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Sample records for modeling grade iv

  1. Characterization of the 9L gliosarcoma implanted in the Fischer rat: an orthotopic model for a grade IV brain tumor.

    Science.gov (United States)

    Bouchet, Audrey; Bidart, Marie; Miladi, Imen; Le Clec'h, Céline; Serduc, Raphaël; Coutton, Charles; Regnard, Pierrick; Khalil, Enam; Dufort, Sandrine; Lemasson, Benjamin; Laissue, Jean; Pelletier, Laurent; Le Duc, Géraldine

    2014-07-01

    Among rodent models for brain tumors, the 9L gliosarcoma is one of the most widely used. Our 9L-European Synchrotron Radiation Facility (ESRF) model was developed from cells acquired at the Brookhaven National Laboratory (NY, USA) in 1997 and implanted in the right caudate nucleus of syngeneic Fisher rats. It has been largely used by the user community of the ESRF during the last decade, for imaging, radiotherapy, and chemotherapy, including innovative treatments based on particular irradiation techniques and/or use of new drugs. This work presents a detailed study of its characteristics, assessed by magnetic resonance imaging (MRI), histology, immunohistochemistry, and cytogenetic analysis. The data used for this work were from rats sampled in six experiments carried out over a 3-year period in our lab (total number of rats = 142). The 9L-ESRF tumors were induced by a stereotactic inoculation of 10(4) 9L cells in the right caudate nucleus of the brain. The assessment of vascular parameters was performed by MRI (blood volume fraction and vascular size index) and by immunostaining of vessels (rat endothelial cell antigen-1 and type IV collagen). Immunohistochemistry and regular histology were used to describe features such as tumor cell infiltration, necrosis area, nuclear pleomorphism, cellularity, mitotic characteristics, leukocytic infiltration, proliferation, and inflammation. Moreover, for each of the six experiments, the survival of the animals was assessed and related to the tumor growth observed by MRI or histology. Additionally, the cytogenetic status of the 9L cells used at ESRF lab was investigated by comparative genomics hybridization analysis. Finally, the response of the 9L-ESRF tumor to radiotherapy was estimated by plotting the survival curves after irradiation. The median survival time of 9L-ESRF tumor-bearing rats was highly reproducible (19-20 days). The 9L-ESRF tumors presented a quasi-exponential growth, were highly vascularized with a high

  2. Nonoperative management for patients with grade IV blunt hepatic trauma

    Directory of Open Access Journals (Sweden)

    Zago Thiago

    2012-08-01

    Full Text Available Abstract Introduction The treatment of complex liver injuries remains a challenge. Nonoperative treatment for such injuries is increasingly being adopted as the initial management strategy. We reviewed our experience, at a University teaching hospital, in the nonoperative management of grade IV liver injuries with the intent to evaluate failure rates; need for angioembolization and blood transfusions; and in-hospital mortality and complications. Methods This is a retrospective analysis conducted at a single large trauma centre in Brazil. All consecutive, hemodynamically stable, blunt trauma patients with grade IV hepatic injury, between 1996 and 2011, were analyzed. Demographics and baseline characteristics were recorded. Failure of nonoperative management was defined by the need for surgical intervention. Need for angioembolization and transfusions, in-hospital death, and complications were also assessed Results Eighteen patients with grade IV hepatic injury treated nonoperatively during the study period were included. The nonoperative treatment failed in only one patient (5.5% who had refractory abdominal pain. However, no missed injuries and/or worsening of bleeding were observed during the operation. None of the patients died nor need angioembolization. No complications directly related to the liver were observed. Unrelated complications to the liver occurred in three patients (16.7%; one patient developed a tracheal stenosis (secondary to tracheal intubation; one had pleural effusion; and one developed an abscess in the pleural cavity. The hospital length of stay was on average 11.56 days. Conclusions In our experience, nonoperative management of grade IV liver injury for stable blunt trauma patients is associated with high success rates without significant complications.

  3. Grade III or Grade IV Hypertensive Retinopathy with Severely Elevated Blood Pressure

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    Amanda D Henderson

    2012-12-01

    Full Text Available Introduction: Hypertensive retinopathy describes a spectrum of retinal changes in patients with elevated blood pressure (BP. It is unknown why some patients are more likely to develop acute ocular end-organ damage than others with similar BP. We examined risk factors for grade III/IV hypertensive retinopathy among patients with hypertensive urgency in the emergency department (ED and compared healthcare utilization and mortality between patients with and without grade III/IV hypertensive retinopathy.Methods: A preplanned subanalysis of patients who presented to a university hospital ED with diastolic BP > 120 mmHg and who enrolled in the Fundus Photography versus Ophthalmoscopy Trial Outcomes in the ED study was performed. Bilateral nonmydriatic ocular fundus photographs, vital signs, and demographics were obtained at presentation. Past medical history, laboratory values, healthcare utilization, and mortality were ascertained from medical record review at least 8 months after initial ED visit.Results: Twenty-one patients with diastolic BP > 120 mmHg, 7 of whom (33% had grade III/IV hypertensive retinopathy, were included. Patients with retinopathy were significantly younger than those without (median 33 vs 50 years, P = 0.02. Mean arterial pressure (165 vs 163 mmHg was essentially equal in the 2 groups. Patients with retinopathy had substantially increased but nonsignificant rates of ED revisit (57% vs 29%, P = 0.35 and hospital admission after ED discharge (43% vs 14%, P = 0.28. One of the patients with retinopathy died, but none without.Conclusion: Younger patients may be at higher risk for grade III/IV hypertensive retinopathy among patients with hypertensive urgency. Chronic compensatory mechanisms may have not yet developed in these younger patients. Alternatively, older patients with retinopathy may be underrepresented secondary to increased mortality among these patients at a younger age (survivorship bias. Further research is needed to

  4. Facing Contrast-Enhancing Gliomas: Perfusion MRI in Grade III and Grade IV Gliomas according to Tumor Area

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    Anna Luisa Di Stefano

    2014-01-01

    Full Text Available Tumoral neoangiogenesis characterizes high grade gliomas. Relative Cerebral Blood Volume (rCBV, calculated with Dynamic Susceptibility Contrast (DSC Perfusion-Weighted Imaging (PWI, allows for the estimation of vascular density over the tumor bed. The aim of the study was to characterize putative tumoral neoangiogenesis via the study of maximal rCBV with a Region of Interest (ROI approach in three tumor areas—the contrast-enhancing area, the nonenhancing tumor, and the high perfusion area on CBV map—in patients affected by contrast-enhancing glioma (grades III and IV. Twenty-one patients were included: 15 were affected by grade IV and 6 by grade III glioma. Maximal rCBV values for each patient were averaged according to glioma grade. Although rCBV from contrast-enhancement and from nonenhancing tumor areas was higher in grade IV glioma than in grade III (5.58 and 2.68; 3.01 and 2.2, resp., the differences were not significant. Instead, rCBV recorded in the high perfusion area on CBV map, independently of tumor compartment, was significantly higher in grade IV glioma than in grade III (7.51 versus 3.78, P=0.036. In conclusion, neoangiogenesis encompasses different tumor compartments and CBV maps appear capable of best characterizing the degree of neovascularization. Facing contrast-enhancing brain tumors, areas of high perfusion on CBV maps should be considered as the reference areas to be targeted for glioma grading.

  5. Atmosphere of Mars - Mariner IV models compared.

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    Eshleman, V. R.; Fjeldbo, G.; Fjeldbo, W. C.

    1966-01-01

    Mariner IV models of three Mars atmospheric layers analogous to terrestrial E, F-1 and F-2 layers, considering relative mass densities, temperatures, carbon dioxide photodissociation and ionization profile

  6. Specific expression profile and prognostic significance of peroxiredoxins in grade II-IV astrocytic brain tumors

    OpenAIRE

    Kinnula Vuokko L; Parkkila Seppo; Kallio Heini; Rodriguez Alejandra; Rantala Immo; Järvelä Sally; Soini Ylermi; Haapasalo Hannu

    2010-01-01

    Abstract Background Peroxiredoxins (Prxs) have recently been suggested to have a role in tumorigenesis. Methods We studied the expression of Prx I-VI and their relationship to patient survival in 383 grade II-IV diffuse astrocytic brain tumors. Results Prx I positivity was found in 68%, Prx II in 84%, Prx III in 90%, Prx IV in 5%, Prx V in 4% and Prx VI in 47% of the tumors. Prx I and Prx II expression decreased significantly with increasing malignancy grade (p < 0.001 and p < 0.001). Patient...

  7. Type IV Wind Turbine Model

    DEFF Research Database (Denmark)

    Hansen, Anca Daniela; Margaris, Ioannis D.

    project to be incorporated in the wind power plant level. This document describes the Type 4 wind turbine simulation model, implemented in the EaseWind project. The implemented wind turbine model is one of the initial necessary steps toward integrating new control services in the wind power plant level....... In the project, this wind turbine model will be further incorporated in a wind power plant model together with the implementation in the wind power control level of the new control functionalities (inertial response, synchronising power and power system damping). For this purpose an aggregate wind power plant...... (WPP) will be considered. The aggregate WPP model, which will be based on the upscaling of the individual wind turbine model on the electrical part, will make use of an equivalent wind speed. The implemented model follows the basic structure of the generic standard Type 4 wind turbine model proposed...

  8. Grade IV frostbite requiring bilateral below knee amputations: a case report.

    Science.gov (United States)

    Ramdass, Michael J

    2009-04-08

    A rare case of grade IV frostbite is presented resulting in bilateral below knee amputations. This case highlights the importance of early versus late amputation as well as the importance of close collaboration between the rehabilitation, surgical, psychosocial, and public health disciplines in this rare and challenging problem that still may be encountered in the United Kingdom.

  9. Grade IV frostbite requiring bilateral below knee amputations: a case report

    OpenAIRE

    Michael J. Ramdass

    2009-01-01

    A rare case of grade IV frostbite is presented resulting in bilateral below knee amputations. This case highlights the importance of early versus late amputation as well as the importance of close collaboration between the rehabilitation, surgical, psychosocial, and public health disciplines in this rare and challenging problem that still may be encountered in the United Kingdom.

  10. CD133 identifies perivascular niches in grade II-IV astrocytomas

    DEFF Research Database (Denmark)

    Christensen, Karina; Schrøder, Henrik; Kristensen, Bjarne

    2008-01-01

    The aim of the present study was to investigate the localization and distribution of the putative brain tumour stem cell marker CD133 in formalin fixed paraffin embedded astrocytomas. A retrospective analysis of 114 grade II, III and IV astrocytomas was undertaken. The immunohistochemical...

  11. Predictors of successful non-operative management of grade III & IV blunt pancreatic trauma

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    Suman B Koganti

    2016-09-01

    Conclusions: Non-operative measures should be attempted in a select group of grade III&IV blunt pancreatic trauma. In hemodynamically stable patients with a controlled leak walled off as a pseudocyst without associated organ injuries and pancreatic necrosis, NOM has a higher success rate.

  12. Specific expression profile and prognostic significance of peroxiredoxins in grade II-IV astrocytic brain tumors

    Directory of Open Access Journals (Sweden)

    Kinnula Vuokko L

    2010-03-01

    Full Text Available Abstract Background Peroxiredoxins (Prxs have recently been suggested to have a role in tumorigenesis. Methods We studied the expression of Prx I-VI and their relationship to patient survival in 383 grade II-IV diffuse astrocytic brain tumors. Results Prx I positivity was found in 68%, Prx II in 84%, Prx III in 90%, Prx IV in 5%, Prx V in 4% and Prx VI in 47% of the tumors. Prx I and Prx II expression decreased significantly with increasing malignancy grade (p Conclusion The expression of Prx I and Prx II correlates with astrocytic tumor features, such as grade and patient age and proliferation activity (Prx I, and accordingly with patient survival.

  13. Reconstruction of Kuwada grade IV chronic achilles tendon rupture by minimally invasive technique

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    Miao, Xudong; Wu, Yongping; Tao, Huimin; Yang, Disheng; Huang, Lu

    2016-01-01

    Background: Transfer of a flexor hallucis longus (FHL) tendon can not only reconstruct the Achilles tendon but also provide ischemic tendinous tissues with a rich blood supply to enhance wound healing. This retrospective study aims to investigate clinical outcomes in patients who underwent repair of Kuwada grade IV chronic Achilles tendon rupture with long hallucis longus tendons harvested using a minimally invasive technique. Materials and Methods: 35 patients who were treated for Kuwada grade IV Achilles tendon injuries from July 2006 to June 2011 were included in this retrospective study. The age ranged between 23 and 71 years. The duration from primary injury to surgery ranged from 29 days to 34 months (mean value, 137.6 days). All 35 patients had difficulties in lifting their calves. Thirty two were followed up for a mean 32.2 months (range 18–72 months), whereas three were lost to followup. Magnetic resonance imaging (MRI) showed that the tendon rupture gap ranged from 6.0 to 9.2 cm. During surgery, a 2.0 cm minor incision was made vertically in the medial plantar side of the midfoot, and a 1.5 cm minor transverse incision was made in the plantar side of the interphalangeal articulation of the great toe to harvest the FHL tendon, and the tendon was fixed to the calcaneus with suture anchors. Postoperative appearance and function were evaluated by physiotherapists based American Orthopedic Foot and Ankle Society-ankle and hindfoot score (AOFAS-AH), and Leppilahti Achilles tendon ratings. Results: Results were assessed in 32 patients. Except for one patient who suffered complications because of wound disruption 10 days after the operation, all other patients had primary wound healing, with 28 of 32 able to go up on their toes at last followup. The AOFAS-AH score was increased from preoperative (51.92 ± 7.08) points to (92.56 ± 6.71) points; Leppilahti Achilles tendon score was increased from preoperative (72.56 ± 7.43) to (92.58 ± 5.1). There were

  14. Results of treatment of grades IV and V vesicoureteral reflux with endoscopic injection of polyacrylate polyalcohol copolymer

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    Ricardo eSoria

    2013-10-01

    Full Text Available Purpose: Here we report the results of a review of a prospectively maintained database of the use polyacrylate polyalcohol copolymer (PPC injection to correct grades IV and V VUR.Materials and methods: All children with grades IV and V primary VUR that presented with febrile urinary tract infection while on prophylaxis, in a three -year period, were treated with a subureteral injection of PPC. Institutional ethical approval was obtained. Exclusion criteria were incomplete bladder emptying documented on videourodynamic study, ureteral duplication, paraureteral diverticula and poor ureteral emptying observed during fluoroscopy and previous open surgical or endoscopic treatment. Pre- and post-operative evaluation included urinalysis, renal and bladder ultrasonography, DMSA scan and videourodynamic studies.Results: 33 children (36 renal units were included with a median age of 57 months (range 7 to 108. There were 18 males and 15 girls. 30 renal units had grade IV and 6 grade V VUR. Median follow-up time was 32 months (range 7 to 58. Reflux was cured in 32/36 renal units with the first injection, but another 2 patients were reimplanted because of dilatation. Complications included early urinary tract infection in 7 children, transient lower urinary tract symptoms in 5 children. Progressive ureteral dilatation was noted in 4 children and was treated with insertion of a double J stent. Two of these children eventually required an ureteroneocystostomy. Conclusions: The use of PPC to treat grades IV and V vesicoureteral reflux in young children has an overall success rate of 83,3%. Persistent ureteral dilatation was present in 11% associated with high injection volume.Future studies will attempt to maintain a high success rate reducing the volume of injection and the incidence of dilatation.

  15. To nearly come full circle: Nonoperative management of high-grade IV-V blunt splenic trauma is safe using a protocol with routine angioembolization.

    Science.gov (United States)

    Bhullar, Indermeet S; Tepas, Joseph J; Siragusa, Daniel; Loper, Todd; Kerwin, Andrew; Frykberg, Eric R

    2017-04-01

    Nonoperative management (NOM) of hemodynamically stable high-grade (IV-V) blunt splenic trauma remains controversial given the high failure rates (19%) that persist despite angioembolization (AE) protocols. The NOM protocol was modified in 2011 to include mandatory AE of all grade (IV-V) injuries without contrast blush (CB) along with selective AE of grade (I-V) with CB. The purpose of this study was to determine if this new AE (NAE) protocol significantly lowered the failure rates for grade (IV-V) injuries allowing for safe observation without surgery and if the exclusion of grade III injuries allowed for the prevention of unnecessary angiograms without affecting the overall failure rates. The records of patients with blunt splenic trauma from January 2000 to October 2014 at a Level I trauma center were retrospectively reviewed. Patients were divided into two groups and failure of NOM (FNOM) rates compared: NAE protocol (2011-2014) with mandatory AE for all grade (IV-V) injuries without CB and selective AE for grade (I-V) with CB versus old AE (OAE) protocol (2000-2010) with selective AE for grade (I-V) with CB. Seven hundred twelve patients underwent NOM with 522 (73%) in the OAE group and 190 (27%) in the NAE group. Evolving from the OAE to the NAE strategy resulted in a significantly lower FNOM rate for the overall group (grade I-V) (OAE vs. NAE, 4% to 1%, p = 0.04) and the grade (IV-V) group (OAE vs. NAE, 19% vs. 3%, p = 0.01). Angiograms were avoided in 113 grade (I-III) injuries with no CB; these patients had NOM with observation alone and none failed. A protocol using mandatory AE of all high-grade (IV-V) injuries without CB and selective AE of grade (I-V) with CB may provide for optimum salvage with safe NOM of the high-grade injuries (IV-V) and limited unnecessary angiograms. Therapeutic study, level IV.

  16. Data Modelling with First-Grade Students

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    English, Lyn D.

    2012-01-01

    This paper argues for a renewed focus on statistical reasoning in the beginning school years, with opportunities for children to engage in data modelling. Results are reported from the first year of a 3-year longitudinal study in which three classes of first-grade children (6-year-olds) and their teachers engaged in data modelling activities. The…

  17. Micromechanical models for graded composite materials

    DEFF Research Database (Denmark)

    Reiter, T; Dvorak, G.J.; Tvergaard, Viggo

    1997-01-01

    Elastic response of selected plane-array models of graded composite microstructures is examined under both uniform and linearly varying boundary tractions and displacements, by means of detailed finite element studies of large domains containing up to several thousand inclusions. Models consisting...... fields are predicted by Mori-Tanaka estimates. On the other hand, the response of graded materials with a skeletal microstructure in a wide transition zone between clearly defined matrix phases is better approximated by the self-consistent estimates. Certain exceptions are noted for loading by overall...

  18. Graded CTL Model Checking for Test Generation

    CERN Document Server

    Napoli, Margherita

    2011-01-01

    Recently there has been a great attention from the scientific community towards the use of the model-checking technique as a tool for test generation in the simulation field. This paper aims to provide a useful mean to get more insights along these lines. By applying recent results in the field of graded temporal logics, we present a new efficient model-checking algorithm for Hierarchical Finite State Machines (HSM), a well established symbolism long and widely used for representing hierarchical models of discrete systems. Performing model-checking against specifications expressed using graded temporal logics has the peculiarity of returning more counterexamples within a unique run. We think that this can greatly improve the efficacy of automatically getting test cases. In particular we verify two different models of HSM against branching time temporal properties.

  19. Early Grade Writing Assessment: An Instrument Model

    Science.gov (United States)

    Jiménez, Juan E.

    2017-01-01

    The United Nations Educational, Scientific, and Cultural Organization promoted the creation of a model instrument for individual assessment of students' foundational writing skills in the Spanish language that was based on a literature review and existing writing tools and assessments. The purpose of the "Early Grade Writing Assessment"…

  20. Probabilistic Modeling of Graded Timber Material Properties

    DEFF Research Database (Denmark)

    Faber, M. H.; Köhler, J.; Sørensen, John Dalsgaard

    2004-01-01

    The probabilistic modeling of timber material characteristics is considered with special emphasis to the modeling of the effect of different quality control and selection procedures used as means for quality grading in the production line. It is shown how statistical models may be established...... an important role in the overall probabilistic modeling. Therefore a scheme for estimating the parameters of probability distribution parameters focusing on the tail behavior has been established using a censored Maximum Likelihood estimation technique. The proposed probabilistic models have been formulated...

  1. Modeling of functionally graded piezoelectric ultrasonic transducers.

    Science.gov (United States)

    Rubio, Wilfredo Montealegre; Buiochi, Flávio; Adamowski, Julio Cezar; Silva, Emílio Carlos Nelli

    2009-05-01

    The application of functionally graded material (FGM) concept to piezoelectric transducers allows the design of composite transducers without interfaces, due to the continuous change of property values. Thus, large improvements can be achieved, as reduction of stress concentration, increasing of bonding strength, and bandwidth. This work proposes to design and to model FGM piezoelectric transducers and to compare their performance with non-FGM ones. Analytical and finite element (FE) modeling of FGM piezoelectric transducers radiating a plane pressure wave in fluid medium are developed and their results are compared. The ANSYS software is used for the FE modeling. The analytical model is based on FGM-equivalent acoustic transmission-line model, which is implemented using MATLAB software. Two cases are considered: (i) the transducer emits a pressure wave in water and it is composed of a graded piezoceramic disk, and backing and matching layers made of homogeneous materials; (ii) the transducer has no backing and matching layer; in this case, no external load is simulated. Time and frequency pressure responses are obtained through a transient analysis. The material properties are graded along thickness direction. Linear and exponential gradation functions are implemented to illustrate the influence of gradation on the transducer pressure response, electrical impedance, and resonance frequencies.

  2. The influence of polypharmacy on grade III/IV toxicity, prior discontinuation of chemotherapy and overall survival in ovarian cancer.

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    Woopen, H; Richter, R; Ismaeel, F; Chekerov, R; Roots, I; Siepmann, T; Sehouli, J

    2016-03-01

    Ovarian cancer is mostly diagnosed in the elderly woman who is likely to have comorbid disease and to take several comedications on a regular basis. Aim of this study was to evaluate the influence of polypharmacy on grade III/IV toxicity, prior discontinuation of chemotherapy and survival. In this individual participant data meta-analysis the original data of three phase II/III studies of the North-Eastern German Society of Gynecological Oncology (NOGGO) were analyzed using multivariate logistic and Cox regression. Overall, 1213 patients with recurrent ovarian cancer were included in these analyses. An increasing amount of medication was associated with overall grade III/IV toxicity (ppolypharmacy with overall survival (p=0.068). As polypharmacy does not influence survival ovarian cancer patients taking several comedications may be included in clinical trials and should not be deprived of adequate cancer treatment. However, a thorough monitoring is mandatory due to the increased risk of toxicities. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Comparative study of different treatment options of grade III and IV diabetic foot ulcers to reduce the incidence of amputations

    Directory of Open Access Journals (Sweden)

    Poras Chaudhary

    2013-02-01

    Full Text Available This study aims to compare the efficacy of antiseptic dressings, hyperbaric oxygen therapy, and recombinant human platelet derived growth factor (rhPDGF for two reasons: i to reduce the incidence of lower limb amputations in diabetic foot ulcer; ii to limit the duration of stay in the hospital. A prospective randomized trial was conducted on 60 patients with stage III and IV diabetic foot ulcers (International Association of Enterostomal Therapy classification and patients were divided randomly in three different therapy groups - antiseptics, hyperbaric oxygen therapy, recombinant platelet derived growth factor, with 20 patients in each group. Patients were managed initially on inpatient and then on outpatient basis till the ulcer healed completely. Results among three groups were compared using unpaired T test and the level of significance was set at P<0.05 using ANOVA. This study compares the efficacy of hyperbaric oxygen therapy, antiseptic dressings, and rhPDGF in grade III and IV diabetic foot ulcers. P value (0.0348 was significant for complete wound contraction while p value healing time (0.6534 and ulcer size (0.0593 in the groups was not significant. PDGF is safe, effective and easy to apply. Results are comparable with hyperbaric oxygen (HBO therapy and cost of treatment is lower than other therapies. Diabetic foot ulcer management requires multidisciplinary and aggressive approach. PDGF should be recommended for all grade III and IV diabetic foot ulcer at least 8 weeks old. HBO is equally good an option but has limitations and side effects.

  4. Africa South of the Sahara. Grade Twelve. [Resource Unit IV.] Project Social Studies.

    Science.gov (United States)

    Minnesota Univ., Minneapolis. Project Social Studies Curriculum Center.

    This is the fourth of seven resource units for a twelfth grade course on value conflicts and policy decisions. The topic for this unit is Africa south of the Sahara. The objectives are listed as to generalizations, skills, and values. The double-page format relates objectives to pertinent content, teaching procedures, and instructional materials.…

  5. Intriguing Animals. Language Arts Theme Units, Volume IV. Cross Curricular Activities for Primary Grades.

    Science.gov (United States)

    McAllister, Elizabeth A.; Hildebrand, Joan M.; Ericson, Joann H.

    Suggesting that students in the primary grades can explore the world around them and practice valuable skills in spelling, reading, writing, communication, and language, this book presents cross-curricular units on intriguing animals that reach diverse needs by working through emotional memory, deductive reasoning, and multiple intelligences.…

  6. Structure activity relationship modelling of milk protein-derived peptides with dipeptidyl peptidase IV (DPP-IV) inhibitory activity.

    Science.gov (United States)

    Nongonierma, Alice B; FitzGerald, Richard J

    2016-05-01

    Quantitative structure activity type models were developed in an attempt to predict the key features of peptide sequences having dipeptidyl peptidase IV (DPP-IV) inhibitory activity. The models were then employed to help predict the potential of peptides, which are currently reported in the literature to be present in the intestinal tract of humans following milk/dairy product ingestion, to act as inhibitors of DPP-IV. Two models (z- and v-scale) for short (2-5 amino acid residues) bovine milk peptides, behaving as competitive inhibitors of DPP-IV, were developed. The z- and the v-scale models (p<0.05, R(2) of 0.829 and 0.815, respectively) were then applied to 56 milk protein-derived peptides previously reported in the literature to be found in the intestinal tract of humans which possessed a structural feature of DPP-IV inhibitory peptides (P at the N2 position). Ten of these peptides were synthetized and tested for their in vitro DPP-IV inhibitory properties. There was no agreement between the predicted and experimentally determined DPP-IV half maximal inhibitory concentrations (IC50) for the competitive peptide inhibitors. However, the ranking for DPP-IV inhibitory potency of the competitive peptide inhibitors was conserved. Furthermore, potent in vitro DPP-IV inhibitory activity was observed with two peptides, LPVPQ (IC50=43.8±8.8μM) and IPM (IC50=69.5±8.7μM). Peptides present within the gastrointestinal tract of human may have promise for the development of natural DPP-IV inhibitors for the management of serum glucose.

  7. Early Grade Writing Assessment: An Instrument Model.

    Science.gov (United States)

    Jiménez, Juan E

    2016-03-17

    The United Nations Educational, Scientific, and Cultural Organization promoted the creation of a model instrument for individual assessment of students' foundational writing skills in the Spanish language that was based on a literature review and existing writing tools and assessments. The purpose of the Early Grade Writing Assessment (EGWA) is to document learners' basic writing skills, mapped in composing units of increasing complexity to communicate meaning. Validation and standardization of EGWA was conducted in the Canary Islands (Spain) in 12 schools using a cross-sectional design with a sample of 1,653 Spanish-speaking students in Grades 1 through 3. The author describes EGWA's internal structure, along with the prevalence of learning disabilities (LD) in transcription and developmental differences in writing between Spanish-speaking children with LD and typical peers. Findings suggest that EGWA's psychometric characteristics are satisfactory, and its internal structure can be attributed to four factors responsible for a high percentage of the variance. The odds ratio indicated that 2 Spanish-speaking children with LD in transcription are identified out of every 100. A comparison between students with and without LD in transcription revealed statistically significant differences concerning sentence and text production across grades. Results are interpreted within current theoretical accounts of writing models.

  8. Modeling of vibration for functionally graded beams

    Directory of Open Access Journals (Sweden)

    Yiğit Gülsemay

    2016-01-01

    Full Text Available In this study, a vibration problem of Euler-Bernoulli beam manufactured with Functionally Graded Material (FGM, which is modelled by fourth-order partial differential equations with variable coefficients, is examined by using the Adomian Decomposition Method (ADM.The method is one of the useful and powerful methods which can be easily applied to linear and nonlinear initial and boundary value problems. As to functionally graded materials, they are composites mixed by two or more materials at a certain rate. This mixture at a certain rate is expressed with an exponential function in order to try to minimize singularities from transition between different surfaces of materials as much as possible. According to the structure of the ADM in terms of initial conditions of the problem, a Fourier series expansion method is used along with the ADM for the solution of simply supported functionally graded Euler-Bernoulli beams. Finally, by choosing an appropriate mixture rate for the material, the results are shown in figures and compared with those of a standard (homogeneous Euler-Bernoulli beam.

  9. Modeling of dimensionally graded magnetoelectric energy harvester

    Energy Technology Data Exchange (ETDEWEB)

    Petrov, R.V., E-mail: Roman.Petrov@novsu.ru [Department of Design and Technology of Radio equipment, Novgorod State University, Veliky Novgorod (Russian Federation); Petrov, V.M.; Bichurin, M.I. [Department of Design and Technology of Radio equipment, Novgorod State University, Veliky Novgorod (Russian Federation); Zhou, Y.; Priya, S. [Virginia Polytechnic Institute and State University, Bio-Inspired Materials and Devices Laboratory, Center for Energy Harvesting Materials and Systems, Blacksburg, VA 24061 (United States)

    2015-06-01

    The magnetoelectric behavior of a dual-phase dimensionally graded magnetostrictive-piezoelectric composite is modeled in this article. The cantilever is formed by piezoelectric macro-fiber composite bonded to a Ni cantilever. Theoretical estimates show a large magnetoelectric voltage coefficient of 100 V/(cm Oe) at electromechanical resonance frequency. An additive effect was realized when an acceleration and magnetic field was applied to the structure simultaneously. Applied magnetic field of 10 Oe and shaker acceleration of 0.02 g induce the approximately equal output voltage of 20–35 V.

  10. A pilot randomised controlled trial of negative pressure wound therapy to treat grade III/IV pressure ulcers [ISRCTN69032034

    Science.gov (United States)

    2012-01-01

    Background Negative pressure wound therapy (NPWT) is widely promoted as a treatment for full thickness wounds; however, there is a lack of high-quality research evidence regarding its clinical and cost effectiveness. A trial of NPWT for the treatment of grade III/IV pressure ulcers would be worthwhile but premature without assessing whether such a trial is feasible. The aim of this pilot randomised controlled trial was to assess the feasibility of conducting a future full trial of NPWT for the treatment of grade III and IV pressure ulcers and to pilot all aspects of the trial. Methods This was a two-centre (acute and community), pilot randomised controlled trial. Eligible participants were randomised to receive either NPWT or standard care (SC) (spun hydrocolloid, alginate or foam dressings). Outcome measures were time to healing of the reference pressure ulcer, recruitment rates, frequency of treatment visits, resources used and duration of follow-up. Results Three hundred and twelve patients were screened for eligibility into this trial over a 12-month recruitment period and 12/312 participants (3.8%) were randomised: 6 to NPWT and 6 to SC. Only one reference pressure ulcer healed (NPWT group) during follow-up (time to healing 79 days). The mean number of treatment visits per week was 3.1 (NPWT) and 5.7 (SC); 6/6 NPWT and 1/6 SC participants withdrew from their allocated trial treatment. The mean duration of follow-up was 3.8 (NPWT) and 5.0 (SC) months. Conclusions This pilot trial yielded vital information for the planning of a future full study including projected recruitment rate, required duration of follow-up and extent of research nurse support required. Data were also used to inform the cost-effectiveness and value of information analyses, which were conducted alongside the pilot trial. Trial registration Current Controlled Trials ISRCTN69032034. PMID:22839453

  11. A pilot randomised controlled trial of negative pressure wound therapy to treat grade III/IV pressure ulcers [ISRCTN69032034

    Directory of Open Access Journals (Sweden)

    Ashby Rebecca L

    2012-07-01

    Full Text Available Abstract Background Negative pressure wound therapy (NPWT is widely promoted as a treatment for full thickness wounds; however, there is a lack of high-quality research evidence regarding its clinical and cost effectiveness. A trial of NPWT for the treatment of grade III/IV pressure ulcers would be worthwhile but premature without assessing whether such a trial is feasible. The aim of this pilot randomised controlled trial was to assess the feasibility of conducting a future full trial of NPWT for the treatment of grade III and IV pressure ulcers and to pilot all aspects of the trial. Methods This was a two-centre (acute and community, pilot randomised controlled trial. Eligible participants were randomised to receive either NPWT or standard care (SC (spun hydrocolloid, alginate or foam dressings. Outcome measures were time to healing of the reference pressure ulcer, recruitment rates, frequency of treatment visits, resources used and duration of follow-up. Results Three hundred and twelve patients were screened for eligibility into this trial over a 12-month recruitment period and 12/312 participants (3.8% were randomised: 6 to NPWT and 6 to SC. Only one reference pressure ulcer healed (NPWT group during follow-up (time to healing 79 days. The mean number of treatment visits per week was 3.1 (NPWT and 5.7 (SC; 6/6 NPWT and 1/6 SC participants withdrew from their allocated trial treatment. The mean duration of follow-up was 3.8 (NPWT and 5.0 (SC months. Conclusions This pilot trial yielded vital information for the planning of a future full study including projected recruitment rate, required duration of follow-up and extent of research nurse support required. Data were also used to inform the cost-effectiveness and value of information analyses, which were conducted alongside the pilot trial. Trial registration Current Controlled Trials ISRCTN69032034.

  12. Modeling Individual Subtests of the WAIS IV with Multiple Latent Factors: e74980

    National Research Council Canada - National Science Library

    Dennis J McFarland

    2013-01-01

    ... multidimensional models of the Wechsler Adult Intelligence Scales- fourth edition (WAIS-IV) subtests. Multidimensional models of subtest performance provided better model fit as compared to several...

  13. Modeling individual subtests of the WAIS IV with multiple latent factors

    National Research Council Canada - National Science Library

    McFarland, Dennis J

    2013-01-01

    ... multidimensional models of the Wechsler Adult Intelligence Scales-fourth edition (WAIS-IV) subtests. Multidimensional models of subtest performance provided better model fit as compared to several...

  14. Modeling Bamboo as a Functionally Graded Material

    Science.gov (United States)

    Silva, Emílio Carlos Nelli; Walters, Matthew C.; Paulino, Glaucio H.

    2008-02-01

    Natural fibers are promising for engineering applications due to their low cost. They are abundantly available in tropical and subtropical regions of the world, and they can be employed as construction materials. Among natural fibers, bamboo has been widely used for housing construction around the world. Bamboo is an optimized composite material which exploits the concept of Functionally Graded Material (FGM). Biological structures, such as bamboo, are composite materials that have complicated shapes and material distribution inside their domain, and thus the use of numerical methods such as the finite element method and multiscale methods such as homogenization, can help to further understanding of the mechanical behavior of these materials. The objective of this work is to explore techniques such as the finite element method and homogenization to investigate the structural behavior of bamboo. The finite element formulation uses graded finite elements to capture the varying material distribution through the bamboo wall. To observe bamboo behavior under applied loads, simulations are conducted considering a spatially-varying Young's modulus, an averaged Young's modulus, and orthotropic constitutive properties obtained from homogenization theory. The homogenization procedure uses effective, axisymmetric properties estimated from the spatially-varying bamboo composite. Three-dimensional models of bamboo cells were built and simulated under tension, torsion, and bending load cases.

  15. Strategy Guideline: Modeling Enclosure Design in Above-Grade Walls

    Energy Technology Data Exchange (ETDEWEB)

    Lstiburek, J. [Building Science Corporation, Westford, MA (United States); Ueno, K. [Building Science Corporation, Westford, MA (United States); Musunuru, S. [Building Science Corporation, Westford, MA (United States)

    2016-02-24

    The Strategy Guideline describes how to model and interpret results of models for above grade walls. The Measure Guideline analyzes the failure thresholds and criteria for above grade walls. A library of above-grade walls with historically successful performance was used to calibrate WUFI (Warme Und Feuchte Instationar) software models. The information is generalized for application to a broad population of houses within the limits of existing experience.

  16. Evaluation of multidimensional models of WAIS-IV subtest performance.

    Science.gov (United States)

    McFarland, Dennis J

    2017-04-21

    The present study examined the extent to which the covariance structure of the WAIS-IV is best accounted for by models that assume that test performance is the result of group-level factors and multiple independent general factors. Structural models with one to four general factors were evaluated with either four or five group-level factors. Simulations based on four general factors were run to clarify the adequacy of the estimates of the allocation of covariance by the models. Four independent general factors provided better fit than a single general factor for either model with four or five group-level factors. While one of the general factors had much larger loadings than all other factors, simulation results suggested that this might be an artifact of the statistical procedure rather than a reflection of the nature of individual differences in cognitive abilities. These results argue against the contention that clinical interpretation of cognitive test batteries should primarily be at the level of general intelligence. It is a fallacy to assume that factor analysis can reveal the structure of human abilities. Test validity should not be based solely on the results of modeling the covariance of test batteries.

  17. Chromospheric models for Altair (A7 IV-V)

    Science.gov (United States)

    Ferrero, R. Freire; Gouttebroze, P.; Catalano, S.; Marilli, E.; Bruhweiler, F.; Kondo, Y.; Van Der Hucht, K.; Talavera, A.

    1995-01-01

    The star, Altair (A7 IV-V), is clearly shown to have Lyman-alpha emission of chromospheric origin, while no evidence is found for the Mg II emission reported in previous investigations. We present non-Local Thermodymanic Equilibrium (non-LTE) semiempirical models incorporating partial redistribution of the chromosphere of Altair that reproduce the observed Lyman-alpha emission and the Mg II resonance absorption at 2800 A. We unambiguously establihed that chromospheres exist at spectral types as early as A7 on the main sequence, and we also demonstrate that it very unlikely that the observed emission originates in a corotating expanding wind. This result represents a new challenge for chromospheric heating theories. It may indicate that both differential rotation and convection layers, at least near the equator, exist in this fast rotating (v sin i = 220 km/s) star.

  18. The Effect of Constructivist Learning Using Scientific Approach on Mathematical Power and Conceptual Understanding of Students Grade IV

    Science.gov (United States)

    Kusmaryono, Imam; Suyitno, Hardi

    2016-02-01

    This study used a model of Concurrent Embedded with the aim of: (1) determine the difference between the conceptual understanding and mathematical power of students grade fourth who take the constructivist learning using scientific approach and direct learning, (2) determine the interaction between learning approaches and initial competence on the mathematical power and conceptual of understanding, and (3) describe the mathematical power of students grade fourth. This research was conducted in the fourth grade elementary school early 2015. Data initial competence and mathematical power obtained through tests, and analyzed using statistical tests multivariate and univariate. Statistical analysis of the results showed that: (1) There are differences in the concept of understanding and mathematical power among the students who follow the scientifically-based constructivist learning than students who take the Direct Learning in terms of students initial competency (F = 5.550; p = 0.007 skills. Researcher suggested that the learning of mathematics in schools using scientifically- based constructivist approach to improve the mathematical power of students and conceptual understanding.

  19. Bifactor Modeling and the Estimation of Model-Based Reliability in the WAIS-IV

    Science.gov (United States)

    Gignac, Gilles E.; Watkins, Marley W.

    2013-01-01

    Previous confirmatory factor analytic research that has examined the factor structure of the Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) has endorsed either higher order models or oblique factor models that tend to amalgamate both general factor and index factor sources of systematic variance. An alternative model that has not yet…

  20. Bifactor Modeling and the Estimation of Model-Based Reliability in the WAIS-IV

    Science.gov (United States)

    Gignac, Gilles E.; Watkins, Marley W.

    2013-01-01

    Previous confirmatory factor analytic research that has examined the factor structure of the Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) has endorsed either higher order models or oblique factor models that tend to amalgamate both general factor and index factor sources of systematic variance. An alternative model that has not yet…

  1. Application of skin traction for surgical treatment of grade IV pressure sore: a clinical report of 160 cases.

    Science.gov (United States)

    Chen, X; Jiang, Z; Chen, Z; Wang, D

    2011-01-01

    Retrospective clinical study. To assess the method of primary surgical closure of pressure sores developed by the Ruixin Hospital for burns. Nanjing, China. The study included 235 grade IV pressure sores of 160 patients, M:F = 119:41. Their age ranged from 19 to 93 years (mean = 47.4, s.d. ± 15.7). The primary disease was spinal cord injury in 141 patients (88.1%). The location of sore spread over ischial, sacrococcygeal and trochanteric regions. The largest pressure sore measured 15 × 25 cm(2). The time from onset of sore to admission ranged from 3 months to 22 years (mean = 35.5 months, s.d. ± 55.8). Local preoperative preparation included external skin traction using adhesive tapes, wound cleaning and change of dressing. General condition was checked and improved by supportive measures. Operation procedures included thorough debridement, excision of hidden minor scars, mobilizing opposing skin flaps and meticulous haemostasis before closure. Skin traction continued after the operation until the wound was healed. All but 10 sores healed primarily. These 10 sores healed after a revision. The length of stay in hospital ranged from 20 to 140 days (mean = 45.1 days, s.d. ± 21.1). Follow-up period was 2-51 months (mean = 22 months, s.d. ± 12.5). Two ischial sores recurred owing to long sitting. They were cured with the same method. Three illustrative cases are presented. The method is simple and enjoys a high success rate with a short stay in hospital and hence is cost effective. The recurrence is rare.

  2. Modelling of advanced structural materials for GEN IV reactors

    Science.gov (United States)

    Samaras, M.; Hoffelner, W.; Victoria, M.

    2007-09-01

    The choice of suitable materials and the assessment of long-term materials damage are key issues that need to be addressed for the safe and reliable performance of nuclear power plants. Operating conditions such as high temperatures, irradiation and a corrosive environment degrade materials properties, posing the risk of very expensive or even catastrophic plant damage. Materials scientists are faced with the scientific challenge to determine the long-term damage evolution of materials under service exposure in advanced plants. A higher confidence in life-time assessments of these materials requires an understanding of the related physical phenomena on a range of scales from the microscopic level of single defect damage effects all the way up to macroscopic effects. To overcome lengthy and expensive trial-and-error experiments, the multiscale modelling of materials behaviour is a promising tool, bringing new insights into the fundamental understanding of basic mechanisms. This paper presents the multiscale modelling methodology which is taking root internationally to address the issues of advanced structural materials for Gen IV reactors.

  3. Endogeneity in Panel Data Models with Time-Varying and Time-Fixed Regressors: To IV or not IV?

    DEFF Research Database (Denmark)

    Mitze, Timo

    We analyse the problem of parameter inconsistency in panel data econometrics due to the correlation of exogenous variables with the error term.A common solution in this setting is to use Instrumental-Variable (IV) estimation in the spirit of Hausman-Taylor (1981). However, some potential...... Carlo simulations, where we explicitly control for the problem of IV selection in the Hausman-Taylor case. The simulation results show that the Hausman- Taylor model with perfect-knowledge about the underlying data structure (instrument orthogonality) has on average the smallest bias. However, compared...... square error (rmse) than both Hausman-Taylor models with perfect and imperfect knowledge about the underlying correlation between r.h.s variables and residual term.This indicates that it is generally more efficient.The results are roughly robust for various combinations in the time and cross...

  4. Asymptotic modelling of some functionally graded materials

    OpenAIRE

    Wozniak, Czeslaw; Wagrowska, Monika

    2010-01-01

    International audience; The object of analysis is a multilayered functionally graded laminated heat conductor. Region occupied by this heat conductor is denoted by Ω=(0, L)× Ξ, where Ξ is a region on the 0ξ1ξ2 plane and x∈(0, L). Region Ω is divided into n layers of the same thicknesses λ ...

  5. Graded Response Modeling of the Quality of Life Interview.

    Science.gov (United States)

    Uttaro, Thomas; Lehman, Anthony

    1999-01-01

    Outlined a graded response model and applied it to an aggregated data set from four studies involving subjective items from the Quality of Life Interview (QOLI) (A. Lehman, 1988). Used the results to create customized QOLI scales. Discusses the use of this methodology for scales involving ordered, graded categories. (SLD)

  6. COBRA-IV: the model and the method

    Energy Technology Data Exchange (ETDEWEB)

    Stewart, C.W.; Wheeler, C.L.; Cena, R.J.; McMonagle, C.A.; Cuta, J.M.; Trent, D.S.

    1977-07-01

    The objective of this report is to present the mathematical basis of the COBRA-IV computer program (Wheeler et al., 1976) being developed by Battelle, Pacific Northwest Laboratory. The COBRA-IV code is an extended version of the COBRA-IIIC subchannel analysis code that computes the flow and enthalpy distributions in nuclear fuel rod bundles and cores for both steady state and transient conditions (Rowe, 1973).

  7. The Relationship between Delivery Models and the Grade-Level Reading Development of Sixth-Grade English Learners

    Science.gov (United States)

    Arnold, Holly Weber

    2013-01-01

    This study examines the relationship between delivery models (the class size reduction model and the sheltered instruction model) and language development levels on the grade-level reading development of sixth-grade English learners (ELs) attending public middle schools in metro Atlanta, Georgia. The instrument used to measure grade-level mastery…

  8. Hybrid graded element model for transient heat conduction in functionally graded materials

    Institute of Scientific and Technical Information of China (English)

    Lei-Lei Cao; Qing-Hua Qin; Ning Zhao

    2012-01-01

    This paper presents a hybrid graded element model for the transient heat conduction problem in functionally graded materials (FGMs).First,a Laplace transform approach is used to handle the time variable.Then,a fundamental solution in Laplace space for FGMs is constructed.Next,a hybrid graded element is formulated based on the obtained fundamental solution and a frame field.As a result,the graded properties of FGMs are naturally reflected by using the fundamental solution to interpolate the intra-element field.Further,Stefest's algorithm is employed to convert the results in Laplace space back into the time-space domain.Finally,the performance of the proposed method is assessed by several benchmark examples.The results demonstrate well the efficiency and accuracy of the proposed method.

  9. Strategy Guideline. Modeling Enclosure Design in Above-Grade Walls

    Energy Technology Data Exchange (ETDEWEB)

    Lstiburek, J. [Building Science Corporation, Westford, MA (United States); Ueno, K. [Building Science Corporation, Westford, MA (United States); Musunuru, S. [Building Science Corporation, Westford, MA (United States)

    2016-02-01

    The Strategy Guideline, written by the U.S. Department of Energy's research team Building Science Corporation, 1) describes how to model and interpret results of models for above-grade walls, and 2) analyzes the failure thresholds and criteria for above-grade walls. A library of above-grade walls with historically successful performance was used to calibrate WUFI (Wärme und Feuchte instationär) software models. The information is generalized for application to a broad population of houses within the limits of existing experience.

  10. Accuracy of high-field intraoperative MRI in the detectability of residual tumor in glioma grade IV resections

    Energy Technology Data Exchange (ETDEWEB)

    Hesselmann, Volker; Mager, Ann-Kathrin [Asklepios-Klinik Nord, Hamburg (Germany). Radiology/Neurologie; Goetz, Claudia; Kremer, Paul [Asklepios-Klinik Nord, Hamburg (Germany). Dept. of Neurosurgery; Detsch, Oliver [Asklepios-Klinik Nord, Hamburg (Germany). Dept. of Anaesthesiology and Intensive Care Medicine; Theisgen, Hannah-Katharina [Universitaetsklinikum Schleswig-Holstein, Kiel (Germany). Dept. of Neurosurgery; Friese, Michael; Gottschalk, Joachim [Asklepios-Klinik Nord, Hamburg (Germany). Dept. of Pathology and Neuropathology; Schwindt, Wolfram [Univ. Hospital Muenster (Germany). Dept. of Clinical Radiology

    2017-06-15

    To assess the sensitivity/specificity of tumor detection by T1 contrast enhancement in intraoperative MRI (ioMRI) in comparison to histopathological assessment as the gold standard in patients receiving surgical resection of grade IV glioblastoma. 68 patients with a primary or a recurrent glioblastoma scheduled for surgery including fluorescence guidance and neuronavigation were included (mean age: 59 years, 26 female, 42 male patients). The ioMRI after the first resection included transverse FLAIR, DWI, T2-FFE and T1 - 3 d FFE ± GD-DPTA. The second resection was performed whenever residual contrast-enhancing tissue was detected on ioMRI. Resected tissue samples were histopathologically evaluated (gold standard). Additionally, we evaluated the early postoperative MRI scan acquired within 48 h post-OP for remaining enhancing tissue and compared them with the ioMRI scan. In 43 patients ioMRI indicated residual tumorous tissue, which could be confirmed in the histological specimens of the second resection. In 16 (4 with recurrent, 12 with primary glioblastoma) cases, ioMRI revealed truly negative results without residual tumor and follow-up MRI confirmed complete resection. In 7 cases (3 with recurrent, 4 with primary glioblastoma) ioMRI revealed a suspicious result without tumorous tissue in the histopathological workup. In 2 (1 for each group) patients, residual tumorous tissue was detected in spite of negative ioMRI. IoMRI had a sensitivity of 95 % (94 % recurrent and 96 % for primary glioblastoma) and a specificity of 69.5 % (57 % and 75 %, respectively). The positive predictive value was 86 % (84 % for recurrent and 87 % for primary glioblastoma), and the negative predictive value was 88 % (80 % and 92 %, respectively). ioMRI is effective for detecting remaining tumorous tissue after glioma resection. However, scars and leakage of contrast agent can be misleading and limit specificity. Intraoperative MRI (ioMRI) presents with a high sensitivity for residual

  11. Effect of Supercoiling on the Mechanical and Permeability Properties of Model Collagen IV Networks.

    Science.gov (United States)

    Gyoneva, Lazarina; Segal, Yoav; Dorfman, Kevin D; Barocas, Victor H

    2015-07-01

    Collagen IV networks in the glomerular basement membrane (GBM) are essential for the maintenance and regulation of blood filtration in the kidneys. The GBM contains two different types of collagen IV networks: [α1(IV)]2α2(IV) and α3(IV)α4(IV)α5(IV), the latter of which has a higher number of supercoils (two or more collagens coiling around each other). To investigate the effects of supercoiling on the mechanical and permeability properties of collagen IV networks, we generated model collagen IV networks in the GBM and reconnected them to create different levels of supercoiling. We found that supercoiling greatly increases the stiffness of collagen IV networks but only minimally decreases the permeability. Also, doubling the amount of supercoils in a network had a bigger effect than doubling the stiffness of the supercoils. Our results suggest that the formation of supercoils is a specialized mechanism by the GBM that provides with a network stiff and strong enough to withstand the high hydrostatic pressures of filtration, yet porous enough that filtration is not hindered. Clinically, understanding the effects of supercoiling gives us insight into the mechanisms of GBM failure in some disease states where the normal collagen IV structure is disrupted.

  12. Simple grading model for financial markets

    Science.gov (United States)

    Thuy Anh, Chu; Lan, Nguyen Tri; Viet, Nguyen Ai

    2015-06-01

    A simple way to estimate and grade a financial market by comparison the evolution process and the shape of distribution functions was proposed. In normal working state of financial market, the shape of distribution functions have one-peak form and change from Boltzmann-like to Gaussian-like distributions, while in risk moment might have two-peak form. The grad of financial markets was characterized by overlap area of initial and final distribution functions, and for risk degree by the separation between two shoulders of distribution function. The meaning of Levi tails of distribution and laws of general entropy and information was discussed.

  13. Thermodynamic effects after Diode and Er:YAG laser irradiation of grade IV and V titanium implants placed in bone - an ex vivo study. Preliminary report.

    Science.gov (United States)

    Matys, Jacek; Botzenhart, Ute; Gedrange, Tomasz; Dominiak, Marzena

    2016-10-01

    Many inserted implants are affected by peri-implantitis. The aim of our study was to evaluate increases in implant temperature, depending on the diameter and chemical composition of implants. In particular we measured the time it takes for the temperature of an implant to rise by 10°C and evaluated laser power settings required to prevent thermal injury when an implant surface is decontaminated during the treatment of peri-implantitis. The study analysed six implants placed in porcine ribs and divided into two groups according to their diameter and chemical composition (grade IV and grade V titanium). The implants were irradiated with Diode and Er:YAG lasers using different laser parameters. The temperature was measured with a K-type thermocouple. The temperature on the implant surface rose as the laser power increased and the implant diameter decreased. The time required to increase the temperature of an implant by 10°C was less than it was for titanium grade IV. The temperature gradient was below 10°C for all implants treated using a laser power up to 1 W. It is important to choose the correct laser parameters, depending on the chemical composition and diameter of the implant, so that decontamination of the implant surface is thorough, effective and safe.

  14. Seventh Grade Students' Mental Models of the Greenhouse Effect

    Science.gov (United States)

    Shepardson, Daniel P.; Choi, Soyoung; Niyogi, Dev; Charusombat, Umarporn

    2011-01-01

    This constructivist study investigates 225 student drawings and explanations from three different schools in the midwest in the US, to identify seventh grade students' mental models of the greenhouse effect. Five distinct mental models were derived from an inductive analysis of the content of the students' drawings and explanations: Model 1, a…

  15. Validation of DSM-IV Model of Psychiatric Syndromes in Children with Autism Spectrum Disorders

    Science.gov (United States)

    Lecavalier, Luc; Gadow, Kenneth D.; DeVincent, Carla J.; Edwards, Michael C.

    2009-01-01

    The objective of this study was to assess the internal construct validity of the DSM-IV as a conceptual model for characterizing behavioral syndromes in children with ASD. Parent and teachers completed the Child Symptom Inventory-4, a DSM-IV-referenced rating scale, for 6-to-12 year old clinic referrals with an ASD (N = 498). Ratings were…

  16. Is there a role for hyperbaric oxygen as primary treatment for grade IV radiation-induced haemorrhagic cystitis? a prospective pilot-feasibility study and review of literature

    Energy Technology Data Exchange (ETDEWEB)

    Dellis, Athanasios [Surgical Department, University of Athens, Aretaieion Hospital (Greece); Deliveliotis, Charalambos [Urologic Department, University of Athens, Sismanoglio General Hospital (Greece); Kalentzos, Vasileios; Vavasis, Pavlos; Skolarikos, Andreas [Diving and Hyperbaric Oxygen Department, Naval and Veterans Hospital, Athens (Greece)

    2014-05-15

    Purpose: To examine the safety and efficacy of hyperbaric oxygen as the primary treatment for Grade IV radiation-induced haemorrhagic cystitis. Materials and Methods: Hyperbaric oxygen was prospectively applied as a primary treatment option in 11 patients with Grade IV radiation cystitis. Primary endpoint was the incidence of complete and partial response to treatment. Secondary endpoints included the duration of response, the correlation of treatment success-rate to the interval between the onset of haematuria and initiation of therapy, blood transfusion need and total radiation dose, the number of sessions to success, the avoidance of surgery and the overall survival. Results: All patients completed therapy without complications for a mean follow-up of 17.82 months (range 3 to 34). Mean number of sessions needed was 32.8 (range 27 to 44). Complete and partial response rate was 81.8% and 18.2%, respectively. However, in three patients the first treatment session was not either sufficient or durable giving a 72.7% rate of durable effect. Interestingly, all 9 patients with complete response received therapy within 6 months of the haematuria onset compared to the two patients with partial response who received therapy at 8 and 10 months from the haematuria onset, respectively (p = 0.018). The need for blood transfusion (p = 0.491) and the total radiation dose (p = 0.259) were not correlated to success-rate. One patient needed cystectomy, while all patients were alive at the end of follow-up. Conclusions: Early primary use of hyperbaric oxygen to treat radiation-induced grade IV cystitis is an effective and safe treatment option. (author)

  17. Is there a role for hyberbaric oxygen as primary treatment for grade IV radiation-induced haemorrhagic cystitis? a prospective pilot-feasibility study and review of literature

    Directory of Open Access Journals (Sweden)

    Athanasios Dellis

    2014-06-01

    Full Text Available Purpose To examine the safety and efficacy of hyperbaric oxygen as the primary treatment for Grade IV radiation-induced haemorrhagic cystitis. Materials and Methods Hyperbaric oxygen was prospectively applied as a primary treatment option in 11 patients with Grade IV radiation cystitis. Primary endpoint was the incidence of complete and partial response to treatment. Secondary endpoints included the duration of response, the correlation of treatment success-rate to the interval between the onset of haematuria and initiation of therapy, blood transfusion need and total radiation dose, the number of sessions to success, the avoidance of surgery and the overall survival. Results All patients completed therapy without complications for a mean follow-up of 17.82 months (range 3 to 34. Mean number of sessions needed was 32.8 (range 27 to 44. Complete and partial response rate was 81.8% and 18.2%, respectively. However, in three patients the first treatment session was not either sufficient or durable giving a 72.7% rate of durable effect. Interestingly, all 9 patients with complete response received therapy within 6 months of the haematuria onset compared to the two patients with partial response who received therapy at 8 and 10 months from the haematuria onset, respectively (p = 0.018. The need for blood transfusion (p = 0.491 and the total radiation dose (p = 0.259 were not correlated to success-rate. One patient needed cystectomy, while all patients were alive at the end of follow-up. Conclusions Early primary use of hyperbaric oxygen to treat radiation-induced grade IV cystitis is an effective and safe treatment option.

  18. 40 CFR Appendix IV to Part 600 - Sample Fuel Economy Labels for 2008 and Later Model Year Vehicles

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Sample Fuel Economy Labels for 2008 and Later Model Year Vehicles IV Appendix IV to Part 600 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) ENERGY POLICY FUEL ECONOMY AND CARBON-RELATED EXHAUST EMISSIONS OF MOTOR VEHICLES Pt. 600, App. IV Appendix IV to Part...

  19. Relativistic Modeling of Quark Stars with Tolman IV Type Potential

    CERN Document Server

    Malaver, Manuel

    2015-01-01

    In this paper, we studied the behavior of relativistic objects with anisotropic matter distribution considering Tolman IV form for the gravitational potential Z. The equation of state presents a quadratic relation between the energy density and the radial pressure. New exact solutions of the Einstein-Maxwell system are generated. A physical analysis of electromagnetic field indicates that is regular in the origin and well behaved. We show as the presence of an electrical field modifies the energy density, the radial pressure and the mass of the stellar object and generates a singular charge density.

  20. Accident prediction model for public highway-rail grade crossings.

    Science.gov (United States)

    Lu, Pan; Tolliver, Denver

    2016-05-01

    Considerable research has focused on roadway accident frequency analysis, but relatively little research has examined safety evaluation at highway-rail grade crossings. Highway-rail grade crossings are critical spatial locations of utmost importance for transportation safety because traffic crashes at highway-rail grade crossings are often catastrophic with serious consequences. The Poisson regression model has been employed to analyze vehicle accident frequency as a good starting point for many years. The most commonly applied variations of Poisson including negative binomial, and zero-inflated Poisson. These models are used to deal with common crash data issues such as over-dispersion (sample variance is larger than the sample mean) and preponderance of zeros (low sample mean and small sample size). On rare occasions traffic crash data have been shown to be under-dispersed (sample variance is smaller than the sample mean) and traditional distributions such as Poisson or negative binomial cannot handle under-dispersion well. The objective of this study is to investigate and compare various alternate highway-rail grade crossing accident frequency models that can handle the under-dispersion issue. The contributions of the paper are two-fold: (1) application of probability models to deal with under-dispersion issues and (2) obtain insights regarding to vehicle crashes at public highway-rail grade crossings.

  1. Podiform chromite deposits--database and grade and tonnage models

    Science.gov (United States)

    Mosier, Dan L.; Singer, Donald A.; Moring, Barry C.; Galloway, John P.

    2012-01-01

    Chromite ((Mg, Fe++)(Cr, Al, Fe+++)2O4) is the only source for the metallic element chromium, which is used in the metallurgical, chemical, and refractory industries. Podiform chromite deposits are small magmatic chromite bodies formed in the ultramafic section of an ophiolite complex in the oceanic crust. These deposits have been found in midoceanic ridge, off-ridge, and suprasubduction tectonic settings. Most podiform chromite deposits are found in dunite or peridotite near the contact of the cumulate and tectonite zones in ophiolites. We have identified 1,124 individual podiform chromite deposits, based on a 100-meter spatial rule, and have compiled them in a database. Of these, 619 deposits have been used to create three new grade and tonnage models for podiform chromite deposits. The major podiform chromite model has a median tonnage of 11,000 metric tons and a mean grade of 45 percent Cr2O3. The minor podiform chromite model has a median tonnage of 100 metric tons and a mean grade of 43 percent Cr2O3. The banded podiform chromite model has a median tonnage of 650 metric tons and a mean grade of 42 percent Cr2O3. Observed frequency distributions are also given for grades of rhodium, iridium, ruthenium, palladium, and platinum. In resource assessment applications, both major and minor podiform chromite models may be used for any ophiolite complex regardless of its tectonic setting or ophiolite zone. Expected sizes of undiscovered podiform chromite deposits, with respect to degree of deformation or ore-forming process, may determine which model is appropriate. The banded podiform chromite model may be applicable for ophiolites in both suprasubduction and midoceanic ridge settings.

  2. Computerized Classification Testing under the Generalized Graded Unfolding Model

    Science.gov (United States)

    Wang, Wen-Chung; Liu, Chen-Wei

    2011-01-01

    The generalized graded unfolding model (GGUM) has been recently developed to describe item responses to Likert items (agree-disagree) in attitude measurement. In this study, the authors (a) developed two item selection methods in computerized classification testing under the GGUM, the current estimate/ability confidence interval method and the cut…

  3. Bayesian Estimation of Multi-Unidimensional Graded Response IRT Models

    Science.gov (United States)

    Kuo, Tzu-Chun

    2015-01-01

    Item response theory (IRT) has gained an increasing popularity in large-scale educational and psychological testing situations because of its theoretical advantages over classical test theory. Unidimensional graded response models (GRMs) are useful when polytomous response items are designed to measure a unified latent trait. They are limited in…

  4. Cesar Chavez--Grade Seven Model Curriculum and Resources.

    Science.gov (United States)

    California State Dept. of Education, Sacramento.

    In this California state curriculum model for grade 7, "World History and Geography: Medieval Society," students study the life, work, and philosophy of Cesar Chavez. They learn about the ideas and philosophies that have withstood the test of time and emerged in Chavez's work and actions. Students examine Chavez's ancestral heritage link to early…

  5. Cesar Chavez--Grade Six Model Curriculum and Resources.

    Science.gov (United States)

    California State Dept. of Education, Sacramento.

    In this California state curriculum model for grade 6, "World History and Geography: Ancient Civilization," students learn that religious ideas have inspired and influenced the lives and actions of men and women, including Cesar Chavez. They see how his unselfishness, compassion for others, tolerance, and nonviolence have roots reaching back…

  6. Grade and Tonnage Model of Contact Metasomatic Copper Deposit in China

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Grade-tonnage model is one of the research frontiers of systematical exploration theory. Based on the “Reserve Database of Mineral Resources in China (1997)”, this paper establishes the geological model, grade model, tonnage model, grade-tonnage model and tonnage-sequence model of contact metasomatic copper deposits in China. The mathematical properties of these models are described in detail.

  7. The relationship between the Five-Factor Model and latent DSM-IV personality disorder dimensions

    OpenAIRE

    Nestadt, Gerald; Costa, Paul T.; Hsu, Fang-Chi; Samuels, Jack; Bienvenu, O Joseph; Eaton, William W.

    2007-01-01

    This study compared the latent structure of the DSM-IV personality disorders to the Five-Factor Model (FFM) of general personality dimensions. The subjects in the study were 742 community-residing individuals who participated in the Hopkins Epidemiology of Personality Disorder Study. DSM-IV personality disorder traits were assessed by psychologists using the International Personality Disorder Examination, and personality disorder dimensions were derived previously using dichotomous factor ana...

  8. The relationship between the Five-Factor Model and latent DSM-IV personality disorder dimensions

    OpenAIRE

    Nestadt, Gerald; Costa, Paul T.; Hsu, Fang-Chi; Samuels, Jack; Bienvenu, O. Joseph; Eaton, William W.

    2007-01-01

    This study compared the latent structure of the DSM-IV personality disorders to the Five-Factor Model (FFM) of general personality dimensions. The subjects in the study were 742 community-residing individuals who participated in the Hopkins Epidemiology of Personality Disorder Study. DSM-IV personality disorder traits were assessed by psychologists using the International Personality Disorder Examination, and personality disorder dimensions were derived previously using dichotomous factor ana...

  9. A theoretical retention model for unsaturated uniform and graded soils

    Directory of Open Access Journals (Sweden)

    Monnet Jacques

    2016-01-01

    Full Text Available Modelling the relation between the degree of saturation and the suction (ie retention curve is an important challenge for geotechnical engineering. It has a huge influence on the behavior of large soil constructions as levees, embankments, road earthworks. We present here a theoretical model of retention curve which considers physical relations of unsaturated soils. With this approach, there is no need to assume particular shapes of the retention curves, which are a consequence of the physical assumptions. The present study is focused on a theoretical model based on elastic spherical particle arrangement. As a first step a uniform model is presented with a single diameter of soil particle. A second step extends the use of the model to graded soils. The model uses only 5 physical parameters. It is compared with the experimental retention curve of two different samples of glass uniform particles and two different graded soils, a graded glass sample and the Livet-Gavet loam. It shows its ability to model the experimental curves and a better agreement than the former theory of Brooks and Corey (1966. This current publication is funded by the French National Project «Terredurable» (ANR 2011,.

  10. Endogeneity in Panel Data Models with Time-Varying and Time-Fixed Regressors: To IV or not IV?

    DEFF Research Database (Denmark)

    Mitze, Timo

    We analyse the problem of parameter inconsistency in panel data econometrics due to the correlation of exogenous variables with the error term.A common solution in this setting is to use Instrumental-Variable (IV) estimation in the spirit of Hausman-Taylor (1981). However, some potential shortcom......We analyse the problem of parameter inconsistency in panel data econometrics due to the correlation of exogenous variables with the error term.A common solution in this setting is to use Instrumental-Variable (IV) estimation in the spirit of Hausman-Taylor (1981). However, some potential...... shortcomings of the latter approach recently gave rise to the use of non-IV two-step estimators. Given their growing number of empirical applications, we aim to systematically compare the performance of IV and non-IV approaches in the presence of time-fixed variables and right hand side endogeneity using Monte...

  11. [The application of pulsed magnetic stimulation in the rehabilitation of the children operated for the treatment of grade III-IV scoliosis].

    Science.gov (United States)

    Khan, M A; Podgornaia, O V; Tarasov, N I; Bitokova, L L; Vakhova, E L; Kuiantseva, L V

    2013-01-01

    In the present paper, we for the first time provide a rationale for the application of a new physical factor, pulsed magnetic stimulation, in pediatric practice. Our observations have demonstrated positive dynanfics of the parameters characterizing the functional state of the neuro-muscular apparatus and equalization of the amplitude of M-response as appears from the results of electromyographic studies. The data obtained by electrocardiography and estimation of the external respiratory function give evidence of favourable dynamics of the cardio-respiratory system. The results of the study have been used to substantiate the application of a new method of pulsed magnetic stimulation in pediatric medicine at the early stages of rehabilitation of the children following surgical treatment of grade Ill-IV scoliosis.

  12. Models of cuspy triaxial stellar systems. IV: Rotating systems

    CERN Document Server

    Carpintero, D D

    2016-01-01

    We built two self-consistent models of triaxial, cuspy, rotating stellar systems adding rotation to non-rotating models presented in previous papers of this series. The final angular velocity of the material is not constant and varies with the distance to the center and with the height over the equator of the systems, but the figure rotation is very uniform in both cases. Even though the addition of rotation to the models modifies their original semiaxes ratios, the final rotating models are considerably flattened and triaxial. An analysis of the orbital content of the models shows that about two thirds of their orbits are chaotic yet the models are very stable over intervals of the order of one Hubble time. The bulk of regular orbits are short axis tubes, while long axis tubes are replaced by tubes whose axes lie on the short-long axes plane, but do not coincide with the major axis. Other types of regular orbits that do not appear in non-rotating systems, like horseshoes and orbits that cross themselves, are...

  13. Cloudy bag model IV. Pionic corrections to the nucleon properties

    Energy Technology Data Exchange (ETDEWEB)

    Theberge, S. (British Columbia Univ., Vancouver (Canada). Dept. of Physics); Miller, G.A. (Washington Univ., Seattle (USA). Dept. of Physics); Thomas, A.W. (British Columbia Univ., Vancouver (Canada). TRIUMF Facility)

    1982-01-01

    A detailed formulation of the Hamiltonian formalism, together with a consistent renormalization procedure, is described for the cloudy bag model. The electromagnetic properties of the nucleon are calculated with center-of-mass corrections included. Good agreement with the experimental results is obtained for bag radii ranging from 0.8 to 1.0 fm.

  14. 3D continuum phonon model for group-IV 2D materials

    DEFF Research Database (Denmark)

    Willatzen, Morten; Lew Yan Voon, Lok C.; Gandi, Appala Naidu

    2017-01-01

    . In this paper, we use the model to not only compare the phonon spectra among the group-IV materials but also to study whether these phonons differ from those of a compound material such as molybdenum disulfide. The origin of quadratic modes is clarified. Mode coupling for both graphene and silicene is obtained......, contrary to previous works. Our model allows us to predict the existence of confined optical phonon modes for the group-IV materials but not for molybdenum disulfide. A comparison of the long-wavelength modes to density-functional results is included....

  15. Models of neural networks IV early vision and attention

    CERN Document Server

    Cowan, Jack; Domany, Eytan

    2002-01-01

    Close this book for a moment and look around you. You scan the scene by directing your attention, and gaze, at certain specific objects. Despite the background, you discern them. The process is partially intentional and partially preattentive. How all this can be done is described in the fourth volume of Models of Neural Networks devoted to Early Vision and Atten­ tion that you are holding in your hands. Early vision comprises the first stages of visual information processing. It is as such a scientific challenge whose clarification calls for a penetrating review. Here you see the result. The Heraeus Foundation (Hanau) is to be thanked for its support during the initial phase of this project. John Hertz, who has extensive experience in both computational and ex­ perimental neuroscience, provides in "Neurons, Networks, and Cognition" to neural modeling. John Van Opstal explains in a theoretical introduction "The Gaze Control System" how the eye's gaze control is performed and presents a novel theoretical des...

  16. Tidal Downsizing model - IV. Destructive feedback in planets

    Science.gov (United States)

    Nayakshin, Sergei

    2016-09-01

    The role of negative feedback from a massive solid core on its massive gas envelope in the Tidal Downsizing scenario of planet formation is investigated via one-dimensional planet evolution models followed by population synthesis calculations. It is shown that cores more massive than ˜10 M⊕ release enough energy to reverse contraction of their parent gas envelopes, culminating in their destruction. This process may help to explain why observed gas giant planets are so rare, why massive cores are so ubiquitous, and why there is a sharp rollover in the core mass function above ˜20 M⊕. Additionally, the short time-scales with which these massive cores are assembled in TD may help explain formation route of Uranus, Neptune and the suspected HL Tau planets. Given the negative role of cores in assembly of gas giants in the model, an antimony is found between massive cores and gas giants: cores in survived gas giant planets are on average less massive than cores free of massive envelopes. In rare circumstances when core feedback self-regulates, extremely metal-rich gas giants, such as CoRoT-20b, a gas giant made of heavy elements by up to ˜50 per cent, can be made.

  17. Comparing personality disorder models: cross-method assessment of the FFM and DSM-IV-TR.

    Science.gov (United States)

    Samuel, Douglas B; Widiger, Thomas W

    2010-12-01

    The current edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR; American Psychiatric Association, 2000) defines personality disorders as categorical entities that are distinct from each other and from normal personality traits. However, many scientists now believe that personality disorders are best conceptualized using a dimensional model of traits that span normal and abnormal personality, such as the Five-Factor Model (FFM). However, if the FFM or any dimensional model is to be considered as a credible alternative to the current model, it must first demonstrate an increment in the validity of the assessment offered within a clinical setting. Thus, the current study extended previous research by comparing the convergent and discriminant validity of the current DSM-IV-TR model to the FFM across four assessment methodologies. Eighty-eight individuals receiving ongoing psychotherapy were assessed for the FFM and the DSM-IV-TR personality disorders using self-report, informant report, structured interview, and therapist ratings. The results indicated that the FFM had an appreciable advantage over the DSM-IV-TR in terms of discriminant validity and, at the domain level, convergent validity. Implications of the findings and directions for future research are discussed.

  18. Antiproliferative Pt(IV) complexes: synthesis, biological activity, and quantitative structure-activity relationship modeling.

    Science.gov (United States)

    Gramatica, Paola; Papa, Ester; Luini, Mara; Monti, Elena; Gariboldi, Marzia B; Ravera, Mauro; Gabano, Elisabetta; Gaviglio, Luca; Osella, Domenico

    2010-09-01

    Several Pt(IV) complexes of the general formula [Pt(L)2(L')2(L'')2] [axial ligands L are Cl-, RCOO-, or OH-; equatorial ligands L' are two am(m)ine or one diamine; and equatorial ligands L'' are Cl- or glycolato] were rationally designed and synthesized in the attempt to develop a predictive quantitative structure-activity relationship (QSAR) model. Numerous theoretical molecular descriptors were used alongside physicochemical data (i.e., reduction peak potential, Ep, and partition coefficient, log Po/w) to obtain a validated QSAR between in vitro cytotoxicity (half maximal inhibitory concentrations, IC50, on A2780 ovarian and HCT116 colon carcinoma cell lines) and some features of Pt(IV) complexes. In the resulting best models, a lipophilic descriptor (log Po/w or the number of secondary sp3 carbon atoms) plus an electronic descriptor (Ep, the number of oxygen atoms, or the topological polar surface area expressed as the N,O polar contribution) is necessary for modeling, supporting the general finding that the biological behavior of Pt(IV) complexes can be rationalized on the basis of their cellular uptake, the Pt(IV)-->Pt(II) reduction, and the structure of the corresponding Pt(II) metabolites. Novel compounds were synthesized on the basis of their predicted cytotoxicity in the preliminary QSAR model, and were experimentally tested. A final QSAR model, based solely on theoretical molecular descriptors to ensure its general applicability, is proposed.

  19. Testing Structural Models of DSM-IV Symptoms of Common Forms of Child and Adolescent Psychopathology

    Science.gov (United States)

    Lahey, Benjamin B.; Rathouz, Paul J.; Van Hulle, Carol; Urbano, Richard C.; Krueger, Robert F.; Applegate, Brooks; Garriock, Holly A.; Chapman, Derek A.; Waldman, Irwin D.

    2008-01-01

    Confirmatory factor analyses were conducted of "Diagnostic and Statistical Manual of Mental Disorders", Fourth Edition (DSM-IV) symptoms of common mental disorders derived from structured interviews of a representative sample of 4,049 twin children and adolescents and their adult caretakers. A dimensional model based on the assignment of symptoms…

  20. Comparing factor analytic models of the DSM-IV personality disorders.

    Science.gov (United States)

    Huprich, Steven K; Schmitt, Thomas A; Richard, David C S; Chelminski, Iwona; Zimmerman, Mark A

    2010-01-01

    There is little agreement about the latent factor structure of the Diagnostic and Statistical Manual of Mental Disorders (DSM) personality disorders (PDs). Factor analytic studies over the past 2 decades have yielded different results, in part reflecting differences in factor analytic technique, the measure used to assess the PDs, and the changing DSM criteria. In this study, we explore the latent factor structure of the DSM (4th ed.; IV) PDs in a sample of 1200 psychiatric outpatients evaluated with the Structured Interview for DSM-IV PDs (B. Pfohl, N. Blum, & M. Zimmerman, 1997). We first evaluated 2 a priori models of the PDs with confirmatory factor analysis (CFA), reflecting their inherent organization in the DSM-IV: a 3-factor model and a 10-factor model. Fit statistics did not suggest that these models yielded an adequate fit. We then evaluated the latent structure with exploratory factor analysis (EFA). Multiple solutions produced more statistically and theoretically reasonable results, as well as providing clinically useful findings. On the basis of fit statistics and theory, 3 models were evaluated further--the 4-, 5-, and 10-factor models. The 10-factor model, which did not resemble the 10-factor model of the CFA, was determined to be the strongest of all 3 models. Future research should use contemporary methods of evaluating factor analytic results in order to more thoroughly compare various factor solutions.

  1. Generalization of Weber's adiabatic bond charge model to amorphous group IV semiconductors

    Science.gov (United States)

    Winer, K.; Wooten, F.

    1984-11-01

    The generalization of Weber's adiabatic bond charge model to amorphous group IV semiconductors is described. Methods of relaxing the coordinates to their equilibrium configuration and of calculating the dynamical matrix for the phonon spectra are given. Particular emphasis is given to the optimization of the Coulomb subroutines required in this model. Estimates of computation time are included for the calculation of equilibrium configuration on a Cray computer.

  2. Modeling individual subtests of the WAIS IV with multiple latent factors.

    Directory of Open Access Journals (Sweden)

    Dennis J McFarland

    Full Text Available Performance on a cognitive test can be viewed either as measuring a unitary function or as reflecting the operation of multiple factors. Individual subtests in batteries designed to measure human abilities are commonly modeled as a single latent factor. Several latent factors are then used to model groups of subtests. However these latent factors are not independent as they are related through hierarchical or oblique structures. As a result, the simple structure of subtest performance results in complex latent factors. The present study used structural equation modeling to evaluate several multidimensional models of the Wechsler Adult Intelligence Scales-fourth edition (WAIS-IV subtests. Multidimensional models of subtest performance provided better model fit as compared to several previously proposed one dimensional models. These multidimensional models also generalized well to new samples of populations differing in age from that used to estimate the model parameters. Overall these results show that models that describe subtests as multidimensional functions of uncorrelated factors provided a better fit to the WAIS-IV correlations than models that describe subtests as one dimensional functions of correlated factors. There appears to be a trade-off in modeling subtests as one dimensional and modeling with homogeneous latent traits. More consideration should be given to models that include multiple uncorrelated latent factors as determinants of the performance on a given subtest. These results support the view that performance on any given cognitive test is potentially the result of multiple factors. Simple structure may be too simple.

  3. Modeling individual subtests of the WAIS IV with multiple latent factors.

    Science.gov (United States)

    McFarland, Dennis J

    2013-01-01

    Performance on a cognitive test can be viewed either as measuring a unitary function or as reflecting the operation of multiple factors. Individual subtests in batteries designed to measure human abilities are commonly modeled as a single latent factor. Several latent factors are then used to model groups of subtests. However these latent factors are not independent as they are related through hierarchical or oblique structures. As a result, the simple structure of subtest performance results in complex latent factors. The present study used structural equation modeling to evaluate several multidimensional models of the Wechsler Adult Intelligence Scales-fourth edition (WAIS-IV) subtests. Multidimensional models of subtest performance provided better model fit as compared to several previously proposed one dimensional models. These multidimensional models also generalized well to new samples of populations differing in age from that used to estimate the model parameters. Overall these results show that models that describe subtests as multidimensional functions of uncorrelated factors provided a better fit to the WAIS-IV correlations than models that describe subtests as one dimensional functions of correlated factors. There appears to be a trade-off in modeling subtests as one dimensional and modeling with homogeneous latent traits. More consideration should be given to models that include multiple uncorrelated latent factors as determinants of the performance on a given subtest. These results support the view that performance on any given cognitive test is potentially the result of multiple factors. Simple structure may be too simple.

  4. Transferable tight binding model for strained group IV and III-V heterostructures

    Science.gov (United States)

    Tan, Yaohua; Povolotskyi, Micheal; Kubis, Tillmann; Boykin, Timothy; Klimeck, Gerhard

    Modern semiconductor devices have reached critical device dimensions in the range of several nanometers. For reliable prediction of device performance, it is critical to have a numerical efficient model that are transferable to material interfaces. In this work, we present an empirical tight binding (ETB) model with transferable parameters for strained IV and III-V group semiconductors. The ETB model is numerically highly efficient as it make use of an orthogonal sp3d5s* basis set with nearest neighbor inter-atomic interactions. The ETB parameters are generated from HSE06 hybrid functional calculations. Band structures of strained group IV and III-V materials by ETB model are in good agreement with corresponding HSE06 calculations. Furthermore, the ETB model is applied to strained superlattices which consist of group IV and III-V elements. The ETB model turns out to be transferable to nano-scale hetero-structure. The ETB band structures agree with the corresponding HSE06 results in the whole Brillouin zone. The ETB band gaps of superlattices with common cations or common anions have discrepancies within 0.05eV.

  5. Successful pregnancy outcome in grade IV lupus nephritis and secondary antiphospholipid antibody syndrome with recurrent pregnancy failures - challenging achievement of motherhood

    Directory of Open Access Journals (Sweden)

    Kaliki Hymavathi Reddy

    2016-12-01

    Full Text Available Systemic lupus erythematosus (SLE is a chronic multisystem autoimmune disease that occurs predominantly in women of childbearing age. The risk of complications and adverse fetal outcomes in pregnant women with lupus is high viz., increased risks of preterm birth, hypertensive diseases of pregnancy and lupus flares both during pregnancy and in the postpartum period. An additional association with Antiphospholipid antibody (APLA syndrome is expected to multiply the pregnancy complications. Though improved understanding of the disease nature and greater number of therapeutic options in the treatment of SLE, made the medical community regard these patients with less trepidation, the risk of significant morbidity to both the mother and the fetus still exist. We report an interesting case of grade IV Lupus nephritis (LN with secondary APLA syndrome and h/o recurrent pregnancy failures for twenty times but had a successful pregnancy and delivery in the 21st attempt though pregnancy was absolutely contraindicated in view of her medical illness. Many complications were encountered during her pregnancy which could be successfully tackled and a live male baby was delivered by Caesarean section.

  6. Bifactor model of WISC-IV: Applicability and measurement invariance in low and normal IQ groups.

    Science.gov (United States)

    Gomez, Rapson; Vance, Alasdair; Watson, Shaun

    2017-07-01

    This study examined the applicability and measurement invariance of the bifactor model of the 10 Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV) core subtests in groups of children and adolescents (age range from 6 to 16 years) with low (IQ ≤79; N = 229; % male = 75.9) and normal (IQ ≥80; N = 816; % male = 75.0) IQ scores. Results supported this model in both groups, and there was good support for measurement invariance for this model across these groups. For all participants together, the omega hierarchical and explained common variance (ECV) values were high for the general factor and low to negligible for the specific factors. Together, the findings favor the use of the Full Scale IQ (FSIQ) scores of the WISC-IV, but not the subscale index scores. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  7. 3D continuum phonon model for group-IV 2D materials

    KAUST Repository

    Willatzen, Morten

    2017-06-30

    A general three-dimensional continuum model of phonons in two-dimensional materials is developed. Our first-principles derivation includes full consideration of the lattice anisotropy and flexural modes perpendicular to the layers and can thus be applied to any two-dimensional material. In this paper, we use the model to not only compare the phonon spectra among the group-IV materials but also to study whether these phonons differ from those of a compound material such as molybdenum disulfide. The origin of quadratic modes is clarified. Mode coupling for both graphene and silicene is obtained, contrary to previous works. Our model allows us to predict the existence of confined optical phonon modes for the group-IV materials but not for molybdenum disulfide. A comparison of the long-wavelength modes to density-functional results is included.

  8. Statistical Models of Fracture Relevant to Nuclear-Grade Graphite: Review and Recommendations

    Science.gov (United States)

    Nemeth, Noel N.; Bratton, Robert L.

    2011-01-01

    The nuclear-grade (low-impurity) graphite needed for the fuel element and moderator material for next-generation (Gen IV) reactors displays large scatter in strength and a nonlinear stress-strain response from damage accumulation. This response can be characterized as quasi-brittle. In this expanded review, relevant statistical failure models for various brittle and quasi-brittle material systems are discussed with regard to strength distribution, size effect, multiaxial strength, and damage accumulation. This includes descriptions of the Weibull, Batdorf, and Burchell models as well as models that describe the strength response of composite materials, which involves distributed damage. Results from lattice simulations are included for a physics-based description of material breakdown. Consideration is given to the predicted transition between brittle and quasi-brittle damage behavior versus the density of damage (level of disorder) within the material system. The literature indicates that weakest-link-based failure modeling approaches appear to be reasonably robust in that they can be applied to materials that display distributed damage, provided that the level of disorder in the material is not too large. The Weibull distribution is argued to be the most appropriate statistical distribution to model the stochastic-strength response of graphite.

  9. Confirmatory Factor Analysis of WAIS-IV in a Clinical Sample: Examining a Bi-Factor Model

    Directory of Open Access Journals (Sweden)

    Rachel Collinson

    2016-12-01

    Full Text Available There have been a number of studies that have examined the factor structure of the Wechsler Adult Intelligence Scale IV (WAIS-IV using the standardization sample. In this study, we investigate its factor structure on a clinical neuropsychology sample of mixed aetiology. Correlated factor, higher-order and bi-factor models are all tested. Overall, the results suggest that the WAIS-IV will be suitable for use with this population.

  10. Confirmatory Factor Analysis of WAIS-IV in a Clinical Sample: Examining a Bi-Factor Model

    OpenAIRE

    Rachel Collinson; Stephen Evans; Miranda Wheeler; Don Brechin; Jenna Moffitt; Geoff Hill; Steven Muncer

    2016-01-01

    There have been a number of studies that have examined the factor structure of the Wechsler Adult Intelligence Scale IV (WAIS-IV) using the standardization sample. In this study, we investigate its factor structure on a clinical neuropsychology sample of mixed aetiology. Correlated factor, higher-order and bi-factor models are all tested. Overall, the results suggest that the WAIS-IV will be suitable for use with this population.

  11. A Qualitative Analysis of The Bianchi Type IV Viscous Fluid Model

    CERN Document Server

    Kohli, Ikjyot Singh

    2012-01-01

    We are interested in formulating a viscous model of the universe based on The Bianchi Type IV algebra. We first begin by considering a congruence of fluid lines in spacetime, upon which, analyzing their propagation behaviour, we derive the famous Raychaudhuri equation, but, in the context of viscous fluids. We will then go through in great detail the topological and algebraic structure of a Bianchi Type IV algebra, by which we will derive the corresponding structure and constraint equations. From this, we will look at The Einstein field equations in the context of orthonormal frames, and derive the resulting dynamical equations: The Raychaudhuri Equation, generalized Friedmann equation, shear propagation equations, and a set of non-trivial constraint equations. We show that for cases in which the bulk viscous pressure is significantly larger than the shear viscosity, this cosmological model isotropizes asymptotically.

  12. Multiscale Modeling of the Deformation of Advanced Ferritic Steels for Generation IV Nuclear Energy

    Energy Technology Data Exchange (ETDEWEB)

    Nasr M. Ghoniem; Nick Kioussis

    2009-04-18

    The objective of this project is to use the multi-scale modeling of materials (MMM) approach to develop an improved understanding of the effects of neutron irradiation on the mechanical properties of high-temperature structural materials that are being developed or proposed for Gen IV applications. In particular, the research focuses on advanced ferritic/ martensitic steels to enable operation up to 650-700°C, compared to the current 550°C limit on high-temperature steels.

  13. The i-V curve characteristics of burner-stabilized premixed flames: detailed and reduced models

    KAUST Repository

    Han, Jie

    2016-07-17

    The i-V curve describes the current drawn from a flame as a function of the voltage difference applied across the reaction zone. Since combustion diagnostics and flame control strategies based on electric fields depend on the amount of current drawn from flames, there is significant interest in modeling and understanding i-V curves. We implement and apply a detailed model for the simulation of the production and transport of ions and electrons in one-dimensional premixed flames. An analytical reduced model is developed based on the detailed one, and analytical expressions are used to gain insight into the characteristics of the i-Vcurve for various flame configurations. In order for the reduced model to capture the spatial distribution of the electric field accurately, the concept of a dead zone region, where voltage is constant, is introduced, and a suitable closure for the spatial extent of the dead zone is proposed and validated. The results from the reduced modeling framework are found to be in good agreement with those from the detailed simulations. The saturation voltage is found to depend significantly on the flame location relative to the electrodes, and on the sign of the voltage difference applied. Furthermore, at sub-saturation conditions, the current is shown to increase linearly or quadratically with the applied voltage, depending on the flame location. These limiting behaviors exhibited by the reduced model elucidate the features of i-V curves observed experimentally. The reduced model relies on the existence of a thin layer where charges are produced, corresponding to the reaction zone of a flame. Consequently, the analytical model we propose is not limited to the study of premixed flames, and may be applied easily to others configurations, e.g.~nonpremixed counterflow flames.

  14. Modelling cell polarization driven by synthetic spatially graded Rac activation.

    Directory of Open Access Journals (Sweden)

    William R Holmes

    Full Text Available The small GTPase Rac is known to be an important regulator of cell polarization, cytoskeletal reorganization, and motility of mammalian cells. In recent microfluidic experiments, HeLa cells endowed with appropriate constructs were subjected to gradients of the small molecule rapamycin leading to synthetic membrane recruitment of a Rac activator and direct graded activation of membrane-associated Rac. Rac activation could thus be triggered independent of upstream signaling mechanisms otherwise responsible for transducing activating gradient signals. The response of the cells to such stimulation depended on exceeding a threshold of activated Rac. Here we develop a minimal reaction-diffusion model for the GTPase network alone and for GTPase-phosphoinositide crosstalk that is consistent with experimental observations for the polarization of the cells. The modeling suggests that mutual inhibition is a more likely mode of cell polarization than positive feedback of Rac onto its own activation. We use a new analytical tool, Local Perturbation Analysis, to approximate the partial differential equations by ordinary differential equations for local and global variables. This method helps to analyze the parameter space and behaviour of the proposed models. The models and experiments suggest that (1 spatially uniform stimulation serves to sensitize a cell to applied gradients. (2 Feedback between phosphoinositides and Rho GTPases sensitizes a cell. (3 Cell lengthening/flattening accompanying polarization can increase the sensitivity of a cell and stabilize an otherwise unstable polarization.

  15. Modeling the States of Matter in a First-Grade Classroom

    Science.gov (United States)

    Lott, Kimberly; Wallin, Lynn

    2012-01-01

    Scientific modeling along with hands-on inquiry can lead to a deeper understanding of scientific concepts among students in upper elementary grades. Even though scientific modeling involves abstract-thinking processes, can students in younger elementary grades successfully participate in scientific modeling? Scientific modeling, like all other…

  16. A cardiovascular mathematical model of graded head-up tilt.

    Directory of Open Access Journals (Sweden)

    Einly Lim

    Full Text Available A lumped parameter model of the cardiovascular system has been developed and optimized using experimental data obtained from 13 healthy subjects during graded head-up tilt (HUT from the supine position to [Formula: see text]. The model includes descriptions of the left and right heart, direct ventricular interaction through the septum and pericardium, the systemic and pulmonary circulations, nonlinear pressure volume relationship of the lower body compartment, arterial and cardiopulmonary baroreceptors, as well as autoregulatory mechanisms. A number of important features, including the separate effects of arterial and cardiopulmonary baroreflexes, and autoregulation in the lower body, as well as diastolic ventricular interaction through the pericardium have been included and tested for their significance. Furthermore, the individual effect of parameter associated with heart failure, including LV and RV contractility, baseline systemic vascular resistance, pulmonary vascular resistance, total blood volume, LV diastolic stiffness and reflex gain on HUT response have also been investigated. Our fitted model compares favorably with our experimental measurements and published literature at a range of tilt angles, in terms of both global and regional hemodynamic variables. Compared to the normal condition, a simulated congestive heart failure condition produced a blunted response to HUT with regards to the percentage changes in cardiac output, stroke volume, end diastolic volume and effector response (i.e., heart contractility, venous unstressed volume, systemic vascular resistance and heart rate with progressive tilting.

  17. Temporal Lobe Reactions After Carbon Ion Radiation Therapy: Comparison of Relative Biological Effectiveness–Weighted Tolerance Doses Predicted by Local Effect Models I and IV

    Energy Technology Data Exchange (ETDEWEB)

    Gillmann, Clarissa, E-mail: clarissa.gillmann@med.uni-heidelberg.de [Department of Radiation Oncology and Radiation Therapy, Heidelberg University Hospital, Heidelberg (Germany); Jäkel, Oliver [Department of Radiation Oncology and Radiation Therapy, Heidelberg University Hospital, Heidelberg (Germany); Heidelberg Ion Beam Therapy Center (HIT), Heidelberg (Germany); Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg (Germany); Schlampp, Ingmar [Department of Radiation Oncology and Radiation Therapy, Heidelberg University Hospital, Heidelberg (Germany); Karger, Christian P. [Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg (Germany)

    2014-04-01

    Purpose: To compare the relative biological effectiveness (RBE)–weighted tolerance doses for temporal lobe reactions after carbon ion radiation therapy using 2 different versions of the local effect model (LEM I vs LEM IV) for the same patient collective under identical conditions. Methods and Materials: In a previous study, 59 patients were investigated, of whom 10 experienced temporal lobe reactions (TLR) after carbon ion radiation therapy for low-grade skull-base chordoma and chondrosarcoma at Helmholtzzentrum für Schwerionenforschung (GSI) in Darmstadt, Germany in 2002 and 2003. TLR were detected as visible contrast enhancements on T1-weighted MRI images within a median follow-up time of 2.5 years. Although the derived RBE-weighted temporal lobe doses were based on the clinically applied LEM I, we have now recalculated the RBE-weighted dose distributions using LEM IV and derived dose-response curves with Dmax,V-1 cm³ (the RBE-weighted maximum dose in the remaining temporal lobe volume, excluding the volume of 1 cm³ with the highest dose) as an independent dosimetric variable. The resulting RBE-weighted tolerance doses were compared with those of the previous study to assess the clinical impact of LEM IV relative to LEM I. Results: The dose-response curve of LEM IV is shifted toward higher values compared to that of LEM I. The RBE-weighted tolerance dose for a 5% complication probability (TD{sub 5}) increases from 68.8 ± 3.3 to 78.3 ± 4.3 Gy (RBE) for LEM IV as compared to LEM I. Conclusions: LEM IV predicts a clinically significant increase of the RBE-weighted tolerance doses for the temporal lobe as compared to the currently applied LEM I. The limited available photon data do not allow a final conclusion as to whether RBE predictions of LEM I or LEM IV better fit better clinical experience in photon therapy. The decision about a future clinical application of LEM IV therefore requires additional analysis of temporal lobe reactions in a

  18. Behavior of platinum(iv) complexes in models of tumor hypoxia: cytotoxicity, compound distribution and accumulation.

    Science.gov (United States)

    Schreiber-Brynzak, Ekaterina; Pichler, Verena; Heffeter, Petra; Hanson, Buck; Theiner, Sarah; Lichtscheidl-Schultz, Irene; Kornauth, Christoph; Bamonti, Luca; Dhery, Vineet; Groza, Diana; Berry, David; Berger, Walter; Galanski, Markus; Jakupec, Michael A; Keppler, Bernhard K

    2016-04-01

    Hypoxia in solid tumors remains a challenge for conventional cancer therapeutics. As a source for resistance, metastasis development and drug bioprocessing, it influences treatment results and disease outcome. Bioreductive platinum(iv) prodrugs might be advantageous over conventional metal-based therapeutics, as biotransformation in a reductive milieu, such as under hypoxia, is required for drug activation. This study deals with a two-step screening of experimental platinum(iv) prodrugs with different rates of reduction and lipophilicity with the aim of identifying the most appropriate compounds for further investigations. In the first step, the cytotoxicity of all compounds was compared in hypoxic multicellular spheroids and monolayer culture using a set of cancer cell lines with different sensitivities to platinum(ii) compounds. Secondly, two selected compounds were tested in hypoxic xenografts in SCID mouse models in comparison to satraplatin, and, additionally, (LA)-ICP-MS-based accumulation and distribution studies were performed for these compounds in hypoxic spheroids and xenografts. Our findings suggest that, while cellular uptake and cytotoxicity strongly correlate with lipophilicity, cytotoxicity under hypoxia compared to non-hypoxic conditions and antitumor activity of platinum(iv) prodrugs are dependent on their rate of reduction.

  19. Modeling selenium (IV and VI) adsorption envelopes in selected tropical soils using the constant capacitance model

    Science.gov (United States)

    The adsorption of selenium (Se) on soil is important due to the relevance of Se to environmental and health issues. The adsorption of Se(IV) and Se(VI) was evaluated on soil samples from São Paulo state, Brazil, as a function of varying pH, and the experimental data were fitted to the constant capac...

  20. A rabbit model of graded primary mechanical injury to brainstem

    Institute of Scientific and Technical Information of China (English)

    YU Yong-min; WANG Xiao-wei; XUE Hai-bin; XIA Peng; LI Hong-wei; DAI Guo-xin; JI Xiao-yuan; ZHAO Hui; YIN Zhi-yong

    2012-01-01

    Objective:To introduce a new animal model of graded mechanical primary brainstem injury (BSI).Methods:Altogether 45 rabbits were subjected to BSI by type Ⅱ biological impact machine designed by the Third Military Medical University.The animals were divided into 4 experimental groups (n=10) and 1 control group (n=5) according to different magnitudes of impact pressure imposed on the occipital nodule:Group 1,500-520 kPa; Group 2,520-540 kPa; Group 3,540-560 kPa; Group 4,560-580 kPa and Group 5,0 kPa with 20 kPa increase in each grade.The impact depth was a constant 0.5 cm.After injury,the clinical symptoms and signs as well as pathological changes were observed.Results:Rabbits in Group 1 revealed mild physiological reaction of BSI.They had localized cerebral contusion with punctate hemorrhage and subarachnoid hemorrhage (SAH) was limited to the peripheral tissues at the impact area.In Group 2,obvious physiological reaction was observed.Local pathological lesions reached the superficial layer ofbrainstem tissues; focal hemorrhage and girdleshaped SAH in basilar pon were observed under microscope.In Group 3,BSI was more severe with a long respiratory depression.Pathological lesions reached the inner portion of brainstem with massive hemorrhage and the whole brainstem was wrapped by subarachnoid hematoma.In Group 4,most rabbits died due to severe BSI.Pathological lesions deepened to the central brainstem with wide pathological change,rapture of the medulla oblongata central canal.Group 5 was the control group,with normal brainstem structure and no lesion observed.Conclusion:This model successfully simulates different levels ofbrainstem mechanical injury and clearly shows the subsequent pathological changes following injury.It takes two external parameters (impact pressure and depth) and has a similar injury mechanism to clinical accelerating BSI.Moreover it is reproducible and stable,thus being beneficial for exploring pathophysiological mechanism,diagnosis and

  1. Future Asymptotic Behaviour of Tilted Bianchi models of type IV and VIIh

    CERN Document Server

    Hervik, S; Coley, Alan A; Hervik, Sigbjorn; Hoogen, Robert van den; Coley, Alan

    2005-01-01

    Using dynamical systems theory and a detailed numerical analysis, the late-time behaviour of tilting perfect fluid Bianchi models of types IV and VII$_h$ are investigated. In particular, vacuum plane-wave spacetimes are studied and the important result that the only future attracting equilibrium points for non-inflationary fluids are the plane-wave solutions in Bianchi type VII$_h$ models is discussed. A tiny region of parameter space (the loophole) in the Bianchi type IV model is shown to contain a closed orbit which is found to act as an attractor (the Mussel attractor). From an extensive numerical analysis it is found that at late times the normalised energy-density tends to zero and the normalised variables 'freeze' into their asymptotic values. A detailed numerical analysis of the type VII$_h$ models then shows that there is an open set of parameter space in which solution curves approach a compact surface that is topologically a torus.

  2. Assessment of a model for achieving competency in administration and scoring of the WAIS-IV in postgraduate psychology students

    National Research Council Canada - National Science Library

    Rachel Margaret Roberts; Melissa eDavis

    2015-01-01

    .... Twenty three postgraduate psychology students underwent training in using the WAIS-IV according to a best-practice teaching model that involved didactic teaching, independent study of the test manual...

  3. Further insights on the French WISC-IV factor structure through Bayesian structural equation modeling.

    Science.gov (United States)

    Golay, Philippe; Reverte, Isabelle; Rossier, Jérôme; Favez, Nicolas; Lecerf, Thierry

    2013-06-01

    The interpretation of the Wechsler Intelligence Scale for Children--Fourth Edition (WISC-IV) is based on a 4-factor model, which is only partially compatible with the mainstream Cattell-Horn-Carroll (CHC) model of intelligence measurement. The structure of cognitive batteries is frequently analyzed via exploratory factor analysis and/or confirmatory factor analysis. With classical confirmatory factor analysis, almost all cross-loadings between latent variables and measures are fixed to zero in order to allow the model to be identified. However, inappropriate zero cross-loadings can contribute to poor model fit, distorted factors, and biased factor correlations; most important, they do not necessarily faithfully reflect theory. To deal with these methodological and theoretical limitations, we used a new statistical approach, Bayesian structural equation modeling (BSEM), among a sample of 249 French-speaking Swiss children (8-12 years). With BSEM, zero-fixed cross-loadings between latent variables and measures are replaced by approximate zeros, based on informative, small-variance priors. Results indicated that a direct hierarchical CHC-based model with 5 factors plus a general intelligence factor better represented the structure of the WISC-IV than did the 4-factor structure and the higher order models. Because a direct hierarchical CHC model was more adequate, it was concluded that the general factor should be considered as a breadth rather than a superordinate factor. Because it was possible for us to estimate the influence of each of the latent variables on the 15 subtest scores, BSEM allowed improvement of the understanding of the structure of intelligence tests and the clinical interpretation of the subtest scores. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  4. Learning discriminative classification models for grading anal intraepithelial neoplasia

    Directory of Open Access Journals (Sweden)

    Kainz Philipp

    2016-09-01

    Full Text Available Grading intraepithelial neoplasia is crucial to derive an accurate estimate of pre-cancerous stages and is currently performed by pathologists assessing histopathological images. Inter- and intra-observer variability can significantly be reduced, when reliable, quantitative image analysis is introduced into diagnostic processes. On a challenging dataset, we evaluated the potential of learning a classifier to grade anal intraepitelial neoplasia. Support vector machines were trained on images represented by fractal and statistical features. We show that pursuing a learning-based grading strategy yields highly reliable results. Compared to existing methods, the proposed method outperformed them by a significant margin.

  5. The relationships between WAIS-IV factor index scores and educational level: A bifactor model approach.

    Science.gov (United States)

    Abad, Francisco J; Sorrel, Miguel A; Román, Francisco J; Colom, Roberto

    2016-08-01

    IQ summary scores may not involve equivalent psychological meaning for different educational levels. Ultimately, this relates to the distinction between constructs and measurements. Here, we explore this issue studying the standardization of the Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) for Spain. A representative sample of 743 individuals (374 females and 369 males) who completed the 15 subtests comprising this intelligence battery was considered. We analyzed (a) the best latent factor structure for modeling WAIS-IV subtest performance, (b) measurement invariance across educational levels, and (c) the relationships of educational level/attainment with latent factors, Full Scale IQ (FSIQ), and index factor scores. These were the main findings: (a) the bifactor model provides the best fit; (b) there is partial invariance, and therefore it is concluded that the battery is a proper measure of the constructs of interest for the educational levels analyzed (nevertheless, the relevance of g decreases at high educational levels); (c) at the latent level, g and, to a lesser extent, Verbal Comprehension and Processing Speed, are positively related to educational level/attainment; (d) despite the previous finding, we find that Verbal Comprehension and Processing Speed factor index scores have reduced incremental validity beyond FSIQ; and (e) FSIQ is a slightly biased measure of g. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  6. Statistically Modeling I-V Characteristics of CNT-FET with LASSO

    Science.gov (United States)

    Ma, Dongsheng; Ye, Zuochang; Wang, Yan

    2017-08-01

    With the advent of internet of things (IOT), the need for studying new material and devices for various applications is increasing. Traditionally we build compact models for transistors on the basis of physics. But physical models are expensive and need a very long time to adjust for non-ideal effects. As the vision for the application of many novel devices is not certain or the manufacture process is not mature, deriving generalized accurate physical models for such devices is very strenuous, whereas statistical modeling is becoming a potential method because of its data oriented property and fast implementation. In this paper, one classical statistical regression method, LASSO, is used to model the I-V characteristics of CNT-FET and a pseudo-PMOS inverter simulation based on the trained model is implemented in Cadence. The normalized relative mean square prediction error of the trained model versus experiment sample data and the simulation results show that the model is acceptable for digital circuit static simulation. And such modeling methodology can extend to general devices.

  7. Modeling the relationships between cognitive-linguistic skills and writing in Chinese among elementary grades students.

    Science.gov (United States)

    Yeung, Pui-Sze; Ho, Connie Suk-Han; Chan, David Wai-Ock; Chung, Kevin Kien-Hoa

    2013-08-01

    The present study is a four-year longitudinal study examining the important predictors of writing of 340 Chinese children in elementary grades. Children's transcription skills (handwriting skills and spelling), and syntactic skills in grade 1 were significant predictors of text writing in grade 1-4 while ideation in grade 1 only contributed to text writing in grade 2. Stroke order knowledge was shown as an important handwriting skill in Chinese reflecting the characteristics of the Chinese orthography. A model of Chinese writing in early elementary grades was proposed. In the model, orthographic knowledge, morphological awareness and handwriting skills are proposed to contribute to spelling which is correlated with text writing. Handwriting skills, ideation, and syntactic skills were found to contribute to text writing. Path analysis results suggest that the longitudinal relationship between spelling and text writing is bidirectional.

  8. A model to predict the permeation of type IV hydrogen tanks

    Energy Technology Data Exchange (ETDEWEB)

    Bayle, Julien; Perreux, Dominique; Chapelle, David; Thiebaud, Frederic [MaHyTec, Dole (France); Nardin, Philippe [Franche Comte Univ. (France)

    2010-07-01

    In the frame of the certification process of the type IV hydrogen storage tanks MaHyTec aims to manufacture, this innovative SME is developing a numerical model dedicated to the study of permeation issues. Such an approach aims at avoiding complicated, time-consuming and expensive testing. Experimental results obtained under real conditions can moreover be significantly influenced by the scattering of material properties and liner dimensions. From simple testing on small-size flat membranes, the model allows to predict the gas diffusion flow through the whole structure by means of numerous parameters. On every step, theory can be compared with the results obtained from the samples. This document presents a brief review of the mathematical theory describing gas diffusion and the different aspects of the study for better understanding the proposed approach. (orig.)

  9. Superiority of second over first generation chemotherapy in a randomized trial for stage III-IV intermediate and high-grade non-Hodgkin's lymphoma (NHL): the 1980-1985 EORTC trial. The EORTC Lymphoma Group.

    Science.gov (United States)

    Carde, P; Meerwaldt, J H; van Glabbeke, M; Somers, R; Monconduit, M; Thomas, J; de Wolf-Peeters, C; de Pauw, B; Tanguy, A; Kluin-Nelemans, J C

    1991-06-01

    A first-generation CHOP-like cyclic combination chemotherapy (CT) regimen using cyclophosphamide 600 mg/m2 IV d1, hydroxorubicin (doxorubicin) 50 mg/m2 IV d1, VM26 60 mg/m2 IV d1, and prednisone 40 mg/m2 PO d1-5 (CHVmP) was compared to a second-generation combination wherein vincristine 1.4 mg/m2 IV and bleomycin 6 mg/m2 IM/IV were added at mid-interval (d15) to the former drugs (CHVmP + VB) in the treatment of intermediate- and high-grade malignant NHL. From April 1980 to January 1986, 141 eligible patients with stage III-IV unfavorable histologies (except T lymphoblastic NHL) entered this EORTC randomized trial. In both arms adjuvant radiotherapy (30 Gy) was given in instances of bulky or residual disease. In all patient subsets the outcome favored the second-generation regimen. The difference was even greater in patients with Diffuse Large Cell Lymphoma (DLCL). At 5 years, overall survival was 53% with CHVmP + VB versus 29% (p = 0.002). The advantage was due to a higher complete remission (CR) rate (80% versus 50%, p = 0.01). Indeed, once CR was achieved the relapse-free survival (RFS) was not significantly influenced (59% versus 49%). No significant additional toxicity could be attributed to vincristine and bleomycin. This study demonstrates a clear benefit for intermediate- and high-risk malignant NHL and particularly DLCL from intercalating non-myelotoxic drugs at mid-cycle intervals, without adverse effects.

  10. Application of ANFIS for analytical modeling of tensile strength of functionally graded steels

    Directory of Open Access Journals (Sweden)

    Ali Nazari

    2012-06-01

    Full Text Available In the present study, the tensile strength of ferritic and austenitic functionally graded steels produced by electroslag remelting has been modeled. To produce functionally graded steels, two slices of plain carbon steel and austenitic stainless steels were spot welded and used as electroslag remelting electrode. Functionally graded steel containing graded layers of ferrite and austenite may be fabricated via diffusion of alloying elements during remelting stage. Vickers microhardness profile of the specimen has been obtained experimentally and modeled with adaptive network-based fuzzy inference systems (ANFIS. To build the model for graded ferritic and austenitic steels, training, testing and validation using respectively 174 and 120 experimental data were conducted. According to the input parameters, in the ANFIS model, the Vickers microhardness of each layer was predicted. A good fit equation which correlates the Vickers microhardness of each layer to its corresponding chemical composition was achieved by the optimized network for both ferritic and austenitic graded steels. Afterwards; the Vickers microhardness of each layer in functionally graded steels was related to the yield stress of the corresponding layer and by assuming Holloman relation for stress-strain curve of each layer, they were acquired. Finally, by applying the rule of mixtures, tensile strength of functionally graded steels configuration was found through a numerical method. The obtained results from the proposed model are in good agreement with those acquired from the experiments.

  11. Grade 3 Students' Mathematization through Modeling: Situation Models and Solution Models with Mutli-Digit Subtraction Problem Solving

    Science.gov (United States)

    Murata, Aki; Kattubadi, Sailaja

    2012-01-01

    In considering mathematics problem solving as a model-eliciting activity (Lesh & Doerr, 2003; Lesh & Harel, 2003; Lesh & Zawojewski, 2008), it is important to know "what" students are modeling for the problems: situations or solutions. This study investigated Grade 3 students' mathematization process by examining how they modeled different…

  12. Cohesive cracked-hinge model for simulation of fracture in one-way slabs on grade

    DEFF Research Database (Denmark)

    Skar, Asmus; Poulsen, Peter Noe; Olesen, John Forbes

    2017-01-01

    Numerical analysis of slab on grade structures subjected to mechanical loads is a complex matter often requiring computationally expensive models. In order to develop a simplified and general concept for non-linear analysis of slab on grade structures, this paper presents a cohesive cracked...

  13. Bifurcations in a Seasonally Forced Predator-Prey Model with Generalized Holling Type IV Functional Response

    Science.gov (United States)

    Ren, Jingli; Li, Xueping

    A seasonally forced predator-prey system with generalized Holling type IV functional response is considered in this paper. The influence of seasonal forcing on the system is investigated via numerical bifurcation analysis. Bifurcation diagrams for periodic solutions of periods one and two, containing bifurcation curves of codimension one and bifurcation points of codimension two, are obtained by means of a continuation technique, corresponding to different bifurcation cases of the unforced system illustrated in five bifurcation diagrams. The seasonally forced model exhibits more complex dynamics than the unforced one, such as stable and unstable periodic solutions of various periods, stable and unstable quasiperiodic solutions, and chaotic motions through torus destruction or cascade of period doublings. Finally, some phase portraits and corresponding Poincaré map portraits are given to illustrate these different types of solutions.

  14. A New Biomimetic Model for the Active Site of Oxovanadium(IV-Transferrins ? [OVIV(tf

    Directory of Open Access Journals (Sweden)

    Neves Ademir

    1998-01-01

    Full Text Available The synthesis, X-ray crystal structure, and spectroscopic properties of the new coordination compound [OV IV(HBIMETEN], [H3BIMETEN = N , N' - (2-hydroxybenzil -N-(1-methylimidazole-2-yl-methyl-N'-hydroxyethil-ethylenediamine] are reported as V IV O2+ complex example containing phenolate and 1-methylimidazole coordinated simultaneously to the metal center. The EPR and UV-Vis properties of the title compound are similar to those observed in [OV IV(tf].

  15. Solution chemistry of Mo(III) and Mo(IV): Thermodynamic foundation for modeling localized corrosion

    Energy Technology Data Exchange (ETDEWEB)

    Wang Peiming [OLI Systems Inc., 108 American Road, Morris Plains, NJ 07950 (United States); Wilson, Leslie L.; Wesolowski, David J.; Rosenqvist, Joergen [Chemical Sciences Division, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831-6110 (United States); Anderko, Andrzej [OLI Systems Inc., 108 American Road, Morris Plains, NJ 07950 (United States)], E-mail: aanderko@olisystems.com

    2010-05-15

    To investigate the behavior of molybdenum dissolution products in systems that approximate localized corrosion environments, solubility of Mo(III) in equilibrium with solid MoO{sub 2} has been determined at 80 deg. C as a function of solution acidity, chloride concentration and partial pressure of hydrogen. The measurements indicate a strong increase in solubility with acidity and chloride concentration and a weak effect of hydrogen partial pressure. The obtained results have been combined with literature data for systems containing Mo(III), Mo(IV), and Mo(VI) in solutions to develop a comprehensive thermodynamic model of aqueous molybdenum chemistry. The model is based on a previously developed framework for simulating the properties of electrolyte systems ranging from infinite dilution to solid saturation or fused salt limit. To reproduce the measurements, the model assumes the presence of a chloride complex of Mo(III) (i.e., MoCl{sup 2+}) and hydrolyzed species (MoOH{sup 2+}, Mo(OH){sub 2}{sup +}, and Mo(OH){sub 3}{sup 0}) in addition to the Mo{sup 3+} ion. The model generally reproduces the experimental data within experimental scattering and provides a tool for predicting the phase behavior and speciation in complex, concentrated aqueous solutions. Thus, it provides a foundation for simulating the behavior of molybdenum species in localized corrosion environments.

  16. An Application of the PMI Model at the Project Level Evaluation of ESEA Title IV-C Projects.

    Science.gov (United States)

    McBeath, Marcia

    All of the papers presented as part of a symposium concerned the application of the Planning, Monitoring, and Implementation Model (PMI) to the evaluation of the District of Columbia Public Schools' programs supported by the Elementary Secondary Education Act (ESEA) Title IV-C. PMI was developed to provide a model for systematic evaluation of…

  17. Effect of Astragaloside IV on Neural Stem Cell Transplantation in Alzheimer’s Disease Rat Models

    Directory of Open Access Journals (Sweden)

    Hu Haiyan

    2016-01-01

    Full Text Available Stem cell-based therapy is a promising treatment strategy for neurodegenerative diseases such as Alzheimer’s disease (AD. However, the mechanism underlying the maintenance of renewal and replacement capabilities of endogenous progenitor cells or engrafted stem cells in a pathological environment remains elusive. To investigate the effect of astragaloside IV (ASI on the proliferation and differentiation of the engrafted neural stem cells (NSCs, we cultured NSCs from the hippocampus of E14 rat embryos, treated the cells with ASI, and then transplanted the cells into the hippocampus of rat AD models. In vitro experimentation showed that 10−5 M ASI induced NSCs to differentiate into β-tubulin III+ and GFAP+ cells. NSCs transplantation into rat AD models resulted in improvements in learning and memory, especially in the ASI-treated groups. ASI treatment resulted in an increase in the number of β-tubulin III+ cells in the hippocampus. Further investigation showed that ASI inhibited PS1 expression in vitro and in vivo. The high-dose ASI downregulated the Notch intracellular domain, whereas the low-dose ASI increased Notch-1 and NICD. In conclusion, ASI treatment resulted in improvements in learning and memory of AD models by promoting NSC proliferation and differentiation partly through the Notch signal pathway.

  18. Volcanogenic massive sulfide deposits of the world: Database and grade and tonnage models

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Information on VMS deposits from around the world. It also presents new grade and tonnage models for three subtypes of VMS deposits and a text file allowing...

  19. Large Deviations for Stochastic Models of Two-Dimensional Second Grade Fluids

    Energy Technology Data Exchange (ETDEWEB)

    Zhai, Jianliang, E-mail: zhaijl@ustc.edu.cn [University of Science and Technology of China, School of Mathematical Sciences (China); Zhang, Tusheng, E-mail: Tusheng.Zhang@manchester.ac.uk [University of Manchester, School of Mathematics (United Kingdom)

    2017-06-15

    In this paper, we establish a large deviation principle for stochastic models of incompressible second grade fluids. The weak convergence method introduced by Budhiraja and Dupuis (Probab Math Statist 20:39–61, 2000) plays an important role.

  20. Grade Level, Study Time, and Grade Retention and Their Effects on Motivation, Self-Regulated Learning Strategies, and Mathematics Achievement: A Structural Equation Model

    Science.gov (United States)

    Rosário, Pedro; Núñez, José Carlos; Valle, António; González-Pienda, Julio; Lourenço, Abílio

    2013-01-01

    The present study complements previous research findings with new data to improve our understanding of the relationship between motivational variables and academic performance in math mediated by self-regulated learning (SRL). A structural equation model with predictor (i.e., grade retention, grade level, and study time), process (i.e., perceived…

  1. Where and How People Live. Language Arts around the World, Volume IV. Cross-Curricular Activities for Grades 4-6.

    Science.gov (United States)

    McAllister, Elizabeth A.; Hildebrand, Joan M.; Ericson, Joann H.

    Suggesting that students in the intermediate grades can explore the world around them and practice valuable skills in spelling, reading, writing, communication, and language, this book presents cross-curricular units designed to integrate language-arts activities into the study of where and how people live. The units in the book reach diverse…

  2. Integrating model of the Project Independence Evaluation System. Volume IV. Model documentation

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, M L; Allen, B J; Gale, J E; Lutz, M S; O& #x27; Hara, N E; Wood, R K

    1979-02-01

    This volume is the fourth in a series of seven documenting the PIES Integrating Model. It contains detailed descriptions of the basic assumptions behind each of the components of PIES and how they interact with one another. Chapter II of this volume presents the methodology used to integrate supply and demand. It includes a discussion of both the interface between the Demand Model and the equilibrating mechanism and the various supply models via the equilibrating algorithm used by PIES. Chapters III through IX describe each supply submodel in turn: coal, oil, and natural gas supply, utilities, refineries, advanced technologies, and transportation. Code and data documentation are covered elsewhere in this series (Volumes V and VI respectively). PIES is an evolving system. As this document was being prepared, many parts of the model were being modified. This document describes the PIES Integrating Model as of January 1, 1978.

  3. RAGBEEF: a FORTRAN IV implementation of a time-dependent model for radionuclide contamination of beef

    Energy Technology Data Exchange (ETDEWEB)

    Pleasant, J C; McDowell-Boyer, L M; Killough, G G

    1982-06-01

    RAGBEEF is a FORTRAN IV program that calculates radionuclide concentrations in beef as a result of ingestion of contaminated feeds, pasture, and pasture soil by beef cattle. The model implemented by RAGBEEF is dynamic in nature, allowing the user to consider age- and season-dependent aspects of beef cattle management in estimating concentrations in beef. It serves as an auxiliary code to RAGTIME, previously documented by the authors, which calculates radionuclide concentrations in agricultural crops in a dynamic manner, but evaluates concentrations in beef for steady-state conditions only. The time-dependent concentrations in feeds, pasture, and pasture soil generated by RAGTIME are used as input to the RAGBEEF code. RAGBEEF, as presently implemented, calculates radionuclide concentrations in the muscle of age-based cohorts in a beef cattle herd. Concentrations in the milk of lactating cows are also calculated, but are assumed age-dependent as in RAGTIME. Radionuclide concentrations in beef and milk are described in RAGBEEF by a system of ordinary linear differential equations in which the transfer rate of radioactivity between compartments is proportional to the inventory of radioactivity in the source compartment. This system is solved by use of the GEAR package for solution of systems of ordinary differential equations. The accuracy of this solution is monitored at various check points by comparison with explicit solutions of Bateman-type equations. This report describes the age- and season-dependent considerations making up the RAGBEEF model, as well as presenting the equations which describe the model and a documentation of the associated computer code. Listings of the RAGBEEF and updated RAGTIME codes are provided in appendices, as are the results of a sample run of RAGBEEF and a description of recent modifications to RAGTIME.

  4. Thermochromic behavior of vanadium(IV) alkoxides in solution: a molecular modeling approach; Termocromismo em solucoes de alcoxidos de vanadio(IV): uma abordagem pela modelagem molecular

    Energy Technology Data Exchange (ETDEWEB)

    Freitas, Alexandre C. de; Westrup, Katia C. M.; Nunes, Giovana G.; Gulin, Denis J.; Haiduke, Roberto L. A.; Soares, Jaisa F.; Sa, Eduardo L. de [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Dept. de Quimica

    2010-07-01

    The thermochromic behavior exhibited by vanadium(IV) alkoxides, [V{sub 2}(mu-OPr{sup i}){sub 2}(OPr{sup i}){sub 6}] and [V{sub 2}(m-ONep){sub 2}(ONep){sub 6}], OPr{sup i} = isopropoxide and ONep = neopentoxide, was studied by molecular modeling using DFT, TDDFT and INDO/S methods. The vibrational and electronic spectra calculated for [V{sub 2}(mu-OPr{sup i}){sub 2}(OPr{sup i}){sub 6}] were very similar to the experimental data registered for crystalline samples of the complex and for its solutions at low temperature (< 210 K), while spectra recorded at high temperature (> 315 K) were compatible with those calculated for the monomeric form, [V(OPr{sup i}){sub 4}]. These results consistently point to a monomer/dimer equilibrium as an explanation for the solution thermochromism of {l_brace}V(OPr{sup i})-4{r_brace}{sub n}. In spite of the structural similarity between [V{sub 2}(mu-ONep){sub 2}(ONep){sub 6}] and [V{sub 2}(mu-OPr{sup i}){sub 2}(OPr{sup i}){sub 6}] in the solid state, the thermochromic behavior of the former could not be explained by the same model, and the possibility of tetranuclear aggregation at low temperatures was also investigated. (author)

  5. Bayesian Comparison of Alternative Graded Response Models for Performance Assessment Applications

    Science.gov (United States)

    Zhu, Xiaowen; Stone, Clement A.

    2012-01-01

    This study examined the relative effectiveness of Bayesian model comparison methods in selecting an appropriate graded response (GR) model for performance assessment applications. Three popular methods were considered: deviance information criterion (DIC), conditional predictive ordinate (CPO), and posterior predictive model checking (PPMC). Using…

  6. Gadobutrol Versus Gadopentetate Dimeglumine or Gadobenate Dimeglumine Before DCE-MRI in Diagnosing Patients With Multiple Sclerosis, Grade II-IV Glioma, or Brain Metastases

    Science.gov (United States)

    2016-11-15

    Adult Anaplastic (Malignant) Meningioma; Adult Anaplastic Astrocytoma; Adult Anaplastic Ependymoma; Adult Anaplastic Oligodendroglioma; Adult Brain Stem Glioma; Adult Choroid Plexus Neoplasm; Adult Diffuse Astrocytoma; Adult Ependymoblastoma; Adult Ependymoma; Adult Giant Cell Glioblastoma; Adult Glioblastoma; Adult Gliosarcoma; Adult Grade II Meningioma; Adult Medulloblastoma; Adult Mixed Glioma; Adult Oligodendroglioma; Adult Papillary Meningioma; Adult Pineal Gland Astrocytoma; Adult Pineoblastoma; Adult Primary Melanocytic Lesion of Meninges; Adult Supratentorial Primitive Neuroectodermal Tumor; Malignant Adult Intracranial Hemangiopericytoma; Metastatic Malignant Neoplasm in the Brain; Multiple Sclerosis; Recurrent Adult Brain Neoplasm

  7. Generation IV benchmarking of TRISO fuel performance models under accident conditions: Modeling input data

    Energy Technology Data Exchange (ETDEWEB)

    Collin, Blaise P. [Idaho National Laboratory (INL), Idaho Falls, ID (United States)

    2014-09-01

    This document presents the benchmark plan for the calculation of particle fuel performance on safety testing experiments that are representative of operational accidental transients. The benchmark is dedicated to the modeling of fission product release under accident conditions by fuel performance codes from around the world, and the subsequent comparison to post-irradiation experiment (PIE) data from the modeled heating tests. The accident condition benchmark is divided into three parts: the modeling of a simplified benchmark problem to assess potential numerical calculation issues at low fission product release; the modeling of the AGR-1 and HFR-EU1bis safety testing experiments; and, the comparison of the AGR-1 and HFR-EU1bis modeling results with PIE data. The simplified benchmark case, thereafter named NCC (Numerical Calculation Case), is derived from ''Case 5'' of the International Atomic Energy Agency (IAEA) Coordinated Research Program (CRP) on coated particle fuel technology [IAEA 2012]. It is included so participants can evaluate their codes at low fission product release. ''Case 5'' of the IAEA CRP-6 showed large code-to-code discrepancies in the release of fission products, which were attributed to ''effects of the numerical calculation method rather than the physical model''[IAEA 2012]. The NCC is therefore intended to check if these numerical effects subsist. The first two steps imply the involvement of the benchmark participants with a modeling effort following the guidelines and recommendations provided by this document. The third step involves the collection of the modeling results by Idaho National Laboratory (INL) and the comparison of these results with the available PIE data. The objective of this document is to provide all necessary input data to model the benchmark cases, and to give some methodology guidelines and recommendations in order to make all results suitable for comparison

  8. Generation IV benchmarking of TRISO fuel performance models under accident conditions: Modeling input data

    Energy Technology Data Exchange (ETDEWEB)

    Collin, Blaise P. [Idaho National Laboratory (INL), Idaho Falls, ID (United States)

    2014-09-01

    This document presents the benchmark plan for the calculation of particle fuel performance on safety testing experiments that are representative of operational accidental transients. The benchmark is dedicated to the modeling of fission product release under accident conditions by fuel performance codes from around the world, and the subsequent comparison to post-irradiation experiment (PIE) data from the modeled heating tests. The accident condition benchmark is divided into three parts: the modeling of a simplified benchmark problem to assess potential numerical calculation issues at low fission product release; the modeling of the AGR-1 and HFR-EU1bis safety testing experiments; and, the comparison of the AGR-1 and HFR-EU1bis modeling results with PIE data. The simplified benchmark case, thereafter named NCC (Numerical Calculation Case), is derived from ''Case 5'' of the International Atomic Energy Agency (IAEA) Coordinated Research Program (CRP) on coated particle fuel technology [IAEA 2012]. It is included so participants can evaluate their codes at low fission product release. ''Case 5'' of the IAEA CRP-6 showed large code-to-code discrepancies in the release of fission products, which were attributed to ''effects of the numerical calculation method rather than the physical model''[IAEA 2012]. The NCC is therefore intended to check if these numerical effects subsist. The first two steps imply the involvement of the benchmark participants with a modeling effort following the guidelines and recommendations provided by this document. The third step involves the collection of the modeling results by Idaho National Laboratory (INL) and the comparison of these results with the available PIE data. The objective of this document is to provide all necessary input data to model the benchmark cases, and to give some methodology guidelines and recommendations in order to make all results suitable for comparison

  9. GEN-IV BENCHMARKING OF TRISO FUEL PERFORMANCE MODELS UNDER ACCIDENT CONDITIONS MODELING INPUT DATA

    Energy Technology Data Exchange (ETDEWEB)

    Collin, Blaise Paul [Idaho National Laboratory

    2016-09-01

    This document presents the benchmark plan for the calculation of particle fuel performance on safety testing experiments that are representative of operational accidental transients. The benchmark is dedicated to the modeling of fission product release under accident conditions by fuel performance codes from around the world, and the subsequent comparison to post-irradiation experiment (PIE) data from the modeled heating tests. The accident condition benchmark is divided into three parts: • The modeling of a simplified benchmark problem to assess potential numerical calculation issues at low fission product release. • The modeling of the AGR-1 and HFR-EU1bis safety testing experiments. • The comparison of the AGR-1 and HFR-EU1bis modeling results with PIE data. The simplified benchmark case, thereafter named NCC (Numerical Calculation Case), is derived from “Case 5” of the International Atomic Energy Agency (IAEA) Coordinated Research Program (CRP) on coated particle fuel technology [IAEA 2012]. It is included so participants can evaluate their codes at low fission product release. “Case 5” of the IAEA CRP-6 showed large code-to-code discrepancies in the release of fission products, which were attributed to “effects of the numerical calculation method rather than the physical model” [IAEA 2012]. The NCC is therefore intended to check if these numerical effects subsist. The first two steps imply the involvement of the benchmark participants with a modeling effort following the guidelines and recommendations provided by this document. The third step involves the collection of the modeling results by Idaho National Laboratory (INL) and the comparison of these results with the available PIE data. The objective of this document is to provide all necessary input data to model the benchmark cases, and to give some methodology guidelines and recommendations in order to make all results suitable for comparison with each other. The participants should read

  10. Properties of type IV plaster considering variation in the mold/model position during setting stage

    Directory of Open Access Journals (Sweden)

    Tarcisio José de Arruda Paes Junior

    2010-04-01

    Full Text Available Objective: To assess the influence of the position of the mold during the setting stage of type IV stone plaster Durone (Dentsply Ind. Com., Rio de Janeiro, Brazil, on the following properties: surface hardness and roughness. Methods: For the roughness test, two groups (n=6 in the form of pellets were prepared. In the first group, the surface of the base of the device was turned down during the plaster setting stage (N, in the second group this position was inverted, which has been described as an act of capsize it (E. For analysis, a roughness meter with reading precision of 0.01 μm was used. With regard to the hardness analysis, two groups with conical-shaped samples were obtained. The plasters were left to set under the same conditions of the mold/model position described for the previous experiment. Hardness measurement was performed in a durometer with a spherical penetrating tip for Rockwell readout. Three measurements were performed for each test specimen in both tests. Results: The hardness (N - 39.8, standard deviation = 3.3, E - 30.8, standard deviation = 5.6 and roughness data (N - 0.67, standard deviation = 0.17, E - 0.74, standard deviation = 0.13 submitted to the Student’s-t test (5% showed no statistically significant differences for the roughness test (0.489, but showed statistically significant differences for the hardness test (0.014. Conclusion: The variation in the mold/model position influenced the final characteristics of the specimens in terms of hardness, since those obtained with the capsize technique showed lower surface hardness, whereas for roughness these differences were not statistically significant.

  11. Modeling Enclosure Design in Above-Grade Walls

    Energy Technology Data Exchange (ETDEWEB)

    Lstiburek, J. [Building Science Corporation, Westford, MA (United States); Ueno, K. [Building Science Corporation, Westford, MA (United States); Musunuru, S. [Building Science Corporation, Westford, MA (United States)

    2016-03-01

    Building Science Corporation modeled typically well-performing wall assemblies using Wärme und Feuchte instationär (WUFI) Version 5.3 software and demonstrated that these models agree with historic experience when calibrated and modeled correctly. This technical report provides a library of WUFI modeling input data and results. Within the limits of existing experience, this information can be generalized for applications to a broad population of houses.

  12. Numerical modeling of isothermal compositional grading by convex splitting methods

    KAUST Repository

    Li, Yiteng

    2017-04-09

    In this paper, an isothermal compositional grading process is simulated based on convex splitting methods with the Peng-Robinson equation of state. We first present a new form of gravity/chemical equilibrium condition by minimizing the total energy which consists of Helmholtz free energy and gravitational potential energy, and incorporating Lagrange multipliers for mass conservation. The time-independent equilibrium equations are transformed into a system of transient equations as our solution strategy. It is proved our time-marching scheme is unconditionally energy stable by the semi-implicit convex splitting method in which the convex part of Helmholtz free energy and its derivative are treated implicitly and the concave parts are treated explicitly. With relaxation factor controlling Newton iteration, our method is able to converge to a solution with satisfactory accuracy if a good initial estimate of mole compositions is provided. More importantly, it helps us automatically split the unstable single phase into two phases, determine the existence of gas-oil contact (GOC) and locate its position if GOC does exist. A number of numerical examples are presented to show the performance of our method.

  13. Molecular Docking Study Based on Pharmacophore Modeling for Novel PhosphodiesteraseIV Inhibitors.

    Science.gov (United States)

    Çifci, Gülşah; Aviyente, Viktorya; Akten, E Demet

    2012-07-01

    In this study, pharmacophore modelling was carried out for novel PhosphodiesteraseIV (PDEIV) inhibitors. A pharmacophore-based virtual screening, which resulted in 1959 hit compounds was performed with six chemical databases. The pharmacophore screening was proven to be successful in discriminating active and inactive inhibitors using a set of compounds with known activity obtained from ChEMBL database. Furthermore, the Lipinski's rule of five was applied for physicochemical filtering of the hit molecules and this yielded 1840 compounds. Three docking software tools, AutoDock 4.0, AutoDock Vina, and Gold v5.1 were used for the docking process. All 1840 compounds and the known selective inhibitor, rolipram, were docked into the active site of the target protein. A total of 234 compounds with all three scoring values higher than those of rolipram were determined with the three docking tools. The interaction maps of 14 potent inhibitors complexed with PDEIV B and D isoforms have been analyzed and seven key residues (Asn 395, Gln 443, Tyr 233, Ile 410, Phe 446, Asp 392, Thr 407) were found to interact with more than 80 % of the potent inhibitors. For each one of the 234 hit compounds, using the bound conformation with the highest AutoDock score, the interacting residues were determined. 117 out of 234 compounds are found to interact with at least five of the seven key residues and these were selected for further evaluation. The conformation with the highest AutoDock score for each 117 compounds were rescored using the DSX scoring function. This yielded a total of 101 compounds with better score values than the natural ligand rolipram. For ADME/TOX calculations, the FAF-Drugs2 server was used and 32 out of 101 compounds were found to be non-toxic. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Coverage of the DSM-IV-TR/DSM-5 Section II Personality Disorders With the DSM-5 Dimensional Trait Model.

    Science.gov (United States)

    Rojas, Stephanie L; Widiger, Thomas A

    2017-08-01

    Section III of DSM-5, for emerging measures and models, includes a five-domain, 25-trait model, assessed by the Personality Inventory for DSM-5. A primary concern with respect to the trait model is its coverage of the DSM-IV-TR personality disorder syndromes (all of which were retained in DSM-5). The current study considered not only total scale scores of three independent measures of DSM-IV-TR personality disorders but also the coverage of each diagnostic criterion included within six personality disorders: antisocial, borderline, avoidant, dependent, narcissistic, and obsessive-compulsive. Participants were 425 community adults, all of whom had received mental health treatment (36% currently; 75% within the past year). Results provided support for the coverage of the diagnostic criteria for the antisocial, borderline, avoidant, dependent, and narcissistic personality disorders. Coverage could perhaps be improved for a few of the criteria for obsessive-compulsive personality disorder.

  15. miR-21 and 221 upregulation and miR-181b downregulation in human grade II-IV astrocytic tumors.

    Science.gov (United States)

    Conti, Alfredo; Aguennouz, M'Hammed; La Torre, Domenico; Tomasello, Chiara; Cardali, Salvatore; Angileri, Filippo F; Maio, Francesca; Cama, Annamaria; Germanò, Antonino; Vita, Giuseppe; Tomasello, Francesco

    2009-07-01

    MicroRNAs (miRNAs) are small noncoding regulatory RNAs that reduce stability and/or translation of fully or partially sequence-complementary target mRNAs. Recent evidence indicates that miRNAs can function both as tumor suppressors and as oncogenes. It has been demonstrated that in glioblastoma multiforme miR-21 and 221 are upregulated whereas miR-128 and 181 are downregulated. Expression of miR-21, 221, 128a, 128b, 128c, 181a, 181b, 181c was studied using real-time quantitative reverse transcriptase polymerase chain reaction and northern blotting for human astrocytic tumors with different grade of malignancy. miR-21 and 221 were overexpressed in glioma samples, whereas miRNA 181b was downregulated compared with normal brain tissue. miRNA-21 was hyperexpressed in all tumor samples whereas higher levels of miRNA-221 were found in high-grade gliomas. This study is the first analysis of miRNAs in astrocytic tumor at different stages of malignancy. The different expression pattern observed in tumors at different stages of malignancy is probably dependent on the cell-specific repertoire of target genes of tumors sharing different molecular pathways activity and suggests miRNAs may have also a place in diagnosis and staging of brain tumors.

  16. Structural Validity of CLASS K-3 in Primary Grades: Testing Alternative Models

    Science.gov (United States)

    Sandilos, Lia E.; Shervey, Sarah Wollersheim; DiPerna, James C.; Lei, Puiwa; Cheng, Weiyi

    2017-01-01

    This study examined the internal structure of the Classroom Assessment Scoring System (CLASS; K-3 version). The original CLASS K-3 model (Pianta, La Paro, & Hamre, 2008) and 5 alternative models were tested using confirmatory factor analysis with a sample of first- and second-grade classrooms (N = 141). Findings indicated that a slightly…

  17. An Investigation of Fraction Models in Early Elementary Grades: A Mixed-Methods Approach

    Science.gov (United States)

    Wilkerson, Trena L.; Cooper, Susan; Gupta, Dittika; Montgomery, Mark; Mechell, Sara; Arterbury, Kristin; Moore, Sherrie; Baker, Betty Ruth; Sharp, Pat T.

    2015-01-01

    This study examines the effect varying models have on student understanding of fractions. The study addressed the question of what students know and understand about fractional concepts through the use of discrete and continuous models. A sample of 54 students in kindergarten and 3rd grade were given an interview pretest, participated in…

  18. Middle Grades' School Models and Their Impact on Early Adolescent Self-Esteem

    Science.gov (United States)

    Booth, Margaret Zoller; Sheehan, Heather Chase; Earley, Mark A.

    2007-01-01

    Throughout the world, school grade structures are most variable during the early adolescent years when students can find themselves in a variety of school models. This paper investigates the impact of two popular school models in the United States (middle school and K-8) on the self-esteem and self-concept of early adolescents. Based on mixed…

  19. Middle Grades' School Models and Their Impact on Early Adolescent Self-Esteem

    Science.gov (United States)

    Booth, Margaret Zoller; Sheehan, Heather Chase; Earley, Mark A.

    2007-01-01

    Throughout the world, school grade structures are most variable during the early adolescent years when students can find themselves in a variety of school models. This paper investigates the impact of two popular school models in the United States (middle school and K-8) on the self-esteem and self-concept of early adolescents. Based on mixed…

  20. The i-V curve curve characteristics of burner-stabilized premixed flames: detailed and reduced models

    CERN Document Server

    Han, Jie; Casey, Tiernan A; Bisetti, Fabrizio; Im, Hong G; Chen, Jyh-Yuan

    2016-01-01

    The i-V curve describes the current drawn from a flame as a function of the voltage difference applied across the reaction zone. Since combustion diagnostics and flame control strategies based on electric fields depend on the amount of current drawn from flames, there is significant interest in modeling and understanding i-V curves. We implement and apply a detailed model for the simulation of the production and transport of ions and electrons in one dimensional premixed flames. An analytical reduced model is developed based on the detailed one, and analytical expressions are used to gain insight into the characteristics of the i-V curve for various flame configurations. In order for the reduced model to capture the spatial distribution of the electric field accurately, the concept of a dead zone region, where voltage is constant, is introduced, and a suitable closure for the spatial extent of the dead zone is proposed and validated. The results from the reduced modeling framework are found to be in good agre...

  1. The grain grading model and prediction of deleterious porosity of cement-based materials

    Institute of Scientific and Technical Information of China (English)

    FENG Qi; LIU Jun-zhe

    2008-01-01

    The calculating model for the packing degree of spherical particles system was modified. The grain grading model of cement-based materials was established and could be applied in the global grading system as well as in the nano-fiber reinforced system. According to the grain grading model, two kinds of mortar were de-signed by using the global grain materials and nano-fiber materials such as fly ash, silica fume and NR powder.In this paper, the densities of two above systems cured for 90d were tested and the relationship of deleterious porosity and the total porosity of hardened mortar was discussed. Research results show that nano-fiber materialsuch as NR powder can increase the density of cement-based materials. The relationship of deleterious porosity and the total porosity of hardened mortar accords with logarithmic curve. The deleterious porosity and the ration-ality of the grading can be roughly predicted through calculating the packing degree by the grain grading model of cement-based materials.

  2. What Is Known about Elementary Grades Mathematical Modelling

    Directory of Open Access Journals (Sweden)

    Micah S. Stohlmann

    2016-01-01

    Full Text Available Mathematical modelling has often been emphasized at the secondary level, but more research is needed at the elementary level. This paper serves to summarize what is known about elementary mathematical modelling to guide future research. A targeted and general literature search was conducted and studies were summarized based on five categories: content of mathematical modelling intervention, assessment data collected, unit of analysis studied, population, and effectiveness. It was found that there were three main units of analysis into which the studies could be categorized: representational and conceptual competence, models created, and student beliefs. The main findings from each of these units of analysis are discussed along with future research that is needed.

  3. The Effect of Scheduling Models for Introductory Algebra on 9th-Grade Students, Test Scores and Grades

    Science.gov (United States)

    O'Hanlon, Angela L.

    2011-01-01

    The purpose of the study was to determine the effect of pacing and scheduling of algebra coursework on assigned 9th-grade students who traditionally would qualify for pre-algebra instruction and same course 9th-grade students who traditionally would qualify for standard algebra instruction. Students were selected based on completion of first-year…

  4. Assembly Variation Identification of High Pressure Spool by Response Surface Based Model Updating Using IV-optimal Designs

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ziyang; XIE Shousheng; HU Jinhai; MIAO Zhuoguang; WANG Lei

    2012-01-01

    This article,in order to improve the assembly of the high-pressure spool,presents an assembly variation identification method achieved by response surface method (RSM)-based model updating using IV-optimal designs.The method involves screening out non-relevant assembly parameters using IV-optimal designs and the preload of the joints is chosen as the input features and modal frequency is the only response feature.Emphasis is placed on the construction of response surface models including the interactions between the bolted joints by which the non-linear relationship between the assembly variation caused by the changes of preload and the output frequency variation is established.By achieving an optimal process of selected variables in the model,assembly variation can be identified.With a case study of the laboratory bolted disks as an example,the proposed method is verified and it gives enough accuracy in variation identification.It has been observed that the first-order response surface models considering the interactions between the bolted joints based on the IV-optimal criterion are adequate for assembly purposes.

  5. Mouse models of myeloproliferative neoplasms: JAK of all grades

    Directory of Open Access Journals (Sweden)

    Juan Li

    2011-05-01

    Full Text Available In 2005, several groups identified a single gain-of-function point mutation in the JAK2 kinase that was present in the majority of patients with myeloproliferative neoplasms (MPNs. Since this discovery, much effort has been dedicated to understanding the molecular consequences of the JAK2V617F mutation in the haematopoietic system. Three waves of mouse models have been produced recently (bone marrow transplantation, transgenic and targeted knock-in, which have facilitated the understanding of the molecular pathogenesis of JAK2V617F-positive MPNs, providing potential platforms for designing and validating novel therapies in humans. This Commentary briefly summarises the first two types of mouse models and then focuses on the more recently generated knock-in models.

  6. Self-diffusion nuclear magnetic resonance, microstructure transitions, and solubilization capacity of phytosterols and cholesterol in Winsor IV food-grade microemulsions

    DEFF Research Database (Denmark)

    Spernath, Aviram; Yaghmur, Anan; Aserin, Abraham

    2003-01-01

    Microemulsions are of growing interest to the food industry as vehicles for delivering and enhancing solubilization of natural food supplements with nutritional and health benefits. The incorporation of molecular phytosterols, cholesterol-lowering agents, in food products is of great interest...... to the food industry. In this work is demonstrated the use of water dilutable food-grade microemulsions consisting of ethoxylated sorbitan ester (Tween 60), water, R-(+)-limonene, ethanol, and propylene glycol as vehicles for enhancing the phytosterols solubilization. Phytosterols were solubilized up to 12......:1:3] was correlated to the microstructure transitions along the dilution line. Structural aspects were studied by self-diffusion NMR spectroscopy. The ability of phytosterols to compete with cholesterol for penetration into bile salt micelles in the gut may be limited to rich aqueous systems (O/W microemulsion)....

  7. The CA model for traffic-flow at the grade roundabout crossing

    Institute of Scientific and Technical Information of China (English)

    Chen Rui-Xiong; Bai Ke-Zhao; Liu Mu-Ren

    2006-01-01

    The cellular automaton model is suggested to describe the traffic-flow at the grade roundabout crossing. After the simulation with computer, the fundamental properties of this model have been revealed. Analysing this kind of road structure, this paper transforms the grade roundabout crossing with inner-roundabout-lane and outer-roundabout-lane into a configuration with many bottlenecks. Because of the self-organization, the traffic flow remains unblocked under a certain vehicle density. Some results of the simulation are close to the actual design parameter.

  8. Modeling Enclosure Design in Above-Grade Walls

    Energy Technology Data Exchange (ETDEWEB)

    Lstiburek, J. [Building Science Corporation, Westford, MA (United States); Ueno, K. [Building Science Corporation, Westford, MA (United States); Musunuru, S. [Building Science Corporation, Westford, MA (United States)

    2016-03-01

    This report describes the modeling of typical wall assemblies that have performed well historically in various climate zones. The WUFI (Warme und Feuchte instationar) software (Version 5.3) model was used. A library of input data and results are provided. The provided information can be generalized for application to a broad population of houses, within the limits of existing experience. The WUFI software model was calibrated or tuned using wall assemblies with historically successful performance. The primary performance criteria or failure criteria establishing historic performance was moisture content of the exterior sheathing. The primary tuning parameters (simulation inputs) were airflow and specifying appropriate material properties. Rational hygric loads were established based on experience - specifically rain wetting and interior moisture (RH levels). The tuning parameters were limited or bounded by published data or experience. The WUFI templates provided with this report supply useful information resources to new or less-experienced users. The files present various custom settings that will help avoid results that will require overly conservative enclosure assemblies. Overall, better material data, consistent initial assumptions, and consistent inputs among practitioners will improve the quality of WUFI modeling, and improve the level of sophistication in the field.

  9. Modelling transport of graded sediment under partial transport conditions

    NARCIS (Netherlands)

    Tuijnder, Arjan; Ribberink, Jan S.; Hulscher, Suzanne J.M.H.; Weerts, H.J.T.; Ritsema, I.L; van Os, A.G.

    2006-01-01

    Tentative plans are presented for research on the modelling of i) selective sediment transport in suspension and as bed-load, and ii) large-scale morphology in mixed sand-gravel bed rivers. Since the planning of the research is still in its early stages, the plans are flexible. Please feel free to

  10. Colorado Model Content Standards for Theatre: Suggested Grade Level Expectations.

    Science.gov (United States)

    Colorado State Dept. of Education, Denver.

    This booklet lists six model content standards in theater arts for elementary and secondary school students in the state of Colorado. The six standards cited in the booklet are: (1) Students develop interpersonal skills and problem-solving capabilities through group interaction and artistic collaboration; (2) Students understand and apply the…

  11. Persistent improved results after adding vincristine and bleomycin to a cyclophosphamide/hydroxorubicin/Vm-26/prednisone combination (CHVmP) in stage III-IV intermediate- and high-grade non-Hodgkin's lymphoma. The EORTC Lymphoma Cooperative Group.

    Science.gov (United States)

    Meerwaldt, J H; Carde, P; Somers, R; Thomas, J; Kluin-Nelemans, J C; Bron, D; Noordijk, E M; Cosset, J M; Bijnens, L; Teodorovic, I; Hagenbeek, A

    1997-01-01

    CHOP has been and still is regarded by many as the 'standard' treatment of advanced non-Hodgkin's lymphoma. In 1980 the EORTC Lymphoma Cooperative Group started a study to evaluate the addition of vincristine and bleomycin to its standard four-drug combination chemotherapy, CHVmP (cyclophosphamide, hydroxorubicin, Vm-26, prednisone). Eligible patients were stage III or IV, intermediate- to high-grade non-Hodgkin's lymphoma (Working Formulation E-I). One-hundred-eighty-nine patients were entered, of whom 140 were eligible and evaluable. A previous report showed an improved response rate and failure-free survival (FFS) and overall survival for the combination CHVmP-VB. At ten years, the outcome still favors the addition of vincristine and bleomycin. The FFS was 34% vs. 23% and the overall survival 34% vs 22%. This difference was mainly due to a difference in CR rate (74% vs. 49%), Relapse-free survival for patients reaching a CR was the same in both arms. When the patients were grouped according to the International Prognostic Factor Index, no statistically significant difference could be observed in favor of one treatment within either group. This trial clearly demonstrates the benefit gained by the addition of vincristine and bleomycin to 'standard' chemotherapy for intermediate and high-grade non-Hodgkin's lymphoma.

  12. Sediment-hosted gold deposits of the world: database and grade and tonnage models

    Science.gov (United States)

    Berger, Vladimir I.; Mosier, Dan L.; Bliss, James D.; Moring, Barry C.

    2014-01-01

    All sediment-hosted gold deposits (as a single population) share one characteristic—they all have disseminated micron-sized invisible gold in sedimentary rocks. Sediment-hosted gold deposits are recognized in the Great Basin province of the western United States and in China along with a few recognized deposits in Indonesia, Iran, and Malaysia. Three new grade and tonnage models for sediment-hosted gold deposits are presented in this paper: (1) a general sediment-hosted gold type model, (2) a Carlin subtype model, and (3) a Chinese subtype model. These models are based on grade and tonnage data from a database compilation of 118 sediment-hosted gold deposits including a total of 123 global deposits. The new general grade and tonnage model for sediment-hosted gold deposits (n=118) has a median tonnage of 5.7 million metric tonnes (Mt) and a gold grade of 2.9 grams per tonne (g/t). This new grade and tonnage model is remarkable in that the estimated parameters of the resulting grade and tonnage distributions are comparable to the previous model of Mosier and others (1992). A notable change is in the reporting of silver in more than 10 percent of deposits; moreover, the previous model had not considered deposits in China. From this general grade and tonnage model, two significantly different subtypes of sediment-hosted gold deposits are differentiated: Carlin and Chinese. The Carlin subtype includes 88 deposits in the western United States, Indonesia, Iran, and Malaysia, with median tonnage and grade of 7.1 Mt and 2.0 g/t Au, respectively. The silver grade is 0.78 g/t Ag for the 10th percentile of deposits. The Chinese subtype represents 30 deposits in China, with a median tonnage of 3.9 Mt and medium grade of 4.6 g/t Au. Important differences are recognized in the mineralogy and alteration of the two sediment-hosted gold subtypes such as: increased sulfide minerals in the Chinese subtype and decalcification alteration dominant in the Carlin type. We therefore

  13. Using Clinician-Rated Five-Factor Model Data to Score the DSM–IV Personality Disorders

    OpenAIRE

    Miller, Joshua D.; Maples, Jessica; Few, Lauren R.; Morse, Jennifer Q.; Yaggi, Kirsten E.; Pilkonis, Paul A.

    2010-01-01

    Proposals suggest that many or all of the Diagnostic and Statistical Manual of Mental Disorders (4th ed. [DSM–IV]; American Psychiatric Association, 1994) personality disorders (PDs) may be omitted from the DSM (5th ed.; DSM–V ) and replaced with a dimensional trait model of personality pathology (Krueger, Skodol, Livesley, Shrout, & Huang, 2007; Skodol, 2009). Several authors have expressed concerns that this may be difficult for clinicians and researchers who are more comfortable with the e...

  14. Density and solidiifcation feeding model of vacuum counter-pressure cast aluminum alloy under grade-pressuring conditions

    Institute of Scientific and Technical Information of China (English)

    Qing-song Yan; Huan Yu; Gang Lu; Bo-wen Xiong; Suai Xu

    2016-01-01

    The density of vacuum counter-pressure cast aluminum alloy samples under grade-pressuring condition was studied. The effect of grade pressure difference and time on the density of aluminum aloys was discussed, and the solidiifcation feeding model under grade-pressuring condition was established. The results indicate the grade-pressured solidiifcation feeding ability of vacuum counter-pressure casting mainly depends on grade pressure difference and time. With the increase of grade pressure difference, the density of al the aluminum aloy samples increases, and the trend of change in density from the pouring gate to the top location is first decreasing gradually and then increasing. In addition, in obtaining the maximum density, the optimal grade-pressuring time is different for samples with different wal thicknesses, and the solidiifcation time when the solid volume fraction of aluminum aloy reaches about 0.65 appears to be the optimal beginning time for grade-pressuring.

  15. Preparing clinical-grade myeloid dendritic cells by electroporation-mediated transfection of in vitro amplified tumor-derived mRNA and safety testing in stage IV malignant melanoma

    Directory of Open Access Journals (Sweden)

    Allred Jacob B

    2006-08-01

    Full Text Available Abstract Background Dendritic cells (DCs have been used as vaccines in clinical trials of immunotherapy of cancer and other diseases. Nonetheless, progress towards the use of DCs in the clinic has been slow due in part to the absence of standard methods for DC preparation and exposure to disease-associated antigens. Because different ex vivo exposure methods can affect DC phenotype and function differently, we studied whether electroporation-mediated transfection (electrotransfection of myeloid DCs with in vitro expanded RNA isolated from tumor tissue might be feasible as a standard physical method in the preparation of clinical-grade DC vaccines. Methods We prepared immature DCs (IDCs from CD14+ cells isolated from leukapheresis products and extracted total RNA from freshly resected melanoma tissue. We reversely transcribed the RNA while attaching a T7 promoter to the products that we subsequently amplified by PCR. We transcribed the amplified cDNA in vitro and introduced the expanded RNA into IDCs by electroporation followed by DC maturation and cryopreservation. Isolated and expanded mRNA was analyzed for the presence of melanoma-associated tumor antigens gp100, tyrosinase or MART1. To test product safety, we injected five million DCs subcutaneously at three-week intervals for up to four injections into six patients suffering from stage IV malignant melanoma. Results Three preparations contained all three transcripts, one isolate contained tyrosinase and gp100 and one contained none. Electrotransfection of DCs did not affect viability and phenotype of fresh mature DCs. However, post-thaw viability was lower (69 ± 12 percent in comparison to non-electroporated cells (82 ± 12 percent; p = 0.001. No patient exhibited grade 3 or 4 toxicity upon DC injections. Conclusion Standardized preparation of viable clinical-grade DCs transfected with tumor-derived and in vitro amplified mRNA is feasible and their administration is safe.

  16. Hierarchy and Psychometric Properties of ADHD Symptoms in Spanish Children: An Application of the Graded Response Model

    Science.gov (United States)

    Arias, Victor B.; Nuñez, Daniel E.; Martínez-Molina, Agustín; Ponce, Fernando P.; Arias, Benito

    2016-01-01

    The Diagnostic and Statistical Manual of Mental Disorders (DSM) diagnostic criteria assume that the 18 symptoms carry the same weight in an Attention Deficit with Hyperactivity Disorder (ADHD) diagnosis and bear the same discriminatory capacity. However, it is reasonable to think that symptoms may differ in terms of severity and even in the reliability with they represent the disorder. To test this hypothesis, the aim of this study was to calibrate in a sample of Spanish children (age 4–7; n = 784) a scale for assessing the symptoms of ADHD proposed by Diagnostic and Statistical Manual of Mental Disorders, IV-TR within the framework of Item Response Theory. Samejima’s Graded Response Model was used as a method for estimating the item difficulty and discrimination parameters. The results showed that ADHD subscales (Attention Deficit and Hyperactivity / Impulsivity) had good psychometric properties and had also a good fit to the model. However, relevant differences between symptoms were observed at the level of severity, informativeness and reliability for the assessment of ADHD. This finding suggests that it would be useful to identify the symptoms that are more important than the others with regard to diagnosing ADHD. PMID:27736911

  17. The three year course of alcohol use disorders in the general population: DSM-IV, ICD-10 and the Craving Withdrawal Model

    NARCIS (Netherlands)

    C. de Bruijn; W. van den Brink; R. de Graaf; W.A.M. Vollebergh

    2006-01-01

    To determine the course of alcohol use disorders (AUD) in a prospective general population study using three different classification systems: Diagnostic and Statistical Manual version IV (DSM-IV), International Classification of Diseases version 10 (ICD-10) and the craving withdrawal model (CWM). T

  18. Satisfaction Ratings of QOLPAV: Psychometric Properties Based on the Graded Response Model

    Science.gov (United States)

    Chen, Ssu-Kuang; Hwang, Fang-Ming; Lin, Sunny S. J.

    2013-01-01

    A scale measuring quality of life (QOL) is important in adolescent research. Using the graded response model (GRM), this study evaluates the psychometric properties of the satisfaction ratings of the Quality of Life Profile Adolescent Version (QOLPAV). Data for 1,392 adolescents were used to check IRT assumptions such as unidimensionality and…

  19. A Structural Equation Model of the Writing Process in Typically-Developing Sixth Grade Children

    Science.gov (United States)

    Koutsoftas, Anthony D.; Gray, Shelley

    2013-01-01

    The purpose of this study was to evaluate how sixth grade children planned, translated, and revised written narrative stories using a task reflecting current instructional and assessment practices. A modified version of the Hayes and Flower (1980) writing process model was used as the theoretical framework for the study. Two hundred one…

  20. Marginal Maximum A Posteriori Item Parameter Estimation for the Generalized Graded Unfolding Model

    Science.gov (United States)

    Roberts, James S.; Thompson, Vanessa M.

    2011-01-01

    A marginal maximum a posteriori (MMAP) procedure was implemented to estimate item parameters in the generalized graded unfolding model (GGUM). Estimates from the MMAP method were compared with those derived from marginal maximum likelihood (MML) and Markov chain Monte Carlo (MCMC) procedures in a recovery simulation that varied sample size,…

  1. Map Resource Packet: Course Models for the History-Social Science Framework, Grade Seven.

    Science.gov (United States)

    California State Dept. of Education, Sacramento.

    This packet of maps is an auxiliary resource to the "World History and Geography: Medieval and Early Modern Times. Course Models for the History-Social Science Framework, Grade Seven." The set includes: outline, precipitation, and elevation maps; maps for locating key places; landform maps; and historical maps. The list of maps are…

  2. Markov Chain Monte Carlo Estimation of Item Parameters for the Generalized Graded Unfolding Model

    Science.gov (United States)

    de la Torre, Jimmy; Stark, Stephen; Chernyshenko, Oleksandr S.

    2006-01-01

    The authors present a Markov Chain Monte Carlo (MCMC) parameter estimation procedure for the generalized graded unfolding model (GGUM) and compare it to the marginal maximum likelihood (MML) approach implemented in the GGUM2000 computer program, using simulated and real personality data. In the simulation study, test length, number of response…

  3. A Structural Equation Model Explaining 8th Grade Students' Mathematics Achievements

    Science.gov (United States)

    Yurt, Eyüp; Sünbül, Ali Murat

    2014-01-01

    The purpose of this study is to investigate, via a model, the explanatory and predictive relationships among the following variables: Mathematical Problem Solving and Reasoning Skills, Sources of Mathematics Self-Efficacy, Spatial Ability, and Mathematics Achievements of Secondary School 8th Grade Students. The sample group of the study, itself…

  4. Model Drawing Strategy for Fraction Word Problem Solving of Fourth-Grade Students with Learning Disabilities

    Science.gov (United States)

    Sharp, Emily; Shih Dennis, Minyi

    2017-01-01

    This study used a multiple probe across participants design to examine the effects of a model drawing strategy (MDS) intervention package on fraction comparing and ordering word problem-solving performance of three Grade 4 students. MDS is a form of cognitive strategy instruction for teaching word problem solving that includes explicit instruction…

  5. Mechanistic PBPK Modeling of the Dissolution and Food Effect of a BCS IV Compound - the Venetoclax Story.

    Science.gov (United States)

    Emami Riedmaier, Arian; Lindley, David J; Hall, Jeffrey A; Castleberry, Steven; Slade, Russell T; Stuart, Patricia; Carr, Robert A; Borchardt, Thomas B; Bow, Daniel A J; Nijsen, Marjoleen

    2017-10-06

    Venetoclax, a selective B-cell lymphoma-2 inhibitor, is a biopharmaceutics classification system (BCS) class IV compound. The aim of this study was to develop a physiologically-based pharmacokinetic (PBPK) model to mechanistically describe absorption and disposition of an amorphous solid dispersion (ASD) formulation of venetoclax in humans. A mechanistic PBPK model was developed incorporating measured amorphous solubility, dissolution, metabolism and plasma protein binding. A middle-out approach was used to define permeability. Model predictions of oral venetoclax pharmacokinetics were verified against clinical studies of fed and fasted healthy volunteers, and clinical drug interaction studies with strong CYP3A inhibitor (ketoconazole) and inducer (rifampicin). Model verification demonstrated accurate prediction of the observed food effect following a low-fat diet. Ratios of predicted versus observed Cmax and AUC of venetoclax were within 0.8- to 1.25-fold of observed ratios for strong CYP3A inhibitor and inducer interactions, indicating that the venetoclax elimination pathway was correctly specified. The verified venetoclax PBPK model is one of the first examples mechanistically capturing absorption, food effect and exposure of an ASD formulated compound. This model allows evaluation of untested drug-drug interactions, especially those primarily occurring in the intestine, and paves the way for future modeling of BCS IV compounds. Copyright © 2017. Published by Elsevier Inc.

  6. Theoretical investigations and density functional theory based quantitative structure-activity relationships model for novel cytotoxic platinum(IV) complexes.

    Science.gov (United States)

    Varbanov, Hristo P; Jakupec, Michael A; Roller, Alexander; Jensen, Frank; Galanski, Markus; Keppler, Bernhard K

    2013-01-10

    Octahedral platinum(IV) complexes are promising candidates in the fight against cancer. In order to rationalize the further development of this class of compounds, detailed studies on their mechanisms of action, toxicity, and resistance must be provided and structure-activity relationships must be drawn. Herein, we report on theoretical and QSAR investigations of a series of 53 novel bis-, tris-, and tetrakis(carboxylato)platinum(IV) complexes, synthesized and tested for cytotoxicity in our laboratories. The hybrid DFT functional wb97x was used for optimization of the structure geometry and calculation of the descriptors. Reliable and robust QSAR models with good explanatory and predictive properties were obtained for both the cisplatin sensitive cell line CH1 and the intrinsically cisplatin resistant cell line SW480, with a set of four descriptors.

  7. Theoretical Investigations and Density Functional Theory Based Quantitative Structure–Activity Relationships Model for Novel Cytotoxic Platinum(IV) Complexes

    Science.gov (United States)

    2012-01-01

    Octahedral platinum(IV) complexes are promising candidates in the fight against cancer. In order to rationalize the further development of this class of compounds, detailed studies on their mechanisms of action, toxicity, and resistance must be provided and structure–activity relationships must be drawn. Herein, we report on theoretical and QSAR investigations of a series of 53 novel bis-, tris-, and tetrakis(carboxylato)platinum(IV) complexes, synthesized and tested for cytotoxicity in our laboratories. The hybrid DFT functional wb97x was used for optimization of the structure geometry and calculation of the descriptors. Reliable and robust QSAR models with good explanatory and predictive properties were obtained for both the cisplatin sensitive cell line CH1 and the intrinsically cisplatin resistant cell line SW480, with a set of four descriptors. PMID:23214999

  8. The experimental chemotherapy of leishmaniasis, IV. The development of a rodent model for visceral infection.

    Science.gov (United States)

    Trotter, E R; Peters, W; Robinson, B L

    1980-04-01

    A description is given of two methods for investigating the action of drugs against a viscerotropic Leishmania in mice. The parasite employed was isolated from a patient with kala-azar in Ethiopia. It is designated 'L. infantum LV9' and produces a visceral infection in NMRI mice. The biochemical typing characters of the parasite are described. In Method A, infected animals were treated from the 5th or 6th day after infection (D + 5 or D + 6) for five consecutive days. They were sacrificed 24 hours after the completion of drug treatment and an estimate was made of the amastigote load in the liver. A comparison of this with untreated controls gives an index of activity of a test drug, from 0 to 3. Method B is similar except that the ED50 and ED90 are determined by graphic analysis of data from graded drug doses. A comparison is made with sodium stibogluconate used as a positive drug control to yield a 'Pentostam Index'. The course of infection in BALB/c and NMRI mice is compared with that in random-bred Swiss mice in which 'L. infantum LV9' produces an inconsistent infection. An inoculum of 10(7) amastigotes produces a peak parasite intensity between D + 15 and D + 20. The ED50 and ED90 of sodium stibogluconate (Pentostam) (as Sbv) in Method B are 22 x 5 and 46 x 5 mg/kg sc daily x 5. (By Method A the single dose figures are 65 and 280 mg/kg.) For routine use a standard dose level of 120 mg/kg sc daily x 5 of Pentostam (Sbv) is used in Method B. The ED50 and ED90 of meglumine antimoniate (Glucantime) (as Sbv) in Method B are 11 x 6 and 66 x 7 mg/kg sc daily x 5. Data are given for other antimonials in Method A. Pentamidine and diminazene aceturate proved to have a slow action which was more readily demonstrated if the observation period was prolonged. Amphotericin B was moderately active but toxic to the host. The relevance of these models and a comparison of data found in the mouse and hamster are debated.

  9. Models of organizational-pedagogical terms of physical education of students of I-IV of courses.

    Directory of Open Access Journals (Sweden)

    Turchina N.I.

    2011-05-01

    Full Text Available The article presents a model of organizational-pedagogical conditions of physical education students I-IV courses and made an analysis of problems of physical education students, which relate to the organization and content of the educational process in relation to problems of professional-applied physical training and motivation for physical perfection of youth. It is proposed the basic requirements for a model of physical education. It is developed a new structure of the Department of Physical Education, which includes its divisions and refined assignments of each structural unit.

  10. Phase Stability under Irradiation of Precipitates and Solid Solutions in Model ALloys and in ODS Alloys Relevant for Gen IV

    Energy Technology Data Exchange (ETDEWEB)

    Arthur T. Motta; Robert C. Birtcher

    2007-10-17

    The overall objective of this program is to investigate the irradiation-altered phase stability of oxide precipitates in ODS steels and of model alloy solid solutions of associated systems. This information can be used to determine whether the favorable mechanical propertiies of these steels are maintained under irradiation, thus addressing one of the main materials research issues for this class of steels as identified by the GenIV working groups. The research program will also create fundamental understanding of the irradiation precipitation/dissolution problem by studying a "model" system in which the variables can be controlled and their effects understood individually.

  11. An AIDS model with distributed incubation and variable infectiousness: applications to i.v. drug users in Latium, Italy.

    Science.gov (United States)

    Iannelli, M; Loro, R; Milner, F; Pugliese, A; Rabbiolo, G

    1992-07-01

    An AIDS model with distributed incubation and variable infectiousness is considered and simulated via a second-order numerical method. The method is applied to the HIV epidemic among IV drug users in the Latium region of Italy, using available data on the length of the incubation period before the onset of AIDS, on the infectivity of infected individuals during that period, and on the demography of drug users. The contact rate is adjusted to match the actual number of AIDS cases. The sensitivity of the model to uncertainties in the parameters is finally investigated, by performing several simulations.

  12. Dipeptidyl peptidase IV in two human glioma cell lines

    Directory of Open Access Journals (Sweden)

    A Sedo

    2009-12-01

    Full Text Available There is growing evidence that dipeptidyl peptidase IV [DPP-IV, EC 3.4.14.5] takes part in the metabolism of biologically active peptides participating in the regulation of growth and transformation of glial cells. However, the knowledge on the DPP-IV expression in human glial and glioma cells is still very limited. In this study, using histochemical and biochemical techniques, the DPP-IV activity was demonstrated in two commercially available human glioma cell lines of different transformation degree, as represented by U373 astrocytoma (Grade III and U87 glioblastoma multiforme (Grade IV lines. Higher total activity of the enzyme, as well as its preferential localisation in the plasma membrane, was observed in U87 cells. Compared to U373 population, U87 cells were morphologically more pleiomorphic, they were cycling at lower rate and expressing less Glial Fibrillary Acidic Protein. The data revealed positive correlation between the degree of transformation of cells and activity of DPP-IV. Great difference in expression of this enzyme, together with the phenotypic differences of cells, makes these lines a suitable standard model for further 57 studies of function of this enzyme in human glioma cells.

  13. Asteroids IV

    Science.gov (United States)

    Michel, Patrick; DeMeo, Francesca E.; Bottke, William F.

    Asteroids are fascinating worlds. Considered the building blocks of our planets, many of the authors of this book have devoted their scientific careers to exploring them with the tools of our trade: ground- and spacebased observations, in situ space missions, and studies that run the gamut from theoretical modeling efforts to laboratory work. Like fossils for paleontologists, or DNA for geneticists, they allow us to construct a veritable time machine and provide us with tantalizing glimpses of the earliest nature of our solar system. By investigating them, we can probe what our home system was like before life or even the planets existed. The origin and evolution of life on our planet is also intertwined with asteroids in a different way. It is believed that impacts on the primordial Earth may have delivered the basic components for life, with biology favoring attributes that could more easily survive the aftermath of such energetic events. In this fashion, asteroids may have banished many probable avenues for life to relative obscurity. Similarly, they may have also prevented our biosphere from becoming more complex until more recent eras. The full tale of asteroid impacts on the history of our world, and how human life managed to emerge from myriad possibilities, has yet to be fully told. The hazard posed by asteroid impacts to our civilization is low but singular. The design of efficient mitigation strategies strongly relies on asteroid detection by our ground- and spacebased surveys as well as knowledge of their physical properties. A more positive motivation for asteroid discovery is that the proximity of some asteroids to Earth may allow future astronauts to harvest their water and rare mineral resources for use in exploration. A key goal of asteroid science is therefore to learn how humans and robotic probes can interact with asteroids (and extract their materials) in an efficient way. We expect that these adventures may be commonplace in the future

  14. Applying a Multiple Group Causal Indicator Modeling Framework to the Reading Comprehension Skills of Third, Seventh, and Tenth Grade Students

    Science.gov (United States)

    Tighe, Elizabeth L.; Wagner, Richard K.; Schatschneider, Christopher

    2015-01-01

    This study demonstrates the utility of applying a causal indicator modeling framework to investigate important predictors of reading comprehension in third, seventh, and tenth grade students. The results indicated that a 4-factor multiple indicator multiple indicator cause (MIMIC) model of reading comprehension provided adequate fit at each grade level. This model included latent predictor constructs of decoding, verbal reasoning, nonverbal reasoning, and working memory and accounted for a large portion of the reading comprehension variance (73% to 87%) across grade levels. Verbal reasoning contributed the most unique variance to reading comprehension at all grade levels. In addition, we fit a multiple group 4-factor MIMIC model to investigate the relative stability (or variability) of the predictor contributions to reading comprehension across development (i.e., grade levels). The results revealed that the contributions of verbal reasoning, nonverbal reasoning, and working memory to reading comprehension were stable across the three grade levels. Decoding was the only predictor that could not be constrained to be equal across grade levels. The contribution of decoding skills to reading comprehension was higher in third grade and then remained relatively stable between seventh and tenth grade. These findings illustrate the feasibility of using MIMIC models to explain individual differences in reading comprehension across the development of reading skills. PMID:25821346

  15. Exploring Third-Grade Student Model-Based Explanations about Plant Relationships within an Ecosystem

    Science.gov (United States)

    Zangori, Laura; Forbes, Cory T.

    2015-12-01

    Elementary students should have opportunities to develop scientific models to reason and build understanding about how and why plants depend on relationships within an ecosystem for growth and survival. However, scientific modeling practices are rarely included within elementary science learning environments and disciplinary content is often treated as discrete pieces separate from scientific practice. Elementary students have few, if any, opportunities to reason about how individual organisms, such as plants, hold critical relationships with their surrounding environment. The purpose of this design-based research study is to build a learning performance to identify and explore the third-grade students' baseline understanding of and their reasoning about plant-ecosystem relationships when engaged in the practices of modeling. The developed learning performance integrated scientific content and core scientific activity to identify and measure how students build knowledge about the role of plants in ecosystems through the practices of modeling. Our findings indicate that the third-grade students' ideas about plant growth include abiotic and biotic relationships. Further, they used their models to reason about how and why these relationships were necessary to maintain plant stasis. However, while the majority of the third-grade students were able to identify and reason about plant-abiotic relationships, a much smaller group reasoned about plant-abiotic-animal relationships. Implications from the study suggest that modeling serves as a tool to support elementary students in reasoning about system relationships, but they require greater curricular and instructional support in conceptualizing how and why ecosystem relationships are necessary for plant growth and development. This paper is based on data from a doctoral dissertation. An earlier version of this paper was presented at the 2015 international conference for the National Association for Research in Science

  16. Carbonatites of the World, Explored Deposits of Nb and REE - Database and Grade and Tonnage Models

    Science.gov (United States)

    Berger, Vladimir I.; Singer, Donald A.; Orris, Greta J.

    2009-01-01

    This report is based on published tonnage and grade data on 58 Nb- and rare-earth-element (REE)-bearing carbonatite deposits that are mostly well explored and are partially mined or contain resources of these elements. The deposits represent only a part of the known 527 carbonatites around the world, but they are characterized by reliable quantitative data on ore tonnages and grades of niobium and REE. Grade and tonnage models are an important component of mineral resource assessments. Carbonatites present one of the main natural sources of niobium and rare-earth elements, the economic importance of which grows consistently. A purpose of this report is to update earlier publications. New information about known deposits, as well as data on new deposits published during the last decade, are incorporated in the present paper. The compiled database (appendix 1; linked to right) contains 60 explored Nb- and REE-bearing carbonatite deposits - resources of 55 of these deposits are taken from publications. In the present updated grade-tonnage model we have added 24 deposits comparing with the previous model of Singer (1998). Resources of most deposits are residuum ores in the upper part of carbonatite bodies. Mineral-deposit models are important in exploration planning and quantitative resource assessments for two reasons: (1) grades and tonnages among deposit types vary significantly, and (2) deposits of different types are present in distinct geologic settings that can be identified from geologic maps. Mineral-deposit models combine the diverse geoscience information on geology, mineral occurrences, geophysics, and geochemistry used in resource assessments and mineral exploration. Globally based deposit models allow recognition of important features and demonstrate how common different features are. Well-designed deposit models allow geologists to deduce possible mineral-deposit types in a given geologic environment, and the grade and tonnage models allow economists to

  17. Assessment of a model for achieving competency in administration and scoring of the WAIS-IV in post-graduate psychology students

    National Research Council Canada - National Science Library

    Roberts, Rachel M; Davis, Melissa C

    2015-01-01

    .... Twenty three post-graduate psychology students underwent training in using the WAIS-IV according to a best-practice teaching model that involved didactic teaching, independent study of the test...

  18. Molecular interaction fields vs. quantum-mechanical-based descriptors in the modelling of lipophilicity of platinum(IV) complexes.

    Science.gov (United States)

    Ermondi, Giuseppe; Caron, Giulia; Ravera, Mauro; Gabano, Elisabetta; Bianco, Sabrina; Platts, James A; Osella, Domenico

    2013-03-14

    We report QSAR calculations using VolSurf descriptors to model the lipophilicity of 53 Pt(iv) complexes with a diverse range of axial and equatorial ligands. Lipophilicity is measured using an efficient HPLC method. Previous models based on a subset of these data are shown to be inadequate, due to incompatibility of whole molecule descriptors between carboxylato and hydroxido ligands. Instead, the interaction surfaces of complexes with various probes are used as independent descriptors. Partial least squares modelling using three latent variables results in an accurate (R(2) = 0.92) and robust model (Q(2) = 0.87) of lipophilicity, that moreover highlights the importance of size and hydrophobicity terms and the modest relevance of hydrogen bonding.

  19. Recovery of a human natural antibody against the noncollagenous-1 domain of type IV collagen using humanized models.

    Science.gov (United States)

    Worni-Schudel, Inge M; Clark, Amy G; Chien, Tiffany; Hwang, Kwan-Ki; Chen, Benny J; Foster, Mary H

    2015-06-06

    Anti-glomerular basement membrane nephritis and Goodpasture syndrome result from autoantibody (Ab)-mediated destruction of kidney and lung. Ab target the noncollagenous 1 (NC1) domain of alpha3(IV) collagen, but little is known about Ab origins or structure. This ignorance is due in part to the inability to recover monoclonal Ab by transformation of patients' blood cells. The aim of this study was to assess the suitability of two humanized models for this purpose. NOD-scid-gamma immunodeficient mice were engrafted either with human CD34+ hematopoietic stem cells (HSC) (Hu-HSC mice) and immunized with alpha3(IV)NC1 collagen containing the Goodpasture epitopes or with nephritis patients' peripheral blood leukocytes (PBL) (Hu-PBL mice). After in vivo immune cell development and/or expansion, recovered human B cells were Epstein Barr virus (EBV)-transformed, screened for antigen (Ag) binding, electrofused with a mouse-human heterohybridoma, subcloned, and human Ab RNA sequenced by PCR after reverse transcription to cDNA. Flow cytometry was used to assess human B cell markers and differentiation in Hu-PBL mice. Sequence analysis of a human Ab derived from an immunized Hu-HSC mouse and reactive with alpha3(IV)NC1 collagen reveals that it is encoded by unmutated heavy and light chain genes. The heavy chain complementarity determining region 3, a major determinant of Ag binding, contains uncommon motifs, including an N-region somatically-introduced highly hydrophobic tetrapeptide and dual cysteines encoded by a uniquely human IGHD2-2 Ab gene segment that lacks a murine counterpart. Comparison of human and mouse autoantibodies suggests that structurally similar murine Ab may arise by convergent selection. In contrast to the Hu-HSC model, transformed human B cells are rarely recovered from Hu-PBL mice, in which human B cells terminally differentiate and lose expression of EBV receptor CD21, thus precluding their transformation and recovery. Hu-HSC mice reveal that

  20. Long-term occlusal changes assessed by the American Board of Orthodontics' model grading system.

    Science.gov (United States)

    Aszkler, Robert M; Preston, Charles B; Saltaji, Humam; Tabbaa, Sawsan

    2014-02-01

    The purpose of this study was to assess the long-term posttreatment changes in all criteria of the American Board of Orthodontics' (ABO) model grading system. We used plaster models from patients' final and posttreatment records. Thirty patients treated by 1 orthodontist using 1 bracket prescription were selected. An initial discrepancy index for each subject was performed to determine the complexity of each case. The final models were then graded using the ABO's model grading system immediately at posttreatment and postretention. Statistical analysis was performed on the 8 criteria of the model grading system, including paired t tests and Pearson correlations. An alpha of 0.05 was considered statistically significant. The average length of time between the posttreatment and postretention records was 12.7 ± 4.4 years. It was shown that alignment and rotations worsened by postretention (P = 0.014), and a weak statistically significant correlation at posttreatment and postretention was found (0.44; P = 0.016). Both marginal ridges and occlusal contacts scored less well at posttreatment. These criteria showed a significant decrease in scores between posttreatment and postretention (P <0.001), but the correlations were not statistically significant. The average total score showed a significant decrease between posttreatment and postretention (P <0.001), partly because of the large decrease in the previous 2 criteria. Higher scores for occlusal contacts and marginal ridges were found at the end of treatment; however, those scores and the overall scores for the 30 subjects improved in the postretention phase. Copyright © 2014. Published by Mosby, Inc.

  1. Multiaxial Creep-Fatigue and Creep-Ratcheting Failures of Grade 91 and Haynes 230 Alloys Toward Addressing Design Issues of Gen IV Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Hassan, Tasnim [North Carolina State Univ., Raleigh, NC (United States); Lissenden, Cliff [Penn State Univ., University Park, PA (United States); Carroll, Laura [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-04-01

    The proposed research will develop systematic sets of uniaxial and multiaxial experimental data at a very high temperature (850-950°C) for Alloy 617. The loading histories to be prescribed in the experiments will induce creep-fatigue and creep-ratcheting failure mechanisms. These experimental responses will be scrutinized in order to quantify the influences of temperature and creep on fatigue and ratcheting failures. A unified constitutive model (UCM) will be developed and validated against these experimental responses. The improved UCM will be incorporated into the widely used finite element commercial software packages ANSYS. The modified ANSYS will be validated so that it can be used for evaluating the very high temperature ASME-NH design-by-analysis methodology for Alloy 617 and thereby addressing the ASME-NH design code issues.

  2. The Nature and Role of Physical Models in Enhancing Sixth Grade Students' Mental Models of Groundwater and Groundwater Processes

    Science.gov (United States)

    Duffy, Debra Lynne Foster

    2012-01-01

    Through a non-experimental descriptive and comparative mixed-methods approach, this study investigated the experiences of sixth grade earth science students with groundwater physical models through an extended SE learning cycle format. The data collection was based on a series of quantitative and qualitative research tools intended to investigate…

  3. The Nature and Role of Physical Models in Enhancing Sixth Grade Students' Mental Models of Groundwater and Groundwater Processes

    Science.gov (United States)

    Duffy, Debra Lynne Foster

    2012-01-01

    Through a non-experimental descriptive and comparative mixed-methods approach, this study investigated the experiences of sixth grade earth science students with groundwater physical models through an extended SE learning cycle format. The data collection was based on a series of quantitative and qualitative research tools intended to investigate…

  4. Three-Dimensional Finite Element Modeling of Thermomechanical Problems in Functionally Graded Hydroxyapatite/Titanium Plate

    Directory of Open Access Journals (Sweden)

    S. N. S. Jamaludin

    2014-01-01

    Full Text Available The composition of hydroxyapatite (HA as the ceramic phase and titanium (Ti as the metallic phase in HA/Ti functionally graded materials (FGMs shows an excellent combination of high biocompatibility and high mechanical properties in a structure. Because the gradation of these properties is one of the factors that affects the response of the functionally graded (FG plates, this paper is presented to show the domination of the grading parameter on the displacement and stress distribution of the plates. A three-dimensional (3D thermomechanical model of a 20-node brick quadratic element is used in the simulation of the thermoelastic behaviors of HA/Ti FG plates subjected to constant and functional thermal, mechanical, and thermomechanical loadings. The convergence properties of the present results are examined thoroughly in order to assess the accuracy of the theory applied and to compare them with the established research results. Instead of the grading parameter, this study reveals that the loading field distribution can be another factor that reflects the thermoelastic properties of the HA/Ti FG plates. The FG structure is found to be able to withstand the thermal stresses while preserving the high toughness properties and thus shows its ability to operate at high temperature.

  5. Academic self-concept, interest, grades, and standardized test scores: reciprocal effects models of causal ordering.

    Science.gov (United States)

    Marsh, Herbert W; Trautwein, Ulrich; Lüdtke, Oliver; Köller, Olaf; Baumert, Jürgen

    2005-01-01

    Reciprocal effects models of longitudinal data show that academic self-concept is both a cause and an effect of achievement. In this study this model was extended to juxtapose self-concept with academic interest. Based on longitudinal data from 2 nationally representative samples of German 7th-grade students (Study 1: N = 5,649, M age = 13.4; Study 2: N = 2,264, M age = 13.7 years), prior self-concept significantly affected subsequent math interest, school grades, and standardized test scores, whereas prior math interest had only a small effect on subsequent math self-concept. Despite stereotypic gender differences in means, linkages relating these constructs were invariant over gender. These results demonstrate the positive effects of academic self-concept on a variety of academic outcomes and integrate self-concept with the developmental motivation literature.

  6. Modelling Thermal Shock in Functionally Graded Plates with Finite Element Method

    Directory of Open Access Journals (Sweden)

    Vyacheslav N. Burlayenko

    2016-01-01

    Full Text Available Thermomechanical behavior and crack propagation in a functionally graded metal/ceramic plate undergoing thermal shock are analyzed by using the finite element method. A two-dimensional plane strain functionally graded finite element has been developed within the ABAQUS software environment for this purpose. An actual material gradation has been accomplished by sampling material quantities directly at the Gauss points of the element via programming appropriate user-defined subroutines. The virtual crack closure technique is used to model a crack growth under thermal loading. Contact possible between crack lips during the crack advance is taken into account in thermomechanical simulations as well. The paper shows that the presented finite element model can be applied to provide an insight into the thermomechanical respond and failure of the metal/ceramic plate.

  7. Comparative studies of oxaliplatin-based platinum(iv) complexes in different in vitro and in vivo tumor models.

    Science.gov (United States)

    Göschl, Simone; Schreiber-Brynzak, Ekaterina; Pichler, Verena; Cseh, Klaudia; Heffeter, Petra; Jungwirth, Ute; Jakupec, Michael A; Berger, Walter; Keppler, Bernhard K

    2017-03-22

    Using platinum(iv) prodrugs of clinically established platinum(ii) compounds is a strategy to overcome side effects and acquired resistances. We studied four oxaliplatin-derived platinum(iv) complexes with varying axial ligands in various in vitro and in vivo settings. The ability to interfere with DNA (pUC19) in the presence and absence of a reducing agent (ascorbic acid) was investigated in cell-free experiments. Cytotoxicity was compared under normoxic and hypoxic conditions in monolayer cultures and multicellular spheroids of colon carcinoma cell lines. Effects on the cell cycle were investigated by flow cytometry, and the capacity of inducing apoptosis was confirmed by flow cytometry and Western blotting. The anti-cancer activity of one complex was studied in vivo in immunodeficient and immunocompetent mice, and the platinum levels in various organs and the tumor after treatment were quantified. The results demonstrate that modification of the axial ligands can improve the cytotoxic potency. The complexes are able to interfere with plasmid DNA, which is enhanced by co-incubation with a reducing agent, and cause cell cycle perturbations. At higher concentrations, they induce apoptosis, but generate only low levels of reactive oxygen species. Two of the complexes increase the life span of leukemia (L1210) bearing mice, and one showed effects similar to oxaliplatin in a CT26 solid tumor model, despite the low platinum levels in the tumor. As in the case of oxaliplatin, activity in the latter model depends on an intact immune system. These findings show new perspectives for the development of platinum(iv) prodrugs of the anticancer agent oxaliplatin, combining bioreductive properties and immunogenic aspects.

  8. Flat Currents and Solutions of Sigma Model on Supercoset Targets with Z2m Grading

    Institute of Scientific and Technical Information of China (English)

    KE san-Min; SHI Kang-Jie; WANG Chun; WU Sheng

    2007-01-01

    We find one parameter flat currents of the sigma model on supercoset targets with Z2m grading given by Young satisfaction equations of motion and the Virasoro constraint.This meads that one can generate a series of classical solutions from the original one.For these new solutions one can also construct flat currents and conserved charges,which form the same set with the original one.

  9. Branch structure of IV-characteristics in the capacitively coupled Josephson junctions model with the diffusion current

    Energy Technology Data Exchange (ETDEWEB)

    Shukrinov, Yu.M. [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Physical Technical Institute, Dushanbe 734063 (Tajikistan)], E-mail: shukrinv@theor.jinr.ru; Mahfouzi, F. [Institute for Advanced Studies in Basic Sciences, P.O. Box 45195-1159, Zanjan (Iran, Islamic Republic of); Seidel, P. [Institut fuer Festkorperphysik, Friedrich-Schiller-Universitaet Jena, D-07743 Jena (Germany)

    2007-09-01

    We have solved numerically a system of dynamical equations for the gauge-invariant phase differences between superconducting layers for a stack of N intrinsic junctions and obtained a total branch structure in the current-voltage characteristics (IVC) of the stack. The coupling dependence of the branch's slopes is investigated and demonstrated that the equidistance of the branch structure in capacitively coupled Josephson junctions (CCJJ) model is broken at small values of coupling parameter. Changes in the parameters of the boundary conditions and the use of periodic boundary conditions do not affect this result. In the framework of the CCJJ model with the diffusion current we simulate an experiment and obtain the IV-characteristic with equidistant branch structure at different values of model parameters.

  10. Branch structure of IV-characteristics in the capacitively coupled Josephson junctions model with the diffusion current

    Science.gov (United States)

    Shukrinov, Yu. M.; Mahfouzi, F.; Seidel, P.

    2007-09-01

    We have solved numerically a system of dynamical equations for the gauge-invariant phase differences between superconducting layers for a stack of N intrinsic junctions and obtained a total branch structure in the current-voltage characteristics (IVC) of the stack. The coupling dependence of the branch’s slopes is investigated and demonstrated that the equidistance of the branch structure in capacitively coupled Josephson junctions (CCJJ) model is broken at small values of coupling parameter. Changes in the parameters of the boundary conditions and the use of periodic boundary conditions do not affect this result. In the framework of the CCJJ model with the diffusion current we simulate an experiment and obtain the IV-characteristic with equidistant branch structure at different values of model parameters.

  11. Multiscale Modeling of Structurally-Graded Materials Using Discrete Dislocation Plasticity Models and Continuum Crystal Plasticity Models

    Science.gov (United States)

    Saether, Erik; Hochhalter, Jacob D.; Glaessgen, Edward H.

    2012-01-01

    A multiscale modeling methodology that combines the predictive capability of discrete dislocation plasticity and the computational efficiency of continuum crystal plasticity is developed. Single crystal configurations of different grain sizes modeled with periodic boundary conditions are analyzed using discrete dislocation plasticity (DD) to obtain grain size-dependent stress-strain predictions. These relationships are mapped into crystal plasticity parameters to develop a multiscale DD/CP model for continuum level simulations. A polycrystal model of a structurally-graded microstructure is developed, analyzed and used as a benchmark for comparison between the multiscale DD/CP model and the DD predictions. The multiscale DD/CP model follows the DD predictions closely up to an initial peak stress and then follows a strain hardening path that is parallel but somewhat offset from the DD predictions. The difference is believed to be from a combination of the strain rate in the DD simulation and the inability of the DD/CP model to represent non-monotonic material response.

  12. In situ characterization of cofacial Co(IV) centers in Co4O4 cubane: Modeling the high-valent active site in oxygen-evolving catalysts.

    Science.gov (United States)

    Brodsky, Casey N; Hadt, Ryan G; Hayes, Dugan; Reinhart, Benjamin J; Li, Nancy; Chen, Lin X; Nocera, Daniel G

    2017-03-27

    The Co4O4 cubane is a representative structural model of oxidic cobalt oxygen-evolving catalysts (Co-OECs). The Co-OECs are active when residing at two oxidation levels above an all-Co(III) resting state. This doubly oxidized Co(IV)2 state may be captured in a Co(III)2(IV)2 cubane. We demonstrate that the Co(III)2(IV)2 cubane may be electrochemically generated and the electronic properties of this unique high-valent state may be probed by in situ spectroscopy. Intervalence charge-transfer (IVCT) bands in the near-IR are observed for the Co(III)2(IV)2 cubane, and spectroscopic analysis together with electrochemical kinetics measurements reveal a larger reorganization energy and a smaller electron transfer rate constant for the doubly versus singly oxidized cubane. Spectroelectrochemical X-ray absorption data further reveal systematic spectral changes with successive oxidations from the cubane resting state. Electronic structure calculations correlated to experimental data suggest that this state is best represented as a localized, antiferromagnetically coupled Co(IV)2 dimer. The exchange coupling in the cofacial Co(IV)2 site allows for parallels to be drawn between the electronic structure of the Co4O4 cubane model system and the high-valent active site of the Co-OEC, with specific emphasis on the manifestation of a doubly oxidized Co(IV)2 center on O-O bond formation.

  13. The structure of personality disorders: comparing the DSM-IV-TR Axis II classification with the five-factor model framework using structural equation modeling.

    Science.gov (United States)

    Bastiaansen, Leen; Rossi, Gina; Schotte, Christiaan; De Fruyt, Filip

    2011-06-01

    Earlier factor analytical studies on the empirical validity of the DSM-IV-TR (American Psychological Association, 2000) Axis II classification have offered little support for the current three-cluster structure. In his large-scale meta-analysis of previously published personality disorder correlation matrices, O'Connor (2005) found four factors, corresponding to the neuroticism, extraversion, agreeableness, and conscientiousness domains of the five-factor model of personality. In the present study, this dimensional four-factor model and the categorical DSM three-cluster structure were fitted to the Assessment of DSM-IV Personality Disorders questionnaire (ADP-IV; Schotte & De Doncker, 1994) scale scores using structural equation modelling. The results strongly favored the dimensional model, which also resembled other well-founded four-factor proposals (Livesley, Jang, & Vernon, 1998; Widiger & Simonsen, 2005). Moreover, a multigroup confirmatory factor analysis showed that this model was highly invariant and thus generalizable across two large clinical (n = 1,029) and general population (n = 659) samples.

  14. ON THE USE OF NEXRAD STAGE IV DATA IN THE MULTIMEDIA MODELING OF POLLUTANT TRANSPORT

    Science.gov (United States)

    The Environmental Protection Agency (EPA) is designing the Multimedia Integrated Modeling System (MIMS) to model the cycling of pollutants and nutrients between the atmosphere and the earth's surface, including water bodies and groundwater. Our ability to accurately model both ...

  15. Using a Bifactor Model to Assess the Factor Structure of the Phonological Awareness Literacy Screening for Grades 1 through 3

    Science.gov (United States)

    Huang, Francis L.

    2014-01-01

    The factor structure of the Phonological Awareness Literacy Screening for Grades 1 through 3 (PALS 1-3), a widely used early literacy screener in the Commonwealth of Virginia, was investigated using a large sample of public-school second-grade students (n = 14,993). Three alternative factor models (i.e., a one-factor, two-correlated factors, and a…

  16. An accurate higher order displacement model with shear and normal deformations effects for functionally graded plates

    Energy Technology Data Exchange (ETDEWEB)

    Jha, D.K., E-mail: dkjha@barc.gov.in [Civil Engineering Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India); Kant, Tarun [Department of Civil Engineering, Indian Institute of Technology Bombay, Powai, Mumbai 400 076 (India); Srinivas, K. [Civil Engineering Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Singh, R.K. [Reactor Safety Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India)

    2013-12-15

    Highlights: • We model through-thickness variation of material properties in functionally graded (FG) plates. • Effect of material grading index on deformations, stresses and natural frequency of FG plates is studied. • Effect of higher order terms in displacement models is studied for plate statics. • The benchmark solutions for the static analysis and free vibration of thick FG plates are presented. -- Abstract: Functionally graded materials (FGMs) are the potential candidates under consideration for designing the first wall of fusion reactors with a view to make best use of potential properties of available materials under severe thermo-mechanical loading conditions. A higher order shear and normal deformations plate theory is employed for stress and free vibration analyses of functionally graded (FG) elastic, rectangular, and simply (diaphragm) supported plates. Although FGMs are highly heterogeneous in nature, they are generally idealized as continua with mechanical properties changing smoothly with respect to spatial coordinates. The material properties of FG plates are assumed here to vary through thickness of plate in a continuous manner. Young's modulii and material densities are considered to be varying continuously in thickness direction according to volume fraction of constituents which are mathematically modeled here as exponential and power law functions. The effects of variation of material properties in terms of material gradation index on deformations, stresses and natural frequency of FG plates are investigated. The accuracy of present numerical solutions has been established with respect to exact three-dimensional (3D) elasticity solutions and the other models’ solutions available in literature.

  17. Impaired myelination and reduced brain ferric iron in the mouse model of mucolipidosis IV.

    Science.gov (United States)

    Grishchuk, Yulia; Peña, Karina A; Coblentz, Jessica; King, Victoria E; Humphrey, Daniel M; Wang, Shirley L; Kiselyov, Kirill I; Slaugenhaupt, Susan A

    2015-12-01

    Mucolipidosis type IV (MLIV) is a lysosomal storage disease caused by mutations in the MCOLN1 gene, which encodes the lysosomal transient receptor potential ion channel mucolipin-1 (TRPML1). MLIV causes impaired motor and cognitive development, progressive loss of vision and gastric achlorhydria. How loss of TRPML1 leads to severe psychomotor retardation is currently unknown, and there is no therapy for MLIV. White matter abnormalities and a hypoplastic corpus callosum are the major hallmarks of MLIV brain pathology. Here, we report that loss of TRPML1 in mice results in developmental aberrations of brain myelination as a result of deficient maturation and loss of oligodendrocytes. Defective myelination is evident in Mcoln1(-/-) mice at postnatal day 10, an active stage of postnatal myelination in the mouse brain. Expression of mature oligodendrocyte markers is reduced in Mcoln1(-/-) mice at postnatal day 10 and remains lower throughout the course of the disease. We observed reduced Perls' staining in Mcoln1(-/-) brain, indicating lower levels of ferric iron. Total iron content in unperfused brain is not significantly different between Mcoln1(-/-) and wild-type littermate mice, suggesting that the observed maturation delay or loss of oligodendrocytes might be caused by impaired iron handling, rather than by global iron deficiency. Overall, these data emphasize a developmental rather than a degenerative disease course in MLIV, and suggest that there should be a stronger focus on oligodendrocyte maturation and survival to better understand MLIV pathogenesis and aid treatment development.

  18. Constitutive Model Of Graded Micro-Structure Obtained Via Strain Induced Phase Transformation

    CERN Document Server

    Ortwein, Rafał

    The literature review has been divided into three main sub-chapters. The first one is concentrated on the general information about stainless steels and their applications. It is important to perform a general overview and get an idea where the results of the present thesis could be applied. Description of all the brands of stainless steels, their microstructures and properties are important, as similar characteristics can be found in the newly created functionally graded structures. The second sub-chapter is an overview of the most important constitutive models and the experimental results for materials that undergo plastic strain induced phase transformation. Finally, the last one is devoted to functionally graded microstructures obtained via strain induced martensitic transformation – the subject of particular importance for the present thesis. As a general note, the literature review is organized mainly in a chronological order. In some cases similar publications or publications of the same Authors were...

  19. MODELLING THE INHIBITORY ACTIVITY ON CARBONIC ANHYDRASE IV OF SUBSTITUTED THIADIAZOLE - AND THIADIAZOLINE - DISULFONAMIDES: INTEGRATION OF STRUCTURE INFORMATION

    Directory of Open Access Journals (Sweden)

    Sorana Daniela Bolboaca

    2006-07-01

    Full Text Available ABSTRACT:Purpose: To analyze the relationships between inhibitory activities on carbonic anhydrase IV and structures of substituted 1,3,4-thiadiazole and 1,3,4-thiadiazoline disulfonamide through integration of compounds complex structure information by the use of Molecular Descriptors Family.Method: A number of forty compounds were used to generate and compute the molecular descriptors family and to build structure-activity relationships models. The obtained multi-varied models (the models with two, respectively with four descriptors were validated by computing the cross-validation leave-one-out score (r2cv-loo, and analyzed through assessment of the squared correlation coefficients (r2, and the models stability (r2 - r2cv-loo. The estimation abilities of the multi-varied MDF-SAR model with four descriptors were analyzed in training and test sets.Results: Analysis of the obtained models shows that the best results was obtained by the multi-varied model with four molecular descriptors (r2 = 0.920. The prediction abilities of this model is sustained by the cross validation leave-one-out score (r2cv-loo = 0.903, the model stability (r2 - r2cv-loo = 0.017, and the results on training versus test analysis (no significant differences between correlation coefficients in training and test sets, p > 0.05. The multi-varied model which used four descriptors proved to render higher value of correlation coefficient comparing with previous reported models (p 0.05. El modelo multivariante que utilizó cuatro descriptores mostró un valor más alto del coeficiente de correlación en comparación con los modelos divulgados anteriormente (p < 0.01.Conclusión: El modelo multivariante con cuatro descriptores es sólido y fiable e indica que la actividad de la inhibición en la carboanhidrasa IV producida por las sufonamidas sustituidas del 1,3,4-tiadiazol- y de la 1,3,4-tiadiazolina- dependen de la naturaleza de la geometría y de la topología del compuesto

  20. Impaired myelination and reduced brain ferric iron in the mouse model of mucolipidosis IV

    Directory of Open Access Journals (Sweden)

    Yulia Grishchuk

    2015-12-01

    Full Text Available Mucolipidosis type IV (MLIV is a lysosomal storage disease caused by mutations in the MCOLN1 gene, which encodes the lysosomal transient receptor potential ion channel mucolipin-1 (TRPML1. MLIV causes impaired motor and cognitive development, progressive loss of vision and gastric achlorhydria. How loss of TRPML1 leads to severe psychomotor retardation is currently unknown, and there is no therapy for MLIV. White matter abnormalities and a hypoplastic corpus callosum are the major hallmarks of MLIV brain pathology. Here, we report that loss of TRPML1 in mice results in developmental aberrations of brain myelination as a result of deficient maturation and loss of oligodendrocytes. Defective myelination is evident in Mcoln1−/− mice at postnatal day 10, an active stage of postnatal myelination in the mouse brain. Expression of mature oligodendrocyte markers is reduced in Mcoln1−/− mice at postnatal day 10 and remains lower throughout the course of the disease. We observed reduced Perls' staining in Mcoln1−/− brain, indicating lower levels of ferric iron. Total iron content in unperfused brain is not significantly different between Mcoln1−/− and wild-type littermate mice, suggesting that the observed maturation delay or loss of oligodendrocytes might be caused by impaired iron handling, rather than by global iron deficiency. Overall, these data emphasize a developmental rather than a degenerative disease course in MLIV, and suggest that there should be a stronger focus on oligodendrocyte maturation and survival to better understand MLIV pathogenesis and aid treatment development.

  1. Clinician judgments of clinical utility: A comparison of DSM-IV-TR personality disorders and the alternative model for DSM-5 personality disorders.

    Science.gov (United States)

    Morey, Leslie C; Skodol, Andrew E; Oldham, John M

    2014-05-01

    This study compared the perceived clinical utility of DSM-IV-TR personality disorder diagnoses (retained in DSM-5) with the alternative model presented in DSM-5 Section III, using a national sample of clinicians applying both systems to their own patients. A sample of 337 mental health clinicians (26% psychiatrists, 63% psychologists, and 11% other professional disciplines) provided a complete assessment of all personality disorder features listed in DSM-IV-TR and DSM-5 Section III. After applying each diagnostic model, clinicians evaluated the clinical utility of that model with respect to communication with patients and with other professionals, comprehensiveness, descriptiveness, ease of use, and utility for treatment planning. These perceptions were compared across DSM-IV-TR and the 3 components of the DSM-5 Section III model, and between psychiatrists and nonpsychiatrists. Although DSM-IV-TR was seen as easy to use and useful for professional communication, in every other respect the DSM-5 Section III model was viewed as being equally or more clinically useful than DSM-IV-TR. In particular, the DSM-5 dimensional trait model was seen as more useful than DSM-IV-TR in 5 of 6 comparisons-by psychiatrists as well as other professionals. Although concerns were expressed about the clinical utility of the DSM-5 personality disorder system during its development, these criticisms were offered without data on the proposed system. The results of this study demonstrate that aside from the current familiarity of the DSM-IV-TR approach, it offers little advantage in perceived clinical utility over the DSM-5 Section III system, whereas the latter is viewed as being more useful in several respects.

  2. Space physiology IV: mathematical modeling of the cardiovascular system in space exploration.

    Science.gov (United States)

    Keith Sharp, M; Batzel, Jerry Joseph; Montani, Jean-Pierre

    2013-08-01

    Mathematical modeling represents an important tool for analyzing cardiovascular function during spaceflight. This review describes how modeling of the cardiovascular system can contribute to space life science research and illustrates this process via modeling efforts to study postflight orthostatic intolerance (POI), a key issue for spaceflight. Examining this application also provides a context for considering broader applications of modeling techniques to the challenges of bioastronautics. POI, which affects a large fraction of astronauts in stand tests upon return to Earth, presents as dizziness, fainting and other symptoms, which can diminish crew performance and cause safety hazards. POI on the Moon or Mars could be more critical. In the field of bioastronautics, POI has been the dominant application of cardiovascular modeling for more than a decade, and a number of mechanisms for POI have been investigated. Modeling approaches include computational models with a range of incorporated factors and hemodynamic sophistication, and also physical models tested in parabolic and orbital flight. Mathematical methods such as parameter sensitivity analysis can help identify key system mechanisms. In the case of POI, this could lead to more effective countermeasures. Validation is a persistent issue in modeling efforts, and key considerations and needs for experimental data to synergistically improve understanding of cardiovascular responses are outlined. Future directions in cardiovascular modeling include subject-specific assessment of system status, as well as research on integrated physiological responses, leading, for instance, to assessment of subject-specific susceptibility to POI or effects of cardiovascular alterations on muscular, vision and cognitive function.

  3. Mathematical Model of a pH-gradient Creation at Isoelectrofocusing. Part IV. Theory

    CERN Document Server

    Shiryaeva, E V; Zhukov, M Yu

    2013-01-01

    The mathematical model describing the non-stationary natural pH-gradient arising under the action of an electric field in an aqueous solution of ampholytes (amino acids) is constructed. The model is a part of a more general model of the isoelectrofocusing (IEF) process. The presented model takes into account: 1) general Ohm's law (electric current flux includes the diffusive electric current); 2) dissociation of water; 3) difference between isoelectric point (IEP) and isoionic point (PZC -- point of zero charge). We also study the Kohlraush's function evolution and discuss the role of the Poisson-Boltzmann equation.

  4. High-grade serous ovarian cancer arises from fallopian tube in a mouse model

    Science.gov (United States)

    Kim, Jaeyeon; Coffey, Donna M.; Creighton, Chad J.; Yu, Zhifeng; Hawkins, Shannon M.; Matzuk, Martin M.

    2012-01-01

    Although ovarian cancer is the most lethal gynecologic malignancy in women, little is known about how the cancer initiates and metastasizes. In the last decade, new evidence has challenged the dogma that the ovary is the main source of this cancer. The fallopian tube has been proposed instead as the primary origin of high-grade serous ovarian cancer, the subtype causing 70% of ovarian cancer deaths. By conditionally deleting Dicer, an essential gene for microRNA synthesis, and Pten, a key negative regulator of the PI3K pathway, we show that high-grade serous carcinomas arise from the fallopian tube in mice. In these Dicer-Pten double-knockout mice, primary fallopian tube tumors spread to engulf the ovary and then aggressively metastasize throughout the abdominal cavity, causing ascites and killing 100% of the mice by 13 mo. Besides the clinical resemblance to human serous cancers, these fallopian tube cancers highly express genes that are known to be up-regulated in human serous ovarian cancers, also demonstrating molecular similarities. Although ovariectomized mice continue to develop high-grade serous cancers, removal of the fallopian tube at an early age prevents cancer formation—confirming the fallopian tube origin of the cancer. Intriguingly, the primary carcinomas are first observed in the stroma of the fallopian tube, suggesting that these epithelial cancers have a mesenchymal origin. Thus, this mouse model demonstrates a paradigm for the origin and initiation of high-grade serous ovarian carcinomas, the most common and deadliest ovarian cancer. PMID:22331912

  5. Kinetic modeling of multi‐component crystallization of industrial‐grade oils and fats

    DEFF Research Database (Denmark)

    Hjorth, Jeppe L.; Miller, Rasmus L.; Woodley, John M.;

    2015-01-01

    Transient crystallization kinetics is investigated for complex, industrial‐grade vegetable oils consisting of more than ten triacylglycerols (TAG). The classical nucleation model has been used to describe primary nucleation, while secondary nucleation has been described by a semi‐empirical approach...... describe how higher cooling rates lead to formation of more meta‐stable crystals and smaller mean‐crystal sizes. : The model provides a good starting point for developing more realistic, transient models for TAG crystallization with the ability to accommodate processing conditions and complex chemical......‐fat content (SFC) measurements for a given oil at different cooling rates and degrees of dilution. The developed model can accommodate more polymorphs simultaneously and performs well with respect to predicting crystallization onset, rate of crystallization and final SFC value. It can also qualitatively...

  6. An exactly solvable model for Brownian motion : IV. Susceptibility and Nyquist's theorem

    NARCIS (Netherlands)

    Ullersma, P.

    1966-01-01

    By means of an exactly solvable model, treated in a previous paper1), the relation between the microscopic and macroscopic susceptibility is discussed. Furthermore, the limits of the validity of Nyquist's theorem are given.

  7. Modeling Individual Subtests of the WAIS IV with Multiple Latent Factors

    OpenAIRE

    2013-01-01

    Performance on a cognitive test can be viewed either as measuring a unitary function or as reflecting the operation of multiple factors. Individual subtests in batteries designed to measure human abilities are commonly modeled as a single latent factor. Several latent factors are then used to model groups of subtests. However these latent factors are not independent as they are related through hierarchical or oblique structures. As a result, the simple structure of subtest performance results...

  8. Investigating depression-like and metabolic parameters in a chronic low-grade inflammation model

    DEFF Research Database (Denmark)

    Fischer, C. W.; Elfving, B.; Lund, S.

    2012-01-01

    (registered trademark) 2ML4, infusion rate 2.5l/day), which delivers LPS through a catheter into the abdomen. Depression-like behavior was assessed as increased time spent immobile in the forced swim test (FST). Peripheral markers of a low-grade inflammation was measured using a high sensitivity ELISA kit and central...... disturbances or sickness behavior. Thus, this model might help elucidating some of the mechanisms underlying inflammation-associated depression, in order to assist in developing more effective treatment strategies for this group of patients....

  9. An alternative Cattell-Horn-Carroll (CHC) factor structure of the WAIS-IV: age invariance of an alternative model for ages 70-90.

    Science.gov (United States)

    Niileksela, Christopher R; Reynolds, Matthew R; Kaufman, Alan S

    2013-06-01

    The Wechsler Adult Intelligence Scale--Fourth Edition (WAIS-IV) is by the far the most popular intelligence test for the assessment of adults in clinical and neuropsychological practice. Despite a number of studies examining the factor structure of the WAIS-IV from a Cattell-Horn-Carroll (CHC) perspective (Benson, Hulac, & Kranzler, 2010; Ward, Bergman, & Hebert, 2012), a CHC interpretation of the WAIS-IV for individuals ages 70 and above has been absent from the literature. The exclusion of individuals ages 70 and above in previous research is likely due to the absence of several key supplemental subtests used to create a full CHC model. We provide an alternative five-factor CHC model of the WAIS-IV which includes only the subtests administered to individuals ages 70 and above in the standardization sample. Our results show (a) the alternative CHC model fits the data well; (b) this alternative CHC model met criteria for partial strict measurement invariance across the life span (only Similarities showed noninvariance) using strict criteria; (c) the five factors for ages 70-90 measure the same five CHC broad abilities identified in previous analyses reported for ages 16-69; and (d) the five-factor CHC solution for ages 70-90 is valid for the entire WAIS-IV age range and can be used whenever examiners administer the core battery but opt not to administer supplemental subtests. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  10. Mathematical Modelling of Allelopathy: IV. Assessment of Contributions of Competition and Allelopathy to Interference by Barley.

    Science.gov (United States)

    Liu, De Li; An, Min; Johnson, I R; Lovett, J V

    2005-04-01

    One of the main challenges to the research on allelopathy is technically the separation of allelopathic effect from competition, and quantitatively, the assessment of the contribution of each component to overall interference. A simple mathematical model is proposed to calculate the contribution of allelopathy and competition to interference. As an example of applying the quantitative model to interference by barley (Hordeum vulgare cv. Triumph), the approach used was an addition of allelopathic effect, by an equivalent amount, to the environment of the test plant (white mustard, Sinapis alba), rather than elimination of competition. Experiments were conducted in glasshouse to determine the magnitude of the contributions of allelopathy and competition to interference by barley. The leachates of living barley roots significantly reduced the total dry weight of white mustard. The model involved the calculation of adjusted densities to an equivalent basis for modelling the contribution of allelopathy and competition to total interference. The results showed that allelopathy contributed 40%, 37% and 43% to interference by barley at 6, 12 and 18 white mustard pot(-1). The consistency in magnitude of the calculated contribution of allelopathic effect by barley across various densities of receiver plant suggested that the adjusted equivalent density is effective and that the model is able to assess the contribution of each component of interference regardless of the density of receiver plant.

  11. Cassini UVIS Observations of the Io Plasma Torus. IV. Modeling Temporal and Azimuthal Variability

    CERN Document Server

    Steffl, A J; Bagenal, F

    2007-01-01

    In this fourth paper in a series, we present the results of our efforts to model the remarkable temporal and azimuthal variability of the Io plasma torus during the Cassini encounter with Jupiter. The long-term (months) temporal variation in the average torus composition observed by the Cassini Ultraviolet Imaging Spectrograph (UVIS) can be modeled by supposing a factor of ~4 increase in the amount of material supplied to the extended neutral clouds that are the source of torus plasma, followed by a gradual decay to more "typical" values. On shorter timescales, the observed 10.07-hour torus periodicity and azimuthal variation in plasma composition, including its surprising modulation with System III longitude, is reproduced by our model using the superposition of two azimuthal variations of suprathermal electrons: a primary hot electron variation that slips 12.5 degrees/day relative to the Jovian magnetic field and a secondary variation that remains fixed in System III longitude.

  12. A New Strategy for Accurately Predicting I-V Electrical Characteristics of PV Modules Using a Nonlinear Five-Point Model

    Directory of Open Access Journals (Sweden)

    Sakaros Bogning Dongue

    2013-01-01

    Full Text Available This paper presents the modelling of electrical I-V response of illuminated photovoltaic crystalline modules. As an alternative method to the linear five-parameter model, our strategy uses advantages of a nonlinear analytical five-point model to take into account the effects of nonlinear variations of current with respect to solar irradiance and of voltage with respect to cells temperature. We succeeded in this work to predict with great accuracy the I-V characteristics of monocrystalline shell SP75 and polycrystalline GESOLAR GE-P70 photovoltaic modules. The good comparison of our calculated results to experimental data provided by the modules manufacturers makes it possible to appreciate the contribution of taking into account the nonlinear effect of operating conditions data on I-V characteristics of photovoltaic modules.

  13. Yang-Mills matrix models with ghosts and derivations of the graded shuffle algebra

    CERN Document Server

    Krishnaswami, Govind S

    2007-01-01

    We consider large-N multi-matrix models that are inspired by the action of Yang-Mills theory including gauge-fixing and ghost terms. We show that the factorized Schwinger-Dyson loop equations of such matrix models have a special algebraic property not shared by generic matrix models. When expressed in terms of the generating series of gluon and ghost correlations G(xi), they are quadratic equations S^i G = G xi^i G in concatenation of correlations. We express S^i in terms of the left annihilation operator and show that it is a derivation of the graded-shuffle product of correlation tensors. A corresponding property of Yang-Mills theory was observed by Makeenko and Migdal in the Wilson loop formulation, where S^i was expressed in terms of the path and area derivatives.

  14. Developing a model for problem-solving in a Grade 4 mathematics classroom

    Directory of Open Access Journals (Sweden)

    Susan Nieuwoudt

    2015-11-01

    Full Text Available The teaching of problem-solving through the development of a problem-solving model was investigated in a Grade 4 mathematics classroom. Learners completed a questionnaire regarding their knowledge of mathematical problem-solving, their attitudes towards problem-solving, as well as their experiences in solving problems. Learners’ responses revealed overall negative beliefs towards problem-solving as well as a lack of knowledge about what problem-solving in mathematics entails. The teacher then involved the learners in a structured learning programme where they worked in cooperative groups of six on different kinds of mathematical problems to solve. The groups regularly engaged in discussions about the different strategies they were using to solve a specific problem and eventually succeeded in formulating a generic problem-solving model they could call their own. The model was effectively used by the learners to solve various mathematical problems, reflecting their levels of cognitive development to a certain extent.

  15. Education as Experimentation: A Planned Variation Model. Volume IV-A: An Evaluation of Follow Through.

    Science.gov (United States)

    Stebbins, Linda B.; And Others

    This segment of the national evaluation study of the Follow Through Planned Variation Model presents background information and discusses the evaluation of the progress of Cohort III entering-kindergarten children during 4 years of Follow Through participation. Also discussed, for the purpose of examining replicability of effects, is the progress…

  16. Black liquor combustion validated recovery boiler modeling: Final year report. Volume 4 (Appendix IV)

    Energy Technology Data Exchange (ETDEWEB)

    Grace, T.M.; Frederick, W.J.; Salcudean, M.; Wessel, R.A.

    1998-08-01

    This project was initiated in October 1990, with the objective of developing and validating a new computer model of a recovery boiler furnace using a computational fluid dynamics (CFD) code specifically tailored to the requirements for solving recovery boiler flows, and using improved submodels for black liquor combustion based on continued laboratory fundamental studies. The key tasks to be accomplished were as follows: (1) Complete the development of enhanced furnace models that have the capability to accurately predict carryover, emissions behavior, dust concentrations, gas temperatures, and wall heat fluxes. (2) Validate the enhanced furnace models, so that users can have confidence in the predicted results. (3) Obtain fundamental information on aerosol formation, deposition, and hardening so as to develop the knowledge base needed to relate furnace model outputs to plugging and fouling in the convective sections of the boiler. (4) Facilitate the transfer of codes, black liquid submodels, and fundamental knowledge to the US kraft pulp industry. Volume 4 contains the following appendix sections: Radiative heat transfer properties for black liquor combustion -- Facilities and techniques and Spectral absorbance and emittance data; and Radiate heat transfer determination of the optical constants of ash samples from kraft recovery boilers -- Calculation procedure; Computation program; Density determination; Particle diameter determination; Optical constant data; and Uncertainty analysis.

  17. Chemistry in Disks. IV. Benchmarking gas-grain chemical models with surface reactions

    CERN Document Server

    Semenov, D; Wakelam, V; Dutrey, A; Chapillon, E; Guilloteau, St; Henning, Th; Launhardt, R; Pietu, V; Schreyer, K

    2010-01-01

    Abridged: We detail and benchmark two sophisticated chemical models developed by the Heidelberg and Bordeaux astrochemistry groups. The main goal of this study is to elaborate on a few well-described tests for state-of-the-art astrochemical codes covering a range of physical conditions and chemical processes, in particular those aimed at constraining current and future interferometric observations of protoplanetary disks. We consider three physical models: a cold molecular cloud core, a hot core, and an outer region of a T Tauri disk. Our chemical network (for both models) is based on the original gas-phase osu_03_2008 ratefile and includes gas-grain interactions and a set of surface reactions for the H-, O-, C-, S-, and N-bearing molecules. The benchmarking is performed with the increasing complexity of the considered processes: (1) the pure gas-phase chemistry, (2) the gas-phase chemistry with accretion and desorption, and (3) the full gas-grain model with surface reactions. Using atomic initial abundances ...

  18. Confidence limits of evolutionary synthesis models. IV An exact statistical formulation

    CERN Document Server

    Cerviño, M; Cervino-Luridiana, N

    2005-01-01

    In this paper we develop a new formalism for the theoretical study of stellar populations. This formalism is as accurate as large Monte Carlo simulations and as simple as standard synthesis models, being at the same time more powerful than either of them. Applying the formalism, we succeed in reproducing and explaining the features of Monte Carlo simulations without the need of performing them. We also derive the scale relations between the luminosity distributions of stellar populations of any size. We show that the distribution of stars in bins is a multinomial distribution, which takes into account the covariance effects introduced by the binning. On the other hand, the formalism do not need of any explicit assumption on the distribution of the number of stars in bins. We also show that there is a bias in the variance customarily computed by synthesis models. We provide mathematical tools to obtain exact confidence intervals of synthesis models. We suggest ways to estimate the shape of a distribution, as i...

  19. A numerical test method of California bearing ratio on graded crushed rocks using particle flow modeling

    Directory of Open Access Journals (Sweden)

    Yingjun Jiang

    2015-04-01

    Full Text Available In order to better understand the mechanical properties of graded crushed rocks (GCRs and to optimize the relevant design, a numerical test method based on the particle flow modeling technique PFC2D is developed for the California bearing ratio (CBR test on GCRs. The effects of different testing conditions and micro-mechanical parameters used in the model on the CBR numerical results have been systematically studied. The reliability of the numerical technique is verified. The numerical results suggest that the influences of the loading rate and Poisson's ratio on the CBR numerical test results are not significant. As such, a loading rate of 1.0–3.0 mm/min, a piston diameter of 5 cm, a specimen height of 15 cm and a specimen diameter of 15 cm are adopted for the CBR numerical test. The numerical results reveal that the CBR values increase with the friction coefficient at the contact and shear modulus of the rocks, while the influence of Poisson's ratio on the CBR values is insignificant. The close agreement between the CBR numerical results and experimental results suggests that the numerical simulation of the CBR values is promising to help assess the mechanical properties of GCRs and to optimize the grading design. Besides, the numerical study can provide useful insights on the mesoscopic mechanism.

  20. Models for Quarks and Elementary Particles. Part IV: How Much do We Know of This Universe?

    Directory of Open Access Journals (Sweden)

    Neumann U. K. W.

    2008-07-01

    Full Text Available Essential laws and principles of the natural sciences were discovered at the high aggre- gation levels of matter such as molecules, metal crystals, atoms and elementary parti- cles. These principles reappear in these models in modified form at the fundamental level of the quarks. However, the following is probably true: since the principles apply at the fundamental level of the quarks they also have a continuing effect at the higher aggregation levels. In the manner of the law of mass action, eight processes for weak interaction are formulated, which are also called Weak Processes here. Rules for quark exchange of the reacting elementary particles are named and the quasi-Euclidian or complex spaces introduced in Part I associated with the respective particles. The weak processes are the gateway to the “second” strand of this universe which we practically do not know. The particles with complex space, e.g. the neutrino, form this second strand. According to the physical model of gravitation from Part III the particles of both strands have >-fields and are thus subject to the superposition, which results in the attraction by gravity of the particles of both strands. The weak processes (7 and (8 offer a fair chance for the elimination of highly radioactive waste.

  1. Light adjoint quarks in the instanton-dyon liquid model. IV.

    Science.gov (United States)

    Liu, Yizhuang; Shuryak, Edward; Zahed, Ismail

    2016-11-01

    We discuss the instanton-dyon liquid model with Nf Majorana quark flavors in the adjoint representation of color S Uc(2 ) at finite temperature. We briefly recall the index theorem on S1×R3 for twisted adjoint fermions in a Bogomolny-Prasad-Sommerfeld (BPS) dyon background of arbitrary holonomy and use the Atiyah-Drinfeld-Hitchin-Manin (ADHM) construction to derive the adjoint antiperiodic zero modes. We use these results to derive the partition function of an interacting instanton-dyon ensemble with Nf light and antiperiodic adjoint quarks. We develop the model in details by mapping the theory on a three-dimensional quantum effective theory with adjoint quarks with manifest S U (Nf)×Z4 Nf symmetry. Using a mean-field analysis at weak coupling and strong screening, we show that center symmetry requires the spontaneous breaking of chiral symmetry, which is shown to only take place for Nf=1 . For a sufficiently dense liquid, we find that the ground state is center symmetric and breaks spontaneously flavor symmetry through S U (Nf)×Z4 Nf→O (Nf). As the liquid dilutes with increasing temperature, center symmetry and chiral symmetry are restored. We present numerical and analytical estimates for the transition temperatures.

  2. Light Adjoint Quarks in the Instanton-Dyon Liquid Model IV

    CERN Document Server

    Liu, Yizhuang; Zahed, Ismail

    2016-01-01

    We discuss the instanton-dyon liquid model with $N_f$ Majorana quark flavors in the adjoint representation of color $SU_c(2)$ at finite temperature. We briefly recall the index theorem on $S^1\\times R^3$ for twisted adjoint fermions in a BPS dyon background of arbitrary holonomy, and use the ADHM construction to explicit the adjoint anti-periodic zero modes. We use these results to derive the partition function of an interacting instanton-dyon ensemble with $N_f$ light and anti-periodic adjoint quarks. We develop the model in details by mapping the theory on a 3-dimensional quantum effective theory with adjoint quarks with manifest $SU(N_f)\\times Z_{4N_f}$ symmetry. Using a mean-field analysis at weak coupling and strong screening, we show that center symmetry requires the spontaneous breaking of chiral symmetry, which is shown to only take place for $N_f=1$. For a sufficiently dense liquid, we find that the ground state is center symmetric and breaks spontaneously flavor symmetry through $SU(N_f)\\times Z_{4N...

  3. Models for Quarks and Elementary Particles --- Part IV: How Much Do We Know of This Universe?

    Directory of Open Access Journals (Sweden)

    Ulrich K. W. Neumann

    2008-07-01

    Full Text Available Essential laws and principles of the natural sciences were discovered at the high aggregation levels of matter such as molecules, metal crystals, atoms and elementary particles. These principles reappear in these models in modified form at the fundamental level of the quarks. However, the following is probably true: since the principles apply at the fundamental level of the quarks they also have a continuing effect at the higher aggregation levels. In the manner of the law of mass action, eight processes for weak interaction are formulated, which are also called Weak Processes here. Rules for quark exchange of the reacting elementary particles are named and the quasi-Euclidian or complex spaces introduced in Part I associated with the respective particles. The weak processes are the gateway to the second strand of this universe which we practically do not know. The particles with complex space, e.g. the neutrino, form this second strand. According to the physical model of gravitation from Part III the particles of both strands have fields and are thus subject to the superposition, which results in the attraction by gravity of the particles of both strands. The weak processes (7 and (8 offer a fair chance for the elimination of highly radioactive waste.

  4. Canonical functions, differential graded symplectic pairs in supergeometry, and Alexandrov-Kontsevich-Schwartz-Zaboronsky sigma models with boundaries

    Science.gov (United States)

    Ikeda, Noriaki; Xu, Xiaomeng

    2014-11-01

    Consistent boundary conditions for Alexandrov-Kontsevich-Schwartz-Zaboronsky (AKSZ) sigma models and the corresponding boundary theories are analyzed. As their mathematical structures, we introduce a generalization of differential graded symplectic manifolds, called twisted QP manifolds, in terms of graded symplectic geometry, canonical functions, and QP pairs. We generalize the AKSZ construction of topological sigma models to sigma models with Wess-Zumino terms and show that all the twisted Poisson-like structures known in the literature can actually be naturally realized as boundary conditions for AKSZ sigma models.

  5. A meta-analytic review of the relationships between the five-factor model and DSM-IV-TR personality disorders: a facet level analysis.

    Science.gov (United States)

    Samuel, Douglas B; Widiger, Thomas A

    2008-12-01

    Theory and research have suggested that the personality disorders contained within the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR) can be understood as maladaptive variants of the personality traits included within the five-factor model (FFM). The current meta-analysis of FFM personality disorder research both replicated and extended the 2004 work of Saulsman and Page (The five-factor model and personality disorder empirical literature: A meta-analytic review. Clinical Psychology Review, 23, 1055-1085) through a facet level analysis that provides a more specific and nuanced description of each DSM-IV-TR personality disorder. The empirical FFM profiles generated for each personality disorder were generally congruent at the facet level with hypothesized FFM translations of the DSM-IV-TR personality disorders. However, notable exceptions to the hypotheses did occur and even some findings that were consistent with FFM theory could be said to be instrument specific.

  6. Physics Based Model for Cryogenic Chilldown and Loading. Part IV: Code Structure

    Science.gov (United States)

    Luchinsky, D. G.; Smelyanskiy, V. N.; Brown, B.

    2014-01-01

    This is the fourth report in a series of technical reports that describe separated two-phase flow model application to the cryogenic loading operation. In this report we present the structure of the code. The code consists of five major modules: (1) geometry module; (2) solver; (3) material properties; (4) correlations; and finally (5) stability control module. The two key modules - solver and correlations - are further divided into a number of submodules. Most of the physics and knowledge databases related to the properties of cryogenic two-phase flow are included into the cryogenic correlations module. The functional form of those correlations is not well established and is a subject of extensive research. Multiple parametric forms for various correlations are currently available. Some of them are included into correlations module as will be described in details in a separate technical report. Here we describe the overall structure of the code and focus on the details of the solver and stability control modules.

  7. The conceptual basis of mathematics in cardiology IV: statistics and model fitting.

    Science.gov (United States)

    Bates, Jason H T; Sobel, Burton E

    2003-06-01

    This is the fourth in a series of four articles developed for the readers of Coronary Artery Disease. Without language ideas cannot be articulated. What may not be so immediately obvious is that they cannot be formulated either. One of the essential languages of cardiology is mathematics. Unfortunately, medical education does not emphasize, and in fact, often neglects empowering physicians to think mathematically. Reference to statistics, conditional probability, multicompartmental modeling, algebra, calculus and transforms is common but often without provision of genuine conceptual understanding. At the University of Vermont College of Medicine, Professor Bates developed a course designed to address these deficiencies. The course covered mathematical principles pertinent to clinical cardiovascular and pulmonary medicine and research. It focused on fundamental concepts to facilitate formulation and grasp of ideas. This series of four articles was developed to make the material available for a wider audience. The articles will be published sequentially in Coronary Artery Disease. Beginning with fundamental axioms and basic algebraic manipulations they address algebra, function and graph theory, real and complex numbers, calculus and differential equations, mathematical modeling, linear system theory and integral transforms and statistical theory. The principles and concepts they address provide the foundation needed for in-depth study of any of these topics. Perhaps of even more importance, they should empower cardiologists and cardiovascular researchers to utilize the language of mathematics in assessing the phenomena of immediate pertinence to diagnosis, pathophysiology and therapeutics. The presentations are interposed with queries (by Coronary Artery Disease abbreviated as CAD) simulating the nature of interactions that occurred during the course itself. Each article concludes with one or more examples illustrating application of the concepts covered to

  8. Contribution of alpha3(IV)alpha4(IV)alpha5(IV) Collagen IV to the Mechanical Properties of the Glomerular Basement Membrane

    Science.gov (United States)

    Gyoneva, Lazarina

    The glomerular basement membrane (GBM) is a vital part of the blood-urine filtration barrier in the kidneys. In healthy GBMs, the main tension-resisting component is alpha3(IV)alpha4(IV)alpha5(IV) type IV collagen, but in some diseases it is replaced by other collagen IV isoforms. As a result, the GBM becomes leaky and disorganized, ultimately resulting in kidney failure. Our goal is to understanding the biomechanical aspects of the alpha3(IV)alpha4(IV)alpha5(IV) chains and how their absence could be responsible for (1) the initial injury to the GBM and (2) progression to kidney failure. A combination of experiments and computational models were designed for that purpose. A model basement membrane was used to compare experimentally the distensibility of tissues with the alpha3(IV)alpha4(IV)alpha5(IV) chains present and missing. The experiments showed basement membranes containing alpha3(IV)alpha4(IV)alpha5(IV) chains were less distensible. It has been postulated that the higher level of lateral cross-linking (supercoiling) in the alpha3(IV)alpha4(IV)alpha5(IV) networks contributes additional strength/stability to basement membranes. In a computational model of supercoiled networks, we found that supercoiling greatly increased the stiffness of collagen IV networks but only minimally decreased the permeability, which is well suited for the needs of the GBM. It is also known that the alpha3(IV)alpha4(IV)alpha5(IV) networks are more protected from enzymatic degradation, and we explored their significance in GBM remodeling. Our simulations showed that the more protected network was needed to prevent the system from entering a dangerous feedback cycle due to autoregulation mechanisms in the kidneys. Overall, the work adds to the evidence of biomechanical differences between the alpha3(IV)alpha4(IV)alpha5(IV) networks and other collagen IV networks, points to supercoiling as the main source of biomechanical differences, discusses the suitability of alpha3(IV)alpha4(IV

  9. 煤的热解研究IV. 官能团热解模型%Fundamental Study of Coal Pyrolysis IV. Functional Group Pyrolysis Model

    Institute of Scientific and Technical Information of China (English)

    朱学栋; 朱子彬; 张成芳; 唐黎华

    2001-01-01

    将煤的热解视为煤中官能团的断裂反应,从而建立FG官能团热解模型。模型认为:热解生成物焦油和甲烷由煤中脂肪-CH裂解生成,而CO2、CO和H2O由煤中相对应官能团裂解生成,反应的活化能呈Gaussian分布。模型很好地解释了热解生成物与煤中官能团的相应关系,完整地描述了煤的热解生成物生成的全过程。%Considering the coal pyrolysis as its functional groups thermal decomposition, we founded the functional-group pyrolysis model. The model pointed out that the aliphatic-CH decomposition is the competition process between tar and CH4 forming reaction, and CO2, CO and H2O evolve from carboxyl, ether and hydroxyl groups. All reactions are described by a large number of first order parallel reactions having a Gaussian distribution of activation energies. This model gave a good explanation of the relation between thermal decomposition products and functional groups of coal, and the whole process of coal pyrolysis was described thoroughly by this model.

  10. Unlocking the Standard Model. IV. N=2 generations of quarks : spectrum and mixing

    CERN Document Server

    Machet, Bruno

    2013-01-01

    The Glashow-Salam-Weinberg model for 2 generations of quarks is extended to 8 composite Higgs multiplets, with no adjunction of extra fermions. It is the minimal number of Higgs doublets required to suitably account, simultaneously, for the spectrum of pseudoscalar mesons that can be built with 4 quarks and for the mass of the W gauge bosons. These masses being used as input, together with elementary low energy considerations for the pions, we calculate all other parameters, masses and couplings. We focus in this work on the spectrum of the 8 Higgs bosons (which all potentially contribute to the W and quark masses), and on the mixing (Cabibbo) angle, leaving the study of couplings to a subsequent work. The Higgs bosons fall into one triplet, two doublets and one singlet. In the triplet stand three states with masses \\sqrt{2} x that of heaviest pseudoscalar meson D_s, which, for 2 generations, pushes them up to 2.80 GeV. The 2 components of the first doublet have masses close to 1.25 GeV. The singlet has a mas...

  11. The BOSS Emission-Line Lens Survey. IV. : Smooth Lens Models for the BELLS GALLERY Sample

    CERN Document Server

    Shu, Yiping; Mao, Shude; Kochanek, Christopher S; Pérez-Fournon, Ismael; Oguri, Masamune; Montero-Dorta, Antonio D; Cornachione, Matthew A; Marques-Chaves, Rui; Zheng, Zheng; Brownstein, Joel R; Ménard, Brice

    2016-01-01

    We present \\textsl{Hubble Space Telescope} (\\textsl{HST}) F606W-band imaging observations of 21 galaxy-Ly$\\alpha$ emitter lens candidates in the Baryon Oscillation Spectroscopic Survey (BOSS) Emission-Line Lens Survey (BELLS) for GALaxy-Ly$\\alpha$ EmitteR sYstems (BELLS GALLERY) survey. 17 systems are confirmed to be definite lenses with unambiguous evidence of multiple imaging. The lenses are primarily massive early-type galaxies (ETGs) at redshifts of approximately $0.55$, while the lensed sources are Ly$\\alpha$ emitters (LAEs) at redshifts from 2 to 3. Although the \\textsl{HST} imaging data are well fit by smooth lens models consisting of singular isothermal ellipsoids in an external shear field, a thorough exploration of dark substructures in the lens galaxies is required. The Einstein radii of the BELLS GALLERY lenses are on average $60\\%$ larger than those of the BELLS lenses because of the much higher source redshifts which will allow a detailed investigation of the radius evolution of the mass profile...

  12. Sixth Grade Students' Content-Specific Competencies and Challenges in Learning the Seasons Through Modeling

    Science.gov (United States)

    Sung, Ji Young; Oh, Phil Seok

    2017-06-01

    Recent science education reform initiatives suggest that learning in science should be organized on the basis of scientists' actual practices including the development and use of models. In line with this, the current study adapted three types of modeling practices to teach two Korean 6th grade science classes the causes of the Earth's seasons. Specifically, the study aimed to identify the students' content-specific competencies and challenges based on fine-grained descriptions and analyses of two target groups' cases. Data included digital recordings of modeling-based science lessons in the two classes, the teacher's and students' artifacts, and interviews with the students. These multiple types of data were analyzed complementarily and qualitatively. It was revealed that the students had a competency in constructing models to generate the desired phenomenon (i.e., seasons). They had difficulty, however, in considering the tilt of the Earth's rotation axis as a cause of the seasons and in finding a proper way of representing the Sun's meridian altitude on a globe. But, when the students were helped and guided by the teacher and peers' interventions, they were able to revise their models in alignment with the scientific understanding of the seasons. Based on these findings, the teacher's pedagogical roles, which include using student competencies as resources, asking physical questions, and explicit guidance on experimentation skills, were recommended to support successful incorporations of modeling practices in the science classroom.

  13. The use of sensory perception indicators for improving the characterization and modelling of total petroleum hydrocarbon (TPH) grade in soils.

    Science.gov (United States)

    Roxo, Sónia; de Almeida, José António; Matias, Filipa Vieira; Mata-Lima, Herlander; Barbosa, Sofia

    2016-03-01

    This paper proposes a multistep approach for creating a 3D stochastic model of total petroleum hydrocarbon (TPH) grade in potentially polluted soils of a deactivated oil storage site by using chemical analysis results as primary or hard data and classes of sensory perception variables as secondary or soft data. First, the statistical relationship between the sensory perception variables (e.g. colour, odour and oil-water reaction) and TPH grade is analysed, after which the sensory perception variable exhibiting the highest correlation is selected (oil-water reaction in this case study). The probabilities of cells belonging to classes of oil-water reaction are then estimated for the entire soil volume using indicator kriging. Next, local histograms of TPH grade for each grid cell are computed, combining the probabilities of belonging to a specific sensory perception indicator class and conditional to the simulated values of TPH grade. Finally, simulated images of TPH grade are generated by using the P-field simulation algorithm, utilising the local histograms of TPH grade for each grid cell. The set of simulated TPH values allows several calculations to be performed, such as average values, local uncertainties and the probability of the TPH grade of the soil exceeding a specific threshold value.

  14. Managing Model Data Introduced Uncertainties in Simulator Predictions for Generation IV Systems via Optimum Experimental Design

    Energy Technology Data Exchange (ETDEWEB)

    Turinsky, Paul J [North Carolina State Univ., Raleigh, NC (United States); Abdel-Khalik, Hany S [North Carolina State Univ., Raleigh, NC (United States); Stover, Tracy E [North Carolina State Univ., Raleigh, NC (United States)

    2011-03-01

    An optimization technique has been developed to select optimized experimental design specifications to produce data specifically designed to be assimilated to optimize a given reactor concept. Data from the optimized experiment is assimilated to generate posteriori uncertainties on the reactor concept’s core attributes from which the design responses are computed. The reactor concept is then optimized with the new data to realize cost savings by reducing margin. The optimization problem iterates until an optimal experiment is found to maximize the savings. A new generation of innovative nuclear reactor designs, in particular fast neutron spectrum recycle reactors, are being considered for the application of closing the nuclear fuel cycle in the future. Safe and economical design of these reactors will require uncertainty reduction in basic nuclear data which are input to the reactor design. These data uncertainty propagate to design responses which in turn require the reactor designer to incorporate additional safety margin into the design, which often increases the cost of the reactor. Therefore basic nuclear data needs to be improved and this is accomplished through experimentation. Considering the high cost of nuclear experiments, it is desired to have an optimized experiment which will provide the data needed for uncertainty reduction such that a reactor design concept can meet its target accuracies or to allow savings to be realized by reducing the margin required due to uncertainty propagated from basic nuclear data. However, this optimization is coupled to the reactor design itself because with improved data the reactor concept can be re-optimized itself. It is thus desired to find the experiment that gives the best optimized reactor design. Methods are first established to model both the reactor concept and the experiment and to efficiently propagate the basic nuclear data uncertainty through these models to outputs. The representativity of the experiment

  15. Managing Model Data Introduced Uncertainties in Simulator Predictions for Generation IV Systems via Optimum Experimental Design

    Energy Technology Data Exchange (ETDEWEB)

    Turinsky, Paul J; Abdel-Khalik, Hany S; Stover, Tracy E

    2011-03-31

    An optimization technique has been developed to select optimized experimental design specifications to produce data specifically designed to be assimilated to optimize a given reactor concept. Data from the optimized experiment is assimilated to generate posteriori uncertainties on the reactor concept’s core attributes from which the design responses are computed. The reactor concept is then optimized with the new data to realize cost savings by reducing margin. The optimization problem iterates until an optimal experiment is found to maximize the savings. A new generation of innovative nuclear reactor designs, in particular fast neutron spectrum recycle reactors, are being considered for the application of closing the nuclear fuel cycle in the future. Safe and economical design of these reactors will require uncertainty reduction in basic nuclear data which are input to the reactor design. These data uncertainty propagate to design responses which in turn require the reactor designer to incorporate additional safety margin into the design, which often increases the cost of the reactor. Therefore basic nuclear data needs to be improved and this is accomplished through experimentation. Considering the high cost of nuclear experiments, it is desired to have an optimized experiment which will provide the data needed for uncertainty reduction such that a reactor design concept can meet its target accuracies or to allow savings to be realized by reducing the margin required due to uncertainty propagated from basic nuclear data. However, this optimization is coupled to the reactor design itself because with improved data the reactor concept can be re-optimized itself. It is thus desired to find the experiment that gives the best optimized reactor design. Methods are first established to model both the reactor concept and the experiment and to efficiently propagate the basic nuclear data uncertainty through these models to outputs. The representativity of the experiment

  16. Modelling of graded index waveguide fabricated by ion exchange on Er3+ doped glass

    Institute of Scientific and Technical Information of China (English)

    Shao Gong-Wang; Jin Guo-Liang

    2009-01-01

    A general numerical tool, based on thermal diffusion equation and full-vectorial eigen-mode equation, has been presented for the systematic analysis of graded index channel waveguide fabricated by ion exchange on Er3+ doped glass. Finite difference method with full-vectorial formulation (FV-FDM) is applied to solving the full-vectorial modes of graded index channel waveguide for the first time. The coupled difference equations based on magnetic fields in FV-FDM are derived from the Taylor series expansion and accurate formulation of boundary conditions. Hybrid nature of vectorial guided modes for both pump (980 nm) and signal light (1550 nm) are demonstrated by the simulation. Results show that the fabrication parameters of ion exchange, such as channel opening width and time ratio of second step to first step in ion exchange, have large influence on the properties of waveguide. By optimizing the fabrication parameters, maintenance of monomode for signal light and improvement of the gain dynamics can be achieved in Er3+ doped waveguide amplifier (EDWA) fabricated by ion exchange technique. This theoretical model is significant for the design and fabrication of EDWA with ion exchange technique. Furthermore, a single polarization EDWA, which operates at wavelength from 1528 nm to 1541 nm for HE polarization, is numerically designed.

  17. "Generalized" algebraic Bethe ansatz, Gaudin-type models and Zp-graded classical r-matrices

    Science.gov (United States)

    Skrypnyk, T.

    2016-12-01

    We consider quantum integrable systems associated with reductive Lie algebra gl (n) and Cartan-invariant non-skew-symmetric classical r-matrices. We show that under certain restrictions on the form of classical r-matrices "nested" or "hierarchical" Bethe ansatz usually based on a chain of subalgebras gl (n) ⊃ gl (n - 1) ⊃ . . . ⊃ gl (1) is generalized onto the other chains or "hierarchies" of subalgebras. We show that among the r-matrices satisfying such the restrictions there are "twisted" or Zp-graded non-skew-symmetric classical r-matrices. We consider in detail example of the generalized Gaudin models with and without external magnetic field associated with Zp-graded non-skew-symmetric classical r-matrices and find the spectrum of the corresponding Gaudin-type hamiltonians using nested Bethe ansatz scheme and a chain of subalgebras gl (n) ⊃ gl (n -n1) ⊃ gl (n -n1 -n2) ⊃ gl (n - (n1 + . . . +np-1)), where n1 +n2 + . . . +np = n.

  18. FY17 Status Report on the Initial Development of a Constitutive Model for Grade 91 Steel

    Energy Technology Data Exchange (ETDEWEB)

    Messner, M. C. [Argonne National Lab. (ANL), Argonne, IL (United States); Phan, V. -T. [Argonne National Lab. (ANL), Argonne, IL (United States); Sham, T. -L. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2017-07-01

    Grade 91 is a candidate structural material for high temperature advanced reactor applications. Existing ASME Section III, Subsection HB, Subpart B simplified design rules based on elastic analysis are setup as conservative screening tools with the intent to supplement these screening rules with full inelastic analysis when required. The Code provides general guidelines for suitable inelastic models but does not provide constitutive model implementations. This report describes the development of an inelastic constitutive model for Gr. 91 steel aimed at fulfilling the ASME Code requirements and being included into a new Section III Code appendix, HBB-Z. A large database of over 300 experiments on Gr. 91 was collected and converted to a standard XML form. Five families of Gr. 91 material models were identified in the literature. Of these five, two are potentially suitable for use in the ASME code. These two models were implemented and evaluated against the experimental database. Both models have deficiencies so the report develops a framework for developing and calibrating an improved model. This required creating a new modeling method for representing changes in material rate sensitivity across the full ASME allowable temperature range for Gr. 91 structural components: room temperature to 650° C. On top of this framework for rate sensitivity the report describes calibrating a model for work hardening and softening in the material using genetic algorithm optimization. Future work will focus on improving this trial model by including tension/compression asymmetry observed in experiments and necessary to capture material ratcheting under zero mean stress and by improving the optimization and analysis framework.

  19. Determination of Uncertainties for +III and +IV Actinide Solubilities in the WIPP Geochemistry Model for the 2009 Compliance Recertification Application

    Science.gov (United States)

    Ismail, A. E.; Xiong, Y.; Nowak, E. J.; Brush, L. H.

    2009-12-01

    The Waste Isolation Pilot Plant (WIPP) is a U.S. Department of Energy (DOE) repository in southeast New Mexico for defense-related transuranic (TRU) waste. Every five years, the DOE is required to submit an application to the Environmental Protection Agency (EPA) demonstrating the WIPP’s continuing compliance with the applicable EPA regulations governing the repository. Part of this recertification effort involves a performance assessment—a probabilistic evaluation of the repository performance with respect to regulatory limits on the amount of releases from the repository to the accessible environment. One of the models used as part of the performance assessment process is a geochemistry model, which predicts solubilities of the radionuclides in the brines that may enter the repository in the different scenarios considered by the performance assessment. The dissolved actinide source term comprises actinide solubilities, which are input parameters for modeling the transport of radionuclides as a result of brine flow through and from the repository. During a performance assessment, the solubilities are modeled as the product of a “base” solubility determined from calculations based on the chemical conditions expected in the repository, and an uncertainty factor that describes the potential deviations of the model from expected behavior. We will focus here on a discussion of the uncertainties. To compute a cumulative distribution function (CDF) for the uncertainties, we compare published, experimentally measured solubility data to predictions made using the established WIPP geochemistry model. The differences between the solubilities observed for a given experiment and the calculated solubilities from the model are used to form the overall CDF, which is then sampled as part of the performance assessment. We will discuss the methodology used to update the CDF’s for the +III actinides, obtained from data for Nd, Am, and Cm, and the +IV actinides, obtained

  20. A Teaching Model for Scaffolding 4th Grade Students' Scientific Explanation Writing

    Science.gov (United States)

    Yang, Hsiu-Ting; Wang, Kuo-Hua

    2014-08-01

    Improving students scientific explanations is one major goal of science education. Both writing activities and concept mapping are reported as effective strategies for enhancing student learning of science. The purpose of this study was to examine the effect of a teaching model, named the DCI model, which integrates a Descriptive explanation writing activity, Concept mapping, and an Interpretive explanation writing activity, is introduced in a 4th grade science class to see if it would improve students' scientific explanations and understanding. A quasi-experimental design, including a non-randomized comparison group and a pre- and post-test design, was adopted for this study. An experimental group of 25 students were taught using the DCI teaching model, while a comparison group received a traditional lecture teaching. A rubric and content analysis was used to assess students' scientific explanations. The independent sample t test was used to measure difference in conceptual understanding between the two groups, before and after instruction. Then, the paired t test analysis was used to understand the promotion of the DCI teaching model. The results showed that students in the experimental group performed better than students in the comparison group, both in scientific concept understanding and explanation. Suggestions for using concept mapping and writing activities (the DCI teaching model) in science classes are provided in this study.

  1. ARX-NNPLS Model Based Optimization Strategy and Its Application in Polymer Grade Transition Process

    Institute of Scientific and Technical Information of China (English)

    费正顺; 胡斌; 叶鲁彬; 梁军

    2012-01-01

    Since it is often difficult to build differential algebraic equations (DAEs) for chemical processes, a new data-based modeling approach is proposed using ARX (AutoRegressive with eXogenous inputs) combined with neural network under partial least squares framework (ARX-NNPLS), in which less specific knowledge of the process is required but the input and output data. To represent the dynamic and nonlinear behavior of the process, the ARX combined with neural network is used in the partial least squares (PLS) inner model between input and output latent variables. In the proposed dynamic optimization strategy based on the ARX-NNPLS model, neither parameterization nor iterative solving process for DAEs is needed as the ARX-NNPLS model gives a proper representation for the dynamic behavior of the process, and the computing time is greatly reduced compared to conventional control vector parameterization method. To demonstrate the ARX-NNPLS model based optimization strategy, the polyethylene grade transition in gas phase fluidized-bed reactor is taken into account. The optimization results show that the final optimal trajectory of quality index determined by the new approach moves faster to the target values and the computing time is much less.

  2. The acquired preparedness risk model applied to smoking in 5th grade children.

    Science.gov (United States)

    Combs, Jessica L; Spillane, Nichea S; Caudill, Leann; Stark, Brittany; Smith, Gregory T

    2012-03-01

    The very early onset of smoking predicts numerous health problems. The authors conducted the first test of one risk model for elementary school age smoking, known as the acquired preparedness (AP) model of risk, in a cross-sectional sample of 309 5th grade children. The model posits that (a) impulsivity-related personality traits contribute to risk for a variety of risky, maladaptive behaviors; (b) smoking expectancies confer risk only for smoking; and (c) the personality traits contribute to the formation of high risk expectancies for reinforcement from smoking, which in turn increases the likelihood of early onset smoking. The model was supported: the high-risk personality traits distinguished children engaging in any risky, maladaptive behavior from other children, and the smoking expectancies differentiated smokers from all other children. The relationship between personality tendencies to act rashly when experiencing intense positive or negative emotions and smoker status was partially mediated by expectancies for reinforcement from smoking. This model should be investigated longitudinally.

  3. NMR studies demonstrate a unique AAB composition and chain register for a heterotrimeric type IV collagen model peptide containing a natural interruption site.

    Science.gov (United States)

    Xiao, Jianxi; Sun, Xiuxia; Madhan, Balaraman; Brodsky, Barbara; Baum, Jean

    2015-10-02

    All non-fibrillar collagens contain interruptions in the (Gly-X-Y)n repeating sequence, such as the more than 20 interruptions found in chains of basement membrane type IV collagen. Two selectively doubly labeled peptides are designed to model a site in type IV collagen with a GVG interruption in the α1(IV) and a corresponding GISLK sequence within the α2(IV) chain. CD and NMR studies on a 2:1 mixture of these two peptides support the formation of a single-component heterotrimer that maintains the one-residue staggering in the triple-helix, has a unique chain register, and contains hydrogen bonds at the interruption site. Formation of hydrogen bonds at interruption sites may provide a driving force for self-assembly and chain register in type IV and other non-fibrillar collagens. This study illustrates the potential role of interruptions in the structure, dynamics, and folding of natural collagen heterotrimers and forms a basis for understanding their biological role.

  4. Using Autocorrelation Analysis to Build the Evaluating Model of Train Impulse Grade

    Institute of Scientific and Technical Information of China (English)

    LIU Chuanbo; MO Yimin

    2006-01-01

    To the shortage of the traditional analysis methods about train impact, this paper put forward a new method using autocorrelation theory and virtual instrument technology to analyze train impulse. Using a double-MCU system, the acceleration signals were acquired at different speed by train, and were transmitted into PC through USB interface. Besides the impulse signals, the acquisition data included other useless signals. The autocorrelation function was small when trains run steadily, but was greater during train impact happened. So the autocorrelation function was adopted to distill the valid impulse data. After frequency domain analyzed and autocorrelation analyzed on the Virtual Instrument flat, a new train impulse grade assessment criterion was built, based on the correlation peak and the width of the peak. In experiment, the impulse signal was separated from noise signal well and truly, and the quantitative model of evaluating train impulse was believable. This system possessed a certain extent theory value and application value.

  5. Investigating depression-like and metabolic parameters in a chronic low-grade inflammation model

    DEFF Research Database (Denmark)

    Fischer, C. W.; Elfving, B.; Lund, S.

    2012-01-01

    that elevated markers of inflammation predict a poor response to treatment. Furthermore, increasing evidences show that metabolic abnormalities such as obesity and diabetes mellitus type 2 are associated with a low-grade inflammation. Objectives: The aim of this study is to investigate the effects of a systemic...... levels of pro-inflammatory cytokines (TNF-alpha, IL-1, IL-6) together with the expression of enzymes involved in the tryptophan-kynurenine pathway, will be analyzed in specific brain regions using real-time qPCR. Body weight and food intake was measured once a week, while fasting glucose and insulin...... disturbances or sickness behavior. Thus, this model might help elucidating some of the mechanisms underlying inflammation-associated depression, in order to assist in developing more effective treatment strategies for this group of patients....

  6. A Comparison of Estimation Methods for a Multi-unidimensional Graded Response IRT Model.

    Science.gov (United States)

    Kuo, Tzu-Chun; Sheng, Yanyan

    2016-01-01

    This study compared several parameter estimation methods for multi-unidimensional graded response models using their corresponding statistical software programs and packages. Specifically, we compared two marginal maximum likelihood (MML) approaches (Bock-Aitkin expectation-maximum algorithm, adaptive quadrature approach), four fully Bayesian algorithms (Gibbs sampling, Metropolis-Hastings, Hastings-within-Gibbs, blocked Metropolis), and the Metropolis-Hastings Robbins-Monro (MHRM) algorithm via the use of IRTPRO, BMIRT, and MATLAB. Simulation results suggested that, when the intertrait correlation was low, these estimation methods provided similar results. However, if the dimensions were moderately or highly correlated, Hastings-within-Gibbs had an overall better parameter recovery of item discrimination and intertrait correlation parameters. The performances of these estimation methods with different sample sizes and test lengths are also discussed.

  7. Recovery of Graded Response Model Parameters: A Comparison of Marginal Maximum Likelihood and Markov Chain Monte Carlo Estimation

    Science.gov (United States)

    Kieftenbeld, Vincent; Natesan, Prathiba

    2012-01-01

    Markov chain Monte Carlo (MCMC) methods enable a fully Bayesian approach to parameter estimation of item response models. In this simulation study, the authors compared the recovery of graded response model parameters using marginal maximum likelihood (MML) and Gibbs sampling (MCMC) under various latent trait distributions, test lengths, and…

  8. Testing Expert-Based versus Student-Based Cognitive Models for a Grade 3 Diagnostic Mathematics Assessment

    Science.gov (United States)

    Roduta Roberts, Mary; Alves, Cecilia B.; Chu, Man-Wai; Thompson, Margaret; Bahry, Louise M.; Gotzmann, Andrea

    2014-01-01

    The purpose of this study was to evaluate the adequacy of three cognitive models, one developed by content experts and two generated from student verbal reports for explaining examinee performance on a grade 3 diagnostic mathematics test. For this study, the items were developed to directly measure the attributes in the cognitive model. The…

  9. Applying a Multiple Group Causal Indicator Modeling Framework to the Reading Comprehension Skills of Third, Seventh, and Tenth Grade Students

    Science.gov (United States)

    Tighe, Elizabeth L.; Wagner, Richard K.; Schatschneider, Christopher

    2015-01-01

    This study demonstrates the utility of applying a causal indicator modeling framework to investigate important predictors of reading comprehension in third, seventh, and tenth grade students. The results indicated that a 4-factor multiple indicator multiple indicator cause (MIMIC) model of reading comprehension provided adequate fit at each grade…

  10. Applying a Multiple Group Causal Indicator Modeling Framework to the Reading Comprehension Skills of Third, Seventh, and Tenth Grade Students

    Science.gov (United States)

    Tighe, Elizabeth L.; Wagner, Richard K.; Schatschneider, Christopher

    2015-01-01

    This study demonstrates the utility of applying a causal indicator modeling framework to investigate important predictors of reading comprehension in third, seventh, and tenth grade students. The results indicated that a 4-factor multiple indicator multiple indicator cause (MIMIC) model of reading comprehension provided adequate fit at each grade…

  11. Assessment of Grade-Level Differences in Coping Behavior among Adolescents Using Multidimensional Scaling Single-Ideal-Point Model

    Science.gov (United States)

    Ding, Cody; Yang, Dong

    2013-01-01

    The purpose of the study was to examine grade-level differences in coping behaviors among adolescents using a probabilistic multidimensional scaling (MDS) single-ideal-point model. Using data from students in middle school and at college, this article illustrated the MDS single-ideal-point model as an alternative to examine students' typical…

  12. Administration of a dipeptidyl peptidase IV inhibitor enhances the intestinal adaptation in a mouse model of short bowel syndrome

    DEFF Research Database (Denmark)

    Okawada, Manabu; Holst, Jens Juul; Teitelbaum, Daniel H

    2011-01-01

    Glucagon-like peptide-2 induces small intestine mucosal epithelial cell proliferation and may have benefit for patients who suffer from short bowel syndrome. However, glucagon-like peptide-2 is inactivated rapidly in vivo by dipeptidyl peptidase IV. Therefore, we hypothesized that selectively...... inhibiting dipeptidyl peptidase IV would prolong the circulating life of glucagon-like peptide-2 and lead to increased intestinal adaptation after development of short bowel syndrome....

  13. Feature extraction and classifcation in surface grading application using multivariate statistical projection models

    Science.gov (United States)

    Prats-Montalbán, José M.; López, Fernando; Valiente, José M.; Ferrer, Alberto

    2007-01-01

    In this paper we present an innovative way to simultaneously perform feature extraction and classification for the quality control issue of surface grading by applying two well known multivariate statistical projection tools (SIMCA and PLS-DA). These tools have been applied to compress the color texture data describing the visual appearance of surfaces (soft color texture descriptors) and to directly perform classification using statistics and predictions computed from the extracted projection models. Experiments have been carried out using an extensive image database of ceramic tiles (VxC TSG). This image database is comprised of 14 different models, 42 surface classes and 960 pieces. A factorial experimental design has been carried out to evaluate all the combinations of several factors affecting the accuracy rate. Factors include tile model, color representation scheme (CIE Lab, CIE Luv and RGB) and compression/classification approach (SIMCA and PLS-DA). In addition, a logistic regression model is fitted from the experiments to compute accuracy estimates and study the factors effect. The results show that PLS-DA performs better than SIMCA, achieving a mean accuracy rate of 98.95%. These results outperform those obtained in a previous work where the soft color texture descriptors in combination with the CIE Lab color space and the k-NN classi.er achieved a 97.36% of accuracy.

  14. Bi-functionally Graded Electrode Supported SOFC Modeling and Computational Thermal Fluid Analysis for Experimental Design

    Energy Technology Data Exchange (ETDEWEB)

    Shi, J.; Xue, X.

    2011-01-01

    A comprehensive 3D CFD model is developed for a bi-electrode supported cell (BSC) SOFC. The model includes complicated transport phenomena of mass/heat transfer, charge (electron and ion) migration, and electrochemical reaction. The uniqueness of the modeling study is that functionally graded porous electrode property is taken into account, including not only linear but nonlinear porosity distributions. Extensive numerical analysis is performed to elucidate the effects of both porous microstructure distributions and operating condition on cell performance. Results indicate that cell performance is strongly dependent on both operating conditions and porous microstructure distributions of electrodes. Using the proposed fuel/gas feeding design, the uniform hydrogen distribution within porous anode is achieved; the oxygen distribution within the cathode is dependent on porous microstructure distributions as well as pressure loss conditions. Simulation results show that fairly uniform temperature distribution can be obtained with the proposed fuel/gas feeding design. The modeling results can be employed to guide experimental design of BSC test and provide pre-experimental analysis, as a result, to circumvent high cost associated with try-and-error experimental design and setup.

  15. UNSTEADY FLOWS OF A GENERALIZED SECOND GRADE FLUID WITH THE FRACTIONAL DERIVATIVE MODEL BETWEEN TWO PARALLEL PLATES

    Institute of Scientific and Technical Information of China (English)

    TAN Wenchang; XU Mingyu

    2004-01-01

    The fractional calculus approach in the constitutive relationship model of a generalized second grade fluid is introduced. Exact analytical solutions are obtained for a class of unsteady flows for the generalized second grade fluid with the fractional derivative model between two parallel plates by using the Laplace transform and Fourier transform for fractional calculus. The unsteady flows are generated by the impulsive motion or periodic oscillation of one of the plates. In addition, the solutions of the shear stresses at the plates are also determined.

  16. THE IMPACT OF ARCS MOTIVATION MODEL ON MOTIVATION AND SUCCESS LEVEL OF PRIMARY 4TH GRADE STUDENTS IN SOCIAL STUDIES

    OpenAIRE

    Mustafa TAHİROĞLU

    2015-01-01

    The purpose of this study is to detect the impact of a teaching-learning process, structured taking the components of ARCS Motivation Model into consideration, on the motivation and success level of primary grade 4 students in social studies. In scope of the study, grouped pretest-posttest testing model is used. The experimental group consists of 32, and the control group 30 students. In order to collect research data, the “Grade 4 and 5 Social Studies Motivation Scale” and “Social Studies Ac...

  17. The nature and role of physical models in enhancing sixth grade students' mental models of groundwater and groundwater processes

    Science.gov (United States)

    Duffy, Debra Lynne Foster

    Through a non-experimental descriptive and comparative mixed-methods approach, this study investigated the experiences of sixth grade earth science students with groundwater physical models through an extended SE learning cycle format. The data collection was based on a series of quantitative and qualitative research tools intended to investigate students' ideas and changes in ideas rather than measure their achievement. The measures included a groundwater survey, classroom observations, and one-on-one follow-up student interviews for triangulation of data sources. The research was carried out at a K-12 independent school in eastern Virginia using two classes of sixth grade earth science students (n=30). The findings suggest that physical models help students identify the components porosity and permeability with respect to water flow in groundwater systems. Higher levels of system thinking were best demonstrated in model components that allowed students to experience groundwater pollution activities and pumping groundwater wells. However, the results also indicated that due to model constraints, students can develop misconceptions during the use of physical models, specifically more complex physical models as in the Groundwater Exploration Activity Model. A pure discovery learning format while using physical models without guidance or formative assessment probes can lead to misconceptions about groundwater processes as well as confusion between model attributes and real world groundwater systems. The implications of this study relate directly to the inclusion of groundwater in the new national science standards released in 2011; A Framework for K-12 Science Standard; Practices, Crosscutting Concepts, and Core Ideas (NRC, 2011). The new national standards, as in other educational reform efforts, will have the ability to affect curricular and instructional strategies in science education. From the results of this study, it was concluded that best practices for using

  18. Gleason grading of prostate histology utilizing manifold regularization via statistical shape model of manifolds

    Science.gov (United States)

    Sparks, Rachel; Madabhushi, Anant

    2012-03-01

    Gleason patterns of prostate cancer histopathology, characterized primarily by morphological and architectural attributes of histological structures (glands and nuclei), have been found to be highly correlated with disease aggressiveness and patient outcome. Gleason patterns 4 and 5 are highly correlated with more aggressive disease and poorer patient outcome, while Gleason patterns 1-3 tend to reflect more favorable patient outcome. Because Gleason grading is done manually by a pathologist visually examining glass (or digital) slides, subtle morphologic and architectural differences of histological attributes may result in grading errors and hence cause high inter-observer variability. Recently some researchers have proposed computerized decision support systems to automatically grade Gleason patterns by using features pertaining to nuclear architecture, gland morphology, as well as tissue texture. Automated characterization of gland morphology has been shown to distinguish between intermediate Gleason patterns 3 and 4 with high accuracy. Manifold learning (ML) schemes attempt to generate a low dimensional manifold representation of a higher dimensional feature space while simultaneously preserving nonlinear relationships between object instances. Classification can then be performed in the low dimensional space with high accuracy. However ML is sensitive to the samples contained in the dataset; changes in the dataset may alter the manifold structure. In this paper we present a manifold regularization technique to constrain the low dimensional manifold to a specific range of possible manifold shapes, the range being determined via a statistical shape model of manifolds (SSMM). In this work we demonstrate applications of the SSMM in (1) identifying samples on the manifold which contain noise, defined as those samples which deviate from the SSMM, and (2) accurate out-of-sample extrapolation (OSE) of newly acquired samples onto a manifold constrained by the SSMM. We

  19. Computer simulation and modeling of graded bandgap CuInSe{sub 2}/CdS based solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Dhingra, A.; Rothwarf, A. [Drexel Univ., Philadelphia, PA (United States). Dept. of Electrical and Computer Engineering

    1996-04-01

    This paper proposes the use of graded bandgap absorber material, to improve the low open-circuit voltage (V{sub oc}) seen in CuInSe{sub 2}/CdS solar cells, without sacrificing the short-circuit current density (J{sub sc}). It also proposes a p-i-n model for the CuInSe{sub 2}/CdS solar cell, where the intrinsic region is the graded bandgap CIS. Reflecting surfaces are provided at the p-i and n-i interfaces to trap the light in the narrow intrinsic region for maximum generation of electron and hole pairs (EHP`s). This optical confinement results in a 25--40% increase in the number of photons absorbed. An extensive numerical simulator was developed, which provides a 1-D self-consistent solution for Poisson`s equation and the two continuity equations for electrons and holes. This simulator was used to generate J-V curves to delineate the effect of different grading profiles on cell performance. The effects of a uniform bandgap, normal grading, reverse grading, and a low bandgap notch have been considered. Having established the inherent advantages to these grading profiles an optimal doubly graded structure is proposed. Replacing the thick CdS (2.42ev) layer assumed in the simulations with a wide gap semiconductor such as ZnO (3.35ev) increases all current densities by about 5 mA/cm{sup 2}, and increases the optimal calculated efficiency from 17.9% to roughly 21% for a doubly graded structure with a thickness of 1 {micro}m and bandgaps ranging from 1.3 eV to 1.5 eV.

  20. Stochastic kinetic model of two component system signalling reveals all-or-none, graded and mixed mode stochastic switching responses.

    Science.gov (United States)

    Kierzek, Andrzej M; Zhou, Lu; Wanner, Barry L

    2010-03-01

    Two-component systems (TCSs) are prevalent signal transduction systems in bacteria that control innumerable adaptive responses to environmental cues and host-pathogen interactions. We constructed a detailed stochastic kinetic model of two component signalling based on published data. Our model has been validated with flow cytometry data and used to examine reporter gene expression in response to extracellular signal strength. The model shows that, depending on the actual kinetic parameters, TCSs exhibit all-or-none, graded or mixed mode responses. In accordance with other studies, positively autoregulated TCSs exhibit all-or-none responses. Unexpectedly, our model revealed that TCSs lacking a positive feedback loop exhibit not only graded but also mixed mode responses, in which variation of the signal strength alters the level of gene expression in induced cells while the regulated gene continues to be expressed at the basal level in a substantial fraction of cells. The graded response of the TCS changes to mixed mode response by an increase of the translation initiation rate of the histidine kinase. Thus, a TCS is an evolvable design pattern capable of implementing deterministic regulation and stochastic switches associated with both graded and threshold responses. This has implications for understanding the emergence of population diversity in pathogenic bacteria and the design of genetic circuits in synthetic biology applications. The model is available in systems biology markup language (SBML) and systems biology graphical notation (SBGN) formats and can be used as a component of large-scale biochemical reaction network models.

  1. Micromechanics Modeling of Functionally Graded Interphase Regions in Carbon Nanotube-Polymer Composites

    Science.gov (United States)

    Seidel, Gary D.; Lagoudas, Dimitris C.; Frankland, Sarah Jane V.; Gates, Thomas S.

    2006-01-01

    The effective elastic properties of a unidirectional carbon fiber/epoxy lamina in which the carbon fibers are coated with single-walled carbon nanotubes are modeled herein through the use of a multi-scale method involving the molecular dynamics/equivalent continuum and micromechanics methods. The specific lamina representative volume element studied consists of a carbon fiber surrounded by a region of epoxy containing a radially varying concentration of carbon nanotubes which is then embedded in the pure epoxy matrix. The variable concentration of carbon nanotubes surrounding the carbon fiber results in a functionally graded interphase region as the properties of the interphase region vary according to the carbon nanotube volume fraction. Molecular dynamics and equivalent continuum methods are used to assess the local effective properties of the carbon nanotube/epoxy comprising the interphase region. Micromechanics in the form of the Mori-Tanaka method are then applied to obtain the global effective properties of the graded interphase region wherein the carbon nanotubes are randomly oriented. Finally, the multi-layer composite cylinders micromechanics approach is used to obtain the effective lamina properties from the lamina representative volume element. It was found that even very small quantities of carbon nanotubes (0.36% of lamina by volume) coating the surface of the carbon fibers in the lamina can have a significant effect (8% increase) on the transverse properties of the lamina (E22, k23, G23 and G12) with almost no affect on the lamina properties in the fiber direction (E11 and v12).

  2. Case studies of fifth-grade student modeling in science through programming: Comparison of modeling practices and conversations

    Science.gov (United States)

    Louca, Loucas

    This is a descriptive case study investigating the use of two computer-based programming environments (CPEs), MicroWorlds(TM) (MW) and Stagecast Creator(TM) (SC), as modeling tools for collaborative fifth grade science learning. In this study I investigated how CPEs might support fifth grade student work and inquiry in science. There is a longstanding awareness of the need to help students learn about models and modeling in science, and CPEs are promising tools for this. A computer program can be a model of a physical system, and modeling through programming may make the process more tangible: Programming involves making decisions and assumptions; the code is used to express ideas; running the program shows the implications of those ideas. In this study I have analyzed and compared students' activities and conversations in two after-school clubs, one working with MW and the other with SC. The findings confirm the promise of CPEs as tools for teaching practices of modeling and science, and they suggest advantages and disadvantages to that purpose of particular aspects of CPE designs. MW is an open-ended, textual CPE that uses procedural programming. MW students focused on breaking down phenomena into small programmable pieces, which is useful for scientific modeling. Developing their programs, the students focused on writing, testing and debugging code, which are also useful for scientific modeling. SC is a non-linear, object-oriented CPE that uses visual program language. SC students saw their work as creating games. They were focused on the overall story which they then translated it into SC rules, which was in conflict with SC's object-oriented interface. However, telling the story of individual causal agents was useful for scientific modeling. Programming in SC was easier, whereas reading code in MW was more tangible. The latter helped MW students to use the code as the representation of the phenomenon rather than merely as a tool for creating a simulation. The

  3. Implications of Bed-Schematization in Morphological Models with Graded Sediment

    Science.gov (United States)

    Sloff, K.; Mosselman, E.

    2007-12-01

    For modeling morphology in river with graded-sediment beds, generally methods are used that subdivide the sediment into separate size fractions, and that subdivide the bed into discrete layers. In the past years we have applied and analyzed numerical models using these methods for various river cases, including the full range of time-dependent conditions and spatial variations. It has been found from these applications that particularly the schematization of the bed into discrete layers and the interactions with the transport rate have a serious influence on the outcomes and predictability of these models. The thickness of the active-layer or mixing layer on the bed surface directly determines the time scale of bed- composition changes. Choosing a very thin active layer will lead to very fast adjustments of bed composition to changes or gradients in conditions, such that (generally slow) morphological responses will be cancelled. A more physically sound choice of the layer thickness (e.g., on basis of bed form dimensions), leading to a thicker layer, causes a deceleration of bed-composition changes and propagation. Applications to the Rhine River have shown that this causes the time-scales of morphological changes and bed composition changes to approach each other leading to a stronger interaction between grain size and morphological changes. Tracer experiments in the gravel bed of the German Rhine indicate that a relative thick active layer is required to simulate the slowly migration (2 to 5 km/year) of the granite tracers downstream. Note that both prototype data and model results are showing a dispersion of bed composition disturbances, as propagation speed for different fractions is different. In the model approach sediment-transport rates are coupled to availability of sediment fractions in the active layer. Transport models and hiding and exposure models strongly react to the composition and evolution of the layer, and analysis of the equations reveals some

  4. The effects of Georgia's Choice curricular reform model on third grade science scores on the Georgia Criterion Referenced Competency Test

    Science.gov (United States)

    Phemister, Art W.

    The purpose of this study was to evaluate the effectiveness of the Georgia's Choice reading curriculum on third grade science scores on the Georgia Criterion Referenced Competency Test from 2002 to 2008. In assessing the effectiveness of the Georgia's Choice curriculum model this causal comparative study examined the 105 elementary schools that implemented Georgia's Choice and 105 randomly selected elementary schools that did not elect to use Georgia's Choice. The Georgia's Choice reading program used intensified instruction in an effort to increase reading levels for all students. The study used a non-equivalent control group with a pretest and posttest design to determine the effectiveness of the Georgia's Choice curriculum model. Findings indicated that third grade students in Non-Georgia's Choice schools outscored third grade students in Georgia's Choice schools across the span of the study.

  5. Characteristics of type IV collagen unfolding under various pH conditions as a model of pathological disorder in tissue.

    Science.gov (United States)

    Shimizu, Akio; Kawai, Kenichi; Yanagino, Miki; Wakiyama, Toshiko; Machida, Minoru; Kameyama, Kohji; Naito, Zenya

    2007-07-01

    The overall structure of type IV collagen is the same at neutral and acidic pH, as determined by circular dichroism spectra. The heating rate dependence of denaturation midpoint temperature (T(m)) shows that type IV collagen is unstable at body temperature, similarly to type I collagen. The heating rate dependence of T(m) at neutral pH has two phases, but that at acidic pH apparently has a single phase. The T(m) of the first phase (lower T(m)) at neutral pH is consistent with that at acidic pH, and the activation energy of these phases is consistent, within experimental error. The triple helix region of type IV collagen corresponding to the second phase (higher T(m)) at neutral pH is thermally stable when compared to the triple helical structure at acidic pH. At acidic pH, as the loosely packed and unstable region has spread throughout the whole molecule, the thermal transition is thought to be cooperative and is observed as a single phase. Structural flexibility is related to protein function and assembly; therefore, the unstable structure and increased flexibility of type IV collagen induced at acidic pH may affect diseases accompanied by type IV collagen disorder.

  6. Separation of type and grade in cervical tumours using non-mono-exponential models of diffusion-weighted MRI

    Energy Technology Data Exchange (ETDEWEB)

    Winfield, Jessica M.; Collins, David J.; Morgan, Veronica A.; DeSouza, Nandita M. [The Royal Marsden NHS Foundation Trust, MRI Unit, Sutton, Surrey (United Kingdom); The Institute of Cancer Research, Cancer Research UK Cancer Imaging Centre, Division of Radiotherapy and Imaging, London (United Kingdom); Orton, Matthew R. [The Institute of Cancer Research, Cancer Research UK Cancer Imaging Centre, Division of Radiotherapy and Imaging, London (United Kingdom); Ind, Thomas E.J. [The Royal Marsden NHS Foundation Trust, Gynaecology Unit, London (United Kingdom); Attygalle, Ayoma; Hazell, Steve [The Royal Marsden NHS Foundation Trust, Department of Histopathology, London (United Kingdom)

    2017-02-15

    Assessment of empirical diffusion-weighted MRI (DW-MRI) models in cervical tumours to investigate whether fitted parameters distinguish between types and grades of tumours. Forty-two patients (24 squamous cell carcinomas, 14 well/moderately differentiated, 10 poorly differentiated; 15 adenocarcinomas, 13 well/moderately differentiated, two poorly differentiated; three rare types) were imaged at 3 T using nine b-values (0 to 800 s mm{sup -2}). Mono-exponential, stretched exponential, kurtosis, statistical, and bi-exponential models were fitted. Model preference was assessed using Bayesian Information Criterion analysis. Differences in fitted parameters between tumour types/grades and correlation between fitted parameters were assessed using two-way analysis of variance and Pearson's linear correlation coefficient, respectively. Non-mono-exponential models were preferred by 83 % of tumours with bi-exponential and stretched exponential models preferred by the largest numbers of tumours. Apparent diffusion coefficient (ADC) and diffusion coefficients from non-mono-exponential models were significantly lower in poorly differentiated tumours than well/moderately differentiated tumours. α (stretched exponential), K (kurtosis), f and D* (bi-exponential) were significantly different between tumour types. Strong correlation was observed between ADC and diffusion coefficients from other models. Non-mono-exponential models were preferred to the mono-exponential model in DW-MRI data from cervical tumours. Parameters of non-mono-exponential models showed significant differences between types and grades of tumours. (orig.)

  7. Assessment of a model for achieving competency in administration and scoring of the WAIS-IV in postgraduate psychology students

    Directory of Open Access Journals (Sweden)

    Rachel Margaret Roberts

    2015-05-01

    Full Text Available There is a need for an evidence-based approach to training professional psychologists in the administration and scoring of standardized tests such as the Wechsler Adult Intelligence Scale (WAIS due to substantial evidence that these tasks are associated with numerous errors that have the potential to significantly impact clients’ lives. Twenty three postgraduate psychology students underwent training in using the WAIS-IV according to a best-practice teaching model that involved didactic teaching, independent study of the test manual, and in-class practice with teacher supervision and feedback. Video recordings and test protocols from a role-played test administration were analyzed for errors according to a comprehensive checklist with self, peer, and faculty member reviews. 91.3% of students were rated as having demonstrated competency in administration and scoring. All students were found to make errors, with substantially more errors being detected by the faculty member than by self or peers. Across all subtests, the most frequent errors related to failure to deliver standardized instructions verbatim from the manual. The failure of peer and self-reviews to detect the majority of the errors suggests that novice feedback (self or peers may be ineffective to eliminate errors and the use of more senior peers may be preferable. It is suggested that involving senior trainees, recent graduates and/or experienced practitioners in the training of postgraduate students may have benefits for both parties, promoting a peer-learning and continuous professional development approach to the development and maintenance of skills in psychological assessment.

  8. IV-SNS的休闲经济模式及社会影响%IV-SNS Leisure Economy Model and Its Social Influence in China

    Institute of Scientific and Technical Information of China (English)

    张海鸥

    2014-01-01

    The paper puts forward the concept IV -SNS,namely the Social Network Site based on Interactive Video for relaxation. China's IV-SNS formed industrial scale in 2005 and the registered users and virtual consumption have explosive growth until 2012 . IV-SNS in the form of leisure industry became the focus of China's network economy. By studying the leisure economy model of IV - SNS,the paper explains the experience process,relaxation way,and revenue sources of IV-SNS. The social influence of IV-SNS is analyzed and the supervision issues wor-thy of attention are proposed. The competition and cooperation of China's IV-SNS industry will lead to merger and reorganization. A super IV-SNS will appear in China which will deeply influ-ence the social public opinion and ideology of the public.%首先提出IV-SNS的概念,即基于视讯互动的网络休闲社区。中国IV-SNS在2005年初具产业规模,至2012年,其注册用户及虚拟消费呈爆发式增长,以休闲产业的形式成为中国网络经济的焦点。通过对IV-SNS的休闲经济模式进行研究,阐释了IV-SNS的体验流程、休闲方式、营收来源,对其巨大的社会影响进行分析,并提出值得注意的监管问题。中国IV-SNS产业内的竞合必然导致兼并重组,会出现一个网络休闲娱乐的超级平台,将深刻影响公众的社会舆论与意识形态。

  9. Sample Size Requirements for Estimation of Item Parameters in the Multidimensional Graded Response Model

    Directory of Open Access Journals (Sweden)

    Shengyu eJiang

    2016-02-01

    Full Text Available Likert types of rating scales in which a respondent chooses a response from an ordered set of response options are used to measure a wide variety of psychological, educational, and medical outcome variables. The most appropriate item response theory model for analyzing and scoring these instruments when they provide scores on multiple scales is the multidimensional graded response model (MGRM. A simulation study was conducted to investigate the variables that might affect item parameter recovery for the MGRM. Data were generated based on different sample sizes, test lengths, and scale intercorrelations. Parameter estimates were obtained through the flexiMIRT software. The quality of parameter recovery was assessed by the correlation between true and estimated parameters as well as bias and root- mean-square-error. Results indicated that for the vast majority of cases studied a sample size of N = 500 provided accurate parameter estimates, except for tests with 240 items when 1,000 examinees were necessary to obtain accurate parameter estimates. Increasing sample size beyond N = 1,000 did not increase the accuracy of MGRM parameter estimates.

  10. Item Response Theory Analyses of the Parent and Teacher Ratings of the DSM-IV ADHD Rating Scale

    Science.gov (United States)

    Gomez, Rapson

    2008-01-01

    The graded response model (GRM), which is based on item response theory (IRT), was used to evaluate the psychometric properties of the inattention and hyperactivity/impulsivity symptoms in an ADHD rating scale. To accomplish this, parents and teachers completed the DSM-IV ADHD Rating Scale (DARS; Gomez et al., "Journal of Child Psychology and…

  11. Radiation thermo-chemical models of protoplanetary discs. IV. Modelling CO ro-vibrational emission from Herbig Ae discs

    NARCIS (Netherlands)

    Thi, W. F.; Kamp, I.; Woitke, P.; van der Plas, G.; Bertelsen, R.; Wiesenfeld, L.

    2013-01-01

    Context. The carbon monoxide (CO) ro-vibrational emission from discs around Herbig Ae stars and T Tauri stars with strong ultraviolet emissions suggests that fluorescence pumping from the ground X1Σ+ to the electronic A1Π state of CO should be taken into account in disc models. Aims: We wish to unde

  12. Radiation thermo-chemical models of protoplanetary discs IV. Modelling CO ro-vibrational emission from Herbig Ae discs

    NARCIS (Netherlands)

    Thi, W. F.; Kamp, I.; Woitke, P.; van der Plas, G.; Bertelsen, R.; Wiesenfeld, L.

    2013-01-01

    Context. The carbon monoxide (CO) ro-vibrational emission from discs around Herbig Ae stars and T Tauri stars with strong ultraviolet emissions suggests that fluorescence pumping from the ground X-1 Sigma(+) to the electronic A(1)Pi state of CO should be taken into account in disc models. Aims. We w

  13. High bone sialoprotein (BSP expression correlates with increased tumor grade and predicts a poorer prognosis of high-grade glioma patients.

    Directory of Open Access Journals (Sweden)

    Tao Xu

    Full Text Available OBJECTIVES: To investigate the expression and prognostic value of bone sialoprotein (BSP in glioma patients. METHODS: We determined the expression of BSP using real-time RT-PCR and immunohistochemistry in tissue microarrays containing 15 normal brain and 270 glioma samples. Cumulative survival was calculated by the Kaplan-Meier method and analyzed by the log-rank test. Univariate and multivariate analyses were performed by the stepwise forward Cox regression model. RESULTS: Both BSP mRNA and protein levels were significantly elevated in high-grade glioma tissues compared with those of normal brain and low-grade glioma tissues, and BSP expression positively correlated with tumor grade (P<0.001. Univariate and multivariate analysis showed high BSP expression was an independent prognostic factor for a shorter progression-free survival (PFS and overall survival (OS in both grade III and grade IV glioma patients [hazard ratio (HR = 2.549 and 3.154 for grade III glioma, and HR = 1.637 and 1.574 for grade IV glioma, respectively]. Patients with low BSP expression had a significantly longer median OS and PFS than those with high BSP expression. Small extent of resection and lineage of astrocyte served as independent risk factors of both shorter PFS and OS in grade III glioma patients; GBM patients without O(6-methylguanine (O(6-meG DNA methyltransferase (MGMT methylation and Karnofsky performance score (KPS less than 70 points were related to poor prognosis. Lack of radiotherapy related to shorter OS but not affect PFS in both grade III and grade IV glioma patients. CONCLUSION: High BSP expression occurs in a significant subset of high-grade glioma patients and predicts a poorer outcome. The study identifies a potentially useful molecular marker for the categorization and targeted therapy of gliomas.

  14. Using Logistic Regression to Model New York City Restaurant Grades Over a Two-Year Period

    Directory of Open Access Journals (Sweden)

    David Nadler

    2014-07-01

    Full Text Available A knowledge gap exists in the role of restaurant type on the prediction of attaining the highest grade possible from the local health inspection agency. This study identified disparities using logistic regression between the issuance of a Grade A and restaurant type and location. This study tested the eight most inspected types of restaurants within the City of New York and calculated the odds ratios of their receiving the highest inspection grade by the New York City Department of Health and Mental Hygiene. A fitted equation has been proposed for the prediction of receiving the highest inspection grade based upon the citywide results of these eight restaurant types from calendar years 2011 and 2012. The results suggest that certain styles of restaurants have lower odds of receiving the highest grade in comparison to American-style restaurants.

  15. Nanoelectronic Modeling (NEMO): Moving from commercial grade 1-D simulation to prototype 3-D simulation

    Science.gov (United States)

    Klimeck, Gerhard

    2001-03-01

    The quantum mechanical functionality of commercially pursued heterostructure devices such as resonant tunneling diodes (RTDs), quantum well infrared photodetectors, and quantum well lasers are enabled by material variations on an atomic scale. The creation of these heterostructure devices is realized in a vast design space of material compositions, layer thicknesses and doping profiles. The full experimental exploration of this design space is unfeasible and a reliable design tool is needed. The Nanoelectronic Modeling tool (NEMO) is one of the first commercial grade attempts for such a modeling tool. NEMO was developed as a general-purpose quantum mechanics-based 1-D device design and analysis tool from 1993-97 by the Central Research Laboratory of Texas Instruments (later Raytheon Systems). NEMO enables(R. Lake, G. Klimeck, R. C. Bowen, and D. Jovanovic, J. Appl. Phys. 81), 7845 (1997). the fundamentally sound inclusion of the required(G. Klimeck et al.), in the 1997 55th Annual Device Research Conference Digest, (IEEE, NJ, 1997), p. 92^,(R. C. Bowen et al.), J. Appl. Phys 81, 3207 (1997). physics: bandstructure, scattering, and charge self-consistency based on the non-equilibrium Green function approach. A new class of devices which require full 3-D quantum mechanics based models is starting to emerge: quantum dots, or in general semiconductor based deca-nano devices. We are currently building a 3-D modeling tool based on NEMO to include the important physics to understand electronic stated in such superscaled structures. This presentation will overview various facets of the NEMO 1-D tool such electron transport physics in RTDs, numerical technology, software engineering and graphical user interface. The lessons learned from that work are now entering the NEMO 3-D development and first results using the NEMO 3-D prototype will be shown. More information about the publically available NEMO 1-D executables can be found at http://hpc.jpl.nasa.gov/ PEP/gekco/nemo

  16. A physiologically-inspired model of numerical classification based on graded stimulus coding

    Directory of Open Access Journals (Sweden)

    John Pearson

    2010-01-01

    Full Text Available In most natural decision contexts, the process of selecting among competing actions takes place in the presence of informative, but potentially ambiguous, stimuli. Decisions about magnitudes—quantities like time, length, and brightness that are linearly ordered—constitute an important subclass of such decisions. It has long been known that perceptual judgments about such quantities obey Weber’s Law, wherein the just-noticeable difference in a magnitude is proportional to the magnitude itself. Current physiologically inspired models of numerical classification assume discriminations are made via a labeled line code of neurons selectively tuned for numerosity, a pattern observed in the firing rates of neurons in the ventral intraparietal area (VIP of the macaque. By contrast, neurons in the contiguous lateral intraparietal area (LIP signal numerosity in a graded fashion, suggesting the possibility that numerical classification could be achieved in the absence of neurons tuned for number. Here, we consider the performance of a decision model based on this analog coding scheme in a paradigmatic discrimination task—numerosity bisection. We demonstrate that a basic two-neuron classifier model, derived from experimentally measured monotonic responses of LIP neurons, is sufficient to reproduce the numerosity bisection behavior of monkeys, and that the threshold of the classifier can be set by reward maximization via a simple learning rule. In addition, our model predicts deviations from Weber Law scaling of choice behavior at high numerosity. Together, these results suggest both a generic neuronal framework for magnitude-based decisions and a role for reward contingency in the classification of such stimuli.

  17. Current treatment of low grade gliomas

    NARCIS (Netherlands)

    M.J. van den Bent (Martin); T.A.B. Snijders (Tom); J.E.C. Bromberg (Jacolien)

    2012-01-01

    textabstractLow grade gliomas affect predominantly young adults, and have a relatively favorable prognosis compared to grade III and grade IV gliomas. The challenge for an optimal management of these patients is to find the balance between an optimal survival and the preservation of neurological fun

  18. A Longitudinal Study of Reading Comprehension Achievement from Grades 3 to 10: Investigating Models of Stability, Cumulative Growth, and Compensation

    Science.gov (United States)

    Kwiatkowska-White, Bozena; Kirby, John R.; Lee, Elizabeth A.

    2016-01-01

    This longitudinal study of 78 Canadian English-speaking students examined the applicability of the stability, cumulative, and compensatory models in reading comprehension development. Archival government-mandated assessments of reading comprehension at Grades 3, 6, and 10, and the Canadian Test of Basic Skills measure of reading comprehension…

  19. Empirical Validation of Integrated Learning Performances for Hydrologic Phenomena: 3rd-Grade Students' Model-Driven Explanation-Construction

    Science.gov (United States)

    Forbes, Cory T.; Zangori, Laura; Schwarz, Christina V.

    2015-01-01

    Water is a crucial topic that spans the K-12 science curriculum, including the elementary grades. Students should engage in the articulation, negotiation, and revision of model-based explanations about hydrologic phenomena. However, past research has shown that students, particularly early learners, often struggle to understand hydrologic…

  20. The Effect of 3D-Modeling Training on Students' Spatial Reasoning Relative to Gender and Grade

    Science.gov (United States)

    Šafhalter, Andrej; Vukman, Karin Bakracevic; Glodež, Srecko

    2016-01-01

    The aim of this research was to establish whether gender and age have an impact on spatial reasoning and its development through the use of 3D modeling. The study was conducted on a sample of 196 children from sixth to ninth grade, of whom 95 represented the experimental group and 101 the control group. The experimental group received 3D modeling…

  1. A Longitudinal Study of Reading Comprehension Achievement from Grades 3 to 10: Investigating Models of Stability, Cumulative Growth, and Compensation

    Science.gov (United States)

    Kwiatkowska-White, Bozena; Kirby, John R.; Lee, Elizabeth A.

    2016-01-01

    This longitudinal study of 78 Canadian English-speaking students examined the applicability of the stability, cumulative, and compensatory models in reading comprehension development. Archival government-mandated assessments of reading comprehension at Grades 3, 6, and 10, and the Canadian Test of Basic Skills measure of reading comprehension…

  2. An analysis of surface acoustic wave propagation in a plate of functionally graded materials with a layered model

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In a homogeneous plate, Rayleigh waves will have a symmetric and anti-symmetric mode regarding to the mid-plane with different phase velocities. If plate properties vary along the thickness, or the plate is of functionally graded material (FGM), the symmetry of modes and frequency behavior will be modified, thus producing dif-ferent features for engineering applications such as amplifying or reducing the velocity and deformation. This kind of effect can also be easily realized by utilizing a layered structure with desired material properties that can produce these effects in terms of velocity and displacements, since Rayleigh waves in a solid with gen-eral material property grading schemes are difficult to analyze with known methods. Solutions from layered structures with exponential and polynomial property grad-ing schemes are obtained from the layered model and comparisons with known analytical results are made to validate the method and examine possible applica-tions of such structures in engineering.

  3. Development of a model and computer code to describe solar grade silicon production processes

    Science.gov (United States)

    Gould, R. K.; Srivastava, R.

    1979-01-01

    Two computer codes were developed for describing flow reactors in which high purity, solar grade silicon is produced via reduction of gaseous silicon halides. The first is the CHEMPART code, an axisymmetric, marching code which treats two phase flows with models describing detailed gas-phase chemical kinetics, particle formation, and particle growth. It can be used to described flow reactors in which reactants, mix, react, and form a particulate phase. Detailed radial gas-phase composition, temperature, velocity, and particle size distribution profiles are computed. Also, deposition of heat, momentum, and mass (either particulate or vapor) on reactor walls is described. The second code is a modified version of the GENMIX boundary layer code which is used to compute rates of heat, momentum, and mass transfer to the reactor walls. This code lacks the detailed chemical kinetics and particle handling features of the CHEMPART code but has the virtue of running much more rapidly than CHEMPART, while treating the phenomena occurring in the boundary layer in more detail.

  4. A model marine-science curriculum for fourth-grade pupils in Florida

    Science.gov (United States)

    Schulte, Philip James

    This dissertation focused on the development of a model marine-science curriculum for fourth-grade pupils in the State of Florida. The curriculum was developed using grounded theory research method, including a component of data collected from an on-line survey administered to 106 professional educators and marine biologists. The results of the data collection and analysis showed a definitive necessity for teacher preparedness, multidisciplinary content, and inquiry-based science instruction. Further, three important factors emerged: (a) collaborative grouping increases achievement; (b) field excursions significantly impact student motivation; (c) standardized testing influences curriculum development. The curriculum is organized as an 11-day unit, with detailed lesson plans presented in standard curricular format and with all components correlated to the Florida State Educational Standards. The curriculum incorporates teacher preparation, multimedia presentations, computer-assisted instruction, scientific art appreciation, and replication as well as assessment factors. The curriculum addresses topics of ichthyology, marine animal identification, environmental conservation and protection, marine animal anatomy, water safety, environmental stewardship, and responsible angling techniques. The components of the curriculum were discussed with reference to the literature on which it was based and recommendations for future research were addressed.

  5. Outcomes of different Class II treatments : Comparisons using the American Board of Orthodontics Model Grading System.

    Science.gov (United States)

    Akinci Cansunar, Hatice; Uysal, Tancan

    2016-07-01

    The aim of this study was to evaluate the clinical outcomes of three different Class II treatment modalities followed by fixed orthodontic therapy, using the American Board of Orthodontics Model Grading System (ABO-MGS). As a retrospective study, files of patients treated at postgraduate orthodontic  clinics in different cities in Turkey was randomly selected. From 1684 posttreatment records, 669 patients were divided into three groups: 269 patients treated with extraction of two upper premolars, 198 patients treated with cervical headgear, and 202 patients treated with functional appliances. All the cases were evaluated by one researcher using ABO-MGS. The χ (2), Z test, and multivariate analysis of variance were used for statistical evaluation (p < 0.05). No significant differences were found among the groups in buccolingual inclination, overjet, occlusal relationship, and root angulation. However, there were significant differences in alignment, marginal ridge height, occlusal contact, interproximal contact measurements, and overall MGS average scores. The mean treatment time between the extraction and functional appliance groups was significantly different (p = 0.017). According to total ABO-MGS scores, headgear treatment had better results than functional appliances. The headgear group had better tooth alignment than the extraction group. Headgear treatment resulted in better occlusal contacts than the functional appliances and had lower average scores for interproximal contact measurements. Functional appliances had the worst average scores for marginal ridge height. Finally, the functional appliance group had the longest treatment times.

  6. Exploring the sensitivity on a soil area-slope-grading relationship to changes in process parameters using a pedogenesis model

    Science.gov (United States)

    Welivitiya, W. D. Dimuth P.; Willgoose, Garry R.; Hancock, Greg R.; Cohen, Sagy

    2016-08-01

    This paper generalises the physical dependence of the relationship between contributing area, local slope, and the surface soil grading using a pedogenesis model and allows an exploration of soilscape self-organisation. A parametric study was carried out using different parent materials, erosion, and weathering mechanisms. These simulations confirmed the generality of the area-slope-d50 relationship. The relationship is also true for other statistics of soil grading (e.g. d10,d90) and robust for different depths within the profile. For small area-slope regimes (i.e. hillslopes with small areas and/or slopes) only the smallest particles can be mobilised by erosion and the area-slope-d50 relationship appears to reflect the erosion model and its Shield's Stress threshold. For higher area-slope regimes, total mobilization of the entire soil grading occurs and self-organisation reflects the relative entrainment of different size fractions. Occasionally the interaction between the in-profile weathering and surface erosion draws the bedrock to the surface and forms a bedrock outcrop. The study also shows the influence on different depth-dependent in-profile weathering functions in the formation of the equilibrium soil profile and the grading characteristics of the soil within the profile. We outline the potential of this new model and its ability to numerically explore soil and landscape properties.

  7. Evaluating WAIS-IV structure through a different psychometric lens: structural causal model discovery as an alternative to confirmatory factor analysis.

    Science.gov (United States)

    van Dijk, Marjolein J A M; Claassen, Tom; Suwartono, Christiany; van der Veld, William M; van der Heijden, Paul T; Hendriks, Marc P H

    2017-07-20

    Since the publication of the WAIS-IV in the U.S. in 2008, efforts have been made to explore the structural validity by applying factor analysis to various samples. This study aims to achieve a more fine-grained understanding of the structure of the Dutch language version of the WAIS-IV (WAIS-IV-NL) by applying an alternative analysis based on causal modeling in addition to confirmatory factor analysis (CFA). The Bayesian Constraint-based Causal Discovery (BCCD) algorithm learns underlying network structures directly from data and assesses more complex structures than is possible with factor analysis. WAIS-IV-NL profiles of two clinical samples of 202 patients (i.e. patients with temporal lobe epilepsy and a mixed psychiatric outpatient group) were analyzed and contrasted with a matched control group (N = 202) selected from the Dutch standardization sample of the WAIS-IV-NL to investigate internal structure by means of CFA and BCCD. With CFA, the four-factor structure as proposed by Wechsler demonstrates acceptable fit in all three subsamples. However, BCCD revealed three consistent clusters (verbal comprehension, visual processing, and processing speed) in all three subsamples. The combination of Arithmetic and Digit Span as a coherent working memory factor could not be verified, and Matrix Reasoning appeared to be isolated. With BCCD, some discrepancies from the proposed four-factor structure are exemplified. Furthermore, these results fit CHC theory of intelligence more clearly. Consistent clustering patterns indicate these results are robust. The structural causal discovery approach may be helpful in better interpreting existing tests, the development of new tests, and aid in diagnostic instruments.

  8. Grade 12 French students? use of a thermodynamic model for predicting the direction of incomplete chemical changes

    OpenAIRE

    Kermen, Isabelle; Méheut, Martine

    2010-01-01

    Abstract The authors of the current chemistry curriculum -implemented in grade 12 in France- provided a criterion of change allowing predictions of direction of chemical changes and pointed out the difference to be made between experimental facts and models. A study analysing part of the curriculum content and the effects of teaching this content on students? reasoning was conducted. The content analysis presents the functioning of the thermodynamic model which highlights the links...

  9. West Meets East: The Early Civilizations of India and China. Grade 6 Model Lesson for Unit IV. California History-Social Science Course Models.

    Science.gov (United States)

    Zachlod, Michelle, Ed.

    This unit for sixth graders focuses on the origins of Chinese civilization, the rise of early Chinese imperial centers, and the breakdown of order by the beginning of the sixth century B.C. Among the topics in the unit are: Early history and geography of India; Buddhism; Early history and geography of China; Confucius; and Culture, politics,…

  10. Testing a Nested Skills Model of the Relations among Invented Spelling, Accurate Spelling, and Word Reading, from Kindergarten to Grade 1

    Science.gov (United States)

    Sénéchal, Monique

    2017-01-01

    The goal was to assess the role of invented spelling to subsequent reading and spelling as proposed by the Nested Skills Model of Early Literacy Acquisition. 107 English-speaking children were tested at the beginning of kindergarten and grade 1, and at the end of grade 1. The findings provided support for the proposed model. First, the role played…

  11. Braze alloy process and strength characterization studies for 18 nickel grade 200 maraging steel with application to wind tunnel models

    Science.gov (United States)

    Bradshaw, James F.; Sandefur, Paul G., Jr.; Young, Clarence P., Jr.

    1991-01-01

    A comprehensive study of braze alloy selection process and strength characterization with application to wind tunnel models is presented. The applications for this study include the installation of stainless steel pressure tubing in model airfoil sections make of 18 Ni 200 grade maraging steel and the joining of wing structural components by brazing. Acceptable braze alloys for these applications are identified along with process, thermal braze cycle data, and thermal management procedures. Shear specimens are used to evaluate comparative shear strength properties for the various alloys at both room and cryogenic (-300 F) temperatures and include the effects of electroless nickel plating. Nickel plating was found to significantly enhance both the wetability and strength properties for the various braze alloys studied. The data are provided for use in selecting braze alloys for use with 18 Ni grade 200 steel in the design of wind tunnel models to be tested in an ambient or cryogenic environment.

  12. [Guidelines for adult diffuse gliomas WHO grade II, III and IV: pathology and biology. Société franc¸aise de neuropathologie . Réseau de neuro-oncologie pathologique].

    Science.gov (United States)

    Figarella-Branger, Dominique; Labrousse, François; Mohktari, Karima

    2012-10-01

    Pathological diagnosis plays a major role in the therapeutic management of adult diffuse gliomas. It is based on the histopathological analysis of a representative specimen. Therefore pathologists might be aware of the neuroradiological features of the lesions. Pathologists play a major role in the management of biological resources. Pathologists should classify adult gliomas according to WHO 2007 classification (histological subtype and grade). In addition, in order to provide the histomolecular classification of adult gliomas, search for molecular markers of diagnostic, prognostic or predictive of therapeutic responses must be performed by appropriate and validated immunohistochemical and molecular techniques. In all diffuse gliomas, whatever their grade, search for IDH1 R132H and P53 expression is required. Search for IDH1 minor mutations and IDH2 mutations is required in grade II and III IDH1 R132H negative gliomas whereas 1p19q codeletion should be searched for in grade II and III gliomas with an oligodendroglial component. Search for EGFR amplification and MGMT promoter methylation is recommended. It is strongly recommended to fill the standardized form for pathology and molecular features (validated by the French Society of Neuropathology) in all adult diffuse gliomas.

  13. Phase III intergroup study of fludarabine phosphate compared with cyclophosphamide, vincristine, and prednisone chemotherapy in newly diagnosed patients with stage II and IV low-grade malignant non-Hodgkin's lymphoma

    NARCIS (Netherlands)

    A. Hagenbeek; H. Eghbali; S. Monfardini; U. Viloto; P.J. Hoskin; C. de Wolf-Peeters; K. MacLennan; E. Staab-Renner; J. Kalmus; A. Schott; I. Teodorovic; A. Negrouk; M. van Glabbeke; R. Marcus

    2006-01-01

    Purpose To compare the efficacy and safety of fludarabine phosphate with cyclophosphamide, vincristine, and prednisone (CVP) in 381 previously untreated, advanced-stage, low-grade (lg) non-Hodgkin's lymphoma (NHL) patients in a phase III, multicenter study. Patients and Methods Between 1993 and 1997

  14. Effect of Modeling Instruction on Concept Knowledge Among Ninth Grade Physics Students

    Science.gov (United States)

    Ditmore, Devin Alan

    A basic knowledge of physics concepts is the gateway to success through high-paying careers in science, technology, engineering, and mathematics (STEM). Many students show little understanding of concepts following traditional physics instruction. As an alternative to current lecture-based approaches for high school physics instruction, Piaget's theory of cognitive development supports using real scientific experiences to lead learners from concrete to formal understanding of complex concepts. Modeling instruction (MI) is a pedagogy that guides learners through genuine scientific experiences. This project study analyzed the effects of MI on 9th grade physics students' gains on the test measuring mastery of physics concepts, Force Concept Inventory (FCI). A quasi-experimental design was used to compare the FCI scores of a traditional lecture-taught control group to a treatment group taught using MI. A t test t(-.201) = 180.26, p = .841 comparing the groups and an analysis of variance F(2,181) = 5.20 comparing female to male students indicated MI had no significant positive effect on students. A partial eta squared of the effect size showed that 5.4% of the variance in FCI gains was accounted for by gender, favoring female participants for both groups. The significant relationship between content and gender bears further inquiry. A lesson plan guide was designed to help teachers use computer simulation technology within the MI curriculum. The project promotes positive social change by exploring further ways to help adolescents experience success in physics at the beginning of high school, leading to future success in all STEM areas.

  15. Nanoindentation of Functionally Graded Polymer Nanocomposites: Assessment of the Strengthening Parameters through Experiments and Modeling

    Science.gov (United States)

    Nardi, Tommaso; Hammerquist, Chad; Nairn, John; Karimi, Ayat; Manson, Jan-Anders; Leterrier, Yves

    2015-08-01

    NNanoindentation tests were carried out on the surface of polymer nanocomposites exhibiting either graded or homogeneous distributions of Fe3O4@silica core-shell nanoparticles in a photocurable polymeric matrix. The results reveal a complex interplay between graded morphology, indentation depth and calculated modulus and hardness values, which was elucidated through numerical simulations. First, it was experimentally shown how for small (1 µm) indentations, large increases in modulus (up to +40%) and hardness (up to +93%) were obtained for graded composites with respect to their homogeneous counterparts, whereas at a larger indentation depth (20 µm) the modulus and hardness of the graded and homogeneous composites did not substantially differ from each other and from those of the pure polymer. Then, through a Material Point Method approach, experimental nanoindentation tests were successfully simulated, confirming the importance of the indentation depth and of the associated plastic zone as key factors for a more accurate design of graded polymer nanocomposites whose mechanical properties are able to fulfill the requirements encountered during operational life.

  16. Nanoindentation of Functionally Graded Polymer Nanocomposites: Assessment of the Strengthening Parameters through Experiments and Modeling

    Directory of Open Access Journals (Sweden)

    Tommaso eNardi

    2015-08-01

    Full Text Available NNanoindentation tests were carried out on the surface of polymer nanocomposites exhibiting either graded or homogeneous distributions of Fe3O4@silica core-shell nanoparticles in a photocurable polymeric matrix. The results reveal a complex interplay between graded morphology, indentation depth and calculated modulus and hardness values, which was elucidated through numerical simulations. First, it was experimentally shown how for small (1 µm indentations, large increases in modulus (up to +40% and hardness (up to +93% were obtained for graded composites with respect to their homogeneous counterparts, whereas at a larger indentation depth (20 µm the modulus and hardness of the graded and homogeneous composites did not substantially differ from each other and from those of the pure polymer. Then, through a Material Point Method approach, experimental nanoindentation tests were successfully simulated, confirming the importance of the indentation depth and of the associated plastic zone as key factors for a more accurate design of graded polymer nanocomposites whose mechanical properties are able to fulfill the requirements encountered during operational life.

  17. Geostatistical modeling of facies, bitumen grade and particle size distribution for the Joslyn oil sand open pit mine project

    Energy Technology Data Exchange (ETDEWEB)

    Babak, Olena; Insalaco, Enzo; Mittler, Andreas [Total EandP Canada Ltd. (Canada)

    2011-07-01

    The Joslyn North Mine Project is currently in the pre-development stage; the aim of this study is to use different available data to draw a geological model of facies, bitumen grade, full particle size distribution (PSD) and ore/waste discrimination. The study was conducted with the database of around 800 wells, stochastic, indicator and Gaussian simulations were performed along with a sensitivity study. Results demonstrated the importance of some parameters for evaluating grade cases including variogram uncertainty, sampling limitations and errors in geostatistical workflow. In addition, modeling the full PSD dataset was shown to be useful. This study demonstrated how to use available database through an overall workflow to develop case scenarios for bitumen in place in ore and characterize the ore material.

  18. Closed-Form Solutions for a Nonlinear Partial Differential Equation Arising in the Study of a Fourth Grade Fluid Model

    Directory of Open Access Journals (Sweden)

    Taha Aziz

    2012-01-01

    Full Text Available The unsteady unidirectional flow of an incompressible fourth grade fluid bounded by a suddenly moved rigid plate is studied. The governing nonlinear higher order partial differential equation for this flow in a semiinfinite domain is modelled. Translational symmetries in variables and are employed to construct two different classes of closed-form travelling wave solutions of the model equation. A conditional symmetry solution of the model equation is also obtained. The physical behavior and the properties of various interesting flow parameters on the structure of the velocity are presented and discussed. In particular, the significance of the rheological effects are mentioned.

  19. Thermodynamic Modeling of Multi-phase Solid–Liquid Equilibria in Industrial-Grade Oils and Fats

    DEFF Research Database (Denmark)

    Hjorth, Jeppe Lindegaard; Miller, Rasmus L.; Woodley, John M.

    2015-01-01

    Compositional thermodynamic phase separation is investigated for industrial-grade vegetable oils with complex compositions. Solid–liquid equilibria have been calculated by utilizing the Margules 2-suffix activity-coefficient model in combination with minimization of the Gibb’s free energy of the ...... because many different oil mixtures can be evaluated quickly with respect to specific properties, prior to more time-consuming experimental evaluation....

  20. Grading Exceptional Learners

    Science.gov (United States)

    Jung, Lee Ann; Guskey, Thomas R.

    2010-01-01

    Teachers often grapple with the challenge of giving report card grades to students with learning disabilities and English language learners. The authors offer a five-step model that "offers a fair, accurate, and legal way to adapt the grading process for exceptional learners." The model begins with a high-quality reporting system for all students…

  1. Prediction Model of Cutting Parameters for Turning High Strength Steel Grade-H: Comparative Study of Regression Model versus ANFIS

    Directory of Open Access Journals (Sweden)

    Adel T. Abbas

    2017-01-01

    Full Text Available The Grade-H high strength steel is used in the manufacturing of many civilian and military products. The procedures of manufacturing these parts have several turning operations. The key factors for the manufacturing of these parts are the accuracy, surface roughness (Ra, and material removal rate (MRR. The production line of these parts contains many CNC turning machines to get good accuracy and repeatability. The manufacturing engineer should fulfill the required surface roughness value according to the design drawing from first trail (otherwise these parts will be rejected as well as keeping his eye on maximum metal removal rate. The rejection of these parts at any processing stage will represent huge problems to any factory because the processing and raw material of these parts are very expensive. In this paper the artificial neural network was used for predicting the surface roughness for different cutting parameters in CNC turning operations. These parameters were investigated to get the minimum surface roughness. In addition, a mathematical model for surface roughness was obtained from the experimental data using a regression analysis method. The experimental data are then compared with both the regression analysis results and ANFIS (Adaptive Network-based Fuzzy Inference System estimations.

  2. Oxidation of 3,6-dioxa-1,8-octanedithiol by platinum(IV) anticancer prodrug and model complex: kinetic and mechanistic studies.

    Science.gov (United States)

    Huo, Shuying; Shen, Shigang; Liu, Dongzhi; Shi, Tiesheng

    2012-06-07

    Thioredoxins are small redox proteins and have the active sites of Cys-Xaa-Yaa-Cys; they are overexpressed by many different cancer cells. Cisplatin and Pt(II) analogues could bind to the active sites and inhibit the activities of the proteins, as demonstrated by other researchers. Platinum(IV) anticancer drugs are often regarded as prodrugs, but their interactions with thioredoxins have not been studied. In this work, 3,6-dioxa-1,8-octanedithiol (dithiol) was chosen as a model compound for the active sites of thioredoxins, and its reactions with cis-[Pt(NH(3))(2)Cl(4)] and trans-[PtCl(2)(CN)(4)](2-) (cisplatin prodrug and a model complex) were studied. The pK(a) values for the dithiol were characterized to be 8.7 ± 0.2 and 9.6 ± 0.2 at 25.0 °C and an ionic strength of 1.0 M. The reaction kinetics was followed by a stopped-flow spectrophotometer over a wide pH range. An overall second-order rate law was established, -d[Pt(IV)]/dt = k'[Pt(IV)][dithiol], where k' stands for the observed second-order rate constants. Values of k' increased several orders of magnitude when the solution pH was increased from 3 to 9. A stoichiometry of Δ[Pt(IV)]/Δ[dithiol] = 1:1 derived for the reduction process and product analysis by mass spectrometry indicated that the dithiol was oxidized to form an intramolecular disulfide, coinciding with the nature of thioredoxin proteins. All of the reaction features are rationalized in terms of a reaction mechanism, involving three parallel rate-determining steps depending on the pH of the reaction medium. Rate constants for the rate-determining steps were evaluated. It can be concluded that Pt(IV) anticancer prodrugs can oxidize the reduced thioredoxins, and the oxidation mechanism is similar to those of the oxidations of biologically important reductants by some reactive oxygen species (ROS) such as hypochlorous acid/hypochlorite and chloramines.

  3. Asphalt Pavement Aging and Temperature Dependent Properties Using Functionally Graded Viscoelastic Model

    Science.gov (United States)

    Dave, Eshan V.

    2009-01-01

    Asphalt concrete pavements are inherently graded viscoelastic structures. Oxidative aging of asphalt binder and temperature cycling due to climatic conditions being the major cause of non-homogeneity. Current pavement analysis and simulation procedures dwell on the use of layered approach to account for these non-homogeneities. The conventional…

  4. Model Planning of Literature Lessons in the Tenth Grade for the 1973/74 School Year

    Science.gov (United States)

    Gromtseva, S. N.

    1976-01-01

    Topics, materials, and assignments are provided for 49 literature lessons for tenth grade, plus review notes. Subject matter includes Gorky, Mayakovsky, Soviet literature in the 1920s, the 1930s, Tolstoi, the Great Patriotic War, Sholokhov, and modern foreign literature. (ND)

  5. Determining Fair Grades for Students with Special Needs: A Standards-Based Model

    Science.gov (United States)

    Jung, Lee Ann; Guskey, Thomas R.

    2007-01-01

    Grades, report cards, and other progress reports are important vehicles for communicating with families about their children's strengths, areas to target, and interventions that can be used at home. For families of children with disabilities, accurate information on learning progress is essential for understanding intervention effectiveness and…

  6. A Networked Learning Model for Construction of Personal Learning Environments in Seventh Grade Life Science

    Science.gov (United States)

    Drexler, Wendy

    2010-01-01

    The purpose of this design-based research case study was to apply a networked learning approach to a seventh grade science class at a public school in the southeastern United States. Students adapted Web applications to construct personal learning environments for in-depth scientific inquiry of poisonous and venomous life forms. API widgets were…

  7. Acids and Bases: The Appropriation of the Arrhenius Model by Tunisian Grade 10 Students

    Science.gov (United States)

    Ouertatani, Latifa; Dumon, Alain; Trabelsi, Malika Ayadi; Soudani, Mohamed

    2007-01-01

    In this work, we propose to identify the knowledge that Tunisian grade 10 students build up concerning acids and bases. Thus, after learning, we have proceeded by giving a paper and pencil task to students of two levels of teaching. The results obtained allow us to say that the assimilated knowledge is transitory; that the students have a worse…

  8. Confirmatory factor analysis of the WAIS-IV/WMS-IV.

    Science.gov (United States)

    Holdnack, James A; Xiaobin Zhou; Larrabee, Glenn J; Millis, Scott R; Salthouse, Timothy A

    2011-06-01

    The Wechsler Adult Intelligence Scale-fourth edition (WAIS-IV) and the Wechsler Memory Scale-fourth edition (WMS-IV) were co-developed to be used individually or as a combined battery of tests. The independent factor structure of each of the tests has been identified; however, the combined factor structure has yet to be determined. Confirmatory factor analysis was applied to the WAIS-IV/WMS-IV Adult battery (i.e., age 16-69 years) co-norming sample (n = 900) to test 13 measurement models. The results indicated that two models fit the data equally well. One model is a seven-factor solution without a hierarchical general ability factor: Verbal Comprehension, Perceptual Reasoning, Processing Speed, Auditory Working Memory, Visual Working Memory, Auditory Memory, and Visual Memory. The second model is a five-factor model composed of Verbal Comprehension, Perceptual Reasoning, Processing Speed, Working Memory, and Memory with a hierarchical general ability factor. Interpretative implications for each model are discussed.

  9. ESCRT-Dependent Cell Death in a Caenorhabditis elegans Model of the Lysosomal Storage Disorder Mucolipidosis Type IV.

    Science.gov (United States)

    Huynh, Julie M; Dang, Hope; Munoz-Tucker, Isabel A; O'Ketch, Marvin; Liu, Ian T; Perno, Savannah; Bhuyan, Natasha; Crain, Allison; Borbon, Ivan; Fares, Hanna

    2016-02-01

    Mutations in MCOLN1, which encodes the cation channel protein TRPML1, result in the neurodegenerative lysosomal storage disorder Mucolipidosis type IV. Mucolipidosis type IV patients show lysosomal dysfunction in many tissues and neuronal cell death. The ortholog of TRPML1 in Caenorhabditis elegans is CUP-5; loss of CUP-5 results in lysosomal dysfunction in many tissues and death of developing intestinal cells that results in embryonic lethality. We previously showed that a null mutation in the ATP-Binding Cassette transporter MRP-4 rescues the lysosomal defect and embryonic lethality of cup-5(null) worms. Here we show that reducing levels of the Endosomal Sorting Complex Required for Transport (ESCRT)-associated proteins DID-2, USP-50, and ALX-1/EGO-2, which mediate the final de-ubiquitination step of integral membrane proteins being sequestered into late endosomes, also almost fully suppresses cup-5(null) mutant lysosomal defects and embryonic lethality. Indeed, we show that MRP-4 protein is hypo-ubiquitinated in the absence of CUP-5 and that reducing levels of ESCRT-associated proteins suppresses this hypo-ubiquitination. Thus, increased ESCRT-associated de-ubiquitinating activity mediates the lysosomal defects and corresponding cell death phenotypes in the absence of CUP-5.

  10. Convergence between DSM-IV-TR and DSM-5 diagnostic models for personality disorder: evaluation of strategies for establishing diagnostic thresholds.

    Science.gov (United States)

    Morey, Leslie C; Skodol, Andrew E

    2013-05-01

    The Personality and Personality Disorders Work Group for the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) recommended substantial revisions to the personality disorders (PDs) section of DSM-IV-TR, proposing a hybrid categorical-dimensional model that represented PDs as combinations of core personality dysfunctions and various configurations of maladaptive personality traits. Although the DSM-5 Task Force endorsed the proposal, the Board of Trustees of the American Psychiatric Association (APA) did not, placing the Work Group's model in DSM-5 Section III ("Emerging Measures and Models") with other concepts thought to be in need of additional research. This paper documents the impact of using this alternative model in a national sample of 337 patients as described by clinicians familiar with their cases. In particular, the analyses focus on alternative strategies considered by the Work Group for deriving decision rules, or diagnostic thresholds, with which to assign categorical diagnoses. Results demonstrate that diagnostic rules could be derived that yielded appreciable correspondence between DSM-IV-TR and proposed DSM-5 PD diagnoses-correspondence greater than that observed in the transition between DSM-III and DSM-III-R PDs. The approach also represents the most comprehensive attempt to date to provide conceptual and empirical justification for diagnostic thresholds utilized within the DSM PDs.

  11. Grade-Tonnage, Ore Value-Tonnage, and Enrichment Ratio-Tonnage Models for Resource Assessment

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    According to grade-tonnage diagrams of nickel and zinc deposits, their critical grades are 0.4 % and 3.4 %, respectively, and hence the former resources can be considered optimistic and the latter pessimistic. The grade-tonnage diagram of gold deposits is convex downwards suggesting that the critical grade is 1×10-6 in the low-grade part. The ore value (OV)-tonnage diagram of all deposits in the world consists of three parts: high, middle and low value classes. The enrichment ratio (ER)-tonnage diagram of all deposits in the world also consists of three parts: high, middle and low ratio classes. Nine quality categories defined by ER and OV are characterized by some keywords indicating deposit types as follows: category HH (high ER-high OV: 0.7 %) by “unconformity” and “Mississippi Valley”, category HM (high ER-middle OV: 0.7 %) by “vein”, category ML (middle ER-low OV: 0 %) by “sandstone”, “stockwork” and “dissemination”, category LM by “orthomagmatic”, “laterite”, komatiite“ and ”chemical“, and category LL by “porphyry”, “dissemination” and “placer”. Category MM is not characterized by any keyword. If the commodities of a deposit are defined by both the enrichment ratio and the ore value, the defined commodities are relatively coincident for gold and nickel, but different for copper, silver and zinc, and greatly different for molybdenum and lead. Deposits containing lead and/or zinc are complimentary. If the commodity Pb+Zn is applied, most lead or zinc deposits are classified as Pb+Zn by both definitions. Accessory metals are commonly expected for deposits of kuroko-type zinc, epithermal silver, massive sulfide-type zinc and volcanogenic zinc, but uncommon for deposits of orthomagmatic chromium, chemically precipitated copper and sandstone-type uranium.

  12. The Effect of the Van Hiele Model Based Instruction on the Creative Thinking Levels of 6th Grade Primary School Students

    Science.gov (United States)

    Erdogan, Tolga; Akkaya, Recai; Celebi Akkaya, Sibel

    2009-01-01

    The aim of this study is to determine the effect of the Van Hiele model based instruction process on the creative thinking levels of 6th grade primary school students. Pre test-post test matching control group quasi-experimental design was used in the study. Fifty five students enrolled in sixth grades during the 2005-2006 educational year formed…

  13. Is the Whole Greater than the Sum of Its Parts? Modeling the Contributions of Language Comprehension Skills to Reading Comprehension in the Upper Elementary Grades

    Science.gov (United States)

    Kieffer, Michael J.; Petscher, Yaacov; Proctor, C. Patrick; Silverman, Rebecca D.

    2016-01-01

    Language comprehension is crucial to reading. However, theoretical models and recent research raise questions about what constitutes this multifaceted domain. We present two related studies examining the dimensionality of language comprehension and relations to reading comprehension in the upper elementary grades. Studies 1 (Grade 6; N = 148) and…

  14. Is the Whole Greater than the Sum of Its Parts? Modeling the Contributions of Language Comprehension Skills to Reading Comprehension in the Upper Elementary Grades

    Science.gov (United States)

    Kieffer, Michael J.; Petscher, Yaacov; Proctor, C. Patrick; Silverman, Rebecca D.

    2016-01-01

    Language comprehension is crucial to reading. However, theoretical models and recent research raise questions about what constitutes this multifaceted domain. We present two related studies examining the dimensionality of language comprehension and relations to reading comprehension in the upper elementary grades. Studies 1 (Grade 6; N = 148) and…

  15. Diagnostic Value Resulting from the IRT Modeling of IGAP Reading Data: Using A Graded Response Model To Retrieve and Utilize More Information.

    Science.gov (United States)

    Evans, John Andrew; Ackerman, Terry

    The strengths of item-response theory (IRT) are used to examine the degree of information individual test items provide, as well as to investigate how the individual item types contribute to the overall measurement accuracy of the Illinois Goal Assessment Program (IGAP) reading test. Using the graded-response model of Samejima (1969), the amount…

  16. Finite Element Modeling and Free Vibration Analysis of Functionally Graded Nanocomposite Beams Reinforced by Randomly Oriented Carbon Nanotubes

    Directory of Open Access Journals (Sweden)

    Benedict Thomas

    2013-12-01

    Full Text Available This article deals with the finite element modeling and free vibration analysis of functionally graded nanocomposite beams reinforced by randomly oriented straight single-walled carbon nanotubes (SWCNTs. Nanostructural materials can be used to alter mechanical, thermal and electrical properties of polymer-based composite materials, because of their superior properties and perfect atom arrangement. Timoshenko beam theory is used to evaluate dynamic characteristics of the beam. The Eshelby–Mori–Tanaka approach based on an equivalent fiber is used to investigate the material properties of the beam. The equations of motion are derived by using Hamilton’s principle. The finite element method is employed to discretize the model and obtain a numerical approximation of the motion equation. Different SWCNTs distributions in the thickness direction are introduced to improve fundamental natural frequency and dynamic behavior of uniform functionally graded nanocomposite beam. Results are presented in tabular and graphical forms to show the effects of various material distributions, carbon nanotube orientations, shear deformation, slenderness ratios and boundary conditions on the dynamic behavior of the beam. The first five normalized mode shapes for functionally graded carbon nanotube reinforced composite (FG-CNTRC beams with different boundary conditions and different carbon nanotubes (CNTs orientation are presented. The results show that the above mentioned effects play very important role on the dynamic behavior of the beam.

  17. The Bohr Model and the Fifth Grade: A New Standards-Based Hands-On Physics Curriculum

    Science.gov (United States)

    Brock, Jeff; Springer, Russell; Goldberg, Bennett

    2004-03-01

    A semester-long, standards-based, hands-on physics curriculum appropriate for the fifth grade was developed. Previously available curricula were successful in using hands-on activities to teach basic fifth-grade physics skills and concepts, but did not attempt to foster understanding of the fundamental underlying physics. We expanded the role of inquiry-based instruction to expose students to the fundamental physics behind electricity, forces, energy, light and sound. Central to the course, the Bohr model of the atom was used as a key tool both to motivate exploration of these topics as well as to develop basic conceptual understanding of fundamental ideas in quantum and electromagnetic physics. The curriculum was designed to be compatible with both district and state-mandated standards in a high-stakes test environment. This work was supported by NSF grant DGE-0231909.

  18. Drying of a tape-cast layer: Numerical modelling of the evaporation process in a graded/layered material

    DEFF Research Database (Denmark)

    Jabbaribehnam, Mirmasoud; Jambhekar, V. A.; Hattel, Jesper Henri;

    2016-01-01

    Evaporation of water from a ceramic layer is a key phenomenon in the drying process for the manufacturing of water-based tape cast ceramics. In this paper we present a coupled free-flow-porous-media model on the Representative Elementary Volume (REV) scale for coupling non-isothermal multi...... in accordance with the available results from the literature. We elaborate on and discuss the characteristic drying-rate curve for a single layer ceramic, and compare it with that of a graded/layered ceramic. We, moreover, show the influence of the mean diameter of particles of the porous medium (dp) — which...... directly affects the intrinsic permeability (K) based on the well-known Ergun's equation — of each single ceramic layer on the drying behaviour of a graded/layered ceramic....

  19. High-temperature thermo-mechanical behavior of functionally graded materials produced by plasma sprayed coating: Experimental and modeling results

    Science.gov (United States)

    Choi, Kang Hyun; Kim, Hyun-Su; Park, Chang Hyun; Kim, Gon-Ho; Baik, Kyoung Ho; Lee, Sung Ho; Kim, Taehyung; Kim, Hyoung Seop

    2016-09-01

    Thermal barrier coatings are widely used in aerospace industries to protect exterior surfaces from harsh environments. In this study, functionally graded materials (FGMs) were investigated with the aim to optimize their high temperature resistance and strength characteristics. NiCrAlY bond coats were deposited on Inconel-617 superalloy substrate specimens by the low vacuum plasma spraying technique. Functionally graded Ni-yttria-stabilized zirconia (YSZ) coatings with gradually varying amounts of YSZ (20%-100%) were fabricated from composite powders by vacuum plasma spraying. Heat shield performance tests were conducted using a high- temperature plasma torch. The temperature distributions were measured using thermocouples at the interfaces of the FGM layers during the tests. A model for predicting the temperature at the bond coating-substrate interface was established. The temperature distributions simulated using the finite element method agreed well with the experimental results.

  20. Pu(V) transport through Savannah River Site soils - an evaluation of a conceptual model of surface- mediated reduction to Pu (IV).

    Science.gov (United States)

    Powell, Brian A; Kaplan, Daniel I; Serkiz, Steven M; Coates, John T; Fjeld, Robert A

    2014-05-01

    Over the last fifteen years the Savannah River Site (SRS) in South Carolina, USA, was selected as the site of three new plutonium facilities: the Mixed Oxide Fuel Fabrication Facility, Pit Disassembly and Conversion Facility, and the Pu Immobilization Plant. In order to assess the potential human and environmental risk associated with these recent initiatives, improved understanding of the fate and transport of Pu in the SRS subsurface environment is necessary. The hypothesis of this study was that the more mobile forms of Pu, Pu(V) and Pu(VI), would be reduced to the less mobile Pu(III/IV) oxidation states under ambient SRS subsurface conditions. Laboratory-scale dynamic flow experiments (i.e., column studies) indicated that Pu(V) was very mobile in SRS sediments. At higher pH values the mobility of Pu decreased and the fraction of Pu that became irreversibly sorbed to the sediment increased, albeit, only slightly. Conversely, these column experiments showed that Pu(IV) was essentially immobile and was largely irreversibly sorbed to the sediment. More than 100 batch sorption experiments were also conducted with four end-member sediments, i.e., sediments that include the chemical, textural, and mineralogical properties likely to exist in the SRS. These tests were conducted as a function of initial Pu oxidation state, pH, and contact time and consistently demonstrated that although Pu(V) sorbed initially quite weakly to sediments, it slowly, over the course of Pu(IV). This is consistent with our hypothesis that Pu(V) is reduced to the more strongly sorbing form of Pu, Pu(IV). These studies provide important experimental support for a conceptual geochemical model for dissolved Pu in a highly weathered subsurface environment. That is that, irrespective of the initial oxidation state of the dissolved Pu introduced into a SRS sediment system, Pu(IV) controls the environmental transport within a couple weeks and Pu strongly binds to the sediment, limiting its mobility.

  1. Progression-free survival: an important end point in evaluating therapy for recurrent high-grade gliomas.

    Science.gov (United States)

    Lamborn, Kathleen R; Yung, W K Alfred; Chang, Susan M; Wen, Patrick Y; Cloughesy, Timothy F; DeAngelis, Lisa M; Robins, H Ian; Lieberman, Frank S; Fine, Howard A; Fink, Karen L; Junck, Larry; Abrey, Lauren; Gilbert, Mark R; Mehta, Minesh; Kuhn, John G; Aldape, Kenneth D; Hibberts, Janelle; Peterson, Pamela M; Prados, Michael D

    2008-04-01

    The North American Brain Tumor Consortium (NABTC) uses 6-month progression-free survival (6moPFS) as the efficacy end point of therapy trials for adult patients with recurrent high-grade gliomas. In this study, we investigated whether progression status at 6 months predicts survival from that time, implying the potential for prolonged survival if progression could be delayed. We also evaluated earlier time points to determine whether the time of progression assessment alters the strength of the prediction. Data were from 596 patient enrollments (159 with grade III gliomas and 437 with grade IV tumors) in NABTC phase II protocols between February 1998 and December 2002. Outcome was assessed statistically using Kaplan-Meier curves and Cox proportional hazards models. Median survivals were 39 and 30 weeks for patients with grade III and grade IV tumors, respectively. Twenty-eight percent of patients with grade III and 16% of patients with grade IV tumors had progression-free survival of >26 weeks. Progression status at 9, 18, and 26 weeks predicted survival from those times for patients with grade III or grade IV tumors (p < 0.001 and hazard ratios < 0.5 in all cases). Including KPS, age, number of prior chemotherapies, and response in a multivariate model did not substantively change the results. Progression status at 6 months is a strong predictor of survival, and 6moPFS is a valid end point for trials of therapy for recurrent malignant glioma. Earlier assessments of progression status also predicted survival and may be incorporated in the design of future clinical trials.

  2. Material and Thickness Grading for Aeroelastic Tailoring of the Common Research Model Wing Box

    Science.gov (United States)

    Stanford, Bret K.; Jutte, Christine V.

    2014-01-01

    This work quantifies the potential aeroelastic benefits of tailoring a full-scale wing box structure using tailored thickness distributions, material distributions, or both simultaneously. These tailoring schemes are considered for the wing skins, the spars, and the ribs. Material grading utilizes a spatially-continuous blend of two metals: Al and Al+SiC. Thicknesses and material fraction variables are specified at the 4 corners of the wing box, and a bilinear interpolation is used to compute these parameters for the interior of the planform. Pareto fronts detailing the conflict between static aeroelastic stresses and dynamic flutter boundaries are computed with a genetic algorithm. In some cases, a true material grading is found to be superior to a single-material structure.

  3. THE EFFECT OF PICURE STORY VIDEO MEDIA ON THE SPEAKING SKILLS IMPROVEMENT OF CHILDREN WITH INTELLECTUAL CHALLENGES AT GRADE IV SPECIAL EDUCATION SCHOOL CLASS C (SPLB-C OF CIPAGANTI SPECIAL EDUCATION FOUNDATION (YPLB CIPAGANTI

    Directory of Open Access Journals (Sweden)

    Nia Sutisna

    2015-06-01

    Masalah yang ditemukan pada anak tunagrahita yaitu berkaitan dengan hambatan berkomunikasi atau mengembangkan kemampuan bahasa lisan/berbicara sesuai dengan norma lingkungan dan dapat menangkap perasan dan gagasan lawan bicara serta berperan aktif dalam lingkungan. Untuk merealisasikan usaha tersebut perlu adanya latihan berbicara atau speech education yaitu melalui media video cerita yang memadai dan bentuk kegiatan yang menunjang. berdasarkan latar belakang masalah tersebut timbullah sebuah rumusan masalah dalam penelitian ini, yaitu: “Adakah pengaruh penggunaan media cerita bergambar terhadap peningkatan kemampuan berbicara Anak Tunagrahita Ringan?” Dalam menjawab permasalahan penelitian tersebut, peneliti menggunakan metode eksperimen dengan bentuk One Group Pre test Post test Design uji Wilcoxon. Adapun subjek dalam penelitian ini adalah empat orang siswa tunagrahita kelas IV SPLB-C YPLB Cipaganti Kata kunci: media video, tunagrahita, kemampuan berbicara

  4. Modeling of Teaching 5th-7th-Grade Boys Physical Exercises

    Directory of Open Access Journals (Sweden)

    Т. Г. Абдулхалікова

    2017-09-01

    Full Text Available The research objective is to determine the effectiveness of orthogonal variants of teaching 5th-7th graders physical exercises. Materials and methods. The participants in the research were boys of the 5th grade (n = 32, 6th grade (n = 40, 7th grade (n = 52. To achieve the tasks set, the research used the following methods: analysis of scientific and methodological literature; pedagogical testing, pedagogical observation, timing of educational tasks; pedagogical experiment, medical and biological research methods; methods of mathematical statistics, methods of mathematical experiment planning. In order to achieve the objective set, the research has studied the effect of different variants of the educational process structure, namely: the number of repetitions (х1 and rest intervals (х2 when learning the technique of performing physical exercises. The research has conducted a complete factor experiment of type 22. According to the experiment plan, the 5th-7th graders were divided into training groups. In total, there were 12 experimental groups organized. Research results. The analysis of the regression equations shows that the teaching of physical exercises to the 5th-7th-grade boys is mostly influenced by rest intervals between repetitions (х2. The number of repetitions (х1 has somewhat less influence. The interaction of these factors is insignificant when teaching physical exercises and becomes much more influential only when teaching a switch leg pull-over exercise (х1х2. Conclusions. To increase the effectiveness of teaching 5th-7th graders physical exercises, it is necessary to shorten rest intervals between repetition to 60 s and to reduce the number of repetitions to six. When teaching boys the switch leg pull-over exercise, rest intervals should be increased to 120 s and the number of repetitions — to twelve.

  5. In Vitro Models in BiocompatibilityAssessment for Biomedical-Grade Chitosan Derivatives in Wound Management

    Directory of Open Access Journals (Sweden)

    Lim Chin Keong

    2009-03-01

    Full Text Available One of the ultimate goals of wound healing research is to find effective healing techniques that utilize the regeneration of similar tissues. This involves the modification of various wound dressing biomaterials for proper wound management. The biopolymer chitosan (b-1,4-D-glucosamine has natural biocompatibility and biodegradability that render it suitable for wound management. By definition, a biocompatible biomaterial does not have toxic or injurious effects on biological systems. Chemical and physical modifications of chitosan influence its biocompatibility and biodegradability to an uncertain degree. Hence, the modified biomedical-grade of chitosan derivatives should be pre-examined in vitro in order to produce high-quality, biocompatible dressings. In vitro toxicity examinations are more favorable than those performed in vivo, as the results are more reproducible and predictive. In this paper, basic in vitro tools were used to evaluate cellular and molecular responses with regard to the biocompatibility of biomedical-grade chitosan. Three paramount experimental parameters of biocompatibility in vitro namely cytocompatibility, genotoxicity and skin pro-inflammatory cytokine expression, were generally reviewed for biomedical-grade chitosan as wound dressing.

  6. APPLYING PPE MODEL BASED ON RAGA TO CLASSIFY AND EVALUATE SOIL GRADE

    Institute of Scientific and Technical Information of China (English)

    FUQiang; LUTie-guang; 等

    2002-01-01

    The research of soil classification and soil grade evaluation is often based on fuzzy theory .So ,the tradition-al method has an inevitable problem about weight matrix which given by some experts ,and the final result can be influ-enced by artificial factors.The essentials of fuzzy synthetically judge is to handle the data of high dimension.That is to reducing the dimension number.The weight matrix in fuzzy theory is corresponding to low dimension projection value of each index.But we canˊt define whether the weight matrix given by experts is the best projection value or not.So,the authors apply a new technique of falling dimension named projection pursuit to soil study,through using the improved re-al coding based accelerating genetic algorithm to optimize the projection direction.Thus,it can transfer multi-dimension data into one dimension data,through searching for the optimum projection direction to realize the soil classification and its grade evaluation.The method can avoid the artificial disturbance,and acquire preferably effect.Thus,the paper pro-vides a new method to the research of soil classification and grade evaluation.

  7. APPLYING PPE MODEL BASED ON RAGA TO CLASSIFY AND EVALUATE SOIL GRADE

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The research of soil classification and soil grade evaluation is often based on fuzzy theory. So, the traditional method has an inevitable problem about weight matrix which given by some experts, and the final result can be influenced by artificial factors. The essentials of fuzzy synthetically judge is to handle the data of high dimension. That is to reducing the dimension number. The weight matrix in fuzzy theory is corresponding to low dimension projection value of each index. But we can′ t define whether the weight matrix given by experts is the best projection value or not. So, the authors apply a new technique of falling dimension named projection pursuit to soil study, through using the improved real coding based accelerating genetic algorithm to optimize the projection direction. Thus, it can transfer multi-dimension data into one dimension data, through searching for the optimum projection direction to realize the soil classification and its grade evaluation. The method can avoid the artificial disturbance, and acquire preferably effect. Thus, the paper provides a new method to the research of soil classification and grade evaluation.

  8. Oxovanadium(IV complexes of bioinorganic and medicinal relevance: Synthesis, characterization and 3D molecular modeling of some oxovanadium(IV complexes involving O, N-donor environment of salicylaldehyde-based sulfa drug Schiff bases

    Directory of Open Access Journals (Sweden)

    R.C. Maurya

    2016-11-01

    Full Text Available The present paper reports the synthesis and characterization of some new sulfa drug based Schiff base oxovanadium(IV complexes of composition, [VO(sal-sdz2(H2O]·H2O, [VO(sal-sgn2(H2O]·H2O, [VO(sal-snm(H2O]·H2O, [VO(sal-smr2(H2O]·H2O and [VO(dadps(H2O]2·2H2O, where sal-sdzH = N-(salicylidenesulfadizine, sal-sgnH = N-(salicylidenesulfaguanidine, sal-snmH = N-(salicylidenesulfanilamide, sal-smrH = N-(salicylidenesulfamerizine, sal-dadpsH2 = N,N′-bis(salicylidene-4,4′-diaminodiphenylsulfone, respectively. Complexes, (1–(4 were prepared by the reaction of VOSO4·5H2O with the Schiff bases in 1:2 metal-ligand ratio while complex (5 in 2:2 metal-ligand ratio in DMF-ethanol medium. The compounds so obtained were characterized by different physico-chemical studies, such as, elemental analysis, molar conductance and magnetic measurements, infrared, ESR, thermogravimetric studies, mass and electronic spectral studies. The overall IR studies conclude that the ligand in complex (1–(4 behave as monobasic bidentate ON donor, while the ligand in the complex (5 behaves as dibasic tetradentate O2N2 donor. The 3D-molecular modeling and analysis for bond lengths and bond angles have also been carried out for two representative compounds, [VO(sal-snm2(H2O]·H2O (3 and [VO(dadps(H2O]2·2H2O (5 to substantiate the proposed structures. Based on these studies suitable octahedral structures have been proposed for these complexes.

  9. DECOVALEX_IV TASK_D项目的热-水-力耦合过程的数值模拟%NUMERICAL MODELLING AND SIMULATION OF COUPLED THM PROCESSES IN TASK_D OF DECOVALEX_IV

    Institute of Scientific and Technical Information of China (English)

    刘泉声; 张程远; 刘小燕

    2006-01-01

    The purposes of the DECOVALEX project(development of coupled models and their validation against experiments) are focused on the various coupled thermo-hydro-mechanical(THM) and geochemical processes occurring in the near field of a high activity radioactive waste disposal facility,of a demonstration for the feasibility of the construction of engineered barriers,and of how they affect the role of performance assessment for radioactive waste disposal. Task_D of the DECOVALEX_IV project includes predictive analysis of the long-term coupled processes(up to 1×104 years) in two generic repositories--FEBEX type and Yucca Mountain Project type for comparison. To better understand the coupling THM processes and their influences on the system behaviours,this paper presents a rigorous treatment of the theory of non-isothermal flow and deformation in unsaturated porous media. The governing equations based on the conservation equations of mass and energy and the equations of equilibrium,Darcy's law,Fourier's law are derived by using a systematic macroscopic approach. Each of the three phases(solid,liquid and gas) is viewed as an independent continuum,endowed with its own kinematics. Four constituents(solid,water,vapour and dry air) are identified. Four separate but overlapping models are developed as follows:(1) deformation model for solid considering the fluid effective stress,thermal stress,and bentonite saturation swelling pressure;(2) flow model for water and gas considering the mass exchange between water and vapour in evaporation or condensation processes;(3) vapour molecular diffusion and advection model considering the relative movement of vapour to dry air in presumed homogenous pore gas phase;and (4) heat transfer model considering the non-equilibrium local thermal processes that three phases are not at a same temperature. Based on above equations,practical models are developed according to the given Task_D BMT(bench mark test) request,and the codes are programmed

  10. VenUS IV (Venous leg Ulcer Study IV) - compression hosiery compared with compression bandaging in the treatment of venous leg ulcers: a randomised controlled trial, mixed-treatment comparison and decision-analytic model.

    Science.gov (United States)

    Ashby, Rebecca L; Gabe, Rhian; Ali, Shehzad; Saramago, Pedro; Chuang, Ling-Hsiang; Adderley, Una; Bland, J Martin; Cullum, Nicky A; Dumville, Jo C; Iglesias, Cynthia P; Kang'ombe, Arthur R; Soares, Marta O; Stubbs, Nikki C; Torgerson, David J

    2014-09-01

    Compression is an effective and recommended treatment for venous leg ulcers. Although the four-layer bandage (4LB) is regarded as the gold standard compression system, it is recognised that the amount of compression delivered might be compromised by poor application technique. Also the bulky nature of the bandages might reduce ankle or leg mobility and make the wearing of shoes difficult. Two-layer compression hosiery systems are now available for the treatment of venous leg ulcers. Two-layer hosiery (HH) may be advantageous, as it has reduced bulk, which might enhance ankle or leg mobility and patient adherence. Some patients can also remove and reapply two-layer hosiery, which may encourage self-management and could reduce costs. However, little robust evidence exists about the effectiveness of two-layer hosiery for ulcer healing and no previous trials have compared two-layer hosiery delivering 'high' compression with the 4LB. Part I To compare the clinical effectiveness and cost-effectiveness of HH and 4LB in terms of time to complete healing of venous leg ulcers. Part II To synthesise the relative effectiveness evidence (for ulcer healing) of high-compression treatments for venous leg ulcers using a mixed-treatment comparison (MTC). Part III To construct a decision-analytic model to assess the cost-effectiveness of high-compression treatments for venous leg ulcers. Part I A multicentred, pragmatic, two-arm, parallel, open randomised controlled trial (RCT) with an economic evaluation. Part II MTC using all relevant RCT data - including Venous leg Ulcer Study IV (VenUS IV). Part III A decision-analytic Markov model. Part I Community nurse teams or services, general practitioner practices, leg ulcer clinics, tissue viability clinics or services and wound clinics within England and Northern Ireland. Part I Patients aged ≥ 18 years with a venous leg ulcer, who were willing and able to tolerate high compression. Part I Participants in the

  11. Prognostic Gleason grade grouping: data based on the modified Gleason scoring system

    Science.gov (United States)

    Pierorazio, Phillip M.; Walsh, Patrick C.; Partin, Alan W.; Epstein, Jonathan I.

    2014-01-01

    Objective • To investigate pathological and short-term outcomes since the most recent Gleason system modifications by the International Society of Urological Pathology (ISUP) in an attempt to divide the current Gleason grading system into prognostically accurate Gleason grade groups. Patients and Methods • We queried the Johns Hopkins Radical Prostatectomy Database (1982–2011), approved by the institutional review board, for men undergoing radical prostatectomy (RP) without a tertiary pattern since 2004 and identified 7869 men. • Multivariable models were created using preoperative and postoperative variables; prognostic grade group (Gleason grade ≤6; 3 + 4; 4 + 3; 8; 9–10) was among the strongest predictors of biochemical recurrence-free (BFS) survival. Results • Significant differences were noted among the Gleason grade groups at biopsy; differences were noted in the race, PSA level, clinical stage, number of positive cores at biopsy and the maximum percentage of positive cores among the Gleason grade groups at RP. • With a median (range) follow-up of 2 (1–7) years, 5-year BFS rates for men with Gleason grade ≤6, 3 + 4, 4 + 3, 8 and 9–10 tumours at biopsy were 94.6, 82.7, 65.1, 63.1 and 34.5%, respectively (P ISUP modifications to the Gleason grading system for prostate carcinoma accurately categorize patients by pathological findings and short-term biochemical outcomes but, while retaining the essence of the Gleason system, there is a need for a change in its reporting to more closely reflect tumour behaviour. • We propose reporting Gleason grades, including prognostic grade groups which accurately reflect prognosis as follows: Gleason score ≤6 (prognostic grade group I); Gleason score 3+4=7 (prognostic grade group II); Gleason score 4+3=7 (prognostic grade group III); Gleason score 4+4=8 (prognostic grade group (IV); and Gleason score 9–10 (prognostic grade group (V). PMID:23464824

  12. Implications of a Cognitive Science Model Integrating Literacy in Science on Achievement in Science and Reading: Direct Effects in Grades 3-5 with Transfer to Grades 6-7

    Science.gov (United States)

    Romance, Nancy; Vitale, Michael

    2017-01-01

    Reported are the results of a multiyear study in which reading comprehension and writing were integrated within an in-depth science instructional model (Science IDEAS) in daily 1.5 to 2 h daily lessons on a schoolwide basis in grades 3-4-5. Multilevel (HLM7) achievement findings showed the experimental intervention resulted in significant and…

  13. Stochastic modelling of slow-progressing tumors: Analysis and applications to the cell interplay and control of low grade gliomas

    Science.gov (United States)

    Rodríguez, Clara Rojas; Fernández Calvo, Gabriel; Ramis-Conde, Ignacio; Belmonte-Beitia, Juan

    2017-08-01

    Tumor-normal cell interplay defines the course of a neoplastic malignancy. The outcome of this dual relation is the ultimate prevailing of one of the cells and the death or retreat of the other. In this paper we study the mathematical principles that underlay one important scenario: that of slow-progressing cancers. For this, we develop, within a stochastic framework, a mathematical model to account for tumor-normal cell interaction in such a clinically relevant situation and derive a number of deterministic approximations from the stochastic model. We consider in detail the existence and uniqueness of the solutions of the deterministic model and study the stability analysis. We then focus our model to the specific case of low grade gliomas, where we introduce an optimal control problem for different objective functionals under the administration of chemotherapy. We derive the conditions for which singular and bang-bang control exist and calculate the optimal control and states.

  14. Integration of the WJ IV, WISC-V, WISC-V Integrated, and WIAT-III into a School Neuropsychological Assessment Model

    Science.gov (United States)

    Miller, Daniel C.

    2015-01-01

    The Woodcock-Johnson-Fourth edition (WJ IV; Schrank, McGrew, & Mather, 2014a) and the Wechsler Intelligence Scale for Children-Fifth edition (WISC-V; Wechsler, 2014) are two of the major tests of cognitive abilities used in school psychology. The complete WJ IV battery includes the Woodcock-Johnson IV Tests of Cognitive Abilities (Schrank,…

  15. The Research on the Grade-Category Evaluation Model of Urban Landscape Characteristic

    Institute of Scientific and Technical Information of China (English)

    LI Chun-ling; YU Bo-chun

    2011-01-01

    Landscape Characteristic is a kind of flexible system which has a framework and forms with many elements as a structuralist structure.As the object of study in a regional or a plurality of regions and even the city of a construction unit or a plurality of construction unit landscape features have two dimensions properties,Landscape Characteristic Category and the Landscape Characteristic Grade of the Category(Yu-bochun,2008).Obviously,we can determine the Landscape Characteristic of a certain object on the strength of the two demensions.

  16. Modeling of the interface behavior in tape casting of functionally graded ceramics for magnetic refrigeration parts

    DEFF Research Database (Denmark)

    Jabbari, Masoud; Spangenberg, Jon; Hattel, Jesper Henri

    2013-01-01

    of a graded configuration of the magnetocaloric materials. The Newtonian flow behavior with relatively high viscosity is assumed for each fluid and used in the simulation with a commercial CFD code (ANSYS FLUENT). The results show that the density difference does not affect the interface between the adjacent...... fluids, whereas the viscosity of the fluids plays the most important role in the behavior of the interface. Moreover, increasing the viscosity difference of the adjacent fluids, Δμ, leads to increasing the diffusive region between them. However, this can be counteracted by decreasing the velocity...

  17. East Meets West: Rome. Grade 6 Model Lesson for Unit V. California History-Social Science Course Models.

    Science.gov (United States)

    Zachlod, Michelle, Ed.

    This unit for sixth-grade students provides a fuller understanding of Julius Caesar's significance. Before students delve into the sample topic, they need an understanding of Roman values, lore, republican ideals, and structure of early Roman history. The first few activities in this lesson are to be taught prior to beginning the actual study of…

  18. East Meets West: Rome. Grade 6 Model Lesson for Unit V. California History-Social Science Course Models.

    Science.gov (United States)

    Zachlod, Michelle, Ed.

    This unit for sixth-grade students provides a fuller understanding of Julius Caesar's significance. Before students delve into the sample topic, they need an understanding of Roman values, lore, republican ideals, and structure of early Roman history. The first few activities in this lesson are to be taught prior to beginning the actual study of…

  19. Hamiltonian analysis of a Green-Schwarz sigma model on a supercoset target with Z4m grading

    Institute of Scientific and Technical Information of China (English)

    KE San-Min; YANG Wen-Li; WANG Chun; WANG Zhan-Yun

    2011-01-01

    We perform a Hamiltonian analysis of the Green-Schwarz sigma model on a supercoset target with Z4m grading.The fundamental Poisson brackets between the spatial component of the fiat currents depending on a continuous parameter,which can be thought of as a first step in the complete calculation of the algebra of the transition matrices,are obtained.When m =1,our results are reduced to the results of the type ⅡB Green-Schwarz superstring on AdS5 × S5 background obtained by Das,Melikyan and Sato.

  20. Shock Wave Solutions for Some Nonlinear Flow Models Arising in the Study of a Non-Newtonian Third Grade Fluid

    Directory of Open Access Journals (Sweden)

    Taha Aziz

    2013-01-01

    Full Text Available This study is based upon constructing a new class of closed-form shock wave solutions for some nonlinear problems arising in the study of a third grade fluid model. The Lie symmetry reduction technique has been employed to reduce the governing nonlinear partial differential equations into nonlinear ordinary differential equations. The reduced equations are then solved analytically, and the shock wave solutions are constructed. The conditions on the physical parameters of the flow problems also fall out naturally in the process of the derivation of the solutions.

  1. External validation of bifactor model of ADHD: explaining heterogeneity in psychiatric comorbidity, cognitive control, and personality trait profiles within DSM-IV ADHD.

    Science.gov (United States)

    Martel, Michelle M; Roberts, Bethan; Gremillion, Monica; von Eye, Alexander; Nigg, Joel T

    2011-11-01

    The current paper provides external validation of the bifactor model of ADHD by examining associations between ADHD latent factor/profile scores and external validation indices. 548 children (321 boys; 302 with ADHD), 6 to 18 years old, recruited from the community participated in a comprehensive diagnostic procedure. Mothers completed the Child Behavior Checklist, Early Adolescent Temperament Questionnaire, and California Q-Sort. Children completed the Stop and Trail-Making Task. Specific inattention was associated with depression/withdrawal, slower cognitive task performance, introversion, agreeableness, and high reactive control; specific hyperactivity-impulsivity was associated with rule-breaking/aggressive behavior, social problems, errors during set-shifting, extraversion, disagreeableness, and low reactive control. It is concluded that the bifactor model provides better explanation of heterogeneity within ADHD than DSM-IV ADHD symptom counts or subtypes.

  2. Kinetics and mechanism of oxidation of the anti-tubercular prodrug isoniazid and its analog by iridium(iv) as models for biological redox systems.

    Science.gov (United States)

    Dong, Jingran; Ren, Yanli; Sun, Sufang; Yang, Jiao; Nan, Chunxia; Shi, Hongmei; Xu, Jianzhong; Duan, Jie; Shi, Tiesheng; Elding, Lars I

    2017-07-04

    A complex reaction mechanism of oxidation of the anti-tubercular prodrug isoniazid (isonicotinic hydrazide, INH) by [IrCl6](2-) as a model for redox processes of such drugs in biological systems has been studied in aqueous solution as a function of pH between 0 and 8.5. Similar experiments have been performed with its isomer nicotinic hydrazide (NH). All reactions are overall second-order, first-order in [IrCl6](2-) and hydrazide, and the observed second-order rate constants k' have been determined as a function of pH. Spectrophotometric titrations indicate a stoichiometry of [Ir(iv)] : [hydrazide] = 4 : 1. HPLC analysis shows that the oxidation product of INH is isonicotinic acid. The derived reaction mechanism, based on rate law, time-resolved spectra and stoichiometry, involves parallel attacks by [IrCl6](2-) on all four protolytic species of INH and NH as rate-determining steps, depending on pH. These steps are proposed to generate two types of hydrazyl free radicals. These radicals react further in three rapid consecutive processes, leading to the final oxidation products. Rate constants for the rate-determining steps have been determined for all protolytic species I-IV of INH and NH. They are used to calculate reactivity-pH diagrams. These diagrams demonstrate that for both systems, species IV is ca. 10(5) times more reactive in the redox process than the predominant species III at the physiological pH of 7.4. Thus, species IV will be the main reactant, in spite of the fact that its concentration at this pH is extremely low, a fact that has not been considered in previous work. The results indicate that pH changes might be an important factor in the activation process of INH in biological systems also, and that in such systems this process most likely is more complicated than previously assumed.

  3. Zebrafish as a model for apolipoprotein biology: comprehensive expression analysis and a role for ApoA-IV in regulating food intake

    Directory of Open Access Journals (Sweden)

    Jessica P. Otis

    2015-03-01

    Full Text Available Improved understanding of lipoproteins, particles that transport lipids throughout the circulation, is vital to developing new treatments for the dyslipidemias associated with metabolic syndrome. Apolipoproteins are a key component of lipoproteins. Apolipoproteins are proteins that structure lipoproteins and regulate lipid metabolism through control of cellular lipid exchange. Constraints of cell culture and mouse models mean that there is a need for a complementary model that can replicate the complex in vivo milieu that regulates apolipoprotein and lipoprotein biology. Here, we further establish the utility of the genetically tractable and optically clear larval zebrafish as a model of apolipoprotein biology. Gene ancestry analyses were implemented to determine the closest human orthologs of the zebrafish apolipoprotein A-I (apoA-I, apoB, apoE and apoA-IV genes and therefore ensure that they have been correctly named. Their expression patterns throughout development were also analyzed, by whole-mount mRNA in situ hybridization (ISH. The ISH results emphasized the importance of apolipoproteins in transporting yolk and dietary lipids: mRNA expression of all apolipoproteins was observed in the yolk syncytial layer, and intestinal and liver expression was observed from 4–6 days post-fertilization (dpf. Furthermore, real-time PCR confirmed that transcription of three of the four zebrafish apoA-IV genes was increased 4 hours after the onset of a 1-hour high-fat feed. Therefore, we tested the hypothesis that zebrafish ApoA-IV performs a conserved role to that in rat in the regulation of food intake by transiently overexpressing ApoA-IVb.1 in transgenic larvae and quantifying ingestion of co-fed fluorescently labeled fatty acid during a high-fat meal as an indicator of food intake. Indeed, ApoA-IVb.1 overexpression decreased food intake by approximately one-third. This study comprehensively describes the expression and function of eleven zebrafish

  4. Antipsychotic-like effect of GLP-1 agonist liraglutide but not DPP-IV inhibitor sitagliptin in mouse model for psychosis.

    Science.gov (United States)

    Dixit, Tejashree S; Sharma, Ajaykumar N; Lucot, James B; Elased, Khalid M

    2013-04-10

    Recent studies indicate a high comorbidity between type-2 diabetes mellitus (T2DM) and neurological disorders. Many are associated with abnormalities in dopamine neurotransmission such as schizophrenia. Because most of the antipsychotic drugs aggravate pre-existing insulin resistance in type-2 diabetics, there is a need to search for alternative antipsychotics. Glucagon like peptide-1 (GLP-1) is a gut hormone primarily involved in glucose homeostasis. GLP-1 agonist (liraglutide) and dipeptidyl peptidase-IV (DPP-IV) inhibitor (sitagliptin) are the US-FDA approved medications for the management of T2DM. However, little is known about their role in dopamine mediated neurological disorders like schizophrenia. To address this, we used apomorphine-induced cage climbing behavior as a murine model for psychosis and examined for potential antipsychotic-like effect of liraglutide and sitagliptin. While acute liraglutide treatment (50 μg/kg; i.p.) significantly attenuated apomorphine (3 mg/kg, s.c.) induced cage climbing, sitagliptin (50mg/kg; i.p.) failed to elicit such effect. This is the first preclinical evidence for antipsychotic-like effect of GLP-1 receptor agonist. These results open an opportunity to explore GLP-1 analogs for their potential to modulate spectrum of dopamine-mediated neurological disorders.

  5. Type-IV pili spectroscopic markers: applications in the quantification of piliation levels in Moraxella bovis cells by a FT-IR ANN-based model.

    Science.gov (United States)

    Bosch, Alejandra; Prieto, Claudia; Serra, Diego Omar; Martina, Pablo; Stämmbler, Maren; Naumann, Dieter; Schmitt, Jürgen; Yantorno, Osvaldo

    2010-08-01

    Type-IV pili are cell surface organelles found in a wide variety of Gram-negative bacteria. They have traditionally been detected by electron microscopy and ELISA techniques. However, these methodologies are not appropriate for the rapid discrimination and quantification of piliated and nonpiliated cells in industrial or field conditions. Here, the analysis of FT-IR spectra of piliated, nonpiliated and sheared Moraxella bovis cells, together with purified pili suspensions spectra, allowed the identification of 3 IR regions associated to spectroscopic markers of Type-IV pili: 1750-1600, 1450-1350 and 1280-950 cm(-1). Such IR-specific markers were found for piliated cells grown in different culture systems (liquid or solid media), independently of the strain or pili serotype. They were also sensitive to pili expression levels. Therefore, on the bases of these specific spectral features, an FT-IR ANN-based model was developed to classify piliation levels in 5 distinct groups. An overall classification rate of almost 90% demonstrates the strong potential of the ANN system developed to monitor M. bovis cultures in vaccine production.

  6. Secondary flow structures in the presence of Type-IV stent fractures through a bent tube model for curved arteries: Effect of circulation thresholding

    Science.gov (United States)

    Hussain, Shadman; Bulusu, Kartik V.; Plesniak, Michael W.

    2013-11-01

    A common treatment for atherosclerosis is the opening of narrowed arteries resulting from obstructive lesions by angioplasty and stent implantation to restore unrestricted blood flow. ``Type-IV'' stent fractures involve complete transverse, linear fracture of stent struts, along with displacement of the stent fragments. Experimental data pertaining to secondary flows in the presence of stents that underwent ``Type-IV'' fractures in a bent artery model under physiological inflow conditions were obtained through a two-component, two-dimensional (2C-2D) PIV technique. Concomitant stent-induced flow perturbations result in secondary flow structures with complex, multi-scale morphologies and varying size-strength characteristics. Ultimately, these flow structures may have a role to play in restenosis and progression of atherosclerotic plaque. Vortex circulation thresholds were established with the goal of resolving and tracking iso-circulation secondary flow vortical structures and their morphological changes. This allowed for a parametric evaluation and quantitative representation of secondary flow structures undergoing deformation and spatial reorganization. Supported by NSF Grant No. CBET- 0828903 and GW Center for Biomimetics and Bioinspired Engineering.

  7. IMPLEMETATION OF MODEL SAVI (SOMATIC, AUDIOTORY, VISUALIZATION, INTELLECTUAL TO INCREASE CRITICAL THINKING ABILITY IN CLASS IV OF SOCIAL SCIENCE LEARNING ON SOCIAL ISSUES IN THE LOCAL ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    Dadang Iskandar

    2016-03-01

    Full Text Available This research is motivated by the lack of critical thinking skills of fourth grade students of SDN Tanjung III, Subang district. On the basis of the need for repairs done either by applying the model of SAVI (Somatic, Auditory, Visualization, Intellectual. So the purpose of this study was to determine the increase critical thinking skills of students in Social Science before and after applying the model SAVI, the performance of teachers in applying the model SAVI, activities and students' response to the model SAVI. The method used in this research is the CAR (Classroom Action Research. Subject of research that fourth grade students of SDN Tanjung III by the number of students as many as 23 people. The instrument used was LKS (Student Worksheet, observation sheet of students and teachers as well as student questionnaire responses. From these results, it can be concluded that by applying the model in study SAVI social science with social problems in the local environment can enhance students' critical thinking skills. The result can be seen from the percentage of the overall level of mastery learning increased from 52.2% in the first cycle, 78.3% in the second cycle and 100% in the third cycle. The average grade class of students increased from 44.3 prasiklus of data with less criteria, up to the third cycle, which reached 91.3 with the criteria very well. With the improvement of students' critical thinking skills that are calculated based on the n-gain of 0.53 with the criteria of being in the first cycle, and 0.65 with the criteria of being on the second cycle, and 0.81 with the high criteria of the third cycle. The results of observations also showed that the ability of teachers and students' activity in applying the model of SAVI increased. Based on questionnaire responses, 100% of students showed interest in learning social science model with SAVI. Therefore, it is suggested that teachers use models SAVI  to enhance the critical thinking

  8. A comparison of the Graded Response and Partial Credit models with a scale of Usefulness of Mathematics

    Directory of Open Access Journals (Sweden)

    Abal, Facundo Juan Pablo

    2014-12-01

    Full Text Available The Graded Response Model (GRM and the Partial Credit Model (PCM of Item Response Theory (IRT were applied in the item analysis of a scale that evaluates psychology students's beliefs about the usefulness of mathematics. The scale comprises 8 items in polytomous response format (6-point Likert-type. The sample was made up by 1875 students of the Psychology school of the University of Buenos Aires. All analyses based on IRT were performed by operating the MULTILOG software. The parameters estimation was carried out trough Marginal Maximum Likelihood procedures. Previously, the unidimensionality assumption required by the models was confirmed. The GRM showed better fit indexes than PCM and higher Test Information Function. The findings provide validity evidences based on the internal structure of scale.

  9. Modeling high-grade serous carcinoma: how converging insights into pathogenesis and genetics are driving better experimental platforms

    Directory of Open Access Journals (Sweden)

    Paul Michael Jones

    2013-08-01

    Full Text Available Recent developments in the study of epithelial ovarian cancer have called into question the traditional views regarding the site of tumor initiation. Histopathologic studies and genomic analyses suggest that extra-ovarian sites, like the fallopian tube, may harbor the coveted cell of origin and could therefore contribute significantly to the development of high-grade serous ovarian carcinoma (HG-SOC. Our ability to validate these emerging genomic and pathologic observations and characterize the early transformation events of HG-SOC hinges on the development of novel model systems. Currently, there are only a handful of new model systems that are addressing these concerns. This review will chronicle the convergent evolution of these ovarian cancer model systems in the context of the changing pathologic and genomic understanding of HG-SOC.

  10. Grading the probabilities of credit default risk for Malaysian listed companies by using the KMV-Merton model

    Science.gov (United States)

    Anuwar, Muhammad Hafidz; Jaffar, Maheran Mohd

    2017-08-01

    This paper provides an overview for the assessment of credit risk specific to the banks. In finance, risk is a term to reflect the potential of financial loss. The risk of default on loan may increase when a company does not make a payment on that loan when the time comes. Hence, this framework analyses the KMV-Merton model to estimate the probabilities of default for Malaysian listed companies. In this way, banks can verify the ability of companies to meet their loan commitments in order to overcome bad investments and financial losses. This model has been applied to all Malaysian listed companies in Bursa Malaysia for estimating the credit default probabilities of companies and compare with the rating given by the rating agency, which is RAM Holdings Berhad to conform to reality. Then, the significance of this study is a credit risk grade is proposed by using the KMV-Merton model for the Malaysian listed companies.

  11. Research on the Model of Emotional Graded BDI Agents%情感等级BDI主体模型研究

    Institute of Scientific and Technical Information of China (English)

    张晓君; 周昌乐

    2013-01-01

      信念、愿望和意图(BDI)模型是近年来影响最为深远的主体技术之一。文中把命题动态逻辑和无穷值的Łukasiewicz逻辑进行融合后对情感等级BDI主体模型进行了形式化。为通过信念度、愿望度、意图度、害怕度、焦虑度和自信度对不确定性行为进行表示和推理,把相应的公理添加到Łukasiewicz逻辑中。文中的情感等级BDI主体模型的行为是通过添加具体条件的每种背景的不同测度来决定,清晰地表示主体的心理状态和情感状态的不确定性。文中对情感等级BDI模型进行公理化,并说明它们对主体行为的影响。此模型可较轻易地向包括其它心理状态和情感状态的主体进行推广。文中在给出情感等级BDI模型的语言、语义及公理和演绎规则后,证明此逻辑系统的可靠性和完全性。随后给出情感等级BDI主体模型的不同背景之间的相互关系,并对该主体的买房行动进行实例分析。本研究立足于不确定性的表示和推理,旨在为分布式人工智能提供形式支持。%In recent years, the Belief-Desire-Intention model is one of the most influential theories with respect to agent technology. Propositional dynamic logic and the infinite-valued Łukasiewicz logic are blended to formulize the emotional graded BDI model. In order to represent the uncertainty behaviors by belief, desire, intention, fear, anxiety and self-confidence degree, the corresponding axioms are added to theŁukasiewicz logic. The proposed emotional graded BDI agent model explicitly represents the uncertainty of mental attitudes and emotional states. The behavior of emotional graded BDI agent is determined by the different measure of each context which is added by concrete conditions. The model of beliefs, desires, intentions, fear, anxiety and self-confidence are axiomatized, and how they influence the behavior of agent is shown. This model is general enough

  12. A Model of Solar Radiation and Joule Heating in Flow of Third Grade Nanofluid

    Science.gov (United States)

    Hussain, Tariq; Hayat, Tasawar; Shehzad, Sabir Ali; Alsaedi, Ahmed; Chen, Bin

    2015-03-01

    The flow problem resulting from the stretching of a surface with convective conditions in a magnetohydrodynamic nanofluid with solar radiation is examined. Both heat and nanoparticle mass transfer convective conditions are employed. An incompressible third grade fluid which exhibits shear thinning and shear thickening characteristics is used as a base fluid. Concept of convective nanoparticle mass condition is introduced. Effects of Brownian motion and thermophoresis on magnetohydrodynamic flow of nanofluid are accounted in the presence of thermal radiation. Energy equation incorporates the features of Joule heating. The impact of physical parameters on the temperature and nanoparticle concentration has been pointed out. Numerical values of skin-friction coefficient are presented and analysed. It is hoped that this present investigation serves as a stimulus for the next generation of solar film collectors, heat exchangers technology, material processing, geothermal energy storage, and all those processes which are highly affected by the heat enhancement concept.

  13. Comparison of modeling of the rotating tapered axially functionally graded Timoshenko and Euler-Bernoulli microbeams

    Science.gov (United States)

    Shafiei, Navvab; Kazemi, Mohammad; Ghadiri, Majid

    2016-09-01

    The target of this paper is to present an exhaustive study on the small scale effect on vibrational behavior of a rotary tapered axially functionally graded (AFG) microbeam on the basis of Timoshenko and Euler-Bernoulli beam and modified couple stress theories. The variation of the material properties and cross section along the longitudinal direction of the microbeam are taken into consideration as a linear function. Hamilton's principle is used to derive the equations for cantilever and propped cantilever boundary conditions and the generalized differential quadrature method (GDQM) is employed to solve the equations. By parametric study, the effects of small-scale parameter, rates of cross section change of the microbeam and angular velocity on the fundamental and second frequencies of the microbeam are studied. Also, comparison between the frequencies of Timoshenko and Euler-Bernoulli microbeams are presented. The results can be used in many applications such as micro-robots and biomedical microsystems.

  14. Hydrology in a Mediterranean mountain environment, the Vallcebre Research basins (North Eastern Spain). IV. Testing hydrological and erosion models

    Energy Technology Data Exchange (ETDEWEB)

    Gallart, F.; Latron, J.; Llorens, P.; Martinez-Carreras, N.

    2009-07-01

    Three modelling exercises were carried out in the Vallcebre research basins in order to both improve the understanding of the hydrological processes and test the adequate of some models in such Mediterranean mountain conditions. These exercises consisted of i) the analysis of the hydrological role of the agricultural terraces using the TOPMODEL topographic index, ii) the parametrisation of TOPMODEL using internal basin information, and iii) a test of the erosion model KINEROS2 for simulating badlands erosion. (Author) 13 refs.

  15. Graded core/shell semiconductor nanorods and nanorod barcodes

    Science.gov (United States)

    Alivisatos, A. Paul; Scher, Erik C.; Manna, Liberato

    2009-05-19

    Disclosed herein is a graded core/shell semiconductor nanorod having at least a first segment of a core of a Group II-VI, Group III-V or a Group IV semiconductor, a graded shell overlying the core, wherein the graded shell comprises at least two monolayers, wherein the at least two monolayers each independently comprise a Group II-VI, Group III-V or a Group IV semiconductor.

  16. The Reciprocal Internal/External Frame of Reference Model Using Grades and Test Scores

    Science.gov (United States)

    Möller, Jens; Zimmermann, Friederike; Köller, Olaf

    2014-01-01

    Background: The reciprocal I/E model (RI/EM) combines the internal/external frame of reference model (I/EM) with the reciprocal effects model (REM). The RI/EM extends the I/EM longitudinally and the REM across domains. The model predicts that, within domains, mathematics and verbal achievement (VACH) and academic self-concept have positive effects…

  17. Boundary Conditions in 2D Numerical and 3D Exact Models for Cylindrical Bending Analysis of Functionally Graded Structures

    Directory of Open Access Journals (Sweden)

    F. Tornabene

    2016-01-01

    Full Text Available The cylindrical bending condition for structural models is very common in the literature because it allows an incisive and simple verification of the proposed plate and shell models. In the present paper, 2D numerical approaches (the Generalized Differential Quadrature (GDQ and the finite element (FE methods are compared with an exact 3D shell solution in the case of free vibrations of functionally graded material (FGM plates and shells. The first 18 vibration modes carried out through the 3D exact model are compared with the frequencies obtained via the 2D numerical models. All the 18 frequencies obtained via the 3D exact model are computed when the structures have simply supported boundary conditions for all the edges. If the same boundary conditions are used in the 2D numerical models, some modes are missed. Some of these missed modes can be obtained modifying the boundary conditions imposing free edges through the direction perpendicular to the direction of cylindrical bending. However, some modes cannot be calculated via the 2D numerical models even when the boundary conditions are modified because the cylindrical bending requirements cannot be imposed for numerical solutions in the curvilinear edges by definition. These features are investigated in the present paper for different geometries (plates, cylinders, and cylindrical shells, types of FGM law, lamination sequences, and thickness ratios.

  18. The Development of Learning Model Based on Problem Solving to Construct High-Order Thinking Skill on the Learning Mathematics of 11th Grade in SMA/MA

    Science.gov (United States)

    Syahputra, Edi; Surya, Edy

    2017-01-01

    This paper is a summary study of team Postgraduate on 11th grade. The objective of this study is to develop a learning model based on problem solving which can construct high-order thinking on the learning mathematics in SMA/MA. The subject of dissemination consists of Students of 11th grade in SMA/MA in 3 kabupaten/kota in North Sumatera, namely:…

  19. The effect of a multicomponent literacy instruction model on literacy growth for kindergartners and first-grade students in Chile.

    Science.gov (United States)

    Pallante, Daniel H; Kim, Young-Suk

    2013-01-01

    In the present study we examined the impact of a comprehensive literacy instruction model called Collaborative Language and Literacy Instruction Project (CLLIP) on language and literacy achievement over the course of a year by Spanish-speaking children in Chile. Participants included kindergartners (N = 312) from high and low socioeconomic backgrounds and first-grade students (N = 305) from high SES families. The CLLIP model targeted phonological awareness, alphabetics and phonics, fluency, vocabulary, reading comprehension and writing, and included coaching and sustained follow-up as key elements for teacher professional development. The results showed promise for the CLLIP model in the Chilean context. Kindergartners in CLLIP classrooms had faster growth rates in letter naming, word reading, vocabulary, and phonemic segmentation fluency than those in control classrooms, and had higher scores at the end of the year in phonemic segmentation fluency, letter naming, and word reading. In addition, kindergartners from high SES families had faster growth rates than kindergartners from low SES families in letter naming and word reading. Effect sizes ranged from small (d = .18 in word reading) to fairly large (d = .70 in letter-naming fluency). First-grade students in CLLIP classrooms had faster growth rates than students in control classrooms in vocabulary, nonword reading fluency, word reading, and reading comprehension. Effect sizes were small in vocabulary, nonword reading fluency, and reading comprehension (.23 ≤ d ≤ .28) and medium in word reading (d = .50). These results suggest that the present multicomponent literacy instructional model had a positive impact on Chilean children's literacy acquisition.

  20. Industrial Sector Technology Use Model (ISTUM): industrial energy use in the United States, 1974-2000. Volume 1: primary model documentation, Book 2, Chapters IV, V, VI, and VII

    Energy Technology Data Exchange (ETDEWEB)

    Bohn, R.E.; Herod, J.S.

    1978-06-19

    The Industrial Sector Technology Use Model provides a single framework for integrating all of the information and analysis into a set of predictions of industrial energy use. Given this volume of information which must be considered, this requires a set of computerized engineering-economic models. The design of these models is the subject of Chapter IV. The environmental factors in ISTUM are developed and presented in Chapter V. Chapter VI discusses the work accomplished by DATA Resources, Inc. in support of the ISTUM. A glossary, briefly defining special terms used in the ISTUM documentation, is given in Chapter VII. (MCW)

  1. Synthetic photometry for carbon-rich giants. IV. An extensive grid of dynamic atmosphere and wind models

    Science.gov (United States)

    Eriksson, K.; Nowotny, W.; Höfner, S.; Aringer, B.; Wachter, A.

    2014-06-01

    Context. The evolution and spectral properties of stars on the asymptotic giant branch (AGB) are significantly affected by mass loss through dusty stellar winds. Dynamic atmosphere and wind models are an essential tool for studying these evolved stars, both individually and as members of stellar populations, to understand their contribution to the integrated light and chemical evolution of galaxies. Aims: This paper is part of a series with the purpose of testing state-of-the-art atmosphere and wind models of C-type AGB stars against observations, and making them available to the community for use in various theoretical and observational studies. Methods: We have computed low-resolution spectra and photometry (in the wavelength range 0.35-25 μm) for a grid of 540 dynamic models with stellar parameters typical of solar-metallicity C-rich AGB stars and with a range of pulsation amplitudes. The models cover the dynamic atmosphere and dusty outflow (if present), assuming spherical symmetry, and taking opacities of gas-phase species and dust grains consistently into account. To characterize the time-dependent dynamic and photometric behaviour of the models in a concise way we defined a number of classes for models with and without winds. Results: Comparisons with observed data in general show a quite satisfactory agreement for example regarding mass-loss rates vs. (J - K) colours or K magnitudes vs. (J - K) colours. Some exceptions from the good overall agreement, however, are found and attributed to the range of input parameters (e.g. relatively high carbon excesses) or intrinsic model assumptions (e.g. small particle limit for grain opacities). Conclusions: While current results indicate that some changes in model assumptions and parameter ranges should be made in the future to bring certain synthetic observables into better agreement with observations, it seems unlikely that these pending improvements will significantly affect the mass-loss rates of the models

  2. Application of a level IV fugacity model to simulate the long-term fate of hexachlorocyclohexane isomers in the lower reach of Yellow River basin, China.

    Science.gov (United States)

    Ao, Jiangting; Chen, Jingwen; Tian, Fulin; Cai, Xiyun

    2009-01-01

    A level IV multimedia fugacity model was established to simulate the fate and transfer of hexachlorocyclohexane (HCH) isomers in the lower reach of the Yellow River basin, China, during 1952-2010. The predicted concentrations of HCHs are in good agreement with the observed ones, as indicated by the residual errors being generally lower than 0.5 logarithmic units. The effects of extensive agricultural application and subsequent prohibition of HCHs are reflected by the temporal variation of HCHs predicted by the model. It is predicted that only 1.8 tons of HCHs will be left in 2010, less than 0.06% of the highest contents (in 1983) in the study area, and about 99% of HCHs remain in soil. The proportions of HCH isomers in the environment also changed with time due to their different physicochemical properties. Although beta-HCH is not the main component of the technical HCHs, it has become the most abundant isomer in the environment because of its persistence. The dominant transfer processes between the adjacent compartments were deposition from air to soil, air diffusion through the air-water interface and runoff from soil to water. Sensitivity analysis showed that degradation rate in soil, parameters related to major sources, and thickness of soils had the strongest influence on the model result. Results of Monte Carlo simulation indicated the overall uncertainty of model predictions, and the coefficients of variation of the estimated concentrations of HCHs in all the compartments ranged from 0.5 to 5.8.

  3. Simulating Radiotherapy Effect in High-Grade Glioma by Using Diffusive Modeling and Brain Atlases

    Directory of Open Access Journals (Sweden)

    Alexandros Roniotis

    2012-01-01

    Full Text Available Applying diffusive models for simulating the spatiotemporal change of concentration of tumour cells is a modern application of predictive oncology. Diffusive models are used for modelling glioblastoma, the most aggressive type of glioma. This paper presents the results of applying a linear quadratic model for simulating the effects of radiotherapy on an advanced diffusive glioma model. This diffusive model takes into consideration the heterogeneous velocity of glioma in gray and white matter and the anisotropic migration of tumor cells, which is facilitated along white fibers. This work uses normal brain atlases for extracting the proportions of white and gray matter and the diffusion tensors used for anisotropy. The paper also presents the results of applying this glioma model on real clinical datasets.

  4. Schwinger-Dyson operator of Yang-Mills matrix models with ghosts and derivations of the graded shuffle algebra

    Energy Technology Data Exchange (ETDEWEB)

    Krishnaswami, Govind S [Institute for Theoretical Physics and Spinoza Institute, Utrecht University, Postbus 80.195, 3508 TD, Utrecht (Netherlands)], E-mail: govind.krishnaswami@durham.ac.uk

    2008-04-11

    We consider large-N multi-matrix models whose action closely mimics that of Yang-Mills theory, including gauge-fixing and ghost terms. We show that the factorized Schwinger-Dyson loop equations, expressed in terms of the generating series of gluon and ghost correlations G({xi}), are quadratic equations S{sup i}G=G{xi}{sup i}G in concatenation of correlations. The Schwinger-Dyson operator S{sup i} is built from the left annihilation operator, which does not satisfy the Leibnitz rule with respect to concatenation. So the loop equations are not differential equations. We show that left annihilation is a derivation of the graded shuffle product of gluon and ghost correlations. The shuffle product is the point-wise product of Wilson loops, expressed in terms of correlations. So in the limit where concatenation is approximated by shuffle products, the loop equations become differential equations. Remarkably, the Schwinger-Dyson operator as a whole is also a derivation of the graded shuffle product. This allows us to turn the loop equations into linear equations for the shuffle reciprocal, which might serve as a starting point for an approximation scheme.

  5. A phase-field approach to model multi-axial and microstructure dependent fracture in nuclear grade graphite

    Science.gov (United States)

    Chakraborty, Pritam; Sabharwall, Piyush; Carroll, Mark C.

    2016-07-01

    The fracture behavior of nuclear grade graphites is strongly influenced by underlying microstructural features such as the character of filler particles, and the distribution of pores and voids. These microstructural features influence the crack nucleation and propagation behavior, resulting in quasi-brittle fracture with a tortuous crack path and significant scatter in measured bulk strength. This study uses a phase-field method to model the microstructural and multi-axial fracture in H-451, a historic variant of nuclear graphite that provides the basis for an idealized study on a legacy grade. The representative volume elements are constructed from randomly located pores with random size obtained from experimentally determined log-normal distribution. The representative volume elements are then subjected to simulated multi-axial loading, and a reasonable agreement of the resulting fracture stress with experiments is obtained. Quasi-brittle stress-strain evolution with a tortuous crack path is also observed from the simulations and is consistent with experimental results.

  6. Analytical modeling of dynamic behavior of piezo-thermo-electrically affected sigmoid and power-law graded nanoscale beams

    Science.gov (United States)

    Ebrahimi, Farzad; Salari, Erfan

    2016-09-01

    In the present study, thermo-electro-mechanical vibration characteristics of both sigmoid and power-law functionally graded piezoelectric (FGP) nanobeams subjected to in-plane thermal loads and applied electric voltage are carried out by presenting a Navier-type solution for the first time. Three kinds of thermal loading, namely uniform, linear and nonlinear temperature rises through the thickness direction are considered. Thermo-electro-mechanical properties of FGP nanobeam are supposed to vary smoothly and continuously throughout the thickness according to power-law and sigmoid distribution. Eringen's nonlocal elasticity theory is exploited to describe the size dependency of nanobeam. Using Hamilton's principle, the nonlocal equations of motion together with corresponding boundary conditions are obtained for the free vibration analysis of graded piezoelectric nanobeams including size effect and they are solved applying analytical solution. According to the numerical results, it is revealed that the proposed modeling can provide accurate frequency results of the FG nanobeams as compared some cases in the literature. In following a parametric study is accompanied to examine the effects of the several parameters such as various temperature distributions, external electric voltage, different material compositions, nonlocal parameter and mode number on the natural frequencies of the size-dependent FGP nanobeams in detail. It is found that the small scale effect and thermo-electrical loading have a significant effect on natural frequencies of FGP nanobeams. The results should be relevant to the design and application of the piezoelectric nanodevices.

  7. On a minimal model for hemodynamics and metabolism of lactate: application to low grade glioma and therapeutic strategies.

    Science.gov (United States)

    Lahutte-Auboin, Marion; Guillevin, Rémy; Françoise, Jean-Pierre; Vallée, Jean-Noël; Costalat, Robert

    2013-03-01

    WHO II low grade glioma evolves inevitably to anaplastic transformation. Magnetic resonance imaging is a good non-invasive way to watch it, by hemodynamic and metabolic modifications, thanks to multinuclear spectroscopy (1)H/(31)P. In this work we study a multi-scale minimal model of hemodynamics and metabolism applied to the study of gliomas. This mathematical analysis leads us to a fast-slow system. The control of the position of the stationary point brings to the concept of domain of viability. Starting from this system, the equations bring to light the parameters that push glioma cells out of their domain of viability. Four fundamental factors are highlighted. The first two are cerebral blood flow and the rate of lactate transport through monocarboxylate transporters, which must be reduced in order to push glioma out of its domain of viability. Another factor is the intra arterial lactate, which must be increased. The last factor is pH, indeed a decrease of intra cellular pH could interfere with glioma growth. These reflections suggest that these four parameters could lead to new therapeutic strategies for the management of low grade gliomas.

  8. The K20 survey. IV. The redshift distribution of Ks<20 galaxies a test of galaxy formation models

    CERN Document Server

    Cimatti, A; Mignoli, M; Daddi, E; Menci, N; Poli, F; Fontana, A; Renzini, A; Zamorani, G; Broadhurst, T J; Cristiani, S; D'Odorico, S; Giallongo, E; Gilmozzi, R

    2002-01-01

    We present the redshift distribution of a complete sample of 480 galaxies with Ks1 and z>1.5 respectively. A ``blind'' comparison is made with the predictions of a set of the most recent LambdaCDM hierarchical merging and pure luminosity evolution (PLE) models. The hierarchical merging models overpredict and underpredict the number of galaxies at low-z and high-z respectively, whereas the PLE models match the median redshift and the low-z distribution, still being able to follow the high-z tail of N(z). We briefly discuss the implications of this comparison and the possible origins of the observed discrepancies. We make the redshift distribution publicly available.

  9. Project on Elite Athlete Commitment (PEAK): IV. identification of new candidate commitment sources in the sport commitment model.

    Science.gov (United States)

    Scanlan, Tara K; Russell, David G; Scanlan, Larry A; Klunchoo, Tatiana J; Chow, Graig M

    2013-10-01

    Following a thorough review of the current updated Sport Commitment Model, new candidate commitment sources for possible future inclusion in the model are presented. They were derived from data obtained using the Scanlan Collaborative Interview Method. Three elite New Zealand teams participated: amateur All Black rugby players, amateur Silver Fern netball players, and professional All Black rugby players. An inductive content analysis of these players' open-ended descriptions of their sources of commitment identified four unique new candidate commitment sources: Desire to Excel, Team Tradition, Elite Team Membership, and Worthy of Team Membership. A detailed definition of each candidate source is included along with example quotes from participants. Using a mixed-methods approach, these candidate sources provide a basis for future investigations to test their viability and generalizability for possible expansion of the Sport Commitment Model.

  10. The developmental impact of two first grade preventive interventions on aggressive/disruptive behavior in childhood and adolescence: an application of latent transition growth mixture modeling.

    Science.gov (United States)

    Petras, Hanno; Masyn, Katherine; Ialongo, Nick

    2011-09-01

    We examine the impact of two universal preventive interventions in first grade on the growth of aggressive/disruptive behavior in grades 1-3 and 6-12 through the application of a latent transition growth mixture model (LT-GMM). Both the classroom-centered and family-centered interventions were designed to reduce the risk for later conduct problems by enhancing the child behavior management practices of teachers and parents, respectively. We first modeled growth trajectories in each of the two time periods with separate GMMs. We then associated latent trajectory classes of aggressive/disruptive behavior across the two time periods using a transition model for the corresponding latent class variables. Subsequently, we tested whether the interventions had direct effects on trajectory class membership in grades 1-3 and 6-12. For males, both the classroom-centered and family-centered interventions had significant direct effects on trajectory class membership in grades 6-12, whereas only the classroom-centered intervention had a significant effect on class membership in grades 1-3. Significant direct effects for females were confined to grades 1-3 for the classroom-centered intervention. Further analyses revealed that both the classroom-centered and family-centered intervention males were significantly more likely than control males to transition from the high trajectory class in grades 1-3 to a low class in grades 6-12. Effects for females in classroom-centered interventions went in the hypothesized direction but did not reach significance. © Society for Prevention Research 2011

  11. Extending the Diffuse Layer Model of Surface Acidity Constant Behavior: IV. Diffuse Layer Charge/Potential Relationships

    Science.gov (United States)

    Most current electrostatic surface complexation models describing ionic binding at the particle/water interface rely on the use of Poisson - Boltzmann (PB) theory for relating diffuse layer charge densities to diffuse layer electrostatic potentials. PB theory is known to contain ...

  12. Offshore Code Comparison Collaboration within IEA Wind Task 23: Phase IV Results Regarding Floating Wind Turbine Modeling; Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Jonkman, J.; Larsen, T.; Hansen, A.; Nygaard, T.; Maus, K.; Karimirad, M.; Gao, Z.; Moan, T.; Fylling, I.

    2010-04-01

    Offshore wind turbines are designed and analyzed using comprehensive simulation codes that account for the coupled dynamics of the wind inflow, aerodynamics, elasticity, and controls of the turbine, along with the incident waves, sea current, hydrodynamics, and foundation dynamics of the support structure. This paper describes the latest findings of the code-to-code verification activities of the Offshore Code Comparison Collaboration, which operates under Subtask 2 of the International Energy Agency Wind Task 23. In the latest phase of the project, participants used an assortment of codes to model the coupled dynamic response of a 5-MW wind turbine installed on a floating spar buoy in 320 m of water. Code predictions were compared from load-case simulations selected to test different model features. The comparisons have resulted in a greater understanding of offshore floating wind turbine dynamics and modeling techniques, and better knowledge of the validity of various approximations. The lessons learned from this exercise have improved the participants' codes, thus improving the standard of offshore wind turbine modeling.

  13. Modelling the Pan-Spectral Energy Distribution of Starburst Galaxies: IV The Controlling Parameters of the Starburst SED

    CERN Document Server

    Groves, B; Sutherland, R; Kewley, L; Fischera, J; Leitherer, C; Brandl, B; van Breugal, W

    2007-01-01

    We combine the the stellar spectral synthesis code Starburst99, the nebular modelling code MAPPINGSIII, and a 1-D dynamical evolution model of HII regions around massive clusters of young stars to generate improved models of the spectral energy distribution (SED) of starburst galaxies. We introduce a compactness parameter, C, which characterizes the specific intensity of the radiation field at ionization fronts in HII regions, and which controls the shape of the far-IR dust re-emission, often referred to loosely as the dust ``temperature''. We also investigate the effect of metallicity on the overall SED and in particular, on the strength of the PAH features. We provide templates for the mean emission produced by the young compact HII regions, the older (10 - 100 Myr) stars and for the wavelength-dependent attenuation produced by a foreground screen of the dust used in our model. We demonstrate that these components may be combined to produce a excellent fit to the observed SEDs of star formation dominated ga...

  14. Carbon and nitrogen cycling on intertidal mudflats of a temperate Australian estuary. IV. Inverse model analysis and synthesis

    NARCIS (Netherlands)

    Cook, P.L.M.; Oevelen, D. van; Soetaert, K.; Middelburg, J.J.

    2009-01-01

    Microphytobenthos (MPB) are recognised as exerting an important controlling influence over C and N flows in euphotic sediments; however, the coupling between these flows remains poorly studied. We undertook an inverse model analysis of C and N fluxes through the microbial compartment on intertidal

  15. Synthetic photometry for carbon-rich giants. IV. An extensive grid of dynamic atmosphere and wind models

    CERN Document Server

    Eriksson, Kjell; Höfner, Susanne; Aringer, Bernhard; Wachter, Astrid

    2014-01-01

    The evolution and spectral properties of stars on the AGB are significantly affected by mass loss through dusty stellar winds. Dynamic atmosphere and wind models are an essential tool for studying these evolved stars, both individually and as members of stellar populations, to understand their contribution to the integrated light and chemical evolution of galaxies. This paper is part of a series testing state-of-the-art atmosphere and wind models of carbon stars against observations, and making them available for use in various theoretical and observational studies. We have computed low-resolution spectra and photometry (in the wavelength range 0.35-25 mu) for a grid of 540 dynamic models with stellar parameters typical of solar-metallicity C-rich AGB stars and with a range of pulsation amplitudes. The models cover the dynamic atmosphere and dusty outflow (if present), assuming spherical symmetry, and taking opacities of gas-phase species and dust grains consistently into account. To characterize the time-dep...

  16. Extending MAM5 Meta-Model and JaCalIV E Framework to Integrate Smart Devices from Real Environments.

    Directory of Open Access Journals (Sweden)

    J A Rincon

    Full Text Available This paper presents the extension of a meta-model (MAM5 and a framework based on the model (JaCalIVE for developing intelligent virtual environments. The goal of this extension is to develop augmented mirror worlds that represent a real and virtual world coupled, so that the virtual world not only reflects the real one, but also complements it. A new component called a smart resource artifact, that enables modelling and developing devices to access the real physical world, and a human in the loop agent to place a human in the system have been included in the meta-model and framework. The proposed extension of MAM5 has been tested by simulating a light control system where agents can access both virtual and real sensor/actuators through the smart resources developed. The results show that the use of real environment interactive elements (smart resource artifacts in agent-based simulations allows to minimize the error between simulated and real system.

  17. A unified gas-kinetic scheme for continuum and rarefied flows IV: Full Boltzmann and model equations

    Science.gov (United States)

    Liu, Chang; Xu, Kun; Sun, Quanhua; Cai, Qingdong

    2016-06-01

    Fluid dynamic equations are valid in their respective modeling scales, such as the particle mean free path scale of the Boltzmann equation and the hydrodynamic scale of the Navier-Stokes (NS) equations. With a variation of the modeling scales, theoretically there should have a continuous spectrum of fluid dynamic equations. Even though the Boltzmann equation is claimed to be valid in all scales, many Boltzmann solvers, including direct simulation Monte Carlo method, require the cell resolution to the order of particle mean free path scale. Therefore, they are still single scale methods. In order to study multiscale flow evolution efficiently, the dynamics in the computational fluid has to be changed with the scales. A direct modeling of flow physics with a changeable scale may become an appropriate approach. The unified gas-kinetic scheme (UGKS) is a direct modeling method in the mesh size scale, and its underlying flow physics depends on the resolution of the cell size relative to the particle mean free path. The cell size of UGKS is not limited by the particle mean free path. With the variation of the ratio between the numerical cell size and local particle mean free path, the UGKS recovers the flow dynamics from the particle transport and collision in the kinetic scale to the wave propagation in the hydrodynamic scale. The previous UGKS is mostly constructed from the evolution solution of kinetic model equations. Even though the UGKS is very accurate and effective in the low transition and continuum flow regimes with the time step being much larger than the particle mean free time, it still has space to develop more accurate flow solver in the region, where the time step is comparable with the local particle mean free time. In such a scale, there is dynamic difference from the full Boltzmann collision term and the model equations. This work is about the further development of the UGKS with the implementation of the full Boltzmann collision term in the region

  18. Combinatorial and model-theoretical principles related to regularity of ultrafilters and compactness of topological spaces. IV

    CERN Document Server

    Lipparini, Paolo

    2008-01-01

    We extend to singular cardinals the model-theoretical relation $\\lambda \\stackrel{\\kappa}{\\Rightarrow} \\mu$ introduced in P. Lipparini, The compactness spectrum of abstract logics, large cardinals and combinatorial principles, Boll. Unione Matematica Italiana ser. VII, {\\bf 4-B} 875--903 (1990). We extend some results obtained in Part II, finding equivalent conditions involving uniformity of ultrafilters and the existence of certain infinite matrices. Our present definition suggests a new compactness property for abstract logics.

  19. Exploring Third-Grade Student Model-Based Explanations about Plant Relationships within an Ecosystem

    Science.gov (United States)

    Zangori, Laura; Forbes, Cory T.

    2015-01-01

    Elementary students should have opportunities to develop scientific models to reason and build understanding about how and why plants depend on relationships within an ecosystem for growth and survival. However, scientific modeling practices are rarely included within elementary science learning environments and disciplinary content is often…

  20. Modelling of and Conjecturing on a Soccer Ball in a Korean Eighth Grade Mathematics Classroom

    Science.gov (United States)

    Lee, Kyeong-Hwa

    2011-01-01

    The purpose of this article was to describe the task design and implementation of cultural artefacts in a mathematics lesson based on the integration of modelling and conjecturing perspectives. The conceived process of integrating a soccer ball into mathematics lessons via modelling- and conjecturing-based instruction was first detailed. Next, the…

  1. A Teaching Model for Scaffolding 4th Grade Students' Scientific Explanation Writing

    Science.gov (United States)

    Yang, Hsiu-Ting; Wang, Kuo-Hua

    2014-01-01

    Improving students scientific explanations is one major goal of science education. Both writing activities and concept mapping are reported as effective strategies for enhancing student learning of science. The purpose of this study was to examine the effect of a teaching model, named the DCI model, which integrates a Descriptive explanation…

  2. Increasing Parental Involvement in the Primary Grades: The Magowan School Model.

    Science.gov (United States)

    Galen, Harlene

    Each school's version of a partnership with parents is unique, and no generic model exists. Designated in 1988 as one of 14 model schools in the New Jersey State Department of Education "Parents as Partners in Learning" project, the Mildred Magowan school in Edgewater Park has followed a systematic approach that has consistently led to…

  3. Development of Mathematical Model on Preparation of Functionally Graded Material by Co-sedimentation

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    From the process of sedimentation the mathematical relationshipsamong deposition volume and powder properties as well as sedimentation parameters were deduced. Based on the formula a mathematical model was set up and simulated through the computer. At last the validity of mathematical model was supported by the representative experiment on Ti-Mo system FGM prepared by co-sedimentation.

  4. Modeling Relationships among Learning, Attitude, Self-Perception, and Science Achievement for Grade 8 Saudi Students

    Science.gov (United States)

    Tighezza, M'Hamed

    2014-01-01

    The purpose of the present study was to examine the validity of modeling science achievement in terms of 3 social psychological variables (school connectedness, science attitude, and active learning) and 2 self-perception variables (self-confidence and science value). Two models were tested: full mediation and partial mediation. In the…

  5. Modelling of and Conjecturing on a Soccer Ball in a Korean Eighth Grade Mathematics Classroom

    Science.gov (United States)

    Lee, Kyeong-Hwa

    2011-01-01

    The purpose of this article was to describe the task design and implementation of cultural artefacts in a mathematics lesson based on the integration of modelling and conjecturing perspectives. The conceived process of integrating a soccer ball into mathematics lessons via modelling- and conjecturing-based instruction was first detailed. Next, the…

  6. A dynamic level IV multimedia environmental model: application to the fate of polychlorinated biphenyls in the United Kingdom over a 60-year period.

    Science.gov (United States)

    Sweetman, Andrew J; Cousins, Ian T; Seth, Rajesh; Jones, Kevin C; Mackay, Donald

    2002-05-01

    A dynamic or level IV multimedia model is described and illustrated by application to the fate of three polychlorinated biphenyl (PCB) congeners in the United Kingdom over a 60-year period from their introduction into commerce until the present. Models of this type are shown to be valuable for elucidating the time response of environmental systems to increasing, decreasing, or pulse inputs. The suggestion is made that in addition to the outputs of time-dependent concentrations (which can be compared with monitoring data for validation purposes), it is useful to examine masses, fugacities, and fugacity ratios between media? The relative importance of processes is best evaluated by compiling cumulative intermedia fluxes and quantities lost by reaction and advection and examining the corresponding process rate constants or their reciprocals, the characteristic times. The suggestion is made that uncertainty and sensitivity analyses are desirable, but it must be appreciated that relative sensitivities of input parameters may change during the simulation period, so a single sensitivity analysis conducted at one point in time can be misleading. The use of the model for forecasting future trends in concentration is illustrated. Given the uncertainties in emission and advective inflow rates, the simulation of PCB fate in the United Kingdom is regarded as showing time trends that are in satisfactory agreement with monitoring data.

  7. A Thermodynamic Model for Acetate, Lactate, and Oxalate Complexation with Am(III), Th(IV), Np(V), and U(VI) Valid to High Ionic Strength

    Energy Technology Data Exchange (ETDEWEB)

    Bynaum, R.V.; Free, S.J.; Moore, R.C.

    1999-01-15

    The organic ligands acetate, lactate, oxalate and EDTA have been identified as components of wastes targeted for disposal in the Waste Isolation Pilot Plant (WIPP) located in Southeastern New Mexico. The presence of these ligands is of concern because complexation of the actinides with the ligands may increase dissolved actinide concentrations and impact chemical retardation during transport. The current work considers the complexation of Am(III), Th (IV), Np(V), and U(W) with two of the organic ligands, acetate and lactate, in NaCl media from dilute through high concentration. A thermodynamic model for actinide complexation with the organic ligands has been developed based on the Pitzer activity coefficient formalism and the Harvie-Moller-Weare, Felmy-Weare database for describing brine evaporite systems. The model was parameterized using first apparent stability constant data from the literature. Because of complexation of other metal ions (Fe, Mg, Ni, Pb, etc.) present in the WIPP disposal room with the organic ligands, preliminary results from model calculations indicate the organic ligands do not significantly increase dissolved actinide concentrations.

  8. DA-1229, a dipeptidyl peptidase IV inhibitor, protects against renal injury by preventing podocyte damage in an animal model of progressive renal injury.

    Science.gov (United States)

    Eun Lee, Jee; Kim, Jung Eun; Lee, Mi Hwa; Song, Hye Kyoung; Ghee, Jung Yeon; Kang, Young Sun; Min, Hye Sook; Kim, Hyun Wook; Cha, Jin Joo; Han, Jee Young; Han, Sang Youb; Cha, Dae Ryong

    2016-05-01

    Although dipeptidyl peptidase IV (DPPIV) inhibitors are known to have renoprotective effects, the mechanism underlying these effects has remained elusive. Here we investigated the effects of DA-1229, a novel DPPIV inhibitor, in two animal models of renal injury including db/db mice and the adriamycin nephropathy rodent model of chronic renal disease characterized by podocyte injury. For both models, DA-1229 was administered at 300 mg/kg/day. DPPIV activity in the kidney was significantly higher in diabetic mice compared with their nondiabetic controls. Although DA-1229 did not affect glycemic control or insulin resistance, DA-1229 did improve lipid profiles, albuminuria and renal fibrosis. Moreover, DA-1229 treatment resulted in decreased urinary excretion of nephrin, decreased circulating and kidney DPPIV activity, and decreased macrophage infiltration in the kidney. In adriamycin-treated mice, DPPIV activity in the kidney and urinary nephrin loss were both increased, whereas glucagon-like peptide-1 concentrations were unchanged. Moreover, DA-1229 treatment significantly improved proteinuria, renal fibrosis and inflammation associated with decreased urinary nephrin loss, and kidney DPP4 activity. In cultured podocytes, DA-1229 restored the high glucose/angiotensin II-induced increase of DPPIV activity and preserved the nephrin levels in podocytes. These findings suggest that activation of DPPIV in the kidney has a role in the progression of renal disease, and that DA-1229 may exert its renoprotective effects by preventing podocyte injury.

  9. Tumor Grade

    Science.gov (United States)

    ... Other Funding Find NCI funding for small business innovation, technology transfer, and contracts Training Cancer Training at ... much of the tumor tissue has normal breast (milk) duct structures Nuclear grade : an evaluation of the ...

  10. NNDSS - Table IV. Tuberculosis

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table IV. Tuberculosis - 2014.This Table includes total number of cases reported in the United States, by region and by states, in accordance with the...

  11. NNDSS - Table IV. Tuberculosis

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table IV. Tuberculosis - 2016.This Table includes total number of cases reported in the United States, by region and by states, in accordance with the...

  12. NNDSS - Table IV. Tuberculosis

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table IV. Tuberculosis - 2015.This Table includes total number of cases reported in the United States, by region and by states, in accordance with the...

  13. Cumulative Intracranial Tumor Volume (CITV) Enhances the Prognostic Value of the Lung-Specific Graded Prognostic Assessment (GPA) Model.

    Science.gov (United States)

    Marcus, Logan P; Marshall, Deborah; Hirshman, Brian R; McCutcheon, Brandon A; Gonda, David D; Koiso, Takao; Hattangadi-Gluth, Jona A; Carter, Bob S; Yamamoto, Masaaki; Chen, Clark C

    2016-08-01

    Management of patients afflicted with brain metastasis requires tailoring of therapeutic strategies based on survival expectations. Therefore, the development of prognostic indices is of critical importance in this patient population. To determine whether the cumulative intracranial tumor volume (CITV) of brain metastasis augments the prognostic value of the lung-specific Graded Prognostic Assessment (GPA) index. Patient data were derived from 365 lung cancer patients with brain metastasis who were consecutively treated with stereotactic radiosurgery at the University of California, San Diego/San Diego Gamma Knife Center. CITV was analyzed to determine the volume cutoff that maximized sensitivity and specificity for 1-year survival. Multivariate Cox proportional hazard modeling was performed, and overall survival was estimated by the Kaplan-Meier method risk stratifying with or without this optimal CITV. The prognostic value of these models (lung-specific GPA ± CITV) was quantitatively compared with the use of net reclassification improvement (>0) and integrated discrimination improvement. For the University of California, San Diego/San Diego Gamma Knife Center cohort, the CITV cutoff that had the greatest survival discrimination at 1 year was 4 cm. The addition of CITV to the lung-specific GPA indexes significantly improved the prognostic value of lung-specific GPA, with net reclassification improvement >0 of 0.430 (95% confidence interval, 0.228-0.629) and integrated discrimination improvement of 0.029 (95% confidence interval, 0.004-0.073). These findings were validated in an independent cohort of 1638 lung cancer patients with brain metastasis who were treated with stereotactic radiosurgery at the Katsuta Hospital Mito Gamma House in Japan. In independent cohorts, the addition of CITV to the lung-specific GPA index significantly improved the prognostic value of this index. AUC, area under the receiver-operating characteristic curveBM, brain metastasis

  14. Thermodynamic data for predicting concentrations of Th(IV), U(IV), Np(IV), and Pu(IV) in geologic environments

    Energy Technology Data Exchange (ETDEWEB)

    Rai, Dhanpat; Roa, Linfeng; Weger, H.T.; Felmy, A.R. [Battelle, Pacific Northwest National Laboratory (PNNL) (United States); Choppin, G.R. [Florida State University (United States); Yui, Mikazu [Waste Isolation Research Division, Tokai Works, Japan Nuclear Cycle Development Inst., Tokai, Ibaraki (Japan)

    1999-01-01

    This report provides thermodynamic data for predicting concentrations of Th(IV), U(IV), Np(IV), and Pu(IV) in geologic environments, and contributes to an integration of the JNC chemical thermodynamic database, JNC-TDB (previously PNC-TDB), for the performance analysis of geological isolation system for high-level radioactive wastes. Thermodynamic data for the formation of complexes or compounds with hydroxide, chloride, fluoride, carbonate, nitrate, sulfate and phosphate are discussed in this report. Where data for specific actinide(IV) species was lacking, the data were selected based on chemical analogy to other tetravalent actinides. In this study, the Pitzer ion-interaction model is used to extrapolate thermodynamic constants to zero ionic strength at 25degC. (author)

  15. A computational fluid-structure interaction model to predict the biomechanical properties of the artificial functionally graded aorta.

    Science.gov (United States)

    Khosravi, Arezoo; Bani, Milad Salimi; Bahreinizade, Hossein; Karimi, Alireza

    2016-12-01

    In the present study, three layers of the ascending aorta in respect to the time and space at various blood pressures have been simulated. Two well-known commercial finite element (FE) software have used to be able to provide a range of reliable numerical results while independent on the software type. The radial displacement compared with the time as well as the peripheral stress and von Mises stress of the aorta have calculated. The aorta model was validated using the differential quadrature method (DQM) solution and, then, in order to design functionally graded materials (FGMs) with different heterogeneous indexes for the artificial vessel, two different materials have been employed. Fluid-structure interaction (FSI) simulation has been carried out on the FGM and a natural vessel of the human body. The heterogeneous index defines the variation of the length in a function. The blood pressure was considered to be a function of both the time and location. Finally, the response characteristics of functionally graded biomaterials (FGBMs) models with different values of heterogeneous material parameters were determined and compared with the behaviour of a natural vessel. The results showed a very good agreement between the numerical findings of the FGM materials and that of the natural vessel. The findings of the present study may have implications not only to understand the performance of different FGMs in bearing the stress and deformation in comparison with the natural human vessels, but also to provide information for the biomaterials expert to be able to select a suitable material as an implant for the aorta.

  16. A computational fluid–structure interaction model to predict the biomechanical properties of the artificial functionally graded aorta

    Science.gov (United States)

    Khosravi, Arezoo; Bani, Milad Salimi; Bahreinizade, Hossein; Karimi, Alireza

    2016-01-01

    In the present study, three layers of the ascending aorta in respect to the time and space at various blood pressures have been simulated. Two well-known commercial finite element (FE) software have used to be able to provide a range of reliable numerical results while independent on the software type. The radial displacement compared with the time as well as the peripheral stress and von Mises stress of the aorta have calculated. The aorta model was validated using the differential quadrature method (DQM) solution and, then, in order to design functionally graded materials (FGMs) with different heterogeneous indexes for the artificial vessel, two different materials have been employed. Fluid–structure interaction (FSI) simulation has been carried out on the FGM and a natural vessel of the human body. The heterogeneous index defines the variation of the length in a function. The blood pressure was considered to be a function of both the time and location. Finally, the response characteristics of functionally graded biomaterials (FGBMs) models with different values of heterogeneous material parameters were determined and compared with the behaviour of a natural vessel. The results showed a very good agreement between the numerical findings of the FGM materials and that of the natural vessel. The findings of the present study may have implications not only to understand the performance of different FGMs in bearing the stress and deformation in comparison with the natural human vessels, but also to provide information for the biomaterials expert to be able to select a suitable material as an implant for the aorta. PMID:27836981

  17. Classical Exchange Algebra of the Nonlinear Sigma Model on a Supercoset Target with Z2n Grading

    Institute of Scientific and Technical Information of China (English)

    KE San-Min; LI Xin-Ying; WANG Chun; YUE Rui-Hong

    2011-01-01

    The classical exchange algebra satisfied by the monodromy matrix of the nonlinear sigma model on a supercoset target with Z2n grading is derived using a first-order Hamiltonian formulation and by adding to the Lax connection terms proportional to constraints. This enables us to show that the conserved charges of the theory are in involution. When n = 2, our results coincide with the results given by Magro for the pure spinor description of AdS5 × S5 string theory (when the ghost terms are omitted).%The classical exchange algebra satisfied by the monodromy matrix of the nonlinear sigma model on a supercoset target with Z2n grading is derived using a first-order Hamiltonian formulation and by adding to the Lax connection terms proportional to constraints.This enables us to show that the conserved charges of the theory are in involution.When n =2,our results coincide with the results given by Magro for the pure spinor description of AdS5 × S5 string theory (when the ghost terms are omitted).Bena,Polchinski and Roiban[1] found an infinite number of non-local classically conserved charges for the Grecn-Schwarz superstring in AdS5 × S5 background.[2] Similar results were obtained for some other strings[3-9] that propagate in AdS space-time,as discussed in Refs.[7 9].Vallilo[10] showed that such charges also exist in the pure-spinor formalism of the superstring in AdS5 × S5.Bianchi and Klǔson[11] gave the current algebra of the pure-spinor superstring.Berkovits[12] proved that the nonlocal charges in the string theory are BRST-invariant and physical.

  18. Multidimensional Profiles of Health Status: An Application of the Grade of Membership Model to the World Health Survey

    Science.gov (United States)

    Andreotti, Alessandra; Minicuci, Nadia; Kowal, Paul; Chatterji, Somnath

    2009-01-01

    Background The World Health Organization (WHO) conducted the World Health Survey (WHS) between 2002 and 2004 in 70 countries to provide cross-population comparable data on health, health-related outcomes and risk factors. The aim of this study was to apply Grade of Membership (GoM) modelling as a means to condense extensive health information from the WHS into a set of easily understandable health profiles and to assign the degree to which an individual belongs to each profile. Principal Findings This paper described the application of the GoM models to summarize population health status using World Health Survey data. Grade of Membership analysis is a flexible, non-parametric, multivariate method, used to calculate health profiles from WHS self-reported health state and health conditions. The WHS dataset was divided into four country economic categories based on the World Bank economic groupings (high, upper-middle, lower-middle and low income economies) for separate GoM analysis. Three main health profiles were produced for each of the four areas: I. Robust; II. Intermediate; III. Frail; moreover population health, wealth and inequalities are defined for countries in each economic area as a means to put the health results into perspective. Conclusions These analyses have provided a robust method to better understand health profiles and the components which can help to identify healthy and non-healthy individuals. The obtained profiles have described concrete levels of health and have clearly delineated characteristics of healthy and non-healthy respondents. The GoM results provided both a useable way of summarising complex individual health information and a selection of intermediate determinants which can be targeted for interventions to improve health. As populations' age, and with limited budgets for additional costs for health care and social services, applying the GoM methods may assist with identifying higher risk profiles for decision-making and resource

  19. Multidimensional profiles of health status: an application of the grade of membership model to the world health survey.

    Directory of Open Access Journals (Sweden)

    Alessandra Andreotti

    Full Text Available BACKGROUND: The World Health Organization (WHO conducted the World Health Survey (WHS between 2002 and 2004 in 70 countries to provide cross-population comparable data on health, health-related outcomes and risk factors. The aim of this study was to apply Grade of Membership (GoM modelling as a means to condense extensive health information from the WHS into a set of easily understandable health profiles and to assign the degree to which an individual belongs to each profile. PRINCIPAL FINDINGS: This paper described the application of the GoM models to summarize population health status using World Health Survey data. Grade of Membership analysis is a flexible, non-parametric, multivariate method, used to calculate health profiles from WHS self-reported health state and health conditions. The WHS dataset was divided into four country economic categories based on the World Bank economic groupings (high, upper-middle, lower-middle and low income economies for separate GoM analysis. Three main health profiles were produced for each of the four areas: I. Robust; II. Intermediate; III. Frail; moreover population health, wealth and inequalities are defined for countries in each economic area as a means to put the health results into perspective. CONCLUSIONS: These analyses have provided a robust method to better understand health profiles and the components which can help to identify healthy and non-healthy individuals. The obtained profiles have described concrete levels of health and have clearly delineated characteristics of healthy and non-healthy respondents. The GoM results provided both a useable way of summarising complex individual health information and a selection of intermediate determinants which can be targeted for interventions to improve health. As populations' age, and with limited budgets for additional costs for health care and social services, applying the GoM methods may assist with identifying higher risk profiles for decision

  20. Interplanetary Type IV Bursts

    CERN Document Server

    Hillaris, Alexander; Nindos, Alexander

    2016-01-01

    In this work we study the characteristics of moving type IV radio bursts which extend to the hectometric wavelengths (interplanetary type IV or type IV IP bursts) and their relationship with energetic phenomena on the Sun. Our dataset comprised 48 Interplanetary type IV bursts observed by the Wind/WAVES in the 13.825 MHz?20 KHz frequency range. The dynamic spec tra of the RSTN, DAM, ARTEMIS-IV, CULGOORA, Hiraiso and IZMIRAN Radio-spectrographs were used to track the evolution of the events in the low corona; these were supplemented with SXR ?ux recordings from GOES and CME data from LASCO. Positional information for the coronal bursts were obtained by the Nan\\c{c}ay radioheliograph (NRH). We examined the relationship of the type IV events with coronal radio bursts, CMEs and SXR ?ares. The majority of the events (45) were characterized as compact; their duration was on average 106 min. This type of events were, mostly, associated with M and X class ?ares (40 out of 45) and fast CMEs; 32 of these events had CME...

  1. A thermodynamic model of nickel smelting and direct high-grade nickel matte smelting processes: Part I. Model development and validation

    Science.gov (United States)

    Tan, Pengfu; Neuschütz, Dieter

    2001-04-01

    A thermodynamic model has been developed to predict the distribution behavior of Ni, Cu, Co, Fe, S, As, Sb, and Bi in the Outokumpu flash-smelting process, the Outokumpu direct high-grade matte smelting process, and the INCO flash-smelting process. In this model, as many as 16 elements (Ni, Cu, Co, Fe, As, Sb, Bi, S, O, Al, Ca, Mg, Si, N, C, and H) are considered, and two nickel sulfide species are used to allow for modeling of sulfur-deficient mattes. The compositions of the matte, slag, and gaseous phases in equilibrium are calculated using Gibbs free energies of formation and the activity coefficients of the components derived from the experimental data. The model predictions are compared with the known industrial data from the Kalgoorlie Nickel Smelter (Kalgoorlie, Australia), the Outokumpu Harjavalta Nickel Smelter (Harjavalta, Finland), the INCO Metals Company (Sudbury, Canada), and from a number of experimental data. An excellent agreement is obtained. It was found that the distribution behaviors of Ni, Co, Cu, Fe, S, As, Sb, and Bi in the nickel smelting furnace depend on process parameters such as the smelting temperature, matte grade, and partial pressure of oxygen in the process.

  2. Experimental analysis and modeling of the IV characteristics of photovoltaic solar cells under solar spectrum spot illumination

    Energy Technology Data Exchange (ETDEWEB)

    Munji, M.K., E-mail: mathew.munji@nmmu.ac.z [Department of Physics, Nelson Mandela Metropolitan University, PO Box 7700 Port Elizabeth 6031 (South Africa); Dyk, E.E. van; Vorster, F.J. [Department of Physics, Nelson Mandela Metropolitan University, PO Box 7700 Port Elizabeth 6031 (South Africa)

    2009-12-01

    In this paper, some models that have been put forward to explain the characteristics of a photovoltaic solar cell device under solar spot-illumination are investigated. In the experimental procedure, small areas of the cell were selected and illuminated at different solar intensities. The solar cell open circuit voltage (V{sub oc}) and short circuit current (I{sub sc}) obtained at different illumination intensities was used to determine the solar cell ideality factor. By varying the illuminated area on the solar cell, changes in the ideality factor were studied. The ideality factor obtained increases with decreasing illumination surface ratio. The photo-generated current at the illuminated part of the cell is assumed to act as a dc source that injects charge carriers into the p-n junction of the whole solar cell while the dark region of the solar cell operates in a low space charge recombination regime with small diffusion currents. From this analysis, a different model of a spot illuminated cell that uses the variation of ideality factor with the illuminated area is proposed.

  3. Comparative modeling of combined transport of water and graded-size molecules across the glomerular capillary wall.

    Science.gov (United States)

    Abdel-Mageed, Samir M; Mohamed, Ehab I

    2016-04-07

    Chronic kidney disease is a common and growing problem worldwide that necessitates recognition of individual risk and appropriate laboratory testing before its progression to end-stage renal failure, requiring dialysis or transplantation for survival. Clearance studies using various graded-size probe molecules established that the passage of molecules/proteins across the glomerular capillary barrier of mammalian kidneys is increasingly restricted as their size increase. Few mathematical models were developed to describe the dynamics of the size-selective functions of macromolecules across membranes and gelatins. In the present study, we compare the behavior of three mathematical descriptions for the Fiber Matrix theory, an Extended Fiber Matrix theory, and an Alternative Statistical Physics analysis to describe the size-selective function of the glomerular capillary barrier; using mainly its hemodynamic, morphometric and hydrodynamic variables; in two experimental rat models. The glomerular basement membrane was represented as a homogeneous three-dimensional network of fibers of uniform length (Lf), radius (Rf), total fractional solid volume of fibers (Vf) and characteristic Darcy permeability. The models were appropriate for simulating in vivo fractional clearance data of neutral Dextran and Ficoll macromolecules from two experimental rat models. We believe that the Lf, Rf and Vf best-fit numerical values may signify new insights for the diagnosis of human nephropathies.

  4. Mathematical modeling of static layer crystallization for propellant grade hydrogen peroxide

    Science.gov (United States)

    Hao, Lin; Chen, Xinghua; Sun, Yaozhou; Liu, Yangyang; Li, Shuai; Zhang, Mengqian

    2017-07-01

    Hydrogen peroxide (H2O2) is an important raw material widely used in many fields. In this work a mathematical model of heat conduction with a moving boundary was proposed to study the melt crystallization process of hydrogen peroxide which was carried out outside a cylindrical crystallizer. Considering the effects of the temperature of the cooling fluid on the thermal conductivity of crude crystal, the model is an improvement of Guardani's research and can be solved by analytic iteration method. An experiment was designed to measure the thickness of crystal layer with time under different conditions. A series of analysis, including the effects of different refrigerant temperature on crystal growth rate, the effects of different cooling rates on crystal layer growth rate, the effects of crystallization temperature on heat transfer and the model's application scope were conducted based on the comparison between experimental results and simulation results of the model.

  5. A Mathematical Model For Sorting the Grades 3 + X Entrance Examination%高考3+X成绩排序的一个数学模型

    Institute of Scientific and Technical Information of China (English)

    谢乐军; 李伟良; 陈永辉; 李海荣

    2001-01-01

    建立了高考3+x成绩一个排序模型,模型的参数便于高等院校根据学校的特点确定其取值.且该模型给出了考生的一个模型分数,按此分数排序决定考生录取次序,可做到"公平公正、择优录取"%This paper built a mathematical model for sorting the grades of 3 + X entrance examination. Themodel parameters are designed for colleges easy to select examinees. In order to sort the examinees this model set ex-aminee a model grade. This grade may do fair and square in justice to examinees.

  6. Analytical Models of Exoplanetary Atmospheres. IV. Improved Two-stream Radiative Transfer for the Treatment of Aerosols

    Science.gov (United States)

    Heng, Kevin; Kitzmann, Daniel

    2017-10-01

    We present a novel generalization of the two-stream method of radiative transfer, which allows for the accurate treatment of radiative transfer in the presence of strong infrared scattering by aerosols. We prove that this generalization involves only a simple modification of the coupling coefficients and transmission functions in the hemispheric two-stream method. This modification originates from allowing the ratio of the first Eddington coefficients to depart from unity. At the heart of the method is the fact that this ratio may be computed once and for all over the entire range of values of the single-scattering albedo and scattering asymmetry factor. We benchmark our improved two-stream method by calculating the fraction of flux reflected by a single atmospheric layer (the reflectivity) and comparing these calculations to those performed using a 32-stream discrete-ordinates method. We further compare our improved two-stream method to the two-stream source function (16 streams) and delta-Eddington methods, demonstrating that it is often more accurate at the order-of-magnitude level. Finally, we illustrate its accuracy using a toy model of the early Martian atmosphere hosting a cloud layer composed of carbon dioxide ice particles. The simplicity of implementation and accuracy of our improved two-stream method renders it suitable for implementation in three-dimensional general circulation models. In other words, our improved two-stream method has the ease of implementation of a standard two-stream method, but the accuracy of a 32-stream method.

  7. A score model for the continuous grading of early allograft dysfunction severity.

    Science.gov (United States)

    Pareja, Eugenia; Cortes, Miriam; Hervás, David; Mir, José; Valdivieso, Andrés; Castell, José V; Lahoz, Agustín

    2015-01-01

    Early allograft dysfunction (EAD) dramatically influences graft and patient outcomes. A lack of consensus on an EAD definition hinders comparisons of liver transplant outcomes and management of recipients among and within centers. We sought to develop a model for the quantitative assessment of early allograft function [Model for Early Allograft Function Scoring (MEAF)] after transplantation. A retrospective study including 1026 consecutive liver transplants was performed for MEAF score development. Multivariate data analysis was used to select a small number of postoperative variables that adequately describe EAD. Then, the distribution of these variables was mathematically modeled to assign a score for each actual variable value. A model, based on easily obtainable clinical parameters (ie, alanine aminotransferase, international normalized ratio, and bilirubin) and scoring liver function from 0 to 10, was built. The MEAF score showed a significant association with patient and graft survival at 3-, 6- and 12-month follow-ups. Hepatic steatosis and age for donors; cold/warm ischemia times and postreperfusion syndrome for surgery; and intensive care unit and hospital stays, Model for End-Stage Liver Disease and Child-Pugh scores, body mass index, and fresh frozen plasma transfusions for recipients were factors associated significantly with EAD. The model was satisfactorily validated by its application to an independent set of 200 patients who underwent liver transplantation at a different center. In conclusion, a model for the quantitative assessment of EAD severity has been developed and validated for the first time. The MEAF provides a more accurate graft function assessment than current categorical classifications and may help clinicians to make early enough decisions on retransplantation benefits. Furthermore, the MEAF score is a predictor of recipient and graft survival. The standardization of the criteria used to define EAD may allow reliable comparisons of

  8. Modeling of Nitrogen Penetration in Medical Grade CoCrMo Alloy during Plasma Nitriding

    Directory of Open Access Journals (Sweden)

    Arvaidas GALDIKAS

    2014-04-01

    Full Text Available For analysis of plasma nitriding process and nitrogen penetration into CoCrMo alloy the trapping-detrapping model is applied. This model is commonly used for analysis of stainless steel nitriding, however, in this work it is shown that the same nitrogen penetration mechanism takes place in CoCrMo alloys. From the fitting of experimental curves, taken from literature, it is found by the proposed model that diffusion coefficient depends on nitrogen concentration according to Einstein-Smoluchowski relation D µ 1/CN. The diffusion coefficients for 400oC temperature nitriding of in CoCrMo are calculated. The shape of nitrogen depth profile curves are analyzed showing influence of different parameters such as detrapping activation energy, chromium concentration, etc.DOI: http://dx.doi.org/10.5755/j01.ms.20.1.3458

  9. Modeling of Nitrogen Penetration in Medical Grade CoCrMo Alloy during Plasma Nitriding

    Directory of Open Access Journals (Sweden)

    Arvaidas GALDIKAS

    2014-04-01

    Full Text Available For analysis of plasma nitriding process and nitrogen penetration into CoCrMo alloy the trapping-detrapping model is applied. This model is commonly used for analysis of stainless steel nitriding, however, in this work it is shown that the same nitrogen penetration mechanism takes place in CoCrMo alloys. From the fitting of experimental curves, taken from literature, it is found by the proposed model that diffusion coefficient depends on nitrogen concentration according to Einstein-Smoluchowski relation D µ 1/CN. The diffusion coefficients for 400oC temperature nitriding of in CoCrMo are calculated. The shape of nitrogen depth profile curves are analyzed showing influence of different parameters such as detrapping activation energy, chromium concentration, etc.DOI: http://dx.doi.org/10.5755/j01.ms.20.1.3458

  10. Modeling variability and uncertainty associated with inhaled weapons-grade PuO2.

    Science.gov (United States)

    Aden, James; Scott, Bobby R

    2003-06-01

    The work presented relates to developing a stochastic version of the ICRP 66 respiratory tract deposition model and applying the stochastic model to characterize the variability/uncertainty associated with inhaled PuO2 for a hypothetical population of nuclear workers engaged in light work-related exercise. The parameter uncertainty/variability distributions used are essentially the same as the FORTRAN-based stochastic deposition model of Bolch et al. known as LUDUC (LUng Dose Uncertainty Code). Based on Crystal Ball software, this stochastic deposition model includes particle polydispersity, which Bolch et al. did not discuss. This paper first compares model-simulated regional deposition probability distributions to deterministic results based on LUDEP (LUng Dose Evaluation Program) software, which implements the ICRP 66 deterministic deposition model. For these comparisons, a particle density of 3 g cm(-3) (for hypothetical radioactive particles) was used. The range of possible depositions generated by LUDUC and the Crystal Ball program results revealed LUDEP's limitations. Even though LUDEP tends to use parameters that represent average parameter values for adult males, it overestimates deposition in the lower regions of the lung for most of the population. The Crystal Ball program was then used to generate radioactivity intake distributions for single and multiple PuO2 particle intakes by a hypothetical population of nuclear workers for the stochastic intake (STI) paradigm. These distributions of radioactivity intake are evaluated for the five primary regions of the respiratory tract as defined in the ICRP Publication 66. The results reveal that when a particle has been deposited, the radioactivity is likely to be low if it is in the lower regions (< 10 Bq for the bb and AI regions), but it may be quite large in the upper regions (as much as 600 Bq for the ET1, and ET2 regions), and the distributions for radioactivity become less and less skewed to the right, as

  11. Radiative transfer in a clumpy universe: IV. New synthesis models of the cosmic UV/X-ray background

    CERN Document Server

    Haardt, Francesco

    2011-01-01

    We present improved synthesis models of the evolving spectrum of the UV/X-ray diffuse background, updating and extending our previous results. Five new main components are added to our radiative transfer code CUBA: (1) the sawtooth modulation of the background intensity from resonant line absorption in the Lyman series of cosmic hydrogen and helium; (2) the X-ray emission from obscured and unobscured quasars; (3) a piecewise parameterization of the distribution in redshift and column density of intergalactic absorbers that fits recent measurements of the mean free path of 1 ryd photons; (4) an accurate treatment of the photoionization structure of absorbers; and (5) the UV emission from star-forming galaxies at all redshifts. We provide tables of the predicted HI and HeII photoionization and photoheating rates for use, e.g., in cosmological hydrodynamics simulations of the Lya forest, and a new metallicity-dependent calibration to the UV luminosity density-star formation rate density relation. A "minimal cosm...

  12. Noncontact dipole effects on channel permeation. IV. Kinetic model of 5F-Trp(13) gramicidin A currents.

    Science.gov (United States)

    Thompson, N; Thompson, G; Cole, C D; Cotten, M; Cross, T A; Busath, D D

    2001-09-01

    Nonlinear least squares fitting was used to assign rate constants for the three-barrier, two-site, double-occupancy, single-filing kinetic model for previously reported current-voltage relations of (5F-Indole)Trp(13) gramicidin A and gramicidin A channels (, 75:2830-2844). By judicious coupling of parameters, it was possible to reduce the parameter space from 64 parameters to 24, and a reasonable fit consistent with other experimental data was obtained. The main features of the fit were that fluorination increased the rate constant for translocation by a factor of 2.33, consistent with a free energy change in the translocation barrier of -0.50 kcal/mol, and increased first-ion binding affinity by a factor of 1.13, primarily by decreasing the first-ion exit rate constant. The translocation rate constant was 5.62 times slower in diphytanoyl phosphatidylcholine (DPhPC) bilayers than in monoolein (GMO) bilayers (coupled for the four combinations of peptide and salt), suggesting a 44.2-mV difference in the projection of the interfacial dipole into the channel. Thus fluorination caused increased currents in DPhPC bilayers, where a high interfacial dipole potential makes translocation more rate limiting because the translocation barrier was reduced, and decreased currents in GMO bilayers, where ion exit or entry is rate limiting because these barriers were increased.

  13. Toxicokinetic-toxicodynamic modeling of quantal and graded sublethal endpoints: a brief discussion of concepts

    NARCIS (Netherlands)

    Ashauer, R.; Agatz, A.; Albert, C.; Ducrot, V.; Galic, N.G.; Hendriks, J.; Jager, T.; Kretschmann, A.; O'Connor, I.; Rubach, M.N.; Nyman, M.; Schmitt, W.; Stadnicka, J.; Brink, van den P.J.

    2011-01-01

    We report on the advantages and problems of using toxicokinetic-toxicodynamic (TKTD) models for the analysis, understanding, and simulation of sublethal effects. Only a few toxicodynamic approaches for sublethal effects are available. These differ in their effect mechanism and emphasis on linkages b

  14. Toxicokinetic-toxicodynamic modeling of quantal and graded sublethal endpoints: a brief discussion of concepts

    NARCIS (Netherlands)

    Ashauer, R.; Agatz, A.; Albert, C.; Ducrot, V.; Galic, N.G.; Hendriks, J.; Jager, T.; Kretschmann, A.; O'Connor, I.; Rubach, M.N.; Nyman, M.; Schmitt, W.; Stadnicka, J.; Brink, van den P.J.

    2011-01-01

    We report on the advantages and problems of using toxicokinetic-toxicodynamic (TKTD) models for the analysis, understanding, and simulation of sublethal effects. Only a few toxicodynamic approaches for sublethal effects are available. These differ in their effect mechanism and emphasis on linkages

  15. Topic Teamwork: A Collaborative Integrative Model for Increasing Student-Centered Learning in Grades K-12.

    Science.gov (United States)

    Christie, Brett

    2000-01-01

    Describes the benefits of "topic teamwork," an interdisciplinary model designed to make integrative teaching a well-structured, cooperative effort involving all teachers and students. The article presents examples of and strategies for integrating physical education with other subject areas and for assessing topic teamwork, concluding that topic…

  16. The Ionized Gas and Nuclear Environment in NGC 3783. IV. Variability and Modeling of the 900 Kilosecond Chandra Spectrum

    Science.gov (United States)

    Netzer, Hagai; Kaspi, Shai; Behar, Ehud; Brandt, W. N.; Chelouche, Doron; George, Ian M.; Crenshaw, D. Michael; Gabel, Jack R.; Hamann, Frederick W.; Kraemer, Steven B.; Kriss, Gerard A.; Nandra, Kirpal; Peterson, Bradley M.; Shields, Joseph C.; Turner, T. J.

    2003-12-01

    We present a detailed spectral analysis of the data obtained from NGC 3783 during the period 2000-2001 using Chandra. The data were split in various ways to look for time- and luminosity-dependent spectral variations. This analysis, along with the measured equivalent widths of a large number of X-ray lines and photoionization calculations, lead us to the following results and conclusions. (1) NGC 3783 fluctuated in luminosity by a factor of ~1.5 during individual observations (most of which were of 170 ks duration). These fluctuations were not associated with significant spectral variations. (2) On a longer timescale (20-120 days), we found the source to exhibit two very different spectral shapes. The main difference between these can be well-described by the appearance (in the ``high state'') and disappearance (in the ``low state'') of a spectral component that dominates the underlying continuum at the longest wavelengths. Contrary to the case in other objects, the spectral variations are not related to the brightening or the fading of the continuum at short wavelengths in any simple way. NGC 3783 seems to be the first active galactic nucleus (AGN) to show this unusual behavior. (3) The appearance of the soft continuum component is consistent with being the only spectral variation, and there is no need to invoke changes in the opacity of the absorbers lying along the line of sight. Indeed, we find that all the absorption lines that can be reliably measured have the same equivalent widths (within the observational uncertainties) during high and low states. (4) Photoionization modeling indicates that a combination of three ionized absorbers, each split into two kinematic components, can explain the strengths of almost all the absorption lines and bound-free edges. These three components span a large range of ionization and have total column of about 4×1022 cm-2. Moreover, all three components are thermally stable and seem to have the same gas pressure. Thus, all

  17. One-dimensional breakdown voltage model of SOI RESURF lateral power device based on lateral linearly graded approximation

    Institute of Scientific and Technical Information of China (English)

    张珺; 郭宇锋; 徐跃; 林宏; 杨慧; 洪洋; 姚佳飞

    2015-01-01

    A novel one-dimensional (1D) analytical model is proposed for quantifying the breakdown voltage of reduced surface field (RESURF) lateral power device fabricated on silicon on an insulator (SOI) substrate. We assume that the charges in the depletion region contribute to the lateral PN junctions along the diagonal of the area shared by the lateral and vertical depletion regions. Based on the assumption, the lateral PN junction behaves as a linearly graded junction, thus resulting in a reduced surface electric field and high breakdown voltage. Using the proposed model, the breakdown voltage as a function of device parameters is investigated and compared with the numerical simulation by the TCAD tools. The analytical results are shown to be in fair agreement with the numerical results. Finally, a new RESURF criterion is derived which offers a useful scheme to optimize the structure parameters. This simple 1D model provides a clear physical insight into the RESURF effect and a new explanation on the improvement in breakdown voltage in an SOI RESURF device.

  18. Adhesive contact on power-law graded elastic solids: The JKR-DMT transition using a double-Hertz model

    Science.gov (United States)

    Jin, Fan; Guo, Xu; Gao, Huajian

    2013-12-01

    A cohesive zone model of axisymmetric adhesive contact between a rigid sphere and a power-law graded elastic half-space is established by extending the double-Hertz model of Greenwood and Johnson (1998). Closed-form solutions are obtained analytically for the surface stress, deformation fields and equilibrium relations among applied load, indentation depth, inner and outer radii of the cohesive zone, which include the corresponding solutions for homogeneous isotropic materials and the Gibson solid as special cases. These solutions provide a continuous transition between JKR and DMT type contact models through a generalized Tabor parameter μ. Our analysis reveals that the magnitude of the pull-off force ranges from (3+k)πRΔγ/2 to 2πRΔγ, where k, R and Δγ denote the gradient exponent of the elastic modulus for the half-space, the radius of the sphere and the work of adhesion, respectively. Interestingly, the pull-off force for the Gibson solid is found to be identically equal to 2πRΔγ, independent of the corresponding Tabor parameter. The obtained analytical solutions are validated with finite element simulations.

  19. The Liquid Metallic Hydrogen Model of the Sun and the Solar Atmosphere IV. On the Nature of the Chromosphere

    Directory of Open Access Journals (Sweden)

    Robitaille P.-M.

    2013-07-01

    Full Text Available The chromosphere is the site of weak emission lines characterizing the flash spectrum observed for a few seconds during a total eclipse. This layer of the solar atmosphere is known to possess an opaque Hα emission and a great number of spicules, which can extend well above the photosphere. A stunning variety of hydrogen emission lines have been observed in this region. The production of these lines has provided the seventeenth line of evidence that the Sun is comprised of condensed matter (Robitaille P.M. Liquid Metallic Hydrogen II: A critical assessment of current and primordial helium levels in Sun. Progr. Phys., 2013, v. 2, 35–47. Contrary to the gaseous solar models, the simplest mechanism for the production of emission lines is the evaporation of excited atoms from condensed surfaces existing within the chromosphere, as found in spicules. This is reminiscent of the chemiluminescence which occurs during the condensation of silver clusters (Konig L., Rabin I., Schultze W., and Ertl G. Chemiluminescence in the Agglomeration of Metal Clusters. Science, v. 274, no. 5291, 1353–1355. The process associated with spicule formation is an exothermic one, requiring the transport of energy away from the site of condensation. As atoms leave localized surfaces, their electrons can occupy any energy level and, hence, a wide variety of emission lines are produced. In this regard, it is hypothesized that the presence of hydrides on the Sun can also facilitate hydrogen condensation in the chromosphere. The associated line emission from main group and transition elements constitutes the thirtieth line of evidence that the Sun is condensed matter. Condensation processes also help to explain why spicules manifest an apparently constant temperature over their entire length. Since the corona supports magnetic field lines, the random orientations associated with spicule formation suggests that the hydrogen condensates in the chromosphere are not metallic in

  20. Interplanetary Type IV Bursts

    Science.gov (United States)

    Hillaris, A.; Bouratzis, C.; Nindos, A.

    2016-08-01

    We study the characteristics of moving type IV radio bursts that extend to hectometric wavelengths (interplanetary type IV or type {IV}_{{IP}} bursts) and their relationship with energetic phenomena on the Sun. Our dataset comprises 48 interplanetary type IV bursts observed with the Radio and Plasma Wave Investigation (WAVES) instrument onboard Wind in the 13.825 MHz - 20 kHz frequency range. The dynamic spectra of the Radio Solar Telescope Network (RSTN), the Nançay Decametric Array (DAM), the Appareil de Routine pour le Traitement et l' Enregistrement Magnetique de l' Information Spectral (ARTEMIS-IV), the Culgoora, Hiraso, and the Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation (IZMIRAN) Radio Spectrographs were used to track the evolution of the events in the low corona. These were supplemented with soft X-ray (SXR) flux-measurements from the Geostationary Operational Environmental Satellite (GOES) and coronal mass ejections (CME) data from the Large Angle and Spectroscopic Coronagraph (LASCO) onboard the Solar and Heliospheric Observatory (SOHO). Positional information of the coronal bursts was obtained by the Nançay Radioheliograph (NRH). We examined the relationship of the type IV events with coronal radio bursts, CMEs, and SXR flares. The majority of the events (45) were characterized as compact, their duration was on average 106 minutes. This type of events was, mostly, associated with M- and X-class flares (40 out of 45) and fast CMEs, 32 of these events had CMEs faster than 1000 km s^{-1}. Furthermore, in 43 compact events the CME was possibly subjected to reduced aerodynamic drag as it was propagating in the wake of a previous CME. A minority (three) of long-lived type {IV}_{{IP}} bursts was detected, with durations from 960 minutes to 115 hours. These events are referred to as extended or long duration and appear to replenish their energetic electron content, possibly from electrons escaping from the corresponding coronal

  1. A model of pyrolysis in a staged scheme of low-grade solid fuel gasification

    Science.gov (United States)

    Levin, A. A.; Shamansky, V. A.; Kozlov, A. N.

    2016-10-01

    The development and evolution of the theory of solid fuel combustion took place in the mid-20th century. The most studied research subject was sized fossil coal. At the same time the research on the fuels with a high yield of volatile matter (biomass) was limited due to insufficient data on kinetics of physical and chemical processes that occur at their heating. Obviously, the creation of a prospective low-tonnage technology for staged gasification of wooden biomass is possible only when a detailed mechanism of these processes is well understood and their kinetic parameters are known. This paper presents the initial results of the development of a model of wood pyrolysis in a screw reactor as the first stage of the multistage gasification process. One of the currently set goals in this research is to develop a mathematical model of heat and mass transfer processes to perform optimization calculations.

  2. Predicting DPP-IV inhibitors with machine learning approaches

    Science.gov (United States)

    Cai, Jie; Li, Chanjuan; Liu, Zhihong; Du, Jiewen; Ye, Jiming; Gu, Qiong; Xu, Jun

    2017-04-01

    Dipeptidyl peptidase IV (DPP-IV) is a promising Type 2 diabetes mellitus (T2DM) drug target. DPP-IV inhibitors prolong the action of glucagon-like peptide-1 (GLP-1) and gastric inhibitory peptide (GIP), improve glucose homeostasis without weight gain, edema, and hypoglycemia. However, the marketed DPP-IV inhibitors have adverse effects such as nasopharyngitis, headache, nausea, hypersensitivity, skin reactions and pancreatitis. Therefore, it is still expected for novel DPP-IV inhibitors with minimal adverse effects. The scaffolds of existing DPP-IV inhibitors are structurally diversified. This makes it difficult to build virtual screening models based upon the known DPP-IV inhibitor libraries using conventional QSAR approaches. In this paper, we report a new strategy to predict DPP-IV inhibitors with machine learning approaches involving naïve Bayesian (NB) and recursive partitioning (RP) methods. We built 247 machine learning models based on 1307 known DPP-IV inhibitors with optimized molecular properties and topological fingerprints as descriptors. The overall predictive accuracies of the optimized models were greater than 80%. An external test set, composed of 65 recently reported compounds, was employed to validate the optimized models. The results demonstrated that both NB and RP models have a good predictive ability based on different combinations of descriptors. Twenty "good" and twenty "bad" structural fragments for DPP-IV inhibitors can also be derived from these models for inspiring the new DPP-IV inhibitor scaffold design.

  3. Predicting DPP-IV inhibitors with machine learning approaches

    Science.gov (United States)

    Cai, Jie; Li, Chanjuan; Liu, Zhihong; Du, Jiewen; Ye, Jiming; Gu, Qiong; Xu, Jun

    2017-02-01

    Dipeptidyl peptidase IV (DPP-IV) is a promising Type 2 diabetes mellitus (T2DM) drug target. DPP-IV inhibitors prolong the action of glucagon-like peptide-1 (GLP-1) and gastric inhibitory peptide (GIP), improve glucose homeostasis without weight gain, edema, and hypoglycemia. However, the marketed DPP-IV inhibitors have adverse effects such as nasopharyngitis, headache, nausea, hypersensitivity, skin reactions and pancreatitis. Therefore, it is still expected for novel DPP-IV inhibitors with minimal adverse effects. The scaffolds of existing DPP-IV inhibitors are structurally diversified. This makes it difficult to build virtual screening models based upon the known DPP-IV inhibitor libraries using conventional QSAR approaches. In this paper, we report a new strategy to predict DPP-IV inhibitors with machine learning approaches involving naïve Bayesian (NB) and recursive partitioning (RP) methods. We built 247 machine learning models based on 1307 known DPP-IV inhibitors with optimized molecular properties and topological fingerprints as descriptors. The overall predictive accuracies of the optimized models were greater than 80%. An external test set, composed of 65 recently reported compounds, was employed to validate the optimized models. The results demonstrated that both NB and RP models have a good predictive ability based on different combinations of descriptors. Twenty "good" and twenty "bad" structural fragments for DPP-IV inhibitors can also be derived from these models for inspiring the new DPP-IV inhibitor scaffold design.

  4. Zebrafish as a Model System for Environmental Health Studies in the Grade 9–12 Classroom

    OpenAIRE

    Tomasiewicz, Henry G.; Hesselbach, Renee; Carvan, Michael John; Goldberg, Barbara; Berg, Craig A.; Petering, David H.

    2014-01-01

    Developing zebrafish embryos were used as a model system for high school students to conduct scientific investigations that reveal features of normal development and to test how different environmental toxicants impact the developmental process. The primary goal of the module was to engage students from a wide range of socio-economic backgrounds, with particular focus on underserved inner-city high schools, in inquiry-based learning and hands-on experimentation. In addition, the module served...

  5. Modeling and analysis of a transcritical rankine power cycle with a low grade heat source

    DEFF Research Database (Denmark)

    Nguyen, Chan; Veje, Christian

    2011-01-01

    A transcritical carbon dioxide (CO2) Rankine power cycle has been analyzed based on first and second law of thermodynamics. Detailed simulations using distributed models for the heat exchangers have been performed in order to develop the performance characteristics in terms of e.g., thermal effic...... conditions for the high side pressure. In addition the results underline that the investment cost for additional heat exchange components such as an internal heat exchanger may be unprofitable in the case where the heat source is free.......A transcritical carbon dioxide (CO2) Rankine power cycle has been analyzed based on first and second law of thermodynamics. Detailed simulations using distributed models for the heat exchangers have been performed in order to develop the performance characteristics in terms of e.g., thermal...... efficiency, exergetic efficiency and specific net power output. A generic cycle configuration has been used for analysis of a geothermal energy heat source. This model has been validated against similar calculations using industrial waste heat as the energy source. Calculations are done with fixed...

  6. Zebrafish as a model system for environmental health studies in the grade 9-12 classroom.

    Science.gov (United States)

    Tomasiewicz, Henry G; Hesselbach, Renee; Carvan, Michael John; Goldberg, Barbara; Berg, Craig A; Petering, David H

    2014-08-01

    Developing zebrafish embryos were used as a model system for high school students to conduct scientific investigations that reveal features of normal development and to test how different environmental toxicants impact the developmental process. The primary goal of the module was to engage students from a wide range of socio-economic backgrounds, with particular focus on underserved inner-city high schools, in inquiry-based learning and hands-on experimentation. In addition, the module served as a platform for both teachers and students to design additional inquiry-based experiments. In this module, students spawned adult zebrafish to generate developing embryos, exposed the embryos to various toxicants, then gathered, and analyzed data obtained from control and experimental embryos. The module provided a flexible, experimental framework for students to test the effects of numerous environmental toxicants, such as ethanol, caffeine, and nicotine, on the development of a model vertebrate organism. Students also observed the effects of dose on experimental outcomes. From observations of the effects of the chemical agents on vertebrate embryos, students drew conclusions on how these chemicals could impact human development and health. Results of pre-tests and post-tests completed by participating students indicate statistically significant changes in awareness of the impact of environmental agents on fish and human beings In addition, the program's evaluator concluded that participation in the module resulted in significant changes in the attitude of students and teachers toward science in general and environmental health in particular.

  7. Model for neutron total cross-section at low energies for nuclear grade graphite

    Energy Technology Data Exchange (ETDEWEB)

    Galván Josa, V.M. [Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), FaMAF, Universidad Nacional de Córdoba (Argentina); Dawidowski, J., E-mail: javier@cab.cnea.gov.ar [Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Comisión Nacional de Enegía Atómica-Universidad Nacional de Cuyo (Argentina); Santisteban, J.R.; Malamud, F. [Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Comisión Nacional de Enegía Atómica-Universidad Nacional de Cuyo (Argentina); Oliveira, R.G. [Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), CIQUIBIC, Fac. Cs. Químicas, Universidad Nacional de Córdoba (Argentina)

    2015-04-21

    At subthermal neutron energies, polycrystalline graphite shows a large total cross-section due to small angle scattering processes. In this work, a new methodology to determine pore size distributions through the neutron transmission technique at subthermal energies is proposed and its sensitivity is compared with standard techniques. A simple model based on the form factor for spherical particles, normally used in the Small Angle Neutron Scattering technique, is employed to calculate the contribution of small angle effect to the total scattering cross-section, with the width and center of the radii distributions as free parameters in the model. Small Angle X-ray Scattering experiments were performed to compare results as a means to validate the method. The good agreement reached reveals that the neutron transmission technique is a useful tool to explore small angle scattering effects. This fact can be exploited in situations where large samples must be scanned and it is difficult to investigate them with conventional methods. It also opens the possibility to apply this method in energy-resolved neutron imaging. Also, since subthermal neutron transmission experiments are perfectly feasible in small neutron sources, the present findings open new possibilities to the work done in such kind of facilities.

  8. Borderline and avoidant personality disorders and the five-factor model of personality: a comparison between DSM-IV diagnoses and NEO-PI-R.

    Science.gov (United States)

    Wilberg, T; Urnes, O; Friis, S; Pedersen, G; Karterud, S

    1999-01-01

    A self-report measure of the Five-Factor Model (FFM) of personality, NEO-PI-R, was administered to a sample of patients with borderline (BPD, N = 29) or avoidant PD (AVPD, N = 34), admitted to a day treatment program, to investigate the NEO-PI-R profiles of the disorders, and the ability of NEO-PI-R to discriminate between the two disorders. The diagnoses were assessed according to the LEAD standard. AVPD was associated with high levels of Neuroticism and Agreeableness, and low levels of Extraversion and Conscientiousness. BPD was associated with high levels of Neuroticism and low levels of Agreeableness, Extraversion, and Conscientiousness. Eighty-eight percent of the AVPD group had high scores on Neuroticism and low scores on Extraversion, whereas 65% of the BPD group were high on Neuroticism and low on Agreeableness. The Extraversion and Agreeableness scales of NEO-PI-R discriminated between patients with BPD and those with AVPD. Patients with BPD scored significantly higher on the Angry Hostility and Impulsiveness subscales of Neuroticism and significantly lower on three Extraversion subscales, three Agreeableness subscales, and one Conscientiousness subscale. At the DSM-IV criterion level, there were more significant relationships between the subscales of NEO-PI-R and the AVPD criteria than with the BPD criteria. The findings suggest that the FFM has good discriminating ability regarding BPD and AVPD. However, there may be a closer conceptual relationship between the FFM and AVPD than between the FFM and BPD.

  9. Segmentation of solid subregion of high grade gliomas in MRI images based on active contour model (ACM)

    Science.gov (United States)

    Seow, P.; Win, M. T.; Wong, J. H. D.; Abdullah, N. A.; Ramli, N.

    2016-03-01

    Gliomas are tumours arising from the interstitial tissue of the brain which are heterogeneous, infiltrative and possess ill-defined borders. Tumour subregions (e.g. solid enhancing part, edema and necrosis) are often used for tumour characterisation. Tumour demarcation into substructures facilitates glioma staging and provides essential information. Manual segmentation had several drawbacks that include laborious, time consuming, subjected to intra and inter-rater variability and hindered by diversity in the appearance of tumour tissues. In this work, active contour model (ACM) was used to segment the solid enhancing subregion of the tumour. 2D brain image acquisition data using 3T MRI fast spoiled gradient echo sequence in post gadolinium of four histologically proven high-grade glioma patients were obtained. Preprocessing of the images which includes subtraction and skull stripping were performed and then followed by ACM segmentation. The results of the automatic segmentation method were compared against the manual delineation of the tumour by a trainee radiologist. Both results were further validated by an experienced neuroradiologist and a brief quantitative evaluations (pixel area and difference ratio) were performed. Preliminary results of the clinical data showed the potential of ACM model in the application of fast and large scale tumour segmentation in medical imaging.

  10. IV access in dental practice.

    LENUS (Irish Health Repository)

    Fitzpatrick, J J

    2009-04-01

    Intravenous (IV) access is a valuable skill for dental practitioners in emergency situations and in IV sedation. However, many people feel some apprehension about performing this procedure. This article explains the basic principles behind IV access, and the relevant anatomy and physiology, as well as giving a step-by-step guide to placing an IV cannula.

  11. Simplification Study of FE Model for 1000kV AC Transmission Line Insulator String Voltage and Grading Ring Surface Electric Field Distribution Calculation

    Directory of Open Access Journals (Sweden)

    Guoli Wang

    2013-09-01

    Full Text Available The finite element model of the 1000kV Ultra High Voltage (UHV AC transmission line porcelain insulator string voltage distribution and grading ring surface electric field distribution calculation has the characteristics of large size, complicated structure and various mediums. To insure the accuracy, related influencing factors should be considered to simplify the model reasonably for improving computational efficiency. A whole model and a simplified 3D finite element model of UHV AC transmission line porcelain insulator string were built. The influencing factors including tower, phase conductors, hardware fittings, yoke plate and phase interaction were considered in the analysis. And finally, the rationality of the simplified model was validated. The results comparison show that building a simplified model of three-phase bundled conductors within a certain length, simplifying the tower reasonably, omitting the hardware fittings and yoke plate and containing only single-phase insulator string model is feasible. The simplified model could replace the whole model to analyze the voltage distribution along the porcelain insulator string and the electric field distribution on the grading ring surface, and it can reduce the calculation scale, improve optimization efficiency of insulators string and grading ring parameters.

  12. The Effect of Using the Constructivist Learning Model in Teaching Science on the Achievement and Scientific Thinking of 8th Grade Students

    Science.gov (United States)

    Qarareh, Ahmed O.

    2016-01-01

    The study aims to investigate the effect of using constructivist learning model in teaching science, especially in the subject of light: its nature, mirrors, lens, and properties, on the achievement of eighth-grade students and their scientific thinking. The study sample consisted of (136) male and female 8th graders were chosen from two basic…

  13. Student-Faculty Interactions about Disappointing Grades: Application of the Goals-Plans-Actions Model and the Theory of Planned Behavior

    Science.gov (United States)

    Henningsen, Mary Lynn Miller; Valde, Kathleen S.; Russell, Gregory A.; Russell, Gregory R.

    2011-01-01

    The goals-plans-actions model and the theory of planned behavior were used to predict what lead to students having a conversation about a disappointing grade with a faculty member. Participants (N = 130) completed two surveys. In the first survey, participants completed measures of primary and secondary goals, planning, decision to engage,…

  14. Predicting Student Grade Point Average at a Community College from Scholastic Aptitude Tests and from Measures Representing Three Constructs in Vroom's Expectancy Theory Model of Motivation.

    Science.gov (United States)

    Malloch, Douglas C.; Michael, William B.

    1981-01-01

    This study was designed to determine whether an unweighted linear combination of community college students' scores on standardized achievement tests and a measure of motivational constructs derived from Vroom's expectance theory model of motivation was predictive of academic success (grade point average earned during one quarter of an academic…

  15. Student-Faculty Interactions about Disappointing Grades: Application of the Goals-Plans-Actions Model and the Theory of Planned Behavior

    Science.gov (United States)

    Henningsen, Mary Lynn Miller; Valde, Kathleen S.; Russell, Gregory A.; Russell, Gregory R.

    2011-01-01

    The goals-plans-actions model and the theory of planned behavior were used to predict what lead to students having a conversation about a disappointing grade with a faculty member. Participants (N = 130) completed two surveys. In the first survey, participants completed measures of primary and secondary goals, planning, decision to engage,…

  16. Predicting Student Grade Point Average at a Community College from Scholastic Aptitude Tests and from Measures Representing Three Constructs in Vroom's Expectancy Theory Model of Motivation.

    Science.gov (United States)

    Malloch, Douglas C.; Michael, William B.

    1981-01-01

    This study was designed to determine whether an unweighted linear combination of community college students' scores on standardized achievement tests and a measure of motivational constructs derived from Vroom's expectance theory model of motivation was predictive of academic success (grade point average earned during one quarter of an academic…

  17. Food-grade titanium dioxide exposure exacerbates tumor formation in colitis associated cancer model.

    Science.gov (United States)

    Urrutia-Ortega, Ismael M; Garduño-Balderas, Luis G; Delgado-Buenrostro, Norma L; Freyre-Fonseca, Verónica; Flores-Flores, José O; González-Robles, Arturo; Pedraza-Chaverri, José; Hernández-Pando, Rogelio; Rodríguez-Sosa, Miriam; León-Cabrera, Sonia; Terrazas, Luis I; van Loveren, Henk; Chirino, Yolanda I

    2016-07-01

    Colorectal cancer is the fourth worldwide cause of death and even if some dietary habits are consider risk factors, the contribution of food additives including foodgrade titanium dioxide (TiO2), designated as E171, has been poorly investigated. We hypothesized that oral E171 intake could have impact on the enhancement of colorectal tumor formation and we aimed to investigate if E171 administration could enhance tumor formation in a colitis associated cancer (CAC) model. BALB/c male mice were grouped as follows: a) control, b) E171, c) CAC and d) CAC + E171 group (n = 6). E171 used in this study formed agglomerates of 300 nm in water. E171 intragastric administration (5 mg/kg body weight/5 days/10 weeks) was unable to induce tumor formation but dysplastic alterations were observed in the distal colon but enhanced the tumor formation in distal colon (CAC + E171 group) measured by tumor progression markers. Some E171 particles were internalized in colonic cells of the E171 and CAC + E171 groups and both groups showed a decrease in goblet cells in the distal colon. However the CAC + E171 group showed a higher decrease of these cells that act as protection barrier in colon. These results suggest that E171 could worsen pre-existent intestinal diseases.

  18. Dibromidodimethyldipyridineplatinum(IV

    Directory of Open Access Journals (Sweden)

    Mairéad E. Kelly

    2008-11-01

    Full Text Available In the title complex, [PtBr2(CH32(C5H5N2], the PtIV metal centre lies on a twofold rotation axis and adopts a slightly distorted octahedral coordination geometry. The structure displays weak intramolecular C—H...Br hydrogen-bonding interactions.

  19. Marketing produktu Karel IV.

    OpenAIRE

    Mikšů, Šárka

    2009-01-01

    Goal of the thesis Marketing of the product Karel IV. is to propose chanels of marketing communication and indicate possibilities of next product's development. Theoretical part is based on marketing plan and it's partition. In the practical part you can find market analysis and competing products analysis, product's evolution description and marketing research.

  20. PLATO IV Accountancy Index.

    Science.gov (United States)

    Pondy, Dorothy, Comp.

    The catalog was compiled to assist instructors in planning community college and university curricula using the 48 computer-assisted accountancy lessons available on PLATO IV (Programmed Logic for Automatic Teaching Operation) for first semester accounting courses. It contains information on lesson access, lists of acceptable abbreviations for…

  1. Science-Grade Observing Systems as Process Observatories: Mapping and Understanding Nonlinearity and Multiscale Memory with Models and Observations

    Science.gov (United States)

    Barros, A. P.; Wilson, A. M.; Miller, D. K.; Tao, J.; Genereux, D. P.; Prat, O.; Petersen, W. A.; Brunsell, N. A.; Petters, M. D.; Duan, Y.

    2015-12-01

    Using the planet as a study domain and collecting observations over unprecedented ranges of spatial and temporal scales, NASA's EOS (Earth Observing System) program was an agent of transformational change in Earth Sciences over the last thirty years. The remarkable space-time organization and variability of atmospheric and terrestrial moist processes that emerged from the analysis of comprehensive satellite observations provided much impetus to expand the scope of land-atmosphere interaction studies in Hydrology and Hydrometeorology. Consequently, input and output terms in the mass and energy balance equations evolved from being treated as fluxes that can be used as boundary conditions, or forcing, to being viewed as dynamic processes of a coupled system interacting at multiple scales. Measurements of states or fluxes are most useful if together they map, reveal and/or constrain the underlying physical processes and their interactions. This can only be accomplished through an integrated observing system designed to capture the coupled physics, including nonlinear feedbacks and tipping points. Here, we first review and synthesize lessons learned from hydrometeorology studies in the Southern Appalachians and in the Southern Great Plains using both ground-based and satellite observations, physical models and data-assimilation systems. We will specifically focus on mapping and understanding nonlinearity and multiscale memory of rainfall-runoff processes in mountainous regions. It will be shown that beyond technical rigor, variety, quantity and duration of measurements, the utility of observing systems is determined by their interpretive value in the context of physical models to describe the linkages among different observations. Second, we propose a framework for designing science-grade and science-minded process-oriented integrated observing and modeling platforms for hydrometeorological studies.

  2. 7 CFR 52.1855 - Grades of Sultana raisins.

    Science.gov (United States)

    2010-01-01

    ... MARKETING ACT OF 1946 PROCESSED FRUITS AND VEGETABLES, PROCESSED PRODUCTS THEREOF, AND CERTAIN OTHER PROCESSED FOOD PRODUCTS 1 United States Standards for Grades of Processed Raisins 1 Type IV-Sultana...

  3. Method of Modeling Questions for Automated Grading of Students’ Responses in E-Learning Systems

    Directory of Open Access Journals (Sweden)

    A. A. Gurchenkov

    2015-01-01

    Full Text Available Introduction. Problem relevance. The capability to check a solution of practical problems automatically is an important functionality of any learning management system (LMS. Complex types of questions, implying creative approach to problem solving are of particular interest. There are a lot of studies presenting automated scoring algorithms of students' answers, such as mathematical expressions, graphs, molecules, etc. However, the most common types of problems in the open LMS that are being actively implemented in Russian and foreign universities (Moodle, Sakai, Ilias etc. remain simple types of questions such as, for example, multiple choice.Study subject and goal. The purpose of study is to create a method that allows integrating arbitrary algorithms of answer scoring into any existing LMS, as well as its practical implementation in the form of an independent software module, which will handle questions in LMS.Method. The model for objects of type "algorithmic question" is considered. A unified format for storing objects of this type, allowing keeping their state, is developed. The algorithm is a set of variables, which defines the responses versus input data (or vice versa. Basis variables (input are selected pseudo-randomly from a predetermined range, and based on these values resulting variables (responses are calculated. This approach allows us to synthesize variations of the same question. State of the question is saved by means of "seed" of pseudo-random number generator. A set of algorithmic problems was used to build the lifecycle management functions, namely: initialization create (, rendering render (, and evaluation answer (. These functions lay the foundation for the Application Program Interface (API and allow us to control software module responsible for the questions in LMS.Practical results. This study is completed with the implementation of software module responsible for mapping the interaction with the student and automated

  4. Comparison of the Mortality Probability Admission Model III, National Quality Forum, and Acute Physiology and Chronic Health Evaluation IV hospital mortality models: implications for national benchmarking*.

    Science.gov (United States)

    Kramer, Andrew A; Higgins, Thomas L; Zimmerman, Jack E

    2014-03-01

    To examine the accuracy of the original Mortality Probability Admission Model III, ICU Outcomes Model/National Quality Forum modification of Mortality Probability Admission Model III, and Acute Physiology and Chronic Health Evaluation IVa models for comparing observed and risk-adjusted hospital mortality predictions. Retrospective paired analyses of day 1 hospital mortality predictions using three prognostic models. Fifty-five ICUs at 38 U.S. hospitals from January 2008 to December 2012. Among 174,001 intensive care admissions, 109,926 met model inclusion criteria and 55,304 had data for mortality prediction using all three models. None. We compared patient exclusions and the discrimination, calibration, and accuracy for each model. Acute Physiology and Chronic Health Evaluation IVa excluded 10.7% of all patients, ICU Outcomes Model/National Quality Forum 20.1%, and Mortality Probability Admission Model III 24.1%. Discrimination of Acute Physiology and Chronic Health Evaluation IVa was superior with area under receiver operating curve (0.88) compared with Mortality Probability Admission Model III (0.81) and ICU Outcomes Model/National Quality Forum (0.80). Acute Physiology and Chronic Health Evaluation IVa was better calibrated (lowest Hosmer-Lemeshow statistic). The accuracy of Acute Physiology and Chronic Health Evaluation IVa was superior (adjusted Brier score = 31.0%) to that for Mortality Probability Admission Model III (16.1%) and ICU Outcomes Model/National Quality Forum (17.8%). Compared with observed mortality, Acute Physiology and Chronic Health Evaluation IVa overpredicted mortality by 1.5% and Mortality Probability Admission Model III by 3.1%; ICU Outcomes Model/National Quality Forum underpredicted mortality by 1.2%. Calibration curves showed that Acute Physiology and Chronic Health Evaluation performed well over the entire risk range, unlike the Mortality Probability Admission Model and ICU Outcomes Model/National Quality Forum models. Acute

  5. Pediatric and Adult High-Grade Glioma Stem Cell Culture Models Are Permissive to Lytic Infection with Parvovirus H-1.

    Science.gov (United States)

    Josupeit, Rafael; Bender, Sebastian; Kern, Sonja; Leuchs, Barbara; Hielscher, Thomas; Herold-Mende, Christel; Schlehofer, Jörg R; Dinsart, Christiane; Witt, Olaf; Rommelaere, Jean; Lacroix, Jeannine

    2016-05-19

    Combining virus-induced cytotoxic and immunotherapeutic effects, oncolytic virotherapy represents a promising therapeutic approach for high-grade glioma (HGG). A clinical trial has recently provided evidence for the clinical safety of the oncolytic parvovirus H-1 (H-1PV) in adult glioblastoma relapse patients. The present study assesses the efficacy of H-1PV in eliminating HGG initiating cells. H-1PV was able to enter and to transduce all HGG neurosphere culture models (n = 6), including cultures derived from adult glioblastoma, pediatric glioblastoma, and diffuse intrinsic pontine glioma. Cytotoxic effects induced by the virus have been observed in all HGG neurospheres at half maximal inhibitory concentration (IC50) doses of input virus between 1 and 10 plaque forming units per cell. H-1PV infection at this dose range was able to prevent tumorigenicity of NCH421k glioblastoma multiforme (GBM) "stem-like" cells in NOD/SCID mice. Interestingly NCH421R, an isogenic subclone with equal capacity of xenograft formation, but resistant to H-1PV infection could be isolated from the parental NCH421k culture. To reveal changes in gene expression associated with H-1PV resistance we performed a comparative gene expression analysis in these subclones. Several dysregulated genes encoding receptor proteins, endocytosis factors or regulators innate antiviral responses were identified and represent intriguing candidates for to further study molecular mechanisms of H-1PV resistance.

  6. Pediatric and Adult High-Grade Glioma Stem Cell Culture Models Are Permissive to Lytic Infection with Parvovirus H-1

    Directory of Open Access Journals (Sweden)

    Rafael Josupeit

    2016-05-01

    Full Text Available Combining virus-induced cytotoxic and immunotherapeutic effects, oncolytic virotherapy represents a promising therapeutic approach for high-grade glioma (HGG. A clinical trial has recently provided evidence for the clinical safety of the oncolytic parvovirus H-1 (H-1PV in adult glioblastoma relapse patients. The present study assesses the efficacy of H-1PV in eliminating HGG initiating cells. H-1PV was able to enter and to transduce all HGG neurosphere culture models (n = 6, including cultures derived from adult glioblastoma, pediatric glioblastoma, and diffuse intrinsic pontine glioma. Cytotoxic effects induced by the virus have been observed in all HGG neurospheres at half maximal inhibitory concentration (IC50 doses of input virus between 1 and 10 plaque forming units per cell. H-1PV infection at this dose range was able to prevent tumorigenicity of NCH421k glioblastoma multiforme (GBM “stem-like” cells in NOD/SCID mice. Interestingly NCH421R, an isogenic subclone with equal capacity of xenograft formation, but resistant to H-1PV infection could be isolated from the parental NCH421k culture. To reveal changes in gene expression associated with H-1PV resistance we performed a comparative gene expression analysis in these subclones. Several dysregulated genes encoding receptor proteins, endocytosis factors or regulators innate antiviral responses were identified and represent intriguing candidates for to further study molecular mechanisms of H-1PV resistance.

  7. Modeling the bullying prevention program design recommendations of students from grades five to eight: a discrete choice conjoint experiment.

    Science.gov (United States)

    Cunningham, Charles E; Vaillancourt, Tracy; Cunningham, Lesley J; Chen, Yvonne; Ratcliffe, Jenna

    2011-01-01

    We used a discrete choice conjoint experiment to model the bullying prevention recommendations of 845 students from grades 5 to 8 (aged 9-14). Students made choices between experimentally varied combinations of 14 four-level prevention program attributes. Latent class analysis yielded three segments. The high impact segment (27.1%) recommended uniforms, mandatory recess activities, four playground supervisors, surveillance cameras, and 4-day suspensions when students bully. The moderate impact segment (49.5%) recommended discretionary uniforms and recess activities, four playground supervisors, and 3-day suspensions. Involvement as a bully or bully-victim was associated with membership in a low impact segment (23.4%) that rejected uniforms and surveillance cameras. They recommended fewer anti-bullying activities, discretionary recess activities, fewer playground supervisors, and the 2-day suspensions. Simulations predicted most students would recommend a program maximizing student involvement combining prevention with moderate consequences. The simulated introduction of mandatory uniforms, surveillance cameras, and long suspensions reduced overall support for a comprehensive program, particularly among students involved as bullies or bully-victims.

  8. Hot-melt extruded filaments based on pharmaceutical grade polymers for 3D printing by fused deposition modeling.

    Science.gov (United States)

    Melocchi, Alice; Parietti, Federico; Maroni, Alessandra; Foppoli, Anastasia; Gazzaniga, Andrea; Zema, Lucia

    2016-07-25

    Fused deposition modeling (FDM) is a 3D printing technique based on the deposition of successive layers of thermoplastic materials following their softening/melting. Such a technique holds huge potential for the manufacturing of pharmaceutical products and is currently under extensive investigation. Challenges in this field are mainly related to the paucity of adequate filaments composed of pharmaceutical grade materials, which are needed for feeding the FDM equipment. Accordingly, a number of polymers of common use in pharmaceutical formulation were evaluated as starting materials for fabrication via hot melt extrusion of filaments suitable for FDM processes. By using a twin-screw extruder, filaments based on insoluble (ethylcellulose, Eudragit(®) RL), promptly soluble (polyethylene oxide, Kollicoat(®) IR), enteric soluble (Eudragit(®) L, hydroxypropyl methylcellulose acetate succinate) and swellable/erodible (hydrophilic cellulose derivatives, polyvinyl alcohol, Soluplus(®)) polymers were successfully produced, and the possibility of employing them for printing 600μm thick disks was demonstrated. The behavior of disks as barriers when in contact with aqueous fluids was shown consistent with the functional application of the relevant polymeric components. The produced filaments were thus considered potentially suitable for printing capsules and coating layers for immediate or modified release, and, when loaded with active ingredients, any type of dosage forms.

  9. Differentiating mass from density: The effect of modeling and student dialogue in a sixth-grade classroom

    Science.gov (United States)

    Deich, Martha L.

    The concept of density can be difficult to learn. In the middle grades, students characteristically conflate mass and density, and even after instruction many students do not distinguish them consistently (Smith, Maclin, Grosslight, & Davis, 1997). Few develop a conceptualization of density that accounts for the implications of changing mass, volume, temperature, and/or state. My work looks specifically at how students make sense of the relationship between mass and volume as they refine their understanding of density. The concept of density is challenging to teach. Traditional methods of teaching density in middle-school classrooms typically involve either the measurement of an object's mass and volume and the subsequent calculation of the ratio of the two quantities, or the observation of different materials in water to learn about their buoyancy. Unfortunately, as Carol Smith and her colleagues have documented (1985, 1992, 1997), these approaches leave many students stuck in their "commonsense frameworks" that merge mass and density into one concept. Teachers need better ways to teach density. Hence I designed an intervention to study the effects of some possibly more effective ways to teach density. I developed and taught a complex intervention (Brown, 1992) featuring student modeling, extensive student dialogue on data and data analyses, formative assessments, the substitution of hands-on inquiry for mathematical problem sets, and multiple thought experiments. The hallmarks of the intervention were modeling and student dialogue, and the research question I posed was: Does classroom practice that encourages modeling with open-ended discourse help students differentiate between the concepts of mass and density? I patterned my research on a Smith study of density instruction in eighth grade (Smith, Maclin, Grosslight, & Davis, 1997), which had a quasiexperimental research design that compared the results of teaching density differently in two classrooms. I

  10. Assessment of a model for achieving competency in administration and scoring of the WAIS-IV in post-graduate psychology students.

    Science.gov (United States)

    Roberts, Rachel M; Davis, Melissa C

    2015-01-01

    There is a need for an evidence-based approach to training professional psychologists in the administration and scoring of standardized tests such as the Wechsler Adult Intelligence Scale (WAIS) due to substantial evidence that these tasks are associated with numerous errors that have the potential to significantly impact clients' lives. Twenty three post-graduate psychology students underwent training in using the WAIS-IV according to a best-practice teaching model that involved didactic teaching, independent study of the test manual, and in-class practice with teacher supervision and feedback. Video recordings and test protocols from a role-played test administration were analyzed for errors according to a comprehensive checklist with self, peer, and faculty member reviews. 91.3% of students were rated as having demonstrated competency in administration and scoring. All students were found to make errors, with substantially more errors being detected by the faculty member than by self or peers. Across all subtests, the most frequent errors related to failure to deliver standardized instructions verbatim from the manual. The failure of peer and self-reviews to detect the majority of the errors suggests that novice feedback (self or peers) may be ineffective to eliminate errors and the use of more senior peers may be preferable. It is suggested that involving senior trainees, recent graduates and/or experienced practitioners in the training of post-graduate students may have benefits for both parties, promoting a peer-learning and continuous professional development approach to the development and maintenance of skills in psychological assessment.

  11. Electronic structure description of a [Co(III)3Co(IV)O4] cluster: a model for the paramagnetic intermediate in cobalt-catalyzed water oxidation.

    Science.gov (United States)

    McAlpin, J Gregory; Stich, Troy A; Ohlin, C André; Surendranath, Yogesh; Nocera, Daniel G; Casey, William H; Britt, R David

    2011-10-01

    Multifrequency electron paramagnetic resonace (EPR) spectroscopy and electronic structure calculations were performed on [Co(4)O(4)(C(5)H(5)N)(4)(CH(3)CO(2))(4)](+) (1(+)), a cobalt tetramer with total electron spin S = 1/2 and formal cobalt oxidation states III, III, III, and IV. The cuboidal arrangement of its cobalt and oxygen atoms is similar to that of proposed structures for the molecular cobaltate clusters of the cobalt-phosphate (Co-Pi) water-oxidizing catalyst. The Davies electron-nuclear double resonance (ENDOR) spectrum is well-modeled using a single class of hyperfine-coupled (59)Co nuclei with a modestly strong interaction (principal elements of the hyperfine tensor are equal to [-20(±2), 77(±1), -5(±15)] MHz). Mims (1)H ENDOR spectra of 1(+) with selectively deuterated pyridine ligands confirm that the amount of unpaired spin on the cobalt-bonding partner is significantly reduced from unity. Multifrequency (14)N ESEEM spectra (acquired at 9.5 and 34.0 GHz) indicate that four nearly equivalent nitrogen nuclei are coupled to the electron spin. Cumulatively, our EPR spectroscopic findings indicate that the unpaired spin is delocalized almost equally across the eight core atoms, a finding corroborated by results from DFT calculations. Each octahedrally coordinated cobalt ion is forced into a low-spin electron configuration by the anionic oxo and carboxylato ligands, and a fractional electron hole is localized on each metal center in a Co 3d(xz,yz)-based molecular orbital for this essentially [Co(+3.125)(4)O(4)] system. Comparing the EPR spectrum of 1(+) with that of the catalyst film allows us to draw conclusions about the electronic structure of this water-oxidation catalyst.

  12. [The relationships of intelligence and memory assessed using the WAIS-IV and the WMS-IV].

    Science.gov (United States)

    Lepach, A C; Daseking, M; Petermann, F; Waldmann, H C

    2013-11-01

    This study examines the relationships of intelligence and memory scores derived from WAIS-IV and WMS-IV. We were especially interested in the reciprocal predictive values of the test scales. A sample of 137 healthy adults with an age range between 16 and 69 years was assessed with the WAIS-IV and the WMS-IV. The test order was balanced. Pearson correlations were conducted on the subtest and scale level. A series of 14 linear regression models was tested with memory performance as predictor for intelligence and vice versa. A model including the 3 main memory scales of the WMS-IV was able to predict the global IQ best. It nevertheless explained only 46% of the variance. The memory and intelligence measures show significant relationships, but also represent distinct functions. WAIS-IV and WMS-IV complement one another. © Georg Thieme Verlag KG Stuttgart · New York.

  13. Validity of DSM-IV attention deficit/hyperactivity disorder symptom dimensions and subtypes.

    Science.gov (United States)

    Willcutt, Erik G; Nigg, Joel T; Pennington, Bruce F; Solanto, Mary V; Rohde, Luis A; Tannock, Rosemary; Loo, Sandra K; Carlson, Caryn L; McBurnett, Keith; Lahey, Benjamin B

    2012-11-01

    Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (DSM-IV) criteria for attention deficit/hyperactivity disorder (ADHD) specify two dimensions of inattention and hyperactivity-impulsivity symptoms that are used to define three nominal subtypes: predominantly hyperactive-impulsive type (ADHD-H), predominantly inattentive type (ADHD-I), and combined type (ADHD-C). To aid decision making for DSM-5 and other future diagnostic systems, a comprehensive literature review and meta-analysis of 546 studies was completed to evaluate the validity of the DSM-IV model of ADHD. Results indicated that DSM-IV criteria identify individuals with significant and persistent impairment in social, academic, occupational, and adaptive functioning when intelligence, demographic factors, and concurrent psychopathology are controlled. Available data overwhelmingly support the concurrent, predictive, and discriminant validity of the distinction between inattention and hyperactivity-impulsivity symptoms, and indicate that nearly all differences among the nominal subtypes are consistent with the relative levels of inattention and hyperactivity-impulsivity symptoms that define the subtypes. In contrast, the DSM-IV subtype model is compromised by weak evidence for the validity of ADHD-H after first grade, minimal support for the distinction between ADHD-I and ADHD-C in studies of etiological influences, academic and cognitive functioning, and treatment response, and the marked longitudinal instability of all three subtypes. Overall, we conclude that the DSM-IV ADHD subtypes provide a convenient clinical shorthand to describe the functional and behavioral correlates of current levels of inattention and hyperactivity-impulsivity symptoms, but do not identify discrete subgroups with sufficient long-term stability to justify the classification of distinct forms of the disorder. Empirical support is stronger for an alternative model that would replace the subtypes with dimensional

  14. Validity of DSM-IV attention–deficit/hyperactivity disorder symptom dimensions and subtypes

    Science.gov (United States)

    Willcutt, Erik G.; Nigg, Joel T.; Pennington, Bruce F.; Solanto, Mary V.; Rohde, Luis A.; Tannock, Rosemary; Loo, Sandra K.; Carlson, Caryn L.; McBurnett, Keith; Lahey, Benjamin B.

    2013-01-01

    DSM-IV criteria for ADHD specify two dimensions of inattention and hyperactivity-impulsivity symptoms that are used to define three nominal subtypes: predominantly hyperactive-impulsive type (ADHD-H), predominantly inattentive type (ADHD-I), and combined type (ADHD-C). To aid decision-making for DSM-5 and other future diagnostic systems, a comprehensive literature review and meta-analysis of 546 studies was completed to evaluate the validity of the DSM-IV model of ADHD. Results indicated that DSM-IV criteria identify individuals with significant and persistent impairment in social, academic, occupational, and adaptive functioning when intelligence, demographic factors, and concurrent psychopathology are controlled. Available data overwhelmingly support the concurrent, predictive, and discriminant validity of the distinction between inattention and hyperactivity-impulsivity symptoms, and indicate that nearly all differences among the nominal subtypes are consistent with the relative levels of inattention and hyperactivity-impulsivity symptoms that define the subtypes. In contrast, the validity of the DSM-IV subtype model is compromised by weak evidence for the validity of ADHD-H after first grade, minimal support for the distinction between ADHD-I and ADHD-C in studies of etiological influences, academic and cognitive functioning, and treatment response, and the marked longitudinal instability of all three subtypes. Overall, it is concluded that the DSM-IV ADHD subtypes provide a convenient clinical shorthand to describe the functional and behavioral correlates of current levels of inattention and hyperactivity-impulsivity symptoms, but do not identify discrete subgroups with sufficient long-term stability to justify the classification of distinct forms of the disorder. Empirical support is stronger for an alternative model that would replace the subtypes with dimensional modifiers that reflect the number of inattention and hyperactivity-impulsivity symptoms at the

  15. Enhanced Design Alternative IV

    Energy Technology Data Exchange (ETDEWEB)

    N. E. Kramer

    1999-05-18

    This report evaluates Enhanced Design Alternative (EDA) IV as part of the second phase of the License Application Design Selection (LADS) effort. The EDA IV concept was compared to the VA reference design using criteria from the ''Design Input Request for LADS Phase II EDA Evaluations'' (CRWMS M&O 1999b) and (CRWMS M&O 1999f). Briefly, the EDA IV concept arranges the waste packages close together in an emplacement configuration known as ''line load''. Continuous pre-closure ventilation keeps the waste packages from exceeding the 350 C cladding and 200 C (4.3.13) drift wall temperature limits. This EDA concept keeps relatively high, uniform emplacement drift temperatures (post-closure) to drive water away from the repository and thus dry out the pillars between emplacement drifts. The waste package is shielded to permit human access to emplacement drifts and includes an integral filler inside the package to reduce the amount of water that can contact the waste form. Closure of the repository is desired 50 years after first waste is emplaced. Both backfill and a drip shields will be emplaced at closure to improve post-closure performance.

  16. Grading for Understanding - Standards-Based Grading

    Science.gov (United States)

    Zimmerman, Todd

    2017-01-01

    Standards-based grading (SBG), sometimes called learning objectives-based assessment (LOBA), is an assessment model that relies on students demonstrating mastery of learning objectives (sometimes referred to as standards). The goal of this grading system is to focus students on mastering learning objectives rather than on accumulating points. I have used SBG in an introductory physics course for the past five years and worked with several physics faculty members to implement SBG in the first and second semester of algebra-based and calculus-based introductory physics courses at a primarily undergraduate comprehensive public university with class sizes of 48 students. In this article I will discuss methods for implementing SBG in a physics class.

  17. Elucidating PID Degradation Mechanisms and In Situ Dark I-V Monitoring for Modeling Degradation Rate in CdTe Thin-Film Modules

    DEFF Research Database (Denmark)

    Hacke, Peter; Spataru, Sergiu; Johnston, Steve

    2016-01-01

    A progression of potential-induced degradation (PID) mechanisms are observed in CdTe modules, including shunting/junction degradation and two different manifestations of series resistance depending on the stress level and water ingress. The dark I-V method for in-situ characterization of Pmax based...

  18. Micro-mechanical modelling of ductile failure in 6005A aluminium using a physics based strain hardening larw including stage IV

    DEFF Research Database (Denmark)

    Simar, Aude; Nielsen, Kim Lau; de Meester, Bruno

    2010-01-01

    The strain hardening and damage behaviour of isothermally heat treated 6005A aluminium is investigated in order to link the thermal treatment conditions, microstructure and fracture strain. The need for a plastic flow rule involving a stage IV hardening at large strain was found essential...

  19. Grade Inflation in Higher Education.

    Science.gov (United States)

    Ediger, Marlow

    The topic of grade inflation, the awarding of too many "A's" and "B's", is frequently mentioned in the literature on higher education. Many educational philosophies have suggested ways to evaluate students fairly. Some professors have used the bell-shaped curve as a model, giving grades according to the normal distribution curve regardless of the…

  20. On the use of speciation techniques and ab initio modelling to understand tetravalent actinide behavior in a biological medium: An(IV)DTPA case.

    Science.gov (United States)

    Aupiais, J; Bonin, L; Den Auwer, C; Moisy, P; Siberchicot, B; Topin, S

    2016-03-07

    In the case of an accidental nuclear event, contamination of human bodies by actinide elements may occur. Such elements have the particularity to exhibit both radiological and chemical toxicities that may induce severe damages at several levels, depending on the biokinetics of the element. In order to eliminate the actinide elements before they are stored in target organs (liver, kidneys, or bone, depending on the element), sequestering agents must be quickly injected. However, to date, there is still no ideal sequestering agent, despite the recent interest in this topic due to contamination concerns. DTPA (diethylene triamine pentaacetic acid) is currently generating interest for the development of oral or alternative self-administrable forms. Although biokinetics data are mostly available, molecular scale characterization of actinide-DTPA complexes is still scarce. Nevertheless, strong interest is growing in the characterization of An(IV)DTPA(-) complexes at the molecular level because this opens the way for predicting the stability constants of unknown systems or even for developing new analytical strategies aimed at better and more selective decorporation. For this purpose, Extended X-ray Absorption Fine Structure (EXAFS) and Ab Initio Molecular Dynamics (AIMD) investigations were undertaken and compared with capillary electrophoresis (CE) used in a very unusual way. Indeed, it is commonly believed that CE is incapable of extracting structural information. In capillary electrophoresis, the electrophoretic mobility of an ion is a function of its charge and size. Despite very similar ratios, partial separations between An(IV)DTPA(-) species (An(IV) = Th, U, Np, Pu) were obtained. A linear relationship between the electrophoretic mobility and the actinide--oxygen distance calculated by AIMD was evidenced. As an example, the interpolated U-O distances in U(IV)DTPA(-) from CE-ICPMS experiments, EXAFS, AIMD, and the relationship between the stability constants and

  1. Quality-Related Monitoring and Grading of Granulated Products by Weibull-Distribution Modeling of Visual Images with Semi-Supervised Learning

    Directory of Open Access Journals (Sweden)

    Jinping Liu

    2016-06-01

    Full Text Available The topic of online product quality inspection (OPQI with smart visual sensors is attracting increasing interest in both the academic and industrial communities on account of the natural connection between the visual appearance of products with their underlying qualities. Visual images captured from granulated products (GPs, e.g., cereal products, fabric textiles, are comprised of a large number of independent particles or stochastically stacking locally homogeneous fragments, whose analysis and understanding remains challenging. A method of image statistical modeling-based OPQI for GP quality grading and monitoring by a Weibull distribution(WD model with a semi-supervised learning classifier is presented. WD-model parameters (WD-MPs of GP images’ spatial structures, obtained with omnidirectional Gaussian derivative filtering (OGDF, which were demonstrated theoretically to obey a specific WD model of integral form, were extracted as the visual features. Then, a co-training-style semi-supervised classifier algorithm, named COSC-Boosting, was exploited for semi-supervised GP quality grading, by integrating two independent classifiers with complementary nature in the face of scarce labeled samples. Effectiveness of the proposed OPQI method was verified and compared in the field of automated rice quality grading with commonly-used methods and showed superior performance, which lays a foundation for the quality control of GP on assembly lines.

  2. Quality-Related Monitoring and Grading of Granulated Products by Weibull-Distribution Modeling of Visual Images with Semi-Supervised Learning

    Science.gov (United States)

    Liu, Jinping; Tang, Zhaohui; Xu, Pengfei; Liu, Wenzhong; Zhang, Jin; Zhu, Jianyong

    2016-01-01

    The topic of online product quality inspection (OPQI) with smart visual sensors is attracting increasing interest in both the academic and industrial communities on account of the natural connection between the visual appearance of products with their underlying qualities. Visual images captured from granulated products (GPs), e.g., cereal products, fabric textiles, are comprised of a large number of independent particles or stochastically stacking locally homogeneous fragments, whose analysis and understanding remains challenging. A method of image statistical modeling-based OPQI for GP quality grading and monitoring by a Weibull distribution(WD) model with a semi-supervised learning classifier is presented. WD-model parameters (WD-MPs) of GP images’ spatial structures, obtained with omnidirectional Gaussian derivative filtering (OGDF), which were demonstrated theoretically to obey a specific WD model of integral form, were extracted as the visual features. Then, a co-training-style semi-supervised classifier algorithm, named COSC-Boosting, was exploited for semi-supervised GP quality grading, by integrating two independent classifiers with complementary nature in the face of scarce labeled samples. Effectiveness of the proposed OPQI method was verified and compared in the field of automated rice quality grading with commonly-used methods and showed superior performance, which lays a foundation for the quality control of GP on assembly lines. PMID:27367703

  3. Dynamics of Circulating γδ T Cell Activity in an Immunocompetent Mouse Model of High-Grade Glioma.

    Directory of Open Access Journals (Sweden)

    Benjamin H Beck

    Full Text Available Human γδ T cells are potent effectors against glioma cell lines in vitro and in human/mouse xenograft models of glioblastoma, however, this effect has not been investigated in an immunocompetent mouse model. In this report, we established GL261 intracranial gliomas in syngeneic WT C57BL/6 mice and measured circulating γδ T cell count, phenotype, Vγ/Vδ repertoire, tumor histopathology, NKG2D ligands expression, and T cell invasion at day 10-12 post-injection and at end stage. Circulating γδ T cells transiently increased and upregulated Annexin V expression at post-tumor day 10-12 followed by a dramatic decline in γδ T cell count at end stage. T cell receptor repertoire showed no changes in Vγ1, Vγ4, Vγ7 or Vδ1 subsets from controls at post-tumor day 10-12 or at end stage except for an end-stage increase in the Vδ4 population. Approximately 12% of γδ T cells produced IFN-γ. IL-17 and IL-4 producing γδ T cells were not detected. Tumor progression was the same in TCRδ-/- C57BL/6 mice as that observed in WT mice, suggesting that γδ T cells exerted neither a regulatory nor a sustainable cytotoxic effect on the tumor. WT mice that received an intracranial injection of γδ T cells 15m following tumor placement showed evidence of local tumor growth inhibition but this was insufficient to confer a survival advantage over untreated controls. Taken together, our findings suggest that an early nonspecific proliferation of γδ T cells followed by their depletion occurs in mice implanted with syngeneic GL261 gliomas. The mechanism by which γδ T cell expansion occurs remains a subject for further investigation of the mechanisms responsible for this immune response in the setting of high-grade glioma.

  4. Survival analysis of patients with high-grade gliomas based on data mining of imaging variables.

    Science.gov (United States)

    Zacharaki, E I; Morita, N; Bhatt, P; O'Rourke, D M; Melhem, E R; Davatzikos, C

    2012-06-01

    The prediction of prognosis in HGGs is poor in the majority of patients. Our aim was to test whether multivariate prediction models constructed by machine-learning methods provide a more accurate predictor of prognosis in HGGs than histopathologic classification. The prediction of survival was based on DTI and rCBV measurements as an adjunct to conventional imaging. The relationship of survival to 55 variables, including clinical parameters (age, sex), categoric or continuous tumor descriptors (eg, tumor location, extent of resection, multifocality, edema), and imaging characteristics in ROIs, was analyzed in a multivariate fashion by using data-mining techniques. A variable selection method was applied to identify the overall most important variables. The analysis was performed on 74 HGGs (18 anaplastic gliomas WHO grades III/IV and 56 GBMs or gliosarcomas WHO grades IV/IV). Five variables were identified as the most significant, including the extent of resection, mass effect, volume of enhancing tumor, maximum B0 intensity, and mean trace intensity in the nonenhancing/edematous region. These variables were used to construct a prediction model based on a J48 classification tree. The average classification accuracy, assessed by cross-validation, was 85.1%. Kaplan-Meier survival curves showed that the constructed prediction model classified malignant gliomas in a manner that better correlates with clinical outcome than standard histopathology. Prediction models based on data-mining algorithms can provide a more accurate predictor of prognosis in malignant gliomas than histopathologic classification alone.

  5. Graded tunnelling barrier and oxygen concentration in thermally grown ultrathin SiO{sub x} gate oxide

    Energy Technology Data Exchange (ETDEWEB)

    Gitlin, Daniel [Device Physics Laboratory, Xilinx, Inc., 2100 Logic Drive, San Jose, CA 95124-3400 (United States); Karp, James [Device Physics Laboratory, Xilinx, Inc., 2100 Logic Drive, San Jose, CA 95124-3400 (United States); Moyzhes, Boris [Geballe Laboratory for Advanced Materials, McCullough Building, Stanford University, CA 94305-4045 (United States)

    2007-04-07

    Barrier parameters of a thermally grown SiO{sub x} gate oxide are derived by relating the SIMS oxygen concentration profile to the barrier height. Even in the simple analytical form such a graded barrier model agrees with the tunnelling current and its voltage dependence in both directions. Asymmetrical tunnelling I-Vs in the symmetrical n{sup +}Si-SiO{sub x}-n{sup +}Si structure are due to both graded barrier and penetration of carriers into the gate oxide at the SiO{sub x}-Si substrate interface.

  6. Improving Grading Consistency through Grade Lift Reporting

    Science.gov (United States)

    Millet, Ido

    2010-01-01

    We define Grade Lift as the difference between average class grade and average cumulative class GPA. This metric provides an assessment of how lenient the grading was for a given course. In 2006, we started providing faculty members individualized Grade Lift reports reflecting their position relative to an anonymously plotted school-wide…

  7. Gas Metal Arc Welding Process Modeling and Prediction of Weld Microstructure in MIL A46100 Armor-Grade Martensitic Steel

    Science.gov (United States)

    2013-06-01

    bainitic , martensitic) phase trans- formations and the diffusional phase-transformations which produce microstructural constituents (e.g., pearlite...single-phase austenite region); (ii) the fine-grained sub-zone, which contains martensite and bainite formed during cooling from austenite with a...exposed and the products of austenite decompositionduringcooling (i.e.,martensite, bainite , ferrite); and (iv) the so-called sub-critical zone, within

  8. Strategy-focused writing instruction: just observing and reflecting on a model benefits 6th grade students

    NARCIS (Netherlands)

    Fidalgo, R.; Torrance, M.; Rijlaarsdam, G.C.W.; van den Bergh, Huub; M.L., Álvarez,

    2015-01-01

    Three groups of typically-developing 6th grade students (total N = 62) each completed strategy-focused writing training. Using a combined lagged-group and cross-panel design we assessed the effectiveness of a sequence of four different instructional components: observation and group reflection on a

  9. Experimental Results that Question the Ramirez-Castaneda Model for Teaching Reading to First Grade Mexican Americans.

    Science.gov (United States)

    Cohen, S. Alan; Rodriquez, Samuel

    1980-01-01

    Results of a study conducted with first-grade Mexican American children indicate that direct reading instruction to precise behavioral objectives is more effective than teaching to Mexican American children's supposed "cultural learning styles" as recommended by Manuel Ramirez and Alfredo Castaneda in 1974. (GT)

  10. Experimental Results that Question the Ramirez-Castaneda Model for Teaching Reading to First Grade Mexican Americans.

    Science.gov (United States)

    Cohen, S. Alan; Rodriquez, Samuel

    1980-01-01

    Results of a study conducted with first-grade Mexican American children indicate that direct reading instruction to precise behavioral objectives is more effective than teaching to Mexican American children's supposed "cultural learning styles" as recommended by Manuel Ramirez and Alfredo Castaneda in 1974. (GT)

  11. Studying platinum sensitivity and resistance in high-grade serous ovarian cancer : Different models for different questions

    NARCIS (Netherlands)

    Alkema, Nicolette G.; Wisman, G. Bea A.; van der Zee, Ate G. J.; van Vugt, Marcel A. T. M.; de Jong, Steven

    High-grade serous ovarian cancer (HGSOC) has the highest mortality rate among all gynecological cancers. Patients are generally diagnosed in an advanced stage with the majority of cases displaying platinum resistant relapses. Recent genomic interrogation of large numbers of HGSOC patient samples

  12. A Model for Increasing Reform Implementation and Teacher Efficacy: Teacher Peer Coaching in Grades 3 and 6 Mathematics

    Science.gov (United States)

    Bruce, Catherine D.; Ross, John A.

    2008-01-01

    This study examined the effects of peer coaching on mathematics teaching practices and teacher beliefs about their capacity to have an impact on student learning. Twelve teachers in grades 3 and 6 participated in a brief but intensive professional development program over six months. The program focused on effective mathematics teaching strategies…

  13. Modelling TIMSS data in an European comparative perspective: exploring influencing factors on achievement in mathematics grade 8

    NARCIS (Netherlands)

    Bos, Klaas; Kuiper, Wilmad

    1999-01-01

    In international comparative studies like TIMSS data analysis is aimed at differences and similarities among education systems (countries). In this article the outcomes are presented of explorative path analysis on data collected with grade 8 students and classrooms in eight Western and two Central

  14. Optimizing a machine learning based glioma grading system using multi-parametric MRI histogram and texture features.

    Science.gov (United States)

    Zhang, Xin; Yan, Lin-Feng; Hu, Yu-Chuan; Li, Gang; Yang, Yang; Han, Yu; Sun, Ying-Zhi; Liu, Zhi-Cheng; Tian, Qiang; Han, Zi-Yang; Liu, Le-De; Hu, Bin-Quan; Qiu, Zi-Yu; Wang, Wen; Cui, Guang-Bin

    2017-07-18

    Current machine learning techniques provide the opportunity to develop noninvasive and automated glioma grading tools, by utilizing quantitative parameters derived from multi-modal magnetic resonance imaging (MRI) data. However, the efficacies of different machine learning methods in glioma grading have not been investigated.A comprehensive comparison of varied machine learning methods in differentiating low-grade gliomas (LGGs) and high-grade gliomas (HGGs) as well as WHO grade II, III and IV gliomas based on multi-parametric MRI images was proposed in the current study. The parametric histogram and image texture attributes of 120 glioma patients were extracted from the perfusion, diffusion and permeability parametric maps of preoperative MRI. Then, 25 commonly used machine learning classifiers combined with 8 independent attribute selection methods were applied and evaluated using leave-one-out cross validation (LOOCV) strategy. Besides, the influences of parameter selection on the classifying performances were investigated. We found that support vector machine (SVM) exhibited superior performance to other classifiers. By combining all tumor attributes with synthetic minority over-sampling technique (SMOTE), the highest classifying accuracy of 0.945 or 0.961 for LGG and HGG or grade II, III and IV gliomas was achieved. Application of Recursive Feature Elimination (RFE) attribute selection strategy further improved the classifying accuracies. Besides, the performances of LibSVM, SMO, IBk classifiers were influenced by some key parameters such as kernel type, c, gama, K, etc. SVM is a promising tool in developing automated preoperative glioma grading system, especially when being combined with RFE strategy. Model parameters should be considered in glioma grading model optimization.

  15. Effects of an Inverted Instructional Delivery Model on Achievement of Ninth-Grade Physical Science Honors Students

    Science.gov (United States)

    Howell, Donna

    This mixed-methods action research study was designed to assess the achievement of ninth-grade Physical Science Honors students by analysis of pre and posttest data. In addition, perceptual data from students, parents, and the researcher were collected to form a complete picture of the flipped lecture format versus the traditional lecture format. The researcher utilized a 4MAT learning cycle in two Physical Science Honors classes. One of these classes was traditionally delivered with lecture-type activities taking place inside the classroom and homework-type activities taking place at home; the other inverted, or flipped, delivered with lecture-type activities taking place outside the classroom and homework-type activities taking place inside the classroom. Existing unit pre and posttests for both classes were analyzed for differences in academic achievement. At the completion of the units, the flipped class students and parents were surveyed, and student focus groups were convened to ascertain their perceptions of the flipped classroom delivery model. Statistical analysis of posttest data revealed that there is no significant difference between the traditional lecture delivery format and the flipped delivery format. Analysis of perceptual data revealed six themes that must be considered when deciding to flip the classroom: how to hold students accountable for viewing the at-home videos, accessibility of students to the required technology, technical considerations relating to the video production, comprehension of the material both during and after viewing the videos, pedagogy of the overall flipped method, and preference for the flipped method overall. Findings revealed that students, parents, and the researcher all had a preference for the flipped class format, provided the above issues are addressed. The flipped class format encourages students to become more responsible for their learning, and, in addition, students reported that the hands-on inquiry

  16. Model of automatic fuel management for the Atucha II nuclear central with the PUMA IV code; Modelo de gestion automatica de combustible para la Central Nuclear Atucha II con el codigo PUMA IV

    Energy Technology Data Exchange (ETDEWEB)

    Marconi G, J.F.; Tarazaga, A.E.; Romero, L.D. [CNEA, Av. Gral. Paz 1499 San Martin-Bs. As. (Argentina)]. e-mail: marconi@cnea.gov.ar

    2007-07-01

    The Atucha II central is a heavy water power station and natural uranium. For this reason and due to the first floor reactivity excess that have this type of reactors, it is necessary to carry out a continuous fuel management and with the central in power (for the case of Atucha II every 0.7 days approximately). To maintain in operation these centrals and to achieve a good fuels economy, different types of negotiate of fuels that include areas and roads where the fuels displace inside the core are proved; it is necessary to prove the great majority of these managements in long periods in order to corroborate the behavior of the power station and the burnt of extraction of the fuel elements. To carry out this work it is of great help that a program implements the approaches to continue in each replacement, using the roads and areas of each administration type to prove, and this way to obtain as results the one regulations execution in the time and the average burnt of extraction of the fuel elements, being fundamental this last data for the operator company of the power station. To carry out the previous work it is necessary that a physicist with experience in fuel management proves each one of the possible managements, even those that quickly can be discarded if its don't fulfill with the regulatory standards or its possess an average extraction burnt too much low. For this it is of fundamental help that with an automatic model the different administrations are proven and lastly the physicist analyzes the more important cases. The pattern in question not only allows to program different types of roads and areas of fuel management, but rather it also foresees the possibility to disable some of the approaches. (Author)

  17. Examining Computational Assumptions For Godiva IV

    Energy Technology Data Exchange (ETDEWEB)

    Kirkland, Alexander Matthew [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Jaegers, Peter James [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-08-11

    Over the course of summer 2016, the effects of several computational modeling assumptions with respect to the Godiva IV reactor were examined. The majority of these assumptions pertained to modeling errors existing in the control rods and burst rod. The Monte Carlo neutron transport code, MCNP, was used to investigate these modeling changes, primarily by comparing them to that of the original input deck specifications.

  18. Diaquatetrabromidotin(IV trihydrate

    Directory of Open Access Journals (Sweden)

    Fei Ye

    2012-09-01

    Full Text Available The title compound, [SnBr4(H2O2]·3H2O, forms large colourless crystals in originally sealed samples of tin tetrabromide. It constitutes the first structurally characterized hydrate of SnBr4 and is isostructural with the corresponding hydrate of SnCl4. It is composed of SnIV atoms octahedrally coordinated by four Br atoms and two cis-related water molecules. The octahedra exhibit site symmetry 2. They are arranged into columns along [001] via medium–strong O—H...O hydrogen bonds involving the two lattice water molecules (one situated on a twofold rotation axis while the chains are interconnected via longer O—H...Br hydrogen bonds, forming a three-dimensional network.

  19. Exploring the Origin of Differential Binding Affinities of Human Tubulin Isotypes αβII, αβIII and αβIV for DAMA-Colchicine Using Homology Modelling, Molecular Docking and Molecular Dynamics Simulations.

    Science.gov (United States)

    Kumbhar, Bajarang Vasant; Borogaon, Anubhaw; Panda, Dulal; Kunwar, Ambarish

    2016-01-01

    Tubulin isotypes are found to play an important role in regulating microtubule dynamics. The isotype composition is also thought to contribute in the development of drug resistance as tubulin isotypes show differential binding affinities for various anti-cancer agents. Tubulin isotypes αβII, αβIII and αβIV show differential binding affinity for colchicine. However, the origin of differential binding affinity is not well understood at the molecular level. Here, we investigate the origin of differential binding affinity of a colchicine analogue N-deacetyl-N-(2-mercaptoacetyl)-colchicine (DAMA-colchicine) for human αβII, αβIII and αβIV isotypes, employing sequence analysis, homology modeling, molecular docking, molecular dynamics simulation and MM-GBSA binding free energy calculations. The sequence analysis study shows that the residue compositions are different in the colchicine binding pocket of αβII and αβIII, whereas no such difference is present in αβIV tubulin isotypes. Further, the molecular docking and molecular dynamics simulations results show that residue differences present at the colchicine binding pocket weaken the bonding interactions and the correct binding of DAMA-colchicine at the interface of αβII and αβIII tubulin isotypes. Post molecular dynamics simulation analysis suggests that these residue variations affect the structure and dynamics of αβII and αβIII tubulin isotypes, which in turn affect the binding of DAMA-colchicine. Further, the binding free-energy calculation shows that αβIV tubulin isotype has the highest binding free-energy and αβIII has the lowest binding free-energy for DAMA-colchicine. The order of binding free-energy for DAMA-colchicine is αβIV ≃ αβII > αβIII. Thus, our computational approaches provide an insight into the effect of residue variations on differential binding of αβII, αβIII and αβIV tubulin isotypes with DAMA-colchicine and may help to design new analogues with higher

  20. Exploring the Origin of Differential Binding Affinities of Human Tubulin Isotypes αβII, αβIII and αβIV for DAMA-Colchicine Using Homology Modelling, Molecular Docking and Molecular Dynamics Simulations.

    Directory of Open Access Journals (Sweden)

    Bajarang Vasant Kumbhar

    Full Text Available Tubulin isotypes are found to play an important role in regulating microtubule dynamics. The isotype composition is also thought to contribute in the development of drug resistance as tubulin isotypes show differential binding affinities for various anti-cancer agents. Tubulin isotypes αβII, αβIII and αβIV show differential binding affinity for colchicine. However, the origin of differential binding affinity is not well understood at the molecular level. Here, we investigate the origin of differential binding affinity of a colchicine analogue N-deacetyl-N-(2-mercaptoacetyl-colchicine (DAMA-colchicine for human αβII, αβIII and αβIV isotypes, employing sequence analysis, homology modeling, molecular docking, molecular dynamics simulation and MM-GBSA binding free energy calculations. The sequence analysis study shows that the residue compositions are different in the colchicine binding pocket of αβII and αβIII, whereas no such difference is present in αβIV tubulin isotypes. Further, the molecular docking and molecular dynamics simulations results show that residue differences present at the colchicine binding pocket weaken the bonding interactions and the correct binding of DAMA-colchicine at the interface of αβII and αβIII tubulin isotypes. Post molecular dynamics simulation analysis suggests that these residue variations affect the structure and dynamics of αβII and αβIII tubulin isotypes, which in turn affect the binding of DAMA-colchicine. Further, the binding free-energy calculation shows that αβIV tubulin isotype has the highest binding free-energy and αβIII has the lowest binding free-energy for DAMA-colchicine. The order of binding free-energy for DAMA-colchicine is αβIV ≃ αβII >> αβIII. Thus, our computational approaches provide an insight into the effect of residue variations on differential binding of αβII, αβIII and αβIV tubulin isotypes with DAMA-colchicine and may help to design new

  1. A Flow Model of the U.S. Army Field Grade Officer Corps to Produce the Five Year Promotion Plan

    Science.gov (United States)

    1985-09-01

    vacancies at all grades. This has 17 been shown to be important so that ambitious young officers have a secure career expectation . The term used by the...and sometimes had a significant impact on career expectation . In order to reduce the complexity of this cumbersome system, DOPMA provides for a single...the intermediate ranks as character- ized by extremely long promotion list durations. The concern is that this may have an adverse impact on the career

  2. A Psychological Model of Translation Quality Assessment: Applying Bloom’s Taxonomy of Educational Objectives to Grade English Texts

    Directory of Open Access Journals (Sweden)

    Natasha Pourdana

    2014-03-01

    Full Text Available The present study explored the possibility of grading English texts based on the psychological processes a non-native English translator might go through by applying Benjamin Bloom’s Taxonomy of Educational Objectives: Cognitive Domain. The researchers’ primary assumption was that the difficulty of English texts would increase as the translator’s performance proceeds from translating an English text that requires their only language Knowledge through the texts requiring increasing demands of their Comprehension, Application, Analysis, Aynthesis and Evaluation abilities. To the researchers, the quality of the translation performance could be assessed based on the type of psychological processing they conduct in translating a given text. To fulfil the ultimate purpose of the research, 30 undergraduate students majoring in English translation at Islamic Azad University, Karaj Branch, Iran took part in this investigation in 2012. In addition to Comprehensive English Language Test (CELT, the participants were given a translation essay-type test that included six short English passages of 150 to 200 words. The texts were carefully graded based on the type of behavioural objectives (i.e., psychological processes demanded of the translator and listed according to the hierarchy of Bloom’s cognitive domain. A non-parametric test of Kruskal Wallis proved that except for the fifth level, the Synthesis text, the trainee translators’ quality of performance was graded properly based on the difficulty levels expected and explored in Bloom’s levels of cognitive domain. The findings in this study are considerately practical in translation quality assessment, upgrading the reliability estimate of translation tests and teaching translation skills and strategies. Keywords: EFL, Bloom’s Cognitive Domain, Grading, Psychological Processing, Translation Quality Assessment

  3. A Psychological Model of Translation Quality Assessment: Applying Bloom’s Taxonomy of Educational Objectives to Grade English Texts

    OpenAIRE

    Natasha Pourdana; John S. Rajeski

    2014-01-01

    The present study explored the possibility of grading English texts based on the psychological processes a non-native English translator might go through by applying Benjamin Bloom’s Taxonomy of Educational Objectives: Cognitive Domain. The researchers’ primary assumption was that the difficulty of English texts would increase as the translator’s performance proceeds from translating an English text that requires their only language Knowledge through the texts requiring increasing demands of ...

  4. Education for Self-Responsibility IV: Nutrition Education Curriculum Guide. Grade 9-Grade 12.

    Science.gov (United States)

    Texas Tech Univ., Lubbock. Home Economics Curriculum Center.

    This is the third part of a three-part curriculum guide dedicated to improving the nutritional status of children and adolescents as well as inspiring lifetime habits of healthy eating. It is also a total nutrition education program that encompasses nutritional aspects of a student's daily life both at school and at home. Teachers are provided…

  5. dBASE IV basics

    Energy Technology Data Exchange (ETDEWEB)

    O`Connor, P.

    1994-09-01

    This is a user`s manual for dBASE IV. dBASE IV is a popular software application that can be used on your personal computer to help organize and maintain your database files. It is actually a set of tools with which you can create, organize, select and manipulate data in a simple yet effective manner. dBASE IV offers three methods of working with the product: (1) control center: (2) command line; and (3) programming.

  6. Phase IV of Drug Development

    OpenAIRE

    Viraj Suvarna

    2010-01-01

    Not all Phase IV studies are post-marketing surveillance (PMS) studies but every PMS study is a phase IV study. Phase IV is also an important phase of drug development. In particular, the real world effectiveness of a drug as evaluated in an observational, non-interventional trial in a naturalistic setting which complements the efficacy data that emanates from a pre-marketing randomized controlled trial (RCT). No matter how many patients are studied pre-marketing in a controlled environment, ...

  7. IVS contribution to ITRF2014

    Science.gov (United States)

    Bachmann, Sabine; Thaller, Daniela; Roggenbuck, Ole; Lösler, Michael; Messerschmitt, Linda

    2016-07-01

    Every few years the International Terrestrial Reference System (ITRS) Center of the International Earth Rotation and Reference Systems Service (IERS) decides to generate a new version of the International Terrestrial Reference Frame (ITRF). For the upcoming ITRF2014 the official contribution of the International VLBI Service for Geodesy and Astrometry (IVS) comprises 5796 combined sessions in SINEX file format from 1979.6 to 2015.0 containing 158 stations, overall. Nine AC contributions were included in the combination process, using five different software packages. Station coordinate time series of the combined solution show an overall repeatability of 3.3 mm for the north, 4.3 mm for the east and 7.5 mm for the height component over all stations. The minimum repeatabilities are 1.5 mm for north, 2.1 mm for east and 2.9 mm for height. One of the important differences between the IVS contribution to the ITRF2014 and the routine IVS combination is the omission of the correction for non-tidal atmospheric pressure loading (NTAL). Comparisons between the amplitudes of the annual signals derived by the VLBI observations and the annual signals from an NTAL model show that for some stations, NTAL has a high impact on station height variation. For other stations, the effect of NTAL is low. Occasionally other loading effects have a higher influence (e.g. continental water storage loading). External comparisons of the scale parameter between the VTRF2014 (a TRF based on combined VLBI solutions), DTRF2008 (DGFI-TUM realization of ITRS) and ITRF2008 revealed a significant difference in the scale. A scale difference of 0.11 ppb (i.e. 0.7 mm on the Earth's surface) has been detected between the VTRF2014 and the DTRF2008, and a scale difference of 0.44 ppb (i.e. 2.8 mm on the Earth's surface) between the VTRF2014 and ITRF2008. Internal comparisons between the EOP of the combined solution and the individual solutions from the AC contributions show a WRMS in X- and Y-Pole between

  8. Genetic and grade and tonnage models for sandstone-hosted roll-type uranium deposits, Texas Coastal Plain, USA

    Science.gov (United States)

    Hall, Susan M.; Mihalasky, Mark J.; Tureck, Kathleen; Hammarstrom, Jane M.; Hannon, Mark

    2017-01-01

    with either (1) organic-rich debris adjacent to large long-lived fluvial channels and barrier–bar sequences or (2) extrinsic reductants entrained in formation water or discrete gas that migrated into host units via faults and along the flanks of salt domes and shale diapirs. The southwestern portion of the region, the Rio Grande embayment, contains all the necessary factors required for roll-type uranium deposits. However, the eastern portion of the region, the Houston embayment, is challenged by a humid environment and a lack of source rock and transmissive units, which may combine to preclude the deposition of economic deposits. A grade and tonnage model for the Texas Coastal Plain shows that the Texas deposits represent a lower tonnage subset of roll-type deposits that occur around the world, and required aggregation of production centers into deposits based on geologic interpretation for the purpose of conducting a quantitative mineral resource assessment.

  9. Confirmatory Factor Analysis of the WAIS-IV/WMS-IV

    Science.gov (United States)

    Holdnack, James A.; Zhou, Xiaobin; Larrabee, Glenn J.; Millis, Scott R.; Salthouse, Timothy A.

    2011-01-01

    The Wechsler Adult Intelligence Scale-fourth edition (WAIS-IV) and the Wechsler Memory Scale-fourth edition (WMS-IV) were co-developed to be used individually or as a combined battery of tests. The independent factor structure of each of the tests has been identified; however, the combined factor structure has yet to be determined. Confirmatory…

  10. Confirmatory Factor Analysis of the WAIS-IV/WMS-IV

    Science.gov (United States)

    Holdnack, James A.; Zhou, Xiaobin; Larrabee, Glenn J.; Millis, Scott R.; Salthouse, Timothy A.

    2011-01-01

    The Wechsler Adult Intelligence Scale-fourth edition (WAIS-IV) and the Wechsler Memory Scale-fourth edition (WMS-IV) were co-developed to be used individually or as a combined battery of tests. The independent factor structure of each of the tests has been identified; however, the combined factor structure has yet to be determined. Confirmatory…

  11. Automated Grading of Gliomas using Deep Learning in Digital Pathology Images: A modular approach with ensemble of convolutional neural networks.

    Science.gov (United States)

    Ertosun, Mehmet Günhan; Rubin, Daniel L

    2015-01-01

    Brain glioma is the most common primary malignant brain tumors in adults with different pathologic subtypes: Lower Grade Glioma (LGG) Grade II, Lower Grade Glioma (LGG) Grade III, and Glioblastoma Multiforme (GBM) Grade IV. The survival and treatment options are highly dependent of this glioma grade. We propose a deep learning-based, modular classification pipeline for automated grading of gliomas using digital pathology images. Whole tissue digitized images of pathology slides obtained from The Cancer Genome Atlas (TCGA) were used to train our deep learning modules. Our modular pipeline provides diagnostic quality statistics, such as precision, sensitivity and specificity, of the individual deep learning modules, and (1) facilitates training given the limited data in this domain, (2) enables exploration of different deep learning structures for each module, (3) leads to developing less complex modules that are simpler to analyze, and (4) provides flexibility, permitting use of single modules within the framework or use of other modeling or machine learning applications, such as probabilistic graphical models or support vector machines. Our modular approach helps us meet the requirements of minimum accuracy levels that are demanded by the context of different decision points within a multi-class classification scheme. Convolutional Neural Networks are trained for each module for each sub-task with more than 90% classification accuracies on validation data set, and achieved classification accuracy of 96% for the task of GBM vs LGG classification, 71% for further identifying the grade of LGG into Grade II or Grade III on independent data set coming from new patients from the multi-institutional repository.

  12. Comparative Analysis of Inpatient Costs for Obstetrics and Gynecology Surgery Patients Treated With IV Acetaminophen and IV Opioids Versus IV Opioid-only Analgesia for Postoperative Pain.

    Science.gov (United States)

    Hansen, Ryan N; Pham, An T; Lovelace, Belinda; Balaban, Stela; Wan, George J

    2017-06-01

    Recovery from obstetrics and gynecology (OB/GYN) surgery, including hysterectomy and cesarean section delivery, aims to restore function while minimizing hospital length of stay (LOS) and medical expenditures. Our analyses compare OB/GYN surgery patients who received combination intravenous (IV) acetaminophen and IV opioid analgesia with those who received IV opioid-only analgesia and estimate differences in LOS, hospitalization costs, and opioid consumption. We performed a retrospective analysis of the Premier Database between January 2009 and June 2015, comparing OB/GYN surgery patients who received postoperative pain management with combination IV acetaminophen and IV opioids with those who received only IV opioids starting on the day of surgery and continuing up to the second postoperative day. We performed instrumental variable 2-stage least-squares regressions controlling for patient and hospital covariates to compare the LOS, hospitalization costs, and daily opioid doses (morphine equivalent dose) of IV acetaminophen recipients with that of opioid-only analgesia patients. We identified 225 142 OB/GYN surgery patients who were eligible for our study of whom 89 568 (40%) had been managed with IV acetaminophen and opioids. Participants averaged 36 years of age and were predominantly non-Hispanic Caucasians (60%). Multivariable regression models estimated statistically significant differences in hospitalization cost and opioid use with IV acetaminophen associated with $484.4 lower total hospitalization costs (95% CI = -$760.4 to -$208.4; P = 0.0006) and 8.2 mg lower daily opioid use (95% CI = -10.0 to -6.4), whereas the difference in LOS was not significant, at -0.09 days (95% CI = -0.19 to 0.01; P = 0.07). Compared with IV opioid-only analgesia, managing post-OB/GYN surgery pain with the addition of IV acetaminophen is associated with decreased hospitalization costs and reduced opioid use.

  13. DSM-IV Progress Report.

    Science.gov (United States)

    Hohenshil, Thomas H.

    1992-01-01

    Notes that Diagnostic and Statistical Manual of Mental Disorders fourth edition (DSM-IV) will become one of most frequently used reference documents in counseling profession. Describes progress being made in development of DSM-IV, scheduled for publication in 1994. Describes revision process and proposed organizational changes and new diagnostic…

  14. Pulsatile magneto-hydrodynamic blood flows through porous blood vessels using a third grade non-Newtonian fluids model.

    Science.gov (United States)

    Akbarzadeh, Pooria

    2016-04-01

    In this paper, the unsteady pulsatile magneto-hydrodynamic blood flows through porous arteries concerning the influence of externally imposed periodic body acceleration and a periodic pressure gradient are numerically simulated. Blood is taken into account as the third-grade non-Newtonian fluid. Besides the numerical solution, for small Womersley parameter (such as blood flow through arterioles and capillaries), the analytical perturbation method is used to solve the nonlinear governing equations. Consequently, analytical expressions for the velocity profile, wall shear stress, and blood flow rate are obtained. Excellent agreement between the analytical and numerical predictions is evident. Also, the effects of body acceleration, magnetic field, third-grade non-Newtonian parameter, pressure gradient, and porosity on the flow behaviors are examined. Some important conclusions are that, when the Womersley parameter is low, viscous forces tend to dominate the flow, velocity profiles are parabolic in shape, and the center-line velocity oscillates in phase with the driving pressure gradient. In addition, by increasing the pressure gradient, the mean value of the velocity profile increases and the amplitude of the velocity remains constant. Also, when non-Newtonian effect increases, the amplitude of the velocity profile.

  15. Polymer electrolyte membrane fuel cell grade hydrogen production by methanol steam reforming: A comparative multiple reactor modeling study

    Science.gov (United States)

    Katiyar, Nisha; Kumar, Shashi; Kumar, Surendra

    2013-12-01

    Analysis of a fuel processor based on methanol steam reforming has been carried out to produce fuel cell grade H2. Six reactor configurations namely FBR1 (fixed bed reactor), MR1 (H2 selective membrane reactor with one reaction tube), MR2 (H2 selective membrane reactor with two reaction tubes), FBR2 (FBR1 + preferential CO oxidation (PROX) reactor), MR3 (MR1 + PROX), and MR4 (MR2 + PROX) are evaluated by simulation to identify the suitable processing scheme. The yield of H2 is significantly affected by H2 selective membrane, residence time, temperature, and pressure conditions at complete methanol conversion. The enhancement in residence time in MR2 by using two identical reaction tubes provides H2 yield of 2.96 with 91.25 mol% recovery at steam/methanol ratio of 1.5, pressure of 2 bar and 560 K temperature. The exit retentate gases from MR2 are further treated in PROX reactor of MR4 to reduce CO concentration to 4.1 ppm to ensure the safe discharge to the environment. The risk of carbon deposition on reforming catalyst is highly reduced in MR4, and MR4 reactor configuration generates 7.4 NL min-1 of CO free H2 from 0.12 mol min-1 of methanol which can provide 470 W PEMFC feedstock requirement. Hence, process scheme in MR4 provides a compact and innovative fuel cell grade H2 generating unit.

  16. The componential model of reading: predicting first grade reading performance of culturally diverse students from ecological, psychological, and cognitive factors assessed at kindergarten entry.

    Science.gov (United States)

    Ortiz, Miriam; Folsom, Jessica S; Al Otaiba, Stephanie; Greulich, Luana; Thomas-Tate, Shurita; Connor, Carol M

    2012-01-01

    This study, framed by the component model of reading (CMR), examined the relative importance of kindergarten-entry predictors of first grade reading performance. Specifically, elements within the ecological domain included dialect, maternal education, amount of preschool, and home literacy; elements within the psychological domain included teacher-reported academic competence, social skills, and behavior; and elements within the cognitive domain included initial vocabulary, phonological, and morpho-syntactic skills, and alphabetic and word recognition skills. Data were obtained for 224 culturally diverse kindergarteners (58% Black, 34% White, and 8% Hispanic or other; 58% received free or reduced-price lunch) from a larger study conducted in seven predominantly high poverty schools (n = 20 classrooms) in a midsized city school district in northern Florida. Results from a hierarchical multiple regression (with variables in the ecological domain entered first, followed by the psychological and cognitive domains) revealed a model that explained roughly 56% of the variance in first grade reading achievement, using fall-of-kindergarten predictors. Letter-word reading and morpho-syntactic skill were the strongest significant predictors. The findings largely support the CMR model as a means to understand individual differences in reading acquisition and, in turn, to support data-based instructional decisions for a wider range of children.

  17. Application of Response Surface Methodology for Modeling of Postweld Heat Treatment Process in a Pressure Vessel Steel ASTM A516 Grade 70.

    Science.gov (United States)

    Peasura, Prachya

    2015-01-01

    This research studied the application of the response surface methodology (RSM) and central composite design (CCD) experiment in mathematical model and optimizes postweld heat treatment (PWHT). The material of study is a pressure vessel steel ASTM A516 grade 70 that is used for gas metal arc welding. PWHT parameters examined in this study included PWHT temperatures and time. The resulting materials were examined using CCD experiment and the RSM to determine the resulting material tensile strength test, observed with optical microscopy and scanning electron microscopy. The experimental results show that using a full quadratic model with the proposed mathematical model is YTS = -285.521 + 15.706X1 + 2.514X2 - 0.004X1(2) - 0.001X2(2) - 0.029X1X2. Tensile strength parameters of PWHT were optimized PWHT time of 5.00 hr and PWHT temperature of 645.75°C. The results show that the PWHT time is the dominant mechanism used to modify the tensile strength compared to the PWHT temperatures. This phenomenon could be explained by the fact that pearlite can contribute to higher tensile strength. Pearlite has an intensity, which results in increased material tensile strength. The research described here can be used as material data on PWHT parameters for an ASTM A516 grade 70 weld.

  18. Thermal rectification in graded materials.

    Science.gov (United States)

    Wang, Jiao; Pereira, Emmanuel; Casati, Giulio

    2012-07-01

    In order to identify the basic conditions for thermal rectification we investigate a simple model with nonuniform, graded mass distribution. The existence of thermal rectification is theoretically predicted and numerically confirmed, suggesting that thermal rectification is a typical occurrence in graded systems, which are likely to be natural candidates for the actual fabrication of thermal diodes. In view of practical implications, the dependence of rectification on the asymmetry and system's size is studied.

  19. Preferences With Grades of Indecisiveness

    OpenAIRE

    Stefania Minardi; Andrei Savochkin

    2013-01-01

    Departing from the traditional approach to modeling an agent who finds it difficult to make clear-cut comparisons between alternatives, we introduce the notion of graded preferences: Given two alternatives, the agent reports a number between 0 and 1, which reflects her inclination to prefer the first option over the second or, put differently, how confident she is about the superiority of the first one. In the classical framework of uncertainty, we derive a representation of a graded preferen...

  20. PENGARUH PEMBELAJARAN STUDENT TEAM ACHIEVEMENT DIVISION DAN DISKUSI TERHADAP HASIL BELAJAR IPA KELAS IV SD

    Directory of Open Access Journals (Sweden)

    Lalu Warige Hadinata

    2017-07-01

    Full Text Available The research aims to determine the effect of STAD and discussion on learning outcomes of classroom learning for science at 4th grade. The design of this research used a quasi-experimental design with nonequivalent control group design. Research was conducted in the 4th grade students of SDN 2 Kekeri West Lombok It’s consist of 19 students in 4th grade/a as an STAD and 19 students at 4th grade/b as the discussion. Analysis of learning outcomes data using the Independent Sample T Test with IBM SPSS 24. The analysis showed: (1 there were no significant differences in learning outcomes among students that learned STAD and students that learned discussion. (2 STAD and discussion has an effect on student learning outcomes of 4th grade. Penelitian bertujuan untuk mengetahui perbedaan hasil belajar STAD dan diskusi pelajaran IPA kelas IV. Rancangan penelitian ini menggunakan eksperimen semu dengan bentuk nonequivalent control group design. Penelitian dilaksanakan pada siswa kelas IV SDN 2 Kekeri Lombok Barat terdiri dari 19 siswa kelas IV/a dengan STAD dan 19 siswa kelas IV/b dengan diskusi. Analisis data hasil belajar menggunakan Independent Sample T Test dengan IBM SPSS 24. Hasil analisis menunjukkan (1 tidak ada perbedaan hasil belajar yang signifikan antara siswa yang dibelajarkan STAD dan siswa yang dibelajarkan diskusi. (2 STAD dan diskusi mampu meningkatkan hasil belajar siswa pada kelas IV.