cssi/SciSciGPT-SciSciNet huggingface dataset:
TH-A-9A-08: Knowledge-Based Quality Control of Clinical Stereotactic Radiosurgery Treatment Plans

Purpose: To develop a quality control tool to reduce stereotactic radiosurgery (SRS) planning variability using models that predict achievable plan quality metrics (QMs) based on individual patient anatomy. Methods: Using a knowledge-based methodology that quantitatively correlates anatomical geometric features to resultant organ-at-risk (OAR) dosimetry, we developed models for predicting achievable OAR dose-volume histograms (DVHs) by training with a cohort of previously treated SRS patients. The DVH-based QMs used in this work are the gradient measure, GM=(3/4pi)^1/3*[V50%^1/3−V100%^1/3], and V10Gy of normal brain. As GM quantifies the total rate of dose fall-off around the planning target volume (PTV), all voxels inside the patient's body contour were treated as OAR for DVH prediction. 35 previously treated SRS plans from our institution were collected; all were planned with non-coplanar volumetric-modulated arc therapy to prescription doses of 12–25 Gy. Of the 35-patient cohort, 15 were used for model training and 20 for model validation. Accuracies of the predictions were quantified by the mean and the standard deviation of the difference between clinical and predicted QMs, δQM=QM_clin−QM_pred. Results: Best agreement between predicted and clinical QMs was obtained when models were built separately for V_PTV 2.5cc. Eight patients trained the V_PTV 2.5cc models, respectively. The mean and the standard deviation of δGM were 0.3±0.4mm for the training sets and −0.1±0.6mm for the validation sets, demonstrating highly accurate GM predictions. V10Gy predictions were also highly accurate, with δV10Gy=0.8±0.7cc for the training sets and δV10Gy=0.7±1.4cc for the validation sets. Conclusion: The accuracy of the models in predicting two key SRS quality metrics highlights the potential of this technique for quality control for SRS treatments. Future investigations will seek to determine whether QM variations are due to residual model inaccuracies or true plan quality variations in the clinical sample. Support from Varian Medical Systems.
Vinylsilylene rearrangement. A possible silacyclopropanylidene intermediate

Abstract It is proposed that trimethylsilylvinylsilylene undergoes sequential rearrangement to a silacyclopropanylidene by silene to silylene isomerization of an intermediate 1-silacyclopropene.
On offense history and the theory of deterrence

Abstract This article uses a two-period version of the standard economic model of deterrence to study whether sanctions should depend on an individual’s record of prior convictions—his offense history. The principal contribution of the article is to demonstrate that it may be optimal to treat repeat offenders disadvantageously because such a policy serves to enhance deterrence: When an individual contemplates committing an offense in the first period, he will realize that if he is caught, not only will he bear an immediate sanction, but also—because he will have a record—any sanction that he bears in the second period will be higher than it would be otherwise.
Failure diagnosis and decision making in industrial processes: A fuzzy set application

The main purpose of failure diagnosis is to analyze any pattern of defects or process malfunctions and to indicate which factors are the most likely causes of those defects. This paper provides a review of the different techniques used to perform this diagnostic analysis. After a brief description of traditional methods, the two most recent approaches, based on production rules and fuzzy set theory, are presented. The two major trends of the fuzzy set based approach are then described. The first one is a fuzzy extension of classical cluster analysis techniques. The second one is the solution of the inverse problem for compositions of fuzzy relations. A different technique, based on the fuzzy relation and the use of fuzzy numbers, is then discussed.
Dodecylamine and other agents active against Ascaris lumbricoides and their toxicity in mammals.

1. Allyl isothiocyanate, dodecylamine, and γ-choroallyl dodecylamine exhibited the same degree of anthelmintic activity as hexylresorcinol on the Ascaris lumbricoides of swine in vitro. 2. Single peroral doses (from 1.02 to 1.6 Gm./Kg.) of hexylresorcinol, dodecylamine, and γ-chloroallyl dodecylamine have approximately the same toxic range in mice and rats. Allyl isothiocyanate is moderately toxic in the range of 0.112 Gm./Kg. 3. γ-chloroallyl dodecylamine is less irritating to the membranes of the rabbit's eye than hexylresorcinol, allyl isothiocyanate, or dodecylamine, and has no permanent effect visible at 96 hours. 4. Hexylresorcinol, dodecylamine, and γ-chloroallyl dodecylamine exhibit the same degree of surface activity, which might be given as an explanation for their mechanism of action. 5. Further study is necessary to determine the relationship of structure to action of aliphatic compounds like dodecylamine and γ-chloroallyl dodecylamine, which may have anthelmintic value in both human and animal disease. 6. The active dodecylamines represent a type of agent not previously known to posses anthelmintic properties. Dodecylamine should be handled with care, since one of six people engaged in working with it in our laboratory developed a dermatitis, characterized by ‘blood blisters’ on two fingers.
COMPOSITIONAL EFFECTS ON THE RADIATION DAMAGE OF 2 MEV SI ION IMPLANTED RELAXED SI1-XGEX ALLOYS

Abstract The radiation damage of relaxed Si1−xGex alloys with 0.04≤x≤0.36 after 2 MeV Si ion implantation at 300 K has been studied as a function of dose. Optical reflectivity depth profiling (ORDP) is used to determine quantitatively depth profiles of the lattice damage. While for sufficiently low doses the shape of damage profiles is similar to that of the nuclear stopping power, composition dependent changes in profile shape are observed at doses where defects produced in different collision cascades may interact. Damage at any depth is observed to increase with increasing Ge content of the alloy. The dose dependence of damage is described by a damage accumulation model for the depth of damage maximum. From the model parameters it is concluded that the stronger damage in the more Ge-rich alloys is mainly due to a stronger production of amorphous volume portions in individual collision cascades.
Matrix Extracellular Phosphoglycoprotein (MEPE) Is a New Bone Renal Hormone and Vascularization Modulator

Increased matrix extracellular phosphoglycoprotein (MEPE) expression occurs in several phosphate and bone-mineral metabolic disorders. To resolve whether MEPE plays a role, we created a murine model overexpressing MEPE protein (MEPE tgn) in bone. MEPE tgn mice displayed a growth and mineralization defect with altered bone-renal vascularization that persisted to adulthood. The growth mineralization defect was due to a decrease in bone remodeling, and MEPE tgn mice were resistant to diet-induced renal calcification. MEPE protein-derived urinary ASARM peptides and reduced urinary Ca X PO4 product mediated the suppressed renal calcification. Osteoblastic cells displayed reduced activity but normal differentiation. Osteoclastic precursors were unable to differentiate in the presence of osteoblasts. In the kidney, NPT2a up-regulation induced an increase in phosphate renal reabsorption, leading to hyperphosphatemia. We conclude MEPE and MEPE-phosphate-regulating gene with homologies to endopeptidases on the X chromosome (MEPE-PHEX) interactions are components to an age-diet-dependent pathway that regulates bone turnover and mineralization and suppresses renal calcification. This novel pathway also modulates bone-renal vascularization and bone turnover.
Bicuspid noncalcific aortic stenosis: Diagnostic limitations of intraoperative transesophageal echocardiography

calcific aortic stenosis requiring aortic valve replacement) The valves may be unicommissural, acommissural unicuspid, or, most commonly, bicuspid with two distinct leaflets and commissures. 4 Estimation of the severity of stenosis is most often determined by (1) direct short-axis measurement of the aortic valve area and (2) Doppler estimates of transvalvular gradients and valve area. 4 Measurement of the maximum, long-axis aortic cusp separation and qualitative assessment of leaflets motion may also be used to estimate severity of stenosis. This case highlights the pitfalls of both the direct short-axis and the Doppler methods of assessing severity of aortic stenosis by TEE, and the beneficial effects of a comprehensive, routine TEE examination on the diagnostic process. Reported success rates for short-axis planimetry of the true orifice of the aortic valve range from 13% to 85%. 5-8 One suggested reason for a low success rate is the imaging constraint imposed by supero-inferior motion of the aortic valve in and out of the imaging plane during the cardiac cycle. Further, systolic doming of the leaflets would be expected to compound the technical difficulties involved in obtaining valid short-axis measurements by furnishing the potential for the beam of interrogation to transect the leaflets before the actual stenotic valve orifice. Such a situation would provide an image of an apparently normal orifice (Fig 2). However, the true degree of stenosis was readily evident with long-axis imaging (Fig 3), Systolic doming of the leaflets, with overshoot of leaflet tissue
Evaluation Of Optical System Image Quality From Measured Aspheric Replica Master Data Using The Accos V Spline Program

In the manufacture of small primary and secondary replicated mirrors used in tactical missiles one of the most critical decisions is when to accept a master to be used for the replication process. A method has been developed whereby actual measured data on each master can be input to the ACCOS V optical design program so as to appropriately distort the ideal mirror design contour in such a manner as would result from the use of these masters. The resultant image can then be evaluated in terms of blur circle diameter, MTF or whatever other convenient image evaluation criteria one may wish to use. To accomplish this task a program was written to accept the measured data from the masters and translate it into a form compatible with the SPLINE subroutine input format for each mirror. Once this was accomplished normal ACCOS V evaluations were performed. An example is given to demonstrate the steps needed to achieve the above evaluation, including SPLINE curve fitting, interpolation, input sequencing, storage manipulations and image quality evaluation.© (1977) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
A Buried Polar Residue in the Hydrophobic Interface of the Coiled-coil Peptide, GCN4-p1, Plays a Thermodynamic, not a Kinetic Role in Folding

The hydrophobic interfaces of coiled-coil proteins and peptides are typically interspersed with buried polar residues. These polar residues are known to be important for defining oligomeric specificity and chain orientation in coiled-coil formation; however, their effects on the folding/assembly reaction have not been investigated. The commonly studied 33-residue dimeric leucine zipper peptide, GCN4-p1, contains a single polar Asn in the center of the hydrophobic interface at position 16. Peptides containing either a valine or an alanine replacement at this position, N16V and N16A, respectively, were studied in order to investigate both the thermodynamic and kinetic roles of the buried polar side-chain on the folding of GCN4-p1. Equilibrium sedimentation confirmed that both the N16V and N16A mutations reduce the dimeric specificity of GCN4-p1, leading to the population of both dimers and trimers in the absence of denaturant. Guanidine hydrochloride-induced equilibrium unfolding of the mutant peptides demonstrated that N16V is more stable than the wild-type sequence, while the N16A peptide is moderately destabilized. Comparison of the refolding reactions indicate that Asn16 is not involved in the rate-limiting association step leading to the native dimer; only the unfolding reaction is sensitive to the mutations. More complex unfolding kinetics for both peptides at high peptide concentrations can be attributed to the presence of trimers in the absence of denaturant. These results show that the role of buried polar residues in leucine zipper peptides can be primarily thermodynamic; subunit exchange reactions can be controlled by the stability of the native coiled coil and its influence on the unfolding/dissociation process.
Observations of Facet Formation in Near-α Titanium and Comments on the Role of Hydrogen

Faceted features are frequently observed on the fracture surfaces of titanium alloys that have failed by static loading, continuous cycling, dwell fatigue loading, and stress corrosion cracking (SCC). Although the facets formed under different loading conditions seem qualitatively similar, there are significant differences in the spatial and crystallographic orientations of the facets as well as subtle differences in facet surface topography. The current study compares and contrasts facets for various loading conditions (cyclic, creep, SCC, and dwell) in the Ti-8Al-1Mo-1V alloy with the primary motivation being to understand the mechanisms of crack initiation and faceted growth during dwell fatigue. The spatial and crystallographic orientations of the facets were determined using quantitative tilt fractography and electron backscatter diffraction, whereas facet topography was examined using ultra-high-resolution scanning electron microscopy. Collectively, the experimental observations suggest that hydrogen may play an important role in facet formation and accelerating small crack growth rates during dwell fatigue loading.
The high-albedo kuiper belt object (55565) 2002 AW197

We detected thermal emission from the Kuiper Belt object 2002 AW197 in 2003 December and again in 2004 April using the Multiband Imaging Photometer on the Spitzer Space Telescope. In combination with the absolute visual magnitude, the thermal measurements indicate a geometric albedo of 0.17 ± 0.03 and a diameter of 700 ± 50 km. The albedo of 2002 AW197 is significantly higher than the 0.04 value typically assumed for trans-Neptunian objects, and consequently the object is smaller than previously thought based on that assumption. Our thermal measurements at two wavelengths (24 and 70 μm) allow us to constrain the surface temperature and thereby place constraints on the thermal inertia. We find that the standard thermal model (STM) is inconsistent with the 24/70 μm color unless we set the beaming parameter η > 0.95, indicating that the object has a significant thermal inertia and, therefore, that the STM is inappropriate. The other end-member thermal inertia model is the fast-rotator, or isothermal-latitude, model (ILM). The data are well represented by an ILM with the pole of rotation inclined to the Sun by 45° ± 10°. The high albedo is consistent with a surface containing significant amounts of weakly absorbing materials, with ices and/or fine-grained silicates as likely candidates.
The effects of climate, host plant phenology and host fidelity on the genetics of apple and hawthorn infesting races of Rhagoletis pomonella

True fruit flies belonging to the Rhagoletis pomonella (Walsh) sibling species complex have been proposed to speciate sympatrically by shifting and adapting to new host plants. Here, we report the results from a series of ecological and genetic experiments conducted at a study site near Grant, Michigan, U.S.A., aimed at clarifying the relationship between host specialization and reproductive isolation for these flies. Our findings indicate that apple (Malus pumila) and hawthorn (Crataegus mollis) infesting populations of R. pomonella are partially allochronically isolated. Differences in the timing of adult eclosion account for part of the allochronic divergence, as apple adults emerge approximately ten days earlier than hawthorn flies in the field. Genetic analyses across different life history stages of the fly show that adults do not randomly move between apple and hawthorn trees, but trend to attack the same species of plant that they infested as larvae. Estimates of interhost migration from the allozyme data suggest that from 2.8 to 10% of the apple population is of hawthorn origin and that over 20% of the hawthorn population is of apple origin. The length and quality of the growing season appear to affect the genetic composition of the host races, as allele frequencies in the hawthorn population are correlated with ambient temperature and rainfall during the spring of the preceding year. Finally, allele frequencies for six allozyme loci displaying host associated differentiation also show significant linear regressions with the timing of adult eclosion within both races. These regressions establish a link between allozyme loci displaying inter-host differentiation and a developmental trait (adult eclosion) responsible for partially isolating the races. The slopes of the regressions are paradoxical, however, as they suggest that apple adults should eclose later, not earlier, than hawthorn flies. We conclude by discussing potential resolutions to the eclosion time paradox.
Anatomic features of reduced-size liver transplant: postsurgical imaging characteristics.

In this retrospective review, the authors evaluated the anatomic and imaging features of 140 reduced-size liver transplants in 120 boys and girls; 100 of these patients (83.3%) were 2 years old or younger. The authors reviewed the surgical reports, plain radiographs, contrast material-enhanced studies of the gastrointestinal tract, duplex Doppler and color Doppler ultrasound (US) scans, and computed tomographic (CT) scans. Understanding the anatomic features associated with transplantation was crucial to understanding the post-surgical imaging characteristics. Changes in visceral anatomic structure caused a variety of imaging appearances, some of them misleading: (a) Some patients had unusual bowel gas patterns on plain radiographs because of a shift in location by bowel loops; (b) gastrointestinal studies showed gastric compression by an oversized left lobe that mimicked mass effect; and (c) displacement or migration of the duodenum, jejunum, or cecum into the right hepatic fossa sometimes mimicked malro...
The effect of FDG-PET on the stage distribution of non-small cell lung cancer.

Purpose To study the impact of 18 F-fluorodeoxyglucose positron emission tomography (FDG-PET) on stage distribution and survival for patients with newly diagnosed non-small cell lung cancer (NSCLC). Methods We searched the Barnes-Jewish Hospital/Washington University School of Medicine database for patients with non-small cell lung cancer (NSCLC) diagnosed between January 1, 1990 and December 31, 2004. Since the use of FDG-PET increased in our institution in the year 2000, patients were subdivided into those diagnosed before or after January 1, 2000. We compared the stage distribution of NSCLC before and after the year 2000. We also compared the survival for patients diagnosed between 2000 and 2004 staged with or without FDG-PET. Results We identified 6118 patients diagnosed with NSCLC, with 3765 (61%) diagnosed before the year 2000 and 2362 (39%) thereafter. The use of FDG-PET was significantly increased after the year 2000 (37% versus 7%, p p Conclusion The increased use of FDG-PET was associated with a stage migration in patients with NSCLC, which may partially account for improvements in survival as compared with historical controls.
The influence of first pass metabolism on the development and validation of an IVIVC for metoprolol extended release tablets

Abstract To investigate the influence of α-hydroxymetoprolol (AHM) and 4-(2-hydroxy-3-isopropylaminopropoxy)-phenylacetic acid (ACMB), both derived from its first pass metabolism of metoprolol, an in vitro in vivo correlation incorporating first pass metabolite data for metoprolol extended release formulations was developed. Three different releasing formulations (slow (S), moderate (M) and fast (F), 100 mg) of metoprolol were evaluated in a previously reported clinical study. The non-first pass effect (Non-FPE) in vitro in vivo correlation (IVIVC) was developed using a fraction of metoprolol dissolved and a fraction of total drug (metoprolol+metabolites) as the absorption data for various combinations of formulations (S/M/F, M/F, S/M, and S/F). Direct convolution approaches predicting metoprolol concentrations and indirect convolution predicting total drug concentrations (metoprolol+metabolites) were used to determine in vivo behavior. The Non-FPE IVIVC using the S/M/F formulations displayed the strongest relationship ( r 2 >0.92). The IVIVC using the indirect approach was predictive of both the C max (prediction errors (PE) 4.77, 3.94 and 6.14%) and AUC (10.7, 11.0 and 11.3%) for metoprolol, AHM and ACMB. Poor predictability (PE>40% for C max and AUC) was observed for metoprolol when using the direct methods. The predictability of the IVIVC using the indirect approach as compared to the direct method displays the influence of first pass metabolism on the development and evaluation of an IVIVC for a drug that displays a high extraction ratio. In addition, the indirect IVIVC allows for not only predicting the in vivo performance of the parent drug but also the metabolites formed via the first pass effect.
Conversion of the cholesterol sidechain to a 17-acetyl group by remote chlorination reactions

Two methods to convert cholesterol to pregnane derivatives are described. In one, template directed chlorination of C-20 with an iodoaryl ester attached at the 6 β position was used to convert i-cholesterol to pregnenolone.
The 2014 Frank Stinchfield Award: The ‘Landing Zone’ for Wear and Stability in Total Hip Arthroplasty Is Smaller Than We Thought: A Computational Analysis

Background Positioning of total hip bearings involves tradeoffs, because cup orientations most favorable in terms of stability are not necessarily ideal in terms of reduction of contact stress and wear potential. Previous studies and models have not addressed these potentially competing considerations for optimal total hip arthroplasty (THA) function.
Characterization of an integrated-optical pipelined polynomial processor

A polynomial evaluator utilizing a pipelined architecture has been constructed and tested. Some notable features of this processor are its unusual design its speed in polynomial evaluation and its ability to rapidly compute the zeros of polynomials. This optical computer utilizes sequential processing by seven electrooptic gratings which perform alternate addition and multiplication functions in the pipeline. Its performance as a square-root processor and as a cubic polynomial evaluator are stressed. Characterization measurements upon the individual gratings and upon the processor as a system are presented. 1.
Toys to fall for or live with

Children's Attachments to Artifacts tackles some of the paradoxes generated by "instant" consumer satisfaction approaches, including cognitive studies, and advocates a developmental approach to studying how a child's relation with artifacts evolves over time (I grow with my toys, and my toys grow with me).
Reinforcement of elastomeric poly(dimethylsiloxane) by glassy poly(diphenylsiloxane)

Some novel approaches were taken to provide the improvements in mechanical properties that are almost always necessary to prepare a commercially useful elastomer from poly(dimethylsiloxane) (PDMS) [-Si(CH3)2O-]. The reinforcement was provided by poly(diphenylsiloxane) (PDPS) [-Si(C6H5)2O-], a hard glassy polymer, which was introduced into the PDMS by two rather different techniques. In the first, the PDPS was prepared separately by condensation polymerization of diphenylsilanediol and then solution-blended into the PDMS. In the second, it was generated by in situ polymerization of the same monomer absorbed into the PDMS network. The resulting materials were characterized by scanning electron microscopy and by stress-strain isotherms in elongation. At least under some conditions both techniques were found to be successful, leading to increases in ultimate strength by a factor of two or more.
A Simplified Basic Classification of Spatial Alignments of the Heart, Its Chambers, and the Great Vessels

The problems resulting from a lack of accepted terminology and a basic classification system for the various spatial alignments of the heart, its chambers and great vessels are reviewed. A basic simplified classification system founded on fundamental embryologic, clinical, and roentgenologic considerations is proposed. Terminology employed is precisely defined. The clinical studies needed to place patients in their category are enumerated and discussed. It is recognized that some forms of spatial derangement defy classification within this system. Nevertheless, this classification system with the suggested terminology, however inadequate, is offered as a means to promote clinical definition of these entities and to encourage clear discussion and a better understanding of these conditions. It is hoped that future study will add to our knowledge of the embryologic mechanisms involved and eventually lead to a more comprehensive classification embracing a larger number of congenital cardiac anomalies.
Strategies of Conflict: Custody Litigation in the United States.

Contested child custody cases between divorcing parents provide a context for examining the interconnections between legal and familial processes. The paper examines the structure of the legal system in relation to the factors leading to custody litigation, the strategies of parents contesting the custody of their children, and the impact of these actions on the legal system and the family. The research is based on ethnograpghic fieldwork in a circuit and domestic relations court.
Continuous Corticosteroids for Refractory Poorly Differentiated Lymphocytic Lymphoma

ABSTRACT: Two patients with stage IV poorly differentiated lymphocytic lymphoma became refractory to intensive combination chemotherapy that contained intermittent corticosteroids. Both patients had evidence of bone marrow replacement and leukemia. Continuous corticosteroids were substituted and produced remissions for more than 1 year for both patients. This alteration in schedule offers an inexpensive and effective palliative treatment for this incurable disease.
Metabolism of intratracheally administered unsaturated phosphatidylcholines in adult rabbits.

Twenty-five adult rabbits were each injected intratracheally with a solution containing 1-palmitoyl-2-[3H]palmitoyl phosphatidylcholine (DPPC) and 1-palmitoyl-2-[14C]oleoyl-PC that had been associated with32P-labeled natural rabbit surfactant. The animals were killed in groups of 5 at 1, 4, 8, 15 and 24 h after isotope injection. Isotope recovery and PC specific activities were measured in alveolar washes, lung homogenates, lamellar bodies and microsomes. The percent clearance per h of PC was very similar for the three labels and were; 3.56, 3.44 and 3.00%, respectively, for the3H-,14C- and32P-labeled PC in the total lung (alveolar wash plus lung homogenate) and 3.84, 3.79 and 3.70%, respectively, for alveolar wash alone. The intracellular pathways of the three labels were assessed by comparing the specific activities in the lamellar bodies over 24 h as well as comparing the ratios of lamellar body to microsome specific activities over this period. These ratios were very similar for the monoenoic and saturated PC labels over time, indicating comparable recycling. In a separate experiment, three other unsaturated species; 1,2-[14C]dioleoyl-PC, 1-palmitoyl-2-[14C]linoleoyl-PC, and 1-palmitoyl-2-[14C]arachidonyl-PC were compared to 1-palmitoyl-2-[14C]oleoyl-PC. Recovery in the alveolar wash and total lung were similar at 16 h for all four labeled phospholipids. The intracellular pathways were also similar, except for the arachidonyl compound. More radiolabel was found in the microsomal fraction relative to the lamellar bodies as compared to the other. Thus, the catabolic pathways were similar for the saturated and unsaturated PC species initially present in the airspaces. The only metabolic difference between the compounds appears to be in the intracellular handling of the arachidonic species.
The Relationship between Parenting Styles, Sons' Self-Restraint, and Peer Relations in Early Adolescence:

Self-restraint was studied as a social competency that may partly explain the link between parenting techniques and early adolescent boys' relationships with peers. Information on parenting styles and family social support was obtained from 92 mothers, 67 fathers, and 92 sixth-grade boys. Classroom teachers rated boys' self-restraint and classmates nominated boys they liked most and liked least. Correlations and regression analyses linked sons' self-restraint to both parenting and peer relations. Parenting and social support from families also contributed unique variance to sons `peer relations, over and above their contribution to sons' self-restraint. Specifically, parental child-centeredness was a significant, positive predictor of being liked by peers, whereas parental harsh discipline was a significant, positive predictor of social impact on peers. In contrast to other work in this area, these findings were obtained using separate informants to assess mothers' and fathers' child-rearing styles, boys'...
In vitro and in vivo effects of sodium selenite on 7,12-dimethylbenz[a]anthracene--DNA adduct formation in isolated rat mammary epithelial cells.

Supplementation with increasing quantities of selenium (Se), as sodium selenite, to cultures of rat mammary epithelial cells resulted in a proportional depression in 7,12-dimethylbenz[a]anthracene (DMBA) binding to DNA. A depression in the two major anti bay-region dihydrodiol epoxide-deoxyribonucleoside adducts largely accounted for the reduced binding. DMBA-DNA binding in freshly isolated mammary cells from rats fed a diet containing 2.0 p.p.m. Se and incubated in culture with DMBA for 24 h was decreased 32% compared to binding in cells obtained from rats fed 0.1 p.p.m. Se. DMBA-DNA binding in mammary cells obtained from rats fed supplemental Se for 2 weeks or more was depressed compared to that occurring in cells from unsupplemented rats. The reduced ability of cells obtained from rats previously fed a 2.0 p.p.m. Se diet to activate DMBA to intermediates capable of binding to DNA became increasingly apparent with the duration of exposure to the carcinogen. Consistent with the in vitro supplementation study, cells isolated from rats previously fed a diet containing 2.0 p.p.m. Se had a reduced occurrence of the two major anti dihydrodiol epoxide adducts. The depression in DMBA binding following selenite supplementation, both in vitro and in vivo, supports the ability of Se to inhibit the initiation phase of carcinogenesis.
Effect of steam versus dry-heat sterilization on the wear of orthodontic ligature-cutting pliers * ** * ** * ♢♢

The purpose of this study was to compare the wear of orthodontic ligature-cutting pliers after multiple cycles of cutting stainless steel ligature wire (.025 mm) and sterilizing with dry heat or steam autoclave. Fifty ligature-cutting pliers with stainless steel inserts were randomly divided into 2 equal groups to be sterilized in either dry heat or steam autoclave. Each plier was subjected to a series of ligature wire cuts followed by the assigned sterilization method. The amount of wear at the tip of each plier in both groups was measured with a stereo microscope system and digital photomicrography. Wear was defined as the difference in initial length from a marked reference line to the tip of the plier minus the length after 6 and 12 cycles of use and sterilization. There was no significant difference in the mean wear at the tip of the pliers between the 2 groups. It appears that there is no need to maintain both sterilization systems, dry heat and steam autoclave, in the orthodontic office. Steam autoclave sterilization can be used with no deleterious effects on the pliers if they are manufactured with stainless steel inserts.
Has the Russian Federation Been Chechenised

In every victory, there is a defeat; in every defeat, a victory. (Russian Proverb) Did Chechnya Chechenise Vladimir Putin before Putin Chechenised Chechnya? To what extent was Vladimir Putin's appr...
The role of bile reflux in the development of cold-restraint gastric lesions.

The study was designed to test whether or not bile reflux is necessary for the development of gastric mucosal lesions during cold-restraint stress in the rat. 40 male Sprague-Dawley rats were studied. They were randomized into 4 groups. Group 1 underwent sham operations with no cold-restraint stress. Group 2 underwent sham operations. Group 3 underwent pyloric ligation. Group 4 underwent bile duct ligation. Groups 2, 3, and 4 were subjected to cold-restraint stress for 3 hours at 4–6° C in a Bollman cage. After the experimental procedure, the stomachs were removed under ether anesthesia, the severity of lesions was recorded, and blood from the hearts was obtained for hematocrit readings. The mean lesion scores of all groups exposed to cold-restraint stress were similar and much higher than that of the unrestrained sham-operated group (P<0.001). Also, mean hematocrit readings in all groups exposed to cold-restraint stress were lower than in the control group (P<0.05). There was a correlation between severity of mucosal lesions and hematocrit reading (r S =0.57,P<0.001). The results obtained allow the following conclusions: (1) Bile reflux is not necessary for formation of cold-restraint stress lesions in the rat. (2) Hematocrit readings appear to be a useful measure of blood loss secondary to experimental mucosal lesions.
Thermoplastic polyurethane elastomers from bio-based poly(δ-decalactone) diols

Bio-based poly(δ-decalactone) is an amorphous, low glass transition temperature (Tg) material and it is an aliphatic polyester (Martello et al., ACS Macro Lett., 2011) that can be utilized as a soft segment in thermoplastic polyurethanes (TPU). We describe the synthesis and purification of low molar mass poly(δ-decalactone) diols (PdDL), as well as the synthesis and characterization of new PdDL-based TPUs. The PdDLs obtained were characterized by proton nuclear magnetic resonance (1H-NMR) spectroscopy and matrix-assisted laser desorption ionization mass spectroscopy. Three different PdDLs were prepared and their molar masses calculated from 1H-NMR spectroscopy were: Mn ≈ 1300, 1800 and 2700 g mol−1. These three PdDLs were reacted with 4,4′-methylenebis(phenyl isocyanate) and two different chain extenders (1,4-butanediol and water), to synthesize polyester-based TPUs. The TPUs made from PdDLs with Mn of 1800 and 2700 exhibit good elastomeric properties and their Tg values are around −40 °C. With water as chain extender urea bonds were created, which gave TPUs with higher modulus, higher stress at break and lower hysteresis.
Abstinent Alcoholics Exhibit an Exaggerated Stress Response to 2‐Deoxy‐D‐Glucose Challenge

Chronic excessive alcohol consumption can significantly disturb the hypothalamic control of glucose metabolism; however, the mechanism and clinical significance of this disturbance are poorly understood. We used 2-deoxy-D-glucose (2-DG), which produces intracellular glucoprivation, to compare neurochemical, physiological, and behavioral responses to glucoprivic stress between alcoholics abstinent for 3 weeks and healthy volunteers. Twenty-six male alcoholics and 15 male healthy volunteers received intravenous infusions of placebo, 12.5 mg/kg, and 25.0 mg/kg of body weight of 2-DG over 30 min on three separate days, following a random-ordered, double-blind procedure. Minimal effects were observed following administration of the 12.5 mg/kg of body weight dose of 2-DG. Following 25.0 mg/kg, alcoholics showed both exaggerated ACTH and cortisol responses and greater increases in caloric intake when compared with controls. Although anxiety, desire to consume alcohol, plasma progesterone, and sympathetic and adrenal medullary activity all increased following 2-DG, these responses did not differ between alcoholics and controls. The present findings suggest certain specificity for the exaggerated hypothalamic and adrenocortical responses to mild glucoprivic stress in 3-week-abstinent alcoholics.
Preliminary results of an experimental study of the effects of mysid predation on estuarine zooplankton community structure

In a shallow estuarine system near Beaufort, North Carolina, a period of high winter abundance of the mysids Mysidopsis bigelowi and Neomysis americana was associated with a change in zooplankton species composition, from dominance by Acartia tonsa to dominance by Centropages spp. and Saphirella sp. Both mysids feed on A. tonsa at higher rates than the other copepods. Experiments were carried out in 600–1 000 liter enclosures, in which the initial mysid density was manipulated and the effects on the enclosed copepod community were monitored. Mysid predation had a significant effect on copepod densities. The effects of mysid predation on species composition appeared to depend on the relationship between their prey preferences and the dominant copepod species present in the communities. Under conditions favoring dominance by A. tonsa, the preferred prey species, the results suggested that mysid predation may reduce dominance and increase diversity. But when the less preferred Centropages was dominant, mysid predation had no effect on species composition.
Quantitative evaluation of the pentylenetetrazol—Anticonvulsant interaction on the egg of the cat

Abstract The interaction of pentylenetetrazol (PTZ) with the anticonvulsants phenobarbital (PB), trimethadione (TD) and diphenylhydantoin (DPH) or saline on the EEG of the cat was examined with the aid of power spectral density analysis. Pretreatment with PB or TD effectively increased the dose of PTZ required for induction of paroxysmal activity, while some decrease in PTZ dose was seen with DPH pretreatment. A direct correlation was seen between the amplitude (normalized total power) increases and the amount of PTZ required to induce paroxysm with each pretreatment. Dominant hippocampal theta (4.0–4.5 Hz) which was induced by PTZ following saline or DPH pretreatment was reduced or eliminated following TD and PB pretreatments. The triggering of generalized and sustained bilateral seizural activity was suggested to occur because activity in multiple intermittent foci throughout the brain gradually build up to a necessary critical mass. PB and TD were suggested to act by increasing the critical mass required for triggering the paroxysm, while DPH was suggested to act by lowering the critical mass resuling in less severe ictal activity.
A-Current Expression is Regulated by Activity but not by Target Tissues in Developing Lumbar Motoneurons of the Chick Embryo

The functional expression of A-type K+ channels (IA) was examined in chick lumbar motoneurons (LMNs) at embryonic days 6 and 11 (E6 and E11). We observed a threefold increase in IA density between ...
Point Defect Injection and Enhanced Sb Diffusion in Si During Co-Si and Ti-Si Reactions

The effects of Co and Ti silicide film formation on diffusion of buried Sb-doped layers in Si have been investigated. Sb profile analysis by secondary ion mass spectrometry shows that greatly enhanced, non-uniform Sb diffusion occurs during reactions of various thicknesses (30- 300 nm) of Co and Ti by rapid thermal annealing. A simple non-equilibrium intrinsic diffusion model is invoked to estimate time-averaged excess vacancy concentrations. Vacancy concentrations of about 107 times equilibrium values are shown to exist during CoSi2 formation by reaction of a 30 nm Co film at 700°C for 5 min in Ar.Diffusion enhancements at large distances from silicide stripe edges are observed by bevel and etch techniques. These effects tend to decrease with increasing annealing time, indicating that film stresses may play an important role in the interfacial point defect injection process.
Hostile Corporate Takeovers: Why and How Their Numbers Grow

Hostile corporate acquisitions, which were virtually non‐existent a decade ago, have currently become one of the most publicized types of business transactions. Rumors about takeovers have had an enormous impact on stock market trading volume and price behavior for the past several years. This paper traces the legal, regulatory, and financial developments of the 1980s which have created an environment favorable to hostile takeovers, and it discusses controversial behaviors of corporate acquirers and defenders.
Investigation of a Chemiluminescent System for the Determination of Ammonia by Flow-Injection Analysis

Abstract A novel system for the determination of ammonia based on the chemiluminescent reaction between hypochlorite and luminol is presented. The technique of flow injection analysis was employed to automate the system. Ammonia reacts with hypochlorite to form monochloramine in basic solution which decreases the observed chemiluminescence intensity. Several interferents are identified, and the reasons why they interfere are discussed. The effects of interferents are Minimized through the use of a double-tube dialyzer where the ammonia is diffused across the dialyzer membrane into a recipient stream of hydrochloric acid.
Maternal smoking in early childhood: a risk factor for bronchial responsiveness to exercise in primary-school children.

The relationship between maternal smoking and bronchial hyperresponsiveness as assessed by a standardized free running test was investigated in a cohort of 1812 primary-school children in first grade. A child's exposure to maternal smoking during pregnancy, the first year of life, and the study year was recorded. Current exposure was not positively associated with bronchial hyperresponsiveness. The prevalence of this disorder was higher when maternal smoking during the child's first year of life was reported (9%) than when it was not (5.9%). The odds of being hyperresponsive were significantly higher in children exposed to maternal smoking in their first year of life (odds ratio, 2.82; 95% confidence interval, 1.25 to 6.34; p p
Non–Contrast-Enhanced MR Imaging of the Renal Arteries

In this article, we focus on non-contrast magnetic resonance angiography techniques for evaluating renal artery imaging. Time-of-flight, phase contrast, steady-state free procession, and arterial spin labeling are discussed.
LIM-Based Algorithms for the Transient Simulation of Large Networks

An overview of the latency insertion method (LIM) is presented in this paper. Extensions and improvements of the LIM formulation are discussed and techniques that exploit the versatility of the algorithm are compared. It is shown that the algorithm can be extended to simulate frequency-dependent networks. In addition, block partitioning and parallelization methods can further enhance the speed of the algorithm.
An elastic network model of HK97 capsid maturation

The structure of the capsid of bacteriophage HK97 has been solved at various stages of maturity by crystallography and cryo-electron microscopy, and has been reported previously in the literature. Typically the capsid assembles through polymerization and maturation processes. Maturation is composed of proteolytic cleavages to the precursor capsid (called Prohead II), expansion triggered by DNA packaging (in which the largest conformational changes of the capsid appear), and covalent cross-links of neighboring subunits to create the mature capsid called Head II. We apply a coarse-grained elastic network interpolation (ENI) to generate a feasible pathway for conformational change from Prohead II to Head II. The icosahedral symmetry of the capsid structure offers a significant computational advantage because it is not necessary to consider the whole capsid structure but only an asymmetric unit consisting of one hexamer plus an additional subunit from an adjacent pentamer. We also analyze normal modes of the capsid structure using an elastic network model which is also subject to symmetry constraints. Using our model, we can visualize the smooth evolution of capsid expansion and revisit in more detail several interesting geometric changes recognized in early experimental works such as rigid body motion of two compact domains (A and P) with two refolding extensions (N-arm and E-loop) and track the approach of the two particular residues associated with isopeptide bonds that make hexagonal cross-links in Head II. The feasibility of the predicted pathway is also supported by the results of our normal mode analysis.
Moving from ‘things to do on Monday’ to student learning: physical education professional development facilitators' views of success

Background: Facilitation within successful professional development (PD) requires individuals working with a cadre of teachers to examine and reframe their practices, navigating the complexities associated with educational reform initiatives. Although much has been written about the magnitude of the shift required of teachers within current reform, little is known about the changes necessary of facilitators as they make their practice more responsive to the demands of the current reform era.Purpose: The overall purpose of this research project was to examine an international group of facilitators' collective knowledge and experience with ongoing physical education PD. The research question guiding this study was: what constitutes successful PD from the perspective of program facilitators?Theoretical framework: Teacher change theory was used to examine facilitators' conceptions of successful PD.Participants and setting: Participants included 13 experienced PD facilitators chosen because of their experience...
Factors that influence the stability of self-assembled organothiols on gold under electrochemical conditions

Abstract Several factors contribute to the loss and retention of self-assembled monolayers, SAMs, of organothiols at gold electrodes under potential control in 0.1 M tetrabutylammonium hexafluorophosphate in acetonitrile and methylene chloride. Near 0 V vs. Ag/AgCl (saturated KCl), SAMs of dodecanethiol have maximum stability. Under driest and most oxygen-free conditions at negative potentials, such as −1.8 V, SAMs exhibit a 90% loss in surface coverage in 1 h in methylene chloride and in less than 1 min in acetonitrile. At more positive potentials such as + 0.8 V, the rate of SAM loss is slower, and only ca. 33% of surface-confined molecules were removed after l h in methylene chloride, but 100% after 10 min in acetonitrile. Although the rates of removal are different for the two solvents, the potential window of greatest stability is similar, centered near 0 V and extending to −1.0 V and +0.5 V. This window is independent of the type of gold substrate: Au/Cr/glass, Au/(3-mercaptopropyl)trimethoxysilane/glass, and Au foil. In both solvent systems, water greatly diminishes the stability of the surface-bound species at negative and positive potentials. The addition of oxygen, however, greatly enhances the stability of the surface-bound species. Details of the mechanisms for the effect of oxygen and water are not known at this time. However, positive potentials (+ 0.7 V) cause formation of gold oxide, which increases with water concentration. At negative potentials (− 1.5 V) reduction of residual oxygen is facilitated by the presence of water and may form OH− that interacts with SAMs. Stirring under both argon-purged and oxygenated conditions at negative potentials diminishes SAM stability; this is thought to be explained by enhanced flux of either water to the surface or desorbed species away from the surface. Uncompensated resistance and shifts in liquid junction potentials of the reference electrode do not explain differences in potential-dependent SAM stability between the two solvents.