cssi/SciSciGPT-SciSciNet huggingface dataset:
Applications of node-based resilience graph theoretic framework to clustering autism spectrum disorders phenotypes

With the growing ubiquity of data in network form, clustering in the context of a network, represented as a graph, has become increasingly important. Clustering is a very useful data exploratory machine learning tool that allows us to make better sense of heterogeneous data by grouping data with similar attributes based on some criteria. This paper investigates the application of a novel graph theoretic clustering method, Node-Based Resilience clustering (NBR-Clust), to address the heterogeneity of Autism Spectrum Disorder (ASD) and identify meaningful subgroups. The hypothesis is that analysis of these subgroups would reveal relevant biomarkers that would provide a better understanding of ASD phenotypic heterogeneity useful for further ASD studies. We address appropriate graph constructions suited for representing the ASD phenotype data. The sample population is drawn from a very large rigorous dataset: Simons Simplex Collection (SSC). Analysis of the results performed using graph quality measures, internal cluster validation measures, and clinical analysis outcome demonstrate the potential usefulness of resilience measure clustering for biomedical datasets. We also conduct feature extraction analysis to characterize relevant biomarkers that delineate the resulting subgroups. The optimal results obtained favored predominantly a 5-cluster configuration.
Microscale investigation of transverse tensile failure of fiber-reinforced polymer composites

In this study, two experimental approaches are used to understand fracture mechanisms that govern transverse tensile failure of fiber-reinforced polymer composites at the microscale. These observations are used to directly measure, and indirectly estimate, the magnitude and scatter of the transverse tensile strength, YT, and the associated effective flaw size, a0. To this end, static three-point bend tests are performed on pristine and notched 90° unidirectional IM7/8552 carbon-epoxy samples. In the pristine specimen study, tensile microcracks are observed to initiate well before the ultimate failure load used to compute YT is reached. In the notched specimen study, a comparison is made between experimentally measured strengths with known notch lengths and a linear elastic fracture mechanics solution. The fracture mechanics solution significantly over-predicts the apparent YT for notch lengths less than a ply thickness, suggesting that this approach may not be appropriate for estimation of transverse tensile strength at the microscale. The observations made in this study suggest that YT may not be a true material property, but rather, a structural property dependent on specimen geometry and microstructural variability.
Chapter 6 – Using the second law of thermodynamics

This chapter is concerned with the application of the second law of thermodynamics in various fields, especially in the field of thermal engineering. The second law of thermodynamics is applicable to all physical, chemical, biological processes, as well as to heat and work conversions. The second law analysis is briefly presented in the following areas such as heat and fluid flow, heat and mass transfer, chemical reactions and reacting flows, and separation. The chapter provides the second law guidelinessuch as: (1) do not discharge heat at high temperature to the environment; (2) do not heat refrigerated streams with hot streams; (3) hot or cold sources with temperatures far from the ambient are valuable; and (3) minimize the throttling of fluid flow, steam, or other gases. It describes various case studies that give the applications of the second law of thermodynamics in various fields. The second law analysis has been widely used for combined forced convective heat and mass transfer. Mainly two-dimensional duct with various boundary conditions for laminar and turbulent flows are investigated in the search for the thermodynamic optimum.
Film as Identity Exploration: A Multimodal Analysis of Youth-Produced Films

Background/Context: Researchers have begun to document and understand the work youth do as they compose in multiple media including video games, online virtual worlds, participatory fan cultural practices, and in the digital media arts. However, we lack mechanisms for analyzing the products, especially when it comes to understanding the relationship between storytelling and identity. Objective: In this article, I bring together prior research on youth-produced media, social semiotic analysis frameworks for analyzing these products and the formal analysis of films to construct an analytic framework for understanding youth-produced films as spaces for identity construction and representation. Research design: The research reported on in this article is the design and illustration of an analytic framework for understanding how youth construct and represent their identities through the films they make. The framework design begins with Kress and van Leeuwen’s (2006) work on the analysis of visual design as a set of semiotic resources for describing how we make meaning with multimodal texts. However, this work does little to depict how the specific tools of film both cinematic (e.g., editing, cinematography) and filmic (music, action) (Burn & Parker, 2003) are used to construct and communicate identities. Therefore, I turn to film theory to develop a coding scheme that can assist in the meaningful interpretation of the phases and transitions of youth-produced films. I then illustrate this framework in action by analyzing one youth-produced film, Rules of Engagement, as a multimodal product of identity. Conclusions/Recommendations: This analysis demonstrates how films like Rules of Engagement display the construction of a viable social identity primarily through the interactions among filmic elements. Specifically it is in the transition spaces between phases of the film where youth actively insert their understanding of how to represent complex portraits
Evaluation of a Training Program for Foster Parents of Infants with Prenatal Substance Effects

The lack of prepared and available foster parents for children with prenatal substance effects is of increasing concern to the child welfare field. Effective foster parent training is needed to assure infants are fostered by knowledgeable, skilled foster parents and that the foster parents feel supported and effective in taking on their responsibilities. The training was designed so that the foster parents would have opportunities to achieve highly specific learning objectives. True random assignment of subjects was impossible because of the voluntary nature of foster parent training; the samples of foster parents for both the treatment group and the comparison groups were therefore self-selected. The possibility exists that some foster parents who attended the training decided as a result of the training not to foster infants with prenatal substance effects. Infants with prenatal substance effects may require specialized care and foster parents need to be prepared to provide it.
Crime in an Affluent City: Applications of Risk Terrain Modeling for Residential and Vehicle Burglary in Coral Gables, Florida, 2004–2016

Risk Terrain Modeling (RTM) — an innovative geospatial approach to analyze the locations of high crime areas within cities— was used to analyze criminogenic spaces and identify the riskiest places contributing to vehicle and residential burglary in the city of Coral Gables, Florida from 2004 to 2016. Official crime incident data on residential and vehicle burglary were provided by the Coral Gables Police Department. We investigated the role of environmental predictors of crime by analyzing the effects of the designated riskiest places including alcohol vendors, car dealers, gas stations, bars, secondary/post-secondary schools, grocery stores, and restaurants. We identified risky places and their proximity to the occurrence of residential and vehicle burglary with a regression process using the RTM technique to determine the Relative Risk Values (i.e., weighted risk) that each risk factor had. We examined different temporal designations, including day and night, day of the week, and monthly intervals. Our results indicated that restaurants and grocery stores located in the downtown area and along the US 1 highway were higher risk locations for the occurrence of both types of crime throughout the city. The locations of risky places in the study area were spatially consistent with high crime areas, supporting our main hypothesis. The use of RTM with targeted community policing strategies could move policy from a reactionary approach to more proactive solutions to crime prevention. Concepts drawn from routine activity theory, as well as crime and place perspectives, both receive moderate empirical support for vehicle and residential burglary outcomes.
Evaluation of upper limb superficial venous percussion as a sign of anatomical location and venous permeability. A comparative study of superficial venous percussion to ultrasound findings on non-renal patients and on chronic kidney disease patients.

The objective of this study was to evaluate venous percussion in the upper limbs as a possible low-cost clinical sign that may contribute to physical examination of the superficial venous system and be useful in the evaluation for punctures and also for the construction of fistulas. Methods An analytical cross-sectional study with 70 individuals divided into two groups. Group A consisted of 35 volunteers who were being preoperatively prepared for the construction of arteriovenous fistula. Group B consisted of 35 non-renal patients selected by convenience. Each participant underwent physical examination, including venous percussion, of the dominant upper limb and then ultrasound. Interobserver agreement was assessed between a trained vascular surgeon performing percussion and fourth-year medical student. Accuracy, sensitivity, specificity, positive predictive value and negative predictive value of percussion were determined in relation to ultrasound. The agreement between the methods, venous percussion and venous duplex ultrasound was also evaluated by the Kappa index. Results The overall interobserver agreement for the percussion was 0.74 (95% CI 0.632 to 0.851). It was observed that the results were more favorable in the cephalic vein than in the basilic vein, emphasizing that the cephalic is more used in venous punctures, because of its anatomical location and visibility, and in fistula construction. The 35 percussions of the cephalic forearm vein in Group A resulted in a sensitivity of 1.0 (95% CI 0.63 to 1.00), specificity of 0.96 (95% CI 0.81 to 1.00), a positive predictive value of 0.89(95% CI 0.52 to 1.00) and a negative predictive value of 1.00 (95% CI 0.87 to 1.00), with an accuracy of 0.97 (95% CI 0.85 to 1.00) and Kappa index of 0.92 (95% CI 0.77 to 1.00) in relation to ultrasound. Overall, when all venous segments were analyzed in group A, the Kappa index of agreement between the percussion and the ultrasonography reached 0.56 (95% CI 0.401 to 0.72). All venous segments in Group A had a sensitivity of 0.54 (95% CI 0.37 to 0.70) and a specificity of 0.96 (95% CI 0.90 to 0.99). When all venous segments were analyzed in group B, the Kappa index of agreement between the percussion and the ultrasonography reached 0.48 (95% CI 0.34 to 0.62). All venous segments in Group B had a sensitivity of 0.70 (95% CI 0.59 to 0.79) and a specificity of 0.82 (95% CI 0.69 to 0.91). Conclusion Venous percussion of the upper limbs has a high positive predictive value and high specificity, when compared to ultrasound as a way to evaluate the patency and adequacy of the cephalic vein. Although there is not enough evidence to preclude ultrasound, percussion should definitely be included in the traditional physical exam evaluation of upper limbs superficial veins.
Value in Hepatitis C Virus Treatment: A Patient-Centered Cost-Effectiveness Analysis

Innovations in hepatitis C virus (HCV) therapy included in traditional comparative evaluations focus on sustained virologic response (SVR) without addressing challenges patients report beyond virologic cure. This study aims to evaluate the cost-effectiveness of HCV drug therapy with a patient-centered approach. An individual-based Markov model was constructed using guidance from a stakeholder advisory board (SAB), a patient Delphi panel, and published literature to evaluate direct-acting antivirals (DAAs) compared to no treatment. The United States (US) health sector and societal perspectives were considered for 10- and 20-year time horizons. Inputs for treatment costs and effectiveness reflect a generic regimen. Indirect costs used for the societal model included estimates from self-reported productivity in a matched-control sample. Beyond the traditional quality-adjusted life-year (QALY) health outcome, this study included two novel measures developed from the Delphi panel and SAB: infected life-years and workdays missed. All costs were measured in 2018 US dollars. Health sector costs and QALYs were higher in the treatment group in both 10- and 20-year models. Total infected life-years and workdays missed were reduced in the treatment group for both models. When costs of absenteeism, presenteeism, and patient/caregiver time were included, the DAA intervention was cost-saving at both 10 and 20 years. Health sector results were sensitive to drug costs and utility estimates for post-SVR health states. Societal results were sensitive to presenteeism estimates and drug costs. Treatment was cost-effective from a health sector perspective and cost-saving when including non-health costs such as patient/caregiver time and productivity.
Effect of UV-absorbing Contact Lenses on Conjunctival Ultraviolet Autofluorescence

The intended purpose of UV-absorbing contact lenses is to protect the cornea and posterior ocular structures from UV-induced damage. Few studies report conjunctival effects of UV-absorbing contact ...
Relationship between Lambl's excrescences and embolic strokes of undetermined source.

AbstractIntroductionAbout one-fourth of ischaemic strokes are classified as embolic strokes of undetermined source. Lambl’s excrescences are commonly seen on cardiac valves, and data are limited on...
The Great Mother of Life

To Rachel Carson, the sea is “the great mother of life.” Her essay “Undersea” (1937) describes “the vicissitudes of life on the ocean floor, where sunlight, filtering through a hundred feet of wate...
Fecal and Urinary Incontinence: Epidemiology and Etiology

The true epidemiology of combined urinary and fecal incontinence is difficult to assess. The social stigma associated with these conditions has made it difficult for physicians to adequately identify affected patients. As we learn more about the function of the pelvic floor and recognize the common etiology of both anterior and posterior compartment dysfunction, we will offer better and more comprehensive care to our patients.
On the Relationship between Poverty Segregation and Homelessness in the American City and Suburb

Although existing scholarship notes that homelessness thrives in concentrated poverty, models estimating the association between the intensity of residential poverty segregation and local homelessn...
High-performance soft wearable robots for human augmentation and gait rehabilitation

Abstract Wearable robots are designed to assist people, thus their operation is based on a highly dynamic human–robot interaction. In order to make this interaction as effective as possible, the design of an exoskeleton is subject to challenging requirements involving its mechanical components prior to the control algorithms. Actuator, transmission, and wearable structure play a crucial role in determining the performance of a wearable robot. Current high-performance exoskeletons leverage a new actuation paradigm, so-called quasi-direct drive (QDD) actuation, to enhance a safe and compliant behavior without renouncing a high torque density. This chapter goes through the principles behind this new enabling technology and provides demonstrations of its beneficial application on several wearable robots. Three diverse exoskeletal prototypes are showcased, which are designed to assist hip, knee, and back, respectively. Preliminary tests executed on healthy subjects confirm the impactful potential of the QDD actuation scheme: all the devices take advantage of low mechanical impedance, high backdrivability, and high torque to exhibit accurate force tracking during various activities.
How the COVID-19 Pandemic has changed multiple sclerosis clinical practice: Results of a nationwide provider survey.

Abstract Background The COVID-19 crisis has created unanticipated changes in health care delivery for people living with multiple sclerosis (MS). The pandemic's rapid evolution has resulted in a knowledge gap in how COVID-19 has affected MS clinical practice. Our objective was to understand how the COVID-19 pandemic has affected clinical practice patterns in a nationwide cohort of MS clinicians across the United States. Methods In collaboration with the National Multiple Sclerosis Society (NMSS), we developed a 28-item SurveyMonkeyTM electronic questionnaire exploring MS specialists’ perceptions of how COVID-19 has altered how they prescribe MS disease-modifying therapies (DMTs), provide telehealth and other services, and view issues affecting their own well-being including re-deployment to the front lines of COVID-19 care and availability of personal protective equipment (PPE). NMSS staff sent a recruitment email containing the electronic survey link to 188 clinicians who serve on regional NMSS Healthcare Provider Councils across the US, 86 (45.7%) of whom were MS specialist physicians. Results Eighty-six of 188 potential respondents (45.7%) from 32 US states completed the survey including 45 physicians (41 neurologists, 3 physiatrists and 1 family physician), 18 rehabilitation therapists, 7 psychologists, 6 nurse practitioners, 4 social workers, 2 physician assistants, 2 nurses and 2 health professionals from other disciplines. More than 80% of all respondents working on-site in a health care setting believed they had adequate PPE. More than 41% were able to distance safely from others at work. Nearly 10% of respondents reported they had been re-deployed to the front lines of COVID-19 patient care, and an additional 16.9% anticipated being re-deployed. Among the MS specialist physician subgroup, nearly one-third reported using telemedicine to provide over 75% of their clinical care. Only 16.7% believed COVID-19 had not changed how they prescribe DMTs. Therapies prescribed more often during the pandemic included β-IFNs (28.6% of prescribers), natalizumab (23.8%), glatiramer acetate (21.4%) and teriflunomide (19%). DMTs prescribed less often included alemtuzumab (64.3% of prescribers), cladribine (54.8%), ocrelizumab and rituximab (50%), and fingolimod and siponimod (40.5%). For at least some of their patients during the pandemic, some MS specialists reported suspending certain DMTs including alemtuzumab (21.4% of prescribers), ocrelizumab and rituximab (16.7%) and cladribine (11.9%). Others reported extending DMT dosing intervals for natalizumab (38.1%), fingolimod and siponimod (11.9%). Conclusions In this nationwide survey, MS specialist physicians and other clinicians serving on regional NMSS Healthcare Provider Councils across the US reported profound changes in how they are delivering MS care during the COVID-19 pandemic.
Nuclear Air-Brayton Power Cycles with Thermodynamic Topping Cycles, Assured Peaking Capacity, and Heat Storage for Variable Electricity and Heat

Electricity markets are changing because of (1) the addition of wind and solar generating capacity and (2) the goal of a low-carbon electricity grid. The large-scale addition of wind and solar phot...
Comprehensive Valuation of the Ecosystem Services of the Arctic National Wildlife Refuge

Ecosystem services (ES) have been well studied in most biomes, but the Arctic tundra has received little attention, despite covering over 10% of terrestrial Earth. Using established ES methodologies, we calculated values (in 2016 USD) for the United States Arctic National Wildlife Refuge, a region virtually undisturbed by humans, but slated for future oil and gas drilling. We estimated the Refuge is worth about 1957 USD/hectare/year, equal to over 15 billion USD annually. Globally important services, such as climate regulation (e.g., carbon storage) and non-use services (e.g., aesthetic information), contributed the most value and were similar to valuations from more productive ecosystems. Local services made smaller contributions to the total, but they remain vitally important to local indigenous cultures. Strikingly, a contingent valuation survey of US residents found that, after neutral educational information, willingness-to-pay to maintain the Refuge in its current state exceeded estimated values of the oil and gas deposits. Our study shows that citizens may value Arctic habitats beyond their traditional economic development potential. Our comprehensive ecosystem services valuation suggests that maintaining the Refuge in its current condition (i.e., de facto wilderness) with its full range of ES is more valuable to humanity compared to development for oil and gas.
Arrays of Microplasma-assisted Atomic Layer Deposition and Etching Free Patterning of Ga 2 O 3 Thin Film with Flexible DUV Photodetector

Microplasma arrays assisted atomic layer deposition (MALD) have been used to deposit gallium oxide (Ga 2 O 3 ) thin film on the rigid and flexible substrate in order to fabricate deep-ultraviolet (DUV) photodetector under 254 nm illumination.
Development of a Telepsychology Program for Parents of Pediatric Patients

Objective: Telepsychology represents a promising approach to treatment for individuals and families encountering barriers to traditional face-to-face health care, especially in the challenging context of the 2019 coronavirus disease (COVID-19). Implementing the necessary infrastructure to sustain telepsychology programs within health care institutions requires detailed attention to a variety of domains. Despite the growing use of telepsychology, logistical considerations for the development of such programs are often unclear. Method: In order to clarify considerations regarding the use of telepsychology within partnering health care institutions, we describe the process of developing a telepsychology group intervention with parents of pediatric patients. Results: The development of a telepsychology program for parents at a large children's health care institution is discussed across four developmental phases: (a) curriculum development, (b) clinical framework, (c) program logistics, and (d) protocol and training infrastructure. Conclusion: Due to the growing need for telepsychological interventions for parents, both practitioners and health care institutions are tasked with collaborating to develop well-designed programs that are aligned with clinical best practices.
Is There Limited Utility for Lifestyle Recommendations for Diabetes Prevention Among Overweight or Obese Depressed Patients

Background: Lifestyle interventions like diet and exercise are commonly recommended for diabetes prevention, but it is unclear if depression modifies the likelihood of adherence. We evaluated the relationship between depression high depressive symptomatology and adherence to lifestyle interventions among patients with prediabetes. Methods: We conducted an analysis of the nationally representative National Health and Nutrition Examination Survey (NHANES) 2017-2018. Adults, aged >18 years old who were overweight or obese (BMI >25) and had diagnosed or undiagnosed prediabetes (HbA1c 5.7-6.4) were included. Depressiveon symptomatology was classified by the Patient Health Questionniare-9 (PHQ-9). We used self-reported adherence to physician suggested lifestyle changes of diet and exercise. Results: In this nationally representative survey of overweight or obese adults with prediabetes, 14.8% also have depressionhigh depressive symptomatology. In unadjusted analyses, an interaction was observed with depression high depressive symptomatology acting as an effect modifier for adherence to exercise oriented interventions among patients with diagnosed prediabetes (p=.027). In logistic regressions, adjusting for age, sex, race, outpatient medical care in the past 12 months, and obesity, among patients with diagnosed prediabetes, depressed patients were less likely to attempt to exercise more (OR = 0.3127; 95% CI: 0.101, 0.9469) and no association between depression high depressive symptomatology and attempting to lose weight was observed (OR = 0.4550; 95% CI: 0.148, 1.420). Conclusions: The findings of this nationally representative study of US adults, depression high depressive symptomatology decreases the likelihood of adherence to exercise based lifestyle recommendations among patients with diagnosed prediabetes.
Dyadic recruitment in complementary therapy studies: experience from a clinical trial of caregiver-delivered reflexology.

Abstract Purpose As home-based care continues to be a growing trend in health care, involvement of friend and family caregivers in the management of illness becomes essential. However, before nurses can prepare caregivers to engage in various types of care, an evidence base needs to be established via randomized controlled trials (RCTs). Research suggests that recruiting cancer patients and their friend or family caregivers into RCTs presents challenges. The purpose of this paper is to illustrate the barriers to recruitment of patient–caregiver dyads into a RCT of caregiver-delivered reflexology and to recommend strategies to address such barriers. Methods This paper reports on a nurse-directed RCT that involved recruitment efforts unique to a caregiver-delivered reflexology protocol for advanced-stage breast cancer patients. Ineligibility due to caregiver-related reasons, consent among eligible patients (out of 551 approached patients), and reasons for refusal were analyzed. Results Almost one-third of patients were found to be ineligible due to the lack of a caregiver to participate with them and provide this form of social support. Among eligible patients, the consent rate for this dyadic study is much lower than that of previous RCTs of reflexologist-delivered reflexology that enrolled just patients, not dyads. Conclusion Implications for nursing practice and research include addressing the need for greater social support for patients and strategies for problem-solving refusal reasons during study enrollment.
The Effects of Load Carriage and Physical Fatigue on Cognitive Performance

In the current study, ten participants walked for two hours while carrying no load or a 40 kg load. During the second hour, treadmill grade was manipulated between a constant downhill or changing between flat, uphill, and downhill grades. Throughout the prolonged walk, participants performed two cognitive tasks, an auditory go no/go task and a visual target detection task. The main findings were that the number of false alarms increased over time in the loaded condition relative to the unloaded condition on the go no/go auditory task. There were also shifts in response criterion towards responding yes and decreased sensitivity in responding in the loaded condition compared to the unloaded condition. In the visual target detection there were no reliable effects of load carriage in the overall analysis however, there were slower reaction times in the loaded compared to unloaded condition during the second hour.
Basic Tenets for Coastal Ocean Ecosystems Monitoring

Describing and understanding how the coastal ocean works requires a systems science approach, including long-term observations and model simulations. These are prerequisites to predicting the outcomes of either natural or human-induced occurrences. Applications to societally relevant issues such as ecology, coastal resiliency, and alternative energy resources all have the coastal ocean circulation as their starting point. Ecology provides an example. The circulation is what unites nutrients with light, fueling primary productivity and higher trophic level interactions, and the circulation largely determines the water properties in which organisms reside. Ecology, in essence, integrates all processes responsible for organism success. A rationale and a design are developed for a comprehensive coastal ocean observing and modeling system off Florida's west coast. Applications are provided demonstrating the utility of such a coastal ocean observing and modeling system for addressing problems of societal importance.
Total magnetic charge for fast screening of highly contaminated UXO sites

The use of total normalized surface magnetic charge is proposed for the purpose of rapidly scanning highly contaminated unexploded ordnance (UXO) sites as well as for the application in UXO discrimination. Recent studies have demonstrated that in the electromagnetic induction (EMI) sensing considered here (tens of hertz up to several hundreds of kHz), the surface magnetic charge model (SMC) can reproduce EMI responses from any metallic object very quickly and accurately. In SMC the scattered magnetic field at any point outside a fictitious surface, surrounding the scatterers, is represented as a sum of quasi-static magnetic fields produced by equivalent elementary magnetic charges placed on the fictitious surface. In this work a fictitious plate, placed on the ground is used as fictitious surface. The amplitudes of SMC are determined by matching the scattered magnetic field to data at measurement grid points. Once the amplitudes of SMC are found then the total normalized magnetic charge is calculated, and it can be used effectively as a discriminator. In cases of highly contaminated sites, first data are taken for a cluttered site and its corresponding total magnetic charge is calculated and stored. Then, for any new nearby test site the total magnetic charge is calculated again. The total normalized charge for cluttered data is subtracted from the total for the new site, and thus the object is isolated from the clutter. Finally, for discrimination the object's total magnetic normalized charge is matched to cataloged/library data. Several numerical results are presented to demonstrate applicability of the total magnetic charge as a classifier in highly contaminates UXO sites.
A Fuzzy Approach to the Study of Human Reliability in the Petroleum Industry

This work presents a methodology for characterization of human reliability based on fuzzy sets concepts, aiming at reducing the possibility of human errors in oil refineries. It is suited for operation, maintenance and inspection activities in oil production and distribution units and is based on the API-770 guide for reduction of human errors, which identifies 64 performance factors. In order to assess the possibility of a human fault, the model analyses the elements that interact with each operator. It is possible, by this methodology, to obtain a human reliability index, to find out the problems that may constitute causes of human errors and to devise strategies for the control of potentially adverse impacts of interactions that add uncertainty and complexity to processes.
A Modern View of Heart Failure: Practical Applications of Cardiovascular Physiology

The sections in this article are: 1 Paradigmatic Shifts 2 Definition of Heart Failure 3 The Paradigm of Organ Physiology: The Failing Heart as a Defective Pump 3.1 Backward and Forward Failure 3.2 Systolic and Diastolic Dysfunction 3.3 Right and Left Heart Failure 3.4 The Neurohumoral Response in Heart Failure 3.5 Crossover Between Functional and Proliferative Signaling 3.6 Coupling Between the Failing Heart and the Circulation: Pressure–Volume Loops 3.7 Architectural Changes in the Failing Heart 4 The Paradigm of Biochemistry and Biophysics: The Failing Heart as a Weakly Contracting, Incompletely Relaxing Muscle 4.1 Inotropic and Lusitropic Abnormalities 4.2 Energy-Starvation 4.3 Molecular Alterations and Architectural Changes 5 The Paradigm of Gene Expression: The Failing Heart as an Abnormal Molecular Structure 5.1 Adaptive and Maladaptive Hypertrophy 5.2 Cardiac Myocyte Phenotypes 5.3 Shape Changes in the Cells of the Overloaded Heart 5.4 Myocardial Cell Death 6 Summary and Conclusions
A METHOD FOR EXPOSING LOBSTERS TO MULTIPLE SIMULATED HABITAT BIOGEOCHEMICALS AND TEMPERATURES

Abstract A flow-through experimental system was designed to simulate habitat conditions encountered by American lobsters (Homarus americanus) during an eutrophication-driven mass mortality in the Long Island Sound during 1999. Seawater for the system was chemically conditioned through gas exchange and the addition of inorganic salts, resulting in simultaneous control of multiple environmental variables including: temperature (±0.5°C), dissolved oxygen (±0.3 mg L−1), sulfide (±1 μM) and ammonium (±3 μM). The system consisted of eight gas-tight, 280-L tanks, each capable of accommodating 22 lobsters, supplied with 0.4 L min−1 animal−1 of conditioned seawater. Outflows were fitted with ozone and ultraviolet sterilization so that lobsters could be exposed to infectious pathogens in varying doses to study effects of habitat on disease resistance, without contaminating the environment. Shelters are supplied in excess and lobsters utilizing them may be monitored to observe behavioral and physiologic responses wi...
Effects of High-Pressure Processing at Low Temperature on the Molecular Structure and Surface Properties of β-Lactoglobulin

High-pressure processing (HPP) was utilized to induce unfolding of β-lactoglobulin (β-LG). β-Lactoglobulin solutions at concentrations of 0.5 mg/mL, in pH 7.5 phosphate buffer, were pressure treated at 510 MPa for 10 min at either 8 or 24 °C. The secondary structure, as determined by circular dichroism (CD), of β-LG processed at 8 °C appeared to be unchanged, whereas β-LG processed at 24 °C lost α-helix structure. Tertiary structures for β-LG, as determined by near-UV CD, intrinsic protein fluorescence spectroscopy, hydrophobic fluorescent probe binding, and thiol group reactivity, were changed following processing at either temperature. The largest changes to tertiary structure were observed for the samples processed at 24 °C. Model solutions containing the pressure-treated β-LG showed significant decreases in surface tension at liquid−air interfaces with values of 54.00 and 51.69 mN/m for the samples treated at 24 and 8 °C, respectively. In comparison, the surface tension for model solutions containing ...
Note on psychophysical discrimination with more than two stimuli.

H. D. Landahl's well-known theory of psychophysical discrimination between two stimuli (Psychometrica,3, 107–125, 1938) is generalized to the case ofn mutually inhibiting stimuli, such that all the corresponding reactions are mutually incompatible so that only one response at most can occur at a time. It is shown that while in the two-stimulus case a “no-response” situation does not necessarily need to occur, in the case ofn stimuli andn responses a “no-response” situation always occurs with finite probability. Therefore, there is a probabilityPi of the occurrence of each responsei as well as a probabilityPe of no response, with\(\sum\limits_i {P_i } + P_e = 1\). The probabilitiesPi andPe are expressed in terms of the intensities of then stimuliSi and in terms of then distribution functions of the fluctuations at then corresponding connections. The expressions are in the form of sums ofn-tuple integrals of the products of the distribution functions, the limits of integration being determined by the intensities of then stimuli.
Measurement of the depolarization ratio of Raman lines in liquids

Abstract A simple method is proposed for correcting the measured depolarization ratio in the liquid phase for the combined effects of convergence of the incident light and the refractive index of the sample. The method has been verified experimentally and used to indicate the effect of intermolecular interaction on the value of the depolarization ratio. The depolarization ratios for completely polarized and depolarized lines are predicted and shown to be uninfluenced by intermolecular interactions, whereas for partially polarized bands, the depolarization ratio may be affected by about 10 per cent.
Deep Inelastic Scattering: Experiments on the Proton and the Observation of Scaling

In late 1967 the first of a long series of experiments on highly inelastic electron scattering was started at the two-mile accelerator at the Stanford Linear Accelerator Center (SLAC) using liquid hydrogen and, later, liquid deuterium targets. Carried out by a collaboration from the Massachusetts Institute of Technology (MIT) and SLAC, the object was to look at large-energy-loss scattering of electrons from the nucleon (the generic name for the proton and neutron), a process soon to be dubbed deep inelastic scattering. Beam energies up to 21 GeV, the highest electron energies then available, and large electron fluxes made it possible to study the nucleon to very much smaller distances than had previously been possible. Because quantum electrodynamics provides an explicit and well-understood description of the interaction of electrons with charges and magnetic moments, electron scattering had, by 1968, already been shown to be a very powerful probe of the structures of complex nuclei and individual nucleons.
Kinetics of Degradation of Glutethimide

The hydrolysis of glutethimide (2-ethyl-2-phenyl-glutarimide) in buffered aqueous solutions in the pH range 1.5—8.0 has been studied. This region exhibited specific base catalysis. The overall rate may be expressed by the equation, rate = k ' (glutethimide) at constant pH. The energy of activation, corrected for heat of ionization of water, was calculated. A mechanism of hydrolysis is proposed.
Determination of the energetic cost of swimming from the analysis of growth rate and body composition in juvenile chinook salmon, Oncorhynchus tshawytscha.

1. 1. The standard metabolic rate was estimated to be 19.5 cal · kcal−1-day 1. 2. 2. The multiple regression of growth on swimming speed and ration size was significant (P < 0.001). The relationship was as follows: G = 22.22−2.85BL + 6.58R where G is growth in cal · kcal-day−1, BL represents swimming speed in body lengths-sec−1 and R denotes ration in % body wt.day −1, dry weight. The multiple correlation coefficient, R2, was 0.80. 3. 3. Unlike coho salmon, the net cost of swimming was independent of swimming speed. 4. 4. Fish in all groups experienced reduction of fat with exercise with the exception of the slowest speedhighest ration (1.0–1.9 BL · sec−1, 6%-day−1) group. 5. 5. Nearly all of the explained variation was accounted for by food consumption rate.
Tumorigenicity as a clinical hurdle for pluripotent stem cell therapies

Human pluripotent stem cells (PSCs) are a leading candidate for cell-based therapies because of their capacity for unlimited self renewal and pluripotent differentiation. These advances have recently culminated in the first-in-human PSC clinical trials by Geron, Advanced Cell Technology and the Kobe Center for Developmental Biology for the treatment of spinal cord injury and macular degeneration. Despite their therapeutic promise, a crucial hurdle for the clinical implementation of human PSCs is their potential to form tumors in vivo. In this Perspective, we present an overview of the mechanisms underlying the tumorigenic risk of human PSC-based therapies and discuss current advances in addressing these challenges.
Barriers to acute stroke therapy and stroke prevention in Mexican Americans.

Background and Purpose —The purpose of this study was to identify specific targets to improve acute stroke treatment and stroke prevention in the Mexican American (MA) community. Methods —A professional, academic survey research team provided structured questions and elicited responses from 719 subjects identified by random-digit dialing in the biethnic community of Corpus Christi, Texas. This community of approximately 300 000 is approximately half MA and half non-Hispanic white (NHW). The cooperation rate for the survey was 58%. Results —MAs (n=357) were younger, less well educated, and had lower family income than NHWs (n=362, P =0.001). MAs had a higher prevalence of diabetes mellitus ( P =0.001) but similar rates of hypertension, elevated cholesterol, and current tobacco use. MAs less commonly recognized that acute stroke therapy existed ( P =0.029), were less likely to acknowledge a time window for acute stroke treatment ( P =0.001), and were more reticent to say they would call 911 for stroke symptoms ( P =0.01) than NHWs. MAs were significantly less able to recall stroke symptoms and risk factors than NHWs. Only approximately 20% of both groups identified stroke as the No. 1 cause of disability. MAs expressed less confidence in their ability to prevent stroke ( P <0.001), more distrust in the medical establishment ( P =0.007), and more concern that money impedes their seeking medical care ( P <0.001). Conclusions —There are significant barriers to both acute stroke treatment and stroke prevention in MAs. This study identifies specific targets amenable for testing in an intervention project following confirmation by a methodology other than telephone survey.
Ion Track Shunt Effects in Multi-Junction Structures

Charge collection processes are discussed for heavy ion hits across multiple p-n junctions in bipolar transistor or CMOS structures. The concept of a resistive-like ion track shunt bridging two like conductivity regions is introduced and a first-order-model developed for the charge transported along the ion track shunt. This model is shown to be consistent with charge collection measurements on multi-junction CMOS-like structures. It is found that the charge collection at a given p-n junction is influenced and can even be changed in sign by voltages present at a second p-n junction when the ion track penetrates both junctions. This has important consequences for the design of radiation hard integrated circuits and such ion track shunt effects become more important as device dimensions are scaled to smaller values.
A study of sine-wave contrast sensitivity by two psychophysical methods

In the literature on visual contrast thresholds for sine wave gratings, little attention has been paid to the psychophysical methods used to obtain these spatial-frequency response curves. Here we report a comparison of such data obtained by two quite different psychophysical methods, but otherwise under identical conditions, using five Ss. Both experiments were run by computer: (1) In the method of adjustments, the computer program merely controls the order of the stimuli and records S’s contrast settings. (2) In the forced-choice staircase (FCS) technique, the program determines how often S can discriminate the sinusoidal grating from a uniform field, informs S of his accuracy, controls the stimulus contrast on the basis of S’s preceding responses, and brackets his threshold by a series of successive approximations. Method 2 eliminates criterion effects that occur in Method 1, and hence tends to minimize individual differences. However, the FCS technique requires an order of magnitude more observing time to obtain equally smooth contrast sensitivity curves. FCS also increases the/overall sensitivity of some Ss by as much as five times, but it does not significantly change theshape of the contrast sensitivity curve; both methods show strong effects of lateral inhibition at low spatial frequencies.
Esophageal carcinoma: pre-operative staging and evaluation of anastomotic recurrence

Survival after surgical resection of esophageal carcinoma is highly related to stage. The latest staging classifications (UICC/AJCC, 1987/1988) use the TNM system. Accumulating data show endoscopic ultrasonography (EUS) to be consistently more accurate than CT in pre-operative staging of depth of tumor invasion. Detailed images of the esophageal wall obtained by EUS allow accurate staging even in early cancer where CT is ineffective. EUS is also more accurate than CT in staging regional lymph nodes, but is less accurate than CT in staging distant metastases due to tumor stenosis in some patients and limited depth of field. EUS has also been shown to be accurate in diagnosing post-operative recurrence of cancer in the area of the surgical anastomosis. EUS represents a major advance in the clinical staging of esophageal cancer.
Simple analytical models for estimating the queue lengths from probe vehicles at traffic signals

As mobile traffic sensor technology gets more attention, mathematical models are being developed that utilize this new data type in various intelligent transportation systems applications. This study introduces simple analytical estimation models for queue lengths from tracked or probe vehicles at traffic signals using stochastic modeling approach. Developed models estimate cycle-to-cycle queue lengths by using primary parameters such as arrival rate, probe vehicle proportions, and signal phase durations. Valuable probability distributions and moment generating functions for probe information types are formulated. Fully analytical closed-form expressions are given for the case ignoring the overflow queue and approximation models are presented for the overflow case. Derived models are compared with the results from VISSIM-microscopic simulation. Analytical steady-state and cycle-to-cycle estimation errors are also derived. Numerical examples are shown for the errors of these estimators that change with probe vehicle market penetration levels, arrival rates, and volume-to-capacity ratios.
Pulmonary metastases in guinea pigs as a consequence of dermal implantation of line-10 tumor cells

Metastases to the lungs of guinea pigs occurred at high frequency as a consequence of intradermal implantation of tumor cells derived from the syngeneic hepatocellular carcinoma line-10. Surgery had a major influence on the proportion of guinea pigs found to have pulmonary metastases at necropsy. Without surgery all guinea pigs died with extensive lymph node metastases; macroscopic pulmonary metastases were present in a minority of the animals. Animals treated by excision of dermal tumors survived longer than untreated animals, and macroscopic pulmonary metastases were present in the majority of the animals. Animals treated by excision of dermal tumor and regional lymph nodes were rendered tumor-free. The data suggest that lymph node metastases were the most likely source of the tumor cells that spread to the lungs in animals from whom the dermal tumor transplant had been removed.
Effects of cigarette smoking through a partially occluded filter

The effects of a commercially available corn syrup solution that is applied to the filter end of a cigarette causing an occlusive barrier to cigarette smoke were evaluated. The manufacturer claims that the solution reduces exposure to nicotine, carbon monoxide (CO), and other constituents of tobacco smoke and may aid in smoking cessation by providing a means of gradual nicotine dose reduction. Nineteen volunteers (10 men) smoked commercial cigarettes treated with 0, 1, 2, or 3 drops of the corn syrup solution in a double-blind, crossover experiment. Increases in plasma nicotine after smoking averaged 13.3, 10.5, 9.7, and 6.0 ng/ml in the 0, 1, 2, and 3 drop conditions, respectively. In the 3 drop condition, there was a significant reduction in exhaled CO levels. Subjects reported increased difficulty in cigarette draw and a trend toward decreased strength as a function of the number of drops applied. Cardiovascular and EEG measures of smoking were not significantly affected by the application of the drops. Cigarettes treated with 0, 1, 2, or 3 drops of the solution were machine smoked using methods of the Federal Trade Commission (FTC); nicotine yields were 1.0, 1.0, 0.78, and 0.73 mg of nicotine. These results indicate that Take Out drops reduce exposure to nicotine and other constituents of tobacco smoke from a single cigarette.
Co-elementary equivalence for compact Hausdorff spaces and compact abelian groups

Abstract The notions of elementary equivalence and elementary mapping in first order model theory have category-theoretic reflections in many well-known topological settings. We study the dualized notions in the categories of compact Hausdorff spaces and compact abelian groups.