cssi/SciSciGPT-SciSciNet huggingface dataset:
Factors Associated with Never Being Screened for Colorectal Cancer

Colorectal cancer (CRC) screening is underused in the United States, and non-adherence with screening recommendations is high in some populations. This study describes the characteristics of people who have never been screened for CRC. In addition, we use the health belief model to examine the constructs associated with screening behavior. We used data from the 2010 Behavioral Risk Factor Surveillance System (BRFSS) to create three study outcomes: people who have been screened for CRC and are up-to-date with current recommendations, people who have been screened but are not up-to-date, and people who have never been screened. We used multivariate logistic regression modeling to calculate predicted marginal estimates examining the associations between the screening outcomes and demographic and Health Belief Model (HBM) characteristics. Overall 29 % of respondents had never been screened for CRC. In the adjusted model, 36.6 % of US adults age 50–59 years and 29.1 % of US men reported never being screened for CRC. More Asian/Native Hawaiian/Pacific Islander, non-Hispanics (38.2 %) reported never being screened than members of other racial and ethnic groups. Nearly 37 % of people with less than a high school diploma reported never being screened. We found statistically significant differences among screening outcomes for all demographics and HBM constructs except could not see a doctor because of costs in the last 12 months, where approximately 29 % reported no CRC screening. New interventions should focus on those subpopulations that have never been screened for CRC.
Strength and toughness of carbon fiber reinforced aluminum matrix composites

Abstract Two sets of aluminum matrix composites reinforced with both uncoated and SiC-coated Pitch-55 aligned carbon fibers were prepared having a volume fraction f =0.2 of reinforcement to test certain toughening strategies proposed earlier (A.S. Argon and V. Gupta, in G.K. Haritos and O.O. Ochoa (eds.), Damage and Oxidation Protection in High Temperature Composites , Vol. 25-2, ASME, New York, 1991, p. 1). Preparatory studies showed that the Pitch-55 fibers are damaged to some degree as a result of composite sample preparation. The loss of strength in the SiC-coated fibers was much less than in the uncoated fibers. Tensile tests of both smooth and precraked composite sheets showed that while the composites reinforced with SiC-coated carbon fibers were stronger than the composites reinforced with uncoated fibers, the former had less than half the tensile toughness of the latter. The higher tensile toughness of the composites with uncoated fibers is a direct result of the more extensive debonding of fibers from the matrix during fiber fracture. This permits the formation of a thicker fracture process zone in the composites reinforced with uncoated fibers. The measured composite strength values and their trends were consistent with the predictions of theory (P.M. Scop and A.S. Argon, J. Composite Mater., 3 (1969) 30). The different tensile toughness of the composites with the coated and uncoated fibers could be accounted for by simple fracture models of fiber composites incorporating the beneficial effects of controlled debonding of fibers.
Reducing Bias in Observational Studies Using Subclassification on the Propensity Score

Abstract The propensity score is the conditional probability of assignment to a particular treatment given a vector of observed covariates. Previous theoretical arguments have shown that subclassification on the propensity score will balance all observed covariates. Subclassification on an estimated propensity score is illustrated, using observational data on treatments for coronary artery disease. Five subclasses defined by the estimated propensity score are constructed that balance 74 covariates, and thereby provide estimates of treatment effects using direct adjustment. These subclasses are applied within sub-populations, and model-based adjustments are then used to provide estimates of treatment effects within these sub-populations. Two appendixes address theoretical issues related to the application: the effectiveness of subclassification on the propensity score in removing bias, and balancing properties of propensity scores with incomplete data.
Comparison of different experimental techniques for determination of elastic properties of solids

Abstract Four different experimental techniques, namely resonant ultrasound spectroscopy (RUS), impulse excitation (IE), nanoindentation (NI) and four-point bending (4PB) test were used to determine the Young’s and shear moduli of 99.9% pure Al2O3, 7075 aluminum, 4140 steel and Pyrex glass. The results from the different tests are compared and statistically analyzed to determine the precision of each method and to estimate the significance of the differences among the four techniques. It was found that dynamic methods (RUS and IE) have superior precision and repeatability when compared to NI and 4PB for all four tested materials. It was also found that the differences between results of RUS and IE are not statistically significant, and that NI can be equally successfully used for determining Young’s modulus of well-prepared, microstructurally homogenous and relatively hard materials. 4PB was found to have the lowest precision and repeatability among the four test methods.
Misfit strain phase diagrams of epitaxial PMN–PT films

Misfit strain–temperature phase diagrams of three compositions of (001) pseudocubic (1 − x)·Pb (Mgl/3Nb2/3)O3 − x·PbTiO3 (PMN–PT) thin films are computed using a phenomenological model. Two (x = 0.30, 0.42) are located near the morphotropic phase boundary (MPB) of bulk PMN–PT at room temperature (RT) and one (x = 0.70) is located far from the MPB. The results show that it is possible to stabilize an adaptive monoclinic phase over a wide range of misfit strains. At RT, the stability region of this phase is much larger for PMN–PT compared to barium strontium titanate and lead zirconate titanate films.
Endogenously Generated Hydrogen Peroxide Is Required for Execution of Melphalan-Induced Apoptosis as Well as Oxidation and Externalization of Phosphatidylserine

Hydrogen peroxide (H(2)O(2)) is generated endogenously during execution of both intrinsic as well as extrinsic apoptotic programs suggesting that it may function as a secondary messenger in apoptotic pathways. In the present study, we investigated the role of endogenously generated H(2)O(2) by using two cell lines-HL-60 cells and its subclone, H(2)O(2) resistant HP100 cells overexpressing catalase (CAT). With the exception of CAT, we found no differences in the expression of other primary antioxidant enzymes (Cu/Zn-superoxide dismutase, Mn-superoxide dismutase, and glutathione peroxidase) or apoptosis-related proteins (Bcl-2 and Bax) in HP100 cells as compared with the parental HL-60 cells. Production of H(2)O(2) was readily detectable as early as 1 h after melphalan (Mel) exposure of HL-60 cells but not HP-100 cells. Biomarkers of apoptosis, such as release of cytochrome c, disruption of mitochondrial transmembrane potential, caspase-3 activation, and chromatin condensation, became apparent much later, 3 h and onward after Mel treatment of HL-60 cells. The emergence of essentially all biomarkers of apoptosis was dramatically delayed in HP100 cells as compared with HL-60 cells. A relatively minor phospholipid species, phosphatidylserine (PS), was markedly oxidized 3 h after Mel treatment in HL-60 cells (but not in HP100 cells) where it was significantly inhibited by exogenously added CAT. The two most abundant classes of membrane phospholipids, phosphatidylcholine and phosphatidyletanolamine, did not undergo any significant oxidation. PS oxidation took place 3 h after exposure of HL-60 cells to Mel and paralleled the appearance of cytochrome c in the cytosol. Neither cytochrome c release nor PS oxidation occurred in Mel-treated HP100 cells, indicating that both endogenous H(2)O(2) and cytochrome c were essential for selective PS oxidation detected in HL-60 cells. Mel-induced PS oxidation was also associated with externalization of PS on the surface of HL-60 cells. Given that 3-amino-1,2,4-triazole, a CAT inhibitor, suppressed the resistance of HP100 cells to apoptosis, production of reactive oxygen species, PS oxidation, and PS externalization induced by Mel, the results from the present study suggest that H(2)O(2) is critical for triggering the Mel-induced apoptotic program as well as PS oxidation and externalization.
Improved ocean measurement capabilities using advanced engineering technology

Ocean measurement systems for the 1980's will require improved capabilities to sample and measure specific ocean parameters. With the increasing costs of ocean operations, these systems must be designed and produced to yield a higher degree of performance and reliability than has been previously available. Also, new capabilities will be required as program emphasis shifts to the continental shelves and margins where the understanding of coastal processes, energy development and production, ocean waste disposal, and improved water quality are of increasing social and economic importance. Some of the requirements for improved marine measurement systems and how they can be achieved are discussed below.
Impact of mandibular condyle preservation on patterns of failure in head and neck cancer.

Objective To determine the role of native condyle preservation in local recurrence after segmental mandibulectomy in patients with head and neck squamous cell carcinoma. Methods Retrospective chart review with main outcome measuring local control of cancer. Results Between 1994 and 2003, 72 patients (48 men, 24 women) with an average age of 73.5 years without previous treatment underwent segmental mandibulectomy. Fifty-four cases (n = 54) involved the mandible posterior to the mental foramen and are the subject of this review. In 36 patients, the condyle was preserved and mandibular continuity was restored. In 18 patients, condyle and ramus were resected without mandibular reconstruction. Reconstructive modalities included primary closure (3), split-thickness skin graft (3), pedicle flap (19), and free tissue reconstructions (29). Overall local-regional recurrence rate was 22 percent (12 of 54); no recurrences were identified in patients who underwent condylar resection. Recurrences were observed in patients with mandibular reconstruction by both plate and pedicle flap (5 of 9) or (osteo) myocutaneous free flap (7 of 27). Conclusion Condylar preservation may predispose patients to local recurrence after segmental mandibulectomy. This does not translate into overall reduction in survival.
Long paths through four vertices in a 2-connected graph

Let G be a 2-connected graph, let u and v be distinct vertices in V(G), and let X be a set of at most four vertices lying on a common (u, v)-path in G. If deg(x) ≥ d for all x e V(G) \ {u, v}, then there is a (u, v)-path P in G with X ‚ V(P) and |E(P)| ≥ d. © 2000 John Wiley & Sons, Inc. J Graph Theory 33: 5565, 2000
Neither Race nor Gender Influences the Usefulness of Amino-Terminal Pro-Brain Natriuretic Peptide Testing in Dyspneic Subjects: A ProBNP Investigation of Dyspnea in the Emergency Department (PRIDE) Substudy

Abstract Background Amino-terminal pro-brain natriuretic peptide (NT-proBNP) is useful for the diagnosis and exclusion of congestive heart failure (HF). Little is known about the effect of race on NT-proBNP concentrations. Also, NT-proBNP levels may be higher in apparently well women, but the effect of gender on NT-proBNP concentrations in dyspneic patients is not known. Methods and Results NT-proBNP (Elecsys proBNP, Roche, Indianapolis, IN) was measured in 599 dyspneic patients in a prospective study. Of these, 44 were African American; 295 were female. NT-proBNP levels were examined according to race and gender in patients with and without acute HF using analysis of covariance. Receiver operating characteristic (ROC) curves assessed NT-proBNP by race and gender. Cutpoints for diagnosis (450, 900, and 1800 pg/mL for ages 75 years) and exclusion (300 pg/mL) were examined in African-American and female subjects. There was no difference in the rates of acute HF between African-American and non–African-American (30% versus 35%, P = .44) or male and female (35% versus 35%, P = .86) subjects. In subjects with HF, there was no difference in median NT-proBNP concentrations between African American and non–African American (6196 versus 3597 pg/mL, P = .37). In subjects without HF, unadjusted NT-proBNP levels were lower in African-American subjects than in non–African-American subjects (68 versus 148 pg/mL, P P = .53) or without HF (116 pg/mL versus 150 pg/mL, P = .62). Among African Americans, NT-proBNP had an area under the ROC for acute HF of 0.96 ( P P Conclusion NT-proBNP is useful for the diagnosis and exclusion of acute HF in dyspneic subjects, irrespective of race or gender.
Bone marrow studies in patients suffering from infections and receiving chloramphenicol.

SUMMARY The bone marrow of 45 patients suffering from various infections and receiving chloramphenicol, was examined morphologically. Infection alone depressed erythropoiesis in 6 patients. Two patients developed depression of erythropoeiesis while receiving chloramphenicol. One patient developed erythroid hypoplasia ten days after chloramphenicol had been discontinued. Chloramphenicol used in therapeutic doses for a relatively short period of time, is not associated with a high incidence of bone marrow morphological abnormalities.
Electronic Structure of Adenine and Thymine Base Pairs Studied by Femtosecond Electron-Ion Coincidence Spectroscopy

Femtosecond pump-probe spectroscopy was combined with photoelectron-photoion coincidence detection to investigate the electronic structure and dynamics of isolated adenine (A) and thymine (T) dimers and the adenine-thymine (AT) base pair. The photoelectron spectra show that pipi* and npi* states are only weakly perturbed in the hydrogen-bound dimers as compared to the monomers. For cationic base pairs with internal energies greater than 1 eV, we observed considerable cluster fragmentation into protonated monomers. This process selectively removed signals from the npi* --> n-1 ionization channel in all dimers. The photoelectron spectra are compared to time-resolved mass spectra and confirm the assignment of short-lived pipi* and npi* populations in the adenine, thymine, and mixed AT dimers.
An autoregulatory feedback loop involving PAP1 and TAS4 in response to sugars in Arabidopsis

miR828 in Arabidopsis triggers the cleavage of Trans-Acting SiRNA Gene 4 (TAS4) transcripts and production of small interfering RNAs (ta-siRNAs). One siRNA, TAS4-siRNA81(−), targets a set of MYB transcription factors including PAP1, PAP2, and MYB113 which regulate the anthocyanin biosynthesis pathway. Interestingly, miR828 also targets MYB113, suggesting a close relationship between these MYBs, miR828, and TAS4, but their evolutionary origins are unknown. We found that PAP1, PAP2, and TAS4 expression is induced specifically by exogenous treatment with sucrose and glucose in seedlings. The induction is attenuated in abscisic acid (ABA) pathway mutants, especially in abi3-1 and abi5-1 for PAP1 or PAP2, while no such effect is observed for TAS4. PAP1 is under regulation by TAS4, demonstrated by the accumulation of PAP1 transcripts and anthocyanin in ta-siRNA biogenesis pathway mutants. TAS4-siR81(−) expression is induced by physiological concentrations of Suc and Glc and in pap1-D, an activation-tagged line, indicating a feedback regulatory loop exists between PAP1 and TAS4. Bioinformatic analysis revealed MIR828 homologues in dicots and gymnosperms, but only in one basal monocot, whereas TAS4 is only found in dicots. Consistent with this observation, PAP1, PAP2, and MYB113 dicot paralogs show peptide and nucleotide footprints for the TAS4-siR81(−) binding site, providing evidence for purifying selection in contrast to monocots. Extended sequence similarities between MIR828, MYBs, and TAS4 support an inverted duplication model for the evolution of MIR828 from an ancestral gymnosperm MYB gene and subsequent formation of TAS4 by duplication of the miR828* arm. We obtained evidence by modified 5′-RACE for a MYB mRNA cleavage product guided by miR828 in Pinus resinosa. Taken together, our results suggest that regulation of anthocyanin biosynthesis by TAS4 and miR828 in higher plants is evolutionarily significant and consistent with the evolution of TAS4 since the dicot—monocot divergence.
Carnitine palmitoyltransferase activities (1 and 2) and the rate of palmitate oxidation in liver mitochondria from diabetic rats

Abstract The effects of diabetes and insulin replacement on the rate of hepatic mitochondrial long-chain fatty acid oxidation were investigated with specific reference to the activity of carnitine palmitoyltransferases (1 and 2) and to oxidative phosphorylation. In liver mitochondria from ketotic diabetic rats, the overall rate of [U-14C]palmitate oxidation in the presence of carnitine was elevated 50–70% when compared with mitochondria from control rats. Carnitine-independent oxidation, which comprised 15–20% of the total was also increased in these mitochondria. Both carnitine palmitoyl-transferase (1 and 2) activities were increased 50–70% in these mitochondria. There was a 40% increase in oxygen uptake with palmitate under state 3 conditions in mitochondria from liver of ketotic diabetic rats. At state 4 the rate of oxygen uptake by these mitochondria was increased to an even greater extent. This resulted in low respiratory control ratios associated with a moderate increase of base-line and Mg2+-stimulated ATPase activity. In nonketotic diabetic rats, carnitine palmitoyltransferase (1 and 2) activities were also increased; however, these mitochondria did not show the “loosely” coupled respiration found in the ketotic diabetic rats. These findings indicate that the overall rate of long-chain fatty acid oxidation in liver mitochondria and specifically, carnitine palmitoyltransferase (1 and 2) activities can be regulated by insulin. An enhanced rate of long-chain fatty acid oxidation in liver mitochondria both at state 3 and 4 appeared to be a significant feature of diabetic ketosis.
Probit analysis of market participants' attitudes toward selected market alternatives for us farmers' stock peanuts

Attitudes of producers and buyers of farmers' stock peanuts toward different market alternatives were analyzed assuming the absence of the government support program. A multivariate probit model was used to ascertain profiles of producers favoring the private treaty market and the proposed organized markets. Results indicate that computerization of the private treaty market might serve as a basis for implementation of an organized market for farmers' stock peanuts.
ON THE ROLE OF HELIX 0 OF THE TRYPTOPHAN SYNTHETASE ALPHA CHAIN OF ESCHERICHIA COLI

The role of helix 0 of the alpha chain (TrpA) of the tryptophan synthetase alpha2beta2 multi-functional enzyme complex of Escherichia coli was examined by deleting amino-terminal residues 2-6, 2-11, or 2-19 of TrpA. Selected substitutions were also introduced at TrpA positions 2-6. The altered genes encoding these polypeptides were overexpressed from a foreign promoter on a multicopy plasmid and following insertion at their normal chromosomal location. Each deletion polypeptide was functional in vivo. However all appeared to be somewhat more labile and insoluble and less active enzymatically than wild type TrpA. The deletion polypeptides were overproduced and solubilized from cell debris by denaturation and refolding. Several were partially purified and assayed in various reactions in the presence of tryptophan synthetase beta2 (TrpB). The purified TrpADelta2-6 and TrpADelta2-11 deletion polypeptides had low activity in both the indole + serine --> tryptophan reaction and the indoleglycerol phosphate + serine --> tryptophan reaction. Poor activity in each reaction was partly due to reduced association of TrpA with TrpB. The addition of the TrpA ligands, alpha-glycerophosphate or indoleglycerol phosphate, during catalysis of the indole + serine --> tryptophan reaction increased association and activity. These findings suggest that removal of helix 0 of TrpA decreases TrpA-TrpB association as well as the activity of the TrpA active site. Alignment of the TrpA sequences from different species indicates that several lack part or all of helix 0. In some of these polypeptides, extra residues at the carboxyl end may substitute for helix 0.
A discussion of: “Biotite melting in high-grade metamorphic gneisses from the Haut-Allier (French Massif Central)” by Nédélec and Paquet

N6d61ec and Paquet (N. and P.) (1981) examined high-grade pelitic gneisses from the Precambrian and Hercynian HautAllier Massif in France. They noted the presence, in their samples, of an "amorphous" phase which they interpret as glass representing quenched melt formed by partial melting of biotite. N. and P. have made a creditable attempt to integrate TEM and Raman spectroscopic studies with classical petrological techniques. However, after examination of the mineralogical, textural, chemical and spectroscopic evidence presented in their paper, we disagree with the conclusions drawn by N. and P. regarding biotite "melting". Figure 5a of N. and P. shows an electron diffraction pattern of diffuse rings taken by them to indicate an amorphous phase in their original sample. Without further supporting evidence this is not necessarily correct. It is wellknown that samples in electron beam experiments may easily become amorphous due to beam damage. This is especially true of samples that are poorly-crystallized and hydrous and when high accelarating voltages are used. It is of interest that randomly-oriented crystallites of kaolinite were found in some regions of the "glass" (Fig. 5b; N. and P.). Those "crystallites" could correspond to bettercrystallized areas or areas with less beam damage. Here we discuss the textural, mineralogical and spectroscopic observations of N. and P. and show that their "amorphous" material is consistent with altered cordierite rather than glass derived from partial melting. Biotite in the rocks is commonly corroded and sur
Mutagens and potential mutagens in the biosphere I. DDT and its metabolites, polychlorinated biphenyls, chlorodioxins, polycyclic aromatic hydrocarbons, haloethers

Abstract For a proper assessment of actual risks, it is essential that the interactions between different modes of administration of a toxicant be understood and that the probable impingement of the environmental substances upon the various portals of entry be known. To best understand this last requirement we must know how the toxicants in question are distributed in and are transported through the environment to finally impact on man. In this review, we have attempted to evaluate but a small number of mutagens and potential mutagens ( e.g. , DDT and its metabolites, polychlorinated biphenyls, chlorinated dioxins, polycyclic aromatic hydrocarbons and haloethers) in terms of their occurrence, use patterns, distributions and impact in the environment. In many cases, the information is fragmentary. For example, patterns of region and local variation of the toxicants have been only superficially investigated and the detailed pathways of residues within the trophic networks are poorly understood. The physiological and ecological effects of the toxicants at sub-lethal levels are also to a large extent unknown. We must have more information as to (1) the production (nature of reactants, amounts, reactivity, disposal, etc.), import and export data for specific potential environmental toxicants, (2) the nature and routes of their global transport, and (3) the concentration, longevity, biochemical and toxicological activity of their residues (including specific chemical nature) that occur in their various biosphere compartments including air, water, soil, and biota.
D₁-NMDA receptor interactions in the rat nucleus accumbens change during adolescence

Many aspects of the dopamine (DA) system mature during adolescence. For example, the DA modulation of glutamate responses in the rat prefrontal cortex (PFC) acquires adult characteristics during late adolescence. In the striatum, D₁ receptors modulate NMDA responses, but whether this behaviorally important interaction matures during adolescence is not known. Here, we tested whether the D₁ agonist SKF38393 affects NMDA actions on nucleus accumbens medium spiny neuron (MSN) excitability in slices from juvenile and young adult rats. NMDA dose-dependently increased excitability in both age groups, and the D₁ agonist produced a marginal increase of MSN excitability. In juvenile slices, the most common interaction was a downregulation of NMDA effects on excitability by the D₁ agonist, whereas in most adult MSN, the D₁ agonist increased NMDA effects on MSN excitability. These results suggest that D₁-NMDA receptor interactions in the nucleus accumbens change during adolescence, a change that may result in different processing of reward functions during this critical developmental stage.
Major basic protein as a marker of malignant potential in trophoblastic neoplasia.

Abstract OBJECTIVE: We tested whether serum pregnancy-associated major basic protein levels distinguish between benign and malignant trophoblastic disease. STUDY DESIGN: We compared serum pregnancy-associated major basic protein levels in seven patient groups: nonpregnant and pregnant controls, partial moles, complete moles, persistent moles, placental-site trophoblastic tumors, and choriocarcinoma. RESULTS: The results showed that patients with partial and complete moles had elevated serum pregnancy-associated major basic protein levels comparable to normal pregnancy. In contrast, patients with persistent mole, placental-site trophoblastic tumors and choriocarcinoma had low median serum levels comparable to those of the nonpregnant controls. Significant differences were shown between the complete and persistent mole groups (p = 0.0001) and between the complete mole group and the choriocarcinoma group (p = 0.0001); however, persistent moles were indistinguishable from choriocarcinoma (p = 0.2010). CONCLUSION: Serum pregnancy-associated major basic protein levels thus distinguish between benign disorders, such as pregnancy and partial and complete moles, and trophoblastic tumors, such as persistent moles and choriocarcinoma. The absence of elevated serum levels of pregnancy-associated major basic protein may be useful clinically to indicate a more aggressive or frankly malignant tumor. (Am J Obstet Gynecol 1996;175:632-7.)
Hepatitis C Virus Genotyping: Interrogation of the 5′ Untranslated Region Cannot Accurately Distinguish Genotypes 1a and 1b

Although the 5′ untranslated region (5′ UTR) is the most conserved region of the hepatitis C virus (HCV) genome, it has been suggested that interrogation of this region is sufficient for determination of the HCV genotype. We compared two methods of determination of the HCV genotype: (i) direct sequencing of the DNA of the NS-5b region and (ii) reverse line probe assay (LiPA; INNO-LiPA HCV II; Innogenetics N.V.) of the 5′ UTR. There was 100% concordance between the two methods for genotype but only 80% concordance for subtype. A significant percentage of genotype 1a isolates were misclassified by LiPA as genotype 1b. Sequence analysis revealed that the only consistent difference in the 5′ UTR for these genotype 1a isolates misclassified as genotype 1b was a single nucleotide (A/G) at position −99 of the HCV genome. All isolates with discordant results analyzed had a G at this position, consistent with LiPA determination of these samples as subtype 1b. However, sequence analysis of 222 nucleotides in the NS-5b region clearly identified all of these isolates as subtype 1a. Population distribution data from the University of Pittsburgh Medical Center of over 200 samples analyzed by sequencing of the NS-5b region and over 1,000 samples analyzed by LiPA also indicated that INNO-LiPA HCV II cannot accurately differentiate HCV genotype 1a isolates from HCV genotype 1b isolates. We provide evidence that the A/G at position −99 represents a sequence polymorphism in the HCV genome that cannot differentiate subtype 1a from subtype 1b isolates. In conclusion, the 5′ UTR is not heterogeneous enough for use in determination of the HCV subtype and cannot be used for differentiation of HCV genotypes 1a and 1b.
Comparison of Different Phonon Transport Models for Predicting Heat Conduction in Silicon-on-Insulator Transistors

The problem of self-heating in microelectronic devices has begun to emerge as a bottleneck to device performance. Published models for phonon transport in microelectronics have used a gray Boltzmann transport equation (BTE) and do not account adequately for phonon dispersion or polarization. In this study, the problem of a hot spot in a submicron silicon-on-insulator transistor is addressed. A model based on the BTE incorporating full phonon dispersion effects is used. A structured finite volume approach is used to solve the BTE. The results from the full phonon dispersion model are compared to those obtained using a Fourier diffusion model. Comparisons are also made to previously published BTE models employing gray and semi-gray approximations. Significant differences are found in the maximum hot spot temperature predicted by the different models. Fourier diffusion underpredicts the hot spot temperature by as much as 350% with respect to predictions from the full phonon dispersion model. For the full phonon dispersion model, the longitudinal acoustic modes are found to carry a majority of the energy flux. The importance of accounting for phonon dispersion and polarization effects is clearly demonstrated.
Laparoscopic right living donor nephrectomy.

Abstract Introduction Left laparoscopic donor nephrectomy (LDN) is preferred over right LDN due to technical ease. The purpose of this study was to compare results between right and left LDN and thereby determine whether substantial experience with right LDN can provide results equivalent to left LDN. Methods All LDN from 2000 to 2004 were reviewed, and right LDN data compared to left LDN data. Statistical analyses included chi-square and Student t tests. Results Two hundred thirteen left LDN (84%) were compared to 40 right LDN (16%). Donor age, gender, race, and body mass index, and multiple arteries were similar in right and left LDN groups. Operative and cold ischemia times were similar, but warm ischemia was longer for right LDN (3:55 ± 1:22 minutes) than left LDN (3.18 ± 1:06 minutes; P = .004). Despite this, renal allograft function was similar on postoperative day 7 (creatinine 1.77 ± 1.21 for right LDN, 1.7 ± 1.5 for left LDN) and at 1 year (right LDN 1.5 ± 0.4, left LDN 1.23 ± 0.28). Graft survival rate in the right LDN at 1 year was 97.5%. Conclusions This large experience with right LDN indicates that results comparable to left LDN can be obtained. This observation increases the options for LDN in patients with multiple left renal arteries, or with right renal cysts, or with right kidneys that are smaller in size compared to the contralateral left kidney.
Comparison of motion and stereo methods in passive ranging systems

The authors compare the estimates in passive ranging systems using motion and stereo approaches. It is shown that an integrated approach is necessary to provide better range estimates over a field-of-view (FOV) of interest in helicopter flight. The recursive approach for processing a sequence of stereo images, described together with a recursive motion algorithm (RMA), provides the basis for an integrated method to provide more accurate range information. Results based on motion sequences of stereo images are presented. >
The Use of Stimulant Medication and Behavioral Interventions for the Treatment of Attention Deficit Hyperactivity Disorder: A Survey of Parents’ Knowledge, Attitudes, and Experiences

We examined parents’ knowledge, attitudes, and information sources regarding Attention-Deficit/Hyperactivity Disorder (ADHD), including treatment with stimulant medication and behavioral interventions. Responses from parents with a child diagnosed with ADHD and parents without a child diagnosed with ADHD were also compared. Participants consisted of 146 parents of elementary age children from Wisconsin. The surveyed parents were aware of issues surrounding ADHD and the use of stimulant medication, but there were several areas where they possessed inaccurate or incomplete factual information. Parents who had a child diagnosed with ADHD rated the effects of stimulant medication more positively and side effects as less severe than other parents. They also rated behavioral interventions as less effective on all questions. Implications of the study are discussed.
The behaviour of children at home who were severely malnourished in the first 2 years of life.

Studies of school age children who were severely malnourished in infancy have focused primarily on somatic growth and intelligence, but information about behaviour is almost completely lacking. In this study the social behaviour of 71 Jamaican school boys who were severely malnourished in infancy (index subjects) is compared with that of classmates of the same age and sex (comparisons) and also with the nearest sibling of the same sex where available. The child's behaviour in his home setting was assessed through an interview with the child's parent or parent substitute. It was found that the index children differed significantly from their comparisons in several ways. They were less liked by siblings and more unhappy at school. They more often behaved immaturely, were more clumsy and were either more highly active or lethargic. They were also more often withdrawn, solitary or unsociable. Differences between index boys and their siblings were not statistically significant on individual questions but were in the same direction as the index-comparision differences. No relationship was found between the age when admitted to hospital for malnutrition and later behaviour. Examination of the aetiological role of malnutrition and other biological and social factors is the next step in the present study.
Metabolism of arachidonate and stearate injected simultaneously into the mouse brain.

The metabolism of a polyunsaturated and a saturated fatty acid in brain membrane phosphoglycerides was examined by injecting simultaneously a mixture of14C-arachidonate and3H-stearate into the mouse brain and isolating the microsomal and synaptosomal fractions at 1–40 min after injections. Both types of labeled fatty acids were utilized more readily in the microsomal than the synaptosomal fractions in brain. However, labeled arachidonate was incorporated more rapidly into membrane phosphoglycerides than was stearate. In both subcellular fractions, the relative specific radioactivity (3H and14C) of diacyl-glycerophosphorylinositol (diacyl-GPI) was higher than other types of phosphoglycerides such as diacyl-glycerophosphorylcholine (diacyl-GPC) and diacyl-glycerophosphorylethanolamine (diacyl-GPE). Furthermore, the apparent rates of incorporation of radioactivity into diacyl-GPI was more rapid for the14C-arachidonate than for the3H-stearate. Results of the experiment have demonstrated obvious differences in metabolism between stearate and arachidonate in brain. The more rapid transfer of arachidonate to diacyl-GPI is probably due to the presence of an acyl transferase system specially active for the transfer of arachidonyl groups to diacyl-GPI.
Buffon's Coin Problem and beyond.

Summary This article describes an investigation of Buffon's coin problem and related problems with the aid of an applet. The problems are accessible at a variety of grade levels and facilitate making connections between geometry and probability.
Insights into the complete and partial photooxidation of black carbon in surface waters.

Increasing wildfire activity in the Alaskan Arctic may result in new sources of black carbon (BC) to arctic watersheds. Black carbon, primarily comprised of condensed aromatics, is one of the most chemically recalcitrant fractions of organic carbon. However, lateral transfer of particulate and dissolved BC from soils to sunlit surface waters is increasingly suggested to result in the photochemical mineralization of BC to CO2. While sunlight can also partially photooxidize aromatic compounds in surface waters, producing compounds with a higher O/C than the parent compound, this degradation pathway has not yet been identified for either particulate or dissolved BC. To address knowledge gaps on the photochemical degradation of particulate and dissolved BC, we quantified the complete and partial photooxidation of particulate and dissolved BC derived from arctic biomass as photochemical CO2 production and O2 consumption relative to dark controls. Concurrently, we investigated shifts in the chemical composition of dissolved BC following exposure to sunlight using UV-visible absorbance, fluorescence spectroscopy, and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). The chemical and physical properties of BC produced from charring arctic biomass were similar to BC produced by wildfires in terrestrial ecosystems based on elemental analysis and FT-ICR MS. Based on the concentration of light-absorbing carbon in each fraction, dissolved BC was disproportionately more susceptible to complete and partial photooxidation compared to particulate BC. Upon exposure to sunlight, the predominant fate of dissolved BC was partial photooxidation, while a smaller fraction of dissolved BC was photomineralized to CO2. Shifts in both the optical and mass spectrometry spectra suggested that condensed aromatics likely comprised the fraction of dissolved BC that was completely and partially photooxidized. To further refine the meaning of sunlight as a sink for aquatic BC, the reactivity of partially oxidized photoproducts of BC in the aquatic organic carbon pool must be determined.
Quo vadis, Rampart One?

Summary When viewed in terms of the European model, it is clear that the paramedic movement in this country arose as the logical consequence of physicians' abdication of responsibility — their failure to do the job they were mandated to do: to render care to the sick and injured wherever those patients might be. For whatever reasons, American physicians — unlike their European colleagues — will not work on ambulances. So by default, the task went to paramedics. Unfortunately, there has been a subsequent tendency to forget that the paramedic has no a priori authority to function, let alone practice medicine. Unlike the nurse, he is not even independently licensed. On the contrary, his function is wholly derivative. He derives his sanction entirely from the license of a physician for whom he is supposed to act as proxy in certain clearly defined and strictly controlled activities. We have by default, assigned to the paramedic certain aspects of care of the critically ill and injured. Whether it is appropriate to have delegated the care of this vulnerable patient group is another question. The fact is, we have chosen to do so. But this should not mean that we also delegate the moral responsibility for the welfare of those patients. Somewhere in our retreat from the patient, we must stop and retrench. We, as physicians, bear responsibility for what happens to patients out on the streets, they are our patients. And each of us should make certain that those patients are receiving the same quality of care we ourselves would deliver were we physically present. This means that every physician in the community must be involved in the emergency medical services system, must be informed regarding the policies, standards and practices operating on the streets of his city. And it means that Rampart One must be willing to make a total commitment to quality control of his system. He must be willing to go out on the ambulances and monitor firsthand the activities of the paramedics; to review every case report; to obtain follow-up information on patient outcome; to insist that paramedic skills be periodically reviewed and recertified. He must not trade off medical standards for political expediency or make compromises in the quality of medical care in order to placate special interest groups or to spare himself the work of constant surveillance. These are not hypothetical issues Regrettably, we are already accumulating ample evidence from many MICU systems throughout the country of what happens when medical control falls to physicians who are too indolent or not concerned enough to monitor closely what is happening in the prehospital setting. Rampart One is not a game. It has been said that the individual lying in the street is, until he comes under a physician's care, a victim, a patient. If this is true, it is because we have made him so. He is the victim of American medicine and its He is the victim of the carnival atmosphere that currently pervades so much of prehospital emergency care. He is the victim of every physician who would abdicate responsibility for the lives of others. He deserves much better.
Flame and surface structure of laminate propellants with coarse and fine ammonium perchlorate

The combustion of two-dimensional laminate propellants of ammonium perchlorate (AP) and hydroxyl-terminated polybutadiene is investigated experimentally and theoretically. The experiments use UV emission and transmission imaging to obtain simultaneous information about flame structure and burning-surface profile for pressures ranging from 2 to 55 atm. Previous experimental work for laminates with pure binder has been extended to cases including laminates with oxygenated binder. The modeling uses numerical computations based on finite-rate chemistry with simplified kinetics and a free surface. Results show that flame-surface structure is a function of length scale (in this case, fuel-layer thickness), pressure, and equivalence-ratio disparity between the nonpremixed fuel and the oxidizer regions (binder-matrix equivalence ratio). Factors that promote split (diffusion) flame-surface structure are large length scale, high pressure, and large equivalence-ratio disparity. The opposite factors (including oxygenating the binder) promote merged (premixed) flame-surface structure. For oxygenated binder loaded to the monomodal-AP limit (fine-AP/binder 76/24) the transition thickness between split and merged structure is 5 to 10 times larger than that for pure binder. A correlation is shown between this transition and the optimal thickness that maximizes regression rate (at a given pressure). It has been determined both computationally and experimentally through the use of triple-layer laminates that the flame-surface structure at the center of the laminate is relatively uninfluenced by the outer boundary conditions. This provides firm justification for using the simpler, single-fuel-layer laminates to validate computational simulations through characterizing the effects of pressure, thickness, and binder equivalence ratio on flame and burning-surface structure.
The role of M1 muscarinic cholinergic receptors in the discriminative stimulus properties of N-desmethylclozapine and the atypical antipsychotic drug clozapine in rats.

Rationale The discriminative stimulus properties of clozapine (CLZ) have been studied for decades because it remains the prototype for atypical antipsychotic drug effects and yet is unique in many ways, including increased efficacy in treatment-resistant schizophrenia and in reducing suicidality. Recent studies have indicated that the active CLZ metabolite N-desmethylclozapine (NDMC) may play a role in mediating the cognitive efficacy of CLZ and may also have atypical antipsychotic properties.
Cnidocil apparatus: sensory receptor of Physalia nematocytes

The cnidocil apparatus, a cluster of subcellular structures at the external surface of the nematocytes of Physalia physalis , was examined by scanning and transmission electron microscopy. The cnidocil apparatus consists of a modified cilium or cnidocil surrounded by 15 to 21 stereocilia. The stereocilia contain closely packed, longitudinally arranged microfilaments. The cnidocil contains numerous singlet and doublet microtubules that lack the classical 9 + 2 microtubule pattern characteristic of most cilia and flagella. The basal body of the cnidocil does, however, maintain the usual circle of nine triplets of microtubules. It is proposed that the cnidocil of the nematocyte is truly the sensory receptor for mechanical and chemical stimuli that elicit nematocyst discharge.
Global Environmental Law and Treaty-Making on Hazardous Substances: The Minamata Convention and Mercury Abatement

In global environmental cooperation, legally binding agreements remain a customary way for states to set common goals and standards. This article analyzes the Minamata Convention on Mercury by addressing three questions: First, how did linkages to earlier agreements shape the negotiations? Second, what were the main legal and political issues during the negotiations? Third, what are the major issues moving forward with treaty implementation and mercury abatement? The analysis shows that the decision to start treaty negotiations was influenced by related policy developments on hazardous chemicals as well as differences in national interests. Five sets of issues dominated the negotiations: 1) supply and trade, 2) products and processes, 3) emissions and releases, 4) artisanal and small-scale gold mining, and 5) resources and compliance. The article concludes that future mercury abatement hinges on the parties' ability to move beyond the initial mandates, as the convention may affect decisions by a wide rang...
PREVALENCE OF AVIAN HEMATOZOA IN CENTRAL VERMONT

Peripheral blood smears from 1,547 birds, of 50 species, from 15 families trapped in Northfield, Vermont were examined for hematozoa. Numerous new host–parasite relationships were identified. The prevalence of all species of parasites over the 3 yr of the study was 42.5%. Prevalence of the genera of parasites were: Leucocytozoon—36.5%; Trypanosoma—7.3%; Haemoproteus—6.3%; microfilariae—1.0%; Plasmodium—1.0%. Peak prevalence (78.9%) occurred in the first half of July. Peak intensity was seen in the last half of June. Evidence from immature birds suggested that active transmission of all genera of hematozoans took place in the study area. Leucocytozoon gametocytes, unlike Haemoproteus gametocytes, were detected in smears from birds during all seasons of the year, and showed no period of complete remission. Trypanosoma and microfilariae also were seen throughout the year.
Annotated bibliography: Psychosocial aspects of AIDS on the professional caregiver.

The effect of education on nurses’ perception of AIDS Armstrong-Esther, C. and Hewitt, W.E. Department of Sociology, University of Western Ontario, London, Ontario N6A5C2, Canada. Journal of Advanced Nursing 1516 (1990) 638-651 This paper examines changes in health workers’ perceptions of AIDS accruing from attempts at professional enlightenment. Based upon a 4-month study of 60 registered nurses enrolled in a bachelor of nursing programme, it investigates alterations in knowledge and attitudes resulting from intense instruction on AIDS and AIDS patient care as part of a class epidemiology. Contrary to what much of the literature has suggested to this point, regarding knowledge enhancement and attitudinal transformation, the research reveals a number of positive changes to have occurred over the period of the study. Not only were the nurses better informed about AIDS than previously, but their attitude towards the disease and patient care had become considerably more liberal.