms. Furthermore, two-class soft independent modelling of class analogy models were developed to compare the correct classifi cations with those from the ratio algorithms. Results indicated that using ratio algorithms in the visible or NIR region could separate “F/I” objectives from “RB/SS” backgrounds with a success rate of over 97%.
The Microcomputer/Programmable Controller Syndrome

As the digital control field incorporates new technology (e.g., bubble memory, very large scale integration (VLSI), fiber optics, Josephsen junctions, etc.), the development of new control tools is advancing at a rapid pace. The board-level microcomputer (MC) and the programmable controller (PC) are two types of controller spinoffs from today's technology. The similarity in the architecture and functions of these units makes proper selection difficult. Guidelines for the selection of MC or PC in industrial control applications are provided.