cssi/SciSciGPT-SciSciNet huggingface dataset:
Pharmacological maintenance of protein homeostasis could postpone age-related disease.

Summary Over the last 10 years, various screens of small molecules have been conducted to find long sought interventions in aging. Most of these studies were performed in invertebrates but the demonstration of pharmacological lifespan extension in the mouse has created considerable excitement. Since aging is a common risk factor for several chronic diseases, there is a reasonable expectation that some compounds capable of extending lifespan will be useful for preventing a range of age-related diseases. One of the potential targets is protein aggregation which is associated with several age-related diseases. Genetic studies have long indicated that protein homeostasis is a critical component of longevity but recently a series of chemicals have been identified in the nematode Caenorhabditis elegans that lead to the maintenance of the homeostatic network and extend lifespan. Herein we review these interventions in C. elegans and consider the potential of improving health by enhancing protein homeostasis.
Role of alcohol dehydrogenase in the swift increase in alcohol metabolism (SIAM). Studies with deer mice deficient in alcohol dehydrogenase.

Previous studies have shown that rates of ethanol metabolism increase markedly 2-4 hr after the administration of ethanol in rats and in four inbred strains of mice. This phenomenon, called the swift increase in alcohol metabolism (SIAM), also exists in humans. To determine whether alcohol dehydrogenase (ADH) is necessary for the SIAM response, we compared ethanol metabolism in two strains of the deer mouse, Peromyscus maniculatus. One strain lacks alcohol dehydrogenase (ADH-negative), whereas the other strain has normal ADH levels (ADH-positive). Rates of ethanol elimination were determined after a single intraperitoneal injection of ethanol at different doses (0.5 to 3.0 g/kg) and also after both strains were exposed to various levels of ethanol vapor for 4 hr. The ADH-positive strain exhibited up to a 72% increase in the rate of ethanol elimination after exposure to ethanol vapor compared to the ethanol-injected controls. In contrast, treatment with ethanol vapor did not alter rates of ethanol elimination in the ADH-negative strain. These data demonstrate clearly that ADH is required for SIAM in the deer mouse. In addition, in both the ADH-positive and the ADH-negative strain, rates of ethanol elimination increased in both the ethanol-injected and vapor-treated groups 2- to 3-fold as the dose of ethanol was increased from 100 to 500 mg/100 ml. Thus, it is concluded that this "concentration effect" of ethanol on rates of ethanol metabolism does not involve ADH in the . deer mouse.
Pooling of Urine Samples for Screening for Neisseria gonorrhoeae by Ligase Chain Reaction: Accuracy and Application

The accuracy of detection of genital Neisseria gonorrhoeae infection in pooled urine samples by ligase chain reaction (LCR) was examined in three populations. Firstly, urine specimens from 300 female military recruits (FMR) were tested by LCR individually and in pools of four and six. Secondly, 300 urine specimens from middle-school students (MSS) were tested individually by LCR, and then the processed specimens were stored frozen for subsequent testing in pools of 4 and 10. Thirdly, 600 frozen urine specimens from high-school students (HSS) were tested by using the LCR pooling algorithm, i.e., testing processed specimens in pools of four in one test unit dose, and retesting individual specimens from positive pools. Finally, the pooling algorithm results were compared to culture results for a subset of 344 students from the original 600 HSS from whom cervical or urethral samples were taken at the discretion of the school nurse practitioners. Compared to individual testing of specimens by LCR in the FMR population, the pooling-by-four algorithm was 100% sensitive (5 of 5) and 100% pool specific (70 of 70), and the pool-by-six algorithm was 100% sensitive (5 of 5) and 100% pool specific (45 of 45). In the MSS population, the pool-by-4 algorithm was 95.8% sensitive (23 of 24) and 100% (52 of 52) pool specific, and the pool-by-10 algorithm was 95.8% sensitive (23 of 24) and 100% (17 of 17) pool specific. In the subset of 344 HSS from whom endocervical or urethral specimens were collected for culture, 31 were positive by LCR in urine and 26 were positive by culture. After results discrepant between culture and LCR were adjudicated by a confirmatory LCR test, the pooling algorithm was 93.8% (30 of 32) sensitive and 99.7% (311 of 312) specific. Culture from these 344 HSS was 81.3% (26 of 32) sensitive. The pooling algorithm reduced the cost of the N. gonorrhoeae LCR assay by 60% compared to individual testing of the HSS specimens and was both sensitive and specific.
Equilibrium distribution of skeletal actin–tropomyosin–troponin states, determined by pyrene–tropomyosin fluorescence

Actin–tropomyosin–troponin has three structural states, but the functional properties of regulation can be explained with models having two functional states. As a step towards assigning functional properties to all the structural states, we examined fluorescent probes that monitor changes in troponin and tropomyosin. Tropomyosin labeled with pyrene–iodoacetamide is thought to reflect the transition to the most active state, whereas N-((2-iodoacetoxy)ethyl)-N-methyl)-amino-7-nitrobenz-2-oxa-1,3-diazole-labeled troponin I is thought to monitor the transition to any state other than the inactive state. The fraction of actin in an active state determined from pyrene excimer fluoresecence agreed with that calculated from light-scattering measurements of myosin subfragment 1 (S1)–ADP to regulated actin in both the presence and absence of Ca2+ over a range of ionic strength conditions. The only exceptions were conditions where the binding of S1–ADP to actin was too strong to measure accurately. Pyrene–tropomyosin excimer fluorescence was Ca2+ dependent and so reflected the change in population caused by both Ca2+ binding and S1–ADP binding. Pyrene labeling of tropomyosin did not cause a large perturbation of the transition among states of regulated actin. Using pyrene–tropomyosin fluorescence we were able to extend the ionic strength dependence of the parameters describing the co-operativity of binding of S1–ADP to actin as low as 0.1 m. The probes on tropomyosin and troponin I had different responses to Ca2+ and S1–ADP binding. These different sensitivities can be explained by an intermediate between the inactive and active states of regulated actin.
The Role of Class I Haplotype in the Development of Immune Mediated Brain Atrophy in a Murine MS Model (P1.169)

OBJECTIVE: To determine the effects of class I haplotype on brain atrophy development in the TMEV model of MS using transgenic mice. BACKGROUND: Brain atrophy is detectable from the earliest stages of MS, becoming especially prominent in progressive disease. In TMEV infected SJL/J mice we previously demonstrated brain atrophy and its strong association with disability. Similarly to SJL.J mice, FVB/NJ mice are susceptible to demyelination following TMEV infection, but they spontaneously remyelinate and don’t develop disability. We compared FVB/NJ mice with transgenic FVB mice of H2D(b) haplotype, where chronic demyelination is not expected due to efficient viral clearance. DESIGN/METHODS: 14 TMEV infected FVB/D(b) and 7 FVB/NJ mice were followed with monthly 125 micron isometric 7 Tesla MRI for 4 months. Brain atrophy was determined using established methods. Disability was assessed using monthly rotarod assay. Viral load was determined using RT-PCR. Statistical analysis was performed in SigmaPlot using t-tests. RESULTS: Mice with H2D(q) haplotype did not develop brain atrophy (p=0.48) despite chronic demyelination; whereas significant and persistent atrophy was demonstrated within a month in H2D(b) mice (p=0.00047). Rotarod detectable disability did not develop in either strain. Viral load persisted in FVB/NJ but not inH2D(q) mice. CONCLUSIONS: H2D(b) mice clear the virus mainly by CD8 T-cell mediated cytotoxicity directed at neurons, resulting in neuronal loss, leading to brain atrophy development. Altered neuronal maturation in the context of different class I haplotypes may also contribute to this process. Despite significant atrophy, disability doesnt develop in this strain. Although FVB/NJ mice do develop chronic demyelination, we neither observed significant atrophy nor rotarod detectable disability, consistent with the strain9s known characteristic of spontaneous remyelination. In the TMEV model, the development of atrophy is linked with neuronal loss in the brain, dependent on class I haplotype, which determines the efficiency of viral clearance. Brain atrophy only correlates with disability when persistent chronic demyelination also develops. Study Supported by: NIH NINDS and Mayo Clinic Intramural Funds Disclosure: Dr. Pirko has received personal compensation in an editorial capacity for Nanomedicine: Nanotechnology, Biology and Medicine. Dr. Pirko has received research support from Novartis Pharmaceuticals. Dr. Gamez has nothing to disclose. Dr. Atanga has nothing to disclose. Dr. LaFrance has nothing to disclose. Dr. Johnson has nothing to disclose.
Cotton Island: Students' Learning Motivation Using a Virtual World

As technology advances, it is important for teachers to seamlessly integrate technology into their innovative teaching techniques. Using virtual worlds is one alternative to traditional teaching methods that can provide rich learning experiences. The purpose of this article is twofold: (a) to present Cotton Island, an avatar-based 3-D virtual learning environment in Second Life and (b) to evaluate students’ learning motivation in using Cotton Island as a learning tool. Cotton Island was designed with unique navigational features to provide access to rich resources and educational activities that improve students’ knowledge of cotton. Based on the ARCS (attention, relevance, confidence, and satisfaction) model, this study assesses students’ learning motivation when using Cotton Island as a learning tool, and whether students had a positive learning outcome consistent with the instructors’ goal of knowledge improvement. The results show that students had a positive experience in terms of learning motivation and knowledge improvement.
Short communication: Postpasteurization hold temperatures of 4 or 6°C, but not raw milk holding of 24 or 72 hours, affect bacterial outgrowth in pasteurized fluid milk

As fluid milk processors continue to reduce microbial spoilage in fluid milk through improved control of postpasteurization contamination and psychrotolerant sporeformer outgrowth, it is necessary to identify strategies to further improve the quality and extend the shelf life of fluid milk products that are high-temperature, short-time pasteurized. Solutions that optimize product quality, and are economically feasible, are of particular interest to the dairy industry. To this end, this study examined the effects of raw milk holding time and temperature of pasteurized milk storage over shelf life on bacterial growth. In 3 independent replicates, raw milk was stored for 24 and 72 h before pasteurization at 76°C for 25s and then incubated at 3 different storage conditions: (1) 4°C for 21d; (2) 4°C for the first 48 h, then 6°C for the duration of the 21-d shelf life; or (3) 6°C for 21d. Total bacteria counts were assessed initially and on d 7, 14, and 21. No substantial difference in bacterial growth over shelf life was observed between samples processed from raw milk held for 24 versus 72 h. A significantly lower bacterial load was seen at d 21 after pasteurization in samples held at 4°C, versus 4°C for the first 48 h followed by 6°C for the duration of the 21-d shelf life and samples held at 6°C for 21d. This work demonstrates the importance of maintaining control of the fluid milk cold chain throughout postpasteurization, transportation, and retail storage on fluid milk microbial quality.
Influence of sample matrix components on the selection of calibration strategies in electrothermal vaporization inductively coupled plasma mass spectrometry

Abstract Quantification of both digested and slurry samples were studied using ultrasonic slurry electrothermal vaporization inductively coupled plasma mass spectrometry (USS-ETV-ICP-MS). The results of external calibration using aqueous standards, method of additions, and In as an internal standard were compared. The elements studied include: Mn, Ni and Cu and the materials analyzed include: NIST SRM 1548 total diet and SRM 1549 milk powder. Palladium was used as a physical carrier and oxygen ashing was used to remove the organic part of the slurry matrix. Different degrees of matrix suppression effects were observed when different skimmer cones were employed. Aging of the skimmer cone and consequent loss of its original circular symmetry and decrease in orifice size resulted in differences in sampling of the ion beam and changes in the degree of matrix effects were observed as the skimmer cone was rotated. The presence of matrix suppression effects is evidenced by strong suppressions in the Ar 2 , C and analyte signals. When matrix suppression effects were present, the method of external calibration provided low recoveries (average accuracy 73 ± 12%), therefore it was necessary to use the method of additions to compensate for these problems, providing an average accuracy of 108 ± 13%. When matrix effects were absent, the external calibration method resulted in an average accuracy of 101 ± 16%.
Coiling Direction of Globigerina pachyderma as a Climatic Index

An interdependence between the geographical distribution of dextral and sinistral populations of the planktonic foraminifer, Globigerina pachyderma, and sea surface-temperatures is demonstrated. It is inferred that changes in dominant coiling direction at lower levels in sediment cores from the North Atlantic record southward shifts of isotherms during the last ice age.
Advancing Engineering Education in P-12 Classrooms

Engineering as a profession faces the challenge of making the use of technology ubiquitous and transparent in society while at the same time raising young learners' interest and understanding of how technology works. Educational efforts in science, technology, engineering, and mathematics (i.e., STEM disciplines) continue to grow in pre-kindergarten through 12th grade (P-12) as part of addressing this challenge. This article explores how engineering education can support acquisition of a wide range of knowledge and skills associated with comprehending and using STEM knowledge to accomplish real world problem solving through design, troubleshooting, and analysis activities. We present several promising instructional models for teaching engineering in P-12 classrooms as examples of how engineering can be integrated into the curriculum. While the introduction of engineering education into P-12 classrooms presents a number of opportunities for STEM learning, it also raises issues regarding teacher knowledge and professional development, and institutional challenges such as curricular standards and high-stakes assessments. These issues are considered briefly with respect to providing direction for future research and development on engineering in P-12.
Advances in energy harvesting using low profile piezoelectric transducers

The vast reduction in the size and power consumption of sensors and CMOS circuitry has led to a focused research effort on the on-board power sources which can replace the batteries. The concern with batteries has been that they must always be charged before use. Similarly, the sensors and data acquisition components in distributed networks require centralized energy sources for their operation. In some applications such as sensors for structural health monitoring in remote locations, geographically inaccessible temperature or humidity sensors, the battery charging or replacement operations can be tedious and expensive. Logically, the emphasis in such cases has been on developing the on-site generators that can transform any available form of energy at the location into electrical energy. Piezoelectric energy harvesting has emerged as one of the prime methods for transforming mechanical energy into electric energy. This review article provides a comprehensive coverage of the recent developments in the area of piezoelectric energy harvesting using low profile transducers and provides the results for various energy harvesting prototype devices. A brief discussion is also presented on the selection of the piezoelectric materials for on and off resonance applications. Analytical models reported in literature to describe the efficiency and power magnitude of the energy harvesting process are analyzed.
Isolation of herpes simplex virus DNA from the "hirt supernatant".

Abstract Herpes simplex virus DNA was isolated from infected cells by its preferential release into the “Hirt supernatant” and its subsequent sedimentation in neutral glycerol gradients. The DNA isolated by this procedure was free from contamination with cellular DNA and was identical in its kinetic complexity to the DNA isolated from intact virions.
Evidence for a (Triosephosphate Isomerase-like) "Catalytic Loop" near the Active Site of Glyoxalase I

Abstract The conformational mobility of glyoxalase I (Glx I) during catalysis has been probed using stable analogs of the enediol intermediate that forms along the reaction pathway: GSC(O)N(OH)R, where GS = glutathionyl and R = CH3 (1), C6H5 (2), C6H4Cl (3), or C6H4Br (4). For human erythrocyte Glx I, catalysis is unlikely to be coupled to major changes in protein secondary structure, as the circular dichroism spectrum of the enzyme (190-260 nm) is insensitive to saturating concentrations of either enediol analog or S-D-lactoylglutathione, the product of the Glx I reaction. However, a small conformational change is indicated by the fact that binding of enediol analog to the active site decreases intrinsic protein fluorescence by 11%, and protects the enzyme from proteolytic cleavage by Pronase E at the C-side of Ala-92 and Leu-93. In contrast, binding of S-D-lactoylglutathione does not affect protein fluorescence, and increases the rate of proteolytic cleavage by 1.5-fold. These observations are consistent with a model of catalysis in which a flexible peptide loop folds over and stabilizes the enediol intermediate bound to the active site. Indeed, a highly conserved sequence of amino acid residues is found near the proteolytic cleavage sites, for human Glx I(100-111) and Pseudomonas putida Glx I(93-105), that shows significant sequence homology to the “catalytic loop” of chicken muscle triosephosphate isomerase (TIM)(165-176). The active site base (Glu-165) of TIM, which catalyzes the proton transfer reaction during isomerization, corresponds in position to Glu-93 of P. putida Glx I. Consistent with a functional role for Glu-93, a mutant enzyme in which Glu-93 is replaced by Asp shows no detectable catalytic activity.
A TAX REFORM STRATEGY TO DEAL WITH THE UNINSURED

The high level of ininsurance in the United States is due in large measure to the tax treatment of health care, which is based on the tax exclusion for company-provided plans. Correcting the perverse incentives for providers and patients resulting from this tax treatment is the crucial step to creating a national health care system that is affordable and efficient. The Heritage Foundation proposal calls for the elimination of the current tax exclusion and its replacement with a system of refundable tax credits for the purchase of health insurance and medical services.
Opportunities for Oncology in the Patient Protection and Affordable Care Act

The Patient Protection and Affordable Care Act (ACA) contains within it three significant legislative constructs: to enhance access to health care, improve quality, and decrease cost. Also known as...
1H and 15N resonance assignments and secondary structure of the human thioredoxin C62A, C69A, C73A mutant.

The complete assignment of 1H and 15N backbone resonances and near-complete 1H side-chain resonance assignments have been obtained for the reduced form of a mutant of human thioredoxin (105 residues) in which the three non-active site cysteines have been substituted by alanines: C62A, C69A, C73A. The assignments were made primarily on the basis of three-dimensional 15N-separated nuclear Overhauser and Hartmann-Hahn spectroscopy, in conjunction with two-dimensional homonuclear and heteronuclear correlation experiments. Based on comparisons of short-range and interstrand nuclear Overhauser effects, patterns of amide exchange, and chemical-shift differences, the structure appears essentially unchanged from that of the previously determined solution structure of the native protein [Forman-Kay, J.D. et al. (1991) Biochemistry, 30, 2685-2698]. An assay for thioredoxin shows that the C62A, C69A, C73A mutant retains activity. The assignment of the spectrum for this mutant of human thioredoxin constitutes the basis for future studies aimed at comparing the details of the active-site conformation in the reduced and oxidized forms of the protein.
Stabilization for intensity-based sensors using two-wavelength ratio technique

Stabilization for intensity-based sensors using two-wavelength ratio techniqueGeorge Z. Wang, Anbo Wang, Russell G. May, Adam Barnes,Kent A. Murphy, and Richard 0. ClausFiber & Electro-Optics Research CenterBradley Department of Electrical Engineering, Virginia Tech106 Plantation Rd., Blacksburg, Virginia 24061-0356ABSTRACTIntensity-based fiber optic sensors are referred to those sensors whose outputs aremodulated by intensity levels and not optical phase variations. The attractive features ofintensity-based sensors over interferometric sensors include simple in structure, absolutemeasurement and long-term stability in performance. One important issue for intensity-based fiber sensors is stabilization schemes used to compensate for unwanted disturbancesin sensing systems. Two-wavelength ratio (TWR) method is one of the most commonlyused compensation technique. In this paper, we study the TWR method in great details bydiscussing four novel intensity-based sensors developed in our research group. Thesefiber sensors are : (1) High temperature sensor based on the total internal reflection (TIR)with temperature measurement up to 1000 °C; (2) Temperature sensor and distributedsensing system using dielectric filters, achieving temperature measurement of more than100 °C and a resolution of 0.5 °C; (3) Displacement sensor using diffraction gratingreflector with a dynamic range of 150 tm and 2 .tm resolution; (4) Displacement sensorusing GRIN lens having a displacement range up to 20 .tm with sub-rim resolution. Issuesrelated to the signal transmission in sensing systems are also addressed.1. INTRODUCTIONIntensity-based fiber optic sensors have been used to measure various parameters
Glycosidase activity of bovine liver plasma membranes.

1. 1. Plasma membranes were isolated on a large scale from bovine liver by a modified method of Neville1. They were characterized with respect to contamination by endoplasmic reticulum, lysosomes, and mitochondria. 2. 2. The membranes were found to contain glycosidases capable of hydrolyzing uridine diphosphogalactose (UDP-Gal) and uridine diphosphoglucose as well as o-nitrophenyl α- or β-galactosides. 3. 3. The hydrolysis of UDP-Gal using a 14C-labeled substrate in the galactose moiety allowed a rapid estimation of the amount of plasma membrane contaminating microsomal fractions. Smooth microsomes were contaminated about 14% with plasma membranes. This value agreed with estimates based on the content of Mg2+-stimulated ATPase and of 5′-nucleotidase. Rough microsomes contained about 5% plasma membranes using this criterion. Purified nuclei and mitochondria from bovine liver showed negligible amounts of this activity. 4. 4. The optimum pH of the enzyme was 7.2 using cacodylate buffer. Mg2+ stimulated the activity slightly whereas Mn2+ was inhibitory. The Km for UDP-Gal was 0.33 mM.
Long-Term Follow-up of Lobular Neoplasia (Atypical Lobular Hyperplasia/Lobular Carcinoma In Situ) Diagnosed on Core Needle Biopsy

Lobular neoplasia (LN) includes atypical lobular hyperplasia (ALH) and lobular carcinoma in situ (LCIS). LN often is an incidental finding on breast core needle biopsy (CNBx) and management remains controversial. Our objective was to define the incidence of malignancy in women diagnosed with pure LN on CNBx, and identify a subset of patients that may be observed. Patients diagnosed with LN on CNB between January 1993 and December 2010 were identified. Patients with an associated high-risk lesion or ipsilateral malignancy at time of diagnosis were excluded. All cases were reviewed by dedicated breast pathologists and breast imagers for pathologic classification and radiologic concordance, respectively. The study cohort was comprised of 184 (1.3 %) cases of pure LN (147 ALH, 37 LCIS) from 180 patients. Pathologic–radiologic concordance was achieved in 171 (93 %) cases. Excision was performed in 101 (55 %) cases and 83 (45 %) were observed. Mean follow-up was 50.3 (range, 6–212) months. Of cases excised, 1 of 81 (1.2 %) ALH and 1 of 20 (5 %) LCIS cases were upstaged to ductal carcinoma in situ (DCIS) and invasive lobular carcinoma (ILC), respectively. Only 1 of 101 (1 %) concordant lesions was upstaged on excision. Of the cases observed, 4 of 65 (6.2 %) developed ipsilateral cancer during follow-up: 1 of 51 (2 %) case of ALH and 3 of 14 (21.4 %) cases with LCIS (2 ILC, 2 DCIS). During follow-up, 2.9 % (4/138) patients with excised or observed LN developed a contralateral cancer. These data support that not all patients with LN diagnosed on CNB require surgical excision. Patients with pure ALH, demonstrating radiologic–pathologic concordance, may be safely observed.
Adirondack Park Incidents: A Retrospective Review of Search and Rescue Reports From 2008 and 2009

Background The Adirondack Park is a 6 million acre recreational area in northeastern New York used for activities such as hiking, camping, canoeing, hunting, fishing, snowmobiling, skiing, and rock climbing. Given the large number of people who use the Adirondacks for recreation, there exists the potential for many accidents, injuries, and illnesses to occur in areas ranging from state-operated campgrounds to remote backcountry. Objective The aim of this study was to gain insight into the demographics of search and rescue (SAR) operations in the Adirondack Park. Methods This study is a retrospective review of the Adirondack Park Forest Ranger SAR reports from January 1, 2008, through December 31, 2009. Epidemiologic data were gathered from the NY State Department of Environmental Conservation for each report, including victim demographics, incident, reason for injury, medical care needed, preparation of victim, and prior medical conditions. Results In all, 239 SAR missions were carried out involving at least 349 victims. Of all cases, 28% (66) involved an injured victim, and 9% (21) involved illness; 56% (10) of the victims had a known prior illness or medical condition; and 21% (27) of cases were due to victims exceeding their abilities. Of the search missions, 54% of victims (93) had little experience with the activity, and 9% (15) had no experience. Only 43% (62) of victims had any form of orientation equipment. Conclusions This study portrays the initial demographics of SAR efforts in Adirondack Park. It will aid in educating people on preparing for wilderness activities, as well as tailoring SAR resources to the demographics of injury and illness within the park.
Single-passage Euler analysis of oscillating cascade aerodynamics for arbitrary interblade phase

The unsteady flowfield through a harmonically oscillating cascade of airfoils is investigated using a timemarching Euler code implemented on a deforming C-grid. Various methods of calculating the boundary conditions are considered, with special attention paid to the unsteady periodic boundary conditions and reducing computer resource requirements. The Euler code is then used to predict the unsteady aerodynamics for both translational and torsional cascade oscillations for several cascade flow geometries. A flat plate cascade is used to verify the flow solver with linear theory predictions. A typical compressor rotor configuration is used to introduce nonlinear effects. The effect of a strong normal shock with varied amplitudes of oscillation demonstrates the nonlinear behavior of the periodic boundary conditions and helps to define the limiting conditions for linearized analyses.
A computer‐based free body diagram assistant

We developed an online Free Body Diagram (FBD) Assistant that allows students to construct 2-D FBDs and to receive constructive feedback for a wide range of practice problems. The system's architecture allows for interoperability between learning management systems and interactive student simulations designed to improve both learning and assessment. The system gathers useful information about students' decision processes as they construct FBDs. This information can be used with a diagnostic module we have developed to reliably, and dynamically, construct appropriate feedback that is specific to the diagram submitted by the student. Students use this asynchronous system to gain practice in constructing FBDs at their own pace, and their records can be analyzed to indicate progress over time. © 2006 Wiley Periodicals, Inc. Comput Appl Eng Educ 14: 281–290, 2006; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20088
Disc space-targeted angled axial MR images of the lumbar spine: a potential source of diagnostic error.

Objective To compare the sensitivities of contiguous axial (CA) images and disc space-targeted angled axial (DSTAA) images of the lumbar spine for: (1) the detection of spondylolysis defects, and (2) the identification of disc material which has migrated away from the parent disc.
A phase I/II trial of intensity-modulated radiation (IMRT) dose escalation with concurrent fixed- dose rate gemcitabine (FDR-G) in patients with unresectable pancreatic cancer

Purpose Local failure in unresectable pancreatic cancer may contribute to death. We hypothesized that intensification of local therapy would improve local control and survival. The objectives were to determine the maximum tolerated radiation dose delivered by intensity modulated radiation with fixed-dose rate gemcitabine (FDR-G), freedom from local progression (FFLP), and overall survival (OS). Methods and Materials Eligibility included pathologic confirmation of adenocarcinoma, radiographically unresectable, performance status of 0-2, absolute neutrophil count of ≥1500/mm 3 , platelets ≥100,000/mm 3 , creatinine 2 /100 min intravenously) was given on days −22 and −15, 1, 8, 22, and 29. Intensity modulated radiation started on day 1. Dose levels were escalated from 50-60 Gy in 25 fractions. Dose-limiting toxicity was defined as gastrointestinal toxicity grade (G) ≥3, neutropenic fever, or deterioration in performance status to ≥3 between day 1 and 126. Dose level was assigned using TITE-CRM (Time-to-Event Continual Reassessment Method) with the target dose-limiting toxicity (DLT) rate set to 0.25. Results Fifty patients were accrued. DLTs were observed in 11 patients: G3/4 anorexia, nausea, vomiting, and/or dehydration (7); duodenal bleed (3); duodenal perforation (1). The recommended dose is 55 Gy, producing a probability of DLT of 0.24. The 2-year FFLP is 59% (95% confidence interval [CI]: 32-79). Median and 2-year overall survival are 14.8 months (95% CI: 12.6-22.2) and 30% (95% CI 17-45). Twelve patients underwent resection (10 R0, 2 R1) and survived a median of 32 months. Conclusions High-dose radiation therapy with concurrent FDR-G can be delivered safely. The encouraging efficacy data suggest that outcome may be improved in unresectable patients through intensification of local therapy.
Eigenvalues and the Smith normal form

Abstract We compare the Smith normal form (SNF) over the integers of an integral nonsingular matrix with its spectrum when its eigenvalues are integers. Our results include tight bounds on the size of the largest element of the SNF when the matrix is diagonalizable with nonzero integer eigenvalues, with no assumptions on the diagonalizing matrices.
Monte Carlo calculations for an O(3)Z2 lattice spin model in 2 dimensions

Abstract A modified 2-dimensional O(3) spin model in which the global properties admit Z 2 vortices is considered. We have performed a detailed Monte Carlo calculation studying the energy, specific heat, correlation length, susceptibility and vortex density. No evidence for any phase transition is found. The crossover to the asymptotic freedom regime is found to occur at too low a temperature to be accessible to simple Monte Carlo techniques.
A review of directed graphs as applied to computors

The complexity of digital computers and their large scale use have led some researchers to investigate tools not commonly used. In recent years, applications of graph theory to computers as well as other fields of study have given fruitful results and have attracted more and more scientists. The attempt here will be to review previous accomplishments on a fundamental level and to stimulate the reader to investigate an area where valuable work is being performed.
Anomalous electroweak couplings of the tau and tau neutrino

Abstract This paper reviews the status of measurements of anomalous electric and magnetic moment type couplings of the tau and its neutrino. An outlook and summary of points to focus on in the future is also given.
Input-Gain Control Produces Feature-Specific Surround Suppression

In primary visual cortex (V1), neuronal responses are sensitive to context. For example, responses to stimuli presented within the receptive field (RF) center are often suppressed by stimuli within the RF surround, and this suppression tends to be strongest when the center and surround stimuli match. We sought to identify the mechanism that gives rise to these properties of surround modulation. To do so, we exploited the stability of implanted multielectrode arrays to record from neurons in V1 of alert monkeys with multiple stimulus sets that more exhaustively probed center-surround interactions. We first replicated previous results concerning center-surround similarity using gratings representing all combinations of center and surround orientation. With this stimulus set, the surround simply scaled population responses to the center, such that the overall population tuning curve had the same shape and peak response. However, when the center contained two superimposed gratings (i.e., a visual “plaid”), one component of which always matched the surround orientation, suppression selectively affected the portion of the response driven by the matching center component, thereby producing shifts in the peak of the population orientation tuning curve. In effect, the surround caused neurons to respond predominantly to the component grating of the center plaid that was unmatched to the surround grating, as if by reducing the effective strength of whichever stimulus attributes were matched to the surround. These results provide key physiological support for theoretical models that propose feature-specific, input-gain control as the mechanism underlying surround suppression.
Parameter sets for bounded-error data

Abstract A simple approach to the development of user-friendly software for the bounded-error approach to parameter estimation is offered. It enables the computer determination of the boundaries of the set of all parameters satisfying the bounded-error constraints, whether the problem is linear or nonlinear, and whether the parameter set is connected or disconnected.
Detection of zonal renal ischemia with contrast-enhanced MR imaging with a macromolecular blood pool contrast agent.

The potential of magnetic resonance (MR) imaging enhanced with albumin-(gadolinium diethylenetri-aminepentaacetic acid [DTPA])35, a macromolecular blood pool marker, for detection of focal changes in renal perfusion was studied in a myoglobinuric acute renal failure (ARF) model in the rat. T1-weighted spin-echo postcontrast images of injured kidneys at 3 hours after glycerol injection showed three distinct zones: a strongly enhanced outer cortex, a low-intensity inner cortex, and a strongly enhanced medulla. The distinct band of low intensity in the inner cortex indicated zonal decreased blood volume, corresponding to published microsphere data showing zonal low perfusion in the inner cortex. Contrast differences between parenchymal zones were significant for at least 30 minutes. No focal ischemic changes could be delineated on nonenhanced images. Enhanced and nonenhanced images of injured kidneys obtained at 24 hours after glycerol injection revealed no zonal differentiation. Contrast-enhanced MR imaging data in this ARF model correlated well with pathologic data and microsphere perfusion results. Contrast-enhanced characterization of the ischemic phase of renal injury with MR imaging may improve specificity for the diagnosis of ARF and may serve as a marker for therapeutic intervention.
Patterns of Variation in the Influence of Natal Experience on Habitat Choice

The experience of animals in their natal or larval habitats has long been considered a potential source of variation in the habitat choices made later during dispersal. This idea has been of particular interest to evolutionary biologists because of the role such variation plays in the formation of host races and species. However, experiments that have tested for the effect of natal experience on habitat choice have produced widely variable results, leading to disagreement about the ecological importance of these effects. Here, I review the results of experiments within a broad range of animal taxa to assess the potential sources of variation in observed effects of natal experience on habitat choice. I provide a comprehensive summary of previous studies and demonstrate that when natal experience influences habitat choice, it nearly always increases the acceptance of the natal habitat type. Furthermore, I discuss mechanisms that allow natal experience to affect later habitat choice and describe how these mechanisms are influenced by various experimental design elements, such as the life stage at which early experience is provided to subjects. I conclude by reviewing the adaptive hypotheses for why animals might or might not respond to natal experience, and also how these hypotheses might explain interspecific differences in the importance of natal experience during habitat selection decisions. By understanding in what species, and in which contexts, experience influences habitat selection, we will be able to predict the ecological and evolutionary consequences of these effects more accurately.
NEW ANAEROBIC METHODS

1. Anaerobic methods have been devised which depend upon the catalytic action of platinized asbestos upon hydrogen and oxygen. 2. The methods may be utilized for the growth of anaerobes in test-tubes, upon Blake bottles, in flasks, and in a large container. 3. Because oxygen is so completely removed, the methods are of great value in the successful cultivation of absolute anaerobes.
Effects of a Random versus Pattern Instructional Set in a Contingent Partial Reinforcement Situation

The characteristic response curves of Ss operating under partial reinforcement are well-known. In a two-choice situation, for instance, they start off responding equally to both choices and then increase the proportion of their responses to the most profitable choice. Ordinarily, the final level of response is less than 100% preference for the alternative associated with the most frequent reward. Possibly, Ss try to "match" the occurrence of the reinforcement, assuming incorrectly that its schedule is patterned. Hence, they will vary their choices between the two alternatives in the expectation of the occurrence of reward at both of them. Flood (6) has hypothesized that the pure type of behavior (100% responding to the most profitable side) will be found in Ss who are convinced of randomness while the mixed type of behavior (trying to anticipate reward on the least profitable side as well) would be obtained when Ss believed there was a patterned arrangement in the occurrence of reinforcement. To test Flood's hypothesis we have varied the instructional sets given to Ss. One group was told that the reinforcements were being manipulated according to a pattern and it was their task to ascertain what this pattern was to get as many rewarded responses as possible. A second group was told that the reinforcements were being manipulated in a completely random fashion, and it was their task to get as many rewarded responses as they could. Accordingly, one would expect the second group to respond more often to the most profitable side, if Ss believed the instructions given to them.
The role of acculturation in the emerging adulthood of aboriginal college students

Compared to traditional, non-Western cultures, emerging adulthood (18-25 years of age) may look considerably different in cultures that place emphasis on the group (i.e., collectivistic) over the individual (i.e., individualistic). However, within minority cultures, individual members vary on the extent to which they identify with their heritage culture. Thus, the purpose of this study was to explore the role that culture, particularly acculturation to Canadian aboriginal heritage culture, may play in emerging adulthood. Specifically, aboriginal emerging adults who scored above or below the mean of their peers on acculturation to their heritage (aboriginal) culture were compared to their majority European Canadian counterparts in several aspects of emerging adulthood including (a) perceived adult status, (b) perceived criteria for adulthood, (c) achieved criteria for adulthood, (d) personal beliefs about the future, and (e) risk behaviours. Results revealed the significance of examining acculturation in u...
Exotic S = 1 spin-liquid state with fermionic excitations on the triangular lattice

Motivated by recent experiments on the material Ba${}_{3}$NiSb${}_{2}$O${}_{9}$, we consider a spin-one quantum antiferromagnet on a triangular lattice with the Heisenberg bilinear and biquadratic exchange interactions and a single-ion anisotropy. Using a fermionic ``triplon'' representation for spins, we study the phase diagram within mean-field theory. In addition to a fully gapped spin-liquid ground state, we find a state where one gapless triplon mode with a Fermi surface coexists with $d+id$ topological pairing of the other triplons. Despite the existence of a Fermi surface, this ground state has fully gapped bulk spin excitations. Such a state has linear in-temperature specific heat and constant in-plane spin susceptibility, with an unusually high Wilson ratio.
Amolecular dynamics simulation of collisional excitation mechanisms in Al

A modified version of the SPUT2 molecular dynamics sputtering code was used to reinvestigate core excitation in Al atoms following bombardment with 1–5 keV Ar+ ions. For all bombarding energies, asymmetric collisions between the incoming ion and target atoms yielded smaller minimum distances-of-closest-approach between the collision partners for hard collisions than did symmetric collisions between pairs of target atoms. Simple critical distance-of-closest-approach models were used to estimate core excitation for both asymmetric and symmetric collisions. A single value of Rc (0.367 A) was used for asymmetric Ar-Al collisions, while two choices of Rc were used for symmetric Al-Al collisions (0.442 and 0.530 A). With the smaller Rc value for Al-Al collisions, we find that core excitation proceeds predominantly by asymmetric collisions at all bombarding energies above threshold. At 5 keV bombarding energy the percentage of sputtered, core-excited atoms originating from asymmetric collisions ranged from 89 to 95% depending on the incident direction of the projectile. With the larger Rc value, core excitation proceeds predominantly by asymmetric collisions at bombarding energies above approximately 3 keV; and at 5 keV asymmetric collisions accounted for ∼ 60 to ∼ 84% of sputtered, core-excited atoms. Lifetime corrections and corrections for Auger neutralization near the target surface had little effect on the ratio of asymmetric to symmetric collisions responsible for atomic-like Auger emission. These simulation results suggest that simultaneous multiple collisions are very important in the initial energy- and momentum-transfer stage which initiates the cascade.
OVERVIEW OF OTOLARYNGIC ALLERGY MANAGEMENT: An Eclectic and Cost-Effective Approach

Allergic rhinitis afflicts between 17% to 22% of Americans, and has been estimated to account for up to $4 billion in health care costs each year. When considering the associated disorders such as recurrent rhinosinusitis, otitis, bronchitis, and asthma, the costs may reach $10 billion annually. Even this fact may be underestimated as patients' symptoms may not be considered allergic in origin. This article deals with the timely subject of cost containment of allergic disorders within otolaryngology. There are currently no references that deal exclusively with the subject of cost-effectiveness of allergic disorders of the ear, nose, and throat. Physicians are actively engaged in the economics of medical practice, and managed care organizations openly discuss their needs to reduce expenditures, specifically in pharmaceutical and laboratory costs. It behooves us to examine the various methods of the investigation and treatment plans of ear, nose, and throat (ENT) allergy from an accounting point of view. We may be able to position ourselves in the overall scheme of rendering appropriate care to our patients. As otolaryngologists, we see and treat the entire upper airway, and a majority of our patients have allergic disorders that bring them to seek medical attention. These disorders include the complaints of rhinitis, rhinosinusitis, otitis, and laryngitis. Otolaryngologists stand in the front line of making appropriate decisions for effective management of upper respiratory allergic problems.
Purpose versus practice in the use of electronically monitored home confinement

This paper explores differences between the stated purpose and actual practice of electronically monitored home confinement as a prison-diversion strategy. Methods and data are triangulated to examine the difference between the stated purposes of electronic monitoring and its actual usage in two contexts: 1) the decision to imprison/probate; and 2) the actual use of electronically monitored home confinement. Sentencing information, along with data on employment, family, substance abuse, prior convictions, and type of offense, were collected on 391 felony offenders sentenced to probation in 1987–89 from three counties located in two large Metropolitan Statistical Areas in Texas. Information gathered from interviews with probation officials is also employed. This paper presents an analysis of this data and discusses its implications for future use and evaluation of electronically monitored home confinement.