cssi/SciSciGPT-SciSciNet huggingface dataset:
Early failure after non-resectional mitral valve repair with artificial chordae.

Severe recurrent mitral regurgitation within 1 year of mitral valve repair is usually attributed to a technical issue with the original repair procedure. However, when artificial chordae are employed to correct mitral valve prolapse, ventricular remodeling (ie, decreased ventricular size) can lead to recurrent prolapse and valve dysfunction. To illustrate this phenomenon, we present two patients who experienced early failure after undergoing mitral valve repair with artificial chordae.
Newborn With Severely Depressed Left Ventricular Function: Acute Myocardial Infarction in a Newborn

Abstract We describe a rare case of spontaneous coronary artery thrombosis in a newborn leading to rapid severe ventricular dysfunction. Early diagnosis is critical and management strategies are va...
Comparison of Knowledge and Information-Seeking Behavior After General COVID-19 Public Health Messages and Messages Tailored for Black and Latinx Communities : A Randomized Controlled Trial.

BACKGROUND: The paucity of public health messages that directly address communities of color might contribute to racial and ethnic disparities in knowledge and behavior related to coronavirus disease 2019 (COVID-19). OBJECTIVE: To determine whether physician-delivered prevention messages affect knowledge and information-seeking behavior of Black and Latinx individuals and whether this differs according to the race/ethnicity of the physician and tailored content. DESIGN: Randomized controlled trial. (Registration: ClinicalTrials.gov, NCT04371419; American Economic Association RCT Registry, AEARCTR-0005789). SETTING: United States, 13 May 2020 to 26 May 2020. PARTICIPANTS: 14 267 self-identified Black or Latinx adults recruited via Lucid survey platform. INTERVENTION: Participants viewed 3 video messages regarding COVID-19 that varied by physician race/ethnicity, acknowledgment of racism/inequality, and community perceptions of mask wearing. MEASUREMENTS: Knowledge gaps (number of errors on 7 facts on COVID-19 symptoms and prevention) and information-seeking behavior (number of web links demanded out of 10 proposed). RESULTS: 7174 Black (61.3%) and 4520 Latinx (38.7%) participants were included in the analysis. The intervention reduced the knowledge gap incidence from 0.085 to 0.065 (incidence rate ratio [IRR], 0.737 [95% CI, 0.600 to 0.874]) but did not significantly change information-seeking incidence. For Black participants, messages from race/ethnicity-concordant physicians increased information-seeking incidence from 0.329 (for discordant physicians) to 0.357 (IRR, 1.085 [CI, 1.026 to 1.145]). LIMITATIONS: Participants' behavior was not directly observed, outcomes were measured immediately postintervention in May 2020, and online recruitment may not be representative. CONCLUSION: Physician-delivered messages increased knowledge of COVID-19 symptoms and prevention methods for Black and Latinx respondents. The desire for additional information increased with race-concordant messages for Black but not Latinx respondents. Other tailoring of the content did not make a significant difference. PRIMARY FUNDING SOURCE: National Science Foundation; Massachusetts General Hospital; and National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases.
Predicting Adverse Histopathology and Need for Postsurgical Adjuvant Therapy for Human Papilloma Virus–Associated Oropharynx Carcinoma

ObjectiveFor human papillomavirus–associated oropharynx carcinoma treated with definitive surgery, we aimed to find predictors of adverse histopathology indicating the possible need for adjuvant th...
Sildenafil Induced Headache and Blurry vision (5391)

Objective: We report a case of worsening headaches and occult vision loss in a patient with pulmonary hypertension. Background: A wide range of conditions can present with headaches and blurred vision. Migraine and increased intracranial pressure are among the most common causes. However, when visual symptoms are atypical for a headache syndrome, other etiologies should be considered. Design/Methods: Case report Results: A 47-year-old female with pulmonary hypertension presented with headaches and vision changes progressing over 1 year. She had difficulty focusing because her vision was a “total blur” with black dots all over the visual fields. She had no double vision, sudden onset vision loss, pain with eye movement, or transient visual obscuration. Medications included sildenafil and visual changes worsened with increased sildenafil dose. On exam, her best-corrected visual acuity decreased to 20/30 in each eye. The pupil exam was normal without relative afferent pupillary defect. The ocular motility was normal and there was no misalignment. Her fundus exam was normal with healthy optic nerves and maculae in each eye. Goldmann visual field showed full field in the right eye and generalized mild constriction in the left eye. MRI brain was normal. Full field electroretinography (ERG) showed normal amplitude, wave form, and timing. Multi-focal ERG showed blunting of the foveal peaks in both eyes, with focal depression in the macula, more prominent in the left eye. A diagnosis of presumed sildenafil associated maculopathy coincidental with primary headache syndrome was made. After discussion with her pulmonologist, sildenafil was discontinued. At 2 months follow-up, her headaches improved, and visual symptoms were stable. Conclusions: Vision changes can be separate from a headache syndrome. In our patient, sildenafil was associated with progressive vision loss due to maculopathy, which was unrelated to worsened primary headaches. In patient with pulmonary hypertension, the decision to discontinue sildenafil should be made with Pulmonology. Disclosure: Dr. Liu has nothing to disclose. Dr. Davila has nothing to disclose. Dr. Moss has nothing to disclose.
Survival and Recruitment among Non-Migratory Canada Geese (Branta canadensis): Influence of Gosling Sex, Hatching Date, Mass at Fledging, and Family Type

Among some Arctic-nesting geese, mass at fledging impacts first-year survival and recruitment into the breeding population, but this might not be true for temperate-nesting geese. For 25 years, we examined what variables impacted survival and recruitment of 731 Canada Geese (Branta canadensis) fledglings raised in Connecticut, USA by tracking individually marked birds throughout their lives. At fledging, the number of females (391) were similar to males (340), but by the end of the first year of life, females (247) outnumbered males (187). This can be explained due to the apparent survival rates for juvenile females (0.63) being higher than for males (0.55). Dispersal rate from natal areas were similar for males and females during the first year of life and cannot account for why females outnumbered males after one year of life. Apparent survival rates of female fledglings to the end of the second year was 0.48. For the 247 females still alive at the end of their first year of life, 190 were still alive at the end of their second year of life, yielding a 0.77 apparent survival rates during their second year of life. Sex was the only variable that explained the survival of fledglings until the end of their first year of life. The probability of females surviving the second year of life was not influenced by hatching date, fledging age, fledging mass, or family type. Heavier females at fledging were more likely to be recruited into the breeding population than lighter ones. Our results indicate that while an inability to acquire sufficient mass as a gosling does not affect survival, it impacts the ability to be recruited.
How to Develop a Training Manual/Protocol

ABSTRACT.The training of new technicians is often the responsibility of middle management or staff coordinator in the laboratory. Training in a large laboratory that does several types of neurodiagnostic testing or monitoring can fall on several coordinators. In this situation, it can be difficult to track what training can be done and what has already been completed.The purpose of this article is to assist technologists creating a training manual. Each laboratory has specific criteria to meet, with testing as well as with professional levels of new employees. Information and protocols a new employee needs to learn are documented and placed in a logical order. That compiled information can then be reused for each new employee. The training manual thus developed becomes a training tool, saving the technologist coordinator both time and repeated effort, while encouraging uniformity in orientation among new employees.For larger laboratories offering several areas of testing and monitoring, it is important to...
TH-B-213-00: Spine SBRT

Spine SBRT is a common option for spine radiation therapy. This session will describe the clinical implementation of a spine SBRT program using linear accelerators, Cyberknife, and gimbaled devices. Treatment planning, QA, treatment delivery, patient immobilization and setup, and commissioning will be discussed. The goals of spine SBRT clinical workflow are common to all treatment devices but clinical practices depend upon the treatment device and differences will be detailed. Tolerances of patient setup, immobilization and imaging are defined by the close proximity of the spinal cord to the target and tolerances will be discussed along with error minimization practices. Published studies regarding the clinical rationale and implementation of spine SBRT will be reviewed. Learning Objectives: 1. 1.Understand the clinical rationale for spine SBRT. 2. 2.Understand the similarities and differences of difference treatment devices utilized for spine SBRT. 3. 3.Understand the clinical physics methods for commissioning a spine SBRT program. 4. 4.Understand the clinical workflow of a spine SBRT program including treatment planning techniques and quality assurance measurements. Travel Expenses and Research Funding from Elekta
Analysis of Transport Phenomena Using Scaling and Physical Models

Publisher Summary This chapter discusses some simple approaches that can be employed to obtain information on the rate of heat and mass transfer for both laminar and turbulent motion. One approach is based on dimensional scaling and hence ignores the transport equations. Another approach, while based on the transport equations, does not solve them in the conventional way. Instead, it replaces them by some algebraic expressions, which are obtained by what could be called physical scaling. Conventional dimensional analysis uses single length and time scales to obtain dimensionless groups. The chapter describes a new kind of dimensional analysis, which employs two kinds of such scales, the microscopic scale and the macroscopic scale. Turbulent transport is represented as a succession of simple laminar flows. For a liquid–fluid interface, a roll cell model is employed for turbulent motion as well as for interfacial turbulence. The chapter describes various physical and scaling models that demonstrate transport phenomena, especially heat and mass transfer.
Neurotransmitter Receptor Sites in the Spinal Cord

Since the studies discussed in this chapter concern the distribution of receptors for neurotransmitters, it is important to specify that the term “receptor” implies a physiologically functional unit. Binding of a transmitter molecule to its binding site on the neuronal membrane surface initiates a physical change in the receptor unit that results in a physiological change, i.e., a change in membrane ion permeability (nicotinic cholinergic receptor) or activation of an enzyme resulting in a change in the level of a biochemical intermediate within the cell (β-adrenergic receptors and many peptide hormone receptors). Binding studies and autoradiograms, however, reflect just the binding site portion of the receptor unit, and such data must be described in terms of binding sites. However, the radiolabeled ligands used to prepare the autoradiograms are pharmacologically active compounds whose physiological effects on the system may be well characterized. Therefore, in this discussion of the biological significance of binding sites, I refer to them as receptors.
inferences about the mean of a single population

This chapter describes inferences about the mean of a single population. The chapter states the general considerations for hypothesis testing. The null hypothesis (denoted by the symbol H 0 ) and the alternative hypothesis (denoted by H 1 ) are stated. It is important to understand that it cannot be proved whether H 0 or H 1 is true because the entire population cannot be measured. It is assumed that H 0 is true. Then the data is obtained and the assumption is tested out. If this assumption is unlikely to be true, it is abandoned and the “bets should be switched” to H 1 , otherwise the assumption is retained. Before collecting any data, it is necessary to define in numerical terms what is meant by “unlikely to be true.” In statistical terminology, this is called selecting a criterion (or level) of significance, represented by the symbol a. Having selected a criterion of significance, data is selected and the appropriate statistical test is computed.
An Erlang-based stochastic model for patient flow

In this paper, an Erlang-based stochastic model for patient flow is presented. The model is proposed as an effective tool to obtain analytic results for the stochastic process of patient flow in a health care environment. Through the use of two previously published examples, it is shown that the stochastic model can be developed quickly, is not computationally intensive and provides a good representation of the empirical patient flow.
Factors encouraging the growth of sustainable communities : A Jamaican case study

The concept of sustainable communities assumes a process of social and/or economic development that has as a high priority, the needs of the future generation. However, models of social and economic development employed in developing countries, must rely heavily on political, social and psychological empowerment techniques being employed at the community level, in order to warrant any type of sustainability becoming apparent. A case study taken from Kingston, Jamaica recounts and examines the experience of a Social Work Unit/private company in partnership, becoming involved in a low-income community's drive for sustainable development. The paper will reflect on the intervention, the analysis of which suggests inclusion and acceptance of a 'third party' support mechanism by the community and the presence of visible political and economic support from the government as the two factors which impact directly on creation of sustainable development initiatives in communities such as this
Magnetic Resonance Image Segmentation by Contextual Fuzzy Clustering

This article presents a fuzzy c-mean clustering algorithm, named contextual thresholded fuzzy c-mean, for the segmentation of magnetic resonance brain images. This algorithm incorporates contextual information into the thresholded fuzzy c-mean algorithm. This is done by adjusting the membership of voxels adaptively based upon the membership context of the surrounding voxels. The performance of this algorithm was compared both to crisp and to fuzzy clustering algorithms using “phantom” data and a set of clinical examples. The contextual fuzzy c-mean algorithm gave the best results of those tested when the criteria were accuracy of volume measurements and homogeneity of brain tissue types. A graphical user interface was developed for these methods to provide an easy-to-use software tool for clinical environments.
Primate Shadow Play

Comparing the genome sequences of distantly related species can yield valuable information about the locations of genes and of the control elements that regulate them. In their Perspective, [Gibbs and Nelson][1] discuss a new technique called phylogenetic shadowing which enabled comparison of the genome sequences of 17 closely related primate species and Homo sapiens ([ Boffelli et al .][2]). This method revealed the location of exons and regulatory regions in the human genome with increased precision. [1]: http://www.sciencemag.org/cgi/content/full/299/5611/1331 [2]: http://www.sciencemag.org/cgi/content/short/299/5611/1391
Automatic Detection of Beaked Whales from Acoustic Seagliders

Abstract : The U.S. Navy s use of tactical mid-frequency active sonar has been linked to marine mammal strandings and fatalities (NMFS 2001). These events have generated legal challenges to the Navy s peacetime use of mid-frequency sonar, and have limited the Navy s at-sea anti-submarine warfare training time. Beaked whales may be particularly sensitive to mid-frequency sonar. A mobile, persistent surveillance system that could detect, classify and localize beaked whales will help resolve the conflict between the Navy s need for realistic training of mid-frequency sonar operators and the Navy s desire to protect marine mammal populations worldwide. Underwater gliders equipped with appropriate acoustic sensors, processing, and detection systems passive acoustic monitoring (PAM) gliders may offer a partial solution to the problem. The acoustically-equipped Seaglide(trademark) from the Applied Physics Laboratory of the University of Washington (APL-UW) is one such platform. A Seaglider can travel about 20 km/day through the water for a period of weeks to months, dive from the surface to 1000 m and back in a few hours, and use two-way satellite (Iridium) telemetry for data and command transfer. This makes it potentially highly useful for the long-term goal of this project, mitigating impacts of Navy operations on marine mammals. The objective of this effort is to develop techniques for detection and classification of odontocetes echolocation clicks and especially beaked whale sounds for the PAM Seaglider. Because any methods developed must run in the operational environment of the Seaglider, they must have a low average computational cost because of the limited processing power and battery life of the Seaglider. The performance of the detection and classification system will be evaluated on several field trials.
Tract- and county-level income inequality and individual risk of obesity in the United States

Abstract Objectives We tested three alternative hypotheses regarding the relationship between income inequality and individual risk of obesity at two geographical scales: U.S. Census tract and county. Methods Income inequality was measured by Gini coefficients, created from the 2000 U.S. Census. Obesity was clinically measured in the 2003–2008 National Health and Nutrition Examination Survey (NHANES). The individual measures and area measures were geo-linked to estimate three sets of multi-level models: tract only, county only, and tract and county simultaneously. Gender was tested as a moderator. Results At both the tract and county levels, higher income inequality was associated with lower individual risk of obesity. The size of the coefficient was larger for county-level Gini than for tract-level Gini; and controlling income inequality at one level did not reduce the impact of income inequality at the other level. Gender was not a significant moderator for the obesity-income inequality association. Conclusions Higher tract and county income inequality was associated with lower individual risk of obesity, indicating that at least at the tract and county levels and in the context of cross-sectional data, the public health goal of reducing the rate of obesity is in line with anti-poverty policies of addressing poverty through mixed-income development where neighborhood income inequality is likely higher than homogeneous neighborhoods.
ASAP: interactive quantification of 2D airway geometry

Evaluation of most normal and patho-pulmonary physiology has relied upon indirect measures of pulmonary function which yield global estimates of underlying structural and functional deficits, which are usually very heterogeneous in nature. Early signs of disease are not recognizable by these techniques, nor are they usually recognizable by the manifestation of physical symptoms. As X-ray CT technology has improved, imaging has held a promise to provide the detailed information here-to-fore missing in standard pulmonary function evaluations. A full solution to the imaging and analysis problem requires true dynamic volumetric approaches to facilitate tracking the lung through space during respiratory maneuvers, and following the radiopacified blood and airflow tracers as they pass through the pulmonary vascular bed or wash in or out of the alveolar air spaces. However, high- resolution, high-speed, stacked single-slice approaches for lung imaging have brought the state-of-the-art to a point where quantitative airway evaluation can play an important role in the study of lung disease and normal lung physiology, if one limits the evaluation to those airway segmented sliced in true cross-sections, or to the evaluation of those airway segments for which a true cross-sectional image can be reformatted from the original stacked sections. This paper presents a software system, called ASAP (for Airway Segmentation and Analysis Program), which provides a rapid, minimally-interactive method for objective identification of airway borders and the reporting of associated geometric measures of diameters and wall thicknesses. We demonstrate that this system yields highly reproducible results both within and between observers, and quantitative measures are accurate to within the resolution of the scanner when phantoms of known geometry are evaluated. Results included here demonstrate that the well-accepted half-max criteria for border definition is a rough approximation, which when applied to structures such as intrathoracic airways yields incorrect results. Our analysis shows that the inner and outer wall detection thresholds must be customized based upon the size of the structure of interest.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Health Practice in Long-Term Survivors of Hodgkin's Lymphoma

Purpose To compare the health practice of Hodgkin's lymphoma (HL) survivors and their siblings, and to assess the impact of socioeconomic status and disease history on health practice of HL survivors. Methods and Materials We conducted a questionnaire study on long-term HL survivors and their siblings on health care utilization, health habits, and screening behavior. Results A total of 511 HL survivors (response rate of 50%, including survivors lost to contact) and 224 siblings (response rate, 58%) participated. Median time from HL diagnosis was 15 years. Significantly more survivors than siblings had a physical examination in the past year (63% vs. 49%, p = 0.0001). Male survivors were significantly more likely than siblings to perform monthly self-testicular examinations (19% vs. 9%, p = 0.02). Among survivors, higher household income ( p = 0.01) independently predicted for having had a physical examination in the past year. Lower educational level ( p = 0.0004) and history of relapsed HL ( p = 0.03) were independent predictors for smoking, moderate/heavy alcohol use, and/or physical inactivity. Conclusions Compared with siblings, long-term HL survivors have a higher level of health care utilization and better screening practice. Survivors from lower socioeconomic background had lower adherence to routine health care and greater report of unhealthy habits. Survivors with history of relapsed HL were also more likely to engage in unhealthy habits.
Imaging of the postoperative spine

With the widespread prevalence of back pain, and approximately 200,000 lumbar spine operations annually in the United States, imaging of the postoperative lumbar spine has become a major diagnostic issue. The many causes of the failed back surgery syndrome make the diagnosis of the etiology of the patient's symptom complex very important to the treating physician. With the varied types of surgery, the increasing use of fusion hardware, and the myriad of complicating factors, the imaging strategy must be flexible enough to be comprehensive in the evaluation of these difficult patients. This article will address the normal and abnormal findings after lumbar spine surgery.
Term Limitation in a Dynamic Model of Partisan Balance

In November 1992, voters in fourteen states considered ballot propositions to adopt term limits for members of Congress. All fourteen propositions passed (ten received more than 60% support), bringing the total number of states with congressional term limits to fifteen. Much of the discussion of term limitation has focused on issues of representation, the strength of parties, and the functioning of Congress after the adoption of limits (Benjamin and Malbin, 1992), (Will, 1992). This paper explores an important but less discussed consequence of term limitation, its impact on the partisan balance of legislatures. We inquire how electoral dynamics, incumbent advantage, and voluntary retirement interact with a term limit to produce a new balance between parties in a two-party legislature. Which party is favored by the introduction of term limits? How does the length of the term limit matter? Are there conditions such that one party will be favored by any limit, regardless of how restrictive?
Vmoms — A computer code for finding moment solutions to the grad-shafranov equation

Abstract Title of program: VMOMS Catalogue number: ABSH Program obtainable from: CPC Program Library, Queen's University of Belfast, N. Ireland (See application form in this issue) Computer: PDP-10/KL10; Installation: ORNL Fusion Energy Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830, USA Operating system: TOPS 10 Programming language used: FORTRAN High speed storage required: 9000 words No. of bits in a word: 36 Overlay structure: none Peripherals used: line printer, disk drive No. of cards in combined program and test deck: 2839 Card punching code: ASCII
An automated modelling and reformulation system for design optimization

Abstract Many optimization problems in engineering rely on the use of computer algorithms for solving nonlinear programming (NLP), mixed-integer linear programming (MILP) and mixed-integer nonlinear programming (MINLP) models. Although a number of powerful optimization packages are currently available, it is still far from trivial for design engineers to properly formulate optimization models. Since a qualitative knowledge base does exist for expert modelling of optimization problems, there is an incentive to develop computer systems that can encode this knowledge. In this work we develop some of this qualitative knowledge and describe a knowledge-based implementation for automatic model reformulation. The resulting program, REFORM, symbolically reformulates nonlinear and mixed-integer models to increase the robustness and efficiency of the respective algorithms. Models specified in GAMS input files are automatically preprocessed by REFORM to generate a new, well-formulated model. Moreover, its capabilities include constraint reformulation to induce linearity and convexity, tightening of bounds, problem scaling and fixing binary (0–1) variables a priori. While some of these represent common knowledge in the area of optimization, the tight bounding procedure is a novel method that exploits monotonicity in the linear and nonlinear equations, and has applications for fixing binary variables. Computational results are presented to illustrate how the implementation of qualitative knowledge-based problem reformulation can improve the solution of poorly developed models.
Social context of HIV risk behaviours among male-to-female transgenders of colour.

To explore the social context of drug use and sexual behaviours that put male-to-female (MTF) transgenders at risk for HIV, focus groups were conducted consisting of African American, Latina and Asian and Pacific Islander MTF transgenders (N=48) who reside or work in San Francisco, California. Participants were likely to report having unprotected sex with primary partners to signify love and emotional connection, as well as to receive gender validation from their partners. In contrast, viewing sex work with customers as a business encouraged intentious to use condoms. Safer sex intentions with customers were frequently undermined by urgent financial needs, which stemmed from transphobia, employment discrimination and costly procedures associated with gender transition. Participants reported using drugs as a way to cope with or escape life stresses associated with relationships, sex work, transphobia and financial hardship. Interventions with at-risk MTF transgenders should address the interpersonal and so...
Implementing a pilot leadership course for internal medicine residents: design considerations, participant impressions, and lessons learned

Effective clinical leadership is associated with better patient care. We implemented and evaluated a pilot clinical leadership course for second year internal medicine residents at a large United States Academic Medical Center that is part of a multi-hospital health system. The course met weekly for two to three hours during July, 2013. Sessions included large group discussions and small group reflection meetings. Topics included leadership styles, emotional intelligence, and leading clinical teams. Course materials were designed internally and featured “business school style” case studies about everyday clinical medicine which explore how leadership skills impact care delivery. Participants evaluated the course’s impact and quality using a post-course survey. Questions were structured in five point likert scale and free text format. Likert scale responses were converted to a 1-5 scale (1 = strongly disagree; 3 = neither agree nor disagree; 5 = strongly agree), and means were compared to the value 3 using one-way T-tests. Responses to free text questions were analyzed using the constant comparative method. All sixteen pilot course participants completed the survey. Participants overwhelmingly agreed that the course provided content and skills relevant to their clinical responsibilities and leadership roles. Most participants also acknowledged that taking the course improved their understanding of their strengths and weaknesses as leaders, different leadership styles, and how to manage interpersonal conflict on clinical teams. 88% also reported that the course increased their interest in pursuing additional leadership training. A clinical leadership course for internal medicine residents designed by colleagues, and utilizing case studies about clinical medicine, resulted in significant self-reported improvements in clinical leadership competencies.
Reconciling particulate organic carbon flux and sediment community oxygen consumption in the deep North Pacific

THE mineralization of organic carbon in the deep ocean has been considered an enigma in the North Pacific. Comparisons of the supply of particulate organic carbon (POC) with estimates of its mineralization to CO2 by the sediment community have indicated that the supply of POC sinking into the benthic boundary layer may be as much as 97% short of meeting the organic carbon demand of the sediment community1,2. These previous findings were based on short-time-series measurements (<14 days) conducted in situ with sediment traps and benthic respirometers. We report here a comparison of long-time-series measurements (2.3 years) of POC flux into the benthic boundary layer and concurrent, seasonal measurements of sediment community oxygen consump-tion. We chose a single abyssal station (4,100 m depth) in a region of the eastern North Pacific where there is a strong seasonal fluctuation in primary production, and where previous studies1,2 showed the supply of POC to be as much as an order of magnitude lower than the demand by the sediment community. Our measure-ments, using the same methods, show agreement to within 15% between organic carbon supply and demand. This reconciliation is attributable to the inclusion of previously undetected episodic inputs of POC into the benthic boundary layer. These episodic inputs are critical to sustaining the sediment community at this station, and are probably important in other deep-sea environments where seasonal fluctuations in primary production are prominent in surface waters.
Microwave and infrared spectra of C2H4...HCCH : barrier to twofold internal rotation of C2H4

Abstract Microwave spectra of C 2 H 4 …HCCH, C 2 H 4 …DCCH, C 2 H 4 …DCCD, D 2 CCH 2 …HCCH, and trans-HDCCHD…HCCH have been recorded using a pulsed-nozzle Fourier-transform microwave spectrometer. An α-type, Δ K α = 0 spectrum is observed, with a number of transitions being split into doublets due to tunneling arising from the hindered internal rotation of the ethylene and about its CC bond. For the normal species we find A = 25981 (33) MHz, B + C 3478.2560(13) MHz, and B  C = 89.45(18) MHz. The complex is shown to have a C 2v structure in which the HCCH unit hydrogen bonds to the ethylene π cloud, with the HCCH axis normal to the plane of the ethylene. The hydrogen bond length is found to be 2.78 A. Centrifugal-distortion analysis yields a weak-bond stretching force constant of 2.5 N/m (0.025 mdyn/A), corresponding to a stretching frequency of 56 cm −1 . Stark effect measurements determine the electric dipole moment of the complex to be 8.852 (21) × 10 −31 C m (0.2654(6) D). The observed tunneling-induced splittings yield an internal rotation barrier of 240 cm −1 . An infrared spectrum of the asymmetric acetylenic CH stretch in the complex has also been measured using an optothermal color-center laser spectrometer. The rotational lines are predissociation broadened, preventing the resolution of K structure. The observed band origin, ν 0 = 3271.61 cm −1 , is nearly identical to that found for the similar vibration in the acetylene dimer.
Role of thyroid hormone and insulin in control of cardiac isomyosin expression.

Previous studies show that both diabetes and thyroid state exert a strong regulatory influence on the pattern of rodent cardiac isomyosin expression. Therefore, we determined the separate and combined effects of thyroid hormone (T3) and insulin treatment on rodent cardiac myosin heavy chain (MHC) expression using a model of combined thyroid deficiency (Tx) and diabetes (D). The combination of Tx and D completely transformed cardiac isomyosin expression such that the fast alpha-myosin heavy chain (MHC) was completely repressed at both the protein and mRNA level of expression; whereas, the slow beta-MHC was upregulated to constitute 100% of the total MHC pool, based on both protein and mRNA analyses. Daily low doses of exogenous T3 treatment (3 micrograms/kg b.w. i.p.). in the absence of insulin treatment, partially restored expression of the alpha-MHC, while inhibiting expression of the beta-isoform. In contrast daily insulin treatment (4 U/rat), in the absence of exogenous T3 treatment, failed to exert any significant influence on the pattern of isomyosin expression in the thyroid-deficient diabetic rat model. Furthermore, when exogenous T3 was administered in conjunction with insulin, the effect on MHC mRNA expression was greater than that of T3 alone, thus suggesting the existence of interaction between T3 and insulin action in the regulation of MHC mRNA expression. Collectively, these findings suggest that: (a) thyroid state is a dominant regulator of cardiac isomyosin phenotype: and (b) insulin does not exert any regulatory influence on cardiac MHC expression in a severe thyroid deficient state, instead it requires a critical level of circulating T3 in order to be effective in blunting MHC transformation associated with diabetes. It is thus concluded that the regulation of cardiac MHC by insulin is a complex mechanism involving interaction of insulin with subcellular factors likely to have impact on the specific action of T3. This interaction is disrupted in the absence of sufficient thyroid hormone.
P-M hybrid dysgenesis does not mobilize other transposable element families in D. melanogaster

Mobilization of the P family of transposable elements in Drosophila melanogaster occurs in the hybrid progeny of males from an element-bearing strain (P strain) and females from an element-free strain (M strain)1. We tested whether the same crosses could mobilize other families of transposable elements. A mating scheme was used in which a set of X chromosomes was kept for 20 generations in either the active condition (known as hybrid dysgenesis) or the inactive condition (nondysgenic). Examination of 19 families of transposable elements by in situ hybridization indicated that only the P family was measurably mobilized under dysgenic conditions. Thus, P–M hybrid dysgenesis does not increase the transpositional activity of other families of transpos-able elements in D. melanogaster. We discuss possible explanations for several published reports to the contrary2–5.
Hydrographic conditions in the Eastern Pacific before, during and after the 1982/83 El Niño

Abstract Between June 1981 and June 1984 a total of thirteen CTD sections were made across the equator along 85°W. On some of these cruises additional sections were made along 5°S and 10°30'S between 85°W and the South American coast. This sampling period covers the events that took place during the 1982/83 El Nino. These sections are used to describe the variability that took place before, during and after this major event. At the surface little evidence was found for a major southward flooding of warm, low salinity water from north of the equator that has been observed during some previous El Ninos. Major changes took place in the sub-surface hydrographic structures. The thermostad between 13°C and 16°C, which is a prominent feature of the hydrography in this region, disappeared early in 1983 and reappeared early in 1984. The vertical temperature gradient along the equator and along the coast, which is usually quite variable with depth, became much more uniform in early 1983; it regained its normal structure by early 1984. Changes were not confined to the upper ocean but were evident over the whole depth interval sampled (1000m). During November 1982 evidence was found for symmetric poleward spreading of the equatorial disturbance along the eastern boundary. Many of the changes that took place are consistent with linear models based on equatorial wave theory. These observations presented a unique opportunity for observing the ocean response to a major interannual change in the wind forcing.
Architecture of the Tn7 Posttransposition Complex: An Elaborate Nucleoprotein Structure

Four transposition proteins encoded by the bacterial transposon Tn7, TnsA, TnsB, TnsC, and TnsD, mediate its site- and orientation-specific insertion into the chromosomal site attTn7. To establish which Tns proteins are actually present in the transpososome that executes DNA breakage and joining, we have determined the proteins present in the nucleoprotein product of transposition, the posttransposition complex (PTC), using fluorescently labeled Tns proteins. All four required Tns proteins are present in the PTC in which we also find that the Tn7 ends are paired by protein-protein contacts between Tns proteins bound to the ends. Quantification of the relative amounts of the fluorescent Tns proteins in the PTC indicates that oligomers of TnsA, TnsB, and TnsC mediate Tn7 transposition. High-resolution DNA footprinting of the DNA product of transposition attTn7Colon, two colonsTn7 revealed that about 350 bp of DNA on the transposon ends and on attTn7 contact the Tns proteins. All seven binding sites for TnsB, the component of the transposase that specifically binds the ends and mediates 3' end breakage and joining, are occupied in the PTC. However, the protection pattern of the sites closest to the Tn7 ends in the PTC are different from that observed with TnsB alone, likely reflecting the pairing of the ends and their interaction with the target nucleoprotein complex necessary for activation of the breakage and joining steps. We also observe extensive protection of the attTn7 sequences in the PTC and that alternative DNA structures in substrate attTn7 that are imposed by TnsD are maintained in the PTC.
Caenorhabditis elegans Glutamate Transporters Influence Synaptic Function and Behavior at Sites Distant from the Synapse

To ensure precise neurotransmission and prevent neurotoxic accumulation, l-glutamate (Glu), the major excitatory neurotransmitter in the brain, is cleared from the synapse by glutamate transporters (GluTs). The molecular components of Glu synapses are highly conserved between Caenorhabditis elegans and mammals, yet the absence of synaptic insulation in C. elegans raises fundamental questions about Glu clearance strategies in the nematode nervous system. To gain insight into how Glu clearance is accomplished and how GluTs impact neurotransmission, we probed expression and function of all 6 GluTs found in the C. elegans genome. Disruption of each GluT impacts multiple Glu-dependent behaviors, with GluT combinations commonly increasing the severity of behavioral deficits. Interestingly, the sole GluT that we find expressed in neurons is localized predominantly in presynaptic neurons, in contrast to the postsynaptic concentration of neuronal GluTs typical in mammals. Moreover, 3 of the 6 GluT genes appear strongly expressed on the capillary excretory canal cell, where they affect Glu-dependent behaviors from positions distal to glutamatergic circuits. Indeed, our focused study of GLT-3, one of the distally expressed GluTs, shows that despite this distance, GLT-3 function can balance the activity mediated by synaptic release and synaptic receptors. The effects of distal GluTs on glutamatergic circuits support that Glu diffusion outside the vicinity of the synapse is a critical factor in C. elegans neurotransmission. Together with the presynaptic localization of neuronal GluTs, these observations suggest an unusual strategy for Glu clearance in C. elegans.
Classification of degraded cartilage through multiparametric MRI analysis.

Abstract MRI analysis of cartilage matrix may play an important role in early detection and development of therapeutic protocols for degenerative joint disease. Correlations between MRI parameters and matrix integrity have been established in many studies, but the substantial overlap in values observed for normal and for degraded cartilage greatly limits the specificity of these analyses. We implemented established multiparametric analysis methods to define data clusters corresponding to control and degraded bovine nasal cartilage in two-, three-, and four-dimensional parameter spaces, and applied these results to discriminant analysis of a validation data set. Analyses were performed using the parameters ( T 1 , T 2 , k m , ADC), where k m is the magnetization transfer rate and ADC is the apparent diffusion coefficient. Results were compared to univariate analyses. Multiparametric k -means clustering led to no improvement over univariate analyses, with a maximum sensitivity and specificity in the range of 60–70% for the detection of degradation using T 1 , and in the range of 80% sensitivity but only 36% specificity using the parameter pair ( T 1 , k m ). In contrast, model-based analysis using more general Gaussian clusters resulted in markedly improved classification, with sensitivity and specificity reaching levels of 80–90% using the pair ( T 1 , k m ). Finally, a fuzzy clustering technique was implemented which may be still more appropriate to the continuum of degradation seen in degenerative cartilage disease. In view of its success in identifying mild cartilage degradation, the formal multiparametric approach implemented here may be applicable to the nondestructive evaluation of other biomaterials using MRI.
Challenges Faced by Women with Disabilities Under TANF

SUMMARY A number of studies report the multiple problems facing women during the welfare reform transition. Within this group is a large number of single mothers struggling with both poverty and chronic health problems or disabilities. Those with these additional challenges might be expected to experience less success in moving out of poverty than those without these health challenges. In this study, we examine the progress of 178 women around the state of Wisconsin who were interviewed repeatedly about their experiences with welfare reform and poverty between 1997 and 2000, when the Wisconsin Works (W-2) program was being implemented. The incidence of health problems is related to level of education, and the type of disability has major impacts on expected outcome. Those with less education are more likely to suffer from health problems, especially mental health issues, depression and post-traumatic stress, which seem to be the most debilitating. These women also had difficulty accessing non-work support...
Anterior cingulate proton spectroscopy glutamate levels differ as a function of smoking cessation outcome.

Background Cigarette smoking is the leading preventable cause of death. Unfortunately, the majority of smokers who attempt to quit smoking relapse within weeks. Abnormal dorsal anterior cingulate cortex (dACC) function may contribute to tobacco smoking relapse vulnerability. Growing evidence suggests that glutamate neurotransmission is involved in mediating nicotine dependence. We hypothesized that prior to a cessation attempt, dACC glutamate levels would be lower in relapse vulnerable smokers.
Incremental CH4 and N2O mitigation benefits consistent with the US Government's SC-CO2 estimates

Benefit–cost analysis can serve as an informative input into the policy-making process, but only to the degree it characterizes the major impacts of the regulation under consideration. Recently, the US, amongst other nations, has begun to use estimates of the social cost of CO2 (SC-CO2) to develop analyses that more fully capture the climate change impacts of GHG abatement. The SC-CO2 represents the aggregate willingness to pay to avoid the damages associated with an additional tonne of CO2 emissions. In comparison, the social costs of non-CO2 GHGs have received little attention from researchers and policy analysts, despite their non-negligible climate impact. This article addresses this issue by developing a set of social cost estimates for two highly prevalent non-CO2 GHGs, methane and nitrous oxide. By extending existing integrated assessment models, it is possible to develop a set of social cost estimates for these gases that are consistent with the SC-CO2 estimates currently in use by the US federal ...
Traditional production, communal land tenure, and policies for environmental preservation in the South Pacific

Abstract Instead of maximizing the expected monetary return of land usage, Pacific islanders manage land so that it renders an optimal mix of cash income and non-monetary cultural goods. Evidence from cropping patterns in Fiji suggests that the production of these cultural goods is linked to traditional agriculture which produces less ecological deterioration than its commercial counterpart. The capacity for village land to support traditional activities is highest under a regime of communal land tenure where decision making is centralized. A regime of private land tenure lowers this capacity because decentralized decision making raises the coordination costs of preserving special areas of land for traditional purposes. This means that if development planners rush to replace traditional regimes of communal land tenure with `modern' systems of private land ownership, they might also observe a correlated increase in land degradation, even if new codes of private property are perfectly enforceable. A two-sector growth model can be used to show that the welfare-neutral `bribe' required from the government to increase the amount of village land preserved in the steady state is lower under a regime of communal land tenure. One counterintuitive result is that a high subjective discount rate does not always imply a high level of environmental degradation. Observations from the South Pacific have application for environmental policy in other developing countries.