cssi/SciSciGPT-SciSciNet huggingface dataset:
An Investigation into Accuracy, Computation, and Robustness of Stochastic Linearization of Systems with Saturation Nonlinearities

Abstract Quasilinear Control (QLC) is a theory with a set of tools that can be used for the analysis and design of stochastic feedback control systems with nonlinear actuators and sensors. It is based on Stochastic Linearization (SL), a method of linearization that approximates a nonlinearity with an equivalent gain and a bias using statistical properties of its input. While the QLC literature has studied many problems in controls (e.g., performance analysis and controller design), important issues such as accuracy, robustness, and computation of SL have not been fully investigated. This paper fills this gap, with a special focus on feedback systems with saturating actuators, which are commonly encountered in feedback control systems and the QLC literature. Specifically, the accuracy of SL in approximating the saturated response is investigated. A mathematical relationship is established between the saturation authority and the worst-case open-loop accuracy, and the implications on closed-loop accuracy are described. To study the robustness of SL in practical situations, the sensitivities of the equivalent SL gain and bias to system parameters are investigated. Finally, several root-finding algorithms are compared in terms of their computational speed in solving the SL equations, and a novel change of coordinates is presented to improve the performance. The results provide valuable insights into and methods for addressing the computational aspects of SL that are critical for proper design and analysis of nonlinear stochastic feedback control systems.
Emergency Department Evaluation of Abdominal Pain in Female Adolescents.

ABSTRACT Study Objective Evaluation of acute abdominal pain in an adolescent female patient should include consideration of all potential sources of pain, including gynecologic etiologies. The goal of our study was to determine the frequency of evaluation of gynecologic causes of abdominal pain in adolescent girls seen in a pediatric emergency department. Study Design A retrospective review was performed of girls between 12 and 21 years of age presenting to the emergency department or urgent care centers at a single pediatric institution with the chief complaint of abdominal pain during 2016. Frequency analyses of demographic and clinical characteristics are presented. Results A total of 1082 girls presented with a chief complaint of abdominal pain. Menarche was documented in 85% of patients, sexual history in 52% of patients, and assessment of contraception use in 28%. Pregnancy testing was performed in 77%. Sexually transmitted infection (STI) testing was performed in 31%, and in only 73% of patients who reported being sexually active. Imaging was performed in 52%. In the subgroup of patients who reported being sexually active and presented with abdominal pain and vaginal discharge, only 37% had a pelvic examination performed. In multivariable modeling, Black patients were significantly more likely than White patients to have STI testing performed (adjusted risk ratio [aRR] = 1.39; confidence interval [CI] = 1.13-1.70) and to undergo a pelvic examination (aRR = 2.45; CI = 1.34-4.50), and less likely to undergo imaging (aRR = 0.69; CI = 0.59-0.81). Conclusion The assessment of abdominal pain in adolescent girls should include gynecologic etiologies. Our results raise concerns that there are deficiencies in the evaluation of gynecologic sources of abdominal pain in girls treated at pediatric facilities, and evidence of potential racial disparities.
Impact of device level faults in a digital avionic processor

This paper describes an experimental analysis of the impact of gate and device-level faults in the processor of a flight control system. Via mixed mode simulation faults were injected both at the gate (stuck-at) and at the transistor levels, and their propagation through the chip to the output pins was measured. The results show that there is little correspondence between a stuck-at and a device-level fault model insofar as error activity or detection within a functional unit is concerned. Insofar as error activity outside the injected unit and at the output pins are concerned, the stuck-at and device models track each other, although the stuck-at model overestimates, by over one hundred percent, the probability of fault propagation to the output pins. The stuck-at model significantly underestimates the impact of an internal chip fault on the output pins.
Validating food establishment risk classification by analyzing health inspections

Public health inspectors may schedule the frequency of their inspections by using a criterion that reflects the level of risk in a food facility’s food handling practices. Previous research has shown that higher risk facilities have more difficulty adhering to food safety practices, and thus are linked with more restaurant associated foodborne illness outbreaks. Given limits on state spending for public health, this methodology of spending more resources on perceived higher risk establishments makes fiscal sense. Foodservice establishments with a greater potential risk for harm are inspected more often. The next logical point would be to record whether the high-risk foodservice establishment had more opportunities for food safety infractions simply because of a greater total observed and applicable food safety practices. For example, there are significant differences in the number of potential food safety violations for a facility that only serves pre-packaged foods compared to a facility that prepares raw ingredients and cooks meals on site. The objective of the present study was to address gaps in the literature by accounting for variations in health inspections in Arkansas validating whether foodservice establishments labeled as higher risk are more likely to incur food safety violations. Our analysis of Arkansas food service inspection reports showed that high priority facilities had the highest critical and non-critical violation rates, followed by medium and low priority facilities. Average critical violations per inspection were 0.65, 1.01, and 2.07 for low, medium, high priority establishments, respectively. The results in this study show the risk classification scheme used by the Arkansas state health department coincides with health inspection violation rates and total applicable and observed food safety items.
Pre-pregnancy Health Behaviors and Gestational Weight Gain Among Hispanic/Latino Women: Hispanic Community Health Study/Study of Latinos.

To examine the association between preconception diet quality, sedentary behavior, and physical activity with gestational weight gain (GWG) among Hispanic/Latina women. This was a retrospective cohort study of participants from visits 1 and 2 of the Hispanic Community Health Study/Study of Latinos and singleton pregnancies between the 2 visits. Diet quality (alternative healthy eating index/AHEI-2010), sedentary behaviors, and physical activity (global physical activity questionnaire) were measured at visit 1 and accounted for preconception health behaviors. GWG was evaluated as a continuous and categorical variable according to the 2009 Institute of Medicine guidelines (inadequate, adequate, excessive). Linear and generalized logit survey regressions were used to study the association between health behaviors and GWG, using adequate GWG as the reference. Of the 457 women included, deliveries occurred at 3.2 years (mean) from visit 1; 48.7% of women had excessive GWG. Mean AHEI-2010 scores were < 45% for women of all Hispanic/Latina backgrounds. There was no association between each 10-unit increase in AHEI-2010 or a 500 kcal/day increase in energy intake for mean and categorical GWG. There was no association between 30 min/day higher sedentary behavior, 30 min/day higher physical activity, or meeting the 2008 US physical activity guidelines for mean and categorical GWG. We did not find any association between diet quality, sedentary behavior, and physical activity at visit 1 with GWG in pregnancies occurring between visits 1 and 2. We noted widespread poor diet quality as measured by the AHEI-2010 and low levels of physical activity among Hispanic/Latina women.
Residential distance from the reporting hospital and survival among adolescents, and young adults diagnosed with CNS tumors.

Prior research shows that residential distance to a treatment facility may be an important factor in central nervous system (CNS) tumor outcomes. Our goal was to examine residential distance to the reporting hospital and overall survival in adolescents and young adults (AYA) diagnosed with CNS tumors. National Cancer Database data on AYA 15–39 years old diagnosed with CNS and Other Intracranial and Intraspinal Neoplasms (CNS tumors) from 2010 to 2014 were obtained. Distance between the case’s residence at diagnosis or initial treatment and the reporting hospital was classified in miles as short (≤ 12.5), intermediate (> 12.5 and < 50), and long (≥ 50). Cox proportional hazards regression models were used for analyses. Among 9335 AYA diagnosed with CNS tumors, hazard ratios (HRs) were 1.06 (95% CI 0.96–1.17) and 0.82 (95% CI 0.73–0.93) for those with residences at intermediate and long vs. short distances, respectively, after adjusting for age, sex, race/ethnicity, and zip-code level education and income. After adjusting for the facility volume of CNS tumor patients, the association was attenuated for long vs. short distance residences (HR 0.92, 95% CI 0.81–1.04). The HRs varied by tumor type, race/ethnicity, and zip-code level income with significantly lower hazards of death for those with residences at long vs. short distances for low-grade astrocytic tumors, ependymomas, non-Hispanic Whites, and those from higher-income areas. Living at long distances for CNS tumor care may be associated with better survival in AYA patients. This may be explained by travel to facilities with more experience treating CNS tumors.
Passive biaxial mechanical behavior of newborn mouse aorta with and without elastin

Abstract Aortic wall material properties are needed for computational models and for comparisons across developmental and disease states. There has been abundant work in comparing aortic material properties across disease states, but limited work across developmental states. We performed passive biaxial mechanical testing on newborn mouse aorta with (Eln+/+) and without (Eln−/−) elastin. Elastin provides elasticity to the aortic wall and is necessary for survival beyond birth in the mouse. Mechanically functional elastin is challenging to create in vitro and so Eln−/− aorta can be a comparison for tissue engineered arteries with limited elastin amounts. We found that a traditional arterial strain energy function provided reasonable fits to newborn mouse aorta and generally predicted lower material constants in Eln−/− compared to Eln+/+ aorta. At physiologic pressures, the circumferential stresses and moduli trended lower in Eln−/− compared to Eln+/+ aorta. Increased blood pressure in Eln−/− mice helps to alleviate the differences in stresses and moduli. Increased blood pressure also serves to partially offload stresses in the isotropic compared to the anisotropic component of the wall. The baseline material parameters can be used in computational models of growth and remodeling to improve understanding of developmental mechanobiology and tissue engineering strategies.
Sensorfusion als strategischer Ansatz fuer Sicherheits- und Assistenzsysteme

Die Funktionalitat aktueller Sicherheitssysteme basiert vor allem auf bereits vorhandenen Sensorinformationen, siehe etwa die elektronischen Fahrdynamik-Regelsysteme oder elektronische Dampferregelung. Die Delphi Corporation nutzt die Daten verschiedener Sensoren (Radar, Lidar, Infrarot und Kameras), um Assistenzfunktionen, wie etwa Spurassistenz, die Fusgangererkennung oder eine adaptive Geschwindigkeitsregelung, zu realisieren. Durch Fusion von Sensordaten wird dieses Potenzial kunftig noch besser erschlossen.
Demand Model for Intercity Multimode Travel

The paper exposes some limitations of the abstract mode model based on the econometric theory as applied to transportation, and suggests modifications for improving its descriptive function as well as predictive capabilities for more accurate travel demand estimations. The modifications included model stratification by trip purpose, suggestions of significant forms of the explanatory variables entering the model, derivation of a time series model for travel forecasts, and the introduction of the dummy variable techniques for modal-split analysis. Habitual travel behavior which provides the theoretical background for the empirical analysis of any travel demand estimation, served as a basis for explaining the modifications. In order to illustrate the aforementioned proposals, versions of the abstract mode model were formulated by using a sample of city-pair data on the intercity passenger travel in West Virginia. A detailed discussion of model formulation procedures is presented. Thus, the aim of the proposed modifications to assist the accuracy of the abstract mode model is substantiated.
Energy Balance in the Interstellar Medium

A large number (approximately 7) of different components or phases are needed to describe the interstellar medium. The neutral intercloud medium is probably a composite of (a) “lukewarm, substandard” clouds (heated by grain photoeffect and shockwaves), (b) the interfaces between clouds and coronal gas and (c) some “phase 2” gas heated by soft X-rays. Ionizing UV photons are mainly produced by OB-stars and are responsible for most of the average electron density. Bulk kinetic energy for “stirring” the medium and soft X-rays are mainly produced by supernova remnants, less by O-star stellar winds.
A study of group size and communication in an evolving fuzzy-controlled population

This research effort is an investigation into communication activity in a distributed set of software agents. Agents exist in a predator-prey environment. Movements of prey agents are evolved upon a Mamdani type fuzzy inference system. Probabilistic predation and starvation forces, along with simulated communication activity act upon agents, causing them to cluster. Examined here is the correlation between mean cluster size after the population has sufficiently evolved, versus the average agent communication activity. Communication activity creates a loyalty to remain in a cluster for security rather than to change cluster membership. A mean r/sup 2/ correlation of 0.87 was observed with this system, thus lending credence to our hypothesis.
Linked and Situated: Grounded Knowledge

Local knowledge registers prominently in scholarly efforts to resolve environmental problems, ushering in widespread use of participatory practices of deliberation. Without the incorporation of local knowledge, many scholars contend that environmental science and planning remain beholden to the unbridled reign of the expert, and the daunting complexity of environmental problems remains seemingly impossible to penetrate. Following in this vein of work, we formed our participatory research project on nonpoint water pollution in two watersheds around four action clusters. On the local side, we included a cluster of farmers and farmland owners and a cluster of general community members. On the expert side, we included a cluster of researchers and another of government officials. However, we found in our research that the development of democratic deliberation depended more on whether participants situated and linked their knowledge than whether it was local or expert in origin. We suggest grounded knowledge, situating one's experiences in a way that enables participants to actively link with other knowledge, as a concept useful for scholars to better understand which ways of knowing enable deliberation in the participatory processes.
Trends and variability in surface ozone over the United States

We investigate the observed trends and interannual variability in surface ozone over the United States using the Global Modeling Initiative chemical transport model. We discuss the roles of meteorology, emissions, and transport from the stratosphere in driving the interannual variability in different regions and seasons. We demonstrate that a hindcast simulation for 1991–2010 can reproduce much of the observed variability and the trends in summertime ozone, with correlation coefficients for seasonally and regionally averaged median ozone ranging from 0.46 to 0.89. Reproducing the interannual variability in winter and spring in the western United States may require higher-resolution models to adequately represent stratosphere-troposphere exchange. Hindcast simulations with fixed versus variable emissions show that changes in anthropogenic emissions drive the observed negative trends in monthly median ozone concentrations in the eastern United States during summer, as well as the observed reduction in the amplitude of the seasonal cycle. The simulation underestimates positive trends in the western United States during spring, but excluding the first 4 years of data removes many of the statistically significant trends in this region. The reduction in the slope of the ozone versus temperature relationship before and after major emission reductions is also well represented by the model. Our results indicate that a global model can reproduce many of the important features of the meteorologically induced ozone variability as well as the emission-driven trends, lending confidence to model projections of future changes in regional surface ozone.
Competition for Food between Crayfish (Orconectes virilis) and the Slimy Sculpin (Cottus cognatus)

ABSTRACT Interspecific competition for a food resource (fish eggs) was examined in a laboratory setting between two common benthic organisms of the Great Lakes, the slimy sculpin (Cottus cognatus) and crayfish (Orconectes virilis). In monospecific tests, the median egg predation in aquarium microcosms ranged from 2.5 eggs/d for the sculpin to 3.0 eggs/d for the crayfish. In mixed-species tests, sculpin feeding rates were no different than in the monospecific tests. Feeding rates for crayfish, however, were significantly reduced by the presence of sculpin. In mixed-species treatments in which small refuges were included in the aquaria, crayfish predation of eggs was 50% less than in the monospecific tests, i.e., 1.5 eggs/d, and, crayfish went on 93% fewer excursions outside refuges, spent 94% less time outside refuges, and engaged in 83% fewer feeding bouts than sculpin (P≤ 0.05 for all comparisons). When no refuges were provided, crayfish ceased feeding (0 eggs/d). These results suggest the potential for ...
Dissolved rare earth elements in a seasonally snow-covered, alpine/subalpine watershed, Loch Vale, Colorado

Dissolved rare earth elements (REEs) were determined in a four-year time series at the outlet of Loch Vale. The Loch Vale watershed is a seasonally snow-covered alpine/subalpine basin in Rocky Mountain National Park, USA. The time series was mainly distinguished by an annual early spring peak in the concentrations of all REEs. REE concentrations at this time were as much as 8-fold greater than at other times of the year. This annual peak was coincident with an early spring peak in dissolved organic carbon (DOC) which results from flushing of soils at the beginning of spring snow melting. The REE/DOC peak occurs as discharge starts to increase from wintertime lows but well before the spring peak in discharge. Speciation considerations suggest complexation of the REEs by DOC. The Ce anomaly also increases (i.e., is less fractionated) during the spring flush indicating that the most reducing (or least oxidizing) REE sources in the system are comparatively more important at that time. Mn data and the La/Yb ratio also support this. The behavior of REEs in the Loch Vale system has additionally been compared with metal and DOC behavior in other systems. Hydrologic and climatic differences can be important especially with regard to timing and duration of the spring flush peak. Damping of hydrologic events in the lower floodplain of major rivers may also partially result in the differences observed between Loch Vale and the lower Mississippi River. However, comparison with the Amazon River system additionally suggests that seasonal flooding of wetlands may be an important regulator of REE concentrations. Chemical differences are also important for these systems. This includes pH and suspended matter concentrations which affect the balance between adsorption and complexation. Additionally, the relative complexing ability of DOC in different systems is a factor needing further consideration.
Identification and intensities of the “forbidden” 3ν23 band of 12C16O2

Abstract Lines of the 3ν23 “forbidden” band of 12C16O2 have been identified in the 2000-cm−1 region of a long-path, 0.01-cm−1 resolution laboratory absorption spectrum. This band has detectable intensity due to Δl = 2 Fermi interactions between the upper level and the nearby ν1 + ν2 and 3ν21 levels. Intensities of 18 lines of this band have been measured using a nonlinear least-squares spectral fitting technique. The intensities are enhanced at high J and an expression for the intensity distribution as derived by Toth [Appl. Opt. 23, 1825–1834 (1984)] is used for the analysis. In terms of the total sample pressure, the vibrational band intensity is 0.194 ± 0.008 × 10−30 cm−1/molecule-cm−2 at 296 K. The coefficient in the F factor is analogous to the Coriolis coefficient ξ and has been determined to be −0.0413 ± 0.0015. As expected by theory, its value is very close to that of ξ for the related ν1 + ν2 band.
Thyroid hormone control of preganglionic innervation of the adrenal medulla and chromaffin cell development in the rat. An ultrastructural, morphometric and biochemical evaluation.

In the rat, functional connections between the splanchnic nerve and the adrenal medulla are immature at birth and do not become fully competent until the first postnatal week. Neonatal administration of triiodothyronine (T3) accelerates this process, and the present study was undertaken to elucidate the underlying mechanisms. Rats were given T3 (0.1 mg/kg, s.c.) daily for 9 days beginning 1 day after birth. Preganglionic innervation of the adrenal medulla was examined by retrograde axonal transport of horseradish peroxidase (HRP). At 10 days of age, there was an increased number of labeled perikarya in the spinal cord of the hyperthyroid pups. Ultrastructural examination revealed a corresponding increase in synaptic density in the adrenal medulla and in the activity of choline acetyltransferase, a marker for preganglionic cholinergic nerve terminals. These effects were attenuated by 25 days of age, whereupon deficits in HRP-labeled neurons and adrenomedullary synapses were noted. Similarly, replication of chromaffin cells was enhanced transiently in the T3 group during the initial stage of hyperthyroidism, but subsequent long-lasting deficits in cell numbers were noted, along with a corresponding retardation of ontogeny of adrenal catecholamine biosynthesis and storage. Thus, neonatal hyperthyroidism accelerates synaptic development in the sympatho-adrenal axis but suppresses maturation of the target chromaffin cells, ultimately leading to, impaired adrenomedullary function.
Mutagenicity of HPLC-fractionated urinary metabolites from 2,4,6-trinitrotoluene-treated Fischer 344 rats.

The production and storage of explosives has resulted in the environmental accumulation of the mutagen 2,4,6-trinitrotoluene (TNT). In order to characterize the production of mutagenic urinary metabolites, 6-week old male Fischer 344 rats were administered 75 mg of TNT/kg or DMSO vehicle by gavage. The animals were placed into metabolism cages, and urine was collected for 24 hr. Following filtration, metabolites in the urine were deconjugated with sulfatase and β-glucuronidase and concentrated by solid phase extraction. The eluate was fractionated by reverse-phase high-performance liquid chromatography (HPLC) using acetonitrile/water, and the fractions were solvent exchanged in DMSO by nitrogen evaporation. Each HPLC fraction was bioassayed in strains TA98, TA98NR, TA100, and TA100NR without metabolic activation using a microsuspension modification of the Salmonella histidine reversion assay. Fractions 3, 5–18, 21, 22, and 24–26 contained mutagens detected by strain TA98. In the nitroreductase-deficient strain TA98NR, some mutagenic activity was lost; however, fractions 3, 6, 9–11, 15, and 25 clearly contained direct-acting mutagens. Fewer fractions were positive in strain TA100 (9–16, 19, 20, and 25) with less activity observed in the nitroreductase deficient strain TA100NR (fractions 3, 12, 14, 15, and 25). Although some mutagenic activity coeluted with known TNT metabolite standards, there were still many unidentified mutagenic peaks. Environ. Mol. Mutagen. 30:298–302, 1997. © 1997 Wiley-Liss, Inc.
Private higher education: The Philippines as a prototype

A high proportion of college and university students in the Philippines attend private institutions, mainly because of limited space in public institutions. The system is examined as a case study for studying certain hypotheses about the impact of substantial private provision on higher education systems. After presenting basic data for the system as a whole the article compares public and private institutions and then explores the policy implications.
A Brief Guide to Student Projects with Industry

Student projects with industry have much to offer in terms of enhanced student learning, but they can be difficult to create, plan, and manage sustainably. This paper details and distills the best practices from a four-year process to develop an undergraduate business strategy course around a student project with industry. This reflexive process revealed that our traditional analytical approach to business strategy was not teaching students how to create strategy in practice. Integration of course learning objectives with project deliverables was a key to replicating a practical project-based learning experience each semester. The needs for an industry liaison, additional student preparation, and active client engagement in the learning process are also discussed.
A comparison of join operations in dBASE IV

Abstract This paper examines three different ways to implement the relational join operation using dBASE IV, the latest version of the popular dBASE microcomputer database management software. After reviewing E.F. Codd's definition of the join, the SET RELATION/SET SKIP, JOIN and SQL SELECT commands are compared and contrasted for their effectiveness in joining tables. It is concluded that the SQL SELECT command is the preferred way to join tables.
Blood Pressure Morning Surge and Hostility

Abstract This study examined the effects of hostility on blood pressure (BP) during the early morning hours before awakening and several hours afterward. Our objective was to determine whether the pattern of BP change and the slope of the morning BP surge were related to hostility. The subjects were 32 patients with a history of Stage 1 hypertension. The morning surge in BP was derived from ambulatory BP monitoring of sleeping and waking hours, which were averaged per subject and centered around the wake-up hour. The periods used were 3 h before and 3 h after awakening. Only systolic blood pressure (SBP) is being reported on in this paper as this is the primary measure found relevant to the morning surge phenomenon. Hostility was assessed by the Buss-Durkee Hostility Inventory (total score). The results revealed significant differences between low and high hostility subjects for overall levels of sleep SBP: 120 ± 11.4 mm Hg for low hostility and 131.3 ± 14.9 mm Hg for high hostility subjects (P = .02). Low hostility subjects showed a steep rise in SBP from sleeping to waking while high hostility subjects had almost reached their post-sleep level of SBP in the hours immediately before waking up (P = .03). These data indicate that individual differences in hostility are related to different patterns of BP during sleep and the early morning hours, a period of the day that has been associated with an increased risk of cardiovascular incidents. The data also suggest the need for further study of the significance of hostility and other personality traits and the relationship of these traits to the mechanisms of the morning surge and the risk of cardiovascular events.
The internal symmetry crossing matrices for an arbitrary compact group

Abstract The general properties of the internal symmetry crossing matrices are derived for an arbitrary compact internal symmetry group. Special emphasis is placed on the definition of these matrices and on the interpretation of the reduced amplitudes which they relate. The relation between the crossing matrices and the Racah coefficients in the particular case of SU2 is also discussed.
Diffusion through polymeric solids undergoing large deformations

AbstractThe intention of this overview is to review the literature on the diffusion of liquids through polymers that are undergoing large deformations, and to discuss the difficulties associated with modelling such a process. The inadequacy of simple equations such as Fick's equation or Darcy's equation to describe the problem with regard to characterising the stresses and strains in the polymer through which the liquid is diffusing, and the change in its material properties during swelling and the need for an alternate approach are discussed. Finally, the problem of swelling is studied within the context of the theory of mixtures and it is shown that such an approach is very well suited for the analysis of the problem.
Evaluation of the nephrotoxicity of iproplatin (CHIP) in comparison to cisplatin by the measurement of urinary enzymes.

Levels of three enzymes, leucine aminopeptidase (LAP), N-acetyl-β-D-glucosaminidase (NAG), and β-glucuronidase (BGA) were measured in the urine of patients receiving hematologically toxic doses of iproplatin (a) with or (b) without pretreatment hydration. The maximum post-treatment increases in the levels of each of the enzymes were compared between these two groups of patients. In addition, the maximum increases in urinary enzyme levels in iproplatin-treated patients were compared with those in patients treated with 40 mg/m2 cisplatin, a known nephrotoxic agent.
β-Styryl- and β-Aryl-β-alanine Products of Phenylalanine Aminomutase Catalysis

The substrate specificity of a Taxus-derived phenylalanine aminomutase (PAM) was investigated, and the enzyme was found to catalyze the conversion of variously substituted vinyl- and aryl-S-α-alanines to corresponding β-amino acids. This study shows the broad substrate specificity of PAM and thus demonstrates a potential, practical biosynthetic route toward unnatural β-amino acid subunits of Taxol analogues and β-peptides.
Evolution of porosity and geochemistry in Marcellus Formation black shale during weathering

Abstract Soils developed on the Oatka Creek member of the Marcellus Formation in Huntingdon, Pennsylvania were analyzed to understand the evolution of black shale matrix porosity and the associated changes in elemental and mineralogical composition during infiltration of water into organic-rich shale. Making the reasonable assumption that soil erosion rates are the same as those measured in a nearby location on a less organic-rich shale, we suggest that soil production rates have on average been faster for this black shale compared to the gray shale in similar climate settings. This difference is attributed to differences in composition: both shales are dominantly quartz, illite, and chlorite, but the Oatka Creek member at this location has more organic matter (1.25 wt.% organic carbon in rock fragments recovered from the bottom of the auger cores and nearby outcrops) and accessory pyrite. During weathering, the extremely low-porosity bedrock slowly disaggregates into shale chips with intergranular pores and fractures. Some of these pores are either filled with organic matter or air-filled but remain unconnected, and thus inaccessible to water. Based on weathering bedrock/soil profiles, disintegration is initiated with oxidation of pyrite and organic matter, which increases the overall porosity and most importantly allows water penetration. Water infiltration exposes fresh surface area and thus promotes dissolution of plagioclase and clays. As these dissolution reactions proceed, the porosity in the deepest shale chips recovered from the soil decrease from 9 to 7% while kaolinite and Fe oxyhydroxides precipitate. Eventually, near the land surface, mineral precipitation is outcompeted by dissolution or particle loss of illite and chlorite and porosity in shale chips increases to 20%. As imaged by computed tomographic analysis, weathering causes i) greater porosity, ii) greater average length of connected pores, and iii) a more branched pore network compared to the unweathered sample. This work highlights the impact of shale–water–O 2 interactions in near-surface environments: (1) black shale weathering is important for global carbon cycles as previously buried organic matter is quickly oxidized; and (2) black shales weather more quickly than less organic- and sulfide-rich shales, leading to high porosity and mineral surface areas exposed for clay weathering. The fast rates of shale gas exploitation that are ongoing in Pennsylvania, Texas and other regions in the United States may furthermore lead to release of metals to the environment if reactions between water and black shale are accelerated by gas development activities in the subsurface just as they are by low-temperature processes in our field study.
Atmospheric effect on classification of finite fields

The atmospheric effect on the upward radiance of sunlight scattered from the earth-atmosphere system is strongly influenced by the contrasts between fields and their sizes. In this paper, the radiances above finite fields are computed to simulate radiances measured by a satellite. A simulation case including 11 agricultural fields and four natural fields (water, soil, savanah, and forest) is used to test the effect of field size, background reflectance, and optical thickness of the atmosphere on the classification accuracy. For a given atmospheric turbidity, the atmospheric effect on classification of surface features may be much stronger for nonuniform surfaces than for uniform surfaces. Therefore, the classification accuracy of agricultural fields and urban areas is dependent not only on the optical characteristics of the atmosphere, but also on the size of the surface elements to be classified and their contrasts. It is concluded that new atmospheric correction methods, which take into account the finite size of the fields, are needed.
Genetic analysis of three loci homologous to human G9a: evidence for linkage of a class III gene with the chicken MHC

Summary The cDNA clones of two newly discovered genes in the class III region of the human major histocompatibility complex (MHC) were hybridized to chicken DNA. One of these cDNA clones (pG9a-4C7), which detects the single-copy human G9a (BAT8) gene, gave a repeatable restriction pattern. This heterologous cDNA clone was used to detect and map three different PstI restriction fragment length polymorphisms among the two internationally recognized chicken reference populations. Two of the loci were unlinked to previously mapped markers, but one polymorphism cosegregated with the EaB locus in the Compton mapping population. These results provide evidence that some genes of the mammalian class III region, such as G9a, may be linked to the MHC in chickens.
Cellular mechanisms of paired electrical stimulation in ferret ventricular myocardium: relationship between myocardial force and stimulus interval change

The subcellular mechanisms of twitch-force potentiation with paired electrical stimulation was studied in ferret ventricular myocardium using the bioluminescent calcium indicator aequorin. It is demonstrated for the first time that interpolation of an extrasystole in a train of conditioned twitches results in a beat-to-beat change in [Ca2+]i and force. Steady-state twitch force and Ca2+i were increased with paired stimulation. Increased [Ca2+]o in the setting of paired stimulation resulted in an increase in the amplitude of the postextrasystole and associated Ca2+ transient. Verapamil, a Ca2+ channel antagonist, had the opposite effect of increased [Ca2+]o. Postextrasystole potentiation was still present, but diminished in amplitude. These results indicate that postextrasystole potentiation is in part due to a verapamil-depletable store (Ca2+). Postextrasystole potentiation is therefore predominantly dependent on sarcoplasmic reticulum (SR) Ca2+ loading. Ryanodine, an alkaloid which induces Ca2+ leakage from the SR, abolished postextrasystole potentiation; however, in the presence of ryanodine the extrasystole was potentiated. Caffeine, a phosphodiesterase inhibitor which induces SR Ca2+ release and impairs uptake, also abolished postextrasystole potentiation. As with ryanodine there was resultant potentiation of the extrasystole. In the case of caffeine the calcium transient consisted of a second slow component associated with extrasystole twitch potentiation. The results are consistent with sarcolemmal Ca2+ influx playing a role in potentiation of the extrasystole in the presence of an impaired SR. These data indicate that transsarcolemmal Ca2+ influx in the presence of impaired intracellular Ca2+ buffering can directly activate the myofilaments in agreement with reports on human myocardium.
Revisions of Mid Urethral Slings Can be Accomplished in the Office

Purpose: Mid urethral slings occasionally require revision for obstructive voiding symptoms or vaginal extrusion. Our approach has been to offer revision in office or resection done under local anesthesia when the patient is agreeable and deemed an appropriate candidate. The results and complications of these procedures are presented.Materials and Methods: We retrospectively reviewed the charts of patients from January 2003 to October 2010 to determine the subset with mid urethral sling insertion who subsequently underwent revision in the office or operating room, as identified through the Northwestern Medical Enterprise Data Warehouse. The CPT code for female sling insertion (57288) or revision/removal (57287) was used.Results: A total of 41 revisions were performed in 28 of the 118 patients (23.7%) who underwent synthetic sling insertion. Reasons for adjustment were an intravesical sling (1 operating room case), extruded vaginal mesh (7 operating room and 19 office) and obstructive voiding symptoms (7 o...
A framework for predicting service delivery efforts using IT infrastructure-to-incident correlation

Predicting IT infrastructure performance under varying conditions, e.g., the addition of a new server or increased transaction loads, has become a typical IT management exercise. However, within a service delivery context, enterprise clients are demanding predictive analytics that outline future “costs” associated with changing conditions. The service delivery staffing costs incurred in addressing problems and requests (arriving in the form of incident and other problem tickets) in the managed environment is especially of high importance. This paper describes an analytical study addressing such cost prediction. Specifically, a novel approach is described in which support vector regression is used to predict service delivery workloads (measured by ticket volumes) based on managed server characteristics Additionally, a proposed framework combining various analytical models is proposed to predict service delivery staffing requirements under changing IT infrastructure characteristics and conditions. Detailed descriptions of the workload prediction techniques, as well as an evaluation using data from an actual large service delivery engagement, are presented.
Atomic Bethe-Goldstone Calculation of the Hyperfine Structure of Li ( 2 P 2 )

A variational formulation of Brueckner's theory has been applied to the calculation of hyperfine parameters for the $2^{2}P$ excited state of atomic lithium. The hierarchy of $n$th-order (or $n$-particle) Bethe-Goldstone equations defined previously has been modified so that complete electronic configurations occur at each level of the hierarchy. Thus ${\stackrel{\ensuremath{\rightarrow}}{\mathrm{L}}}^{2}$, ${\stackrel{\ensuremath{\rightarrow}}{\mathrm{S}}}^{2}$ eigenfunctions could be used throughout the calculations, although for practical reasons such functions are not explicitly constructed. Each net increment of any mean-value electronic property defined within the hierarchy is shown to be equivalent to a sum, to infinite order, of a certain well-defined set of linked diagrams in the many-particle perturbation theory. Computed results are in excellent agreement (within roughly 1%) with experimental data and with a previously published accurate perturbation calculation.
Community crime prevention: A review and synthesis of the literature

In the absence of effective formal means for controlling crime in the Western world, community crime prevention has emerged as a major alternative and supplement to the criminal justice system. This article attempts to review what is known currently about the nature, extent, and effectiveness of community-based efforts to prevent residential crime. Included in this assessment are citizen actions to protect themselves, their property, and their neighborhood, as well as efforts to prevent crime through changes in the physical environmental and through innovations in community policing. The historical, theoretical, and empirical rationale for community crime prevention strategies are discussed, but primary attention is given to the results of evaluation research in the field. Although community-based efforts are supported widely by theory, studies of natural covariation, and by numerous poorly designed evaluations, there is a paucity of strong demonstrations and evaluations showing that such interventions ca...
Effect of dietary lipids on levels of UDP-glucuronosyltransferase in liver

Abstract Others have shown recently that dietary fish oil protects against acetaminophen-induced liver injury in vivo . Fish oil was protective because it increased the clearance of acetaminophen via glucuronidation. This work left unresolved the basis for increased rates of glucuronidation in animals fed fish oil. We therefore have determined how the amount and type of lipid in the diet affect the activity of liver microsomal UDP-glucuronosyltransferase activity. Male Wistar rats were fed a fat-free diet or isocaloric diets containing 5% corn oil, olive oil or fish oil for 4 weeks. The activity of UDP-glucuronosyltransferase was highest in rats fed fish oil and lowest in rats fed the fat-free diet. Treatment with corn oil and olive oil resulted in intermediate levels of activity. Diet-induced differences in amounts of UDP-glucuronosyltransferase were shown by immunoblotting and kinetic measurements. Treatment with fish oil resulted in a 3-fold increase in the amount of UDP-glucuronosyltransferase versus the fat-free diet. Corn oil and olive oil diets caused 2-fold increases in the amount of UDP-glucuronosyltransferase versus the fat-free diet. Fatty acid analysis of microsomal lipids showed that the fat-free diet was associated with decreased levels of arachidonic acid versus the corn oil or olive oil diets. The fish oil diet resulted in increased levels of ω-3 fatty acids versus the other diets.
Differential involvement of p38 and JNK MAP kinases in HIV-1 Tat and gp120-induced apoptosis and neurite degeneration in striatal neurons

The role of p38 and c-jun-N-terminal kinases 1/2, members of the mitogen-activated protein kinase family, in mediating the toxic effects of human immunodeficiency virus-1 transactivator of transcription (Tat) and gp120 were explored in primary mouse striatal neurons in vitro. Both Tat and gp120 caused significant increases in p38 and c-jun-N-terminal kinase mitogen-activated protein kinase phosphorylation, caspase-3 activity, neurite losses and cell death in striatal neurons. Tat-induced increases in caspase-3 activity were significantly attenuated by an inhibitor of c-jun-N-terminal kinase (anthra[1,9-cd]pyrazol-6(2H)-one), but not by an inhibitor of p38 ([4-(4-fluorophenyl)-2-(4-methylsul-finylphenyl)-5-(4-pyridyl)1 H-imidazole]), mitogen-activated protein kinase. However, despite preventing increases in caspase-3 activity, c-jun-N-terminal kinase inhibition failed to avert Tat-induced neuronal losses suggesting that the reductions in caspase-3 activity were insufficient to prevent cell death caused by Tat. Alternatively, gp120-induced increases in caspase-3 activity, neurite losses and neuronal death were prevented by p38, but not c-jun-N-terminal kinase, mitogen-activated protein kinase inhibition. Our findings suggest that gp120 induces neuronal dysfunction and death through actions at p38 mitogen-activated protein kinase, while Tat kills neurons through actions that are independent of p38 or c-jun-N-terminal kinase mitogen-activated protein kinase, or through the concurrent activation of multiple proapoptotic pathways.
A STUDY OF RADIATION PROTECTION BY SULFUR COMPOUNDS.

Abstract A group of sulfur containing compounds was investigated to determine if any of these compounds possessed antiradiation character as defined by their ability to protect plant tissue ( Lycopersicon esculentum ) from the indirect effects of gamma radiation. Those compounds contain the S-H group or that were able to generate this group in solution were found to afford excellent protection. The ability of these compounds to react with OH radicals was then determined by comparison of rate constant for a known reaction involving OH radicals with and without the compounds being present. The order of reactivity with OH radicals match the protecting order found for the radiolysis of plant tissue.
Patello-femoral complications associated with total knee arthroplasty

The patello-femoral articulation accounts for a significant number of the complications that occur after total knee replacements and which require re-operation. These include problems with stability, component wear, fracture, loosening, and osteonecrosis. With careful attention to prosthetic design and surgical technique, these complications can be minimized.
Temperature takeback in the Hood River Conservation Project

Abstract Gaps between actual and expected levels of energy savings for residential retrofit programs have led to speculation about behavioral changes (referred to as “takeback”) following residential energy efficiency improvements. This analysis reveals a small, but statistically significant increase in temperature following residential retrofits in Hood River, Oregon. On average, residential temperature levels increased 0.3°C (0.5°F) due to the efficiency improvements, with low-income and wood-heated homes having larger increases in internal temperature. In total, if this reflects behavioral changes by Hood River households, it can account for only 5% of the gap between actual and predicted levels of savings induced by the Hood River Conservation Project.
Policy Preferences Among Urban Mayors A Comparative Analysis

The purpose of this paper is to determine which of a selected number of factors in the urban environment are important in influencing the priorities and goals mayors espouse for their cities. Mayors are often deemed influential in community politics; however, little is known about what shapes their priorities. To probe this question, four goal areas—community attractiveness, economic development, aid to the disadvantaged, and government efficiency—are selected for analysis. The results—based on data from National Opinion Research Center's Permanent Community Sample—suggest that no one political or social factor in the urban environment dominates across all four goal areas, but rather that there tends to be a different "politics" at work in each goal area.