cssi/SciSciGPT-SciSciNet huggingface dataset:
Mechanical Properties and Adhesion of PZT Thin Films for MEMS

Piezoelectric films are attractive materials for use in microelectromechanical systems (MEMS) due to their ability to act as both sensors and actuators. One of the primary modes of deformation is the deflection of lead zirconate titantate (PZT) beams and membranes, where the adhesion of the film is critical for the reliability of the device. Thin films of PZT between 250 and 750 nm have been grown via solution deposition routes onto platinized silicon substrates. The films have been tested using nanoindentation techniques. Two failure mechanism in these films have been observed Indentation induced delamination at the PZT-Pt interface occurs after the indenter tip is removed from the film when loads between 1 and 10 mN are applied to the sample, and at large loads (glt;75 mN) failure can be generated between the underlying oxide film and the silicon substrate while the tip is still engaged with the sample. Since each of these failure modes has a different mechanics solution, the results are compared to determine adhesion energy of the films. Fracture around the delaminated regions has been examined using scanning probe and electron microscopy. Freestanding PZT membranes above micromachined cavities have been mechanically deformed to examine the mechanical response and failure modes in these structures. The adhesion of the PZT improves with increased percent crystallization due to the introduction of residual tensile stresses. Processing, mechanical properties, and failure modes in these devices will be discussed.
Dust Particle Trajectories in Aircraft Radial Turbines

This paper presents the results of analytical and experimental studies of the trajectories that atmospheric dust particles follow as they move through a radial turbine. A dimensionless parameter is derived which can be used during preliminary design analysis to indicate the sizes of particles that will be most damaging to the turbine. The study reveals several internal surfaces that will be more severely eroded because most particles entering the turbine will strike them. A moderate amount of erosion can be expected near the end of the scroll and on the last few nozzle passages near the end of the scroll. All particles greater that 42/t will strike these surfaces. A severe erosion problem occurs on the nozzle trailing edges, because particles greater than 2-3fi will not penetrate the rotor. These particles are pushed outward by centrifugal forces where they bounce off the nozzle trailing edges. Particles greater than 1\\i have enough inertia to overcome the centrifugal force and these particles enter the rotor. After striking the rotor with a perpendicular impact, they also travel outward to the nozzle trailing edges.
Cytokinin-dependent specification of the functional megaspore in the Arabidopsis female gametophyte

The life cycle of higher plants alternates between the diploid sporophytic and the haploid gametophytic phases. In angiosperms, male and female gametophytes develop within the sporophyte. During female gametophyte (FG) development, a single archesporial cell enlarges and differentiates into a megaspore mother cell, which then undergoes meiosis to give rise to four megaspores. In most species of higher plants, including Arabidopsis thaliana, the megaspore closest to the chalaza develops into the functional megaspore (FM), and the remaining three megaspores degenerate. Here, we examined the role of cytokinin signaling in FG development. We characterized the FG phenotype in three triple mutants harboring non-overlapping T-DNA insertions in cytokinin AHK receptors. We demonstrate that even the strongest mutant is not a complete null for the cytokinin receptors. Only the strongest mutant displayed a near fully penetrant disruption of FG development, and the weakest triple ahk mutant had only a modest FG phenotype. This suggests that cytokinin signaling is essential for FG development, but that only a low threshold of signaling activity is required for this function. Furthermore, we demonstrate that there is elevated cytokinin signaling localized in the chalaza of the ovule, which is enhanced by the asymmetric localization of cytokinin biosynthetic machinery and receptors. We show that an FM-specific marker is absent in the multiple ahk ovules, suggesting that disruption of cytokinin signaling elements in Arabidopsis blocks the FM specification. Together, this study reveals a chalazal-localized sporophytic cytokinin signal that plays an important role in FM specification in FG development.
Interaction of electromagnetic wave with elastic wave in elastic media

In this paper study the interaction of EM wave with elastic wave for piezoelectric-like elastic media. Although the problem was investigated earlier, the used approaches were based on the PDE form of governing equations. We develop an integral equation method to solve the problem with arbitrary 3D geometries, and the solution process can then take all advantages of integral equation solvers. We will consider the influence of elastic wave on the EM wave in the future, so that the fully coupled integral equations can be derived.
The effect of crowding on access and quality in an academic ED

Background Emergency department crowding has the potential to cause undesirable outcomes. We evaluated ED access and provider and patient assessments of quality. Methods This multimethod study, done in an urban academic ED, included descriptive analysis of administrative records, paired physician and nurse provider surveys, and pre- or postpatient surveys regarding expectations and experiences. Our outcomes were rates and characteristics of patients who left without being seen (LWBS), provider ratings of crowding/compromised care, and patient satisfaction. Results During data collection periods, 11 743 patients registered, and 9% LWBS. Patients who LWBS tended to be younger than 45 years (relative risk [RR] = 1.7; 95% confidence interval [CI], 1.5-1.9), of nonurgent/stable triage acuity (RR = 3.1; 95% CI, 2.5-3.8), and without insurance (RR = 1.5; 95% CI, 1.3-1.7). Seventy-four percent of all patients had insurance, and 28% were private. Doctors and nurses had 81% agreement (κ = 0.54) in their assessment of crowded conditions, which were temporally associated with LWBS rates (P Conclusions We find that ED crowding increased LWBS rates and patient satisfaction. Systemwide changes in ED organization will be necessary for the ED to fulfill its role as a safety net provider and meet public health needs during disaster surge capacity.
Oxidative modifications produced in HL-60 cells on exposure to benzene metabolites

We have studied the effects of the benzene metabolites hydroquinone, p-benzoquinone or 1,2,4-benzenetriol on cytotoxicity, active oxygen formation, hydrogen peroxide (i.e. hydroperoxide) production and nitric oxide formation in HL-60 cells. We also examined the effects of these compounds on antioxidant enzymes and intracellular antioxidants in these cells. The cytotoxicity of benzene metabolites to HL-60 cells was found to be of the order of p-benzoquinone>hydroquinone>benzenetriol. No appreciable changes in the basal levels of either superoxide anion production or nitric oxide formation were observed following exposures to the benzene metabolites, but significant increases in superoxide were seen on stimulation with TPA for each metabolite, whereas hydroquinone and p-benzoquinone, but not 1,2,4-benzenetriol, increased nitric oxide production under these conditions. Following exposure to the benzene metabolites, HL-60 cells showed significant rises in hydrogen peroxide formation compared to controls. The study of antioxidant enzymes and intracellular antioxidants suggested that the benzene metabolites inhibit or reduce the levels of different antioxidant mechanisms and, thereby, cause the accumulation of free radicals in these cells predisposing them for oxidative damage.
Two-year toxicity and carcinogenicity studies of ampicillin trihydrate and penicillin VK in rodents

Toxicology and carcinogenesis studies of ampicillin trihydrate and penicillin VK, two widely used β-lactam antibiotics, were performed in F344/N rats and B6C3F1 mice. In these studies ampicillin trihydrate was administered for 2 years to rats at doses of 0.750, or 150 mg/kg and to mice at doses of 0, 1500, or 3000 mg/kg, and penicillin VK was administered to rats and mice at doses of 0, 500, or 1000 mg/kg. Both drugs were administered by oral gavage in corn oil. Toxic lesions of the stomach were seen in rats and mice after ampicillin trihydrate administration and in mice after penicillin VK administration. In male rats that received ampicillin trihydrate there was a marginal increase in incidence of mononuclear cell leukemia and pheochromocytomas of the adrenal gland medulla. There was no evidence for carcinogenic activity in female rats or male and female mice after ampicillin trihydrate administration or in rats and mice after penicillin VK administration.
Comparison between vestibular and subcutaneous insertion of deslorelin implants for oestrus induction in bitches.

Contents Investigations using sustained-release deslorelin implants at various insertion sites have shown that this method consistently induces oestrus in anoestus bitches. However, fertility comparisons between implant insertion sites have not been performed. Anestrous beagle bitches received one 2.1 mg deslorelin implant beneath the vestibular mucosa (VM group; n = 6) or in the subcutaneous tissue between the shoulder blades (SubQ group; n = 8). Vestibular implants were removed when serum progesterone concentrations first exceeded 1.5 ng/ml. Vaginal cytologies and blood samples were collected daily and bitches were inseminated during oestrus. Serum progesterone and deslorelin concentrations were measured and pregnancy status was determined using ultrasonography. There were no differences between groups in the intervals between implant administration and the onset of proestrus, the time of the luteinizing hormone surge and the onset of cytologic diestrus. There were also no differences in the number of corpora lutea or foetuses. However, conception rate was significantly lower in the SubQ group. The pregnancy rate did not differ significantly between the VM and SubQ groups [4 out of 6 (66.7%) and 3 out of 8 (37.5%), respectively]. One bitch (16.7%) in the VM group and three bitches (37.5%) in the SubQ group suffered distinct, premature declines in serum progesterone concentrations starting 1–4 weeks after cytologic diestrus. Serum progesterone concentrations did not recover (premature luteal failure), resulting in abortion. Bitches with premature luteal failure in the SubQ group still had serum deslorelin concentrations >100 pg/ml 20 days after implant insertion, suggesting a possible association between prolonged deslorelin release and luteal failure.
Whose Politics? Reflections on Clarence Stone’s Regime Politics

Stone’s retrospective article holds to the view of his earlier work that a city’s fundamental capacity to confront existential challenges is made possible only by the engagement of elite actors with the resources for sustained politics. In this article, we set out to illustrate ways in which actors marginal to regime politics—neighborhood organizations, nonprofits, labor movements, and immigrant groups—can offer examples of sustained politics that provide alternate agendas for city politics by looking at three different policy arenas in three different cities: housing in New York, labor rights in Los Angeles, and education in Detroit.
A Retrospective Survey of Endocardial Proliferative Lesions in Rats

Sixty, proliferative, endocardial lesions were diagnosed in 19,304 rats, for an overall incidence of 0.3%. This population consisted of 10,127 Fischer 344, 8,737 Wistar, 200 Sprague-Dawley, and 240 Long Evans rats from chronic/oncogenicity studies reported at Lilly Research Laboratories from 1976 to 1988. Of the 60 proliferative lesions, 44 were classified as endocardial hyperplasia, 15 as endocardial schwannomas, and one as an endocardial sarcoma for prevalence rates of 0.2%, 0.08%, and 0.005%, respectively. Affected rats ranged in age from 42 to 110 weeks. There were no sex or treatment-related differences in the prevalence of the rat endocardial proliferative lesions. A review of endocardial lesions in 18 of 233 Wistar rats treated with carbamate derivatives revealed endocardial hyperplasia in 12 rats, schwannomas in five rats, and a sarcoma in one rat. One of the 12 rats with endocardial hyperplasia also had an intramural schwannoma. Of 200 Wistar rats given N-nitroso-N-methylurea, two had endocardial hyperplasia, and one had an endocardial schwannoma. Mor- phologic features were similar in either spontaneous or treatment-associated hyperplasia or neoplasia of the rat endocardium. Probable Schwann cell origin of the endocardial proliferative lesions was indicated by positive immunohistochemical staining for S- 100 antigen in 101 12 spontaneous and 1 111 4 carcinogen-associated en- docardial hyperplastic lesions. Further, 1 5/ 1 6 spontaneous and 617 carcinogen-associated neoplasms were im- munoreactive to S- 100. No tumor metastasis was recorded in either the spontaneously affected or carcinogen- treated rats. Key wards: Endocardial proliferative lesions; mesenchymal hyperplasia; neoplasia; schwannoma; sarcoma; rat. neurinoma, neurilemmoma and neuro~arcoma,~~,~~ Anitschkow cell sarc0ma,3~.~6 undifferentiated sarcoma,I6 fibromatous pr~liferation,'~.~' endomyocardial disea~e,~~~~~ endo- myocardial fibrosis,29 endocardial thi~kening,~~ and en- docardial mesenchymal tumor.2' 15.45.49 This report deals with the prevalence of spontaneous proliferative endocardial lesions in four strains of rats used in chronic/oncogenicity studies during a 12-year period. A comparison of selected lesions by morpho- logic and immunocytochemical means, as well as a review of experimentally-induced lesions are present- ed.
Simulation of Flight Dynamics with an Improved Post-Stall Aerodynamics Model

A recently developed post-stall aerodynamics prediction method has been improved for use in real-time simulation of aircraft flight dynamics. The aerodynamic prediction method models the boundary layer separation due to stall using an effective decambering on each wing section. The aerodynamics of the configuration is rapidly calculated using superposition of stored lift distributions, which allows the the method to be used in real-time flight simulation even for post-stall conditions. For a given aircraft state vector, the method predicts forces and moments on the configuration. This aerodynamics method is coupled with flight-dynamics equations of motion (EOM) such that the complete aerodynamics is solved at each time step of the solution of the flight EOM. At the current stage, the approach does not handle the effects of bodies, propeller-wash, and wake interference. These are to be incorporated in follow-on work.
Understanding Sound Sensitivity in Individuals with Autism Spectrum Disorders

Literature on sound sensitivity in individuals with and without autism spectrum disorders (ASD) is reviewed in this article. Empirical evidence is examined, and physiologic and psychoemotional-behavioral perspectives are described.There is virtually no evidence of true physiological differences in auditory systems of individuals with ASD. It is evident, however, that many people with ASD (a) feel fearful and anxious about sound, and (b) may experience unpleasant physiological sensations because of autonomic and/or behavioral responses to nonpreferred sounds, but (c) can learn to react in less stigmatizing, more effectively self-regulating ways. Current assessment and intervention practices are discussed, and a case is presented. Heightened understanding of this issue among caregivers and interventionists may ultimately improve life participation for individuals with ASD.
Educating for quality: quality improvement as an activity of daily learning to improve educational and patient outcomes.

THE QUALITY OF care delivered to children is suboptimal, with opportunities for improving quality and value across care settings and conditions. Leading health care organizations have recognized that quality improvement (QI) should play a vital role in improving the quality of care delivered to all populations, including children. For this strategy to succeed, all health professionals, including physicians, should become proficient in QI. Recognizing the need for widespread and dramatic improvements in health care delivery systems, the American Board of Pediatrics (ABP) designed their program of Maintenance of Certification to include that all diplomates must at a minimum be active participants in critically analyzing and improving the care of the patients they care for. Most recently, the Accreditation Council for GraduateMedical Education (ACGME) developed specific milestones for competencies related to QI and instituted the Clinical Learning Environment Review (CLER) Program to help identify and disseminate best practices on how residents and fellows can become better engaged in institutional safety and QI to enhance their training while simultaneously improving care for the patient populations they care for. What is the state of QI education in pediatric graduate medical education?Mann et al conducted a survey to better understand the perspective of pediatric residency program directors. In recent years, an increasing proportion of program directors report providing education in QI, and that curricula typically include several elements conducive to learning QI, including an experiential component. Program directors reported a variety of process improvement methodologies as the basis of their curriculum. However, only a minority of resident QI projects had support for project management. As institutional resources become more constrained, it will become even more challenging to support QI in areas that are exciting to trainees but are not aligned with institutional priority areas. Only a minority of program directors reported being satisfied with their QI curricula.
Dislocation Density Based Crystal Plasticity Finite Element Simulation of Alpha-Iron

Ferritic/martensitic steels such as HT9 steel, is used for structural components in nuclear power plants because of its high strength and good swelling resistance. Understanding the mechanical behavior of these steels is quite important, since it will affect the strength and the life of the component. In this study, a dislocation density based crystal plasticity finite element model is developed in which different types of dislocation evolves on the activated 12 slip systems in alpha-iron. The dislocation evolves in the form of closed loop and the dislocation density is tracked as internal state variable, the generation and annihilation of dislocations are modeled based on the dislocation interaction laws. The plastic flow is calculated based on the dislocation densities and a generalized Taylor equation is used as the hardening law, and the hardening is assumed to be isotropic in this study. The evolution of polycrystal texture of alpha-iron is presented in the form of pole figures, which indicate the orientation spread and agree with the experimental result. The model also indicates the inhomogeneous dislocation distribution and stress concentration at the grain boundaries.
Improved Acetic Acid Resistance in Saccharomyces cerevisiae by Overexpression of the WHI2 Gene Identified through Inverse Metabolic Engineering

Development of acetic acid-resistant Saccharomyces cerevisiae is important for economically viable production of biofuels from lignocellulosic biomass, but the goal remains a critical challenge due to limited information on effective genetic perturbation targets for improving acetic acid resistance in the yeast. This study employed a genomic-library-based inverse metabolic engineering approach to successfully identify a novel gene target, WHI2 (encoding a cytoplasmatic globular scaffold protein), which elicited improved acetic acid resistance in S. cerevisiae. Overexpression of WHI2 significantly improved glucose and/or xylose fermentation under acetic acid stress in engineered yeast. The WHI2-overexpressing strain had 5-times-higher specific ethanol productivity than the control in glucose fermentation with acetic acid. Analysis of the expression of WHI2 gene products (including protein and transcript) determined that acetic acid induced endogenous expression of Whi2 in S. cerevisiae. Meanwhile, the whi2Δ mutant strain had substantially higher susceptibility to acetic acid than the wild type, suggesting the important role of Whi2 in the acetic acid response in S. cerevisiae. Additionally, overexpression of WHI2 and of a cognate phosphatase gene, PSR1, had a synergistic effect in improving acetic acid resistance, suggesting that Whi2 might function in combination with Psr1 to elicit the acetic acid resistance mechanism. These results improve our understanding of the yeast response to acetic acid stress and provide a new strategy to breed acetic acid-resistant yeast strains for renewable biofuel production.
Oxidation and Reduction of Bi2Sr1.85Cuo6-Y Crystals

The effects of oxidizing and reducing atmospheres on the oxygen contents and electrical properties of Bi2Sr1.85CuO6-y single crystals were investigated. As-grown crystals were normally semiconducting but became metallic and superconducting after heating the crystals for several hours in oxygen at temperatures between 500 and 800°C Previously superconducting crystals were made semiconducting by heat treatments in helium at temperatures between 700 and 780°C. Changes in the oxygen content of the crystals as well as the oxidation and reduction kinetics during the various heat treatments were monitored using standard thermogravimetric techniques. A good correlation was found between the annealing temperatures in oxygen (helium) at which there was an uptake (loss) of oxygen by the crystals, 500°C (700°C), and the onset (loss) of metallic behavior and superconductivity. From isothermal measurents of the weight change as a function of time, it was found that the apparent activation energies for oxidation and reduction were about 0.5 eV and 2.7 eV, respectively. A partial decomposition of the crystals during the various heat treatments, however, precluded a quantitative analysis of the kinetic data.
Systemic and coronary hemodynamic effects of hexadylamine.

Summary1. Systemic and coronary hemodynamics have been determined in a series of 10 intact anesthetized mongrel dogs by the Fick principle and nitrous oxide method respectively, before and during a constant intravenous infusion of hexadylamine (MRL 38, dicyclohexyl-piperidyl-ethylene hydrochloride). 2. Administration of hexadylamine produced peripheral and coronary vasodilatation, as well as increased cardiac output and coronary blood flow. 3. The coronary sinus oxygen content increased significantly, with narrowing of the myocardial arteriovenous oxygen difference. 4. Left ventricular work and myocardial oxygen consumption increased slightly but insignificantly.
LRC Coronary Prevention Trial: Baltimore

Intense, initial efforts tu enroll 250 individuals in the Coronary Prevention Trial at Johns Hopkins University Hospital through referrals from private physicians and from commercial laboratories were largely unsuccessful. Not until a mass-screening effort was initiated in the community were we able to contact sufficient numbers of potential study candidates. The time needed to acquire the trial candidates was 2.5 times as long as our original estimate, and 35,000 individuals were tested in the process.
Surveillance and PFGE analysis on Vibrio parahaemolyticus in agricultural products in Minhang

Objective:To investigate the contamjnatjon status and correlative biological characteristics of VP in agricultural products in Minhang district,and doing drug resistance,to offer date for establishing early-warning systm of food poisoning caused by VP.Methods:The VP was isolated from agricultural products according to GB/T4789.7-2008,and that identified by biochemical test;Virulence genes about tdh and trh were examined by PCR;Analyzed the molecular subtying by PFGE,and adopting software-BioNumerics to do the clustering;K-B method was used to do the drug resistance.Results:The38 strains without tdh and trh were isolated from 373 samples,the positive rate was 10.2%;There were 38 distractive PFGE patterns,and showed completely different;Most strains showed resistance to ampicillin,amoxycillin/clavulanic acid,The resistance rate to ampiciIlin was 92.1%,All the strains showed sensitivity to ciprofloxacin,levofloxacin,gentamicin,amikacin,trimethoprim,chloramphenicol,tetracycline and cephalosporins.Conclusion:The cross-contamination Of VP in agricultural products in Minhang was rather severe,the homology of certain strains showed low similary;the drug-resistant strains were existence in agricultural products.
Macrophage Activation by Cross‐Linked Dextran

Cross-linked dextran (Sephadex) has been reported as an effective inducer of peritoneal exudates resulting in a large yield of macrophages after injection into mice, and macrophages obtained in this manner have been used for a variety of studies. We examined the possibility that cross-linked dextran not only induces peritoneal exudate but functions also as a macrophage activator. Following confirmation of a markedly increased yield of macrophages in Balb/c mice injected with preswollen Sephadex G-25 beads, glass adherence and migration in agarose of these macrophages were compared with the activities of cells isolated following the injection of saline, thioglycollate, or complete Freund's adjuvant (CFA). Dextran administration resulted in a significant increase in these activities in relation to saline and thioglycollate injections, and resembled CFA in the magnitude of its effect. Dextran-induced macrophages were then examined for activation as defined by nonspecific antitumor activity. Cells of a transplantable fibrosarcoma line and a urethane-induced primary lung adenoma served as targets. As compared with macrophages isolated from saline-injected mice, cells induced by Sephadex showed an approximately fivefold and twofold increase in activity against adenoma and fibrosarcoma targets, respectively. To examine the ability of Sephadex to induce macrophage antitumor activity in vitro, peritoneal macrophages were cultured in the presence of the dextran for 24 hours and tested against adenoma targets. The tumoricidal/static activity of such macrophages was significantly increased relative to controls and was nearly identical to the activity of macrophages induced by Sephadex in vivo. It is clear that cross-linked dextran in the form of Sephadex G-25 can function both as an inducer of peritoneal exudate and as an effective macrophage activator with regard to the activation criteria studied.
Case 34: Unprofessional Behavior

You have participated in a clinical study. Your role has been very active, as you have helped produce the protocol and the consent form and got it passed by the IRB. You made data sheets and collected some of the patient’s data. You even helped write up the paper. However when the paper is finally published, you discover that your name is not on it.
Best performing definition of accelerated knee osteoarthritis: data from the Osteoarthritis Initiative.

Background:We evaluated agreement among several definitions of accelerated knee osteoarthritis (AKOA) and construct validity by comparing their individual associations with injury, age, obesity, an...
Trends in the Incidence of Fatal Prostate Cancer in the United States by Race

Abstract Background Prostate-specific antigen (PSA) testing has dramatically changed the composition of prostate cancer (PCa), making it difficult to interpret incidence trends. New methods are needed to examine temporal trends in the incidence of clinically significant PCa and whether trends vary by race. Objective To conduct an in-depth analysis of incidence trends in clinically significant PCa, defined as cases in which PCa was the underlying cause of death within 10 yr of diagnosis. Design, setting, and participants We extracted incident PCa cases during the period 1975–2002 and associated causes of death and survival through 2012 from nine cancer registries in the population-based Surveillance Epidemiology and End Results program database. Outcome measurements and statistical analysis We applied joinpoint regression analysis to identify when significant changes in trends occurred and age–period–cohort models to examine longitudinal and cross-sectional trends in the incidence of fatal PCa. Results and limitations Among 51 680 fatal PCa cases, incidence increased 1% per year prior to 1992, declined 15% per year from 1992 to 1995, and further declined by 5% per year through 2002. Age-specific incidence rates of fatal disease decreased >2% per year among men aged ≥60 yr, yet rates remained relatively stable among men aged ≤55 yr. Fatal disease rates were >2-fold higher in black men compared with white men, a racial disparity that increased to 4.2-fold among younger men. Conclusions The incidence of fatal PCa substantially declined after widespread PSA screening and treatment advances. Nevertheless, rates of fatal disease among younger men have remained relatively stable, suggesting the need for additional attention to early onset PCa, especially among black men. The persistent black-to-white racial disparity observed in fatal PCa underscores the need for greater understanding of the causes of this difference so that strategies can be implemented to eliminate racial disparities. Patient summary We assessed how the incidence of ultimately fatal prostate cancer (PCa) changed over time. We found that the incidence of fatal PCa declined by >50% since the introduction of prostate-specific antigen testing and advances in treatment options; however, incidence rates among younger men remained relatively stable, and younger black men exhibited a 4.2-fold higher risk for fatal disease compared with white men.
Board conflict and public performance on urban and non-urban boards: Evidence from a national sample of school board members

In this article a national sample of survey data collected from U.S. school board members paired with school-district level data from the National Center for Education Statistics are used to test the relationships between board conflict and school district performance. We add to the existing governance literature through our use of a national data set and specific focus on the impact of conflict on urban school boards. The analysis indicates a negative relationship between board conflict and district performance that is magnified on urban school boards. We conclude that school board members in general can improve school district performance by mitigating potential sources of board conflict, and that the importance of reducing conflict is greater on urban school boards.
An in-process laser localized pre-deposition heating approach to inter-layer bond strengthening in extrusion based polymer additive manufacturing

Abstract Material extrusion-based 3D printing processes have shown importance in the overall development of the field of additive manufacturing and displayed tremendous potential to becoming a cross-cutting tool for research, engineering, developmental work in a wide array of disciplines. In the context of the Fused Deposition Modeling (FDM, one form of Materials extrusion-based 3D printing), one of the main process issues lies in the property anisotropy of parts built using this method, even with process optimization. To address this issue, we report a near-IR laser-based pre-deposition heating method to locally heat up the region of an existing layer near the nozzle before an extrudate comes in contact with the heated region. This in-process approach raises the inter-layer interface temperature to above the critical temperature to increase the interpenetrating diffusion, and therefore the inter-layer bond strength. A 50% increase in the inter-layer bond strength in parts built with this approach is demonstrated. The in-process pre-deposition local heating approach reported here represents an effective means to increase the inter-layer bond strength, and property isotropy of FDM parts. Further, this approach is capable of real-time monitoring and controlling of temperatures at the inter-layer and inter-filament interfaces across the entire volume of a built part, allowing control of the physics of the FDM process to achieve desired mechanical properties.
Case study: fishing for information on the Internet

As the Internet continues to grow, the amount of accessible information becomes increasingly vast. Search tools exist that allow users to find relevant information. However, a search can often produce such a large amount of data that it becomes hard to ferret out the most appropriate and highest quality information. In addition, some search tools lose valuable information when displaying the results to the user. The paper describes a search visualization tool, called FISH, for viewing hierarchically structured information and managing information overload. FISH (Forager for the Information Super Highway) allows users to visualize the results of search requests across large document spaces in a way that preserves the structure of the information space. FISH displays the returned documents as rectangles, using a combination of order, indentation, size, and color to denote document hierarchy, the score of the documents with respect to the search, and other data attributes. In addition, the user can navigate through the document space for in-depth probing and refinement.
Democracy and minority language recognition: tyranny of the majority and the conditional effects of group size

ABSTRACTWhat explains minority language recognition? Why are some governments more responsive than others to minority linguistic demands? While there are reasons to believe democracies – as protectors of civil liberties – are generally more likely to recognize minority demands, I argue only those without a sizable majority extend such recognition to the highest levels. This is because the dominance of one large linguistic group electorally impedes a democratic government’s ability to grant such benefits to the smaller ones. I test this argument by using a newly constructed measure of minority language recognition. This variable identifies whether a minority language is used in public education, and if so, it differentiates between instruction of and instruction in a minority language. I find that while democracies are indeed more likely to acknowledge minority languages, the effects are conditional: only those without a majority are able or willing to accommodate minorities to the fullest extent. Otherwis...
The Bible in Music: A Dictionary of Songs, Works, and More

The book is a dictionary of 274 pages of entries of music titles and topics. It also includes bibliography, indices, and a chronology.
EZH1 in germ cells safeguards the function of PRC2 during spermatogenesis

We previously reported the requirement of Polycomb Repressive Complex 2 (PRC2) for spermatogenesis through transcriptional repression of somatic genes and meiosis-specific genes. To characterize how PRC2's two methyltransferase subunits, EZH1 and EZH2, regulate histone H3 lysine 27 (H3K27) methylation during germ cell development, we generated mouse models with a germline ablation of EZH1 and/or EHZ2. Only the combined loss of EZH1 and EZH2 caused a depletion of global H3K27me3 marks and meiotic arrest in spermatocytes. Genome-wide analysis of H3K27me3 in spermatogenic cells revealed that a noncanonical EZH1-PRC2 could establish and maintain this histone mark on somatic genes and certain meiotic genes. Consistent with it having active enhancers in testis, Ezh1 was not only abundant in highly differentiated spermatocytes but also in actively proliferating progenitor and stem germ cells. Taken together, our findings suggest that the expression level of Ezh1 determines the restoration of H3K27 methylation in the absence of the canonical EZH2-PRC2.
Oesophageal cancer: RNA editing of SLC22A3 mRNAs: causative relevance to familial ESCC?

A new study reveals an involvement of SLC22A3 in the development of familial oesophageal squamous cell carcinoma (ESCC). Reduced expression of SLC22A3 is detected not only in ESCC tumours but also in non-tumour tissues of patients with familial ESCC. Interestingly, adenosine-to-inosine editing of SLC22A3 mRNA is proposed to drive early tumour invasion and metastasis, by inhibiting SLC22A3 expression.
Mitral Valve-in-Valve Implantation as an Elective or Rescue Procedure in High-Risk Patients

Background Transapical transcatheter mitral valve-in-valve implantation (TA-MVIVI) for bioprosthetic valve failure is an emerging alternative to reoperation in high-risk patients. We report our outcomes in a patient population with a high proportion of cardiogenic shock. Methods Retrospective review was performed of all patients undergoing TA-MVIVI with an Edwards Sapien (Edwards Life sciences, Irvine, CA) prosthesis at our center between the years 2013 and 2017. Results Nineteen patients with bioprosthetic mitral valve failure were included (mean age 78 ± 12 years). All patients were New York Heart Association functional class III or greater; The Society of Thoracic Surgeons mean score was 22.0 ± 17.5. The TA-MVIVI was performed in the setting of cardiogenic shock in 12 of 19 patients (63%). The primary mechanism for valve failure was regurgitation in 58%, stenosis in 21%, and mixed in 21%. All patients underwent successful TA-MVIVI with no deaths, strokes, or myocardial infarctions at 30 days. Two patients had brief postprocedural cardiac arrest but had full recovery. Mean transmitral gradient decreased from 12 ± 5 mm Hg to 5 ± 3 mm Hg ( p = 0.0005). There was 1 death from unknown causes within the first year (5.2%). At a mean follow-up of 339 days (range, 30 to 1291), trace transvalvular regurgitation had developed in 3 of 19 patients (15.8%). There was no paravalvular regurgitation. At last follow-up, 89.5% of patients were New York Heart Association class I or II. Conclusions Transapical transcatheter mitral valve-in-valve implantation can safely be performed in a patient population with a high proportion of cardiogenic shock with favorable clinical outcomes.
Early pubertal timing and adult adjustment outcomes: Persistence, attenuation, or accentuation?

Abstract Early pubertal timing is associated with internalizing and externalizing problems during adolescence. However, few studies explicitly test whether early puberty is especially problematic for those with pre-existing problems (i.e., accentuation) and little is known about whether the negative correlates of early pubertal timing persist past young adulthood. We address these questions using longitudinal data from up to 451 participants in the Iowa Youth and Families project (e.g., Ge, Conger, & Elder, 1996, 2001). We replicated and extended previous results reported for this sample during adolescence (e.g., early maturing boys and girls reported more substance use) and found some evidence for accentuation in adolescence for psychological distress and substance use. However, correlations between early puberty and adult outcomes assessed up to two decades later were largely indistinguishable from zero including attenuation effects. These results suggest that any negative correlates of early pubertal timing are attenuated by the fourth decade of life.
On the rates of Type Ia supernovae originating from white dwarf collisions in quadruple star systems

We consider the evolution of stellar hierarchical quadruple systems in the 2+2 (two binaries orbiting each other's barycentre) and 3+1 (triple orbited by a fourth star) configurations. In our simulations, we take into account the effects of secular dynamical evolution, stellar evolution, tidal evolution and encounters with passing stars. We focus on type Ia supernovae (SNe Ia) driven by collisions of carbon-oxygen (CO) white dwarfs (WDs). Such collisions can arise from several channels: (1) collisions due to extremely high eccentricities induced by secular evolution, (2) collisions following a dynamical instability of the system, and (3) collisions driven by semisecular evolution. The systems considered here have initially wide inner orbits, with initial semilatus recti larger than 12 AU, implying no interaction if the orbits were isolated. However, taking into account dynamical evolution, we find that $\approx 0.4$ ($\approx 0.6$) of 2+2 (3+1) systems interact. In particular, Roche Lobe overflow can be triggered possibly in highly eccentric orbits, dynamical instability can ensue due to mass-loss-driven orbital expansion or secular evolution, or a semisecular regime can be entered. We compute the delay-time distributions (DTDs) of collision-induced SNe Ia, and find that they are flatter compared to the observed DTD. Moreover, our combined SNe Ia rates are $(3.7\pm0.7) \times 10^{-6} \,\mathrm{M}_\odot^{-1}$ and $(1.3\pm0.2) \times 10^{-6} \,\mathrm{M}_\odot^{-1}$ for 2+2 and 3+1 systems, respectively, three orders of magnitude lower compared to the observed rate, of order $10^{-3} \, \mathrm{M}_\odot^{-1}$. The low rates can be ascribed to interactions before the stars evolve to CO WDs. However, our results are lower limits given that we considered a subset of quadruple systems.
A versatile expression vector for the growth and amplification of unmodified phage display polypeptides.

Abstract Proteins and polypeptides represent nature's most complex and versatile polymer. They provide complicated shapes, diverse chemical functionalities, and tightly regulated and controlled sizes. Several disease states are related to the misfolding or overproduction of polypeptides and yet polypeptides are present in several therapeutic molecules. In addition to biological roles; short chain polypeptides have been shown to interact with and drive the bio-inspired synthesis or modification of inorganic materials. This paper outlines the development of a versatile cloning vector which allows for the expression of a short polypeptide by controlling the incorporation of a desired DNA coding insert. As a demonstration of the efficacy of the expression system, a solid binding polypeptide identified from M13 phage display was expressed and purified. The solid binding polypeptide was expressed as a soluble 6xHis-SUMO tagged construct. Expression was performed in E. coli using auto-induction followed by Ni-NTA affinity chromatography and ULP1 protease cleavage. Methodology demonstrates the production of greater than 8 mg of purified polypeptide per liter of E. coli culture. Isotopic labeling of the peptide is also demonstrated. The versatility of the designed cloning vector, use of the 6xHis-SUMO solubility partner, bacterial expression in auto-inducing media and the purification methodology make this expressionun vector a readily scalable and user-friendly system for the creation of desired peptide domains.
SOME RESULTS FROM A-SPACES

Publisher Summary This chapter presents some results from A-spaces. A space Y is an A-space if whenever (A ) is a decreasing sequence of subsets of Y with a common accumulation point y in Y, then there exist Bn ⊂ An such that un Bn is not closed. If one requires the sets An to be open, then Y is called an outer-open A-space. If one requires y to belong to the closure of un Bn but not to un Bn, then Y is called a strict A-space. The following properties of a regular space Y of nonmeasurable cardinality are equivalent.: (1) Y is a strict A-space and (2) every hereditarily quotient map onto Y is countably bi-quotient. The following properties of a regular space Y of arbitrary cardinality are equivalent: (1) Y is countably bi-sequential and (2) Y is both a Frechet space and an A-space.
Cultural Aspects of Becoming Technologically Literate

About three or four years ago, my then teenage son called with great excitement to say that he and a friend had just finished navigating the most incredible corn maze! That telephone call, which today might likely have been a short text message, came at two o’clock in the morning and was totally out of context and disruptive to my sound sleep.
Of Bacteria, Scientists, and Women: Ramón y Cajal’s “El pesimista corregido”

Written in the final years of the nineteenth century and published in 1905, Santiago Ramon y Cajal’s Cuentos de vacaciones provide wide-ranging reflections on the cultural import of science and the social ramifications of new scientific discoveries. “El pesimista corregido,” the story discussed in this article, mixes the conventions of nineteenth-century realism with science fiction as it explores the possible pitfalls of a slavish commitment to scientific instruments that promise miraculously enhanced vision—in the story’s case, the microscope. Influenced by Lorraine Daston’s notion of “the moral economy of science,” Comparone delves into an aspect of this story that has been ignored until now: the role of gender and gender relations in the context of scientific hubris. Taking into account the epistemic ramifications of magnification, this article examines the narrator’s view of gender, marriage and fatherhood, claiming that these views are difficult to dissentangle from the author’s view of scientific objectivity. As Comparone notes, Ramon y Cajal, himself a Nobel Prize Winner in Physiology, has a surprisingly ambivalent view of his obsessive scientist protagonist. The article further argues that a preoccupation with aesthetics plays a role in the story’s treatment of the issues raised when science becomes so infatuated, or horrified, with the cellular level that it loses sight of the living organism.
One read per cell per gene is optimal for single-cell RNA-Seq

An underlying question for virtually all single-cell RNA sequencing experiments is how to allocate the limited sequencing budget: deep sequencing of a few cells or shallow sequencing of many cells? A mathematical framework reveals that, for estimating many important gene properties, the optimal allocation is to sequence at the depth of one read per cell per gene. Interestingly, the corresponding optimal estimator is not the widely-used plug-in estimator but one developed via empirical Bayes.
Cancer survivors' experiences with breakdowns in patient-centered communication.

OBJECTIVE This study analyzed cancer survivors' communication experiences that fell short of being patient-centered. Patients' descriptions of communication "breakdowns" were analyzed according to domain (eg, information exchange, fostering relationships, and managing emotions), whether it was a breakdown of commission (what was communicated) or omission (what should have been communicated) and whether it involved a clinician or the health care organization. METHODS Cancer survivors (from an online panel of patients) completed the Patients Assessment of Communication Experience measure. Ratings less than "excellent" elicited a prompt asking where communication fell short. Communication breakdowns were categorized as one of commission/omission, if it involved a clinician/health care system, and within which communication domain. Thematic analysis explored how communication breakdowns affected respondents' cancer care experiences. RESULTS Overall communication was rated as less than excellent by 153 respondents, of which 79 identified a specific communication breakdown. Over half (n = 43, 54%) were problems of omission, mostly attributed to interaction with health care organizations (n = 25). Breakdowns of commission (n = 36, 46%) occurred primarily within clinical encounters (n = 32). Most breakdowns were problems of information exchange (49%) or fostering relationships (27%). Three overarching themes emerged-emotional fallout from unmet information needs, inattention to patient perspective, and uncertainty about navigation and team communication. CONCLUSIONS Patient-centered communication breakdowns create distress that worsens patients' cancer care experiences. Communication skills training for clinicians should address listening, perspective taking, and assessing/satisfying patients' information and emotional needs. Health care organizations should enhance processes to provide timely, useful information to patients.
Entrepreneurship and Innovation at MIT: Continuing Global Growth and Impact—An Updated Report

Entrepreneurship and Innovation at MIT: Continuing Global Growth and Impact—An Updated Report