cssi/SciSciGPT-SciSciNet huggingface dataset:
Compressing backoff in CSMA networks

Randomized backoff is a well-established approach for avoiding collisions in CSMA networks. Today's backoff operation, such as in WiFi, attempts to create a total ordering among all the nodes contending for the channel. Total ordering requires assigning a unique backoff to each node, which is achieved by having nodes choose their back-offs from a large range, ultimately leading to channel wastage. This paper observes that total ordering can be achieved more efficiently. We propose “hierarchical backoff” in which nodes pick random numbers from a smaller range, resulting in groups of nodes picking the same number (i.e., partial order). Now, the group of nodes that picks the smallest number is advanced to a second round, where they again perform the same operation. This results in more efficient backoff because the time for partially ordering all nodes plus totally ordering each small groups is actually less than the time needed to totally order all nodes. Realizing the above intuition requires addressing new protocol challenges in group signaling, the feasibility of which is demonstrated on a USRP/GNUradio prototype. Large scale simulations also show consistent throughput gains by incorporating the proposed backoff approach into two CSMA protocols - WiFi and oCSMA. We also show that the proposed approach can be complementary to and even outperform existing backoff optimization schemes.
Scattering from surface impedance sphere coated with dielectric materials

An exact solution of surface impedance sphere coated with dielectric materials is presented in Mie series form. The solution accuracy is verified by comparing with other exact formulations as well as the numerical solution based on the method of moments. Different numerical examples are presented in order to illustrate the effect of the material types on the scattered fields.
Facility-level variation in diabetes and blood pressure control in patients with diabetes: Findings from the Veterans Affairs national database.

Background Intensive glycemic and blood pressure (BP) control in diabetic patients is associated with improved cardiovascular outcomes. Hypothesis We hypothesized that there is suboptimal glycemic and BP control with significant facility-level variation in patients with diabetes. Methods We identified patients with diabetes receiving care in 130 facilities in the Veterans Affairs Health Care System. We assessed facility-level rates of glycemic (hemoglobin [Hb]A1c <7%), BP (BP <140/90 mmHg), and combined glycemic and BP control (HbA1c <7% and BP <140/90 mmHg), and their facility-level variation in using median rate ratios (MRR). Results Among 1 103 302 patients with diabetes, 50.2% participants had an HbA1c <7%, 77.5% had a BP <140/90 mmHg, and 39.8% had both, HbA1c <7% and BP <140/90 mmHg. Median facility-level rates were 50.3% (interquartile range [IQR], 47.9%–52.4%) for glycemic control, 78.4% (IQR, 75.2%–80.0%) for BP control, and 39.9% (IQR, 38.14%–42.34%) for combined glycemic and BP control. Unadjusted MRR for glycemic control was 1.61 (95% confidence interval [CI]: 1.51-1.70) which decreased to 1.16 (95% CI: 1.14-1.19) after adjusting for patient and facility-level variables, indicating a 16% variation in glycemic control between 2 identical patients receiving care at 2 random facilities. Unadjusted MRR for BP control was 1.49 (95% CI: 1.41-1.56), which decreased to 1.25 (95% CI: 1.21-1.28), whereas unadjusted MRR for combined glycemic and BP control was 1.59 (95% CI: 1.50-1.68), which decreased to 1.15 (95% CI: 1.13-1.17) after adjustment. Conclusions Facility-level rates for BP control and glycemic control remain low with significant facility-level variation. Much of this is explained by patient and facility-level variables although 16%, 25%, and 15% variation in glycemic, BP, and combined glycemic and BP control remains unexplained.
The Persistent Problem of Local/Regional Failure After Surgical Intervention for Early-Stage Lung Cancer.

Background The goal of the present study was to estimate the rate of local/regional failure (LRF) after definitive surgical intervention for early-stage non-small cell lung cancer (NSCLC), without postoperative radiotherapy, in the era of contemporary imaging and minimally invasive surgical techniques. Methods Medical records of patients with early-stage NSCLC (pathologic T1-4, N0-1) who underwent lobectomy, sleeve lobectomy, bilobectomy, or pneumonectomy, with or without adjuvant chemotherapy, between 2007 and 2015, were retrospectively reviewed. LRF was defined as recurrence at the ipsilateral lung, bronchial stump, mediastinum, chest wall, or supraclavicular region. The Kaplan-Meier method was used to estimate time to LRF, with patients censored at death, and log-rank tests were used for comparisons. A two-sided p value of less than 0.05 was considered significant. Results Included were 217 patients (median age, 65 years). Preoperative staging with positron emission tomography/computed tomography was performed in 89% of patients, mediastinoscopy was performed in 42%, and video-assisted thoracoscopic surgery was performed in 51%. At a median follow-up of 36 months (range, 1 to 120 months), the 5-year estimated LRF was 26% (95% confidence interval, 20% to 35%). LRF rates were not significantly different in those with and without staging positron emission tomography/computed tomography (hazard ratio, 1.52; p = 0.43) and those with video-assisted thoracoscopic surgery versus open thoracotomy (hazard ratio, 1.00; p = 0.99). Conclusions Despite contemporary staging procedures and surgical techniques for early-stage NSCLC, LRF occurs in approximately 1 of 4 patients. The observed rates of LRF are similar to those reported more than a decade ago, suggesting that local/regional control remains a persistent problem. The use of additional local treatments, such as radiotherapy, should be reevaluated to further improve outcomes.
Religion, Nonreligion, and Deviance: Comparing Faith’s and Family’s Relative Strength in Promoting Social Conformity

The view that religion, as a source of moral guidance and social support, can function to prevent or protect individuals, especially children and adolescents, from a range of deviant and delinquent behaviors is largely (but not completely) born out in the literature. In nations with strong religious identities such as the USA, there is a normative expectation that adolescents who identify with religion are less likely to engage in deviant behavior than those who claim no religion. The present study explores this issue using data from over 10,000 American middle school and high school youth to examine the relationship between religion, nonreligion, and various forms of deviance. Results indicate that youth who identify with a religious (rather than nonreligious) label are not less likely to be involved in deviant acts after controlling for protective factors. The effects from some of these protective factors are significant and stronger than the effects from religion.
Corticobasal degeneration with TDP-43 pathology presenting with progressive supranuclear palsy syndrome: a distinct clinicopathologic subtype

Corticobasal degeneration (CBD) is a clinically heterogeneous tauopathy, which has overlapping clinicopathologic and genetic characteristics with progressive supranuclear palsy (PSP). This study aimed to elucidate whether transactive response DNA-binding protein of 43 kDa (TDP-43) pathology contributes to clinicopathologic heterogeneity of CBD. Paraffin-embedded sections of the midbrain, pons, subthalamic nucleus, and basal forebrain from 187 autopsy-confirmed CBD cases were screened with immunohistochemistry for phospho-TDP-43. In cases with TDP-43 pathology, additional brain regions (i.e., precentral, cingulate, and superior frontal gyri, hippocampus, medulla, and cerebellum) were immunostained. Hierarchical clustering analysis was performed based on the topographical distribution and severity of TDP-43 pathology, and clinicopathologic and genetic features were compared between the clusters. TDP-43 pathology was observed in 45% of CBD cases, most frequently in midbrain tegmentum (80% of TDP-43-positive cases), followed by subthalamic nucleus (69%). TDP-43-positive CBD was divided into TDP-limited (52%) and TDP-severe (48%) by hierarchical clustering analysis. TDP-severe patients were more likely to have been diagnosed clinically as PSP compared to TDP-limited and TDP-negative patients (80 vs 32 vs 30%, P < 0.001). The presence of downward gaze palsy was the strongest factor for the antemortem diagnosis of PSP, and severe TDP-43 pathology in the midbrain tectum was strongly associated with downward gaze palsy. In addition, tau burden in the olivopontocerebellar system was significantly greater in TDP-positive than TDP-negative CBD. Genetic analyses revealed that MAPT H1/H1 genotype frequency was significantly lower in TDP-severe than in TDP-negative and TDP-limited CBD (65 vs 89 vs 91%, P < 0.001). The homozygous minor allele frequencies in GRN rs5848 and TMEM106B rs3173615 were not significantly different between the three groups. In conclusion, the present study indicates that CBD with severe TDP-43 pathology is a distinct clinicopathologic subtype of CBD, characterized by PSP-like clinical presentations, severe tau pathology in the olivopontocerebellar system, and low frequency of MAPT H1 haplotype.
GIS and Spatio-temporal Trends in Inequality: Tracking Profitability According to Firm Size in Japanese Manufacturing, 1985–2006

This chapter examines the spatial patterns of profitability in Japanese manufacturing according to the size of the firm from 1985 to 2006. The study period captures the ‘‘bubble economy’’ of the late 1980s, the economic downturn and restructuring of the 1990s, and the economic expansion of the early 2000s. The Theil index of inequality and LISA cluster maps are used to identify trends in average profitability for six firm size categories. The results show that average profitability tends to decline along with firm size, and that instability in average profitability for larger size firms tended to be a major contribution to changes in total inequality. For much of the study period contributions from larger firms to inequality between the firm size categories was decreasing while their contributions to regional inequality were increasing. The analysis also suggests that there is substantial variation in average profitability trends for prefectures in the core manufacturing region.
Abstract TP232: Telestroke and Direct-to-Hub tPA Treatment Rates are Similar at Academic Comprehensive Stroke Program

Introduction: Telestroke is a practical tool to increasing stroke care delivery. Our aim was to investigate whether patients treated with intravenous tissue plasminogen activator (IV tPA) at the sp...
Multicast Routing Using Delay Intervals for Collaborative and Competitive Applications

Collaborative and competitive applications require that participants receive messages almost simultaneously and before a specified time. These requirements have been addressed by the delay variation-bounded multicasting tree (DVBMT) problem. In this paper, we propose the interval multicast subgraph (IMS) problem to address these requirements. IMS addresses these constraints with an interval of acceptable delay values for paths as user input from a source to a destination, eliminating the need to optimize delays for a variation value. By solving IMS rather than DVBMT and other variants of DVBMT, we are able to find solutions for larger graphs more efficiently. Our proposed interval multicast algorithm (IMA) accounts for an interval of acceptable delay as user input and guarantees the weight of each path from the source to a distinct destination is within the given interval if that path exists. We provide proofs of correctness and complexity of IMA, as well as simulation experiments, to illustrate the effects of various parameters on our algorithm. Simulations show that IMS is significantly less costly than finding the minimum variation for the average and best case. By remodeling the DVBMT problem to IMS, we have created a new problem that addresses the quality of service requirements of multicasting and is able to be solved efficiently for the average case for relatively large graphs.
Interoceptive deficits, non-suicidal self-injury, and suicide risk: a multi-sample study of indirect effects.

BackgroundInteroceptive deficits (ID) have been associated with non-suicidal self-injury (NSSI) and suicidal behavior in multiple studies. Many of these studies are limited in scope, and have not fully examined possible mechanisms explaining how ID affect suicidal behavior.MethodsThis study assesses how self-reported ID relate to suicide ideation and attempts in six distinct and geographically diverse samples of adults (n = 2706) and one sample of adolescents (n = 436). Participants responded to a variety of self-report questionnaires and interviews.ResultsContrary to our hypothesis, self-reported ID were only associated with suicidal ideation in two samples, one of which was the adolescent sample. Largely consistent with our predictions, self-reported ID exhibited an indirect effect on suicide attempts through versatility of NSSI in four of the five adult samples tested. Finally, the indirect effects of self-reported ID on suicide attempts through NSSI versatility did not act indirectly through behaviorally assessed pain tolerance.ConclusionsWe found that, in adults, self-reported ID are not associated with suicidal ideation, but are connected with a history of suicide attempts, through an indirect effect via NSSI. Our findings also indicate that the mechanism of action leading from self-reported ID to suicidal behavior may differ between adolescents and adults, and relate to suicidal behavior independent of pain tolerance. Clinical implications and future directions are discussed.
Tricritical Points and Bifurcations in a Quartic Map

We have studied the 1-dimensional iteration map associated with the even quartic polynomial x n+l = 1 + a x 2 n + b x 4 n .This map allows a smooth transition from a single hump to a double hump. Bifurcations and higher-order transitions occur as we vary the parameters a, b. In addition to the usual universal bifurcation behavior discovered by Feigenbaum, we find a new universality class of bifurcations which is associated with a tricritical point. Tricritical points serve as natural boundaries toFeigenbaum critical lines. For the quartic map, the tricritical points which are the end-points of the original Feigenbaum line are (a,b) = (0, -1.59490) and (-2.81403, 1.40701). Associated with each tricritical point, there are two unstable directions as well as two independent exponents. The exponents are δ 1 T = 7.2851 andδ 2 T = 2.8571. At the tricritical point, we can introduce a universal function f* T (x) which obeys α T f* T (f* T (x/α T )) = f* T (x) with the scale factor α T = -1.69031. The quartic map has a, special duality transformation (a,b) ⇔ (a',ba'), such that the two mappings are intrinsically related. The tricritical points which are dual to the above pair of tricritical points are located at (-3.18980, 2.54371) and at (.95561, -1.14981) and are joined by a line which is the dual of the original Feigenbaum line. There are an infinite number of different tricritical points which form at least a Cantor set.
Supervised Deep Sparse Coding Networks for Image Classification

In this paper, we propose a novel deep sparse coding network (SCN) capable of efficiently adapting its own regularization parameters for a given application. The network is trained end-to-end with a supervised task-driven learning algorithm via error backpropagation. During training, the network learns both the dictionaries and the regularization parameters of each sparse coding layer so that the reconstructive dictionaries are smoothly transformed into increasingly discriminative representations. In addition, the adaptive regularization also offers the network more flexibility to adjust sparsity levels. Furthermore, we have devised a sparse coding layer utilizing a “skinny” dictionary. Integral to computational efficiency, these skinny dictionaries compress the high-dimensional sparse codes into lower dimensional structures. The adaptivity and discriminability of our 15-layer SCN are demonstrated on six benchmark datasets, namely Cifar-10, Cifar-100, STL-10, SVHN, MNIST, and ImageNet, most of which are considered difficult for sparse coding models. Experimental results show that our architecture overwhelmingly outperforms traditional one-layer sparse coding architectures while using much fewer parameters. Moreover, our multilayer architecture exploits the benefits of depth with sparse coding’s characteristic ability to operate on smaller datasets. In such data-constrained scenarios, our technique demonstrates a highly competitive performance compared with the deep neural networks.
"Who's Got the Power?": A Critical Examination of the Anti-Bias Curriculum.

Ample research data indicate that young children recognize racial characteristics and subsequently exhibit both positive and negative racial attitudes toward their own and other racial groups. In the early childhood field, educators commonly adopt an anti-bias/multicultural curriculum to address such issues with young children and—with rare exceptions—such methods are subject to ongoing endorsement in the scholarly literature. This article, however, offers a more comprehensive critique of the anti-bias curriculum, including an analysis of the conceptual frameworks underpinning several of the associated teaching strategies. In addition, the present article illustrates how the anti-bias curriculum, though presented as congruent with the empirical evidence with respect to the education of young children and race, departs considerably from these data. Furthermore, the curricula under scrutiny fail to engage young children in critical discussions and classroom practices centering on: (i) power relations; (ii) racism; (iii) whiteness; and (iv) white privilege. This critique concludes with a preliminary conceptualization of anti-racism in early childhood education.
Drying kinetics and quality characteristics of green apple peel (Mallus communis L. var. “Granny Smith”) used in herbal tea production

Green apple peels, (25.06 ± 0.06 g) with the moisture content of 3.05 ± 0.02 [kg (moisture) kg–¹ (dry matter)], were dried using two dehydration methods, microwave, and natural drying until moisture content of apple peels was reduced to 0.092 ± 0.001 [kg (moisture) kg–¹ (dry matter)]. Microwave drying periods at 1,000, 800, 600, and 400 W lasted for 17, 21, 27, and 33 min, respectively; whereas, natural drying lasted for 66 hr. The scope of this study, a comparison of measurements of moisture with that of the predicted results was made, obtained from 21 thin layer drying models. For both 600 and 800 W microwave drying, Modified Henderson and Pabis's model; whereas, at 1,000 W, Alibas's model, and at 400 W, Modified Jena and Das's model were considered to be the most appropriate models. The most suitable drying process according to color parameters, chlorophyll content, and nutrients was obtained at 400 W microwave drying. PRACTICAL APPLICATIONS: The herbal tea industry is growing globally and it is constanrly looking for new flavors that can attact consumers' attention. Herbal teas, in addition to being delicious, are required to meet the daily nutritional needs of the consumers. One of the drawbacks of drying is the loss of aroma and nutrients, moreover, drying operations carried out in open fields, such as sun drying, leads to contamination and can cause more harm than benefit. Thus, for food safety, it is very essential for herbal tea production facilities to use appropiriate methods to produce high‐quality products. The present study on drying of apple peels for herbal tea contains important data on the selection of the most suitable drying method for the preservation of nutrients.
Hybrid Cellulose Nanocrystal-Bonded Carbon Nanotubes/Carbon Fiber Polymer Composites for Structural Applications

Integrating carbon nanotubes (CNTs) in carbon fiber reinforced polymer (CFRP) composites enhances structural and functional properties; however, it often involves chemical functionalization or proc...
Solar Cogeneration of Electricity with High-Temperature Process Heat

Summary Side-by-side installations of flat plate photovoltaics and parabolic trough collectors consume significant space and have high system losses; by using an all-in-one, spectrum-splitting hybrid receiver, electricity and high-temperature heat can be generated with a single efficient system. Here, the performance of a transmissive concentrator photovoltaic/thermal (tCPV/T) system is demonstrated on-sun, with a total energy efficiency of 85.1% ± 3.3%, 138 W electric power at 304 suns (with average cell temperatures
Some Concluding Thoughts

The final chapter of this Advances in Rasch Analysis in the Human Sciences includes a summary of the concepts we have presented. We also provide an overview of how Advances in Rasch Analysis in the Human Sciences links to Rasch Analysis in the Human Sciences. Finally, we provide a broad set of steps a researcher might use based on the topics of presented in Advances in Rasch Analysis in the Human Sciences and in Rasch Analysis in the Human Sciences as readers seek to develop and use measurement instruments (tests, surveys) using Rasch techniques. Also, we suggest the steps that researchers should use as they seek to communicate their research findings in an understandable manner.
0.36-mW, 52-Mbps True Random Number Generator Based on a Stochastic Delta–Sigma Modulator

This letter presents a true random number generator (TRNG) based on a stochastic delta–sigma modulator (DSM) with ring oscillator (RO) integrators. The TRNG leverages noise and jitter in the ROs as entropy source. A multibit nonreturn-to-zero (NRZ) digital-to-analog converter (DAC) in the feedback path ensures DSM noise dominates input swing seen by the front-end integrators. Hence, the DSM can concurrently operate as an ADC and TRNG. A 65-nm prototype achieves Shannon entropy > 0.999998 with lower-bound min-entropy > 0.995 at 52 Mb/s throughput while passing all NIST tests across multiple chips and voltage/temperature corners without needing calibration. The combined power consumption of ADC and TRNG is 0.36 mW which is the lowest among state-of-the-art RO TRNGs. Low power consumption, high entropy, and concurrent operation of the TRNG as an ADC are principal contributions of this letter.
Physicians and Social Determinants of Health.

To the Editor In their Viewpoint, Drs Maani and Galea considered how physicians can most effectively support societal efforts to alleviate adverse social determinants of health to improve the health of individuals in the United States.1 The authors suggested that physician-level interventions distract from what ultimately must be systemic efforts—a proposition we believe overlooks the profound mitigating effect physicians can have on social determinants of health.
Estimation of a distribution function with increasing failure rate average

Abstract A life distribution function F is said to have an increasing failure rate average if H ( x ) ∕ x is nondecreasing where H ( x ) is the corresponding cumulative hazard function. In this paper we provide a uniformly strongly consistent estimator of F and derive the convergence in distribution of the estimator at a point where H ( x ) ∕ x is increasing using the arg max theorem. We also show using simulations that, unlike other estimators of the past, this new estimator outperforms the empirical distribution in terms of mean square error at all quantiles. An example is also discussed to illustrate the theoretical results
Recent Developments in the Evaluation and Application of Residual and Fully Softened Shear Strengths for the Stability Analyses of Landslides

Shear strength is an essential component of slope stability analyses and necessary for the design of landslide repair and prevention works. This paper provides an in-depth review of the shear strength of soil pertinent to landslide analysis—fully softened shear strength and the residual shear strength of soils. Methods currently used in practice to measures the fully softened and residual shear strengths are summarized along with their advantages and disadvantages. Specifically, this paper will present details regarding the methods used to measure these shearing resistances, such as direct shear, ring shear, triaxial compression and direct simple shear tests to measure the fully softened shear strength and the use of direct shear, ring shear and triaxial compression tests to obtain the residual shear strengths. Pertinent information and discussions are provided regarding the interpretation of the shear envelopes developed from these testing methods focusing on the use of linear and non-linear (or curved) failure envelopes along with the interpretation of the strengths in terms of the secant friction angles. The various forms of curved linear envelopes presented in the literature are discussed. The paper also includes details of several commonly used correlations to estimate both the fully softened and residual shear strengths. Recommendations by the authors on the use, measurement and interpretation of both the fully softened and residual shear strengths are also included.
Building Machines that Learn and Think Like People

Recent successes in artificial intelligence and machine learning have been largely driven by methods for sophisticated pattern recognition, including deep neural networks and other data-intensive methods. But human intelligence is more than just pattern recognition. And no machine system yet built has anything like the flexible, general-purpose commonsense grasp of the world that we can see in even a one-year-old human infant. I will consider how we might capture the basic learning and thinking abilities humans possess from early childhood, as one route to building more human-like forms of machine learning and thinking. At the heart of human common sense is our ability to model the physical and social environment around us: to explain and understand what we see, to imagine things we could see but haven't yet, to solve problems and plan actions to make these things real, and to build new models as we learn more about the world. I will focus on our recent work reverse-engineering these capacities using methods from probabilistic programming, program induction and program synthesis, which together with deep learning methods and video game simulation engines, provide a toolkit for the joint enterprise of modeling human intelligence and making AI systems smarter in more human-like ways.
Retinoids promote penis development in sequentially hermaphroditic snails.

Abstract Sexual systems are surprisingly diverse, considering the ubiquity of sexual reproduction. Sequential hermaphroditism, the ability of an individual to change sex, has emerged multiple times independently across the animal kingdom. In molluscs, repeated shifts between ancestrally separate sexes and hermaphroditism are generally found at the level of family and above, suggesting recruitment of deeply conserved mechanisms. Despite this, molecular mechanisms of sexual development are poorly known. In molluscs with separate sexes, endocrine disrupting toxins bind the retinoid X receptor (RXR), activating ectopic male development in females, suggesting the retinoid pathway as a candidate controlling sexual transitions in sequential hermaphrodites. We therefore tested the role of retinoic acid signaling in sequentially hermaphroditic Crepidula snails, which develop first into males, then change sex, maturing into females. We show that retinoid agonists induce precocious penis growth in juveniles and superimposition of male development in females. Combining RXR antagonists with retinoid agonists significantly reduces penis length in induced juveniles, while similar treatments using retinoic acid receptor (RAR) antagonists increase penis length. Transcripts of both receptors are expressed in the induced penis. Our findings therefore show that retinoid signaling can initiate molluscan male genital development, and regulate penis length. Further, we show that retinoids induce ectopic male development in multiple Crepidula species. Species-specific influence of conspecific induction of sexual transitions correlates with responsiveness to retinoids. We propose that retinoid signaling plays a conserved role in molluscan male development, and that shifts in the timing of retinoid signaling may have been important for the origins of sequential hermaphroditism within molluscs.
Analytical Pitfalls with Tricyclic and Newer Antidepressants in Biological Samples

With antidepressants and their active metabolites there are analytical complications: low concentrations; surface adsorptivity during extraction; chromatographic co-elution with other drugs and contaminants; and uncertainty about survival during storage and chromatography. Stability experience with the tricyclics does not hold for newer antidepressants. Thus, bupropion (but not its three major metabolites) showed temperature- and pH-dependent log-linear degradation in plasma. The importance of validating extraction techniques for each sample type is exemplified by trazodone, which was extractable from plasma by methyl-t-butyl ether but required isoamyl alcohol/hexane for brain tissue extraction to obviate emulsions and include an active metabolite. For cyclic antidepressants in general, sources of inaccuracy include the preparation of non-methanolic stock solutions, mode of rendering alkaline, standard-curve determination with homogenates of the tissue concerned, and HPLC validation with a converse-polarity system, e.g. NP instead of RP. Other points of practice are also discussed, e.g. sample collection, in the context of inter-laboratory differences in assay performance.
Structural studies on polypeptide hormones: II. Parathyroid hormone

Abstract The molecular properties of bovine and porcine parathyroid hormone have been studied by circular dichroism and fluorescence. The effects of pH on the tryptophanyl fluorescence of both species and on the peptide optical activity of the bovine hormone have been evaluated. The data obtained show that there are constraints on the rotational freedom of the polypeptide backbone in both hormones. Therefore, parathyroid hormone cannot be characterized either as possessing the fully organized structure of a protein or the random coil structure of charged polylysine or polyglutamate.
Using student characteristics as the focal point for improving instruction

This article describes an instructional improvement program currently underway at the University of Minnesota. The program’s overall goal is to help faculty become aware of and adapt their instructional strategies to the developmental and learning characteristics of students. The first section provides an overview of the assumptions that underlie the program. The next section describes the roles of the faculty consultant and faculty member and discusses the process used in the faculty consultation model. Finally, a sample of discussion from one of the faculty seminars is used to highlight the process.
IRAS observations of an optical sample of interacting galaxies

IRAS observations of an optically selected sample of closely interacting disk galaxies and comparisons with a control sample of isolated disk galaxies indicates that the interaction leads to enhancements in infrared luminosity, in LIR/LB, and in LIR/LHα. The IR flux is well correlated with the Hα and blue fluxes for both the interacting and isolated galaxies. Unique to the interacting sample is a class of very luminous systems which have unusually high LIR/LB values. The average 60–100 µm color temperatures of the interacting galaxies are higher than those of the isolated disk galaxies.
Magnetospherically Mediated Accretion in Classical T Tauri Stars

Observational evidence suggests that disk accretion in low mass stars is mediated by the stellar magnetosphere in the inner few stellar radii of a star/accretion disk system. A strong stellar field appears to disrupt the inner disk and channel accreting material in a funnel flow toward the stellar surface. It is possible that coupling between the stellar magnetosphere and the inner accretion disk plays a profound role in the evolution of a forming star, regulating its spin, establishing its initial angular momentum, and launching the ubiquitous accretion-driven outflows which are the subject of this symposium. Although the evidence that forming low mass stars undergo magnetospherically mediated accretion is considerable, there are a growing number of challenges to this paradigm which require close observational scrutiny.
Effect of curvature on the turbulence of a two-dimensional jet

An experimental study is presented which details the turbulence characteristics of a two dimensional offset jet. A single offset ratio (height of the nozzle above the solid parallel wall by nozzle width) of seven is used with a nozzle Reynolds number of 15,000. Measurements are presented in the preattachment jet region made with a dual frequency shifted laser Doppler anemometer. The relative strain rates resulting from curvature on the upper and lower sides of the jet are determined and their effects on the r. m. s. fluctuating velocity components are presented.
Mineralization of surfactants by the microbiota of submerged plant detritus.

Abstract In wetlands and canopied bodies of water, plant detritus is an important source of carbon and energy. Detrital materials possess a large surface area for sorption of dissolved organics and are colonized by a large and diverse microbiota. To examine the biodegradation of surfactants by these microorganisms, submerged oak leaves were obtained from a laundromat wastewater pond, its overflow, and a pristine control pond. Leaves were cut into disks and incubated in sterile water amended with 50 μg of 14C-labeled linear alkylbenzene sulfonate (LAS), linear alcohol ethoxylate, stearyltrimethyl ammonium chloride, distearyldimethyl ammonium chloride, benzoic acid, or mixed amino acids per liter. Sorption of the test compounds to the detritus and evolution of 14CO2 were followed with time. All of the compounds sorbed to the detritus to various degrees, with LAS and stearyltrimethyl ammonium chloride the most sorptive and benzoic acid the least. All compounds were mineralized without a lag. With leaves from the laundromat wastewater pond, half-lives were 12.6 days for LAS, 8.4 days for linear alcohol ethoxylate, 14.2 days for stearyltrimethyl ammonium chloride, 1.0 days for benzoic acid, and 2.7 days for mixed amino acids. Mineralization of LAS and linear alcohol ethoxylate by control pond leaves was slower and exhibited an S-shaped rather than a typical first-order pattern. This study shows that detritus represents a significant site of surfactant removal in detritus-rich systems.
Feasibility and acceptability of a decision aid designed for people facing advanced or terminal illness: a pilot randomized trial.

Background Patients nearing the end of their lives face an array of difficult decisions. Objective This study was designed to assess the feasibility and acceptability of a decision aid (DA) designed for patients facing advanced or terminal illness. Design We conducted a pilot randomized clinical trial of Health Dialog’s Looking Ahead: choices for medical care when you’re seriously ill DA (booklet and DVD) applied to patients on a hospital-based palliative care (PC) service. Setting University of Colorado Hospital – December 2009 and May 2010. Participants All adult, English-speaking patients or their decision makers were potentially eligible. Patients were not approached if they were in isolation, did not speak English or if any provider felt that they were not appropriate because of issues such as family conflict or actively dying. Intervention All participants received a standard PC consultation. Participants in the intervention arm also received a copy of the DA. Measurements Primary outcomes included decision conflict and knowledge. Participants in the intervention arm also completed an acceptability questionnaire and qualitative exit interviews. Results Of the 239 patients or decision makers, 51(21%) enrolled in the trial. The DA had no significant effect on decision conflict or knowledge. Exit interviews indicated it was acceptable and empowering, although they wished they had access to the DA earlier. Conclusions While the DA was acceptable, feasibility was limited by late-life illness challenges. Future trials of this DA should be performed on patients earlier in their illness trajectory and should include additional outcome measures such as self-efficacy and confidence.
21st Century Africa as an 'Arc of (In)Stability': U.S. And African Economic, Security, and Development Policies Advanced Through U.S. Africa Command Initiatives

This Article will survey the significant legal, political, and operational challenges that US Africa Command (AFRICOM) has already encountered in its relatively short existence, the challenges which lie ahead for AFRICOM, and why AFRICOM will need to further adapt its cooperation with African allies and quantify 'value-added' capabilities if it is to successfully provide and promote allied capabilities. Part 1 will examine Africa as an 'arc of instability,' while Part 2 will describe how U.S. centralized diplomatic and political strategy led to the creation of AFRICOM and the advancement of both U.S. and African economic, security, and development policies. The impact of the 'resourcing-to-requirements' differential (or the disparity in the resources AFRICOM has versus what it must do with them) is discussed in Part 3. The uncertainty created by this U.S. action, as well as its implications on future humanitarian efforts in the region is explained in Part 4, with further discussion on how this perceived uncertainty will affect African and non- African nations’ reactions to AFRICOM in Part 5. Finally, what African nations will do about and with AFRICOM now and in the future is described in Part 6. This Article, therefore, addresses the issues and obstacles AFRICOM is likely to encounter, and attempts to discover the potential solutions offered by law and policy that would aid the organization in successfully accomplishing its stated missions, and advancing an 'arc of stability' in Africa.
Biochemistry and molecular biology of amyloid beta-protein and the mechanism of Alzheimer's disease.

Publisher Summary This chapter reviews the emerging understanding of the causes and mechanism of Alzheimer's disease (AD) that has developed and what it is ultimately likely to mean for treating patients. Major insights into the pathobiology of both AD and the frontotemporal dementias have been derived from the original compositional analyses of the amyloid plaques and neurofibrillary tangles. The chapter explores that Neuritic plaques contain extracellular deposits of the amyloid b-proteins (Ab) surrounded by dystrophic axons and dendrites, activated microglia and reactive astrocytes. A portion of the Ab in these deposits exists in the form of insoluble, 8–10 nm amyloid fibrils, but these are intermixed with complex arrays of smaller filamentous as well as non-fibrillar forms of the peptide. In the future, one can envision that humans reaching their 50s or beyond will be offered a specific risk-assessment profile to determine their likelihood of developing AD. Based on further epidemiologic experience with such assessment measures in large populations of healthy elderly, mild cognitive impairment and AD subjects, it should be possible to estimate—first crudely and later more accurately—the likelihood that an individual will develop AD.
Edge-RMP: Minimizing administrative assignments for role-based access control

Because of its ease of administration, role-based access control (RBAC) has become the norm to enforcing security in most of today's organizations. For implementing RBAC, it is important to devise a complete and correct set of roles. This task, known as role engineering, has been identified as one of the costliest components in deploying RBAC. A key problem with respect to role engineering is that there is no formal metric for measuring the goodness/interestingness of the devised set of roles. Recently, Vaidya et al. [26], formally define the role mining problem (RMP) as the problem of discovering an optimal set of roles from existing user permissions, and analyze its theoretical bounds. Essentially, given a user-permission assignment (UPA), the basic RMP is to discover the user-role assignment relation (UA) and role-permission assignment relation (PA) such that the number of roles required is minimum. In this paper, we present another interesting and useful problem, called the edge-RMP, with a different minimality objective. The edge-RMP, requires the discovery of a complete and correct set of roles such that the discovered |UA|+|PA| is the minimum possible. Minimal |UA|+|PA| is a useful metric as it would minimize the administrative burden since less number of assignments need to be managed. Although the basic-RMP and the edge-RMP appear to be related problems, we demonstrate with concrete examples that they are, in fact, independent of each other. We prove that the edge-RMP is an NP-hard problem by reducing the known “vertex cover problem” to the decision version of the edge-RMP. Another important contribution of this paper is to provide a binary integer programming solution to this problem by showing that the edge-RMP can be formulated in that form. As a result, one can directly borrow existing implementation solutions for binary integer programming and guide further research in this direction. We also propose a heuristic solution for large scale problems, and experimentally validate our algorithm.
Older adult osteoarthritis pain management: Results from the 2008 National Ambulatory Medical Care Survey

Purpose: To describe practitioners’ prescription of recommended initial osteoarthritis (OA) pain treatments for older adults. Data sources: A secondary data analysis was conducted with the 2008 National Ambulatory Medical Care Survey (NAMCS) that was completed by practitioners in ambulatory medical care settings. Of the 28,741 office visits, 9314 were by adult patients age 60 or older, and 871 of those visits involved a painful joint. Only 128 were also by people with practitioner-documented OA. Of those 128 visits, 21 (16.1%) were prescribed exercise and/or acetaminophen and were not prescribed non-steroidal anti-inflammatory agents (NSAIDS). No complementary alternative medical treatments were prescribed. Older adults with and without documented OA had a mean of at least four office visits with the practitioner during the past year. Conclusions: OA may be under-diagnosed, under-reported, or overshadowed by co-morbid medical conditions. Older adults with persistent OA pain are at increased risk for adverse events from prescribed NSAIDs. Safe and effective multimodal pain treatments need to be prescribed for older adults with persistent OA pain. Implications for practice: Referral to a rheumatologist or pain management specialist should be considered when pain intensity and/or pain interference with daily activities remains moderate or greater.
Chapter 17 Voltage-Sensitive Sodium Channels: Molecular Structure and Function

Publisher Summary The improvement of techniques for correlating selective chemical modifications of the protein structure with functional behavior should provide an important avenue for dissecting the mechanisms of gating, conductance, selectivity, and sensitivity to neurotoxins and drugs. These methods are likely to be an important complement to site-directed mutagenesis studies. Voltage-sensitive Na channels are conformationally regulated molecules. Classical conformational mechanisms have involved allostery in enzymes and in binding proteins, such as hemoglobin. Allosteric mechanisms have been historically studied in symmetrical oligomeric proteins, in which the binding of a substrate or effector ligand causes a cooperative change in conformation and a resultant shift in catalytic efficiency or binding affinity.
Conformational Changes of Na,K-ATPase Necessary for Transport

Publisher Summary This chapter discusses the conformational changes of Na, K-ATPase necessary for transport. Two major questions concerning the structure and mechanism of the Na, K-ATPase have been debated for the past several years: does ATP-driven Na/K exchange across the membrane require an interacting dimeric protein structure and do Na + and K + ions occupy the same set of binding sites in a consecutive fashion, or do two sets of binding sites simultaneously exist on the two sides of the membrane? If a basic principle used in developing kinetic models to structural considerations, then it is assumed that the protein has no interacting sites and has only one set of monovalent cation binding sites, until structural or kinetic evidence proves otherwise. The reasons for proposing that an interacting dimeric structure is required for transport were based primarily on observations: (1) all tightly binding ligands were found to bind to one site per 250,000 daltons of purified protein and (2) in addition to the high-affinity ATP site observed in binding experiments, a low-affinity ATP site was observed kinetically. The steady-state equation for the mechanism is determined to verify that all kinetic data reported in the chapter can be explained by a single ATP site whose affinity changes with time.
CpG Oligonucleotides Enhance Proliferative and Effector Responses of B Cells in HIV-Infected Individuals

Stimulation through TLR represents a new therapeutic approach for enhancing Ab responses to vaccination. Considering that Ab responses are decreased in HIV disease and that B cells express TLR9 and respond to TLR9 agonists, we investigated the responsiveness of B cell subpopulations from HIV-infected and uninfected individuals to the TLR9 agonist CpG oligonucleotide type B (CpG-B) in the presence and absence of BCR ligation and T cell help (CD40L). CpG-B was equally effective in stimulating the proliferation of naive B cells of HIV-infected individuals and HIV-negative individuals, and, when combined with BCR and CD40 ligation, cytokine secretion by naive B cells was also comparable in HIV-infected and uninfected individuals. In contrast, CD27 + memory/activated B cells of HIV-infected individuals with active disease were less responsive to CpG-B in terms of proliferation and cytokine secretion when compared with CD27 + B cells of HIV-negative and HIV-infected individuals whose viremia was controlled by antiretroviral therapy. These findings suggest that despite abnormalities in memory B cells of HIV-infected individuals with active disease, naive B cells of HIV-infected individuals, irrespective of disease status, can respond to TLR9 agonists and that the incorporation of such agents in vaccine formulations may enhance their Ab responses to vaccination.