cssi/SciSciGPT-SciSciNet huggingface dataset:
Association of previous cardiac surgery with outcomes in left ventricular assist device patients.

Objectives History of prior cardiac surgery has traditionally been considered a risk factor for subsequent cardiac procedures. The aim of this study was to investigate the outcomes of patients implanted with a left ventricular assist device via redo sternotomy. Methods Prospectively collected data were reviewed for all patients implanted with a continuous-flow left ventricular assist device at a single institution from December 2006 through June 2018. Patients were separated into 2 cohorts: those with a history of prior cardiac surgery (redo sternotomy) and those undergoing primary sternotomy at the time of left ventricular assist device implantation. The primary outcome was overall survival. Results Of the 321 patients included in the study, 77 (24%) were implanted via redo sternotomy and 244 (76%) via primary sternotomy. The redo sternotomy cohort was generally older (59 ± 10 vs 57 ± 12 years, P = 0.050) and had a higher incidence of ischaemic disease (70% vs 49%, P = 0.002). The Kaplan-Meier survival analysis demonstrated that overall survival was not significantly different between the redo sternotomy and primary sternotomy groups (6-month survival: 86% vs 92%; 5-year survival: 53% vs 51%; log-rank P = 0.590 for overall difference during follow-up). The propensity score analysis consistently showed that redo sternotomy was not significantly associated with mortality risk (hazard ratio 1.19, 95% confidence interval 0.73-1.93; P = 0.488). Redo sternotomy patients were more likely to require rehospitalization during their first year postoperatively (P = 0.020) and spent less time out of the hospital during the first year (P = 0.046). Conclusions The redo sternotomy cohort represents a more technically challenging patient population, but overall survival similar to that of primary sternotomy patients can be achieved.
Chapter 15 – ANOVA: Testing for Differences Among Many Samples and Much More

In this chapter, you will learn how the analysis of variance produces a p-value based on an F test based on the F statistic, a ratio of two variance measures, to perform each hypothesis test. The numerator represents the variability due to the special, interesting effect being tested (for example, differences from one group to another) and the denominator represents a baseline measure of randomness (because we see differences even within a group). If the ratio is larger than the value in the critical F value, the effect is significant. The one-way analysis of variance, in particular, is used to test whether or not the averages from several independent situations are significantly different from one another. This is the simplest kind of analysis of variance, and if the F test is significant, then individual pairs of averages may be tested against one another using the least-significant-difference test. Advanced analysis of variance (ANOVA) techniques include two-way and higher designs, in addition to covariance analysis and multivariate ANOVA. Note that the ANOVA table does not tell the whole story; always ask to see the average values so that you can understand what's really going on. Although these more complex situations require more complicated calculations, the general ANOVA idea remains the same: to test significance by comparing one source of variability (the one being tested) against another source of variability (the underlying randomness of the situation) and to produce the p-value.
Can Private Forecasters Beat the USDA? Analysis of Relative Accuracy of Crop Acreage and Production Forecasts

This study examines the accuracy of United States Department of Agriculture (USDA) crop Acreage and Production forecasts for corn, soybeans, and winter wheat relative to their private counterparts over 1970–2019. Our main findings suggest that USDA forecasts often had significantly smaller errors than their private counterparts. The accuracy of both USDA and private forecasts has improved over time, but the accuracy of USDA forecasts has improved more than that of private forecasts, maintaining the USDA’s relative accuracy advantage. The accuracy advantage of Prospective Plantings and Acreage reports highlights the importance of survey-based approaches used for these forecasts.
Multifaceted Exercise Prescription in the Management of an Overhead Athlete with Suspected Distal Biceps Tendinopathy: A Case Report.

Background and Purpose: Distal biceps brachii tendinopathy is an uncommon diagnosis. Various exercise prescriptions have demonstrated efficacy in the management of tendinopathy, although studies frequently focus on the effects of a specific type of muscular contraction (i.e., concentric, isometric, or eccentric). Currently, there is limited research guiding the conservative management of distal biceps tendinopathy, particularly with overhead athletes, and even less evidence reporting a multifaceted exercise prescription for individuals with tendinopathy. The purpose of this case report is to describe the integration of various modes of therapeutic exercise into a rehabilitation program for an overhead athlete with suspected distal biceps brachii tendinopathy. Case Description: A 19-year-old male collegiate baseball pitcher presented to an outpatient physical therapy clinic via direct access for left antecubital pain, which began 6 weeks prior to the evaluation while pitching during try-outs. Following physical examination, distal biceps tendinopathy was the likely clinical diagnosis. Interventions focused on early eccentric exercise eventually progressing to concentric and plyometric activity for return to sport. Outcomes: The patient was seen five times over the course of 4 weeks. He had significant improvements of pain, patient-reported functional outcomes, global rating of change, strength, tenderness, and provocation testing. The patient was able to return to an off-season pitching program. Discussion: An impairment-based and task-specific exercise prescription was effective for this patient with distal biceps tendinopathy. Understanding the biomechanical demands of an individual’s functional limitation, in this case baseball pitching, may assist the decision-making process and optimize outcomes. Additional research into the most effective exercise prescriptions for individuals with uncommon tendinopathies is warranted.
Would that it were so simple: Dimensions of context diversity differentially relate to four implicit interethnic associations

Published studies point to heterogeneity in the relations between context diversity and implicit associations. To rule out methodological variations as an explanation, the relations between three d...
Simplifying thryoid cancer 131I maximum permissible activity estimation

1317 Background: Prior to administering 131I for the treatment of thyroid cancer, blood samples are taken every day over several days following administration of small activities of 131I, from which total dose (D) to blood per administered mCi of 131I is estimated. 131I maximum permissible administered activity (MPAA) is derived from D so as not to exceed 200 cGy to blood. We conducted this investigation to determine whether it is possible to determine MPAA from only 3 blood samples collected over 4 days, & to evaluate whether MPAA estimates are affected by impaired renal function (IRF). Methods: Data were examined retrospectively for 121 pts (63 female pts; 58 male pts; age = 58±17 yrs), including 26 with compromised renal function (defined as pts for whom both BUN & creatinine values exceeded normal limits established by each of the laboratories that analyzed their blood samples) evaluated for MPAA before 131I treatment. On the 1st day, 3-4 mL blood was withdrawn prior to 131I administration & counted in a well counter for baseline background activity determination. Pts then were administered an activity of 37-148 MBq 131I, & the 1st sample of 3-4 mL of blood was withdrawn 4 hrs later. Blood samples were repeated at 24, 48, 72 & 96-144 hrs. At the end of all counting sessions, 1-mL aliquots of blood collected throughout the week were counted for 1 min in a well counter. Method1 computed D1 from counts measured for the 5 blood samples (J Nucl Med 2017;58:1588-95). Method2 computed the effective half-life of 131I clearance from only the 1st & last well counter measurements & the baseline blood sample; for intervening time periods exponentially interpolated counts were substituted for actual well counter measurements to estimate blood dose (D2). MPAA1 = 200 cGy/D1 & MPAA2 = 200 cGy/D2. Results: D1 was greater for pts with IRF than pts with NRF (1.08±0.37 versus 0.62 ±0.45 rad/mCi, p < 0.001), as was D2 (1.09±0.36 versus 0.65 ±0.45 rad/mCi, p < 0.001). D2 correlated strongly with D1 for all pts (r = 1.00, p < 0.0001), pts with IRF (r = 1.00, p < 0.0001), & pts with NRF (r = 0.94, p < 0.0001). Similarly, MPAA2 correlated strongly with MPAA1 for all pts (r = 0.95, p < 0.0001), pts with IRF (r = 1.00, p < 0.0001), & pts with NRF (r = 0.94, p < 0.0001). MPAA1 was not normally distributed (Kolmogorov-Smirnov D = 0.12, p = 0.0001), with median = 348 mCi & mean = 413±250 mCi. MPAA2 was lower than MPAA1 (380±215 versus 412±250 mCi, Wilcoxon p < 0.0001), but for activities below the median value of 348 mCi, differences were small (6±12 mCi; 2±4% per cent difference). For activities < 348 mCi, differences between MPAA2 & MPAA1 were similar for pts with IRF and NRF (3±5 versus 8±14 mCi, p = 0.07; 1±2% versus 3±5% per cent difference, p = 0.06). Conclusions: We conclude that maximum permissible administered activity can be accurately determined with as few as 3 blood samples collected over 4 days, regardless of pts9 renal function.
A Labor of Love: The Makings of @FirstGenDocs

This article discusses the origin of @FirstGenDocs, a virtual platform with a mission to affirm the experiences, amplify the voices, and celebrate the brilliance of current and aspiring first-gener...
Single Cell Technologies: Beyond Microfluidics

Abstract Single-cell RNA-sequencing (scRNA-seq) has been widely adopted in recent years due to standardized protocols and automation, reliability, and standardized bioinformatic pipelines. The most widely adopted platform is the 10× Genomics solution. Although powerful, this system is limited by its high cost, moderate throughput, and the inability to customize due to fixed kit components. This study will cover new approaches that do not rely on microfluidics and thus have low entry costs, are highly customizable, and are within the reach of any laboratory possessing molecular biology expertise.
The Stuttering Maestro: The Sick Sinus

In this chapter, the author discusses the historical aspects of the sick sinus syndrome (SSS) and its clinical manifestations, etiology, pathophysiology, clinical evaluation of suspected SSS, and treatment.
Generalized Hierarchy for Exploiting Special Structures in Mixed-Integer Zero-One Problems

In the previous chapter, we discussed a technique for generating a hierarchy of relaxations that span the spectrum from the continuous LP relaxation to the convex hull of feasible solutions for linear mixed-integer 0–1 programming problems. The key construct was to compose a set of multiplication factors based on the bounding constraints 0 ≤ x ≤ e n on the binary variables x , and to use these factors to generate implied nonlinear product constraints, then tighten these constraints using the fact that x j 2 ≡ x j ∀ j = 1, …, n, and subsequently linearize the resulting polynomial problem through a variable substitution process. This process yielded tighter representations of the problem in higher dimensional spaces.
Effect of carrier injection into MESFET substrates - Comparison of MESFET on a semi-insulating buffer, MESFET on a P substrate, and substrate-less MESFET

The carrier injection from the active-layer of the submicron-gate-lengthMesfet into the buffer-layer, or substrate in general, is studied by means of a two-dimensional computer simulation in which the energy conservation equation is simultaneously solved with the carrier conservation equation and Poisson’s equation. The mobility, electron temperature and energy relaxation time are treated as energy dependent parameters. This model is capable of simulating the non-stationary conditions associated with the submicron-gate-length devices. The effect of the carrier injection on the I-V characteristics as well as on the small-signal parameters is investigated by simulating twoMesfet structures; the first is aMesfet on a perfect buffer-layer while the second is a symmetricalMesfet which has no substrate. It is found out that the drain current is increased by the carrier injection, whereas the transconductance is reduced due to the increase of the device dynamic range. TheMesfet with an interfacial potential barrier is also simulated. It exhibits characteristics intermediate between those of the other two devices.
Process variation immunity of alternative 16nm HK/MG-based FPGA logic blocks

Continued miniaturization of semiconductor technology to nanoscale dimensions has elevated reliability challenges of high density Field-Programmable Gate Arrays (FPGA) devices due to increasing impacts of Process Variation (PV). The issue is addressed herein using a systematic bottom-up analysis by determining the relative influence of PV on alternate design realizations of FPGA logic blocks. Results for conventional design structures are obtained through detailed SPICE simulations and related to structural risk features. Namely, Transmission Gate (TG) and Pass Transistor (PT) based MUX architectures for realizing Look-Up-Tables (LUTs) are compared. At threshold voltage variation σ Vth = 14%, PT-based designs that meet the 95% yield objective can exhibit as high delay variation as 23.3%. PV impact can be reduced to 4.9% if TG-based LUT is considered. Finally, the impact of transistor sizing is investigated as a method of mitigating PV susceptibility in FPGA structures.
Urine concentrating mechanism in the inner medulla of the mammalian kidney: role of three-dimensional architecture.

The urine concentrating mechanism in the mammalian renal inner medulla (IM) is not understood, although it is generally considered to involve countercurrent flows in tubules and blood vessels. A possible role for the three-dimensional relationships of these tubules and vessels in the concentrating process is suggested by recent reconstructions from serial sections labelled with antibodies to tubular and vascular proteins and mathematical models based on these studies. The reconstructions revealed that the lower 60% of each descending thin limb (DTL) of Henle’s loops lacks water channels (aquaporin-1) and osmotic water permeability and ascending thin limbs (ATLs) begin with a prebend segment of constant length. In the outer zone of the IM (i) clusters of coalescing collecting ducts (CDs) form organizing motif for loops of Henle and vasa recta; (ii) DTLs and descending vasa recta (DVR) are arrayed outside CD clusters, whereas ATLs and ascending vasa recta (AVR) are uniformly distributed inside and outside clusters; (iii) within CD clusters, interstitial nodal spaces are formed by a CD on one side, AVR on two sides, and an ATL on the fourth side. These spaces may function as mixing chambers for urea from CDs and NaCl from ATLs. In the inner zone of the IM, cluster organization disappears and half of Henle’s loops have broad lateral bends wrapped around terminal CDs. Mathematical models based on these findings and involving solute mixing in the interstitial spaces can produce urine slightly more concentrated than that of a moderately antidiuretic rat but no higher.
Temperature measurements using a lithium niobate (LiNbO 3 ) pyroelectric ceramic

Abstract Temperature measurements from a power generation system could improve its overall safety and efficiency. In addition, real time temperature measurement could lead to a qualitative assessment of the health of the energy system. The challenge of real time temperature measurement inside of a power generation unit lies in the sustainability and the reliability of sensing materials in high temperature and corrosive environments. In this paper, a pyroelectric ceramic material (lithium niobate, LiNbO3) capable of sustaining high temperatures, is considered as the temperature sensing material. LiNbO3 is a pyroelectric material that generates current proportional to the rate of temperature change with time. This property is sustained by LiNbO3 until it reaches its Curie temperature (1210 °C). The generated current could be used for many applications including temperature sensing and energy harvesting from waste heat recovery. This paper presents the temperature measurement results using a LiNbO3 pyroelectric ceramic. Ceramics with dimensions of 1 cm × 1 cm with two different thicknesses, 2 mm and 1 mm, were used as the temperature measurement sensors. Two samples were heated by a 14.5 W/cm2 heat flux and cooled with natural convection. Electrodes were made on both surfaces of the samples with high purity silver paint and two electrical leads were connected to a picoammeter to measure the generated current with respect to the rate of temperature change of the material during heating and natural cooling. A K-type surface thermocouple was attached on top of LiNbO3 to compare the temperature measurements and maximum 8% and 6.7% differences were found for 2 mm and 1 mm thick samples, respectively.
Biosynthesis and characteristics of brain protein and ribonucleic acid in mice subjected to neonatal infection or undernutrition.

A study was made of the biosynthesis of brain protein and ribonucleic acid in mice neonatally infected with an enterovirus or malnourished during early life. These two kinds of stresses caused (a) lasting depression of body weight, (b) decreased biosynthesis of protein and ribonucleic acid in various tissues and subcellular fractions of brain. The depression of body weight in neonatally infected or malnourished mice was partially but not completely corrected by combined administration of growth hormone and insulin. Hormone treatment restored to normal (or beyond) the incorporation of 14C-amino acids into total brain and into subcellular fractions of brain (nuclei, mitochondria, and ribosomes) of infected mice. It also restored the incorporation of 3H-orotic acid into mitochondria of infected and malnourished mice. Remarkable qualitative differences in the patterns of DEAE-cellulose chromatography and polyacrylamide gel electrophoresis were observed among brain-soluble proteins of infected, malnourished, and control groups. These results reveal that early disturbances caused by neonatal infection or undernutrition bring about changes in the metabolism and structure of brain protein.
EFFECT OF BENZYL ALCOHOL ON SUBCELLULAR LACTATE DEHYDROGENASE IN THE MALE RAT

Benzyl alcohol (BA) can evoke cardiac toxicity on the premature newborn when given in conjunction with various injectable medications and/or I.V. flush solutions. Little is known on the underlying mechanism involved. This study evaluates the in vitro effect of BA on rat heart lactate dehydrogenase (LDH) isoenzymes in distinct subcellular fractions as a possible reflection of such toxicity. Both heart H and M subunits were measurable in the nuclear (NC), mitochondrial (MT) and cytoplasmic (CT) fractions of juvenile and adult rats. Presence of 90 mM BA exerted inhibitory action on MT LDH which was age-dependent, i.e., 67% and 59% inhibition of the H subunits occurred in the young and old rats, respectively. The MT M isoenzyme was not inhibited by 90 mMol BA in the young but a 29% inhibition occurred in the old animals. Changes determined in the H subunit of NC-LDH were less profound than those of the MT isoenzyme using the same concentration of BA. The latter concentration exerted only minimal action on the H subunit of the CT fraction of old but not of young rats. The results demonstrate BA toxicity on heart LDH in general and on its H subunit in particular. Also, a differential subcellular LDH sensitivity to BA toxicity was noted. The data suggest that BA adverse cardiac reaction may be associated with altered LDH activity.
3β-Hydroxysteroid dehydrogenase in human placental microsomes and mitochondria: Co-solubilization of androstene and pregnene activities

3 beta-Hydroxysteroid dehydrogenase (3 beta-HSD) was solubilized from human term-placental microsomes and mitochondria using the non-ionic detergent, polyoxyethylene 20 cetyl ether (BrijR-58). Electron photomicrographs showed microsomes and mitochondria well disrupted by the detergent. The pregnene (C-21) and androstene (C-19) activities co-solubilized over a range (0.04-0.44) of BrijR-58/protein (B/P) concentration ratios (w/w). Optimal solubilization of the C-19 and C-21 activities were 63.3 +/- 2.6% (mean +/- SEM) from mitochondria (B/P ratio 0.37) and 71.8 +/- 2.1% from microsomes (B/P ratio 0.34). Detergent treatment of microsomes and mitochondria--varying time (5-90 min, pH 7.4) or varying pH (6.0-7.8, 90 min)--yielded C-19 activities identical with C-21 activities. The C-21/C-19 specific activity ratios of 3 beta-HSD in particulate, solubilized and chromatographed preparations were 2.28 +/- 0.16 (mean +/- SEM) for mitochondria and 1.97 +/- 0.07 for microsomes. 3 beta-HSD molecular weight estimates were 208,000 (microsomes) and 220,000 (mitochondria). These studies argue that a single protein is responsible for both the C-19 and C-21 activities of 3 beta-HSD and that this protein is the same in microsomes and mitochondria.
Cracking the “Black Box”: Journey Mapping's Tracking System in a Drug Court Program Evaluation

ABSTRACT The researchers sought to address client perspectives on the Internet-based Journey Mapping evaluation tool in a drug court program. Ten clients, who used this tool for 3 months, participated in interviews and responded to a short questionnaire. The qualitative data analysis was coded according to the constant comparative method. Clients reported that utilizing Journey Mapping initiated behavioral change, promoted cognitive change, tracked personal treatment progress, and created a way for their program feedback to be considered by staff. Analysis of client data suggested that Journey Mapping enhanced clients' treatment progress, and it not only uncovered program data, but also provided individual clients with their own tangible achievement data.
Vagus nerve stimulation for medically refractory absence epilepsy

Abstract Purpose A proportion of patients with childhood and juvenile absence epilepsies (CAE, JAE) are likely to be classified as medically refractory. In view of evidence gap for the treatment of such patients, this series is reported to generate estimate for efficacy of vagus nerve stimulation (VNS) in this patient population. Methods Patients were identified by a chart review of all VNS recipients between January 1, 2006 and December 31, 2011. The diagnosis of CAE and JAE was based on conventional criteria. Details of demography, epilepsy phenomenology, management and outcomes were extracted. The outcome measures included reduction in daily seizure frequency measured as a percentage of pre-VNS seizure frequency and classified on International League Against Epilepsy (ILAE) outcome scale. Results Nine patients (7 CAE, 2 JAE) with a mean age of seizure onset of 5.4 years (±3.9) were identified. Mean duration of epilepsy prior to VNS implant was found to be 3.9 years (±1.4). These patients had failed a median of 5 anti-epileptic drugs before being referred for consideration of surgical treatment. After a mean follow-up of 33.9 months (±25.5, minimum 4 months), 1 patient attained complete seizure freedom (ILAE class 1), 6 had ILAE class 4 and 2 had ILAE class 5 outcomes, respectively. Mean reduction in daily seizure frequency was found to be 53.5±60.3% (1-sided p -value for paired t -test=0.04), with a 50% responder rate of 55.6%. Conclusion VNS may be considered as a therapeutic option in patients with medically refractory absence epilepsy.
THE GRIEF EXPERIENCE OF OLDER WOMEN WHOSE HUSBANDS HAD HOSPICE CARE

Grief is a universal phenomenon, affecting every age and culture. However, the literature reveals that this concept is surrounded with ambiguity and conflicting research findings. There are few studies which focus on the grief of older widows, and none which focuses on the grief of older women whose husbands received hospice care. The purpose of this longitudinal study was to generate a conceptual definition and theory of grief for older adult women using grounded theory methodology. Informants comprised six older widows whose husbands were enrolled in a hospice programme in a southern metropolitan setting in the United States. Each informant was asked to respond to the initial question: "What is your experience in dealing with the loss of your husband?' Interviews were conducted in the widows' homes after the deaths of their husbands during the following three time frames of bereavement: 1-4 months, 7-10 months and 13-16 months. Interviews were audio-taped, transcribed, coded and analysed using the constant comparative method. Oracle, a text-oriented database management computer program, was used to facilitate the creation, storage, coding, analysis and retrieval of data. Cross-comparisons of the findings from the three phases of data collection were made and these findings were compared with the literature. The following core concepts emerged from the data: "being aware', "experiencing distress', "supporting', "coping' and "facing new realities'. Core concepts were combined into a conceptual definition of grief and a grounded theory of grief of older adult women whose husbands experienced hospice care was developed. The results of this study expand our knowledge of the grief process of older widows whose husbands received hospice care and have implications for the development of effective bereavement intervention programmes.
A Method and Example of Seismically Imaging Near‐Surface Fault Zones in Geologically Complex Areas Using VP, VS, and their Ratios

Abstract The determination of near‐surface (vadose zone and slightly below) fault locations and geometries is important because assessment of ground rupture, strong shaking, geologic slip rates, and rupture histories occurs at shallow depths. However, seismic imaging of fault zones at shallow depths can be difficult due to near‐surface complexities, such as weathering, groundwater saturation, massive (nonlayered) rocks, and vertically layered strata. Combined P ‐ and S ‐wave seismic‐refraction tomography data can overcome many of the near‐surface, fault‐zone seismic‐imaging problems because of differences in the responses of elastic (bulk and shear) moduli of P and S waves to shallow‐depth, fault‐zone properties. We show that high‐resolution refraction tomography images of P ‐ to S ‐wave velocity ratios ( V P / V S ) can reliably identify near‐surface faults. We demonstrate this method using tomography images of the San Andreas fault (SAF) surface‐rupture zone associated with the 18 April 1906 ∼ M 7.9 San Francisco earthquake on the San Francisco peninsula in California. There, the SAF cuts through Franciscan melange, which consists of an incoherent assemblage of greywacke, chert, greenstone, and serpentinite. A near‐vertical zone (∼75° northeast dip) of high P ‐wave velocities (up to 3000 m/s), low S ‐wave velocities (∼150–600 m/s), high V P / V S ratios (4–8.8), and high Poisson’s ratios (0.44–0.49) characterizes the main surface‐rupture zone to a depth of about 20 m and is consistent with nearby trench observations. We suggest that the combined V P / V S imaging approach can reliably identify most near‐surface fault zones in locations where many other seismic methods cannot be applied.
Isolation and characterization of a methionine-rich protein from Maize Endosperm

A 17,000 mol. wt methionine-rich (met-rich) polypeptide from alcohol-soluble reduced glutelin (ASG) of maize endosperm from the hybrid WF9 × Br 38 was purified by a combination of differential solubility and ion exchange chromatography. Antiserum specific for this polypeptide was prepared against a similar fraction purified by Polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (SDS-PAGE) from the inbred W64A. This polypeptide (17,000 mol. wt met-rich ASG) is distinct from zein and other ASG fractions in that it contains the highest levels of methionine (10·8 mol%), glycine, alanine, tyrosine and arginine, and the lowest levels of proline, valine, isoleucine, histidine and phenylalanine among these proteins. Its N-terminal sequence, determined for 36 residues, shows numerous dipeptide (Ala-Gly and Gly-Leu) repeats and it shares no homology with either zein or proline-rich ASG fractions; this lack of homology was also indicated by results from immunological studies.
The Active Site Specificity of the Yersinia Protein-tyrosine Phosphatase

Yersinia protein-tyrosine phosphatase substrates have been synthesized employing an expedient methodology that incorporates phosphorylated non-amino acid residues into an active site-directed peptide. While the peptidic portion of these compounds serves an enzyme targeting role, the nonpeptidic component provides a critical assessment of the range of functionality that can be accommodated within the active site region. We have found that the Yersinia phosphatase hydrolyzes both L- and D-stereoisomers of phosphotyrosine in active site-directed peptides, with the former serving as a 10-fold more efficient substrate than the latter. In addition, this enzyme catalyzes the hydrolysis of a variety of aromatic and aliphatic phosphates. Indeed, a peptide bearing the achiral phosphotyrosine analog, phosphotyramine, is not only the most efficient substrate described in this study, it is also one of the most efficient substrates ever reported for the Yersinia phosphatase. Straight chain peptide-bound aliphatic phosphates of the general structure, (Glu)4-NH-(CH2)2-OPO32- (n = 2-8), are also hydrolyzed, where the most efficient substrate contains seven methylene groups. Finally, a comparison of the substrate efficacy of the peptide-bound species with that of the corresponding non-peptidic analogs, reveals that the peptide component enhances kcat/Km by up to nearly 3 orders of magnitude.
Rheumatologist-patient communication about exercise and physical therapy in the management of rheumatoid arthritis.

Objective Little is known about the features and role of exercise discussions between rheumatologists and patients. The goals of this study were to: 1) describe rheumatologists' and patients' attitudes and beliefs regarding exercise and physical therapy for rheumatoid arthritis (RA); 2) describe frequency and length of exercise discussions; 3) determine the accuracy of recall for exercise discussions; and 4) assess the influence of attitudes regarding exercise on communication about exercise. Methods Goals 1–3 were addressed with analysis of baseline questionnaires and audiotaped encounters. The influence of attitudes and beliefs regarding exercise on the frequency and length of exercise discussions was assessed prospectively. Patients and rheumatologists were enrolled from a large tertiary care institution. Clinical encounters were audiotaped, transcribed, coded, and analyzed to identify specific characteristics of the exercise discussions. Results One hundred thirty-two patients and 25 rheumatologists participated in the study. Rheumatologists and patients discussed exercise in 53% of the encounters. Rheumatologists' beliefs regarding the usefulness of exercise for RA varied, with the least positive beliefs being reported for aerobic exercise. Exercise discussions were more likely to occur if the patient was currently exercising, odds ratio (OR) = 2.4; 95% confidence interval (CI) (1.2–4.9), and when the rheumatologist believed aerobic exercises were useful in managing RA, OR = 1.4; 95% CI (1.1–1.9). Current exercise behavior was associated with patients' positive attitude toward exercise (χ = 8.4; P = 0.004) and perceived social support for exercise (χ = 4.5; P = 0.04). When rheumatologists initiated exercise discussions, there was nearly twice as much discussion (β = −8.4; P = 0.001). Conclusions Exercise talk was influenced by patients' and rheumatologists' beliefs and attitudes regarding the effectiveness of exercise and physical therapy in managing RA, patient experience with exercise, and by characteristics of the rheumatologist.
Viscoelasticity of packed erythrocyte suspensions subjected to low amplitude oscillatory deformation

Concentrated adult erythrocyte suspensions were subjected to low amplitude oscillatory shear in a Weissenberg rheogoniometer equipped with a cone-and-plate assembly. The dynamic viscoelastic properties of the suspension were measured over a broad range of frequency by a numerical solution that accounted for fluid inertia. Variation of shear amplitude and cell volume percent, and comparison of buffered saline, plasma, and dextran as suspending media showed that the cellular elements had undergone small bending and shearing deformations. Studies of normal adult erythrocytes, hypotonically swollen cells, temperature-altered cells, and erythrocyte ghosts suggested that the method was evaluating membrane material properties. The normal membrane was found to exhibit a shear rate dependent elastic modulus that increased by more than a factor of 20 over a frequency range from 0.0076 Hz to 60 Hz. The membrane viscosity showed a substantial drop with frequency indicative of a frequency thinning phenomenon. At high frequency of deformation the viscous response of normal erythrocytes was no longer indicative of a membrane property due to the dominant influence of the internal hemoglobin solution. The studies generally supported the ability of the method to quantify relative membrane material properties and detect changes in membrane structure.
Rejection Sensitivity and Adjustment during Adolescence: Do Friendship Self-Silencing and Parent Support Matter?

This study of 103 adolescents (Mage = 13.73 years) tested whether self-silencing in friendships mediates the associations between rejection sensitivity (RS) and friendship (support) and psychological adjustment (anxiety, depression, loneliness) during early adolescence. Parental support was examined as a moderator of the relation between RS and self-silencing. Results indicated that friendship self-silencing mediated the relations between RS and depression and friendship support. Evidence of moderated mediation was also found: RS and friendship self-silencing were related at high and medium levels of parental support but not at low levels when depression and friendship support served as the dependent variables. Findings suggest that future work on RS and self-silencing in the friendship context is needed and that medium and high levels of parental support may exacerbate certain difficulties associated with RS during early adolescence.
State-Dependent Learning Produced by Depressant and Atropine-Like Drugs*

Rats were trained to escape from shock in a T maze. In this situation a variety of drugs were tested and compared with regard to their ability to produce state-dependent, or dissociated, learning. Three major results were obtained. First, several depressant drugs produced a state in which learning was partially dissociated from learning which occurred in the nondrug state. Pentobarbital, phenobarbital, alcohol, urethane, and meprobamate were approximately equivalent in their actions and were interchangeable. Second, atropine produced a drug state in which learning was partially dissociated from learning in the nondrug state and from learning which occurred under the depressant drugs. The effects of atropine which produced this state neither mimicked nor antagonized those effects of the depressant drugs which allowed them to dissociate learning. This result is especially important as it indicates that not all dissociation phenomena are the result of some single unidimensional process (eg., activation level changes produced by the drugs). Third, many drugs which dissociate learning in other experimental situations have weak or nonexistent dissociative effects on escape learning in the T maze. The present technique appears to be useful for directly comparing the dissociative effects of a variety of drugs.
Effect of reduction conditions on electrocatalytic activity of a ternary PtNiCr/C catalyst for methanol electro-oxidation

Abstract The effect of reduction conditions on a Pt 28 Ni 36 Cr 36 /C catalyst was investigated by using two different reduction methods: hydrogen reduction and NaBH 4 reduction. In hydrogen reduced catalysts, dissolution of metallic Ni and Cr was observed during cyclic voltammetry (CV) tests, and a larger amount of Ni and Cr was dissolved when reduced at higher temperatures. For methanol electro-oxidation, the highest specific current density of 1.70 A m −2 at 600 s of the chronoamperometry tests was observed in the catalyst reduced at 300 °C, which was ∼24 times that of a Pt/C catalyst (0.0685 A m −2 ). In NaBH 4 reduced catalysts, formation of an amorphous phase and a more Pt-rich surface was observed in X-ray diffraction and CV results, respectively, with increasing amounts of NaBH 4 . When reduced by 50 times of the stoichiometric amount of NaBH 4 , the PtNiCr/C catalyst (PtNiCr-50t) showed a current density of 34.1 A g noble metal −1 , which was 81% higher than the 18.8 A g noble metal −1 value of a PtRu/C catalyst at 600 s of the chronoamperometry tests. After 13 h of chronoamperometry testing, the activity of the PtNiCr-50t (15.0 A g noble metal −1 ) was 110% higher than the PtRu/C catalyst (7.15 A g noble metal −1 ). The PtNiCr/C catalyst shows promise as a Ru-free methanol oxidation catalyst.
Male sex pheromone from the wing glands of the indian meal moth, Plodia interpunctella (Hbn.) (Lepidoptera: Phycitidae).

Die Flugeldrusen der Mannchen vonPlodia interpunctella sondern ein Sex-Pheromon aus, das fur den erfolgreichen Vollzug des Balzrituals notwendig ist. Das Pheromon bewirkt, dass das Weibchen nicht flieht und die zur Auslosung der Kopulation notwendige Bereitschaftsstellung einnimmt.
Chemically Homogeneous Complex Oxide Thin Films Via Improved Substrate Metallization

A long-standing challenge to the widespread application of complex oxide thin fi lms is the stable and robust integration of noble metal electrodes, such as platinum, which remains the optimal choice for numerous applications. By considering both work of adhesion and stability against chemical diffusion, it is demonstrated that the use of an improved adhesion layer (namely, ZnO) between the silicon substrate and platinum bottom electrode enables dramatic improvements in the properties of the overlying functional oxide fi lms. Using BaTiO 3 and Pb(Zr,Ti)O 3 fi lms as test cases, it is shown that the use of ZnO as the adhesion layer leads directly to increased process temperature capabilities and dramatic improvements in chemical homogeneity of the fi lms. These result in signifi cant property enhancements (e.g., 300% improvement to bulk-like permittivity for the BaTiO 3 fi lms) of oxide fi lms prepared on Pt/ZnO as compared to the conventional Pt/Ti and Pt/TiO x stacks. A comparison of electrical, structural, and chemical properties that demonstrate the impact of adhesion layer chemistry on the chemical homogeneity of the overlying complex oxide is presented. Collectively, this analysis shows that in addition to the simple need for adhesion, metal-oxide layers between noble metals and silicon can have tremendous chemical impact on the terminal complex oxide layers.
A closure associative processor

The authors describe a bidirectional associative processor that stores a hierarchy of entities and characteristics as an adjacency matrix. The matrix is unipolar binary, which allows it to be easily stored in a spatial light modulator and makes it attractive for optical implementation. A large hierarchy can be separated into subhierarchies and stored in separate processors. The authors discuss how the processor can perform upward and downward closure, union, intersection, and complementation with the aid of simple electronics (a register, thresholders, exclusive-OR and inverter gates). By combining series of these operations, the processor can answer nontrivial queries. >
Matrix mineralogy of the Lance CO3 carbonaceous chondrite - A transmission electron microscope study

Results are presented on electron microprobe analyses of three CO chondrites, all of which are falls: Lance, Kainsaz, and Warrenton. The TEM mineralogy results of Lance chondrite show that Fe-rich matrix olivines have been altered to Fe-bearing serpentine and Fe(3+) oxide; matrix metal was also altered to produce Fe(3+) oxides, leaving the residual metal enriched in Ni. Olivine grains in Lance's matrix contain channels along their 100-line and 001-line directions; the formation and convergence of such channels resulted in a grain-size reduction of the olivine. A study of Kainsaz and Warrenton showed that these meteorites do not contain phyllosilicates in their matrices, although both contain Fe(3+) oxide between olivine grains. It is suggested that, prior to its alteration, Lance probably resembled Kainsaz, an unaltered CO3 chondrite.
SSME leak detection feasibility investigation by utilization of infrared sensor technology

This investigation examined the potential of using state-of-the-art technology of infrared (IR) thermal imaging systems combined with computer, digital image processing and expert systems for Space Shuttle Main Engines (SSME) propellant path peak detection as an early warning system of imminent engine failure. A low-cost, laboratory experiment was devised and an experimental approach was established. The system was installed, checked out, and data were successfully acquired demonstrating the proof-of-concept. The conclusion from this investigation is that both numerical and experimental results indicate that the leak detection by using infrared sensor technology proved to be feasible for a rocket engine health monitoring system.
Critical comments on applying covariance structure modeling

Covariance structure modeling, also known as structural equation modeling or causal modeling, appears increasingly popular. Such techniques can be used to conduct tests of complex theory on empirical data. To conduct such tests, researchers need measures of known factor structure and the knowledge of structural relations among the constructs of interest. Researchers typically have neither the required measures nor the knowledge of structural relations. Instead of conducting tests of theory, researchers use covariance structure models to develop measurements and theoretical models. This paper discusses why such use of covariance structure models is unlikely to produce scientific progress and proposes some alternative procedures thought to be more fruitful.
Postirradiation Ductility Demonstration Tests of Weapons-Derived MOX Fuel Cladding

The U.S. Department of Energy (DOE) Fissile Materials Disposition Program (FMDP) is pursuing reactor irradiation of mixed uranium-plutonium oxide (MOX) fuel for disposal of surplus weapons-usable plutonium. Since most of the MOX fuel utilization experience has been with reactor-grade plutonium, it is desired to demonstrate that the unique properties of the surplus weapons-derived or weapons-grade (WG) plutonium do not compromise the applicability of this MOX experience base. A related question to be addressed for weapons-derived MOX fuel is that of ductility loss of the cladding. While irradiation induced loss of ductility has long been known and quantified for many cladding materials, the potential synergistic effects of irradiation and the unique constituents (i.e., gallium) of weapons-derived MOX fuel are not known. As part of an extensive fuel qualification research program conducted by Oak Ridge National Laboratory (ORNL), a new test method was developed and validated to measure the room temperature ductility and hoop tensile properties of MOX fuel cladding. The cladding material is a zirconium alloy designated as Zr-4 manufactured by Sandvick Corporation. This paper is a summary of the test method developed and of demonstration test results obtained for MOX cladding irradiated to 21 GWd/MT [7 × 1020 n/cm2 (E > 1 MeV)].Copyright © 2004 by ASME
The master therapist : Ideal character or clinical fiction? comments and questions on jennings and skovholt's the cognitive, emotional, and relational characteristics of master therapists

L. Jennings and T. M. Skovholt's (1999) study constitutes a useful step toward deepening scientific understanding of what therapists at their best are capable of offering to their clients. Both the study's strengths and limitations stimulate questions, which this commentary attempts to consider. These questions mainly concern the lack of a clear initial definition of master therapist, the lack of meaningful comparison groups needed to infer the distinctive characteristics of master therapists, the incomplete communication of data-analytic procedures, and the formulation of results as a uniform ideal-typical pattern that precludes recognition of individual differences. Despite this, the clinical richness of the findings is well appreciated, and the questions stimulated by the study indicate its high heuristic value.
Results of different surgical procedures on total knee arthroplasty infections

Abstract Seventy-six consecutive infected total knee arthroplasties in 74 patients were treated between December 1981 and March 1990. The average follow-up period was 57 months (range, 24–121 months). No patients were lost to follow-up evaluation and 12 patients died from unrelated causes. Patients were classified, based on the duration of their symptoms prior to treatment, as acutely infected ( 2 weeks). All knees were evaluated following surgical treatment with radiographs and Knee Society knee score assessment. Successful eradication of infection was defined as a knee without clinical evidence of infection for a minimum of 2 years. The initial treatment modality was successful in eliminating the infection in 69 of 76 patients (90%). Infection was eventually eradicated in 72 of 76 (94%) patients. The individual clinical result was found to be more dependent on a patient's medical and musculoskeletal status (patient class A, B, C) than on knee score or radiographic assessment. Careful treatment selection based on patient class and duration of infection can result in a predictable and successful result.
Strain measurements in cultured vascular smooth muscle cells subjected to mechanical deformation.

Early work in the field of biomechanics employed rigorous application of the principles of mechanics to the study of the macroscopic structural response of tissues to applied loads. Interest in the functional response of tissues to mechanical stimulation has lead researchers to study the biochemical responses of cells to mechanical loading. Characterization of the experimental system (i.e., specimen geometry and boundary conditions) is no less important on the microscopic scale of the cell than it is for macroscopic tissue testing. We outline a method for appropriate characterization of cell deformation in a cell culture model; describe a system for applying a uniform, isotropic strain field to cells in culture; and demonstrate a dependence of cell deformation on morphology and distribution of adhesion sites. Cultured vascular smooth-muscle cells were mechanically deformed by applying an isotropic strain to the compliant substrate to which they were adhered. The state of strain in the cells was determined by measurement of the displacements of fluorescent microspheres attached to the cell surface. The magnitude and orientation of principal strains were found to vary spatially and temporally and to depend on cell morphology. These results show that cell strain can be highly variable and emphasize the need to characterize both the loading conditions and the actual cellular deformation in this type of experimental model.