cssi/SciSciGPT-SciSciNet huggingface dataset:
Validation of a Claims-based Algorithm to Identify Pregestational Diabetes Among Pregnant Women in the United States.

BACKGROUND Identifying pregestational diabetes in pregnant women using administrative claims databases is important for studies of the safety of antidiabetic treatment in pregnancy, but limited data are available on the validity of case-identifying algorithms. The purpose of this study was to evaluate the validity of an administrative claims-based algorithm to identify pregestational diabetes. METHODS Using a cohort of pregnant women nested within the Medicaid Analytic Extract (MAX) database, we developed an algorithm to identify pregestational type 1 and type 2 diabetes, distinct from gestational diabetes. Within a single large healthcare system in the Boston area, we identified women who delivered an infant between 2000 and 2010 and were covered by Medicaid, and linked their electronic health records to their Medicaid claims within MAX. Medical records were reviewed by two physicians blinded to the algorithm classification to confirm or rule out pregestational diabetes, with disagreements resolved by discussion. We calculated positive predictive values with 95% confidence intervals using the medical record as the reference standard. RESULTS We identified 49 pregnancies classified by the claims-based algorithm as pregestational diabetes that were linked to the electronic health records and had records available for review. The PPV for any pregestational diabetes was 92% [95% confidence interval (CI) 82%, 97%], type 2 diabetes 87% (68%, 95%), and type 1 diabetes 57% (37%, 75%). CONCLUSIONS The claims-based algorithm for pregestational diabetes and type 2 diabetes performed well; however, the PPV was low for type 1 diabetes.
In-situ investigation of plasticity in a Ti-Al-V-Fe (α+β) alloy: Slip mechanisms, strain localization, and partitioning

Abstract As one of the representative characteristics of plastic deformation, microstructural plastic strain inhomogeneity has triggered a broad interest in uncovering the corresponding deformation micro-mechanisms. (α+β) titanium alloys enable fruitful mechanistic explorations of this dependency, since: (i) the plastic anisotropy of the α-phase drives distinctive dislocation gliding and/or mechanical twinning modes for plastic strain accommodation; and (ii) deformation transferability between α/β phase boundaries strongly relies on both microstructural and structural parameters. The present work carried out in a Ti-Al-V-Fe (α+β) alloy is an in-situ mechanistic study, aiming to elucidate the critical deformation micro-mechanisms that are responsible for strain localization, partitioning, as well as damage inception processes. It is revealed through statistical analysis of the in-situ strain mapping results that a moderate partitioning trend exists between α- and β-phases, and that the present alloy is characterized by the eminent strain localization bands that develop at the early stage of plastic straining. Deformation micro-mechanisms including texture-facilitated prismatic 〈 a 〉 slip activation together with the near-ideal slip transfer conditions across the α/β phase boundaries are found to be predominant in the strain localization regions. The combination of postmortem and in-situ damage analyses confirm the dominant role of these long-range strain localization bands in expediting surface cracking events.
ABI-007, nanoparticle albumin-bound paclitaxel, enhances tumor radioresponse.

Proc Amer Assoc Cancer Res, Volume 47, 2006 5439 ABI-007 is an albumin stabilized, Cremophor-free, nanoparticle formulation of paclitaxel designed to overcome insolubility of paclitaxel. The ABI-007 formulation eliminates the need for the toxic solvent Cremophor that limits the dose of paclitaxel that can be safely administered and consequently, overall drug efficacy. The aim of this study was to determine if ABI-007 showed anti-tumor efficacy against a mouse ovarian carcinoma (OCa-1) and whether it could augment the effect of radiotherapy when given in a combined chemo-radiotherapy regimen. A single cell suspension of OCa-1 tumor cells was injected intramuscularly into the hind legs of C3H mice. When tumors grew to a mean diameter of 7mm, treatment with single dose radiation of 10 Gy to the tumor-bearing leg, ABI-007 90mg/kg iv, or both were initiated. The maximum tolerable dose of paclitaxel was previously established to be 60mg/kg in this strain of mice and the dose of ABI-007 was chosen to be 1.5 times the MTD of the parent drug. ABI-007 was given prior to radiation at times ranging from 5 days to 9 h or 24 h following radiation exposure. Treatment endpoint was absolute tumor growth delay (AGD) defined as the difference in days to grow from 7-12mm in diameter between treated and untreated tumors. For groups treated with the combination of ABI-007 and radiation an enhancement factor (EF) was calculated as the ratio of the difference in days to grow from 7 to 12mm in diameter between the combination treated tumors and those treated with ABI-007 alone to the AGD of tumors treated with radiation only. Treatment groups consisted of 8-10 mice each. No drug related animal toxicity was observed at a dose of 90mg/kg iv. ABI-007 as a single agent significantly prolonged the growth delay of the OCa-1 tumor by about 2 weeks, with the untreated tumors growing to 12 mm diameter in 16 days and those treated with ABI-007 in 31 days. ABI-007 was slightly more effective as a single agent than a single dose of 10 Gy radiation. The data clearly show that ABI-007 when given at any time up to 5 days before radiation produced a supra-additive anti-tumor effect. At short inter-treatment intervals of 9-24 h the EF was about 1.3, increased to a maximum EF of 2.5 at inter-treatment intervals of 2-3 days, and then decreased to an EF of 1.8 at 4 days, and 1.5 at 5 days. When ABI-007 was given after radiation, the combined anti-tumor treatment effect was less than additive. Thus, ABI-007 possesses single agent anti-tumor activity against this ovarian tumor and greatly augments the effect of radiotherapy in a time dependent manner. As we have previously demonstrated for paclitaxel and docetaxel, enhanced treatment effects of the two agents are likely the result of multiple mechanisms with a cell cycle related mechanism (G2/M arrest) controlling the short inter-treatment intervals and tumor re-oxygenation being the dominate mechanism when the treatments are separated by several days (Semin Radiat Oncol 9 (Supp 1): 2-26,1999).
WE-EF-210-07: Development of a Minimally Invasive Photo Acoustic Imaging System for Early Prostate Cancer Detection

Purpose: The objective of this work is to design, implement and characterize a catheter-based ultrasound/photoacoustic imaging probe for early-diagnosis of prostate cancer and to aid in image-guided radiation therapy. Methods: The need to image across 6–10cm of tissue to image the whole prostate gland limits the resolution achievable with a transrectal ultrasound approach. In contrast, the urethra bisects the prostate gland, providing a minimally invasive pathway for deploying a high resolution ultrasound transducer. Utilizing a high-frequency (20MHz) ultrasound/photoacoustic probe, high-resolution structural and molecular imaging of the prostate tissue is possible. A custom 3D printed probe containing a high-frequency single-element ultrasound transducer is utilized. The diameter of the probe is designed to fit inside a Foley catheter and the probe is rotated around the central axis to achieve a circular B-scan. A custom ultrasound amplifier and receiver was set up to trigger the ultrasound pulse transmission and record the reflected signal. The reconstructed images were compared to images generated by traditional 5 MHz ultrasound transducers. Results: The preliminary results using the high-frequency ultrasound probe show that it is possible to resolve finely detailed information in a prostate tissue phantom that was not achievable with previous low-frequency ultrasound systems. Preliminary ultrasound imaging was performed on tissue mimicking phantom and sensitivity and signal-to-noise ratio of the catheter was measured. Conclusion: In order to achieve non-invasive, high-resolution, structural and molecular imaging for early-diagnosis and image-guided radiation therapy of the prostate tissue, a transurethral catheter was designed. Structural/molecular imaging using ultrasound/photoacoustic of the prostate tissue will allow for localization of hyper vascularized areas for early-stage prostate cancer diagnosis.
A Feedback Theory of Two-Degree-of-Freedom Optimal Wiener-Hopf Design

The design of linear two-degree-of-freedom stabilizing controllers in a quadratic-cost setting is treated. The class of all such controllers which give finite cost is established and the trade-off possible between optimum performance, tracking-cost sensitivity, and stability margins is discussed.
History of nutrition: history and current status of research in human energy metabolism.

Research on carbon metabolism began in France with the work of Antoine Lavoisier whose discovery that carbon was oxidized in the body as it is in a burning flame led to quantitative studies that com pared CO2 production with heat production. Since that time the physics and chemistry of carbon metab olism have been a major focus in the field of nutri tion. Lavoisier penetrated the curtain of "dephlogisticated air" and began the era of quantitative chemistry. He coined the word "oxygen" (1).
Accountability: Fundamental to Democracy

This paper defends a new and aggressive version of the agency model of accountability. It argues that officials and representatives in a democracy have an obligation to make available to citizens full information about what they have been doing. It is not permissible for them to sit back and see if the citizens can find out for themselves what they have been doing, any more than such a posture would be admissible in a commercial agent such as a realtor or an accountant. The paper also does several other things: (1) it develops a contrast between agent-accountability and forensic-accountability; (2) it distinguishes between political uses of "agency" and political uses of "trust" in political theory; (3) it develops a layered account of the principals in the democratic relation of agent-accountability, rejecting the reidentification of "the people"; (4) it develops an account of the relation between accountability and elections, emphasizing that elections play an important role in the fair settlement among principals as to how they should deal with their agents; (5) it shows that Burkeian representation is not incompatible with agent-accountability; and (6) it uses the notion of agent-accountability to illuminate the distinction between non-democratic and democratic republics.
Ethical issues in mentoring adults in higher education

This chapter examines practical problems encountered in mentoring adult learners in higher education through stories of ethical dilemmas.
A concurrent search structure

Abstract The sibling trie is a highly concurrent dynamic search structure. It supports search, update, insertion, and deletion. The sibling trie is designed to minimize “hot spots” in highly concurrent shared memory environments. The main novelty of this data structure is that searches can start from any node. As a result, many alternate routes are provided to each datum, and the bottleneck of a single root node is avoided. Search time is logarithmic (regardless of the starting point), and storage is proportional to the number of data items and independent of the number of processes that access the data structure.
Comparative ester hydrolysis of carbaryl and ethiofencarb in four mammalian species

Abstract The comparative ester hydrolysis and selective toxicity of carbamate insecticides were studied in four mammalian species. Hydrolysis rates of carbaryl and ethiofencarb (Croneton) were examined in the rat, mouse, guinea pig, and gerbil. Respiratory 14 CO 2 resulting from the hydrolysis of orally administered [ carbonyl - 14 C]carbamates (0.2 mg/kg) was taken as measure of in vivo hydrolytic capabilities. Ester hydrolysis was found to be greater for ethiofencarb than for carbaryl in all species tested, although the relative order of hydrolysis among species was the same with both compounds. After 24 hr, gerbils had hydrolyzed 91% of the ethiofencarb and 65% of the carbaryl. Guinea pigs hydrolyzed somewhat less of the compounds, 65 and 58%, but considerably more than rats and mice, about 40 and 25%. Comparing hydrolysis capabilities to acute toxicity data revealed that those species exhibiting the greatest hydrolysis were equally or more susceptible to carbamate poisoning than those having lesser hydrolytic capabilities. While ester hydrolysis destroys the anticholinesterase activity of carbamates, it is clear from these findings that factors other than hydrolysis are largely responsible for the variation in toxicity of the carbamates to different mammalian species.
Do Economists Recognize an Opportunity Cost When They See One? A Dismal Performance from the Dismal Science

One expects people with graduate training in economics to have a deeper understanding of economic processes and reasoning than people without such training. However, as others have noted over the past 25 years, modern graduate education may emphasize mathematics and technique to the detriment of economic reasoning. One of the most important contributions economics has to offer as a discipline is the understanding of opportunity cost and how to apply this concept to all forms of decision making. We examine how PhD economists answer an introductory economics textbook question that requires identifying the relevant opportunity cost of an action. The results are not consistent with our expectation that graduate training leads to a deeper understanding of the concept. We explore the implications of our results for the relevance of economists in policy, research, and teaching.
Hyperemesis gravidarum: pregnancy outcomes and complications among women nutritionally supported with and without parenteral therapy

Abstract Objective: To evaluate the outcomes and complications of pregnancy experienced by women with hyperemesis, comparing those who were supported with parenteral therapy with those who were not. Methods: The medical records of patients with a diagnosis of hyperemesis gravidarum (ICD-9 code 643) admitted to Crouse Hospital, Syracuse, NY, a tertiary obstetric center for the Central New York region, between January 1995 and December 1998 were reviewed. A total of 166 patients were identified and a total of 192 admissions were reviewed. Information was gathered for age, gestational age, gravity and parity, marital status, length of stay, and number of admissions. Medical evaluation included a review of liver and thyroid function and assessment of hydration, weight loss, pregnancy complications and outcomes, and prescription for parenteral therapy. Patient identity was completely protected, and no attempt at contact with the patients or physicians caring for them was made. Results: Of the cases reviewed, 16.3% (27/166) were treated with parenteral therapy. The parenteral therapy versus no parenteral therapy groups were similar in age; parity; marital status; gestational age at hospitalization; assessment of liver, thyroid, and hydration status; and pregnancy outcome. The parenteral therapy group was noted to have longer hospitalizations with an increased incidence of complications, including venous thrombosis, cellulitis, line sepsis, bacterial endocarditis, and pneumonia. Conclusion: For this group of patients retrospectively reviewed, the objective findings and outcomes for patients treated for hyperemesis gravidarum were similar. Among patients treated with parenteral therapy, however, there appears to be a marked increase in serious complications. These data suggest that great care should be taken to assess the need for parenteral therapy in patients with hyperemesis gravidarum and that greater consideration should be given to less invasive methods of nutritional support.
Characteristics of the in vivo RBC: Plasma lithium ratio in a clinical setting

Rybakowski J, Potok E, Strzyzewski W, Chlopocka WM (1983): The effects of lithium treatment on cation transport process in erythrocytes of patients with affective illness. Pol J Pharmacol Pharm 35:209-215. Sapru MK, Geetha H, Shetty KT (1987): A single reagent method of phosphate estimation in phosphatase(s) assay. Ind. J Biochem Biophys 24:340343. Sanui H (1974): Measurement of inorganic orthophosphate in bioiogic~ materials: extraction properties of butyl acetate. Anal Biorhem ~:489-5~. Sengupta N, Datta SC, Sengupta D, Bal S (1980): Platelet and erythrocyte membrane adenosine triBIOL PSYCHIATRY 537 1989;26:533-537
Hepatic encephalopathy in a pregnant mare: identification of histopathological changes in the brain of a mare and fetus.

An 11-year-old Thoroughbred broodmare was evaluated for suspected hepatic dysfunction. Clinical signs of hepatic encephalopathy were evident at admission. Hepatic ultra-sonographic evaluation revealed an increase in hepatic size, rounded borders and normal echogenicity. There was no evidence of cholelithiasis or bile duct distention. Increased activity of hepatic enzymes, increased bile acid and bilirubin concentration and an increased ammonia concentration were supportive of a diagnosis of hepatic disease and hepatic encephalopathy. Histopathological evaluation of a liver biopsy specimen was consistent with chronic active hepatitis. The mare was treated with intravenous fluids and antimicrobials, pentoxyfilline, branched-chain amino acids and dietary manipulation. Clinical improvement was observed initially, however, 3 weeks later, deterioration in the mare's condition necessitated euthanasia. Pathological lesions at necropsy were restricted to the liver and brain. The liver was diffusely firm with a prominent reticular pattern on the cut surface. A large choledocholith was present in the main bile duct of the left liver lobe. Histopathological examination of the liver revealed severe fibrosis, with hyperplastic bile ducts and mononuclear and neutrophilic inflammation. Pathological changes consistent with hepatic encephalopathy, (Alzheimer type II cells), were evident in the cerebrum of both the mare and the fetus.
Intrinsic fibroblast-mediated remodeling of damaged collagenous matrices in vivo.

Abstract Numerous studies have examined wound healing and tissue repair after a complete tissue rupture and reported provisional matrix and scar tissue formation in the injury gap. The initial phases of the repair are largely mediated by the coagulation response and a principally extrinsic inflammatory response followed by type III collagen deposition to form scar tissue that may be later remodeled. In this study, we examine subfailure (Grade II sprain) damage to collagenous matrices in which no gross tissue gap is present and a localized concentration of provisional matrix or scar tissue does not form. This results in extracellular matrix remodeling that relies heavily upon type I collagen, and associated proteoglycans, and less heavily on type III scar tissue collagen. For instance, following subfailure tissue damage, collagen I and III expression was suppressed after 1 day, but by day 7 expression of both genes was significantly increased over controls, with collagen I expression significantly larger than type III expression. Concurrent with increased collagen expression were significantly increased expression of the collagen fibrillogenesis supporting proteoglycans fibromodulin, lumican, decorin, the large aggregating proteoglycan versican, and proteases cathepsin K and L. Interestingly, this remodeling process appears intrinsic with little or no inflammation response as damaged tissues show no changes in macrophage or neutrophils levels following injury and expression of the inflammatory markers, tumor necrosis factor-α and tartrate-resistant acid phosphatase were unchanged. Hence, since inflammation plays a large role in wound healing by inducing cell migration and proliferation, and controlling extracellular matrix scar formation, its absence leaves fibroblasts to principally direct tissue remodeling. Therefore, following a Grade II subfailure injury to the collagen matrix, we conclude that tissue remodeling is fibroblast-mediated and occurs without scar tissue formation, but instead with type I collagen fibrillogenesis to repair the tissue. As such, this system provides unique insight into acute tissue damage and offers a potentially powerful model to examine fibroblast behavior.
Clinical images in medical toxicology: heroin overdose with non-cardiogenic pulmonary edema.

A 23-year-old female presented to the emergency department (ED) after a reported intravenous heroin overdose. Last seen two hours prior to EMS arrival, she was found apneic, pulseless and cool. Two...
Methanandamide increases COX-2 expression and tumor growth in murine lung cancer

SPECIFIC AIMThe ability of methanandamide to modulate murine lung cancer growth was evaluated. We investigated the involvement of the cannabinoid receptors and methanandamide-mediated increased COX-2 and PGE2 production in the observed increased tumor growth.PRINCIPAL FINDINGS1. Systemic methanandamide administration increases tumor growthWe have previously shown that systemic THC treatment suppresses the immune response to implanted tumors, resulting in increased tumor growth via CB2 receptor signaling. Because endogenous ligands for the cannabinoid receptors are widely distributed and are elevated in prostate, bladder, and colon carcinoma tissues, we were prompted to determine the effect of endocannabinoids on tumor growth in vivo. We evaluated the effect of methanandamide administration (5 mg/kg, i.p. four times per week) on tumorigenicity in murine lung cancer. We found a significant enhancement of tumor growth in methanandamide-treated mice compared with diluent-treated controls (n=9, P<0.01).2. Meth...
Preventing cardiovascular disease in the 21st century: therapeutic and preventive implications of current evidence.

Cardiovascular disease (CVD), particularly coronary heart disease (CHD), remains a major cause of mortality, morbidity, and disability in the US and other Westernized societies. As a result of therapeutic and preventive measures to control the CVD/CHD epidemic, mortality has declined steadily during the last several decades with a consequent gain in life expectancy, but the 1990s witnessed a slowing of this decline. In response to these trends, a range of therapeutic regimens were developed to address adverse CVD risk factor levels and their deleterious effects. The scientific evidence regarding the efficacy, cost effectiveness, strengths, and limitations of a range of pharmacologic and lifestyle approaches to CVD prevention — both primary and secondary — are reviewed in depth. Clinical trials aimed at primary and secondary prevention of CVD have documented the efficacy and cost effectiveness of various drugs in lowering individual risk factor levels and in reducing clinical CVD events. More recently, the idea of a ‘polypill’ containing low doses of multiple drugs has generated much interest, with proponents arguing that, given the high prevalence of CVD risk factors and the effectiveness of pharmacologic interventions, such a drug combination would reduce CHD mortality by 88% if taken by all individuals aged α55 years. However, current treatments to control high BP and serum cholesterol, while effective, do not typically reduce morbidity and mortality to levels observed in low-risk individuals, i.e. those with favorable levels of all readily measured major risk factors. Rather, primary prevention of all major risk factors starting early in life is critical. Prospective population-based research has delineated multiple long-term benefits associated with low-risk status in young adulthood and middle age, i.e. markedly lower age-specific CVD and total mortality rates, increased life expectancy, lower healthcare costs, lower medication use and prevalence of chronic diseases, and higher self-reported quality of life at older ages. Unfortunately, despite declines in the prevalence of most major CVD risk factors, low-risk status remains rare among US adults. Data have also demonstrated that adverse levels of one or more major risk factors precede clinical CHD in 90% or more of all cases, undermining the assertion that major CVD risk factors account for ‘no more than 50%’ of CHD cases. Hence, while numerous treatment options exist for secondary prevention of CVD, strategies that focus on progressively increasing the proportion of low-risk individuals could greatly reduce the need for secondary prevention in the first place. Public health policies must focus on prevention of all major risk factors simultaneously, using lifestyle approaches from early ages onwards to reduce population CVD risk to endemic levels, rather than current epidemic levels.
Grid-free density-functional technique with analytical energy gradients.

We have implemented a completely analytical linear combination of atomic orbitals-X\ensuremath{\alpha} local density-functional method with exact energy gradients. The superiority of the analytical method over the corresponding grid-based technique in terms of speed, smooth energy surfaces, and accurate gradients is demonstrated in calculations for the umbrella inversion mode of ammonia. The equilibrium geometry and inversion barrier height are also shown to compare well to experimental data.
Storage and the electricity forward premium

We develop and test a model describing the influence of natural gas storage inventories on the electricity forward premium. The model is constructed by linking the effect of gas storage constraints on the higher moments of the distribution of electricity prices to an established model of the effect of those moments on the forward premium. The model predicts a sharply negative effect of gas storage inventories on the electricity forward premium when demand for electricity is high and space-heating demand for gas is low. Empirical results, based on PJM data, strongly support the model.
Unenhanced Raman scattering from pyridine chemisorbed on a stepped silver surface: Implications for proposed sers mechanisms

Abstract In an effort to separate chemical from electromagnetic sources of enhancement in surface-enhanced Raman scattering, we have investigated the adsorption
Dominance-diversity relationships of the free amino acids in coastal zooplankton

Abstract 1. 1. Free amino acid composition is examined in six copepod species occurring along a salinity gradient that extends from the open ocean to fresh water. 2. 2. Salinity accounts for half of the variation in total concentration. The remainder results from seasonal temperature change and associated variables. 3. 3. Going from a marine species, through a series of three estuarine species, and finally to a fresh water representative, the basic amino acids become more important, whereas glycine, alanine and taurine decrease. The result is a comparatively uniform pattern of composition in fresh water. This relationship is expresed by an index of biochemical dominance.
Melasma: A comprehensive update: Part I

Melasma is a common disorder of hyperpigmentation affecting millions of people worldwide. While it is thought to be triggered or exacerbated by sun exposure and hormones, much remains to be understood about its pathogenesis. A thorough understanding of the etiology of melasma and the research tools available to study this condition are crucial to enhancing management and developing novel targeted therapies of this often frustrating condition.
Are Written Reports of Suicide and Seeking Help Contagious? High Schoolers' Perceptions1

To assess contagion for suicide and seeking mental health help, 128 high school students read a short vignette about a teen under stress. Half of them were told that this teen knew someone in the community who had similar problems and had committed suicide, and half were told that the teen knew someone in the community who had similar problems and had sought help from a mental health professional. A 2 (Gender of Respondent) x 2 (Gender of Victim) x 2 (Vignette: Response to Stress) analysis of variance indicated a significant main effect for response, and a significant two-way interaction for gender of respondent and response to stress. These high school students thought contagion occurred for suicide as well as seeking mental health help. Girls tended to be more responsive to seeking help, whereas boys were slightly more responsive to suicide. An implication is that publicity about seeking help may ameliorate suicidal contagion.
Near-isothermal conditions in the middle and lower crust induced by melt migration

Simple one-dimensional thermal models that include the effects of melt migration have been developed. The models show that long-lived plutonism results in a quasi-steady-state geotherm with a rapid temperature increase in the upper crust and nearly isothermal conditions in the middle and lower crust. The thermal structure of the crust strongly influences deformation, metamorphism and plutonism1,2,3. Models for the geothermal gradient in stable crust predict a steady increase of temperature with depth. This thermal structure, however, is incompatible with observations from high-temperature metamorphic terranes exhumed in orogens1,4,5,6. Global compilations7 of peak conditions in high-temperature metamorphic terranes define relatively narrow ranges of peak temperatures over a wide range in pressure, for both isothermal decompression and isobaric cooling paths. Here we develop simple one-dimensional thermal models that include the effects of melt migration. These models show that long-lived plutonism results in a quasi-steady-state geotherm with a rapid temperature increase in the upper crust and nearly isothermal conditions in the middle and lower crust. The models also predict that the upward advection of heat by melt generates granulite facies metamorphism, and widespread andalusite–sillimanite metamorphism in the upper crust. Once the quasi-steady-state thermal profile is reached, the middle and lower crust are greatly weakened due to high temperatures and anatectic conditions, thus setting the stage for gravitational collapse8, exhumation and isothermal decompression after the onset of plutonism. Near-isothermal conditions in the middle and lower crust result from the thermal buffering effect of dehydration melting reactions that, in part, control the shape of the geotherm.
ETHNIC DIFFERENTIATION BY BLOCKS WITHIN CENSUS TRACTS

How common is ethnic differentiation within census tracts and what types of tracts are most likely to exhibit this tendency? This research attempts to answer these questions with block data from the 1990 U.S. census for Los Angeles County. We measured non-random unevenness in ethnic percentage within tracts for twelve ethnic populations by means of an adjusted index of dissimilarity. Of the total of 300 sampled tracts, 48% showed statistically significant differentiation at the block level. Census tracts frequently mask details of ethnic patterning, especially in transition zones between larger ethnic settlement regiorrs. Ethnic differentiation was most clearly related to block variations in housing type and cost, and tracts with fairly uniform housing were much less likely to show significant internal differentiation. Block-level differentiation was no greater for blacks than for some Asian groups and was average or low for non-Hispanic whites and people of Mexican origin. Although the census tract has been by far the most convenient and widely used areal unit for analyzing the geography of metropolitan areas, it may mask the intricacies of ethnic distributions and be less homogeneous internally than is perhaps assumed. In this research we investigate intra-tract variations in ethnic percentages. We attempt to answer three related questions: (1) To what extent do blocks within census tracts show greater variation in ethnic group percentages than could be expected from random influences? (2) Which ethnic populations and types of tracts show the greatest ethnic differentiation by block? (3) Within tracts showing high levels of ethnic differentiation, are details of ethnic patterning associated with characteristics of specific blocks? For simplicity of expression we use the word "ethnic" to include social groups defined by either race or national origin, "Latino" to refer to the Mexican-origin population, and "white" to mean non-Hispanic whites. Knowing the extent of intra-tract differentiation in ethnic composition would seem to be basic to understanding both ethnic distributions and the detailed spatial structure of contemporary urban areas. However, recent research has not examined such patterns within tracts. Micro-level research in geography has not been sufficiently detailed in terms of place or neighborhood to shed light on these matters. In macro- level research, the numerous studies of residential differentiation in metropolitan areas, most frequently using factorial ecology or measuring residential segregation, have almost always employed census tracts themselves as the basic areal units-thus begging the question of the internal homogeneity of tracts. Sociologists have mea- sured black-white segregation at the block level for many years (eg, Taeuber and Tdeuber, 1963, and one recent study examined the effect of parcel-size variations on city rankings of relative segregation, demonstrating that the areal unit of measure- ment can have a substantial effect (Lasus and Falk, 1990).
X-ray absorption near-edge spectra of overdoped La 2 − x Sr x CuO 4 high- T c superconductors

We present results for realistic modeling of the x-ray absorption near edge structure (XANES) of the overdoped high-${T}_{c}$ superconductor ${\mathrm{La}}_{2\ensuremath{-}x}{\mathrm{Sr}}_{x}{\mathrm{CuO}}_{4}$ in the hole doping range $x=0.20$ \ensuremath{-} 0.30. Our computations are based on a real-space Green's function approach in which strong-correlation effects are taken into account in terms of a doping-dependent self-energy. The predicted O K-edge XANES is found to be in good accord with the corresponding experimental results in this overdoped regime. We find that the low energy spectra are dominated by the contribution of O atoms in the cuprate planes, with little contribution from apical O atoms.
Absorption of ultra-intense laser pulses.

We use simulations to investigate the interaction of ultra-intense laser pulses with a plasma. With an intensity greater than ${10}^{18}$ W/${\mathrm{cm}}^{2}$, these pulses have a pressure greater than ${10}^{3}$ M bar and drive the plasma relativistically. Hole boring by the light beam is a key feature of the interaction. We find substantial absorption into heated electrons with a characteristic temperature of order the pondermotive potential. Other effects include a dependence on the polarization of the incident light, strong magnetic field generation, and a period of intense instability generation in the underdense plasma.
Individual intake of free-choice mineral mix by grazing beef cows may be less than typical formulation assumptions and form of selenium in mineral mix affects blood Se concentrations of cows and their suckling calves.

The objectives of this study were to determine (1) the individual ad libitum intake of mineral mix by beef cows managed under a year-long, fall-calving, forage-based production regimen and (2) if Se form in the mineral mix affected the blood Se concentrations of cows and suckling calves. Twenty-four late-gestation (6 to 8 months) Angus-cross cows (2.7 ± 0.8 years; body weight [BW] = 585 ± 58 kg) were blocked by BW and randomly assigned (n = 8) to a mineral supplement treatment (TRT) containing 35 ppm Se as either inorganic (ISe; sodium selenite), organic (OSe; Sel-Plex®), or a 1:1 combination of ISe/OSe (MIX). Cows commonly grazed a 10.1-ha predominately tall fescue pasture and had individual ad libitum access to TRT using in-pasture Calan gates. Cows calved from August to November and calves had common ad libitum access to creep feed and a mineral supplement that lacked Se. Cow jugular blood was taken at 28-day intervals (13 periods) and calf blood was taken with cows from birth through weaning. Individual cow mineral mix (mean = 54.0 ± 7.0 g/day, range = 97.3 to 27.9 ± 7.4 g/day) and Se (mean = 1.82 ± 0.25 mg/day, range = 3.31 to 0.95 ± 0.25 mg/day) intakes were affected by period (P 0.30). Cow blood Se (0.109 to 0.229 ± 0.01 μg/mL) was affected (P < 0.002) by period, Se form, and their interaction, with ISe < MIX for periods 8 and 11, ISe < OSe for all periods except period 1, and MIX < OSe for periods 2 to 4, 7, 8, 10, and 12. Calf blood Se (in micrograms Se per milliliter) was correlated with cow blood Se and affected (P < 0.0001) by cow Se TRT, with ISe (0.07 to 0.11) < MIX (0.10 to 0.15) = OSe (0.16 to 0.19). These data reveal that (1) mean supplemental ad libitum cow mineral intake was 36 % less than the typical formulation intake expectations (85 g/day) and, correspondingly, mean supplemental Se intake was 33 % less than that allowed by the FDA and (2) cow Se TRT differentially affected both cow and calf blood Se concentrations, resulting in adequate concentrations for all cows but inadequate concentrations for ISe calves.
Race, Class, and Neighborhood: Differences in the Residential Return on Individual Resources

Using individual-level data from the neighborhood files of the 1970 Public Use Sample, the components of individual socioeconomic status (SES) education, occupation, and income-are treated as resources; and racial differences in the return on these resources, differences in neighborhood residential quality, are estimated, decomposed, and subjected to component analysis. It is documented that blacks receive a lesser return than whites; they reside in inferior neighborhoods despite similar resources. The notion is tested and supported that one mechanism explaining the lesser return is that blacks are channeled into predominantly black neighborhoods and are thus less able than whites to achieve class segregation. Channeling has a greater impact on economic factors than on social factors; on the latter, intraracial segregation seems more possible. As a final note, given the theoretical importance of community and neighborhood contexts, and thegeneral assumption in stratification theory that individual status (or parental status) is an adequate proxy for such context, a reexamination of studies of racial differences previously presumed to be net of class is suggested. The persistence of residential segregation by race has been demonstrated on many occasions (Erbe; Kantrowitz), and it has been shown to persist independent of occupational segregation and other forms of economic segregation (Duncan and Duncan; Kantrowitz; Simkus; Taeuber; Taeuber and Taeuber). Most recently, Simkus has demonstrated that up to one-fourth of occupational residential segregation can be attributed to racial segregation in both the occupational and residential distributions, and he redemonstrated the point that within-occupation residential racial segregation is extremely high. Using detailed tract level data from one SMSA, Erbe found that black professionals and managers, black college graduates, and blacks with incomes in excess of $25,000 lived in tracts comparable, respectively, to those of whites who were unskilled workers, school dropouts, and earned less than $3,000. Others have examined the effects of residential socioeconomic segregation, both structural effects (e.g., Morgan; Smith)
Anaplastic large cell lymphoma of the spleen

A case is presented of CD30+ anaplastic large cell lymphoma of the spleen. The patient, a 61 year old woman with a history of chronic lymphocytic leukemia (CLL) was seen for the sudden development of splenomegaly with thrombocytopenia. A splenectomy was performed which showed massive replacement of the spleen by a population of large atypical lymphoid cells showing bizarre nuclear forms and multinucleated tumor cells reminiscent of Reed-Sternberg cells. Immunohistochemical studies showed strong membrane and dot-like paranuclear positivity in the majority of the atypical cells for CD30, with coexpression in many of the cells for CD15. Additionally, the cells also strongly reacted with CD3, UCHL-1, EMA and LCA. The present case illustrates an unusual variant of anaplastic (CD30+) large cell lymphoma sharing histologic and immunophenotypic features that overlap with those of Hodgkin's disease. The history in this patient of CLL with sudden development of splenomegaly raises the possibility of transformation of CLL into a high-grade lymphoma (Richter's syndrome). The possible pathogenetic implications of this phenomenon are discussed.
A stochastic analysis of the tree paradigm

Abstract The tree paradigm, which is a problem in optimal stopping, has important ramifications for human capital acquisition, search behavior, firm entry, and in the theory of renewable resources. Our paper extends previous work in the stochastic literature on several fronts. We exhibit a tractable solution to the rotation problem for the stochastic model, analyze the effects of inputs which control the growth process, and illustrate our results with a multi-stage learning problem.
A Note on Professor Solow's Growth Model

In the February 1956 issue of this Journal, Robert M. Solow presented an ingeniously simple yet extremely useful model for the examination of various aspects of the problem of economic growth.1 It does not seem to be generally realized, however, that this model, after a minor change, may be used to make sense out of the assertions that: (a) a large initial dose of investment may be required before an underdeveloped country can overcome existing barriers to growth; (b) it may pay to adopt capital-intensive production methods even if they appear to be "noneconomic"; (c) in contrast to (a) above, something very like spontaneous combustion sometimes occurs, i.e., for no apparent reason the growth process becomes self-perpetuating. This feature of the model may be used as an important element in an explanation of "the industrial revolution." To proceed with the argument, let me first reproduce Solow's equation (6): r = sF(r,1) nr
Backward and simultaneous masking measured in children with language-learning impairments who received intervention with Fast ForWord or Laureate Learning Systems software.

The developers of a computer-assisted language intervention program called Fast ForWord (FFW) have claimed that their software changes temporal processing abilities as a result of specialized modif...
Comparison of two methods for circumventing the Coulomb divergence in supercell calculations for charged point defects

Density-functional-theory calculations were performed for the unrelaxed $+2$ Si vacancy and $+2$ self-interstitial utilizing periodic boundary conditions and two different methods---the uniform background charge method and the local moment counter charge method---for circumventing the divergence of the Coulomb potential. Formation energies in nominal 64-, 216-, 512-, 1000-, and 1728-atom supercells were converged with respect to Brillouin zone sampling and then extrapolated to an infinite sized supercell by fitting to a polynomial in odd powers of $1∕L$ where $L$ is the cubed root of the supercell volume. The extrapolated values from the two methods agreed very well ($2\phantom{\rule{0.3em}{0ex}}\mathrm{meV}$ difference for the vacancy and $13\phantom{\rule{0.3em}{0ex}}\mathrm{meV}$ difference for the interstitial) as expected from inspection of their respective energy expressions. The extrapolated values and fitting parameters were then employed to evaluate analytic correction formulas that have been proposed to remove spurious electrostatic contributions from defect formation energies. The results indicate that existing formulas are not capable of removing these contributions and that further development is needed in this area.
The Thermoregulatory Function of Diel Vertical Migration for a Juvenile Fish, Cottus extensus

Juvenile sculpin (Cottus extensus) less than 30 mm long exhibit a diel vertical migration in the limnetic zone of Bear Lake (Utah-Idaho). Using mid-water and bottom trawls we found that these fish inhabit the bottom of the lake (5° C) during the day but migrate 30–40 m into the water column at night where they reside in the metalimnion or epilimnion at temperatures near 13–16°C. Larger fish do not migrate into the water column. Stomach analyses demonstrated that the young-of-the-year fish do not migrate into the water column to feed: from July to October their diet is 70–93% benthic ostracods and copepods, and pelagic prey are rarely consumed. Furthermore, gut fullness of the sculpin increases through the daylight period and decreases through the night, reaching minimum levels just before the dawn descent. Laboratory experiments demonstrated that the diel migration would increase digestion rate from 3%/h at profundal temperatures, to 22%/h in the warmer surface water, thus allowing the fish to empty their guts overnight and permit feeding the following day. Additionally, sculpin held in a temperature and feeding regime that mimicked that experienced by migrating fish grew 300% faster than those reared at 5° C. Given the overwhelming importance of fast growth for juvenile fishes, a post-feeding thermotaxs that increases digestion may be a common phenomenon increasing growth, and affecting the distribution and bioenergetic relationships of fish.
Sensitivity and tolerance to autonomic effects of ethanol in adolescent and adult rats during repeated vapor inhalation sessions.

: Background: It is during adolescence that most drinkers initiate ethanol intake, with some of this use being excessive. One possible contributor to the increased ethanol consumption often seen during adolescence in humans and in various animal models is age differences in ethanol sensitivity and tolerance. The present study examined the impact of age on ethanol-related alterations in the autonomic nervous system Methods: Sensitivity to the initial ethanol challenge and chronic tolerance as well as acute and protracted withdrawal-like phenomena were assessed in male adolescent and adult Sprague-Dawley rats, using implanted telemetry probes with ethanol delivered via vapor inhalation Results: Both ages showed similar ethanol-induced tachycardia and activity suppression; however, adolescents were found to be more sensitive than adults to the hypothermic effect of ethanol, data opposite other results from our laboratory and elsewhere using intragastric intubations or intraperitoneal administrations of ethanol. Although little tolerance to ethanol's tachycardic or activity suppressant effects was seen after repeated ethanol inhalation sessions, chronic tolerance to ethanol's hypothermic effect developed faster in adults than in adolescents. A withdrawal-like syndrome, characterized by bradycardia and hypoactivity, typically emerged during the dark phase of the diurnal cycle after ethanol vapor exposure sessions. These effects were observed in animals of both ages, with the bradycardic effect more pronounced in adolescents Conclusions: In contrast to results indicating that adolescents may be less sensitive than adults to ethanol's hypothermic effect when ethanol is administered via bolus injection/intubation, adolescents appear more sensitive and develop tolerance to ethanol's hypothermic effects more slowly than adults when ethanol is administered at a more moderate rate via vapor inhalation