cssi/SciSciGPT-SciSciNet huggingface dataset:
Disorders of purine and pyrimidine metabolism

Nucleotide metabolism is directly linked to cellular homeostasis as it is essential for physiological processes such as carbohydrate metabolism, oxidative phosphorylation, essential nucleotide biosynthesis, and signal transduction. The consequences of perturbations in purine and pyrimidine metabolism represent a diverse collection of disorders, differing in both their clinical manifestations and underlying molecular mechanisms. These disorders originate from abnormal enzymatic function in one of four molecular modules: de novo synthesis, catabolism and metabolite recycling, and excretion. Aberrations in these processes result in the depletion of nucleotides or accumulation of toxic intermediates, leading to various pathological outcomes. Because of the potential to intervene therapeutically in some of these disorders, early and accurate diagnosis is vital for diagnosis and treatment, as well as family and reproductive counseling. The mainstay of diagnosis is the analysis of blood and urine purines and pyrimidines. In addition, extracts from erythrocytes may be used to analyze nucleotide profiles for clinical purposes. After confirming a diagnosis, management options are strategically focused on decreasing the overproduction of related metabolites that have an acquired toxicity or replacement of those that are deficient. This chapter provides details of known disorders of purine and pyrimidine metabolism, their clinical presentations, diagnostic methodology, and current treatment options.
Expanding the inclusion criteria for nonoperative management of uncomplicated appendicitis: Outcomes and cost.

Abstract Background Carefully selected children with early appendicitis may be managed nonoperatively. However, it is unknown whether nonoperative management (NOM) is applicable to all patients with uncomplicated appendicitis. The purpose of this study was to evaluate the outcomes of NOM of uncomplicated appendicitis with expanded inclusion criteria. Methods A prospective, nonrandomized patient-preference study comparing NOM versus laparoscopic appendectomy (LA) was performed in children with radiographic/clinical evidence of uncomplicated appendicitis. Results Demographics, laboratory values, and clinical presentation were similar between the NOM (n=51) and LA (n=32) groups. Initial failure rate was 31%. The outcomes were similar between groups, except that NOM had fewer days of pain medication. Patients who failed NOM had a longer duration of symptoms prior to admission. Patients with appendicolith had a failure rate of 50% compared to 24% without appendicolith. The recurrence rate was 26%. Overall, 51% avoided appendectomy. Costs were similar between NOM and LA. Conclusions When expanding the inclusion criteria for children with presumed uncomplicated appendicitis, NOM was associated with high failure and recurrence rates. These high rates may be because of the inclusion of patients with complicated appendicitis and patients with an appendicolith. Even in this setting of less-restrictive exclusion criteria, NOM remained cost neutral. Level of evidence LEVEL II (Treatment Study: Prospective Comparative Study).
Atmospheric deposition, mass balances, and processes regulating streamwater solute concentrations in mixed-conifer catchments of the Sierra Nevada, California

Solute concentrations in atmospheric deposition and stream water were measuredfrom 1984 through 1993 to determine the fate and mobility of solutes in twogauged mixed-conifer catchments (Tharp's and Log creeks) located in theSierra Nevada, California. The two catchments contain mature forest standsdominated by Abies concolor (white fir), Sequoiadendron giganteum (giantsequoia), Abies magnifica (red fir) and Pinus lambertiana (sugar pine).Ammonium, Cl-, Ca2+ and NO- 3were highest in concentration of the solutes measured in wet deposition;bulk deposition was highest in SO2- 4, NH+ 4,Cl- and H+. Net retention ofH+, NO3 -, NH4 +,SO4 2- and Cl- occurred in both catchments.Discharge was dominated by spring snowmelt with the largest export yieldsfor acid neutralizing capacity (ANC), SiO2, andCa2+. Export yields of H+,NO3 -, NH4 + and PO4 3-were relatively small (0.5 kg ha-1 y-1).Discharge-concentration relationships for ANC, SiO2,Na+, K+, Ca2+ andMg2+ were inverse and their concentrations in stream waterwere primarily influenced by discharge and annual differences in the relativecontributions of snowmelt and groundwater. The mobility of these solutes iscontrolled by the rates of mineral weathering and ion exchange. The positiverelationship of SO4 2- concentration with increasingdischarge suggests that atmospherically deposited SO4 2-is temporarily stored and that its release is controlled by the extent of soilwater flushing.
BioCON: Studying the Interactions Between Biodiversity, Elevated CO2, and N Deposition

Abstract The biodiversity, carbon dioxide, and nitrogen (BioCON) experiment was a free-air CO 2 enrichment (FACE) study designed to explore the interactions between plant species diversity, nutrient balances, and productivity. Unlike many other FACE studies, which study the effect of CO 2 enrichment alone on ecosystem processes, BioCON experimentally manipulated nitrogen (N) deposition and biodiversity to study the interacting effects of elevated CO 2 , N deposition, and biodiversity on productivity. The results of BioCON suggest that elevated CO 2 increases ecosystem productivity primarily by altering plant physiological responses, while elevated N increases productivity by changing the abundance of plant species. The results also indicate that productivity and diversity may not always covary in time. The interactions between the drivers in this experiment emphasize the importance of long-term, whole-ecosystem manipulations of multiple factors for understanding the interactive effects between biotic and abiotic ecosystem processes.
Alcohol-related problem behaviors among Latin American immigrants in the US.

Abstract Background Prior research indicates that Latino immigrants are less likely than US-born individuals to use alcohol and meet criteria for an alcohol use disorder. However, our understanding of alcohol-related problem behaviors among Latino immigrants remains limited. We report the prevalence of alcohol-related problem behaviors among Latino immigrants vis-a-vis the US-born and examine the relationship between alcohol-related problem behavior and key migration-related factors and injury/receipt of emergency medical care. Methods The data source used for the present study is the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC-III, 2012–2013), a nationally representative survey of 36,309 civilian, non-institutionalized adults ages 18 and older in the US. Logistic regression was employed to examine the relationship between immigrant status and key outcomes. Results Foreign-born Latinos were less likely to report one or more alcohol-related problems compared to US-born Latinos (AOR = 0.41, 95% CI = 0.33–0.50) and the US-born general population (AOR = 0.38, 95% CI = 0.32–0.46). Latino immigrants arriving as children were, compared to those arriving later in life, significantly more likely to report alcohol-related problem behaviors, and experiences of discrimination were linked with greater risk of alcohol-related problem behavior as well. Latino immigrants reporting recurrent injury/emergency medical care utilization were more likely to report alcohol-related problem behavior. Conclusions Latino immigrants are significantly less likely than US-born Latinos and the US-born general population to operate a vehicle under the influence of alcohol, take part in risky behaviors or fight while drinking, or to be arrested due to alcohol consumption.
Rate and Time-Dependent Failure: Mechanisms and Predictive Models

No text on polymer science and viscoelasticity is complete without a discussion of time-dependent failure and just as with other structural materials, failure must be defined. In this chapter, only failure by a creep to yield or a creep to rupture (separation) will be considered. We will address both the mechanisms of deformation that often precede these types of failures as well as modeling to describe this behavior. The primary focus will be on one-dimensional models but many of the models discussed have been or can be extended to three-dimensions. The procedures to be discussed are not new and are relatively easy to use by the design engineer to make estimates of the time for either yielding or rupture to occur. While no discussion of either viscoelastic fracture mechanics or fatigue crack growth will be given these are very important topics and the reader is referred to Knauss (1973, 2003) for the former and to Kinloch and Young (1983) for the latter for an in-depth discussion of these topics. Fracture based approaches for prediction of time to failure work best when a crack of a known size exists. The same is true for fatigue as a relation between crack growth rates and time to failure can be established. Other approaches provided by damage mechanics (Krajcinovic 1983) and viscoplasticity (Lubliner 1990) provide a more rational but highly mathematical approach to damage and/or failure evolution for three-dimensional stress states and are perhaps best suited for numerical procedures such as the finite element method. Here we restrict ourselves to simpler, analytic approaches to introduce the fundamental issues.
Immigrant women's health: Infectious diseases--Part 1. Clinical assessment, tuberculosis, hepatitis, and malaria.

Detection and treatment of infectious diseases and appropriate patient education are a crucial part of the screening of newly arrived immigrants.1,2 This is important for the health of the individual, the family, and the general public. Although some screening will often have taken place before a person's arrival in the United States, screening methods and infectious disease treatments vary considerably from 1 region to another and deserve a thorough review. In this article, I discuss the medical history and physical examination in relation to infectious diseases and review specific diseases and topics in more detail. The infectious disease screen is particularly important in situations such as pregnancy or the contemplation of pregnancy, blood donation, and the administration of immunosuppressive medications. Wilson's A World Guide to Infections, a comprehensive and invaluable reference, should be immensely helpful to any clinician who treats immigrants.1
GOAT and the Regulation of Energy and Glucose Homeostasis

Ghrelin is the only known circulating hormone that potently stimulates food intake and adipogenesis in rodents and humans. Through a unique posttranslational modification, the premature ghrelin peptide is acyl-modified with a medium-chain fatty acid at the serine-3 position by ghrelin-O-acyl transferase (GOAT) to form acyl ghrelin. This step is necessary to activate ghrelin’s only known receptor, the growth hormone secretagogue receptor 1a, also known as the ghrelin receptor. GOAT activity is highly influenced by the availability of dietary lipids; dietary lipids serve as a direct GOAT substrate for ghrelin acylation. Further, GOAT gene expression and circulating acyl ghrelin levels are decreased after long-term starvation when dietary lipids are absent. These findings suggest that the ghrelin-GOAT system plays an important role in linking nutrient availability with endogenous regulation of energy homeostasis, especially adipogenesis. Recent data further suggest that GOAT is a significant factor in the regulation of glucose homeostasis as specific pharmacological GOAT inhibition improves glucose tolerance and insulin secretion. During caloric restriction, the ghrelin-GOAT system may play an important role for the maintenance of physiological range glucose levels by stimulating the secretion of growth hormone.
Disentangling orthorexia nervosa from healthy eating and other eating disorder symptoms: Relationships with clinical impairment, comorbidity, and self-reported food choices

Abstract Background Orthorexia nervosa (ON) is characterized by obsessions about eating healthily and rigid adherence to a perceived healthy diet. This study uses the Eating Habits Questionnaire to investigate the relationship of ON symptoms with self-reported food intake, eating-related impairment, obsessive compulsive disorder symptoms (OCD), gender, and BMI while controlling for other eating disordered symptoms. The aim of this study is to provide further evidence for the construct of ON as distinct from other forms of disordered eating. Methods The sample consisted of 449 adults recruited on Amazon's Mechanical Turk. Self-reported symptoms of currently recognized eating disorders (anorexia and bulimia nervosa, AN/BN, avoidant/restrictive food intake disorder, ARFID) were statistically controlled in correlational analyses and MANCOVA exploring the relationship of ON domains to comorbidity, eating behavior, gender, and weight. Results Confirmatory factor analysis supported a three-factor solution for the EHQ, with factors representing normative healthy eating behaviors (“behaviors”), positive feelings associated with healthy eating (“feelings”), and interference/problems from rigid healthy eating (“problems”). Overall ON symptoms were more strongly related to AN/BN than to ARFID. Of the subscales, only Problems was related to other eating disorder symptomatology. Controlling for other eating disorder symptoms, overall ON symptomatology was not related to clinical impairment from eating or OCD, although it was related to higher self-reported intake of fruits/vegetables and lower intake of discretionary foods. When other eating disordered symptoms and ON domains were statistically controlled, Problems was related to clinical eating impairment, OCD symptoms, and higher intake of both fruits/vegetables and discretionary foods. Conclusions The Problems scale of the EHQ appears to capture disordered eating symptomatology that is distinct from other eating disorders and from normative healthy eating behaviors, consistent with descriptions of ON.
Data-driven lean Management for Distribution Network

This paper proposes a concept of “data-driven, lean-oriented and closed-loop” management for distribution network and explain how to implement this kind of management, as shown in fig. 1Firstly, a big data platform is constructed to integrate and combine the multi-source data. Secondly, big data analysis technologies such as data mining, machine learning and data visualization are applied to solve problems in distribution network production. For example, accurate location of the fault can be found with help of multisource information from different devices and systems. And we can also be aware of the risk points in distribution network through history data analysis. Finally, this Paper explains how to promote lean management of distribution network in the fields of asset, operation, maintenance and investment based on the big data platform and big data analysis methods. In addition, the feedback procedure sets up a bridge between application and data collecting, which further improve the data quality. Those management measure have been piloted in several cities in Jiangsu. The result proves that they can improve power supply reliability and reduce operating costs significantly. Two practical cases are given to show how they work.
Shooting Rubber Bands: Two Self-Similar Retractions for a Stretched Elastic Wedge

Stretching and shooting rubber bands is a familiar experience for both children and adults, yet the initial dynamics are so quick that they are generally missed. When a cut elastic strip is stretched from its end and suddenly released, the dynamics depend on a balance of stretching and inertia. However, when a rubber band is stretched, a region of high curvature is created and it is unclear how this curvature affects the dynamics. Here, we demonstrate that during the retraction of a circular rubber band, a wavelength develops at the rear which increases in size as time progresses. Through a combination of experiments and modeling, we investigate the speed at which the back of the elastic retracts and observe a self-similar shape that depends on stretching, inertia, and bending. These retraction dynamics illuminate how a rubber band can pass by a thumb when discharged without hitting it.
Combined menin and EGFR inhibitors synergize to suppress colorectal cancer via EGFR-independent and calcium-mediated repression of SKP2 transcription

Menin is a nuclear epigenetic regulator that can both promote and suppress tumor growth in a highly tissue-specific manner. The role of menin in colorectal cancer, however, remains unclear. Here, we demonstrate that menin was overexpressed in colorectal cancer and that inhibition of menin synergized with small-molecule inhibitors of EGFR (iEGFR) to suppress colorectal cancer cells and tumor xenografts in vivo in an EGFR-independent manner. Mechanistically, menin bound the promoter of SKP2, a pro-oncogenic gene crucial for colorectal cancer growth, and promoted its expression. Moreover, the iEGFR gefitinib activated endoplasmic reticulum calcium channel inositol trisphosphate receptor 3 (IP3R3)-mediated release of calcium, which directly bound menin. Combined inhibition of menin and iEGFR-induced calcium release synergistically suppressed menin-mediated expression of SKP2 and growth of colorectal cancer. Together, these findings uncover a molecular convergence of menin and the iEGFR-induced, IP3R3-mediated calcium release on SKP2 transcription and reveal opportunities to enhance iEGFR efficacy to improve treatments for colorectal cancer. SIGNIFICANCE: Menin acts as a calcium-responsive regulator of SKP2 expression, and small molecule EGFR inhibitors, which induce calcium release, synergize with Menin inhibition to reduce SKP2 expression and suppress colorectal cancer.
Implementation of a Dedicated Education Unit Model for ADN Students in a Rural Primary Care Setting.

Background Dedicated education unit (DEU) clinical education models are an innovative, evidence-based approach to create effective learning environments for students. These models have been implemented primarily in acute care settings. Problem The gap between nursing education and clinical practice in rural health care settings is a growing concern, compounded by a nursing faculty shortage and decreased availability of clinical sites. Approach A descriptive study design was used to assess the outcomes of a DEU model of clinical practice with associate degree nursing students in a rural primary care clinic, using registered nurses (RNs) who were prepared as clinical nurse teachers. Outcomes Associate degree nursing students experienced the RN role in primary care, worked with nurses who wanted to teach them, and improved their nursing skills. Conclusions The DEU model is a positive clinical teaching pedagogy for students and staff nurses.
Functional Imaging of Pediatric Musculoskeletal Tumors

Musculoskeletal malignancies are among the more common solid tumors of childhood. These include osteogenic sarcoma, or osteosarcoma, the Ewing family of tumors, and rhabdomyosarcoma. Imaging studies, including 18F-FDG PET and PET/CT, are used for initial staging, assessing the response to therapy, and surveillance for recurrent disease. In initial staging, identification of distant metastases is a common need with all three tumor types. In addition to prognostic implications, identification of distant disease can guide therapy.
Social capital – a topsoil for democracy

Political theorists are familiar with the proposition that social capital in the form of trust, membership in voluntary organizations, and community engagement, is conducive to democracy. Corrobora...
Effects of Parental Childhood Abuse on Daily Stress Processes in Adulthood

Extensive evidence suggests that exposure to childhood abuse can lead to harmful health effects across a lifetime. To contribute to the literature, the current study examined whether and how a history of parental childhood abuse affects exposure to and severity appraisal of daily stressors in adulthood, as well as emotional reactivity to these stressors. We analyzed 14,912 daily interviews of 2,022 respondents from the second wave of the National Study of Daily Experiences. Multilevel modeling was utilized to analyze nested data, in that each person provided repeated measures of daily experience for eight consecutive study days. Results showed that more frequent experience of maternal childhood abuse was associated with more severe appraisal of daily stressors. In addition, adults with more frequent maternal childhood abuse exhibited greater emotional reactivity to daily stressors. The current study provides evidence that a history of parental childhood abuse may serve as a vulnerability factor in the process of experiencing and responding to stressful events encountered in daily life. Future research should further explore the long-term health effects of daily stress and emotional experience among adults with a history of parental childhood abuse. Interventions for these adults should focus on promoting emotional resilience in the face of daily stress.
Stacked Hybrid Discrete Choice Models for Airline Itinerary Choice

This study develops a methodology to train and apply a hybrid stacked discrete choice model for airline itinerary choice. This stacked model framework includes a data-driven component (i.e., gradie...
Within-language lexical interference can be resolved in a similar way to between-language interference

This study asks if monolinguals can resolve lexical interference within a language with mechanisms similar to those used by bilinguals to resolve interference across languages. These mechanisms are known as bilingual language control, are assumed to be at least in part top-down, and are typically studied with cued language mixing, a version of which we use here. Balanced (Experiment 1) and nonbalanced Spanish-English bilinguals (Experiment 2) named pictures in each of their languages. English monolinguals from two different American cities (Experiments 3 and 4) named pictures in English only with either basic-level (e.g., shoe) or subordinate names (e.g., sneaker). All experiments were identically structured and began with blocked naming in each language or name type, followed by trial-level switching between the two languages or name types, followed again by blocked naming. We analyzed switching, mixing and (introduced here) post-mixing costs, dominance effects and repetition benefits. In the bilingual experiments, we found some signs of dominant deprioritization, the behavioral hallmark of bilingual language control: larger costs for dominant- than for nondominant-language names. Crucially, in the monolingual experiments, we also found signs of dominant deprioritization: larger costs for basic-level than for subordinate names. Unexpectedly and only in the monolingual experiments, we also found a complete dominance reversal: Basic-level names (which otherwise behaved as dominant) were produced more slowly overall than subordinate names. Taken together, these results are hard to explain with the bottom-up mechanisms typically assumed for monolingual interference resolution. We thus conclude that top-down mechanisms might (sometimes) be involved in lexical interference resolution not only between languages but also within a language.
Effects of usEPs on Plasma Membranes—Pores, Channels, and Repair

Receptors, channels, glycoprotein, and transport proteins, among other integral proteins, load the plasma membrane lipid bilayer, which receives reinforcement from cytoskeletal filaments as the boundaries of cellular life. Early studies suggested that usEPs did not induce plasma membrane permeabilization until relatively high amplitude conditions. As will be discussed here and elsewhere, this was because the usEP-induced plasma membrane pores were so small that they did not allow entry of propidium iodide, a commonly used marker for permeability, or calcein exit from the cell. The plasma membrane contained nanoelectropores or nanopores, so-called because they were ~1 nm in diameter. These lipid nanopore structures exhibited complex conductances similar to classic pores, which are common in protein structures. Another finding presented some confounding information regarding plasma membrane phosphatidylserine (PS) externalization, commonly used as a marker for apoptosis. usEPs “pulled” PS through these nanopores. Now PS externalization was an ambiguous marker for apoptosis. Although plasma membrane lipids were clear usEP targets, plasma membrane channels were also targets for usEPs. As will be discussed, these effects could be due indirectly to nanopore formation or possibly directly on the channels themselves, although more evidence for direct effects is necessary. In any event, patch-clamp techniques provided new, exciting, and valuable information about usEP effects on plasma membranes. As might be expected, cells have mechanisms that confront nanopore formation and other possible usEP-induced injuries, which will be presented. Finally, in relatively uncharted territory, usEPs were also shown to affect redox systems in plasma membranes as electron carriers. Although usEPs are unique for their effects on intracellular structures and functions, their impact on the plasma membrane has provided a wealth of information about how they can be used as tools in biology and medicine.
A Highly Reflecting Microwave Plasma Mirror

Lately there has been a strong interest in developing efficient plasma mirrors to reflect microwave beams1. This interest has arisen mostly from the possibility to redirect radar and satellite signals by the interaction with a plasma grating created in the ionosphere. Since the index of refraction of a plasma medium can be considerably less than 1, high reflectivities should be expected. The excitation of these gratings, however, depends on the efficiency of coupling between the plasma and the interference pattern of the two pump waves that are writing the grating. An efficient coupling is in most cases difficult to achieve which results in a low efficiency reflecting grating.
Land cover influences dietary specialization of insectivorous bats globally

Land-use changes are a leading cause of biodiversity loss and ecosystem service degradation worldwide, but these changes do not affect all organisms equally. Understanding factors influencing resistance to environmental change is vital for informed conservation. In particular, dietary generalists may withstand environmental change better than specialists due to their ability to exploit variable resources. Bats are voracious insectivores, but vary widely in their degree of dietary specialization. Here, we analyze the effect of land cover and morphology on dietary diversity and the two most common prey items on which bats specialize (Lepidoptera and Coleoptera), selecting important independent variables using phylogenetic generalized least squares and model selection. Dietary diversity increased with increasing amount of cropland near the study area, consumption of Lepidoptera decreased with increasing habitat diversity, and consumption of Coleoptera decreased with increasing distance from the equator. Biodiversity (and hence, prey diversity) is expected to decrease with agricultural intensity, but the observed pattern suggests dietary specialists may avoid agricultural habitats due to lack of preferred prey. Dietary specialists may thus be increasingly at risk as agricultural intensity increases around the world, and it is essential that we continue to document their ecological roles and the services they provide to society.
Fates of Assailants of U.S. Presidents

Public outrage has been mounting in recent years over the increasing number of violent crimes and assassination attempts. Before the 1982 Hinckley verdict, criticisms over merits of the insanity defense were escalating. Immediately afterwards some inaccurate news reports and hyperbole by public figures added to the popular perception that the insanity defense and psychiatric testimony have allowed notorious offenders more favorable dispositions, or perhaps even to go “scot-free.” Systematic review of fates of prior Presidential assailants demonstrates that both legal and extralegal consequences for their violent acts have been severe. Some inferences are discussed.
Strange behavior in infinite and transfinite networks

This paper gathers together and explains physically a variety of queer and paradoxical phenomena exhibited by infinite and transfinite networks. >
Multi-wavelength intra-peak phase separations in pulsed emissions from the Crab and the Vela pulsars

The Crab and the Vela pulsars were observed to emit pulsed radiation in the radio, optical, X-ray and gamma ray windows of the electromagnetic spectrum. In all cases the emission appears in two peaks, except in the case of radio emission from the Vela pulsar which is single peaked. With accurate peak position determinations made possible by recent observations, it is interesting to see if the intra-peak separations at various wavelengths across the electromagnetic spectrum bear any relation to each other. We report here an emerging trend of a monotonic decrease of the intra-peak separation with energy. The rate of decrease is faster in the case of the Vela pulsar than in that of the Crab pulsar. Even the case of single peaked radio emission by the Vela pulsar can be viewed as being consistent with this trend. These trends provide both an opportunity and a challenge to realistic modelings of pulsed emissions by these objects.
Testing the Sprint Curve Model using the 150m Bailey-Johnson Showdown

Recently, a simple model was derived to account for a sprinter's energy loss around a curve, based on previous sprint models for linear races. This paper offers a quick test of the model's precision by comparing split times from Donovan Bailey's 150m ``Challenge of Champions'' race at Skydome on June 1st, 1997. The discrepancy in the track configuration which almost prompted Bailey to drop from the race is also addressed.
Communicating across cultures: suggested teaching strategies.

Context: Quality healthcare for diverse populations requires providers that understand the impact of culture on health and health seeking behaviors. Recruiting individuals from diverse cultures into healthcare professions facilitates this understanding. Although nursing education programs have been successful in recruiting such individuals, they often experience difficulties communicating with faculty and patients, which contributes to attrition from their first clinical course. Communicating Across Cultures is an innovative learning experience at our school to facilitate achievement of clinical competencies in the first nursing course. The purpose of this paper is to describe the teaching strategies used in this course that have increased achievement of clinical competencies and decreased the attrition rate of students from diverse cultures at our school. Suggested Teaching Strategies: First, assessing the students' specific communication difficulties guides what learning objectives and content are appropriate. Second, an immersion experience immediately before students begin their first clinical course provides experiential learning suited to acquiring new communication styles. Third, the experience and subsequent reinforcement are facilitated by faculty with expertise in teaching communication skills and with guiding the learning experiences of students from diverse cultures. Fourth, delineation of eligibility criteria allows students to self-identify their need to participate. Finally, an evaluation plan provides information to help make decisions about subsequent implementation of the learning experience.
Studies on the distribution of free carnitine and the occurrence and nature of bound carnitine.

Abstract The distribution of carnitine in various tissues of the rat was investigated, using modifications of existing assays. Muscle showed about 120–180 μ./g. wet weight; brain, 20 μg.; liver 60–90 μg.; testes, 115 μg. Various treatments with organic solvents and acids released no increased amounts of carnitine. All carnitine was dialyzable. No “bound carnitine,” therefore, was detectable in mammalian tissue. This result was confirmed by injection of labeled carnitine, using a radiochemical assay, in combination with the chemical assay. Developing chick embryos showed a great increase in carnitine between the 12th and 16th day (about 175 and 850 μg. per whole egg, respectively). It was found that yolk sac contained about 40–50% of the carnitine of whole egg, and that some of this, about 20–45%, was in a bound form, released by acid treatment and nondialyzable. Specific extraction procedures, followed by hydrolysis, showed this “bound carnitine” to be combined in phospholipid. This finding was confirmed with labeled carnitine. Labeled phospholipid was extractable from the yolk sac, and was purified by silicic acid chromatography. A labeled carnitine-contaming phospholipid emerged with the lecithin fraction. The hypothesis is proposed that this material is phosphatidylearnitine.
On the Extension of Thermodynamics to General Relativity.

Introduction. The recent interesting article of Lenz(1) on the equilibrium between radiation and matter in Einstein's closed universe makes it desirable to investigate the proper method of extending the ordinary principles of thermodynamics so as to make them hold for considerations in curved space-time where the methods of general relativity must be employed.
The Mirror of Television: A Comparison of Black and White Adolescents' Body Image.

Research has shown differences in the extent of eating-disordered attitudes and behaviors between African American and European American women. However, the extent to which those differences are a result of differences in cognitive processing and exposure of mediated images remains untested. This study tests that notion through the framework of social comparison theory. The sample consists of 145 White and 33 Black females from 2 high schools in 2 medium-sized Midwestern cities. Results indicate that African American girls do respond differently to and are differently affected by thin images than European American girls. However, there are also some similarities between the adolescents that foreshadow a narrowing of the ethnic gap in the development of eating disorders.
Thermal properties of forsterite, including Cv, calculated from αKT through the entropy

Abstract We present several thermodynamic properties for Mg2SiO4 (forsterite) expressed as a function of volume and temperature, including: the entropy, S; the specific heat, CV; the isentropes in V, T space; and the Gruneisen ratio, γ of Mg2SiO4 in V, T space. We use the experimental data on α (thermal expansivity) as a factor of the input, αKT, where KT is the isothermal bulk modulus. In fact, we use αKT vs T at P = 0 up to 1800 K as it was presented by Isaak D. G., Anderson O. L., Goto T. and Suzuki I., J. Geophys. Res. 94, 5895 (1989). Guyot F., Wang Y. and Gillet P. (in preparation) that the thermal pressure (and therefore αKT) is independent of V up to V/V0= 0.9. This allows us to calculate the isochoric entropy, SV = S(V, T),from the input, αKT, over a wide V and T range. The integration of S(V, T)/T with respect to T produces CV(V, T), which we show as isochores on a CV(T) plot. The data on SV are rearranged to produce isentropes—lines of constant entropy in a V, T plot. Using the isentrope data, we calculate γ(V, T) as isochores of γV(T). We compare the α(T) used in this paper with other data on α(T) and discuss the evidence for anharmonicity of Mg2SiO4, as evidenced by the limit imposed on CV by the Dulong and Petit limit. We also compare volume dependencies ( ∂ln CV/∂ln V)T, of CV for MgO and Mg2SiO4 up to 1600K and V/V0= 0.9. We attribute the trend for CV to increase with T above 1600 K for forsterite to anharmonicity.
Teaching operating systems using code review

Learning about operating systems often involves modifying a large and complex code base. Grading student projects can be difficult and time consuming, yet students often do not learn from their programming errors and struggle to understand core operating system concepts. We present GradeBoard, a code review system designed to simplify grading for instructors and enable students to understand and learn from their errors. GradeBoard provides an easy-to-use Web interface that allows instructors to annotate student code submissions with grading comments and scores, and students to discuss the comments and scores with instructors. GradeBoard presents student code changes with syntax highlighting and lets users collapse or expand code sections to provide a desired level of context, making it easier to read and understand student programming project submissions. Comments and scores are easily identifiable by visual cues, improving interaction between instructors and students. We have deployed and used GradeBoard in a large operating systems course involving Linux kernel programming projects. GradeBoard provided robust, easy-to-use functionality for reviewing Linux kernel code changes, improved the instructional staff grading experience, and over 90% of students surveyed indicated that GradeBoard improved their understanding of the kernel programming projects better than other alternatives.
REGULATION OF THE HUMAN NEUTROPHIL NADPH OXIDASE BY THE RAC GTP-BINDING PROTEINS

Recent progress in our understanding of the regulation of the phagocyte NADPH oxidase by the Rac GTP-binding protein(s) has provided the first detailed glimpse into the mechanisms of leukocyte regulation by a small GTP-binding protein. Studies over the past year have indicated that the activity of the NADPH oxidase can be modulated by regulation of the GTP/GDP state of Rac. Proteins exist in leukocytes that are able to modify GTP-binding protein function in this manner, and their activity may be regulated by signals generated upon phagocyte stimulation.
Split-thickness skin grafting in postmastoidectomy revision and in lateral temporal bone resection.

Objectives Use of split-thickness skin grafts (STSG) in revision canal wall-down (CWD) mastoidectomy was compared with STSG in lateral temporal bone resection (LTBR). Study design and setting A retrospective study of 11 patients undergoing revision CWD mastoidectomy and 6 patients undergoing LTBR with STSG in an academic health center setting. Results Successful epithelialization of the mastoid cavity occurred in 9 patients (82%) undergoing CWD mastoidectomy. Subjective success, measured as reduction in complaints of otorrhea, occurred in 10 patients (91%). In the 6 patients who underwent LTBR and STSG successful epithelialization of the temporal bone defect occurred in 5 patients (83%). Conclusions Successful and rapid epithelialization occurred in the revision mastoidectomy cohort as well as in the primary temporal bone resection cohort. Significance Placement of STSG is a useful adjunct in revision CWD mastoidectomy as well as in primary LTBR for cancer.
Accurate localization and relative quantification of arginine methylation using nanoflow liquid chromatography coupled to electron transfer dissociation and drbitrap mass spectrometry

Protein arginine (Arg) methylation serves an important functional role in eucaryotic cells, and typically occurs in domains consisting of multiple Arg in close proximity. Localization of methylarginine (MA) within Arg-rich domains poses a challenge for mass spectrometry (MS)-based methods; the peptides are highly charged under electrospray ionization (ESI), which limits the number of sequence-informative products produced by collision induced dissociation (CID), and loss of the labile methylation moieties during CID precludes effective fragmentation of the peptide backbone. Here the fragmentation behavior of Arg-rich peptides was investigated comprehensively using electron-transfer dissociation (ETD) and CID for both methylated and unmodified glycine-/Arg-rich peptides (GAR), derived from residues 679–695 of human nucleolin, which contains methylation motifs that are widely-represented in biological systems. ETD produced abundant information for sequencing and MA localization, whereas CID failed to provide credible identification for any available charge state (z=2–4). Nevertheless, CID produced characteristic neutral losses that can be employed to distinguish among different types of MA, as suggested by previous works and confirmed here with product ion scans of high accuracy/resolution by an LTQ/Orbitrap. To analyze MA-peptides in relatively complex mixtures, a method was developed that employs nano-LC coupled to alternating CID/ETD for peptide sequencing and MA localization/characterization, and an Orbitrap for accurate precursor measurement and relative quantification of MA-peptide stoichiometries. As proof of concept, GAR-peptides methylated in vitro by protein arginine N-methyltransferases PRMT1 and PRMT7 were analyzed. It was observed that PRMT1 generated a number of monomethylated (MMA) and asymmetric-dimethylated peptides, while PRMT7 produced predominantly MMA peptides and some symmetric-dimethylated peptides. This approach and the results may advance understanding of the actions of PRMTs and the functional significance of Arg methylation patterns.
CHANGES IN SERUM CHOLESTEROL AND CHOLESTEROL ESTERS IN ALLOXAN DIABETIC RABBITS

The effect of diabetes mellitus on the ratio of free to esterified cholesterol of the serum has not been established (Peters and Van Slyke, 1948) although it is generally recognized that disturbances of cholesterol metabolism do occur in this condition. The usuai manifestation is a hypercholesterolemia which does not seem to be related to hyperglycemia, glycosuria, or ketonuria although it is more marked in severe cases of diabetes with a tendency to ketosis and acidosis. In patients controlled either with diet or with insulin, there is usually a normal concentration of serum cholesterol; this is not invariably true as there are several reports of diabetic subjects who continued to have high postabsorptive serum cholesterol levels, even when their diabetes was well controlled (Peters and Van Slyke, 1948). It is difficult to interpret the cause and effect relationship of cholesterol metabolism to clinical diabetes because of the complicated picture of human diabetes.
The People's Two Rhythms: Charles Tilly and the Study of Contentious Politics. A Review Article

In recent years, there has been an "event-ful return" in historical sociology and social history. Using new and swifter computational technologies, social scientists are employing systematic empirical methods to analyze population ecologies, social conflicts, and political struggles. This is no surprise-although the advances in computational technology have raised it to a new level of sophistication. But interpretive social scientists are focusing more on agency and actions too, promising a convergence-after years of growing distancebetween cliometrics and interpretation and between social and cultural history. Nowheree more than in the study of contentious politics does the systematic study of events hold the greatest promise for the return of the actor to social historical practice. For classes of events ranging from revolutions to ethnic conflicts to strikes and protests, students of collective action are enumerating and analyzing events to study the scope and dynamics of social movements. But there is a danger of a new bifurcation: While some, like William Sewell, argue for a re-concentration on Great Events (1996a), others, like Susan Olzak, have used events as quantitative markers for structural processes (1989). Unless we are careful, sociologists working with historical materials and historians interested in social processes will proceed on parallel paths to the study of contentious politics with a wall of mutual ignorance between them. In his recent book, Popular Contention in Great Britain, 1758-1834 (1995), Charles Tilly-who has trodden both paths-works towards a synthesis of quantitative and qualitative, long-term and shorter-term analysis of contention. But it was not always so. In this review, I will trace the progression of Tilly's work on contentious politics from The Vendee in the 1960s through his collaborative books of the 1970s and The Contentious French in the 1980s. I will first sketch the major emerging approaches to contentious politics, which I will call, with Sewell, "event-ful history" and, with Susan Olzak, "event history."' I will then turn to the synthesis of these approaches that I argue Tilly has been moving towards for a number of years. The title of
Fate of labeled n-alkanes in the blue crab and stripped mullet

Results of these studies demonstrate that the blue crab was readily able to take up and discharge labeled n-alkanes, but it was not able to metabolize them. In contrast, it appears that n-alkanes taken up via the digestive tract in mullet are readily metabolized, probably via microorganisms in the gut. More limited metabolism was observed in mullet when n-alkanes were taken up via the gills.
Cardiovascular Status after Repair by Fontan Procedure

Abstract Patients surviving a Fontan operation experience dramatic symptomatic improvement, but concern remains about the long-term results of this operation. The clinical course and postoperative hemodynamic findings in 5 long-term survivors of the Fontan procedure from our institution are presented. Attention is drawn to 3 patients who required reoperation: 1 immediately for residual mild pulmonary stenosis, 1 for late onset complete heart block, and 1 for conduit valve stenosis. Review of our patients and those described in the literature reveals that all have ascites and pleural effusions as a result of high venous pressures but that this is usually a temporary problem. Late onset of obstruction to right atrial emptying has been reported in several patients in addition to ours. This raises serious concerns about the long-term fate of cloth conduits and porcine valves in this application. Although normal sinus rhythm has been thought to be essential for adequate pulmonary perfusion in these patients, it is interesting that several patients have tolerated atrial tachyarrhythmias, junctional rhythms, and even complete heart block without serious ill effects. We conclude that the Fontan procedure is extremely effective in relieving symptoms at an operative risk that is now acceptable, but these patients require very careful long-term follow-up because they are subject to a number of long-term complications.
Chain Length Analysis of ADP‐Ribose Polymers Generated by Poly(ADP‐Ribose) Polymerase (PARP) as a Function of ß‐NAD and Enzyme Concentrations

Bireactant autopoly(ADP-ribosyl)ation of poly(ADP-ribose) polymerase (PARP) (EC 2.4.2.30) was carried out by using either increasing concentrations of beta-NAD+ (donor substrate) at a fixed protein concentration or increasing concentrations of PARP (acceptor substrate) at a fixed beta-NAD+ concentration. The [32P]ADP-ribose polymers synthesized were chemically detached from PARP by alkaline hydrolysis of the monoester bond between the carboxylate moiety of Glu and the polymer. Nucleic acid-like polymers were then analyzed by high-resolution polyacrylamide gel electrophoresis and autoradiography. The ADP-ribose chain lengths observed displayed substrate concentration-dependent elongation from 0.2 microM to 2 mM beta-NAD+. Similar results were observed at fixed concentrations of 4.5, 9, 18, 27, and 36 nM PARP. Therefore, we conclude that the concentration of the ADP-ribose donor substrate determines the average chain length of the polymer synthesized. In contrast, the polymer size was unaltered when the concentration of PARP was varied from 4.5 to 18 nM at a fixed beta-NAD+ concentration. However, when PARP concentrations > 18 nM were used, the total amount of monomeric ADP-ribose produced was noticeably less. Therefore, we conclude that high concentrations of PARP lead to acceptor substrate inhibition at the level of the ADP-ribose chain initiation reaction.