cssi/SciSciGPT-SciSciNet huggingface dataset:
Separation of metallic residues from the dissolution of a high-burnup BWR fuel using nitrogen trifluoride

Abstract Nitrogen trifluoride (NF3) was used to fluorinate the metallic residue from the dissolution of a high burnup, boiling water reactor fuel (∼70 MWd/kgU). The washed residue included the noble-metal phase (containing ruthenium, rhodium, palladium, technetium, and molybdenum), smaller amounts of zirconium, selenium, tellurium, and silver, along with trace quantities of plutonium, uranium, cesium, cobalt, europium, and americium, likely as their oxides. Exposing the noble metal phase to 10% NF3 in argon, between 400 and 550 °C, removed molybdenum and technetium near 400 °C as their volatile fluorides, and ruthenium near 500 °C as its volatile fluoride. The events were thermally and temporally distinct and the conditions specified provide a recipe to separate these transition metals from each other and from the nonvolatile residue. Depletion of the volatile fluorides resulted in substantial exothermicity. Thermal excursion behavior was recorded with the thermal gravimetric instrument operated in a non-adiabatic, isothermal mode; conditions that typically minimize heat release. Physical characterization of the noble-metal phase and its thermal behavior are consistent with high kinetic velocity reactions encouraged by the nanoparticulate phase or perhaps catalytic influences of the mixed platinum metals with nearly pure phase structure. Post-fluorination, only two products were present in the residual nonvolatile fraction. These were identified as a nano-crystalline, metallic palladium cubic phase and a hexagonal rhodium trifluoride (RhF3) phase. The two phases were distinct as the sub-μm crystallites of metallic palladium were in contrast to the RhF3 phase, which grew from the parent, nano-crystalline noble-metal phase during fluorination, to acicular crystals exceeding 20-μm in length.
Temperature-related Cauchy–Born rule for multiscale modeling of crystalline solids

In this study, we develop a temperature-related Cauchy–Born (TCB) rule for multiscale modeling of crystalline solids based on the assumptions that deformation is locally homogeneous and atoms have the same local vibration mode. When employing the TCB rule in the nanoscale continuum approximation, the first Piola–Kirchhoff stress can be explicitly computed as the first derivative of the Helmholtz free energy density to the deformation gradient. Since the Helmholtz free energy is temperature-dependent, multiscale methods consisting of the TCB rule embedded continuum model can be used to elucidate temperature-related physical phenomena at the nanoscale. Stress analyses of canonical ensembles verify the continuum approximation with the TCB rule by comparing the calculated Cauchy stresses with the outcomes of molecular dynamics simulations. As an application of the TCB rule in multiscale modeling, the nanoscale meshfree particle method with the TCB rule demonstrates the same crack propagation phenomenon in a nanoplate as molecular dynamics. This example shows that the temperature effects are significant on the crack propagation speed when the temperature is in a particular range.
Shape optimization of cold-formed steel columns

Abstract The objective of this paper is to demonstrate the application of formal optimization tools towards maximizing the compressive strength of an open cold-formed steel cross section. In addition, in the work presented here the cross section shape is not limited by pre-determined elements (flanges, webs, stiffeners, etc.), as is commonly required to meet the necessity of conventional code-based procedures for design that employ simplified closed-form stability analysis. Instead, by utilizing the finite strip method for stability analysis and the Direct Strength Method for the strength calculation, the full solution space of cold-formed steel shapes may be explored. In the analysis herein, a given width of sheet steel is allowed to be bent at 20 locations along its width, thus providing the ability to form nearly any possible shape. Three optimization algorithms are explored: the gradient-based steepest descent method and two stochastic search methods, genetic algorithms and simulated annealing. Compared with a standard cold-formed steel lipped channel the final optimized capacities are found to be more than double the original design. Steepest descent solutions are shown (as expected) to be highly sensitive to the initial guess, but they provide symmetrical and conceptually clean solutions. The stochastic search methods require significantly more computational capacity, explore the solution space more fully, and generate solutions that are largely insensitive to the initial guess. For long and intermediate length cold-formed steel columns the optimization methods identify two non-conventional alternative designs that maximize capacity. The future of this work lies in further integrating the optimization methods with additional manufacturing and construction constraints; for now, the method suggests several interesting alternative cross sections that are worthy of future study.
Surface free energy and polarity of organic pigments

Abstract The surface free energy and polarity values of a number of organic pigments are obtained from contact angle measurements and the interfacial tension equation of Wu(1). The pigment types studied are phthalocyanine, quinacridone, toluidine red, isoindolinone, indanthrone, β-oxynaphthoic acid derivative, and thioindigoid red. The surface free energies obtained agree reasonably well with those predicted from parachor and density values.
Inhibition and reconstitution of Ah receptor transformation in vitro: role and partial characterization of a cytosolic factor(s).

Abstract The Ah receptor binds 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and related aryl hydroearbons and mediates their biochemical and toxic effects by modifying gene expression. In order to interact with DNA, the TCDD · receptor complex must undergo a poorly understood transformation to a form which is distinguishable by its increased affinity for DNA-Sepharose and for its specific enhancer element upstream from the cytochrome P450IA1 gene. We have found that this transformation process is inhibited in vitro by treatment of rat hepatic cytosol with activated charcoal prior to addition of [3H]TCDD. The transformed form of the receptor can be generated in the charcoal-inhibited cytosol by incubation with hepatic cytosol from either DBA/2J mice (in which [3H]TCDD-specific binding is undetectable under these conditions) or rat (in which Ah receptor was prebound with unlabeled ligand). Transformation is observed whether this addition occurs before or after [3H]TCDD is bound to the charcoal-treated receptor. Thus, transformation is (i) mediated by some additional cytosolic component(s) and (ii) separable from ligand binding. The untransformed [3H]TCDD · receptor complex, isolated by DNA-Sepharose chromatography, can also be transformed if DBA mouse hepatic cytosol is added. This partially purified untransformed receptor preparation and gel retardation analysis were used to further characterize the transforming activity in DBA cytosol. We observed that the “Ah receptor transforming factor” is heat-labile, trypsin-sensitive, removed or inactivated by charcoal, of greater than ~50 kDa, and elutes from Superose at a Rs of ~6 nm. In conjunction with our previous studies documenting the increased molecular weight of the transformed compared to the untransformed Ah receptor, and identifying the heteromeric structure of the transformed receptor, we postulate that the ligand-binding subunit (the untransformed receptor) must associate tightly with another cytosolic protein, which is also present in the receptor-defective DBA mouse, in order to transform to the transcriptionally active receptor.
Recurrence of Anal Adenocarcinoma After Local Excision and Adjuvant Chemoradiation Therapy: Report of a Case and Review of the Literature

Tumors arising from the anal canal are rare, comprising 1.5% of all gastrointestinal tumors in the USA. The vast majority of these anal cancers are epidermoid (cloacogenic/basaloid and squamous cell carcinomas), while adenocarcinomas reportedly occur 5% to 19% of the time. Because of its rarity, reports about anal adenocarcinoma are limited to small retrospective studies and case reports. Moreover, no series has directly compared outcomes between patients undergoing the various available treatment options, making it difficult to determine the optimal treatment for this aggressive cancer. Current management of this cancer remains controversial, with some authors believing abdominoperineal resection with permanent colostomy should be considered the standard treatment. Others propose that combined chemoradiation be adopted as a possible treatment in certain patients. We describe a case of recurrent anal adenocarcinoma after conservative management with local excision and adjuvant chemoradiation therapy.
Eye tracking for visualization evaluation: reading values on linear versus radial graphs

An eye tracking methodoLogy can help uncover subtLe cognitive processing stages that are otherwise difficult to observe in visuaLization evaLuation studies. Pros and cons of eye tracking methods are discussed here, incLuding common analysis metrics. One example metric is the initial time at which all elements of a visualization that are required to complete a task have been viewed. An illustrative eye tracking study was conducted to compare how radial and Linear graphs support value Lookup tasks for both one and two data-dimensions. Linear and radial versions of bar, Line, area, and scatter graphs were presented to 32 participants, who each completed a counterbalanced series of tasks. Tasks were completed more quickly on Linear graphs than on those with a radial Layout. Scanpath analysis revealed that a three-stage processing] find desired data dimension, [2] find its datapoint, and [3] map the datapoint to its value. Mapping a datapoint to its value was slower on radial than Linear graphs, probably because eyes need to follow a circular, as opposed to a Linear path. Finding a datapoint within a dimension was harder using Line and area graphs than bar and scatter graphs, possibly due to visual confusion of the Line representing a data series. ALthough few errors were made, eye tracking was also used here to classify error strategies. As a result of these analyses, guidelines are proposed for the design of radial and Linear graphs.
A Comparison of Behavioral and Emotional Functioning in Children and Adolescents with Autistic Disorder and PDD-NOS

Behavioral symptomatology was compared in 26 children and adolescents with Autistic Disorder ("autism") and 25 children and adolescents with Pervasive Developmental Disorder, Not Otherwise Specified ("PDD-NOS"). Relative to individuals with PDD-NOS, those with autism had more symptoms of depression, social withdrawal, atypical behavior, and immature social skills--and fewer family problems. These differences remained even when group differences in intellectual ability were statistically controlled. No group differences emerged in somatization, anxiety, or hyperactivity. Findings suggest that although both groups demonstrate considerable evidence of behavioral and emotional problems, those with autism are at particularly high risk for comorbid behavioral and emotional disabilities.
Intra-arterial Chemotherapy for Retinoblastoma in 70 Eyes: Outcomes Based on the International Classification of Retinoblastoma

Objective To analyze our 5-year experience of intra-arterial chemotherapy (IAC) for retinoblastoma as primary or secondary therapy. Design Retrospective interventional case series. Participants A total of 70 eyes of 67 patients. Intervention Ophthalmic artery chemotherapy infusion under fluoroscopic guidance was performed using melphalan (3, 5, or 7.5 mg) in every case, with additional topotecan (1 mg) and/or carboplatin (30 or 50 mg) as necessary. Main Outcome Measures Tumor control and treatment complications. Results The mean patient age at IAC was 30 months. The treatment was primary in 36 eyes and secondary in 34 eyes. Those primary therapy eyes were classified according to the International Classification of Retinoblastoma (ICRB) as group A (n = 0), B (n = 1), C (n = 4), D (n = 17), or E (n = 14). The secondary therapy eyes had failed previous intravenous chemotherapy (n = 34) in every case. Each eye received a mean of 3 IAC sessions per eye (median, 3; range, 1–7 sessions). After IAC with a mean follow-up of 19 months, globe salvage was achieved in 72% of primary-treated cases and in 62% of secondary-treated cases. Specifically, primary therapy achieved globe salvage for group B (100%), group C (100%), group D (94%), and group E (36%). Of all 70 eyes, complete regression was achieved for solid tumor in 48 of 51 eyes (94%), subretinal seeds in 40 of 42 eyes (95%), and vitreous seeds in 34 of 39 eyes (87%). After each catheterization (n = 198), the main complications included transient eyelid edema (5%), blepharoptosis (5%), and forehead hyperemia (2%). More lasting complications included vitreous hemorrhage (2%), branch retinal artery obstruction (1%), ophthalmic artery spasm with reperfusion (2%), ophthalmic artery obstruction (2%), partial choroidal ischemia (2%), and optic neuropathy ( Conclusions Five-year experience with IAC indicates that this technique is remarkably effective for the management of retinoblastoma as both a primary and a secondary treatment.
Artifacts in oral biopsy specimens.

Abstract The problem of artifacts introduced into biopsies of oral tissue are discussed. The different types of artifacts are described and illustrated, and suggestions for prevention are given.
3-Deoxy-D-manno-octulosonate-8-phosphate synthase catalyzes the C-O bond cleavage of phosphoenolpyruvate.

The mechanism of 3-deoxy-D-manno-octulosonate-8-phosphate (KDO8P) synthase was investigated. When [18O]-PEP specifically labeled in the enolic oxygen is a substrate for KDO8P synthase, the 18O is recovered in Pi. This indicates that the KDO8P synthase reaction proceeds with C-O bond cleavage of PEP similar to that observed in the 3-deoxy-D-arabino-heptulosonate-7-phosphate synthase catalyzed condensation of PEP and erythrose-4-phsophate (1). No evidence for a covalent enzyme-PEP intermediate could be obtained. No [32P]-Pi exchange into PEP nor scrambling of bridge 18O to non-bridging positions in [18O]-PEP was observed in the presence or absence of arabinose-5-phosphate or its analog ribose-5-phosphate. Bromopyruvate inactivated KDO8P synthase in a time dependent process. It is likely that bromopyruvate reacts with a functional group at the PEP binding site since PEP, but not arabinose-5-phosphate, protects against inactivation.
The short-term effects of feedback on accuracy of urine glucose determinations in insulin dependent diabetic children

Self-monitoring of urine glucose concentrations is a basic component of selfregulation of serum glucose in juvenile diabetics. However, previous research has shown that patient determinations of glucose concentrations are often inaccurate. This study assessed the effects of feedback training versus extended practice on accuracy of urine testing in a sample of juvenile diabetic youngsters selected for inaccurate testing. Results showed a significant decrease in error rate in subjects trained with feedback, as compared to those in the extended practice control group.
Activities of Polar Bodies of Cerebratulus

1. Die Polkorperchen vonCerebratulus lacteus Verrill zeigen bemerkenswerthe Filarerscheinungen, die mit ahnlichen bei gewissen Protozoen in Vergleich gebracht werden konnen. 2. Die Filarthatigkeit beginnt bald nach der Ausstosung der Polarkorperchen; indem sie unter progressiven Merkmalen an Ausdehnung zunimmt, erreicht sie einen gewissen endgultigen Typus. 3. Die Filarthatigkeit des ersten Polkorperchens ist in durchaus charakteristischer Weise von der des zweiten verschieden. 4. Die Polkorperchen bleiben dem Ei angelagert bis sich seine Cilien entwickeln; unter sich selbst bleiben sie zusammengelagert, bis man sie im Larvalstadium aus den Augen verliert. 5. Die Verbindung der Polkorperchen unter einander und mit dem Ei geschieht durch eine Substanz, die wegen ihrer Gesammteigenschaften und wegen ihrer Filarerscheinungen fur lebendes Protoplasma zu halten ist. Diese Verbindung ist in ihrem Wesen auf die ursprungliche Kontinuitat zwischen Ei und Polkorperchen zuruckzufuhren, — eine Kontinuitat, die entweder unverandert weiterbestand, oder stets erneut und modificirt wurde. 6. Die Filarthatigkeit dieser Polkorperchen ist charakteristisch verschieden von derjenigen, die man bei Echinodermen beobachten kann: aber beide konnen in ihrer Ursache auf Protoplasmathatigkeit zuruckgefuhrt werden. 7. Die gefundenen Thatsachen unterstutzen die Hypothese, dass »filose« Erscheinungen jeder lebenden Masse zukommen.
Self versus non-self discrimination during CRISPR RNA-directed immunity

All immune systems must distinguish self from non-self to repel invaders without inducing autoimmunity. Clustered, regularly interspaced, short palindromic repeat (CRISPR) loci protect bacteria and archaea from invasion by phage and plasmid DNA through a genetic interference pathway. CRISPR loci are present in approximately 40% and approximately 90% of sequenced bacterial and archaeal genomes, respectively, and evolve rapidly, acquiring new spacer sequences to adapt to highly dynamic viral populations. Immunity requires a sequence match between the invasive DNA and the spacers that lie between CRISPR repeats. Each cluster is genetically linked to a subset of the cas (CRISPR-associated) genes that collectively encode >40 families of proteins involved in adaptation and interference. CRISPR loci encode small CRISPR RNAs (crRNAs) that contain a full spacer flanked by partial repeat sequences. CrRNA spacers are thought to identify targets by direct Watson-Crick pairing with invasive 'protospacer' DNA, but how they avoid targeting the spacer DNA within the encoding CRISPR locus itself is unknown. Here we have defined the mechanism of CRISPR self/non-self discrimination. In Staphylococcus epidermidis, target/crRNA mismatches at specific positions outside of the spacer sequence license foreign DNA for interference, whereas extended pairing between crRNA and CRISPR DNA repeats prevents autoimmunity. Hence, this CRISPR system uses the base-pairing potential of crRNAs not only to specify a target, but also to spare the bacterial chromosome from interference. Differential complementarity outside of the spacer sequence is a built-in feature of all CRISPR systems, indicating that this mechanism is a broadly applicable solution to the self/non-self dilemma that confronts all immune pathways.
Preparation of Dicke states in an ion chain

We have investigated theoretically and experimentally a method for preparing Dicke states in trapped atomic ions. We consider a linear chain of $N$ ion qubits that is prepared in a particular Fock state of motion $|m⟩$. The $m$ phonons are removed by applying a laser pulse globally to the $N$ qubits and converting the motional excitation to $m$ flipped spins. The global nature of this pulse ensures that the $m$ flipped spins are shared by all the target ions in a state that is a close approximation to the Dicke state $|{D}_{N}^{(m)}⟩$. We calculate numerically the fidelity limits of the protocol and find small deviations from the ideal state for $m=1$ and $m=2$. We have demonstrated the basic features of this protocol by preparing the Bell state $|{D}_{2}^{(1)}⟩$ in two ${^{25}\text{M}\text{g}}^{+}$ target ions trapped simultaneously with an ${^{27}\text{A}\text{l}}^{+}$ ancillary ion.
A multiple access scheme for multimedia traffic in wireless ATM

This paper proposes a multiple access scheme for the forthcoming wireless ATM(Asynchronous Transfer Mode) system. Such ATM compatible wireless systems are motivated by the rapidly increasing demand for wireless extensions to broadband networks, which are expected to support mixed broadband services including Constant Bit Rate (CBR), Variable Bit Rate (VBR), and Available Bit Rate (ABR) traffic. Since these different traffics have very different performance requirements, the multiple access scheme design is very challenging. In this paper, we propose a multiple access scheme called Dynamic Time Division Multiple Access with Piggybacked Reservation (DTDMA/PR), attempting to achieve higher statistical multiplexing efficiency in the mixed VBR/CBR/ABRtraffic scenario. The basic idea is to exploit two levels of reservation. The first level deals with the isochronous nature of CBR and VBR traffic and the bursty nature of ABR traffic by using the ALOHA reservation procedure. The second level exploits the piggybacked reservation approach to cope with the dynamic feature of VBRtraffic in order to increase the multiplexing efficiency. An analytical model is also developed in this paper and verified by simulation. Numerical examples are given to gain some insight into the protocol itself.
The Makings of Personhood in a Shelter for People Considered Homeless and Mentally III

This paper is about the pragmatic makings of identity and personhood in a Boston shelter for people considered homeless and mentally ill. Drawing upon the philosophical writings of Amelie Rorty, it examines the ways in which the words and actions of shelter residents and staff effected certain discourses of selfhood and personhood. In the course of their everyday engagements with staff and others, residents took the form of or were quietly depicted as, variably constituted "characters," "individuals," "figures," "persons," or "selves." Differentials of power were crucial to such dialogic constructions, for many of the residents' presentations of self developed in rhetorical, tactical response to the dominant imageries advanced by others.
Nuclear Polarization of He 3 Gas by Metastability Exchange with Optically Pumped Metastable He 3 Atoms

A small fraction of metastable He/sup 3/ is maintained, by means of a r- f discharge, in He/sup 3/ in a magnetic field. The metastable atoms are partially polarized by optical pumping using a 1- mu V circularly polarized pumping light. Further, however, the stable and metastable atoms are capable of exchanging excitations; in the exchange reactions, the outgoing stable atoms may have magnetic quantum numbers differing by unity from those of the ingoing stable atoms. Thus spin-flip operators connecting the stable and metastable atoms are introduced, and the exchange reactions have the effect of polarizing the stable ground-state atoms. Nuclear polarizations of 0.8 and 3.5% are obtained at room temperature at pressures of 10 and 1 man Hg respectively. Nuclear magnetic resonance studies of ground-state and 3/sub s1/ He/sup 3/ atoms are also reported. (T.F.H.)
Purification and characterization of a basic protein from the stratum corneum of mammalian epidermis.

Abstract A basic protein has been isolated and purified from the stratum corneum of newborn rat epidermis. This protein is referred to as stratum corneum basic protein. It was purified by ion-exchange chromatography on DE-52 and CM-52 cellulose. The protein has a molecular weight of 50 000 on sodium dodecyl sulfate-polyacrylamide gels. It is composed of one polypeptide chain and contains no detectable carbohydrate. The protein has an isoelectric point in the range of pH9–10, but decomposes during isoelectric focusing giving rise to a polypeptide of less than 10 000 daltons. Amino acid analysis reveals high quantities of glutamic acid, glycine, serine, arginine and relatively high levels of histidine, with these five amino acids composing 74% of the total residues. The amino acid analysis is very similar to histidine-containing keratohyalin proteins isolated from the granular layer of epidermis by several investigators. The stratum corneum basic protein differs from fibrous proteins isolated from the same cell layer with respect to net charge, amino acid composition, and molecular weight. The protein does not react with antibody to the fibrous protein. The basic protein has properties which are consistent with its possible function as a stratum corneum interfilamentous matrix protein.
Expression profiling of 519 kinase genes in matched malignant peripheral nerve sheath tumor/plexiform neurofibroma samples is discriminatory and identifies mitotic regulators BUB1B , PBK and NEK2 as overexpressed with transformation

About 50% of all malignant peripheral nerve sheath tumors (MPNSTs) arise as neurofibromatosis type 1 associated lesions. In those patients malignant peripheral nerve sheath tumors are thought to arise through malignant transformation of a preexisting plexiform neurofibroma. The molecular changes associated with this transformation are still poorly understood. We sought to test the hypothesis that dysregulation of expression of kinases contributes to this malignant transformation. We analyzed expression of all 519 kinase genes in the human genome using the nanostring nCounter system. Twelve cases of malignant peripheral nerve sheath tumor arising in a background of preexisting plexiform neurofibroma were included. Both components were separately sampled. Statistical analysis compared global changes in expression levels as well as changes observed in the pairwise comparison of samples taken from the same surgical specimen. Immunohistochemical studies were performed on tissue array slides to confirm expression of selected proteins. The expression pattern of kinase genes can separate malignant peripheral nerve sheath tumors and preexisting plexiform neurofibromas. The majority of kinase genes is downregulated rather than overexpressed with malignant transformation. The patterns of expression changes are complex without simple recurring alteration. Pathway analysis demonstrates that differentially expressed kinases are enriched for kinases involved in the direct regulation of mitosis, and several of these show increased expression in malignant peripheral nerve sheath tumors. Immunohistochemical studies for the mitotic regulators BUB1B, PBK and NEK2 confirm higher expression levels at the protein level. These results suggest that the malignant transformation of plexiform neurofibroma is associated with distinct changes in the expression of kinase genes. The patterns of these changes are complex and heterogeneous. There is no single unifying alteration. Kinases involved in mitotic regulation are particularly enriched in the pool of differentially expressed kinases. Some of these are overexpressed and are therefore possible targets for kinase inhibitors.
Effects of diazepam and picrotoxin on the visual system.

Abstract The effects of diazepam (1 mg/kg i.v.) followed by picrotoxin (0.1 mg/kg i.v.) on the temporal alterations of shock-evoked cortical potentials after a flash of light were investigated in the pretrigeminal cat. In the dark-adapted state, a light flash produced a facilitation of more than 1500 sec, followed by a slight depression of the evoked cortical potential obtained by optic tract stimulation. The administration of diazepam resulted in a marked facilitation of the optic-tract-evoked cortical potential after light stimulation. In the light-adapted state, a light flash produced a large facilitation followed by a depression of the evoked cortical potential obtained by retinal stimulation. Diazepam administration greatly depressed the early post-flash facilitation, but had little effect on the late depression. The administration of picrotoxin after diazepam tended to reverse the effects of diazepam. The results appear to support the hypothesis that optic tract fibers presynaptically inhibit inhibitory interneurons in the lateral geniculate nucleus. A second site of the diazepam and picrotoxin effect is the retina, possibly at axo-axonic synapses between amacrine cells and bipolar cells.
Detection of human papillomavirus DNA in advanced epithelial ovarian carcinoma

Tissue specimens from 10 out of 12 patients with advanced epithelial ovarian adenocarcinoma contained DNA of human papillomavirus type 6 (HPV-6). HPV DNA was identified by in situ hybridization at high stringency using biotin-labeled DNA probes. Nonneoplastic tissue specimens from other pelvic sites of the same patients were also examined. None showed evidence of HPV DNA. The meaning of these findings in relation to epithelial ovarian carcinoma is discussed.
The Role of Friends in Early Adolescents' Academic Self-Competence and Intrinsic Value for Math and English.

In a sample of 207 eighth grade students, we examined similarities between students and their friends in achievement motivation and whether friendship support moderated these associations. Academic self-competence and intrinsic value for math and English were assessed using both perceptions of friends and actual friend reports collected through friend nominations. For both sources of information, there was a stronger positive association between students’ and friends’ academic self-competence when friendships were rated as more supportive. Analyses predicting intrinsic value for math and English provided weaker evidence of an interaction. Comparisons of the students’ perceptions and their friends’ actual reports suggested that students overestimated the degree to which their friends had attitudes similar to their own. Students also perceived that their friends valued academics significantly less than the friends actually reported. Results suggest that both friend and friendship characteristics are important for understanding student achievement motivation.
Networked research: an EC model for U.S.?

The European Community (EC) has found ways to systematically benefit underrepresented minorities and less research-intensive regions through the distribution of research funds. Raising the level of research performance and excellence across Europe is a criterion for receipt of awards from the
Predictors of extended intensive care unit resource utilization following surgery for ovarian cancer

Abstract Objective. To identify perioperative variables associated with length of stay in the surgical intensive care unit (SICU), and overall cost of hospitalization in order to optimize resource utilization among patients undergoing surgery for ovarian cancer. Methods. A retrospective analysis of patients admitted to the SICU immediately after surgery for ovarian cancer between 1/1/94 and 6/30/04 was performed. Patients admitted to the SICU were categorized in two groups. Those admitted for Results. A total of 95 patients were admitted to the SICU immediately after surgical management for ovarian cancer, with 57% requiring a stay ≥48 h. Patient age=63 years was associated with an increase risk of admission to the SICU for ≥48 h (OR: 5.9, 95% CI: 1.72–20.50, p =0.005). Patients with administration of ≥5 l of crystalloid solution during surgery were 8 times more likely to have prolonged admission to the SICU (95% CI: 2.34–27.57, p =0.001). Furthermore, a preoperative serum albumin level ≥3.5 g/dl was associated with a reduction in the risk of prolonged admission to the SICU (OR: 0.23, 95% CI: 0.07–0.77, p =0.02). The average cost of hospitalization per patient was $33,086. Cost of hospital care was strongly associated with SICU length of stay ( p =0.005). Conclusion. Extensive fluid resuscitation during surgery, poor nutritional status, and ≥63 years are associated with a prolonged postoperative SICU stay. These data may facilitate a reduction in unnecessary ICU admissions for patients without these risk factors and thereby optimize resource utilization following surgery for ovarian cancer.
Enhanced mobility of Pb in the presence of dissolved natural organic matter

Abstract The speciation of Pb in batch experiments and its mobility under flowing conditions in column transport experiments were investigated to study Pb behavior in a soil-water system in the presence of dissolved natural organic matter (DOM), peat humic acid (PHA) and peat fulvic acid (PFA). A sandy soil having a significant intraparticle porosity was used as the sorbing media. Batch equilibrium sorption isotherms for single components (Pb, PHA, and PFA) and for Pb in the presence of PHA and PFA were generated. Batch equilibrium experiments were also performed for both PHA and PFA to investigate Pb-DOM binding in the absence of soil. Single component (Pb, PHA, and PFA) and multicomponent (Pb-PHA and Pb-PFA) laboratory-scale column transport experiments were conducted to assess transport behavior of Pb in the presence of DOM. Sorption isotherms indicated that the soil had a higher affinity for PHA than for PFA. However, single component column transport experiments showed that PHA was less retarded than PFA. This anomaly was attributed to the size exclusion of the larger PHA molecules from the intraparticle porosity of the media under the geochemical conditions in the column. Pb retardation predicted by equilibrium equations based upon nonlinear isotherm parameterization agreed well with observed retardation. However, equilibrium retardation equations overpredicted retardation of DOM, indicating sorption kinetic limitations (chemical and/or physical nonequilibrium), molecular size exclusion during column transport, or chemical heterogeneity of the DOM. In multicomponent column transport experiments, Pb retardation decreased by factors of 4–8 in the presence of DOM. Multicomponent batch equilibrium experiments suggested that Pb mobility was governed by speciation of Pb with soluble DOM during transport. Thus, Pb eluted earlier in the presence of PHA than in the presence of PFA because PHA had a higher affinity for Pb binding than PFA.
Metastatic bronchogenic carcinoma masquerading as a felon

This report describes a rare occurrence of a subcutaneous metastatic bronchogenic carcinoma to the distal fingertip. The original clinical presentation suggested an infectious process. Subsequent roentgenograms, sterile cultures, and positive biopsy material revealed that the lesion started as a subcutaneous metastasis that secondarily involved adjacent bone. Amputation of the digit was performed.
A Proof of the Convexity of the Free Boundary for Porous Flow through a Rectangular Dam Using the Maximum Principle.

Abstract : The steady two-dimensional flow is considered under gravity of water from one reservoir to another reservoir through a porous rectangular isotropic homogeneous dam with impervious bottom. Using the maximum principle, a proof of the convexity of the free boundary is given.
Application of MR spectroscopy to the study of tumor biology

Though MR spectroscopy has long been used to analyze the structure of organic compounds in solution, interest in applying it to the study of biologic systems has been slow in evolving because of past problems with spectral resolution in solids and gels. Renewed interest in this area has been stimulated both by the rapid growth of MR imaging as a clinical tool as well as by improvements in MR spectrometer design and use of sophisticated pulse sequences which have greatly improved the analysis of molecular composition. This review specifically focuses on the application of MR spectroscopy to studying the biology of malignant cells. The bulk of MR studies in this area to date have involved either 1H or 31P spectroscopy. Several investigators have now demonstrated that 1H spectra can be used to distinguish both animal and human tumors of differing metastatic properties. Preliminary data suggest that these spectral differences result in part from differences in cell surface glycoproteins and/or glycolipids between cells of low and high metastatic potential. Many of these molecules can absorb cell water potentially affecting T1 of cell water by their relative concentrations. Prolonged T2 relaxation times have been associated with some spectral peaks which distinguish cells of differing metastatic potential. The findings may partly explain why tumors have the prolonged T1 and T2 relaxation times seen in proton MR imaging. Other 1H MR spectroscopic studies suggest that there are detectable differences in plasma lipids in patients with a variety of malignancies compared to normal controls, suggesting possible utility as a screening test.(ABSTRACT TRUNCATED AT 250 WORDS)
Miscibility and biodegradability of blends of poly(lactic acid) and poly(vinyl acetate)

Poly(lactic acid) (PLA) was melt blended with poly(vinyl acetate) (PVA) using a single-screw extruder. The extruded films obtained were characterized for miscibility, physical properties, degradation and surface morphology. Differential scanning calorimetry showed that all the as-extruded films were amorphous, and that the blends were compatible as only one glass transition temperature was observed. Results obtained from physical property testing indicated that the blends exhibit synergism in the range of 5 to 30% PVA, probably due to some interactions taking place in that region. Enzymatic degradation studies showed that there was a vast difference in the weight loss of pure PLA samples and the 95/5 PLA/PVA blend. Surface tension results showed that this was due to the vast difference in the surface tension of the pure PLA films and the 95/5 blend. Deaged-free blends showed the maximum degradation, followed by aged-extruded and then deaged-fixed. Scanning electron micrographs showed that the mode of degradation differs for the aged and deaged samples. A uniform degradation pattern was seen in the case of deaged samples while the aged samples showed a non-uniform pattern of degradation.
Comparing Radioactive and Trephine-Disk Bioassays of Dicloxacillin and Gentamicin in Ocular Tissues in Vitro

Trephined disks of tissue (6 mm diameter) from fresh rabbit eyes were immersed overnight in solutions of radioactive carbon (14C)-dicloxacillin or gentamicin, then assayed by one of two methods: agar-diffusion bioassay, using filter-paper disks immersed in known concentrations of antibiotic as standards, or radioactive assay. The bioassay underestimated the concentrations of antibiotic in sclera and iris by 38 to 72%, and slightly overestimated those in the cornea. A corrected bioassay was calculated, based on the differences in fluid mass between tissue specimens and filter-paper disks; this value was within 20% of the radioactive assay in 18 of 24 experiments with dicloxacillin, and in 14 of 24 with gentamicin. There was evidence of pronounced binding of gentamicin to ocular tissues (iris greater than sclera greater than cornea); this appeared to be a saturable and reversible phenomenon. Less marked binding of dicloxacillin to iris and sclera was noted. The results indicated that, depending on the degree of accuracy required, the corrected trephine-disk agar-diffusion bioassay provides a reasonable estimate of the antibiotic content of ocular tissues.
Resveratrol Prevents Impairment in Activation of Retinoic Acid Receptors and MAP Kinases in the Embryos of a Rodent Model of Diabetic Embryopathy

Diabetes induces impairments in gene expression during embryonic development that leads to premature and improper tissue specialization. Retinoic acid receptors (RARs and retinoid X receptor [RXRs]) and mitogen-activated protein kinases (MAPKs) play crucial roles during embryonic development, and their suppression or activation has been shown as a determinant of the fate of embryonic organogenesis. We studied the activation of RARs and MAPKs in embryonic day 12 (E12) in embryos of rats under normal, diabetic, and diabetic treated with resveratrol ([RSV]; 100 mg/kg body weight) conditions. We found downregulation of RARs and RXRs expressions as well as their DNA-binding activities in the embryos exhibiting developmental delays due to diabetes. Furthermore, the phosphorylation of extracellular signal-regulated kinase (ERK) 1/2 was decreased and phosphorylation of c-Jun N-terminal kinase (JNK) 1/2 and p38 was increased. Interestingly, embryos of diabetic rats treated with RSV showed normalized patterns of RARs, RXRs, neuronal markers, and ERK, JNK and p38 phosphorylation.
Conditioning and power-handling of the cooled graphite limiter on PDX

A single graphite rail limiter was used for high power neutral beam injection experiments on PDX from February to July, 1982. The uncoated water-cooled limiter, with a total area of 800 cm2, performed well in discharges of up to 7 MW of injected power. It was initially conditioned with high power ohmic discharges which removed absorbed and adsorbed impurities. After conditioning, carbon was the primary impurity which evolved from the limiter during high power neutral beam heated discharges. Visible Bremsstrahlung measurements of Zeff were employed to determine the effectiveness of the limiter in maintaining clean plasmas during neutral beam heating and as a measure of the conditioning of the limiter with time. Operation for a period of several months was required to condition the limiter surface to the point where neutral beam injection of 7 MW for 250 ms resulted in only a small rise in Zeff. Thermocouple measurements and a nonlinear cooling model were used to estimate both the absorbed power and the corresponding surface temperatures of the limiter. For the series of discharges studied, the power absorbed by the limiter was found to increase with input power at lower plasma currents, but was almost constant at large plasma current and beam power.
A practical synthesis of (+)‐cocaine

(+)-Cocaine has been prepared from commercially available 3-tropinone in four steps. Synthetic procedures and experimental details are provided.
Transport of potential pollutants in runoff water from land areas receiving animal wastes: A review

Abstract A state-of-the-art review is presented concerning the transport of nutrients (N and P), oxygen demanding compounds (BOD and COD), indicator organisms and pathogens in runoff from land areas receiving animal wastes. Three different land areas are considered: pastures and rangelands, land application sites, and feedlots. For land application sites, results of a linear regression analysis indicated highly significant correlations between constituent (N or P) loading rate and its concentration in runoff water, and also between constituent loading rate and its mass yield rate. Field plots receiving manure during winter and spring, and subject to snowmelt runoff followed a different relationship compared to those receiving applications during summer and fall, and not subject to snowmelt runoff. Effects of various factors, such as time and method of application, soil and cropping management practices, in relation to transport of nutrients are discussed. The limitations of the available data are discussed in terms of identifying future research needs. The greatest need appears to be that of relating the limited data on small plots to larger watersheds, and edge-of-field losses to receiving waters.
A technique for sequential measurements of DC neuromagnetic fields

Magnetoencephalography (MEG) has the capability of detecting DC neuromagnetic fields which might arise from migraine, stroke, head trauma, etc. However, such fields are not readily measured in serial fashion for technical reasons, including arbitrary neuromagnetometer baselines, residual DC fields which vary from place to place inside conventional magnetically shielded rooms, and especially the high sensitivity of such measurements to small changes in distance between the probe and head. A technique is described to carry out such measurements by raising and lowering the subject under the probe and calibrating the DC shift against the amplitude of spontaneous activity.
SU-D-217BCD-03: Impact of Jaw Width on the Megavoltage Computed Tomography Image Quality and Imaging Dose with Helical Tomotherapy.

Purpose: On‐treatment megavoltage computed tomography on Helical Tomotherapy (Accuray Inc., Sunnyvale, CA) is critical for image guided radiotherapy. A strategy was developed to assess the impact of various jaw widths on image quality and imagingdose with Tomotherapy. Methods: A cheese phantom (Gammex RMI, Middleton, WI) made of water equivalent materials was employed in this study. Three sets of measurements were independently carried out. Firstly, in the imagingdose measurement, the phantom was placed on the couch and aligned with a stationary green laser and beam isocenter. The measurement point was 10 mm up from the cente of the phantom. Three slices on either side of the middle slice were selected. Secondly, two inserts with different rows of holes of various sizes were placed inside the phantom for imagecontrast and resolution investigation. Lastly, twelve density inserts were placed into the outer holes in the phantom for measurement of the image value to density table (IVDT). A comparison of imagingdose,image resolution and contrast, IVDT table between different jaw configurations was performed to evaluate the imaging system. Results:Imagingdose was 2.93 cGy with a jaw size of one mm as opposed to 1.62 cGy with a four mm jaw, both of which are below the vendor's requirement: 3 cGy. However, image quality is improved significantly with the smaller jaw. Four lines of holes can be readily identified on images using smaller jaw while only three lines visible with the larger jaw. Imagecontrast is similarly enhanced when reducing the jaw size. On average CT numbers are 6% higher with the smaller jaw than those obtained with the larger one. Conclusions: Significant improvement in image quality is achieved with the smaller jaw field in Tomotherapy while the imagingdose is kept at a clinically acceptable level.
Delays in the treatment of patients with aneurysmal subarachnoid hemorrhage: Experience at a county hospital

Abstract Background: Aneurysmal subarachnoid hemorrhage can have devastating consequences, but the early identification of patients with this condition can lead to early intervention to reduce the risks of rebleeding, vasospasm, and increased intracranial pressure. This study examines the characteristics of those patients who had a delay in presentation or transfer to a facility equipped to treat them. Methods: Cases of angiographically documented subarachnoid hemorrhage treated at the Los Angeles County General Hospital were retrospectively reviewed. An interval of 3 or more days between the onset of hemorrhage symptoms and admission to our hospital was defined as delayed. Results: Case records of the most recent 285 patients with 380 aneurysms treated at the Los Angeles County General Hospital were reviewed. One hundred twenty-two patients (42.8%) experienced a delay in admission. Records were available for 86 patients (70.5%). Delays in presentation did not differ by ethnicity. Delays were classified as patient-related (26.7%), delay to obtain an angiogram (19.8%), transportation-related (17.4%), initial misdiagnosis (17.4%), and radiographic misinterpretation (9.3%). Twenty-one patients went to an urgent care or outpatient clinic for treatment, of whom 19 were sent home. Twelve patients made 3 or more visits to a physician before being diagnosed. Eighteen patients suffered a rerupture before admission to our hospital. Nine of these were caused by patient delay, with a rerupture prompting an emergency visit, and 4 reruptures were the result of a radiographic misdiagnosis. Conclusions: Delays in the diagnosis and treatment of aneurysmal subarachnoid hemorrhage are frequent. Increased public awareness of the signs of a "Brain Attack," as well as improved physician education about subarachnoid hemorrhage should reduce delays in consultation and referral.