cssi/SciSciGPT-SciSciNet huggingface dataset:
Using Cultivated Microbial Communities To Dissect Microbiome Assembly: Challenges, Limitations, and the Path Ahead

As troves of microbiome sequencing data provide improved resolution of patterns of microbial diversity, new approaches are needed to understand what controls these patterns. Many microbial ecologists are using cultivated model microbial communities to address this challenge. These systems provide opportunities to identify drivers of microbiome assembly, but key challenges and limitations need to be carefully considered in their development, implementation, and interpretation. How well do model microbial communities mimic in vitro communities in terms of taxonomic diversity, trophic levels, intraspecific diversity, and the abiotic environment? What are the best ways to manipulate and measure inputs and outputs in model community experiments? In this perspective, I briefly address some of these challenges on the basis of our experience developing fermented food model communities. Future work integrating genetic and molecular approaches with cultivated model microbial communities will allow microbial ecology to develop a more mechanistic understanding of microbiome diversity.
Reconsidering our Graduation Efforts: The Economic Impact of Certificates, Associate’s, and Bachelor’s Degrees

ABSTRACTUnited States’ education policy efforts have focused on increasing college graduation rates, with an emphasis on bachelor’s degrees, with the expectation of greater economic prosperity. Mos...
Bourdieu in Latin America Through the Eyes of Néstor García Canclini

Nestor Garcia Canclini, in his consideration of Latin American culture and, especially, its artistic production, has bridged a sociological approach, emphasizing structural conditions of production, and an anthropological approach, considering the view from the perspective of the actors and agents involved in such processes. Pierre Bourdieu’s effort to straddle a similar span has long served as a pivotal point around and against which Garcia Canclini has developed his own theories about the functioning of Latin American cultural fields (art, cinema), institutions (museums, the state, non-profits, and private companies), actors (different publics, brokers, producers), and circuits (high, popular, middlebrow.) More generally, Bourdieu has been crucial to Canclini’s evolving thought on cultural production and consumption, and on their relations to culture in a Latin American national and globalized context.
A Comparison of Rate Expressions for the Low-Temperature Para-Orthohydrogen Shift

For purposes of either operational control of a reaction or reactor design, a mathematical expression relating the overall reaction rate to the composition of the fluid phase is essential. From the viewpoint of design or control, the fewer parameters in this expression, the better. Unfortunately, theory has not yet made sufficient progress that a priori calculation of these parameters is possible. Thus, at present, the principal use in the fields of control and design for these reaction-rate expressions is in interpolation and extrapolation of existing data. For extrapolation from one set of process conditions to another, the behavior of the parameters with changes in temperature and pressure should be known. The goal of this paper is to compare expressions which have been proposed for describing the low-temperature para-orthohydrogen shift reaction, to discuss the reliability of the expressions for different applications, and to consider the behavior with pressure and temperature of the parameters in these expressions.
Learning to Plan via Neural Exploration-Exploitation Trees.

Sampling-based algorithms such as RRT and its variants are powerful tools for path planning problems in high-dimensional continuous state and action spaces. While these algorithms perform systematic exploration of the state space, they do not fully exploit past planning experiences from similar environments. In this paper, we design a meta path planning algorithm, called \emph{Neural Exploration-Exploitation Trees} (NEXT), which can exploit past experience to drastically reduce the sample requirement for solving new path planning problems. More specifically, NEXT contains a novel neural architecture which can learn from experiences the dependency between task structures and promising path search directions. Then this learned prior is integrated with a UCB-type algorithm to achieve an online balance between \emph{exploration} and \emph{exploitation} when solving a new problem. Empirically, we show that NEXT can complete the planning tasks with very small searching trees and significantly outperforms previous state-of-the-arts on several benchmark problems.
Luck or Strategy? Some Insights Into Successful New Ventures

Utilizing Nobel Laureate, Daniel Kahneman's views on decision-making psychology and the general practice experience of Amazon's founder, Jeff Bezos, the authors formulate an approach to understand strategy and entrepreneurship. A hypothetical a priori probability model of a successful entrepreneurial venture is introduced in this paper. The model clarifies why the “prior to launch” probability of success is normally exceptionally low. But, low probability does not imply insignificance as free-market-driven new ventures with low probabilities of success can have a substantial impact on strategic planning within competitive firms. As a venture progresses through start-up phases and the probabilities of achieving individual critical single-events rise, the probability of venture success also increases as a function resembling the shape of a “hockey stick.” Entrepreneurially, the results show how a new venture's start-up can be quantitatively managed and analyzed with improved outcomes. The results provide some strategic insights on the difficulty of assessing competition as markets evolve.
Motor phenotype classification in moderate to advanced PD in BioFIND study

Abstract Background Three motor phenotypes have been described in PD: postural instability and gait difficulty (PIGD) dominant, tremor-dominant (TD), and indeterminate (IND) subtype. These phenotypes have been associated with different cognitive trajectories, motor outcomes, and biomarkers profiles. However, whether motor subtype classifications change with treatment and disease progression is not well established. Methods To evaluate motor subtype ratio changes, we used the chi-square test for the off and on state motor subtypes for 115 PD participants in the BioFIND study and used repeated-measures analyses to evaluate longitudinal changes in 162 PD participants with five-year follow-up in the PPMI study. Results PIGD and TD subtypes in moderate to advanced PD participants change with dopaminergic agents. For those who shifted subtypes, improvement in tremor accounted for the transition of 15 (25.4%) TD participants, while the lack of tremor improvement along with minimal changes in PIGD score resulted in changes for eight (19.0%) PIGD individuals. Analyses of PPMI data revealed that all three subgroups had a significant decrease in subtype ratio with disease progression and a significant decline in subtype ratio occurred only in the TD subgroup with dopaminergic agents. The impact of dopaminergic medication effect on subtype shift for each visit was also more notable with disease advancement. Conclusions Motor subtypes are not fixed but change with progression of the disease and with treatment. Improvement in tremor was the main contributor to motor phenotype transitions in the BioFIND cohort. A more stable classification system for subtypes based on underlying biological differences is desirable.
Do coffee cooperatives benefit farmers? An exploration of heterogeneous impact of coffee cooperative membership in Southwest Ethiopia

Smallholder farmers’ participation in agricultural cooperatives is often promoted as a promising strategy for overcoming market imperfections and to increase farmers’ productivity and income. In recognition of this potential, in recent years, Ethiopia has shown renewed interest in promoting cooperatives. However, there is lack of empirical evidence of the impact that cooperatives have on farmers’ performance in Ethiopia. Using a matching technique, we evaluate the impact of coffee cooperatives on the performance of their member households in terms of income and coffee production. We use data from coffee farmers in south-west Ethiopia. The overall results suggest that members of cooperatives are not faring much better than non-members. The treatment effects we measured were not statistically significant from zero. Yet, the aggregate figures mask differences between cooperatives and amongst individual cooperative members. Average treatment effects on members differ between cooperatives, in general older mem...
Gene Expression Meta-Analysis Reveals Concordance in Gene Activation, Pathway, and Cell-Type Enrichment in Dermatomyositis Target Tissues.

Author(s): Neely, Jessica; Rychkov, Dmitry; Paranjpe, Manish; Waterfield, Michael; Kim, Susan; Sirota, Marina | Abstract: ObjectiveWe conducted a comprehensive gene expression meta-analysis in dermatomyositis (DM) muscle and skin tissues to identify shared disease-relevant genes and pathways across tissues.MethodsSix publicly available data sets from DM muscle and two from skin were identified. Meta-analysis was performed by first processing data sets individually then cross-study normalization and merging creating tissue-specific gene expression matrices for subsequent analysis. Complementary single-gene and network analyses using Significance Analysis of Microarrays (SAM) and Weighted Gene Co-expression Network Analysis (WGCNA) were conducted to identify genes significantly associated with DM. Cell-type enrichment was performed using xCell.ResultsThere were 544 differentially expressed genes (FC ≥ 1.3, q l 0.05) in muscle and 300 in skin. There were 94 shared upregulated genes across tissues enriched in type I and II interferon (IFN) signaling and major histocompatibility complex (MHC) class I antigen-processing pathways. In a network analysis, we identified eight significant gene modules in muscle and seven in skin. The most highly correlated modules were enriched in pathways consistent with the single-gene analysis. Additional pathways uncovered by WGCNA included T-cell activation and T-cell receptor signaling. In the cell-type enrichment analysis, both tissues were highly enriched in activated dendritic cells and M1 macrophages.ConclusionThere is striking similarity in gene expression across DM target tissues with enrichment of type I and II IFN pathways, MHC class I antigen-processing, T-cell activation, and antigen-presenting cells. These results suggest IFN-γ may contribute to the global IFN signature in DM, and altered auto-antigen presentation through the class I MHC pathway may be important in disease pathogenesis.
Non-invasive Brain Delivery and Efficacy of BDNF in APP/PS1 Transgenic Mice as a Model of Alzheimer's Disease

Neurotrophic factors such as brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) have been demonstrated for their potential as a neuroregenerative treatment of Alzheimer’s disease (AD). Unfortunately, most proteins cannot be effectively delivered into the brain from the blood stream due to the presence of the blood-brain barrier (BBB). In this study, we delivered BDNF using ADTC5 as BBB modulator (BBBM) into the brains of a transgenic APP/PS1 mice, a mouse model for AD. As controls, two groups of APP/PS1 mice were treated with BDNF alone and vehicle, respectively. All three groups were subjected to behavioral/cognitive assessments in Y-maze and novel object recognition (NOR) tests as well as evaluation of the brain markers activated by BDNF. The results showed that BDNF + ADTC5 group performed significantly better in both the Y-maze and NOR assessments compared to mice that received BDNF alone or vehicle. In addition, significant upregulations of NG2 receptors as well as EGR1 and ARC mRNA transcripts were observed in the brain cortex of mice treated with BDNF+ADTC5, further indicating the efficacy of delivered BDNF in the brain. In addition, there were significant upregulation of NG2 glia cells as well as EGR1 and ARC mRNA transcripts in the brain cortex compared to controls, indicating the presence of delivered BDNF in the brain. There were high plaque loads in all mice groups, suggesting no influence of BDNF on the plaque formation. In summary, ADTC5 can deliver BDNF into the brains of APP/PS1 mice and the activity of BDNF in improving cognitive function was likely due to improvement in synaptic plasticity via NG2 glia cells and not by reducing the plaque load.
Black Food Geographies: Race, Self-Reliance, and Food Access in Washington, DC: by Ashanté M. Reese, Chapel Hill, University of North Carolina Press, 2019, 184 pp., ISBN 978-1-4696-5150-7

In Black Food Geographies: Race, Self-Reliance, and Food Access in Washington, DC, Ashante M. Reese has given us a profound and, also, accessible case study of resilience in the Deanwood neighborho...
Chief Executive Officer Succession and Board Decision Making: Review and Suggestions for Advancing Industrial and Organizational Psychology, Human Resources Management, and Organizational Behavior Research

We conduct a comprehensive review of the chief executive officer (CEO) succession literature and update a CEO succession typology that incorporated manuscripts published through 2014. Our review il...
Academic Entitlement in Physician Assistant Students.

PURPOSE The purpose of this study was to identify the prevalence and characteristics of academic entitlement (AE) among physician assistant (PA) students in the United States. METHODS A cross-sectional survey design was used to assess AE using 2 previously validated AE surveys. Current PA students were recruited via email, and survey data were analyzed using descriptive statistics and cumulative logistic regression. RESULTS Overall, the 337 PA students who participated in the study reported low levels of AE. Students displayed the highest level of AE on statements related to the role of professors and the lowest level of entitlement on statements pertaining to student responsibility and grade entitlement. Students who struggled academically were more likely to report AE in relation to professors' roles. Older students were more likely to display AE related to provision of necessary resources by the university and less likely to display AE regarding the method of delivery for learning materials. Higher levels of grade-related AE were found in students in the didactic phase, female students, and students who did not identify as White. In addition, students who did not identify as White were more likely to display AE in relation to tests. CONCLUSIONS Literature shows that AE has increased and is a major concern in higher education. Although the overall study results indicated relatively low AE, we found increased AE in certain student groups. Earlier identification of students at increased risk for AE would allow educators to intervene more effectively in a timely manner.
Molecular insights into malignant progression of atypical choroid plexus papilloma

Choroid plexus tumors are rare pediatric neoplasms ranging from low-grade papillomas to overtly malignant carcinomas. They are commonly associated with Li-Fraumeni syndrome and germline TP53 mutations. Choroid plexus carcinomas associated with Li-Fraumeni syndrome are less responsive to chemotherapy, and there is a need to avoid radiation therapy leading to poorer outcomes and survival. Malignant progression from choroid plexus papillomas to carcinomas is exceedingly rare with only a handful of cases reported, and the molecular mechanisms of this progression remain elusive. We report a case of malignant transformation of choroid plexus papilloma to carcinoma in a 7-yr-old male with a germline TP53 mutation in which we present an analysis of molecular changes that might have led to the progression based on the next-generation genetic sequencing of both the original choroid plexus papilloma and the subsequent choroid plexus carcinoma. Chromosomal aneuploidy was significant in both lesions with mostly gains present in the papilloma and additional significant losses in the carcinoma. The chromosomal loss that occurred, in particular loss of Chromosome 13, resulted in the losses of two critical tumor suppressor genes, RB1 and BRCA2, which might play a possible role in the observed malignant transformation.
Institutional Integrity and the Promise of Constitutionalism: Justice Moseneke, Judicial Authority and the Separation of Powers

This essay takes a demonstrative journey through Deputy Chief Justice Dikgang Moseneke’s Constitutional Court decisions, celebrating and illustrating the Justice’s personal and institutional commitment to the integrity of the Constitution. First, the author explores the scholarly arguments that see South African jurisprudence observing a unique ‘separation of powers’ doctrine, shaped by a distinctive constitutional system that falls somewhere between a common-law parliamentary system and the German system of constitutional democracy. Then the essay reflects on Justice Moseneke’s role in creating and upholding the separation of powers doctrine through an analysis of some of the Justice’s decisions. Finally, the essay explores Justice Moseneke’s role in establishing the parameters of the very judicial authority he practised, through a skilful exercise of institutional self-restraint and assertion of the role of integrity as well as the recognition of the Constitution’s creation of independent institutions outside of the traditional trias politica.
Boundary control for optimal mixing via Stokes flows and numerical implementation

This work develops scientific computing techniques to further the exploration of using boundary control alone to optimize mixing in Stokes flows. The theoretical foundation including mathematical model and the optimality conditions for solving the optimal control has been established by Hu and Wu in a series of work. The scalar being mixed is purely advected by the flow and the control is exerted tangentially on the domain boundary through the Navier slip conditions. The control design is motivated by the physical observations that the moving or rotating walls accelerate mixing. A gradient descent-based optimization algorithm is designed. A critical problem is the computation of the Gateaux derivative or the gradient of the cost functional. Two methods are proposed: one is based on the Variational Formula (VF) and one utilizes Algorithmic Differentiation (AD). The convergence of the algorithm is studied and various designs of boundary control using cosine and sine functions with time segmentation are computed. The algorithm has a first order convergence rate and the VF method is more efficient by taking only one third of the time as the AD method when the dimension of control basis is large. The numerical implementations show that the boundary control produces similar mixing results as internal mixings in the existing literature. The mixing effect becomes better when more diverse basis control functions and more time segmentation are utilized. It is shown that the mixing decay rate in time follows power rules, approximately. The numerical study in this work suggests that boundary control alone could be an effective strategy for mixing in incompressible fluid flows.
With or Without the Self? Arguments in Favor of the Hindu Concept of the Atman over the Buddhist Understanding of the Anatman

As found in the Upanishads, readers come to encounter many ideas regarding the “Self” as opposed to the “self,” or the Atman versus the atman. Now, complicating matters further readers encounter the antithetical concept, of the Atman and atman, or the Buddhists understanding of the anatman as found in the Dhammapada. First, this piece will unpack the idea of both the “Self” and the “self,” or the Atman and the atman, as understood in Hindu philosophy and theology. Next, this essay will then describe the Buddhists understanding of anatman, or the absence, or emptiness of the self, or the nullification of the self, or the atman as well as even of the Self, or the Atman. Finally, this piece will resolve by arguing in favor of the Self, or the Atman as well as the self, or atman over the Buddha’s notion of the anatman.
Staged Reconstruction for HLHS

As noted in earlier chapters, the term hypoplastic left heart syndrome (HLHS) has been used to describe a group of various cardiac malformations consisting of hypoplasia or absence of the left ventricle and hypoplasia of the ascending aorta. In the most extreme form of HLHS, valvar aortic atresia is present in association with a very tiny ascending aorta and diminutive left ventricle. Similar to other single ventricle malformations, hypoplastic left heart syndrome is characterized by a circulation dependent upon patency of the ductus arteriosus with obligatory mixing of pulmonary and systemic venous blood. The single ventricle (in this case an anatomic right ventricle) supplies the pulmonary circulation by way of the branch pulmonary arteries and the systemic circulation by way of a patent ductus arteriosus. Flow in the ascending aorta is generally retrograde and, in patients with aortic atresia, the ascending aorta acts as a common coronary artery supplying coronary perfusion.
Regulation of alternative splicing by RNA editing

The enzyme ADAR2 is a double-stranded RNA-specific adenosine deaminase which is involved in the editing of mammalian messenger RNAs by the site-specific conversion of adenosine to inosine. Here we identify several rat ADAR2 mRNAs produced as a result of two distinct alternative splicing events. One such splicing event uses a proximal 3' acceptor site, adding 47 nucleotides to the ADAR2 coding region, changing the predicted reading frame of the mature ADAR2 transcript. Nucleotide-sequence analysis of ADAR2 genomic DNA revealed the presence of adenosine-adenosine (AA) and adenosine-guanosine (AG) dinucleotides at these proximal and distal alternative 3' acceptor sites, respectively. Use of the proximal 3' acceptor depends upon the ability of ADAR2 to edit its own pre-mRNA, converting the intronic AA to an adenosine-inosine (AI) dinucleotide which effectively mimics the highly conserved AG sequence normally found at 3' splice junctions. Our observations indicate that RNA editing can serve as a mechanism for regulating alternative splicing and they suggest a novel strategy by which ADAR2 can modulate its own expression.
Reflections on Visual Field Research

This article describes ongoing visual field research by focusing on its self-reflective and auto-ethnographic components. Photographs and field notes are presented and personal encounters from the field are described. Recognizing the symbiotic order of the personal and political, the author details confrontations and emotions from ongoing efforts at recording visually.
A 26-Bit Absolute Encoder System

In October, 1985, new encoder readout electronics were installed on the MMT to read the existing absolute encoders. With the new electronics, the angular resolution of the encoder system has been increased from 24 bits (0.077 arcseconds) to 26 bits (0.019 arcseconds) and the amplitudes of the raw uncorrected errors related to the period of the InductosynsTM* have been reduced from a few arcseconds to the order of +/- 0.5 arcseconds or better.
OMNI-SHRIMP: An interpretive language which mimics OMNITAB

A description of OMNITAB, an interpretive language, is provided along with a discussion of its use. The major attributes of SHRIMP (ah interactive mathematical package developed at the University of Texas) are pointed out in detail and its use and relationship to OMNITAB defined. An example is included to show SHRIMP compatibility with OMNITAB.
Sodium Perxenate and Xenon (II) Difluoride Reduction at the Dropping-Mercury Electrode.

Sodium perxenate in alkaline solutions is reduced in a single step to xenon at the dropping-mercury electrode. The half-wave potential for perxenate changes from -0.21 to -0.31 volts against a Hg2SO4-Hg reference electrode in the pH range 10.1 to 11.3. Xenon (II) difluoride in acidic solution is reduced in a single step to xenon, at the potential of approximately zero against the Hg2SO4-Hg reference electrode. The reduction wave is followed by a broad maximum which can be effectively suppressed by fluoride ion. The diffusion current varies in linear fashion with concentration.
Transitions à plusieurs quanta et amplification maser dans les systèmes à deux niveaux

Tout systeme justiciable de la mecanique quantique qui peut devenir le siege de transitions radiatives entre deux niveaux d'energie peut donner lieu a des transitions a plusieurs quanta si, en plus, l'un au moins des deux niveaux d'energie possede un moment dipolaire electrique ou magnetique de valeur moyenne finie. On peut tirer parti de cet effet pour produire une emission induite de puissance hertzienne avec une distribution de population normale de temperature absolue positive. Ce processus est analogue a une diffusion Raman coherente ou deux quanta electromagnetiques interviennent dans la transition, l'un des photons etant absorbe, l'autre etant emis. C'est ainsi qu'on peut obtenir une emission stimulee a une frequence ω par un systeme a deux niveaux de separation energetique ħ ω0 en appliquant au systeme un champ de rayonnement de frequence ω' = ω0 + ω, ω' etant ainsi superieur a ω0. Si la puissance appliquee a la frequence ω' est distribuee sur un intervalle de frequence plus large que la largeur naturelle des niveaux, cette distribution de frequence determine la largeur et la forme de la radiation emise ω. Le cas particulier d'un systeme de spin 1/2 sera traite en detail pour obtenir les expressions de la susceptibilite induite a la frequence d'amplification ω et pour discuter le facteur de bruit du a l'emission spontanee. On discute l'application a l'effet maser dans des ferrites, dans molecules et dans d'autres systemes physiques. Cet effet peut aussi etre utilise en spectroscopie en vue d'etudier en detail la forme de raie d'une transition optique en induisant une transition multiple de ce type par application simultanee d'une frequence optique et d'une frequence hertzienne.
Controlled transitions between cupolets of chaotic systems

We present an efficient control scheme that stabilizes the unstable periodic orbits of a chaotic system. The resulting orbits are known as cupolets and collectively provide an important skeleton for the dynamical system. Cupolets exhibit the interesting property that a given sequence of controls will uniquely identify a cupolet, regardless of the system's initial state. This makes it possible to transition between cupolets, and thus unstable periodic orbits, simply by switching control sequences. We demonstrate that although these transitions require minimal controls, they may also involve significant chaotic transients unless carefully controlled. As a result, we present an effective technique that relies on Dijkstra's shortest path algorithm from algebraic graph theory to minimize the transients and also to induce certainty into the control of nonlinear systems, effectively providing an efficient algorithm for the steering and targeting of chaotic systems.
Role of a selective aldosterone blocker in mice with chronic heart failure.

Abstract Background Spironolactone, a nonselective aldosterone blocker, has a cardioprotective effect; however, significant endocrine side effects limit its use. Eplerenone is a new selective aldosterone blocker. We investigated whether eplerenone attenuates cardiac remodeling and improves function in a mouse model of heart failure and whether coadministration of eplerenone and an angiotensin-converting enzyme inhibitor (ACEi) provides better cardioprotection than either agent alone. Methods and results C57BL/6J mice were subjected to myocardial infarction (MI) by ligating the left anterior descending coronary artery. Two weeks later, the mice were either left untreated or treated with (1) eplerenone, (2) ACEi, or (3) eplerenone plus ACEi for 12 weeks. Systolic blood pressure (SBP) was measured and echocardiography performed before MI and weekly thereafter. At the end of the study, interstitial collagen fraction (ICF) and myocyte cross-sectional area (MCSA) were examined histologically. We found that (1) eplerenone significantly improved ejection fraction and cardiac output and decreased left ventricular (LV) systolic area, LV weight, ICF, and MCSA independently of changes in SBP compared with untreated animals; (2) ACEi had similar beneficial effects, accompanied by a significant reduction in SBP; and (3) combined treatment offered limited additional benefit beyond monotherapy. Conclusions In mice with MI, eplerenone attenuates progression of heart failure comparably to ACEi, and its effect is independent of BP lowering.
Implantable Cardioverter Defibrillator Storm: Nursing Care Issues for Patients and Families

Implantable cardioverter defibrillators (ICDs) are being used for primary and secondary prevention of life-threatening cardiac arrhythmias, and evidence suggests that increased use is likely in the future. ICD storm, the delivery of two or more shocks within 24 hours, occurs in 10% to 20% of patients who have ICDs and can have long-lasting psychological and physical consequences. An understanding of the factors associated with ICD storm, relevant assessment, and patient and family teaching and counseling can help clinicians to better meet the needs of patients who have experienced ICD storm.
Effects of finite probe intensity on degenerate frequency mixing in saturable amplifiers

Abstract Phase conjugation by degenerate frequency mixing (DFM) in saturable amplifiers, including the effects of pump depletion, a non-zero incident probe wave intensity and saturated gain of all waves in the nonlinear medium, is analyzed numerically. Plane wave DFM reflectivities greater than unity are predicted, even in the presence of pump depletion, for sufficiently large amplifier gains. At a given level of incident probe-wave intensity the DFM reflectivity approaches its weak probe-wave value at sufficiently large incident pump intensities, but deviates from these values at lower pump intensities. Conditions are established under which the DFM reflectivity is effectively independent of the incident probe-wave intensity even when the incident pump intensity is smaller than that of the incident probe wave. Under these conditions the system holds the potential for faithful conjugation using pump waves that are considerably weaker than the probe waves being conjugated. The results also predict that under certain conditions, the intensity of the backward-generated wave can be larger than either the incident probe wave or the incident pump wave.
Magnetic resonance cholangiography

Magnetic resonance cholangiography (MRC) can be performed with data from a routine imaging protocol, without the need for additional pulse sequences or special equipment. We studied three patients with obstructive jaundice who underwent magnetic resonance imaging (MRI) of the liver. T2-weighted fat suppressed fast spin-echo sequences were processed with a maximum intensity projection algorithm to create three-di-mensional images of the dilated portions of the biliary tree. Results were correlated with endoscopic retrograde cholangiopancreatography and computed tomography. These images compare favorably with those acquired on scanners in which special breath-holding gradient echo protocols are used.
Urban America : growth, crisis, and rebirth

List of Tables Preface Introduction Part I. Urban America in 1950 1. Urban Areas of the Northeast 2. Urban Areas of the Sunbelt before Air Conditioning 3. An American Dilemma in 1950 Part II. Urban Growth and Prosperity: 1950-1970 4. The Industrial Northeast and the Great Migration 5. The New Sunbelt Takes Off 6. Suburbanization: 1950-1970 7. Signs of Trouble Ahead 8. August 1965 Part III. The Years of Urban Crisis: 1970-1990 9. The Great Society and the Urban Riots 10. Urban Employment Trends in the Northeast 11. Urban Growth in the Sunbelt: 1970-1990 12. New Urban Scholarship 13. The Vicious Circle in Urban America Part IV. The Rebirth of Urban America after 1990 14. Rebirth in America's Cities 15. Urban Rebirth in the Northeast: 1990-2000 16. Urban Growth and Rebirth in the Sunbelt 17. Trends after 2000: What Is Next for Urban America? Bibliography Index About the Author.
Relative Efficacy of Biologic Specimens and Interviews in Detection of Prenatal Cocaine Use † 1145

Few studies have investigated the relative ability of different biologic specimens to identify fetal cocaine exposure. As part of a federally funded, prospective study, we identified subjects through chart review of all patients admitted to Labor and Delivery. Experienced interviewers enrolled all consenting patients with history of prenatal cocaine use and the next admission with no recorded use. Extensive interviews postpartum: 1). verified history of use; 2). helped eliminate women with chronic illnesses and medications, other illicit drug use, >1.5 oz of absolute alcohol per day; and 3). detailed amount, frequency and timing of drug use. Amniotic fluid, cord blood, infant urine and meconium, and maternal hair were collected using specific protocols. Analysis of biologic samples was performed blindly using immunoassay verified by gas chromatography/mass spectrometry. Of 65 subjects whose specimens have been analyzed to date, 45 had one or more biologic specimens positive for cocaine metabolites or admitted prenatal use: 33 were identified by interview, 26 by meconium, 21 (of 38 analyzed) by hair, 21 by urine, 16 (of 42) by cord blood, and 9 (of 25) by amniotic fluid. The best combination of two methods, interview and meconium identified, 39 (87%) of the 45; interview, meconium and hair together identified all but 7%. Of the 73% identified by interview, 9 admitted only first trimester use and 9 admitted use in each trimester. As hypothesized, urine and meconium were generally not positive for admitted early use. However, hair analysis did detect over 70% of those admitting first trimester use, but, disappointingly, only identified about half of those positive by another method. No one biologic specimen identified all the users detected by other methods. The single method that maximumly identified users was detailed history taken by experienced interviewers. Further analyses will compare type and quantity of metabolites detected in maternal versus infant specimens within each trimester.
Proposed Bunching Scheme for a Polarized H- Injector

Improvements to the polarized H/sup -/ injector at LAMPF will include a two-stage buncher and beam chopper. The buncher scheme will permit the compression of a major part of the current in 20 rf cycles of the drift-tube linac (100 nsec) into a single rf cycle (5 nsec), thus making possible time-of-flight experiments with the polarized H/sup -/ beam. A proposed first buncher stage would use a ramp drive waveform; the second stage, a sinusoidal waveform. Design and sensitivity calculations are summarized, including beam energy considerations, buncher and chopper drive requirements, and longitudinal and transverse beam dynamics. The calculations indicate that about 70% of the beam from the source may be bunched in the 1-nsec acceptance region of the linac, with less than 0.1% of the beam in neighboring rf cycles. 5 figs.
Pharmacological modulation of stress-induced behavioral changes in the light/dark exploration test in male C57BL/6J mice

Psychological stress is a major risk factor for mood and anxiety disorders. However, the phenotypic manifestation of stress effects varies across individuals, likely due, in part, to genetic variation. Modeling the behavioral and neural consequences of stress across genetically diverse inbred mouse strains is a valuable approach to studying gene × stress interactions. Recent work has shown that C57BL/6J mice exposed to ten daily sessions of restraint stress exhibited increased exploration of the aversive light compartment in the light/dark exploration (LDE) test. Here we sought to clarify the nature of this stress-induced phenotype by testing the ability of treatment with various clinically efficacious drugs of different therapeutic classes to rescue it. Ten days of restraint increased light compartment exploration, reduced body weight and sensitized the corticosterone response to swim stress. Subchronic administration (during stress and LDE testing) of fluoxetine, and to a lesser extent, lithium chloride, rescued stress-induced LDE behavior. Chronic fluoxetine treatment prior to (plus during stress and testing) failed to block the LDE stress effect. Acute administration of antipsychotic haloperidol, anti-ADHD medication methylphenidate or anxiolytic drug chlordiazepoxide, prior to LDE testing, was also unable to normalize the LDE stress effect. Collectively, these data demonstrate a treatment-selective prophylactic rescue of a restraint stress-induced behavioral abnormality in the C57BL/6J inbred strain. Further work with this novel model could help elucidate genetic and neural mechanisms mediating stress-induced changes in mouse 'emotion-relevant' behaviors and, ultimately, further understanding of the pathophysiology of stress-related neuropsychiatric disorders. This article is part of a Special Issue entitled 'Anxiety and Depression'.
Ultrasonic imaging in scanning electron microscopy

A new type of microscopy is described here which uses a focused, modulated electron beam to generate ultrasonic waves at the front surface of a specimen and a piezoelectric transducer to detect these waves at the rear surface. The transducer output is used to form a scanned, magnified image of the specimen. A unique feature of this technique is that image contrast comes primarily from spatial variations in thermal and elastic properties. Images of integrated circuits have been obtained with ∼4 µm resolution. In thin film specimens 0.1 µm resolution should be possible.
Cervical LEEP margin status and post‐LEEP Pap smear follow‐up

This retrospective study examined the relationship between loop electrosurgical excision procedure (LEEP) margin status and post-LEEP Pap smear results. LEEP is an established modality for the diagnosis and treatment of cervical intraepithelial neoplasia. LEEP has advantages over destructive and ablative techniques because excised tissue is examined histologically to determine the grade and extent of intraepithelial neoplasia. Though the status of ectocervical and endocervical margins is routinely reported for LEEP operations, controversy exists about the significance of positive margins for the prediction of recurrent disease. We examined the relationship between LEEP margin status and abnormalities on post-LEEP Pap smears. Previously published studies have reported mixed results about the value of positive margin status [1–4]. The study consisted of 129 consecutive female patients undergoing LEEP procedures. Follow-up Pap smear data were available for 106 women. Clinicians with knowledge of margin status performed the Pap smears using cytobrushes. Margin status was determined using all margin information available in reports. Submitted LEEP specimens contained one or more pieces. Additional specimens were sometimes submitted and determined to supercede the margins on the main specimen. Among the 106 patients with post-LEEP follow-up Pap smears, 27.5% were positive for abnormal squamous cells (atypical cells of undetermined significance [ASCUS] and above) at their first satisfactory post-LEEP Pap smear. A significantly higher proportion of first post-LEEP Pap smear results were positive in women with positive ectocervical ⁎ Corresponding author. 2853 Sunset View, Signal Hill, California 90755, USA. Tel.: +1 562 986 1217. E-mail address: Lynn.sandweiss@gmail.com (L. Sandweiss).
A ParE-ParC fusion protein is a functional topoisomerase.

Type II topoisomerases are responsible for DNA unlinking during DNA replication and chromosome segregation. Although eukaryotic enzymes are homodimers and prokaryotic enzymes are heterotetramers, b...
Volumetric assessment of tumor infiltration of adjacent white matter based on anatomic MRI and diffusion tensor tractography.

Rationale and Objectives To perform a retrospective, quantitative assessment of the anatomic relationship between intra-axial, supratentorial, primary brain tumors, and adjacent white matter fiber tracts based on anatomic and diffusion tensor magnetic resonance imaging (MRI). We hypothesized that white matter infiltration may be common among different types of tumor. Material and Methods Preoperative, anatomic (T1- and T2-weighted), and LINESCAN diffusion tensor MRI were obtained in 12 patients harboring supratentorial gliomas (World Health Organization [WHO] Grades II and III). The two imaging modalities were rigidly registered. The tumors were manually segmented from the T1- and T2-weighted MRI, and their volume calculated. A three-dimensional tractography was performed in each case. A second segmentation and volume measurement was performed on the tumor regions intersecting adjacent white matter fiber tracts. Statistical methods included summary statistics to examine the fraction of tumor volume infiltrating adjacent white matter. Results There were five patients with low-grade oligodendroglioma (WHO Grade II), one with low-grade mixed oligoastrocytoma (WHO Grade II), one with ganglioglioma, two with low-grade astrocytoma (WHO Grade II), and three with anaplastic astrocytoma (WHO Grade III). We identified white matter tracts infiltrated by tumor in all 12 cases. The median tumor volume (± standard deviation) in our patient population was 42.5 ± 28.9 mL. The median tumor volume (± standard deviation) infiltrating white matter fiber tracts was 5.2 ± 9.9 mL. The median percentage of tumor volume infiltrating white matter fiber tracts was 21.4% ± 9.7%. Conclusions The information provided by diffusion tensor imaging combined with anatomic MRI might be useful for neurosurgical planning and intraoperative guidance. Our results confirm previous reports that extensive white matter infiltration by primary brain tumors is a common occurrence. However, prospective, large population studies are required to definitively clarify this issue, and how infiltration relates to histologic tumor type, tumor size, and location.
Superconducting augmented rail gun (SARG)

Superconducting augmentation consists of a superconducting coil operating in the persistent mode closely coupled magnetically with a normally conducting rail gun. A theoretical investigation of the effect of this system on a rail gun has shown that two benefits occur. Projectile velocities and launch efficiencies increase significantly depending on the magnetic coupling between the rail and augmentation circuits. The previous work [1] evaluated an idealized system by neglecting energy dissipation effects. In this paper, we extend the analysis to include the neglected terms and show improved actual launch efficiencies for the SARG configuration. To evaluate this concept, a one meter, 0.95 cm square bore rail gun powered by a 5 KV, 1440 µf capacitor discharging into a pulse shaping inductance of about 5µh was constructed. This system will accelerate a 4 g armature type projectile to the 0.8 km/sec range. Superconducting augmentation will be accomplished using a 4 Tesla dipole magnet recently acquired from DOE's Lawrence Berkeley Laboratory. This magnet system, originally designed as an ESCAR bending magnet, has been modified to a warm bore configuration operating in either the persistent or constant current mode powered by 1600 amp DC supplies. These modifications will allow the above rail gun to be inserted and tested in the SARG configuration. Several factors, including magnetic quench protection, reproducibility of results, relatively low magnetic coupling coefficients, minimazation of rail wear, etc., indicated that this experimental evaluation be conducted with an armature device. An advanced armature design is incorporated in our projectiles. In this paper, we will discuss these details in more depth and present preliminary results of rail gun performance.
Optical illumination and critical dimension analysis using the through-focus focus metric method

In this paper we present recent developments in optical microscope image analysis using both, best focus optical image as well as those images conventionally considered out of focus for metrology applications. Depending on the type of analysis, considerable information can be deduced with the additional use of the out of focus optical images. One method for analyzing the complete set of images is to calculate the total "edge slope" from an image, as the target is moved through-focus. A plot of the sum of the mean square slope is defined as the through-focus focus metric. We present a unique method for evaluating the angular illumination homogeneity in an optical microscope (with Koehler illumination configuration), based on the through-focus focus metric approach. Both theoretical simulations and experimental results are presented to demonstrate this approach. We present a second application based on the through-focus focus metric method for evaluating critical dimensions (CD) with demonstrated nanometer sensitivity for both experimental and optical simulations. An additional approach to analyzing the complete set of images is to assemble or align the through focus image intensity profiles such that the x-axis represents the position on the target, the y-axis represents the focus (or defocus) position of the target with respect to the lens and the z-axis represents the image intensity. This two-dimensional image is referred to as the through focus image map. Using recent simulation results we apply the through focus image map to CD and overlay analysis and demonstrate nanometer sensitivity in the theoretical results.
Renal thrombosis with infarction in the newborn; two different forms.

SUMMARY A previously healthy female infant which has had a difficult forceps delivery is on the fifth day of life taken ill with shock, abdominal distension, a mass at the site of the right kidney, and macroscopic hematuria. Nephrectomy is carried out, on vital indication and on the suspicion of hemorrhage from a right-sided renal tumor. A total renal infarction is found, as well as a thrombus, reaching from the renal vein up into vena. cava. The patient made a rapid recovery.
Pulse centroid velocity of the Poynting vector.

The evolution of the pulse centroid velocity of the Poynting vector for both ultrawideband rectangular and ultrashort Gaussian envelope pulses is presented as a function of the propagation distance in a dispersive, absorptive dielectric material. The index of refraction of the material is described by the Lorentz–Lorenz formula in which a single-resonance Lorentz model is used to describe the mean molecular polarizability. The results show that, as the propagation distance increases above a value that is on the order of an absorption depth at the pulse carrier frequency, the centroid velocity of an ultrawideband/ultrashort pulse tends toward the rate at which the Brillouin precursor travels through the medium. For small propagation distances when the carrier frequency of the optical pulse lies in the absorption band of the material, the centroid velocity can take on superluminal and negative values.