cssi/SciSciGPT-SciSciNet huggingface dataset:
Cross-sectional associations between weight-related health behaviors and weight misperception among U.S. adolescents with overweight/obesity.

Weight misperception occurs when there is a discrepancy between one’s actual and perceived weight status. Among adolescents with overweight/obesity, many believe that correcting weight misperception is imperative to inspire weight-related behavior change. However, past research has shown that adolescents with overweight/obesity who misperceive their weight status gain less weight over time compared to accurate perceivers. Therefore, our objective was to examine possible mechanisms underlying this relationship. Specifically, we examined the association between weight misperception and engagement in weight-related health behaviors among adolescents with overweight/obesity. Self-reported data from the 2015 National Youth Risk Behavior Survey was used in analyses restricted to participants with overweight/obesity (n = 4383). Using multivariate logistic models correcting for sex, race/ethnicity, and grade in school, we examined the cross-sectional associations between weight misperception and engagement in weight-related health behaviors, specifically related to dietary intake, physical activity, and sleep. Adolescents with overweight/obesity who misperceived their weight status were more likely to drink 100% fruit juice two or more times per day (OR = 1.53, 95% CI: 1.20, 1.94), eat vegetables two or more times per day (OR = 1.29, 95% CI: 1.07, 1.57), be physically active for 1 hour or more per day for at least 5 days in the week prior (OR = 1.40, 95% CI: 1.15, 1.72), be on a sports team in the last year (OR = 1.55, 95% CI: 1.21, 1.97), sleep an average of at least 8 hours per school night (OR = 1.40, 95% CI: 1.15, 1.72), and less likely to be trying to lose weight (OR = 0.17, 95% CI: 0.15, 0.20). Misperceivers were more likely to consume breakfast every morning in the week prior and to drink a sports drink at least once per day, though these results were not statistically significant. We observed no difference in fruit intake, soda intake, or TV viewing between weight misperceivers and accurate perceivers. Overall, weight misperception among adolescents with overweight/obesity was associated with a number of beneficial weight-related health behaviors. Engagement in these healthy weight-related behaviors may explain some of the protective effect of weight misperception on weight gain over time. Not applicable.
Atopic allergy and other hypersensitivities

As Kapsenberg and his colleagues (pp 788-793) have outlined, allergic diseases are associated with the presence of allergen-specific type2 T helper (Th2) cells. It is now clear that in man, as in the mouse, there are two types of helper cell. Thl and Th2 cells produce interleukin (IL)-2 and interferon-y and display cytotoxicity to antigen-presenting B cells, whereas Th2 cells produce IL-4 and IL-5 and provide helper function to B cells. The production of IL-4 by Th2 cells is critical for the IgE antibody response because IL-4 is the IgE switch factor. Kapsenberg addresses the complex and still unresolved issue of what determines the preponderance of Th2 versus Thl cells. The structure of antigen clearly plays a role. This is illustrated by the fact that all individuals regardless of their atopic background respond to antigens from helminthic parasites by making Th2 cells and by IgE isotype production. Furthermore, minute changes in the structure of certain peptides result in the switch from a preponderance of Thl to Th2 cells during an immune response. As would be expected from clinical observations heredity plays a major role in determining whether a Th2 response occurs to allergens. In this respect, experiments by various investigators have shown that atopic individuals make a Th2 response to allergens. The same allergens, when given to normal individuals, elicit only a Thl response. There is tantalizing evidence to suggest that prostaglandin production, which is selec tive to some antigen-presenting cells and which is elevated in individuals with atopy, plays an important role in determining the preponderance of Th2 cells. Indeed, prostaglandin E, and E2 as well as elevation of cyclic AMP, a downstream event of prostaglandin action, inhibit Thl cytokine production by Thl cells, i.e. inhibit interferon-y and IL-2 production, whereas production of IL-4 and IL-5 by Th2 cells is not affected. Remarkably, the bee venom allergen phospholipase A2 which is a potent inducer of prostaglandin synthesis elicits IgE antibod) responses both in allergic and non-allergic individuals. Whether a similar situation will be found in helminthic infections remains to be established.
Chronic Rhinitis Is a High-Risk Comorbidity for 30-Day Hospital Readmission of Patients with Asthma and Chronic Obstructive Pulmonary Disease.

Background Early hospital readmissions for asthma and chronic obstructive pulmonary disease (COPD), measured as hospital readmission within 30 days from the last discharge, is a major economic burden to our health care system. The association of this measure with comorbid chronic rhinitis (CR) has not been investigated before despite significant clinical association between CR and asthma or COPD. Objective To investigate the association of CR with the risk of asthma or COPD-related early hospital readmission rates. Methods This retrospective cohort study was performed using the asthma- and COPD-related hospital encounter and patient comorbidity data between June 15, 2012, and July 19, 2017, from a large hospital care system in Cincinnati, Ohio. Patients (any sex, race or socioeconomic status, and of all ages) with a primary discharge diagnosis of asthma (n = 4754 patients, 10,111 encounters) and COPD (n = 2176 patients, 4748 encounters) based on International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) codes were included. Relevant comorbidities, including comorbid allergic rhinitis (AR) or nonallergic rhinitis (NAR), in such patients were identified using ICD-10-CM codes. The association between 30-day asthma or COPD-related hospital readmission (1670 such encounters for asthma and 736 for COPD) and comorbid CR in the affected patients were determined using Cox proportional hazards models. Multivariate-adjusted hazard ratios (HRs), adjusted for relevant patient comorbidities, compared 30-day asthma- and COPD-related readmissions of patients with CR with those patients without a CR diagnosis. Results Analysis was performed on 4754 patients with asthma and 2176 patients with COPD. The median follow-up period (+interquartile range) for asthma was 980 (+760) days and for COPD was 553 (+827) days. The HRs for 30-day asthma- or COPD-related readmission rates were significantly higher in patients with AR (HR = 4.4 [3.9, 5.0] and 2.4 [1.7, 3.2], respectively) or NAR (HR = 3.7 [2.9, 4.9] and 2.6 [1.8, 3.7], respectively) compared with patients without rhinitis. For asthma, both AR and NAR had higher HRs compared with all other comorbidities analyzed. For COPD, both AR and NAR had HRs to the magnitude as obesity and hypertension. Conclusions Comorbid CR is significantly associated with 30-day asthma- and COPD-related readmissions. These findings are useful for guiding health care professionals to focus on outpatient management of both the upper and lower respiratory tracts to reduce early readmission of patients with asthma and COPD.
Discriminant Functional Learning of Color Features for the Recognition of Facial Action Units and Their Intensities

Color is a fundamental image feature of facial expressions. For example, when we furrow our eyebrows in anger, blood rushes in, turning some face areas red; or when one goes white in fear as a result of the drainage of blood from the face. Surprisingly, these image properties have not been exploited to recognize the facial action units (AUs) associated with these expressions. Herein, we present the first system to do recognition of AUs and their intensities using these functional color changes. These color features are shown to be robust to changes in identity, gender, race, ethnicity, and skin color. Specifically, we identify the chromaticity changes defining the transition of an AU from inactive to active and use an innovative Gabor transform-based algorithm to gain invariance to the timing of these changes. Because these image changes are given by functions rather than vectors, we use functional classifiers to identify the most discriminant color features of an AU and its intensities. We demonstrate that, using these discriminant color features, one can achieve results superior to those of the state-of-the-art. Finally, we define an algorithm that allows us to use the learned functional color representation in still images. This is done by learning the mapping between images and the identified functional color features in videos. Our algorithm works in realtime, i.e., $>$ > 30 frames/second/CPU thread.
Immunophysical Evaluation of the Initiating Step in the Formation of the Membrane Attack Complex

The complex between complement system proteins C5b and C6 is the cornerstone for the assembly of the membrane attack complex (MAC, also known as C5b6789n). MAC is the terminal product of three converging pathways of the complement system and functions as a pore forming complex on cell surfaces, as a response of the immune system in fighting pathogens. However, when proper regulation of the complement system is compromised, MAC also attacks host tissues and contributes to several complement-mediated autoimmune diseases. We performed a molecular dynamics and electrostatics study to elucidate the mechanism of interaction between C5b and C6 and the formation of the C5b6 complex. The C5b-C6 interface consists of three binding sites stabilized predominantly by van der Waals interactions, and several critical salt bridges and hydrogen bonds. We discuss differences between domains C5d and C3d that lead to mono-functionality of C5d in acting as the scaffold for MAC formation, as opposed to dual functionality of C3d in acting as an opsonin for phagocytosis and as a link between innate and adaptive immunity, based on a comparative sequence, structural, and physicochemical analysis. We also extended our analysis to pathway dynamics to demonstrate the significance of consumption-production rates of C5b, C6 and C5b6 that lead towards MAC formation. Finally, we propose that C5d is a target for drug discovery, aiming to the inhibition of the MAC formation in autoimmune diseases originating from MAC-mediated host cell lysis.
Racial disparities in the incidence of colon cancer in patients with inflammatory bowel disease.

Background: Studies have explored the relationship between inflammatory bowel disease (IBD) [ulcerative colitis (UC) and Crohn’s disease (CD)] and colon cancer (CC). Additionally, racial disparities in the incidence of CC is well known. However, the impact of racial disparity in IBD patients who develop CC remains unclear. The aim of this study is to address the knowledge gap in this particular group of patients. Methods: A retrospective analysis was done using the National Inpatient Sample (NIS) database from 2011. We included patients with IBD over age ≥18 years with a diagnosis of CC. Patients were stratified by race, gender, age, presence of IBD and CC. Statistical analysis was performed to compare the groups. Results: A total of 57,542 patients were included (CD: 36,357, UC: 21,001). Of all patients with and without IBD, advanced age, Black and Asian race conferred an increased risk of developing CC, whereas female gender, Hispanic and Native American race conferred a protective effect. In patients with IBD, advanced age conferred an increased risk for developing CC while female gender conferred a protective effect. In this subset of patients, black race conferred a protective effect. Conclusions: Racial disparity exists in the overall incidence of CC and among patients with IBD who develop CC. Interestingly, black race conferred a protective effect for patients with IBD, contrary to what is seen in the general population. These findings could be attributed to the environmental factors and genetic makeup between racial groups. Further studies are warranted to better understand these disparities.
Integrating 3D/4D bioprinting with nanotechnology for complex tissue regeneration (Conference Presentation)

The main objective of our research is to integrate advanced 3D/4D bioprinting techniques with novel biologically inspired nano or smart inks to fabricate the next generation of complex tissue constructs (such as vascularized tissue, neural tissue and osteochondral tissue). The 3D/4D bioprinting techniques offer great precision and control of the internal architecture and outer shape of a scaffold, allowing for close recapitulation of complicated structures found in biological tissues. Specifically, the term “4D” refers to the time-dependent dynamic process triggered by specific stimulation according to predesigned requirements. Our pioneering work in designing innovative 4D bioprinting smart biomaterials has shown huge promise for various tissue regenerative applications. Recently, a 4D bioprinted reprogrammable architecture using light-induced graded internal stress was created for the first time to achieve a 4D+ or 5D concept. Using this novel dual 4D technique, a proof-of-concept nerve guidance conduit was demonstrated with human bone marrow mesenchymal stem cells which were readily differentiated into neural cell types on the graphene hybrid 4D construct providing outstanding multifunctional characteristics for nerve regeneration. In addition, we designed and synthesized biologically inspired nanomaterials (i.e., self-assembly materials, and conductive carbon nanomaterials) as bioinks. Through 3D/4D bioprinting in our lab, a series of biomimetic vascularized and neural tissue scaffolds were successfully fabricated. Our results show that these bioprinted nano or smart scaffolds have not only improved mechanical properties but also excellent cytocompatibility properties for enhancing various stem cell growth and differentiation, thus promising for complex tissue/organ regeneration.
Psychosocial effects of unrelated bone marrow donation: experiences of the National Marrow Donor Program

In this study, we investigated the psychosocial effects of unrelated marrow donation. Survey questionnaires were administered pre-donation, shortly post-donation, and 1 year post-donation to all donors through the National Marrow Donor Program over a 3-year period. Univariate, bivariate, and multivariate analyses were then performed. Donors were generally quite positive about the donation 1 year post-donation: 87% felt it was “very worthwhile” and 91% would be willing to donate again in the future. Marrow donors were more likely than kidney donors to feel better about themselves as a result of the donation (P < .001). Donors with longer collection times, in general, had less positive psychosocial outcomes from the donation. Donors who experienced lower back pain or difficulty walking as a result of the donation were more likely to experience the donation as more stressful and painful than expected, but no more likely to experience it as less positive emotionally than donors who did not experience these side effects.
Optimal Semiconductors for 3H and 63Ni Betavoltaics

Betavoltaic power sources based on the conversion of radioisotope energy to electrical power are considered an appealing option for remote applications due to extended period of operation and high energy densities. However, to be competitive with other power sources, their efficiency must be increased. This can be done through optimization of the beta source and selection of the semiconductor absorber. This paper evaluates available on the market and developing wideband gap semiconductors as prospective absorbers with 3H and 63Ni sources. Simulation results indicate that among wide band gap materials 4H-SiC and diamond are two optimal semiconductors due to the combination of good coupling efficiencies with isotope sources and good electronic transport properties. Additionally, having good coupling efficiency, an ultra-wide bandgap, and the capability for both n- and p-type doping, c-BN is a promising material for betavoltaic applications.
Tailoring diesel bioblendstock from integrated catalytic upgrading of carboxylic acids: a “fuel property first” approach

Lignocellulosic biomass offers the potential to produce renewable fuels at a scale commensurate with petroleum consumption. Hybrid approaches that combine biological and chemocatalytic processes have garnered increasing attention due to their flexibility for feedstock utilization and diversity of potential products. Of note, lignocellulosic sugars can be converted biologically to short-chain carboxylic acids, while subsequent chemocatalytic upgrading can elongate the carbon backbone and remove oxygen from the structure to produce drop-in hydrocarbon fuels. However, hybrid conversion processes are typically not designed with the fuel properties in mind a priori. In this work, we apply a “fuel property first” design approach to produce a tailored hydrocarbon bioblendstock with lower intrinsic sooting and drop-in diesel fuel potential. Initially, model predictions for six fuel properties critical to diesel applications (physicochemical requirements, energy content, safety considerations, autoignition ability, and sooting tendency) were used to screen an array of hydrocarbons accessible from upgrading individual and mixed C2/C4 acids. This screening step allowed for down-selection to a non-cyclic branched C14 hydrocarbon (5-ethyl-4-propylnonane) that can be synthesized from butyric acid through sequential catalytic reactions of acid ketonization, ketone condensation, and hydrodeoxygenation. Following evaluation of each conversion step with model compounds, butyric acid was then converted through an integrated catalytic process scheme to achieve >80% overall carbon yield to a hydrocarbon mixture product containing >60% of the target C14 hydrocarbon. The potential of this conversion strategy to produce a hydrocarbon diesel bioblendstock from lignocellulosic biomass was then demonstrated using corn stover-derived butyric acid produced from Clostridium butyricum fermentation. Experimental fuel property testing of the purified C14 blendstock validated the majority of the fuel property model predictions, including <50% of the intrinsic sooting tendency when compared to conventional diesel. Meanwhile, the crude conversion product met fuel property target metrics, validating conversion process development. When the C14 bioblendstock was blended into a petroleum diesel at 20 vol%, the blend maintained low cloud point, high energy density, and cetane number. Notably, the blend reduced sooting tendency by more than 10%, highlighting the potential of the tailored bioblendstock to reduce particulate emissions.
Natural Selection of Melanism in Costa Rican Jaguar and Oncilla: A Test of Gloger’s Rule and the Temporal Segregation Hypothesis:

The persistence of coat color polymorphisms—such as the coexistence of melanistic and “wild-type” coat color—is an ongoing evolutionary puzzle. We tested the predictions of Gloger’s rule and the Te...
Impact of Alcohol Consumption on Snoring and Sleep Apnea: A Systematic Review and Meta-analysis.

ObjectiveTo systematically review the international literature for studies evaluating the effect of alcohol consumption on the occurrence and severity of snoring and obstructive sleep apnea and to ...
Analytical, Numerical and Experimental Study of Phase Change Material in TIM2 Application for High-Power Server CPUs

The thermal design power (TDP) of server CPU keeps increasing 10-15% generation to generation (G2G) and it pushes the TDP of server CPU to increase to 300+W. In overall thermal stack-up of the server in data center, thermal interface material (TIM) between the CPU and cooling solution is normally called TIM2 to distinguish itself from TIM1 between the die and CPU integrated heat spreader (IHS). There are a few types of TIM2 for this type of application for CPU, including phase change material, grease, thermal pad, and thermal film. Grease is one typical material used as TIM2 due to its relatively lower cost, but risk of pump out in usage is a concern. There have been progresses in PCM, including new phase change material w/ thermal conductivity from 2 to 7 W/k/m. Phase change material (PCM) based TIM2 material is usually characterized by a TIM2 tester. Test results are reported in terms of thermal impedance vs. bond line thickness (BLT) and/or averaged contact pressure. However, thermal performance of phase change material (PCM) collected from TIM2 tester often cannot represent its behavior in actual usage. The primary reason is because the two contacting surfaces typically have warpages that deviate significantly from the relatively flat surfaces used in TIM2 tester. On the CPU side, material set and assembly process used for electronic package of server CPUs often causes the lid of the package to have a warpage value in the range of 200-400 um. On the cooling solution side, its manufacturing processes, due to cost constraints, lead to non-flat surfaces. As a result, the two contacting surfaces where TIM2 lies are not flat and differ from test conditions used in TIM2 tester.In this paper, a model based on Hertzian contact, is presented to estimate TIM2’s effective thermal resistance in real usage. This model allows characterization data to be applied in situations where contact conditions differ from that used in the laboratory. Incidentally, it is found that impedance vs bond-line-thickness (BLT) characterization data is more appropriate than impedance vs pressure characterization data. The experimental data supporting the model are presented as well. Finally, it is pointed out that a more accurate estimate of TIM2 thermal resistance under usage condition can be obtained by using "in-situ" warpage/flatness of the contacting surfaces. How this in-situ warpage/flatness can be estimated via simulation and/or experimental methods is also shared.
Validity Based Approach for Feature Selection in Intrusion Detection Systems

Computer networks are vulnerable to growing number of security threats. The increase of attacks has caused obvious damages throughout the network at individual, enterprise, and government level. Intrusion detection systems are one of the tools that detect and remedy the presence of malicious activities. Intrusion detection systems face many challenges in terms of accurate analysis and evaluation. This paper proposes a new Intrusion detection system by deploying an entropy-based measure called V-measure to select significant features and reduce dimensionality while maintaining high accuracy in classification. The proposed intrusion detection system was tested on the CICIDS2017 dataset by applying machine learning classifiers such as Random Forest, Support Vector Machine, and RepTree algorithms. We then compared the results of the features selected with other features selection tools for correct classification of attacks. The expected results showed that the proposed method reduced irrelevant features and improved detection accuracy of the attacks while reducing the false positive rate.
Value of Combining Patient and Provider Incentives in Humanitarian Healthcare Service Programs

The below-par progress towards the Millennium Development Goals in many developing countries has been attributed to the low availability of good quality healthcare services and to the demand-side barriers to access. In this paper, we analyze an incentive design problem faced by a budget-constrained humanitarian organization managing a healthcare service program (e.g., maternal health or HIV services) with different emphasis on the two measures of quality – structural and process. Incentives offered to the healthcare provider (referred to as supply-side incentives) are aimed at improving the availability of good quality services and demand-side incentives are used to encourage patients to seek care. In many developing country health programs, incentive schemes tend to be purely supply-side focused or purely demand-side focused. However, our results suggest that by offering the right combination of incentives to the patients and the provider, program performance can be increased up to 12 times, on average, depending on the service offered. Even within the current practice of using one-sided incentives, there is significant scope for improvement by ensuring that there is better alignment between the incentive scheme and the service offered. In particular, pure supply-side incentive schemes perform better than pure demand-side incentive schemes in programs where there is a higher emphasis on structural quality. The opposite result holds true for programs that place a higher emphasis on process quality and in fact, pure demand-side incentive schemes are optimal when the program focuses exclusively on process quality.
Moving the needle on global health equity: a look back from 2030.

The timing cannot be better for us to critically reflect about how our scholarly efforts can impact the world we want to see in 2030. It is only by taking the time to pause that we may begin to be ...
The Effect of Social Determinants and Socioeconomic Status on Laparoscopic Roux-En-Y Gastric Bypass for Weight Loss: An Analysis of the National Inpatient Sample

Objective In the United States, Black and Hispanic patients have a higher prevalence of obesity than Whites (49.6 vs. 44.8 vs. 42.2%, respectively). Despite higher rates of obesity among minority populations, bariatric surgery is performed at higher obesity levels in minorities than in Whites. This study examines the effects of various socioeconomic factors such as race, payer type, and income on the likelihood of undergoing laparoscopic Roux-en-Y gastric bypass (LRYGB) at class II versus class III obesity and their associated complications. Materials and Methods National Inpatient Sample (NIS) from 2016 to 2017 was queried to identify patients at least 18 years of age with a concomitant diagnosis of class II or class III obesity who underwent LRYGB. We analyzed obesity level at the time of LRYGB (class II vs. class III), postoperative intestinal obstruction during the admission, and occurrence of any noninfectious complication related to the surgery as our main outcomes. A multivariate logistic regression model was utilized to assess the association between our outcomes and socioeconomic factors associated with the admission. Results A total of 76,405 LRYGB operations were included. Out of this total, 83% (63,640) LRYGB operations were in class III obesity. Black patients had a lower rate (11.6%) of LRYGB procedures at class II obesity than White (17.6%) and Hispanic (18%) patients (p Conclusion Socioeconomic disparities in the surgical management of severe obesity persist in the United States, especially for LRYGB. This study highlights multiple demographic factors that led to LRYGB at later obesity levels. Black patients were also more likely to be associated with postoperative complications during the admission. The determinants of health disparities in obese patients need to be examined further to reduce potential long-term morbidity and mortality in minorities. Further research is also required to identify the adverse effects of health disparities in patients with severe obesity and obesity-related comorbidities.
Point-Based Value Iteration and Approximately Optimal Dynamic Sensor Selection for Linear-Gaussian Processes**This work is supported by DARPA Grant D19AP00078, FOA-AFRL-AFOSR-2019-0003 and NSF Award 1944318.

The problem of synthesizing an optimal sensor selection policy is pertinent to a variety of engineering applications ranging from event detection to autonomous navigation. We consider such a synthesis problem in the context of linear-Gaussian systems over an infinite time horizon with a discounted cost criterion. We formulate this problem in terms of a value iteration over the continuous space of covariance matrices. To obtain a computationally tractable solution, we subsequently formulate an approximate sensor selection problem, which is solvable through a point-based value iteration over a finite “mesh” of covariance matrices with a user-defined bounded trace. We provide theoretical guarantees bounding the suboptimality of the sensor selection policies synthesized through this method and provide numerical examples comparing them to known results.
The influence of turbulence on the sensory basis of rheotaxis

Rheotaxis is a widespread behavior with many potential benefits for fish and other aquatic animals, yet the sensory basis of rheotaxis under different fluvial conditions is still poorly understood. Here, we examine the role that vision and the lateral line play in the rheotactic behavior of a stream-dwelling species (Mexican tetra, Astyanax mexicanus) under both rectilinear and turbulent flow conditions. Turbulence lowered the flow speed at which threshold levels of rheotactic performance were elicited, an effect that was independent of sensory condition. Compared to fish with access to visual information, fish without access exhibited cross-stream casting behaviors and a decrease in the accuracy with which they oriented upstream. Visual deprivation effects were independent of availability of lateral line information and whether flow was rectilinear or turbulent. Fish deprived of lateral line information exhibited no measureable deficits under any of the conditions of this study. This study indicates that rheotactic abilities persist in the absence of both vision and lateral line under both turbulent and non-turbulent conditions, but that turbulence enhances either the motivation or ability of fish to orient to slow currents.
Union Officers and Wildcat Strikes: Freedom from Discriminatory Discipline

doctrine which prevents the discriminatory discipline of union officers fol lowing wildcat strikes. The Board has held that, absent an express provi sion in the contract, no-strike clauses do no imply an affirmative duty owed the employer by union officers to prevent and/or quell unauthorized job actions. Similarly, union officers do not have an "implied higher duty of loyalty" to the contract than do other employees. However, the Board has recognized that because of their status in the shop, union officers, by their actions, can more easily give legitimacy to a wildcat strike. Under these circumstances officers, in effect, become leaders of the strike and can be disciplined, just as any other employee who led a strike. Strong criti cism from a Board minority and the courts has failed to grasp the distinc tions between these different approaches to discipline of union officers. Nevertheless, the Board doctrine comports with traditional agency law and with the realities of industrial relations.
Diffusion of Adsorbed Molecules on Solid Surfaces

We have conducted molecular-dynamics (MD) simulation studies of diffusion in a series of physically adsorbed n-alkanes on a model Pt(111) surface. In addition, we have used transition-state theory (TST) to estimate diffusion-energy barriers for these molecules and to determine the characteristic mechanisms by which they diffuse. The combined studies yield insight into the relationship between molecular structure, size, and mobility. Our studies also reveal some of the unique features associated with molecular mobility, including: unique, one-jump mechanisms for molecular hopping between non-nearest-neighbor binding sites; conformational correlation in molecular hopping; and short-ranged, directional anisotropy in diffusion induced by the molecular degrees of freedom. We discuss some experimental ramifications of these unique features.
Shepherding Loadable Kernel Modules through On-demand Emulation

Despite many advances in system security, rootkits remain a threat to major operating systems. First, this paper discusses why kernel integrity verification is not sufficient to counter all types of kernel rootkits and a confidentiality-violation rootkit is demonstrated to evade all integrity verifiers. Then, the paper presents, DARK, a rootkit prevention system that tracks a suspicious loadable kernel module at a granite level by using on-demand emulation, a technique that dynamically switches a running system between virtualized and emulated execution. Combining the strengths of emulation and virtualization, DARK is able to thoroughly capture the activities of the target module in a guest OS, while maintaining reasonable run-time performance. To address integrity-violation and confidentiality-violation rootkits, we create a group of security policies that can detect all avialiable Linux rootkits. Finally, it is shown that normal guest OS performance is unaffected. The performance is only decreased when rootkits attempt to run, while most rootkits are detected at installation.
Derivatives and Depository Interest Rate Risk: An Empirical Analysis

This paper empirically examines the relationship between the use of on-and-off-balance sheet derivatives and the interest rate risk of US savings associations during 1993-1997. Unlike prior studies, this analysis uses market values, not notional amounts, of all derivatives obtained from the Office of Thrift Supervision?s (OTS) Net Portfolio Value (NPV) Model. The(NPV) model calculates the value of a thrift?s entire portfolio, both on-and-off-balance sheet, to determine each firm?s interest rate risk. We use these data to examine how various factors affect the decision to use or not to use derivatives, whether or not firms use derivatives for hedging. An additional advantage of examining thrifts is that they are end-users of derivatives contracts ? not dealers. The use of derivatives, such as forwards, futures, options, and swaps, by thrifts has not been an industry-wide phenomenon. As of March 1997, only 9.8 percent of savings associations use derivatives. Looking at simple industry averages shows that thrifts using off-balance sheet derivatives, have lower levels of capital, less interest rate risk, and lower net interest margins, than large stock owned-thrifts. However, we also find that thrifts use of derivatives is consistent both with profit maximization and with hedging. After controlling for portfolio and other firm characteristics, we find that thrifts use derivatives to reduce interest rate risk and lessen their vulnerability to capital compliance problems. Further, we find that, after controlling for interest rate risk and credit risk, firms using derivatives have higher net interest margins. We also find that the notable lack of usage by smaller institutions is consistent with rational profit-maximizing behavior as the tendency to avoid derivatives by small institutions is far more pronounced for dealer market products, such as swaps (where low transactions costs can only be obtained by large players), than for exchange-traded products, such as futures. Nevertheless, the lack of derivatives use by most thrifts suggests that a significant segment of the industry is limited in the way it manages interest rate risk.
Going Public After the JOBS Act

The Jumpstart Our Business Startups Act of 2012 (JOBS Act) represents one of the most comprehensive overhauls of the securities laws in recent years. One of the principal goals of the JOBS Act is to improve access to the capital markets for smaller issuers, referred to in the act as emerging growth companies, or EGCs. To accomplish this goal, the JOBS Act seeks to reduce the costs of conducting a public offering and complying with the ensuing reporting obligations by making certain disclosure requirements voluntary for EGCs. This Article examines whether these scaled disclosure rules have increased the number of small issuers conducting an initial public offering (IPO) of their equity securities and the extent to which these issuers have taken advantage of the various exemptions available to them under the JOBS Act. The evidence presented in this Article shows that EGCs have increasingly taken advantage of several of the scaled disclosure provisions of the JOBS Act during their IPOs. EGCs that take advantage of these scaled disclosure provisions are smaller, younger and more likely to belong to the R&D-intensive pharmaceutical industry. Notably, despite the fact that EGCs are embracing these scaled disclosure provisions, there has not been a noticeable increase in the proportion of IPOs conducted by issuers that qualify as EGCs. The Article explores two interrelated explanations for these seemingly contradictory findings. First, the evidence indicates that the benefits of the JOBS Act may not be as significant as may have been expected. While the direct costs of conducting an IPO have not decreased for EGCs following the enactment of the JOBS Act, indirect costs may have actually increased. In addition, by their second fiscal year, over forty percent of issuers that went public as EGCs no longer qualify for such status, a fact that limits the expected ongoing benefits of the JOBS Act at the going public decision stage. Second, certain issuers that qualify for EGC status may be choosing to pursue private offerings, which certain provisions of the JOBS Act facilitate. Changes in the mix of small issuers going public following the enactment of the JOBS Act suggest such a shift in the pattern of going public decisions across firms.
Fibrotic tissue growth into the extendable lobes of an active fixation coronary sinus lead can complicate extraction

Extraction of passive fixation coronary sinus (CS) leads is typically easily achieved with manual traction. The ability to readily extract active fixation leads from the CS is less clear. Our first extraction experience with an active fixation CS lead was in a 58-year-old man with a 13-month-old Medtronic 4195 lead (Medtronic Inc., Minneapolis, MN, USA). The lobes of the lead would not fully undeploy. Significant, prolonged manual traction was required to free the lead from the cardiac vein. Inspection demonstrated fibrotic tissue growth into the lead lobes. Such growth may lead to an increase in extraction complications and failures.
Catalysis by Yeast Alcohol Dehydrogenase

The structure and mechanism of alcohol dehydrogenases have been extensively studied (Branden et al., 1975; Klinman, 1981; Pettersson, 1987). The three-dimensional structures of the horse liver enzyme in several ternary complexes have been solved at high resolution (Eklund et al., 1981, 1982). Amino acid sequences for more than 22 NAD+-dependent alcohol dehydrogenases from 11 animal, plant and fungal species are known. Comparison of these sequences raises many questions about the structure-function relationships in these enzymes. How do the amino acid residues at the active site participate in catalysis? What is the basis of substrate specificity? What was selected for during the evolution of the different enzymes?
Object-oriented real-time distributed programming and support middleware

The object oriented (OO) distributed real time (RT) programming movement started in the 1990s and is growing rapidly at this turn of this century (year 2000). The motivations are reviewed and then a brief overview is given of the particular programming scheme which the author and his collaborators have been establishing. The scheme is called the time triggered message triggered object (TMO) programming scheme and it is used to make specific illustrations of the issues and potentials of OO RT programming. The desirable features of middleware providing execution support for OO RT distributed programs are then discussed. The issue of fault tolerant execution of distributed RT objects and that of RT distributed/parallel simulation are also discussed.
RECOMBINATION BETWEEN GENES LOCATED ON NONHOMOLOGOUS CHROMOSOMES IN SACCHAROMYCES CEREVISIAE

We constructed strains of Saccharomyces cerevisiae that contained two different mutant alleles of either the leu2 gene or the ura3 gene. These repeated genes were located on nonhomologous chromosomes; the two ura3- alleles were located on chromosomes V and XII and the two leu2- alleles were located on chromosomes III and XII. Genetic interactions between the two mutant copies of a gene were detected by the generation of either Leu+ or Ura+ revertants. Both spontaneous and ultraviolet irradiation-induced revertants were examined. By genetic and physical analysis, we have shown that Leu+ or Ura+ revertants can arise by a variety of different genetic interactions. The most common type of genetic interaction is the nonreciprocal transfer of information from one repeat to the other. We also detected reciprocal recombination between repeated genes, resulting in reciprocally translocated chromosomes.
Detection of Inadvertent Airway Intubation During Gastric Tube Insertion: Capnography Versus a Colorimetric Carbon Dioxide Detector

• BACKGROUND In the medical intensive care unit at the University of Virginia Health System, capnography is used to detect end-tidal carbon dioxide to protect patients from inadvertent airway cannulation during placement of gastric tubes. • OBJECTIVES To compare the method in which capnography is used with a method in which a colorimetric carbon dioxide detector is used and to determine what variables affect accurate placement of gastric tubes. • METHODS A prospective convenience sample of 195 gastric tube insertions was studied in 130 adult patients in a medical intensive care unit. Standard insertions of gastric tubes (done with capnography) were simultaneously monitored by using a disposable colorimetric device, with a color change indicating the presence of carbon dioxide. • RESULTS Insertion variables included tube type (60% Salem sump tubes, 40% soft-bore feeding tubes), route of insertion (71% oral, 29% nasal), mechanical ventilation (81%), and decreased mental status (72%). Carbon dioxide was successfully detected with the colorimetric indicator (within seconds) in all insertions in which carbon dioxide was detected by capnography. When carbon dioxide was detected (27% of insertions), the tubes were withdrawn and reinserted. Carbon dioxide detection during tube placement was significantly associated with nasal insertions (P = .03) and spontaneously breathing/nonintubated status (P = .01) but not with mental status or tube type. • CONCLUSIONS A colorimetric device is as accurate as capnography for detecting carbon dioxide during placement of gastric tubes. (American Journal of Critical Care. 2006;15:188-195)
A TLV-structured data naming scheme for content-oriented networking

Content-oriented networking (CON) addresses the inefficiency of IP networks in supporting content distribution, by decoupling location from identity at the network level, and retrieving a content object through its name or identifier, instead of its storage location or host IP address. A naming scheme is critical in CON designs because a name is used to identify the object and acts as the key for location resolution and routing. This paper proposes a new TLV-structured naming scheme with Bloom filter summarization. The proposed scheme satisfies the requirements of name uniqueness and persistence, and enables more secure content-oriented trust model and effective routing state aggregation for scalability. It also addresses the “suffixhole” problem encountered in conventional prefix-based routing aggregation. We analyzed the performance of the proposed TLV-structured naming and Bloom filter aggregation scheme and our early evaluation results shows that the proposed scheme greatly outperforms the prefix-based aggregation in terms of routing resolution error probability.
Can we learn from eugenics

Eugenics casts a long shadow over contemporary genetics. Any measure, whether in clinical genetics or biotechnology, which is suspected of eugenic intent is likely to be opposed on that ground. Yet there is little consensus on what this word signifies, and often only a remote connection to the very complex set of social movements which took that name. After a brief historical summary of eugenics, this essay attempts to locate any wrongs inherent in eugenic doctrines. Four candidates are examined and rejected. The moral challenge posed by eugenics for genetics in our own time, I argue, is to achieve social justice.
Simulated hygrothermal performance of a Passivhaus in a mixed humid climate under dynamic load

Abstract This paper details the dynamic simulation of a small, super insulated Passivhaus residential structure, namely The Ohio State University's entry into the 2011 Solar Decathlon competition. This study explores the use of a conventional vapor compression conditioning system as well as the effects of occupant behavior on the parameters affecting comfort within the structure. It adds to the current literature on the subject by presenting a simulation of a Passivhaus and its HVAC system in a mixed climate where cooling and dehumidification are traditionally required. Furthermore it adopts a simulation tool which acts on time scales significantly less than 1 h. It is concluded that the house, while energy efficient, has difficultly controlling moisture levels. In the summer season it is too humid, and in the winter it is too dry. The study concludes that conventional HVAC equipment cannot fully address the moisture and indoor air quality issues that are a result of new building techniques with stringent air infiltration and insulation standards.
A model for parallel machine replacement with capacity expansion

Abstract This paper considers an environment where several identical machines are used to meet product/service demands. It is assumed that the product/service demand is growing over time and therefore new machines will be purchased for capacity expansion. Also, older machines are assumed to be more expensive to operate than newer machines; and at some time, it may be economical to replace older machines by newer ones. There may be economies of scale in purchase of new machines. This paper develops an integrated model to find an optimal purchase schedule of new machines to meet both the capacity expansion and the machines replacement requirements. An optimal algorithm and an effective heuristic are developed. Our computational results show that the heuristic is close to optimal.
Spin-selective localization due to intrinsic spin-orbit coupling

We study spin-dependent diffusive transport in the presence of a tunable spin-orbit (SO) interaction in a two-dimensional electron system. The spin precession of an electron in the SO coupling field is expressed in terms of a covariant curvature, affecting the quantum interference between different electronic trajectories. Controlling this curvature field by modulating the SO coupling strength and its gradients by, e.g., electric or elastic means, opens intriguing possibilities for exploring spin-selective localization physics. In particular, applying a weak magnetic field allows the control of the electron localization independently for two spin directions, with the spin-quantization axis that could be ``engineered'' by appropriate SO interaction gradients.