cssi/SciSciGPT-SciSciNet huggingface dataset:
Coupling Reduced Order Models via Feedback Control for 3D Underactuated Bipedal Robotic Walking

This paper presents a feedback control methodology for 3D dynamic underactuated bipedal walking, that couples an actuated spring-loaded-inverted-pendulum (aSLIP)for forward walking and the passive Linear Inverted Pendulum (LIP)for lateral balancing. The applications of the reduced order models are twofold. First, we utilize aSLIP optimization to design optimal leg length and angle trajectories, and use the LIP dynamics to find desired boundary condition for lateral roll. Second, we present two feedback stabilization laws which are based on the reduced order models and applied on the full robot to stabilize the sagittal walking and lateral balancing separately. The ultimate feedback controller on the full order 3D walking robot is implemented via control Lyapunov function based Quadratic Programs (CLF-QPs). In particular, the reduced order models are used to approximate the underactuated dynamics and plan desired trajectories that are tracked via CLF-QPs. The end result is 3D underactuated walking, demonstrated in simulation on the bipedal robot Cassie.
Expanding the Clostridioides difficile Genetics Toolbox

Clostridioides difficile genetics has rapidly advanced in recent years thanks to the development of tools for allelic replacement and transposon mutagenesis. In this Journal of Bacteriology issue, Muh et al extend the genetics toolbox by developing a CRISPRi strategy for gene silencing in C. difficile (U.Muh, A. G. Pannullo, D. S. Weiss, and C. D. Ellermeier, 2019, J Bacteriol 201:e00711-18. . https://doi.org/10.1128/JB.00711-18). The authors demonstrate the tunability and robustness of their CRISPRi system, highlight its utility in studying essential gene function, and discuss exciting new possibilities for dissecting C. difficile physiology.
Are housing characteristics experienced by children associated with their outcomes as young adults

Abstract We study the association between childhood housing characteristics and homeownership and a set of behavioral outcomes of young adults. The primary data set is the National Longitudinal Study of Youth-1979 cohort (NLSY79) and the Child and Young Adult surveys of the children of the female NLSY79 respondents, augmented with a record of the characteristics of dwellings occupied by respondents and their children throughout childhood. We find that living in an owner-occupied home during childhood is positively associated with young adults’ educational attainment, and is negatively associated with teen pregnancy, criminal convictions, and the likelihood of being on welfare. In contrast, a measure of residential crowding during childhood has an independent relationship only with youths’ criminal convictions. We explore several mechanisms that could explain these long run patterns, including unobserved parental heterogeneity and childhood cognition.
Equity investigation of attitudinal shifts in introductory physics

Modeling instruction supports equity in student attitudinal shifts in introductory physics.
Microbial bioconversion of thermally depolymerized polypropylene by Yarrowia lipolytica for fatty acid production

Plastic production and waste generation will continue to rise as nations worldwide grow economically. In this work, we detail a pyrolysis-based bioconversion process for polypropylene (PP) to produce value-added fatty acids (FAs). PP pellets were depolymerized by pyrolysis, generating oil that consisted of mainly branched chain fatty alcohols and alkenes. The oil was mixed with biodegradable surfactants and trace nutrients and mechanically homogenized. The resulting medium, OP4, was used for fermentation by Yarrowia lipolytica strain 78-003. Y. lipolytica assimilated > 80% of the substrate over 312 h, including 86% of the fatty alcohols. Y. lipolytica produced up to 492 mg L-1 lipids, compared with 216 mg L-1 during growth in surfactant-based control medium. C 18 compounds, including oleic acid, linoleic acid, and stearic acid, were the predominant products, followed by C 16 compounds palmitic and palmitoleic acids. Two percent of the products was C 20 compounds. The majority of the products were unsaturated FAs. Growth on hydrophobic substrates (OP4 medium, hexadecane) was compared with growth on hydrophilic substrates (glucose, starch). The resulting FA profiles revealed an absence of short-chain fatty acids during growth on hydrophobic media, findings consistent with ex novo FA biosynthesis. Overall, FA profiles by Y. lipolytica during growth in OP4 medium were similar to FA profiles while growing on natural substrates. The process described here offers an alternative approach to managing postconsumer plastic waste.
Improving the Outcomes of Hispanics in AP Computer Science

This lightning talk describes a proof of concept research project funded by a Google CS Education (CS-ER) Research grant. The project focuses on pedagogical interventions aimed at improving the outcomes of English Language Learners (ELLs) in Advanced Placement Computer Science. The research underway examines the use of Sheltered Instruction (SI), a model from English as a Second Language (ESL) and bilingual education, used in mainstream classrooms across other content areas, in the AP CSA and AP CSP classroom. Strategies and pedagogy from the Sheltered Instruction model are being infused into AP Computer Science curriculum and used in classrooms in participating districts. The districts have been selected to include a range of ELLs and native English speakers. The impact of this approach will be measured by comparing the AP CS exam scores of students in the participating districts with the national and state AP CS exam scores. This lightning talk will focus on the pedagogy development which has taken place and preliminary findings from two cohorts of AP CS and AP CSA teachers, in particular the impact and changes to the teacher's development of CS education lessons and in-class lesson delivery. The project is an interdisciplinary collaboration between faculty from the School of Computer Science and the School of Curriculum and Teaching.
The Turbulent Aether

My first encounter with Feza occurred probably in the summer of 1959 at BNL. We were among the summer visitors there. Recognizing his name on the door of his office, I went in and introduced myself, because I knew his work on the so-called Pauli-Gursey transformation, and also because I had heard a lot about him from K. Nishijima. In any case, I immediately felt close to him. I don’t think he has changed much over the years, nor has my feeling toward him.
Phase I Single-Blinded Randomized Controlled Trial Comparing Balance and Aerobic Training in Degenerative Cerebellar Disease.

Introduction Primary deficits in individuals with cerebellar degeneration include ataxia, unstable gait, and incoordination. Balance training is routinely recommended to improve function whereas little is known regarding aerobic training. Objective To determine the feasibility of conducting a randomized trial comparing balance and aerobic training in individuals with cerebellar degeneration. Design Assessor blinded randomized control phase I trial. Setting Assessments in medical center, home training. Participants Twenty participants with cerebellar degeneration were randomized to home balance or aerobic training. Intervention Aerobic training consisted of 4 weeks of stationary bicycle training, five times per week for 30-minute sessions. Home balance training consisted of performing the same duration of easy, moderate, and/or hard exercises. Outcome measures Scale for the Assessment and Rating of Ataxia (SARA), maximal oxygen consumption (VO2 max), Dynamic Gait Index, Timed Up and Go, gait speed. Results All 20 participants completed assigned training with no major adverse events. Seven of each group attained target training duration, frequency, and intensity. Although both groups had significant improvements in ataxia severity, balance, and gait measures, there were greater improvements in individuals who performed aerobic training in ataxia severity and maximal oxygen consumption when compared to balance training. The effect size for these outcome measures was determined to be large, indicating a phase II trial comparing the benefits of aerobic and balance training was feasible and required 26 participants per group. Improvements in SARA score and VO2 max remained in the aerobic training group at 3 months posttraining, but these improvements were trending back to baseline. In contrast, all balance group measures for pretraining and 3 months posttraining were statistically similar. Conclusions A phase II trial comparing balance and aerobic training in individuals with cerebellar degeneration is feasible. Benefits trended back toward baseline after training stopped, although benefits of longer duration exercise programs still need to be determined.
Inter-Relations Between Ethnic-Racial Discrimination and Ethnic-Racial Identity Among Early Adolescents

The authors examined whether the longitudinal inter‐relations between ethnic‐racial discrimination and ethnic‐racial identity vary according to the perpetrator of discrimination. The authors used three waves of data from early adolescents (n = 387; ages 11–12 at Wave 1) to assess the strength and direction of relations between perceived discrimination from non‐school adults and peers vis‐a‐vis ethnic‐racial identity exploration, commitment, private regard, and public regard. Cross‐lagged autoregressive path analyses showed that more frequent discrimination, regardless of source, had reciprocal and significant longitudinal inter‐relations with exploration and public regard. Peer discrimination predicted lower commitment and private regard 1 year later, whereas non‐school adult discrimination did not. Implications are discussed in relation to the role of peers and ethnic‐racial identity processes. [ABSTRACT FROM AUTHOR]
A pilot study of neonatal GALT gene replacement using AAV9 dramatically lowers galactose metabolites in blood, liver, and brain and minimizes cataracts in GALT-null rat pups

Classic galactosemia (CG) is a rare metabolic disorder that results from profound deficiency of galactose-1-P uridylyltransferase (GALT). Despite early detection by newborn screening and rapid and lifelong dietary restriction of galactose, which is the current standard of care, most patients grow to experience a broad constellation of long-term complications. The mechanisms underlying these complications remain unclear and likely differ by tissue. Here we conducted a pilot study testing the safety and efficacy of GALT gene replacement using our recently-described GALT-null rat model for CG. Specifically, we administered AAV9.CMV.HA-hGALT to seven GALT-null rat pups via tail vein injection on day 3 of life; eight GALT-null pups injected with PBS served as the negative control, and four GALT+ heterozygous pups injected with PBS served as the positive control. All pups were returned to their nursing mothers, weighed daily, and euthanized for tissue collection 2 weeks later. Among the AAV9-injected pups in this study, we achieved GALT levels in liver ranging from 64% to 595% wild-type, and in brain ranging from 3% to 42% wild-type. In liver, brain, and blood samples from these animals we also saw a striking drop in galactose, galactitol, and gal-1P. Finally, all treated GALT-null pups showed dramatic improvement in cataracts relative to their mock-treated counterparts. Combined, these results demonstrate that GALT restoration in both liver and brain of GALT-null rats by neonatal tail vein administration using AAV9 is not only attainable but effective.
Federal Election Commission Divided: Measuring Conflict in Commission Votes Since 1990

This article investigates conflict on the Federal Election Commission (FEC). A long literature has documented the polarization of elites in Congress, in state legislators, and among justices on the...
Current Knowledge and Opinions of Medical Trainees Regarding PSA Screening.

After 2008 and 2012 USPSTF recommendations against PSA screening, studies revealed a decline in screening rates and trend towards more advanced disease at presentation. After revision of this recommendation in 2017, PSA screening guidelines remain inconsistent and controversy still exists about its clinical utility. We seek to better understand the knowledge of medical trainees regarding this fundamental controversy and gain better insight into what they are being taught regarding this topic. Participants were medical students (n = 66) and residents (n = 60) from a single institution. REDCap software was used for informed consent, survey distribution, and data collection. Variables measured included PSA clinical knowledge, awareness of the PSA guideline changes, and attitudes, confidence, and viewpoints on use of PSA screening in clinical practice. More than 60% of medical trainees reported little or no knowledge of PSA screening guidelines. Although residents reported more knowledge than medical students, actual assessed knowledge of PSA screening did not differ between groups. Trainees reported receiving education primarily from other healthcare professionals and didactics, with some self-learning online. Though confidence was low overall, residents were more confident than medical students in discussing PSA screening with patients. The majority of respondents wanted more information about PSA testing, with medical students particularly interested in diagnosis/detection, treatment, and survival. Overall, opinions towards PSA testing as an aid were generally positive. Better education about the current PSA screening guidelines for medical trainees is imperative, particularly given that shared decision-making is of great importance when counseling patients on cancer screening.
One Sequin at a Time: Lessons on State Constitutions and Incremental Change from the Campaign for Marriage Equality

State constitutional litigation can be a powerful tool to advance a robust and proactive civil rights agenda at a time when opportunities for creating progressive change in federal courts is imperiled. The LGBTQ campaign for marriage equality serves as a lesson in the effectiveness of state constitutional litigation to create incremental change and move public opinion in the face of a hostile federal court system. This Article first engages readers unfamiliar with the complexities of state constitutional law in an overview of judicial federalism and the theoretical potential of state courts to establish or advance rights independently of the federal judiciary. It then offers a lesson on this potential from a particular period of time in the campaign for marriage equality (1986-2004), in which advocates for LGBTQ rights avoided litigating before an unfriendly federal judiciary, and instead strategically sought out incremental gains in state courts. This Article posits that this period in the LGBTQ rights movement was critical in both providing an intellectual framework for federal marriage equality litigation and, perhaps more importantly, significantly altering the American sociopolitical landscape to become far more willing to accept same-sex relationships as worthy of recognition under the law. The Article contributes to the discourse on civil rights by placing focus on state constitutional litigation (an undertheorized area of scholarship in comparison to the attention paid to the federal Constitution), and by specifically noting the significance of LGBTQ rights litigation to our understanding of the potential for state constitutions to create progressive change.
Language teacher candidates’ SFL development: a sociocultural perspective

Few studies in language teacher education programs provide insight on how knowledge of Systemic Functional Linguistics (SFL) is developed by teacher candidates to support their metalinguistic aware...
A portrait of environmental integration in United States K-12 art education

In recent years, scholars have increasingly recognized the value of the arts for furthering the aims of environmental education (EE). Likewise, art education scholars have noted the affinity betwee...
Do Court Decisions Drive the Federal Trade Commission’s Enforcement Policy on Merger Settlements?

Mergers are generally conglomerate in nature with only minor (if any) horizontal overlaps. Under U.S. law, an enforcement agency may challenge any anticompetitive aspect of the merger and the consequent delay associated with litigation would impose costs on the firm. These costs may give the enforcement agency “leverage” to extract a settlement even when the firm would prevail in court. This paper explores whether the FTC’s decisions to challenge transactions approximate the case law. We find that the representative enforcement regimes of the FTC and the courts are remarkably similar, although the FTC credits efficiencies, while courts consider buyer sophistication as a mitigating factor.
Health-related quality of life in children with chronic kidney disease is affected by the number of medications.

The number of medications could serve as a surrogate for burden of care at home and may affect health-related quality of life (HRQoL) in children with chronic kidney disease (CKD). Using baseline data from the Chronic Kidney Disease in Children (CKiD) Study, we modeled HRQoL scores, self-reported by the child (if ≥ 8 years old) and/or caregiver (all children) on unique counts and administrations of CKD- and non-CKD-related medications, using multivariate linear regression. Heterogeneity of associations between HRQoL and medication burden by age group (≥ 8 vs. < 8 years old) were explored. 734 participants median age 11 years, disease duration 8 years, median eGFR 53 mL/min/1.73 m2, 61% male, 22% African-American, 31% glomerular disease were prescribed median 3 unique CKD-related medications. Regarding HRQoL assessment, 201 children were < 8 years old and had only parent-proxy HRQoL score; 533 children ≥ 8 years of age had both child and parent-proxy scores. Overall, parents of children < 8 years old reported higher HRQoL scores than parents of older children: 84 vs. 76. However, in a unified multivariate regression model, HRQoL scores of children < 8 years showed greater decreases as the number of CKD-related medications increased compared to scores for children ≥ 8 years old. Average HRQoL scores reported by parents of younger CKD children were higher than those of older CKD children but decreased more with increased CKD medication counts than scores of older children. Considerations of HRQoL may be of particular importance for clinicians and caregivers when managing chronic disease comorbidities in younger children.
Craniomaxillofacial Fractures in Children

SUMMARY The pattern of craniomaxillofacial fractures seen in children varies with their evolving craniofacial anatomy and for this reason requires different treatment strategies from those in adults. Facial fractures in children may go unrecognized as a result of incomplete communication with the patient, inadequate radiographic examination in the restless child, or late presentation of the patient by the family. The team approach to pediatric craniofacial fracture management, the more frequent use of open reduction techniques and primary bone grafting when indicated, and the use of more stable forms of fracture fixation are factors that have revolutionized the treatment and outcome of pediatric facial fractures. The use of stable forms of fracture fixation may overcome the need for tracheostomy in the multiple-systems traumatized patient, decrease the incidence of TMJ ankylosis when multiple jaw fractures are present, limit the incidents of infection and malunion in difficult fixation cases, and allow improved oral hygiene and patient comfort during fracture healing.30 Although plate-and-screw internal fixation in the growing facial skeleton solves many problems encountered in the past, less rigid forms of fixation are required in children than in adults. The use of heavy reconstruction plates or compression fracture plates is not indicated. The use of miniplates or microplates is more appropriate. Self-tapping screws are preferred and are often placed unicortically. Late sequelae of pediatric fractures occur even when appropriate and prompt treatment is instituted. The effects of the trauma event, as well as of the surgical intervention or lack of treatment, on growth and development must be considered. Long-term follow-up by appropriate practitioners is mandatory to monitor these events.
Clinical Pharmacology Regulatory Sciences in Drug Development and Precision Medicine: Current Status and Emerging Trends

In the regulatory setting, clinical pharmacology focuses on the impact of intrinsic and extrinsic factors on inter-patient and intra-subject variability in drug exposure and response. This translational science contributes to the understanding of the benefit-risk profile in individual patients and the development of relevant therapeutic monitoring and management strategies. Clinical pharmacology also plays a major role in the development and qualification of drug development tools. This article presented some recent examples to illustrate the important roles of clinical pharmacology in drug development and evaluation. In addition, emerging trends in clinical pharmacology regulatory sciences were also discussed, including the Model-Informed Drug Development (MIDD) pilot program, the use of real-world data to generate real-world evidence, and leveraging advances in basic, biomedical, and clinical science into useful tools for drug development and evaluation. Continued advances in clinical pharmacology can be the basis of more rational and efficient drug development and improved access to new drug treatments that are tailored to the patient to achieve better efficacy and safety.
Religious Certainty as Social Capital

Recent scholarship on the social embeddedness of religion indicate that religious choices are often best explained through social ties, and religious belief and practice is influenced by congregational embeddedness. Berger’s theory of secularization argued that plausibility structures were maintained by interactions with others with the same worldview, and that outgroup ties can reduce one’s certainty in religion and be detrimental to the religious group. Taken together these approaches suggest that religious certainty functions like Coleman’s conceptualization of social capital. The purpose of this present study is to begin to conceptualize religious certainty as a form of social capital: something that inheres in social relationships and serves as a resource for future religious action of the individual; as well as potentially serving a resource for congregations. Using the Baylor Religion Study 2005 data I operationalize religious certainty as the certainty in the belief of the existence of God, and then perform logistic regression on certainty in God’s existence using social ties variables. Then I operationalize religious participation as attendance and run a multiple regression on attendance using certainty in the belief of God as an independent variable. The findings from the logistic regression on certainty indicate support for the hypotheses concerning social ties and certainty. The study finds that family religiosity and the number of friends one has who attend the same congregation the higher odds of certainty; whereas and the number of non-religious friends one has decreases the odds of certainty in the existence of God. The multiple regression on attendance suggests that religious certainty, net of all other variables, has a strong positive influence on attendance. The results offer preliminary support for the argument: religious certainty does in fact appear to be a form of social capital since it inheres in social relationships and serves as a resource for individual action. This has important implications for congregations as those with higher stocks of social capital will have greater resources for religious action. It also offers some empirical support for the microfoundations of Berger’s theory of secularization.
A Modern, American Courbet: Roy Lichtenstein’s European Rise to Fame, 1963-1966

Taking on Roy Lichtenstein’s European rise to fame, my paper describes how his work arrived in Western Europe during the 1963 Crisis of Abstract, when Europeans were turning their attention to Realism anew. It then explains that they appreciated his engagement with contemporary reality. Moreover, Lichtenstein’s popular imagery, colorful palette, and mechanized style appealed to them as a reflection of US-American civilization, whose influence was then at its pinnacle in Europe. They regarded him as a modern, American Courbet. His success was thus less “the triumph of American art” than the triumph of a European idea of the United States.
The NIEHS DR2 Network: Addressing COVID-19 Environmental Health Issues Through a Multi-Institution Academic Community of Practice

BACKGROUND AND AIM: The National Institute of Environmental Health Sciences (NIEHS) Disaster Response Research (DR2) Network is a network of collaborative investigators across the United States rep...
Dielectric properties of 0.65PbMg1/3(Nb(1−x)Tax)2/3-O3-.35PbTiO3

Abstract Lead magnesium niobate-lead titanate crystalline solutions 0.65PbMg1/3Nb2/3O3-0.35PbTiO3 (PMN-PT) have been investigated in this paper. The effect of tantalum partially substituting niobium (0.65PbMg1/3(Nb(1−x)Tax)2/3O3-0.35PbTiO3 (PMNTa-PT)) on dielectric properties has been studied. It was found that the transition temperature appears at 170–180°C for all the samples with and without doping. Doping 10% tantalum in 0.65PMN-0.35PT did not show the significant effect on the transition temperature. The ferroelectric characteristics were viewed from the results of dielectric measurement on samples without doping tantalum, i.e. sharp dielectric constant peak, and less frequency dispersion. The samples with 10% tantalum substitution of niobium (x=0.1) show more relaxor properties. It has broader dielectric constant peak and stronger frequency dispersion than that of the samples without doping. The samples with Ta-doping also show less frequency dependence than that of those without doping.
Letter from the Editor: Reviewers Needed

The Online Journal of Rural Nursing and Health Care is the official Journal of the Rural Nurse Organization. It is an electronic journal and can be accessed at http://www.rno.org/journal/index.htm. It is a refereed journal and is indexed in CINAHL and has an international readership. To complete the review processes necessary for a refereed journal there must be a volunteer panel of reviewers to judge the quality and appropriateness of submissions for publication. The review panel has international members and the published articles are from around the world. However, as peoples’ lives change their ability to provide this valuable service to the Online Journal of Rural Nursing and Health Care changes. That leaves the editorial in constant need of committed reviewers. If you would be interested in serving on the review panel of the Online Journal of Rural Nursing and Health Care please email a note of interest and your resume to the Editor, Dr. Jeri Dunkin, at jdunkin@bama.ua.edu.
Engaging Children's Spontaneous Questions about Social Diversity

In this article the author shares conversations she has had with elementary students inquiring about her gender identity to make visible the daily-ness of conversations about sameness and difference and to surface her own struggles with, and pedagogical deliberations about, these conversations. The conversations are conceptualized as both the unit of participation and analysis. Analyzing transcripts of conversations creates a tool for teacher reflection and proactively surfaces discussions about identity and social participation.
Reduced expression of the cystic fibrosis transmembrane conductance regulator gene in the hypothalamus of patients with Alzheimer's disease.

Background The cystic fibrosis transmembrane conductance regulator (CFTR) gene encodes an approximately 150-165 kD glycoprotein that is mutated in individuals with cystic fibrosis. Previous studies demonstrated expression of the CFTR gene in the hypothalamus, suggesting a potential role for this molecule in the regulation of systemic metabolic functions. Individuals with cystic fibrosis often exhibit wasting and marked reductions in body fat content. Since the hypothalamus is a late target of neurodegeneration in Alzheimer's disease (AD), we postulated that patients with end-stage AD and bodily wasting would have reduced levels of CFTR expression in the hypothalamus. Methods CFTR mRNA and protein were examined in postmortem hypothalamic tissue from 11 AD and 7 aged controls using in situ hybridization and immunohistochemical staining. Standardized sections that included the supra-optic, paraventricular, anterior, and ventromedial nuclei, and the lateral hypothalamus were studied. Results The density of CFTR+ neurons and the intensity of the CFTR hybridization signals were strikingly reduced in AD. Immunohistochemical staining studies demonstrated CFTR immunoreactivity most prominently distributed in small clusters of neurites (5 to 20 in number). Digital image quantification showed that the density of CFTR+ neurites was significantly reduced in AD relative to aged control samples (P=0.001). However, there was no evidence for selective involvement of particular hypothalamic nuclei. Conclusions CFTR gene expression is down-regulated and its corresponding immunoreactivity reduced in AD relative to control hypothalamic tissue. Reduced CFTR expression in the hypothalamus may represent an important mechanism by which AD neurodegeneration contributes to body wasting in the late stages of disease.
Cortical cerebral blood flow cycling: anesthesia and arterial blood pressure

Cycling of various cerebral metabolic substances, arterial vascular diameter, and flow has been noted by many workers at a frequency near 0.1 Hz. Suspicion that this phenomenon is dependent on the type of anesthesia led us to investigate the occurrence of cerebral blood flow (CBF) cycling with different anesthetics. Fifteen Sprague-Dawley rats were anesthetized with either pentobarbital (n = 5, 40-50 mg/kg), alpha-chloralose (n = 5, 60 mg/kg), or halothane (n = 5, 1-0.5%). Body temperature was maintained at 37 degrees C. Femoral arterial and venous catheters were placed, and a tracheotomy was performed, permitting artificial ventilation with 30% O2-70% N2. A closed cranial window was formed over a 3-mm diameter craniotomy. Mean arterial pressure (MABP), arterial partial pressures of CO2 and O2 (PaCO2 and PaO2), and pH were controlled and stabilized at normal values. CBF was determined using laser Doppler flowmetry. To induce cycling, MABP was transiently and repeatedly lowered by exsanguination. Fast Fourier analysis of selected 64-s flow recordings (n = 38) was performed. CBF cycling was observed, independent of the type of anesthesia, in all animals. In 36 epochs, cycling was induced when MABP was reduced to a mean pressure of 65 +/- 1.5 mmHg. The mean frequency and amplitude were 0.094 +/- 0.003 Hz and 6.6 +/- 0.5%, respectively. Cycling occurred without blood withdrawal in two epochs. With the use of the blood-withdrawal epochs (n = 36), all three anesthetics shared a common linear slope between amplitude and blood pressure (P < 0.02) and blood pressure change (P < 0.01). Pentobarbital differed from alpha-chloralose and halothane in the relation between cycling frequency and blood pressure. Only pentobarbital exhibited correlation between frequency and blood pressure (P < 0.02) and blood pressure change (P < 0.001). The occurrence of these oscillations is not related to the type of anesthesia, and they usually occur at MABP values that are near or just above the lower limit of autoregulation. At this pressure level, CBF oscillations would suggest that vasoconstrictive and dilatory forces are no longer in balance, but alternatively vying for control.
Disease-associated F198S mutation increases the propensity of the recombinant prion protein for conformational conversion to scrapie-like form

The critical step in the pathogenesis of transmissible spongiform encephalopathies (prion diseases) is the conversion of a cellular prion protein (PrP(c)) into a protease-resistant, beta-sheet rich form (PrP(Sc)). Although the disease transmission normally requires direct interaction between exogenous PrP(Sc) and endogenous PrP(C), the pathogenic process in hereditary prion diseases appears to develop spontaneously (i.e. not requiring infection with exogenous PrP(Sc)). To gain insight into the molecular basis of hereditary spongiform encephalopathies, we have characterized the biophysical properties of the recombinant human prion protein variant containing the mutation (Phe(198) --> Ser) associated with familial Gerstmann-Straussler-Scheinker disease. Compared with the wild-type protein, the F198S variant shows a dramatically increased propensity to self-associate into beta-sheet-rich oligomers. In a guanidine HCl-containing buffer, the transition of the F198S variant from a normal alpha-helical conformation into an oligomeric beta-sheet structure is about 50 times faster than that of the wild-type protein. Importantly, in contrast to the wild-type PrP, the mutant protein undergoes a spontaneous conversion to oligomeric beta-sheet structure even in the absence of guanidine HCl or any other denaturants. In addition to beta-sheet structure, the oligomeric form of the protein is characterized by partial resistance to proteinase K digestion, affinity for amyloid-specific dye, thioflavine T, and fibrillar morphology. The increased propensity of the F198S variant to undergo a conversion to a PrP(Sc)-like form correlates with a markedly decreased thermodynamic stability of the native alpha-helical conformer of the mutant protein. This correlation supports the notion that partially unfolded intermediates may be involved in conformational conversion of the prion protein.
Concentration of choline acetylase in conducting tissue

In view of the recent information accumulated about the acetylating mechanism, choline acetylase activity has been redetermined in a few representative types of conducting tissue. This enzyme which specifically catalyzes the transfer of the acetyl group from acetyl-CoA to choline, is of great biological interest. Re-evaluation of its concentration under optimal experimental conditions, especially in the presence of a powerful activating system, appeared desirable. 1. 1. Extract from acetone-dried powder of guinea pig brain forms under optimal conditions 2.0–2.5 mg. acetylcholine/g./hr. The data are the same as reported previously without addition of the acetate activating enzyme system, thus indicating the presence of adequate amounts of the system in the preparation. 2. 2. In other tissues the concentrations expressed in milligrams acetylcholine formed/g./hr. were as follows: in peripheral nerve (rabbit sciatic) 1.3; in striated muscle (goldfish) 3.0–4.0; in electric tissue (Electrophorus electricus) 0.36; in heart muscle (rabbit) 0.015–0.040. The value for electric tissue was obtained with extracts of fresh tissue, in the other cases with extracts of acetone-dried powder. 3. 3. A more detailed study was made of the enzyme activity in dorsal and ventral roots in view of reports that dorsal roots do not contain choline acetylase and the sweeping conclusions based on the failure to find enzyme activity. The enzyme is present in both types of fibers. In dorsal roots 12–20 μg. of acetylcholine are formed/g. fresh tissue/hr. In ventral roots the enzyme concentration is extraordinarily high, 2 mg./g./ hr. in those of ox and 5 mg./g./hr. in those of dog. The latter figure is higher than that found with squid head ganglia which so far had the highest concentration of choline acetylase observed. 4. 4. The ratio of concentration of acetylcholinesterase over choline acetylase was found to be in most cases several hundred to a thousand or more. An exception is the ventral roots, where the ratio is 6. 5. 5. Some physiological implications are discussed.
ISSUES RELATING TO USE OF TRAVEL MODELS IN BENEFIT-COST ANALYSIS

Benefit-cost (B/C) analysis is a useful tool to compare the economic worth of transportation alternatives across modes. However, the application of tools such as MicroBENCOST, IDAS, and STEAM for B/C analysis in metropolitan areas raises several important technical issues that can significantly affect the results of the analysis. Several issues relate to use of four-step travel model outputs in estimation of benefits. Use of an inappropriate "No Build" base for comparison can exaggerate benefit estimates, as can a lack of consideration of the impact of induced travel. Link-level analysis can overestimate benefits from travel time savings, and at the system level, only trip-based analysis can adequately address issues relating to the "constant travel time budget" theory. Finally, use of congested speeds output by traffic assignment models can exaggerate travel time savings. These issues and their implications in metropolitan transportation decision making are discussed.
Differential effects of octylphenol, 17β-estradiol, endosulfan, or bisphenol A on the steroidogenic competence of cultured adult rat Leydig cells

Abstract In the current studies, we evaluated the effects of 4-tert-octylphenol (OP), endosulfan, bisphenol A (BPA), and 17β-estradiol on basal or hCG-stimulated testosterone formation by cultured Leydig cells from young adult male rats. Exposure of Leydig cells to increasing concentrations of OP (1 to 2000 nM), 17β-estradiol (1 to 1000 nM), endosulfan (1 to 1000 nM) or BPA (1 to 1000 nM), alone or with 10 mIU/mL hCG for 4 or 24 h, did not lower ambient testosterone levels, although cells exposed to higher OP concentrations + hCG for 24 h often had modest declines in testosterone (10 to 20%). Of interest, exposure to the highest concentration OP (2000 nM) alone for 4 or 24 h increased testosterone levels (∼ 2-fold in 4-h exposed cells). Whether prior exposure to OP + hCG for 24 h affects the subsequent conversion of steroid substrates to testosterone over 4 h was evaluated. Progressive declines in 1 μM 22(R) hydroxycholesterol, 1 μM pregnenolone, or 1 μM progesterone conversion to testosterone was observed beginning at 100 to 500 nM OP exposure (maximal declines of 40 to 12% of controls were observed); however, the conversion of 1 μM androstenedione to testosterone was not affected by OP. These results suggested that 24-h exposure to OP + hCG has no effect on 17β-hydroxysteroid dehydrogenase, which converts androstenedione to testosterone, but that it inhibits the 17α-hydroxylase/C17–20 lyase step, which converts progesterone to androstenedione. In addition, potentially, OP could inhibit cholesterol side/chain cleavage activity, which converts cholesterol to pregnenolone, and/or 3β-hydroxysteroid dehydrogenase, which converts pregnenolone to progesterone. Of interest, exposure to increasing concentrations of 17β-estradiol (1 to 1000 nM), endosulfan (1 to 1000 nM), or BPA (1 to 1000 nM) + hCG for 24 h had no effect on subsequent conversion of 22(R)hydroxycholesterol to testosterone. Furthermore, the inhibiting effects of OP + hCG exposure on subsequent conversion of progesterone to testosterone was unaffected by concomitant exposure to the pure estrogen antagonist, ICI 182,780, or the antioxidants, ascorbate or dimethyl sulfoxide, suggesting that the actions of OP are not mediated through binding to estrogen receptor α or β or by free radical induced damage to steroidogenic enzymes, respectively. These results demonstrate that direct exposure of adult Leydig cells to OP may have subtle effects on their ability to produce testosterone, which may not be detected by measuring ambient androgen levels. In addition, the effects of OP on Leydig cell testosterone formation appear to be different from those of the native estrogen, 17β-estradiol, and from other reported weak xenoestrogens such as endosulfan and BPA.
A Q-Method Analysis of Environmental Governance Discourses in Brazil's Northeastern Soy Frontier

This article describes and analyzes discourses regarding environmental governance held among key actors in a region of expanding high-input, high-output agriculture. Q-method, an intensive (small n) and quantitative technique in which n tests are measured by m individuals, was used to determine four empirically significant social perspectives: critical environmentalism, agri-environmentalism, private environmentalism, and statist environmentalism. The article highlights major differences and agreements among social perspectives, in addition to the arguments used to justify claims. These findings help fill a knowledge gap in the literature on governance debates between farmers and environmentalists; moreover, the findings contribute to a concern in the literature regarding the role of discourses in producing policy solutions to environmental governance problems. The article also supports continued use of Q-method in human geography, suggesting the value of Q as a research ends and means, particularly when ...
Human uterine decidual macrophages express renin

Human uterine decidual tissue contains many cell types, including stromal cells, fibroblasts, and macrophages. Earlier studies have shown that decidualized uterine stromal cells express renin, primarily in the form of prorenin. However, the possibility that decidual macrophages, which comprise about 30% of the cells in term decidua, also express renin has not been investigated. To determine whether macrophages express renin, macrophages were isolated from enzymatically dispersed term decidual cells using immunomagnetic beads coupled to antibodies to human leukocyte antigen (HLA)-DR, an antigen present on macrophages, but not other decidual cells. The isolated cells were 92.1% CD14 positive and contained the messenger ribonucleic acids (mRNA) for the interleukin-2 type alpha receptor, but not for PRL, a specific marker of decidualized stromal cells. Immunocytochemical studies of the macrophage-enriched fraction demonstrated that the macrophages contained renin, and reverse transcription-polymerase chain re...
A Developmental Framework for the Analysis of Premarital Dyadic Formation

A developmental framework for the analysis of premarital dyadic formation (PDF) is presented by the time-order interrelating of six pair processes, i.e., the achieving of similarity perception, pair rapport, self-disclosure, role-taking, role-fit, and dyadic crystallization. Empirical linkages between these pair processes are examined as underpinning for a conceptual framework from which developmental hypotheses may be generated and tested for the purpose of establishing construct validity for the PDF Framework.
Ceruloplasmin as an indicator of copper reserves in wild ruminants at high latitudes.

Northern ungulates must establish trace mineral reserves when forage is available in spring and summer to sustain biochemical activities through the long winter. Copper (Cu), zinc (Zn) and iron (Fe) reserves were measured in the serum, digestive tract, liver, and kidney of six male caribou and reindeer (Rangifer tarandus) fed a complete pelleted ration. Dry matter content and absolute amounts of Cu, Zn and Fe were highest in the liver. Digesta contents of Cu and Zn were greatest in the rumen but dry matter concentrations were greatest in the cecum reflecting the high levels of Cu and Zn in the diet. Serum ceruloplasmin (an oxidase containing Cu) activity was related to liver copper in captive reindeer and caribou (P < 0.05, r2 = 0.82) during spring and winter but not during the rut. Michaelis-Menten kinetics of ceruloplasmin were measured in sera from captive reindeer, muskox (Ovibos moschatus) and moose (Alces alces) (n = 3/species). Maximum velocities (VMAX) were 42, 20 and 9 (IU·L−1); kM were 0.38, 0.5...
CoREST: A functional corepressor required for regulation of neural-specific gene expression

Several genes encoding proteins critical to the neuronal phenotype, such as the brain type II sodium channel gene, are expressed to high levels only in neurons. This cell specificity is due, in part, to long-term repression in nonneural cells mediated by the repressor protein REST/NRSF (RE1 silencing transcription factor/neural-restrictive silencing factor). We show here that CoREST, a newly identified human protein, functions as a corepressor for REST. A single zinc finger motif in REST is required for CoREST interaction. Mutations of the motif that disrupt binding also abrogate repression. When fused to a Gal4 DNA-binding domain, CoREST functions as a repressor. CoREST is present in cell lines that express REST, and the proteins are found in the same immunocomplex. CoREST contains two SANT (SW13/ADA2/NCoR/TFIIIB B) domains, a structural feature of the nuclear receptor and silencing mediator for retinoid and thyroid human receptors (SMRT)-extended corepressors that mediate inducible repression by steroid hormone receptors. Together, REST and CoREST mediate repression of the type II sodium channel promoter in nonneural cells, and the REST/CoREST complex may mediate long-term repression essential to maintenance of cell identity.
The red queen in the corn: agricultural weeds as models of rapid adaptive evolution

Weeds are among the greatest pests of agriculture, causing billions of dollars in crop losses each year. As crop field management practices have changed over the past 12 000 years, weeds have adapted in turn to evade human removal. This evolutionary change can be startlingly rapid, making weeds an appealing system to study evolutionary processes that occur over short periods of time. An understanding of how weeds originate and adapt is needed for successful management; however, relatively little emphasis has been placed on genetically characterizing these systems. Here, we review the current literature on agricultural weed origins and their mechanisms of adaptation. Where possible, we have included examples that have been genetically well characterized. Evidence for three possible, non-mutually exclusive weed origins (from wild species, crop-wild hybrids or directly from crops) is discussed with respect to what is known about the microevolutionary signatures that result from these processes. We also discuss what is known about the genetic basis of adaptive traits in weeds and the range of genetic mechanisms that are responsible. With a better understanding of genetic mechanisms underlying adaptation in weedy species, we can address the more general process of adaptive evolution and what can be expected as we continue to apply selective pressures in agroecosystems around the world.
Retrograde Coronary Capillary Perfusion for Prevention and Reversal of Cardiogenic Shock in Experimental Myocardial Infarction

The coronary sinus and coronary veins offer an access route for delivery of increased oxygen to ischemic myocardium surrounding the central dead zone of heart muscle in cardiogenic shock due to myocardial infarction. This investigation was conducted to determine if transvenous retrograde coronary capillary perfusion with oxygenated blood would prevent and reverse cardiogenic shock in experimental myocardial infarction produced by acute ligation of the circumflex and anterior descending left coronary artery in dogs. Cardiac output and systemic blood pressure were maintained near control values for up to 30 minutes when total left coronary ligation was accompanied by coronary retroperfusion. Conversely, both cariac output and systemic blood pressure fell to severe cardiogenic shocks levels within 2 minutes of total left cardiogenic shock levels within 2 minutes of total left coronary artery occlusion without retrograde flow or when retrograde flow was terminated 5 to 30 minutes following simultaneous coronary ligation and institution of retrograde flow.