cssi/SciSciGPT-SciSciNet huggingface dataset:
Two-stage examinations: Can examinations be more formative experiences?:

Two-stage examinations consist of a first stage in which students work individually as they typically do in examinations (stage 1), followed by a second stage in which they work in groups to comple...
Kupffer Cells Survive Plasmodium berghei Sporozoite Exposure and Respond with a Rapid Cytokine Release.

The liver stage of the Plasmodium life cycle features sporozoite traversal of the liver sinusoidal barrier through Kupffer cells (KCs) followed by invasion of hepatocytes. Little is known about the interaction of Plasmodium sporozoites with KCs, the liver-resident macrophages. Previous reports suggest KCs do not mount a pro-inflammatory response and undergo cell death following this interaction. Our work explores this interaction using primary rat KCs (PRKCs) and Plasmodium berghei sporozoites. We analyzed PRKC culture supernatants for markers of an immunological response through cytokine arrays. Additionally, cell wounding and death were assessed by monitoring lactate dehydrogenase (LDH) levels in these supernatants and by live/dead cell imaging. We found that PRKCs mount an immunological response to P. berghei sporozoites by releasing a diverse set of both pro- and anti-inflammatory cytokines, including IFNγ, IL-12p70, Mip-3α, IL-2, RANTES, IL-1α, IL-4, IL-5, IL-13, EPO, VEGF, IL-7, and IL-17α. We also observed no difference in LDH level or live/dead staining upon sporozoite exposure, suggesting that the KCs are not deeply wounded or dying. Overall, our data suggest that sporozoites may be actively modulating the KC’s reaction to their presence and altering the way the innate immune system is triggered by KCs.
Neurocognitive impairment is worse in HIV/HCV-coinfected individuals with liver dysfunction

Infections with HIV and hepatitis C virus (HCV) can individually and jointly contribute to neurocognitive impairment (NCI). Rates of NCI in HIV/HCV-coinfected persons range from 40 to 63% but its correlates have not been described. In this study, we examined HIV/HCV-coinfected adults on antiretroviral therapy (ART) with undetectable HIV RNA in blood (n = 412) who were assessed using a comprehensive neuropsychological test battery. Demographics, host and viral biomarkers, and markers of liver dysfunction were compared between impaired (n = 198) and unimpaired (n = 214) participants using logistic regression. The cohort was predominantly middle-aged men, half of whom (48%) had NCI. The odds of NCI increased by almost two-fold when serum albumin was 50 IU/L, and 2.2-fold with every unit increase in log10 AST to Platelet Ratio Index (APRI). These readily available clinical biomarkers of NCI measure hepatic injury and/or dysfunction, suggesting a mechanism for the effects of HCV infection on NCI. They may identify patients at increased risk of NCI who could be prioritized for early initiation of HCV treatment to protect or improve cognition.
Cryo-EM structures of alpha-synuclein fibrils with the H50Q hereditary mutation reveal new polymorphs

Deposits of amyloid fibrils of alpha synuclein are the histological hallmarks of Parkinsons disease, multiple system atrophy, and dementia with Lewy bodies. Although most cases of these diseases are sporadic, autosomal dominant hereditary mutations have been linked to Parkinsons disease and dementia with Lewy bodies. Seeing the changes to the structure of amyloid fibrils bearing these mutations may help to understand these diseases. To this end, we determined the cryoEM structures of alpha synuclein fibrils containing the H50Q hereditary mutation. We find that the H50Q mutation results in two new polymorphs of alpha synuclein, which we term Narrow and Wide Fibrils. Both polymorphs recapitulate the conserved kernel formed by residues 50 to 77 observed in wild type structures; however, the Narrow and Wide Fibrils reveal that H50Q disrupts a key interaction between H50 and E57 on the opposing protofilament, abolishing the extensive protofilament interface formed by preNAC residues in the wild type rod structure. Instead, the Narrow Fibril is formed from a single protofilament and the two protofilaments of the Wide protofilament are held together by only a pair of atoms, the C gamma atoms from the two threonine 59 sidechains. Further, we find that H50Q forms an intramolecular hydrogen bond with K45 leading to the formation of a novel beta arch formed by residues 36 to 46 that features an extensive hydrogen bond network between Y39, T44, and E46. The structures of the H50Q polymorphs help to rationalize the faster aggregation kinetics, higher seeding capacity in biosensor cells, and greater cytotoxicity we observe for H50Q compared to wild type alpha synuclein.
Quantification of Solute Topology in Atom Probe Tomography Data: Application to the Microstructure of a Proton-Irradiated Alloy 625

The analysis of solute clustering in atom probe tomography (APT) has almost exclusively relied on a simple algorithm based on the simple friend-of-friend analysis where a threshold distance or maximum separation defines whether atoms are part of a cluster or part of the matrix. This method is however limited to very specific microstructures and is very sensitive to parameter selection. To expand the range and applicability of current APT analysis tools, we introduce new quantitative data analysis methods based on density-based hierarchical clustering algorithms and relevant to solute clustering and segregation. We demonstrate the methods’ performance on the complex microstructure developing in a proton-irradiated Alloy 625, specifically focusing on the analyses of nanoscale Al clusters, Si clusters, and Si-decorated dislocation loops.
Skill-biased technical change again? Estimating the effect of TaskRabbit on local employment in the housekeeping industry

The rise of gig platforms brings new opportunities and challenges to local labor markets: they may complement offline workers by facilitating service matching and creating jobs for them, or they may substitute offline workers by intensifying the competition among them. Drawing on Skill-Biased Technical Change and digital platforms theory, we study the impacts of gig platforms on local employment in the housekeeping industry. Exploiting the staggered expansion pattern of TaskRabbit (a gig platform that matches freelance labor to local demand for everyday tasks) into US counties at different times, we identify its impact on the housekeeping industry. Our difference-in-differences estimate shows a disproportionate decrease in full-time housekeeping employment in TaskRabbit-operated areas. The decline is mainly driven by cognitive (middle-skilled) workers (i.e., managers) instead of manual (low-skilled) workers (i.e., janitors). Additional evidence, however, implies that gig platforms may not crowd out workers but rather they incubate local entrepreneurship through additional self-employment. Implications for platform design, policy, and research are discussed.
Elucidating the role of electrophoretic mobility for increasing yield in the electrophoretic deposition of nanomaterials

Abstract Hypothesis Catalysts, chemical, gas, and bio- sensing devices fabricated from porous nanoparticle films show better performance and sensitivity than their bulk material counterparts because of their high specific surface area. Electrophoretic deposition (EPD) technique is a cost-effective, fast, versatile, and easy to perform method to fabricate porous nanoparticle films. However, conventional EPD is currently limited by the fact that the deposition rate decreases with time, resulting in an eventual plateau in the deposit yield. Here, we sought to overcome this limitation by establishing and leveraging the critical role of the particle’s electrophoretic mobility in EPD kinetics. Experiments To identify the impact of electrophoretic mobility on EPD yield we used alumina nanoparticles suspended in ethanol as a model system. Changes in particle mobility were monitored via changes in the effective pH (pHe) of the suspension during EPD. We also developed a new suspension replenish EPD approach that allows us to maintain near-constant particle mobility and particle concentration with time thereby increasing yield. Findings We observed that in conventional EPD the particle mobility of the alumina nanoparticles decreased with time, resulting in a halting of deposition. Further, using the suspension replenish EPD, we observed a linear increase in the mass of the deposited film with time, overcoming the plateau limitation of conventional EPD.
NONPARAMETRIC FILTERING OF THE REALIZED SPOT VOLATILITY: A KERNEL-BASED APPROACH

A kernel weighted version of the standard realized integrated volatility estimator is proposed. By different choices of the kernel and bandwidth, the measure allows us to focus on specific characteristics of the volatility process. In particular, as the bandwidth vanishes, an estimator of the realized spot volatility is obtained. We denote this the filtered spot volatility. We show consistency and asymptotic normality of the kernel smoothed realized volatility and the filtered spot volatility. We consider boundary issues and propose two methods to handle these. The choice of bandwidth is discussed and data-driven selection methods are proposed. A simulation study examines the finite sample properties of the estimators.
Cooling of Windings in Electric Machines via 3-D Printed Heat Exchanger

This article presents a novel use of three-dimensional printed direct winding heat exchangers (3-D-DWHX) to improve the thermal management of the stator in high power density electric machines. The 3-D-DWHX is in direct contact with the stator windings, enabling high continuous current densities. The use of dielectric polymer for the heat exchanger allows direct contact with the windings without an additional insulation material. By occupying the otherwise unused space between double layer concentrated windings, there is no significant impact on the electromagnetic design, and a smaller machine can be realized. The result is an increased continuous power rating and power density of electric machines. The polycarbonate-aluminum flake 3-D-DWHX was validated in a nonencapsulated motorette test, achieving a continuous current density of 20.4 ARMS/mm2 for a hotspot temperature of 148 °C. Finite element analysis shows that the same design, when encapsulated, can achieve 33.3 ARMS/mm2 current density with a hotspot temperature of 195 °C, corresponding to a continuous specific power of 11.8 kW/kg.
The Evolving Role of Metastasectomy for Patients with Metastatic Renal Cell Carcinoma

Surgical metastasectomy continues to be utilized for patients with solitary or low-volume metastatic renal cell carcinoma (mRCC). Although few high-quality data are available to evaluate outcomes, local treatment is recommended when feasible because it may allow a subset of patients to delay or avoid systemic treatments. With the development of improved mRCC therapies, utilization of metastasectomy has increased because most patients have incomplete responses to systemic treatment of their metastases. This review discusses the rationale and history of metastasectomy, trends in utilization, prognostic factors for patient selection, site-specific considerations, alternatives for nonsurgical local treatment, and risk of morbidity associated with metastasectomy.
Multivariate prediction of dementia in Parkinson's disease.

Cognitive impairment in Parkinson’s disease (PD) is pervasive with potentially devastating effects. Identification of those at risk for cognitive decline is vital to identify and implement appropriate interventions. Robust multivariate approaches, including fixed-effect, mixed-effect, and multitask learning models, were used to study associations between biological, clinical, and cognitive factors and for predicting cognitive status longitudinally in a well-characterized prevalent PD cohort (n = 827). Age, disease duration, sex, and GBA status were the primary biological factors associated with cognitive status and progression to dementia. Specific cognitive tests were better predictors of subsequent cognitive status for cognitively unimpaired and dementia groups. However, these models could not accurately predict future mild cognitive impairment (PD-MCI). Data collected from a large PD cohort thus revealed the primary biological and cognitive factors associated with dementia, and provide clinicians with data to aid in the identification of risk for dementia. Sex differences and their potential relationship to genetic status are also discussed.
Analysis of the ODE model equations

Abstract The features of the 4 × 4 (four ordinary differential equations (ODEs) in four unknowns) model of Chapter 1 are determined by the right hand side (RHS) terms of the ODEs, which sum to give the left hand side (LHS) derivatives in time, t. In this chapter, the main program of Chapter 1 for the numerical integration of the four ODEs is extended to compute the RHS and LHS terms of the ODEs, which are displayed numerically and plotted. With this detailed analysis of the ODE terms, the properties of the ODE solutions are elucidated and explained. In particular, terms that are dominant are identified as the main source of the ODE solution features.
Social Media Happiness Expression Through the Virtual Reality: Cultural Differences on Instagram

The social media happiness expression through the virtual reality analyzes Instagram photographic data to identify factors predictive of happiness from the Western and the Eastern cultures. The emotional expressions (photographs), hashtags (words), demographics (gender, age, and locations), and pose (head tilt, body turn, posture) were used as factors to detect an individual’s various happiness expression. This research observed the patterns of the photographic dataset to discover the universal happiness expression today through social media, in particular Instagram. We integrated the computational methods from image processing and machine learning to obtain practical psychological indicators from photographic data. We observed one’s perception of happiness was significantly influenced by the communication methods both photographic and hashtags data as well as their own culture through social media. This research centralized disparate archives of happiness expressions with photographic data from Instagram using a theoretical, artistic, and quantitative methods. The photographic data and written data are in the process of compiling into divergent visualization as a Virtual Reality, which will provide users the opportunity to identify the thought-provoking patterns and navigate the photographic data and written data at the extensive perspective from an individual perspective. This research addresses the representation of one’s social media image with the pressure on the external viewpoint and creates an interactive platform of the direct comparison in diverse social and cultural contexts of happiness expression on social media.
Demographic Assessment of Mono(2-ethylhexyl) Phthalate (MEHP) and Monoethyl Phthalate (MEP) Concentrations in Common Bottlenose Dolphins (Tursiops truncatus) From Sarasota Bay, FL, USA.

Common bottlenose dolphins (Tursiops truncatus) have previously demonstrated exposure to phthalate esters. Phthalates and phthalate esters are commonly added to consumer goods to enhance desirable properties. As the amount of plastic marine debris increases, these chemicals can easily leach from these products into the surrounding environment. To evaluate demographic variability in exposure, eight phthalate metabolites were quantified in urine samples collected from free-ranging bottlenose dolphins sampled in Sarasota Bay, FL, USA (2010-2019; n = 51). Approximately 75% of individual dolphins had detectable concentrations of at least one phthalate metabolite. The most frequently detected metabolites were mono(2-ethylhexyl) phthalate (MEHP; n = 28; GM = 4.57 ng/mL; 95% CI = 2.37-8.80; KM mean = 7.95; s.d. = 15.88) and monoethyl phthalate (MEP; GM = 4.51 ng/mL; 95% CI = 2.77-7.34; ROS mean = 2.24; s.d. = 5.58). Urinary concentrations of MEHP and MEP were not significantly different between sex (MEHP p = 0.09; MEP p = 0.22) or age class (i.e., calf/juvenile vs. adult; MEHP p = 0.67; MEP p = 0.13). Additionally, there were no significant group differences in the likelihood of MEHP or MEP detection for any demographic as determined by a Peto-Peto test. Frequency of detection was similar for both metabolites between males and females (MEHP p = 0.10; MEP p = 0.40) as well as between juveniles and adults (MEHP p = 0.50; MEP: p = 0.60). These findings suggest ubiquitous exposure risk for both sexes and age classes, warranting further investigation into potential sources and health implications.
Goldenhar Syndrome With Ankylosis of the Temporomandibular Joint: A Case Report

Goldenhar syndrome, or oculoauriculovertebral dysplasia, represents approximately 10% of craniofacial microsomia anomalies. These patients have a variety of clinical features that are relevant to anesthesia providers, including a high-arched palate, mandibular hypoplasia, micrognathia, and temporomandibular joint (TMJ) malformation. The oral manifestations of Goldenhar syndrome range from malocclusion to complex TMJ involvement. Outside of the dental and oral surgery literature, the potential for TMJ ankylosis in Goldenhar patients is seldom emphasized. TMJ ankylosis impacts airway management, and anesthesia providers must be aware of this clinical phenotype when planning the anesthetic care of patients with Goldenhar syndrome.
Comparing Motivations for Including Enforcement in US COVID-19 State Executive Orders

The United States’ response to COVID-19 has been predominantly led by state governments. To understand if, why, and how state governments include enforcement language in their executive order respo...
The autophagy initiating kinase ULK1 is required for pancreatic cancer cell growth and survival

Amongst cancer subtypes, pancreatic ductal adenocarcinoma (PDA) has been demonstrated to be most sensitive to autophagy inhibition, which may be due to unique metabolic rewiring in these cells. The serine/threonine kinase ULK1 forms the catalytic center of a complex mediating the first biochemical step of autophagy. ULK1 directly recieves signals from mTORC1 and AMPK to trigger autophagy under stress and nutrient poor conditions. Studies in genetic engineered mouse models of cancer have revealed that deletion of core downstream autophagy genes (ATG5, ATG7) at the time of tumor iniation leads to a profound block in tumor progression leading to the development of autophagy inhibitors as cancer therapeutics. However, most preclinical studies and all clinical studies have relied on non-specific lysomotropic agents such as chloroquine and its derivatives, whose toxicity and off-target issues preclude further clinical development and which do not represent the impact of solely biochemically disrupting the autophagy pathway. Furthermore, druggable targets in the core autophagy pathway are quite limited, with ULK1 and ULK2 representing the only protein kinases in the pathway. Here we explore the genetic requirement for ULK1 and ULK2 in human PDA cancer cell lines and xenografts, and take advantage of new small molecule ULK1 inhibitors to demonstrate that ULK inhibition can overcome autophagy induction triggered by PDA therapeutics including chemotherapy and MEK inhibition. Finally we show that ULK inhibitors increase MHC Class I in PDA cells, suggestion a potential therapeutic avenue for such agents in combination with checkpoint immunotherapy.
Smoothing surface roughness using Al2O3 atomic layer deposition

Abstract Al2O3 atomic layer deposition (ALD) was used to smooth the roughness on silicon wafers obtained prior to chemical mechanical polishing (CMP). The initial silicon wafers had an average RMS surface roughness of 3.3 nm as determined by atomic force microscopy (AFM) measurements. AFM line scans also measured an average lateral spacing of ≈490 nm between the surface asperities. The RMS roughness decreased and the average lateral spacing increased progressively with number of Al2O3 ALD cycles. After 3000 Al2O3 ALD cycles that deposit an Al2O3 film thickness of 370 nm, the RMS roughness reduced to 1.5 nm and the average lateral spacing between the surface asperities increased to ≈890 nm. Additional Al2O3 ALD cycles produced little change in the RMS roughness or average lateral spacing. The efficiency of the smoothing decreased when the lateral distance between the surface asperities was much larger than the Al2O3 ALD film thickness. Power spectral density (PSD) analysis revealed that the ALD smoothing was most effective for surface topographical features with lateral spacings in the range of 10s to 100s of nanometers. Reflectivity studies of silver films deposited on the silicon wafers also demonstrated that Al2O3 ALD smoothing improved the optical performance of reflective mirrors.
A Rational Basis for Affirmative Action: A Shaky but Classical Liberal Defense

I am honored to participate in a symposium on the occasion of the 100th anniversary of one of America's preeminent law reviews. I am saddened, however, to write, at what should be a moment of celebration, with the knowledge that both the Law School and the College of Literature, Science and the Arts are enmeshed in extensive litigation over the critical and explosive issue of affirmative action. To find striking evidence of the deep split of learned judicial views on this issue, it is necessary to look no further than the sequence of opinions in Gratz v. Bollinger1 and Grutter v. Bollinger.2 Gratz was bought by a rejected white applicant to the College of Literature, Science and the Arts; Grutter by a rejected white applicant from the Law School. The two district courts reached opposite conclusions on what they perceived to be the central issue in this running dialogue: did the racial diversity of the student body count as a compelling state interest that justified a departure from the color blind norm established under the equal protection clause of the Fourteenth Amendment? Diversity, at the district court level, counted as a compelling state interest for the University of Michigan College of Literature, Science and the Arts, but not for its Law School. This division of opinion was erased when Grutter was reversed on appeal, most fittingly, by a bare five to four majority.3 No one seriously thinks that the matter will rest here, for the tensions within the Sixth Circuit and beyond make it likely that at long last the Supreme Court will revisit this issue.
Sarcomere length dependence of rat skinned cardiac myocyte mechanical properties: dependence on myosin heavy chain.

The effects of sarcomere length (SL) on sarcomeric loaded shortening velocity, power output and rates of force development were examined in rat skinned cardiac myocytes that contained either α-myosin heavy chain (α-MyHC) or β-MyHC at 12 ± 1°C. When SL was decreased from 2.3 μm to 2.0 μm submaximal isometric force decreased ∼40% in both α-MyHC and β-MyHC myocytes while peak absolute power output decreased 55% in α-MyHC myocytes and 70% in β-MyHC myocytes. After normalization for the fall in force, peak power output decreased about twice as much in β-MyHC as in α-MyHC myocytes (41%versus 20%). To determine whether the fall in normalized power was due to the lower force levels, [Ca2+] was increased at short SL to match force at long SL. Surprisingly, this led to a 32% greater peak normalized power output at short SL compared to long SL in α-MyHC myocytes, whereas in β-MyHC myocytes peak normalized power output remained depressed at short SL. The role that interfilament spacing plays in determining SL dependence of power was tested by myocyte compression at short SL. Addition of 2% dextran at short SL decreased myocyte width and increased force to levels obtained at long SL, and increased peak normalized power output to values greater than at long SL in both α-MyHC and β-MyHC myocytes. The rate constant of force development (ktr) was also measured and was not different between long and short SL at the same [Ca2+] in α-MyHC myocytes but was greater at short SL in β-MyHC myocytes. At short SL with matched force by either dextran or [Ca2+], ktr was greater than at long SL in both α-MyHC and β-MyHC myocytes. Overall, these results are consistent with the idea that an intrinsic length component increases loaded crossbridge cycling rates at short SL and β-MyHC myocytes exhibit a greater sarcomere length dependence of power output.
Friction and damping of {Xe}/{Ag(111) }

We have measured the force required to slide molecularly thin xenon films along Ag(111), and observe that the friction associated with the sliding is highly sensitive to the xenon film's lattice spacing. Our result sheds light on the relative contributions of lattice vibrations (phonons) and electronic mechanisms to the total frictional energy dissipation.
Microstructures and Interfaces in Al2O3‐−5 wt% Al CMC Synthesized by Plasma Sintering of Attrition‐Milled Precursors

Microstructure-property-processing relationships are studied for synthesized Al2O3-5 wt pct Al composites. To obtain a synthetic hierarchical metal reinforcement, a chemically active precursor with about 0.3-micron clusters is made by attrition milling, formed without binder, and rapidly consolidated in an inductively coupled plasma. Sintered composites were more than 97 percent dense. Microstructures of the composites by SEM and TEM show unusually favorable wetting, no porosity, and evidences of localized, less than 100 nm wide metal networks. Localized, 5-10-micron wide metal-rich regions consisting of submicron ceramic grains, were also revealed. At 1 kg of load, the average microhardness was 416, and crack lengths were 11 +/- 3 microns. 18 refs.
Forbidden Transitions in One- and Two-Electron Atoms

Publisher Summary The notion of forbidden decays has its roots in the Ritz combination principle and the idea that the measured frequencies of all observed spectral lines can be expressed as the difference of two term frequencies. The fact that for any system not all the possible differences of the known terms are observed initially led to a separation of the possible radiative transitions into allowed and forbidden types. The well-known selection rules for electromagnetic decay, which provide a time-tested basis for this separation, predate quantum mechanics and were originally based on classical electromagnetic theory applied to the vector model of the atom. It is now possible to make a more refined distinction between the allowed and forbidden decays, and this chapter shows what are considered the appropriate selection rules in some detail. The chapter reviews recent theoretical and experimental work on forbidden transitions in the one- and two-electron systems. The chapter also considers the characterization of the forbidden transitions and each of the known transition types.
Ground Water Recharge with Sewage Effluent

Sewage effluent is an excellent source of water for irrigation, especially in dry areas. Before it can be used for unrestricted irrigation, conventional treatment should be followed by treatment so that the water meets the agronomic, public health, and aesthetic requirements for unrestricted irrigation. This usually means reduction of nitrogen concentration to less than 10 mg/l, complete removal of pathogenic organisms, and essentially complete removal of suspended solids and biodegradable organic carbon. This can often be achieved with a groundwater recharge system, using the soil and aquifer materials as natural filters. Studies on two experimental projects in Phoenix showed that “soil-aquifer treatment” systems can reduce nitrogen concentrations from about 20 mg/l to about 7 mg/l, fecal coliform concentrations from about 3500 per 100 ml (chlorinated secondary effluent) to 0.3 per 100 ml, viruses from 21 plaque-forming units/l to 0, suspended solids from 15 mg/l to 1 mg/l, and total organic carbon from 20 mg/l to 3 mg/l. The latter represents mostly the nondegradable carbon. Hydraulic loading rates for sands to loamy sands were about 300 ft/yr. Thus, 1 acre of infiltration basin can renovate about 300 af/year of sewage effluent. The renovated water should be removed from the aquifer to avoid its spread into high-quality native groundwater.(Please note that af/year stands for acre feet/year.)
Life and the Need for a Solvent

Life as we know it consists of chemical interactions that take place in the liquid state, yet the requirement that life be liquid-based is not normally part of anyone’s definition of a living system. Thus, we cannot state categorically that life in either a solid or gaseous state is impossible. There are, however, compelling theoretical advantages for the complex chemical interactions that compose the living state to occur in a liquid medium. These include (1) an environment that allows for the stability of some chemical bonds to maintain macromolecular structure, while (2) promoting the dissolution of other chemical bonds with sufficient ease to enable frequent chemical interchange and energy transformations from one molecular state to another; (3) the ability to dissolve many solutes while enabling some macromolecules to resist dissolution, thereby providing boundaries, surfaces, interfaces, and stereochemical stability; (4) a density sufficient to maintain critical concentrations of reactants and constrain their dispersal; (5) a medium that provides both an upper and lower limit to the temperatures and pressures at which biochemical reactions operate, thereby funneling the evolution of metabolic pathways into a narrower range optimized for multiple interactions; and (6) a buffer against environmental fluctuations.
Paracas Art and Architecture: Object and Context in South Coastal Peru

Paracas Art and Architecture: Object and Context In South Coastal Peru. Edited by Anne Paul. iowa City: University of Iowa Press, 1991.445 pp., map, figures, b/w illustrations, references, index. $29.95 (cloth).
Estimation of myocardial blood flow for longitudinal studies with 13N-labeled ammonia and positron emission tomography

Although several modeling strategies have been developed and validated for quantification of myocardial blood flow (MBF) from 13N-labeled ammonia positron emission tomographic data, a comparison of noise characteristics of the various techniques in serial studies is lacking. Dynamic 13N-labeled ammonia positron emission tomographic imaging was performed at baseline and after pharmacologic stress in (1) single studies of four dogs with concomitant measurement of microsphere blood flow and (2) initial and follow-up studies of eight normal volunteers. Data were obtained from short-axis images for the blood pool and myocardial regions corresponding to the three arterial vascular territories. Indexes of MBF were obtained by four distinct techniques: (1) University of California, Los Angeles, twocompartment model, (2) Michigan two-compartment model, and (3) a one-compartment model with variable blood volume term. Coronary flow reserve (CFR) was measured as the ratio of stress/rest MBF. The estimated standard deviation of the measurement error for the relative change between studies of rest and stress MBF and CFR was determined for each technique. Estimates of MBF from all techniques showed good correlation with microsphere blood flow (r=0.95 to 0.96) in canine myocardium. In human studies, similar mean estimates of MBF were found with all techniques. Techniques 1 and 3 showed the smallest interstudy variability in MBF and CFR. The estimated standard deviations for these techniques were approximately 20%, 30%, and 27% for rest MBF, stress MBF, and CFR, respectively. Noninvasive quantification of MBF and CFR from dynamic 13N-labeled ammonia positron emission tomography is most reproducible with technique 1 or 3. The ability to account for differences in myocardial partial volume gives preference to technique 3. However, substantial interstudy variability in regional MBF remains, suggesting the importance of procedural factors or real temporal fluctuations in MBF.
Application and comparison of on-line identification methods for flexible manipulator control

The application of on-line identification schemes to flexible manipulators is considered. The common objective of all methods, for control purposes, is a time domain parameterization of the system transfer function. Time domain methods generally require more computational load, are more sensitive to noise than frequency domain methods, and suffer from over- (under-) parameterization of the transfer function. Frequency domain methods parameterize the lightly damped transfer function in terms of its easily recognizable poles and zeros and offer alternatives to time domain methods. Several solutions to overcome the aforementioned problems are discussed and demonstrated through experimental studies on a one-link flexible manipulator.
Physical properties of chondrules in different chondrite groups: Implications for multiple melting events in dusty environments

Chondrite groups (CV, CK, CR) with large average chondrule sizes have low proportions of RP plus C chondrules, high proportions of enveloping compound chondrules, high proportions of chondrules with (thick) igneous rims, and relatively low proportions of type-I chondrules containing sulfide. In contrast, chondrite groups (CM, CO, OC, R, EH, EL) with smaller average chondrule sizes have the opposite properties. Equilibrated CK chondrites have plagioclase with relatively low Na; equilibrated OC, R, EH and EL chondrites have more sodic plagioclase. Enveloping compound chondrules and chondrules with igneous rims formed during a remelting event after the primary chondrule was incorporated into a dustball. Repeated episodes of remelting after chondrules were surrounded by dust would tend to produce large chondrules. RP and C chondrules formed by complete melting of their precursor assemblages; remelting of RP and C chondrules surrounded by dust would tend to produce porphyritic chondrules as small dust particles mixed with the melt, providing nuclei for crystallizing phenocrysts. This process would tend to diminish the numbers of RP and C chondrules. Correlations among these chondrule physical properties suggest that chondrite groups with large chondrules were typically surrounded by thick dust-rich mantles that formed in locally dusty nebular environments. Chondrules that were surrounded by thick dust mantles tended to cool more slowly because heat could not quickly radiate away. Slow cooling led to enhanced migration of sulfide to chondrule surfaces and more extensive sulfide evaporation. These chondrules also lost Na; the plagioclase that formed from equilibrated CK chondrites was thus depleted in Na.
Financial contracts, opportunism, and disclosure management

This article shows that if all variables that determine a firm's future cash flows are not contractible, it can be ex ante optimal to design a financial contract that admits debtholders waiving debt covenants on a discretionary basis and firms investing opportunistically subsequent to contracting. Further, as the contractible variable becomes less informative, the contract attaches greater significance to it. Finally, uncertainty in the magnitude of reporting latitude induces aggressive reporting by the firm to avoid violating the covenant or to enhance the chances of a waiver. The debtholders respond by sometimes not allowing the firm to implement mutually beneficial projects.
Risk factors of portal vein thrombosis in Crohn's disease patients.

Patients with inflammatory bowel disease, such as Crohn’s disease (CD), suffer from a threefold increase in the risk of venous thromboembolism. Small bowel, segmental bowel, or ileocolonic resection to treat Crohn’s disease can lead to rare complications of portal vein thrombosis (PVT), which can lead to further poor health outcomes, such as small bowel ischemia. The study attempts to find different risk factors that may be associated with postoperative complications of PVT in Crohn’s disease patients. In a 1 to 3 case–control study following Institutional Review Board approval, 13 Crohn’s disease patients with documented radiological postoperative diagnosis of PVT from 2004 to 2011 and 39 CD patients who did not have postoperative PVT were matched by retrospective chart review for patient demographics, preoperative course and workup, anticoagulant use, and operative procedure. Univariate analysis was performed to draw correlations on risk factors for the development of PVT. In the 13 CD patients with PVT, concurrent cancer, liver disease, and dyslipidemia were present in 23.1%, 23.1%, and 15.4% of the population, respectively. Compared to the 39 CD only patients, concurrent cancer, liver disease, and dyslipidemia were present in only 2.6%, 2.6%, and 0% of the population, respectively. Of the CD patients with PVT, 61.5% were on preoperative steroids compared to 28.9% of the CD only patients. PVT development in CD patients is correlated with concurrent cancer (p = 0.016), liver disease (p = 0.016), dyslipidemia (p = 0.012), and preoperative steroid usage (p = 0.036). Concurrent cancer, liver disease, dyslipidemia, and preoperative steroid usage were risk factors associated with the development of PVT in Crohn’s patients. Since there is limited literature on PVT in CD, more data needs to be collected, and additional studies should be done to further assess the prevention, diagnosis, and management of the disease.
Persistence versus Withdrawal from the College Classroom: A Test of Four Theoretically Derived Propositions.

The purpose of this study was to test the generalizability of results obtained in laboratory research in the area of persistence behavior of students who drop college courses. Four hypotheses that included predictions concerning which students were most likely to drop courses, which courses were most likely to be dropped, and at what point in the semester students were most likely to drop courses were formulated from the results of laboratory research. None of the hypotheses were adequately supported by the data, suggesting that the results of laboratory research in this area are not readily transferable to college course-dropping behavior, at least without taking into account more relevant situational and personal variables.
2-Amino-3-phosphonopropionate blocks the induction and maintenance of long-term potentiation in rat hippocampal slices.

Abstract Rat hippocampal slices were used to examine the effects of 2-amino-3-phosphonopropionate (AP3), an inhibitor of phosphatidylinositol (PI) turnover linked to metabotropic quisqualate receptors, on the development and maintenance of long-term potentiation (LTP) in area CA1. When perfused for 5 min prior to tetanization at concentrations of 100–1000 μM, d,l -AP3 had no effect on baseline synaptic transmission but blocked posttetanic potentiation (PTP) and the induction of LTP. Unlike the N- methyl- d -aspartate (NMDA) antagonists, 2-amino-5-phosphonovalerate (AP5) and MK-801, AP3 eliminated the late phase of LTP when applied immediately after tetanization. These data support the hypothesis that PI turnover is a factor in the expression and maintenance of LTP.
Laterality and visual persistence: Support for Di Lollo’s model of hemispheric symmetry

An experiment that examines Di Lollo’s claim (1981) for cortical symmetry of visible persistence effects is reported. In the present work, visible persistence is compared across the two visual fields on two types of currently popular persistence tasks and over two levels of target duration and target complexity. Although significant duration and complexity effects are obtained, no evidence for differential persistence in the hemifields is found for any set of stimulus conditions on either of the persistence tasks.
Measuring the QCD transition temperature with resonant dileptons in ultrarelativistic nuclear collisions.

We calculate the transverse-mass distribution of lepton pairs in the ${\mathrm{\ensuremath{\rho}}}^{0}$-\ensuremath{\omega} peak. We use two different ultrarelativistic nuclear collision scenarios: one with a strong first-order deconfinement phase transition, and one with a first-order chiral phase transition. In both cases, we assume thermal and chemical equilibrium throughout the collision, and consider transition temperatures in the range 150\char21{}200 MeV. We then follow the experimental procedure and fit the transverse-mass distribution with a thermal distribution. The fitting temperature is near the transition temperature for both scenarios.
Evaluation of Three Testing Methods Used to Determine Cognitive Constructs in Computer Programming

Memorization has been an often-used technique for testing cognitive construct organization by programmers. This study looks at three different memorization techniques and introduces a new method for examination of syntax and logical constructs.
Health Insurance Portability and Accountability Act: administrative simplification to understand the revised proposed privacy standards--a policy update.

Changes in health care delivery, technology, and reimbursement have expanded significantly over the past 100 years, creating a complex health care system network of services provided by multiple teams of providers and payers. The changes in health care delivery, along with increased costs, have resulted in a system that is increasingly inadequate and incapable of dealing with emerging financial, administrative, and patient care data. Our present health care system has become burdensome, cumbersome, inept, and inefficient and is unable to handle the considerable paperwork created by a complex health care system. In addition, issues created by information technology have raised serious ethical questions and concerns over who would have access to an electronic record and who “owns” the electronic record, as well as concerns regarding the privacy and confidentiality of electronic medical records. As a result, with the increasing numbers of health care networks and resource consumers, financial constraints, complexity of patient care, and inadequate management tools, coupled with technological advances, there is a need for a new and changing health care paradigm to manage the electronic records. The Health Insurance Portability and Accountability Act (HIPAA) was passed in 1996 as part of the federal government’s concern about spiraling health costs, inadequate health care management systems, and patients’ privacy. These sweeping changes in health legislation were designed to improve the efficiency and effectiveness of our health care system. As part of HIPAA, Congress recognized the concern for ethical issues and need for patient privacy standards and set a 3-year deadline to enact such protections as part of HIPAA. The law required the Department of Health and Human Services (DHHS) to adopt these protections via regulation if Congress did not address the issue in a timely manner. The purpose of this article is to globally review the provisions of HIPAA and to discuss in detail the modifications and revisions to the privacy rule better known as the Standards for Privacy of Individually Identifiable Health Information. The privacy rule covers health plans, health care clearinghouses, and those health care providers who conduct financial and administration transactions electronically. This article will alert providers regarding the “relaxed” and more flexible interpretation of the unintended rigid and structured guidelines created under the Clinton administration.
Microbially Mediated Biodegradation of Hexahydro-1,3,5-Trinitro-1,3,5- Triazine by Extracellular Electron Shuttling Compounds

The potential for humic substances to stimulate the reduction of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) was investigated. This study describes a novel approach for the remediation of RDX-contaminated environments using microbially mediated electron shuttling. Incubations without cells demonstrated that reduced AQDS transfers electrons directly to RDX, which was reduced without significant accumulation of the nitroso intermediates. Three times as much reduced AQDS (molar basis) was needed to completely reduce RDX. The rate and extent of RDX reduction differed greatly among electron shuttle/acceptor amendments for resting cell suspensions of Geobacter metallireducens and G. sulfurreducens with acetate as the sole electron donor. AQDS and purified humic substances stimulated the fastest rate of RDX reduction. The nitroso metabolites did not significantly accumulate in the presence of AQDS or humic substances. RDX reduction in the presence of poorly crystalline Fe(III) was relatively slow and metabolites transiently accumulated. However, adding humic substances or AQDS to Fe(III)-containing incubations increased the reduction rates. Cells of G. metallireducens alone reduced RDX; however, the rate of RDX reduction was slow relative to AQDS-amended incubations. These data suggest that extracellular electron shuttle-mediated RDX transformation is not organism specific but rather is catalyzed by multiple Fe(III)- and humic-reducing species. Electron shuttle-mediated RDX reduction may eventually become a rapid and effective cleanup strategy in both Fe(III)-rich and Fe(III)-poor environments.
The Arabs in Israel: Some Observations on the Psychology of the System of Controls

This study uses the case of Israeli Arabs to analyze the impact of the system of controls in creating psychological quiescence in a subordinate minority. A theoretical framework, which accounts for both the aggregate process of ethnic political behavior and reduces the ethnic phenomenon to individual terms, is used. It provides a systematic insight into the way in which the attitudes of the minority are manipulated in order to subordinate them to the requirements of the superordinate majority. The three dimensions that are most pertinent to understanding the attitudinal prerequisites for creating quiescence are the degree of perceptual consensus, intracommunal consensus, and intercommunal conflict. The empirical analysis indicates that the system of controls to which the Israeli Arabs have been subjected may have lowered the level of both their perceptual consensus and intracommunal consensus. This, in turn, might have decreased the amount of inter-communal conflict between the Arabs and the Jews, thus sp...
Classroom Structuring Methods and Strategies for Children and Youth with Autism Spectrum Disorders

Autism experts and individuals with high-functioning autism contend that many individuals with autism spectrum disorders (ASDs) respond most favorably to information that is presented visually. Accordingly, strategies capitalizing on this visual preference have received significant recent attention in both ASD research and practitioner-related literature. This article provides a review of visually based strategies for organizing classrooms for children and youth with ASD. Classroom structuring methods, visual schedules, and visually based organizational strategies are described and discussed. For each of the above, a justification, a brief review of the research literature, implementation guidelines, recommendations for effective use, and suggested resources for practitioners are provided. Tables and figures that provide examples of methods are also provided.
Identification of NGF receptor in chromatin of melanoma cells using monoclonal antibody to cell surface NGF receptor

A 230 KDa species of Nerve Growth Factor (NGF) receptor was immunoprecipitated from EcoRI-digested chromatin of melanoma cells using a monoclonal antibody to the 75 KDa cell surface NGF receptor. The chromatin NGF receptor was shown to exist tightly bound to DNase II-sensitive sequences which, upon growth factor binding, became resistant to DNase II digestion.