cssi/SciSciGPT-SciSciNet huggingface dataset:
The contribution of root systems to plant nutrient acquisition

Abstract Essential nutrients for plant growth and survival are acquired from a heterogeneous soil environment. As the only part of the plant in direct contact with the soil, roots are solely responsible for nutrient uptake and assimilation. In this chapter we review the current state of knowledge about root system structural features that maximize the acquisition of nitrogen and phosphorus.
Description of Histopona breviemboli sp. n. from the Balkan Peninsula (Arachnida, Araneae, Agelenidae)

Histopona breviemboli sp. nov. (male) is described and illustrated from Bulgaria where it was collected in beech forest habitats (Strandzha Mts). The new species has somatic characters that correspond well to those of the genus Histopona . However, its embolus is much shorter than in any other Histopona species and the radix is also very different, having a thorn-like shape. The species cannot be placed with certainty in any of the existing Histopona species-groups.
keybin: Key-Based Binning for Distributed Clustering

Traditional machine learning algorithms often require computations on centralized data, but modern datasets are collected and stored in a distributed way. In addition to the cost of moving data to centralized locations, increasing concerns about privacy and security warrant distributed approaches. We propose keybin, a distributed key-based binning clustering algorithm for high-dimensional spaces. keybin locally generates a spatial key for each data point across all dimensions without needing knowledge of other data. Then, it performs a conceptual Map- Reduce procedure in the index space to form a global clustering assignment. We present an implementation and a case study on the capabilities and limitations of this approach, showing that this algorithm can learn a global clustering structure with limited communication and can scale with the dimensionality and size of data sets.
The Effect of Mandatory Access Prescription Drug Monitoring Programs on Foster Care Admissions

The opioid epidemic is a national public health emergency. As the number of fa- tal overdoses and drug abuse skyrockets, children of opioid-dependent parents are at increased risk of being neglected, abused or orphaned. While some studies have examined the effects of policies introduced by states to restrict prescription drug supply on drug abuse, there is no study analyzing their effects on children. This paper estimates the effect of must-access prescription drug monitoring programs (PDMPs) on child removals. To identify the effects of the programs on foster care caseloads, we exploit the variation across states in the timing of adoption of must-access PDMPs using an event-study approach as well as standard difference-in-difference models. Consistent with previous evidence examining the effects of PDMPs on drug abuse, we find that operational PDMP did not have any significant effects on foster care caseloads. However, the introduction of mandatory provisions reduced child removals by 10%. Exploring the reasons of removals, we show that these effects are driven by the reductions in cases of child neglect. There is also evidence of significant reductions in removal cases associated with child physical abuse.
Compressed sensing hyperspectral imaging in the 0.9-2.5 μm shortwave infrared wavelength range using a digital micromirror device and InGaAs linear array detector.

A hyperspectral imaging system based on compressed sensing has been developed to image in the 0.9–2.5 μm shortwave infrared wavelengths. With a programmable digital micromirror device utilized as spatial light modulator, we have successfully performed spectrally resolved image reconstruction with a 256-element InGaAs linear array detector without traditional raster scanning or a push-broom mechanism by a compressed sensing (CS) single-pixel camera approach. The chemical sensitivity of the imaging sensor to near-infrared (NIR) overtone signatures of hydrocarbons was demonstrated using hydrocarbon and ink patterns on glass, showing spectral selectivity for the chemical components. Compared to point-by-point raster scanning, we show that the CS scheme can effectively accelerate image acquisition with lower but reasonable quality.
Socioeconomic Impacts and Social Implications of Reducing Pesticide and Agricultural Chemical Use in the United States

The struggle over agricultural pesticides, which will soon enter its fourth decade, has long involved conflicting interests, opposing ideologies, and contradictory technical and social science data. This paper will focus on one dimension of these conflicts: debate over the prospective socioeconomic impacts of substantial reductions in the use of pesticides and other agricultural chemicals. Research on this topic is obviously central to pesticide politics and policy, since both sides of the struggle ultimately base their positions on claims that chemicals are or are not integral to the social and economic well-being of agriculturalists and of society as a whole.
Tumors of the Digestive System

Tissue from the alimentary canal, the hepatobiliary system, and the pancreas accounts for a significant portion of the day-to-day surgical pathology material in most diagnostic pathology laboratories. While many of the tumors encountered in these specimens are microscopically identical to homonymous tumors in other parts of the body and are graded similarly, some are unique to the gastrointestinal system. This chapter reviews the grading of the most common neoplasms of the digestive system. Several grading systems exist. In this chapter, we essentially adhere to the schemas agreed upon at the editorial and consensus conference of the International Agency of Research for Cancer (Lyon) December 2009 and published as the World Health Organization (WHO) Classification of Tumours of the Digestive System (Bosman et al. 2010).
Computer Self-Administered Screening for Substance Use in University Student Health Centers.

AbstractObjective: To characterize the prevalence of tobacco, alcohol, and drug use and the acceptability of screening in university health centers. Participants: Five hundred and two consecutively...
Assessing the relationship between satellite-derived NO2 and economic growth over the 100 most populous global cities

Satellites offer an unprecedented opportunity to evaluate patterns and trends in air pollution, especially in regions with few or no ground-based monitors. We evaluate the 100 most populous cities worldwide, comparing nitrogen dioxide (NO2) vertical column densities from the Aura satellite to population, gross urban product (GUP), and emissions estimates. We find a positive relationship between GUP and NO2 for 38 of the 56 low-income cities, where NO2 increases with GUP, and a negative relationship for the 7 high-income cities, where NO2 decreases with GUP. This trend is consistent with the environmental Kuznets curve model. However, we found the GUP of 36 cities in the middle range of incomes did not display any consistent relationship with NO2. This partial Kuznets curve relationship arises across the 2005 to 2011 years of our study period, where specific cities show a positive or negative trend in NO2 with GUP growth over time. We analyze a global emissions inventory to compare the relationship between GUP per capita and pollution, which shows a similar relationship. The difference between observed NO2 and the emissions inventory could be due to atmospheric processes or could be due to city-specific changes in energy that are not well captured in the inventory.
Next Generation Ionospheric Heater Array

An electrically small antenna (ESA) is evaluated for its potential future use in a Transportable Ionospheric Heating (TIH) array. Consisting of a Small Loop Antenna (SLA) which inductively couples to a Capacitively Loaded Loop (CLL) the antenna provides a high-Q natural match to a $50 \Omega $ source. The capacitance of the CLL may be adjusted to tune the antenna in the range of ionospheric heating of approximately 3 – 10 MHz. Several methods are evaluated to achieve this tuning including a horizontal sliding plate design, and a hinged petal design.
Implementation of an Obstructive Sleep Apnea Screening Tool with Hypertensive Patients in the Primary Care Clinic

Background and purpose Patients with severe obstructive sleep apnea (OSA) have an almost 4-fold higher odds of resistant hypertension than those with less severe OSA. Obstructive sleep apnea screening practices in primary care are deficient. Additional study is needed regarding the value of OSA screening in hypertensive adults who present to the primary care clinic. Methods This was a convenience sample of adults with hypertension from a rural primary care clinic in Iowa. Staff identified patients who met the inclusion criteria for the project. The STOP-Bang Questionnaire was used to screen the patients for OSA. Providers subsequently used discretion as to ordering polysomnography (PSG). Conclusions Thirty-two patients were screened over a 3-month time period. All of the men included in the study scored either high or intermediate risk for OSA. Forty percent of the study participants scored high risk for OSA, with 33% of those participants referred for PSG. At project conclusion, three participants had undergone PSG testing, and all were diagnosed with sleep apnea. Implications for practice To ensure timely diagnosis and treatment of OSA, primary care providers should consider screening all hypertensive adults for OSA. With compulsory screening and subsequent identification and treatment of patients with OSA, nurse practitioner providers can pave the way in reducing mortality and morbidity associated with OSA, as well as resistant hypertension.
The Corrosion and Biofouling Characteristics of Sealed vs. Perforated Offshore Monopile Interiors Experiment Design Comparing Corrosion and Environment Inside Steel Pipe

Internal corrosion, chemistry and biofouling inside partially submerged hollow steel pipes are evaluated. Watertight pipes with stagnant water inside are compared to pipes with holes that allow circulation with the surrounding seawater.This experiment investigates the issue of whether perforated steel towers could be an improved design for steel monopiles that are presently used for shallow water offshore wind structures. By adding holes to the structure walls, surrounding seawater will consistently flush the internal space. This will create a habitat for marine life, and cathodic protection can be applied to protect the interior steel as it is applied to the external surface. Perforations could provide a potential solution for future designs and preliminary measurements have demonstrated significant differences in water chemistry and corrosion.
METASTATIC PERICARDIAL MESOTHELIOMA: A RARE CASE OF CONSTRICTIVE PERICARDITIS

Malignant pericardial mesothelioma accounts for 2-3% of all pericardial tumors, and its prevalence in the general population is <0.002%. Risk factors include asbestos exposure, genetic susceptibility, infection, and radiation exposure. The disease carries a poor prognosis with a median survival of
Exploring thiophene desulfurization: The adsorption of thiophene on transition metal surfaces

Abstract We study the adsorption of thiophene on Al(100), Ir(100), W(100), Mo(100), Cr(100), Ta(100), Nb(100), V(100), and Co(10–10) surfaces using density functional theory specifically the van der Waals inclusive optB88-vdW functional. We present a thorough report detailing the geometric and electronic structure of the adsorbate/substrate systems including adsorption heights, adsorption energies, buckling of the first layer of the substrate, C–S bond distances, modification of the surface's d-band, change in the surface's work function, and charge transfer to the thiophene molecule. Altogether, we observe a breaking of a single C–S bond when thiophene adsorbs over Mo(100), and the breaking of up to two C–S bonds when thiophene adsorbs over Cr, Ta, Nb, and V (100). We note a direct correlation between the charge transferred to the thiophene molecule, specifically thiophene's S atom, and thiophene's propensity to break C–S bonds over these surfaces, leading us to frame the desulfurization of thiophene as a process governed by charge transfer.
Improving Estuarine Transport Models using Satellite Measurements

Abstract : Satellite measurements of coastal and estuarine water level, water temperature, salinity, and turbidity continue to improve and now provide an opportunity to interpret coastal processes over an unprecedented range of spatial scales. Because these measurements are surface manifestations of tidal processes, river flow, and bathymetry, they can be used to obtain information about underlying physical characteristics. Improved understanding of the underlying physical processes that produce remotely-sensed surface patterns provides a means for testing and improving transport models, particularly in areas in which limited or no measurements are available.
Beyond Suction-Feeding Fishes: Identifying New Approaches to Performance Integration During Prey Capture in Aquatic Vertebrates

Organisms are composed of hierarchically arranged component parts that must work together to successfully achieve whole organism functions. In addition to integration among individual parts, some ecological demands require functional systems to work together in a type of inter-system performance integration. While performance can be measured by the ability to successfully accomplish ecologically relevant tasks, integration across performance traits can provide a deeper understanding of how these traits allow an organism to survive. The ability to move and the ability to consume food are essential to life, but during prey capture these two functions are typically integrated. Suction-feeding fishes have been used as a model of these interactions, but it is unclear how other ecologically relevant scenarios might reduce or change integration. To stimulate further research into these ideas, we highlight three contexts with the potential to result in changes in integration and underlying performance traits: (1) behavioral flexibility in aquatic feeding modes for capturing alternative prey types, (2) changes in the physical demands imposed by prey capture across environments, and (3) secondary adaptation for suction prey capture behaviors. These examples provide a broad scope of potential drivers of integration that are relevant to selection pressures experienced across vertebrate evolution. To demonstrate how these ideas can be applied and stimulate hypotheses, we provide observations from preliminary analyses of locally adapted populations of Trinidadian guppies (Poecilia reticulata) capturing prey using suction and biting feeding strategies and an Atlantic mudskipper (Periophthalmus barbarus) capturing prey above and below water. We also include a re-analysis of published data from two species of secondarily aquatic cetaceans, beluga whales (Delphinapterus leucas) and Pacific white-sided dolphins (Lagenorhynchus obliquidens), to examine the potential for secondary adaptation to affect integration in suction prey capture behaviors. Each of these examples support the broad importance of integration between locomotor and feeding performance but outline new ways that these relationships can be important when suction demands are reduced or altered. Future work in these areas will yield promising insights into vertebrate evolution and we hope to encourage further discussion on possible avenues of research on functional integration during prey capture.
Classifying environmental features from local observations of emergent swarm behavior

Robots in a swarm are programmed with individual behaviors but then interactions with the environment and other robots produce more complex, emergent swarm behaviors. One discriminating feature of the emergent behavior is the local distribution of robots in any given region. In this work, we show how local observations of the robot distribution can be correlated to the environment being explored and hence the location of openings or obstructions can be inferred. The correlation is achieved here with a simple, single-layer neural network that generates physically intuitive weights and provides a degree of robustness by allowing for variation in the environment and number of robots in the swarm. The robots are simulated assuming random motion with no communication, a minimalist model in robot sophistication, to explore the viability of cooperative sensing. We culminate our work with a demonstration of how the local distribution of robots in an unknown, office-like environment can be used to locate unobstructed exits.
Assignment Algorithms for Variable Robot Formations.

This paper describes algorithms to perform optimal assignment of teams of robots translating in the plane from an initial formation to a variable goal formation. We consider the case when each robot is to be assigned a goal position, the individual robots are interchangeable, and the goal formation can be scaled or translated.We compute the costs for all candidate pairs of initial, goal robot assignments as functions of the parameters of the goal formation, and partition the parameter space into equivalence classes invariant to the cost order using computational geometry techniques. We compute a minimum completion time assignment for an equivalence class by formulating it as a linear bottleneck assignment problem (LBAP). To improve efficiency, we solve the LBAP problem for each equivalence class by incrementally updating the solution as the formation parameters are varied. This work is motivated by applications that include the motion of droplet formations in digital microfluidic lab-on-a-chip devices, and of robot and drone formations in the plane.
Officer Supervision Styles and Female Probationer/Parolee Recidivism

Research shows that community supervision officer-client relationships have a meaningful impact on probationer/parolee recidivism; however, such understanding is generally limited to male or juveni...
Experiences of violence and mental health outcomes among Asian American transgender adults in the United States.

Purpose We addressed prevalence and factors associated with mental health outcomes (suicidal behavior and psychological distress) among Asian Americans (AA), who identify as transgender, a key group among sexual and gender minorities that is overlooked and understudied. Methods We used data from 2015 United States Transgender Survey during 2019-2020 with our population as census defined AA. Outcomes included suicidal ideation, suicidal thoughts, and serious psychological distress (SPD). Independent variables included any abuse, partner abuse, bathroom-related abuse, and additional covariates. Adjusted odds ratio and 95% confidence interval (aOR; 95% CI) for each outcome are adjusted for age, marital status, citizenship status, education level, employment status, as well as poverty status. Results Nearly 67% reported experiencing any abuse, 52% reported abuse from romantic/sexual partner(s), while 29% reported harassment/abuse when trying to use bathrooms. Moreover, 82% reported suicidal thoughts, 40% reported suicidal attempts, and 39% had SPD. Results demonstrated that any abuse/violence had higher odds of suicidal thoughts (adjusted odds ratio [aOR] = 2.67, 95% confidence interval (CI):[1.98-3.58], suicidal attempts (aOR = 2.83, 95% CI:[2.18-3.68]), and SPD (aOR = 1.56, 95% CI:[1.20, 2.04]). Abuse from romantic/sexual partners had higher odds of suicidal thoughts (aOR = 2.47, 95% CI:[1.76-3.47]), suicidal attempts (aOR = 2.17, 95% CI:[1.68-2.80]), and SPD (aOR = 2.72, 95% CI:[2.03-3.63]). Experience of harassment/abuse during bathroom use had increased odds of suicidal attempts (aOR = 1.81, 95% CI:[1.41-2.31]). Conclusion Exposure to violence is common among AA transgender individuals and related to negative mental health outcomes. Initiatives to reduce exposure to abuse and providing resources for trauma-informed care are imperative to improve health outcomes.
Partitioning of 1,2-dichlorobenzene onto organic and inorganic aerosols

Environmental context Contaminants adsorbed in aerosols are transported and deposited effectively to the respiratory system compared to their vapours. Measuring the extremely low concentration of highly volatile contaminants contained in aerosols is challenging; hence assessing their adverse effects on environmental and human health is less understood. The measured concentrations of these contaminants are similar to less volatile chemicals sampled from diverse environmental aerosols, suggesting that their contribution cannot be neglected. Abstract Volatile organic compounds (VOCs) are not expected to partition onto aerosols because of their high vapour pressure. Studies on gas–aerosol partitioning of VOCs have been limited because of the challenge in discriminating the small mass fraction of the VOCs in the aerosol relative to that in the gas phase. Here, we developed a bench-scale system to investigate the partitioning of a surrogate VOC, 1,2-dichlorobenzene (1,2-DCB), into inorganic and organic aerosols under different relative humidities (RHs) and temperatures. The partitioning coefficient (Kip) of 1,2-DCB into succinic acid (SA) aerosol was ~10× higher than those into ammonium sulfate (Am Sulf) aerosol. These Kip corresponded to 0.23–3.27 pg 1,2-DCB µg−1 of SA aerosol and 0.02–3.82 pg 1,2-DCB µg−1 of Am Sulf aerosol for RH levels of 5–95 %. Sorption of 1,2-DCB onto Am Sulf aerosol followed the classic relationship between Kip and RH, whereas that onto SA did not. For Am Sulf aerosols, RH levels exceeding 50 % have a negligible effect on partitioning, in which the extremely low amount of 1,2-DCB partitioned into the aerosol via dissolution. The octanol–air partition (KOA) model predicted the Kip of 1,2-DCB for SA aerosol better than the saturated vapour pressure partition (Pi0) model, whereas the Pi0 model predicted Kip better than the KOA model only when absorptive partitioning was considered.
Letting Residents Lead: Implementing Resident Admission Triage Call Curriculum and Practice

BACKGROUND AND OBJECTIVES: Graduating residents are expected to be competent in triaging patients to appropriate resources. Before 2017, pediatric residents were not involved in admission triage decisions. In 2017, after implementing an admission triage curriculum (ATC), residents had opportunities to be involved in overnight admission calls with the emergency department (ED), which were initially supervised (joint calls), and as skills progressed, residents conducted calls and admitted patients independently. We implemented and evaluated the impact of a graduated ATC intervention bundle on pediatric resident opportunities to participate in admission triage, while monitoring resident confidence, the ED experience, and patient safety. METHODS: We evaluated the impact of our ATC using quality improvement methodology. The primary outcome was the frequency of resident participation in joint and independent triage calls. Other measures included resident confidence, the ED clinician experience, and patient safety. Resident confidence and the ED clinician experience were rated via surveys. Safety was monitored with daytime hospitalist morning assessments and postadmission complications documented in the medical record. RESULTS: The percent of joint calls with the hospitalist increased from 7% to 88%, and 125 patients were admitted independently. Residents reported significant increases in adequacy of triage training and confidence in 3 triage skills (P CONCLUSIONS: Our ATC intervention bundle increased the number of admission decision opportunities for pediatric residents, while increasing resident triage confidence, maintaining safety, and improving ED clinician experience.
Deficits in access consciousness, integrative function, and consequent autonoetic thinking in schizophrenia.

Abstract Alterations within consciousness in schizophrenia can be evidenced by impediments in self-awareness and loss of agency. Ned Block’s definition of access consciousness is applied in order to further delineate cognitive deficits involving reflective thought and autonoetic thinking in persons with schizophrenia. Current theories on the nature and functioning of consciousness are discussed, which include Global Workspace Theory and metarepresentational characterizations. These describe a recursive, integrative quality to consciousness, contributed to by the functions of access consciousness, that is relevant in examining cognitive deficits in schizophrenia. The integrative deficit that is described as operating in conscious process involves a failure to incorporate prior outputs from a separate cognitive task and integrate these into a novel working schema. The alterations in access consciousness in persons with schizophrenia appear to be a consequence of disrupted integrative cognitive functions. An anteceding problem with cortical circuits involving integrative functions related to access consciousness is therefore hypothesized to manifest as subsequent cognitive dysfunction that leads to symptoms of schizophrenia. Constitutive failures to integrate information in schizophrenia could lead to an inability to create experiential unity and manage content in autonoetic consciousness. Some of the aberrant reasoning manifested by persons with schizophrenia, including problems with hierarchical relational reasoning, model-based-learning, J-con, ipseity, and source monitoring, could also reflect alterations in access consciousness, and their investigation offers additional approaches for scientific inquiry.
Sustaining strategic advantage in the information age

In the information age, the dynamics of competition is intensifying. In such dynamic environments, how long can firms exploit an (IT based) advantage? We classify various well known IT strategy frameworks by the strategy theory they are based on and summarize their basic logic. We show that traditional strategy thinking ignores speed of change or dynamics of competition. A new strategy framework, sustainability analysis (J.R. Williams, 1992; 1998), extends strategy theory, and takes into account dynamics and different speeds of change. We describe this new strategy framework and how it advances our understanding regarding the sustainability of a competitive (IT based) advantage.
EFFECT OF 1, 25 DIHYDROXYCHOLECALCIFEROL |[lpar]|1, 25 D3|[rpar]| ON LEUKOCYTE GAMMA GLUTAMYL TRANSPEPTIDASE |[lpar]|GGTP|[rpar]|

GGTP is a membrane enzyme necessary in the transfer of some amino acids into the cytosol as a primary event in protein synthesis. Mechanisms of 1,25 D3 in promoting protein synthesis in corporal cells need further elucidation. Circulating leukocytes offer a readily accessible modality for assay of cellular enzyme activity. We, therefore, studied the effects of 1,25 D3 on growth and GGTP activity in young male Wistar rats. The animals were allowed ad libitum feeding of standard Purina Lab Chow during a period of 21 days. Vitamin D supplemented animals received daily injections of 50 pMol 1,25 D3 in 0.2 ml polyethylene glycol(PEG). Control animals were injected with 0.2 ml PEG alone. At sacrifice, leukocyte GGTP was assayed. Growth parameters and enzyme activity are shown below: (Mean± S.D.; *Indicates Difference p <0.05)
Automated Missed-Thrust Propellant Margin Analysis for Low-Thrust Trajectories

Spacecraft employing low-thrust propulsion must be able to recover from an event in which the spacecraft stops thrusting due to an unforeseen problem. Extra propellant is carried to allow the spacecraft to reach its target in the form of propellant margin. An automated method is presented for estimating the propellant margin a spacecraft should carry. The method is applied to three cases: a transfer to Mars, a gravity-assist trajectory to the asteroid Psyche, and a solar sail transfer to the near-Earth asteroid 1991 VG. Examining different power levels for the Mars transfer, it is shown that a 5% margin is sufficient to recover from a 20 days missed thrust for a 10 kW spacecraft, whereas a 15% margin is required for a 20 kW spacecraft. The gravity-assist case exhibits greater sensitivity to missed thrust, but this problem is alleviated by adding a coast arc before the gravity assist in the nominal case. For the solar sail mission, a spacecraft outage of more than 10 days late in the mission may delay arri...
Combining Estimates of Tectonic Plate Rotations

The relative motion between two diverging tectonic plates is a rotation of the sphere. Given measurements of points on the boundaries of the plates, the rotation can be estimated by minimizing a function which is asymptotically (as the concentration parameter of the data distribution goes to infinity) the sum of squared residuals of a linear regression. The linear approximation permits construction of an asymptotic confidence region for the rotation. To estimate the relative motion between plates that converge, it is necessary to combine two or more rotations of diverging plates, and previous methods required the assumption that separate data sets for all of the rotation estimates have the same concentration parameter. This assumption is frequently contradicted by data, indicating heteroscedasticity in the linear regression model. One successful approach to the problem in the linear model due to Welch, involves sample size asymptotics. A similar solution in the non- linear model thus depends on two kinds of asymptotics. We examine two types of general spherical regression models where the parameter estimate is obtained by maximizing or minimizing a particular function. We establish conditions under which the function converges to a residual sum of squares of linear regression as both concentration parameter and sample size go to infinity. Applying the double-convergence asymptotics to tectonic plate data yields asymptotic confidence regions for combined rotation estimates. The confidence region constructions we propose are appropriate for small to moderate sample sizes. Two kinds of confidence regions are constructed, one of which uses all the data for the separate rotation estimates; the other is a conservative approximation of the first, using only summary statistics from the separate estimates. Simulation runs indicate that both of the new constructions produce confidence regions much more consistent with nominal size, particularly when sample sizes are very different and concentration parameters of the data sets are very unequal.
Inactivation-reactivation of aconitase in Escherichia coli. A sensitive measure of superoxide radical.

The rapid inactivation of aconitase by O2-, previously seen to occur in vitro, was explored in vivo. A fraction of the aconitase in growing, aerobic, Escherichia coli is inactive at any instant but can be activated by imposition of anaerobic conditions. This reactivation occurred in the absence of protein synthesis and was inhibited by the ferrous chelator alpha,alpha‘-dipyridyl. This fraction of inactive, but activatable, aconitase was increased by augmenting O2- production with paraquat, decreased by elevation of superoxide dismutase, and increased by inhibiting reactivation with alpha,alpha‘-dipyridyl. The balance between inactive and active aconitase thus represented a pseudoequilibrium between inactivation by O2- and reactivation by restoration of Fe(II), and it provided, for the first time, a measure of the steady-state concentration of O2- within E. coli. On this basis, [O2-] was estimated to be approximately 20-40 pM in aerobic log phase E. coli containing wild type levels of superoxide dismutase and approximately 300 pM in a mutant strain lacking superoxide dismutase.
Surveillance of urothelial carcinoma: stage and grade migration, 1993-2005 and survival trends, 1993-2000.

BACKGROUND: Previous investigators have detected shifts to lower stages at diagnosis for renal cell carcinoma and prostate cancer. The authors investigated whether a similar pattern is seen for urothelial carcinomas of the bladder, ureter, and renal pelvis and sought to identify changes in cancer grade and survival trends from 1993 to 2005. METHODS: The National Cancer Data Base (NCDB) collects data on approximately 75% of all newly diagnosed cancer cases annually. The authors queried the database for cases of urothelial carcinomas diagnosed in 1993-2005 in patients aged 18 years and older. All cancer stage data were forward converted to the sixth edition of the American Joint Committee on Cancer staging definitions. RESULTS: A total of 334,480 bladder cancer cases, 15,105 renal pelvis cancer cases, and 10,128 ureteral carcinoma cases were identified. Stage data were available for 84% of bladder cases, 83% of renal pelvis cases, and 82% of ureter cases. With the classification of early stage tumors as stage 0a, 0is, and I and late stage tumors as II, III, and IV, the percentage of early stage renal pelvis and ureter tumors increased slightly from 1993 to 2005, whereas no stage migration was seen in bladder tumors. In looking specifically at early stage tumors, a significant increase in the proportion of stage 0a and a significant decrease in the proportion of stage I tumors for each cancer site was seen between 1993 and 2005. The proportion of high grade tumors in each disease site significantly increased from 1993 to 2005. For cases diagnosed in 1993-1996 and 1997-2000, a significant decrease in 5-year relative survival was observed for patients with stage I and stage II bladder cancer. The absolute change, however, was relatively small, and for bladder cases was not significantly different when adjusted for low or high grade tumors. CONCLUSIONS: When differentiating between early and late stage tumors, a slight stage migration was seen in renal pelvis and ureteral carcinomas, whereas no stage migration was seen in bladder tumors. Within early stage tumors of all sites, a stage shift was seen, most notably with the proportion of stage 0a tumors increasing and stage I tumors decreasing. The proportion of high grade tumors in all sites increased. No change in overall survival was observed, underscoring the need for new therapeutic advances. Cancer 2009. © 2009 American Cancer Society.
Palmitylation of a G-protein coupled receptor. Direct analysis by tandem mass spectrometry.

Bovine rhodopsin has been reported to be S-palmitylated at cysteines 322 and 323 (Ovchinnikov, Y. A., Abdulaev, N. G., and Bogachuk, A.S. (1988) FEBS Lett. 230, 1-5). Using a combination of enzymatic and chemical cleavage techniques in conjunction with tandem mass spectrometry, the sites of incorporation of the palmityl groups are shown. Bovine rhodopsin in disc membranes was digested with thermolysin to generate the C-terminal fragment (241-327), which was subsequently cleaved with cyanogen bromide to generate the peptide Val-Thr-Thr-Leu-Cys-Cys-Gly-Lys-Asn-Pro (318-327). A bis-S-palmitylated synthetic standard had the same retention time by reversed-phase high performance liquid chromatography as the isolated peptide and the same molecular weight (MH+1511.7) by liquid secondary ion mass spectrometry. Dithiothreitol reduction of both the isolated and the synthetic peptide cleaved the two thioester-linked palmityl groups to produce reduction products of the same appropriately decreased molecular weight (MH+1035.5). Tandem mass spectrometry of the isolated and the synthetic peptide identified the sites of attachment of the palmityl groups on cysteines 322 and 323. These results prove the modification of cysteines 322 and 323 with palmitic acid in bovine rhodopsin, and illustrate the utility of mass spectrometry to characterize the post-translational modifications in G-protein coupled receptors.
Neighborhood Influences on Adolescent Development

Methodological Issues in Studying Adolescent Development in Neighborhood Contexts A Review of Neighborhood Structural Effects on Adolescent Development A Framework for Understanding Potential Pathways of Neighborhood Effects on Adolescent Outcomes Emerging Trends and Unresolved Issues Policy Implications and Future Directions Keywords: neighborhood; community; socioeconomic status; poverty; achievement; mental health; sexual behavior
Nutritional rickets among children in the United States: review of cases reported between 1986 and 2003.

Reports of hypovitaminosis D among adults in the United States have drawn attention to the vitamin D status of children. National data on hypovitaminosis D among children are not yet available. Reports from 2000 and 2001 of rickets among children living in North Carolina, Texas, Georgia, and the mid-Atlantic region, however, confirmed the presence of vitamin D deficiency among some US children and prompted new clinical guidelines to prevent its occurrence. We reviewed reports of nutritional rickets among US children < 18 y of age that were published between 1986 and 2003. We identified 166 cases of rickets in 22 published studies. Patients were 4-54 mo of age, although in 17 studies the maximal age was < 30 mo. Approximately 83% of children with rickets were described as African American or black, and 96% were breast-fed. Among children who were breast-fed, only 5% of records indicated vitamin D supplementation during breast-feeding. The American Academy of Pediatrics (AAP) recently recommended a minimal intake of 200 IU/d vitamin D for all infants, beginning in the first 2 mo of life. AAP recommends a vitamin D supplement for breast-fed infants who do not consume at least 500 mL of a vitamin D-fortified beverage. Given our finding of a disproportionate number of rickets cases among young, breast-fed, black children, we recommend that education regarding AAP guidelines emphasize the higher risk of rickets among these children. Education should also emphasize the importance of weaning children to a diet adequate in both vitamin D and calcium.
Has the age of political giants passed

Today's politicians start and exit politics younger; they lack heft, stature and outside interests; they are bred into an ever-narrower political class; and they preside over tame and depleted political parties. Should we be waiting for another Churchill, asks David Runciman, or are we measuring today's politicians against the wrong yardsticks?
Carbonyl participation in the reaction of N-acyl-2-isopropenylpyrrolidines with halogen electrophiles. Stereocontrolled preparation of enantiomerically pure synthons for the synthesis of pumiliotoxin A alkaloids.

Abstract Allylic carbamate 4 and allylic benzamide 12 react with halogen electrophiles with high 1,2-relative asymmetric induction via carbonyl participation.
Retail and wholesale enterprise among ethnic groups in core and peripheral urban centers: the late-nineteenth-century United States

Ethnic entrepreneurs often benefit from reciprocal relationships, such as buyer–supplier linkages, among co-ethnic businesses. The present study extends this insight, analyzing census data on the relationship between ethnic enterprise in the retail trade and co-ethnic enterprise in the wholesale trade in urban centers of core and peripheral regions of the late-nineteenth-century United States. As expected, this relationship varied markedly by ethnicity and region. For some groups (e.g., Russians), co-ethnic retail and wholesale enterprises were positively related on the periphery but not in the core; conversely, for other groups (e.g., Irish), co-ethnic retail and wholesale enterprises were positively related in the core but not on the periphery. The results imply that reciprocal relationships among co-ethnic businesses are significantly affected by variation in the characteristics of local opportunity structures across urban-regional locations.
Tubular Ice Crystals

IT has been found that on very rare occasions long, thin ice needles grow into the air from the solid surface of water frozen in an open container1–4. In the course of supercooling experiments, Dorsey5 observed a similar phenomenon in the laboratory. He assumed that growth occurred when, because of the increase in volume during solidification, water was forced through an opening in the ice covering the surface. Dorsey also suggested that a tube formed, through which water flowed and which “grew” at its tip. Recently, Hayward6 reported a method for growing such spikes and obtained experimental evidence in support of Dorsey's mechanism.
The Messages behind the Methods: The Authoritarian Pedagogical Legacy in Western Concert Dance Technique Training and Rehearsals

(2005). The Messages behind the Methods: The Authoritarian Pedagogical Legacy in Western Concert Dance Technique Training and Rehearsals. Arts Education Policy Review: Vol. 106, No. 5, pp. 3-20.
A Mechanism for Repressor Action

Abstract Deletion mutants have been isolated in which the three structural genes of the lac operon, z , y and a , and the lac operator are fused to the trp operon. In most of these strains, the rate of lac operon expression is greatly increased by the derepression of the trp operon. Under such derepression conditions, the transcription of lac which is presumably initiated at the trp promoter site can be partially blocked by the attachment of lac repressor to lac operator DNA. These findings suggest that the lac repressor is capable of blocking progress of RNA polymerase. Furthermore, properties of certain of these fusion strains suggest that there is a barrier to continued messenger RNA synthesis (messenger RNA stop signal) at the C-terminal end of the i gene.
Effects of age on children's intake of large and self-selected food portions.

Objective: Whether developmental periods exist in which children become particularly sensitive to environmental influences on eating is unclear. This research evaluated the effects of age on intake of large and self-selected portions among children 2 to 9 years of age. Research Methods and Procedures: Seventy-five non-Hispanic white children 2 to 3, 5 to 6, and 8 to 9 years of age were seen at a dinner meal in reference, large, and self-selected portion size conditions in which the size of an entree was age-appropriate, doubled, and determined by the child, respectively. Weighed food intake data were collected. Entree bite size and bite frequency were assessed. Height and weight measurements were obtained. Results: The effect of age on children's intake of the large portion was not significant. Entree consumption was 29% greater (p < 0.001) and meal energy intake was 13% greater (p < 0.01) in the large portion condition than in the reference condition. Increases in entree consumption were attributable to increases in average bite size (p < 0.001). Neither child weight nor maternal weight predicted children's intake of large portions. Self-selection resulted in decreased entree (p < 0.05) and meal energy (p < 0.01) only among those children who ate more when served the large portion. Discussion: The results of this research confirm that serving large entree portions promotes increased intake at meals among 2- to 9-year-old children. These findings suggest that any age-related differences in children's response to large portions are likely to be smaller than previously suspected.
Behavioral and anatomical characterization of the bilateral sciatic nerve chronic constriction (bCCI) injury: correlation of anatomic changes and responses to cold stimuli

Unilateral constrictive sciatic nerve injury (uCCI) is a common neuropathic pain model. However, the bilateral constrictive injury (bCCI) model is less well studied, and shows unique characteristics. In the present study, we sought to correlate effects of bCCI on nocifensive responses to cold and mechanical stimuli with selected dorsal horn anatomic markers. bCCI or sham ligation of both rat sciatic nerves were followed up to 90 days of behavioural testing. Additional rats sacrificed at 15, 30 and 90 days were used for anatomic analyses. Behavioural tests included hindpaw withdrawal responses to topical acetone, cold plate testing, an operant thermal preference task and hindpaw withdrawal thresholds to mechanical probing. All nocifensive responses to cold increased and remained enhanced for >45 days. Mechanical withdrawal thresholds decreased for 25 days only. Densitometric analyses of immunoperoxidase staining in the superficial dorsal horn at L4-5 revealed decreased cholecystokinin (CCK) staining at all times after bCCI, decreased mu opiate receptor (MOR) staining, maximal at 15 days, increased neuropeptide Y (NPY) staining only at days 15 and 30, and increased neurokinin-1 receptor (NK-1R) staining at all time points, maximal at 15 days. Correlation analyses at 45 days post-bCCI, were significant for individual rat nocifensive responses in each cold test and CCK and NK-1R, but not for MOR or NPY. These results confirm the usefulness of cold testing in bCCI rats, a new approach using CCI to model neuropathic pain, and suggest a potential value of studying the roles of dorsal horn CCK and substance P in chronic neuropathic pain. Compared to human subjects with neuropathic pain, responses to cold stimuli in rats with bCCI may be a useful model of neuropathic pain.
Improved bracing compliance in children with clubfeet using a dynamic orthosis

Abstract Purpose Non-compliance with foot abduction bracing in children with clubfeet treated with the Ponseti method is the leading risk factor for deformity recurrence. A dynamic foot abduction orthosis is believed to result in improved compliance, fewer skin complications, and fewer recurrences. A case–control trial was conducted to test this hypothesis. Methods A prospective cohort of children with idiopathic clubfoot using a dynamic brace was compared to a historical control group treated with a standard orthosis. Compliance, skin complications, recurrence, and the need for surgical soft tissue release were compared between groups at equivalent follow-up. Results The dynamic and standard brace groups are equivalent in age at the start of treatment (1.9 vs. 2.9 months), number of affected feet (97 vs. 92), and severity (average of four casts required for correction in each group). Fifty-seven children were followed in each group for an average of 2 years. All were corrected initially with the Ponseti ...
Existence of Maximum Likelihood Estimates for Multi-dimensional Exponential Families

This paper deals with the existence of maximum likelihood estimators for multi-dimensional exponential families, including curved exponential families. It first gives an algorithm for determining the MLE from the data. Then it establishes that when the parameter set is either open or relatively closed in the natural parameter set, the MLE of the parameter exists in the sense of Hoffmann-Jorgensen.
Solution of the plane end problem for a semi-infinite elastic strip

The end problems of arbitrary traction, displacement, and mixed boundary conditions are all solved by the superposition of half-plane and infinite strip solutions. The solutions obtained involve singular integral equations, which are analyzed directly to determine the solution singularities at the corners. The solutions are applied to several specific problems in which pointwise end conditions are prescribed including extension, bending, and flexure for a fixed end; compression against a smooth and rough circular cylinder; and extension and bending by cosine and sine normal tractions. Numerical results are given for most of these solutions.
Stepwise Assembly of a Relaxosome at the F Plasmid Origin of Transfer

A central step in the transfer of genetic information during bacterial conjugation of the Escherichia coli F plasmid involves the formation of a protein-DNA complex, called the relaxosome, at the origin of transfer. During conjugation, the relaxosome introduces a site- and strand-specific nick from which the physical transfer of a single strand of DNA is initiated. At least two F-encoded proteins, TraIp (traI gene product) and TraYp (traY gene product), and one host-encoded protein, integration host factor, are involved in this process. In this report, we use DNase I protection and electron microscopic techniques to investigate the mechanism of relaxosome formation. Our results show that TraYp and integration host factor form a protein-DNA complex that facilitates the binding of TraIp to assemble a relaxosome capable of introducing a site- and strand-specific nick at the origin of transfer. This nick is identical to that observed during conjugation.