194 research outputs found
COMPARISON OF MODELS AND ESTIMATION OF MISSING PARAMETERS OF SOME MATHEMATICAL MODELS RELATED TO IN SITU DRY MATTER DEGRADATION
ABSTRACT The aim of this study was to estimate missing parameters of the models such as the Orskov, Gompertz, Logistic and Richard models. These missing parameters for some models were estimated on the rapidly soluble fraction, the insoluble but potentially degradable fraction and the partial potentially degradable fraction. No difference was found among the values of these parameters (P>0.05), except for the constant rate of degredation. Besides, other missing parameters of the models studied were: partial dry matter disappearance in rumen for the percent rate at time t (t p ) and Rt p , rate of the partial dry matter disapparance in rumen at the time t p (t 0 , t 25 , t 50 , t 75 and t 95 ). These values and formulas for these values in different time intervals were also obtained. The second objective was especially on the comparison of the results of all t p`s (t 25 , t 50 , t 75 and t 95 ) and Rt p`s (Rt 0 , Rt 25 , Rt 50 , Rt 75 and Rt 95 ) in the models. The results of all t p`s and Rt p`s in the models were compatible with each other (P>0.05). The thirth objective was to investigate the fit performance of the models for in situ degradation studies. Some criteria used with the purpose of evaluating performances of models studied were on the analysis of residual (The Runs test and Durbin Watson) and goodness-of-fit (Residual Mean Square, the coefficient of determination and F-ratio). As a result of this study, while the Orskov model showed the best statistical performance and goodness of fit, the Richard model showed the worst. it is determined that the Gompertz model showed a systematic deviation from the data and is not appropriate for describing in situ data
Chemical Doping of the Organic Semiconductor C8-BTBT-C8 Using an Aqueous Iodine Solution for Device Mobility Enhancement
The performance of organic field-effect transistors is still severely limited by factors such as contact resistance and charge trapping. Chemical doping is considered to be a promising key enabler for improving device performance, although there is a limited number of established doping protocols as well as a lack of understanding of the doping mechanisms. Here, a very simple doping methodology based on exposing an organic semiconductor thin film to an aqueous iodine solution is reported. The doped devices exhibit enhanced device mobility, which becomes channel-length independent, a decreased threshold voltage and a reduction in the density of interfacial traps. The device OFF current is not altered, which is in agreement with the spectroscopic data that points out that no charge transfer processes are occurring. Kelvin probe force microscopy characterization of the devices under operando conditions unambiguously proves that an important reduction of the contact resistance takes place after their exposition to the iodine solution, reaching almost ohmic contact
Combining navigator and optical prospective motion correction for high-quality 500 μm resolution quantitative multi-parameter mapping at 7T
PURPOSE: High-resolution quantitative multi-parameter mapping shows promise for non-invasively characterizing human brain microstructure but is limited by physiological artifacts. We implemented corrections for rigid head movement and respiration-related B0-fluctuations and evaluated them in healthy volunteers and dementia patients. METHODS: Camera-based optical prospective motion correction (PMC) and FID navigator correction were implemented in a gradient and RF-spoiled multi-echo 3D gradient echo sequence for mapping proton density (PD), longitudinal relaxation rate (R1) and effective transverse relaxation rate (R2*). We studied their effectiveness separately and in concert in young volunteers and then evaluated the navigator correction (NAVcor) with PMC in a group of elderly volunteers and dementia patients. We used spatial homogeneity within white matter (WM) and gray matter (GM) and scan-rescan measures as quality metrics. RESULTS: NAVcor and PMC reduced artifacts and improved the homogeneity and reproducibility of parameter maps. In elderly participants, NAVcor improved scan-rescan reproducibility of parameter maps (coefficient of variation decreased by 14.7% and 11.9% within WM and GM respectively). Spurious inhomogeneities within WM were reduced more in the elderly than in the young cohort (by 9% vs. 2%). PMC increased regional GM/WM contrast and was especially important in the elderly cohort, which moved twice as much as the young cohort. We did not find a significant interaction between the two corrections. CONCLUSION: Navigator correction and PMC significantly improved the quality of PD, R1, and R2* maps, particularly in less compliant elderly volunteers and dementia patients
Micro and nano-patterning of single-crystal diamond by swift heavy ion irradiation
This paper presents experimental data and analysis of the structural damage caused by swift-heavy ion irradiation of single-crystal diamond. The patterned buried structural damage is shown to generate, via swelling, a mirror- pattern on the sample surface, which remains largely damage-free. While extensive results are available for light ion implantations, this effect is reported here for the first time in the heavy ion regime,where a completely different range of input parameters (in terms of ion species, energy, stopping power, etc.) is available for customized irradiation. The chosen ion species are Au and Br, in the energy range 10–40 MeV. The observed patterns, as characterized by profilometry and atomic force microscopy, are reported in a series ofmodel experiments,which show swelling patterns ranging from a few nm to above 200 nm. Moreover, a systematic phenomenological modeling is presented, inwhich surface swelling measurements are correlated to buried crystal damage. A comparison ismade with data for light ion implantations, showing good compatibilitywith the proposedmodels. The modeling presented in thiswork can be useful for the design and realization of micropatterned surfaces in single crystal diamond, allowing generating highly customized structures by combining appropriately chosen irradiation parameters and masks
Intramolecular Force Contrast and Dynamic Current-Distance Measurements at Room Temperature
Next-generation sequencing reveals deep intronic cryptic ABCC8 and HADH splicing founder mutations causing hyperinsulinism by pseudoexon activation
Copyright © 2013 The American Society of Human Genetics. Published by Elsevier Inc.Next-generation sequencing (NGS) enables analysis of the human genome on a scale previously unachievable by Sanger sequencing. Exome sequencing of the coding regions and conserved splice sites has been very successful in the identification of disease-causing mutations, and targeting of these regions has extended clinical diagnostic testing from analysis of fewer than ten genes per phenotype to more than 100. Noncoding mutations have been less extensively studied despite evidence from mRNA analysis for the existence of deep intronic mutations in >20 genes. We investigated individuals with hyperinsulinaemic hypoglycaemia and biochemical or genetic evidence to suggest noncoding mutations by using NGS to analyze the entire genomic regions of ABCC8 (117 kb) and HADH (94 kb) from overlapping ~10 kb PCR amplicons. Two deep intronic mutations, c.1333-1013A>G in ABCC8 and c.636+471G>T HADH, were identified. Both are predicted to create a cryptic splice donor site and an out-of-frame pseudoexon. Sequence analysis of mRNA from affected individuals' fibroblasts or lymphoblastoid cells confirmed mutant transcripts with pseudoexon inclusion and premature termination codons. Testing of additional individuals showed that these are founder mutations in the Irish and Turkish populations, accounting for 14% of focal hyperinsulinism cases and 32% of subjects with HADH mutations in our cohort. The identification of deep intronic mutations has previously focused on the detection of aberrant mRNA transcripts in a subset of disorders for which RNA is readily obtained from the target tissue or ectopically expressed at sufficient levels. Our approach of using NGS to analyze the entire genomic DNA sequence is applicable to any disease
Characteristics of patients operated for primary hyperparathyroidism at university hospitals in Türkiye: Differences among Türkiye's geographical regions
Purpose: The aim of this study was to define the clinical and laboratory characteristics of patients operated on for primary hyperpatathyroidism (PHPT) at university hospitals in Türkiye, and to investigate the differences in the clinical presentations of the disease between different geographical regions. Methods: Patients operated on for PHPT in the university hospitals of Türkiye were included in the study. The demographic, clinical, and laboratory findings and the operational data of the patients were investigated according to the whole country and to different geographical regions. Comparisons were performed according to whole country and regions. Results: A total of 1,162 cases were included in the study from different regions and 20 university hospitals. The mean age of patients was 52.4 ± 0.38 (mean ± standard error) in the general population of Türkiye. The rates of hypertension, urolithiasis, bone disease and 25-hydroxyvitamin D insufficiency were 35%, 18.6%, 67.6%, and 63%, respectively. The median parathormone (PTH), serum total calcium (Ca+2) and phosphorus value were 220 pg/mL (range, 70-2,500 pg/mL), 11.2 mg/dL (range, 9.5-11.2 mg/dL), and 2.4 mg/dL (range, 1-4.7 mg/dL), respectively. The median size of the adenomas resected was 16 mm (range, 4-70 mm). Significant differences were observed in the clinical and laboratory findings of the patients operated on due to PHPT between different geographical regions of Türkiye (P < 0.05). Conclusion: The clinical and laboratory characteristics of the patients with PHPT in different geographical regions of Türkiye differ. Furthermore, the general findings of the cases in Türkiye give us a hint that the severity of the disease here is somewhere between Eastern and Western countries. Copyright © 2016, the Korean Surgical Society
Micro and nano-patterning of single-crystal diamond by swift heavy ion irradiation
© 2016 Elsevier B.V.This paper presents experimental data and analysis of the structural damage caused by swift-heavy ion irradiation of single-crystal diamond. The patterned buried structural damage is shown to generate, via swelling, a mirror-pattern on the sample surface, which remains largely damage-free. While extensive results are available for light ion implantations, this effect is reported here for the first time in the heavy ion regime, where a completely different range of input parameters (in terms of ion species, energy, stopping power, etc.) is available for customized irradiation. The chosen ion species are Au and Br, in the energy range 10–40 MeV. The observed patterns, as characterized by profilometry and atomic force microscopy, are reported in a series of model experiments, which show swelling patterns ranging from a few nm to above 200 nm. Moreover, a systematic phenomenological modeling is presented, in which surface swelling measurements are correlated to buried crystal damage. A comparison is made with data for light ion implantations, showing good compatibility with the proposed models. The modeling presented in this work can be useful for the design and realization of micropatterned surfaces in single crystal diamond, allowing generating highly customized structures by combining appropriately chosen irradiation parameters and masks.GG acknowledges support from the ALBA synchrotron, W. Schildkamp for inspiring discussions on the behaviour of diamond and J. Ferrer for his help in experiment preparation.
GG, MD-H, VT-M, OP-R and JO acknowledge the projects MAT-2011-28379-C03-02 of the Spanish Ministry of Economy and Competitiveness, TECHNOFUSION(II)CM (S2013/MAE2745) of the Community of Madrid, and Moncloa Campus of International Excellence (UCM-UPM) foundation for offering a PICATA postdoctoral fellowship (OP-R).
FP is supported by the “DiNaMo” project no. 157660 funded by National Institute of Nuclear Physics. PO is supported by the FIRB “Futuro in Ricerca 2010” project (CUP code: D11J11000450001) funded by MIUR and by the “A.Di.N-Tech.” project (CUP code: D15E13000130003) funded by the University of Torino and “Compagnia di San Paolo”. The MeV ion beam implantations performed at the INFN Legnaro National Laboratories was supported by the “Dia.Fab.” experiment, and those at the INFN LABEC Laboratory by the “FARE” and “CICAS” experiments.
NMP is supported by the European Research Council (ERC StG Ideas 2011 BIHSNAM no. 279985, ERC PoC 2013-2 KNOTOUGH no. 632277 and ERC PoC 2015 SILKENE no. 693670), by the European Commission under the Graphene Flagship (“Nanocomposites”, no. 604391). FB acknowledges support from BIHSNAM.
LL-M and CO acknowledge the Spanish MINECO through the Severo Ochoa Program (SEV-2015-0496) and MAT2013-47869-C4-1-P.
CO acknowledges the specific agreement between ICMAB-CSIC and the Synchrotron Light Facility ALBA
A HIF1α Regulatory Loop Links Hypoxia and Mitochondrial Signals in Pheochromocytomas
Pheochromocytomas are neural crest–derived tumors that arise from inherited or sporadic mutations in at least six independent genes. The proteins encoded by these multiple genes regulate distinct functions. We show here a functional link between tumors with VHL mutations and those with disruption of the genes encoding for succinate dehydrogenase (SDH) subunits B (SDHB) and D (SDHD). A transcription profile of reduced oxidoreductase is detected in all three of these tumor types, together with an angiogenesis/hypoxia profile typical of VHL dysfunction. The oxidoreductase defect, not previously detected in VHL-null tumors, is explained by suppression of the SDHB protein, a component of mitochondrial complex II. The decrease in SDHB is also noted in tumors with SDHD mutations. Gain-of-function and loss-of-function analyses show that the link between hypoxia signals (via VHL) and mitochondrial signals (via SDH) is mediated by HIF1α. These findings explain the shared features of pheochromocytomas with VHL and SDH mutations and suggest an additional mechanism for increased HIF1α activity in tumors
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