Non-isothermal crystallization of poly(etheretherketone) aromatic polymer composite

NASA Technical Reports Server (NTRS)

Cebe, Peggy

1988-01-01

The nonisothermal crystallization kinetics of PEEK APC-2 and of 450G neat resin PEEK material were compared using a differential scanning calorimeter to monitor heat flow during crystallization; the effects of cooling rate on the crystallization temperature, the degree of crystallinity, and the conversion rate were investigated. A modified Avrami (1940) analysis was used to describe nonisothermal crystallization kinetics. It was found that, compared with the 450G neat resin PEEK, the nonisothermal crystallization of the PEEK APC-2 composite is characterized by higher initiation temperature, higher heat flow maximum temperature, and greater relative conversion by primary processes.

Conversion in laparoscopic colorectal cancer surgery: impact on short- and long-term outcome.

PubMed

Scheidbach, Hubert; Garlipp, Benjamin; Oberländer, Henrik; Adolf, Daniela; Köckerling, Ferdinand; Lippert, Hans

2011-12-01

Despite the well-documented safety and effectiveness of laparoscopic colorectal surgery in curative intention, the role of conversion and its impact on short- and long-term outcome after resection of a carcinoma are unclear and continue to give rise to controversial discussion. Within the framework of a prospective, multicenter observational study (Laparoscopic Colorectal Surgery Study Group), into which a total of 5,863 patients from 69 hospitals were recruited over a period of 10 years, a subgroup of all patients who had undergone curative resection was analyzed with regard to the effects of conversion. Of the 1409 patients who had undergone curative resection for colorectal carcinoma, conversion had to be performed in 80 (5.7%) cases for the most diverse reasons. The duration of surgery (median: 183 vs. 241 minutes; P<.001) was significantly longer in the conversion group. Perioperatively, significant disadvantages were noted in converted patients in terms of intraoperative blood loss (median: 243 vs. 573 mL, P<.001), need for perioperative blood transfusion (10.8% vs. 33.8%; P<.001), and resumption of bowel movement (median: after 3 vs. 4 days; P<.001). With regard to postoperative morbidity, significant disadvantages were observed in converted patients, in particular in terms of specific surgical complications, including a higher rate of anastomotic insufficiency (5.0% vs. 13.8%; P=.003) and a higher reoperation rate (4.9% vs. 15.0%; P=.001). In the long term, conversion was associated with lower overall survival, but not with poorer disease-free survival. Significantly higher postoperative morbidity was observed in patients after conversion, in particular in terms of specific surgical complications. In addition, conversion is associated with overall lower survival but not with poorer disease-free survival.

There Is a Significant Discrepancy Between "Big Data" Database and Original Research Publications on Hip Arthroscopy Outcomes: A Systematic Review.

PubMed

Sochacki, Kyle R; Jack, Robert A; Safran, Marc R; Nho, Shane J; Harris, Joshua D

2018-06-01

The purpose of this study was to compare (1) major complication, (2) revision, and (3) conversion to arthroplasty rates following hip arthroscopy between database studies and original research peer-reviewed publications. A systematic review was performed using PRISMA guidelines. PubMed, SCOPUS, SportDiscus, and Cochrane Central Register of Controlled Trials were searched for studies that investigated major complication (dislocation, femoral neck fracture, avascular necrosis, fluid extravasation, septic arthritis, death), revision, and hip arthroplasty conversion rates following hip arthroscopy. Major complication, revision, and conversion to hip arthroplasty rates were compared between original research (single- or multicenter therapeutic studies) and database (insurance database using ICD-9/10 and/or current procedural terminology coding terminology) publishing studies. Two hundred seven studies (201 original research publications [15,780 subjects; 54% female] and 6 database studies [20,825 subjects; 60% female]) were analyzed (mean age, 38.2 ± 11.6 years old; mean follow-up, 2.7 ± 2.9 years). The database studies had a significantly higher age (40.6 + 2.8 vs 35.4 ± 11.6), body mass index (27.4 ± 5.6 vs 24.9 ± 3.1), percentage of females (60.1% vs 53.8%), and longer follow-up (3.1 ± 1.6 vs 2.7 ± 3.0) compared with original research (P < .0001 for all). Ninety-seven (0.6%) major complications occurred in the individual studies, and 95 (0.8%) major complications occurred in the database studies (P = .029; relative risk [RR], 1.3). There was a significantly higher rate of femoral neck fracture (0.24% vs 0.03%; P < .0001; RR, 8.0), and hip dislocation (0.17% vs 0.06%; P = .023; RR, 2.2) in the database studies. Reoperations occurred at a significantly higher rate in the database studies (11.1% vs 7.3%; P < .001; RR, 1.5). There was a significantly higher rate of conversion to arthroplasty in the database studies (8.0% vs 3.7%; P < .001; RR, 2.2). Database studies report significantly increased major complication, revision, and conversion to hip arthroplasty rates compared with original research investigations of hip arthroscopy outcomes. Level IV, systematic review of Level I-IV studies. Copyright © 2018 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Rates and Predictors of Conversion to Schizophrenia or Bipolar Disorder Following Substance-Induced Psychosis.

PubMed

Starzer, Marie Stefanie Kejser; Nordentoft, Merete; Hjorthøj, Carsten

2018-04-01

The authors investigated the rates of conversion to schizophrenia and bipolar disorder after a substance-induced psychosis, as well as risk factors for conversion. All patient information was extracted from the Danish Civil Registration System and the Psychiatric Central Research Register. The study population included all persons who received a diagnosis of substance-induced psychosis between 1994 and 2014 (N=6,788); patients were followed until first occurrence of schizophrenia or bipolar disorder or until death, emigration, or August 2014. The Kaplan-Meier method was used to obtain cumulative probabilities for the conversion from a substance-induced psychosis to schizophrenia or bipolar disorder. Cox proportional hazards regression models were used to calculate hazard ratios for all covariates. Overall, 32.2% (95% CI=29.7-34.9) of patients with a substance-induced psychosis converted to either bipolar or schizophrenia-spectrum disorders. The highest conversion rate was found for cannabis-induced psychosis, with 47.4% (95% CI=42.7-52.3) converting to either schizophrenia or bipolar disorder. Young age was associated with a higher risk of converting to schizophrenia. Self-harm after a substance-induced psychosis was significantly linked to a higher risk of converting to both schizophrenia and bipolar disorder. Half the cases of conversion to schizophrenia occurred within 3.1 years after a substance-induced psychosis, and half the cases of conversion to bipolar disorder occurred within 4.4 years. Substance-induced psychosis is strongly associated with the development of severe mental illness, and a long follow-up period is needed to identify the majority of cases.

Primary vs Conversion Total Hip Arthroplasty: A Cost Analysis

PubMed Central

Chin, Garwin; Wright, David J.; Snir, Nimrod; Schwarzkopf, Ran

2018-01-01

Introduction Increasing hip fracture incidence in the United States is leading to higher occurrences of conversion total hip arthroplasty (THA) for failed surgical treatment of the hip. In spite of studies showing higher complication rates in conversion THA, the Centers for Medicare and Medicaid services currently bundles conversion and primary THA under the same diagnosis-related group. We examined the cost of treatment of conversion THA compared with primary THA. Our hypothesis is that conversion THA will have higher cost and resource use than primary THA. Methods Fifty-one consecutive conversion THA patients (Current Procedure Terminology code 27132) and 105 matched primary THA patients (Current Procedure Terminology code 27130) were included in this study. The natural log-transformed costs for conversion and primary THA were compared using regression analysis. Age, gender, body mass index, American Society of Anesthesiologist, Charlson comorbidity score, and smoker status were controlled in the analysis. Conversion THA subgroups formed based on etiology were compared using analysis of variance analysis. Results Conversion and primary THAs were determined to be significantly different (P < .05) and greater in the following costs: hospital operating direct cost (29.2% greater), hospital operating total cost (28.8% greater), direct hospital cost (24.7% greater), and total hospital cost (26.4% greater). Conclusions Based on greater hospital operating direct cost, hospital operating total cost, direct hospital cost, and total hospital cost, conversion THA has significantly greater cost and resource use than primary THA. In order to prevent disincentives for treating these complex surgical patients, reclassification of conversion THA is needed, as they do not fit together with primary THA. PMID:26387923

Gallbladder Nonvisualization in Cholecystectomy: A Factor for Conversion.

PubMed

Slack, Daniel R; Grisby, Shaunda; Dike, Uzoamaka Kimberly; Kohli, Harjeet

2018-01-01

Many risk factors have been identified in minimally invasive cholecystectomies that lead to higher complications and conversion rates. No study that we encountered looked at nonvisualization of the gallbladder (GB) during surgery as a risk factor. We hypothesized that nonvisualization was associated with an increased risk of complications and could be an early intraoperative identifier of a higher risk procedure. Recognizing this could allow surgeons to be aware of potential risks and to be more likely to convert to open for the safety of the patient. We looked at minimally invasive cholecystectomies performed at our institution from January 2015 through April 2016 and had the performing resident fill out a survey after the surgery. Outcomes were conversion rates, intraoperative complications, and blood loss and were analyzed via Pearson χ 2 test or Mann-Whitney U test. The primary outcome showed a conversion rate of 37% in nonvisualized GBs versus 0% in visualized ( P = .001). Secondary outcomes showed significant differences in GB perforations (74% vs 13%, P = .001), omental vessel bleeding (16% vs. 0%, P = .005), and EBL (46 mL vs 29 mL, P = .001). Intraoperative nonvisualization of the GB after adequate positioning caused significantly increased risk of intraoperative complications and conversion. This knowledge could be useful during intraoperative assessment, to decide whether a case should be continued as a minimally invasive procedure or converted early to help reduce risk to the patient. Further randomized controlled studies should be performed to further demonstrate the value of this assessment.

Interaction of H2 @C60 and nitroxide through conformationally constrained peptide bridges.

PubMed

Garbuio, Luca; Li, Yongjun; Antonello, Sabrina; Gascón, José A; Lawler, Ronald G; Lei, Xuegong; Murata, Yasujiro; Turro, Nicholas J; Maran, Flavio

2014-01-01

We synthesized two molecular systems, in which an endofullerene C60 , incarcerating one hydrogen molecule (H2 @C60 ) and a nitroxide radical are connected by a folded 310 -helical peptide. The difference between the two molecules is the direction of the peptide orientation. The nuclear spin relaxation rates and the para → ortho conversion rate of the incarcerated hydrogen molecule were determined by (1) H NMR spectroscopy. The experimental results were analyzed using DFT-optimized molecular models. The relaxation rates and the conversion rates of the two peptides fall in the expected distance range. One of the two peptides is particularly rigid and thus ideal to keep the H2 @C60 /nitroxide separation, r, as large and controlled as possible, which results in particularly low relaxation and conversion rates. Despite the very similar optimized distance, however, the rates measured with the other peptide are considerably higher and thus are compatible with a shorter effective distance. The results strengthen the outcome of previous investigations that while the para → ortho conversion rates satisfactorily obey the Wigner's theory, the nuclear spin relaxation rates are in excellent agreement with the Solomon-Bloembergen equation predicting a 1/r(6) dependence. © 2013 The American Society of Photobiology.

Expressed parental concern regarding childhood stuttering and the Test of Childhood Stuttering.

PubMed

Tumanova, Victoria; Choi, Dahye; Conture, Edward G; Walden, Tedra A

The purpose of the present study was to determine whether the Test of Childhood Stuttering observational rating scales (TOCS; Gillam et al., 2009) (1) differed between parents who did versus did not express concern (independent from the TOCS) about their child's speech fluency; (2) correlated with children's frequency of stuttering measured during a child-examiner conversation; and (3) correlated with the length and complexity of children's utterances, as indexed by mean length of utterance (MLU). Participants were 183 young children ages 3:0-5:11. Ninety-one had parents who reported concern about their child's stuttering (65 boys, 26 girls) and 92 had parents who reported no such concern (50 boys, 42 girls). Participants' conversational speech during a child-examiner conversation was analyzed for (a) frequency of occurrence of stuttered and non-stuttered disfluencies, and (b) MLU. Besides expressing concern or lack thereof about their child's speech fluency, parents completed the TOCS observational rating scales documenting how often they observe different disfluency types in speech of their children, as well as disfluency-related consequences. There were three main findings. First, parents who expressed concern (independently from the TOCS) about their child's stuttering reported significantly higher scores on the TOCS Speech Fluency and Disfluency-Related Consequences rating scales. Second, children whose parents rated them higher on the TOCS Speech Fluency rating scale produced more stuttered disfluencies during a child-examiner conversation. Third, children with higher scores on the TOCS Disfluency-Related Consequences rating scale had shorter MLU during child-examiner conversation, across age and level of language ability. Findings support the use of the TOCS observational rating scales as one documentable, objective means to determine parental perception of and concern about their child's stuttering. Findings also support the notion that parents are reasonably accurate, if not reliable, judges of the quantity and quality (i.e., stuttered vs. non-stuttered) of their child's speech disfluencies. Lastly, findings that some children may decrease their verbal output in attempts to minimize instances of stuttering - as indexed by relatively low MLU and a high TOCS Disfluency-Related Consequences scores - provides strong support for sampling young children's speech and language across various situations to obtain the most representative index possible of the child's MLU and associated instances of stuttering. Copyright © 2018 Elsevier Inc. All rights reserved.

Use of Hip Arthroscopy and Risk of Conversion to Total Hip Arthroplasty: A Population-Based Analysis.

PubMed

Schairer, William W; Nwachukwu, Benedict U; McCormick, Frank; Lyman, Stephen; Mayman, David

2016-04-01

To use population-level data to (1) evaluate the conversion rate of total hip arthroplasty (THA) within 2 years of hip arthroscopy and (2) assess the influence of age, arthritis, and obesity on the rate of conversion to THA. We used the State Ambulatory Surgery Databases and State Inpatient Databases for California and Florida from 2005 through 2012, which contain 100% of patient visits. Hip arthroscopy patients were tracked for subsequent primary THA within 2 years. Out-of-state patients and patients with less than 2 years follow-up were excluded. Multivariate analysis identified risks for subsequent hip arthroplasty after arthroscopy. We identified 7,351 patients who underwent hip arthroscopy with 2 years follow-up. The mean age was 43.9 ± 13.7 years, and 58.8% were female patients. Overall, 11.7% of patients underwent THA conversion within 2 years. The conversion rate was lowest in patients aged younger than 40 years (3.0%) and highest in the 60- to 69-year-old group (35.0%) (P < .001). We found an increased risk of THA conversion in older patients and in patients with osteoarthritis or obesity at the time of hip arthroscopy. Patients treated at high-volume hip arthroscopy centers had a lower THA conversion rate than those treated at low-volume centers (15.1% v 9.7%, P < .001). Hip arthroscopy is performed in patients of various ages, including middle-aged and elderly patients. Older patients have a higher rate of conversion to THA, as do patients with osteoarthritis or obesity. Level III, retrospective comparative study. Copyright © 2016 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Multi-keV x-ray sources from metal-lined cylindrical hohlraums

NASA Astrophysics Data System (ADS)

Jacquet, L.; Girard, F.; Primout, M.; Villette, B.; Stemmler, Ph.

2012-08-01

As multi-keV x-ray sources, plastic hohlraums with inner walls coated with titanium, copper, and germanium have been fired on Omega in September 2009. For all the targets, the measured and calculated multi-keV x-ray power time histories are in a good qualitative agreement. In the same irradiation conditions, measured multi-keV x-ray conversion rates are ˜6%-8% for titanium, ˜2% for copper, and ˜0.5% for germanium. For titanium and copper hohlraums, the measured conversion rates are about two times higher than those given by hydroradiative computations. Conversely, for the germanium hohlraum, a rather good agreement is found between measured and computed conversion rates. To explain these findings, multi-keV integrated emissivities calculated with RADIOM [M. Busquet, Phys. Fluids 85, 4191 (1993)], the nonlocal-thermal-equilibrium atomic physics model used in our computations, have been compared to emissivities obtained from different other models. These comparisons provide an attractive way to explain the discrepancies between experimental and calculated quantitative results.

Peracetic acid-ionic liquid pretreatment to enhance enzymatic saccharification of lignocellulosic biomass.

PubMed

Uju; Abe, Kojiro; Uemura, Nobuyuki; Oshima, Toyoji; Goto, Masahiro; Kamiya, Noriho

2013-06-01

To enhance enzymatic saccharification of pine biomass, the pretreatment reagents peracetic acid (PAA) and ionic liquid (IL) were validated in single reagent pretreatments or combination pretreatments with different sequences. In a 1h saccharification, 5-25% cellulose conversion was obtained from the single pretreatment of PAA or IL. In contrast, a marked enhancement in conversion rates was achieved by PAA-IL combination pretreatments (45-70%). The PAA followed by IL (PAA+IL) pretreatment sequence was the most effective for preparing an enzymatic digestible regenerated biomass with 250-fold higher glucose formation rates than untreated biomass and 2- to 12-fold higher than single pretreatments with PAA or IL alone. Structural analysis confirmed that this pretreatment resulted in biomass with highly porous structural fibers associated with the reduction of lignin content and acetyl groups. Using the PAA+IL sequence, biomass loading in the pretreatment step can be increased from 5% to 15% without significant decrease in cellulose conversion. Copyright © 2013 Elsevier Ltd. All rights reserved.

Estimating Effective Dose of Radiation From Pediatric Cardiac CT Angiography Using a 64-MDCT Scanner: New Conversion Factors Relating Dose-Length Product to Effective Dose.

PubMed

Trattner, Sigal; Chelliah, Anjali; Prinsen, Peter; Ruzal-Shapiro, Carrie B; Xu, Yanping; Jambawalikar, Sachin; Amurao, Maxwell; Einstein, Andrew J

2017-03-01

The purpose of this study is to determine the conversion factors that enable accurate estimation of the effective dose (ED) used for cardiac 64-MDCT angiography performed for children. Anthropomorphic phantoms representative of 1- and 10-year-old children, with 50 metal oxide semiconductor field-effect transistor dosimeters placed in organs, underwent scanning performed using a 64-MDCT scanner with different routine clinical cardiac scan modes and x-ray tube potentials. Organ doses were used to calculate the ED on the basis of weighting factors published in 1991 in International Commission on Radiological Protection (ICRP) publication 60 and in 2007 in ICRP publication 103. The EDs and the scanner-reported dose-length products were used to determine conversion factors for each scan mode. The effect of infant heart rate on the ED and the conversion factors was also assessed. The mean conversion factors calculated using the current definition of ED that appeared in ICRP publication 103 were as follows: 0.099 mSv · mGy -1 · cm -1 , for the 1-year-old phantom, and 0.049 mSv · mGy -1 · cm -1 , for the 10-year-old phantom. These conversion factors were a mean of 37% higher than the corresponding conversion factors calculated using the older definition of ED that appeared in ICRP publication 60. Varying the heart rate did not influence the ED or the conversion factors. Conversion factors determined using the definition of ED in ICRP publication 103 and cardiac, rather than chest, scan coverage suggest that the radiation doses that children receive from cardiac CT performed using a contemporary 64-MDCT scanner are higher than the radiation doses previously reported when older chest conversion factors were used. Additional up-to-date pediatric cardiac CT conversion factors are required for use with other contemporary CT scanners and patients of different age ranges.

Vitamin C supplementation improve the sputum conversion culture rate in pulmonary tuberculosis treatment while rifampicin susceptible

NASA Astrophysics Data System (ADS)

Susanto, L.; Siregar, Y.; Kusumawati, L.

2018-03-01

The failure of first-line tuberculosis treatment greatly affects multiple drug-resistant tuberculosis. In vitro study of vitamin C induces the death of M. tuberculosis bacteria and accelerates healing of tuberculosis, so the multiple drug-resistant tuberculosis can be avoided. This research aimed to identify the effect of vitamin C as a supportive treatment on the sputum conversion rate. The randomizedand double group with a parallel design by matching pair method was used to collect samples. The first group was treated with standard tuberculosis treatment, and the other was given vitamin C supplementation. Vitamin C plasma level analyzation was performed before and after two months of treatment. Sputum conversion was evaluated every week for eight weeks. The comparison of vitamin C plasma level in pre and post-treatment group was significant (p=0.03) but not in the other group. There was no significant difference in vitamin C plasma level between two groups (p=0.21). The proportion of sputum conversion rate in both group in the first week was 0% vs. 9.6% (p=0.83) and the last week of study was 83.9% vs. 100% (p=0.02). In conclusion, vitamin C supplementation has effects in improving the healing process of tuberculosis patients as indicated by higher in sputum conversion rate.

Shape-Controlled Synthesis of High-Quality Cu7 S4 Nanocrystals for Efficient Light-Induced Water Evaporation.

PubMed

Zhang, Changbo; Yan, Cong; Xue, Zhenjie; Yu, Wei; Xie, Yinde; Wang, Tie

2016-10-01

Copper sulfides (Cu 2-x S), are a novel kind of photothermal material exhibiting significant photothermal conversion efficiency, making them very attractive in various energy conversion related devices. Preparing high quality uniform Cu 2-x S nanocrystals (NCs) is a top priority for further energy-and sustainability relevant nanodevices. Here, a shape-controlled high quality Cu 7 S 4 NCs synthesis strategy is reported using sulfur in 1-octadecene as precursor by varying the heating temperature, as well as its forming mechanism. The performance of the Cu 7 S 4 NCs is further explored for light-driven water evaporation without the need of heating the bulk liquid to the boiling point, and the results suggest that as-synthesized highly monodisperse NCs perform higher evaporation rate than polydisperse NCs under the identical morphology. Furthermore, disk-like NCs exhibit higher water evaporation rate than spherical NCs. The water evaporation rate can be further enhanced by assembling the organic phase Cu 7 S 4 NCs into a dense film on the aqueous solution surface. The maximum photothermal conversion efficiency is as high as 77.1%. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Risk factors associated with conversion of laparoscopic simple closure in perforated duodenal ulcer.

PubMed

Kim, Ji-Hyun; Chin, Hyung-Min; Bae, You-Jin; Jun, Kyong-Hwa

2015-03-01

Precise patient selection criteria are necessary to guide the surgeon in selecting laparoscopic repair for patients with perforated peptic ulcers. The aims of this study are to report surgical outcomes after surgery for perforated duodenal ulcers and identify risk factors for predicting failure of laparoscopic simple closure for perforated duodenal ulcer. In total, 77 patients who underwent laparoscopic simple closure for perforated duodenal ulcers from January 2007 to September 2013 were retrospectively analyzed. Patients were divided into totally laparoscopic and conversion groups. The characteristics of patients, intraoperative findings, postoperative complications, conversion rates and suture leakage rates of each group were investigated. Laparoscopic repair was completed in 69 (89.6%) of 77 patients, while 8 (10.4%) underwent conversion to open repair. Patients in the conversion group had longer perforation time, larger perforation size, more suture leakage, longer hospital stay, and higher 30-day mortality rate than those in the totally laparoscopic group. The size of perforation was the only risk factor for conversion in multivariable analysis. Patients with an ulcer perforation size of ≥9 mm or with perforation duration of ≥12.5 h had a significantly increased risk for conversion and suture leakage. Ulcer size of ≥9 mm is a significant risk factor for predicting conversion in laparoscopic simple closure. Suture leakage is associated with ulcer size (9 mm) and duration of perforation (12.5 h). Copyright © 2015 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.

Leveraging Distant Relatedness to Quantify Human Mutation and Gene-Conversion Rates

PubMed Central

Palamara, Pier Francesco; Francioli, Laurent C.; Wilton, Peter R.; Genovese, Giulio; Gusev, Alexander; Finucane, Hilary K.; Sankararaman, Sriram; Sunyaev, Shamil R.; de Bakker, Paul I.W.; Wakeley, John; Pe’er, Itsik; Price, Alkes L.

2015-01-01

The rate at which human genomes mutate is a central biological parameter that has many implications for our ability to understand demographic and evolutionary phenomena. We present a method for inferring mutation and gene-conversion rates by using the number of sequence differences observed in identical-by-descent (IBD) segments together with a reconstructed model of recent population-size history. This approach is robust to, and can quantify, the presence of substantial genotyping error, as validated in coalescent simulations. We applied the method to 498 trio-phased sequenced Dutch individuals and inferred a point mutation rate of 1.66 × 10−8 per base per generation and a rate of 1.26 × 10−9 for <20 bp indels. By quantifying how estimates varied as a function of allele frequency, we inferred the probability that a site is involved in non-crossover gene conversion as 5.99 × 10−6. We found that recombination does not have observable mutagenic effects after gene conversion is accounted for and that local gene-conversion rates reflect recombination rates. We detected a strong enrichment of recent deleterious variation among mismatching variants found within IBD regions and observed summary statistics of local sharing of IBD segments to closely match previously proposed metrics of background selection; however, we found no significant effects of selection on our mutation-rate estimates. We detected no evidence of strong variation of mutation rates in a number of genomic annotations obtained from several recent studies. Our analysis suggests that a mutation-rate estimate higher than that reported by recent pedigree-based studies should be adopted in the context of DNA-based demographic reconstruction. PMID:26581902

T-SPOT.TB Interferon-γ Release Assay Performance in Healthcare Worker Screening at Nineteen U.S. Hospitals.

PubMed

King, Thomas C; Upfal, Mark; Gottlieb, Andrew; Adamo, Philip; Bernacki, Edward; Kadlecek, Chris P; Jones, Jeffrey G; Humphrey-Carothers, Frances; Rielly, Albert F; Drewry, Pamela; Murray, Kathy; DeWitt, Marcie; Matsubara, Janet; O'Dea, Louis; Balser, John; Wrighton-Smith, Peter

2015-08-01

Interferon-γ release assays have significant advantages over tuberculin skin testing in many clinical situations. However, recent studies have called into question their reliability in serial testing of healthcare workers because of reportedly high rates of positivity and high conversion/reversion rates on retesting. To define the performance characteristics of the T-SPOT.TB test, an interferon-γ release assay, during serial screening programs of healthcare workers at 19 U.S. hospitals. A total of 42,155 T-SPOT.TB test results from healthcare workers at 19 geographically diverse hospitals obtained for routine tuberculosis screening programs were analyzed to determine the rates of positivity, reversion, and conversion in serial testing data. In 19,630 evaluable serial pairs from 16,076 healthcare workers, the mean test positivity rate was 2.3% (range, 0.0-27.4%). The mean conversion rate was 0.8% (range, 0.0-2.5%), and the mean reversion rate was 17.6%. Positivity and conversion rates correlated with known tuberculosis risk factors including age and sex. The observed specificity of the T-SPOT.TB test was at least 98.6%. The high concordance and test completion rates in this study suggest that the T-SPOT.TB test is a reliable tool for healthcare worker serial screening. As expected, the observed positivity rates were lower compared with the tuberculin skin test, likely reflecting the higher specificity of this test. Furthermore, the observed rates of conversion were low and significantly correlated with the geographic incidence of tuberculosis. Our findings suggest that the T-SPOT.TB test is an accurate and reliable way to screen healthcare workers.

Conversion to dementia in mild cognitive impairment diagnosed with DSM-5 criteria and with Petersen's criteria.

PubMed

Marcos, G; Santabárbara, J; Lopez-Anton, R; De-la-Cámara, C; Gracia-García, P; Lobo, E; Pírez, G; Menchón, J M; Palomo, T; Stephan, B C M; Brayne, C; Lobo, A

2016-05-01

In a background of revision of criteria for states of increased risk for progression to dementia, we compare the conversion rate to dementia and Alzheimer's disease (AD) of mild cognitive impairment (MCI) as diagnosed using DSM-5 (DSM-5-MCI) and Petersen's (P-MCI) criteria. A population representative cohort of 4057 dementia-free individuals 55+ years of age was followed up at 2.5 and 4.5 years in Zaragoza, Spain (ZARADEMP). Using the Geriatric Mental State- AGECAT for assessment, research psychiatrists diagnosed DSM-5-MCI and P-MCI following operationalized criteria. 'Conversion rate' (CR), 'annual conversion rate' (ACR), and incidence rate (IR) were calculated along with incidence rate ratio (IRR) to compare the performance of the intermediate cognitive definitions. At 4.5-year follow-up, in individuals aged 65+ years, ACRs for non-cases, P-MCI, and DSM-5-MCI were 0.8, 1.9 and 3.4, respectively, for global dementia. The IRRs were 2.9 and 5.3 for P-MCI and DSM5-MCI, respectively, being the non-cases the reference category. The corresponding values were slightly lower for AD. Conversion rate to dementia and AD was higher using DSM-5-MCI criteria than using Petersen's criteria. However, prediction of the construct still has some way to go, as most MCI individuals did not convert at 4.5-year follow-up. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Temperature and Atomic Oxygen Effects on Helium Leak Rates of a Candidate Main Interface Seal

NASA Technical Reports Server (NTRS)

Penney, Nicholas; Wasowski, Janice L.; Daniels, Christopher C.

2011-01-01

Helium leak tests were completed to characterize the leak rate of a 54 in. diameter composite space docking seal design in support of the National Aeronautics and Space Administration s (NASA's) Low Impact Docking System (LIDS). The evaluated seal design was a candidate for the main interface seal on the LIDS, which would be compressed between two vehicles, while docked, to prevent the escape of breathable air from the vehicles and into the vacuum of space. Leak tests completed at nominal temperatures of -30, 20, and 50 C on untreated and atomic oxygen (AO) exposed test samples were examined to determine the influence of both test temperature and AO exposure on the performance of the composite seal assembly. Results obtained for untreated seal samples showed leak rates which increased with increased test temperature. This general trend was not observed in tests of the AO exposed specimens. Initial examination of collected test data suggested that AO exposure resulted in higher helium leak rates, however, further analysis showed that the differences observed in the 20 and 50 C tests between the untreated and AO exposed samples were within the experimental error of the test method. Lack of discernable trends in the test data prevented concrete conclusions about the effects of test temperature and AO exposure on helium leak rates of the candidate seal design from being drawn. To facilitate a comparison of the current test data with results from previous leak tests using air as the test fluid, helium leak rates were converted to air leak rates using standard conversion factors for viscous and molecular flow. Flow rates calculated using the viscous flow conversion factor were significantly higher than the experimental air leakage values, whereas values calculated using the molecular flow conversion factor were significantly lower than the experimentally obtained air leak rates. The difference in these sets of converted flow rates and their deviation from the experimentally obtained air leak rate data suggest that neither conversion factor can be used alone to accurately convert helium leak rates to equivalent air leak rates for the test seals evaluated in this study; other leak phenomena, including permeation, must also be considered.

Predictive models for conversion of prediabetes to diabetes.

PubMed

Yokota, N; Miyakoshi, T; Sato, Y; Nakasone, Y; Yamashita, K; Imai, T; Hirabayashi, K; Koike, H; Yamauchi, K; Aizawa, T

2017-08-01

To clarify the natural course of prediabetes and develop predictive models for conversion to diabetes. A retrospective longitudinal study of 2105 adults with prediabetes was carried out with a mean observation period of 4.7years. Models were developed using multivariate logistic regression analysis and verified by 10-fold cross-validation. The relationship between [final BMI minus baseline BMI] (δBMI) and incident diabetes was analyzed post hoc by comparing the diabetes conversion rate for low (< -0.31kg/m 2 ) and high δBMI (≥ -0.31kg/m 2 ) subjects after matching the two groups for the covariates. Diabetes developed in 252 (2.5%/year), and positive family history, male sex, higher systolic blood pressure, plasma glucose (fasting and 1h- and 2h-values during 75g OGTT), hemoglobin A1c (HbA1c) and alanine aminotransferase were significant, independent predictors for the conversion. By using a risk score (RS) that took account of all these variables, incident diabetes was predicted with an area under the ROC curve (95% CI) of 0.80 (0.70-0.87) and a specificity of prediction of 61.8% at 80% sensitivity. On division of the participants into high- (n=248), intermediate- (n=336) and low-risk (n=1521) populations, the conversion rates were 40.1%, 18.5% and 5.9%, respectively. The conversion rate was lower in subjects with low than high δBMI (9.2% vs 14.4%, p=0.003). Prediabetes conversion to diabetes could be predicted with accuracy, and weight reduction during the observation was associated with lowered conversion rate. Copyright © 2017 Elsevier Inc. All rights reserved.

Modeling of the reactant conversion rate in a turbulent shear flow

NASA Technical Reports Server (NTRS)

Frankel, S. H.; Madnia, C. K.; Givi, P.

1992-01-01

Results are presented of direct numerical simulations (DNS) of spatially developing shear flows under the influence of infinitely fast chemical reactions of the type A + B yields Products. The simulation results are used to construct the compositional structure of the scalar field in a statistical manner. The results of this statistical analysis indicate that the use of a Beta density for the probability density function (PDF) of an appropriate Shvab-Zeldovich mixture fraction provides a very good estimate of the limiting bounds of the reactant conversion rate within the shear layer. This provides a strong justification for the implementation of this density in practical modeling of non-homogeneous turbulent reacting flows. However, the validity of the model cannot be generalized for predictions of higher order statistical quantities. A closed form analytical expression is presented for predicting the maximum rate of reactant conversion in non-homogeneous reacting turbulence.

The Effects of Cell Phone Conversations on the Attention and Memory of Bystanders

PubMed Central

Galván, Veronica V.; Vessal, Rosa S.; Golley, Matthew T.

2013-01-01

The pervasive use of cell phones impacts many people–both cell phone users and bystanders exposed to conversations. This study examined the effects of overhearing a one-sided (cell phone) conversation versus a two-sided conversation on attention and memory. In our realistic design, participants were led to believe they were participating in a study examining the relationship between anagrams and reading comprehension. While the participant was completing an anagram task, the researcher left the room and participants overheard a scripted conversation, either two confederates talking with each other or one confederate talking on a cell phone. Upon the researcher’s return, the participant took a recognition memory task with words from the conversation, and completed a questionnaire measuring the distracting nature of the conversation. Participants who overheard the one-sided conversation rated the conversation as significantly higher in distractibility than those who overheard the two-sided conversation. Also, participants in the one-sided condition scored higher on the recognition task. In particular they were more confident and accurate in their responses to words from the conversation than participants in the two-sided condition. However, participants’ scores on the anagram task were not significantly different between conditions. As in real world situations, individual participants could pay varying amounts of attention to the conversation since they were not explicitly instructed to ignore it. Even though the conversation was irrelevant to the anagram task and contained less words and noise, one-sided conversations still impacted participants’ self-reported distractibility and memory, thus showing people are more attentive to cell phone conversations than two-sided conversations. Cell phone conversations may be a common source of distraction causing negative consequences in workplace environments and other public places. PMID:23516514

The effects of cell phone conversations on the attention and memory of bystanders.

PubMed

Galván, Veronica V; Vessal, Rosa S; Golley, Matthew T

2013-01-01

The pervasive use of cell phones impacts many people-both cell phone users and bystanders exposed to conversations. This study examined the effects of overhearing a one-sided (cell phone) conversation versus a two-sided conversation on attention and memory. In our realistic design, participants were led to believe they were participating in a study examining the relationship between anagrams and reading comprehension. While the participant was completing an anagram task, the researcher left the room and participants overheard a scripted conversation, either two confederates talking with each other or one confederate talking on a cell phone. Upon the researcher's return, the participant took a recognition memory task with words from the conversation, and completed a questionnaire measuring the distracting nature of the conversation. Participants who overheard the one-sided conversation rated the conversation as significantly higher in distractibility than those who overheard the two-sided conversation. Also, participants in the one-sided condition scored higher on the recognition task. In particular they were more confident and accurate in their responses to words from the conversation than participants in the two-sided condition. However, participants' scores on the anagram task were not significantly different between conditions. As in real world situations, individual participants could pay varying amounts of attention to the conversation since they were not explicitly instructed to ignore it. Even though the conversation was irrelevant to the anagram task and contained less words and noise, one-sided conversations still impacted participants' self-reported distractibility and memory, thus showing people are more attentive to cell phone conversations than two-sided conversations. Cell phone conversations may be a common source of distraction causing negative consequences in workplace environments and other public places.

Enhancement and inhibition of light tunneling mediated by resonant mode conversion.

PubMed

Kartashov, Yaroslav V; Vysloukh, Victor A; Torner, Lluis

2014-02-15

We show that the rate at which light tunnels between neighboring multimode waveguides can be drastically increased or reduced by the presence of small longitudinal periodic modulations of the waveguide properties that stimulate resonant conversion between the eigenmodes of each waveguide. Such a conversion, available only in multimode guiding structures, leads to periodic power transfer into higher-order modes, whose tails may considerably overlap with neighboring waveguides. As a result, the effective coupling constant for neighboring waveguides may change by several orders of magnitude upon small variations in the longitudinal modulation parameters.

Long-Term Climate Implications of Persistent Loss of Tropical Peat Carbon Following Land Use Conversion

NASA Astrophysics Data System (ADS)

Frolking, S. E.; Dommain, R.; Glaser, P. H.; Joos, F.; Jeltsch-Thommes, A.

2016-12-01

The climate mitigation potential of tropical peatlands has gained increased attention as Southeast Asian tropical peat swamp forests are being deforested, drained and burned at very high rates, causing globally significant carbon dioxide (CO2) emissions to the atmosphere. We used a simple force-restore model to represent the perturbation to the atmospheric CO2 and CH4 burdens, and net radiative forcing, resulting from long-term conversion of tropical peat swamp forests to oil palm or acacia plantations. Drainage ditches are installed in land-use conversion to both oil palm and acacia, leading to a persistent change in the system greenhouse gas balance with the atmosphere. Drainage causes the net CO2 exchange to switch from a weak sink (removal from the atmosphere) in the accumulating peat of a swamp forest to a relatively strong source as the peat is oxidized. CH4 emissions increase due to relatively high emissions from the ditches themselves. For these systems, persistent CO2 fluxes have a much stronger impact on atmospheric radiative forcing than do the CH4 fluxes. Prior to conversion, slow peat accumulation (net CO2 uptake) over millennia establishes a slowly increasing net radiative cooling perturbation to the atmosphere. Upon conversion, CO2 loss rates are 16-32 times higher than pre-conversion CO2 uptake rates. Rapid loss rates cause the net radiative forcing perturbation to quickly (decades) become a net warming, which can persist for many centuries after the peat has all been oxidized.

A kinetic study of pyrolysis and combustion of microalgae Chlorella vulgaris using thermo-gravimetric analysis.

PubMed

Agrawal, Ankit; Chakraborty, Saikat

2013-01-01

This work uses thermo-gravimetric, differential thermo-gravimetric and differential thermal analyses to evaluate the kinetics of pyrolysis (in inert/N(2) atmosphere) and (oxidative) combustion of microalgae Chlorella vulgaris by heating from 50 to 800 °C at heating rates of 5-40 °C/min. This study shows that combustion produces higher biomass conversion than pyrolysis, and that three stages of decomposition occur in both cases, of which, the second one--consisting of two temperature zones--is the main stage of devolatization. Proteins and carbohydrates are decomposed in the first of the two zones at activation energies of 51 and 45 kJ/mol for pyrolysis and combustion, respectively, while lipids are decomposed in its second zone at higher activation energies of 64 and 63 kJ/mol, respectively. The kinetic expressions of the reaction rates in the two zones for pyrolysis and combustion have been obtained and it has been shown that increased heating rates result in faster and higher conversion. Copyright © 2012 Elsevier Ltd. All rights reserved.

Transient desorption of water vapor - A potential source of error in upper atmosphere rocket experiments

NASA Technical Reports Server (NTRS)

Kendall, B. R. F.; Weeks, J. O.

1974-01-01

Results of measurements of the outgassing rates of samples of materials and surface finishes used on the outer skins of rocket-borne experiment packages in simulated rocket ascents. The results showed outgassing rates for anodized aluminum in the second minute of flight which are two to three orders of magnitude higher than those given in typical tables of outgassing rates. The measured rates for aluminum with chromate conversion surface coatings were also abnormally high. These abnormally high initial rates fell quickly after about five to ten minutes to values comparable with those in the published literature. It is concluded that anodized and chromate conversion coatings on the aluminum outer surfaces of a sounding rocket experiment package will cause gross distortion of the true water vapor environment.

Management strategies, early results, benefits, and risk factors of laparoscopic repair of perforated peptic ulcer.

PubMed

Lunevicius, Raimundas; Morkevicius, Matas

2005-10-01

The primary goal of this study was to describe epidemiology and management strategies of the perforated duodenal ulcer, as well as the most common methods of laparoscopic perforated duodenal ulcer repair. The secondary goal was to demonstrate the value of prospective and retrospective studies regarding the early results of surgery and the risk factors. The tertiary goal was to emphasize the benefits of this operation, and the fourth goal was to clarify the possible risk factors associated with laparoscopic repair of the duodenal ulcer. The Medline/Pubmed database was used. Review was done after evaluation of 96 retrieved full-text articles. Thirteen prospective and twelve retrospective studies were selected, grouped, and summarized. The spectrum of the retrospective studies' results are as follows: median overall morbidity rate 10.5 %, median conversion rate 7%, median hospital stay 7 days, and median postoperative mortality rate 0%. The following is the spectrum of results of the prospective studies: median overall morbidity rate was slightly less (6%); the median conversion rate was higher (15%); the median hospital stay was shorter (5 days) and the postoperative mortality was higher (3%). The risk factors identified were the same. Shock, delayed presentation (> 24 hours), confounding medical condition, age > 70 years, poor laparoscopic expertise, ASA III-IV, and Boey score should be considered preoperative laparoscopic repair risk factors. Each of these factors independently should qualify as a criterion for open repair due to higher intraoperative risks as well as postoperative morbidity. Inadequate ulcer localization, large perforation size (defined by some as > 6 mm diameter, and by others as > 10 mm), and ulcers with friable edges are also considered as conversion risk factors.

Analytics to Action: Predictive Model Outcomes and a Communication Strategy for Student Persistence

ERIC Educational Resources Information Center

Miller, Nathan Brad; Bell, Bryan

2016-01-01

Increased federal attention to student completion metrics and uncertain financial forecasts have heightened the tenor of student retention conversations. Improved institutional retention rates will lead to higher completion rates and relieve some funding concerns. To accomplish these improvements, institutions have invested in analytics to better…

The analysis of 146 patients with difficult laparoscopic cholecystectomy.

PubMed

Bat, Orhan

2015-01-01

Laparoscopic cholecystectomy (LC) is very commonly performed surgical intervention. Acute or chronic cholecystitis, adhesions due to previous upper abdomen surgeries, Mirrizi's syndrome and obesity are common clinical conditions that can be associated with difficult cholecystectomy. In this study, we evaluated and scored the patients with difficult surgical exploration during laparoscopic cholecystectomy. All patients who underwent LC from 2010 to 2015 were retrospectively rewieved. According to intraoperative findings DLC cases were described and classified. Class I difficulty: Adhesion of omentum majus, transverse colon, duodenum to the fundus of the gallbladder. Class II difficulty: Adhesions in Calot's triangle and difficulty in dissection of cystic artery and cystic duct Class III difficulty: Difficulty in dissection of gallbladder bed (scleroathrophic gallbladder, hemorrhage from liver during dissection of gallbladder, chirotic liver). Class IV difficulty: Difficulty in exploration of gallbladder due to intraabdominal adhesions including technical problems. A total of 146 patients were operated with DLC. The most common difficulty type was Class I difficulty (88 patients/60.2%). Laparoscopic cholecystectomy was converted to laparotomy in 98 patients. Operation time was found to be related with conversion to open surgery (P<0.05). Wound infection rate was also statistically higher in conversion group (P<0.05). The opertion time was found to be longest with Class II difficulty. Conversion rate to open surgery was also highest with Class II difficulty group. Class II difficulty characterized by severe adhesions in calot's triangle is most serious problem among all DLC cases. They have longer operation time and higher conversion rate.

Predictors of delayed culture conversion among Ugandan patients.

PubMed

Atwine, Daniel; Orikiriza, Patrick; Taremwa, Ivan; Ayebare, Arnold; Logoose, Suzan; Mwanga-Amumpaire, Juliet; Jindani, Amina; Bonnet, Maryline

2017-04-24

Estimates of month-2 culture conversion, a proxy indicator of tuberculosis (TB) treatment efficacy in phase-2 trials can vary by culture-type and geographically with lower rates reported among African sites. The sub-study aimed at comparing TB detection rates of different culture media, within and across rifampicin-based regimens (R10, 15 and 20 mg/Kg) over a 6-month treatment follow-up period, and to establish predictors of month-2 culture non-conversion among HIV-negative TB patients enrolled at RIFATOX trial site in Uganda. Unlike in other Rifatox Trial sites, it is only in Uganda were Lowenstein-Jensen (LJ) and Mycobacteria growth indicator tube (MGIT) were used throughout 6-months for treatment monitoring. Conversion rates were compared at month-2, 4 and 6 across cultures and treatment-type. Binomial regression analysis performed for predictors of month-2 non-conversion. Of the 100 enrolled patients, 45% had converted based on combined LJ and MGIT by month-2, with no significant differences across treatment arms, p = 0.721. LJ exhibited higher conversion rates than MGIT at month-2 (58.4% vs 56.0%, p = 0.0707) and month-4 (98.9% vs 88.4%, p = 0.0391) respectively, more so within the high-dose rifampicin arms. All patients had converted by month-6. Time-to-TB detection (TTD) on MGIT and social service jobs independently predict month-2 non-conversion. The month-2 culture conversion used in phase 2 clinical trials as surrogate marker of treatment efficacy is influenced by the culture method used for monitoring mycobacterial response to TB treatment. Therefore, multi-centric TB therapeutic trials using early efficacy endpoint should use the same culture method across sites. The Time-to-detection of MTB on MGIT prior to treatment and working in Social service jobs bear an increased risk of culture non-conversion at month-2. ISRCTN ISRCTN55670677 . Registered 09th November 2010. Retrospectively registered.

Synthesis of Biodiesel in Batch and Packed-Bed Reactors Using Powdered and Granular Sugar Catalyst

NASA Astrophysics Data System (ADS)

Janaun, J.; Lim, P. M.; Balan, W. S.; Yaser, A. Z.; Chong, K. P.

2017-06-01

Increasing world production of palm oil warrants effective utilization of its waste. In particular, conversion of waste cooking oil into biodiesel has obtained global interest because of renewable energy need and reduction of CO2 emission. In this study, oleic acid used as a model compound for waste cooking oil conversion using esterification reaction catalysed by sugar catalyst (SC) in powdered (P-SC) and granular (G-SC) forms. The catalysts were synthesized via incomplete carbonization of D-glucose followed by functionalization with concentrated sulphuric acid. Catalysts characterizations were done for their physical and chemical properties using modern tools. Batch and packed-bed reactor systems were used to evaluate the reactivity of the catalysts. The results showed that G-SC had slightly higher total acidity and more porous than P-SC. The experimental conditions for batch reaction were temperature of 60°C, molar ratio of 1:20 (Oleic Acid:Methanol) and 2 wt. catalyst with respect to oleic acid. The results showed the maximum oleic acid conversion using G-SC and P-SC were 52 and 48, respectively. Whereas, the continuous reaction with varying feed flow rate as a function of retention time was studied by using 3 g of P-SC in 60 °C and 1:20 molar ratio in a packed-bed reactor. The results showed that a longer retention time which was 6.48 min and feed flow rate 1.38 ml/min, achieved higher average conversion of 9.9 and decreased with further increasing flow rate. G-SC showed a better average conversion of 10.8 at lowest feed flow rate of 1.38 ml/min in continuous reaction experiments. In a broader perspective, large scale continuous biodiesel production is feasible using granular over powdered catalyst mainly due to it lower pressure drop.

Difference in C3-C4 metabolism underlies tradeoff between growth rate and biomass yield in Methylobacterium extorquens AM1.

PubMed

Fu, Yanfen; Beck, David A C; Lidstrom, Mary E

2016-07-19

Two variants of Methylobacterium extorquens AM1 demonstrated a trade-off between growth rate and biomass yield. In addition, growth rate and biomass yield were also affected by supplementation of growth medium with different amounts of cobalt. The metabolism changes relating to these growth phenomena as well as the trade-off were investigated in this study. (13)C metabolic flux analysis was used to generate a detailed central carbon metabolic flux map with both absolute and normalized flux values. The major differences between the two variants occurred at the formate node as well as within C3-C4 inter-conversion pathways. Higher relative fluxes through formyltetrahydrofolate ligase, phosphoenolpyruvate carboxylase, and malic enzyme led to higher biomass yield, while higher relative fluxes through pyruvate kinase and pyruvate dehydrogenase led to higher growth rate. These results were then tested by phenotypic studies on three mutants (null pyk, null pck mutant and null dme mutant) in both variants, which agreed with the model prediction. In this study, (13)C metabolic flux analysis for two strain variants of M. extorquens AM1 successfully identified metabolic pathways contributing to the trade-off between cell growth and biomass yield. Phenotypic analysis of mutants deficient in corresponding genes supported the conclusion that C3-C4 inter-conversion strategies were the major response to the trade-off.

Electrochemical enhancement of nitric oxide removal from simulated lean-burn engine exhaust via solid oxide fuel cells.

PubMed

Huang, Ta-Jen; Wu, Chung-Ying; Lin, Yu-Hsien

2011-07-01

A solid oxide fuel cell (SOFC) unit is constructed with Ni-YSZ as the anode, YSZ as the electrolyte, and La(0.6)Sr(0.4)CoO(3)-Ce(0.9)Gd(0.1)O(1.95) as the cathode. The SOFC operation is performed at 600 °C with a cathode gas simulating the lean-burn engine exhaust and at various fixed voltage, at open-circuit voltage, and with an inert gas flowing over the anode side, respectively. Electrochemical enhancement of NO decomposition occurs when an operating voltage is generated; higher O(2) concentration leads to higher enhancement. Smaller NO concentration results in larger NO conversion. Higher operating voltage and higher O(2) concentration can lead to both higher NO conversion and lower fuel consumption. The molar rate of the consumption of the anode fuel can be very much smaller than that of NO to N(2) conversion. This makes the anode fuel consumed in the SOFC-DeNO(x) process to be much less than the equivalent amount of ammonia consumed in the urea-based selective catalytic reduction process. Additionally, the NO conversion increases with the addition of propylene and SO(2) into the cathode gas. These are beneficial for the application of the SOFC-DeNO(x) technology on treating diesel and other lean-burn engine exhausts.

Adding moxifloxacin is associated with a shorter time to culture conversion in pulmonary tuberculosis.

PubMed

Wang, J-Y; Wang, J-T; Tsai, T-H; Hsu, C-L; Yu, C-J; Hsueh, P-R; Lee, L-N; Yang, P-C

2010-01-01

To investigate whether adding moxifloxacin (MXF) to the standard anti-tuberculosis regimen can shorten the time to sputum culture conversion in pulmonary tuberculosis (PTB). Adults with culture-positive PTB were divided into two treatment groups by their choice: standard regimen alone (HERZ group) and standard regimen plus daily 400 mg MXF in the first 2 months (MXF group). Sputum samples were collected thrice weekly in the first 8 weeks. The propensity score was calculated to estimate the conditional probability of entering the MXF group. Factors influencing time to culture conversion were investigated using Cox proportional hazards regression analysis stratified by propensity score. Sixty-two patients were enrolled in the MXF group and 88 in the HERZ group; respectively 51 and 72 completed the study. The regimen was modified before culture conversion in respectively 6 (12%) and 12 (16%; P = 0.47) patients, due to adverse effects. The time to culture conversion was shorter in the MXF group (HR 2.1, 95%CI 1.4-3.2). The culture conversion rate after 6 weeks of treatment was respectively 82% and 61% (P = 0.011, <0.05/4, calculated using the modified Bonferroni method). Adding MXF to the standard anti-tuberculosis regimen in the first 2 months was associated with a shorter time to culture conversion, a higher 6-week culture conversion rate and reduced transmission of tuberculosis.

High-Efficiency Artificial Photosynthesis Using a Novel Alkaline Membrane Cell

NASA Technical Reports Server (NTRS)

Narayan, Sri; Haines, Brennan; Blosiu, Julian; Marzwell, Neville

2009-01-01

A new cell designed to mimic the photosynthetic processes of plants to convert carbon dioxide into carbonaceous products and oxygen at high efficiency, has an improved configuration using a polymer membrane electrolyte and an alkaline medium. This increases efficiency of the artificial photosynthetic process, achieves high conversion rates, permits the use of inexpensive catalysts, and widens the range of products generated by this type of process. The alkaline membrane electrolyte allows for the continuous generation of sodium formate without the need for any additional separation system. The electrolyte type, pH, electrocatalyst type, and cell voltage were found to have a strong effect on the efficiency of conversion of carbon dioxide to formate. Indium electrodes were found to have higher conversion efficiency compared to lead. Bicarbonate electrolyte offers higher conversion efficiency and higher rates than water solutions saturated with carbon dioxide. pH values between 8 and 9 lead to the maximum values of efficiency. The operating cell voltage of 2.5 V, or higher, ensures conversion of the carbon dioxide to formate, although the hydrogen evolution reaction begins to compete strongly with the formate production reaction at higher cell voltages. Formate is produced at indium and lead electrodes at a conversion efficiency of 48 mg of CO2/kilojoule of energy input. This efficiency is about eight times that of natural photosynthesis in green plants. The electrochemical method of artificial photosynthesis is a promising approach for the conversion, separation and sequestration of carbon dioxide for confined environments as in space habitats, and also for carbon dioxide management in the terrestrial context. The heart of the reactor is a membrane cell fabricated from an alkaline polymer electrolyte membrane and catalyst- coated electrodes. This cell is assembled and held in compression in gold-plated hardware. The cathode side of the cell is supplied with carbon dioxide-saturated water or bicarbonate solution. The anode side of the cell is supplied with sodium hydroxide solution. The solutions are circulated past the electrodes in the electrochemical cell using pumps. A regulated power supply provides the electrical energy required for the reactions. Photovoltaic cells can be used to better mimic the photosynthetic reaction. The current flowing through the electrochemical cell, and the cell voltage, are monitored during experimentation. The products of the electrochemical reduction of carbon dioxide are allowed to accumulate in the cathode reservoir. Samples of the cathode solution are withdrawn for product analysis. Oxygen is generated on the anode side and is allowed to vent out of the reservoir.

Steam gasification of acid-hydrolysis biomass CAHR for clean syngas production.

PubMed

Chen, Guanyi; Yao, Jingang; Yang, Huijun; Yan, Beibei; Chen, Hong

2015-03-01

Main characteristics of gaseous product from steam gasification of acid-hydrolysis biomass CAHR have been investigated experimentally. The comparison in terms of evolution of syngas flow rate, syngas quality and apparent thermal efficiency was made between steam gasification and pyrolysis in the lab-scale apparatus. The aim of this study was to determine the effects of temperature and steam to CAHR ratio on gas quality, syngas yield and energy conversion. The results showed that syngas and energy yield were better with gasification compared to pyrolysis under identical thermal conditions. Both high gasification temperature and introduction of proper steam led to higher gas quality, higher syngas yield and higher energy conversion efficiency. However, excessive steam reduced hydrogen yield and energy conversion efficiency. The optimal value of S/B was found to be 3.3. The maximum value of energy ratio was 0.855 at 800°C with the optimal S/B value. Copyright © 2014 Elsevier Ltd. All rights reserved.

Considering the health care entity C corporation conversion to tax pass-through entity status.

PubMed

Reilly, Robert F

2012-01-01

The double taxation of C corporation income from operations and from the ultimate sale of its assets makes the C corporation an inefficient tax status for many health care entities. At the time of this writing, the changes in the federal tax law that are scheduled to take effect in 2013 will increase this level of double-taxation inefficiency. The owners of a C corporation practice can avoid the C corporation status tax inefficiency by converting the practice to either (1) S corporation status or (2) LLC status. The conversion of the health care C corporation to an S corporation may be accomplished without a current tax cost. However, the conversion of a health care C corporation to an LLC status can result in a current tax at both the corporation level and the shareholder level. Nonetheless, the current conversion tax cost may be less than the future tax cost (1) of operating the practice as a C corporation and incurring double taxation at what may be higher tax rates or (2) of incurring the higher tax cost (or reduced price) on the ultimate disposition of the practice assets and the attendant double taxation of the appreciation in the value of the practice assets. Since individual income tax rates on qualifying dividends from C corporations and on capital gains are currently at very low rates, this may be a good time for C corporation practice owners to consider the costs and benefits of a conversion to either S corporation status or LLC status. The practice owners should consult with their accounting, legal, and valuation advisors in order to consider all of the costs and benefits of a possible corporate tax status conversion. An estimation of both the costs and benefits of the corporate tax status conversion depends on the concluded fair market values of the medical practice, dental practice, or other health care entity assets. And, that practice asset appraisal should encompass all of the practice assets, both tangible assets and intangible assets.

CO2 conversion in non-thermal plasma and plasma/g-C3N4 catalyst hybrid processes

NASA Astrophysics Data System (ADS)

Lu, Na; Sun, Danfeng; Zhang, Chuke; Jiang, Nan; Shang, Kefeng; Bao, Xiaoding; Li, Jie; Wu, Yan

2018-03-01

Carbon dioxide conversion at atmosphere pressure and low temperature has been studied in a cylindrical dielectric barrier discharge (DBD) reactor. Pure CO2 feed flows to the discharge zone and typical filamentary discharges were obtained in each half-cycle of the applied voltage. The gas temperature increased with discharge time and discharge power, which was found to affect the CO2 decomposition deeply. As the DBD reactor was cooled to ambient temperature, both the conversion of CO2 and the CO yield were enhanced. Especially the energy efficiencies changed slightly with the increase of discharge power and were much higher in cooling condition comparing to those without cooling. At a discharge power of 40 W, the energy efficiency under cooling condition was approximately six times more than that without cooling. Gas flow rate was observed to affect CO2 conversion and 0.1 L min-1 was obtained as optimum gas flow rate under cooling condition. In addition, the CO2 conversion rate in plasma/g-C3N4 catalyst hybrid system was twice times as that in plasma-alone system. In case of cooling, the existence of g-C3N4 catalyst contributed to a 47% increase of CO2 conversion compared to the sole plasma process. The maximum energy-efficiency with g-C3N4 was 0.26 mmol kJ-1 at 20 W, which increased by 157% compared to that without g-C3N4. The synergistic effect of DBD plasma with g-C3N4 on pure CO2 conversion was verified.

The analysis of 146 patients with difficult laparoscopic cholecystectomy

PubMed Central

Bat, Orhan

2015-01-01

Introduction: Laparoscopic cholecystectomy (LC) is very commonly performed surgical intervention. Acute or chronic cholecystitis, adhesions due to previous upper abdomen surgeries, Mirrizi’s syndrome and obesity are common clinical conditions that can be associated with difficult cholecystectomy. In this study, we evaluated and scored the patients with difficult surgical exploration during laparoscopic cholecystectomy. Material and Method: All patients who underwent LC from 2010 to 2015 were retrospectively rewieved. According to intraoperative findings DLC cases were described and classified. Class I difficulty: Adhesion of omentum majus, transverse colon, duodenum to the fundus of the gallbladder. Class II difficulty: Adhesions in Calot’s triangle and difficulty in dissection of cystic artery and cystic duct Class III difficulty: Difficulty in dissection of gallbladder bed (scleroathrophic gallbladder, hemorrhage from liver during dissection of gallbladder, chirotic liver). Class IV difficulty: Difficulty in exploration of gallbladder due to intraabdominal adhesions including technical problems. Results: A total of 146 patients were operated with DLC. The most common difficulty type was Class I difficulty (88 patients/60.2%). Laparoscopic cholecystectomy was converted to laparotomy in 98 patients. Operation time was found to be related with conversion to open surgery (P<0.05). Wound infection rate was also statistically higher in conversion group (P<0.05). The opertion time was found to be longest with Class II difficulty. Conversion rate to open surgery was also highest with Class II difficulty group. Conclusion: Class II difficulty characterized by severe adhesions in calot’s triangle is most serious problem among all DLC cases. They have longer operation time and higher conversion rate. PMID:26629124

Publication outcomes for research presented at a Canadian surgical conference.

PubMed

Crawford, Sean A; Roche-Nagle, Graham

2017-04-01

The failure of investigators to publish research in peer-reviewed journals following acceptance at a national or international meeting can lead to significant publication biases in the literature. Our objective was to evaluate the abstract to manuscript conversion rate for abstracts presented at the Canadian Society for Vascular Surgery (CSVS) annual meeting and to evaluate the conversion rate for CSVS-awarded research grants. We searched for authors of abstracts accepted at the CSVS Annual Meeting (2007-2013) and recipients of CSVS research awards (2005-2013) on Scopus and PubMed databases to identify related publications. We identified 84 publications from 188 research abstracts (45%) and 17 publications from 39 research grants (44%). The mean time to publication was 1.8 years and the mean impact factor was 2.7. Studies related to endovascular therapies demonstrated a trend toward a higher rate of publication relative to open surgical therapies (64 [56%] v. 37 [27%]). Additionally, we observed a similar trend in research grant topics related to endovascular therapies relative to open surgical therapies (9 [67%] v. 8 [38%]). Finally, CSVS research grant recipients who subsequently published had a significantly higher h-index at the time of receipt than those who had not published. The CSVS annual meeting's abstract to publication conversion rate is comparable to that of its Canadian peers as well as to other medical specialties; however, a substantial publication gap remains. We identified several potential areas that may help to improve the effectiveness of CSVS research grants.

FOLFOXIRI Plus Bevacizumab as Conversion Therapy for Patients With Initially Unresectable Metastatic Colorectal Cancer: A Systematic Review and Pooled Analysis.

PubMed

Tomasello, Gianluca; Petrelli, Fausto; Ghidini, Michele; Russo, Alessandro; Passalacqua, Rodolfo; Barni, Sandro

2017-07-13

The combination of fluorouracil, oxaliplatin, and irinotecan plus bevacizumab (FOLFOXIRI-Bev) is an established and effective first-line chemotherapy regimen for metastatic colorectal cancer. However, resection rates of metastases and overall survival with this schedule have never been systematically evaluated in published studies including, but not limited to, the TRIBE (TRIplet plus BEvacizumab) trial. To assess the clinical efficacy of FOLFOXIRI-Bev, including outcomes and rates of surgical conversions. A systematic review was conducted in October 2016 in concordance with the PRISMA guidelines of PubMed, the Cochrane Central Register of Controlled Trials, SCOPUS, Web of Science, Google Scholar, CINAHL, Ovid, and EMBASE using the terms FOLFOXIRI and bevacizumab and (colorectal cancer). Clinical trials, retrospective case series, and prospective case series that used FOLFOXIRI-Bev for the treatment of initially unresectable metastatic colorectal cancer in humans were included. Individual case reports and retrospective case series with fewer than 10 patients were excluded. Data were extracted independently by 2 reviewers on a predesigned, standardized form. Ultimately, data were aggregated to obtain the pooled effect size of efficacy, according to the random-effects model and weighted for the number of patients included in each trial. Median overall survival and progression-free survival, overall response rates, and rates of R0 surgical conversions and overall surgical conversions. Eleven FOLFOXIRI-Bev studies published between 2010 and 2016 met the inclusion criteria and were pooled for analysis. The studies included 889 patients, with 877 patients clinically evaluable for overall response rates. The objective response rate to FOLFOXIRI-Bev was 69% (95% CI, 65%-72%; I2 = 25%). The rate of overall surgical conversions was 39.1% (95% CI, 26.9%-52.8%), and the rate of R0 surgical conversions was 28.1% (95% CI, 18.1%-40.8%). Median pooled overall survival was 30.2 months (95% CI, 26.5-33.7 months) in 6 trials with data available, and progression-free survival was 12.4 months (95% CI, 10.0-14.3 months) in 9 trials with data available. In meta-regression analysis, variables significantly associated with conversion surgery were disease limited to the liver and a higher median number of cycles (close to 12). For patients with surgically unresectable metastatic colorectal cancer, FOLFOXIRI-Bev is associated with a significant overall response rate. Such an effective regimen leads to a probability of surgical conversion of distant metastases approaching 40%, with more than one-fourth of patients having an R0 resection.

Efficient visible and UV generation by frequency conversion of a mode-filtered fiber amplifier

NASA Astrophysics Data System (ADS)

Kliner, Dahv A. V.; Di Teodoro, Fabio; Koplow, Jeffrey P.; Moore, Sean W.; Smith, Arlee V.

2003-07-01

We have generated the second, third, fourth, and fifth harmonics of the output of a Yb-doped fiber amplifier seeded by a passively Q-switched Nd:YAG microchip laser. The fiber amplifier employed multimode fiber (25 μm core diameter, V ~ 7.4) to provide high-peak-power pulses, but diffraction-limited beam quality was obtained by use of bend-loss-induced mode filtering. The amplifier output had a pulse duration of 0.97 ns and smooth, transform-limited temporal and spectral profiles (~500 MHz linewidth). We obtained high nonlinear conversion efficiencies using a simple optical arrangement and critically phase-matched crystals. Starting with 320 mW of average power at 1064 nm (86 ´J per pulse at a 3.7 kHz repetition rate), we generated 160 mW at 532 nm, 38 mW at 355 nm, 69 mW at 266 nm, and 18 mW at 213 nm. The experimental results are in excellent agreement with calculations. Significantly higher visible and UV powers will be possible by operating the fiber amplifier at higher repetition rates and pulse energies and by further optimizing the nonlinear conversion scheme.

Relevance and speed of message delivery trade-offs in augmentative and alternative communication.

PubMed

Bedrosian, Jan L; Hoag, Linda A; McCoy, Kathleen F

2003-08-01

This report is the first in a series of investigations designed to test a theory identifying the effects of conversational trade-offs between selected maxims on public attitudes toward augmentative and alternative communication (AAC) system users and their communication. In the current study, the trade-offs between the relevance of a prestored message and its speed of delivery were examined. Participating were 96 sales clerks. Twelve scripted videotaped conversational conditions, involving an AAC customer and a clerk at a checkout counter, were used to manipulate message relevance, speed of message delivery, and participant/AAC user gender. Following each assigned viewing, participants completed a questionnaire designed to assess their attitudes toward the AAC user and his or her communication. Significantly higher mean ratings were found for the conditions involving the slowly delivered relevant messages (both preceded by a conversational floorholder and without a floorholder) when compared to the quickly delivered partly relevant message condition. In addition, the condition involving the slowly delivered relevant message with a floorholder yielded significantly higher mean ratings than that without the floorholder. There was no effect for participant/user gender. Modifications of the theory and technological implications are discussed.

Substitution of ethambutol with linezolid during the intensive phase of treatment of pulmonary tuberculosis: study protocol for a prospective, multicenter, randomized, open-label, phase II trial.

PubMed

Lee, Ji Yeon; Kim, Deog Kyeom; Lee, Jung-Kyu; Yoon, Ho Il; Jeong, Ina; Heo, Eunyoung; Park, Young Sik; Lee, Jae Ho; Park, Sung Soo; Lee, Sang-Min; Lee, Chang-Hoon; Lee, Jinwoo; Choi, Sun Mi; Park, Jong Sun; Joh, Joon-Sung; Cho, Young-Jae; Lee, Yeon Joo; Kim, Se Joong; Hwang, Young Ran; Kim, Hyeonjeong; Ki, Jongeun; Choi, Hyungsook; Han, Jiyeon; Ahn, Heejung; Hahn, Seokyung; Yim, Jae-Joon

2017-02-13

Linezolid, an oxazolidinone, substantially improves treatment outcomes of multidrug-resistant tuberculosis and extensively drug-resistant tuberculosis. We started a trial to test whether the use of linezolid instead of ethambutol could increase the rate of sputum culture conversion as of 8 weeks of treatment in patients with drug-susceptible tuberculosis. This is a phase II, multicenter, randomized study with three arms. We are enrolling patients with pulmonary tuberculosis without rifampicin resistance screened by the Xpert MTB/RIF® assay. The standard treatment arm uses isoniazid (6 months), rifampicin (6 months), pyrazinamide (2 months), and ethambutol (2 months). Experimental arm 1 uses linezolid (600 mg/day) for 4 weeks instead of ethambutol. Experimental arm 2 uses linezolid (600 mg/day) for 2 weeks instead of ethambutol. The primary outcome is the sputum culture conversion rate on liquid media after 2 months of treatment. Secondary outcomes include the sputum culture conversion rate on solid media after 2 months of treatment, time to sputum culture conversion on liquid and solid media, cure rate, and treatment success rate. The frequencies of total adverse events (AEs) and serious AEs will be described and documented. Based on an α = 0.05 level of significance, a power of 85%, a 15% difference in the culture conversion rate after 2 months between the control arm and experimental arm 1 (75% vs. 90%), a 10% default (loss to follow-up) rate, and a 10% culture failure, the required number per arm was calculated to be 143 (429 in total). This trial will reveal the effectiveness and safety of 2 or 4 weeks of use of linezolid instead of ethambutol for patients with drug-susceptible pulmonary tuberculosis. If a new regimen including linezolid shows a higher culture conversion rate by week 8, and is safe, it could be tested as a 4-month antituberculosis treatment regimen in the future. ClincalTrials.gov, NCT01994460 . Registered on 13 November 2013.

Fischer-Tropsch synthesis in near-critical n-hexane: Pressure-tuning effects

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bochniak, D.J.; Subramaniam, B.

For Fe-catalyzed Fischer-Tropsch (FT) synthesis with near-critical n-hexane (P{sub c} = 29.7 bar; T{sub c} = 233.7 C) as the reaction medium, isothermal pressure tuning from 1.2--2.4 P{sub c} (for n-hexane) at the reaction temperature (240 C) significantly changes syngas conversion and product selectivity. For fixed feed rates of syngas (H{sub 2}/CO = 0.5; 50 std. cm{sup 3}/g catalyst) and n-hexane (1 mL/min), syngas conversion attains a steady state at all pressures, increasing roughly threefold in this pressure range. Effective rate constants, estimated assuming a first-order dependence of syngas conversion on hydrogen, reveal that the catalyst effectiveness increases with pressuremore » implying the alleviation of pore-diffusion limitations. Pore accessibilities increase at higher pressures because the extraction of heavier hydrocarbons from the catalyst pores is enhanced by the liquid-like densities, yet better-than-liquid transport properties, of n-hexane. This explanation is consistent with the single {alpha} (= 0.78) Anderson-Schulz-Flory product distribution, the constant chain termination probability, and the higher primary product (1-olefin) selectivities ({approximately}80%) observed at the higher pressures. Results indicate that the pressure tunability of the density and transport properties of near-critical reaction media offers a powerful tool to optimize catalyst activity and product selectivity during FT reactions on supported catalysts.« less

OPTN/SRTR 2012 Annual Data Report: deceased organ donation.

PubMed

Israni, A K; Zaun, D; Rosendale, J D; Snyder, J J; Kasiske, B L

2014-01-01

The status of deceased organ donation is assessed using several metrics, including donation/conversion rate (how often at least one organ is recovered for transplant from an eligible death), organ yield (ratio of observed/expected numbers of organs transplanted), and rate of organs discarded (number of organs discarded divided by the number of organs recovered for transplant). The 2012 donation/conversion rate was 72.5. eligible donors per 100 eligible deaths, slightly lower than the 2011 rate but higher than in previous years. The 2011-2012 yield ratio varied by donation service area from 0.91 (fewer organs transplanted per donor than expected) to 1.09 (more than expected), and also varied for specific organs. The mean number of organs transplanted per donor in 2012 was 3.02, lower than in 2011 and 2010; this number varied by donation service area from 2.04 to 3.76. The number of organs discarded is calculated by subtracting the number of organs transplanted from the number recovered for transplant; this number is used to calculate the discard rate. The discard rate in 2012 for all organs combined was 0.14 per recovered organ, slightly higher than in 2011 and 2011; it varied by donation service area and organ type. © Copyright 2013 The American Society of Transplantation and the American Society of Transplant Surgeons.

Effects of activity interference on annoyance due to aircraft noise

NASA Technical Reports Server (NTRS)

Willshire, K. F.; Powell, C. A.

1981-01-01

The effects of aircraft flyover noise on annoyance were compared for face to face conversation, reverie, and television viewing. Eighteen 5 minute sessions, each composed of three flyovers, were presented on each of 2 days to subjects in a simulated living room. Twelve pairs of females and 12 pairs of males were tested, once before and once after work. Flyovers varied in peak noise level from 53 to 83 dB, A weighted. On each day, subjects engaged in 18 sessions, six of conversation, six of television viewing, and six of reverie. The subjects completed subjective ratings of annoyance and acceptability following every session. Annoyance and unacceptability rating scores were significantly higher for the activity of television viewing compared to conversation or reverie. There was no difference between judgments during the latter two activities. No differences were found in the judgments when compared on the basis of "fatigue" (before/after work) or sex of the subject.

Difference in C3–C4 metabolism underlies tradeoff between growth rate and biomass yield in Methylobacterium extorquens AM1

DOE PAGES

Fu, Yanfen; Beck, David A. C.; Lidstrom, Mary E.

2016-07-19

In this study, two variants of Methylobacterium extorquens AM1 demonstrated a trade-off between growth rate and biomass yield. In addition, growth rate and biomass yield were also affected by supplementation of growth medium with different amounts of cobalt. The metabolism changes relating to these growth phenomena as well as the trade-off were investigated in this study. 13C metabolic flux analysis was used to generate a detailed central carbon metabolic flux map with both absolute and normalized flux values. As a result, the major differences between the two variants occurred at the formate node as well as within C3-C4 inter-conversion pathways.more » Higher relative fluxes through formyltetrahydrofolate ligase, phosphoenolpyruvate carboxylase, and malic enzyme led to higher biomass yield, while higher relative fluxes through pyruvate kinase and pyruvate dehydrogenase led to higher growth rate. These results were then tested by phenotypic studies on three mutants (null pyk, null pck mutant and null dme mutant) in both variants, which agreed with the model prediction. In this study, 13C metabolic flux analysis for two strain variants of M. extorquens AM1 successfully identified metabolic pathways contributing to the trade-off between cell growth and biomass yield. Phenotypic analysis of mutants deficient in corresponding genes supported the conclusion that C3-C4 inter-conversion strategies were the major response to the trade-off.« less

Difference in C3–C4 metabolism underlies tradeoff between growth rate and biomass yield in Methylobacterium extorquens AM1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fu, Yanfen; Beck, David A. C.; Lidstrom, Mary E.

In this study, two variants of Methylobacterium extorquens AM1 demonstrated a trade-off between growth rate and biomass yield. In addition, growth rate and biomass yield were also affected by supplementation of growth medium with different amounts of cobalt. The metabolism changes relating to these growth phenomena as well as the trade-off were investigated in this study. 13C metabolic flux analysis was used to generate a detailed central carbon metabolic flux map with both absolute and normalized flux values. As a result, the major differences between the two variants occurred at the formate node as well as within C3-C4 inter-conversion pathways.more » Higher relative fluxes through formyltetrahydrofolate ligase, phosphoenolpyruvate carboxylase, and malic enzyme led to higher biomass yield, while higher relative fluxes through pyruvate kinase and pyruvate dehydrogenase led to higher growth rate. These results were then tested by phenotypic studies on three mutants (null pyk, null pck mutant and null dme mutant) in both variants, which agreed with the model prediction. In this study, 13C metabolic flux analysis for two strain variants of M. extorquens AM1 successfully identified metabolic pathways contributing to the trade-off between cell growth and biomass yield. Phenotypic analysis of mutants deficient in corresponding genes supported the conclusion that C3-C4 inter-conversion strategies were the major response to the trade-off.« less

Herbicide treatment effects on properties of mountain big sagebrush soils after fourteen years

NASA Technical Reports Server (NTRS)

Burke, I. C.; Reiners, W. A.; Sturges, D. L.; Matson, P. A.

1987-01-01

The effects of sagebrush conversion on the soil properties of a high-elevation portion of the Western Intermountain Sagebrush Steppe (West, 1983) are described. Changes were found in only a few soil chemical properties after conversion to grassland. It was found that surface concentrations of N were lower under grass vegetation than under undisturbed vegetation. Undershrub net N mineralization rates were higher under shrubs in the sagebrush vegetation than under former shrubs in the grass vegetation.

Experimental demonstration of novel cascaded SFG+DFG wavelength conversion of picosecond pulses in LiNbO 3 waveguides

NASA Astrophysics Data System (ADS)

Wang, Jian; Sun, Junqiang; Luo, Chuanhong

2006-06-01

A novel cascaded χ (2) wavelength conversion of picosecond pulses based on sum frequency generation and difference frequency generation (SFG+DFG) is proposed and experimentally demonstrated in LiNbO 3 waveguides. The signal pulse with 40-GHz repetition rate and 1.57-ps pulse width is adopted. First of all, high conversion efficiency about -18.93dB can be achieved with low power level required for both two pump lights, which is greatly enhanced approximately 8dB compared with the conventional cascaded second-order nonlinear interactions (SHG+DFG) with a single and much higher power pump. Secondly, the wavelength of the converted idler wave can be tuned from 1527.4 to 1540.5nm when the signal wavelength is changed from 1561.9 to 1548.4nm, and about 13.1nm converted idler bandwidth is achieved with the conversion efficiency higher than -31dB. Thirdly, two pump wavelengths can be separated as large as 17.3nm. Meanwhile, when one pump wavelength is fixed at 1549.1nm, the other can be tuned within a wide wavelength range about 7.6nm with the conversion efficiency higher than -34dB, which is much larger than that in the SHG+DFG situation. Finally, the temporal waveform of the converted idler pulse is observed with rather clear appearance achieved, and no obvious changes of the pulse shape and width are found compared with its corresponding original injected signal, showing that our proposed scheme exhibits a very good conversion performance.

Estimating global "blue carbon" emissions from conversion and degradation of vegetated coastal ecosystems.

PubMed

Pendleton, Linwood; Donato, Daniel C; Murray, Brian C; Crooks, Stephen; Jenkins, W Aaron; Sifleet, Samantha; Craft, Christopher; Fourqurean, James W; Kauffman, J Boone; Marbà, Núria; Megonigal, Patrick; Pidgeon, Emily; Herr, Dorothee; Gordon, David; Baldera, Alexis

2012-01-01

Recent attention has focused on the high rates of annual carbon sequestration in vegetated coastal ecosystems--marshes, mangroves, and seagrasses--that may be lost with habitat destruction ('conversion'). Relatively unappreciated, however, is that conversion of these coastal ecosystems also impacts very large pools of previously-sequestered carbon. Residing mostly in sediments, this 'blue carbon' can be released to the atmosphere when these ecosystems are converted or degraded. Here we provide the first global estimates of this impact and evaluate its economic implications. Combining the best available data on global area, land-use conversion rates, and near-surface carbon stocks in each of the three ecosystems, using an uncertainty-propagation approach, we estimate that 0.15-1.02 Pg (billion tons) of carbon dioxide are being released annually, several times higher than previous estimates that account only for lost sequestration. These emissions are equivalent to 3-19% of those from deforestation globally, and result in economic damages of $US 6-42 billion annually. The largest sources of uncertainty in these estimates stems from limited certitude in global area and rates of land-use conversion, but research is also needed on the fates of ecosystem carbon upon conversion. Currently, carbon emissions from the conversion of vegetated coastal ecosystems are not included in emissions accounting or carbon market protocols, but this analysis suggests they may be disproportionally important to both. Although the relevant science supporting these initial estimates will need to be refined in coming years, it is clear that policies encouraging the sustainable management of coastal ecosystems could significantly reduce carbon emissions from the land-use sector, in addition to sustaining the well-recognized ecosystem services of coastal habitats.

78 FR 32375 - Magnuson-Stevens Act Provisions; General Provisions for Domestic Fisheries; Application for...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-30

... 02543-1026, or online at: www.nefsc.noaa.gov/nefsc/publications/ . The revised EFP would exempt vessels.... Category F vessels would be charged monkfish RSA DAS at a higher pro- rated rate of 2.909:1 RSA DAS for... tail-to-whole-weight conversion factor from 3.32 to 2.91, which essentially reduced the whole weight...

Selective conversion of carbon monoxide to hydrogen by anaerobic mixed culture.

PubMed

Liu, Yafeng; Wan, Jingjing; Han, Sheng; Zhang, Shicheng; Luo, Gang

2016-02-01

A new method for the conversion of CO to H2 was developed by anaerobic mixed culture in the current study. Higher CO consumption rate was obtained by anaerobic granular sludge (AGS) compared to waste activated sludge (WAS) at 55 °C and pH 7.5. However, H2 was the intermediate and CH4 was the final product. Fermentation at pH 5.5 by AGS inhibited CH4 production, while the lower CO consumption rate (50% of that at pH 7.5) and the production of acetate were found. Fermentation at pH 7.5 with the addition of chloroform achieved efficient and selective conversion of CO to H2. Stable and efficient H2 production was achieved in a continuous reactor inoculated with AGS, and gas recirculation was crucial to increase the CO conversion efficiency. Microbial community analysis showed that high abundance (44%) of unclassified sequences and low relative abundance (1%) of known CO-utilizing bacteria Desulfotomaculum were enriched in the reactor. Copyright © 2015 Elsevier Ltd. All rights reserved.

Soil Nitrogen-Cycling Responses to Conversion of Lowland Forests to Oil Palm and Rubber Plantations in Sumatra, Indonesia

PubMed Central

Tjoa, Aiyen; Veldkamp, Edzo

2015-01-01

Rapid deforestation in Sumatra, Indonesia is presently occurring due to the expansion of palm oil and rubber production, fueled by an increasing global demand. Our study aimed to assess changes in soil-N cycling rates with conversion of forest to oil palm (Elaeis guineensis) and rubber (Hevea brasiliensis) plantations. In Jambi Province, Sumatra, Indonesia, we selected two soil landscapes – loam and clay Acrisol soils – each with four land-use types: lowland forest and forest with regenerating rubber (hereafter, “jungle rubber”) as reference land uses, and rubber and oil palm as converted land uses. Gross soil-N cycling rates were measured using the 15N pool dilution technique with in-situ incubation of soil cores. In the loam Acrisol soil, where fertility was low, microbial biomass, gross N mineralization and NH4 + immobilization were also low and no significant changes were detected with land-use conversion. The clay Acrisol soil which had higher initial fertility based on the reference land uses (i.e. higher pH, organic C, total N, effective cation exchange capacity (ECEC) and base saturation) (P≤0.05–0.09) had larger microbial biomass and NH4 + transformation rates (P≤0.05) compared to the loam Acrisol soil. Conversion of forest and jungle rubber to rubber and oil palm in the clay Acrisol soil decreased soil fertility which, in turn, reduced microbial biomass and consequently decreased NH4 + transformation rates (P≤0.05–0.09). This was further attested by the correlation of gross N mineralization and microbial biomass N with ECEC, organic C, total N (R=0.51–0. 76; P≤0.05) and C:N ratio (R=-0.71 – -0.75, P≤0.05). Our findings suggest that the larger the initial soil fertility and N availability, the larger the reductions upon land-use conversion. Because soil N availability was dependent on microbial biomass, management practices in converted oil palm and rubber plantations should focus on enriching microbial biomass. PMID:26222690

Selenium Assimilation and Volatilization from Dimethylselenoniopropionate by Indian Mustard1

PubMed Central

de Souza, Mark P.; Lytle, C. Mel; Mulholland, Maria M.; Otte, Marinus L.; Terry, Norman

2000-01-01

Earlier work from our laboratory on Indian mustard (Brassica juncea L.) identified the following rate-limiting steps for the assimilation and volatilization of selenate to dimethyl selenide (DMSe): (a) uptake of selenate, (b) activation of selenate by ATP sulfurylase, and (b) conversion of selenomethionine (SeMet) to DMSe. The present study showed that shoots of selenate-treated plants accumulated very low concentrations of dimethylselenoniopropionate (DMSeP). Selenonium compounds such as DMSeP are the most likely precursors of DMSe. DMSeP-supplied plants volatilized Se at a rate 113 times higher than that measured from plants supplied with selenate, 38 times higher than from selenite, and six times higher than from SeMet. The conversion of SeMet to selenonium compounds such as DMSeP is likely to be rate-limiting for DMSe production, but not the formation of DMSe from DMSeP because DMSeP was the rate of Se volatilization from faster than from SeMet and SeMet (but no DMSeP) accumulated in selenite- or SeMet-supplied wild-type plants and in selenate-supplied ATP-sulfurylase transgenic plants. DMSeP-supplied plants absorbed the most Se from the external medium compared with plants supplied with SeMet, selenate, or selenite; they also accumulated more Se in shoots than in roots as an unknown organic compound resembling a mixture of DMSeP and selenocysteine. PMID:10759525

Day versus night laparoscopic cholecystectomy for acute cholecystitis: A comparison of outcomes and cost.

PubMed

Siada, Sammy S; Schaetzel, Shaina S; Chen, Allen K; Hoang, Huy D; Wilder, Fatima G; Dirks, Rachel C; Kaups, Krista L; Davis, James W

2017-12-01

Recent studies have suggested higher complication and conversion to open rates for nighttime laparoscopic cholecystectomy (LC) and recommend against the practice. We hypothesize that patients undergoing night LC for acute cholecystitis have decreased hospital length of stay and cost with no difference in complication and conversion rates. A retrospective review of patients with acute cholecystitis who underwent LC from October 2011 through June 2015 was performed. Complication rates, length of stay, and cost of hospitalization were compared between patients undergoing day cholecystectomy and night cholecystectomy. Complication rates and costs did not differ between the day and night groups. Length of stay was shorter in the night group (2.4 vs 2.8 days, p = 0.002). Performing LC for acute cholecystitis during night-time hours does not increase risk of complications and decreases length of stay. Copyright © 2017 Elsevier Inc. All rights reserved.

Variation in the molecular clock of primates.

PubMed

Moorjani, Priya; Amorim, Carlos Eduardo G; Arndt, Peter F; Przeworski, Molly

2016-09-20

Events in primate evolution are often dated by assuming a constant rate of substitution per unit time, but the validity of this assumption remains unclear. Among mammals, it is well known that there exists substantial variation in yearly substitution rates. Such variation is to be expected from differences in life history traits, suggesting it should also be found among primates. Motivated by these considerations, we analyze whole genomes from 10 primate species, including Old World Monkeys (OWMs), New World Monkeys (NWMs), and apes, focusing on putatively neutral autosomal sites and controlling for possible effects of biased gene conversion and methylation at CpG sites. We find that substitution rates are up to 64% higher in lineages leading from the hominoid-NWM ancestor to NWMs than to apes. Within apes, rates are ∼2% higher in chimpanzees and ∼7% higher in the gorilla than in humans. Substitution types subject to biased gene conversion show no more variation among species than those not subject to it. Not all mutation types behave similarly, however; in particular, transitions at CpG sites exhibit a more clocklike behavior than do other types, presumably because of their nonreplicative origin. Thus, not only the total rate, but also the mutational spectrum, varies among primates. This finding suggests that events in primate evolution are most reliably dated using CpG transitions. Taking this approach, we estimate the human and chimpanzee divergence time is 12.1 million years,​ and the human and gorilla divergence time is 15.1 million years​.

Specificity and kinetics of haloalkane dehalogenase.

PubMed

Schanstra, J P; Kingma, J; Janssen, D B

1996-06-21

Haloalkane dehalogenase converts halogenated alkanes to their corresponding alcohols. The active site is buried inside the protein and lined with hydrophobic residues. The reaction proceeds via a covalent substrate-enzyme complex. This paper describes a steady-state and pre-steady-state kinetic analysis of the conversion of a number of substrates of the dehalogenase. The kinetic mechanism for the "natural" substrate 1,2-dichloroethane and for the brominated analog and nematocide 1,2-dibromoethane are given. In general, brominated substrates had a lower Km, but a similar kcat than the chlorinated analogs. The rate of C-Br bond cleavage was higher than the rate of C-Cl bond cleavage, which is in agreement with the leaving group abilities of these halogens. The lower Km for brominated compounds therefore originates both from the higher rate of C-Br bond cleavage and from a lower Ks for bromo-compounds. However, the rate-determining step in the conversion (kcat) of 1, 2-dibromoethane and 1,2-dichloroethane was found to be release of the charged halide ion out of the active site cavity, explaining the different Km but similar kcat values for these compounds. The study provides a basis for the analysis of rate-determining steps in the hydrolysis of various environmentally important substrates.

Communication—Electrolysis at High Efficiency with Remarkable Hydrogen Production Rates

DOE PAGES

Wood, Anthony; He, Hongpeng; Joia, Tahir; ...

2016-01-20

Solid Oxide Electrolysis (SOE) can be used to produce hydrogen with very high efficiencies at remarkable hydrogen production rates. Through microstructural and compositional modification, conventional low cost Solid Oxide Fuel Cell (SOFC) materials have been used to create a Solid Oxide Electrolysis Cell (SOEC) that can achieve remarkable current density at cell voltages allowing higher conversion efficiency than current commercial electrolysers. Current densities in excess of 6 A/cm2 have been achieved at 800°C with a cell voltage of < 1.67 V. This cell shows a more than 3-fold increase in hydrogen production rate at higher efficiency than established commercial electrolysers.

Form and Function of Clostridium thermocellum Biofilms

PubMed Central

Dumitrache, Alexandru; Allen, Grant; Liss, Steven N.; Lynd, Lee R.

2013-01-01

The importance of bacterial adherence has been acknowledged in microbial lignocellulose conversion studies; however, few reports have described the function and structure of biofilms supported by cellulosic substrates. We investigated the organization, dynamic formation, and carbon flow associated with biofilms of the obligately anaerobic cellulolytic bacterium Clostridium thermocellum 27405. Using noninvasive, in situ fluorescence imaging, we showed biofilms capable of near complete substrate conversion with a characteristic monolayered cell structure without an extracellular polymeric matrix typically seen in biofilms. Cell division at the interface and terminal endospores appeared throughout all stages of biofilm growth. Using continuous-flow reactors with a rate of dilution (2 h−1) 12-fold higher than the bacterium's maximum growth rate, we compared biofilm activity under low (44 g/liter) and high (202 g/liter) initial cellulose loading. The average hydrolysis rate was over 3-fold higher in the latter case, while the proportions of oligomeric cellulose hydrolysis products lost from the biofilm were 13.7% and 29.1% of the total substrate carbon hydrolyzed, respectively. Fermentative catabolism was comparable between the two cellulose loadings, with ca. 4% of metabolized sugar carbon being utilized for cell production, while 75.4% and 66.7% of the two cellulose loadings, respectively, were converted to primary carbon metabolites (ethanol, acetic acid, lactic acid, carbon dioxide). However, there was a notable difference in the ethanol-to-acetic acid ratio (g/g), measured to be 0.91 for the low cellulose loading and 0.41 for the high cellulose loading. The results suggest that substrate availability for cell attachment rather than biofilm colonization rates govern the efficiency of cellulose conversion. PMID:23087042

Form and function of Clostridium thermocellum biofilms.

PubMed

Dumitrache, Alexandru; Wolfaardt, Gideon; Allen, Grant; Liss, Steven N; Lynd, Lee R

2013-01-01

The importance of bacterial adherence has been acknowledged in microbial lignocellulose conversion studies; however, few reports have described the function and structure of biofilms supported by cellulosic substrates. We investigated the organization, dynamic formation, and carbon flow associated with biofilms of the obligately anaerobic cellulolytic bacterium Clostridium thermocellum 27405. Using noninvasive, in situ fluorescence imaging, we showed biofilms capable of near complete substrate conversion with a characteristic monolayered cell structure without an extracellular polymeric matrix typically seen in biofilms. Cell division at the interface and terminal endospores appeared throughout all stages of biofilm growth. Using continuous-flow reactors with a rate of dilution (2 h(-1)) 12-fold higher than the bacterium's maximum growth rate, we compared biofilm activity under low (44 g/liter) and high (202 g/liter) initial cellulose loading. The average hydrolysis rate was over 3-fold higher in the latter case, while the proportions of oligomeric cellulose hydrolysis products lost from the biofilm were 13.7% and 29.1% of the total substrate carbon hydrolyzed, respectively. Fermentative catabolism was comparable between the two cellulose loadings, with ca. 4% of metabolized sugar carbon being utilized for cell production, while 75.4% and 66.7% of the two cellulose loadings, respectively, were converted to primary carbon metabolites (ethanol, acetic acid, lactic acid, carbon dioxide). However, there was a notable difference in the ethanol-to-acetic acid ratio (g/g), measured to be 0.91 for the low cellulose loading and 0.41 for the high cellulose loading. The results suggest that substrate availability for cell attachment rather than biofilm colonization rates govern the efficiency of cellulose conversion.

Assessing the potential additionality of certification by the Round table on Responsible Soybeans and the Roundtable on Sustainable Palm Oil

NASA Astrophysics Data System (ADS)

Garrett, Rachael D.; Carlson, Kimberly M.; Rueda, Ximena; Noojipady, Praveen

2016-04-01

Multi-stakeholder roundtables offering certification programs are promising voluntary governance mechanisms to address sustainability issues associated with international agricultural supply chains. Yet, little is known about whether roundtable certifications confer additionality, the benefits of certification beyond what would be expected from policies and practices currently in place. Here, we examine the potential additionality of the Round table on Responsible Soybeans (RTRS) and the Roundtable on Sustainable Palm Oil (RSPO) in mitigating conversion of native vegetation to cropland. We develop a metric of additionality based on business as usual land cover change dynamics and roundtable standard stringency relative to existing policies. We apply this metric to all countries with RTRS (n = 8) and RSPO (n = 12) certified production in 2013-2014, as well as countries that have no certified production but are among the top ten global producers in terms of soy (n = 2) and oil palm (n = 2). We find RSPO and RTRS both have substantially higher levels of stringency than existing national policies except in Brazil and Uruguay. In regions where these certification standards are adopted, the mean estimated rate of tree cover conversion to the target crop is similar for both standards. RTRS has higher mean relative stringency than the RSPO, yet RSPO countries have slightly higher enforcement levels. Therefore, mean potential additionality of RTRS and RSPO is similar across regions. Notably, countries with the highest levels of additionality have some adoption. However, with extremely low adoption rates (0.41% of 2014 global harvested area), RTRS likely has lower impact than RSPO (14%). Like most certification programs, neither roundtable is effectively targeting smallholder producers. To improve natural ecosystem protection, roundtables could target adoption to regions with low levels of environmental governance and high rates of forest-to-cropland conversion.

Globalization and its Impact on Bangladesh Economy

DTIC Science & Technology

2005-01-01

Steve Melton for providing both education and mentorship during my ten-month pursuit of a degree in Military Strategy. Thanks to my wife, Shoma... higher -quality intermediate goods and improved technologies that enhance the overall productivity of the economy. Conversely, the process of...lower real wages, job losses and income declines which have often resulted in higher poverty rates. As a result, there have been growing concerns

Use of near-IR to monitor the influence of external heating on dental composite photopolymerization.

PubMed

Trujillo, Marianela; Newman, Sheldon M; Stansbury, Jeffrey W

2004-10-01

This study was conducted to determine the effect of modest external heating on the photopolymerization kinetics and conversion of commercial dental composite restorative materials. A transmission-mode, real-time near-infrared spectroscopic technique was used to monitor the photopolymerization process in the composite materials at various temperatures between 23 and 70 degrees C. Several light curing units, differing in spectral output and power densities were compared at the different cure temperatures. Several significantly different commercial composites were compared for their response. Regardless of the curing light or composite material used, photopolymerization at a moderate curing temperature of 54.5 degrees C resulted in significantly higher immediate and final conversion values compared with room temperature photocuring. Contrary to the room temperature cured materials, at the elevated cure temperature the extent of post-cure was minor and different curing lights produced very uniform conversion values within a given material. The time required to reach a given level of conversion, established as full conversion with the room temperature cure, was reduced typically by 80-90% using the elevated curing conditions. Complementary kinetic studies confirmed the effect of cure temperature on increasing the polymerization rate in dental composites as significant. Increasing the temperature of composite resin within potentially biologically compatible limits can significantly influences resin polymerization. These increased rates and conversion could lead to improved properties of composite restorative materials.

Radiation-induced polymerization of glass forming systems. VI. Polymerization rate at higher conversion in binary systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kaetsu, I.; Ito, A.; Hayashi, K.

1973-08-01

The effect of temperature and composition on the inflection point in the time-conversion curve and the saturated conversion was investigated in the gamma -radio-induced radical polymerization of binary systems consisting of a glass- forming monomer and a solvent. In the polymerization of completely homogeneous systems such as glycidyl methacrylate (GMA) -triacetin and hydroxyethyl methacrylate (HEMA) --propylene glycol systems, the time-conversion curve has an inflection point at polymerization temperatures between T/sub vm/(T/sub v/ of monomer system) and T/sub vp/ (T/sub v/ of polymer system). Such conversions at the inflection point changed monotonically between 0 and 100% in this temperature range. T/submore » v/ was found to be 30 to 50 deg C higher than T/sub g/ (glass transition temperature) and a monotonic function of composition (monomer -- polymer -- solvent). The acceleration effect continued to 100% conversion above T/sub vp/, and no acceleration effect was observed below T/sub vm/. The saturated conversion in homogeneous systems changed monotonically between 0 and 100% for polymerization temperatures between T/sub gm/ (T/sub g/ of monomer system) and T/sub gp/(T of polymer system). T/sub g/ was also a monotonic function of composition. No saturation in conversion was observed above T/sub gp/ , and no polymerization occurred below T/sub gm/. In the polymerization of completely heterogeneous systems such as HEMA-dioctyl phthalate, no acceleration effect was observed at any temperature and composition. The saturated conversion was 100% sbove T/sub g/ of pure HEMA, and no polymerization occurred below this temperature in this system. (auth)« less

Efficient co-conversion process of chicken manure into protein feed and organic fertilizer by Hermetia illucens L. (Diptera: Stratiomyidae) larvae and functional bacteria.

PubMed

Xiao, Xiaopeng; Mazza, Lorenzo; Yu, Yongqiang; Cai, Minmin; Zheng, Longyu; Tomberlin, Jeffery K; Yu, Jeffrey; van Huis, Arnold; Yu, Ziniu; Fasulo, Salvatore; Zhang, Jibin

2018-07-01

A chicken manure management process was carried out through co-conversion of Hermetia illucens L. larvae (BSFL) with functional bacteria for producing larvae as feed stuff and organic fertilizer. Thirteen days co-conversion of 1000 kg of chicken manure inoculated with one million 6-day-old BSFL and 10 9  CFU Bacillus subtilis BSF-CL produced aging larvae, followed by eleven days of aerobic fermentation inoculated with the decomposing agent to maturity. 93.2 kg of fresh larvae were harvested from the B. subtilis BSF-CL-inoculated group, while the control group only harvested 80.4 kg of fresh larvae. Chicken manure reduction rate of the B. subtilis BSF-CL-inoculated group was 40.5%, while chicken manure reduction rate of the control group was 35.8%. The weight of BSFL increased by 15.9%, BSFL conversion rate increased by 12.7%, and chicken manure reduction rate increased by 13.4% compared to the control (no B. subtilis BSF-CL). The residue inoculated with decomposing agent had higher maturity (germination index >92%), compared with the no decomposing agent group (germination index ∼86%). The activity patterns of different enzymes further indicated that its production was more mature and stable than that of the no decomposing agent group. Physical and chemical production parameters showed that the residue inoculated with the decomposing agent was more suitable for organic fertilizer than the no decomposing agent group. Both, the co-conversion of chicken manure by BSFL with its synergistic bacteria and the aerobic fermentation with the decomposing agent required only 24 days. The results demonstrate that co-conversion process could shorten the processing time of chicken manure compared to traditional compost process. Gut bacteria could enhance manure conversion and manure reduction. We established efficient manure co-conversion process by black soldier fly and bacteria and harvest high value-added larvae mass and biofertilizer. Copyright © 2018 Elsevier Ltd. All rights reserved.

Raman studies of methane-ethane hydrate metastability.

PubMed

Ohno, Hiroshi; Strobel, Timothy A; Dec, Steven F; Sloan, E Dendy; Koh, Carolyn A

2009-03-05

The interconversion of methane-ethane hydrate from metastable to stable structures was studied using Raman spectroscopy. sI and sII hydrates were synthesized from methane-ethane gas mixtures of 65% or 93% methane in ethane and water, both with and without the kinetic hydrate inhibitor, poly(N-vinylcaprolactam). The observed faster structural conversion rate in the higher methane concentration atmosphere can be explained in terms of the differences in driving force (difference in chemical potential of water in sI and sII hydrates) and kinetics (mass transfer of gas and water rearrangement). The kinetic hydrate inhibitor increased the conversion rate at 65% methane in ethane (sI is thermodynamically stable) but retards the rate at 93% methane in ethane (sII is thermodynamically stable), implying there is a complex interaction between the polymer, water, and hydrate guests at crystal surfaces.

The "polyenviromic risk score": Aggregating environmental risk factors predicts conversion to psychosis in familial high-risk subjects.

PubMed

Padmanabhan, Jaya L; Shah, Jai L; Tandon, Neeraj; Keshavan, Matcheri S

2017-03-01

Young relatives of individuals with schizophrenia (i.e. youth at familial high-risk, FHR) are at increased risk of developing psychotic disorders, and show higher rates of psychiatric symptoms, cognitive and neurobiological abnormalities than non-relatives. It is not known whether overall exposure to environmental risk factors increases risk of conversion to psychosis in FHR subjects. Subjects consisted of a pilot longitudinal sample of 83 young FHR subjects. As a proof of principle, we examined whether an aggregate score of exposure to environmental risk factors, which we term a 'polyenviromic risk score' (PERS), could predict conversion to psychosis. The PERS combines known environmental risk factors including cannabis use, urbanicity, season of birth, paternal age, obstetric and perinatal complications, and various types of childhood adversity, each weighted by its odds ratio for association with psychosis in the literature. A higher PERS was significantly associated with conversion to psychosis in young, familial high-risk subjects (OR=1.97, p=0.009). A model combining the PERS and clinical predictors had a sensitivity of 27% and specificity of 96%. An aggregate index of environmental risk may help predict conversion to psychosis in FHR subjects. Copyright © 2016 Elsevier B.V. All rights reserved.

Method for enhancing microbial utilization rates of gases using perfluorocarbons

DOEpatents

Turick, Charles E.

1997-01-01

A method of enhancing the bacterial reduction of industrial gases using perfluorocarbons (PFCs) is disclosed. Because perfluorocarbons (PFCs) allow for a much greater solubility of gases than water does, PFCs have the potential to deliver gases in higher concentrations to microorganisms when used as an additive to microbial growth media thereby increasing the rate of the industrial gas conversion to economically viable chemicals and gases.

Effects of Lowering Dialysate Calcium Concentration on Mineral and Bone Disorders in Chronic Hemodialysis Patients: Conversion from 3.0 mEq/L to 2.75 mEq/L.

PubMed

Yamada, Shunsuke; Ueki, Kenji; Tokumoto, Masanori; Suehiro, Takaichi; Kimura, Hiroshi; Taniguchi, Masatomo; Fujimi, Satoru; Kitazono, Takanari; Tsuruya, Kazuhiko

2016-02-01

Selection of a lower dialysate calcium concentration (DCa) can reduce calcium burden and prevent vascular calcification in hemodialysis patients. However, decreased DCa can worsen mineral and bone disorders. This 1-year retrospective observational study evaluated 121 hemodialysis patients at Fukuoka Renal Clinic who underwent conversion of DCa from 3.0 mEq/L to 2.75 mEq/L. The primary outcomes were changes in serum levels of calcium, phosphate, and parathyroid hormone (PTH). The effects of baseline serum calcium and PTH levels on changes in biochemical parameters were also determined. One year after DCa conversion, mean serum calcium level decreased, while serum phosphate, alkaline phosphatase, and PTH concentrations increased. The rate of achievement of target PTH was higher in patients with lower serum PTH level at baseline, while patients with higher baseline serum PTH level tended to exceed the upper limit of the PTH target range. Patients with higher baseline serum calcium concentration showed a greater decrease in serum calcium level and a greater increase in serum PTH level at 1 year. Patients with a lower baseline serum PTH level can benefit from optimal PTH control following conversion of DCa from 3.0 mEq/L to 2.75 mEq/L. However, secondary hyperparathyroidism may be exacerbated in some patients with higher baseline serum calcium (Ca) and PTH levels. These results indicate that an individualized approach can maximize the benefits of Ca unloading after conversion to lower DCa. © 2015 International Society for Apheresis, Japanese Society for Apheresis, and Japanese Society for Dialysis Therapy.

Jennifer N. Markham | NREL

Science.gov Websites

-economic analysis Algae cultivation and separation Biomass conversion to fuels and higher values products economic modeling Discounted cash flow rate of return (DCFROR) Capital expenses Operating expense Education ;Techno-Economic Analysis for Upgrading Normal-Butanol to Jet and Hydrocarbon Fuel," presented at

Optimization of lipase-catalyzed synthesis of ginsenoside Rb1 esters using response surface methodology.

PubMed

Hu, Jiang-Ning; Lee, Jeung-Hee; Zhu, Xue-Mei; Shin, Jung-Ah; Adhikari, Prakash; Kim, Jae-Kyung; Lee, Ki-Teak

2008-11-26

In the lipase (Novozyme 435)-catalyzed synthesis of ginsenoside Rb1 esters, different acyl donors were found to affect not only the degree of conversion but also the regioselectivity. The reaction of acyl donors with short carbon chain was more effective, showing higher conversion than those with long carbon chain. Among the three solvent systems, the reaction in tert-amyl alcohol showed the highest conversion rate, while the reaction in the mixed solvent of t-BuOH and pyridine (1:1) had the lowest conversion rate. To allow the increase of GRb1 lipophilicity, we decided to further study the optimal condition of synthesis of GRb1 with vinyl decanoate with 10 carbon chain fatty acids in tert-amyl alcohol. Response surface methodology (RSM) was employed to optimize the synthesis condition. From the ridge analysis with maximum responses, the maximum GRb1 conversion was predicted to be 61.51% in a combination of factors (40.2 h, 52.95 degrees C, substrate mole ratio 275.57, and enzyme amount 39.81 mg/mL). Further, the adequacy of the predicted model was examined by additional independent experiments at the predicted maximum synthesis conditions. Results showed that the RSM was effective to optimize a combination of factors for lipase-catalyzed synthesis of ginsenoside Rb1 with vinyl decanoate.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Zhi-jie; Dai, Le-yang; Yang, De-zheng

Highlights: • A novel and high efficiency synthesizing AlN powders method combining mechanical ball milling and DBDP has been developed. • The particle size, the crystallite size, the lattice distortion, the morphology of Al{sub 2}O{sub 3} powders, and the AlN conversion rate are investigated and compared under the ball milled Al{sub 2}O{sub 3} powders with DBDP and without DBDP. • The ball milled Al{sub 2}O{sub 3} powders with DBDP have small spherical structure morphology with very fine particles size and high specific surface area, which result in a higher chemical efficiency and a higher AlN conversion rate at lower thermalmore » temperature. - Abstract: In this paper, aluminum nitride (AlN) powers have been produced with a novel and high efficiency method by thermal annealing at 1100–1600 °C of alumina (Al{sub 2}O{sub 3}) powders which were previously ball milled for various time up to 40 h with and without the assistant of dielectric barrier discharge plasma (DBDP). The ball milled Al{sub 2}O{sub 3} powders with DBDP and without DBDP and the corresponding synthesized AlN powers are characterized by X-ray diffraction, scanning electron microscope, and transmission electron microscopy. From the characteristics of the ball milled Al{sub 2}O{sub 3} powders with DBDP and without DBDP, it can be seen that the ball milled Al{sub 2}O{sub 3} powders with DBDP have small spherical structure morphology with very fine particles size and high specific surface area, which result in a higher chemical efficiency and a higher AlN conversion rate at lower thermal temperature. Meanwhile, the synthesized AlN powders can be known as hexagonal AlN with fine crystal morphology and irregular lump-like structure, and have uniform distribution with the average particle size of about between 500 nm and 1000 nm. This provides an important method for fabricating ultra fine powders and synthesizing nitrogen compounds.« less

Open conversion during minimally invasive radical prostatectomy: impact on perioperative complications and predictors from national data.

PubMed

Sharma, Vidit; Meeks, Joshua J

2014-12-01

Despite the increased use of minimally invasive radical prostatectomy, open conversion may occur due to surgical complications, surgeon inexperience or failure to progress. We used nationally representative data to quantify the impact of open conversion compared to nonconverted minimally invasive radical prostatectomy and open radical prostatectomy, and identify predictors of open conversion. Years 2004 to 2010 of the Nationwide Inpatient Sample were queried for patients who underwent radical prostatectomy to analyze the association of open conversion during minimally invasive radical prostatectomy with Clavien complications. Multivariate regression models yielded significant predictors of open conversion. From 2004 to 2010, 134,398 (95% CI 111,509-157,287) minimally invasive radical prostatectomies were performed with a 1.8% (95% CI 1.4-2.1) open conversion rate, translating to 2,360 (95% CI 2,001-2,720) conversions. Open conversion cases had a longer length of stay (4.17 vs 1.71 days, p <0.001) and higher hospital charges ($51,049 vs $37,418, p <0.001) than nonconverted cases. Of open conversion cases 45.2% experienced a complication vs 7.2% and 12.9% of minimally invasive radical prostatectomy and open radical prostatectomy cases, respectively (p <0.001). After adjusting for age and comorbidities, open conversion was associated with significantly increased odds of a Clavien grade 1, 2, 3 and 4 complication compared to nonconverted minimally invasive radical prostatectomy and open radical prostatectomy (OR range 2.913 to 15.670, p <0.001). Significant multivariate predictors of open conversion were obesity (OR 1.916), adhesions (OR 3.060), anemia (OR 5.692) and surgeon volume for minimally invasive radical prostatectomy less than 25 cases per year (OR 7.376) (all p <0.01). Open conversion during minimally invasive radical prostatectomy is associated with a higher than expected increase in complications compared to open radical prostatectomy and minimally invasive radical prostatectomy after adjusting for age and comorbidities. External validation of predictors of open conversion may prove useful in minimizing open conversion during minimally invasive radical prostatectomy. Copyright © 2014 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Laparoscopic repair of perforated peptic ulcer: single-center results.

PubMed

Guadagni, Simone; Cengeli, Ismail; Galatioto, Christian; Furbetta, Niccolò; Piero, Vincenzo Lippolis; Zocco, Giuseppe; Seccia, Massimo

2014-08-01

Perforated peptic ulcer (PPU), the most common indication for emergency gastric surgery, is associated with high morbidity and mortality rates. Outcomes might be improved by performing this procedure laparoscopically, but no consensus exists on whether the benefits of laparoscopic repair (LR) of PPU outweigh the disadvantages. From January 2002 to December 2012, 111 patients underwent surgery for perforated ulcer. A "laparoscopy-first" policy was attempted and then applied for 56 patients. The exclusion criteria for LR ruled out patients who had shock at admission, severe cardiorespiratory comorbidities, or a history of supramesocolic surgery. The aim of this study was a retrospective analysis of the 56 patients treated laparoscopically. The patient distribution was 30 men and 26 women, who had a mean age of 59 years (range 19-95 years). The mean ulcer size was 10 mm, and the Mannheim peritonitis index (MPI) was 21. LR was performed for 39 (69.6%) of the 56 patients and included peritoneal lavage, suturing of the perforation, and omental patching. Conversion to laparotomy was necessary in 17 cases (30.4%). The "conversion group" showed significant differences in ulcer size (larger ulcers: 1.9 vs. 0.7 mm; p < 0.01), ulcer-site topography (higher incidence of posterior ulcers: 5 vs. 0; p < 0.01), and MPI score (higher score: 24 vs. 20; p < 0.05). The LR group had a mean operating time of 86 min (range 50-125 min), an in-hospital morbidity rate of 7.6 %, a mortality rate of 2.5%, and a mean hospital stay of 6.7 days (range 5-12 days). None of these patients required reintervention. The results showed that LR for PPU is feasible with acceptable mortality and morbidity rates. Skill in laparoscopic abdominal emergencies is required. Perforations 1.5 cm or larger, posterior duodenal ulcers, and an MPI higher than 25 should be considered the main risk factors for conversion.

Comparison of coal reactivityduring conversion into different oxidizing medium

NASA Astrophysics Data System (ADS)

Korotkikh, A. G.; Slyusarskiy, K. V.; Larionov, K. B.; Osipov, V. I.

2016-10-01

Acoal conversion process of different coal samples into three different types of oxidizing medium (argon, air and steam) were studied by means of thermogravimetry. Two coal types with different metamorphism degree (lignite and bituminous coal) were used. The experimental procedure was carried out in non-isothermal conditions in temperature range from 373 K to 1273 K with 20 K/min heating rate. Purge gas consisted of argon and oxidizer with volumetric ratio 1:24 and had 250 ml/min flow rate.The ignition and burnout indexes were calculated to evaluate sample reactivity at different oxidizing mediums. The highest reactivity coefficient values in same atmosphere were obtained for lignite. It was caused by higher particle special surface area and volatile matter content.

Pyrolysis characteristics and kinetics of oil-based drilling cuttings in shale gas developing

NASA Astrophysics Data System (ADS)

Huang, Chuan; Li, Tong; Xu, Tengtun; Zeng, Yunmin; Song, Xue

2018-03-01

In this paper, the thermal behavior of waste oil-based drilling cuttings (from shale gas fields in Chongqing) was examined at different heating rates ranging from 5 to 15 °C min-1 in inert atmosphere using a sync analyzer of thermogravimetry (TG) and differential scanning calorimetry (DSC). Four methods were used to analyze the distributions and variations of kinetics parameter (active energy (E) and frequency gene (A)): Coats-Redfern and other three iso-conversion rate methods (Flynn-Wall-Ozawa, Vyazovkin and Friedman). The experimental results indicated that the process consists of three steps, i.e., water evaporation, volatilization of light oil component and heavy oil cracking. TG curves moved toward higher temperature zone caused by thermal hysteresis with the increase of temperature rising rate. For volatilization of lightweight components, the E calculated by three iso-conversion rate methods changed a little with conversion, and had almost the same results as the CR method (14.39˜20.08 kJ.mol-1). For reactions of heavy oil cracking with mixed mechanism, corresponding E rose gradually with the increase of reaction time. The CR method shows nonlinear trends and the reaction models and kinetic parameters cannot be extracted from CR curves. The results by three iso-conversion methods showed that apparent activation energy was given as 155.74˜561.10 kJ.mol-1, 141.06˜524.96 kJ.mol-1 and 74.37˜605.10 kJ.mol-1, respectively.

Estimating Global “Blue Carbon” Emissions from Conversion and Degradation of Vegetated Coastal Ecosystems

PubMed Central

Murray, Brian C.; Crooks, Stephen; Jenkins, W. Aaron; Sifleet, Samantha; Craft, Christopher; Fourqurean, James W.; Kauffman, J. Boone; Marbà, Núria; Megonigal, Patrick; Pidgeon, Emily; Herr, Dorothee; Gordon, David; Baldera, Alexis

2012-01-01

Recent attention has focused on the high rates of annual carbon sequestration in vegetated coastal ecosystems—marshes, mangroves, and seagrasses—that may be lost with habitat destruction (‘conversion’). Relatively unappreciated, however, is that conversion of these coastal ecosystems also impacts very large pools of previously-sequestered carbon. Residing mostly in sediments, this ‘blue carbon’ can be released to the atmosphere when these ecosystems are converted or degraded. Here we provide the first global estimates of this impact and evaluate its economic implications. Combining the best available data on global area, land-use conversion rates, and near-surface carbon stocks in each of the three ecosystems, using an uncertainty-propagation approach, we estimate that 0.15–1.02 Pg (billion tons) of carbon dioxide are being released annually, several times higher than previous estimates that account only for lost sequestration. These emissions are equivalent to 3–19% of those from deforestation globally, and result in economic damages of $US 6–42 billion annually. The largest sources of uncertainty in these estimates stems from limited certitude in global area and rates of land-use conversion, but research is also needed on the fates of ecosystem carbon upon conversion. Currently, carbon emissions from the conversion of vegetated coastal ecosystems are not included in emissions accounting or carbon market protocols, but this analysis suggests they may be disproportionally important to both. Although the relevant science supporting these initial estimates will need to be refined in coming years, it is clear that policies encouraging the sustainable management of coastal ecosystems could significantly reduce carbon emissions from the land-use sector, in addition to sustaining the well-recognized ecosystem services of coastal habitats. PMID:22962585

Catalyst and process development for synthesis gas conversion to isobutylene. Final report, September 1, 1990--January 31, 1994

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anthony, R.G.; Akgerman, A.

1994-05-06

Previous work on isosynthesis (conversion of synthesis gas to isobutane and isobutylene) was performed at very low conversions or extreme process conditions. The objectives of this research were (1) determine the optimum process conditions for isosynthesis; (2) determine the optimum catalyst preparation method and catalyst composition/properties for isosynthesis; (3) determine the kinetics for the best catalyst; (4) develop reactor models for trickle bed, slurry, and fixed bed reactors; and (5) simulate the performance of fixed bed trickle flow reactors, slurry flow reactors, and fixed bed gas phase reactors for isosynthesis. More improvement in catalyst activity and selectivity is needed beforemore » isosynthesis can become a commercially feasible (stand-alone) process. Catalysts prepared by the precipitation method show the most promise for future development as compared with those prepared hydrothermally, by calcining zirconyl nitrate, or by a modified sol-gel method. For current catalysts the high temperatures (>673 K) required for activity also cause the production of methane (because of thermodynamics). A catalyst with higher activity at lower temperatures would magnify the unique selectivity of zirconia for isobutylene. Perhaps with a more active catalyst and acidification, oxygenate production could be limited at lower temperatures. Pressures above 50 atm cause an undesirable shift in product distribution toward heavier hydrocarbons. A model was developed that can predict carbon monoxide conversion an product distribution. The rate equation for carbon monoxide conversion contains only a rate constant and an adsorption equilibrium constant. The product distribution was predicted using a simple ratio of the rate of CO conversion. This report is divided into Introduction, Experimental, and Results and Discussion sections.« less

Optimization of enzyme complexes for efficient hydrolysis of corn stover to produce glucose.

PubMed

Yu, Xiaoxiao; Liu, Yan; Meng, Jiatong; Cheng, Qiyue; Zhang, Zaixiao; Cui, Yuxiao; Liu, Jiajing; Teng, Lirong; Lu, Jiahui; Meng, Qingfan; Ren, Xiaodong

2015-05-01

Hydrolysis of cellulose to glucose is the critical step for transferring the lignocellulose to the industrial chemicals. For improving the conversion rate of cellulose of corn stover to glucose, the cocktail of celllulase with other auxiliary enzymes and chemicals was studied in this work. Single factor tests and Response Surface Methodology (RSM) were applied to optimize the enzyme mixture, targeting maximum glucose release from corn stover. The increasing rate of glucan-to-glucose conversion got the higher levels while the cellulase was added 1.7μl tween-80/g cellulose, 300μg β-glucosidase/g cellulose, 400μg pectinase/g cellulose and 0.75mg/ml sodium thiosulphate separately in single factor tests. To improve the glucan conversion, the β-glucosidase, pectinase and sodium thiosulphate were selected for next step optimization with RSM. It is showed that the maximum increasing yield was 45.8% at 377μg/g cellulose Novozyme 188, 171μg/g cellulose pectinase and 1mg/ml sodium thiosulphate.

Deception Detection: The Relationship of Levels of Trust and Perspective Taking in Real-Time Online and Offline Communication Environments.

PubMed

Friend, Catherine; Fox Hamilton, Nicola

2016-09-01

Where humans have been found to detect lies or deception only at the rate of chance in offline face-to-face communication (F2F), computer-mediated communication (CMC) online can elicit higher rates of trust and sharing of personal information than F2F. How do levels of trust and empathetic personality traits like perspective taking (PT) relate to deception detection in real-time CMC compared to F2F? A between groups correlational design (N = 40) demonstrated that, through a paired deceptive conversation task with confederates, levels of participant trust could predict accurate detection online but not offline. Second, participant PT abilities could not predict accurate detection in either conversation medium. Finally, this study found that conversation medium also had no effect on deception detection. This study finds support for the effects of the Truth Bias and online disinhibition in deception, and further implications in law enforcement are discussed.

Invasion of a semi-arid shrubland by annual grasses increases autotrophic and heterotrophic soil respiration rates due to altered soil moisture and temperature patterns

NASA Astrophysics Data System (ADS)

Mauritz, M.; Hale, I.; Lipson, D.

2010-12-01

Shrub <-> grassland conversions are a globally occurring phenomenon altering habitat structure, quality and nutrient cycling. Grasses and shrubs differ in their above and belowground biomass allocation, root architecture, phenology, litter quality and quantity. Conversion affects soil microbial communities, soil moisture and temperature and carbon (C) allocation patterns. However, the effect of conversion on C storage is regionally variable and there is no consistent direction of change. In Southern California invasion by annual grasses is a major threat to native shrub communities and it has been proposed that grass invasion increases NPP and ecosystem C storage (Wolkovich et al, 2009). In order to better understand how this shrub <-> grassland conversion changes ecosystem C storage it is important to understand the partitioning of soil respiration into autotrophic and heterotrophic components. Respiration was measured in plots under shrubs and grasses from February when it was cold and wet to July when it was hot and dry, capturing seasonal transitions in temperature and water availability. Roots were excluded under shrubs and grasses with root exclusion cores to quantify heterotrophic respiration. Using total soil respiration (Rt) = autotrophic respiration (root) (Ra)+ heterotrophic respiration (microbial) (Rh) the components contributing to total soil respiration can be evaluated. Respiration, soil moisture and temperature were measured daily at four hour intervals using Licor 8100 automated chamber measurements. Throughout the measurement period, Rt under grasses exceeded Rt under shrubs. Higher Rt levels under grasses were mainly due to higher Ra in grasses rather than changes in Rh. On average grass Ra was almost double shrub Ra. Higher grass respiration levels are partially explained by differences in soil moisture and temperature between shrubs and grasses. Respiration rates responded similarly to seasonal transitions regardless of treatment although Ra had a much stronger seasonal response. Across all months changes in respiration rates are explained by changes in soil moisture. However, within wet periods respiration rates increase with temperature. From February to April the soil was wet and respiration levels gradually increased as day time soil temperatures increased. From April onwards absence of precipitation events and rising soil temperatures caused the soils to rapidly dry out. As a result Rt rates declined and gradually converged with Rh levels. As soils dried, grass Ra declined more gradually than shrub Ra. This was contrary to our expectation that shrub roots would respire longer into the dry season because they have deeper roots and can access water. The high late-season levels of respiration observed in the grass community are possibly due to the presence of invasive forbs which have deep tap roots and continue to grow after the grasses have senesced. Conversion from native shrubs to annual invasive grasses increased both Rt and Rh which indicates changes in plant C allocation and decomposition rates of soil C. The continued encroachment of grasses on shrubland has important implications for the future of C storage in this system.

Biogasification of Walt Disney World biomass waste blend. Final report, January 1982-December 1985

DOE Office of Scientific and Technical Information (OSTI.GOV)

Biljetina, R.; Chynoweth, D.P.; Srivastava, V.J.

1986-10-01

The objective of the research is to develop efficient processes for conversion of biomass-waste blends to methane and other resources. To evaluate the technical and economic feasibility, an experimental test unit (ETU) was designed and operated at the Reedy Creek Wastewater Treatment Plant at Walt Disney World in Lake Buena Vista, Florida. The facility integrates a biomethanogenic-conversion process with a wastewater-treatment process employing water hyacinth ponds for secondary and tertiary treatment of sewage. Harvested water hyacinth is subsequently combined with sludge from the primary wastewater clarifier and fed at 1-wet-ton per day to the ETU digester. This results in themore » production of methane and other useful products. The digester was operated as a non-mixed, solids concentrating digester to encourage higher solids and microorganism retention times. Data collected during six steady-state operating periods confirmed earlier laboratory observations that this digester consistently produces 15 to 25% higher methane yields and conversions when compared to conventional stirred-tank digester. Digester operation was evaluated at different loading rates, solids blend ratios and feed configurations. Results from the program have provided a data base for the design of larger conversion systems.« less

Management of complicated gallstones: results of an alternative approach to difficult cholecystectomies.

PubMed

Lirici, Marco Maria; Califano, Andrea

2010-10-01

Laparoscopic cholecystectomy (LC) is the gold standard treatment of gallstones. Nevertheless, the incidence of conversion and injuries to the biliary tract is still high in difficult cholecystectomies. In this study we sought to determine how using operative risk predictive scores (PSs) and the Nassar scale to grade the difficulty of LC would optimize the perioperative management of complicated gallstone patients. We also evaluated whether the "fundus-first" approach to LC combined with ultrasonic dissection minimizes the risk of conversion and biliary injury in difficult cholecystectomies, and avoids routine intraoperative cholangiography. A prospective non-randomized study was carried out from 2005 to 2007 including 237 patients referred for gallbladder diseases. All patients were evaluated using an operative risk PS. The LC grade of difficulty was assessed according to Nassar. Diagnostic accuracy, sensitivity, and specificity of PS were calculated. LC in difficult cases was accomplished with a fundus-first approach. Outcome measures included: Conversion rate, bile duct (BD) injury rate, and postoperative complications according to Clavien. In 178 out of 237 patients, a higher risk of conversion and complication was predicted. In 146 out of these 178 cases, intra-operative grading confirmed the difficulty of the procedure. The PS diagnostic accuracy was 0.865, sensitivity was 100%, and specificity 65%. Positive predictive value and negative predictive value were 0.82 and 1, respectively. Conversion rate was 2.7%. Mean operating time and postoperative length of hospital stay were 75 minutes and 3.5 days. Intra-operative cholangiography was necessary in five cases, and one intraoperative biliary complication occurred with an uneventful postoperative course. Overall, postoperative complications were 2.7% with a mortality rate of 0.68% (1 myocardial infarction). Fundus-first LC by ultrasonic dissection is safe and minimizes the risk of conversion and biliary injuries in difficult cases. Difficult cholecystectomies may be predicted preoperatively; in these cases the fundus-first approach and ultrasound dissection may be advised.

Complication Rates for Hip Arthroscopy Are Underestimated: A Population-Based Study.

PubMed

Truntzer, Jeremy N; Hoppe, Daniel J; Shapiro, Lauren M; Abrams, Geoffrey D; Safran, Marc

2017-06-01

To identify major and minor complication rates associated with hip arthroscopy from a payer-based national database and compare with the rates reported in the existing literature. Patients who underwent hip arthroscopy between 2007 and 2014 were identified using PearlDiver, a publicly available database. Rates of major and minor complications, as well as conversion to total hip arthroscopy (THA), were determined by using Current Procedural Terminology (CPT) and International Classification of Diseases, Ninth Revision (ICD-9), codes. Incidence rates of select major complications across the entire database were used as a comparison group. Statistical significance was set at P < .05. Of 18 million patients screened from 2007 to 2014, a total of 2,581 hip arthroscopies were identified. The rates of major and minor complications within a 1-year postoperative period were 1.74% and 4.22%, respectively. Complications included heterotopic ossification (2.85%), bursitis (1.23%), proximal femur fracture (1.08%), deep vein thrombosis (0.79%), and hip dislocation (0.58%). The rate of conversion to THA within 1 year was 2.85%. When compared to rates in the general population, the relative risks [RRs] of requiring a THA (age <50 years, RR = 57.66, P < .001; age >50 years, RR = 22.05, P < .001), sustaining a proximal femur fracture (age <50 years, RR = 18.02, P < .001; age >50 years, RR = 2.23, P < .001), or experiencing a hip dislocation (RR 19.60, P < .001) at 1 year after hip arthroscopy were significantly higher in all age groups. Higher major complication rates after hip arthroscopy were observed using a national payer-based database than previously reported in the literature, especially in regard to hip dislocations and proximal femur fractures. Rates of total hip arthroplasty were similar to prior studies, whereas the rates of revision hip arthroscopy were higher. Level IV, case series. Copyright © 2017 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Radiation-induced polymerization of glass-forming systems. IV. Effect of the homogeneity of polymerization phase and polymer concentration on temperature dependence of initial polymerization rate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kaetsu, I.; Ito, A.; Hayashi, K.

1973-06-01

The effect of homogeneity of polymerization phase and monomer concentration on the temperature dependence of initial polymerization rate was studied in the radiation-induced radical polymerization of binary systems consisting of glass-forming monomer and solvent. In the polymerization of a completely homogeneous system such as HEMA-propylene glycol, a maximum and a minimum in polymerization rates as a function of temperature, characteristic of the polymerization in glass-forming systems, were observed for all monomer concentrations. However, in the heterogeneous polymerization systems such as HEMA-triacetin and HEMAisoamyl acetate, maximum and minimum rates were observed in monomer-rich compositions but not at low monomer concentrations. Furthermore,more » in the HEMA-dioctyl phthalate polymerization system, which is extremely heterogeneous, no maximum and minimum rates were observed at any monomer concentration. The effect of conversion on the temperature dependence of polymerization rate in homogeneous bulk polymerization of HEMA and GMA was investigated. Maximum and minimum rates were observed clearly in conversions less than 10% in the case of HEMA and less than 50% in the case of GMA, but the maximum and minimum changed to a mere inflection in the curve at higher conversions. A similar effect of polymer concentration on the temperature dependence of polymerization rate in the GMA-poly(methyl methacrylate) system was also observed. It is deduced that the change in temperature dependence of polymerization rate is attributed to the decrease in contribution of mutual termination reaction of growing chain radicals to the polymerization rate. (auth)« less

Conversion to IUI versus continuance with IVF in low responder patients: A systematic review.

PubMed

Fujii, Dennis T; Quesnell, Jodi L; Heitmann, Ryan J

2018-06-01

Poor response to ovarian hyper-stimulation can be difficult to predict prior to stimulation even when factoring in patient age and ovarian reserve testing. When faced with the situation of poor response, patients and providers have the difficult decision to proceed with oocyte retrieval, convert to intrauterine insemination (IUI), or cancel the cycle. Although this is not an uncommon scenario, there is little data available to assist with the counseling of these patients. We performed a systematic review of published studies comparing clinical pregnancy and live births between those patients continuing with in-vitro fertilization (IVF) and those converting to IUI. PubMed and Ovid were searched for all retrospective and randomized studies using the Keywords 'in-vitro fertilization', 'intrauterine insemination', 'poor responders', 'clinical pregnancy' and 'live birth rates'. A total of seven retrospective studies and one randomized control trial were reviewed. When evaluating poor responders as a group, six studies reported higher overall clinical pregnancy rates and five studies reported overall increased live birth rates with continuance of IVF. When stratified by the number of follicles produced, continuance of IVF demonstrated higher clinical pregnancy and live birth rates with ≥ 2 follicles. When only one follicle developed there were no significant differences in clinical pregnancy or live birth rates between the two groups. In patients undergoing IVF with ≤4 follicles, continuance with IVF may lead to higher clinical pregnancy and live birth compared to conversion to IUI except in patients with monofollicular development, although additional randomized controlled trials are needed to confirm these findings. Published by Elsevier B.V.

Method for enhancing microbial utilization rates of gases using perfluorocarbons

DOEpatents

Turick, C.E.

1997-06-10

A method of enhancing the bacterial reduction of industrial gases using perfluorocarbons (PFCs) is disclosed. Because perfluorocarbons (PFCs) allow for a much greater solubility of gases than water does, PFCs have the potential to deliver gases in higher concentrations to microorganisms when used as an additive to microbial growth media thereby increasing the rate of the industrial gas conversion to economically viable chemicals and gases. 3 figs.

Prospective study of cannabis use in adolescents at clinical high risk for psychosis: impact on conversion to psychosis and functional outcome.

PubMed

Auther, A M; McLaughlin, D; Carrión, R E; Nagachandran, P; Correll, C U; Cornblatt, B A

2012-12-01

Clinical and epidemiological studies suggest an association between cannabis use and psychosis but this relationship remains controversial. Clinical high-risk (CHR) subjects (age 12-22 years) with attenuated positive symptoms of psychosis (CHR+, n=101) were compared to healthy controls (HC, n=59) on rates of substance use, including cannabis. CHR+ subjects with and without lifetime cannabis use (and abuse) were compared on prodromal symptoms and social/role functioning at baseline. Participants were followed an average of 2.97 years to determine psychosis conversion status and functional outcome. At baseline, CHR+ subjects had significantly higher rates of lifetime cannabis use than HC. CHR+ lifetime cannabis users (n=35) were older (p=0.015, trend), more likely to be Caucasian (p=0.002), less socially anhedonic (p<0.001) and had higher Global Functioning: Social (GF:Social) scores (p<0.001) than non-users (n=61). CHR+ cannabis users continued to have higher social functioning than non-users at follow-up (p<0.001) but showed no differences in role functioning. A small sample of CHR+ cannabis abusers (n=10) showed similar results in that abusers were older (p=0.008), less socially anhedonic (p=0.017, trend) and had higher baseline GF:Social scores (p=0.006) than non-abusers. Logistic regression analyses revealed that conversion to psychosis in CHR+ subjects (n=15) was not related to lifetime cannabis use or abuse. The current data do not indicate that low to moderate lifetime cannabis use is a major contributor to psychosis or poor social and role functioning in clinical high-risk youth with attenuated positive symptoms of psychosis.

Conversion of municipal solid wastes to carboxylic acids by thermophilic fermentation.

PubMed

Chan, Wen Ning; Holtzapple, Mark T

2003-11-01

The purpose of this research is to generate carboxylic acids from the biodegradable fraction of municipal solid wastes (MSW) and municipal sewage sludge (MSS) by using a thermophilic (55 degrees C), anaerobic, high-solid fermentation. With terrestrial inocula, the highest total carboxylic acid concentration achieved was 20.5 g/L, the highest conversion obtained was 69%, and the highest acetic acid selectivity was 86.4%. Marine inocula were also used to compare against terrestrial sources. Continuum particle distribution modeling (CPDM) was used to predict the final acid product concentrations and substrate conversions at a wide range of liquid residence times (LRT) and volatile solid loading rates (VSLR). "Maps" showing the product concentration and conversion for various LRT and VSLR were generated from CPDM. The predictions were compared to the experimental results. On average, the difference between the predicted and experimental values were 13% for acid concentration and 10% for conversion. CPDM "maps" show that marine inocula produce higher concentrations than terrestrial inocula.

Experiment and ANSYS simulation analysis for metal aluminum solid and fluid conversion

NASA Astrophysics Data System (ADS)

Wang, Y.-Y.; Guo, P.; Wu, Y.; Zhang, Z.-L.; Jiang, S.-M.

2017-11-01

In this paper, study on metal aluminum solid and fluid conversion was carried out by using crucible resistance furnace, and observing the phenomenon of metal aluminum solid and fluid conversion. In the experiment, the same shape aluminum block was kept under the same heating rate and heated by the resistance furnace. The experimental results show that the melting point of metal aluminum is between 650°C and 660°C, and after the melting point, the metal aluminum began to melt when it maintained for a long period of time, however, when the temperature is higher than the melting point, the aluminum will melt very quickly. In addition, in ANSYS simulation, the solid aluminum melted completely at 670°C in 5430 seconds, much longer than the actual experiment, it due to the heating rate was faster, not in an ideal experimental environment and there is heat exchange with the outside world and convection, at the same time, the aluminum block may contain impurities, so the actual melting time could be shorter than the simulation. In this paper, it was explored for the liquid and solid conversion in depth, and had a certain actual value.

Time Series of Tropical-Forest Structure from TanDEM-X, Transformed to Time Series of Biomass by MODIS

NASA Astrophysics Data System (ADS)

Treuhaft, R. N.; Baccini, A.; Goncalves, F. G.; Lei, Y.; Keller, M.; Walker, W. S.

2017-12-01

Tropical forests account for about 50% of the world's forested biomass, and play a critical role in the control of atmospheric carbon dioxide. Large-scale (1000's of km) changes in forest structure and biomass bear on global carbon source-sink dynamics, while small-scale (< 100 m) changes bear on deforestation and degradation monitoring. After describing the interferometric SAR (InSAR) phase-height observation, we show forest phase-height time series from the TanDEM-X radar interferometer at X-band (3 cm), taken with monthly and sub-hectare temporal and spatial resolution, respectively. The measurements were taken with more than 30 TanDEM-X passes over Tapajós National Forest in the Brazilian Amazon between 2011 and 2014. The transformation of phase-height rates into aboveground biomass (AGB) rates is based on the idea that the change in AGB due to a change in phase-height depends on the plot's AGB. Plots with higher AGB will produce more AGB for a given increase in height or phase-height. Postulating a power-law dependence of plot-level mass density on physical height, we previously found that the best conversion factors for transforming phase-height rate to AGB rate were indeed dependent on AGB. For 78 plots, we demonstrated AGB rates from InSAR phase-height rates using AGB from field measurements. For regional modeling of the Amazon Basin, field measurements of AGB, to specify the conversion factors, is impractical. Conversion factors from InSAR phase-height rate to AGB rate in this talk will be based on AGB derived from the Moderate Resolution Imaging Spectroradiometer (MODIS). AGB measurement from MODIS is based on the spectral reflectance of 7 bands from the visible to short wave infrared, and auxiliary metrics describing the variance in reflectance. The mapping of MODIS reflectance to AGB is enabled by training a machine learning algorithm with lidar-derived AGB data, which are in turn trained by field measurements for small areas. The performance of TanDEM-X AGB rate from MODIS-derived conversion factors will be compared to that derived from field-based conversion factors. We will also attempt to improve phase-height rate to AGB rate transformation by deriving improved models of mass density dependences on height, based on the aggregation of single-stem allometrics.

Monte Carlo calculation of the neutron dose to a fetus at commercial flight altitudes

NASA Astrophysics Data System (ADS)

Alves, M. C.; Galeano, D. C.; Santos, W. S.; Hunt, John G.; d'Errico, Francesco; Souza, S. O.; de Carvalho Júnior, A. B.

2017-11-01

Aircrew members are exposed to primary cosmic rays as well as to secondary radiations from the interaction of cosmic rays with the atmosphere and with the aircraft. The radiation field at flight altitudes comprises neutrons, protons, electrons, positrons, photons, muons and pions. Generally, 50% of the effective dose to airplane passengers is due to neutrons. Care must be taken especially with pregnant aircrew members and frequent fliers so that the equivalent dose to the fetus will not exceed prescribed limits during pregnancy (1 mSv according to ICRP, and 5 mSv according to NCRP). Therefore, it is necessary to evaluate the equivalent dose to a fetus in the maternal womb. Up to now, the equivalent dose rate to a fetus at commercial flight altitudes was obtained using stylized pregnant-female phantom models. The aim of this study was calculating neutron fluence to dose conversion coefficients for a fetus of six months of gestation age using a new, realistic pregnant-female mesh-phantom. The equivalent dose rate to a fetus during an intercontinental flight was also calculated by folding our conversion coefficients with published spectral neutron flux data. The calculated equivalent dose rate to the fetus was 2.35 μSv.h-1, that is 1.5 times higher than equivalent dose rates reported in the literature. The neutron fluence to dose conversion coefficients for the fetus calculated in this study were 2.7, 3.1 and 3.9 times higher than those from previous studies using fetus models of 3, 6 and 9 months of gestation age, respectively. The differences between our study and data from the literature highlight the importance of using more realistic anthropomorphic phantoms to estimate doses to a fetus in pregnant aircrew members.

Laparoscopic versus robotic colectomy: a national surgical quality improvement project analysis.

PubMed

Dolejs, Scott C; Waters, Joshua A; Ceppa, Eugene P; Zarzaur, Ben L

2017-06-01

Robotic colorectal surgery is being increasingly adopted. Our objective was to compare early postoperative outcomes between robotic and laparoscopic colectomy in a nationally representative sample. The American College of Surgeons National Surgical Quality Improvement Project Colectomy Targeted Dataset from 2012 to 2014 was used for this study. Adult patients undergoing elective colectomy with an anastomosis were included. Patients were stratified based on location of colorectal resection (low anterior resection (LAR), left-sided resection, or right-sided resection). Bivariate data analysis was performed, and logistic regression modeling was conducted to calculate risk-adjusted 30-day outcomes. There were a total of 25,998 laparoscopic colectomies (30 % LAR's, 45 % left-sided, and 25 % right-sided) and 1484 robotic colectomies (54 % LAR's, 28 % left-sided, and 18 % right-sided). The risk-adjusted overall morbidity, serious morbidity, and mortality were similar between laparoscopic and robotic approaches in all anastomotic groups. Patients undergoing robotic LAR had a lower conversion rate (OR 0.47, 95 % CI 1.20-1.76) and postoperative sepsis rate (OR 0.49, 95 % CI 0.29-0.85) but a higher rate of diverting ostomies (OR 1.45, 95 % CI 1.20-1.76). Robotic right-sided colectomies had significantly lower conversion rates (OR 0.58, 95 % CI 0.34-0.96). Robotic colectomy in all groups was associated with a longer operative time (by 40 min) and a decreased length of stay (by 0.5 days). In a nationally representative sample comparing laparoscopic and robotic colectomies, the overall morbidity, serious morbidity, and mortality between groups are similar while length of stay was shorter by 0.5 days in the robotic colectomy group. Robotic LAR was associated with lower conversion rates and lower septic complications. However, robotic LAR is also associated with a significantly higher rate of diverting ostomy. The reason for this relationship is unclear. Surgeon factors, patient factors, and technical factors should be considered in future studies.

Modularizing Remedial Mathematics

ERIC Educational Resources Information Center

Wong, Aaron

2013-01-01

As remedial mathematics education has become an increasingly important topic of conversation in higher education. Mathematics departments have been put under increased pressure to change their programs to increase the student success rate. A number of models have been introduced over the last decade that represent a wide range of new ideas and…

Sleep Problems and Early Developmental Delay: Implications for Early Intervention Programs

ERIC Educational Resources Information Center

Bonuck, Karen; Grant, Roy

2012-01-01

Sleep disorders negatively impact behavior, cognition, and growth--the same areas targeted by early intervention. Conversely, developmental delays and disabilities may themselves precipitate sleep disorders. Young children with developmental delays experience sleep disorders at a higher rate than do typically developing children; the most common…

Winning One Program at a Time: A Systemic Approach

ERIC Educational Resources Information Center

Schultz, Adam; Zimmerman, Kay

2016-01-01

Many Universities are missing an opportunity to focus student recruitment marketing efforts and budget at the program level, which can offer lower priced advertising opportunities with higher conversion rates than traditional University level marketing initiatives. At NC State University, we have begun to deploy a scalable, low-cost, program level…

Development of immobilized cellulase through functionalized gold nano-particles for glucose production by continuous hydrolysis of waste bamboo chopsticks.

PubMed

Cheng, Cheanyeh; Chang, Kuo-Chung

2013-12-10

Cellulase immobilized on silica through the assistance of l-cysteine functionalized gold nano-particle was applied for the continuous hydrolysis of waste bamboo chopsticks powder to produce glucose. The optimal conditions for the continuous hydrolysis were pH 8.0, 50°C. A 4-day reaction with an initial 0.3 gL⁻¹ waste bamboo chopsticks powder, a feed containing 0.2 gL⁻¹ waste bamboo chopsticks powder at a continuous feed and draw rate of 0.5 mLmin⁻¹, and an enzyme loading of 40 mgcellulase(gsilica)⁻¹, has 72.0-76.6% conversion rates of repeated hydrolyses that correspond to a total production of 630.5-671.2mg glucose and are much better than batch hydrolyses. At higher enzyme loading (117 mgcellulase(gsilica)⁻¹), higher initial concentration (0.5 gL⁻¹), and higher feed concentration (0.42 gL⁻¹) the conversion rate increases to 82.9% and a total amount of 1418 mgglucose. The immobilized cellulase can be recovered easily by filtration and used repeatedly at least 6 times over a period more than 90 days with a recovered activity approximately the same as or better than previous reactions. Thus the process is promising for scaling up. Copyright © 2013 Elsevier Inc. All rights reserved.

Effect of the Molecular Nature of Mutation on the Efficiency of Intrachromosomal Gene Conversion in Mouse Cells

PubMed Central

Letsou, Anthea; Liskay, R. Michael

1987-01-01

With the intent of further exploring the nature of gene conversion in mammalian cells, we systematically addressed the effects of the molecular nature of mutation on the efficiency of intrachromosomal gene conversion in cultured mouse cells. Comparison of conversion rates revealed that all mutations studied were suitable substrates for gene conversion; however, we observed that the rates at which different mutations converted to wild-type could differ by two orders of magnitude. Differences in conversion rates were correlated with the molecular nature of the mutations. In general, rates of conversion decreased with increasing size of the molecular lesions. In comparisons of conversion rates for single base pair insertions and deletions we detected a genotype-directed path for conversion, by which an insertion was converted to wild-type three to four times more efficiently than was a deletion which maps to the same site. The data are discussed in relation to current theories of gene conversion, and are consistent with the idea that gene conversion in mammalian cells can result from repair of heteroduplex DNA (hDNA) intermediates. PMID:2828159

A novel transition pathway of ligand-induced topological conversion from hybrid forms to parallel forms of human telomeric G-quadruplexes

PubMed Central

Wang, Zi-Fu; Li, Ming-Hao; Chen, Wei-Wen; Hsu, Shang-Te Danny; Chang, Ta-Chau

2016-01-01

The folding topology of DNA G-quadruplexes (G4s) depends not only on their nucleotide sequences but also on environmental factors and/or ligand binding. Here, a G4 ligand, 3,6-bis(1-methyl-4-vinylpyridium iodide)-9-(1-(1-methyl-piperidinium iodide)-3,6,9-trioxaundecane) carbazole (BMVC-8C3O), can induce topological conversion of non-parallel to parallel forms in human telomeric DNA G4s. Nuclear magnetic resonance (NMR) spectroscopy with hydrogen-deuterium exchange (HDX) reveals the presence of persistent imino proton signals corresponding to the central G-quartet during topological conversion of Tel23 and Tel25 G4s from hybrid to parallel forms, implying that the transition pathway mainly involves local rearrangements. In contrast, rapid HDX was observed during the transition of 22-CTA G4 from an anti-parallel form to a parallel form, resulting in complete disappearance of all the imino proton signals, suggesting the involvement of substantial unfolding events associated with the topological transition. Site-specific imino proton NMR assignments of Tel23 G4 enable determination of the interconversion rates of individual guanine bases and detection of the presence of intermediate states. Since the rate of ligand binding is much higher than the rate of ligand-induced topological conversion, a three-state kinetic model was evoked to establish the associated energy diagram for the topological conversion of Tel23 G4 induced by BMVC-8C3O. PMID:26975658

Resting heart rate and the risk of developing impaired fasting glucose and diabetes: the Kailuan prospective study

PubMed Central

Wang, Liang; Cui, Liufu; Wang, Yanxue; Vaidya, Anand; Chen, Shuohua; Zhang, Caifeng; Zhu, Ying; Li, Dongqing; Hu, Frank B; Wu, Shouling; Gao, Xiang

2015-01-01

Background: To investigate the association between resting heart rate and the risk of developing impaired fasting glucose (IFG), diabetes and conversion from IFG to diabetes. Methods: The prospective analysis included 73 357 participants of the Kailuan cohort (57 719 men and 15 638 women). Resting heart rate was measured via electrocardiogram in 2006. Incident diabetes was defined as either the fasting blood glucose (FBG) ≥ 7.0 mmol/l or new active use of diabetes medications during the 4-year follow-up period. IFG was defined as a FBG between 5.6 and 6.9 mmol/l. A meta-analysis including seven published prospective studies focused on heart rate and diabetes risk, and our current study was then conducted using random-effects models. Results: During 4 years of follow-up, 17 463 incident IFG cases and 4 649 incident diabetes cases were identified. The corresponding adjusted hazard ratios (HRs) for each 10 beats/min increase in heart rate were 1.23 [95% confidence interval (CI): 1.19, 1.27] for incident diabetes, 1.11 (95% CI: 1.09, 1.13) for incident IFG and 1.13 (95% CI: 1.08, 1.17) for IFG to diabetes conversion. The risks of incident IFG and diabetes were significantly higher among participants aged < 50 years than those aged ≥ 50 years (P-interaction < 0.02 for both). A meta-analysis confirmed the positive association between resting heart rate and diabetes risk (pooled HR for the highest vs lowest heart rate quintile = 1.59, 95% CI:1.27, 2.00; n = 8). Conclusion: Faster resting heart rate is associated with higher risk of developing IFG and diabetes, suggesting that heart rate could be used to identify individuals with a higher future risk of diabetes. PMID:26002923

Nephrectomy for benign disease in the UK: results from the British Association of Urological Surgeons nephrectomy database.

PubMed

Zelhof, Bachar; McIntyre, Iain G; Fowler, Sarah M; Napier-Hemy, Richard D; Burke, Daniel M; Grey, Ben R

2016-01-01

To summarize the practice of UK urologists with regard to nephrectomy for benign disease, documenting the indications, procedural techniques and outcomes. All patients undergoing nephrectomy for a benign condition in 2012 were identified from the British Association of Urological Surgeons (BAUS) nephrectomy database. Recorded variables included the technique of surgery, the type of minimally invasive procedure, operating time, blood loss, transfusion rate, conversion rate, intra- and postoperative complications and mortality rate. Cases were also sub-analysed according to their pathologies to determine the differences in complication rate between stone disease, pyelonephritis, non-functioning kidney and other benign lesions. To contextualize procedural complexity, the simple nephrectomy data were compared with those obtained from the BAUS stage T1 radical nephrectomy audit. A total of 1 093 nephrectomies were performed (537 non-functioning kidneys, 142 stone disease, 129 nephrectomies secondary to pyelonephritis and 285 cases with other benign conditions). Of these, 76% were performed laparoscopically. Blood loss >500 mL was noted in 74 cases with a 4.8% blood transfusion rate. The intra- and postoperative complication rates were 5.2 and 11.9%, respectively. Of the 847 minimally invasive procedures, the conversion rate was 5.9%. Patients with stone disease have the highest intra- and postoperative complications (9.9 and 23.9%, respectively) compared with other benign pathologies. The total number of T1 radical nephrectomies performed was 1 095. In comparison with T1 radical nephrectomy, simple nephrectomy carries an increased risk of conversion to an open procedure (1.8 times), a higher rate of blood transfusion (4.8 vs 2.8%), and a higher risk of intra- and postoperative complications (5.2 vs 3.7% and 11.9 vs 10%, respectively). The present study reports the largest series of nephrectomies performed for benign disease and the resultant data now support the bespoke preoperative counselling of patients. Furthermore, it confirms the commonly held view that simple nephrectomy can be more difficult than its radical counterpart. The authors suggest that the term 'simple nephrectomy' is changed to 'benign nephrectomy'. © 2015 The Authors BJU International © 2015 BJU International Published by John Wiley & Sons Ltd.

Methanol conversion to light olefins over nanostructured CeAPSO-34 catalyst: Thermodynamic analysis of overall reactions and effect of template type on catalytic properties and performance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aghamohammadi, Sogand; Reactor and Catalysis Research Center; Haghighi, Mohammad, E-mail: haghighi@sut.ac.ir

2014-02-01

Graphical abstract: In this research nanostructured CeAPSO-34 was synthesized to explore the effect of TEAOH and morpholine on its physiochemical properties and MTO performance. Prepared catalysts were characterized with XRD, FESEM, BET, FTIR and NH3-TPD techniques. The results indicated that the nature of the template determines the physiochemical properties of CeAPSO-34 due to different rate of crystal growth. The catalyst obtained by using morpholine showed longer life time as well as sustaining light olefins selectivity at higher values. Furthermore, a comprehensive thermodynamic analysis of overall reactions network was carried out to address the major channels of methanol to olefins conversion.more » - Highlights: • Introduction of Ce into SAPO-34 framework. • Comparison of CeAPSO-34 synthesized using morpholine and TEAOH. • The nature of the template determines the physiochemical properties of CeAPSO-34. • Morpholine enhances catalyst lifetime in MTO process. • Presenting a complete reaction network for MTO process. - Abstract: TEAOH and morpholine were employed in synthesis of nanostructured CeAPSO-34 molecular sieve and used in methanol to olefins conversion. Prepared samples were characterized by XRD, FESEM, EDX, BET, FTIR and NH{sub 3}-TPD techniques. XRD patterns reflected the higher crystallinity of the catalyst synthesized with morpholine. The FESEM results indicated that the nature of the template determines the morphology of nanostructured CeAPSO-34 due to different rate of crystal growth. There was a meaningful difference in the strength of both strong and weak acid sites for CeAPSO-34 catalysts synthesized with TEAOH and morpholine templates. The catalyst synthesized with morpholine showed higher desorption temperature of both weak and strong acid sites evidenced by NH{sub 3}-TPD characterization. The catalyst obtained using morpholine template had the longer lifetime and sustained desired light olefins at higher values. A comprehensive thermodynamic analysis of overall reactions network was carried out to address the major channels of methanol to olefins conversion.« less

Influence of coffee and caffeine consumption on atrial fibrillation in hypertensive patients.

PubMed

Mattioli, A V; Farinetti, A; Miloro, C; Pedrazzi, P; Mattioli, G

2011-06-01

Coffee and caffeine are widely consumed in Western countries. Little information is available on the influence of coffee and caffeine consumption on atrial fibrillation (AF) in hypertensive patients. We sought to investigate the relationship between coffee consumption and atrial fibrillation with regard to spontaneous conversion of arrhythmia. A group of 600 patients presenting with a first known episode of AF was investigated, and we identified 247 hypertensive patients. The prevalence of nutritional parameters was assessed with a food frequency questionnaire. Coffee and caffeine intake were specifically estimated. Left ventricular hypertrophy was evaluated by electrocardiogram (ECG) and echocardiogram. Coffee consumption was higher in normotensive patients. High coffee consumers were more frequent in normotensive patients compared with hypertensive patients. On the other hand, the intake of caffeine was similar in hypertensive and normotensive patients, owing to a higher intake in hypertensive patients from sources other than coffee. Within normotensive patients, we report that non-habitual and low coffee consumers showed the highest probability of spontaneous conversion (OR 1.93 95%CI 0.88-3.23; p=0.001), whereas, within hypertensive patients, moderate but not high coffee consumers had the lowest probability of spontaneous conversion (OR 1.13 95%CI 0.67-1.99; p=0.05). Coffee and caffeine consumption influence spontaneous conversion of atrial fibrillation. Normotensive non-habitual coffee consumers are more likely to convert arrhythmia within 48h from the onset of symptoms. Hypertensive patients showed a U-shaped relationship between coffee consumption and spontaneous conversion of AF, moderate coffee consumers were less likely to show spontaneous conversion of arrhythmia. Patients with left ventricular hypertrophy showed a reduced rate of spontaneous conversion of arrhythmia. Copyright © 2009 Elsevier B.V. All rights reserved.

[Clinical research of pasinizid on retreated sputum positive pulmonary tuberculosis in senilities].

PubMed

Yu, D; Wang, J; Hu, X

2001-10-01

To observe and evaluate the effect and safety of pasinizid on treatment of the senile pulmonary tuberculosis with bacteriological positive. 115 cases of the senile pulmonary tuberculosis with bacteriological positive were divided into therapy group(group A) and control group(group B1 and B2) randomly. Chemotherapy regimen: group A were treated by 3DZL2E/5DL2E mainly composed of pasinizid; group B1 were treated by 3HPZL2/5HL2E(abbreviated HP regimen); group B2 were treated by 3DZL2E/5DL2E(abbreviated SH regimen). When the chemotherapy was over, the sputum negative conversion rates were 92%, 72%, 71% in group A, group B1 and group B2 respectively. The conversion rate in group A was significantly higher than that in group B1 and group B2 (P < 0.05); focal absorption rates were 75%, 50%, 50% respectively, while the vanishing rates of cavity were 85%, 46%, 50% respectively. The rate in group A was significantly higher than that in group B1 and B2(P < 0.05); Rates of side effects were 17%, 58%, 18% respectively. The rates in group A and group B2 were apparently lower than that in group B1(P < 0.01). Bacteriological relapse rate of 2 years were 5%, 19%, 18%, respectively. The rate in group A was lower than that in group B1 and B2 (P < 0.01). The effect of pasinizid on senile retreated sputum positive pulmonary tuberculosis was better than HP and SH regimen. Due to its lower rates of side effects, it is recommended for clinical usage.

Dynamics, OH distributions and UV emission of a gliding arc at various flow-rates investigated by optical measurements

NASA Astrophysics Data System (ADS)

Zhu, Jiajian; Sun, Zhiwei; Li, Zhongshan; Ehn, Andreas; Aldén, Marcus; Salewski, Mirko; Leipold, Frank; Kusano, Yukihiro

2014-07-01

We demonstrate a plasma discharge which is generated between two diverging electrodes and extended into a gliding arc in non-equilibrium condition by an air flow at atmospheric pressure. Effects of the air flow rates on the dynamics, ground-state OH distributions and spectral characterization of UV emission of the gliding arc were investigated by optical methods. High-speed photography was utilized to reveal flow-rate dependent dynamics such as ignitions, propagation, short-cutting events, extinctions and conversions of the discharge from glowtype to spark-type. Short-cutting events and ignitions occur more frequently at higher flow rates. The anchor points of the gliding arc are mostly steady at the top of the electrodes at lower flow rates whereas at higher flow rates they glide up along the electrodes most of the time. The afterglow of fully developed gliding arcs is observed to decay over hundreds of microseconds after being electronically short-cut by a newly ignited arc. The extinction time decreases with the increase of the flow rate. The frequency of the conversion of a discharge from glow-type to spark-type increases with the flow rate. Additionally, spatial distributions of ground-state OH were investigated using planar laser-induced fluorescence. The results show that the shape, height, intensity and thickness of ground-state OH distribution vary significantly with air flow rates. Finally, UV emission of the gliding arc is measured using optical emission spectroscopy and it is found that the emission intensity of NO γ (A-X), OH (A-X) and N2 (C-B) increase with the flow rates showing more characteristics of spark-type arcs. The observed phenomena indicate the significance of the interaction between local turbulence and the gliding arc.

Putting the Focus on Performance

ERIC Educational Resources Information Center

Schaffhauser, Dian

2011-01-01

From the excesses of Wall Street to the whole mortgage mess, the issue of accountability has become part of a heated national conversation. It is a debate to which higher education is certainly no stranger. But now, with tuition rates at private and public schools rising precipitously--and state budgets shriveling--the cries for increased…

Small Colleges Need "Gold Medal Selfies"

ERIC Educational Resources Information Center

Gross, Karen

2014-01-01

Higher education has been a favorite news topic for months. President Obama and the first lady have entered the national conversation, particularly around issues of cost and graduation rates for low-income students--addressing education in the State of the Union, at White House events, and in speeches across the nation. In the midst of these…

Biohydrogen production from arabinose and glucose using extreme thermophilic anaerobic mixed cultures

PubMed Central

2012-01-01

Background Second generation hydrogen fermentation technologies using organic agricultural and forestry wastes are emerging. The efficient microbial fermentation of hexoses and pentoses resulting from the pretreatment of lingocellulosic materials is essential for the success of these processes. Results Conversion of arabinose and glucose to hydrogen, by extreme thermophilic, anaerobic, mixed cultures was studied in continuous (70°C, pH 5.5) and batch (70°C, pH 5.5 and pH 7) assays. Two expanded granular sludge bed (EGSB) reactors, Rarab and Rgluc, were continuously fed with arabinose and glucose, respectively. No significant differences in reactor performance were observed for arabinose and glucose organic loading rates (OLR) ranging from 4.3 to 7.1 kgCOD m-3 d-1. However, for an OLR of 14.2 kgCOD m-3 d-1, hydrogen production rate and hydrogen yield were higher in Rarab than in Rgluc (average hydrogen production rate of 3.2 and 2.0 LH2 L-1 d-1 and hydrogen yield of 1.10 and 0.75 molH2 mol-1substrate for Rarab and Rgluc, respectively). Lower hydrogen production in Rgluc was associated with higher lactate production. Denaturing gradient gel electrophoresis (DGGE) results revealed no significant difference on the bacterial community composition between operational periods and between the reactors. Increased hydrogen production was observed in batch experiments when hydrogen partial pressure was kept low, both with arabinose and glucose as substrate. Sugars were completely consumed and hydrogen production stimulated (62% higher) when pH 7 was used instead of pH 5.5. Conclusions Continuous hydrogen production rate from arabinose was significantly higher than from glucose, when higher organic loading rate was used. The effect of hydrogen partial pressure on hydrogen production from glucose in batch mode was related to the extent of sugar utilization and not to the efficiency of substrate conversion to hydrogen. Furthermore, at pH 7.0, sugars uptake, hydrogen production and yield were higher than at pH 5.5, with both arabinose and glucose as substrates. PMID:22330180

Modified cisplatin/interferon α-2b/doxorubicin/5-fluorouracil (PIAF) chemotherapy in patients with no hepatitis or cirrhosis is associated with improved response rate, resectability, and survival of initially unresectable hepatocellular carcinoma.

PubMed

Kaseb, Ahmed O; Shindoh, Junichi; Patt, Yehuda Z; Roses, Robert E; Zimmitti, Giuseppe; Lozano, Richard D; Hassan, Manal M; Hassabo, Hesham M; Curley, Steven A; Aloia, Thomas A; Abbruzzese, James L; Vauthey, Jean-Nicolas

2013-09-15

The purpose of this study was to evaluate the factors associated with response rate, resectability, and survival after cisplatin/interferon α-2b/doxorubicin/5-fluorouracil (PIAF) combination therapy in patients with initially unresectable hepatocellular carcinoma. The study included 2 groups of patients treated with conventional high-dose PIAF (n = 84) between 1994 and 2003 and those without hepatitis or cirrhosis treated with modified PIAF (n = 33) between 2003 and 2012. Tolerance of chemotherapy, best radiographic response, rate of conversion to curative surgery, and overall survival were analyzed and compared between the 2 groups, and multivariate and logistic regression analyses were applied to identify predictors of response and survival. The modified PIAF group had a higher median number of PIAF cycles (4 versus 2, P = .049), higher objective response rate (36% versus 15%, P = .013), higher rate of conversion to curative surgery (33% versus 10%, P = .004), and longer median overall survival (21.3 versus 10.6 months, P = .002). Multivariate analyses confirmed that positive hepatitis B serology (hazard ratio [HR] = 1.68; 95% confidence interval [CI] = 1.08-2.59) and Eastern Cooperative Oncology Group performance status ≥ 2 (HR = 1.75; 95% CI = 1.04-2.93) were associated with worse survival whereas curative surgical resection after PIAF treatment (HR = 0.15; 95% CI = 0.07-0.35) was associated with improved survival. In patients with initially unresectable hepatocellular carcinoma, the modified PIAF regimen in patients with no hepatitis or cirrhosis is associated with improved response, resectability, and survival. © 2013 American Cancer Society.

Modified Cisplatin/Interferon α-2b/Doxorubicin/Fluorouracil (PIAF) chemotherapy in patients with no hepatitis or cirrhosis is associated with improved response rate, resectability and survival of initially unresectable hepatocellular carcinoma

PubMed Central

Kaseb, Ahmed O.; Shindoh, Junichi; Patt, Yehuda Z.; Roses, Robert E.; Zimmitti, Giuseppe; Lozano, Richard D.; Hassan, Manal M.; Hassabo, Hesham M.; Curley, Steven A.; Aloia, Thomas A.; Abbruzzese, James L.; Vauthey, Jean-Nicolas

2013-01-01

Purpose The purposes of this study was to evaluate the factors associated with response rate, resectability, and survival after cisplatin/interferon α-2b/doxorubicin/5-flurouracil (PIAF) combination therapy in patients with initially unresectable hepatocellular carcinoma (HCC). Patients and Methods The study included two groups of patients treated with conventional high-dose PIAF (n=84) between 1994 and 2003 and those without hepatitis or cirrhosis treated with modified PIAF (n=33) between 2003 and 2012. Tolerance of chemotherapy, best radiographic response, rate of conversion to curative surgery, and overall survival were analyzed and compared between the two groups, and multivariate and logistic regression analyses were applied to identify predictors of response and survival. Results The modified PIAF group had a higher median number of PIAF cycles (4 vs. 2, P = .049), higher objective response rate (36% vs. 15%, P = .013), higher rate of conversion to curative surgery (33% vs. 10%, P = .004), and longer median overall survival (21.3 vs. 10.6 months, P = .002). Multivariate analyses confirmed that positive hepatitis B serology (hazard ratio [HR], 1.68; 95% CI, 1.08 to 2.59) and Eastern Cooperative Oncology Group performance status ≥2 (HR, 1.75; 95% CI 1.04 to 2.93) were associated with worse survival while curative surgical resection after PIAF treatment (HR, 0.15; 95% CI, 0.07 to 0.35) was associated with improved survival. Conclusions In patients with initially unresectable HCC, the modified PIAF regimen in patients with no hepatitis or cirrhosis is associated with improved response, resectability, and survival. PMID:23821538

Calculation Methods and Conversions for Pesticide Application.

ERIC Educational Resources Information Center

Cole, Herbert, Jr.

This agriculture extension service publication from Pennsylvania State University consists of conversion tables and formulas for determining concentration and rate of application of pesticides. Contents include: (1) Area and volume conversions; (2) Important conversion formulae; (3) Conversions for rates of application; (4) Quantities of pesticide…

Carbon and nitrogen fixation differ between successional stages of biological soil crusts in the Colorado Plateau and Chihuahuan Desert

USGS Publications Warehouse

Housman, D.C.; Powers, H.H.; Collins, A.D.; Belnap, J.

2006-01-01

Biological soil crusts (cyanobacteria, mosses and lichens collectively) perform essential ecosystem services, including carbon (C) and nitrogen (N) fixation. Climate and land-use change are converting later successional soil crusts to early successional soil crusts with lower C and N fixation rates. To quantify the effect of such conversions on C and N dynamics in desert ecosystems we seasonally measured diurnal fixation rates in different biological soil crusts. We classified plots on the Colorado Plateau (Canyonlands) and Chihuahuan Desert (Jornada) as early (Microcoleus) or later successional (Nostoc/Scytonema or Placidium/Collema) and measured photosynthesis (Pn), nitrogenase activity (NA), and chlorophyll fluorescence (Fv/Fm) on metabolically active (moist) soil crusts. Later successional crusts typically had greater Pn, averaging 1.2-1.3-fold higher daily C fixation in Canyonlands and 2.4-2.8-fold higher in the Jornada. Later successional crusts also had greater NA, averaging 1.3-7.5-fold higher daily N fixation in Canyonlands and 1.3-25.0-fold higher in the Jornada. Mean daily Fv/Fm was also greater in later successional Canyonlands crusts during winter, and Jornada crusts during all seasons except summer. Together these findings indicate conversion of soil crusts back to early successional stages results in large reductions of C and N inputs into these ecosystems.

Nutrigenetic screening strains of the mulberry silkworm, Bombyx mori, for nutritional efficiency.

PubMed

Ramesha, Chinnaswamy; Lakshmi, Hothur; Kumari, Savarapu Sugnana; Anuradha, Chevva M; Kumar, Chitta Suresh

2012-01-01

The activity of sericulture is declining due the reduction of mulberry production area in sericulture practicing countries lead to adverse effects on silkworm rearing and cocoon production. Screening for nutrigenetic traits in silkworm, Bombyx mori L. (Lepidoptera: Bombycidae) is an essential prerequisite for better understanding and development of nutritionally efficient breeds/hybrids, which show less food consumption with higher efficiency conversion. The aim of this study was to identify nutritionally efficient polyvoltine silkworm strains using the germplasm breeds RMW(2), RMW(3), RMW(4), RMG(3), RMG(1), RMG(4), RMG(5), RMG(6) and APM(1) as the control. The 1(st) day of 5(th) stage silkworm larvae of polyvoltine strains were subjected to standard gravimetric analysis until spinning for three consecutive generations covering 3 different seasons on 19 nutrigenetic traits. Highly significant (p ≤ 0.001) differences were found among all nutrigenetic traits of polyvoltine silkworm strains in the experimental groups. The nutritionally efficient polvoltine silkworm strains were resulted by utilizing nutrition consumption index and efficiency of conversion of ingesta/cocoon traits as the index. Higher nutritional efficiency conversions were found in the polyvoltine silkworm strains on efficiency of conversion of ingesta to cocoon and shell than control. Comparatively smaller consumption index, respiration, metabolic rate with superior relative growth rate, and quantum of food ingesta and digesta requisite per gram of cocoon and shell were found; the lowest amount was in new polyvoltine strains compared to the control. Furthermore, based on the overall nutrigenetic traits utilized as index or 'biomarkers', three polyvoltine silkworm strains (RMG(4), RMW(2), and RMW(3)) were identified as having the potential for nutrition efficiency conversion. The data from the present study advances our knowledge for the development of nutritionally efficient silkworm breeds/hybrids and their effective commercial utilization in the sericulture industry.

Nutrigenetic screening strains of the mulberry silkworm, Bombyx mori, for nutritional efficiency.

PubMed

Chinnaswamy, Ramesha; Lakshmi, Hothur; Kumari, Savarapu S; Anuradha, Chebba M; Kumar, Chitta S

2012-01-01

The activity of sericulture is declining due the reduction of mulberry production area in sericulture practicing countries lead to adverse effects on silkworm rearing and cocoon production. Screening for nutrigenetic traits in silkworm, Bombyx mori L. (Lepidoptera: Bombycidae) is an essential prerequisite for better understanding and development of nutritionally efficient breeds/hybrids, which show less food consumption with higher efficiency conversion. The aim of this study was to identify nutritionally efficient polyvoltine silkworm strains using the germplasm breeds RMW(2), RMW(3), RMW(4), RMG(3), RMG(1), RMG(4), RMG(5), RMG(6) and APM(1) as the control. The 1(st) day of 5(th) stage silkworm larvae of polyvoltine strains were subjected to standard gravimetric analysis until spinning for three consecutive generations covering three different seasons on 19 nutrigenetic traits. Highly significant (p ≤ 0.001) differences were found among all nutrigenetic traits of polyvoltine silkworm strains in the experimental groups. The nutritionally efficient polvoltine silkworm strains were resulted by utilizing nutrition consumption index and efficiency of conversion of ingesta/cocoon traits as the index. Higher nutritional efficiency conversions were found in the polyvoltine silkworm strains on efficiency of conversion of ingesta to cocoon and shell than control. Comparatively smaller consumption index, respiration, metabolic rate with superior relative growth rate, and quantum of food ingesta and digesta requisite per gram of cocoon and shell were shown; the lowest amount was in new polyvoltine strains compared to the control. Furthermore, based on the overall nutrigenetic traits utilized as index or 'biomarkers', three polyvoltine silkworm strains (RMG(4), RMW(2), and RMW(3)) were identified as having the potential for nutrition efficiency conversion. The data from the present study advances our knowledge for the development of nutritionally efficient silkworm breeds/hybrids and their effective commercial utilization in the sericulture industry.

Nutrigenetic Screening Strains of the Mulberry Silkworm, Bombyx mori, for Nutritional Efficiency

PubMed Central

Chinnaswamy, Ramesha; Lakshmi, Hothur; Kumari, Savarapu S.; Anuradha, Chebba M.; Kumar, Chitta S.

2012-01-01

The activity of sericulture is declining due the reduction of mulberry production area in sericulture practicing countries lead to adverse effects on silkworm rearing and cocoon production. Screening for nutrigenetic traits in silkworm, Bombyx mori L. (Lepidoptera: Bombycidae) is an essential prerequisite for better understanding and development of nutritionally efficient breeds/hybrids, which show less food consumption with higher efficiency conversion. The aim of this study was to identify nutritionally efficient polyvoltine silkworm strains using the germplasm breeds RMW2, RMW3, RMW4, RMG3, RMG1, RMG4, RMG5, RMG6 and APM1 as the control. The 1st day of 5th stage silkworm larvae of polyvoltine strains were subjected to standard gravimetric analysis until spinning for three consecutive generations covering three different seasons on 19 nutrigenetic traits. Highly significant (p ≤ 0.001) differences were found among all nutrigenetic traits of polyvoltine silkworm strains in the experimental groups. The nutritionally efficient polvoltine silkworm strains were resulted by utilizing nutrition consumption index and efficiency of conversion of ingesta/cocoon traits as the index. Higher nutritional efficiency conversions were found in the polyvoltine silkworm strains on efficiency of conversion of ingesta to cocoon and shell than control. Comparatively smaller consumption index, respiration, metabolic rate with superior relative growth rate, and quantum of food ingesta and digesta requisite per gram of cocoon and shell were shown; the lowest amount was in new polyvoltine strains compared to the control. Furthermore, based on the overall nutrigenetic traits utilized as index or ‘biomarkers’, three polyvoltine silkworm strains (RMG4, RMW2, and RMW3) were identified as having the potential for nutrition efficiency conversion. The data from the present study advances our knowledge for the development of nutritionally efficient silkworm breeds/hybrids and their effective commercial utilization in the sericulture industry. PMID:22938037

Nutrigenetic Screening Strains of the Mulberry Silkworm, Bombyx mori, for Nutritional Efficiency

PubMed Central

Ramesha, Chinnaswamy; Lakshmi, Hothur; Kumari, Savarapu Sugnana; Anuradha, Chevva M.; Kumar, Chitta Suresh

2012-01-01

The activity of sericulture is declining due the reduction of mulberry production area in sericulture practicing countries lead to adverse effects on silkworm rearing and cocoon production. Screening for nutrigenetic traits in silkworm, Bombyx mori L. (Lepidoptera: Bombycidae) is an essential prerequisite for better understanding and development of nutritionally efficient breeds/hybrids, which show less food consumption with higher efficiency conversion. The aim of this study was to identify nutritionally efficient polyvoltine silkworm strains using the germplasm breeds RMW2, RMW3, RMW4, RMG3, RMG1, RMG4, RMG5, RMG6 and APM1 as the control. The 1st day of 5th stage silkworm larvae of polyvoltine strains were subjected to standard gravimetric analysis until spinning for three consecutive generations covering 3 different seasons on 19 nutrigenetic traits. Highly significant (p ≤ 0.001) differences were found among all nutrigenetic traits of polyvoltine silkworm strains in the experimental groups. The nutritionally efficient polvoltine silkworm strains were resulted by utilizing nutrition consumption index and efficiency of conversion of ingesta/cocoon traits as the index. Higher nutritional efficiency conversions were found in the polyvoltine silkworm strains on efficiency of conversion of ingesta to cocoon and shell than control. Comparatively smaller consumption index, respiration, metabolic rate with superior relative growth rate, and quantum of food ingesta and digesta requisite per gram of cocoon and shell were found; the lowest amount was in new polyvoltine strains compared to the control. Furthermore, based on the overall nutrigenetic traits utilized as index or ‘biomarkers’, three polyvoltine silkworm strains (RMG4, RMW2, and RMW3) were identified as having the potential for nutrition efficiency conversion. The data from the present study advances our knowledge for the development of nutritionally efficient silkworm breeds/hybrids and their effective commercial utilization in the sericulture industry. PMID:22934597

Sedation and Anesthesia in Pediatric and Congenital Cardiac Catheterization: A Prospective Multicenter Experience.

PubMed

Lin, C Huie; Desai, Sanyukta; Nicolas, Ramzi; Gauvreau, Kimberlee; Foerster, Susan; Sharma, Anshuman; Armsby, Laurie; Marshall, Audrey C; Odegard, Kirsten; DiNardo, James; Vincent, Julie; El-Said, Howaida; Spaeth, James; Goldstein, Bryan; Holzer, Ralf; Kreutzer, Jackie; Balzer, David; Bergersen, Lisa

2015-10-01

Sedation/anesthesia is critical to cardiac catheterization in the pediatric/congenital heart patient. We sought to identify current sedation/anesthesia practices, the serious adverse event rate related to airway, sedation, or anesthesia, and the rate of intra-procedural conversion from procedural sedation to the use of assisted ventilation or an artificial airway. Data from 13,611 patients who underwent catheterization at eight institutions were prospectively collected from 2007 to 2010. Ninety-four (0.69 %) serious sedation/airway-related adverse events occurred; events were more likely to occur in smaller patients (<4 kg, OR 4.4, 95 % CI 2.3-8.2, p < 0.001), patients with non-cardiac comorbidities (OR 1.7, 95 % CI 1.1-26, p < 0.01), and patients with low mixed venous oxygen saturation (OR 2.3, 95 % CI 1.4-3.6, p < 0.001). Nine thousand three hundred and seventy-nine (69 %) patients were initially managed with general endotracheal anesthesia, LMA, or tracheostomy, whereas 4232 (31 %) were managed with procedural sedation without an artificial airway, of which 75 (1.77 %) patients were converted to assisted ventilation/general anesthesia. Young age (<12 months, OR 5.2, 95 % CI 2.3-11.4, p < 0.001), higher-risk procedure (category 4, OR 10.1, 95 % CI 6.5-15.6, p < 0.001), and continuous pressor/inotrope requirement (OR 11.0, 95 % CI 8.6-14.0, p < 0.001) were independently associated with conversion. Cardiac catheterization in pediatric/congenital patients was associated with a low rate of serious sedation/airway-related adverse events. Smaller patients with non-cardiac comorbidities or low mixed venous oxygen saturation may be at higher risk. Patients under 1 year of age, undergoing high-risk procedures, or requiring continuous pressor/inotrope support may be at higher risk of requiring conversion from procedural sedation to assisted ventilation/general anesthesia.

Effects of Furfural on the Respiratory Metabolism of Saccharomyces cerevisiae in Glucose-Limited Chemostats

PubMed Central

Sárvári Horváth, Ilona; Franzén, Carl Johan; Taherzadeh, Mohammad J.; Niklasson, Claes; Lidén, Gunnar

2003-01-01

Effects of furfural on the aerobic metabolism of the yeast Saccharomyces cerevisiae were studied by performing chemostat experiments, and the kinetics of furfural conversion was analyzed by performing dynamic experiments. Furfural, an important inhibitor present in lignocellulosic hydrolysates, was shown to have an inhibitory effect on yeast cells growing respiratively which was much greater than the inhibitory effect previously observed for anaerobically growing yeast cells. The residual furfural concentration in the bioreactor was close to zero at all steady states obtained, and it was found that furfural was exclusively converted to furoic acid during respiratory growth. A metabolic flux analysis showed that furfural affected fluxes involved in energy metabolism. There was a 50% increase in the specific respiratory activity at the highest steady-state furfural conversion rate. Higher furfural conversion rates, obtained during pulse additions of furfural, resulted in respirofermentative metabolism, a decrease in the biomass yield, and formation of furfuryl alcohol in addition to furoic acid. Under anaerobic conditions, reduction of furfural partially replaced glycerol formation as a way to regenerate NAD+. At concentrations above the inlet concentration of furfural, which resulted in complete replacement of glycerol formation by furfuryl alcohol production, washout occurred. Similarly, when the maximum rate of oxidative conversion of furfural to furoic acid was exceeded aerobically, washout occurred. Thus, during both aerobic growth and anaerobic growth, the ability to tolerate furfural appears to be directly coupled to the ability to convert furfural to less inhibitory compounds. PMID:12839784

A comparison of methane emissions following rice paddies conversion to crab-fish farming wetlands in southeast China.

PubMed

Hu, Zhiqiang; Wu, Shuang; Ji, Cheng; Zou, Jianwen; Zhou, Quansuo; Liu, Shuwei

2016-01-01

Rice paddies and aquaculture wetlands are typical agricultural wetlands that constitute one of the important sources of atmospheric methane (CH4). Traditional transplanted rice paddies have been experiencing conversion to pond aquaculture wetlands for pursuing higher economic benefits over the past decades in southeast China. A parallel field experiment was carried out to compare CH4 emissions from a transplanted rice paddy and its converted crab-fish farming wetland in southeast China. Over the rice-growing season, CH4 fluxes averaged 1.86 mg m(-2) h(-1) from rice paddies, and 1.14 and 0.50 mg m(-2) h(-1) for the treatments with or without aquatic vegetation present in the crab-fish farming wetlands, respectively. When averaged across the treatments, seasonal CH4 emissions from crab-fish framing wetlands were 52% lower than those from rice paddies. The CH4 fluxes were negatively related to water dissolved oxygen (DO) concentration but positively related to soil/sediment dissolved organic carbon (DOC) content in crab-fish farming wetlands. Dependence of CH4 fluxes on DO or DOC was intensified by the aquatic vegetation presence. By extrapolating the present CH4 emission rate with the current rice paddy-converted aquaculture cultivation area, the seasonal CH4 emissions from inland aquaculture wetlands during the critical farming stage (20 June to 18 October) were estimated to be 33.6 Gg ha(-1) in southeast China in 2012. Rice paddies conversion to crab-fish farming wetlands might have reduced CH4 emissions by 22-54% in mainland China. Results of this study suggest that the conversion of transplanted rice paddies to crab-fish aquaculture wetlands for higher economic benefits would also lead to a lower ecosystem CH4 release rate.

Liver conversion of docosahexaenoic and arachidonic acids from their 18-carbon precursors in rats on a DHA-free but α-LNA-containing n-3 PUFA adequate diet.

PubMed

Gao, Fei; Kim, Hyung-Wook; Igarashi, Miki; Kiesewetter, Dale; Chang, Lisa; Ma, Kaizong; Rapoport, Stanley I

2011-01-01

The long-chain polyunsaturated fatty acids (PUFAs), eicosapentaenoic acid (EPA, 20:5n-3), docosahexaenoic acid (DHA, 22:6n-3), and arachidonic acid (AA, 20:4n-6), are critical for health. These PUFAs can be synthesized in liver from their plant-derived precursors, α-linolenic acid (α-LNA, 18:3n-3) and linoleic acid (LA, 18:2n-6). Vegetarians and vegans may have suboptimal long-chain n-3 PUFA status, and the extent of the conversion of α-LNA to EPA and DHA by the liver is debatable. We quantified liver conversion of DHA and other n-3 PUFAs from α-LNA in rats fed a DHA-free but α-LNA (n-3 PUFA) adequate diet, and compared results to conversion of LA to AA. [U-(13)C]LA or [U-(13)C]α-LNA was infused intravenously for 2h at a constant rate into unanesthetized rats fed a DHA-free α-LNA adequate diet, and published equations were used to calculate kinetic parameters. The conversion coefficient k(⁎) of DHA from α-LNA was much higher than for AA from LA (97.2×10(-3) vs. 10.6×10(-3)min(-1)), suggesting that liver elongation-desaturation is more selective for n-3 PUFA biosynthesis on a per molecule basis. The net daily secretion rate of DHA, 20.3μmol/day, exceeded the reported brain DHA consumption rate by 50-fold, suggesting that the liver can maintain brain DHA metabolism with an adequate dietary supply solely of α-LNA. This infusion method could be used in vegetarians or vegans to determine minimal daily requirements of EPA and DHA in humans. Published by Elsevier B.V.

Flame tube parametric studies for control of fuel bound nitrogen using rich-lean two-stage combustion

NASA Technical Reports Server (NTRS)

Schultz, D. F.; Wolfbrandt, G.

1980-01-01

An experimental parametric study of rich-lean two-stage combustion in a flame tube is described and approaches for minimizing the conversion of fuel-bound nitrogen to nitrogen oxides in a premixed, homogeneous combustion system are evaluated. Air at 672 K and 0.48 MPa was premixed with fuel blends of propane, toluene, and pyridine at primary equivalence ratios ranging from 0.5 to 2.0 and secondary equivalence ratios of 0.5 to 0.7. Distillates of SRC-II, a coal syncrude, were also tested. The blended fuels were proportioned to vary fuel hydrogen composition from 9.0 to 18.3 weight percent and fuel nitrogen composition from zero to 1.5 weight percent. Rich-lean combustion proved effective in reducing fuel nitrogen to NO sub x conversion; conversion rates up to 10 times lower than those normally produced by single-stage combustion were achieved. The optimum primary equivalence ratio, where the least NO sub x was produced and combustion efficiency was acceptable, shifted between 1.4 and 1.7 with changes in fuel nitrogen content and fuel hydrogen content. Increasing levels of fuel nitrogen content lowered the conversion rate, but not enough to avoid higher NO sub x emissions as fuel nitrogen increased.

Pressure-enhanced ortho-para conversion in solid hydrogen up to 58 GPa.

PubMed

Eggert, J H; Karmon, E; Hemley, R J; Mao, A; Goncharov, A F

1999-10-26

We measured the ortho-para conversion rate in solid hydrogen by using Raman scattering in a diamond-anvil cell, extending previous measurements by a factor of 60 in pressure. We confirm previous experiments that suggested a decrease in the conversion rate above about 0.5 GPa. We observe a distinct minimum at 3 GPa followed by a drastic increase in the conversion rate to our maximum pressure of 58 GPa. This pressure enhancement of conversion is not predicted by previous theoretical treatments and must be due to a new conversion pathway.

Appalachian versus non-Appalachian US traffic fatalities, 2008-2010

PubMed Central

Zhu, Motao; Zhao, Songzhu; Gurka, Kelly K.; Kandati, Sahiti; Coben, Jeffrey H.

2013-01-01

Purpose Though myriad health disparities exist in Appalachia, limited research has examined traffic fatalities in the region. This study compared traffic-fatality rates in Appalachia and the non-Appalachian US. Methods Fatality Analysis Reporting System and Census data from 2008-2010 were used to calculate traffic-fatality rates. Poisson models were used to estimate unadjusted (RR) and adjusted rate ratios (aRR), controlling for age, sex, and county-specific population density levels. Results: The Appalachian traffic-fatality rate was 45% (95% CI: 1.42, 1.47) higher than the non-Appalachian rate. Though only 29% of fatalities occur in rural counties in non-Appalachia versus 48% in Appalachia, rates in rural counties were similar (RR=0.97; 95% CI: 0.95, 1.00). However, the rate for urban, Appalachian counties was 42% (95% CI: 1.38, 1.45) higher than among urban, non-Appalachian counties. Appalachian rates were higher for passenger-vehicle drivers, motorcyclists, and all-terrain-vehicle riders, regardless of rurality, as well as for passenger-vehicle passengers overall and for urban counties. Conversely, Appalachia experienced lower rates among pedestrians and bicyclists, regardless of rurality. Conclusions Disparities in traffic fatality rates exist in Appalachia. Though elevated rates are partially explained by the proportion of residents living in rural settings, overall rates in urban Appalachia were consistently higher than in urban non-Appalachia. PMID:23619016

Association of household income and education with eating behaviors in Japanese adults: a cross-sectional study.

PubMed

Nakamura, Saki; Inayama, Takayo; Hata, Kikuko; Matsushita, Munehiro; Takahashi, Masaki; Harada, Kazuhiro; Arao, Takashi

2016-01-22

Socioeconomic inequalities as social determinants of health are important issues in public health and health promotion. However, the association between socioeconomic status and eating behaviors has been investigated poorly in Japanese adults. To fill this gap, the present study examines the association of eating behaviors with household income and education. The sample comprised 3,137 Japanese adults (1,580 men and 1,557 women) aged 30 to 59 years who responded to an Internet-based cross-sectional survey in 2014. Data on the following eating behaviors were collected via self-report: "taking care of one's diet for health," "eating vegetables," "frequency of eating breakfast," "frequency of family breakfasts," "frequency of family dinners," "using the information on nutrition labels," and "conversations with family or friends during meals." Self-reported data on socioeconomic status (household income and education) and demographic variables (gender, age, district of residence, marital status, residence status, and employment status) were also collected. The associations between eating behaviors and household income or education were tested using binomial logistic regression analysis with eating behaviors as dependent variables and household income and education as independent variables. A trend P -value was calculated for three categories of household income (less than 3,000,000 JPY, 3,000,000-7,000,000 JPY, and over 7,000,000 JPY) and education (junior high/high school, 2-year college, and 4-year college/graduate school). Higher household income and education were significantly associated with higher rates of eating vegetables, using the information on nutrition labels, and conversation with family or friends during meals in Japanese men and women. Higher household incomes were significantly associated with lower rates of frequency of family breakfasts in Japanese men and lower rates of frequency of family dinners in Japanese men and women. Higher socioeconomic status as indicated by household income or education was associated with eating more vegetables and conversation with family or friends during meals in Japanese men and women. Socioeconomic status should be considered in health promotion and diet improvement.

Comparison of steam gasification reactivity of algal and lignocellulosic biomass: influence of inorganic elements.

PubMed

Hognon, Céline; Dupont, Capucine; Grateau, Maguelone; Delrue, Florian

2014-07-01

This study aims at comparing the steam gasification behaviour of two species of algal biomass (Chlamydomonas reinhardtii and Arthrospira platensis) and three species of lignocellulosic biomass (miscanthus, beech and wheat straw). Isothermal experiments were carried out in a thermobalance under chemical regime. Samples had very different contents in inorganic elements, which resulted in different reactivities, with about a factor of 5 between samples. For biomasses with ratio between potassium content and phosphorus and silicon content K/(Si+P) higher than one, the reaction rate was constant during most of the reaction and then slightly increased at high conversion. On the contrary, for biomasses with ratio K/(Si+P) lower than one, the reaction rate decreased along conversion. A simple kinetic model was proposed to predict these behaviours. Copyright © 2014 Elsevier Ltd. All rights reserved.

Protection reduces loss of natural land-cover at sites of conservation importance across Africa.

PubMed

Beresford, Alison E; Eshiamwata, George W; Donald, Paul F; Balmford, Andrew; Bertzky, Bastian; Brink, Andreas B; Fishpool, Lincoln D C; Mayaux, Philippe; Phalan, Ben; Simonetti, Dario; Buchanan, Graeme M

2013-01-01

There is an emerging consensus that protected areas are key in reducing adverse land-cover change, but their efficacy remains difficult to quantify. Many previous assessments of protected area effectiveness have compared changes between sets of protected and unprotected sites that differ systematically in other potentially confounding respects (e.g. altitude, accessibility), have considered only forest loss or changes at single sites, or have analysed changes derived from land-cover data of low spatial resolution. We assessed the effectiveness of protection in reducing land-cover change in Important Bird Areas (IBAs) across Africa using a dedicated visual interpretation of higher resolution satellite imagery. We compared rates of change in natural land-cover over a c. 20-year period from around 1990 at a large number of points across 45 protected IBAs to those from 48 unprotected IBAs. A matching algorithm was used to select sample points to control for potentially confounding differences between protected and unprotected IBAs. The rate of loss of natural land-cover at sample points within protected IBAs was just 42% of that at matched points in unprotected IBAs. Conversion was especially marked in forests, but protection reduced rates of forest loss by a similar relative amount. Rates of conversion increased from the centre to the edges of both protected and unprotected IBAs, but rates of loss in 20-km buffer zones surrounding protected IBAs and unprotected IBAs were similar, with no evidence of displacement of conversion from within protected areas to their immediate surrounds (leakage).

Metabolic Conversion of Ceramides in HeLa Cells - A Cholesteryl Phosphocholine Delivery Approach

PubMed Central

Kjellberg, Matti A.; Lönnfors, Max; Slotte, J. Peter; Mattjus, Peter

2015-01-01

Ceramides can be delivered to cultured cells without solvents in the form of complexes with cholesteryl phosphocholine. We have analysed the delivery of three different radiolabeled D-erythro-ceramides (C6-Cer, C10-Cer and C16-Cer) to HeLa cells, and followed their metabolism as well as the cell viability. We found that all three ceramides were successfully taken up by HeLa cells when complexed to CholPC in an equimolar ratio, and show that the ceramides show different rates of cellular uptake and metabolic fate. The C6-Cer had the highest incorporation rate, followed by C10-Cer and C16-Cer, respectively. The subsequent effect on cell viability strongly correlated with the rate of incorporation, where C6-Cer had the strongest apoptotic effects. Low-dose (1 μM) treatment with C6-Cer favoured conversion of the precursor to sphingomyelin, whereas higher concentrations (25–100 μM) yielded increased conversion to C6-glucosylceramide. Similar results were obtained for C10-Cer. In the lower-dose C16-Cer experiments, most of the precursor was degraded, whereas at high-dose concentrations the precursor remained un-metabolized. Using this method, we demonstrate that ceramides with different chain lengths clearly exhibit varying rates of cellular uptake. The cellular fate of the externally delivered ceramides are clearly connected to their rate of incorporation and their subsequent effects on cell viability may be in part determined by their chain length. PMID:26599810

Inhibition of colorectal cancer genomic copy number alterations and chromosomal fragile site tumor suppressor FHIT and WWOX deletions by DNA mismatch repair

PubMed Central

Gelincik, Ozkan; Blecua, Pedro; Edelmann, Winfried; Kucherlapati, Raju; Zhou, Kathy; Jasin, Maria; Gümüş, Zeynep H.; Lipkin, Steven M.

2017-01-01

Homologous recombination (HR) enables precise DNA repair after DNA double strand breaks (DSBs) using identical sequence templates, whereas homeologous recombination (HeR) uses only partially homologous sequences. Homeologous recombination introduces mutations through gene conversion and genomic deletions through single-strand annealing (SSA). DNA mismatch repair (MMR) inhibits HeR, but the roles of mammalian MMR MutL homologues (MLH1, PMS2 and MLH3) proteins in HeR suppression are poorly characterized. Here, we demonstrate that mouse embryonic fibroblasts (MEFs) carrying Mlh1, Pms2, and Mlh3 mutations have higher HeR rates, by using 7,863 uniquely mapping paired direct repeat sequences (DRs) in the mouse genome as endogenous gene conversion and SSA reporters. Additionally, when DSBs are induced by gamma-radiation, Mlh1, Pms2 and Mlh3 mutant MEFs have higher DR copy number alterations (CNAs), including DR CNA hotspots previously identified in mouse MMR-deficient colorectal cancer (dMMR CRC). Analysis of The Cancer Genome Atlas CRC data revealed that dMMR CRCs have higher genome-wide DR HeR rates than MMR proficient CRCs, and that dMMR CRCs have deletion hotspots in tumor suppressors FHIT/WWOX at chromosomal fragile sites FRA3B and FRA16D (which have elevated DSB rates) flanked by paired homologous DRs and inverted repeats (IR). Overall, these data provide novel insights into the MMR-dependent HeR inhibition mechanism and its role in tumor suppression. PMID:29069730

Speech Rate Entrainment in Children and Adults With and Without Autism Spectrum Disorder.

PubMed

Wynn, Camille J; Borrie, Stephanie A; Sellers, Tyra P

2018-05-03

Conversational entrainment, a phenomenon whereby people modify their behaviors to match their communication partner, has been evidenced as critical to successful conversation. It is plausible that deficits in entrainment contribute to the conversational breakdowns and social difficulties exhibited by people with autism spectrum disorder (ASD). This study examined speech rate entrainment in children and adult populations with and without ASD. Sixty participants including typically developing children, children with ASD, typically developed adults, and adults with ASD participated in a quasi-conversational paradigm with a pseudoconfederate. The confederate's speech rate was digitally manipulated to create slow and fast speech rate conditions. Typically developed adults entrained their speech rate in the quasi-conversational paradigm, using a faster rate during the fast speech rate conditions and a slower rate during the slow speech rate conditions. This entrainment pattern was not evident in adults with ASD or in children populations. Findings suggest that speech rate entrainment is a developmentally acquired skill and offers preliminary evidence of speech rate entrainment deficits in adults with ASD. Impairments in this area may contribute to the conversational breakdowns and social difficulties experienced by this population. Future work is needed to advance this area of inquiry.

A positive return on investment: research funding by the Thoracic Surgery Foundation for Research and Education (TSFRE).

PubMed

Jones, David R; Mack, Michael J; Patterson, G Alexander; Cohn, Lawrence H

2011-05-01

The Thoracic Surgery Foundation for Research and Education (TSFRE) was formed in 1991 with the primary goals of generating new knowledge and nurturing the development of surgeon-scientists. The purpose of this article is to determine how effective the TSFRE has been in achieving these goals. A survey instrument was sent electronically to all former and current TSFRE research award recipients. Major themes included the benefits on TSFRE award recipients with respect to career choices of thoracic surgery, progress toward research independence, and the ability to leverage TSFRE funds to more substantive National Institutes of Health (NIH) awards. Success rates for NIH funding were confirmed using NIH Research Portfolio Online Reporting Tools. The total completed survey response rate was 70% (75/107). The response rates for each group were as follows: resident 74% (28/38), faculty 85% (29/34), Braunwald 50% (9/18), and TSFRE/NIH K-award 65% (11/17). The funding rate for all grants was 14% (90/619). For resident research awardees, 81% (34/42) are cardiothoracic surgeons or are thoracic surgery residents. The conversion rate for existing TSFRE/NIH co-sponsored K-awards to R01 grants is 40% at 5 years compared with a 20% K to R conversion rate for all NIH K-award recipients. K to R conversion rates for junior faculty grant awardees without a prior K-award is 44%, which is much higher than NIH rates for all new investigator R01 awards. The return on investment for TSFRE funding for surgeon-scientists is resoundingly positive with respect to promoting careers in cardiothoracic surgery and to obtaining subsequent NIH funding for thoracic surgeon investigators. Copyright © 2011 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

Adaptation of the autotrophic acetogen Sporomusa ovata to methanol accelerates the conversion of CO2 to organic products.

PubMed

Tremblay, Pier-Luc; Höglund, Daniel; Koza, Anna; Bonde, Ida; Zhang, Tian

2015-11-04

Acetogens are efficient microbial catalysts for bioprocesses converting C1 compounds into organic products. Here, an adaptive laboratory evolution approach was implemented to adapt Sporomusa ovata for faster autotrophic metabolism and CO2 conversion to organic chemicals. S. ovata was first adapted to grow quicker autotrophically with methanol, a toxic C1 compound, as the sole substrate. Better growth on different concentrations of methanol and with H2-CO2 indicated the adapted strain had a more efficient autotrophic metabolism and a higher tolerance to solvent. The growth rate on methanol was increased 5-fold. Furthermore, acetate production rate from CO2 with an electrode serving as the electron donor was increased 6.5-fold confirming that the acceleration of the autotrophic metabolism of the adapted strain is independent of the electron donor provided. Whole-genome sequencing, transcriptomic, and biochemical studies revealed that the molecular mechanisms responsible for the novel characteristics of the adapted strain were associated with the methanol oxidation pathway and the Wood-Ljungdahl pathway of acetogens along with biosynthetic pathways, cell wall components, and protein chaperones. The results demonstrate that an efficient strategy to increase rates of CO2 conversion in bioprocesses like microbial electrosynthesis is to evolve the microbial catalyst by adaptive laboratory evolution to optimize its autotrophic metabolism.

High-speed electrodeposition of copper-tin-zinc stacks from liquid metal salts for Cu2ZnSnSe4 solar cells.

PubMed

Steichen, Marc; Malaquias, João C; Arasimowicz, Monika; Djemour, Rabie; Brooks, Neil R; Van Meervelt, Luc; Fransaer, Jan; Binnemans, Koen; Dale, Phillip J

2017-01-16

Cu 2 ZnSnSe 4 -based solar cells with 5.5% power conversion efficiency were fabricated from Cu/Sn/Zn stacks electrodeposited from liquid metal salts. These electrolytes allow metal deposition rates one order of magnitude higher than those of other deposition methods.

Effect of substrate and cation requirement on anaerobic volatile fatty acid conversion rates at elevated biogas pressure.

PubMed

Lindeboom, Ralph E F; Ferrer, Ivet; Weijma, Jan; van Lier, Jules B

2013-12-01

This work studied the anaerobic conversion of neutralized volatile fatty acids (VFA) into biogas under Autogenerative High Pressure Digestion (AHPD) conditions. The effects of the operating conditions on the biogas quality, and the substrate utilisation rates were evaluated using 3 AHPD reactors (0.6 L); feeding a concentration of acetate and VFA (1-10 g COD/L) corresponding to an expected pressure increase of 1-20 bar. The biogas composition improved with pressure up to 4.5 bar (>93% CH4), and stabilized at 10 and 20 bar. Both, acetotrophic and hydrogenotrophic methanogenic activity was observed. Substrate utilisation rates of 0.2, 0.1 and 0.1 g CODCH4/g VSS/d for acetate, propionate and butyrate were found to decrease by up to 50% with increasing final pressure. Most likely increased Na(+)-requirement to achieve CO2 sequestration at higher pressure rather than end-product inhibition was responsible. Copyright © 2013 Elsevier Ltd. All rights reserved.

Pressure-enhanced ortho-para conversion in solid hydrogen up to 58 GPa

PubMed Central

Eggert, Jon H.; Karmon, Eran; Hemley, Russell J.; Mao, Ho-kwang; Goncharov, Alexander F.

1999-01-01

We measured the ortho-para conversion rate in solid hydrogen by using Raman scattering in a diamond-anvil cell, extending previous measurements by a factor of 60 in pressure. We confirm previous experiments that suggested a decrease in the conversion rate above about 0.5 GPa. We observe a distinct minimum at 3 GPa followed by a drastic increase in the conversion rate to our maximum pressure of 58 GPa. This pressure enhancement of conversion is not predicted by previous theoretical treatments and must be due to a new conversion pathway. PMID:10535910

Structured catalyst bed and method for conversion of feed materials to chemical products and liquid fuels

DOEpatents

Wang, Yong , Liu; Wei, [Richland, WA

2012-01-24

The present invention is a structured monolith reactor and method that provides for controlled Fischer-Tropsch (FT) synthesis. The invention controls mass transport limitations leading to higher CO conversion and lower methane selectivity. Over 95 wt % of the total product liquid hydrocarbons obtained from the monolithic catalyst are in the carbon range of C.sub.5-C.sub.18. The reactor controls readsorption of olefins leading to desired products with a preselected chain length distribution and enhanced overall reaction rate. And, liquid product analysis shows readsorption of olefins is reduced, achieving a narrower FT product distribution.

Not so fast: Fast speech correlates with lower lexical and structural information.

PubMed

Cohen Priva, Uriel

2017-03-01

Speakers dynamically adjust their speech rate throughout conversations. These adjustments have been linked to cognitive and communicative limitations: for example, speakers speak words that are contextually unexpected (and thus add more information) with slower speech rates. This raises the question whether limitations of this type vary wildly across speakers or are relatively constant. The latter predicts that across speakers (or conversations), speech rate and the amount of information content are inversely correlated: on average, speakers can either provide high information content or speak quickly, but not both. Using two corpus studies replicated across two corpora, I demonstrate that indeed, fast speech correlates with the use of less informative words and syntactic structures. Thus, while there are individual differences in overall information throughput, speakers are more similar in this aspect than differences in speech rate would suggest. The results suggest that information theoretic constraints on production operate at a higher level than was observed before and affect language throughout production, not only after words and structures are chosen. Copyright © 2016 Elsevier B.V. All rights reserved.

Photonic-Assisted mm-Wave and THz Wireless Transmission towards 100 Gbit/s Data Rate

NASA Astrophysics Data System (ADS)

Freire Hermelo, Maria; Chuenchom, Rattana; Rymanov, Vitaly; Kaiser, Thomas; Sheikh, Fawad; Czylwik, Andreas; Stöhr, Andreas

2017-09-01

This paper presents photonic-assisted 60 GHz mm-wave and 325 GHz system approaches that enable the transmission of spectral-efficient and high data rate signals over fiber and over air. First, we focus on generic channel characteristics within the mm-wave 60 GHz band and at the terahertz (THz) band around 325 GHz. Next, for generating the high data rate baseband signals, we present a technical solution for constructing an extreme bandwidth arbitrary waveform generator (AWG). We then report the development of a novel coherent photonic mixer (CPX) module for direct optic-to-RF conversion of extreme wideband optical signals, with a>5 dB higher conversion gain compared to conventional photodiodes. Finally, we experimentally demonstrate record spectral efficient wireless transmission for both bands. The achieved spectral efficiencies reach 10 bit/s/Hz for the 60 GHz band and 6 bit/s/Hz for the 325 GHz band. The maximum data rate transmitted at THz frequencies in the 325 GHz band is 59 Gbit/s using a 64-QAM-OFDM modulation format and a 10 GHz wide data signal.

Great majority of recombination events in Arabidopsis are gene conversion events

PubMed Central

Yang, Sihai; Yuan, Yang; Wang, Long; Li, Jing; Wang, Wen; Liu, Haoxuan; Chen, Jian-Qun; Hurst, Laurence D.; Tian, Dacheng

2012-01-01

The evolutionary importance of meiosis may not solely be associated with allelic shuffling caused by crossing-over but also have to do with its more immediate effects such as gene conversion. Although estimates of the crossing-over rate are often well resolved, the gene conversion rate is much less clear. In Arabidopsis, for example, next-generation sequencing approaches suggest that the two rates are about the same, which contrasts with indirect measures, these suggesting an excess of gene conversion. Here, we provide analysis of this problem by sequencing 40 F2 Arabidopsis plants and their parents. Small gene conversion tracts, with biased gene conversion content, represent over 90% (probably nearer 99%) of all recombination events. The rate of alteration of protein sequence caused by gene conversion is over 600 times that caused by mutation. Finally, our analysis reveals recombination hot spots and unexpectedly high recombination rates near centromeres. This may be responsible for the previously unexplained pattern of high genetic diversity near Arabidopsis centromeres. PMID:23213238

50 CFR Table 3 to Part 679 - Product Recovery Rates for Groundfish Species and Conversion Rates for Pacific Halibut

Code of Federal Regulations, 2010 CFR

2010-10-01

... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Product Recovery Rates for Groundfish Species and Conversion Rates for Pacific Halibut 3 Table 3 to Part 679 Wildlife and Fisheries FISHERY... Rates for Groundfish Species and Conversion Rates for Pacific Halibut ER28JA02.074 ER10JY02.000 ER28JA02...

When Partial Nephrectomy is Unsuccessful: Understanding the Reasons for Conversion from Robotic Partial to Radical Nephrectomy at a Tertiary Referral Center.

PubMed

Kara, Önder; Maurice, Matthew J; Mouracade, Pascal; Malkoç, Ercan; Dagenais, Julien; Nelson, Ryan J; Chavali, Jaya Sai S; Stein, Robert J; Fergany, Amr; Kaouk, Jihad H

2017-07-01

We sought to identify the preoperative factors associated with conversion from robotic partial nephrectomy to radical nephrectomy. We report the incidence of this event. Using our institutional review board approved database, we abstracted data on 1,023 robotic partial nephrectomies performed at our center between 2010 and 2015. Standard and converted cases were compared in terms of patients and tumor characteristics, and perioperative, functional and oncologic outcomes. Logistic regression analysis was done to identify predictors of radical conversion. The overall conversion rate was 3.1% (32 of 1,023 cases). The most common reasons for conversion were tumor involvement of hilar structures (8 cases or 25%), failure to achieve negative margins on frozen section (7 or 21.8%), suspicion of advanced disease (5 or 15.6%) and failure to progress (5 or 15.6%). Patients requiring conversion were older and had a higher Charlson score (both p <0.01), including an increased prevalence of chronic kidney disease (p = 0.02). Increasing tumor size (5 vs 3.1 cm, p <0.01) and R.E.N.A.L. (radius, exophytic/endophytic properties, nearness of tumor to collecting system or sinus, anterior/posterior, location relative to polar lines and hilar location) score (9 vs 8, p <0.01) were also associated with an increased risk of conversion. Worse baseline renal function (OR 0.98, 95% CI 0.96-0.99, p = 0.04), large tumor size (OR 1.44, 95% CI 1.22-1.7, p <0.01) and increasing R.E.N.A.L. score (p = 0.02) were independent predictors of conversion. Compared to converted cases, at latest followup standard robotic partial nephrectomy cases had similar short-term oncologic outcomes but better renal functional preservation (p <0.01). At a high volume center the rate of robotic partial nephrectomy conversion to radical nephrectomy was 3.1%, including 2.2% of preoperatively anticipated nephrectomy cases. Increasing tumor size and complexity, and poor preoperative renal function are the main predictors of conversion. Copyright © 2017 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Satisfaction, Settlement and Exposition: Conversation and the University Tutorial

ERIC Educational Resources Information Center

Fulford, Amanda

2013-01-01

In this paper, I consider the tutorial conversation in Higher Education. To focus the discussion I use the scenario of a tutorial conversation between a lecturer and a student. I begin by suggesting that the increasing emphasis placed on student satisfaction in certain Higher Education Institutions tends to focus the tutorial conversation towards…

Review of Computational Stirling Analysis Methods

NASA Technical Reports Server (NTRS)

Dyson, Rodger W.; Wilson, Scott D.; Tew, Roy C.

2004-01-01

Nuclear thermal to electric power conversion carries the promise of longer duration missions and higher scientific data transmission rates back to Earth for both Mars rovers and deep space missions. A free-piston Stirling convertor is a candidate technology that is considered an efficient and reliable power conversion device for such purposes. While already very efficient, it is believed that better Stirling engines can be developed if the losses inherent its current designs could be better understood. However, they are difficult to instrument and so efforts are underway to simulate a complete Stirling engine numerically. This has only recently been attempted and a review of the methods leading up to and including such computational analysis is presented. And finally it is proposed that the quality and depth of Stirling loss understanding may be improved by utilizing the higher fidelity and efficiency of recently developed numerical methods. One such method, the Ultra HI-Fl technique is presented in detail.

A New Piezoelectric Actuator Induces Bone Formation In Vivo: A Preliminary Study

PubMed Central

Reis, Joana; Frias, Clara; Canto e Castro, Carlos; Botelho, Maria Luísa; Marques, António Torres; Simões, José António Oliveira; Capela e Silva, Fernando; Potes, José

2012-01-01

This in vivo study presents the preliminary results of the use of a novel piezoelectric actuator for orthopedic application. The innovative use of the converse piezoelectric effect to mechanically stimulate bone was achieved with polyvinylidene fluoride actuators implanted in osteotomy cuts in sheep femur and tibia. The biological response around the osteotomies was assessed through histology and histomorphometry in nondecalcified sections and histochemistry and immunohistochemistry in decalcified sections, namely, through Masson's trichrome, and labeling of osteopontin, proliferating cell nuclear antigen, and tartrate-resistant acid phosphatase. After one-month implantation, total bone area and new bone area were significantly higher around actuators when compared to static controls. Bone deposition rate was also significantly higher in the mechanically stimulated areas. In these areas, osteopontin increased expression was observed. The present in vivo study suggests that piezoelectric materials and the converse piezoelectric effect may be used to effectively stimulate bone growth. PMID:22701304

Influences of observer sex, facial masculinity, and gender role identification on first impressions of men’s faces

PubMed Central

Macapagal, Kathryn R.; Rupp, Heather A.; Heiman, Julia R.

2011-01-01

Evaluations of male faces depend on attributes of the observer and target and may influence future social and sexual decisions. However, it is unknown whether adherence to hypertraditional gender roles may shape women’s evaluations of potential sexual partners or men’s evaluations of potential competitors. Using a photo task, we tested participants’ judgments of attractiveness, trustworthiness, aggressiveness, and masculinity of male faces altered to appear more masculine or feminine. Findings revealed that higher hypermasculinity scores in male observers were correlated with higher attractiveness and trustworthiness ratings of the male faces; conversely, higher hyperfemininity scores in female observers were associated with lower ratings on those traits. Male observers also rated the faces as more aggressive than did female observers. Regarding ratings by face type, masculinized faces were rated more aggressive than feminized faces, and women’s ratings did not discriminate between altered faces better than men’s ratings. These results suggest that first impressions of men can be explained in part by socioculturally- and evolutionarily-relevant factors such as the observer’s sex and gender role adherence, as well as the target’s facial masculinity. PMID:21874151

Meiotic gene-conversion rate and tract length variation in the human genome.

PubMed

Padhukasahasram, Badri; Rannala, Bruce

2013-02-27

Meiotic recombination occurs in the form of two different mechanisms called crossing-over and gene-conversion and both processes have an important role in shaping genetic variation in populations. Although variation in crossing-over rates has been studied extensively using sperm-typing experiments, pedigree studies and population genetic approaches, our knowledge of variation in gene-conversion parameters (ie, rates and mean tract lengths) remains far from complete. To explore variability in population gene-conversion rates and its relationship to crossing-over rate variation patterns, we have developed and validated using coalescent simulations a comprehensive Bayesian full-likelihood method that can jointly infer crossing-over and gene-conversion rates as well as tract lengths from population genomic data under general variable rate models with recombination hotspots. Here, we apply this new method to SNP data from multiple human populations and attempt to characterize for the first time the fine-scale variation in gene-conversion parameters along the human genome. We find that the estimated ratio of gene-conversion to crossing-over rates varies considerably across genomic regions as well as between populations. However, there is a great degree of uncertainty associated with such estimates. We also find substantial evidence for variation in the mean conversion tract length. The estimated tract lengths did not show any negative relationship with the local heterozygosity levels in our analysis.European Journal of Human Genetics advance online publication, 27 February 2013; doi:10.1038/ejhg.2013.30.

Role of various indices derived from an oral glucose tolerance test in the prediction of conversion from prediabetes to type 2 diabetes.

PubMed

Kim, Ye An; Ku, Eu Jeong; Khang, Ah Reum; Hong, Eun Shil; Kim, Kyoung Min; Moon, Jae Hoon; Choi, Sung Hee; Park, Kyong Soo; Jang, Hak Chul; Lim, Soo

2014-11-01

The clinical implications of prediabetes for development of type 2 diabetes may differ for Asian ethnicity. We investigated various indices derived from a 2-h oral glucose tolerance test (OGTT) in people with prediabetes to predict their future risk of diabetes. We recruited 406 consecutive subjects with prediabetes from 2005 to 2006 and followed them up every 3-6 months for up to 9 years. Prediabetes was defined as isolated impaired fasting glucose (IFG), isolated impaired glucose tolerance (IGT), combined glucose intolerance (CGI), or isolated elevated HbA1c (5.7-6.4%, 39-46 mmol/mol) without IFG or IGT. The rate of diabetes conversion was compared between prediabetes categories. The association of glycemic indices with development of diabetes was also investigated. Eighty-one patients were diagnosed with diabetes during the 9-year follow-up (median 46.0 months). The rate of diabetes conversion was higher in subjects with CGI (31.9%), or isolated IGT (18.5%) than in those with isolated IFG (15.2%) or isolated elevated HbA1c (10.9%). Surrogate markers reflecting β-cell dysfunction were more closely associated with diabetes conversion than insulin resistance indices. Subjects with a 30-min postload glucose ≥ 165 mg/dL and a 30-min C-peptide < 5 ng/mL had 8.83 times greater risk (95% confidence interval 2.98-26.16) of developing diabetes than other prediabetic subjects. In Asians, at least Koreans, β-cell dysfunction seems to be the major determinant for diabetes conversion. A combination of high glucose and low C-peptide levels at 30 min after OGTT may be a good predictor for diabetes conversion in this population. Copyright © 2014. Published by Elsevier Ireland Ltd.

Kinetics and mechanisms of the conversion of silicate (45S5), borate, and borosilicate glasses to hydroxyapatite in dilute phosphate solutions.

PubMed

Huang, Wenhai; Day, Delbert E; Kittiratanapiboon, Kanisa; Rahaman, Mohamed N

2006-07-01

Bioactive glasses with controllable conversion rates to hydroxyapatite (HA) may provide a novel class of scaffold materials for bone tissue engineering. The objective of the present work was to comprehensively characterize the conversion of a silicate bioactive glass (45S5), a borate glass, and two intermediate borosilicate glass compositions to HA in a dilute phosphate solution at 37 degrees Celsius. The borate glass and the borosilicate glasses were derived from the 45S5 glass by fully or partially replacing the SiO(2) with B(2)O(3). Higher B(2)O(3) content produced a more rapid conversion of the glass to HA and a lower pH value of the phosphate solution. Whereas the borate glass was fully converted to HA in less than 4 days, the silicate (45S5) and borosilicate compositions were only partially converted even after 70 days, and contained residual SiO(2) in a Na-depleted core. The concentration of Na(+) in the phosphate solution increased with reaction time whereas the PO(4) (3-) concentration decreased, both reaching final limiting values at a rate that increased with the B(2)O(3) content of the glass. However, the Ca(2+) concentration in the solution remained low, below the detection limit of atomic absorption, throughout the reaction. Immersion of the glasses in a mixed solution of K(2)HPO(4) and K(2)CO(3) produced a carbonate-substituted HA but the presence of the K(2)CO(3) had little effect on the kinetics of conversion to HA. The kinetics and mechanisms of the conversion process of the four glasses to HA are compared and used to develop a model for the process.

The physics of symbols: bridging the epistemic cut.

PubMed

Pattee, H H

2001-01-01

Evolution requires the genotype-phenotype distinction, a primeval epistemic cut that separates energy-degenerate, rate-independent genetic symbols from the rate-dependent dynamics of construction that they control. This symbol-matter or subject-object distinction occurs at all higher levels where symbols are related to a referent by an arbitrary code. The converse of control is measurement in which a rate-dependent dynamical state is coded into quiescent symbols. Non-integrable constraints are one necessary condition for bridging the epistemic cut by measurement, control, and coding. Additional properties of heteropolymer constraints are necessary for biological evolution.

Kinetic model of 1,3-specific triacylglycerols alcoholysis catalyzed by lipases.

PubMed

Pilarek, Maciej; Szewczyk, Krzysztof W

2007-01-20

A new model of enzymatic 1,3-specific alcoholysis of triacylglycerols has been developed. The irreversibility of the acyl bounds cleavage in glycerides, a reversible monoglycerides isomerization and an irreversible enzyme deactivation have been assumed. The Ping Pong Bi Bi mechanism with competitive inhibition by alcohol has been applied to describe rates of acyl bonds cleavage. The enzymatic propanolysis and iso-propanolysis of triacetin and tricaprylin catalyzed by immobilized lipase B from Candida antarctica (Novozym 435) have been investigated to verify the model. Good agreement between experimental data and calculations has been obtained. It was shown that the rate of tricaprylin alcoholysis is higher than the triacetin alcoholysis and that the rate of iso-propanolysis reactions are higher than propanolysis. The irreversible enzyme deactivation affects the conversion of glycerides whereas the competitive alcohol inhibition may be neglected. Empirical correlations of rates for monoglycerides isomerization and enzyme deactivation have been proposed.

Single-incision laparoscopic surgery for locally advanced colorectal cancer : feasibility, short-term and oncologic outcomes.

PubMed

Famiglietti, F; Leonard, D; Bachmann, R; Remue, C; Abbes Orabi, N; van Maanen, A; van den Eynde, M; Kartheuser, A

2018-01-01

Data about single-incision laparoscopic surgery (SILS) in locally advanced colorectal cancers are scarce. This study aimed to evaluate perioperative and shortterm oncologic outcomes of SILS in pT3-T4 colorectal cancer. From 2011 to 2015 data from 249 SILS performed in our Colorectal Unit were entered into a prospective database. Data regarding patients with a pT3-T4 colorectal adenocarcinoma were compared to those with pTis-pT2. Factors influencing conversion were assessed by multivariate analysis. There were 100 consecutive patients (T3-T4 = 70, Tis-T2 = 30). Demographics were similar. Tumor size was significantly larger in the T3-T4 group [3.9cm vs 2cm; p<0.001]. In T3-T4 patients we found a significant higher number of lymph nodes harvested [20 vs 13 ; p<0.001]. Early (<30 days) severe (Clavien-Dindo classification>2) postoperative complication rate was similar between groups (8.6% vs 10% ; p = 0.999), as well as conversion rate (18.6% vs 6.7% ; p = 0.220). Finally, there were no differences in terms of hospital stay and mortality rate. On multivariate analysis, age (OR = 1.06, 95%CI: 1.012-1.113 ; p = 0.015] and stage IV (OR = 5.372, 95%CI: 1.320-21.862, p = 0.019) were independently associated with conversion. SILS for locally advanced colorectal cancer did not affect the short-term outcomes in this series and oncological clearance remained satisfactory. Age and stage IV disease are independent risk factors for conversion. © Acta Gastro-Enterologica Belgica.

Diagnostic value of brain chronic black holes on T1-weighted MR images in clinically isolated syndromes.

PubMed

Mitjana, Raquel; Tintoré, Mar; Rocca, Maria A; Auger, Cristina; Barkhof, Frederik; Filippi, Massimo; Polman, Chris; Fazekas, Franz; Huerga, Elena; Montalban, Xavier; Rovira, Alex

2014-10-01

Non-enhancing black holes (neBHs) are more common in multiple sclerosis (MS) patients with longer disease durations and progressive disease subtypes. Our aim was to analyse the added value of neBHs in patients with clinically isolated syndromes (CISs) for predicting conversion to clinically definite MS (CDMS). Patients were classified based on the presence or absence of neBHs and on the number of Barkhof-Tintoré (B-T) criteria fulfilled. Dissemination in space (DIS) was defined as the presence of at least three of the four B-T criteria. Dissemination in time (DIT)1 was defined by simultaneous presence of enhancing and non-enhancing lesions. DIT2 was defined by simultaneous presence of neBHs and T2 lesions not apparent on T1-weighted images. Focal T2-hyperintense brain lesions were identified in 87.7% of the 520 CIS patients, and 41.4% of them presented at least one neBH. Patients meeting DIS, DIT1, and DIT2 had a significantly higher rate of conversion to CDMS. After adjusting for DIS, only patients who fulfilled DIT1 preserved a significant increase in CDMS conversion. Non-enhancing black holes in CIS patients are associated with a higher risk of conversion to CDMS. However, the predictive value of this finding is lost when added to the DIS criteria. © The Author(s) 2014.

Speed discrimination predicts word but not pseudo-word reading rate in adults and children

PubMed Central

Main, Keith L.; Pestilli, Franco; Mezer, Aviv; Yeatman, Jason; Martin, Ryan; Phipps, Stephanie; Wandell, Brian

2014-01-01

Word familiarity may affect magnocellular processes of word recognition. To explore this idea, we measured reading rate, speed-discrimination, and contrast detection thresholds in adults and children with a wide range of reading abilities. We found that speed-discrimination thresholds are higher in children than in adults and are correlated with age. Speed discrimination thresholds are also correlated with reading rate, but only for words, not for pseudo-words. Conversely, we found no correlation between contrast sensitivity and reading rate and no correlation between speed discrimination thresholds WASI subtest scores. These findings support the position that reading rate is influenced by magnocellular circuitry attuned to the recognition of familiar word-forms. PMID:25278418

Effects of education on the progression of early- versus late-stage mild cognitive impairment.

PubMed

Ye, Byoung Seok; Seo, Sang Won; Cho, Hanna; Kim, Seong Yoon; Lee, Jung-Sun; Kim, Eun-Joo; Lee, Yunhwan; Back, Joung Hwan; Hong, Chang Hyung; Choi, Seong Hye; Park, Kyung Won; Ku, Bon D; Moon, So Young; Kim, Sangyun; Han, Seol-Heui; Lee, Jae-Hong; Cheong, Hae-Kwan; Na, Duk L

2013-04-01

Highly educated participants with normal cognition show lower incidence of Alzheimer's disease (AD) than poorly educated participants, whereas longitudinal studies involving AD have reported that higher education is associated with more rapid cognitive decline. We aimed to evaluate whether highly educated amnestic mild cognitive impairment (aMCI) participants show more rapid cognitive decline than those with lower levels of education. A total of 249 aMCI patients enrolled from 31 memory clinics using the standard assessment and diagnostic processes were followed with neuropsychological evaluation (duration 17.2 ± 8.8 months). According to baseline performances on memory tests, participants were divided into early-stage aMCI (-1.5 to -1.0 standard deviation (SD)) and late-stage aMCI (below -1.5 SD) groups. Risk of AD conversion and changes in neuropsychological performances according to the level of education were evaluated. Sixty-two patients converted to AD over a mean follow-up of 1.43 years. The risk of AD conversion was higher in late-stage aMCI than early-stage aMCI. Cox proportional hazard models showed that aMCI participants, and late-stage aMCI participants in particular, with higher levels of education had a higher risk of AD conversion than those with lower levels of education. Late-stage aMCI participants with higher education showed faster cognitive decline in language, memory, and Clinical Dementia Rating Sum of Boxes (CDR-SOB) scores. On the contrary, early-stage aMCI participants with higher education showed slower cognitive decline in MMSE and CDR-SOB scores. Our findings suggest that the protective effects of education against cognitive decline remain in early-stage aMCI and disappear in late-stage aMCI.

Opportunities to improve the conversion of food waste to lactate: Fine-tuning secondary factors.

PubMed

RedCorn, Raymond; Engelberth, Abigail S

2017-11-01

Extensive research has demonstrated the potential for bioconversion of food waste to lactate, with major emphasis on adjusting temperature, pH, and loading rate of the fermentation. Each of these factors has a significant effect on lactate production; however, additional secondary factors have received little attention. Here we investigate three additional factors where opportunities exist for process improvement: freezing of samples during storage, discontinuous pH control, and holdover of fermentation broth between fermentations. Freezing samples prior to fermentation was shown to reduce the production rate of lactate by 8%, indicating freeze-thaw should be avoided in experiments. Prior work indicated a trade-off in pH control strategies, where discontinuous pH control correlated with higher lactate accumulation while continuous pH control correlated with higher production rate. Here we demonstrate that continuous pH control can achieve both higher lactate accumulation and higher production rate. Finally, holding over fermentation broth was shown to be a simple method to improve production rate (by 18%) at high food waste loading rates (>140 g volatile solids L -1 ) but resulted in lower lactate accumulation (by 17%). The results inform continued process improvements within the waste treatment of food waste through fermentation to lactic acid.

Conversion of Society for Maternal Fetal Medicine Abstract Presentations to Manuscript Publications

PubMed Central

Manuck, Tracy A.; Barbour, Kelli; Janicki, Lindsay; Blackwell, Sean C.; Berghella, Vincenzo

2015-01-01

Objective To evaluate the rate of conversion of Society for Maternal Fetal Medicine (SMFM) Annual Meeting abstract presentations to full manuscript publications over time. Methods Full manuscript publications corresponding to all SMFM oral abstracts 2003–2010 inclusive, and SMFM poster abstracts in 2003, 2005, 2007, and 2009 were manually searched in PubMed. An abstract was considered to ‘match’ a full publication if the abstract and publication titles as well as main methods and results were similar and the abstract first author was a publication author. In cases of uncertainty, the abstract-publication match was reviewed by a second physician researcher. Time to publication, publication rates over time, and publication rates among US vs. non-US authors were examined. PMID numbers were also collected to determine if >1 abstract contributed to a manuscript. Data were analyzed using Wilcoxon rank-sum, ANOVA, t-test, and logistic regression. Results 3,281 abstracts presented at SMFM over the study period, including 629 orals (63 main plenary, 64 fellows plenary, 502 concurrent), were reviewed. 1,780/3,281 (54.3%) were published, generating 1,582 unique publications. Oral abstracts had a consistently higher rate of conversion to publications vs. posters (77.1% vs. 48.8%, p<0.001). The median time to publication was 19 (IQR 9–36) months, and was significantly shorter for orals vs. posters (11 vs. 21 months, p<0.001). Over the study period, rates of publication of orals remained constant, but rates of publication of posters were lower in 2007 and 2009 compared to 2003 and 2005. Publications related to SMFM abstracts were published in 194 different journals, most commonly AJOG (39.8%), Obstet Gynecol (9.7%), and J Matern Fetal Neonatal Med (6.5%). Publication rates were higher if the abstract’s first author was affiliated with a non-US institution (64.8% vs. 51.1%, p<0.001) and if the abstract received an award (82.7% vs. 53.3%, p<0.001). In regression models, oral presentation at SMFM, first author affiliation with a non-US institution, submission for AJOG SMFM special issue, and year of abstract presentation at SMFM were associated with full manuscript publication. Conclusions Between 2003 and 2010, full manuscript publication rates of SMFM abstracts were high and consistent, and time to publication decreased/improved across the study period for oral presentations. PMID:25981850

Study of 1-min rain rate integration statistic in South Korea

NASA Astrophysics Data System (ADS)

Shrestha, Sujan; Choi, Dong-You

2017-03-01

The design of millimeter wave communication links and the study of propagation impairments at higher frequencies due to a hydrometeor, particularly rain, require the knowledge of 1-min. rainfall rate data. Signal attenuation in space communication results are due to absorption and scattering of radio wave energy. Radio wave attenuation due to rain depends on the relevance of a 1-min. integration time for the rain rate. However, in practice, securing these data over a wide range of areas is difficult. Long term precipitation data are readily available. However, there is a need for a 1-min. rainfall rate in the rain attenuation prediction models for a better estimation of the attenuation. In this paper, we classify and survey the prominent 1-min. rain rate models. Regression analysis was performed for the study of cumulative rainfall data measured experimentally for a decade in nine different regions in South Korea, with 93 different locations, using the experimental 1-min. rainfall accumulation. To visualize the 1-min. rainfall rate applicable for the whole region for 0.01% of the time, we have considered the variation in the rain rate for 40 stations across South Korea. The Kriging interpolation method was used for spatial interpolation of the rain rate values for 0.01% of the time into a regular grid to obtain a highly consistent and predictable rainfall variation. The rain rate exceeded the 1-min. interval that was measured through the rain gauge compared to the rainfall data estimated using the International Telecommunication Union Radio Communication Sector model (ITU-R P.837-6) along with the empirical methods as Segal, Burgueno et al., Chebil and Rahman, logarithmic, exponential and global coefficients, second and third order polynomial fits, and Model 1 for Icheon regions under the regional and average coefficient set. The ITU-R P. 837-6 exhibits a lower relative error percentage of 3.32% and 12.59% in the 5- and 10-min. to 1-min. conversion, whereas the higher error percentages of 24.64%, 46.44% and 58.46% for the 20-, 30- and 60-min. to 1-min., conversion were obtained in the Icheon region. The available experimental rainfall data were sampled on equiprobable rain-rate values where the application of these models to experimentally obtained data exhibits a variable error rate. This paper aims to provide a better survey of various conversion methods to model a 1-min. rain rate applicable to the South Korea regions with a suitable contour plot at 0.01% of the time.

Effect of lipase immobilization on resolution of (R, S)-2-octanol in nonaqueous media using modified ultrastable-Y molecular sieve as support.

PubMed

Dai, Dazhang; Xia, Liming

2006-07-01

The lipase from Penicillium expansum PED-03 (PEL) was immobilized onto modified ultrastable-Y (USY) molecular sieve and the resolution of (R, S)- 2-octanol was carried out in a bioreactor in nonaqueous media by the immobilized lipase. It was found that the conversion rate, enantiomeric excess (ee) value, and enantioselectivity (E) value of the resolution catalyzed by PEL immobilized on modified USY molecular sieve were much higher than those of the reaction catalyzed by free PEL and PEL immobilized on other supports. Immobilized on modified USY molecular sieve, the PEL exhibited obvious activity within a wider pH range and at a much higher temperature and showed a markedly enhanced stability against thermal inactivation, by which the suitable pH of the buffer used for immobilization could be "memorized." The conversion rate of the reaction catalyzed by PEL immobilized on modified USY molecular sieve reached 48.84%, with excellent enantioselectivity (average E value of eight batches >460) in nonaqueous media at "memorial" pH 9.5, 50 degrees C for 24 h, demonstrating a good application potential in the production of optically pure (R, S)-2-octanol.

Unbuckling the Bible Belt: A State-Level Analysis of Religious Factors and Google Searches for Porn.

PubMed

Whitehead, Andrew L; Perry, Samuel L

2018-01-01

While the link between individual religious characteristics and pornography consumption is well established, relatively little research has considered how the wider religious context may influence pornography use. Exceptions in the literature to date have relied on relatively broad, subjective measures of religious commitment, largely ignoring issues of religious belonging, belief, or practice. This study moves the conversation forward by examining how a variety of state-level religious factors predict Google searches for the term porn, net of relevant sociodemog raphic and ideological controls. Our multivariate findings indicate that higher percentages of Evangelical Protestants, theists, and biblical literalists in a state predict higher frequencies of searching for porn, as do higher church attendance rates. Conversely, higher percentages of religiously unaffiliated persons in a state predict lower frequencies of searching for porn. Higher percentages of total religious adherents, Catholics, or mainline Protestants in a state are unrelated to searching for porn with controls in place. Contrary to recent research, our analyses also show that higher percentages of political conservatives in a state predicted lower frequencies of porn searches. Our findings support theories that more salient, traditional religious influences in a state may influence residents-whether religious or not-toward more covert sexual experiences.

Cardiorenal benefits of early versus late cyclosporine to sirolimus conversion in a rat model

PubMed Central

Sereno, José; Romão, Ana M.; Parada, Belmiro; Lopes, Patrícia; Carvalho, Eugénia; Teixeira, Frederico; Reis, Flávio

2012-01-01

Objective: To compare the cardiorenal effects of early versus late cyclosporine (CsA) to sirolimus (SRL) conversion, using a novel animal model that mimics these protocols used in the clinical practice, and focusing on blood pressure, heart rate (HR), biochemical data and heart and kidney lipid peroxidation. Materials and Methods: The study had five groups. Six male Wistar rats in each group were used during a 9-week study protocol: control, CsA (5 mg/kg/day), SRL (1 mg/kg/day); early conversion and late conversion. Cardiorenal evaluation was assessed by biochemical data, blood pressure, HR, and heart and kidney lipid peroxidation. Results: As expected, CsA promoted cardiorenal impairment, viewed by development of hypertension, tachycardia, increased urea, creatine kinase, and glucose levels, as well as heart and kidney oxidative stress. SRL, as expected, promoted less cardiorenal side effects, namely those related with nephrotoxicity. In agreement, both early and late conversions from CsA to SRL produced less side-effects, namely those related to the CsA-induced nephrotoxicity. Conclusions: In our model, both early and late CsA to SRL conversion promoted amelioration of the CsA -induced cardiorenal damage. However, early substitution seems to produce more benefits, in particular due to higher improvement of the cardiac profile. PMID:22629089

Quantifying risk of early relapse in patients with first demyelinating events: Prediction in clinical practice.

PubMed

Spelman, Tim; Meyniel, Claire; Rojas, Juan Ignacio; Lugaresi, Alessandra; Izquierdo, Guillermo; Grand'Maison, Francois; Boz, Cavit; Alroughani, Raed; Havrdova, Eva; Horakova, Dana; Iuliano, Gerardo; Duquette, Pierre; Terzi, Murat; Grammond, Pierre; Hupperts, Raymond; Lechner-Scott, Jeannette; Oreja-Guevara, Celia; Pucci, Eugenio; Verheul, Freek; Fiol, Marcela; Van Pesch, Vincent; Cristiano, Edgardo; Petersen, Thor; Moore, Fraser; Kalincik, Tomas; Jokubaitis, Vilija; Trojano, Maria; Butzkueven, Helmut

2017-09-01

Characteristics at clinically isolated syndrome (CIS) examination assist in identification of patient at highest risk of early second attack and could benefit the most from early disease-modifying drugs (DMDs). To examine determinants of second attack and validate a prognostic nomogram for individualised risk assessment of clinical conversion. Patients with CIS were prospectively followed up in the MSBase Incident Study. Predictors of clinical conversion were analysed using Cox proportional hazards regression. Prognostic nomograms were derived to calculate conversion probability and validated using concordance indices. A total of 3296 patients from 50 clinics in 22 countries were followed up for a median (inter-quartile range (IQR)) of 1.92 years (0.90, 3.71). In all, 1953 (59.3%) patients recorded a second attack. Higher Expanded Disability Status Scale (EDSS) at baseline, first symptom location, oligoclonal bands and various brain and spinal magnetic resonance imaging (MRI) metrics were all predictors of conversion. Conversely, older age and DMD exposure post-CIS were associated with reduced rates. Prognostic nomograms demonstrated high concordance between estimated and observed conversion probabilities. This multinational study shows that age at CIS onset, DMD exposure, EDSS, multiple brain and spinal MRI criteria and oligoclonal bands are associated with shorter time to relapse. Nomogram assessment may be useful in clinical practice for estimating future clinical conversion.

Mammalian keratin associated proteins (KRTAPs) subgenomes: disentangling hair diversity and adaptation to terrestrial and aquatic environments.

PubMed

Khan, Imran; Maldonado, Emanuel; Vasconcelos, Vítor; O'Brien, Stephen J; Johnson, Warren E; Antunes, Agostinho

2014-09-10

Adaptation of mammals to terrestrial life was facilitated by the unique vertebrate trait of body hair, which occurs in a range of morphological patterns. Keratin associated proteins (KRTAPs), the major structural hair shaft proteins, are largely responsible for hair variation. We exhaustively characterized the KRTAP gene family in 22 mammalian genomes, confirming the existence of 30 KRTAP subfamilies evolving at different rates with varying degrees of diversification and homogenization. Within the two major classes of KRTAPs, the high cysteine (HS) subfamily experienced strong concerted evolution, high rates of gene conversion/recombination and high GC content. In contrast, high glycine-tyrosine (HGT) KRTAPs showed evidence of positive selection and low rates of gene conversion/recombination. Species with more hair and of higher complexity tended to have more KRATP genes (gene expansion). The sloth, with long and coarse hair, had the most KRTAP genes (175 with 141 being intact). By contrast, the "hairless" dolphin had 35 KRTAPs and the highest pseudogenization rate (74% relative to the 19% mammalian average). Unique hair-related phenotypes, such as scales (armadillo) and spines (hedgehog), were correlated with changes in KRTAPs. Gene expression variation probably also influences hair diversification patterns, for example human have an identical KRTAP repertoire as apes, but much less hair. We hypothesize that differences in KRTAP gene repertoire and gene expression, together with distinct rates of gene conversion/recombination, pseudogenization and positive selection, are likely responsible for micro and macro-phenotypic hair diversification among mammals in response to adaptations to ecological pressures.

Lipase of Aspergillus niger NCIM 1207: A Potential Biocatalyst for Synthesis of Isoamyl Acetate.

PubMed

Mhetras, Nutan; Patil, Sonal; Gokhale, Digambar

2010-10-01

Commercial lipase preparations and mycelium bound lipase from Aspergillus niger NCIM 1207 were used for esterification of acetic acid with isoamyl alcohol to obtain isoamyl acetate. The esterification reaction was carried out at 30°C in n-hexane with shaking at 120 rpm. Initial reaction rates, conversion efficiency and isoamyl acetate concentration obtained using Novozyme 435 were the highest. Mycelium bound lipase of A. niger NCIM 1207 produced maximal isoamyl acetate formation at an alcohol/acid ratio of 1.6. Acetic acid at higher concentrations than required for the critical alcohol/acid ratio lower than 1.3 and higher than 1.6 resulted in decreased yields of isoamyl acetate probably owing to lowering of micro-aqueous environmental pH around the enzyme leading to inhibition of enzyme activity. Mycelium bound A. niger lipase produced 80 g/l of isoamyl acetate within 96 h even though extremely less amount of enzyme activity was used for esterification. The presence of sodium sulphate during esterification reaction at higher substrate concentration resulted in increased conversion efficiency when we used mycelium bound enzyme preparations of A. niger NCIM 1207. This could be due to removal of excess water released during esterification reaction by sodium sulphate. High ester concentration (286.5 g/l) and conversion (73.5%) were obtained within 24 h using Novozyme 435 under these conditions.

Improvement of L-valine production at high temperature in Brevibacterium flavum by overexpressing ilvEBNrC genes.

PubMed

Hou, Xiaohu; Ge, Xiangyang; Wu, Di; Qian, He; Zhang, Weiguo

2012-01-01

Brevibacterium flavum ATCC14067 was engineered for L: -valine production by overexpression of different ilv genes; the ilvEBN(r)C genes from B. flavum NV128 provided the best candidate for L: -valine production. In traditional fermentation, L: -valine production reached 30.08 ± 0.92 g/L at 31°C in 72 h with a low conversion efficiency of 0.129 g/g. To further improve the L: -valine production and conversion efficiency based on the optimum temperatures of L: -valine biosynthesis enzymes (above 35°C) and the thermotolerance of B. flavum, the fermentation temperature was increased to 34, 37, and 40°C. As a result, higher metabolic rate and L: -valine biosynthesis enzymes activity were obtained at high temperature, and the maximum L: -valine production, conversion efficiency, and specific L: -valine production rate reached 38.08 ± 1.32 g/L, 0.241 g/g, and 0.133 g g(-1) h(-1), respectively, at 37°C in 48 h fermentation. The strategy for enhancing L: -valine production by overexpression of key enzymes in thermotolerant strains may provide an alternative approach to enhance branched-chain amino acids production with other strains.

Solar Spectrum Photocatalytic Conversion of CO2 and Water Vapor Into Hydrocarbons Using TiO2 Nanoparticle Membranes

NASA Astrophysics Data System (ADS)

Rani, Sanju; Bao, Ningzhong; Roy, Somnath C.

2014-01-01

A viable option for recycling carbon dioxide is through the sunlight-powered photocatalytic conversion of CO2 and water vapor into hydrocarbon fuels over highly active nanocatalysts. With photocatalytic CO2 reduction sunlight, a renewable energy source as durable as the sun, is used to drive the catalytic reaction with the resultant fuel products compatible with the current hydrocarbon-based energy infrastructure. The use of co-catalyst (Cu, Pt)-sensitized TiO2 nanoparticle wafers in the photocatalytic conversion of CO2 and water vapor to hydrocarbon fuels, with optimal humidity levels and exposure times established. We also attempted to increase product formation by sputtering both co-catalysts on the nanoparticle wafer's surface, with the resulting product rates significantly higher than that of either the Cu or Pt coated samples. When the TiO2 nanoparticle wafers are used in a flow-through membrane implementation we find a significant increase in product rates of formation, including methane, hydrogen, and carbon monoxide. We believe that nanocatalyst-based flow-through membranes are a viable route for achieving large-scale and low cost photocatalytic solar fuel production.

5 CFR 534.406 - Conversion to the SES pay system.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 5 Administrative Personnel 1 2011-01-01 2011-01-01 false Conversion to the SES pay system. 534.406... UNDER OTHER SYSTEMS Pay and Performance Awards Under the Senior Executive Service § 534.406 Conversion... senior executive's converted rate of basic pay. Conversion to a new SES rate of basic pay is not...

Poor response cycles: when should we cancel? Comparison of outcome between egg collection, intrauterine insemination conversion, and follow-up cycles after abandonment.

PubMed

Nicopoullos, James D M; Abdalla, Hossam

2011-01-01

To determine optimal management with one or two mature follicles after stimulation. Retrospective analysis. Lister fertility clinic. A total of 1,350 IVF/intracytoplasmic sperm injection cycles (7.3% of total) during 1998-2009 were found to have one or two mature follicles. Group 1 (n = 807) comprised those who proceeded to vaginal egg collection (VEC) (59.8%; outcome per egg collection), group 2 (n=248) those who converted to IUI (18.4%; outcome per insemination) and group 3 (n=259) those who abandoned the current cycle (21.9%; outcome per abandoned cycle in first subsequent cycle). Live birth rate, clinical pregnancy rate, and biochemical pregnancy rate. Biochemical pregnancy rates of 13.1%, 4.9%, and 9.7%, clinical pregnancy rates of 8.1%, 3.6%, and 7.2%, and ongoing pregnancy rates of 6.8%, 2.0%, and 5.5% were achieved in groups 1, 2, and 3, respectively. All pregnancy outcomes were significantly higher after VEC (group 1) than for those converted to IUI (group 2), and all pregnancy outcomes were higher with borderline significance in group 3 vs. group 2. There was no significant difference in outcome between groups 1 and 3. Our data suggest that for such poor responders, proceeding to VEC may represent their best chance of successful outcome. Conversion to IUI offers the poorest outcome, and despite the potential for improvements in cycle protocol, abandoning and a further attempt does not improve outcome (using abandoned cycle as the denominator). Copyright © 2011 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Laparoscopic surgery for complicated diverticular disease: a single-centre experience.

PubMed

Royds, J; O'Riordan, J M; Eguare, E; O'Riordan, D; Neary, P C

2012-10-01

The role of laparoscopic surgery in the management of patients with diverticular disease is still not universally accepted. The aim of our study was to evaluate the results of laparoscopic surgery for diverticular disease in a centre with a specialist interest in minimally invasive surgery. All diverticular resections carried out between 2006 and 2010 were reviewed. Data recorded included baseline demographics, indication for surgery, operative details, length of hospital stay and complications. Complicated diverticular disease was defined as diverticulitis with associated abscess, phlegmon, fistula, stricture, obstruction, bleeding or perforation. One hundred and two patients (58 men) who had surgery for diverticular disease were identified (median age 59 years, range 49-70 years). Sixty-four patients (64%) had surgery for complicated diverticular disease. The indications were recurrent acute diverticulitis (37%), colovesical fistula (21%), stricture formation (17%) and colonic perforation (16%). Sixty-nine cases (88%) were completed by elective laparoscopy. Postoperative mortality was 0%. For elective cases there was no difference in morbidity rates between patients with complicated and uncomplicated diverticular disease. The overall anastomotic leakage rate was 1% and the wound infection rate 7%. There was a nonsignificant trend to higher conversion to open surgery in the elective group in complicated (11.4%) compared with uncomplicated patients (5.2%) (P=0.67). Electively, the rate of stoma formation was higher in the complicated (31.6%) than the uncomplicated group (5.2%) (P<0.02). Laparoscopic surgery for both complicated and uncomplicated diverticular disease is associated with low rates of postoperative morbidity and relatively low conversion rates. Laparoscopic surgery is now the standard of care for complicated and uncomplicated diverticular disease in our institution. © 2011 The Authors. Colorectal Disease © 2011 The Association of Coloproctology of Great Britain and Ireland.

Thermomyces lanuginosus lipase-catalyzed synthesis of natural flavor esters in a continuous flow microreactor.

PubMed

Gumel, Ahmad Mohammed; Annuar, M S M

2016-06-01

Enzymatic catalysis is considered to be among the most environmental friendly processes for the synthesis of fine chemicals. In this study, lipase from Thermomyces lanuginosus (Lecitase Ultra™) was used to catalyze the synthesis of flavor esters, i.e., methyl butanoate and methyl benzoate by esterification of the acids with methanol in a microfluidic system. Maximum reaction rates of 195 and 115 mM min -1 corresponding to catalytic efficiencies (k cat /K M ) of 0.30 and 0.24 min -1  mM -1 as well as yield conversion of 54 and 41 % were observed in methyl butanoate and methyl benzoate synthesis, respectively. Catalytic turnover (k cat ) was higher for methyl butanoate synthesis. Rate of synthesis and yield decreased with increasing flow rates. For both esters, increase in microfluidic flow rate resulted in increased advective transport over molecular diffusion and reaction rate, thus lower conversion. In microfluidic synthesis using T. lanuginosus lipase, the following reaction conditions were 40 °C, flow rate 0.1 mL min -1 , and 123 U g -1 enzyme loading found to be the optimum operating limits. The work demonstrated the application of enzyme(s) in a microreactor system for the synthesis of industrially important esters.

Adaptation of the autotrophic acetogen Sporomusa ovata to methanol accelerates the conversion of CO2 to organic products

PubMed Central

Tremblay, Pier-Luc; Höglund, Daniel; Koza, Anna; Bonde, Ida; Zhang, Tian

2015-01-01

Acetogens are efficient microbial catalysts for bioprocesses converting C1 compounds into organic products. Here, an adaptive laboratory evolution approach was implemented to adapt Sporomusa ovata for faster autotrophic metabolism and CO2 conversion to organic chemicals. S. ovata was first adapted to grow quicker autotrophically with methanol, a toxic C1 compound, as the sole substrate. Better growth on different concentrations of methanol and with H2-CO2 indicated the adapted strain had a more efficient autotrophic metabolism and a higher tolerance to solvent. The growth rate on methanol was increased 5-fold. Furthermore, acetate production rate from CO2 with an electrode serving as the electron donor was increased 6.5-fold confirming that the acceleration of the autotrophic metabolism of the adapted strain is independent of the electron donor provided. Whole-genome sequencing, transcriptomic, and biochemical studies revealed that the molecular mechanisms responsible for the novel characteristics of the adapted strain were associated with the methanol oxidation pathway and the Wood-Ljungdahl pathway of acetogens along with biosynthetic pathways, cell wall components, and protein chaperones. The results demonstrate that an efficient strategy to increase rates of CO2 conversion in bioprocesses like microbial electrosynthesis is to evolve the microbial catalyst by adaptive laboratory evolution to optimize its autotrophic metabolism. PMID:26530351

Sulfur resistance of Ce-Mn/TiO2 catalysts for low-temperature NH3–SCR

PubMed Central

Yang, Wenjing; Cui, Shitong; Street, Jason; Luo, Yan

2018-01-01

Ce-Mn/TiO2 catalyst prepared using a simple impregnation method demonstrated a better low-temperature selective catalytic reduction of NO with NH3 (NH3–SCR) activity in comparison with the sol-gel method. The Ce-Mn/TiO2 catalyst loading with 20% Ce had the best low-temperature activity and achieved a NO conversion rate higher than 90% at 140–260°C with a 99.7% NO conversion rate at 180°C. The Ce-Mn/TiO2 catalyst only had a 6% NO conversion rate decrease after 100 ppm of SO2 was added to the stream. When SO2 was removed from the stream, the catalyst was able to recover completely. The crystal structure, morphology, textural properties and valence state of the metals involving the novel catalysts were investigated using X-ray diffraction, N2 adsorption and desorption analysis, X-ray photoelectron spectroscopy, scanning electron microscopy and energy dispersive spectroscopy, respectively. The decrease of NH3–SCR performance in the presence of 100 ppm SO2 was due to the decrease of the surface area, change of the pore structure, the decrease of Ce4+ and Mn4+ concentration and the formation of the sulfur phase chemicals which blocked the active sites and changed the valence status of the elements. PMID:29657791

Sulfur resistance of Ce-Mn/TiO2 catalysts for low-temperature NH3-SCR

NASA Astrophysics Data System (ADS)

Xu, Quan; Yang, Wenjing; Cui, Shitong; Street, Jason; Luo, Yan

2018-03-01

Ce-Mn/TiO2 catalyst prepared using a simple impregnation method demonstrated a better low-temperature selective catalytic reduction of NO with NH3 (NH3-SCR) activity in comparison with the sol-gel method. The Ce-Mn/TiO2 catalyst loading with 20% Ce had the best low-temperature activity and achieved a NO conversion rate higher than 90% at 140-260°C with a 99.7% NO conversion rate at 180°C. The Ce-Mn/TiO2 catalyst only had a 6% NO conversion rate decrease after 100 ppm of SO2 was added to the stream. When SO2 was removed from the stream, the catalyst was able to recover completely. The crystal structure, morphology, textural properties and valence state of the metals involving the novel catalysts were investigated using X-ray diffraction, N2 adsorption and desorption analysis, X-ray photoelectron spectroscopy, scanning electron microscopy and energy dispersive spectroscopy, respectively. The decrease of NH3-SCR performance in the presence of 100 ppm SO2 was due to the decrease of the surface area, change of the pore structure, the decrease of Ce4+ and Mn4+ concentration and the formation of the sulfur phase chemicals which blocked the active sites and changed the valence status of the elements.

Laparoscopic appendectomy: Which factors are predictors of conversion? A high-volume prospective cohort study.

PubMed

Antonacci, Nicola; Ricci, Claudio; Taffurelli, Giovanni; Monari, Francesco; Del Governatore, Marco; Caira, Antonello; Leone, Antonio; Cervellera, Maurizio; Minni, Francesco; Cola, Bruno

2015-09-01

Appendicitis represents one of the most frequent condition requiring surgery. In Italy almost 0.2% of the population will be affected by acute appendicitis every year. Laparoscopic appendectomy (LA) has gained acceptance over the past years and despite several meta-analyses, randomized studies and retrospective studies have been conducted, the indications and results are still conflicting especially in cases of complicated appendicitis. The aim of our study is to evaluate which factors are related to conversion to open appendectomy (OA) during laparoscopic appendectomy (LA). From September 2011 to May 2013, appendectomy for acute appendicitis was performed on 434 patients in our Surgical Unit at S. Orsola-Malpighi Hospital, Bologna, Italy. Of these, 369 patients (85%) underwent LA. The clinical, demographic, surgical and pathological data of these patients were included in a prospective database. To note, only laparoscopic appendectomies were considered to be included in the analysis. The following factors were analyzed in order to identify which were associated with the conversion: age, sex, body mass index (BMI), previous abdominal surgery, comorbidities, clinical and laboratory parameters including Alvarado score, PCR, intraoperative findings such as anatomy and degree of inflammation. During our study period, laparoscopic appendectomies were performed by different surgeons both residents and attending surgeons. The decision to convert the intervention in an open procedure was taken by the individual surgeon. Regarding the postoperative period, were considered the time of hospitalization and related costs, time of oral intake of liquid and solid, time of passage of stool, readmissions and reoperations. At univariate analysis, the factors significantly related to the conversion were the presence of comorbidities (p < 0.001) and, among these, the presence of arterial hypertension (p = 0.006) or other cardiovascular diseases (p = 0.031) and the history of previous abdominal surgery (p = 0.023). Patients with higher mean age (33.9 ± 15.4 vs. 46.0 ± 19.3, p = 0.001) and higher body mass index (BMI) (23.5 ± 4.3 vs 25.8 ± 4.9 kg/m(2), p = 0.006) had a higher risk of conversion. Multivariate analysis finally showed that factors significantly related to the conversion were the presence of comorbidities (p = 0.029), the presence of an appendiceal perforation (p = 0.003), a retrocecal appendix (p = 0.004), the presence of appendicular abscess (p = 0.023) and the presence of diffuse peritonitis (p = 0.008). The majority of patients with acute appendicitis can be successfully managed with laparoscopy. We found that the only preoperative independent factor related to conversion during laparoscopic appendectomy is the presence of comorbidities. Nevertheless surgeons should take into account that presence of peri-appendicular abscess and diffuse peritonitis are both independently related not only to higher rate of conversion but also to higher risk of postoperative complication. Copyright © 2015 IJS Publishing Group Limited. Published by Elsevier Ltd. All rights reserved.

Synergetic and inhibition effects in carbon dioxide gasification of blends of coals and biomass fuels of Indian origin.

PubMed

Satyam Naidu, V; Aghalayam, P; Jayanti, S

2016-06-01

The present study investigates the enhancement of CO2 gasification reactivity of coals due to the presence of catalytic elements in biomass such as K2O, CaO, Na2O and MgO. Co-gasification of three Indian coal chars with two biomass chars has been studied using isothermal thermogravimetric analysis (TGA) in CO2 environment at 900, 1000 and 1100°C. The conversion profiles have been used to establish synergetic or inhibitory effect on coal char reactivity by the presence of catalytic elements in biomass char by comparing the 90% conversion time with and without biomass. It is concluded that both biomasses exhibit synergistic behavior when blended with the three coals with casuarina being more synergetic than empty fruit bunch. Some inhibitory effect has been noted for the high ash coal at the highest temperature with higher 90% conversion time for the blend over pure coal, presumably due to diffusional control of the conversion rate. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of sonication on co-precipitation synthesis and activity of copper manganese oxide catalyst to remove methane and sulphur dioxide gases.

PubMed

Yap, Yeow Hong; Lim, Mitchell S W; Lee, Zheng Yee; Lai, Kar Chiew; Jamaal, Muhamad Ashraf; Wong, Farng Hui; Ng, Hoon Kiat; Lim, Siew Shee; Tiong, T Joyce

2018-01-01

The utilisation of ultrasound in chemical preparation has been the focus of intense study in various fields, including materials science and engineering. This paper presents a novel method of synthesising the copper-manganese oxide (Hopcalite) catalyst that is used for the removal of volatile organic compounds and greenhouse gases like carbon monoxide. Several samples prepared under different conditions, with and without ultrasound, were subjected to a series of characterisation tests such as XRD, BET, FE-SEM, EDX, TPR-H 2 , TGA and FT-IR in order to establish their chemical and physical properties. A series of catalytic tests using a micro-reactor were subsequently performed on the samples in order to substantiate the aforementioned properties by analysing their ability to oxidise compressed natural gas (CNG), containing methane and sulphur dioxide. Results showed that ultrasonic irradiation of the catalyst led to observable alterations in its morphology: surfaces of the particles were noticeably smoothed and an increased in amorphicity was detected. Furthermore, ultrasonic irradiation has shown to enhance the catalytic activity of Hopcalite, achieving a higher conversion of methane relative to non-sonicated samples. Varying the ultrasonic intensity also produced appreciable effects, whereby an increase in intensity results in a higher conversion rate. The catalyst sonicated at the highest intensity of 29.7W/cm 2 has a methane conversion rate of 13.5% at 400°C, which was the highest among all the samples tested. Copyright © 2017 Elsevier B.V. All rights reserved.

Optimization of IVF pregnancy outcomes with donor spermatozoa.

PubMed

Wang, Jeff G; Douglas, Nataki C; Prosser, Robert; Kort, Daniel; Choi, Janet M; Sauer, Mark V

2009-03-01

To identify risk factors for suboptimal IVF outcomes using insemination with donor spermatozoa and to define a lower threshold that may signal a conversion to fertilization by ICSI rather than insemination. Retrospective, age-matched, case-control study of women undergoing non-donor oocyte IVF cycles using either freshly ejaculated (N=138) or cryopreserved donor spermatozoa (N=69). Associations between method of fertilization, semen sample parameters, and pregnancy rates were analyzed. In vitro fertilization of oocytes with donor spermatozoa by insemination results in equivalent fertilization and pregnancy rates compared to those of freshly ejaculated spermatozoa from men with normal semen analyses when the post-processing motility is greater than or equal to 88%. IVF by insemination with donor spermatozoa when the post-processing motility is less than 88% is associated with a 5-fold reduction in pregnancy rates when compared to those of donor spermatozoa above this motility threshold. When the post-processing donor spermatozoa motility is low, fertilization by ICSI is associated with significantly higher pregnancy rates compared to those of insemination. While ICSI does not need to be categorically instituted when using donor spermatozoa in IVF, patients should be counseled that conversion from insemination to ICSI may be recommended based on low post-processing motility.

Thermogravimetric study and kinetic analysis of fungal pretreated corn stover using the distributed activation energy model.

PubMed

Ma, Fuying; Zeng, Yelin; Wang, Jinjin; Yang, Yang; Yang, Xuewei; Zhang, Xiaoyu

2013-01-01

Non-isothermal thermogravimetry/derivative thermogravimetry (TG/DTG) measurements are used to determine pyrolytic characteristics and kinetics of lignocellulose. TG/DTG experiments at different heating rates with corn stover pretreated with monocultures of Irpex lacteus CD2 and Auricularia polytricha AP and their cocultures were conducted. Heating rates had little effect on the pyrolysis process, but the peak of weight loss rate in the DTG curves shifted towards higher temperature with heating rate. The maximum weight loss of biopretreated samples was 1.25-fold higher than that of the control at the three heating rates, and the maximum weight loss rate of the co-culture pretreated samples was intermediate between that of the two mono-cultures. The activation energies of the co-culture pretreated samples were 16-72 kJ mol(-1) lower than that of the mono-culture at the conversion rate range from 10% to 60%. This suggests that co-culture pretreatment can decrease activation energy and accelerate pyrolysis reaction thus reducing energy consumption. Copyright © 2012 Elsevier Ltd. All rights reserved.

Estimating forest conversion rates with annual forest inventory data

Treesearch

Paul C. Van Deusen; Francis A. Roesch

2009-01-01

The rate of land-use conversion from forest to nonforest or natural forest to forest plantation is of interest for forest certification purposes and also as part of the process of assessing forest sustainability. Conversion rates can be estimated from remeasured inventory plots in general, but the emphasis here is on annual inventory data. A new estimator is proposed...

High resolution A/D conversion based on piecewise conversion at lower resolution

DOEpatents

Terwilliger, Steve [Albuquerque, NM

2012-06-05

Piecewise conversion of an analog input signal is performed utilizing a plurality of relatively lower bit resolution A/D conversions. The results of this piecewise conversion are interpreted to achieve a relatively higher bit resolution A/D conversion without sampling frequency penalty.

Evaluation of correlation between glucan conversion and degree of delignification depending on pretreatment strategies using Jabon Merah.

PubMed

Jang, Soo-Kyeong; Jeong, Hanseob; Kim, Ho-Yong; Choi, June-Ho; Kim, Jong-Hwa; Koo, Bon-Wook; Choi, In-Gyu

2017-07-01

The main purpose of this study was to investigate the glucan conversion rate after enzymatic hydrolysis depending on the treatment methods and conditions with changes in the chemical composition of treated solid fraction of Jabon Merah. The glucan conversion rate (17.4%) was not significantly improved after liquid hot water treatment (1st step) even though most of the hemicellulose was dissolved into liquid hydrolysate. Subsequently, dilute acid, organosolv, and peracetic acid treatment (2nd step) was conducted under various conditions to enhance glucan conversion. Among the 2nd step treatment, the glucan conversion rate of organosolv (max. 46.0%) and peracetic acid treatment (max. 65.9%) was increased remarkably through decomposition of acid-insoluble lignin (AIL). Finally, the glucan conversion rate and AIL content were highly correlated, which was revealed by the R-squared value (0.84), but inhibitory factors including cellulose crystallinity must be considered for advanced glucan conversion from highly recalcitrant biomasses, such as Jabon Merah. Copyright © 2017 Elsevier Ltd. All rights reserved.

Absolute Position Encoders With Vertical Image Binning

NASA Technical Reports Server (NTRS)

Leviton, Douglas B.

2005-01-01

Improved optoelectronic patternrecognition encoders that measure rotary and linear 1-dimensional positions at conversion rates (numbers of readings per unit time) exceeding 20 kHz have been invented. Heretofore, optoelectronic pattern-recognition absoluteposition encoders have been limited to conversion rates <15 Hz -- too low for emerging industrial applications in which conversion rates ranging from 1 kHz to as much as 100 kHz are required. The high conversion rates of the improved encoders are made possible, in part, by use of vertically compressible or binnable (as described below) scale patterns in combination with modified readout sequences of the image sensors [charge-coupled devices (CCDs)] used to read the scale patterns. The modified readout sequences and the processing of the images thus read out are amenable to implementation by use of modern, high-speed, ultra-compact microprocessors and digital signal processors or field-programmable gate arrays. This combination of improvements makes it possible to greatly increase conversion rates through substantial reductions in all three components of conversion time: exposure time, image-readout time, and image-processing time.

The impact of MRI steady-state sequences as an additional assessment modality in vestibular schwannoma patients after LINAC stereotactic radiotherapy or radiosurgery.

PubMed

Sauer, Julian P; Kinfe, Thomas M; Pintea, Bogdan; Schäfer, Andreas; Boström, Jan P

2018-05-23

Data concerning the clinical usefulness of steady-state sequences (SSS) for vestibular schwannomas (VS) after linear accelerator (LINAC) stereotactic radiosurgery (SRS) or stereotactic radiotherapy (SRT) are scarce. The aim of the study was to investigate whether SSS provide an additional useful follow-up (FU) tool to the established thin-layered T1 sequences with contrast enhancement. Pre- and post-treatment SSS were identified in 45 consecutive VS patients (2012-2016) with a standardized FU protocol including SSS at 2-3 months and 6 months/yearly in our prospective database and were retrospectively re-evaluated. The SSS were used throughout for the segmentation of the cochlea and partly of the trigeminal nerve in the treatment planning. Data analysis included signal conversion in SSS and possible correlation with neuro-otological outcome and volumetric assessment after a certain time interval. The series included 42 SRS and 3 SRT patients (31 female/14 male; mean age 59.3 years, range: 25-81 years). An SSS signal conversion was observed in 20 tumors (44.4%) within a mean time of 11 months (range: 7-15 months). Mean FU time was 26 months (median of 4 FU visits) and demonstrated tumor volume shrinkage in 29 cases (64.4%) correlating with FU time (p = 0.07). The incidence rate of combined shrinkage and signal conversion (48.3%) compared to those without signal conversion (51.7%) did not differ significantly (p = 0.49). In case of an early signal conversion at the first FU, a weak statistical significance (p = 0.05) for a higher shrinkage rate of VS with signal conversion was found. Side effects in cases with signal conversion (9/20, 45%) were more frequently than without signal conversion (6/25, 24%) without reaching statistical significance (p = 0.13). Our data confirmed the usefulness of SSS for anatomical segmentation of VS in LINAC-SRS/SRT treatment planning and add data supporting their potential as an adjunctive FU option in VS patients.

Benefits from Tween during enzymic hydrolysis of corn stover

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kaar, W.E.; Holtzapple, M.T.

1998-08-20

Corn stover is a potential substrate for fermentation processes. Previous work with corn stover demonstrated that lime pretreatment rendered it digestible by cellulase; however, high sugar yields required very high enzyme loadings. Because cellulase is a significant cost in biomass conversion processes, the present study focused on improving the enzyme efficiency using Tween 20 and Tween 80; Tween 20 is slightly more effective than Tween 80. The recommended pretreatment conditions for the biomass remained unchanged regardless of whether Tween was added during the hydrolysis. The recommended Tween loading was 0.15 g Tween/g dry biomass. The critical relationship was the Tweenmore » loading on the biomass, not the Tween concentration in solution. The 72-h enzymic conversion of pretreated corn stover using 5 FPU cellulase/g dry biomass at 50 C with Tween 20 as part of the medium was 0.85 g/g for cellulose, 0.66 g/g for xylan, and 0.75 for total polysaccharide; addition of Tween improved the cellulose, xylan, and total polysaccharide conversions by 42, 40, and 42%, respectively. Kinetic analyses showed that Tween improved the enzymic absorption constants, which increased the effective hydrolysis rate compared to hydrolysis without Tween. Furthermore, Tween prevented thermal deactivation of the enzymes, which allows for the kinetic advantage of higher temperature hydrolysis. Ultimate digestion studies showed higher conversions for samples containing Tween, indicating a substrate effect. It appears that Tween improves corn stover hydrolysis through three effects: enzyme stabilizer, lignocellulose disrupter, and enzyme effector.« less

Rate and predictors of conversion from unipolar to bipolar disorder: A systematic review and meta-analysis.

PubMed

Kessing, Lars Vedel; Willer, Inge; Andersen, Per Kragh; Bukh, Jens Drachman

2017-08-01

For the first time to present a systematic review and meta-analysis of the conversion rate and predictors of conversion from unipolar disorder to bipolar disorder. A systematic literature search up to October 2016 was performed. For the meta-analysis, we only included studies that used survival analysis to estimate the conversion rate. A total of 31 studies were identified, among which 11 used survival analyses, including two register-based studies. The yearly rate of conversion to bipolar disorder decreased with time from 3.9% in the first year after study entry with a diagnosis of unipolar disorder to 3.1% in years 1-2, 1.0% in years 2-5 and 0.8% in years 5-10. A total of eight risk factors were evaluated comprising gender, age at onset of unipolar disorder, number of depressive episodes, treatment resistance to antidepressants, family history of bipolar disorder, the prevalence of psychotic depression, the prevalence of chronic depression, and severity of depression. It was not possible to identify risk factors that were consistently or mainly confirmed to predict conversion across studies. The conversion rate from unipolar to bipolar disorder decreases with time. It was not possible to identify predictors of conversion that were consistently or mainly confirmed across studies, which may be due to variations in methodology across studies. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Strategies for the Evolution of Sex

NASA Astrophysics Data System (ADS)

Erzan, Ayse

2002-03-01

Using a bit-string model of evolution we find a successful route to diploidy and sex in simple organisms, for a step-like fitness function. Assuming that an excess of deleterious mutations triggers the conversion of haploids to diploidy and sex, we find that only one pair of sexual organisms can take over a finite population, if they engage in sexual reproduction under unfavorable conditions, and otherwise perform mitosis. Then, a haploid-diploid (HD) cycle is established, with an abbreviated haploid phase, as in present day sexual reproduction. If crossover is allowed during meiosis, HD cycles of arbitrary duration can be maintained. We find that the sexual population has a higher mortality rate than asexual diploids, but also a relaxation rate that is an order of magnitude higher. As a result, sexuals have a higher adaptability and lower mutational load on the average, since they can select out the undesirable genes much faster.

Bacterial Phenotype Variants in Group B Streptococcal Toxic Shock Syndrome1

PubMed Central

Johansson, Linda; Dahesh, Samira; Van Sorge, Nina M.; Darenberg, Jessica; Norgren, Mari; Sjölin, Jan; Nizet, Victor; Norrby-Teglund, Anna

2009-01-01

We conducted genetic and functional analyses of isolates from a patient with group B streptococcal (GBS) necrotizing fasciitis and toxic shock syndrome. Tissue cultures simultaneously showed colonies with high hemolysis (HH) and low hemolysis (LH). Conversely, the HH and LH variants exhibited low capsule (LC) and high capsule (HC) expression, respectively. Molecular analysis demonstrated that the 2 GBS variants were of the same clonal origin. Genetic analysis found a 3-bp deletion in the covR gene of the HH/LC variant. Functionally, this isolate was associated with an increased growth rate in vitro and with higher interleukin-8 induction. However, in whole blood, opsonophagocytic and intracellular killing assays, the LH/HC phenotype demonstrated higher resistance to host phagocytic killing. In a murine model, LH/HC resulted in higher levels of bacteremia and increased host mortality rate. These findings demonstrate differences in GBS isolates of the same clonal origin but varying phenotypes. PMID:19193266

Bacterial phenotype variants in group B streptococcal toxic shock syndrome.

PubMed

Sendi, Parham; Johansson, Linda; Dahesh, Samira; Van-Sorge, Nina M; Darenberg, Jessica; Norgren, Mari; Sjölin, Jan; Nizet, Victor; Norrby-Teglund, Anna

2009-02-01

We conducted genetic and functional analyses of isolates from a patient with group B streptococcal (GBS) necrotizing fasciitis and toxic shock syndrome. Tissue cultures simultaneously showed colonies with high hemolysis (HH) and low hemolysis (LH). Conversely, the HH and LH variants exhibited low capsule (LC) and high capsule (HC) expression, respectively. Molecular analysis demonstrated that the 2 GBS variants were of the same clonal origin. Genetic analysis found a 3-bp deletion in the covR gene of the HH/LC variant. Functionally, this isolate was associated with an increased growth rate in vitro and with higher interleukin-8 induction. However, in whole blood, opsonophagocytic and intracellular killing assays, the LH/HC phenotype demonstrated higher resistance to host phagocytic killing. In a murine model, LH/HC resulted in higher levels of bacteremia and increased host mortality rate. These findings demonstrate differences in GBS isolates of the same clonal origin but varying phenotypes.

5 CFR 531.221 - Maximum payable rate rule.

Code of Federal Regulations, 2010 CFR

2010-01-01

... before the reassignment. (ii) If the rate resulting from the geographic conversion under paragraph (c)(2... previous rate (i.e., the former special rate after the geographic conversion) with the rates on the current... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Maximum payable rate rule. 531.221...

Kinetic aspects of chain growth in Fischer-Tropsch synthesis.

PubMed

Filot, Ivo A W; Zijlstra, Bart; Broos, Robin J P; Chen, Wei; Pestman, Robert; Hensen, Emiel J M

2017-04-28

Microkinetics simulations are used to investigate the elementary reaction steps that control chain growth in the Fischer-Tropsch reaction. Chain growth in the FT reaction on stepped Ru surfaces proceeds via coupling of CH and CR surface intermediates. Essential to the growth mechanism are C-H dehydrogenation and C hydrogenation steps, whose kinetic consequences have been examined by formulating two novel kinetic concepts, the degree of chain-growth probability control and the thermodynamic degree of chain-growth probability control. For Ru the CO conversion rate is controlled by the removal of O atoms from the catalytic surface. The temperature of maximum CO conversion rate is higher than the temperature to obtain maximum chain-growth probability. Both maxima are determined by Sabatier behavior, but the steps that control chain-growth probability are different from those that control the overall rate. Below the optimum for obtaining long hydrocarbon chains, the reaction is limited by the high total surface coverage: in the absence of sufficient vacancies the CHCHR → CCHR + H reaction is slowed down. Beyond the optimum in chain-growth probability, CHCR + H → CHCHR and OH + H → H 2 O limit the chain-growth process. The thermodynamic degree of chain-growth probability control emphasizes the critical role of the H and free-site coverage and shows that at high temperature, chain depolymerization contributes to the decreased chain-growth probability. That is to say, during the FT reaction chain growth is much faster than chain depolymerization, which ensures high chain-growth probability. The chain-growth rate is also fast compared to chain-growth termination and the steps that control the overall CO conversion rate, which are O removal steps for Ru.

Conversion of spin current into charge current in a topological insulator: Role of the interface

NASA Astrophysics Data System (ADS)

Dey, Rik; Prasad, Nitin; Register, Leonard F.; Banerjee, Sanjay K.

2018-05-01

Three-dimensional spin current density injected onto the surface of a topological insulator (TI) produces a two-dimensional charge current density on the surface of the TI, which is the so-called inverse Edelstein effect (IEE). The ratio of the surface charge current density on the TI to the spin current density injected across the interface defined as the IEE length was shown to be exactly equal to the mean free path in the TI determined to be independent of the electron transmission rate across the interface [Phys. Rev. B 94, 184423 (2016), 10.1103/PhysRevB.94.184423]. However, we find that the transmission rate across the interface gives a nonzero contribution to the transport relaxation rate in the TI as well as to the effective IEE relaxation rate (over and above any surface hybridization effects), and the IEE length is always less than the original mean free path in the TI without the interface. We show that both the IEE relaxation time and the transport relaxation time in the TI are modified by the interface transmission time. The correction becomes significant when the transmission time across the interface becomes comparable to or less than the original momentum scattering time in the TI. This correction is similar to experimental results in Rashba electron systems in which the IEE relaxation time was found shorter in the case of direct interface with metal in which the interface transmission rate will be much higher, compared to interfaces incorporating insulating oxides. Our results indicate the continued importance of the interface to obtain a better spin-to-charge current conversion and a limitation to the conversion efficiency due to the quality of the interface.

Generation of µW level plateau harmonics at high repetition rate.

PubMed

Hädrich, S; Krebs, M; Rothhardt, J; Carstens, H; Demmler, S; Limpert, J; Tünnermann, A

2011-09-26

The process of high harmonic generation allows for coherent transfer of infrared laser light to the extreme ultraviolet spectral range opening a variety of applications. The low conversion efficiency of this process calls for optimization or higher repetition rate intense ultrashort pulse lasers. Here we present state-of-the-art fiber laser systems for the generation of high harmonics up to 1 MHz repetition rate. We perform measurements of the average power with a calibrated spectrometer and achieved µW harmonics between 45 nm and 61 nm (H23-H17) at a repetition rate of 50 kHz. Additionally, we show the potential for few-cycle pulses at high average power and repetition rate that may enable water-window harmonics at unprecedented repetition rate. © 2011 Optical Society of America

Comparisons of childhood trauma, alexithymia, and defensive styles in patients with psychogenic non-epileptic seizures vs. epilepsy: Implications for the etiology of conversion disorder.

PubMed

Kaplan, Marcia J; Dwivedi, Alok K; Privitera, Michael D; Isaacs, Kelly; Hughes, Cynthia; Bowman, Michelle

2013-08-01

It has been theorized that conversion disorder is the result of emotion that cannot be experienced consciously as feeling states or put into words (i.e., alexithymia), but there is little confirming empirical evidence. We sought to characterize subjects with conversion disorder compared to subjects with a distinct medical illness, using the model of psychogenic non-epileptic seizures (PNES) vs. epilepsy (ES), on measures of childhood traumatic experience, alexithymia and maturity of psychological defensive strategies. All subjects admitted to the Epilepsy Monitoring Unit of the University of Cincinnati Medical Center were offered self-report questionnaires (Childhood Trauma Questionnaire, Toronto Alexithymia Scale-20 and Response Evaluation Measure-71) at the outset of evaluation. Diagnosis of each subject was confirmed by video-EEG and we compared subjects with PNES to those with ES on these measures. 82 subjects had ES AND 96 had PNES. Those with PNES were significantly more likely to have experienced childhood trauma in all domains (p=.005 to p=.05), and were significantly more likely to have alexithymia (p=.0267). There was a significant difference in the capacity to identify feelings, and a trend towards significance in capacity to describe feelings. There were no differences in defensive styles between the two groups. PNES diagnosis was associated with female sex, higher alexithymia scores and higher rates of childhood trauma, but not with differences in defensive styles compared to ES. These findings add empirical evidence for theories regarding the cause of conversion disorder and may aid in the design of prospective treatment trials in patients with conversion disorder. Copyright © 2013 Elsevier Inc. All rights reserved.

Informed decision-making in elective major vascular surgery: analysis of 145 surgeon-patient consultations.

PubMed

Etchells, Edward; Ferrari, Michel; Kiss, Alex; Martyn, Nikki; Zinman, Deborah; Levinson, Wendy

2011-06-01

Prior studies show significant gaps in the informed decision-making process, a central goal of surgical care. These studies have been limited by their focus on low-risk decisions, single visits rather than entire consultations, or both. Our objectives were, first, to rate informed decision-making for major elective vascular surgery based on audiotapes of actual physician-patient conversations and, second, to compare ratings of informed decision-making for first visits to ratings for multiple visits by the same patient over time. We prospectively enrolled patients for whom vascular surgical treatment was a potential option at a tertiary care outpatient vascular surgery clinic. We audio-taped all surgeon-patient conversations, including multiple visits when necessary, until a decision was made. Using an existing method, we evaluated the transcripts for elements of decision-making, including basic elements (e.g., an explanation of the clinical condition), intermediate elements (e.g., risks and benefits) and complex elements (e.g., uncertainty around the decision). We analyzed 145 surgeon-patient consultations. Overall, 45% of consultations contained complex elements, whereas 23% did not contain the basic elements of decision-making. For the 67 consultations that involved multiple visits, ratings were significantly higher when evaluating all visits (50% complex elements) compared with evaluating only the first visit (33% complex elements, p < 0.001.) We found that 45% of consultations contained complex elements, which is higher than prior studies with similar methods. Analyzing decision-making over multiple visits yielded different results than analyzing decision-making for single visits.

Methane combustion reactivity during the metal→metallic oxide transformation of Pd-Pt catalysts: Effect of oxygen pressure

NASA Astrophysics Data System (ADS)

Qi, Wenjie; Ran, Jingyu; Zhang, Zhien; Niu, Juntian; Zhang, Peng; Fu, Lijuan; Hu, Bo; Li, Qilai

2018-03-01

Density functional theory combined with kinetic models were used to probe different kinetics consequences by which methane activation on different oxygen chemical potential surfaces as oxygen pressure increased. The metallic oxide → metal transformation temperature of Pd-Pt catalysts increased with the increase of the Pd content or/and O2 pressure. The methane conversion rate on Pt catalyst increased and then decreased to a constant value when increasing the O2 pressure, and Pd catalyst showed a poor activity performance in the case of low O2 pressure. Moreover, its activity increased as the oxygen chemical potential for O2 pressure increased in the range of 2.5-10 KPa. For metal clusters, the Csbnd H bond and Odbnd O bond activation steps occurred predominantly on *-* site pairs. The methane conversion rate was determined by O2 pressure because the adsorbed O atoms were rapidly consumed by other adsorbed species in this kinetic regime. As the O2 pressure increased, the metallic active sites for methane activation were decreased and there was no longer lack of adsorbed O atoms, resulting in the decrease of the methane conversion rate. Furthermore, when the metallic surfaces were completely covered by adsorbed oxygen atoms at higher oxygen chemical potentials, Pt catalyst showed a poor activity due to a high Csbnd H bond activation barrier on O*sbnd O*. In the case of high O2 pressure, Pd atoms preferred to segregate to the active surface of Pd-Pt catalysts, leading to the formation of PdO surfaces. The increase of Pd segregation promoted a subsequent increase in active sites and methane conversion rate. The PdO was much more active than metallic and O* saturated surfaces for methane activation, inferred from the theory and experimental study. Pd-rich bimetallic catalyst (75% molar Pd) showed a dual high methane combustion activity on O2-poor and O2-rich conditions.

Update on Electronic Dental Record and Clinical Computing Adoption Among Dental Practices in the United States

PubMed Central

Schroeder, Dixie; Schwei, Kelsey; Chyou, Po-Huang

2017-01-01

This study sought to re-characterize trends and factors affecting electronic dental record (EDR) and technologies adoption by dental practices and the impact of the Health Information Technology for Economic and Clinical Health (HITECH) act on adoption rates through 2012. A 39-question survey was disseminated nationally over 3 months using a novel, statistically-modeled approach informed by early response rates to achieve a predetermined sample. EDR adoption rate for clinical support was 52%. Adoption rates were higher among: (1) younger dentists; (2) dentists ≤ 15 years in practice; (3) females; and (4) group practices. Top barriers to adoption were EDR cost/expense, cost-benefit ratio, electronic format conversion, and poor EDR usability. Awareness of the Federal HITECH incentive program was low. The rate of chairside computer implementation was 72%. Adoption of EDR in dental offices in the United States was higher in 2012 than electronic health record adoption rates in medical offices and was not driven by the HITECH program. Patient portal adoption among dental practices in the United States remained low. PMID:29229631

Laparoscopic colectomy in the obese, morbidly obese, and super morbidly obese: when does weight matter?

PubMed

Champagne, Bradley J; Nishtala, Madhuri; Brady, Justin T; Crawshaw, Benjamin P; Franklin, Morris E; Delaney, Conor P; Steele, Scott R

2017-10-01

Previous studies have demonstrated that obese patients (BMI >30) undergoing laparoscopic colectomy have longer operative times and increased complications when compared to non-obese cohorts. However, there is little data that specifically evaluates the outcomes of obese patients based on the degree of their obesity. The aim of this study was to evaluate the impact of increasing severity of obesity on patients undergoing laparoscopic colectomy. A retrospective review was performed of all patients undergoing laparoscopic colectomy between 1996 and 2013. Patients were classified according to their BMI as obese (BMI 30.0-39.9), morbidly obese (BMI 40.0-49.9), and super obese (BMI >50). Main outcome measures included conversion rate, operative time, estimated blood loss, post-operative complications, and length of stay. There were 923 patients who met inclusion criteria. Overall, 604 (65.4%), 257 (27.9%), and 62 (6.7%) were classified as obese (O), morbidly obese (MO), and super obese (SO), respectively. Clinicopathologic characteristics were similar among the three groups. The SO group had significantly higher conversion rates (17.7 vs. 7 vs. 4.8%; P = 0.031), longer average hospital stays (7.1 days vs. 4.9 vs. 3.4; P = 0.001), higher morbidity (40.3 vs. 16.3 vs. 12.4%; P = 0.001), and longer operative times (206 min vs. 184 vs. 163; P = 0.04) compared to the MO and O groups, respectively. The anastomotic leak rate in the SO (4.8%; P = 0.027) and MO males (4.1%; P = 0.033) was significantly higher than MO females (2.2%) and all obese patients (1.8%). Increasing severity of obesity is associated with worse perioperative outcomes following laparoscopic colectomy.

Radiation resistant PIDECα cell using photon intermediate direct energy conversion and a 210Po source.

PubMed

Weaver, Charles L; Schott, Robert J; Prelas, Mark A; Wisniewski, Denis A; Rothenberger, Jason B; Lukosi, Eric D; Oh, Kyuhak

2018-02-01

Radiation damage is a significant concern with both alphavoltaic and betavoltaic cells because their performance degrades, especially with high-energy - (>200keV) beta and alpha particles. Indirect excitation methods, such as the Photon Intermediate Direct Energy Conversion (PIDEC) framework, can protect the transducer from radiation. A nuclear battery using a 90 Sr beta source was constructed by the author's research group, which demonstrated the radiation resistance of a PIDEC cell driven by beta particles (PIDECβ cell). Use of alpha sources to drive nuclear batteries would appear to be much more attractive than beta sources due to higher potential power density. However, they are also subject to higher rates of radiation damage. This paper describes the successful incorporation of alpha particles into the PIDEC framework using the alpha emitter 210 Po to form a PIDECα cell. The PIDECα cell transducer was exposed to alpha particles for over one year without experiencing adverse effects from radiation damage. Copyright © 2017 Elsevier Ltd. All rights reserved.

Investigation of the promoting effect of Mn on a Pt/C catalyst for the steam and aqueous phase reforming of glycerol

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bossola, Filippo; Pereira-Hernández, Xavier Isidro; Evangelisti, Claudio

2017-05-01

The catalytic performances in steam reforming (SR) and aqueous phase reforming (APR) of glycerol of a bimetallic Pt-Mn catalyst supported on activated carbon are investigated and correlated with the surface properties of the catalyst. Under SR conditions, Mn showed a significant promoting effect over Pt/C, both in terms of hydrogen production rate and conversion, with a higher selectivity toward the glycerol dehydration products. Upon addition of Mn the amount of strong Lewis acid sites increased, promoting the dehydration of glycerol and favoring the CAO over CAC cleavage at expenses of hydrogen selectivity. Conversely, under APR conditions, a slightly higher hydrogenmore » selectivity and only minimal enhancement in hydrogen production were found, while the products selectivity was comparable to Pt/C. Most of Mn leached into the aqueous media, but the remaining (<5% of the fresh parent sample) might be alloyed with Pt and promote the CO desorption from neighbor Pt sites.« less

How to Overcome Numerical Challenges to Modeling Stirling Engines

NASA Technical Reports Server (NTRS)

Dyson, Rodger W.; Wilson, Scott D.; Tew, Roy C.

2004-01-01

Nuclear thermal to electric power conversion carries the promise of longer duration missions and higher scientific data transmission rates back to Earth for a range of missions, including both Mars rovers and deep space missions. A free-piston Stirling convertor is a candidate technology that is considered an efficient and reliable power conversion device for such purposes. While already very efficient, it is believed that better Stirling engines can be developed if the losses inherent in current designs could be better understood. However, they are difficult to instrument and so efforts are underway to simulate a complete Stirling engine numerically. This has only recently been attempted and a review of the methods leading up to and including such computational analysis is presented. And finally it is proposed that the quality and depth of Stirling loss understanding may be improved by utilizing the higher fidelity and efficiency of recently developed numerical methods. One such method, the Ultra HI-FI technique is presented in detail.

Revisiting the diffusion approximation to estimate evolutionary rates of gene family diversification.

PubMed

Gjini, Erida; Haydon, Daniel T; David Barry, J; Cobbold, Christina A

2014-01-21

Genetic diversity in multigene families is shaped by multiple processes, including gene conversion and point mutation. Because multi-gene families are involved in crucial traits of organisms, quantifying the rates of their genetic diversification is important. With increasing availability of genomic data, there is a growing need for quantitative approaches that integrate the molecular evolution of gene families with their higher-scale function. In this study, we integrate a stochastic simulation framework with population genetics theory, namely the diffusion approximation, to investigate the dynamics of genetic diversification in a gene family. Duplicated genes can diverge and encode new functions as a result of point mutation, and become more similar through gene conversion. To model the evolution of pairwise identity in a multigene family, we first consider all conversion and mutation events in a discrete manner, keeping track of their details and times of occurrence; second we consider only the infinitesimal effect of these processes on pairwise identity accounting for random sampling of genes and positions. The purely stochastic approach is closer to biological reality and is based on many explicit parameters, such as conversion tract length and family size, but is more challenging analytically. The population genetics approach is an approximation accounting implicitly for point mutation and gene conversion, only in terms of per-site average probabilities. Comparison of these two approaches across a range of parameter combinations reveals that they are not entirely equivalent, but that for certain relevant regimes they do match. As an application of this modelling framework, we consider the distribution of nucleotide identity among VSG genes of African trypanosomes, representing the most prominent example of a multi-gene family mediating parasite antigenic variation and within-host immune evasion. © 2013 Published by Elsevier Ltd. All rights reserved.

Metal Nanoshells for Plasmonically Enhanced Solar to Fuel Photocatalytic Conversion

DTIC Science & Technology

2016-05-18

interlayer of ~17 nm generated a rate of hydrogen production 2.6 times higher than that of unmodified ZIS. Second thrust: Tin oxide-coated gold-silver...nanoshells were prepared as an alternative plasmonic enhancement system to the silicon oxide system described above. Tin oxide is an attractive...this grant, we developed two synthetic approaches for preparing tin oxide-coated gold-silver nanoshells, as illustrated in Scheme 2. These particles

Metal Nanoshells for Plasmonically Enhanced Solar to Fuel Photocatalytic Conversion

DTIC Science & Technology

2016-05-18

but are still under development. Scheme 2. Strategy for the Synthesis of Tin Oxide-Coated Gold- Silver Nanoshells Publication List: 1. Li, C.-H...DISTRIBUTION/AVAILABILITY STATEMENT A DISTRIBUTION UNLIMITED: PB Public Release 13. SUPPLEMENTARY NOTES 14. ABSTRACT First thrust: Gold- silver nanoshells...interlayer of ~17 nm generated a rate of hydrogen production 2.6 times higher than that of unmodified ZIS. Second thrust: Tin oxide-coated gold- silver

Effect of initiator concentration to low-density polyethylene production in a tubular reactor

NASA Astrophysics Data System (ADS)

Azmi, A.; Aziz, N.

2016-11-01

Low-density polyethylene (LDPE) is one of the most widely used polymers in the world, which is produced in high-capacity tubular and autoclave reactors. As the LDPE industry turn into more competitive and its market profit margins become tighter, manufacturers have to develop solutions to debottleneck the reactor output while abiding to the stringent product specification. A single polyolefin plant producing ten to forty grades of LDPE with various melt flow index (MFI), therefore understanding the reaction mechanism, the operating conditions as well as the dynamic behavior of tubular reactor is essential before any improvement can take place. In the present work, a steady state mathematical model representing a tubular reactor for the production of LDPE is simulated using MATLAB R2015a®. The model developed is a function of feed inlet, reactor jacket, single initiator injector and outlet stream. Analysis on the effect of initiator concentration (CI) shows sudden declining trend of initiator's concentration which indicates that all of the initiators are exhausted after polymerization reaction and no further reaction occur from this point onwards. Furthermore, the results demonstrate that the concentration of initiator gives significant impact on reactor temperature's profile and monomer conversion rate, since higher initiator concentration promotes greater polymerization rate, and therefore leads to higher monomer conversion throughput.

Enhanced compositing of radiation disinfected sewage sludge

NASA Astrophysics Data System (ADS)

Kawakami, W.; Hashimoto, S.

Studies on isothermal composting of radiation disinfected sewage sludge and liquid chromatography of water extracts of the products were carried out. The optimum temperature and pH were around 50 °C and 7-8, respectively. The repeated use of products as seeds increased the rate of CO 2 evolution. The rate reached a maximum within 10 hours and decreased rapidly, and the CO 2 evolution ceased after about 3 days. The conversion of organic carbon to carbon dioxide attained to about 40% for the repeated use of products as seeds at the optimum conditions. As long as seeds in available were used, no remarkable difference was found in the composting of unirradiated and irradiated sludges. The composting process using radiation, however, can be carried out at the optimum conditions and is expected to shorten the composting period, because it is not necessary to keep fermentation temperature higher to reduce pathogen in sludge. Liquid chromatographic studies of the products showed that low molecular components decreased and higher molecular ones increased with fermentation. An index expressing the degree of reduction of easily decomposable organics was presented. The index also showed that the optimum temperature for fermentation was 50 °C, and that the easily decomposable organics disappeared above 30% of the conversion of organic carbon.

Safety Outcomes of NOTES Cholecystectomy Versus Laparoscopic Cholecystectomy: A Systematic Review and Meta-Analysis

PubMed Central

Peng, Cheng; Ling, Yan; Ma, Chi; Ma, Xiaochun; Fan, Wei; Niu, Weibo

2016-01-01

Objective: Natural orifice transluminal endoscopic surgery (NOTES) is an endoscopic technique whereby surgical interventions can be performed with a flexible endoscope passed through a natural orifice (mouth, vulva, urethra, anus) then through a transluminal opening of the stomach, vagina, bladder, or colon. Although in the early stage of research and development, NOTES has been clinically applied across the globe, above all the transvaginal cholecystectomy is among the most frequently performed procedures. In the existing 2 types of transvaginal routes, the hybrid NOTES cholecystectomy (NC) is more likely to be accepted. However, there has been controversy regarding the safety outcomes of hybrid NC in comparison with classical laparoscopic cholecystectomy (LC). The primary objective of this meta-analysis is to compare the characteristics between NC and classical LC. Materials and Methods: A meta-analysis of eligible studies comparing NC with classical LC was performed to evaluate the safety outcomes including wound complications, other postoperative complications and intraoperative conversion between the 2 groups. Results: Pooling 3 randomized controlled trials (n=157) and 7 nonrandomized trial (n=593) demonstrated that the rates of wound complications and other postoperative complications in NC group did not significantly differ from those of classical LC group [wound complications: ratio difference (RD)=−0.02, 95% confidence interval (CI) −0.04to 0.01, P=0.23; other postoperative complication: RD=−0.01; 95% CI, −0.03 to 0.02; P=0.6]. The intraoperative conversion rate in NC groups was higher than that of LC groups (RD=0.03; 95% CI, 0.01-0.06; P=0.02). Conclusions: There is no significate difference between the safety of NC and laparoscope cholecystectomy. NC is associated with a higher rate of intraoperative conversion when compared with LC. It is worthy of further promotion and validation in clinical settings. PMID:27557339

Improvement of ethanol yield from glycerol via conversion of pyruvate to ethanol in metabolically engineered Saccharomyces cerevisiae.

PubMed

Yu, Kyung Ok; Jung, Ju; Ramzi, Ahmad Bazli; Kim, Seung Wook; Park, Chulhwan; Han, Sung Ok

2012-02-01

The conversion of low-priced glycerol to higher value products has been proposed as a way to improve the economic viability of the biofuels industry. In a previous study, the conversion of glycerol to ethanol in a metabolically engineered strain of Saccharomyces cerevisiae was accomplished by minimizing the synthesis of glycerol, the main by-product in ethanol fermentation processing. To further improve ethanol production, overexpression of the native genes involved in conversion of pyruvate to ethanol in S. cerevisiae was successfully accomplished. The overexpression of an alcohol dehydrogenase (adh1) and a pyruvate decarboxylase (pdc1) caused an increase in growth rate and glycerol consumption under fermentative conditions, which led to a slight increase of the final ethanol yield. The overall expression of the adh1 and pdc1 genes in the modified strains, combined with the lack of the fps1 and gpd2 genes, resulted in a 1.4-fold increase (about 5.4 g/L ethanol produced) in fps1Δgpd2Δ (pGcyaDak, pGupCas) (about 4.0 g/L ethanol produced). In summary, it is possible to improve the ethanol yield by overexpression of the genes involved in the conversion of pyruvate to ethanol in engineered S. cerevisiae using glycerol as substrate.

Short-term consequences of slash-and-burn practices on the arbuscular mycorrhizal fungi of a tropical dry forest.

PubMed

Aguilar-Fernández, Mónica; Jaramillo, Víctor J; Varela-Fregoso, Lucía; Gavito, Mayra E

2009-03-01

Rates of land conversion from forest to cultivated land by slash-and-burn practices are higher in tropical dry forest (TDF) than any other Neotropical forest type. This study examined the short-term consequences of the slash-and-burn process on arbuscular mycorrhizal fungi (AMF). We expected that slash-and-burn would reduce mycorrhizal colonization and propagules and change species richness and composition. Soil and root samples were taken from TDF control and pasture plots originated after slash-and-burn at four dates during the year of conversion to examine species composition, spore abundance, and infective propagules. Additionally, spore abundance and viability and viable intraradical colonization were measured twice during the second year after conversion. Forest and pasture plots maintained similar species richness and an overall 84% similarity during the first year after conversion. Infective propagules were reduced in pasture plots during the first year after slash-and-burn, whereas spore abundance and intraradical colonization remained similar in TDF and pasture plots both years of the study. Our results suggest, contrary to the expected, that forest conversion by means of slash-and-burn followed by cultivation resulted in few immediate changes in the AMF communities, likely because of the low heat conductivity of the soil and rapid combustion of plant residues.

Multiphysics Computational Analysis of a Solid-Core Nuclear Thermal Engine Thrust Chamber

NASA Technical Reports Server (NTRS)

Wang, Ten-See; Canabal, Francisco; Cheng, Gary; Chen, Yen-Sen

2007-01-01

The objective of this effort is to develop an efficient and accurate computational heat transfer methodology to predict thermal, fluid, and hydrogen environments for a hypothetical solid-core, nuclear thermal engine - the Small Engine. In addition, the effects of power profile and hydrogen conversion on heat transfer efficiency and thrust performance were also investigated. The computational methodology is based on an unstructured-grid, pressure-based, all speeds, chemically reacting, computational fluid dynamics platform, while formulations of conjugate heat transfer were implemented to describe the heat transfer from solid to hydrogen inside the solid-core reactor. The computational domain covers the entire thrust chamber so that the afore-mentioned heat transfer effects impact the thrust performance directly. The result shows that the computed core-exit gas temperature, specific impulse, and core pressure drop agree well with those of design data for the Small Engine. Finite-rate chemistry is very important in predicting the proper energy balance as naturally occurring hydrogen decomposition is endothermic. Locally strong hydrogen conversion associated with centralized power profile gives poor heat transfer efficiency and lower thrust performance. On the other hand, uniform hydrogen conversion associated with a more uniform radial power profile achieves higher heat transfer efficiency, and higher thrust performance.

Quantifying above- and belowground biomass carbon loss with forest conversion in tropical lowlands of Sumatra (Indonesia).

PubMed

Kotowska, Martyna M; Leuschner, Christoph; Triadiati, Triadiati; Meriem, Selis; Hertel, Dietrich

2015-10-01

Natural forests in South-East Asia have been extensively converted into other land-use systems in the past decades and still show high deforestation rates. Historically, lowland forests have been converted into rubber forests, but more recently, the dominant conversion is into oil palm plantations. While it is expected that the large-scale conversion has strong effects on the carbon cycle, detailed studies quantifying carbon pools and total net primary production (NPPtotal ) in above- and belowground tree biomass in land-use systems replacing rainforest (incl. oil palm plantations) are rare so far. We measured above- and belowground carbon pools in tree biomass together with NPPtotal in natural old-growth forests, 'jungle rubber' agroforests under natural tree cover, and rubber and oil palm monocultures in Sumatra. In total, 32 stands (eight plot replicates per land-use system) were studied in two different regions. Total tree biomass in the natural forest (mean: 384 Mg ha(-1) ) was more than two times higher than in jungle rubber stands (147 Mg ha(-1) ) and >four times higher than in monoculture rubber and oil palm plantations (78 and 50 Mg ha(-1) ). NPPtotal was higher in the natural forest (24 Mg ha(-1)  yr(-1) ) than in the rubber systems (20 and 15 Mg ha(-1)  yr(-1) ), but was highest in the oil palm system (33 Mg ha(-1)  yr(-1) ) due to very high fruit production (15-20 Mg ha(-1)  yr(-1) ). NPPtotal was dominated in all systems by aboveground production, but belowground productivity was significantly higher in the natural forest and jungle rubber than in plantations. We conclude that conversion of natural lowland forest into different agricultural systems leads to a strong reduction not only in the biomass carbon pool (up to 166 Mg C ha(-1) ) but also in carbon sequestration as carbon residence time (i.e. biomass-C:NPP-C) was 3-10 times higher in the natural forest than in rubber and oil palm plantations. © 2015 John Wiley & Sons Ltd.

The influence of atmospheric turbulence on partially coherent two-photon entangled field

NASA Astrophysics Data System (ADS)

Qiu, Y.; She, W.

2012-09-01

The propagation of a two-photon field from down-conversion of a partially coherent Gaussian Schell-model (GSM) pump beam in free space has been reported. However, the propagation of this two-photon field through a turbulent atmosphere has not been investigated yet. In this paper, an analytical expression of the coincidence count rate of the two-photon entangled field is derived. Unlike what has been reported, the field is from a parameter down-conversion of a partially coherent dark hollow pump beam and propagates through a turbulent atmosphere. The effects of the propagation parameters on the coincidence count rate are evaluated and illustrated. The results show that the pump beam parameters and atmospheric turbulence can evidently affect the detection probability of the photon pair at two different positions. It is found that the detection probability of the two-photon field is higher, and thus less susceptible to turbulence, if the field is produced by a lower mode of partially coherent pump beam.

The effect of nonenzymatic protein on lignocellulose enzymatic hydrolysis and simultaneous saccharification and fermentation.

PubMed

Wang, Hui; Kobayashi, Shinichi; Hiraide, Hatsue; Cui, Zongjun; Mochidzuki, Kazuhiro

2015-01-01

Nonenzymatic protein was added to cellulase hydrolysis and simultaneous saccharification and fermentation (SSF) of different biomass materials. Adding bovine serum albumin (BSA) and corn steep before cellulase enhanced enzyme activity in solution and increased cellulose and xylose conversion rates. The cellulose conversion rate of filter paper hydrolysis was increased by 32.5 % with BSA treatment. When BSA was added before cellulase, the remaining activity in the solution was higher than that in a control without BSA pretreatment. During SSF with pretreated rice straw as the substrate, adding 1.0 mg/mL BSA increased the ethanol yield by 13.6 % and final xylose yield by 42.6 %. The results indicated that lignin interaction is not the only mechanism responsible for the positive BSA effect. BSA had a stabilizing effect on cellulase and relieved cumulative sugar inhibition of enzymatic hydrolysis of biomass materials. Thus, nonenzymatic protein addition represents a promising strategy in the biorefining of lignocellulose materials.

Physicochemical pretreatments and hydrolysis of furfural residues via carbon-based sulfonated solid acid.

PubMed

Ma, Bao Jun; Sun, Yuan; Lin, Ke Ying; Li, Bing; Liu, Wan Yi

2014-03-01

Potential commercial physicochemical pretreatment methods, NaOH/microwave and NaOH/ultrasound were developed, and the carbon-based sulfonated solid acid catalysts were prepared for furfural residues conversion into reducing sugars. After the two optimum pretreatments, both the content of cellulose increased (74.03%, 72.28%, respectively) and the content of hemicellulose (94.11%, 94.17% of removal rate, respectively) and lignin (91.75%, 92.09% of removal rate, respectively) decreased in furfural residues. The reducing sugar yields of furfural residues with the two physicochemical pretreatments on coal tar-based solid acid reached 33.94% and 33.13%, respectively, higher than that pretreated via NaOH alone (27%) and comparable to that pretreated via NaOH/H2O2 (35.67%). The XRD patterns, IR spectra and SEM images show microwave and ultrasound improve the pretreatment effect. The results demonstrate the carbon-based sulfonated solid acids and the physicochemical pretreatments are green, effective, low-cost for furfural residues conversion. Copyright © 2014 Elsevier Ltd. All rights reserved.

Thermoliquefaction of palm oil fiber (Elaeis sp.) using supercritical ethanol.

PubMed

Oliveira, Aline L P C; Almeida, Priscila S; Campos, Maria C V; Franceschi, Elton; Dariva, Cláudio; Borges, Gustavo R

2017-04-01

Thermoliquefaction of palm oil fiber was investigated using supercritical ethanol as solvent. A semi-continuous laboratory scale unit was developed to investigate the effects of temperature (300-500°C), heating rate (10-30°C.min -1 ) and cracking time (10-30min) on the conversion of biomass in bio-oil. The main advantage of the proposed process is that a pure solvent is pumping through the reactor that contains the biomass, dispensing the use of biomass slurries. The yield of bio-oil ranged from 56% to 84%, depending on the experimental conditions. It was observed that an increase in working temperature led to an increase in the bio-oil production. Cracking time and heating rate variation had not shown a considerable effect on the conversion of biomass. The chemical profiles of bio-oil determined by GC/MS, indicate that at low temperature mainly sugar derivatives are produced, while at higher temperatures alcohols and phenolic are the majority compounds of the bio-oil. Copyright © 2017 Elsevier Ltd. All rights reserved.

Reactivity study on thermal cracking of vacuum residues

NASA Astrophysics Data System (ADS)

León, A. Y.; Díaz, S. D.; Rodríguez, R. C.; Laverde, D.

2016-02-01

This study focused on the process reactivity of thermal cracking of vacuum residues from crude oils mixtures. The thermal cracking experiments were carried out under a nitrogen atmosphere at 120psi between 430 to 500°C for 20 minutes. Temperature conditions were established considering the maximum fractional conversion reported in tests of thermogravimetry performed in the temperature range of 25 to 600°C, with a constant heating rate of 5°C/min and a nitrogen flow rate of 50ml/min. The obtained products were separated in to gases, distillates and coke. The results indicate that the behaviour of thermal reactivity over the chemical composition is most prominent for the vacuum residues with higher content of asphaltenes, aromatics, and resins. Finally some correlations were obtained in order to predict the weight percentage of products from its physical and chemical properties such as CCR, SARA (saturates, aromatics, resins, asphaltenes) and density. The results provide new knowledge of the effect of temperature and the properties of vacuum residues in thermal conversion processes.

Conversion of Society for Maternal-Fetal Medicine abstract presentations to manuscript publications.

PubMed

Manuck, Tracy A; Barbour, Kelli; Janicki, Lindsay; Blackwell, Sean C; Berghella, Vincenzo

2015-09-01

We sought to evaluate the rate of conversion of Society for Maternal-Fetal Medicine (SMFM) annual meeting abstract presentations to full manuscript publications over time. Full manuscript publications corresponding to all SMFM oral abstracts 2003 through 2010 inclusive, and SMFM poster abstracts in 2003, 2005, 2007, and 2009 were manually searched in PubMed. An abstract was considered to "match" a full publication if the abstract and publication titles as well as main methods and results were similar and the abstract first author was a publication author. In cases of uncertainty, the abstract-publication match was reviewed by a second physician researcher. Time to publication, publication rates over time, and publication rates among US vs non-US authors were examined. PubMed identification numbers were also collected to determine if >1 abstract contributed to a manuscript. Data were analyzed using Wilcoxon rank sum, analysis of variance, t test, and logistic regression. In all, 3281 abstracts presented at SMFM over the study period, including 629 orals (63 main plenary, 64 fellows plenary, 502 concurrent), were reviewed. Of 3281, 1780 (54.3%) were published, generating 1582 unique publications. Oral abstracts had a consistently higher rate of conversion to publications vs posters (77.1% vs 48.8%, P < .001). The median time to publication was 19 (interquartile range, 9-36) months, and was significantly shorter for orals vs posters (11 vs 21 months, P < .001). Over the study period, rates of publication of orals remained constant, but rates of publication of posters were lower in 2007 and 2009 compared to 2003 and 2005. Publications related to SMFM abstracts were published in 194 different journals, most commonly American Journal of Obstetrics and Gynecology (39.8%), Obstetrics and Gynecology (9.7%), and Journal of Maternal-Fetal and Neonatal Medicine (6.5%). Publication rates were higher if the abstract's first author was affiliated with a non-US institution (64.8% vs 51.1%, P < .001) and if the abstract received an award (82.7% vs 53.3%, P < .001). In regression models, oral presentation at SMFM, first author affiliation with a non-US institution, submission for American Journal of Obstetrics and Gynecology SMFM special issue, and year of abstract presentation at SMFM were associated with full manuscript publication. From 2003 through 2010, full manuscript publication rates of SMFM abstracts were high and consistent, and time to publication decreased/improved across the study period for oral presentations. Copyright © 2015 Elsevier Inc. All rights reserved.

Effects of rearing density and raceway conformation on growth, food conversion, and survival of juvenile spring chinook salmon

USGS Publications Warehouse

Ewing, R.D.; Sheahan, J.E.; Lewis, M.A.; Palmisano, Aldo N.

2000-01-01

Four brood years of juvenile spring chinook salmon Oncorhynchus tshawytscha were reared in conventional and baffled raceways at various rearing densities and loads at Willamette Hatchery, Oregon. A period of rapid linear growth occurred from August to November, but there was little or no growth from November to March when the fish were released. Both fall and winter growth rates were inversely related to rearing density. Final weight and length were also inversely related to rearing density. No significant relationship between load and any growth variable was observed. Fish reared at lower densities in conventional raceways tended to develop bimodal length distributions in winter and early spring. Fish reared in conventional raceways showed significantly larger growth rates and final lengths and weights than those reared in baffled raceways. Food conversions and average delivery times for feed were significantly greater in baffled than in conventional raceways. No significant relationships were observed between either rearing density or load and condition factor, food conversion, or mortality. Mortality was not significantly different between the two raceway types. When fish were transported to seawater for further rearing, there were no significant relationships between mortality in seawater and rearing density or load, but fish reared in baffled raceways had significantly higher mortality than those reared in conventional raceways.

Recent rates of forest harvest and conversion in North America

Treesearch

Jeffrey G. Masek; Warren B. Cohen; Donald Leckie; Michael A. Wulder; Rodrigo Vargas; Ben de Jong; Sean Healey; Beverly Law; Richard Birdsey; R. A. Houghton; David Mildrexler; Samuel Goward; W. Brad Smith

2011-01-01

Incorporating ecological disturbance into biogeochemical models is critical for estimating current and future carbon stocks and fluxes. In particular, anthropogenic disturbances, such as forest conversion and wood harvest, strongly affect forest carbon dynamics within North America. This paper summarizes recent (2000-2008) rates of extraction, including both conversion...

Method and apparatus for optical encoding with compressible imaging

NASA Technical Reports Server (NTRS)

Leviton, Douglas B. (Inventor)

2006-01-01

The present invention presents an optical encoder with increased conversion rates. Improvement in the conversion rate is a result of combining changes in the pattern recognition encoder's scale pattern with an image sensor readout technique which takes full advantage of those changes, and lends itself to operation by modern, high-speed, ultra-compact microprocessors and digital signal processors (DSP) or field programmable gate array (FPGA) logic elements which can process encoder scale images at the highest speeds. Through these improvements, all three components of conversion time (reciprocal conversion rate)--namely exposure time, image readout time, and image processing time--are minimized.

Converting positive and negative symptom scores between PANSS and SAPS/SANS.

PubMed

van Erp, Theo G M; Preda, Adrian; Nguyen, Dana; Faziola, Lawrence; Turner, Jessica; Bustillo, Juan; Belger, Aysenil; Lim, Kelvin O; McEwen, Sarah; Voyvodic, James; Mathalon, Daniel H; Ford, Judith; Potkin, Steven G; Fbirn

2014-01-01

The Scale for the Assessment of Positive Symptoms (SAPS), the Scale for the Assessment of Negative Symptoms (SANS), and the Positive and Negative Syndrome Scale for Schizophrenia (PANSS) are the most widely used schizophrenia symptom rating scales, but despite their co-existence for 25 years no easily usable between-scale conversion mechanism exists. The aim of this study was to provide equations for between-scale symptom rating conversions. Two-hundred-and-five schizophrenia patients [mean age±SD=39.5±11.6, 156 males] were assessed with the SANS, SAPS, and PANSS. Pearson's correlations between symptom scores from each of the scales were computed. Linear regression analyses, on data from 176 randomly selected patients, were performed to derive equations for converting ratings between the scales. Intraclass correlations, on data from the remaining 29 patients, not part of the regression analyses, were performed to determine rating conversion accuracy. Between-scale positive and negative symptom ratings were highly correlated. Intraclass correlations between the original positive and negative symptom ratings and those obtained via conversion of alternative ratings using the conversion equations were moderate to high (ICCs=0.65 to 0.91). Regression-based equations may be useful for conversion between schizophrenia symptom severity as measured by the SANS/SAPS and PANSS, though additional validation is warranted. This study's conversion equations, implemented at http:/converteasy.org, may aid in the comparison of medication efficacy studies, in meta- and mega-analyses examining symptoms as moderator variables, and in retrospective combination of symptom data in multi-center data sharing projects that need to pool symptom rating data when such data are obtained using different scales. Copyright © 2013 Elsevier B.V. All rights reserved.

Efficient electrochemical CO2 conversion powered by renewable energy.

PubMed

Kauffman, Douglas R; Thakkar, Jay; Siva, Rajan; Matranga, Christopher; Ohodnicki, Paul R; Zeng, Chenjie; Jin, Rongchao

2015-07-22

The catalytic conversion of CO2 into industrially relevant chemicals is one strategy for mitigating greenhouse gas emissions. Along these lines, electrochemical CO2 conversion technologies are attractive because they can operate with high reaction rates at ambient conditions. However, electrochemical systems require electricity, and CO2 conversion processes must integrate with carbon-free, renewable-energy sources to be viable on larger scales. We utilize Au25 nanoclusters as renewably powered CO2 conversion electrocatalysts with CO2 → CO reaction rates between 400 and 800 L of CO2 per gram of catalytic metal per hour and product selectivities between 80 and 95%. These performance metrics correspond to conversion rates approaching 0.8-1.6 kg of CO2 per gram of catalytic metal per hour. We also present data showing CO2 conversion rates and product selectivity strongly depend on catalyst loading. Optimized systems demonstrate stable operation and reaction turnover numbers (TONs) approaching 6 × 10(6) molCO2 molcatalyst(-1) during a multiday (36 h total hours) CO2 electrolysis experiment containing multiple start/stop cycles. TONs between 1 × 10(6) and 4 × 10(6) molCO2 molcatalyst(-1) were obtained when our system was powered by consumer-grade renewable-energy sources. Daytime photovoltaic-powered CO2 conversion was demonstrated for 12 h and we mimicked low-light or nighttime operation for 24 h with a solar-rechargeable battery. This proof-of-principle study provides some of the initial performance data necessary for assessing the scalability and technical viability of electrochemical CO2 conversion technologies. Specifically, we show the following: (1) all electrochemical CO2 conversion systems will produce a net increase in CO2 emissions if they do not integrate with renewable-energy sources, (2) catalyst loading vs activity trends can be used to tune process rates and product distributions, and (3) state-of-the-art renewable-energy technologies are sufficient to power larger-scale, tonne per day CO2 conversion systems.

Site-specific lead exposure from lead pellet ingestion in sentinel mallards

USGS Publications Warehouse

Rocke, T.E.; Brand, C.J.; Mensik, John G.

1997-01-01

We monitored lead poisoning from the ingestion of spent lead pellets in sentinel mallards (Anas platyhrynchos) at the Sacramento National Wildlife Refuge (SNWR), Willows, California for 4 years (1986-89) after the conversion to steel shot for waterfowl hunting on refuges in 1986. Sentinel mallards were held in 1.6-ha enclosures in 1 hunted (P8) and 2 non-hunted (T19 and TF) wetlands. We compared site-specific rates of lead exposure, as determined by periodic measurement of blood lead concentrations, and lead poisoning mortality between wetlands with different lead pellet densities, between seasons, and between male and female sentinels. In 1986, the estimated 2-week rate of lead exposure was significantly higher (P < 0.005) in P8 (43.8%), the wetland with the highest density of spent lead pellets (>2,000,000 pellets/ha), than in those with lower densities of lead pellets, T19 (18.1%; 173,200 pellets/ha) and TF (0.9%; 15,750 pellets/ha). The probability of mortality from lead poisoning was also significantly higher (P < 0.01) in sentinel mallards enclosed in P8 (0.25) than T19 (0) and TF (0) in 1986 and remained significantly higher (P < 0.001) during the 4-year study. Both lead exposure and the probability of lead poisoning mortality in P8 were significantly higher (P < 0.001) in the fall of 1986 (43.8%; 0.25), before hunting season, than in the spring of 1987 (21.6%; 0.04), after hunting season. We found no significant differences in the rates of lead exposure or lead poisoning mortality between male and female sentinel mallards. The results of this study demonstrate that in some locations, lead exposure and lead poisoning in waterfowl will continue to occur despite the conversion to steel shot for waterfowl hunting.

Physiological Reactivity During Parent-Adolescent Discussions: Associations with Scaffolding Behaviors and Relationship Quality.

PubMed

Manczak, Erika M; McLean, Kate C; McAdams, Dan P; Chen, Edith

2015-08-01

Parents and adolescents commonly discuss stressful experiences. However, little is known about the features of these conversations that may have implications for health. One hundred five adolescents and their parents engaged in conversations about two challenging events, with parental contributions to the discussions coded for four scaffolding behaviors (reiterations, negations, move alongs, and new interpretations). Systolic blood pressure, diastolic blood pressure, and heart rate were measured in both participants at baseline and throughout the conversation. Parent-reported relationship quality was also assessed. For both parents and adolescents, negative scaffolding behaviors were associated with increased physiological reactivity, whereas positive scaffolding behaviors were associated with decreased reactivity. Furthermore, children in higher quality parent-child relationships showed greater reactivity to reiterations and lower reactivity to new interpretations, but those in lower quality relationships demonstrated the opposite patterns. Specific aspects of parent-child interactions appear to contribute to physiological responses to challenging events, which in turn may have implications for health.

Chlorination of alumina in kaolinitic clay

NASA Astrophysics Data System (ADS)

Grob, B.; Richarz, W.

1984-09-01

The chlorination of alumina in kaolinitic clay with Cl2 and CO gas mixtures was studied gravimetrically. The effects of the calcination method and of NaCl addition on the reactivity of the clay were examined. Fast reaction rates were achieved only with samples previously exposed to a sulfating treatment. Optimum conditions, with maximum yield and selectivity to A1C13 and minimum SiO2 conversion, were found between 770 and 970 K. At higher temperatures the SiCl4 formed poisons the reactive alumina surface by selective chemisorption with a marked decrease of the reaction rate.

Quantifying Blood Loss and Transfusion Risk After Primary vs Conversion Total Hip Arthroplasty.

PubMed

Newman, Jared M; Webb, Matthew R; Klika, Alison K; Murray, Trevor G; Barsoum, Wael K; Higuera, Carlos A

2017-06-01

Primary total hip arthroplasty (THA) and conversion THA may result in substantial blood loss, sometimes necessitating transfusion. Despite the complexities of the latter, both are grouped in the same category for quality assessment and reimbursement. This study's purpose was to compare both blood loss and transfusion risk in primary and conversion THA and identify their associated predictors. A total of 1616 patients who underwent primary and conversion THA at a single hospital from 2009-2013 were reviewed (primary THA = 1575; conversion THA = 41). Demographics, comorbidities, and perioperative data were collected from electronic records. Blood loss was calculated using a validated method. Transfusion triggers were based on standardized criteria. Separate multivariable regression models for blood loss and transfusion were performed. Conversion THA patients were younger (P = .002), had lower age-adjusted Charlson scores (P = .006), longer surgeries (P < .001), higher blood loss (P < .001), and more transfusions (P < .001). Primary and conversion THA groups were different in terms of surgical approach (P < .001), anesthesia type (P = .002), and venous thromboembolism prophylaxis (P = .01). Compared to primary THA, conversion THA had an average 478.9 mL higher blood loss (P = .003) and increased adjusted odds ratio of 3.2 (P = .019) for transfusion. Conversion THA leads to higher blood loss and transfusion compared with primary THA. These differences were quantified in the present study and showed consistent results between the 2 metrics. The differences between these procedures should be addressed during quality assurance because conversion THA is associated with higher resource utilization, which is important in the allocation of resources and tiered reimbursement strategies. Copyright © 2017 Elsevier Inc. All rights reserved.

[Analysis and publication rate of the presentations at the Turkish National Otorhinolaryngology and Head and Neck Surgery meetings].

PubMed

Erdağ, Taner Kemal; Durmuşoğlu, Mehmet; Demir, Ali Oğuz; Doğan, Ersoy; Ikiz, Ahmet Omer

2014-01-01

This study aims to evaluate the analysis and publication rates of presentations presented at the Turkish National Otorhinolaryngology and Head & Neck Surgery (TNORL and HNS) meetings. The TNORL and HNS meetings of 2008, 2009 and 2010 were included in the study. The number, subjects, types (clinical study, experimental study, case report) and institutions of the oral presentations and posters were documented using the abstract CD's of the meetings. The conversion rate of presentations into the full-text articles in the peer-reviewed journals were reviewed through the search engines Pubmed for the international indexes and Türk Medline and Ulakbim for the national ones. The time from presentation in the meetings to publication was determined. The distribution of journals according to the publication dates of the articles were evaluated in terms of the Science citation index (SCI), SCI expanded (SCI-E), PubMed and Turkish citation index. The total number of presentations submitted in the three TNORL and HNS meetings was 1,454 and posters accounted for 75.4% of all presentations. While case reports were 53.2% of the total presentations, the ratios were found to be 43% and 3.8% for the research and experimental studies, respectively. Of the oral presentations, 88% included research studies, whereas 70.3% of the posters were case reports. The origin of the presentations was university hospitals, education hospitals, other national institutions, and international institutions with ratios of 51.6%, 44.3%, 3% and 1.1%, respectively. The conversion rate of presentations into the full-text articles was found as 21.9%. The rate was 37.3% for oral presentations and 17% for the posters (p=0.00). For all of the 319 published papers, the overall mean time from presentation to publication was 18.6 months. While 62.7% of the articles were published in international journals, 37.3% were published in national journals. The conversion rate of oral presentations into publications was higher than the posters (p=0.00). The first study related to TNORL and HNS meetings in Turkey revealed that, although the quantity of presentations was high, the rate of conversion into the full-text journal articles was lower compared to the similar international annual meetings held by otorhinolaryngology or other disciplines. The quality and success of our scientific meetings can be enhanced with some particular precautions.

A retrospective comparison of robotic cholecystectomy versus laparoscopic cholecystectomy: operative outcomes and cost analysis.

PubMed

Strosberg, David S; Nguyen, Michelle C; Muscarella, Peter; Narula, Vimal K

2017-03-01

Robotic-assisted surgery is gaining popularity in general surgery. Our objective was to evaluate and compare operative outcomes and total costs for robotic cholecystectomy (RC) and laparoscopic cholecystectomy (LC). A retrospective review was performed for all patients who underwent single-procedure RC and LC from January 2011 to July 2015 by a single surgeon at a large academic medical center. Demographics, diagnosis, perioperative variables, postoperative complications, 30-day readmissions, and operative and hospital costs were collected and analyzed between those patient groups. A total of 237 patients underwent RC or LC, and comprised the study population. Ninety-seven patients (40.9 %) underwent LC, and 140 patients (50.1 %) underwent RC. Patients who underwent RC had a higher body mass index (p = 0.03), lower rates of coronary artery disease (p < 0.01), and higher rates of chronic cholecystitis (p < 0.01). There were lower rates of intraoperative cholangiography (p < 0.01) and conversion to an open procedure (p < 0.01), however longer operative times (p < 0.01) for patients in the RC group. There were no bile duct injuries in either group, no difference in bile leak rates (p = 0.65), or need for reoperation (p = 1.000). Cost analysis of outpatient-only procedures, excluding cases with conversion to open or use of intraoperative cholangiography, demonstrated higher total charges (p < 0.01) and cost (p < 0.01) and lower revenue (p < 0.01) for RC compared to LC, with no difference in total payments (p = 0.34). Robotic cholecystectomy appears to be safe although costlier in comparison with laparoscopic cholecystectomy. Further studies are needed to understand the long-term implications of robotic technology, the cost to the health care system, and its role in minimally invasive surgery.

Property evolution during vitrification of dimethacrylate photopolymer networks

PubMed Central

Abu-Elenain, Dalia; Lewis, Steven H.; Stansbury, Jeffrey W.

2013-01-01

Objectives This study seeks to correlate the interrelated properties of conversion, shrinkage, modulus and stress as dimethacrylate networks transition from rubbery to glassy states during photopolymerization. Methods An unfilled BisGMA/TEGDMA resin was photocured for various irradiation intervals (7–600 s) to provide controlled levels of immediate conversion, which was monitored continuously for 10 min. Fiber optic near-infrared spectroscopy permitted coupling of real-time conversion measurement with dynamic polymerization shrinkage (linometer), modulus (dynamic mechanical analyzer) and stress (tensometer) development profiles. Results The varied irradiation conditions produced final conversion ranging from 6 % to more than 60 %. Post-irradiation conversion (dark cure) was quite limited when photopolymerization was interrupted either at very low or very high levels of conversion while significant dark cure contributions were possible for photocuring reactions suspended within the post-gel, rubbery regime. Analysis of conversion-based property evolution during and subsequent to photocuring demonstrated that the shrinkage rate increased significantly at about 40 % conversion followed by late-stage suppression in the conversion-dependent shrinkage rate that begins at about 45–50 % conversion. The gradual vitrification process over this conversion range is evident based on the broad but well-defined inflection in the modulus versus conversion data. As limiting conversion is approached, modulus and, to a somewhat lesser extent, stress rise precipitously as a result of vitrification with the stress profile showing little if any late-stage suppression as seen with shrinkage. Significance Near the limiting conversion for this model resin, the volumetric polymerization shrinkage rate slows while an exponential rise in modulus promotes the vitrification process that appears to largely dictate stress development. PMID:24080378

Quality by Design approach to spray drying processing of crystalline nanosuspensions.

PubMed

Kumar, Sumit; Gokhale, Rajeev; Burgess, Diane J

2014-04-10

Quality by Design (QbD) principles were explored to understand spray drying process for the conversion of liquid nanosuspensions into solid nano-crystalline dry powders using indomethacin as a model drug. The effects of critical process variables: inlet temperature, flow and aspiration rates on critical quality attributes (CQAs): particle size, moisture content, percent yield and crystallinity were investigated employing a full factorial design. A central cubic design was employed to generate the response surface for particle size and percent yield. Multiple linear regression analysis and ANOVA were employed to identify and estimate the effect of critical parameters, establish their relationship with CQAs, create design space and model the spray drying process. Inlet temperature was identified as the only significant factor (p value <0.05) to affect dry powder particle size. Higher inlet temperatures caused drug surface melting and hence aggregation of the dried nano-crystalline powders. Aspiration and flow rates were identified as significant factors affecting yield (p value <0.05). Higher yields were obtained at higher aspiration and lower flow rates. All formulations had less than 3% (w/w) moisture content. Formulations dried at higher inlet temperatures had lower moisture compared to those dried at lower inlet temperatures. Published by Elsevier B.V.

Modeling and simulation of an enzymatic reactor for hydrolysis of palm oil.

PubMed

Bhatia, S; Naidu, A D; Kamaruddin, A H

1999-01-01

Hydrolysis of palm oil has become an important process in Oleochemical industries. Therefore, an investigation was carried out for hydrolysis of palm oil to fatty acid and glycerol using immobilized lipase in packed bed reactor. The conversion vs. residence time data were used in Michaelis-Menten rate equation to evaluate the kinetic parameters. A mathematical model for the rate of palm oil hydrolysis was proposed incorporating role of external mass transfer and pore diffusion. The model was simulated for steady-state isothermal operation of immobilized lipase packed bed reactor. The experimental data were compared with the simulated results. External mass transfer was found to affect the rate of palm oil hydrolysis at higher residence time.

Studies on biomass char gasification and dynamics

NASA Astrophysics Data System (ADS)

You, Zhanping; You, Shijun; Ma, Xiaoyan

2018-01-01

The gasification performances of two kinds of biomass char by experiment methods are studied, including conversion rate and gasification gas component with temperature and time. Experimental results show that gasification temperature has important effects on the conversion rate and gas component. In the range of experimental temperature, char conversion rates are no more than 30.0%. The apparent activation energies and apparent reaction frequency factors of two biomass chars are obtained through kinetic studies.

Accelerated Growth Rate Induced by Neonatal High-Protein Milk Formula Is Not Supported by Increased Tissue Protein Synthesis in Low-Birth-Weight Piglets

PubMed Central

Jamin, Agnès; Sève, Bernard; Thibault, Jean-Noël; Floc'h, Nathalie

2012-01-01

Low-birth-weight neonates are routinely fed a high-protein formula to promote catch-up growth and antibiotics are usually associated to prevent infection. Yet the effects of such practices on tissue protein metabolism are unknown. Baby pigs were fed from age 2 to 7 or 28 d with high protein formula with or without amoxicillin supplementation, in parallel with normal protein formula, to determine tissue protein metabolism modifications. Feeding high protein formula increased growth rate between 2 and 28 days of age when antibiotic was administered early in the first week of life. This could be explained by the occurrence of diarrhea when piglets were fed the high protein formula alone. Higher growth rate was associated with higher feed conversion and reduced protein synthesis rate in the small intestine, muscle and carcass, whereas proteolytic enzyme activities measured in these tissues were unchanged. In conclusion, accelerated growth rate caused by high protein formula and antibiotics was not supported by increased protein synthesis in muscle and carcass. PMID:22315674

Health communication cards as a tool for behaviour change.

PubMed

Matteson, Carrie L; Merth, Thomas D N; Finegood, Diane T

2014-01-01

Individuals seeking healthcare treatment in the context of obesity often experience difficulty engaging in discussions around their health and face challenges finding consensus with practitioners on care plans that best suit their lives. The complex set of biological, social, and environmental variables that have contributed to the higher prevalence of obesity are well illustrated in the foresight obesity system map. Effectively understanding and addressing key variables for each individual has proven to be difficult, with clinicians facing barriers and limited resources to help address patients' unique needs. However, productive discussions inspired by patient centered care may be particularly effective in promoting behaviour change. Tools based on systems science that facilitate patient centered care and help identify behaviour change priorities have not been developed to help treat adult obesity. This project created and pilot tested a card based clinical communication tool designed to help facilitate conversations with individuals engaged in health behaviour change. The health communication cards were designed to help direct conversation between patients and healthcare providers toward issues relevant to the individual. Use of the cards to facilitate patient driven conversations in clinical care may help to streamline conversations, set realistic care plan goals, and improve long term rates of compliance.

Electrochemically enhanced microbial CO conversion to volatile fatty acids using neutral red as an electron mediator.

PubMed

Im, Chae Ho; Kim, Changman; Song, Young Eun; Oh, Sang-Eun; Jeon, Byong-Hun; Kim, Jung Rae

2018-01-01

Conversion of C1 gas feedstock, including carbon monoxide (CO), into useful platform chemicals has attracted considerable interest in industrial biotechnology. Nevertheless, the low conversion yield and/or growth rate of CO-utilizing microbes make it difficult to develop a C1 gas biorefinery process. The Wood-Ljungdahl pathway which utilize CO is a pathway suffered from insufficient electron supply, in which the conversion can be increased further when an additional electron source like carbohydrate or hydrogen is provided. In this study, electrode-based electron transference using a bioelectrochemical system (BES) was examined to compensate for the insufficient reducing equivalent and increase the production of volatile fatty acids. The BES including neutral red (BES-NR), which facilitated electron transfer between bacteria and electrode, was compared with BES without neutral red and open circuit control. The coulombic efficiency based on the current input to the system and the electrons recovered into VFAs, was significantly higher in BES-NR than the control. These results suggest that the carbon electrode provides a platform to regulate the redox balance for improving the bioconversion of CO, and amending the conventional C1 gas fermentation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of land use change on soil gross nitrogen transformation rates in subtropical acid soils of Southwest China.

PubMed

Xu, Yongbo; Xu, Zhihong

2015-07-01

Land use change affects soil gross nitrogen (N) transformations, but such information is particularly lacking under subtropical conditions. A study was carried out to investigate the potential gross N transformation rates in forest and agricultural (converted from the forest) soils in subtropical China. The simultaneously occurring gross N transformations in soil were quantified by a (15)N tracing study under aerobic conditions. The results showed that change of land use types substantially altered most gross N transformation rates. The gross ammonification and nitrification rates were significantly higher in the agricultural soils than in the forest soils, while the reverse was true for the gross N immobilization rates. The higher total carbon (C) concentrations and C / N ratio in the forest soils relative to the agricultural soils were related to the greater gross N immobilization rates in the forest soils. The lower gross ammonification combined with negligible gross nitrification rates, but much higher gross N immobilization rates in the forest soils than in the agricultural soils suggest that this may be a mechanism to effectively conserve available mineral N in the forest soils through increasing microbial biomass N, the relatively labile organic N. The greater gross nitrification rates and lower gross N immobilization rates in the agricultural soils suggest that conversion of forests to agricultural soils may exert more negative effects on the environment by N loss through NO3 (-) leaching or denitrification (when conditions for denitrification exist).

Serious Illness Conversations in ESRD

PubMed Central

Bernacki, Rachelle E.; Block, Susan D.

2017-01-01

Dialysis-dependent ESRD is a serious illness with high disease burden, morbidity, and mortality. Mortality in the first year on dialysis for individuals over age 75 years old approaches 40%, and even those with better prognoses face multiple hospitalizations and declining functional status. In the last month of life, patients on dialysis over age 65 years old experience higher rates of hospitalization, intensive care unit admission, procedures, and death in hospital than patients with cancer or heart failure, while using hospice services less. This high intensity of care is often inconsistent with the wishes of patients on dialysis but persists due to failure to explore or discuss patient goals, values, and preferences in the context of their serious illness. Fewer than 10% of patients on dialysis report having had a conversation about goals, values, and preferences with their nephrologist, although nearly 90% report wanting this conversation. Many nephrologists shy away from these conversations, because they do not wish to upset their patients, feel that there is too much uncertainty in their ability to predict prognosis, are insecure in their skills at broaching the topic, or have difficulty incorporating the conversations into their clinical workflow. In multiple studies, timely discussions about serious illness care goals, however, have been associated with enhanced goal-consistent care, improved quality of life, and positive family outcomes without an increase in patient distress or anxiety. In this special feature article, we will (1) identify the barriers to serious illness conversations in the dialysis population, (2) review best practices in and specific approaches to conducting serious illness conversations, and (3) offer solutions to overcome barriers as well as practical advice, including specific language and tools, to implement serious illness conversations in the dialysis population. PMID:28031417

Factors Affecting Time to Sputum Culture Conversion in Adults with Pulmonary Tuberculosis: A Historical Cohort Study without Censored Cases.

PubMed

Kanda, Rie; Nagao, Taishi; Tho, Nguyen Van; Ogawa, Emiko; Murakami, Yoshitaka; Osawa, Makoto; Saika, Yoshinori; Doi, Kenji; Nakano, Yasutaka

2015-01-01

In patients with pulmonary tuberculosis (TB), shortening the time to sputum culture conversion is desirable to reduce the likelihood of mycobacterial transmission. A persistent positive sputum culture after 2 months of treatment is reported to be associated with the presence of cavitation and the extent of disease on chest X-ray, high colony count, diabetes mellitus, and smoking. However, little is known about factors affecting the time to sputum culture conversion. This study was conducted to evaluate factors affecting the time to sputum culture conversion throughout the course of treatment in adults with pulmonary TB. This study was performed using a database of the medical records of patients with active pulmonary TB who were treated at Hirakata Kohsai Hospital in Hirakata City, Osaka, Japan, from October 2000 to October 2002. Cox proportional-hazards analysis was used to evaluate factors affecting the time to sputum culture conversion after adjusting for potential confounders. The data of 86 patients with pulmonary TB were analyzed. The median time to sputum culture conversion was 39 days, and the maximum time was 116 days. The Cox proportional-hazards analysis showed that a higher smear grading (HR, 0.40; 95%CI, 0.23-0.71) and a history of ever smoking (HR, 0.48; 95%CI, 0.25-0.94) were associated with delayed sputum culture conversion. High smear grading and smoking prolonged the time to sputum culture conversion in adults with pulmonary TB. To effectively control TB, measures to decrease the cigarette smoking rate should be implemented, in addition to early detection and timely anti-TB treatment.

Concentration-Dependent Antagonism and Culture Conversion in Pulmonary Tuberculosis

PubMed Central

Pasipanodya, Jotam G.; Denti, Paolo; Sirgel, Frederick; Lesosky, Maia; Gumbo, Tawanda; Meintjes, Graeme; McIlleron, Helen; Wilkinson, Robert J.

2017-01-01

Abstract Background. There is scant evidence to support target drug exposures for optimal tuberculosis outcomes. We therefore assessed whether pharmacokinetic/pharmacodynamic (PK/PD) parameters could predict 2-month culture conversion. Methods. One hundred patients with pulmonary tuberculosis (65% human immunodeficiency virus coinfected) were intensively sampled to determine rifampicin, isoniazid, and pyrazinamide plasma concentrations after 7–8 weeks of therapy, and PK parameters determined using nonlinear mixed-effects models. Detailed clinical data and sputum for culture were collected at baseline, 2 months, and 5–6 months. Minimum inhibitory concentrations (MICs) were determined on baseline isolates. Multivariate logistic regression and the assumption-free multivariate adaptive regression splines (MARS) were used to identify clinical and PK/PD predictors of 2-month culture conversion. Potential PK/PD predictors included 0- to 24-hour area under the curve (AUC0-24), maximum concentration (Cmax), AUC0-24/MIC, Cmax/MIC, and percentage of time that concentrations persisted above the MIC (%TMIC). Results. Twenty-six percent of patients had Cmax of rifampicin <8 mg/L, pyrazinamide <35 mg/L, and isoniazid <3 mg/L. No relationship was found between PK exposures and 2-month culture conversion using multivariate logistic regression after adjusting for MIC. However, MARS identified negative interactions between isoniazid Cmax and rifampicin Cmax/MIC ratio on 2-month culture conversion. If isoniazid Cmax was <4.6 mg/L and rifampicin Cmax/MIC <28, the isoniazid concentration had an antagonistic effect on culture conversion. For patients with isoniazid Cmax >4.6 mg/L, higher isoniazid exposures were associated with improved rates of culture conversion. Conclusions. PK/PD analyses using MARS identified isoniazid Cmax and rifampicin Cmax/MIC thresholds below which there is concentration-dependent antagonism that reduces 2-month sputum culture conversion. PMID:28205671

The effect of biofouling in simulated Ocean Thermal Energy Conversion (OTEC) evaporator tubes at a potential site in Puerto Rico

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sasscer, D.S.; Morgan, T.O.; Tosteson, T.R.

1980-12-01

Since 29 January 1980, continuous flow of ocean surface water has been maintained through simulated Ocean Thermal Energy Conversion (OTEC) evaporator tubes in order to determine in situ, long-term effects of microbiofouling on heat exchanger efficiency. The experimental apparatus consists of two aluminum and two titanium modules mounted on a research platform moored at the potential OTEC site off Punta Tuna, Puerto Rico. The fouling resistance (R /SUB f/ ), a relative measure of heat transfer efficiency, is being monitored regularly, and the units have been cleaned four times. Postcleaning fouling rates (dR /SUB f/ /dt) for the aluminum unitsmore » have not changed significantly but are considerably higher than the initial fouling rates. At first, post-cleaning fouling rates for the titanium units were less than for the aluminum units, but this value has been progressively increasing and now all units are fouling at approximately the same rate. Cleaning with manually operated M.A.N. brushes did not reduce R /SUB f/ to zero. On four occasions, flow velocity through the units has been increased. Results from these experiments suggest that initially the fouling layer is easily dislodged from the tube surface but that, with time, it becomes more firmly attached.« less

Linear constraint relations in biochemical reaction systems: I. Classification of the calculability and the balanceability of conversion rates.

PubMed

van der Heijden, R T; Heijnen, J J; Hellinga, C; Romein, B; Luyben, K C

1994-01-05

Measurements provide the basis for process monitoring and control as well as for model development and validation. Systematic approaches to increase the accuracy and credibility of the empirical data set are therefore of great value. In (bio)chemical conversions, linear conservation relations such as the balance equations for charge, enthalpy, and/or chemical elements, can be employed to relate conversion rates. In a pactical situation, some of these rates will be measured (in effect, be calculated directly from primary measurements of, e.g., concentrations and flow rates), as others can or cannot be calculated from the measured ones. When certain measured rates can also be calculated from other measured rates, the set of equations, the accuracy and credibility of the measured rates can indeed be improved by, respectively, balancing and gross error diagnosis. The balanced conversion rates are more accurate, and form a consistent set of data, which is more suitable for further application (e.g., to calculate nonmeasured rates) than the raw measurements. Such an approach has drawn attention in previous studies. The current study deals mainly with the problem of mathematically classifying the conversion rates into balanceable and calculable rates, given the subset of measured rates. The significance of this problem is illustrated with some examples. It is shown that a simple matrix equation can be derived that contains the vector of measured conversion rates and the redundancy matrix R. Matrix R plays a predominant role in the classification problem. In supplementary articles, significance of the redundancy matrix R for an improved gross error diagnosis approach will be shown. In addition, efficient equations have been derived to calculate the balanceable and/or calculable rates. The method is completely based on matrix algebra (principally different from the graph-theoretical approach), and it is easily implemented into a computer program. (c) 1994 John Wiley & Sons, Inc.

The nutritional effect of Moringa oleifera fresh leaves as feed supplement on Rhode Island Red hen egg production and quality.

PubMed

Abou-Elezz Fouad Mohammed, Khaled; Sarmiento-Franco, Luis; Santos-Ricalde, Ronald; Solorio-Sanchez, Javier Francisco

2012-06-01

This study aimed to evaluate the potential of Moringa oleifera fresh leaves (MOL) as feed supplement on the performance and egg quality of Rhode Island Red (RIR) hens under the tropical conditions of Yucatan, Mexico. Forty-eight RIR hens were allocated in 12 floor pen replicates each with four birds. Thereafter, the replicates were divided into three groups which were corresponded to ad libitum feed (control), ad libitum feed supplemented with MOL T1 (AL + MOL) and restricted feed amount (20% lower than control) with MOL T2 (RCD + MOL), respectively. T1 (AL + MOL) had higher egg laying rate (71.4% versus 66.6%), higher daily egg mass production (45.4 versus 41.9 g/day), lower feed intake (121.3 versus 127.5 g/day) and better feed conversion ratio (2.8 versus 3.2 g feed:g egg) versus control. T2 / (RCD + MOL) had lower values of body weight, egg laying rate, egg weight and egg mass, and recorded better feed conversion ratio than the control group. The control group recorded a higher percentage of pecked eggs versus T1 and T2 (6.5% versus 1.2% and 2.0 %). Similar intake of MOL (3.1 and 3.4 g DM/day) was recorded in T1 (AL + MOL) and T2 (RCD + MOL). Yolk color was improved significantly in T1 (AL + MOL) than both control and T2 (RCD + MOL), while T2 (RCD + MOL) had eggs with lower yolk and higher albumen percentages than the other two ad libitum groups. The results suggest that MOL could be used successfully as sustainable tropical feed resource for RIR hens.

A 12-bit high-speed column-parallel two-step single-slope analog-to-digital converter (ADC) for CMOS image sensors.

PubMed

Lyu, Tao; Yao, Suying; Nie, Kaiming; Xu, Jiangtao

2014-11-17

A 12-bit high-speed column-parallel two-step single-slope (SS) analog-to-digital converter (ADC) for CMOS image sensors is proposed. The proposed ADC employs a single ramp voltage and multiple reference voltages, and the conversion is divided into coarse phase and fine phase to improve the conversion rate. An error calibration scheme is proposed to correct errors caused by offsets among the reference voltages. The digital-to-analog converter (DAC) used for the ramp generator is based on the split-capacitor array with an attenuation capacitor. Analysis of the DAC's linearity performance versus capacitor mismatch and parasitic capacitance is presented. A prototype 1024 × 32 Time Delay Integration (TDI) CMOS image sensor with the proposed ADC architecture has been fabricated in a standard 0.18 μm CMOS process. The proposed ADC has average power consumption of 128 μW and a conventional rate 6 times higher than the conventional SS ADC. A high-quality image, captured at the line rate of 15.5 k lines/s, shows that the proposed ADC is suitable for high-speed CMOS image sensors.

Effects of naturalistic cell phone conversations on driving performance.

PubMed

Rakauskas, Michael E; Gugerty, Leo J; Ward, Nicholas J

2004-01-01

The prevalence of automobile drivers talking on cell phones is growing, but the effect of that behavior on driving performance is unclear. Also unclear is the relationship between the difficulty level of a phone conversation and the resulting distraction. This study used a driving simulator to determine the effect that easy and difficult cell phone conversations have on driving performance. Cell phone use caused participants to have higher variation in accelerator pedal position, drive more slowly with more variation in speed, and report a higher level of workload regardless of conversation difficulty level. Drivers may cope with the additional stress of phone conversations by enduring higher workloads or setting reduced performance goals. Because an increasing number of people talk on the phone while driving, crashes caused by distracted drivers using cell phones will cause disruptions in business, as well as injury, disability, and permanent loss of personnel.

Improving Donor Conversion Rates at a Level One Trauma Center: Impact of Best Practice Guidelines.

PubMed

Alban, Rodrigo F; Gibbons, Bobby L; Bershad, Vanessa L

2016-11-22

Organ availability is a consistently limiting factor in transplant surgery. A primary driver of this limitation is donor conversion rate, which is defined as the percentage of eligible donors for whom procurement is actually performed. An alternative way to increase organ availability is through improved utilization of organs from donors after cardiac death (DCD). Recently, a concerted, multidisciplinary effort has been made within our system to improve conversion rates and DCD utilization, thus increasing organ availability. Retrospective analysis of a prospectively collected database from TransLife, our local organ procurement organization (OPO), as well as the Orlando Regional Medical Center (ORMC) trauma registry, from 2009-2012 (up to 2013 for DCD). During which time, this organization implemented best practice guidelines to improve conversions and DCD utilization. We analyzed yearly conversion rates, DCD donations and population demographics before and after implementation of these policies. During the study period, donor conversion rates significantly improved from 58% in 2009 to 82% percent in 2012 hospital-wide (P<0.05); and from 50% in 2009 to 81% in 2012 among trauma patients alone (P<0.05). In addition, total organs transplanted increased from 13 to 31 organs (P<0.05) after implementation of best practice guidelines. No significant differences in trauma population demographics were noted during the study period. Based on our experience, the establishment of best practice policies for referral of potential donors, coupled with programs to educate hospital staff on the existence and importance of these policies, leads to significant improvement in donor conversion rates and increased utilization of DCD donors.

Who is at risk of death from nephrectomy? An analysis of thirty-day mortality after 21 380 nephrectomies in 3 years of the British Association of Urological Surgeons (BAUS) National Nephrectomy Audit.

PubMed

Fernando, Archie; Fowler, Sarah; Van Hemelrijck, Mieke; O'Brien, Tim

2017-09-01

To ascertain contemporary overall and differential thirty-day mortality (TDM) rates after all types of nephrectomy in the UK, and to identify potential new risk factors for death. We conducted a retrospective analysis of the 110 deaths that occurred within 30 days of surgery out of the total of 21 380 nephrectomies performed, and calculated the odds ratio (OR) and 95% confidence interval (CI) for TDM based on peri-operative characteristics. The overall TDM rate was 110/21380 (0.5%). The TDM rates after radical, partial, simple nephrectomy and nephro-ureterectomy were 0.6% (63/11057), 0.1% (4/3931), 0.4% (11/2819) and 0.9% (28/3091), respectively. TDM increased with age, stage, estimated blood loss (EBL), operating time and performance status. EBL of 1-2 L was associated with a greater risk of TDM than EBL of 2-5 L (OR 1.38; 95% CI 1.03-2.24). Conversion from minimally invasive surgery was associated with higher risk than non-conversion (OR 2.53; 95% CI 1.14-4.51. Curative surgery was safer than cytoreductive surgery (OR 0.31; 95% CI 0.18-0.54). There was an association between surgical volume and TDM. This study provides contemporary insights into the true risks of all types of nephrectomy. The TDM rate after nephrectomy in the UK appears acceptably low at 0.5%. Established risk factors were confirmed and the following novel risk factors were identified: modest EBL (1-2 L) and conversion from minimally invasive surgery. © 2017 The Authors BJU International © 2017 BJU International Published by John Wiley & Sons Ltd.

Conversion of carbon dioxide to carbon monoxide by pulse dielectric barrier discharge plasma

NASA Astrophysics Data System (ADS)

Wang, Taobo; Liu, Hongxia; Xiong, Xiang; Feng, Xinxin

2017-01-01

The conversion of carbon dioxide (CO2) to carbon monoxide (CO) was investigated in a non-thermal plasma dielectric barrier discharge (DBD) reactor, and the effects of different process conditions on the CO2 conversion were investigated. The results showed that the increase of input power could optimize the conversion of CO2 to CO. The CO2 conversion and CO yield were negatively correlated with the gas flow rate, but there was an optimum gas flow rate, that made the CO selectivity best. The carrier gas (N2, Ar) was conducive to the conversion of CO2, and the effect of N2 as carrier gas was better than Ar. The conversion of CO2 to CO was enhanced by addition of the catalyst (5A molecular sieve).

Conversational Interaction and the Development of Conversational Competence in Additional Languages in Higher Education: Considerations for Students, Language Centres, and Language Policy Developers

ERIC Educational Resources Information Center

Meyer, Stephan; Blondel, Valérie; Mall-Grob, Beatrice

2017-01-01

This article addresses the questions: why is the development of conversational competence important within higher education? And how might this goal be pursued? We offer answers that may aid a broad range of stakeholders (language learners, course designers, lecturers, language development managers, and policy makers) in thinking through these…

Rapid charging of thermal energy storage materials through plasmonic heating.

PubMed

Wang, Zhongyong; Tao, Peng; Liu, Yang; Xu, Hao; Ye, Qinxian; Hu, Hang; Song, Chengyi; Chen, Zhaoping; Shang, Wen; Deng, Tao

2014-09-01

Direct collection, conversion and storage of solar radiation as thermal energy are crucial to the efficient utilization of renewable solar energy and the reduction of global carbon footprint. This work reports a facile approach for rapid and efficient charging of thermal energy storage materials by the instant and intense photothermal effect of uniformly distributed plasmonic nanoparticles. Upon illumination with both green laser light and sunlight, the prepared plasmonic nanocomposites with volumetric ppm level of filler concentration demonstrated a faster heating rate, a higher heating temperature and a larger heating area than the conventional thermal diffusion based approach. With controlled dispersion, we further demonstrated that the light-to-heat conversion and thermal storage properties of the plasmonic nanocomposites can be fine-tuned by engineering the composition of the nanocomposites.

Rapid Charging of Thermal Energy Storage Materials through Plasmonic Heating

PubMed Central

Wang, Zhongyong; Tao, Peng; Liu, Yang; Xu, Hao; Ye, Qinxian; Hu, Hang; Song, Chengyi; Chen, Zhaoping; Shang, Wen; Deng, Tao

2014-01-01

Direct collection, conversion and storage of solar radiation as thermal energy are crucial to the efficient utilization of renewable solar energy and the reduction of global carbon footprint. This work reports a facile approach for rapid and efficient charging of thermal energy storage materials by the instant and intense photothermal effect of uniformly distributed plasmonic nanoparticles. Upon illumination with both green laser light and sunlight, the prepared plasmonic nanocomposites with volumetric ppm level of filler concentration demonstrated a faster heating rate, a higher heating temperature and a larger heating area than the conventional thermal diffusion based approach. With controlled dispersion, we further demonstrated that the light-to-heat conversion and thermal storage properties of the plasmonic nanocomposites can be fine-tuned by engineering the composition of the nanocomposites. PMID:25175717

Differential effects of the mismatch repair genes MSH2 and MSH3 on homeologous recombination in Saccharomyces cerevisiae.

PubMed

Selva, E M; Maderazo, A B; Lahue, R S

1997-12-01

The products of the yeast mismatch repair genes MSH2 and MSH3 participate in the inhibition of genetic recombination between homeologous (divergent) DNA sequences. In strains deficient for these genes, homeologous recombination rates between repeated elements are elevated due to the loss of this inhibition. In this study, the effects of these mutations were further analyzed by quantitation of mitotic homeologous recombinants as crossovers, gene conversions or exceptional events in wild-type, msh2, msh3 and msh2 msh3 mutant strains. When homeologous sequences were present as a direct repeat in one orientation, crossovers and gene conversions were elevated in msh2, msh3 and msh2 msh3 strains. The increases were greater in the msh2 msh3 double mutant than in either single mutant. When the order of the homeologous sequences was reversed, the msh2 mutation again yielded increased rates of crossovers and gene conversions. However, in an msh3 strain, gene conversions occurred at higher levels but interchromosomal crossovers were not increased and intrachromosomal crossovers were reduced relative to wild type. The msh2 msh3 double mutant behaved like the msh2 single mutant in this orientation. Control strains harboring homologous duplications were largely but not entirely unaffected in mutant strains, suggesting specificity for the mismatched intermediates of homeologous recombination. In all strains, very few (< 10%) recombinants could be attributed to exceptional events. These results suggest that MSH2 and MSH3 can function differentially to control homeologous exchanges.

Reconnection in Compressible Plasmas: Extended Conversion Region

NASA Technical Reports Server (NTRS)

Birn, J.; Hesse, M.; Zenitani, S.

2011-01-01

The classical Sweet-Parker approach to steady-state magnetic reconnection is extended into the regime of large resistivity (small magnetic Reynolds or Lundquist number) when the aspect ratio between the outflow and inflow scale, delta = d/L, approaches unity. In a previous paper the vicinity of the dissipation site ("diffusion region") was investigated. In this paper, the approach is extended to cover larger sites, in which the energy transfer and conversion is not confined to the diffusion region. Consistent with the results of Paper I, we find that increasing aspect ratio delta is associated with increasing compression, increasing reconnect ion rate for low Beta, but slightly decreasing rate for higher Beta, decreasing outflow speed, and increasing outflow magnetic field. These trends are stronger for lower Beta. Deviations from the traditional Sweet-Parker limit delta approaches 0 become significant for R(sub m) approx < 10, where R(sub m) is the magnetic Reynolds number (Lundquist number) based on the half-thickness of the current layer responsible for the Ohmic dissipation. They are also more significant for small gamma, that is, for increasing compressibility. In contrast to the results of Paper I, but consistent with earlier results for delta much < 1,nu(sub A) we find that in this limit the outflow speed is given by the Alfven speed nu(sub A) in the inflow region and the energy conversion is given by an even split of Poynting flux into enthalpy flux and bulk kinetic energy flux. However, with increasing delta the conversion to enthalpy flux becomes more and more dominant.

OPTN/SRTR 2013 Annual Data Report: deceased organ donation.

PubMed

Israni, A K; Zaun, D A; Rosendale, J D; Snyder, J J; Kasiske, B L

2015-01-01

The status of deceased organ donation is assessed using metrics such as donation/conversation rate, organ yield, and rate of organs recovered for transplant and not transplanted. These metrics are based on eligible deaths (brain death of a person aged 70 years or younger) as well as on actual donors. The 9132 eligible deaths reported in 2013 represented a slight increase over 2012. The donation/conversion rate was 71.3 eligible donors per 100 eligible deaths, a slight decline from 2012, and varied by donation service area from 50.0 to 87.0. The number of organs recovered per donor, 3.55, also varied by donation service area, from 2.79 to 4.10. The mean number of organs transplanted per donor was 3.08 in 2013, slightly higher than 3.02 in 2012. The mean observed/expected organ yield ratio for kidneys varied from 0.86 to 1.18; for pancreata, from 0.29 to 2.59; for livers, from 0.69 to 1.17; for hearts, from 0.68 to 1.41; and for lungs, from 0.33 to 1.41. The rate of organs recovered for transplant and not transplanted in 2013 for all organs combined was 0.13 per recovered organ, slightly lower than the rate of 0.14 in 2012. © Copyright 2015 The American Society of Transplantation and the American Society of Transplant Surgeons.

Property evolution during vitrification of dimethacrylate photopolymer networks.

PubMed

Abu-elenain, Dalia A; Lewis, Steven H; Stansbury, Jeffrey W

2013-11-01

This study seeks to correlate the interrelated properties of conversion, shrinkage, modulus and stress as dimethacrylate networks transition from rubbery to glassy states during photopolymerization. An unfilled BisGMA/TEGDMA resin was photocured for various irradiation intervals (7-600 s) to provide controlled levels of immediate conversion, which was monitored continuously for 10 min. Fiber optic near-infrared spectroscopy permitted coupling of real-time conversion measurement with dynamic polymerization shrinkage (linometer), modulus (dynamic mechanical analyzer) and stress (tensometer) development profiles. The varied irradiation conditions produced final conversion ranging from 6% to more than 60%. Post-irradiation conversion (dark cure) was quite limited when photopolymerization was interrupted either at very low or very high levels of conversion while significant dark cure contributions were possible for photocuring reactions suspended within the post-gel, rubbery regime. Analysis of conversion-based property evolution during and subsequent to photocuring demonstrated that the shrinkage rate increased significantly at about 40% conversion followed by late-stage suppression in the conversion-dependent shrinkage rate that begins at about 45-50% conversion. The gradual vitrification process over this conversion range is evident based on the broad but well-defined inflection in the modulus versus conversion data. As limiting conversion is approached, modulus and, to a somewhat lesser extent, stress rise precipitously as a result of vitrification with the stress profile showing little if any late-stage suppression as seen with shrinkage. Near the limiting conversion for this model resin, the volumetric polymerization shrinkage rate slows while an exponential rise in modulus promotes the vitrification process that appears to largely dictate stress development. Copyright © 2013 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Comparison of Effects Produced by Nicotine and the α4β2-Selective Agonist 5-I-A-85380 On Intracranial Self-Stimulation in Rats

PubMed Central

Freitas, Kelen; Carroll, F. Ivy; Negus, S. Stevens

2015-01-01

Intracranial self-stimulation (ICSS) is one type of preclinical procedure for research on pharmacological mechanisms that mediate abuse potential of drugs acting at various targets including nicotinic acetylcholine receptors (nAChRs). This study compared effects of the non-selective nAChR agonist nicotine (0.032-1.0 mg/kg) and the α4β2-selective nAChR agonist 5-I-A-85380 (0.01-1.0 mg/kg) on ICSS in male Sprague-Dawley rats. Rats were implanted with electrodes targeting the medial forebrain bundle at the level of the lateral hypothalamus and trained to respond under a fixed-ratio 1 schedule for a range of brain stimulation frequencies (158-56 Hz). A broad range of 5-I-A-85380 doses produced an abuse-related increase (or “facilitation”) of low ICSS rates maintained by low brain-stimulation frequencies, and this effect was blocked by both the nonselective nAChR antagonist mecamylamine and the selective α4β2 antagonist dihyrdo-ß-erythroidine (DHßE). Conversely, nicotine produced weaker ICSS facilitation across a narrower range of doses, and higher nicotine doses decreased high rates of ICSS maintained by high brain- stimulation frequencies. The rate-decreasing effects of a high nicotine dose were blocked by mecamylamine but not DHßE. Chronic nicotine treatment produced selective tolerance to rate-decreasing effects of nicotine but did not alter ICSS rate-increasing effects of nicotine. These results suggest that α4β2 receptors are sufficient to mediate abuse-related rate-increasing effects of nAChR agonists in this ICSS procedure. Conversely, nicotine effects at non-α4β2 nAChRs appear to oppose and limit abuse-related effects mediated by α4β2 receptors, although tolerance can develop to these non-α4β2 effects. Selective α4β2 agonists may have higher abuse potential than nicotine. PMID:26461167

Channel Modeling

NASA Astrophysics Data System (ADS)

Schmitz, Arne; Schinnenburg, Marc; Gross, James; Aguiar, Ana

For any communication system the Signal-to-Interference-plus-Noise-Ratio of the link is a fundamental metric. Recall (cf. Chapter 9) that the SINR is defined as the ratio between the received power of the signal of interest and the sum of all "disturbing" power sources (i.e. interference and noise). From information theory it is known that a higher SINR increases the maximum possible error-free transmission rate (referred to as Shannon capacity [417] of any communication system and vice versa). Conversely, the higher the SINR, the lower will be the bit error rate in practical systems. While one aspect of the SINR is the sum of all distracting power sources, another issue is the received power. This depends on the transmitted power, the used antennas, possibly on signal processing techniques and ultimately on the channel gain between transmitter and receiver.

Temperature field analysis for PZT pyroelectric cells for thermal energy harvesting.

PubMed

Hsiao, Chun-Ching; Ciou, Jing-Chih; Siao, An-Shen; Lee, Chi-Yuan

2011-01-01

This paper proposes the idea of etching PZT to improve the temperature variation rate of a thicker PZT sheet in order to enhance the energy conversion efficiency when used as pyroelectric cells. A partially covered electrode was proven to display a higher output response than a fully covered electrode did. A mesh top electrode monitored the temperature variation rate and the electrode area. The mesh electrode width affected the distribution of the temperature variation rate in a thinner pyroelectric material. However, a pyroelectric cell with a thicker pyroelectric material was beneficial in generating electricity pyroelectrically. The PZT sheet was further etched to produce deeper cavities and a smaller electrode width to induce lateral temperature gradients on the sidewalls of cavities under homogeneous heat irradiation, enhancing the temperature variation rate.

Temperature Field Analysis for PZT Pyroelectric Cells for Thermal Energy Harvesting

PubMed Central

Hsiao, Chun-Ching; Ciou, Jing-Chih; Siao, An-Shen; Lee, Chi-Yuan

2011-01-01

This paper proposes the idea of etching PZT to improve the temperature variation rate of a thicker PZT sheet in order to enhance the energy conversion efficiency when used as pyroelectric cells. A partially covered electrode was proven to display a higher output response than a fully covered electrode did. A mesh top electrode monitored the temperature variation rate and the electrode area. The mesh electrode width affected the distribution of the temperature variation rate in a thinner pyroelectric material. However, a pyroelectric cell with a thicker pyroelectric material was beneficial in generating electricity pyroelectrically. The PZT sheet was further etched to produce deeper cavities and a smaller electrode width to induce lateral temperature gradients on the sidewalls of cavities under homogeneous heat irradiation, enhancing the temperature variation rate. PMID:22346652

Efficient electrochemical CO 2 conversion powered by renewable energy

DOE PAGES

Kauffman, Douglas R.; Thakkar, Jay; Siva, Rajan; ...

2015-06-29

Here, the catalytic conversion of CO 2 into industrially relevant chemicals is one strategy for mitigating greenhouse gas emissions. Along these lines, electrochemical CO 2 conversion technologies are attractive because they can operate with high reaction rates at ambient conditions. However, electrochemical systems require electricity, and CO 2 conversion processes must integrate with carbon-free, renewable-energy sources to be viable on larger scales. We utilize Au 25 nanoclusters as renewably powered CO 2 conversion electrocatalysts with CO 2 → CO reaction rates between 400 and 800 L of CO 2 per gram of catalytic metal per hour and product selectivities betweenmore » 80 and 95%. These performance metrics correspond to conversion rates approaching 0.8–1.6 kg of CO 2 per gram of catalytic metal per hour. We also present data showing CO 2 conversion rates and product selectivity strongly depend on catalyst loading. Optimized systems demonstrate stable operation and reaction turnover numbers (TONs) approaching 6 × 10 6 mol CO 2 molcatalyst–1 during a multiday (36 hours total hours) CO 2electrolysis experiment containing multiple start/stop cycles. TONs between 1 × 10 6 and 4 × 10 6 molCO 2 molcatalyst–1 were obtained when our system was powered by consumer-grade renewable-energy sources. Daytime photovoltaic-powered CO 2 conversion was demonstrated for 12 h and we mimicked low-light or nighttime operation for 24 h with a solar-rechargeable battery. This proof-of-principle study provides some of the initial performance data necessary for assessing the scalability and technical viability of electrochemical CO 2 conversion technologies. Specifically, we show the following: (1) all electrochemical CO 2 conversion systems will produce a net increase in CO 2 emissions if they do not integrate with renewable-energy sources, (2) catalyst loading vs activity trends can be used to tune process rates and product distributions, and (3) state-of-the-art renewable-energy technologies are sufficient to power larger-scale, tonne per day CO 2 conversion systems.« less

The Epoch of Disk Formation: z is Approximately l to Today

NASA Technical Reports Server (NTRS)

Kassin, Susan; Gardner, Jonathan; Weiner, Ben; Faber, Sandra

2012-01-01

We present data on galaxy kinematics, morphologies, and star-formation rates over 0.1 less than z less than 1.2 for approximately 500 blue galaxies. These data show how systems like our own Milky-Way have come into being. At redshifts around 1, about half the age of the Universe ago, Milky-Way mass galaxies were different beasts than today. They had a significant amount of disturbed motions, disturbed morphologies, shallower potential wells, higher specific star-formation rates, and likely higher gas fractions. Since redshift approximately 1, galaxies have decreased in disturbed motions, increased in rotation velocity and potential well depth, become more well-ordered morphologically, and decreased in specific star-formation rate. We find interrelationships between these measurements. Galaxy kinematics are correlated with morphology and specific star-formation rate such that galaxies with the fastest rotation velocities and the least amounts of disturbed motions have the most well-ordered morphologies and the lowest specific star-formation rates. The converse is true. Moreover, we find that the rate at which galaxies become more well-ordered kinematically (i.e., increased rotation velocity, decreased disturbed motions) and morphologically is directly proportional to their stellar mass.

Method to monitor HC-SCR catalyst NOx reduction performance for lean exhaust applications

DOEpatents

Viola, Michael B [Macomb Township, MI; Schmieg, Steven J [Troy, MI; Sloane, Thompson M [Oxford, MI; Hilden, David L [Shelby Township, MI; Mulawa, Patricia A [Clinton Township, MI; Lee, Jong H [Rochester Hills, MI; Cheng, Shi-Wai S [Troy, MI

2012-05-29

A method for initiating a regeneration mode in selective catalytic reduction device utilizing hydrocarbons as a reductant includes monitoring a temperature within the aftertreatment system, monitoring a fuel dosing rate to the selective catalytic reduction device, monitoring an initial conversion efficiency, selecting a determined equation to estimate changes in a conversion efficiency of the selective catalytic reduction device based upon the monitored temperature and the monitored fuel dosing rate, estimating changes in the conversion efficiency based upon the determined equation and the initial conversion efficiency, and initiating a regeneration mode for the selective catalytic reduction device based upon the estimated changes in conversion efficiency.

"Hunger Hurts, but Starving Works". The Moral Conversion to Eating Disorders.

PubMed

Orsini, Gisella

2017-03-01

This article aims to shed light on the self-perceptions of people with eating disorders in Malta and Italy through a deep understanding of their narratives. In contrast to the biomedical perception of the phenomenon and in opposition with the prevalent feminist theories on the subject, I consider eating disorders as the result of self-transformative processes. I suggest that anorexics, bulimics and binge eaters are actively and deliberately engaged in a project of moral self-transformation that is culturally defined. The moral transformations of women with eating disorders in Malta and Italy, the two considered contexts of this research, reflect the social expectations of women in these societies. The drastic changes in personal attitudes towards both food and the body that characterise eating disorders are the result of a complete dedication to the moral values embodied in thinness, namely the control of bodily needs and pleasure. The self-transformative process of people with eating disorders can be understood as a form of moral conversion along a continuum of increasing control over hunger: the higher the control, the higher the level of satisfaction and the degree of moral conversion achieved. Considering the general low recovery rates of people with eating disorders, this approach helps in the understanding of why people who are diagnosed with an eating disorder accept medical definitions and treatments to different extents.

Guar meal ameliorates Eimeria tenella infection in broiler chicks.

PubMed

Hassan, Sherif M; El-Gayar, Amal K; Cadwell, David J; Bailey, Christopher A; Cartwright, Aubrey L

2008-10-20

Guar meal contains relatively high levels of saponins, which are known to have antiprotozoal activity and may be effective against coccidiosis. A 2x2 factorial experiment investigated the impact of guar meal (0 or 5%) corn-soy-based starter broiler diets on chicks unchallenged or challenged with Eimeria tenella. At 1 day of age, 120 unsexed RossxRoss broiler chicks were randomly distributed among four treatment groups. Chicks were challenged with 5x10(3) sporulated oocysts of E. tenella in 0.5 ml at 10 days of age by oral gavage. Weekly body weight, body weight gains, feed conversion ratio and mortality rate were recorded for chicks fed from 0 to 21 days of age. Oocysts shed per gram feces were recorded from 6 to 10 days post-challenge. Results showed that challenged chicks fed 0% guar meal had significantly higher oocysts per gram shed in feces than the other groups. No significant differences among treatment groups in mortality rate were observed. Body weights of unchallenged and challenged chicks fed 0% guar meal were significantly higher than those fed 5% guar meal at 2 weeks of age. Results indicated that including 5% guar meal in the diet of chicks challenged with E. tenella decreased oocysts shed per gram feces and prevented bloody diarrhea, but without affects on body weight and feed conversion ratio at 11 days post-challenge.

Parent-Adolescent Conversations about Eating, Physical Activity and Weight: Prevalence across Sociodemographic Characteristics and Associations with Adolescent Weight and Weight-Related Behaviors

PubMed Central

Berge, Jerica M.; MacLehose, Richard F; Loth, Katie A.; Eisenberg, Marla E.; Fulkerson, Jayne A.; Neumark-Sztainer, Dianne

2015-01-01

This paper aims to describe the prevalence of parent-adolescent conversations about eating, physical activity and weight across sociodemographic characteristics and to examine associations with adolescent BMI, dietary intake, physical activity and sedentary behaviors. Data from two linked epidemiological studies were used for cross-sectional analysis. Parents (n=3,424; 62% females) and adolescents (n=2,182; 53.2% girls) were socioeconomically and racially/ethnically diverse. Fathers reported more parent-adolescent conversations about healthful eating and physical activity with their sons and mothers reported more weight-focused conversations with their daughters. Parents of Hispanic/Latino and Asian/Hmong youth and parents from lower SES categories engaged in more conversations about weight and size. Adolescents whose mothers or fathers had weight-focused conversations with them had higher BMI percentiles. Adolescents who had two parents engaging in weight-related conversations had higher BMI percentiles. Healthcare providers may want to talk about the types of weight-related conversations parents are having with their adolescents and emphasize avoiding conversations about weight specifically. PMID:24997555

5 CFR 536.305 - Adjusting an employee's retained rate when a pay schedule is adjusted.

Code of Federal Regulations, 2010 CFR

2010-01-01

... conversion under § 536.303(b) or any other simultaneous pay action. The retained rate adjustment under... new retained rate must be determined under the geographic conversion rule in § 536.303(b). (4... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Adjusting an employee's retained rate...

Mycobacterium tuberculosis transmission rates in a sanatorium: implications for new preventive guidelines.

PubMed

Jernigan, J A; Adal, K A; Anglim, A M; Byers, K E; Farr, B M

1994-12-01

In 1990, the Centers for Disease Control and Prevention recommended substituting dust-mist particulate respirators for simple isolation masks in acid-fast bacillus isolation rooms, reasoning that air leaks around the simple masks could result in a higher rate of purified protein derivative skin-test conversion. In 1993, a Centers for Disease Control and Prevention draft guideline proposed that high-efficiency particulate air filter respirators be used instead of dust-mist particulate respirators. Epidemiologic data were not available to assess the importance of these changes or their cost-effectiveness. The University of Virginia was affiliated with a tuberculosis hospital from 1979 until 1987. We surveyed physicians who had served as residents in internal medicine during this period regarding purified protein derivative skin-test history. duration of work at the tuberculosis sanatorium, and any history of unprotected exposures to patients with active pulmonary or laryngeal tuberculosis. Patients with active tuberculosis at the sanatorium were isolated in negative-pressure rooms with UV lights. Physicians wore simple isolation masks in these rooms. Responses were received from 83 former resident physicians. Fifty-two physicians had worked on the tuberculosis wards for a total of 420 weeks, with no subsequent skin-test conversions (95% CI 0 to 1 conversion/8 physician-years). These data document a low risk of occupational transmission of Mycobacterium tuberculosis to physicians who wear simple isolation masks in negative-pressure ventilation rooms with UV lights. This low rate predicts that the additional protective efficacy and cost-effectiveness of the more expensive high-efficiency particulate air filter respirators and the respiratory protection program will be low.

Effect of temperature on reduction of CaSO{sub 4} oxygen carrier in chemical-looping combustion of simulated coal gas in a fluidized bed reactor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Song, Q.L.; Xiao, R.; Deng, Z.Y.

2008-12-15

Chemical-looping combustion (CLC) is a promising combustion technology for gaseous and solid fuel with efficient use of energy and inherent separation of CO{sub 2}. The concept of a coal-fueled CLC system using, calcium sulfate (CaSO{sub 4}) as oxygen carrier is proposed in this study. Reduction tests of CaSO{sub 4} oxygen carrier with simulated coal gas were performed in a laboratory-scale fluidized bed reactor in the temperature range of 890-950{degree}C. A high concentration of CO{sub 2} was obtained at the initial reduction period. CaSO{sub 4} oxygen carrier exhibited high reactivity initially and decreased gradually at the late period of reduction. Themore » sulfur release during the reduction of CaSO{sub 4} as oxygen carrier was also observed and analyzed. H{sub 2} and CO{sub 2} conversions were greatly influenced by reduction temperature. The oxygen carrier conversion and mass-based reaction rates during the reduction at typical temperatures were compared. Higher temperatures would enhance reaction rates and result in high conversion of oxygen carrier. An XRD patterns study indicated that CaS was the dominant product of reduction and the variation of relative intensity with temperature is in agreement with the solid conversion. ESEM analysis indicated that the surface structure of oxygen carrier particles changed significantly from impervious to porous after reduction. EDS analysis also demonstrated the transfer of oxygen from the oxygen carrier to the fuel gas and a certain amount of sulfur loss and CaO formation on the surface at higher temperatures. The reduction kinetics of CaSO{sub 4} oxygen carrier was explored with the shrinking unreacted-core model. The apparent kinetic parameters were obtained, and the kinetic equation well predicted the experimental data. Finally, some basic considerations on the use of CaSO{sub 4} oxygen carrier in a CLC system for solid fuels were discussed.« less

Inclusion criteria provide heterogeneity in baseline profiles of patients with mild cognitive impairment: comparison of two prospective cohort studies

PubMed Central

Kawashima, Shoji; Kato, Takashi

2012-01-01

Background Mild cognitive impairment (MCI) is considered to represent a transitional stage between ageing and Alzheimer's disease (AD). To aim at identifying neuroimaging measures associated with cognitive changes in healthy elderly and MCI patients, longitudinal multicentre studies are ongoing in several countries. The patient profiles of each study are based on unique inclusion criteria. Objectives The purpose of the study is to clarify differences in baseline profiles of MCI patients between Studies on Diagnosis of Early Alzheimer's Disease—Japan (SEAD-J) and Alzheimer's Disease Neuroimaging Initiative (ADNI) and to examine the association between baseline profiles and risk of early conversion to AD. Design Prospective cohort study. Setting and participants SEAD-J recruited 114 patients from nine facilities in Japan. A total of 200 patients in ADNI with fluorodeoxyglucose–positron emission tomography (FDG-PET) were enrolled from the USA. Methods Baseline profiles were statistically analysed. For FDG-PET at a time of inclusion, associations between each profile and cerebral metabolic rate for glucose (CMRgl) were examined using SPM5 software. In each study, the ratio of conversion to AD within the 1-year and 2-year period after inclusion was investigated and differences in baseline profiles between AD converters and non-converters were analysed. Results SEAD-J included MCI patients with more severe verbal memory deficits and extracted patients with higher depressive tendencies. These differences were likely to be associated with criteria. SEAD-J exhibited a higher rate of conversion within 1 year compared with ADNI (24.5% vs 13.5%). In FDG-PET analyses of SEAD-J, AD converters within 1 year showed more severe decrease of FDG uptake in bilateral inferior parietal regions compared with non-converters. Conclusions Different inclusion criteria provided differences in baseline profiles. The severity of memory deficit might cause increase of the AD conversion within 1 year. Clinical outcomes of multicentre studies for early diagnosis of AD should be interpreted carefully considering profiles of patients. PMID:22535791

Improving Donor Conversion Rates at a Level One Trauma Center: Impact of Best Practice Guidelines

PubMed Central

Gibbons, Bobby L; Bershad, Vanessa L

2016-01-01

Background Organ availability is a consistently limiting factor in transplant surgery. A primary driver of this limitation is donor conversion rate, which is defined as the percentage of eligible donors for whom procurement is actually performed. An alternative way to increase organ availability is through improved utilization of organs from donors after cardiac death (DCD). Recently, a concerted, multidisciplinary effort has been made within our system to improve conversion rates and DCD utilization, thus increasing organ availability. Study design Retrospective analysis of a prospectively collected database from TransLife, our local organ procurement organization (OPO), as well as the Orlando Regional Medical Center (ORMC) trauma registry, from 2009-2012 (up to 2013 for DCD). During which time, this organization implemented best practice guidelines to improve conversions and DCD utilization. We analyzed yearly conversion rates, DCD donations and population demographics before and after implementation of these policies. Results During the study period, donor conversion rates significantly improved from 58% in 2009 to 82% percent in 2012 hospital-wide (P<0.05); and from 50% in 2009 to 81% in 2012 among trauma patients alone (P<0.05). In addition, total organs transplanted increased from 13 to 31 organs (P<0.05) after implementation of best practice guidelines. No significant differences in trauma population demographics were noted during the study period. Conclusions Based on our experience, the establishment of best practice policies for referral of potential donors, coupled with programs to educate hospital staff on the existence and importance of these policies, leads to significant improvement in donor conversion rates and increased utilization of DCD donors. PMID:28018761

Retrospective Conversion of Three Library Collections.

ERIC Educational Resources Information Center

Johnson, Carolyn A.

1982-01-01

Reports on the retrospective conversion via OCLC of cataloging for three library collections at the University of South Carolina--the main, rare book, and historical collections. Backgrounds of the collections, conversion procedures, determinants of conversion rates, and cost factors are discussed. (Author/JL)

Screening employees of services for homeless individuals in Montréal for tuberculosis infection.

PubMed

Isler, M A; Rivest, P; Mason, J; Brassard, P

2013-06-01

The results of a tuberculin skin test (TST) screening program offered to employees of services for homeless people in Montréal from 1998 to 2005 were analyzed to assess the occupational risk of tuberculosis (TB) infection. Employees with no known contact with TB were selected among volunteer participants. They were followed in two dynamic cohorts: individuals with a negative two-step baseline TST (cohort A) and individuals with a negative single baseline TST (cohort B). We estimated the prevalences of initial positive TST, boosting effect, and conversion rate. The average age of the workers was 38.9 years. The prevalence of an initial positive TST was 12.9%. A booster effect was observed in 5.1% of workers who completed a two-step TST. The incidence of conversion was 2.3/100 person-years for cohort A (n=93) and 3.5/100 person-years for cohort B (n=221). The incidence of conversion was not significantly associated with any of the demographics or workplace factors investigated. Our findings are comparable to the rates reported among community workers, whose risk is higher than the average health worker. This suggests that there are occasional unidentified contagious cases among the homeless individuals of participating institutions. Copyright © 2013 King Saud Bin Abdulaziz University for Health Sciences. Published by Elsevier Ltd. All rights reserved.

Fermentation of sugarcane bagasse and chicken manure to calcium carboxylates under thermophilic conditions.

PubMed

Fu, Zhihong; Holtzapple, Mark T

2010-09-01

Sugarcane bagasse and chicken manure were anaerobically fermented to carboxylic acids using a mixed culture of marine microorganisms at 55 degrees C. Using the MixAlco process--an example of consolidated bioprocessing--the resulting carboxylate salts can be converted to mixed alcohol fuels or gasoline. To enhance digestibility, sugarcane bagasse was lime pretreated with 0.1 g Ca(OH)(2)/g dry biomass at 100 degrees C for 2 h. Four-stage countercurrent fermentation of 80% sugarcane bagasse/20% chicken manure was performed at various volatile solids (VS) loading rates and liquid residence times. Calcium carbonate was used as a buffer during fermentation. The highest acid productivity of 0.79 g/(L day) occurred at a total acid concentration of 21.5 g/L. The highest conversion (0.59 g VS digested/g VS fed) and yield (0.18 g total acids/g VS fed) occurred at a total acid concentration of 15.5 g/L. The continuum particle distribution model (CPDM) predicted the experimental total acid concentrations and conversions at an average error of 10.14% and 12.68%, respectively. CPDM optimizations show that high conversion (>80%) and total acid concentration of 21.3 g/L are possible with 300 g substrate/(L liquid), 30 days liquid residence time, and 3 g/(L day) solid loading rate. Thermophilic fermentation has a higher acetate content (approximately 63 wt%) than mesophilic fermentation (approximately 39 wt%).

Influence of light-curing sources on polymerization reaction kinetics of a restorative system.

PubMed

D'Alpino, Paulo H P; Svizero, Nádia R; Pereira, José C; Rueggeberg, Frederick A; Carvalho, Ricardo M; Pashley, David H

2007-02-01

To determine the effect of using a variety of commercial light-curing units on polymerization of a dentin-bonding agent (Adper Single Bond) and of a resin composite (Filtek Z250). Infrared (IR) spectra were obtained kinetically at one scan/second at 2 cm(-1) resolution for a period of 5 minutes and were analyzed for: maximum conversion rate (%/s), time into exposure when maximum rate occurred (seconds), conversion at maximum rate (%), and total conversion (%) at 300 seconds by comparison of aliphatic-to-aromatic absorption IR peak ratios, before and after polymerization. Light units used were: QTH 540 mW/cm2 (XL3000); LED 750 mW/cm2 (Elipar FreeLight 2); PAC 2,130 mW/cm2 (ARC II). Exposure followed manufacturers' recommendations: dentin bonding agent for 10 seconds, RC for 20 seconds (QTH), and 10 seconds (LED and PAC). Polymerization kinetics was evaluated at the bottom surface (2.5 mm thick) for the resin composite and as a thin film for the dentin bonding agent on the diamond surface of an attenuated total reflectance accessory in the IR spectrometer. Values (n = 5) were compared using ANOVA and Tukey's pairwise post-hoc test: pre-set alpha 0.05. PAC produced the highest total conversion and conversion rate for the resin composite (P < 0.05). Total conversion was lower for dentin bonding adhesive using PAC than with LED or QTH (P < 0.05). LED provided the highest proportion of conversion at the maximum rate with respect to conversion at 300 seconds for both materials. QTH demonstrated the lowest maximum rate value that occurred at a longer time into exposure (P < 0.05). Polymerization kinetic parameters varied greatly between the restorative materials as well as among light-curing unit types when compared to values observed when using a QTH light as control.

Self-organization of dissolved organic matter to micelle-like microparticles in river water.

PubMed

Kerner, Martin; Hohenberg, Heinz; Ertl, Siegmund; Reckermann, Marcus; Spitzy, Alejandro

2003-03-13

In aquatic systems, the concept of the 'microbial loop' is invoked to describe the conversion of dissolved organic matter to particulate organic matter by bacteria. This process mediates the transfer of energy and matter from dissolved organic matter to higher trophic levels, and therefore controls (together with primary production) the productivity of aquatic systems. Here we report experiments on laboratory incubations of sterile filtered river water in which we find that up to 25% of the dissolved organic carbon (DOC) aggregates abiotically to particles of diameter 0.4-0.8 micrometres, at rates similar to bacterial growth. Diffusion drives aggregation of low- to high-molecular-mass DOC and further to larger micelle-like microparticles. The chemical composition of these microparticles suggests their potential use as food by planktonic bacterivores. This pathway is apparent from differences in the stable carbon isotope compositions of picoplankton and the microparticles. A large fraction of dissolved organic matter might therefore be channelled through microparticles directly to higher trophic levels--bypassing the microbial loop--suggesting that current concepts of carbon conversion in aquatic systems require revision.

Co-digestion of polylactide and kitchen garbage in hyperthermophilic and thermophilic continuous anaerobic process.

PubMed

Wang, Feng; Hidaka, Taira; Tsuno, Hiroshi; Tsubota, Jun

2012-05-01

Two series of two-phase anaerobic systems, consisting of a hyperthermophilic (80°C) reactor and a thermophilic (55°C) reactor, fed with a mixture of kitchen garbage (KG) and polylactide (PLA), was compared with a single-phase thermophilic reactor for the overall performance. The result indicated that ammonia addition under hyperthermophilic condition promoted the transformation of PLA particles to lactic acid. The systems with hyperthermophilic treatment had advantages on PLA transformation and methane conversion ratio to the control system. Under the organic loading rate (OLR) of 10.3 g COD/(L day), the PLA transformation ratios of the two-phase systems were 82.0% and 85.2%, respectively, higher than that of the control system (63.5%). The methane conversion ratios of the two-phase systems were 82.9% and 80.8%, respectively, higher than 70.1% of the control system. The microbial community analysis indicated that hyperthermophilic treatment is easily installed to traditional thermophilic anaerobic digestion plants without inoculation of special bacteria. Copyright © 2012 Elsevier Ltd. All rights reserved.

Growth efficiency in transgenic tilapia (Oreochromis sp.) carrying a single copy of an homologous cDNA growth hormone.

PubMed

Martínez, R; Juncal, J; Zaldívar, C; Arenal, A; Guillén, I; Morera, V; Carrillo, O; Estrada, M; Morales, A; Estrada, M P

2000-01-07

Growth hormone (GH) has been shown to have a profound impact on fish physiology and metabolism. However, detailed studies in transgenic fish have not been conducted. We have characterized the food conversion efficiency, protein profile, and biochemical correlates of growth rate in transgenic tilapia expressing the tilapia GH cDNA under the control of human cytomegalovirus regulatory sequences. Transgenic tilapia exhibited about 3.6-fold less food consumption than nontransgenic controls (P < 0.001). The food conversion efficiency was significantly (P < 0.05) higher (290%) in transgenic tilapia (2.3 +/- 0.4) than in the control group (0.8 +/- 0.2). Efficiency of growth, synthesis retention, anabolic stimulation, and average protein synthesis were higher in transgenic than in nontransgenic tilapia. Distinctive metabolic differences were found in transgenic juvenile tilapia. We had found differences in hepatic glucose, and in agreement with previous results we observed differences in the level of enzymatic activities in target organs. We conclude that GH-transgenic juvenile tilapia show altered physiological and metabolic conditions and are biologically more efficient. Copyright 2000 Academic Press.

Efficient production of lactulose from whey powder by cellobiose 2-epimerase in an enzymatic membrane reactor.

PubMed

Wu, Lingtian; Xu, Cen; Li, Sha; Liang, Jinfeng; Xu, Hong; Xu, Zheng

2017-06-01

In this study, the gene encoding cellobiose 2-epimerase from Caldicellulosiruptor saccharolyticus (CsCE) was successfully expressed in Bacillus subtilis WB800. After the fermentation medium optimization, the activity of recombinant strain was 4.5-fold higher than the original medium in a 7.5L fermentor. The optimal catalytic pH and temperature of crude CsCE were 7.0 and 80°C, respectively. An enzymatic synthesis of lactulose was developed using cheese-whey lactose as its substrate. The maximum conversion rate of whey powder obtained was 58.5% using 7.5 U/mL CsCE. The enzymatic membrane reactor system exhibited a great operational stability, confirmed with the higher lactose conversion (42.4%) after 10 batches. To our best knowledge, this is the first report of lactulose synthesis in food grade strain, which improve the food safety, and we not only realize the biological production of lactulose, but also make good use of industrial waste, which have positive impact on environment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Impact of temperature and substrate concentration on degradation rates of acetate, propionate and hydrogen and their links to microbial community structure.

PubMed

Zhao, Jing; Westerholm, Maria; Qiao, Wei; Yin, Dongmin; Bi, Shaojie; Jiang, Mengmeng; Dong, Renjie

2018-05-01

The present study investigates the conversion of acetate, propionate and hydrogen consumption linked to the microbial community structure and related to temperature and substrate concentration. Biogas reactors were continuously fed with coffee powder (20 g-COD/L) or acetate (20, 40, and 60 g-COD/L) and operated for 193 days at 37 °C or 55 °C conditions. Starting HRT was 23 days which was then reduced to 7 days. The kinetics of acetate and propionate degradation and hydrogen consumption rates were measured in batch assays. At HRT 7 days, the degradation rate of propionate was higher in thermophilic batches, while acetate degradation rate was higher at mesophilic conditions. The gaseous hydrogen consumption in acetate reactors increased proportionally with temperature and substrate concentration, while the dissolved hydrogen was not affected. The relative high abundance of hydrogentrophic methanogens indicated that the methanogenesis was directed towards the syntrophic acetate oxidation pathway at high acetate concentration and high temperature. Copyright © 2018 Elsevier Ltd. All rights reserved.

Development of factors to convert frequency to rate for β-cell replication and apoptosis quantified by time-lapse video microscopy and immunohistochemistry

PubMed Central

Saisho, Yoshifumi; Manesso, Erica; Gurlo, Tatyana; Huang, Chang-jiang; Toffolo, Gianna M.; Cobelli, Claudio; Butler, Peter C.

2009-01-01

An obstacle to development of methods to quantify β-cell turnover from pancreas tissue is the lack of conversion factors for the frequency of β-cell replication or apoptosis detected by immunohistochemistry to rates of replication or apoptosis. We addressed this obstacle in islets from 1-mo-old rats by quantifying the relationship between the rate of β-cell replication observed directly by time-lapse video microscopy (TLVM) and the frequency of β-cell replication in the same islets detected by immunohistochemistry using antibodies against Ki67 and insulin in the same islets fixed immediately after TLVM. Similarly, we quantified the rate of β-cell apoptosis by TLVM and then the frequency of apoptosis in the same islets using TdT-mediated dUTP nick-end labeling and insulin. Conversion factors were developed by regression analysis. The conversion factor from Ki67 labeling frequency (%) to actual replication rate (%events/h) is 0.025 ± 0.003 h−1. The conversion factor from TdT-mediated dUTP nick-end labeling frequency (%) to actual apoptosis rate (%events/h) is 0.41 ± 0.05 h−1. These conversion factors will permit development of models to evaluate β-cell turnover in fixed pancreas tissue. PMID:18940937

Intraoperative Conversion From Partial to Radical Nephrectomy: Incidence, Predictive Factors, and Outcomes.

PubMed

Petros, Firas G; Keskin, Sarp K; Yu, Kai-Jie; Li, Roger; Metcalfe, Michael J; Fellman, Bryan M; Chang, Courtney M; Gu, Cindy; Tamboli, Pheroze; Matin, Surena F; Karam, Jose A; Wood, Christopher G

2018-06-01

To evaluate preoperative and intraoperative predictors of conversion to radical nephrectomy (RN) in a cohort of patients undergoing a planned partial nephrectomy (PN) for renal cell carcinoma (RCC). A single-center, retrospective review was conducted using our PN database that includes patients who were scheduled to undergo PN (regardless of the approach) but were converted to RN between August 1990 and December 2016. Reasons for conversion were collected from the operative report. Patient demographics and perioperative variables were compared with the successful PN group. Univariate and multivariate logistic regression analyses were conducted to assess predictors of conversion. A total of 1857 patients were scheduled to undergo PN. Of these patients, 90 (5%) were converted to RN. The multivariate model showed that larger tumor size (odds ratio [OR] = 1.20, P = .040), higher RENAL nephrometry score (OR = 1.41, P = .001), hilar tumor or renal sinus invasion (OR = 2.80, P = .004), laparoscopic PN (OR = 7.34, P <.001), intraoperative bleeding (OR = 19.62, P <.001), positive surgical margin (OR = 31.85, P <.001), and advanced pathologic tumor-stage (T3 or T4) (OR = 7.29, P <.001) were associated with increased odds of intraoperative conversion to RN. The rate of conversion to RN was low in patients who were scheduled to undergo PN in this series. Larger tumor size with increasing complexity, hilar tumor location or renal sinus invasion, locally advanced tumors, laparoscopic PN but not robotic PN, bleeding complication, and positive surgical margin were associated with intraoperative conversion from scheduled PN to RN. Copyright © 2018 Elsevier Inc. All rights reserved.

Does the Biosocial Model Explain the Emergence of Status Differences in Conversations among Unacquainted Men?

PubMed Central

Mazur, Allan; Welker, Keith M.; Peng, Bin

2015-01-01

Fifteen triads of unacquainted men conversed for ten minutes while stress was measured in real time by pulse rate and thumb blood volume (TBV). Salivary measures of testosterone (T), cortisol (C), and the stress-related enzyme alpha-amylase (AA) were measured at the beginning and end of the session. Fully or partially transitive status hierarchies formed in 14 triads. (Highest ranked man was scored 1, lowest 3, with ties allowed.) Ten of the triads participated in Study 1, where nothing was at stake in the casual conversation. Five additional triads were run in Study 2, intended to introduce competition by offering a $20 reward to the man afterward chosen as having led the conversation. Most results from the two studies are similar, suggesting that the $20 reward had little effect. Combining studies, pulse and TBV show that conversation is more stressful than watching a video beforehand. Within the conversation, speaking turns are more stressful than listening turns, especially among the lowest ranked men, less so among those higher in rank. This supports a stress-based mechanism for status allocation among humans. Apparently, human speech is a form of status signaling, homologous with nonlinguistic status signals used by other primates, as posited by the “biosocial model.” The biosocial model also posits that a physiological substrate (T, C, and AA) is related to dominance or status. Predicted effects are not replicated here, except for an inverse relationship between the stress enzyme AA and status. The mostly null results, obtained from conversations where there was little or nothing at stake, suggest that T and C (and their interaction) are not relevant to emergent status in the absence of serious competition. PMID:26588849

Are Victorian elective surgery cases still converting from overnight to same day cases?

PubMed

Hanning, Brian W T

2005-05-01

The conversion rate on a diagnosis related group (DRG)-standardised basis of Victorian private overnight (ON) elective surgery cases to same day (SD) cases declined from 4.7% per annum over 1996-97 to 1998-99 to 2.5% per annum over 1998-99 to 2002-03. Similar analysis within the Victorian public sector shows a decline from 3.8% per annum over 1996-97 to 1998-99 to 1.9% over 1998-99 to 2002-03. Comparison on a DRG-standardised basis shows while the public sector continued to show a higher incidence of elective surgery SD cases than the private sector in 2002-03 (by 1.6%). The difference has declined since 1998-99 when it was 2.4%. DRG-based analysis suggests the conversion rate in both sectors and the difference in SD surgery cases between the two sectors will continue to decline. Future savings in recurrent and capital cost due to ON surgery cases becoming SD cases are likely to be much lower than savings in recent years.

The carbon dioxide gasification characteristics of biomass char samples and their effect on coal gasification reactivity during co-gasification.

PubMed

Mafu, Lihle D; Neomagus, Hein W J P; Everson, Raymond C; Okolo, Gregory N; Strydom, Christien A; Bunt, John R

2018-06-01

The carbon dioxide gasification characteristics of three biomass char samples and bituminous coal char were investigated in a thermogravimetric analyser in the temperature range of 850-950 °C. Char SB exhibited higher reactivities (R i , R s , R f ) than chars SW and HW. Coal char gasification reactivities were observed to be lower than those of the three biomass chars. Correlations between the char reactivities and char characteristics were highlighted. The addition of 10% biomass had no significant impact on the coal char gasification reactivity. However, 20 and 30% biomass additions resulted in increased coal char gasification rate. During co-gasification, chars HW and SW caused increased coal char gasification reactivity at lower conversions, while char SB resulted in increased gasification rates throughout the entire conversion range. Experimental data from biomass char gasification and biomass-coal char co-gasification were well described by the MRPM, while coal char gasification was better described by the RPM. Copyright © 2018 Elsevier Ltd. All rights reserved.

Steady-state temperature distribution within a Brayton rotating unit operating in a power conversion system using helium-xenon gas

NASA Technical Reports Server (NTRS)

Johnsen, R. L.; Namkoong, D.; Edkin, R. A.

1971-01-01

The Brayton rotating unit (BRU), consisting of a turbine, an alternator, and a compressor, was tested as part of a Brayton cycle power conversion system over a side range of steady state operating conditions. The working fluid in the system was a mixture of helium-xenon gases. Turbine inlet temperature was varied from 1200 to 1600 F, compressor inlet temperature from 60 to 120 F, compressor discharge pressure from 20 to 45 psia, rotative speed from 32 400 to 39 600 rpm, and alternator liquid-coolant flow rate from 0.01 to 0.27 pound per second. Test results indicated that the BRU internal temperatures were highly sensitive to alternator coolant flow below the design value of 0.12 pound per second but much less so at higher values. The armature winding temperature was not influenced significantly by turbine inlet temperature, but was sensitive, up to 20 F per kVA alternator output, to varying alternator output. When only the rotational speed was changed (+ or - 10% of rated value), the BRU internal temperatures varied directly with the speed.

Multicenter Trial of the VenaTech Convertible Vena Cava Filter.

PubMed

Hohenwalter, Eric J; Stone, James R; O'Moore, Paul V; Smith, Steven J; Selby, J Bayne; Lewandowski, Robert J; Samuels, Shaun; Kiproff, Paul M; Trost, David W; Madoff, David C; Handel, Jeremy; Gandras, Eric J; Vlahos, Athanasios; Rilling, William S

2017-10-01

To demonstrate rates of successful filter conversion and 6-month major device-related adverse events in subjects with converted caval filters. An investigational device exemption multicenter, prospective, single-arm study was performed at 11 sites enrolling 149 patients. The VenaTech Convertible Vena Cava Filter (B. Braun Interventional Systems, Inc, Bethlehem, Pennsylvania) was implanted in 149 patients with venous thromboembolism and contraindication to or failure of anticoagulation (n = 119), with high-risk trauma (n = 14), and for surgical prophylaxis (n = 16). When the patient was no longer at risk for pulmonary embolism as determined by clinical assessment, an attempt at filter conversion was made. Follow-up of converted patients (n = 93) was conducted at 30 days, 3 months, and 6 months after conversion. Patients who did not undergo a conversion attempt (n = 53) had follow-up at 6 months after implant. All implants were successful. One 7-day migration to the right atrium required surgical removal. Technical success rate for filter conversion was 92.7% (89/96). Mean time from placement to conversion was 130.7 days (range, 15-391 d). No major conversion-related events were reported. The mean conversion procedure time was 30.7 minutes (range, 7-135 min). There were 89 converted and 32 unconverted patients who completed 6-month follow-up with no delayed complications. The VenaTech Convertible filter has a high conversion rate and low 6-month device-related adverse event rate. Further studies are necessary to determine long-term safety and efficacy in both converted and unconverted patients. Copyright © 2017 SIR. Published by Elsevier Inc. All rights reserved.

The influence of stress, depression, and anxiety on PSA screening rates in a nationally representative sample.

PubMed

Kotwal, Ashwin A; Schumm, Phil; Mohile, Supriya G; Dale, William

2012-12-01

Prostate-specific antigen (PSA) testing for prostate cancer is controversial, with concerning rates of both overscreening and underscreening. The reasons for the observed rates of screening are unknown, and few studies have examined the relationship of psychological health to PSA screening rates. Understanding this relationship can help guide interventions to improve informed decision-making for screening. A nationally representative sample of men 57-85 years old without prostate cancer (N = 1169) from the National Social life, Health and Aging Project was analyzed. The independent relationship of validated psychological health scales measuring stress, anxiety, and depression to PSA testing rates was assessed using multivariable logistic regression analyses. PSA screening rates were significantly lower for men with higher perceived stress [odds ratio (OR) = 0.76, P = 0.006], but not for higher depressive symptoms (OR = 0.89, P = 0.22) when accounting for stress. Anxiety influences PSA screening through an interaction with number of doctor visits (P = 0.02). Among the men who visited the doctor once those with higher anxiety were less likely to be screened (OR = 0.65, P = 0.04). Conversely, those who visited the doctor 10+ times with higher anxiety were more likely to be screened (OR = 1.71, P = 0.04). Perceived stress significantly lowers PSA screening likelihood, and it seems to partly mediate the negative relationship of depression with screening likelihood. Anxiety affects PSA screening rates differently for men with different numbers of doctor visits. Interventions to influence PSA screening rates should recognize the role of the patients' psychological state to improve their likelihood of making informed decisions and improve screening appropriateness.

Gravity flow rate of solids through orifices and pipes

NASA Technical Reports Server (NTRS)

Gardner, J. F.; Smith, J. E.; Hobday, J. M.

1977-01-01

Lock-hopper systems are the most common means for feeding solids to and from coal conversion reactor vessels. The rate at which crushed solids flow by gravity through the vertical pipes and valves in lock-hopper systems affects the size of pipes and valves needed to meet the solids-handling requirements of the coal conversion process. Methods used to predict flow rates are described and compared with experimental data. Preliminary indications are that solids-handling systems for coal conversion processes are over-designed by a factor of 2 or 3.

Laparoscopic anterior versus posterior fundoplication for gastro-esophageal reflux disease: a meta-analysis and systematic review.

PubMed

Memon, Muhammed Ashraf; Subramanya, Manjunath S; Hossain, Md Belal; Yunus, Rossita Mohamad; Khan, Shahjahan; Memon, Breda

2015-04-01

Although laparoscopic posterior fundoplication (LPF) i.e., Nissen or Toupet have the proven efficacy for controlling gastro-esophageal reflux surgically, there remain problems with postoperative dysphagia and gas bloat syndrome. To decrease some of these postoperative complications, laparoscopic anterior fundoplication (LAF) was introduced. The aim of this study was to conduct a meta-analysis and systematic review of randomized controlled trials (RCTs) to investigate the merits and drawbacks of LPF versus LAF for the treatment of gastro-esophageal reflux disease (GERD). A search of Medline, Embase, Science Citation Index, Current Contents, PubMed, ISI Web of Science, and the Cochrane Database identified all RCTs comparing different types of LPF and LAF published in the English Language between 1990 and 2013. The meta-analysis was prepared in accordance with the Preferred Reporting Items for Systematic reviews and Meta-analyses (PRISMA) statement. Data was extracted and analyzed on ten variables which include dysphagia score, heartburn rate, redo operative rate, operative time, overall complications, rate of conversion to open, Visick grading of satisfaction, overall satisfaction, length of hospital stay, and postoperative 24-h pH scores. Nine trials totaling 840 patients (anterior = 425, posterior = 415) were analyzed. There was a significant reduction in the odds ratio for dysphagia in the LAF group compared to the LPF group. Conversely, significant reduction in the odds ratio for heartburn was observed for LPF compared to LAF. Comparable effects were noted for both groups for other variables which include redo surgery, operating time, overall complications, conversion rate, Visick's grading, patients' satisfaction, length of hospital stay, and postoperative 24-h pH scores. Based on this meta-analysis, LPF compared to LAF is associated with significant reduction in heartburn at the expense of higher dysphagia rate on a short- and medium-term basis. We therefore conclude that LPF is a better alternative to LAF for controlling GERD symptoms.

Impact of HFIR LEU Conversion on Beryllium Reflector Degradation Factors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ilas, Dan

2013-10-01

An assessment of the impact of low enriched uranium (LEU) conversion on the factors that may cause the degradation of the beryllium reflector is performed for the High Flux Isotope Reactor (HFIR). The computational methods, models, and tools, comparisons with previous work, along with the results obtained are documented and discussed in this report. The report documents the results for the gas and neutronic poison production, and the heating in the beryllium reflector for both the highly enriched uranium (HEU) and LEU HFIR configurations, and discusses the impact that the conversion to LEU may have on these quantities. A time-averagingmore » procedure was developed to calculate the isotopic (gas and poisons) production in reflector. The sensitivity of this approach to different approximations is gauged and documented. The results show that the gas is produced in the beryllium reflector at a total rate of 0.304 g/cycle for the HEU configuration; this rate increases by ~12% for the LEU case. The total tritium production rate in reflector is 0.098 g/cycle for the HEU core and approximately 11% higher for the LEU core. A significant increase (up to ~25%) in the neutronic poisons production in the reflector during the operation cycles is observed for the LEU core, compared to the HEU case, for regions close to the core s horizontal midplane. The poisoning level of the reflector may increase by more than two orders of magnitude during long periods of downtime. The heating rate in the reflector is estimated to be approximately 20% lower for the LEU core than for the HEU core. The decrease is due to a significantly lower contribution of the heating produced by the gamma radiation for the LEU core. Both the isotopic (gas and neutronic poisons) production and the heating rates are spatially non-uniform throughout the beryllium reflector volume. The maximum values typically occur in the removable reflector and close to the midplane.« less

Simultaneous wavelength conversion of ASK and DPSK signals based on four-wave-mixing in dispersion engineered silicon waveguides.

PubMed

Xu, Lin; Ophir, Noam; Menard, Michael; Lau, Ryan Kin Wah; Turner-Foster, Amy C; Foster, Mark A; Lipson, Michal; Gaeta, Alexander L; Bergman, Keren

2011-06-20

We experimentally demonstrate four-wave-mixing (FWM)-based continuous wavelength conversion of optical differential-phase-shift-keyed (DPSK) signals with large wavelength conversion ranges as well as simultaneous wavelength conversion of dual-wavelength channels with mixed modulation formats in 1.1-cm-long dispersion-engineered silicon waveguides. We first validate up to 100-nm wavelength conversion range for 10-Gb/s DPSK signals, showcasing the capability to perform phase-preserving operations at high bit rates in chip-scale devices over wide conversion ranges. We further validate the wavelength conversion of dual-wavelength channels modulated with 10-Gb/s packetized phase-shift-keyed (PSK) and amplitude-shift-keyed (ASK) signals; demonstrate simultaneous operation on multiple channels with mixed formats in chip-scale devices. For both configurations, we measure the spectral and temporal responses and evaluate the performances using bit-error-rate (BER) measurements.

The rate of meiotic gene conversion varies by sex and age

PubMed Central

Halldorsson, Bjarni V.; Hardarson, Marteinn T.; Kehr, Birte; Styrkarsdottir, Unnur; Gylfason, Arnaldur; Thorleifsson, Gudmar; Zink, Florian; Jonasdottir, Adalbjorg; Jonasdottir, Aslaug; Sulem, Patrick; Masson, Gisli; Thorsteinsdottir, Unnur; Helgason, Agnar; Kong, Augustine; Gudbjartsson, Daniel F.; Stefansson, Kari

2016-01-01

Meiotic recombination involves a combination of gene conversion and crossover events that along with mutations produce germline genetic diversity. Here, we report the discovery of 3,176 SNP and 61 indel gene conversions. Our estimate of the non-crossover (NCO) gene conversion rate (G) is 7.0 for SNPs and 5.8 for indels per Mb per generation, and the GC bias is 67.6%. For indels we demonstrate a 65.6% preference for the shorter allele. NCO gene conversions from mothers are longer than those from fathers and G is 2.17 times greater in mothers. Notably, G increases with the age of mothers, but not fathers. A disproportionate number of NCO gene conversions in older mothers occur outside double strand break (DSB) regions and in regions with relatively low GC content. This points to age-related changes in the mechanisms of meiotic gene conversions in oocytes. PMID:27643539

Carbon translocation from symbiont to host depends on irradiance and food availability in the tropical coral Stylophora pistillata

NASA Astrophysics Data System (ADS)

Tremblay, P.; Grover, R.; Maguer, J. F.; Hoogenboom, M.; Ferrier-Pagès, C.

2014-03-01

Reef-building corals live in symbiosis with dinoflagellates that translocate a large proportion of their photosynthetically fixed carbon compounds to their coral host for its own metabolism. The carbon budget and translocation rate, however, vary depending on environmental conditions, coral host species, and symbiont clade. To quantify variability in carbon translocation in response to environmental conditions, this study assessed the effect of two different irradiance levels (120 and 250 μmol photons m-2 s-1) and feeding regimes (fed with Artemia salina nauplii and unfed) on the carbon budget of the tropical coral Stylophora pistillata. For this purpose, H13CO3 --enriched seawater was used to trace the conversion of photosynthetic carbon into symbiont and coral biomass and excrete particulate organic carbon. Results showed that carbon translocation (ca. 78 %) and utilization were similar under both irradiance levels for unfed colonies. In contrast, carbon utilization by fed colonies was dependent on the growth irradiance. Under low irradiance, heterotrophy was accompanied by lower carbon translocation (71 %), higher host and symbiont biomass, and higher calcification rates. Under high irradiance, heterotrophy was accompanied by higher rates of photosynthesis, respiration, and carbon translocation (90 %) as well as higher host biomass. Hence, levels of resource sharing within coral-dinoflagellate symbioses depend critically on environmental conditions.

Can quantum coherent solar cells break detailed balance?

NASA Astrophysics Data System (ADS)

Kirk, Alexander P.

2015-07-01

Carefully engineered coherent quantum states have been proposed as a design attribute that is hypothesized to enable solar photovoltaic cells to break the detailed balance (or radiative) limit of power conversion efficiency by possibly causing radiative recombination to be suppressed. However, in full compliance with the principles of statistical mechanics and the laws of thermodynamics, specially prepared coherent quantum states do not allow a solar photovoltaic cell—a quantum threshold energy conversion device—to exceed the detailed balance limit of power conversion efficiency. At the condition given by steady-state open circuit operation with zero nonradiative recombination, the photon absorption rate (or carrier photogeneration rate) must balance the photon emission rate (or carrier radiative recombination rate) thus ensuring that detailed balance prevails. Quantum state transitions, entropy-generating hot carrier relaxation, and photon absorption and emission rate balancing are employed holistically and self-consistently along with calculations of current density, voltage, and power conversion efficiency to explain why detailed balance may not be violated in solar photovoltaic cells.

Kinetics and mechanism of the oxidation of S(IV) by ozone in aqueous solution with particular reference to SO2 conversion in nonurban tropospheric clouds

NASA Technical Reports Server (NTRS)

Maahs, H. G.

1983-01-01

Results are presented from a laboratory study of the kinetics of the S(IV)-O3 reaction in aqueous solution, including measurements of the effects of UV radiation, dissolved transition metals, and an antioxidant (hydroquinone) on the rate. On the basis of the results, relative rates of S(IV) conversion by O3 in tropospheric cloud water are compared with those predicted for H2O2 and for O2. The reaction mechanism is discussed, with an outline given of the elements of a possible reaction scheme. Application of the rate constants obtained to SO2 conversion in cloud water predicts conversion rates by ozone to be competitive with those by H2O2 at pH above about 4.5 and to dominate at pH above about 5.5. It is pointed out that since these pH's are typical for nonurban tropospheric cloud water, ozone is a potentially important contributor to the overall oxidative conversion of SO2 to sulfate in the nonurban troposphere.

Pressurized chemical-looping combustion of coal with an iron ore-based oxygen carrier

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xiao, Rui; Song, Min; Zhang, Shuai

2010-06-15

Chemical-looping combustion (CLC) is a new combustion technology with inherent separation of CO{sub 2}. Most of the previous investigations on CLC of solid fuels were conducted under atmospheric pressure. A pressurized CLC combined cycle (PCLC-CC) system is proposed as a promising coal combustion technology with potential higher system efficiency, higher fuel conversion, and lower cost for CO{sub 2} sequestration. In this study pressurized CLC of coal with Companhia Valedo Rio Doce (CVRD) iron ore was investigated in a laboratory fixed bed reactor. CVRD iron ore particles were exposed alternately to reduction by 0.4 g of Chinese Xuzhou bituminous coal gasifiedmore » with 87.2% steam/N{sub 2} mixture and oxidation with 5% O{sub 2} in N{sub 2} at 970 C. The operating pressure was varied between 0.1 MPa and 0.6 MPa. First, control experiments of steam coal gasification over quartz sand were performed. H{sub 2} and CO{sub 2} are the major components of the gasification products, and the operating pressure influences the gas composition. Higher concentrations of CO{sub 2} and lower fractions of CO, CH{sub 4}, and H{sub 2} during the reduction process with CVRD iron ore was achieved under higher pressures. The effects of pressure on the coal gasification rate in the presence of the oxygen carrier were different for pyrolysis and char gasification. The pressurized condition suppresses the initial coal pyrolysis process while it also enhances coal char gasification and reduction with iron ore in steam, and thus improves the overall reaction rate of CLC. The oxidation rates and variation of oxygen carrier conversion are higher at elevated pressures reflecting higher reduction level in the previous reduction period. Scanning electron microscope and energy-dispersive X-ray spectroscopy (SEM-EDX) analyses show that particles become porous after experiments but maintain structure and size after several cycles. Agglomeration was not observed in this study. An EDX analysis demonstrates that there is very little coal ash deposited on the oxygen carrier particles but no appreciable crystalline phases change as verified by X-ray diffraction (XRD) analysis. Overall, the limited pressurized CLC experiments carried out in the present work suggest that PCLC of coal is promising and further investigations are necessary. (author)« less

Characterizing the subjective experience of episodic past, future, and counterfactual thinking in healthy younger and older adults.

PubMed

De Brigard, Felipe; Giovanello, Kelly S; Stewart, Gregory W; Lockrow, Amber W; O'Brien, Margaret M; Spreng, R Nathan

2016-12-01

Recent evidence demonstrates remarkable overlap in the neural and cognitive mechanisms underlying episodic memory, episodic future thinking, and episodic counterfactual thinking. However, the extent to which the phenomenological characteristics associated with these mental simulations change as a result of ageing remains largely unexplored. The current study employs adapted versions of the Memory Characteristics Questionnaire and the Autobiographical Interview to compare the phenomenological characteristics associated with both positive and negative episodic past, future, and counterfactual simulations in younger and older adults. Additionally, it explores the influence of perceived likelihood in the experience of such simulations. The results indicate that, across all simulations, older adults generate more external details and report higher ratings of vividness, composition, and intensity than young adults. Conversely, younger adults generate more internal details across all conditions and rated positive and negative likely future events as more likely than did older adults. Additionally, both younger and older adults reported higher ratings for sensory, composition, and intensity factors during episodic memories relative to future and counterfactual thoughts. Finally, for both groups, ratings of spatial coherence and composition were higher for likely counterfactuals than for both unlikely counterfactuals and future simulations. Implications for the psychology of mental simulation and ageing are discussed.

Treatment of corn ethanol distillery wastewater using two-stage anaerobic digestion.

PubMed

Ráduly, B; Gyenge, L; Szilveszter, Sz; Kedves, A; Crognale, S

In this study the mesophilic two-stage anaerobic digestion (AD) of corn bioethanol distillery wastewater is investigated in laboratory-scale reactors. Two-stage AD technology separates the different sub-processes of the AD in two distinct reactors, enabling the use of optimal conditions for the different microbial consortia involved in the different process phases, and thus allowing for higher applicable organic loading rates (OLRs), shorter hydraulic retention times (HRTs) and better conversion rates of the organic matter, as well as higher methane content of the produced biogas. In our experiments the reactors have been operated in semi-continuous phase-separated mode. A specific methane production of 1,092 mL/(L·d) has been reached at an OLR of 6.5 g TCOD/(L·d) (TCOD: total chemical oxygen demand) and a total HRT of 21 days (5.7 days in the first-stage, and 15.3 days in the second-stage reactor). Nonetheless the methane concentration in the second-stage reactor was very high (78.9%); the two-stage AD outperformed the reference single-stage AD (conducted at the same reactor loading rate and retention time) by only a small margin in terms of volumetric methane production rate. This makes questionable whether the higher methane content of the biogas counterbalances the added complexity of the two-stage digestion.

Ultrasound assisted lipase catalyzed synthesis of poly-6-hydroxyhexanoate.

PubMed

Gumel, A M; Annuar, M S M; Chisti, Y; Heidelberg, T

2012-05-01

Ultrasonic irradiation greatly improved the Candida antarctica lipase B mediated ring opening polymerization of ε-caprolactone to poly-6-hydroxyhexanoate in the ionic liquid 1-ethyl-3-methylimidazolium tetraflouroborate. Compared to the conventional nonsonicated reaction, sonication improved the monomer conversion by 63% and afforded a polymer product of a narrower molecular weight distribution and a higher degree of crystallinity. Under sonication, the polydispersity index of the product was ~1.44 compared to a value of ~2.55 for the product of the conventional reaction. With sonication, nearly 75% of the monomer was converted to product, but the conversion was only ~16% for the reaction carried out conventionally. Compared to conventional operation, sonication enhanced the rate of polymer propagation by >2-fold and the turnover number of the lipase by >3-fold. Copyright © 2011 Elsevier B.V. All rights reserved.

Isomerization of n-hexane and n-pentane mixture on Pt-alumina catalyst

DOE Office of Scientific and Technical Information (OSTI.GOV)

Radhi, M.A.; Al-Mutawalli, F.S.; Al-Sammarie, E.A.

A mixture of n-hexane and n-penane (1:1) by volume was isomerized on commercial Pt-alumina catalyst in a continuously fixed-bed reactor at atmospheric pressure. The effect of temperature, LHSV, hydrogen/hyrocarbon molar ratio and chlorine concentration were studied. It was found that the yield of isohexanes and isopentane increases with increasing the chloride added up to 0.1 and 0.2 mole % CCl/sub 4/ respectively. The rate of isomerization became slower at higher concentrations. Isomerization activity of the catalyst increases with increasing temperature ranging between 350-400/sup 0/C. The yield of isomers decrease with increasing temperature above 400/sup 0/C. The relative conversion of n-hexanemore » in the mixture was found to be more than the conversion of pure n-hexane at the same conditions.« less

Intermittent fasting induces hypothalamic modifications resulting in low feeding efficiency, low body mass and overeating.

PubMed

Chausse, Bruno; Solon, Carina; Caldeira da Silva, Camille C; Masselli Dos Reis, Ivan G; Manchado-Gobatto, Fúlvia B; Gobatto, Claudio A; Velloso, Licio A; Kowaltowski, Alicia J

2014-07-01

Intermittent fasting (IF) is an often-used intervention to decrease body mass. In male Sprague-Dawley rats, 24 hour cycles of IF result in light caloric restriction, reduced body mass gain, and significant decreases in the efficiency of energy conversion. Here, we study the metabolic effects of IF in order to uncover mechanisms involved in this lower energy conversion efficiency. After 3 weeks, IF animals displayed overeating during fed periods and lower body mass, accompanied by alterations in energy-related tissue mass. The lower efficiency of energy use was not due to uncoupling of muscle mitochondria. Enhanced lipid oxidation was observed during fasting days, whereas fed days were accompanied by higher metabolic rates. Furthermore, an increased expression of orexigenic neurotransmitters AGRP and NPY in the hypothalamus of IF animals was found, even on feeding days, which could explain the overeating pattern. Together, these effects provide a mechanistic explanation for the lower efficiency of energy conversion observed. Overall, we find that IF promotes changes in hypothalamic function that explain differences in body mass and caloric intake.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yuan Zhang; Jin-hu Wu; Dong-ke Zhang

The cracking of oil refinery off-gas, simulated with a gas mixture containing methane (51%), ethylene (21.4%), ethane (21.1%), and propane (6.5%), over a coal char, petroleum coke, and quartz, respectively, has been studied in a fixed bed reactor. The experiments were performed at temperatures between 850 and 1000{sup o}C and at atmospheric pressure. The results show that the conversions of all species considered increased with increasing temperature. Ethane and propane completely decomposed over all three bed materials in the temperature range investigated. However, the higher initial conversion rates of methane and ethylene cracking at all temperatures were observed only overmore » the coal char and not on the petroleum coke and quartz, indicating a significant catalytic effect of the coal char on methane and ethylene cracking. Methane and ethylene conversions decreased with reaction time due to deactivation of the coal char by carbon deposition on the char surface and, in the later stage of a cracking experiment, became negative, suggesting that methane and ethylene had been formed during the cracking of ethane and propane. 16 refs., 13 figs., 2 tabs.« less

Si-rich SiNx based Kerr switch enables optical data conversion up to 12 Gbit/s

PubMed Central

Lin, Gong-Ru; Su, Sheng-Pin; Wu, Chung-Lun; Lin, Yung-Hsiang; Huang, Bo-Ji; Wang, Huai-Yung; Tsai, Cheng-Ting; Wu, Chih-I; Chi, Yu-Chieh

2015-01-01

Silicon photonic interconnection on chip is the emerging issue for next-generation integrated circuits. With the Si-rich SiNx micro-ring based optical Kerr switch, we demonstrate for the first time the wavelength and format conversion of optical on-off-keying data with a bit-rate of 12 Gbit/s. The field-resonant nonlinear Kerr effect enhances the transient refractive index change when coupling the optical data-stream into the micro-ring through the bus waveguide. This effectively red-shifts the notched dip wavelength to cause the format preserved or inversed conversion of data carried by the on-resonant or off-resonant probe, respectively. The Si quantum dots doped Si-rich SiNx strengthens its nonlinear Kerr coefficient by two-orders of magnitude higher than that of bulk Si or Si3N4. The wavelength-converted and cross-amplitude-modulated probe data-stream at up to 12-Gbit/s through the Si-rich SiNx micro-ring with penalty of −7 dB on transmission has shown very promising applicability to all-optical communication networks. PMID:25923653

Si-rich SiNx based Kerr switch enables optical data conversion up to 12 Gbit/s.

PubMed

Lin, Gong-Ru; Su, Sheng-Pin; Wu, Chung-Lun; Lin, Yung-Hsiang; Huang, Bo-Ji; Wang, Huai-Yung; Tsai, Cheng-Ting; Wu, Chih-I; Chi, Yu-Chieh

2015-04-29

Silicon photonic interconnection on chip is the emerging issue for next-generation integrated circuits. With the Si-rich SiNx micro-ring based optical Kerr switch, we demonstrate for the first time the wavelength and format conversion of optical on-off-keying data with a bit-rate of 12 Gbit/s. The field-resonant nonlinear Kerr effect enhances the transient refractive index change when coupling the optical data-stream into the micro-ring through the bus waveguide. This effectively red-shifts the notched dip wavelength to cause the format preserved or inversed conversion of data carried by the on-resonant or off-resonant probe, respectively. The Si quantum dots doped Si-rich SiNx strengthens its nonlinear Kerr coefficient by two-orders of magnitude higher than that of bulk Si or Si3N4. The wavelength-converted and cross-amplitude-modulated probe data-stream at up to 12-Gbit/s through the Si-rich SiNx micro-ring with penalty of -7 dB on transmission has shown very promising applicability to all-optical communication networks.

Catalytic conversion of biomass-derived ethanol to liquid hydrocarbon blend-stock: Effect of light gas recirculation

DOE PAGES

Li, Zhenglong; Lepore, Andrew W.; Davison, Brian H.; ...

2016-01-01

Here, we describe a light gas recirculation (LGR) method to increase the liquid hydrocarbon yield with reduced aromatic content from catalytic conversion of ethanol to hydrocarbons. The previous liquid hydrocarbon yield is ~40% from one-pass ethanol conversion over V-ZSM-5 at 350 C and atmospheric pressure where the remaining ~60% yield is light gas hydrocarbons. In comparison, the liquid hydrocarbon yield increases to 80% when a simulated light gas hydrocarbon stream is co-fed at a rate of 0.053 mol g-1 h-1 with ethanol due to the conversion of most of the light olefins. The LGR also significantly improves the quality ofmore » the liquid hydrocarbon blend-stock by reducing aromatic content and overall benzene concentration. For 0.027 mol g-1 h-1 light gas mixture co-feeding, the average aromatic content in liquid hydrocarbons is 51.5% compared with 62.5% aromatic content in ethanol only experiment. Average benzene concentration decreases from 3.75% to 1.5% which is highly desirable since EPA limits benzene concentration in gasoline to 0.62%. As a result of low benzene concentration, the blend-wall for ethanol derived liquid hydrocarbons changes from ~18% to 43%. The remaining light paraffins and olefins can be further converted to valuable BTX products (94% BTX in the liquid) over Ga-ZSM-5 at 500 C. Thus, the LGR is an effective approach to convert ethanol to liquid hydrocarbons with higher liquid yield and low aromatic content, especially low benzene concentration, which could be blended with gasoline in a much higher ratio than ethanol or ethanol derived hydrocarbon blend-stock.« less

Catalytic conversion of biomass-derived ethanol to liquid hydrocarbon blend-stock: Effect of light gas recirculation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Zhenglong; Lepore, Andrew W.; Davison, Brian H.

Here, we describe a light gas recirculation (LGR) method to increase the liquid hydrocarbon yield with reduced aromatic content from catalytic conversion of ethanol to hydrocarbons. The previous liquid hydrocarbon yield is ~40% from one-pass ethanol conversion over V-ZSM-5 at 350 C and atmospheric pressure where the remaining ~60% yield is light gas hydrocarbons. In comparison, the liquid hydrocarbon yield increases to 80% when a simulated light gas hydrocarbon stream is co-fed at a rate of 0.053 mol g-1 h-1 with ethanol due to the conversion of most of the light olefins. The LGR also significantly improves the quality ofmore » the liquid hydrocarbon blend-stock by reducing aromatic content and overall benzene concentration. For 0.027 mol g-1 h-1 light gas mixture co-feeding, the average aromatic content in liquid hydrocarbons is 51.5% compared with 62.5% aromatic content in ethanol only experiment. Average benzene concentration decreases from 3.75% to 1.5% which is highly desirable since EPA limits benzene concentration in gasoline to 0.62%. As a result of low benzene concentration, the blend-wall for ethanol derived liquid hydrocarbons changes from ~18% to 43%. The remaining light paraffins and olefins can be further converted to valuable BTX products (94% BTX in the liquid) over Ga-ZSM-5 at 500 C. Thus, the LGR is an effective approach to convert ethanol to liquid hydrocarbons with higher liquid yield and low aromatic content, especially low benzene concentration, which could be blended with gasoline in a much higher ratio than ethanol or ethanol derived hydrocarbon blend-stock.« less

Mississippi Basin Carbon Project; upland soil database for sites in Yazoo Basin, northern Mississippi

USGS Publications Warehouse

Harden, J.W.; Fries, T.L.; Huntington, T.G.

1999-01-01

The conversion of land from its native state to an agricultural use commonly results in a significant loss of soil carbon (Mann, 1985; Davidson and Ackerman, 1993). Globally, this loss is estimated to account for as much as 1/3 of the net CO2 emissions for the period of 1850 to 1980 (Houghton et al, 1983). Roughly 20 to 40 percent of original soil carbon is estimated to be lost as CO2 as a result of agricultural conversion, or 'decomposition enhancement', and global models use this estimate along with land conversion data to provide agricultural contributions of CO2 emissions for global carbon budgets (Houghton and others, 1983; Schimel, 1995). As yet, erosional losses of carbon are not included in global carbon budgets explicitly as a factor in land conversion nor implicitly as a portion of the decomposition enhancement. However, recent work by Lal et al (1995) and by Stallard (1998) suggests that significant amounts of eroded soil may be stored in man-made reservoirs and depositional environments as a result of agricultural conversion. Moreover, Stallard points out that if eroding soils have the potential for replacing part of the carbon trapped in man-made reservoirs, then the global carbon budget may grossly underestimate or ignore a significant sink term resulting from the burial of eroded soil. Soil erosion rates are significantly (10X) higher on croplands than on their undisturbed equivalents (Dabney et al, 1997). Most of the concern over erosion is related to diminished productivity of the uplands (Stallings, 1957; McGregor et al, 1993; Rhoton and Tyler, 1990) or to increased hazards and navigability of the lowlands in the late 1800's to early 1900's. Yet because soil carbon is concentrated at the soil surface, with an exponential decline in concentration with depth, it is clear that changes in erosion rates seen on croplands must also impact soil carbon storage and terrestrial carbon budgets as well.

Mississippi Basin Carbon Project: upland soil database for sites in Nishnabotna River basin, Iowa

USGS Publications Warehouse

Harden, J.W.; Fries, T.L.; Haughy, R.; Kramer, L.; Zheng, Shuhui

2001-01-01

The conversion of land from its native state to an agricultural use commonly results in a significant loss of soil carbon (Mann, 1985; Davidson and Ackerman, 1993). Globally, this loss is estimated to account for as much as 1/3 of the net CO2 emissions for the period of 1850 to 1980 (Houghton and others, 1983). Roughly 20 to 40 percent of original soil carbon is estimated to be lost as CO2 as a result of agricultural conversion, or "decomposition enhancement". Global models use this estimate along with land conversion data to provide agricultural contributions of CO2 emissions for global carbon budgets (Houghton and others, 1983; Schimel, 1995). Soil erosion rates are significantly (10X) higher on croplands than on their undisturbed equivalents (Dabney and others, 1997). Most of the concern over erosion is related to diminished productivity of the uplands (Stallings, 1957; McGregor and others, 1969; Rhoton, 1990) or to increased hazards and navigability of the lowlands in the late 1800's to early 1900's. Yet because soil carbon is concentrated at the soil surface, with an exponential decline in concentration with depth (Harden et al, 1999), it is clear that changes in erosion rates seen on croplands must also impact soil carbon storage and terrestrial carbon budgets as well. As yet, erosional losses of carbon are not included in global carbon budgets explicitly as a factor in land conversion nor implicitly as a portion of the decomposition enhancement. However, recent work by Lal and others (1995) and by Stallard (1998) suggests that significant amounts of eroded soil may be stored in man-made reservoirs and depositional environments as a result of agricultural conversion. Moreover, Stallard points out that eroding soils have the potential for replacing part of the carbon trapped in man-made reservoirs. If true, then the global carbon budget may grossly underestimate or ignore a significant sink term resulting from the burial of eroded soil.

Differential Rate of Deforestation in Two Adjoining Indian River Basins: Does Resource Availability Matters?

NASA Astrophysics Data System (ADS)

Das, P.; Behera, M. D.

2017-12-01

Deforestation is one of the key factors of global climate change by altering the surface albedo reduces the evapotranspiration and surface roughness leads to warming in tropical regions. River basins are always subjected to LULC changes, especially decline in forest cover to give way for agricultural expansion, urbanisation, industrialisation etc. We generated LULC maps at three decadal intervals i.e., 1985, 1995 and 2005 in two major river basins of India using Landsat data employing on-screen visual image interpretation technique. In Rain-fed, Mahanadi river basin (MRB), 30.64% forest cover in 1985 was reduced to 30.13% in 2005, wherein glacier-fed, Brahmaputra river basin (BRB) this change was 63.44% to 62.32% during 1985 to 2005. Though conversion of forest land for agricultural activities was the major LULC changes in both the basins, the rate was more than two times higher in BRB than MRB. Scrub land in few zones acted as an intermediate class for mixed forest conversion to cropland land in both the basins. Analysing the drivers, in deforestation we observed the proximity zones around habitat and socio-economic drivers contributed higher compared to topographic, edaphic and climate. Using Dyna-CLUE modelling approach, we have predicted the LULC for 2025. For validation, comparing the predicted result with actual LULC of 2005, we obtained > 97% modeling accuracy; therefore it is expected that the Dyna-CLUE model has very well predicted the LULC for the year 2025. The predicted LULC of 2025 captured the similar trend of deforestation around 0.52% in MRB and 1.18% in BRB during 2005 to 2025. Acting as early warning, and with the past 2-decadal change analysis this study is believed to help the land use planners for improved regional planning to create balanced ecosystem, especially in a changing climate. On the basis of driver analysis, we believe that availability of more forest resources in Brahmaputra River basin provided extra liberty for higher deforestation for agriculture land conversion, followed by other developmental activities in comparison to Mahanadi River basin.

Au@TiO2 yolk-shell nanostructures for enhanced performance in both photoelectric and photocatalytic solar conversion

NASA Astrophysics Data System (ADS)

He, Qinrong; Sun, Hang; Shang, Yinxing; Tang, Yanan; She, Ping; Zeng, Shan; Xu, Kongliang; Lu, Guolong; Liang, Song; Yin, Shengyan; Liu, Zhenning

2018-05-01

Solar energy conversion is an important field gaining increasing interest. Herein, bio-inspired Au@TiO2 yolk-shell nanoparticles (NPs) have been prepared via a facial one-pot hydrothermal approach. The Au@TiO2 yolk-shell NPs can self-assemble into 3D-structure to form photoelectrode for photoelectric conversion. The obtained photoelectrode demonstrates a swift and stable photocurrent of 3.5 μA/cm2, which is 4.2 and 1.6 times higher than those of the photocurrents generated by the counterparts of commercial TiO2 and Au@TiO2 core-shell NPs, respectively. Moreover, compared to the commercial TiO2 and Au@TiO2 core-shell NPs, the Au@TiO2 yolk-shell NPs also exhibit superior photocatalytic activity, delivering a H2 evolution rate of 4.92 mmol/g h. The performance improvement observed for the Au@TiO2 yolk-shell NPs is likely contributed by two synergistic factors, i.e. the incorporation of AuNPs and the unique hollow structure, which benefit the activity by simultaneously enhancing light utilization, charge separation and reaction site accessibility. The rational design and fabrication of Au@TiO2 yolk-shell NPs hold great promise for future application in efficient solar energy conversion.

Local Structure Evolution and Modes of Charge Storage in Secondary Li–FeS 2 Cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Butala, Megan M.; Mayo, Martin; Doan-Nguyen, Vicky V. T.

2017-03-27

In the pursuit of high-capacity electrochemical energy storage, a promising domain of research involves conversion reaction schemes, wherein electrode materials are fully transformed during charge and discharge. There are, however, numerous difficulties in realizing theoretical capacity and high rate capability in many conversion schemes. Here we employ operando studies to understand the conversion material FeS2, focusing on the local structure evolution of this relatively reversible material. X-ray absorption spectroscopy, pair distribution function analysis, and first-principles calculations of intermediate structures shed light on the mechanism of charge storage in the Li-FeS2 system, with some general principles emerging for charge storage inmore » chalcogenide materials. Focusing on second and later charge/discharge cycles, we find small, disordered domains that locally resemble Fe and Li2S at the end of the first discharge. Upon charge, this is converted to a Li-Fe-S composition whose local structure reveals tetrahedrally coordinated Fe. With continued charge, this ternary composition displays insertion extraction behavior at higher potentials and lower Li content. The finding of hybrid modes of charge storage, rather than simple conversion, points to the important role of intermediates that appear to store charge by mechanisms that more closely resemble intercalation.« less

In Vitro vs In Silico Detected SNPs for the Development of a Genotyping Array: What Can We Learn from a Non-Model Species?

PubMed Central

Lepoittevin, Camille; Frigerio, Jean-Marc; Garnier-Géré, Pauline; Salin, Franck; Cervera, María-Teresa; Vornam, Barbara; Harvengt, Luc; Plomion, Christophe

2010-01-01

Background There is considerable interest in the high-throughput discovery and genotyping of single nucleotide polymorphisms (SNPs) to accelerate genetic mapping and enable association studies. This study provides an assessment of EST-derived and resequencing-derived SNP quality in maritime pine (Pinus pinaster Ait.), a conifer characterized by a huge genome size (∼23.8 Gb/C). Methodology/Principal Findings A 384-SNPs GoldenGate genotyping array was built from i/ 184 SNPs originally detected in a set of 40 re-sequenced candidate genes (in vitro SNPs), chosen on the basis of functionality scores, presence of neighboring polymorphisms, minor allele frequencies and linkage disequilibrium and ii/ 200 SNPs screened from ESTs (in silico SNPs) selected based on the number of ESTs used for SNP detection, the SNP minor allele frequency and the quality of SNP flanking sequences. The global success rate of the assay was 66.9%, and a conversion rate (considering only polymorphic SNPs) of 51% was achieved. In vitro SNPs showed significantly higher genotyping-success and conversion rates than in silico SNPs (+11.5% and +18.5%, respectively). The reproducibility was 100%, and the genotyping error rate very low (0.54%, dropping down to 0.06% when removing four SNPs showing elevated error rates). Conclusions/Significance This study demonstrates that ESTs provide a resource for SNP identification in non-model species, which do not require any additional bench work and little bio-informatics analysis. However, the time and cost benefits of in silico SNPs are counterbalanced by a lower conversion rate than in vitro SNPs. This drawback is acceptable for population-based experiments, but could be dramatic in experiments involving samples from narrow genetic backgrounds. In addition, we showed that both the visual inspection of genotyping clusters and the estimation of a per SNP error rate should help identify markers that are not suitable to the GoldenGate technology in species characterized by a large and complex genome. PMID:20543950

Empirical evaluation of inhibitory product, substrate, and enzyme effects during the enzymatic saccharification of lignocellulosic biomass.

PubMed

Smith, Benjamin T; Knutsen, Jeffrey S; Davis, Robert H

2010-05-01

The cellulose hydrolysis kinetics during batch enzymatic saccharification are typified by a rapid initial rate that subsequently decays, resulting in incomplete conversion. Previous studies suggest that changes associated with the solution, substrate, or enzymes may be responsible. In this work, kinetic experiments were conducted to determine the relative magnitude of these effects. Pretreated corn stover (PCS) was used as a lignocellulosic substrate likely to be found in a commercial saccharification process, while Avicel and Kraft lignin were used to create model substrates. Glucose inhibition was observed by spiking the reaction slurry with glucose during initial-rate experiments. Increasing the glucose concentration from 7 to 48 g/L reduced the cellulose conversion rate by 94%. When product sugars were removed using ultrafiltration with a 10 kDa membrane, the glucose-based conversion increased by 9.5%. Reductions in substrate reactivity with conversion were compared directly by saccharifying PCS and Avicel substrates that had been pre-reacted to different conversions. Reaction of substrate with a pre-conversion of 40% resulted in about 40% reduction in the initial rate of saccharification, relative to fresh substrate with identical cellulose concentration. Overall, glucose inhibition and reduced substrate reactivity appear to be dominant factors, whereas minimal reductions of enzyme activity were observed.

Clean synthesis of biolubricant range esters using novel liquid lipase enzyme in solvent free medium.

PubMed

Trivedi, Jayati; Aila, Mounika; Sharma, Chandra Dutt; Gupta, Piyush; Kaul, Savita

2015-01-01

In view of the rising global problems of environment pollution and degradation, the present process provides a 'green solution' to the synthesis of higher esters of lubricant range, more specifically in the range C12-C36, using different combinations of acids and alcohols, in a single step reaction. The esters produced are biodegradable in nature and have a plethora of uses, such as in additives, as lubricating oils and other hydraulic fluids. The enzymatic esterification was performed using liquid (non-immobilized or free) lipase enzyme, without any additional organic solvent. Soluble lipase proves to be superior to immobilized enzymes as it is more cost effective and provides a faster process for the production of higher esters of lubricant range. An interesting finding was, that the lipase enzyme showed higher conversion rates with increasing carbon number of straight chain alcohols and acids. Reactions were carried out for the optimization of initial water concentration, temperature, pH of the substrate mixture and the chain length of the substrates. Under optimized conditions, the method was suitable to achieve ~ 99% conversion. Thus, the process provides an environment friendly, enzymatic alternative to the chemical route which is currently used in the industrial synthesis of lubricant components.

Deliberate modification of the solid electrolyte interphase (SEI) during lithiation of magnetite, Fe 3O 4: impact on electrochemistry

DOE PAGES

Bock, David C.; Marschilok, Amy C.; Takeuchi, Kenneth J.; ...

2017-11-20

Here, magnetite is a conversion anode material displaying multi-electron transfer during lithiation and delithiation. The solid electrolyte interphase (SEI) on magnetite, Fe 3O 4, electrodes for lithium ion batteries was deliberately modified through the use of fluoroethylene carbonate (FEC) electrolyte additive, improving both capacity retention and rate capability. Analysis showed reduction of FEC at higher voltage compared to non-fluorinated solvents with formation of a modified lithium flouride containing electrode surface.

What Drives Apostates and Converters? The Social and Familial Antecedents of Religious Change among Adolescents

PubMed Central

Longo, Gregory S.; Kim-Spoon, Jungmeen

2015-01-01

While research on the psychology of religion and spirituality has examined religious conversion, little research has examined social and familial variables that might play a role in conversion in adolescence. Longitudinal work examining concurrent conversion experiences – as opposed to retrospective reports – is particularly rare. In an examination of 209 parent-adolescent dyads, findings suggested that those who became religious at Time 2 had higher social competence at Time 1 than did apostates, whereas adolescents who were religious at both times had higher social competence, parent communication, and parent trust than apostates. Additionally, those who converted to their parent’s religion at Time 2 were higher than apostates in Time 1 social competence and parent communication. Results point to the importance of considering social and familial factors in religious conversion. PMID:25664141

Economic and labor market forces matter for worker well-being.

PubMed

Tay, Louis; Harter, James K

2013-07-01

In light of recent interest in societal subjective well-being, policies that seek to improve the economy and labor markets need to address the question of whether economic factors matter for worker well-being, specifically job satisfaction. In a worldwide representative poll of 136 nations, economic factors are associated with job satisfaction beyond demographic and job factors. Hierarchical linear modeling showed that higher national GDP and job optimism was associated with job satisfaction, whereas higher unemployment was associated with job dissatisfaction. Mediational analyses revealed that economic variables (GDP and job optimism) were partially mediated by job satisfaction in predicting life satisfaction; full mediation was found for unemployment. In a second study, time series regression of monthly data from a nationally representative poll in the United States from 2008 to 2011 revealed that unemployment rate was significantly associated with job dissatisfaction over time. There was some evidence that prior unemployment rates predicted job satisfaction at a higher level than job satisfaction predicted unemployment rates, suggesting that economic factors lead to job (dis)satisfaction rather than the converse. Theoretical and practical implications are discussed. © 2013 The Authors. Applied Psychology: Health and Well-Being © 2013 The International Association of Applied Psychology.

The Preclose Technique in Percutaneous Endovascular Aortic Repair: A Systematic Literature Review and Meta-analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jaffan, Abdel Aziz A., E-mail: aajaffan@gmail.com; Prince, Ethan A., E-mail: eprince@lifespan.org; Hampson, Christopher O., E-mail: christopherohampson@gmail.com

2013-06-15

Purpose. To establish the efficacy and safety of the preclose technique in total percutaneous endovascular aortic repair (PEVAR).MethodsA systematic literature search of Medline database was conducted for series on PEVAR published between January 1999 and January 2012.ResultsThirty-six articles comprising 2,257 patients and 3,606 arterial accesses were included. Anatomical criteria used to exclude patients from undergoing PEVAR were not uniform across all series. The technical success rate was 94 % per arterial access. Failure was unilateral in the majority (93 %) of the 133 failed PEVAR cases. The groin complication rate in PEVAR was 3.6 %; a minority (1.6 %) ofmore » these groin complications required open surgery. The groin complication rate in failed PEVAR cases converted to groin cutdown was 6.1 %. A significantly higher technical success rate was achieved when arterial access was performed via ultrasound guidance. Technical failure rate was significantly higher with larger sheath size ({>=}20F). Conclusion. The preclose technique in PEVAR has a high technical success rate and a low groin complication rate. Technical success tends to increase with ultrasound-guided arterial access and decrease with larger access. When failure occurs, it is unilateral in the majority of cases, and conversion to surgical cutdown does not appear to increase the operative risk.« less

Comparative efficacy of tilmicosin versus tulathromycin as a metaphylactic antimicrobial in feedlot calves at moderate risk for respiratory disease.

PubMed

Van Donkersgoed, Joyce; Merrill, John; Hendrick, Steven

2008-01-01

The purpose of this study was to compare the efficacy and cost-effectiveness of tilmicosin (MIC) versus tulathromycin (DRAX) as a metaphylactic antimicrobial in feedlot calves at moderate risk for bovine respiratory disease (BRD). Calves that received DRAX had significantly (P < or = .05) lower initial BRD treatment rates compared with calves that received MIC. However, there were no significant differences in the BRD relapse rate, railer rate, total mortality rate, BRD mortality rate, average daily gain, and dry matter conversion between the two groups. The economic advantage of the MIC group was Can$8.29/animal. Based on these results, while DRAX was more efficacious in reducing initial treatments for BRD in feedlot calves at moderate risk for disease, MIC was more cost-effective. The lower initial BRD treatment costs in the DRAX group did not offset the higher metaphylactic cost of DRAX.

The influence of IQ stratification on WAIS-III/WMS-III FSIQ-general memory index discrepancy base-rates in the standardization sample.

PubMed

Hawkins, K A; Tulsky, D S

2001-11-01

Since memory performance expectations may be IQ-based, unidirectional base rate data for IQ-Memory Score discrepancies are provided in the WAIS-III/WMS-III Technical Manual. The utility of these data partially rests on the assumption that discrepancy base rates do not vary across ability levels. FSIQ stratified base rate data generated from the standardization sample, however, demonstrate substantial variability across the IQ spectrum. A superiority of memory score over FSIQ is typical at lower IQ levels, whereas the converse is true at higher IQ levels. These data indicate that the use of IQ-memory score unstratified "simple difference" tables could lead to erroneous conclusions for clients with low or high IQ. IQ stratified standardization base rate data are provided as a complement to the "predicted difference" method detailed in the Technical Manual.

Detection of serum antibodies cross-reacting with Mycobacterium avium subspecies paratuberculosis and beta-cell antigen zinc transporter 8 homologous peptides in patients with high-risk proliferative diabetic retinopathy.

PubMed

Pinna, Antonio; Masala, Speranza; Blasetti, Francesco; Maiore, Irene; Cossu, Davide; Paccagnini, Daniela; Mameli, Giuseppe; Sechi, Leonardo A

2014-01-01

MAP3865c, a Mycobacterium avium subspecies paratuberculosis (MAP) cell membrane protein, has a relevant sequence homology with zinc transporter 8 (ZnT8), a beta-cell membrane protein involved in Zn++ transportation. Recently, antibodies recognizing MAP3865c epitopes have been shown to cross-react with ZnT8 in type 1 diabetes patients. The purpose of this study was to detect antibodies against MAP3865c peptides in patients with high-risk proliferative diabetic retinopathy and speculate on whether they may somehow be involved in the pathogenesis of this severe retinal disorder. Blood samples were obtained from 62 type 1 and 80 type 2 diabetes patients with high-risk proliferative diabetic retinopathy and 81 healthy controls. Antibodies against 6 highly immunogenic MAP3865c peptides were detected by indirect ELISA. Type 1 diabetes patients had significantly higher rates of positive antibodies than controls. Conversely, no statistically significant differences were found between type 2 diabetes patients and controls. After categorization of type 1 diabetes patients into two groups, one with positive, the other with negative antibodies, we found that they had similar mean visual acuity (∼ 0.6) and identical rates of vitreous hemorrhage (28.6%). Conversely, Hashimoto's thyroiditis prevalence was 4/13 (30.7%) in the positive antibody group and 1/49 (2%) in the negative antibody group, a statistically significant difference (P = 0.016). This study confirmed that type 1 diabetes patients have significantly higher rates of positive antibodies against MAP/ZnT8 peptides, but failed to find a correlation between the presence of these antibodies and the severity degree of high-risk proliferative diabetic retinopathy. The significantly higher prevalence of Hashimoto's disease among type 1 diabetes patients with positive antibodies might suggest a possible common environmental trigger for these conditions.

Photopolymerization of N,N-dimethylaminobenzyl alcohol as amine co-initiator for light-cured dental resins.

PubMed

Schroeder, Walter F; Cook, Wayne D; Vallo, Claudia I

2008-05-01

The present study was carried out in order to assess the suitability of N,N-dimethylaminobenzyl alcohol (DMOH) as co-initiator of camphorquinone (CQ) and 1-phenyl-1,2-propanedione (PPD) in light-cured dental resins. DMOH was synthesized and used as co-initiator for the photopolymerization of a model resin based on {2,2-bis[4-(2-hydroxy-3-methacryloxyprop-1-oxy)phenyl]propane} (Bis-GMA)/triethylene glycol dimethacrylate (TEGDMA). Experimental formulations containing CQ or PPD in combination with DMOH at different concentrations were studied. The photopolymerization was carried out by means of a commercial light-emitting diode (LED) curing unit. The evolution of double bonds consumption versus irradiation time was followed by near-infrared spectroscopy (NIR). The photon absorption efficiency (PAE) of the photopolymerization process was calculated from the spectral distribution of the LED unit and the molar absorption coefficient distributions of PPD and CQ. DMOH is an efficient photoreducer of CQ and PPD resulting in higher polymerization rate and higher double bond conversion compared with dimethylaminoethylmethacrylate. The PAE for PPD was higher than that for CQ. However, the polymerization initiated by PPD progressed at a lower rate and exhibited lower values of final conversion compared with the resins containing CQ. This observation indicates that the lower polymerization rate of the PPD/amine system should be explained in terms of the mechanism of generating primary radicals by PPD, which is less efficient compared with CQ. The DMOH/benzoyl peroxide redox system, has recently been proposed as a more biocompatible accelerator for the polymerization of bone cements based on poly(methyl methacrylate), because cytotoxity tests have demonstrated that DMOH possesses better biocompatibility properties compared with traditional tertiary amines. The results obtained in the present study reveal the suitability of the CQ/DMOH initiator system for the polymerization of light-cured dental composites.

Particle acceleration with anomalous pitch angle scattering in 2D magnetohydrodynamic reconnection simulations

NASA Astrophysics Data System (ADS)

Borissov, A.; Kontar, E. P.; Threlfall, J.; Neukirch, T.

2017-09-01

The conversion of magnetic energy into other forms (such as plasma heating, bulk plasma flows, and non-thermal particles) during solar flares is one of the outstanding open problems in solar physics. It is generally accepted that magnetic reconnection plays a crucial role in these conversion processes. In order to achieve the rapid energy release required in solar flares, an anomalous resistivity, which is orders of magnitude higher than the Spitzer resistivity, is often used in magnetohydrodynamic (MHD) simulations of reconnection in the corona. The origin of Spitzer resistivity is based on Coulomb scattering, which becomes negligible at the high energies achieved by accelerated particles. As a result, simulations of particle acceleration in reconnection events are often performed in the absence of any interaction between accelerated particles and any background plasma. This need not be the case for scattering associated with anomalous resistivity caused by turbulence within solar flares, as the higher resistivity implies an elevated scattering rate. We present results of test particle calculations, with and without pitch angle scattering, subject to fields derived from MHD simulations of two-dimensional (2D) X-point reconnection. Scattering rates proportional to the ratio of the anomalous resistivity to the local Spitzer resistivity, as well as at fixed values, are considered. Pitch angle scattering, which is independent of the anomalous resistivity, causes higher maximum energies in comparison to those obtained without scattering. Scattering rates which are dependent on the local anomalous resistivity tend to produce fewer highly energised particles due to weaker scattering in the separatrices, even though scattering in the current sheet may be stronger when compared to resistivity-independent scattering. Strong scattering also causes an increase in the number of particles exiting the computational box in the reconnection outflow region, as opposed to along the separatrices as is the case in the absence of scattering.

Electroviscous effect and electrokinetic energy conversion in time periodic pressure-driven flow through a parallel-plate nanochannel with surface charge-dependent slip

NASA Astrophysics Data System (ADS)

Buren, Mandula; Jian, Yongjun; Zhao, Yingchun; Chang, Long

2018-05-01

In this paper we analytically investigate the electroviscous effect and electrokinetic energy conversion in the time periodic pressure-driven flow of an incompressible viscous Newtonian liquid through a parallel-plate nanochannel with surface charge-dependent slip. Analytical and semi-analytical solutions for electric potential, velocity and streaming electric field are obtained and are utilized to compute electrokinetic energy conversion efficiency. The results show that velocity amplitude and energy conversion efficiency are reduced when the effect of surface charge on slip length is considered. The surface charge effect increases with zeta potential and ionic concentration. In addition, the energy conversion efficiency is large when the ratio of channel half-height to the electric double layer thickness is small. The boundary slip results in a large increase in energy conversion. Higher values of the frequency of pressure pulsation lead to higher values of the energy conversion efficiency. We also obtain the energy conversion efficiency in constant pressure-driven flow and find that the energy conversion efficiency in periodical pressure-driven flow becomes larger than that in constant pressure-driven flow when the frequency is large enough.

Interactions Between Atmospheric Aerosols and Marine Boundary Layer Clouds on Regional and Global Scales

NASA Astrophysics Data System (ADS)

Wang, Zhen

Airborne aerosols are crucial atmospheric constituents that are involved in global climate change and human life qualities. Understanding the nature and magnitude of aerosol-cloud-precipitation interactions is critical in model predictions for atmospheric radiation budget and the water cycle. The interactions depend on a variety of factors including aerosol physicochemical complexity, cloud types, meteorological and thermodynamic regimes and data processing techniques. This PhD work is an effort to quantify the relationships among aerosol, clouds, and precipitation on both global and regional scales by using satellite retrievals and aircraft measurements. The first study examines spatial distributions of conversion rate of cloud water to rainwater in warm maritime clouds over the globe by using NASA A-Train satellite data. This study compares the time scale of the onset of precipitation with different aerosol categories defined by values of aerosol optical depth, fine mode fraction, and Angstrom Exponent. The results indicate that conversion time scales are actually quite sensitive to lower tropospheric static stability (LTSS) and cloud liquid water path (LWP), in addition to aerosol type. Analysis shows that tropical Pacific Ocean is dominated by the highest average conversion rate while subtropical warm cloud regions (far northeastern Pacific Ocean, far southeastern Pacific Ocean, Western Africa coastal area) exhibit the opposite result. Conversion times are mostly shorter for lower LTSS regimes. When LTSS condition is fixed, higher conversion rates coincide with higher LWP and lower aerosol index categories. After a general global view of physical property quantifications, the rest of the presented PhD studies is focused on regional airborne observations, especially bulk cloud water chemistry and aerosol aqueous-phase reactions during the summertime off the California coast. Local air mass origins are categorized into three distinct types (ocean, ships, and land) with their influences on cloud water composition examined and implications of wet deposition discussed. Chemical analysis of cloud water samples indicates a wide pH range between 2.92 and 7.58, with an average as 4.46. The highest pH values were observed north of San Francisco, coincident with the strongest land mass influence (e.g. Si, B, and Cs). Conversely, the lowest pH values were observed south of San Francisco where there is heavy ship traffic, resulting in the highest concentrations of sulfate, nitrate, V, Fe, Al, P, Cd, Ti, Sb, P, and Mn. The acidic cloud environment with influences from various air mass types can affect the California coastal aquatic ecosystem since it can promote the conversion of micronutrients to more soluble forms. Beyond characterization of how regional air mass sources affect cloud water composition, aircraft cloud water collection provides precious information on tracking cloud processing with specific species such as oxalic acid, which is the most abundant dicarboxylic acid in tropospheric aerosols. Particular attention is given to explore relationship between detected metals with oxalate aqueous-phase production mechanisms. A number of case flights show that oxalate concentrations drop by nearly an order of magnitude relative to samples in the same vicinity with similar environmental and cloud physical conditions. Such a unique feature was consistent with an inverse relationship between oxalate and Fe. In order to examine the hypothesis that oxalate decreasing is potentially related to existing of Fe, chemistry box model simulations were conducted. The prediction results show that the loss of oxalate due to the photolysis of iron oxalato complexes is likely a significant oxalate sink in the study region due to the ubiquity of oxalate precursors, clouds, and metal emissions from ships, the ocean, and continental sources.

Conversion tables for use with the National Fire-Danger Rating System in the Intermountain area

Treesearch

Dwight S. Stockstad; Richard J. Barney

1964-01-01

Two tables prepared for use with the National Fire-Danger Rating System replace 10 tables previously used with the Model-8 Fire-Danger Rating System. They provide for the conversion of Spread Index values at various altitudes, aspects, and times of day. A rate of spread table facilitates converting Spread Index values to chains per hour of perimeter increase for...

Does quality improvement work? Evaluation of the Organ Donation Breakthrough Collaborative.

PubMed

Howard, David H; Siminoff, Laura A; McBride, Virginia; Lin, Monica

2007-12-01

The Organ Donation Breakthrough Collaborative is a quality improvement initiative to encourage adoption of "best practices" for identifying potential donors and obtaining consent for deceased organ donation. We evaluate the impact of the first phase on organ donation rates. We study donation rates in the 95 hospitals that participated in the first phase and a control group of 125 hospitals. We use a controlled pre/post design. The preperiod is the year before the start of the Collaborative (September 2002 to August 2003), the postperiod is the final 6 months of the first phase (March 2004 to August 2004). We use administrative data from the Organ Procurement and Transplantation Network to compute the conversion rate in each hospital group and time period. The conversion rate is the proportion of eligible donors who became actual donors. Preperiod conversion rates in Collaborative and control hospitals were similar: 52 and 51 percent, respectively. In the postperiod, the conversion rate increased to 60 percent among Collaborative hospitals and remained at 51 percent among control hospitals. The relative change was 8 percentage points (95 percent confidence interval: 2-13: p<.001). Our findings suggest that the Breakthrough Collaborative led to an increase in donation rates at participating hospitals.

Retrospective Conversion: A Question of Time, Standards, and Purpose.

ERIC Educational Resources Information Center

Valentine, Phyllis A.; McDonald, David R.

1986-01-01

Examines the factors that determine the cost of retrospective conversion (definition of conversion, standards of acceptance, method of conversion, hit rate, standards for creation of machine-readable records for nonhits); reports results of cost study at University of Michigan library; and introduces an alternative strategy for discussion. Seven…

Estimating bacterial production in marine waters from the simultaneous incorporation of thymidine and leucine.

PubMed

Chin-Leo, G; Kirchman, D L

1988-08-01

We examined the simultaneous incorporation of [H]thymidine and [C]leucine to obtain two independent indices of bacterial production (DNA and protein syntheses) in a single incubation. Incorporation rates of leucine estimated by the dual-label method were generally higher than those obtained by the single-label method, but the differences were small (dual/single = 1.1 +/- 0.2 [mean +/- standard deviation]) and were probably due to the presence of labeled leucyl-tRNA in the cold trichloroacetic acid-insoluble fraction. There were no significant differences in thymidine incorporation between dual- and single-label incubations (dual/ single = 1.03 +/- 0.13). Addition of the two substrates in relatively large amounts (25 nM) did not apparently increase bacterial activity during short incubations (<5 h). With the dual-label method we found that thymidine and leucine incorporation rates covaried over depth profiles of the Chesapeake Bay. Estimates of bacterial production based on thymidine and leucine differed by less than 25%. Although the need for appropriate conversion factors has not been eliminated, the dual-label approach can be used to examine the variation in bacterial production while ensuring that the observed variation in incorporation rates is due to real changes in bacterial production rather than changes in conversion factors or introduction of other artifacts.

Communication nonaccommodation in family conversations about end-of-life health decisions.

PubMed

Scott, Allison M; Caughlin, John P

2015-01-01

Furthering our understanding of how communication can improve end-of-life decision making requires a shift in focus from whether people talk to how people talk about end-of-life health decisions. This study used communication accommodation theory to examine the extent to which communication nonaccommodation distinguished more from less successful end-of-life conversations among family members. We analyzed elicited conversations about end-of-life health decisions from 121 older parent/adult child dyads using outside ratings of communication over- and underaccommodation and self-reported conversational outcomes. Results of multilevel linear modeling revealed that outside ratings of underaccommodation predicted self-reported and partner-reported uncertainty, and ratings of overaccommodation predicted self-reported decision-making efficacy and change in concordance accuracy. We discuss the methodological, theoretical, and practical implications of these findings.

Time-Dependent Effect of Refrigeration on Viscosity and Conversion Kinetics of Dental Adhesive Resins

PubMed Central

Faria-e-Silva, André L; Piva, Evandro; Moraes, Rafael R

2010-01-01

Objectives: This study evaluated the effect of refrigeration at 4°C and post-refrigeration times (immediate, 5, 10, 15, or 20 min) on the viscosity and conversion kinetics of adhesive bonding resins. Methods: Scotchbond Dual-Cure (3M ESPE) and Clearfil SE Bond (Kuraray) were tested. Control samples were kept at 25°C for 24 h. At each post-refrigeration time, the temperature was checked with a K-type thermocouple. Viscosity measurements as a function of temperature were performed using a cone-plate viscometer. Real-time polymerization was monitored by infrared spectroscopy. Degree of conversion (DC) was calculated for each second during polymerization, and the rate of polymerization analyzed. Data were separately submitted to two-way ANOVA and Tukey’s test (P<.05). Results: Clearfil presented faster increase in temperature after exposure to room temperature than Scotchbond. A continuous decrease in viscosity (Pa.s) was observed for both Scotchbond (0.49, 0.34, 0.30, 0.26, 0.23, 0.23) and Clearfil (0.38, 0.37, 0.34, 0.25, 0.24, 0.22). For Scotchbond, higher final DC was detected for the control (62.7%) compared with the immediate (53.3%) and 5 min (54.7%) groups. For Clearfil, the control sample (81.4%) showed higher DC than all refrigerated groups (68.8–69.5%). Clearfil always showed significantly higher DC than Scotchbond. Conclusions: Refrigeration presented a significant time- and material-dependent effect on the viscosity and polymerization kinetics of the bonding resins. Under clinical conditions, adhesive agents should be removed from the refrigerator at least 20 min before being used. PMID:20396445

49 CFR 583.14 - Currency conversion rate.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 7 2013-10-01 2013-10-01 false Currency conversion rate. 583.14 Section 583.14 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AUTOMOBILE PARTS CONTENT LABELING § 583.14 Currency...

49 CFR 583.14 - Currency conversion rate.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 7 2011-10-01 2011-10-01 false Currency conversion rate. 583.14 Section 583.14 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AUTOMOBILE PARTS CONTENT LABELING § 583.14 Currency...

49 CFR 583.14 - Currency conversion rate.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 7 2012-10-01 2012-10-01 false Currency conversion rate. 583.14 Section 583.14 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AUTOMOBILE PARTS CONTENT LABELING § 583.14 Currency...

49 CFR 583.14 - Currency conversion rate.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 7 2010-10-01 2010-10-01 false Currency conversion rate. 583.14 Section 583.14 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AUTOMOBILE PARTS CONTENT LABELING § 583.14 Currency...

49 CFR 583.14 - Currency conversion rate.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 7 2014-10-01 2014-10-01 false Currency conversion rate. 583.14 Section 583.14 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AUTOMOBILE PARTS CONTENT LABELING § 583.14 Currency...

A Cooperative Conversion Project from Vertical File Hardcopy to Jacketed Microfiche.

ERIC Educational Resources Information Center

Worden, Diane D.

1981-01-01

Describes a cooperative project to convert a library's hardcopy materials to microfiche, including the steps involved in conversion, conversion costs, sources of funding, and staff performance rates. Six references are listed. (FM)

Conversational Memory Employing Cued and Free Recall.

ERIC Educational Resources Information Center

Benoit, Pamela J.; Benoit, William L.

1988-01-01

Tests two hypotheses: (1) that cued recall elicits significantly more conversational information than free recall; and (2) that conversational interactants recall more of their partner's utterances than their own. Finds cued recall produced significantly higher amounts of remembering than free recall. (MS)

Outcome trends and safety measures after 30 years of laparoscopic cholecystectomy: a systematic review and pooled data analysis.

PubMed

Pucher, Philip H; Brunt, L Michael; Davies, Neil; Linsk, Ali; Munshi, Amani; Rodriguez, H Alejandro; Fingerhut, Abe; Fanelli, Robert D; Asbun, Horacio; Aggarwal, Rajesh

2018-05-01

Laparoscopic cholecystectomy (LC), one of the most commonly performed surgical procedures, remains associated with significant major morbidity including bile leak and bile duct injury (BDI). The effect of changes in practice over time, and of interventions to improve patient safety, on morbidity rates is not well understood. The aim of this review was to describe current incidence rates and trends for BDI and other complications during and after LC, and to identify risk factors and preventative measures associated with morbidity and BDI. PubMed, MEDLINE, and Web of Science database searches and data extraction were conducted for studies which reported individual complications and complication rates following laparoscopic cholecystectomy in a representative population. Outcomes data were pooled. Meta-regression analysis was performed to assess factors associated with conversion, morbidity, and BDI rates. One hundred and fifty-one studies reporting outcomes for 505,292 patients were included in the final quantitative synthesis. Overall morbidity, BDI, and mortality rates were 1.6-5.3%, 0.32-0.52%, and 0.08-0.14%, respectively. Reported BDI rates reduced over time (1994-1999: 0.69(0.52-0.84)% versus 2010-2015 0.22(0.02-0.40)%, p = 0.011). Meta-regression analysis suggested higher conversion rates in developed versus developing countries (4.7 vs. 3.4%), though a greater degree of reporting bias was present in these studies, with no other significant associations identified. Overall, trends suggest a reduction in BDI over time with unchanged morbidity and mortality rates. However, data and reporting are heterogenous. Establishment of international outcomes registries should be considered.

Cross-Cultural Comparisons of the Perceived Importance of Conversational Constraints.

ERIC Educational Resources Information Center

Kim, Min-Sun

1994-01-01

Investigates how cultural groups differ in the relative importance they attach to conversational constraints. Suggests that the perceived importance of clarity is higher in the more individualistic cultures but that the perceived importance of avoiding hurting the hearer's feelings and of minimizing imposition is higher in the more collectivistic…

Biorefinery of instant noodle waste to biofuels.

PubMed

Yang, Xiaoguang; Lee, Sang Jun; Yoo, Hah Young; Choi, Han Suk; Park, Chulhwan; Kim, Seung Wook

2014-05-01

Instant noodle waste, one of the main residues of the modern food industry, was employed as feedstock to convert to valuable biofuels. After isolation of used oil from the instant noodle waste surface, the starch residue was converted to bioethanol by Saccharomyces cerevisiae K35 with simultaneous saccharification and fermentation (SSF). The maximum ethanol concentration and productivity was 61.1g/l and 1.7 g/lh, respectively. After the optimization of fermentation, ethanol conversion rate of 96.8% was achieved within 36 h. The extracted oil was utilized as feedstock for high quality biodiesel conversion with typical chemical catalysts (KOH and H2SO4). The optimum conversion conditions for these two catalysts were estimated; and the highest biodiesel conversion rates were achieved 98.5% and 97.8%, within 2 and 3h, respectively. The high conversion rates of both bioethanol and biodiesel demonstrate that novel substrate instant noodle waste can be an attractive biorefinery feedstock in the biofuels industry. Copyright © 2014 Elsevier Ltd. All rights reserved.

Renal function improvement in liver transplant recipients after early everolimus conversion: A clinical practice cohort study in Spain.

PubMed

Bilbao, Itxarone; Salcedo, Magdalena; Gómez, Miguel Angel; Jimenez, Carlos; Castroagudín, Javier; Fabregat, Joan; Almohalla, Carolina; Herrero, Ignacio; Cuervas-Mons, Valentín; Otero, Alejandra; Rubín, Angel; Miras, Manuel; Rodrigo, Juan; Serrano, Trinidad; Crespo, Gonzalo; De la Mata, Manuel; Bustamante, Javier; Gonzalez-Dieguez, M Luisa; Moreno, Antonia; Narvaez, Isidoro; Guilera, Magda

2015-08-01

A national, multicenter, retrospective study was conducted to assess the results obtained for liver transplant recipients with conversion to everolimus in daily practice. The study included 477 recipients (481 transplantations). Indications for conversion to everolimus were renal dysfunction (32.6% of cases), hepatocellular carcinoma (HCC; 30.2%; prophylactic treatment for 68.9%), and de novo malignancy (29.7%). The median time from transplantation to conversion to everolimus was 68.7 months for de novo malignancy, 23.8 months for renal dysfunction, and 7.1 months for HCC and other indications. During the first year of treatment, mean everolimus trough levels were 5.4 (standard deviation [SD], 2.7) ng/mL and doses remained stable (1.5 mg/day) from the first month after conversion. An everolimus monotherapy regimen was followed by 28.5% of patients at 12 months. Patients with renal dysfunction showed a glomerular filtration rate (4-variable Modification of Diet in Renal Disease) increase of 10.9 mL (baseline mean, 45.8 [SD, 25.3] versus 57.6 [SD, 27.6] mL/minute/1.73 m(2) ) at 3 months after everolimus initiation (P < 0.001), and 6.8 mL at 12 months. Improvement in renal function was higher in patients with early conversion (<1 year). Adverse events were the primary reason for discontinuation in 11.2% of cases. The probability of survival at 3 years after conversion to everolimus was 83.0%, 71.1%, and 59.5% for the renal dysfunction, de novo malignancy, and HCC groups, respectively. Everolimus is a viable option for the treatment of renal dysfunction, and earlier conversion is associated with better recovery of renal function. Prospective studies are needed to confirm advantages in patients with malignancy. © 2015 American Association for the Study of Liver Diseases.

Water levels shape fishing participation in flood-control reservoirs

USGS Publications Warehouse

Miranda, Leandro E.; Meals, K. O.

2013-01-01

We examined the relationship between fishing effort (hours fished) and average March–May water level in 3 flood control reservoirs in Mississippi. Fishing effort increased as water level rose, peaked at intermediate water levels, and decreased at high water levels. We suggest that the observed arched-shaped relationship is driven by the shifting influence of fishability (adequacy of the fishing circumstances from an angler's perspective) and catch rate along a water level continuum. Fishability reduces fishing effort during low water, despite the potential for higher catch rates. Conversely, reduced catch rates and fishability at high water also curtail effort. Thus, both high and low water levels seem to discourage fishing effort, whereas anglers seem to favor intermediate water levels. Our results have implications for water level management in reservoirs with large water level fluctuations.

Cellulosic bioethanol production from Jerusalem artichoke (Helianthus tuberosus L.) using hydrogen peroxide-acetic acid (HPAC) pretreatment.

PubMed

Song, Younho; Wi, Seung Gon; Kim, Ho Myeong; Bae, Hyeun-Jong

2016-08-01

Jerusalem artichoke (JA) is recognized as a suitable candidate biomass crop for bioethanol production because it has a rapid growth rate and high biomass productivity. In this study, hydrogen peroxide-acetic acid (HPAC) pretreatment was used to enhance the enzymatic hydrolysis and to effectively remove the lignin of JA. With optimized enzyme doses, synergy was observed from the combination of three different enzymes (RUT-C30, pectinase, and xylanase) which provided a conversion rate was approximately 30% higher than the rate with from treatment with RUT-C30 alone. Fermentation of the JA hydrolyzates by Saccharomyces cerevisiae produced a fermentation yield of approximately 84%. Therefore, Jerusalem artichoke has potential as a bioenergy crop for bioethanol production. Copyright © 2016 Elsevier Ltd. All rights reserved.

Revisional bariatric surgery for failed gastric banding in Asia: a review of choice of revisional procedure, surgical technique and postoperative complication rates.

PubMed

Bhasker, A; Gadgil, M; Muda, N H; Lotwala, V; Lakdawala, M A

2011-02-01

In Asia, long-term weight loss results of gastric banding have been unsatisfactory. Bands are associated with higher complication rates, which result in a high reoperation rate. The aim of this paper is to discuss the choice of revisional procedure, operative technique and evaluate the postoperative complication rates. Between January 2007 and January 2010, we operated on 41 patients who were included retrospectively in this series. The most common reason for band removal was failure to lose adequate weight. Of those patients, 40 underwent band removal and conversion to a revisional bariatric surgery concomitantly; one patient's procedure was deferred to a later date. LSG was performed in 26 and LRYGB in 15. The highlights of the operative technique were meticulous dissection, complete removal of the pseudocapsule, choosing the right stapler cartridge, oversewing and inverting the entire staple line, and complete dissection of the left crus and pars flaccid. The median duration of surgery was 85 min (range, 55-180 min). There was no conversion to open surgery. The median stay in the hospital was 4 d (range, 2-7 d). There were no leaks or any other major complications in the postoperative period. Concomitant revisional procedure after removal of gastric band is safe and feasible. The operative technique followed at our center has had an extremely low postoperative morbidity rate and a 0% leak rate. © 2010 Japan Society for Endoscopic Surgery, Asia Endosurgery Task Force and Blackwell Publishing Asia Pty Ltd.

Incidence of infection after early intramedullary nailing of open tibial shaft fractures stabilized with pinless external fixators

PubMed Central

Kulshrestha, Vikas

2008-01-01

Background: A major drawback of conventional fixator system is the penetration of fixator pins into the medullary canal. The pins create a direct link between the medullary cavity and outer environment, leading to higher infection rates on conversion to intramedullary nailing. This disadvantage is overcome by the AO pinless fixator, in which the trocar points are clamped onto the outer cortex without penetrating it. This study was designed to evaluate the role of AO pinless fixators in primary stabilization of open diaphyseal tibial fractures that received staged treatment because of delayed presentation or poor general condition. We also analyzed the rate of infection on early conversion to intramedullary nail. Materials and Methods: This study is a retrospective review of 30 open diaphyseal fractures of tibia, which were managed with primary stabilization with pinless fixator and early exchange nailing. Outcome was evaluated in terms of fracture union and rate of residual infection. The data were compared with that available in the literature. Results: All the cases were followed up for a period of 2 years. The study includes Gustilo type 1 (n=10), 14 Gustilo type 2 (n=14), and type3 (n=6) cases. 6 cases (20%) had clamp site infection, 2 cases (6.7%) had deep infection, and in 28 cases (93%) the fracture healed and consolidated well. Conclusion: This study has highlighted the valuable role of pinless external fixator in the management of open tibial fractures in terms of safety and ease of application as well as the advantage of early conversion to intramedullary implant without the risk of deep infection. PMID:19753227

Effect of polyvinylpyrrolidone on mesoporous silica morphology and esterification of lauric acid with 1-butanol catalyzed by immobilized enzyme

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Jinyu; Zhou, Guowei, E-mail: guoweizhou@hotmail.com; Jiang, Bin

2014-05-01

Mesoporous silica materials with a range of morphology evolution, i.e., from curved rod-shaped mesoporous silica to straight rod-shaped mesoporous silica, were successfully prepared using polyvinylpyrrolidone (PVP) and triblock copolymer as dual template. The effects of PVP molecular weight and concentration on mesoporous silica structure parameters were studied. Results showed that surface area and pore volume continuously decreased with increased PVP molecular weight. Mesoporous silica prepared with PVP K30 also possessed larger pore diameter, interplanar spacing (d{sub 100}), and cell parameter (a{sub 0}) than that prepared with PVP K15 and PVP K90. In addition, with increased PVP concentration, d{sub 100} andmore » a{sub 0} continuously decreased. The mechanism of morphology evolution caused by the change in PVP concentration was investigated. The conversion rate of lauric acid with 1-butanol catalyzed by immobilized Porcine pancreatic lipase (PPL) was also evaluated. Results showed that PPL immobilized on amino-functionalized straight rod-shaped mesoporous silica maintained 50% of its esterification conversion rate even after five cycles of use with a maximum conversion rate was about 90.15%. - Graphical abstract: Curved rod-shaped mesoporous silica can be obtained at low and the highest PVP concentration, while straight rod-shaped mesoporous silica can be obtained at higher PVP concentration. - Highlights: • Mesoporous silica with morphology evolution from CRMS to SRMS were prepared. • Effects of PVP molecular weight and concentration on silica morphology were studied. • A possible mechanism for the formation of morphology evolution SiO{sub 2} was proposed. • Esterification of lauric acid with 1-butanol catalyzed by immobilized PPL.« less

Conversion to eslicarbazepine acetate monotherapy

PubMed Central

French, Jacqueline; Jacobson, Mercedes P.; Pazdera, Ladislav; Gough, Mallory; Cheng, Hailong; Grinnell, Todd; Blum, David

2016-01-01

Objective: To assess the efficacy and safety of eslicarbazepine acetate (ESL) monotherapy. Methods: This post hoc pooled analysis of 2 randomized double-blind studies (093-045 and -046) included adults with partial-onset seizures medically uncontrolled by 1 or 2 antiepileptic drugs (AEDs). Following the baseline period (8 weeks), eligible patients were randomized 2:1 to receive ESL 1,600 mg or 1,200 mg once daily for 18 weeks; the primary endpoint was study exit by meeting predefined exit criteria (signifying worsening seizure control). In each study, treatment was considered effective if the upper 95% confidence limit for exit rate was lower than the historical control threshold (65.3%). Results: Pooled exit rates were as follows: ESL 1,600 mg = 20.6% (95% confidence interval: 15.6%–26.8%); ESL 1,200 mg = 30.8% (23.0%–40.5%). Use of 2 baseline AEDs or rescue medication, US location, epilepsy duration ≥20 years, and higher maximum baseline seizure frequency were associated with higher exit risks. Median percent reductions in standardized seizure frequency between baseline and the 18-week double-blind period were as follows: ESL 1,600 mg = 43.2%; ESL 1,200 mg = 35.7%; baseline carbamazepine use was associated with smaller reductions. Safety profiles were similar between ESL doses. Conclusions: Exit rates for ESL monotherapy (1,600 mg and 1,200 mg once daily) were lower than the historical control threshold, irrespective of baseline AED use and region, with no additional safety concerns identified. Clinical factors and location clearly influence treatment responses in conversion-to-monotherapy trials. Classification of evidence: This pooled analysis provides Class IV evidence that for adults with medically uncontrolled partial-onset seizures, ESL monotherapy is well tolerated and effective. PMID:26911639

Conversion to eslicarbazepine acetate monotherapy: A pooled analysis of 2 phase III studies.

PubMed

Sperling, Michael R; French, Jacqueline; Jacobson, Mercedes P; Pazdera, Ladislav; Gough, Mallory; Cheng, Hailong; Grinnell, Todd; Blum, David

2016-03-22

To assess the efficacy and safety of eslicarbazepine acetate (ESL) monotherapy. This post hoc pooled analysis of 2 randomized double-blind studies (093-045 and -046) included adults with partial-onset seizures medically uncontrolled by 1 or 2 antiepileptic drugs (AEDs). Following the baseline period (8 weeks), eligible patients were randomized 2:1 to receive ESL 1,600 mg or 1,200 mg once daily for 18 weeks; the primary endpoint was study exit by meeting predefined exit criteria (signifying worsening seizure control). In each study, treatment was considered effective if the upper 95% confidence limit for exit rate was lower than the historical control threshold (65.3%). Pooled exit rates were as follows: ESL 1,600 mg = 20.6% (95% confidence interval: 15.6%-26.8%); ESL 1,200 mg = 30.8% (23.0%-40.5%). Use of 2 baseline AEDs or rescue medication, US location, epilepsy duration ≥20 years, and higher maximum baseline seizure frequency were associated with higher exit risks. Median percent reductions in standardized seizure frequency between baseline and the 18-week double-blind period were as follows: ESL 1,600 mg = 43.2%; ESL 1,200 mg = 35.7%; baseline carbamazepine use was associated with smaller reductions. Safety profiles were similar between ESL doses. Exit rates for ESL monotherapy (1,600 mg and 1,200 mg once daily) were lower than the historical control threshold, irrespective of baseline AED use and region, with no additional safety concerns identified. Clinical factors and location clearly influence treatment responses in conversion-to-monotherapy trials. This pooled analysis provides Class IV evidence that for adults with medically uncontrolled partial-onset seizures, ESL monotherapy is well tolerated and effective. © 2016 American Academy of Neurology.

Boundary layer measurements of the OH radical in the vicinity of an isolated power plant plume - SO2 and NO2 chemical conversion times

NASA Technical Reports Server (NTRS)

Davis, D. D.; Philen, D.; Mcgee, T.; Heaps, W.

1979-01-01

Direct measurements of the OH radical in the vicinity of an isolated power plant plume are reported. These measurements were used to estimate the conversion time of SO2 to H2SO4-sulfate aerosol via the initiating step OH + SO2 + M yields HSO3. Using the near-high-noon measured value of OH (9.5 million per cu cm), resulted in a 1/e conversion time of 1.4 days. The latter lifetime would correspond to a conversion rate of about 2%/hr. When the lifetime calculation was modified to take into consideration the OH diurnal cycle, the 1/e conversion time for SO2 was found to be 4.4 days, giving an apparent overall rate of conversion of about 0.7%/hr. Similar calculations carried out for the conversion of NO2 to NHO3 resulted in 1/e lifetimes for NO2 of 2-3 h for midday time periods.

Subcritical hydrothermal liquefaction of cattle manure to bio-oil: Effects of conversion parameters on bio-oil yield and characterization of bio-oil.

PubMed

Yin, Sudong; Dolan, Ryan; Harris, Matt; Tan, Zhongchao

2010-05-01

In this study, cattle manure was converted to bio-oil by subcritical hydrothermal liquefaction in the presence of NaOH. The effects of conversion temperature, process gas, initial conversion pressure, residence time and mass ratio of cattle manure to water on the bio-oil yield were studied. The bio-oil was characterized in terms of elemental composition, higher heating value, ultraviolet-visible (UV/Vis) spectroscopy, Fourier transform infrared spectroscopy (FTIR), gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). Results showed that the bio-oil yield depended on the conversion temperature and the process gas. Higher initial conversion pressure, longer residence time and larger mass ratio of cattle manure to water, however, had negative impacts on the bio-oil yield. The higher heating value of bio-oil was 35.53MJ/kg on average. The major non-polar components of bio-oil were toluene, ethyl benzene and xylene, which are components of crude oil, gasoline and diesel. Copyright 2010 Elsevier Ltd. All rights reserved.

Hydrocarbon pyrolysis reactor experimentation and modeling for the production of solar absorbing carbon nanoparticles

NASA Astrophysics Data System (ADS)

Frederickson, Lee Thomas

Much of combustion research focuses on reducing soot particulates in emissions. However, current research at San Diego State University (SDSU) Combustion and Solar Energy Laboratory (CSEL) is underway to develop a high temperature solar receiver which will utilize carbon nanoparticles as a solar absorption medium. To produce carbon nanoparticles for the small particle heat exchange receiver (SPHER), a lab-scale carbon particle generator (CPG) has been built and tested. The CPG is a heated ceramic tube reactor with a set point wall temperature of 1100-1300°C operating at 5-6 bar pressure. Natural gas and nitrogen are fed to the CPG where natural gas undergoes pyrolysis resulting in carbon particles. The gas-particle mixture is met downstream with dilution air and sent to the lab scale solar receiver. To predict soot yield and general trends in CPG performance, a model has been setup in Reaction Design CHEMKIN-PRO software. One of the primary goals of this research is to accurately measure particle properties. Mean particle diameter, size distribution, and index of refraction are calculated using Scanning Electron Microscopy (SEM) and a Diesel Particulate Scatterometer (DPS). Filter samples taken during experimentation are analyzed to obtain a particle size distribution with SEM images processed in ImageJ software. These results are compared with the DPS, which calculates the particle size distribution and the index of refraction from light scattering using Mie theory. For testing with the lab scale receiver, a particle diameter range of 200-500 nm is desired. Test conditions are varied to understand effects of operating parameters on particle size and the ability to obtain the size range. Analysis of particle loading is the other important metric for this research. Particle loading is measured downstream of the CPG outlet and dilution air mixing point. The air-particle mixture flows through an extinction tube where opacity of the mixture is measured with a 532 nm laser and detector. Beer's law is then used to calculate particle loading. The CPG needs to produce a certain particle loading for a corresponding receiver test. By obtaining the particle loading in the system, the reaction conversion to solid carbon in the CPG can be calculated to measure the efficiency of the CPG. To predict trends in reaction conversion and particle size from experimentation, the CHEMKIN-PRO computer model for the CPG is run for various flow rates and wall temperature profiles. These predictions were a reason for testing at higher wall set point temperatures. Based on these research goals, it was shown that the CPG consistently produces a mean particle diameter of 200-400 nm at the conditions tested, fitting perfectly inside the desired range. This led to successful lab scale SPHER testing which produced a 10-point efficiency increase and 150°C temperature difference with particles present. Also, at 3 g/s dilution air flow rate, an efficiency of 80% at an outlet temperature above 800°C was obtained. Promise was shown at higher CPG experimental temperatures to produce higher reaction conversion, both experimentally and in the model. However, based on wall temperature data taken during experimentation, it is apparent that the CPG needs to have multiple heating zones with separate temperature controllers in order to have an isothermal zone rather than a parabolic temperature profile. As for the computer model, it predicted much higher reaction conversion at higher temperature. The mass fraction of fuel in the inlet stream was shown to not affect conversion while increasing residence time led to increasing conversion. Particle size distribution in the model was far off and showed a bimodal distribution for one of the statistical methods. Using the results from experimentation and modeling, a preliminary CPG design is presented that will operate in a 5MWth receiver system.

24 CFR 972.124 - Standards for identifying public housing developments subject to required conversion.

Code of Federal Regulations, 2010 CFR

2010-04-01

... March 16, 2009, the specified vacancy rate is 15 percent. For a conversion analysis performed after that... housing developments subject to required conversion. 972.124 Section 972.124 Housing and Urban Development... INDIAN HOUSING, DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT CONVERSION OF PUBLIC HOUSING TO TENANT-BASED...

Brief Report: A Scale for Rating Conversational Impairment in Autism Spectrum Disorder

ERIC Educational Resources Information Center

de Villiers, Jessica; Fine, Jonathan; Ginsberg, Gary; Vaccarella, Liezanne; Szatmari, Peter

2007-01-01

There are few well-standardized measures of conversational breakdown in Autism Spectrum Disorders (ASD). The study's objective was to develop a scale for measuring pragmatic impairments in conversations of individuals with ASD. We analyzed 46 semi-structured conversations of children and adolescents with high-functioning ASD using a functional…

Same admission laparoscopic cholecystectomy for acute cholecystitis: is the "golden 72 hours" rule still relevant?

PubMed

Tan, Jarrod K H; Goh, Joel C I; Lim, Janice W L; Shridhar, Iyer G; Madhavan, Krishnakumar; Kow, Alfred W C

2017-01-01

Studies have shown that same admission laparoscopic cholecystectomy (SALC) is superior to delayed laparoscopic cholecystectomy for acute cholecystitis (AC). While some proposed a"golden 72-hour" for SALC, the optimal timing remains controversial. The aim of the study was to compare the outcomes of SALC in AC patients with different time intervals from symptom onset. A retrospective analysis of 311 patients who underwent SALC for AC from June 2010-June 2015 was performed. Patients were divided into three groups based on the time interval between symptom onset and surgery: <4 days (E-SALC), 4-7 days (M-SALC), >7 (L-SALC). The mean duration of symptoms was 2(1-3), 5(4-7) and 9 (8-13) days for E-SALC, M-SALC and L-SALC, respectively (p < 0.001). Conversion rates were higher in the L-SALC group [E-SALC, 8.2% vs M-SALC, 9.6% vs L-SALC, 21.4%] (p = 0.048). The total length of stay was longer in patients with longer symptom duration [E-SALC, 4 (2-33) vs M-SALC, 2 (2-23) vs L-SALC, 7 (2-49)] (p < 0.001). Patients with AC presenting beyond 7 days of symptoms have higher conversion rates and longer length of stay associated with SALC. However, patients with less than a week of symptoms should be offered SALC. Copyright © 2016 International Hepato-Pancreato-Biliary Association Inc. Published by Elsevier Ltd. All rights reserved.

Selling the story: narratives and charisma in adults with TBI.

PubMed

Jones, Corinne A; Turkstra, Lyn S

2011-01-01

To examine storytelling performance behaviours in adults with traumatic brain injury (TBI) and relate these behaviours to perceived charisma and desirability as a conversation partner. Seven adult males with traumatic brain injury (TBI) told their accident narratives to a male confederate. Ten male undergraduate students rated 1-minute video clips from the beginning of each narrative using the Charismatic Leadership Communication Scale (CLCS). Raters also indicated whether or not they would like to engage in conversation with each participant. Of the performative behaviours analysed, gestures alone significantly influenced CLCS ratings and reported likelihood of engaging in future conversation with the participant. Post-hoc analysis revealed that speech rate was significantly correlated with all of the preceding measures. There was a significant correlation between self- and other-ratings of charisma. The findings suggest that aspects of non-verbal performance, namely gesture use and speech rate, influence how charismatic an individual is perceived to be and how likely someone is to engage in conversation with that person. Variability in these performance behaviours may contribute to the variation in social outcomes seen in the TBI population.

Fischer-Tropsch synthesis in supercritical phase carbon dioxide: Recycle rates

NASA Astrophysics Data System (ADS)

Soti, Madhav

With increasing oil prices and attention towards the reduction of anthropogenic CO2, the use of supercritical carbon dioxide for Fischer Tropsch Synthesis (FTS) is showing promise in fulfilling the demand of clean liquid fuels. The evidence of consumption of carbon dioxide means that it need not to be removed from the syngas feed to the Fischer Tropsch reactor after the gasification process. Over the last five years, research at SIUC have shown that FTS in supercritical CO2reduces the selectivities for methane, enhances conversion, reduces the net CO2produces in the coal to liquid fuels process and increase the life of the catalyst. The research has already evaluated the impact of various operating and feed conditions on the FTS for the once through process. We believe that the integration of unreacted feed recycle would enhance conversion, increase the yield and throughput of liquid fuels for the same reactor size. The proposed research aims at evaluating the impact of recycle of the unreacted feed gas along with associated product gases on the performance of supercritical CO2FTS. The previously identified conditions will be utilized and various recycle ratios will be evaluated in this research once the recycle pump and associated fittings have been integrated to the supercritical CO2FTS. In this research two different catalysts (Fe-Zn-K, Fe-Co-Zn-K) were analyzed under SC-FTS in different recycle rate at 350oC and 1200 psi. The use of recycle was found to improve conversion from 80% to close to 100% with both catalysts. The experiment recycle rate at 4.32 and 4.91 was clearly surpassing theoretical recycle curve. The steady state reaction rate constant was increased to 0.65 and 0.8 min-1 for recycle rate of 4.32 and 4.91 respectively. Carbon dioxide selectivity was decreased for both catalyst as it was converting to carbon monoxide. Carbon dioxide consumption was increased from 0.014 to 0.034 mole fraction. This concluded that CO2is being used in the system and converting which created the concentration of the feed gas higher inside the reactor. The research has provided the best conditions for the enhanced conversion while minimizing CO2formation. Though this research was not able to provide the optimal recycle rate it have created the path for the future research to proceed in the right direction. This reduction and utilization of CO2will help to reduce the cost of carbon dioxide removal and saves the environment from carbon dioxide emission.

Positively Biased Processing of Mother's Emotions Predicts Children's Social and Emotional Functioning.

PubMed

Donohue, Meghan Rose; Goodman, Sherryl H; Tully, Erin C

Risk for internalizing problems and social skills deficits likely emerges in early childhood when emotion processing and social competencies are developing. Positively biased processing of social information is typical during early childhood and may be protective against poorer psychosocial outcomes. We tested the hypothesis that young children with relatively less positively biased attention to, interpretations of, and attributions for their mother's emotions would exhibit poorer prosocial skills and more internalizing problems. A sample of 4- to 6-year-old children ( N =82) observed their mothers express happiness, sadness and anger during a simulated emotional phone conversation. Children's attention to their mother when she expressed each emotion was rated from video. Immediately following the phone conversation, children were asked questions about the conversation to assess their interpretations of the intensity of mother's emotions and misattributions of personal responsibility for her emotions. Children's prosocial skills and internalizing problems were assessed using mother-report rating scales. Interpretations of mother's positive emotions as relatively less intense than her negative emotions, misattributions of personal responsibility for her negative emotions, and lack of misattributions of personal responsibility for her positive emotions were associated with poorer prosocial skills. Children who attended relatively less to mother's positive than her negative emotions had higher levels of internalizing problems. These findings suggest that children's attention to, interpretations of, and attributions for their mother's emotions may be important targets of early interventions for preventing prosocial skills deficits and internalizing problems.

Ultrasound-assisted oxidation of dibenzothiophene with phosphotungstic acid supported on activated carbon.

PubMed

Liu, Liyan; Zhang, Yu; Tan, Wei

2014-05-01

Phosphotungstic acid (HPW) supported on activated carbon (AC) was applied to catalyze deep oxidation desulfurization of fuel oil with the assist of ultrasound. The sulfur-conversion rate was evaluated by measuring the concentration of dibenzothiophene (DBT) in n-octane before and after the oxidation. Supporting HPW on AC has been verified to play a positive role in UAOD process by a series of contrast tests, where only HPW, AC or a mixture of free HPW and AC was used. The influences of catalyst dose, ultrasound power, reaction temperature, H2O2:oil volume ratio and the reuse of catalyst on the catalytic oxidation desulfurization kinetics were investigated. The DBT conversion rate of the reaction catalyzed by supported HPW under ultrasound irradiation was higher than the summation of the reactions with HPW only and AC only as catalyst. With the increase of loading amount of HPW on AC, ultrasound power, H2O2:oil volume ratio and reaction temperature, the catalytic oxidation reactivity of DBT would be enhanced. The optimum loading amount of HPW was 10%, exceed which DBT conversion would no longer increase obviously. DBT could be completely converted under the optimized conditions (volume ratio of H2O2 to model oil: 1:10, mass ratio of the supported HPW to model oil: 1.25%, temperature: 70°C) after 9 min of ultrasound irradiation. Copyright © 2013 Elsevier B.V. All rights reserved.

Positively Biased Processing of Mother’s Emotions Predicts Children’s Social and Emotional Functioning

PubMed Central

Donohue, Meghan Rose; Goodman, Sherryl H.; Tully, Erin C.

2016-01-01

Risk for internalizing problems and social skills deficits likely emerges in early childhood when emotion processing and social competencies are developing. Positively biased processing of social information is typical during early childhood and may be protective against poorer psychosocial outcomes. We tested the hypothesis that young children with relatively less positively biased attention to, interpretations of, and attributions for their mother’s emotions would exhibit poorer prosocial skills and more internalizing problems. A sample of 4- to 6-year-old children (N=82) observed their mothers express happiness, sadness and anger during a simulated emotional phone conversation. Children’s attention to their mother when she expressed each emotion was rated from video. Immediately following the phone conversation, children were asked questions about the conversation to assess their interpretations of the intensity of mother’s emotions and misattributions of personal responsibility for her emotions. Children’s prosocial skills and internalizing problems were assessed using mother-report rating scales. Interpretations of mother’s positive emotions as relatively less intense than her negative emotions, misattributions of personal responsibility for her negative emotions, and lack of misattributions of personal responsibility for her positive emotions were associated with poorer prosocial skills. Children who attended relatively less to mother’s positive than her negative emotions had higher levels of internalizing problems. These findings suggest that children’s attention to, interpretations of, and attributions for their mother’s emotions may be important targets of early interventions for preventing prosocial skills deficits and internalizing problems. PMID:28348456

Fructose utilization during exercise in men: rapid conversion of ingested fructose to circulating glucose.

PubMed

Jandrain, B J; Pallikarakis, N; Normand, S; Pirnay, F; Lacroix, M; Mosora, F; Pachiaudi, C; Gautier, J F; Scheen, A J; Riou, J P

1993-05-01

The aim of the present study was to compare the metabolic fate of repeated doses of fructose or glucose ingested every 30 min during long-duration moderate-intensity exercise in men. Healthy volunteers exercised for 3 h on a treadmill at 45% of their maximal oxygen consumption rate. "Naturally labeled" [13C]glucose or [13C]fructose was given orally at 25-g doses every 30 min (total feeding: 150 g; n = 6 in each group). Substrate utilization was evaluated by indirect calorimetry, and exogenous sugar oxidation was measured by isotope ratio mass spectrometry on expired CO2. Results were corrected for baseline drift in 13C/12C ratio in expired air due to exercise alone. Fructose conversion to plasma glucose was measured combining gas chromatography and isotope ratio mass spectrometry. Most of the ingested glucose was oxidized: 81 +/- 4 vs. 57 +/- 2 g/3 h for fructose (2P < 0.005). Exogenous glucose covered 20.8 +/- 1.4% of the total energy need (+/- 6.7 MJ) compared with 14.0 +/- 0.6% for fructose (2P < 0.005). The contribution of total carbohydrates was significantly higher and that of lipids significantly lower with glucose than with fructose. The blood glucose response was similar in both protocols. From 90 to 180 min, 55-60% of circulating glucose was derived from ingested fructose. In conclusion, when ingested repeatedly during moderate-intensity prolonged exercise, fructose is metabolically less available than glucose, despite a high rate of conversion to circulating glucose.

Alteration of the Alkaloid Profile in Genetically Modified Tobacco Reveals a Role of Methylenetetrahydrofolate Reductase in Nicotine N-Demethylation1[C][W][OA

PubMed Central

Hung, Chiu-Yueh; Fan, Longjiang; Kittur, Farooqahmed S.; Sun, Kehan; Qiu, Jie; Tang, She; Holliday, Bronwyn M.; Xiao, Bingguang; Burkey, Kent O.; Bush, Lowell P.; Conkling, Mark A.; Roje, Sanja; Xie, Jiahua

2013-01-01

Methylenetetrahydrofolate reductase (MTHFR) is a key enzyme of the tetrahydrofolate (THF)-mediated one-carbon (C1) metabolic network. This enzyme catalyzes the reduction of 5,10-methylene-THF to 5-methyl-THF. The latter donates its methyl group to homocysteine, forming methionine, which is then used for the synthesis of S-adenosyl-methionine, a universal methyl donor for numerous methylation reactions, to produce primary and secondary metabolites. Here, we demonstrate that manipulating tobacco (Nicotiana tabacum) MTHFR gene (NtMTHFR1) expression dramatically alters the alkaloid profile in transgenic tobacco plants by negatively regulating the expression of a secondary metabolic pathway nicotine N-demethylase gene, CYP82E4. Quantitative real-time polymerase chain reaction and alkaloid analyses revealed that reducing NtMTHFR expression by RNA interference dramatically induced CYP82E4 expression, resulting in higher nicotine-to-nornicotine conversion rates. Conversely, overexpressing NtMTHFR1 suppressed CYP82E4 expression, leading to lower nicotine-to-nornicotine conversion rates. However, the reduced expression of NtMTHFR did not affect the methionine and S-adenosyl-methionine levels in the knockdown lines. Our finding reveals a new regulatory role of NtMTHFR1 in nicotine N-demethylation and suggests that the negative regulation of CYP82E4 expression may serve to recruit methyl groups from nicotine into the C1 pool under C1-deficient conditions. PMID:23221678

Investigation of operating parameters on CO2 splitting by dielectric barrier discharge plasma

NASA Astrophysics Data System (ADS)

Pan, CHEN; Jun, SHEN; Tangchun, RAN; Tao, YANG; Yongxiang, YIN

2017-12-01

Experiments of CO2 splitting by dielectric barrier discharge (DBD) plasma were carried out, and the influence of CO2 flow rate, plasma power, discharge voltage, discharge frequency on CO2 conversion and process energy efficiency were investigated. It was shown that the absolute quantity of CO2 decomposed was only proportional to the amount of conductive electrons across the discharge gap, and the electron amount was proportional to the discharge power; the energy efficiency of CO2 conversion was almost a constant at a lower level, which was limited by CO2 inherent discharge character that determined a constant gap electric field strength. This was the main reason why CO2 conversion rate decreased as the CO2 flow rate increase and process energy efficiency was decreased a little as applied frequency increased. Therefore, one can improve the CO2 conversion by less feed flow rate or larger discharge power in DBD plasma, but the energy efficiency is difficult to improve.

Detailed kinetics of titanium nitride synthesis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rode, H.; Hlavacek, V.

1995-02-01

A thermogravimetric analyzer is used to study the synthesis of TiN from Ti powder over a wide range of temperature, conversion and heating rate, and for two Ti precursor powders with different morphologies. Conversions to TiN up to 99% are obtained with negligible oxygen contamination. Nonisothermal initial rate and isothermal data are used in a nonlinear least-squares minimization to determine the most appropriate rate law. The logarithmic rate law offers an excellent agreement between the experimental and calculated conversions to TiN and can predict afterburning, which is an important experimentally observed phenomenon. Due to the form of the logarithmic ratemore » law, the observed activation energy is a function of effective particle size, extent of conversion, and temperature even when the intrinsic activation energy remains constant. This aspect explains discrepancies among activation energies obtained in previous studies. The frequently used sedimentation particle size is a poor measure of the powder reactivity. The BET surface area indicates the powder reactivity much better.« less

A 2D Microphysical Analysis of Aerosol Nucleation in the Polar Winter Stratosphere: Implications for H2SO4 Photolysis and Nucleation Mechanisms

NASA Technical Reports Server (NTRS)

Mills, Michael J.; Toon, Owen B.; Mills, Michael J.; Solomon, Susan

1997-01-01

Each spring a layer of small particles forms between 20 and 30 km in the polar regions. Results are presented from a 2D microphysical model of sulfate aerosol, which provide the first self-consistent explanation of the observed "CN layer." Photochemical conversion of sulfuric acid to SO2 in the upper stratosphere and mesosphere is necessary for this layer to form. Recent laboratory measurements of H2SO4 and SO3 photolysis rates are consistent with such conversion, though an additional source of SO2 may be required. Nucleation throughout the polar winter extends the top of the aerosol layer to higher altitudes, despite strong downward transport of ambient air. This finding may be important to heterogeneous chemistry at the top of the aerosol layer in polar winter and spring.

Experimental Study of Hydrogasification of Lignite and Subbituminous Coal Chars

PubMed Central

Gil, Stanisław

2015-01-01

The experimental facility for pressure hydrogasification research was adapted to the pressure of 10 MPa and temperature of 1300 K, which ensured repeatability of results and hydrogen heating to the process temperature. A hydrogasification reaction of chars produced from two rank coals was investigated at temperatures up to 1173 K, pressures up to 8 MPa, and the gas flow rates of 0.5–5 dmn 3/min. Reactivity of the “Szczerców” lignite char was found to be slightly higher than that of the subbituminous “Janina” coal char produced under the same conditions. A high value of the char reactivity was observed to a certain carbon conversion degree, above which a sharp drop took place. It was shown that, to achieve proper carbon conversion, the hydrogasification reaction must proceed at a temperature above 1200 K. PMID:26065028

The Kirkendall effect towards oxynitride nanotubes with improved visible light driven conversion of CO2 into CH4.

PubMed

Zhou, P; Gao, H L; Yan, S C; Zou, Z G

2016-02-28

Functional hollow nanomaterials are of great interest due to their unique physical-chemical properties. Oxynitride photocatalysts are a kind of promising material for solar energy conversion. However, nanoscale design of hollow oxynitrides was difficult to achieve due to the thermal instability of oxide precursors at high temperature. Here, single crystal zinc gallium oxynitride nanotubes were successfully synthesized via the Kirkendall effect with ZnO nanorods and Ga2O3 nanosheets as precursors, which can be attributed to the high diffusion rate of ZnO and the high melting point of oxynitride. Enhanced photocatalytic performance in CO2 reduction was achieved over the as-prepared ZnGaNO nanotubes, due to their higher specific surface area and less recombination of the photogenerated carriers. These results are expected to provide new guidance in the design and preparation of highly efficient nano-scaled oxynitride photocatalysts.

Consequences of Asexuality in Natural Populations: Insights from Stick Insects.

PubMed

Bast, Jens; Parker, Darren J; Dumas, Zoé; Jalvingh, Kirsten M; Tran Van, Patrick; Jaron, Kamil S; Figuet, Emeric; Brandt, Alexander; Galtier, Nicolas; Schwander, Tanja

2018-07-01

Recombination is a fundamental process with significant impacts on genome evolution. Predicted consequences of the loss of recombination include a reduced effectiveness of selection, changes in the amount of neutral polymorphisms segregating in populations, and an arrest of GC-biased gene conversion. Although these consequences are empirically well documented for nonrecombining genome portions, it remains largely unknown if they extend to the whole genome scale in asexual organisms. We identify the consequences of asexuality using de novo transcriptomes of five independently derived, obligately asexual lineages of stick insects, and their sexual sister-species. We find strong evidence for higher rates of deleterious mutation accumulation, lower levels of segregating polymorphisms and arrested GC-biased gene conversion in asexuals as compared with sexuals. Taken together, our study conclusively shows that predicted consequences of genome evolution under asexuality can indeed be found in natural populations.

A metal-free electrocatalyst for carbon dioxide reduction to multi-carbon hydrocarbons and oxygenates

NASA Astrophysics Data System (ADS)

Wu, Jingjie; Ma, Sichao; Sun, Jing; Gold, Jake I.; Tiwary, Chandrasekhar; Kim, Byoungsu; Zhu, Lingyang; Chopra, Nitin; Odeh, Ihab N.; Vajtai, Robert; Yu, Aaron Z.; Luo, Raymond; Lou, Jun; Ding, Guqiao; Kenis, Paul J. A.; Ajayan, Pulickel M.

2016-12-01

Electroreduction of carbon dioxide into higher-energy liquid fuels and chemicals is a promising but challenging renewable energy conversion technology. Among the electrocatalysts screened so far for carbon dioxide reduction, which includes metals, alloys, organometallics, layered materials and carbon nanostructures, only copper exhibits selectivity towards formation of hydrocarbons and multi-carbon oxygenates at fairly high efficiencies, whereas most others favour production of carbon monoxide or formate. Here we report that nanometre-size N-doped graphene quantum dots (NGQDs) catalyse the electrochemical reduction of carbon dioxide into multi-carbon hydrocarbons and oxygenates at high Faradaic efficiencies, high current densities and low overpotentials. The NGQDs show a high total Faradaic efficiency of carbon dioxide reduction of up to 90%, with selectivity for ethylene and ethanol conversions reaching 45%. The C2 and C3 product distribution and production rate for NGQD-catalysed carbon dioxide reduction is comparable to those obtained with copper nanoparticle-based electrocatalysts.

High repetition rate laser induced fluorescence applied to Surfatron Induced Plasmas

NASA Astrophysics Data System (ADS)

van der Mullen, J. J. A. M.; Palomares, J. M.; Carbone, E. A. D.; Graef, W.; Hübner, S.

2012-05-01

The reaction kinetics in the excitation space of Ar and the conversion space of Ar-molecule mixtures are explored using a combination of high rep-rate YAG-Dye laser systems with a well defined and easily controllable Surfatron Induced Plasma set-up. Applying the method of Saturation Time Resolved Laser Induced Fluorescence (SaTiRe-LIF), we could trace excitation and conversion channels and determine rates of electron and heavy particle excitation kinetics. The time resolved density disturbances observed in the Ar excitation space, which are initiated by the laser, reveal the excitation channels and corresponding rates; responses of the molecular radiation in Ar-molecule mixtures corresponds to the presence of conversion processes induced by heavy particle excitation kinetics.

Field trial of differential-phase-shift quantum key distribution using polarization independent frequency up-conversion detectors.

PubMed

Honjo, T; Yamamoto, S; Yamamoto, T; Kamada, H; Nishida, Y; Tadanaga, O; Asobe, M; Inoue, K

2007-11-26

We report a field trial of differential phase shift quantum key distribution (QKD) using polarization independent frequency up-conversion detectors. A frequency up-conversion detector is a promising device for achieving a high key generation rate when combined with a high clock rate QKD system. However, its polarization dependence prevents it from being applied to practical QKD systems. In this paper, we employ a modified polarization diversity configuration to eliminate the polarization dependence. Applying this method, we performed a long-term stability test using a 17.6-km installed fiber. We successfully demonstrated stable operation for 6 hours and achieved a sifted key generation rate of 120 kbps and an average quantum bit error rate of 3.14 %. The sifted key generation rate was not the estimated value but the effective value, which means that the sifted key was continuously generated at a rate of 120 kbps for 6 hours.

Highly Efficient Spin-to-Charge Current Conversion in Strained HgTe Surface States Protected by a HgCdTe Layer

NASA Astrophysics Data System (ADS)

Noel, P.; Thomas, C.; Fu, Y.; Vila, L.; Haas, B.; Jouneau, P.-H.; Gambarelli, S.; Meunier, T.; Ballet, P.; Attané, J. P.

2018-04-01

We report the observation of spin-to-charge current conversion in strained mercury telluride at room temperature, using spin pumping experiments. We show that a HgCdTe barrier can be used to protect the HgTe from direct contact with the ferromagnet, leading to very high conversion rates, with inverse Edelstein lengths up to 2.0 ±0.5 nm . The influence of the HgTe layer thickness on the conversion efficiency is found to differ strongly from what is expected in spin Hall effect systems. These measurements, associated with the temperature dependence of the resistivity, suggest that these high conversion rates are due to the spin momentum locking property of HgTe surface states.

CT Evaluation of the progression of hypoattenuating nodular lesions in virus-related chronic liver disease.

PubMed

Takayasu, Kenichi; Muramatsu, Yukio; Mizuguchi, Yasunori; Okusaka, Takuji; Shimada, Kazuaki; Takayama, Tadatoshi; Sakamoto, Michiie

2006-08-01

The purpose of this study was to clarify the natural outcomes of hypoattenuating nodular lesions in patients with virus-related chronic liver disease depicted on dynamic CT. Sixty lesions (mean size, 1.3 cm) exhibiting hypoattenuation or isoattenuation in the arterial and delayed phases of dynamic CT were retrospectively evaluated with additional CT (mean, six examinations) for a mean period of 838 days. The primary end point was emergence of hyperattenuating areas within hypoattenuating lesions, a phenomenon called attenuation conversion. Cumulative attenuation conversion rates suggesting rates of malignant transformation were calculated with the Kaplan-Meier method, and factors affecting attenuation conversion rate were analyzed with the Cox proportional hazard model. Thirty-six (60%) of 60 hypoattenuating lesions developed to hyperattenuating lesions, 21 were unchanged, and three disappeared spontaneously. The 36 lesions that became hyperattenuating were divided into two subgroups according to lesion enhancement pattern: hyper-in-hypoattenuating (n = 25) and entirely hyperattenuating (n = 11). The cumulative attenuation conversion rates for the 60 hypoattenuating lesions were 15.8%, 44.3%, and 58.7% at 1, 2, and 3 years. The hyper-in-hypoattenuating lesions showed more rapid progression to entirely enhanced lesions. Positive results for hepatitis C viral antibody (p = 0.028) and initial lesion size (p = 0.007) showed a positive correlation with attenuation conversion rate. Hypoattenuating hepatic nodular lesions in chronic liver disease depicted on dynamic CT have high malignant potential and should be followed with special attention to conversion from hypoattenuation to hyperattenuation to determine the optimal timing of treatment.

Estimation of the Adenoma Detection Rate From the Polyp Detection Rate by Using a Conversion Factor in a Predominantly Hispanic Population.

PubMed

Elhanafi, Sherif; Ortiz, Arleen M; Yarlagadda, Anita; Tsai, Cindy; Eloliby, Mohamed; Mallawaarachchi, Indika; Dwivedi, Alok; Zuckerman, Marc J; Othman, Mohamed O

2015-08-01

Calculating the adenoma detection rate (ADR) is a complex process in contrast to the polyp detection rate (PDR) that can be easily calculated. The average adenoma to polyp detection rate quotient (APDRQ) was proposed as a conversion factor to estimate the ADR for individual endoscopists from the endoscopist's PDR. However, this conversion factor was not validated in different practice settings. To validate the use of the proposed conversion factor in a practice setting with a predominantly Hispanic population. We conducted a retrospective, cross-sectional study (December 2007 to November 2012) of screening colonoscopies at a university practice setting with an 86.9% Hispanic population. The actual ADR and PDR were calculated for all endoscopists. The weighted average of ADR to PDR ratio for each endoscopist was used to obtain APDRQ. The APDRQ was used as a conversion multiplier to estimate each endoscopist's ADR using the single endoscopist's PDR. A total of 2148 screening colonoscopies were included. The average PDR for the whole group was 36.9% (range, 11% to 49%). The actual ADR was estimated as 25.5% (range, 11% to 37%). The average APDRQ for our group was 0.68. The estimated ADR was 25.48% (range, 8% to 33%). There was a high correlation between actual ADR and the estimated ADR (Pearson correlation=0.92). In a practice setting with a predominantly Hispanic population, a conversion factor can be used to estimate ADR from PDR providing a high degree of correlation with the actual ADR.

Design of hybrid nanoheterostructure systems for enhanced quantum and solar conversion efficiencies in dye-sensitized solar cells

NASA Astrophysics Data System (ADS)

Kılıç, Bayram; Telli, Hakan; Tüzemen, Sebahattin; Başaran, Ali; Pirge, Gursev

2015-04-01

Dye sensitized solar cells (DSSCs) with an innovative design involving controlled-morphology vertically aligned (VA) ZnO nanowires within mesoporous TiO2 structures with ultrahigh surface area for implementation as photoanodes are herein reported. Although TiO2 nanostructures exhibit excellent power conversion efficiency, the electron transport rate is low owing to low electron mobility. To overcome this, ZnO nanowires with high electron mobility have been investigated as potential candidates for photoanodes. However, the power conversion efficiency of ZnO nanowires is still lower than that of TiO2 owing to their low internal surface area. Consequently, in this work, vertical growth of ZnO nanowires within mesoporous TiO2 structures is carried out to increase their solar power conversion efficiency. The photovoltaic performance of solar cells using ZnO nanowires, mesoporous TiO2, and TiO2/ZnO hybrid structures are compared. The VA TiO2/ZnO hybrid structures are found to provide direct electron transfer compared with the tortuous pathway of zero-dimensional nanostructures, resulting in an increased conversion efficiency. It is demonstrated that the light scattering of the photoanode film is increased and electron recombination is decreased when an appropriate amount of mesoporous TiO2 is used as a substrate for ZnO nanowires. The DSSC fabricated with the TiO2/ZnO hybrid photoanode prepared with 15.8 wt. % TiO2 showed the highest conversion efficiency of 7.30%, approximately 5%, 18%, and 40% higher than that of DSSCs fabricated with 3.99 wt. % TiO2, pure TiO2, and pure ZnO photoanodes, respectively.

Influence of the anisotropy on the performance of D-band SiC IMPATT diodes

NASA Astrophysics Data System (ADS)

Chen, Qing; Yang, Lin'an; Wang, Shulong; Zhang, Yue; Dai, Yang; Hao, Yue

2015-03-01

Numerical simulation has been made to predict the RF performance of <0001> direction and <> direction p+/n/n-/n+ (single drift region) 4H silicon carbide (4H-SiC) impact-ionization-avalanche-transit-time (IMPATT) diodes for operation at D-band frequencies. We observed that the output performance of 4H-SiC IMPATT diode is sensitive to the crystal direction of the one-dimensional current flow. The simulation results show that <0001> direction 4H-SiC IMPATT diode provides larger breakdown voltage for its lower electron and hole ionization rates and higher dc-to-rf conversion efficiency (η) for its higher ratio of drift zone voltage drop (VD) to breakdown voltage (VB) compared with those for <> direction 4H-SiC IMPATT diode, which lead to higher-millimeter-wave power output for <0001> direction 4H-SiC IMPATT compared to <> direction. However, the quality factor Q for the <> direction 4H-SiC IMPATT diode is lower than that of <0001> direction, which implies that the <> direction 4H-SiC IMPATT diode exhibits better stability and higher growth rate of microwave oscillation compared with <0001> direction 4H-SiC IMPATT diode.

Comparison of catalytic converter performance in internal combustion engine fueled with Ron 95 and Ron 97 gasoline

NASA Astrophysics Data System (ADS)

Leman, A. M.; Rahman, Fakhrurrazi; Jajuli, Afiqah; Feriyanto, Dafit; Zakaria, Supaat

2017-09-01

Generating ideal stability between engine performance, fuel consumption and emission is one of the main challenges in the automotive industry. The characteristics of engine combustion and creation of emission might simply change with different types of operating parameters. This study aims in investigating the relationship between two types of fuels on the performance and exhaust emission of internal combustion engine using ceramic and metallic catalytic converters. Experimental tests were performed on Mitsubishi 4G93 engine by applying several ranges of engine speeds to determine the conversion of pollutant gases released by the engine. The obtained results specify that the usage of RON 97 equipped with metallic converters might increase the conversion percentage of 1.31% for CO and 126 ppm of HC gases. The metallic converters can perform higher conversion compared to ceramic because in the high space velocities, metallic has higher surface geometry area and higher amount of transverse Peclet number (Pi). Ceramic converters achieved conversion at 2496 ppm of NOx gas, which is higher than the metallic converter.

Prevalence of Enterobius vermicularis among Preschool Children in Muan-gun, Jeollanam-do, Korea

PubMed Central

Hong, Sung-Hee; Jeong, Young-Il; Lee, Jin-Hee; Cho, Shin-Hyeong; Lee, Won-Ja

2012-01-01

We assessed the prevalence of Enterobius vermicularis infection and changes in the egg positive rate (EPR) over 1-year time, using the adhesive cellophane-tape perianal swab method in 2,347 preschool children in Muan-gun, Jeollanam-do, Republic of Korea in 2008 and 2009. The overall EPR for E. vermicularis was 4.1% in 2008 and 4.5% in 2009. A study population of 389 children was repeatedly examined for 2 years. Within this group, the EPR in 2009 was twice higher than in 2008, and the EPR of the group of 5-7-year-old children was significantly higher than that of other age groups. Moreover, in the group of 5-7-year-old children in 2009, the rates of positive and negative conversion were significantly higher and lower, respectively, than in other age groups. Conclusively, enterobiasis was prevalent during 2008-2009 among preschool children in Muan-gun, Jeollanam-do, and the increased EPR in 2009 was due to an increase in newly acquired infections among 5-7-year-old children. PMID:22949757

Prevalence of Enterobius vermicularis among preschool children in Muan-gun, Jeollanam-do, Korea.

PubMed

Hong, Sung-Hee; Jeong, Young-Il; Lee, Jin-Hee; Cho, Shin-Hyeong; Lee, Won-Ja; Lee, Sang-Eun

2012-09-01

We assessed the prevalence of Enterobius vermicularis infection and changes in the egg positive rate (EPR) over 1-year time, using the adhesive cellophane-tape perianal swab method in 2,347 preschool children in Muan-gun, Jeollanam-do, Republic of Korea in 2008 and 2009. The overall EPR for E. vermicularis was 4.1% in 2008 and 4.5% in 2009. A study population of 389 children was repeatedly examined for 2 years. Within this group, the EPR in 2009 was twice higher than in 2008, and the EPR of the group of 5-7-year-old children was significantly higher than that of other age groups. Moreover, in the group of 5-7-year-old children in 2009, the rates of positive and negative conversion were significantly higher and lower, respectively, than in other age groups. Conclusively, enterobiasis was prevalent during 2008-2009 among preschool children in Muan-gun, Jeollanam-do, and the increased EPR in 2009 was due to an increase in newly acquired infections among 5-7-year-old children.

A cure-rate model for the Shuttle filament-wound case

NASA Technical Reports Server (NTRS)

Cagliostro, D. E.; Islas, A.; Hsu, Ming-Ta

1987-01-01

An epoxy and carbon fiber composite has been used to produce a light-weight rocket case for the Space Shuttle. A kinetic model is developed which can predict the extent of epoxy conversion during the winding and curing of the case. The model accounts for both chemical and physical kinetics. In the model, chemical kinetics occur exclusively up to the time the transition temperature equals the reaction temperature. At this point the resin begins to solidify and the rate of this process limits the rate of epoxy conversion. A comparison of predicted and actual epoxy conversion is presented for isothermal and temperature programmed cure schedules.

Methane Conversion to Ethylene and Aromatics on PtSn Catalysts

DOE PAGES

Gerceker, Duygu; Motagamwala, Ali Hussain; Rivera-Dones, Keishla R.; ...

2017-02-03

Pt and PtSn catalysts supported on SiO 2 and H-ZSM-5 were studied for methane conversion under nonoxidative conditions. Addition of Sn to Pt/SiO 2 increased the turnover frequency for production of ethylene by a factor of 3, and pretreatment of the catalyst at 1123 K reduced the extent of coke formation. Pt and PtSn catalysts supported on H-ZSM-5 zeolite were prepared to improve the activity and selectivity to non-coke products. Ethylene formation rates were 20 times faster over a PtSn(1:3)/H-ZSM-5 catalyst with SiO 2:Al 2O 3 = 280 in comparison to those over PtSn(3:1)/SiO 2. H-ZSM-5-supported catalysts were also activemore » for the formation of aromatics, and the rates of benzene and naphthalene formation were increased by using more acidic H-ZSM-5 supports. These catalysts operate through a bifunctional mechanism, in which ethylene is first produced on highly dispersed PtSn nanoparticles and then is subsequently converted to benzene and naphthalene on Brønsted acid sites within the zeolite support. The most active and stable PtSn catalyst forms carbon products at a rate, 2.5 mmol of C/((mol of Pt) s), which is comparable to that of state-of-the-art Mo/H-ZSM-5 catalysts with same metal loading operated under similar conditions (1.8 mmol of C/((mol of Mo) s)). Scanning transmission electron microscopy measurements suggest the presence of smaller Pt nanoparticles on H-ZSM-5-supported catalysts, in comparison to SiO 2-supported catalysts, as a possible source of their high activity. As a result, a microkinetic model of methane conversion on Pt and PtSn surfaces, built using results from density functional theory calculations, predicts higher coupling rates on bimetallic and stepped surfaces, supporting the experimental observations that relate the high catalytic activity to small PtSn particles.« less

Comparison of effects produced by nicotine and the α4β2-selective agonist 5-I-A-85380 on intracranial self-stimulation in rats.

PubMed

Freitas, Kelen; Carroll, F Ivy; Negus, S Stevens

2016-02-01

Intracranial self-stimulation (ICSS) is one type of preclinical procedure for research on pharmacological mechanisms that mediate abuse potential of drugs acting at various targets, including nicotinic acetylcholine receptors (nAChRs). This study compared effects of the nonselective nAChR agonist nicotine (0.032-1.0 mg/kg) and the α4β2-selective nAChR agonist 5-I-A-85380 (0.01-1.0 mg/kg) on ICSS in male Sprague-Dawley rats. Rats were implanted with electrodes targeting the medial forebrain bundle at the level of the lateral hypothalamus and trained to respond under a fixed-ratio 1 schedule for a range of brain stimulation frequencies (158-56 Hz). A broad range of 5-I-A-85380 doses produced an abuse-related increase (or "facilitation") of low ICSS rates maintained by low brain-stimulation frequencies, and this effect was blocked by both the nonselective nAChR antagonist mecamylamine and the selective α4β2 antagonist dihyrdo-β-erythroidine (DHβE). Conversely, nicotine produced weaker ICSS facilitation across a narrower range of doses, and higher nicotine doses decreased high rates of ICSS maintained by high brain-stimulation frequencies. The rate-decreasing effects of a high nicotine dose were blocked by mecamylamine but not DHβE. Chronic nicotine treatment produced selective tolerance to rate-decreasing effects of nicotine but did not alter ICSS rate-increasing effects of nicotine. These results suggest that α4β2 receptors are sufficient to mediate abuse-related rate-increasing effects of nAChR agonists in this ICSS procedure. Conversely, nicotine effects at non-α4β2 nAChRs appear to oppose and limit abuse-related effects mediated by α4β2 receptors, although tolerance can develop to these non-α4β2 effects. Selective α4β2 agonists may have higher abuse potential than nicotine. PsycINFO Database Record (c) 2016 APA, all rights reserved.

Joint DoD versus Navy Specific Lead Generation Advertising: Comparison of Conversion Rates to Quality Enlistments and Marginal Costs.

DTIC Science & Technology

1984-09-01

7D-Rt46 982 JOINT DOD VERSUS NAVY SPECIFIC LEAD GENERATION j/j ADVERTISING : COMPARISON OF..(U) J B FUGUR SCHOOL OF N BUSINESS DURHAM NC R C MOREY...REPORT I PEPIO0 COV9cO JOINT DOD VERSUS NAVY SPECIFIC LEAD GENERATION Technical Report ADVERTISING : Comparison of Conversion Rates to (0 Quality...block number) . Upper-Mental, High School Degree, enlistment contracts, national leads, Z Joint DOD advertising , Service Specific Advertising , conversion

Monitoring Enzymatic Reactions in Real Time Using Venturi Easy Ambient Sonic-Spray Ionization Mass Spectrometry

PubMed Central

2016-01-01

We developed a technique to monitor spatially confined surface reactions with mass spectrometry under ambient conditions, without the need for voltage or organic solvents. Fused-silica capillaries immersed in an aqueous solution, positioned in close proximity to each other and the functionalized surface, created a laminar flow junction with a resulting reaction volume of ∼5 pL. The setup was operated with a syringe pump, delivering reagents to the surface through a fused-silica capillary. The other fused-silica capillary was connected to a Venturi easy ambient sonic-spray ionization source, sampling the resulting analytes at a slightly higher flow rate compared to the feeding capillary. The combined effects of the inflow and outflow maintains a chemical microenvironment, where the rate of advective transport overcomes diffusion. We show proof-of-concept where acetylcholinesterase was immobilized on an organosiloxane polymer through electrostatic interactions. The hydrolysis of acetylcholine by acetylcholinesterase into choline was monitored in real-time for a range of acetylcholine concentrations, fused-silica capillary geometries, and operating flow rates. Higher reaction rates and conversion yields were observed with increasing acetylcholine concentrations, as would be expected. PMID:27249533

Irony and proverb comprehension in schizophrenia: do female patients "dislike" ironic remarks?

PubMed

Rapp, Alexander M; Langohr, Karin; Mutschler, Dorothee E; Wild, Barbara

2014-01-01

Difficulties in understanding irony and sarcasm are part of the social cognition deficits in patients with schizophrenia. A number of studies have reported higher error rates during comprehension in patients with schizophrenia. However, the relationships of these impairments to schizotypal personality traits and other language deficits, such as the comprehension of proverbs, are unclear. We investigated irony and proverb comprehension in an all-female sample of 20 schizophrenia patients and 27 matched controls. Subjects indicated if a statement was intended to be ironic, literal, or meaningless and furthermore rated the meanness and funniness of the stimuli and certainty of their decision. Patients made significantly more errors than controls did. Globally, there were no overall differences in the ratings. However, patients rated the subgroup of stimuli with answers given incorrectly as having significantly less meanness and in case of an error indicated a significantly higher certainty than controls. Across all of the study participants, performances in irony (r = -0.51) and proverb (r = 0.56) comprehension were significantly correlated with schizotypal personality traits, suggesting a continuum of nonliteral language understanding. Because irony is so frequent in everyday conversations, this makes irony an especially promising candidate for social cognition training in schizophrenia.

Reduction and conversion of 2,4,6-trinitrotoluene (TNT) by sulfide under simulated anaerobic conditions.

PubMed

Qiao, Hua; Wang, He-ling; Feng, Hua-jun; Yao, Jun; Shen, Dong-sheng; Tang, Zhi-jian

2010-07-15

To account for the fast disappearance of TNT in anaerobic fermentative liquid, we investigated TNT (TNT(0)=50 mg/L) reduction by Na(2)S at 30+/-1 degrees C in two types of buffer systems, a phosphate buffer (PB, system A) and a CH(3)COOH-NaHCO(3) buffer (system B). The effects of pH, sulfide concentration and buffer system on the conversion and reaction rate of TNT were investigated. The effect of different variables on the conversion of TNT decreased in the following order: Na(2)S concentration>pH>buffer system. A kinetics study showed that TNT reduction by Na(2)S occurred in two stages separated by a change point. The observed rate constants of the first stage K(obs-1) were 1 order of magnitude lower than those of the second stage. The TNT conversion rate increased and the time to reach the change point became shorter with increasing Na(2)S concentration and pH. A 5-fold increase in Na(2)S concentration above the theoretical stoichiometric concentration was optimum. Observed rate constants of the first stage K(obs-1) were proportional to the hydrosulfide ion concentration and the conversion rate of TNT was greater and faster in buffer system B than in system A. 2010 Elsevier B.V. All rights reserved.

The quality study of recycled glass phosphor waste for LED

NASA Astrophysics Data System (ADS)

Tsai, Chun-Chin; Chen, Guan-Hao; Yue, Cheng-Feng; Chen, Cin-Fu; Cheng, Wood-Hi

2017-02-01

To study the feasibility and quality of recycled glass phosphor waste for LED packaging, the experiments were conducted to compare optical characteristics between fresh color conversion layer and that made of recycled waste. The fresh color conversion layer was fabricated through sintering pristine mixture of Y.A.G. powder [yellow phosphor (Y3AlO12 : Ce3+). Those recycled waste glass phosphor re-melted to form Secondary Molten Glass Phosphor (S.M.G.P.). The experiments on such low melting temperature glass results showed that transmission rates of S.M.G.P. are 9% higher than those of first-sintered glass phosphor, corresponding to 1.25% greater average bubble size and 36% more bubble coverage area in S.M.G.P. In the recent years, high power LED modules and laser projectors have been requiring higher thermal stability by using glass phosphor materials for light mixing. Nevertheless, phosphor and related materials are too expensive to expand their markets. It seems a right trend and research goal that recycling such waste of high thermal stability and quality materials could be preferably one of feasible cost-down solutions. This technical approach could bring out brighter future for solid lighting and light source module industries.

System Evaluation and Economic Analysis of a HTGR Powered High-Temperature Electrolysis Hydrogen Production Plant

DOE Office of Scientific and Technical Information (OSTI.GOV)

Michael G. McKellar; Edwin A. Harvego; Anastasia A. Gandrik

2010-10-01

A design for a commercial-scale high-temperature electrolysis (HTE) plant for hydrogen production has been developed. The HTE plant is powered by a high-temperature gas-cooled reactor (HTGR) whose configuration and operating conditions are based on the latest design parameters planned for the Next Generation Nuclear Plant (NGNP). The current HTGR reference design specifies a reactor power of 600 MWt, with a primary system pressure of 7.0 MPa, and reactor inlet and outlet fluid temperatures of 322°C and 750°C, respectively. The power conversion unit will be a Rankine steam cycle with a power conversion efficiency of 40%. The reference hydrogen production plantmore » operates at a system pressure of 5.0 MPa, and utilizes a steam-sweep system to remove the excess oxygen that is evolved on the anode (oxygen) side of the electrolyzer. The overall system thermal-to-hydrogen production efficiency (based on the higher heating value of the produced hydrogen) is 40.4% at a hydrogen production rate of 1.75 kg/s and an oxygen production rate of 13.8 kg/s. An economic analysis of this plant was performed with realistic financial and cost estimating assumptions. The results of the economic analysis demonstrated that the HTE hydrogen production plant driven by a high-temperature helium-cooled nuclear power plant can deliver hydrogen at a cost of $3.67/kg of hydrogen assuming an internal rate of return, IRR, of 12% and a debt to equity ratio of 80%/20%. A second analysis shows that if the power cycle efficiency increases to 44.4%, the hydrogen production efficiency increases to 42.8% and the hydrogen and oxygen production rates are 1.85 kg/s and 14.6 kg/s respectively. At the higher power cycle efficiency and an IRR of 12% the cost of hydrogen production is $3.50/kg.« less

Student self-reported communication skills, knowledge and confidence across standardised patient, virtual and traditional clinical learning environments.

PubMed

Quail, Michelle; Brundage, Shelley B; Spitalnick, Josh; Allen, Peter J; Beilby, Janet

2016-02-27

Advanced communication skills are vital for allied health professionals, yet students often have limited opportunities in which to develop them. The option of increasing clinical placement hours is unsustainable in a climate of constrained budgets, limited placement availability and increasing student numbers. Consequently, many educators are considering the potentials of alternative training methods, such as simulation. Simulations provide safe, repeatable and standardised learning environments in which students can practice a variety of clinical skills. This study investigated students' self-rated communication skill, knowledge, confidence and empathy across simulated and traditional learning environments. Undergraduate speech pathology students were randomly allocated to one of three communication partners with whom they engaged conversationally for up to 30 min: a patient in a nursing home (n = 21); an elderly trained patient actor (n = 22); or a virtual patient (n = 19). One week prior to, and again following the conversational interaction, participants completed measures of self-reported communication skill, knowledge and confidence (developed by the authors based on the Four Habit Coding Scheme), as well as the Jefferson Scale of Empathy - Health Professionals (student version). All three groups reported significantly higher communication knowledge, skills and confidence post-placement (Median d = .58), while the degree of change did not vary as a function of group membership (Median η (2)  < .01). In addition, only students interacting with a nursing home resident reported higher empathy after the placement. Students reported that conversing with the virtual patient was more challenging than conversing with a nursing home patient or actor, and students appeared to derive the same benefit from the experience. Participants self-reported higher communication skill, knowledge and confidence, though not empathy, following a brief placement in a virtual, standardised or traditional learning environment. The self-reported increases were consistent across the three placement types. It is proposed that the findings from this study provide support for the integration of more sustainable, standardised, virtual patient-based placement models into allied health training programs for the training of communication skills.

Equipoise among recanalization strategies.

PubMed

Tomsick, T A; Khatri, P; Jovin, T; Demaerschalk, B; Malisch, T; Demchuk, A; Hill, M D; Jauch, E; Spilker, J; Broderick, J P

2010-03-30

Modern acute ischemic stroke therapy is based on the premise that recanalization and subsequent reperfusion are essential for the preservation of brain tissue and favorable clinical outcomes. We outline key issues that we think underlie equipoise regarding the comparative clinical efficacy of IV recombinant tissue-type plasminogen activator (rt-PA) and intra-arterial (IA) reperfusion therapies for acute ischemic stroke. On the one hand, IV rt-PA therapy has the benefit of speed with presumed lower rates of recanalization of large artery occlusions as compared to IA methods. More recent reports of major arterial occlusions treated with IV rt-PA, as measured by transcranial Doppler and magnetic resonance angiography, demonstrate higher rates of recanalization. Conversely, IA therapies report higher recanalization rates, but are hampered by procedural delays and risks, even failing to be applied at all in occasional patients where time to reperfusion remains a critical factor. Higher rates of recanalization in IA trials using clot-removal devices have not translated into improved patient functional outcome as compared to trials of IV therapy. Combined IV-IA therapy promises to offer advantages of both, but perhaps only when applied in the timeliest of fashions, compared to IV therapy alone. Where equipoise exists, randomizing subjects to either IV rt-PA therapy or IV therapy followed by IA intervention, while incorporating new interventions into the study design, is a rational and appropriate research approach.

Forging property, processing map, and mesoscale microstructural evolution modeling of a Ti-17 alloy with a lamellar (α+β) starting microstructure

NASA Astrophysics Data System (ADS)

Matsumoto, Hiroaki; Naito, Daiki; Miyoshi, Kento; Yamanaka, Kenta; Chiba, Akihiko; Yamabe-Mitarai, Yoko

2017-12-01

This work identifies microstructural conversion mechanisms during hot deformation (at temperatures ranging from 750 °C to 1050 °C and strain rates ranging from 10-3 s-1 to 1 s-1) of a Ti-5Al-2Sn-2Zr-4Mo-4Cr (Ti-17) alloy with a lamellar starting microstructure and establishes constitutive formulae for predicting the microstructural evolution using finite-element analysis. In the α phase, lamellae kinking is the dominant mode in the higher strain rate region and dynamic globularization frequently occurs at higher temperatures. In the β phase, continuous dynamic recrystallization is the dominant mode below the transition temperature, Tβ (880 890 °C). Dynamic recovery tends to be more active at conditions of lower strain rates and higher temperatures. At temperatures above Tβ, continuous dynamic recrystallization of the β phase frequently occurs, especially in the lower strain rate region. A set of constitutive equations modeling the microstructural evolution and processing map characteristic are established by optimizing the experimental data and were later implemented in the DEFORM-3D software package. There is a satisfactory agreement between the experimental and simulated results, indicating that the established series of constitutive models can be used to reliably predict the properties of a Ti-17 alloy after forging in the (α+β) region.

Forging property, processing map, and mesoscale microstructural evolution modeling of a Ti-17 alloy with a lamellar (α+β) starting microstructure

PubMed Central

Matsumoto, Hiroaki; Naito, Daiki; Miyoshi, Kento; Yamanaka, Kenta; Chiba, Akihiko; Yamabe-Mitarai, Yoko

2017-01-01

Abstract This work identifies microstructural conversion mechanisms during hot deformation (at temperatures ranging from 750 °C to 1050 °C and strain rates ranging from 10−3 s−1 to 1 s−1) of a Ti-5Al-2Sn-2Zr-4Mo-4Cr (Ti-17) alloy with a lamellar starting microstructure and establishes constitutive formulae for predicting the microstructural evolution using finite-element analysis. In the α phase, lamellae kinking is the dominant mode in the higher strain rate region and dynamic globularization frequently occurs at higher temperatures. In the β phase, continuous dynamic recrystallization is the dominant mode below the transition temperature, T β (880~890 °C). Dynamic recovery tends to be more active at conditions of lower strain rates and higher temperatures. At temperatures above T β, continuous dynamic recrystallization of the β phase frequently occurs, especially in the lower strain rate region. A set of constitutive equations modeling the microstructural evolution and processing map characteristic are established by optimizing the experimental data and were later implemented in the DEFORM-3D software package. There is a satisfactory agreement between the experimental and simulated results, indicating that the established series of constitutive models can be used to reliably predict the properties of a Ti-17 alloy after forging in the (α+β) region. PMID:29152021

Forging property, processing map, and mesoscale microstructural evolution modeling of a Ti-17 alloy with a lamellar (α+β) starting microstructure.

PubMed

Matsumoto, Hiroaki; Naito, Daiki; Miyoshi, Kento; Yamanaka, Kenta; Chiba, Akihiko; Yamabe-Mitarai, Yoko

2017-01-01

This work identifies microstructural conversion mechanisms during hot deformation (at temperatures ranging from 750 °C to 1050 °C and strain rates ranging from 10 -3  s -1 to 1 s -1 ) of a Ti-5Al-2Sn-2Zr-4Mo-4Cr (Ti-17) alloy with a lamellar starting microstructure and establishes constitutive formulae for predicting the microstructural evolution using finite-element analysis. In the α phase, lamellae kinking is the dominant mode in the higher strain rate region and dynamic globularization frequently occurs at higher temperatures. In the β phase, continuous dynamic recrystallization is the dominant mode below the transition temperature, T β (880~890 °C). Dynamic recovery tends to be more active at conditions of lower strain rates and higher temperatures. At temperatures above T β , continuous dynamic recrystallization of the β phase frequently occurs, especially in the lower strain rate region. A set of constitutive equations modeling the microstructural evolution and processing map characteristic are established by optimizing the experimental data and were later implemented in the DEFORM-3D software package. There is a satisfactory agreement between the experimental and simulated results, indicating that the established series of constitutive models can be used to reliably predict the properties of a Ti-17 alloy after forging in the (α+ β ) region.

Effect of borate glass composition on its conversion to hydroxyapatite and on the proliferation of MC3T3-E1 cells.

PubMed

Brown, Roger F; Rahaman, Mohamed N; Dwilewicz, Agatha B; Huang, Wenhai; Day, Delbert E; Li, Yadong; Bal, B Sonny

2009-02-01

Glasses containing varying amounts of B(2)O(3) were prepared by partially or fully replacing the SiO(2) in silicate 45S5 bioactive glass with B(2)O(3). The effects of the B(2)O(3) content of the glass on its conversion to hydroxyapatite (HA) and on the proliferation of MC3T3-E1 cells were investigated in vitro. Conversion of the glasses to HA in dilute (20 mM) K(2)HPO(4) solution was monitored using weight loss and pH measurements. Proliferation of MC3T3-E1 cells was determined qualitatively by assay of cell density at the glass interface after incubation for 1 day and 3 days, and quantitatively by fluorescent measurements of total DNA in cultures incubated for 4 days. Higher B(2)O(3) content of the glass increased the conversion rate to HA, but also resulted in a greater inhibition of cell proliferation under static culture conditions. For a given mass of glass in the culture medium, the inhibition of cell proliferation was alleviated by using glasses with lower B(2)O(3) content, by incubating the cell cultures under dynamic rather than static conditions, or by partially converting the glass to HA prior to cell culture.

A set of observational measures for rating support and participation in conversation between adults with aphasia and their conversation partners.

PubMed

Kagan, Aura; Winckel, Joanne; Black, Sandra; Duchan, Judith Felson; Simmons-Mackie, Nina; Square, Paula

2004-01-01

Conversation partners of individuals with aphasia, including health care professionals, families, and others, play a role that is as important for communication as the language disorder suffered by individuals with aphasia. Two complementary measures designed to capture elements of conversation between adults with aphasia and their speaking conversation partners have been developed. The first measure provides an index of the conversation partner's skill in providing conversational support. The second provides an index of the level of participation in conversation by the person with aphasia. This article describes the development of the measures, including preliminary psychometric data, and discusses applications.

RISK OF TUBERCULOUS INFECTION AND OF RADIATION AMONG UNIVERSITY STUDENTS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Szent-Gyoergyi, N.

1961-03-01

The student population of the University of Chicago was divided into general and special risk groups to assess the relative necessity of frequent x- ray examinations in the 2 groups. Positive tuberculin tests were detected in 5.9 and 32.5% of the 2 groups, respectively, and the conversion rate (to positive tests) was 0.9% for the general risk and 6.4% for the special risk groups. Thus, both positive tuberculin skin test and conversion rate were significantly higher among foreign-born, nonwhite, and medical students than among native white students. The findings indicate the necessity of more frequent skin testing and roentgenography inmore » the special risk group, thus permitting reduction of the radiation hazard and the cost of the tuberculosis control program in the largest part (80.9%) of university students without endangering the effectiveness of the program. In view of the findings of this study, it may be possible to further reduce the frequency of x-ray microfilming. After the initial skin test and microfilm, the skin test can be repeated in the special risk group yearly, but microfilms used only in positive skin-test cases. (H.H.D.)« less

A numerical analysis to evaluate Betz's Law for vertical axis wind turbines

NASA Astrophysics Data System (ADS)

Thönnißen, F.; Marnett, M.; Roidl, B.; Schröder, W.

2016-09-01

The upper limit for the energy conversion rate of horizontal axis wind turbines (HAWT) is known as the Betz limit. Often this limit is also applied to vertical axis wind turbines (VAWT). However, a literature review reveals that early analytical and recent numerical approaches predicted values for the maximum power output of VAWTs close to or even higher than the Betz limit. Thus, it can be questioned whether the application of Betz's Law to VAWTs is justified. To answer this question, the current approach combines a free vortex model with a 2D inviscid panel code to represent the flow field of a generic VAWT. To ensure the validity of the model, an active blade pitch control system is used to avoid flow separation. An optimal pitch curve avoiding flow separation is determined for one specific turbine configuration by applying an evolutionary algorithm. The analysis yields a net power output that is slightly (≈6%) above the Betz limit. Besides the numerical result of an increased energy conversion rate, especially the identification of two physical power increasing mechanisms shows, that the application of Betz's Law to VAWTs is not justified.

Defining SNAP by cross-sectional and longitudinal definitions of neurodegeneration.

PubMed

Wisse, L E M; Das, S R; Davatzikos, C; Dickerson, B C; Xie, S X; Yushkevich, P A; Wolk, D A

2018-01-01

Suspected non-Alzheimer's pathophysiology (SNAP) is a biomarker driven designation that represents a heterogeneous group in terms of etiology and prognosis. SNAP has only been identified by cross-sectional neurodegeneration measures, whereas longitudinal measures might better reflect "active" neurodegeneration and might be more tightly linked to prognosis. We compare neurodegeneration defined by cross-sectional 'hippocampal volume' only (SNAP/L-) versus both cross-sectional and longitudinal 'hippocampal atrophy rate' (SNAP/L+) and investigate how these definitions impact prevalence and the clinical and biomarker profile of SNAP in Mild Cognitive Impairment (MCI). 276 MCI patients from ADNI-GO/2 were designated amyloid "positive" (A+) or "negative" (A-) based on their florbetapir scan and neurodegeneration 'positive' or 'negative' based on cross-sectional hippocampal volume and longitudinal hippocampal atrophy rate. 74.1% of all SNAP participants defined by the cross-sectional definition of neurodegeneration also met the longitudinal definition of neurodegeneration, whereas 25.9% did not. SNAP/L+ displayed larger white matter hyperintensity volume, a higher conversion rate to dementia over 5 years and a steeper decline on cognitive tasks compared to SNAP/L- and the A- CN group. SNAP/L- had more abnormal values on neuroimaging markers and worse performance on cognitive tasks than the A- CN group, but did not show a difference in dementia conversion rate or longitudinal cognition. Using a longitudinal definition of neurodegeneration in addition to a cross-sectional one identifies SNAP participants with significant cognitive decline and a worse clinical prognosis for which cerebrovascular disease may be an important driver.

Selective oxidation of rhodinol to citral using H{sub 2}O{sub 2}-platinum black system under microwave irradiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chong, D. J. W.; Latip, J.; Hasbullah, S. A.

2014-09-03

The oxidation method utilising H{sub 2}O{sub 2}-Pt black system was successfully adapted in the oxidation of rhodinol which is a mixture form of geraniol and citronellol. This green oxidation found to be selectively converted geraniol to citral using conventional method. The implementation of microwave irradiation (175 Watt, 90°C, 30 mins) and a higher molar of H{sub 2}O{sub 2} further improved the conversion rate (72.6%) and selectivity (81%) as compared to the conventional method.

Selective oxidation of rhodinol to citral using H2O2-platinum black system under microwave irradiation

NASA Astrophysics Data System (ADS)

Chong, D. J. W.; Latip, J.; Hasbullah, S. A.; Sastrohamidjojo, H.

2014-09-01

The oxidation method utilising H2O2-Pt black system was successfully adapted in the oxidation of rhodinol which is a mixture form of geraniol and citronellol. This green oxidation found to be selectively converted geraniol to citral using conventional method. The implementation of microwave irradiation (175 Watt, 90°C, 30 mins) and a higher molar of H2O2 further improved the conversion rate (72.6%) and selectivity (81%) as compared to the conventional method.

Gasification of refinery sludge in an updraft reactor for syngas production

NASA Astrophysics Data System (ADS)

Ahmed, Reem; Sinnathambi, Chandra M.; Eldmerdash, Usama

2014-10-01

The study probes into the investigation on gasification of dry refinery sludge. The details of the study includes; influence of operation time, oxidation temperature and equivalence ratios on carbon gas conversion rate, gasification efficiency, heating value and fuel gas yield are presented. The results show that, the oxidation temperature increased sharply up to 858°C as the operating time increased up to 36 min then bridging occurred at 39 min which cause drop in reaction temperature up to 819 °C. This bridging was found to affect also the syngas compositions, meanwhile as the temperature decreased the CO, H2, CH4 compositions are also found to be decreases. Higher temperature catalyzed the reduction reaction (CO2+ C = 450 2CO ), and accelerated the carbon conversion and gasification efficiencies, resulted in more solid fuel is converted to a high heating value gas fuel. The equivalence ratio of 0.195 was found to be the optimum value for carbon conversion and cold gas efficiencies, high heating value of gas, and fuel gas yield to reach their maximum values of 96.1 % and 53.7 %, 5.42 MJ Nm-3 of, and 2.5 Nm3 kg-1 respectively.

High temperature gasification of high heating-rate chars using a flat-flame reactor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Tian; Niu, Yanqing; Wang, Liang

The increasing interest in gasification and oxy-fuel combustion of biomass has heightened the need for a detailed understanding of char gasification in industrially relevant environments (i.e., high temperature and high-heating rate). Despite innumerable studies previously conducted on gasification of biomass, very few have focused on such conditions. Consequently, in this study the high-temperature gasification behaviors of biomass-derived chars were investigated using non-intrusive techniques. Two biomass chars produced at a heating rate of approximately 10 4 K/s were subjected to two gasification environments and one oxidation environment in an entrained flow reactor equipped with an optical particle-sizing pyrometer. A coal charmore » produced from a common U.S. low sulfur subbituminous coal was also studied for comparison. Both char and surrounding gas temperatures were precisely measured along the centerline of the furnace. Despite differences in the physical and chemical properties of the biomass chars, they exhibited rather similar reaction temperatures under all investigated conditions. On the other hand, a slightly lower particle temperature was observed in the case of coal char gasification, suggesting a higher gasification reactivity for the coal char. A comprehensive numerical model was applied to aid the understanding of the conversion of the investigated chars under gasification atmospheres. In addition, a sensitivity analysis was performed on the influence of four parameters (gas temperature, char diameter, char density, and steam concentration) on the carbon conversion rate. Here, the results demonstrate that the gas temperature is the most important single variable influencing the gasification rate.« less

High temperature gasification of high heating-rate chars using a flat-flame reactor

DOE PAGES

Li, Tian; Niu, Yanqing; Wang, Liang; ...

2017-08-25

The increasing interest in gasification and oxy-fuel combustion of biomass has heightened the need for a detailed understanding of char gasification in industrially relevant environments (i.e., high temperature and high-heating rate). Despite innumerable studies previously conducted on gasification of biomass, very few have focused on such conditions. Consequently, in this study the high-temperature gasification behaviors of biomass-derived chars were investigated using non-intrusive techniques. Two biomass chars produced at a heating rate of approximately 10 4 K/s were subjected to two gasification environments and one oxidation environment in an entrained flow reactor equipped with an optical particle-sizing pyrometer. A coal charmore » produced from a common U.S. low sulfur subbituminous coal was also studied for comparison. Both char and surrounding gas temperatures were precisely measured along the centerline of the furnace. Despite differences in the physical and chemical properties of the biomass chars, they exhibited rather similar reaction temperatures under all investigated conditions. On the other hand, a slightly lower particle temperature was observed in the case of coal char gasification, suggesting a higher gasification reactivity for the coal char. A comprehensive numerical model was applied to aid the understanding of the conversion of the investigated chars under gasification atmospheres. In addition, a sensitivity analysis was performed on the influence of four parameters (gas temperature, char diameter, char density, and steam concentration) on the carbon conversion rate. Here, the results demonstrate that the gas temperature is the most important single variable influencing the gasification rate.« less

Xylose Isomerase Improves Growth and Ethanol Production Rates from Biomass Sugars for Both Saccharomyces Pastorianus and Saccharomyces Cerevisiae

PubMed Central

Miller, Kristen P.; Gowtham, Yogender Kumar; Henson, J. Michael; Harcum, Sarah W.

2013-01-01

The demand for biofuel ethanol made from clean, renewable nonfood sources is growing. Cellulosic biomass, such as switch grass (Panicum virgatum L.), is an alternative feedstock for ethanol production; however, cellulosic feedstock hydrolysates contain high levels of xylose, which needs to be converted to ethanol to meet economic feasibility. In this study, the effects of xylose isomerase on cell growth and ethanol production from biomass sugars representative of switch grass were investigated using low cell density cultures. The lager yeast species Saccharomyces pastorianus was grown with immobilized xylose isomerase in the fermentation step to determine the impact of the glucose and xylose concentrations on the ethanol production rates. Ethanol production rates were improved due to xylose isomerase; however, the positive effect was not due solely to the conversion of xylose to xylulose. Xylose isomerase also has glucose isomerase activity, so to better understand the impact of the xylose isomerase on S. pastorianus, growth and ethanol production were examined in cultures provided fructose as the sole carbon. It was observed that growth and ethanol production rates were higher for the fructose cultures with xylose isomerase even in the absence of xylose. To determine whether the positive effects of xylose isomerase extended to other yeast species, a side-by-side comparison of S. pastorianus and Saccharomyces cerevisiae was conducted. These comparisons demonstrated that the xylose isomerase increased ethanol productivity for both the yeast species by increasing the glucose consumption rate. These results suggest that xylose isomerase can contribute to improved ethanol productivity, even without significant xylose conversion. PMID:22866331

The Role of Race/Ethnicity in Alcohol-attributable Injury in the United States

PubMed Central

Keyes, Katherine M.; Liu, Xianfang C.; Cerda, Magdalena

2012-01-01

A substantial proportion of injuries worldwide are attributable to alcohol consumption, and US estimates indicate that the drinking patterns of racial/ethnic groups vary considerably. The authors reviewed evidence from 19 publications regarding racial/ethnic differences in overall alcohol-attributable injury as well as percent blood alcohol content positivity for injury deaths in the United States. They found that Native Americans evidence higher rates of alcohol-attributable motor vehicle crash fatality, suicide, and falls compared with other racial/ethnic groups; conversely, Asians evidence lower rates of alcohol-attributable injury than other racial/ethnic groups. The rate of alcohol positivity and intoxication among Hispanics is disproportionately high relative to estimates of alcohol use. Black subgroups also evidence higher rates of alcohol positivity than would be expected given estimates of alcohol use, including for alcohol positivity among drivers of fatally injured black children and homicide. These findings highlight the continued need for public health focus on Native American populations with respect to alcohol consumption and injury. Further, the disparity in alcohol-attributable injury mortality among black and Hispanic groups relative to their reported rates of alcohol consumption is an overlooked area of research. The authors review potential social determinants of racial/ethnic disparities in alcohol-attributable injuries and identify directions for further research on these patterns. PMID:21930592

The Role of Race/Ethnicity in Alcohol-attributable Injury in the United States

PubMed Central

Keyes, Katherine M.; Liu, Xianfang C.; Cerda, Magdalena

2017-01-01

A substantial proportion of injuries worldwide are attributable to alcohol consumption, and US estimates indicate that the drinking patterns of racial/ethnic groups vary considerably. The authors reviewed evidence from 19 publications regarding racial/ethnic differences in overall alcohol-attributable injury as well as percent blood alcohol content positivity for injury deaths in the United States. They found that Native Americans evidence higher rates of alcohol-attributable motor vehicle crash fatality, suicide, and falls compared with other racial/ethnic groups; conversely, Asians evidence lower rates of alcohol-attributable injury than other racial/ethnic groups. The rate of alcohol positivity and intoxication among Hispanics is disproportionately high relative to estimates of alcohol use. Black subgroups also evidence higher rates of alcohol positivity than would be expected given estimates of alcohol use, including for alcohol positivity among drivers of fatally injured black children and homicide. These findings highlight the continued need for public health focus on Native American populations with respect to alcohol consumption and injury. Further, the disparity in alcohol-attributable injury mortality among black and Hispanic groups relative to their reported rates of alcohol consumption is an overlooked area of research. The authors review potential social determinants of racial/ethnic disparities in alcohol-attributable injuries and identify directions for further research on these patterns. PMID:23441581

Determination of the Rate Coefficients of the SO2 plus O plus M yields SO3 plus M Reaction

NASA Technical Reports Server (NTRS)

Hwang, S. M.; Cooke, J. A.; De Witt, K. J.; Rabinowitz, M. J.

2010-01-01

Rate coefficients of the title reaction R(sub 31) (SO2 +O+M yields SO3 +M) and R(sub 56) (SO2 + HO2 yields SO3 +OH), important in the conversion of S(IV) to S(VI),were obtained at T =970-1150 K and rho (sub ave) = 16.2 micro mol/cubic cm behind reflected shock waves by a perturbation method. Shock-heated H2/ O2/Ar mixtures were perturbed by adding small amounts of SO2 (1%, 2%, and 3%) and the OH temporal profiles were then measured using laser absorption spectroscopy. Reaction rate coefficients were elucidated by matching the characteristic reaction times acquired from the individual experimental absorption profiles via simultaneous optimization of k(sub 31) and k(sub 56) values in the reaction modeling (for satisfactory matches to the observed characteristic times, it was necessary to take into account R(sub 56)). In the experimental conditions of this study, R(sub 31) is in the low-pressure limit. The rate coefficient expressions fitted using the combined data of this study and the previous experimental results are k(sub 31,0)/[Ar] = 2.9 10(exp 35) T(exp ?6.0) exp(?4780 K/T ) + 6.1 10(exp 24) T(exp ?3.0) exp(?1980 K/T ) cm(sup 6) mol(exp ?2)/ s at T = 300-2500 K; k(sub 56) = 1.36 10(exp 11) exp(?3420 K/T ) cm(exp 3)/mol/s at T = 970-1150 K. Computer simulations of typical aircraft engine environments, using the reaction mechanism with the above k(sub 31,0) and k(sub 56) expressions, gave the maximum S(IV) to S(VI) conversion yield of ca. 3.5% and 2.5% for the constant density and constant pressure flow condition, respectively. Moreover, maximum conversions occur at rather higher temperatures (?1200 K) than that where the maximum k(sub 31,0) value is located (approximately 800 K). This is because the conversion yield is dependent upon not only the k(sup 31,0) and k(sup 56) values (production flux) but also the availability of H, O, and HO2 in the system (consumption flux).

Conversion of Nuclear Waste to Molten Glass: Cold-Cap Reactions in Crucible Tests

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu, Kai; Hrma, Pavel; Rice, Jarrett A.

2016-05-23

The feed-to-glass conversion, which comprises complex chemical reactions and phase transitions, occurs in the cold-cap zone during nuclear waste vitrification. Knowledge of the chemistry and physics of feed-to-glass conversion will help us control the conversion path by changing the melter feed makeup to maximize the glass production rate. To investigate the conversion process, we analyzed heat-treated samples of a simulated high-level waste feed using X-ray diffraction, electron probe microanalysis – wavelength dispersive X-ray spectroscopy, leaching tests, and residual anion analysis. Feed dehydration, gas evolution, and borate phase formation occurred at temperatures below 700 °C before the emerging glass-forming melt wasmore » completely connected. Above 800 °C, intermediate aluminosilicate phases and quartz particles were gradually dissolving in the continuous borosilicate melt, which expanded into transient foam. Knowledge of the chemistry and physics of feed-to-glass conversion will help us control the conversion path by changing the melter feed makeup to maximize the glass production rate.« less

Quantitative Validation of the Presto Blue Metabolic Assay for Online Monitoring of Cell Proliferation in a 3D Perfusion Bioreactor System.

PubMed

Sonnaert, Maarten; Papantoniou, Ioannis; Luyten, Frank P; Schrooten, Jan Ir

2015-06-01

As the fields of tissue engineering and regenerative medicine mature toward clinical applications, the need for online monitoring both for quantitative and qualitative use becomes essential. Resazurin-based metabolic assays are frequently applied for determining cytotoxicity and have shown great potential for monitoring 3D bioreactor-facilitated cell culture. However, no quantitative correlation between the metabolic conversion rate of resazurin and cell number has been defined yet. In this work, we determined conversion rates of Presto Blue, a resazurin-based metabolic assay, for human periosteal cells during 2D and 3D static and 3D perfusion cultures. Our results showed that for the evaluated culture systems there is a quantitative correlation between the Presto Blue conversion rate and the cell number during the expansion phase with no influence of the perfusion-related parameters, that is, flow rate and shear stress. The correlation between the cell number and Presto Blue conversion subsequently enabled the definition of operating windows for optimal signal readouts. In conclusion, our data showed that the conversion of the resazurin-based Presto Blue metabolic assay can be used as a quantitative readout for online monitoring of cell proliferation in a 3D perfusion bioreactor system, although a system-specific validation is required.

Quantitative Validation of the Presto Blue™ Metabolic Assay for Online Monitoring of Cell Proliferation in a 3D Perfusion Bioreactor System

PubMed Central

Sonnaert, Maarten; Papantoniou, Ioannis; Luyten, Frank P.

2015-01-01

As the fields of tissue engineering and regenerative medicine mature toward clinical applications, the need for online monitoring both for quantitative and qualitative use becomes essential. Resazurin-based metabolic assays are frequently applied for determining cytotoxicity and have shown great potential for monitoring 3D bioreactor-facilitated cell culture. However, no quantitative correlation between the metabolic conversion rate of resazurin and cell number has been defined yet. In this work, we determined conversion rates of Presto Blue™, a resazurin-based metabolic assay, for human periosteal cells during 2D and 3D static and 3D perfusion cultures. Our results showed that for the evaluated culture systems there is a quantitative correlation between the Presto Blue conversion rate and the cell number during the expansion phase with no influence of the perfusion-related parameters, that is, flow rate and shear stress. The correlation between the cell number and Presto Blue conversion subsequently enabled the definition of operating windows for optimal signal readouts. In conclusion, our data showed that the conversion of the resazurin-based Presto Blue metabolic assay can be used as a quantitative readout for online monitoring of cell proliferation in a 3D perfusion bioreactor system, although a system-specific validation is required. PMID:25336207

Is Donor Service Area Market Competition Associated With Organ Procurement Organization Performance?

PubMed

Adler, Joel T; Yeh, Heidi; Markmann, James F; Axelrod, David A

2016-06-01

Organ procurement organizations (OPOs) are currently evaluated on donation rates and number of organs per donor. However, there is significant variability in market characteristics which affect transplant programs' donor organ acceptance practices and OPOs' ability to successfully place higher risk organs. The impact of transplant market characteristics on OPO performance metrics has not been evaluated. The OPO performance measures were correlated annually with the Herfindahl Hirschman Index, a standard measure of market competition for centers within the OPO donor service areas from 2003 to 2011. More competitive donor service areas were associated with increased number of donors (P = 0.01) and eligible deaths (P < 0.001). Market competition was associated with increased use of high Donor Risk Index for kidney (P = 0.03) and liver (P = 0.01) allografts. The OPOs with increased competition in liver transplant also were noted to have a higher donor conversion rate (P < 0.001), more donors per million population (P < 0.001), and a higher utilization rate for liver allografts (P = 0.007). These data suggest that proposals to increase district size to increase competition among transplant programs could result in improved organ utilization over time by incentivizing the use of marginal donor organs and increasing access to transplantation.

Experimental self-etching HEMA-free adhesive systems: cytotoxicity and degree of conversion.

PubMed

Barbosa, Marília Oliveira; de Carvalho, Rodrigo Varella; Demarco, Flávio Fernando; Ogliari, Fabrício Aulo; Zanchi, Cesar Henrique; Piva, Evandro; da Silva, Adriana Fernandes

2015-01-01

The aim of this study was to evaluate the effect of replacing 2-hydroxyethyl methacrylate (HEMA) by methacrylate surfactant monomers on the cytotoxicity and degree of conversion of two-step self-etching dentin adhesive systems. Five HEMA-free adhesive systems were tested: Bis-EMA 10, Bis-EMA 30, PEG400, PEG400UDMA, PEG1000, and a HEMA group was used as positive control. The cytotoxicity of the experimental primers, with different monomer concentrations (2 or 20 wt%), and bond resins, containing 25 wt% surfactant, was assessed using murine fibroblast cell line 3T3 and the tetrazolium assay (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT)). The degree of conversion of the bond resins was analyzed using Fourier transform infrared spectroscopy. The data were submitted to statistical analysis using level of significance set at P < 0.05. The PEG 1000 group obtained higher cell viability in comparison with HEMA in the 2 % primer. The cell survival rate using 20 % primer showed that PEG1000 and BIS-EMA 10 were less cytotoxic than HEMA. With regard to the eluate from bond resin, the data showed that the groups BIS-EMA 10, BIS-EMA 30 and PEG400UDMA were less cytotoxic than HEMA. No statistically significant difference was found among degrees of conversion of the experimental groups and HEMA. PEG 1000, BIS-EMA 10 and 30 monomers showed the biological potential for use in new adhesive system formulations since they showed lower cytotoxicity and similar degree of conversion when compared with the HEMA-containing group.

Contrasting evolutionary histories of MHC class I and class II loci in grouse—Effects of selection and gene conversion

USGS Publications Warehouse

Minias, Piotr; Bateson, Zachary W.; Whittingham, Linda A.; Johnson, Jeff A.; Oyler-McCance, Sara J.; Dunn, Peter O.

2016-01-01

Genes of the major histocompatibility complex (MHC) encode receptor molecules that are responsible for recognition of intracellular and extracellular pathogens (class I and class II genes, respectively) in vertebrates. Given the different roles of class I and II MHC genes, one might expect the strength of selection to differ between these two classes. Different selective pressures may also promote different rates of gene conversion at each class. Despite these predictions, surprisingly few studies have looked at differences between class I and II genes in terms of both selection and gene conversion. Here, we investigated the molecular evolution of MHC class I and II genes in five closely related species of prairie grouse (Centrocercus and Tympanuchus) that possess one class I and two class II loci. We found striking differences in the strength of balancing selection acting on MHC class I versus class II genes. More than half of the putative antigen-binding sites (ABS) of class II were under positive or episodic diversifying selection, compared with only 10% at class I. We also found that gene conversion had a stronger role in shaping the evolution of MHC class II than class I. Overall, the combination of strong positive (balancing) selection and frequent gene conversion has maintained higher diversity of MHC class II than class I in prairie grouse. This is one of the first studies clearly demonstrating that macroevolutionary mechanisms can act differently on genes involved in the immune response against intracellular and extracellular pathogens.

Contrasting evolutionary histories of MHC class I and class II loci in grouse—effects of selection and gene conversion

PubMed Central

Minias, P; Bateson, Z W; Whittingham, L A; Johnson, J A; Oyler-McCance, S; Dunn, P O

2016-01-01

Genes of the major histocompatibility complex (MHC) encode receptor molecules that are responsible for recognition of intracellular and extracellular pathogens (class I and class II genes, respectively) in vertebrates. Given the different roles of class I and II MHC genes, one might expect the strength of selection to differ between these two classes. Different selective pressures may also promote different rates of gene conversion at each class. Despite these predictions, surprisingly few studies have looked at differences between class I and II genes in terms of both selection and gene conversion. Here, we investigated the molecular evolution of MHC class I and II genes in five closely related species of prairie grouse (Centrocercus and Tympanuchus) that possess one class I and two class II loci. We found striking differences in the strength of balancing selection acting on MHC class I versus class II genes. More than half of the putative antigen-binding sites (ABS) of class II were under positive or episodic diversifying selection, compared with only 10% at class I. We also found that gene conversion had a stronger role in shaping the evolution of MHC class II than class I. Overall, the combination of strong positive (balancing) selection and frequent gene conversion has maintained higher diversity of MHC class II than class I in prairie grouse. This is one of the first studies clearly demonstrating that macroevolutionary mechanisms can act differently on genes involved in the immune response against intracellular and extracellular pathogens. PMID:26860199

Direct 1H NMR evidence of spin-rotation coupling as a source of para → ortho-H2 conversion in diamagnetic solvents.

PubMed

Terenzi, Camilla; Bouguet-Bonnet, Sabine; Canet, Daniel

2017-04-21

At ambient temperature, conversion from 100% enriched para-hydrogen (p-H 2 ; singlet state) to ortho-hydrogen (o-H 2 ; triplet state) leads necessarily to the thermodynamic equilibrium proportions: 75% of o-H 2 and 25% of p-H 2 . When p-H 2 is dissolved in a diamagnetic organic solvent, conversion is very slow and can be considered as arising from nuclear spin relaxation phenomena. A first relaxation mechanism, specific to the singlet state and involving a combination of auto-correlation and cross correlation spectral densities, can be retained: randomly fluctuating magnetic fields due to inter-molecular dipolar interactions. We demonstrate here that (i) this dipolar mechanism is not sufficient for accounting for the para→ortho conversion rate, (ii) spin-rotation interaction, an intra-molecular mechanism, behaves similarly to random-field interaction and, thus, may be involved in the singlet relaxation rate. Also, as the para→ortho conversion is monitored by proton nuclear magnetic resonance (NMR) of dissolved o-H 2 (p-H 2 is NMR-silent), one has to account for H 2 exchange between the liquid phase and the gas phase within the NMR tube, as well as for dissolution effects. Experimental evidence of the above statements is brought here in the case of two organic solvents: acetone-d 6 and carbon disulfide. The observed temperature dependence of the para→ortho conversion rate shows that spin-rotation can be the dominant contribution to the p-H 2 relaxation rate in the absence of tangible dipolar interactions. Our findings shed new light on the "mysterious" mechanism of the para→ortho conversion which has been searched for several decades.

New ortho-para conversion mechanism in dense solid hydrogen.

PubMed

Strzhemechny, M A; Hemley, R J

2000-12-25

Analysis of recent measurements of striking changes in the rate of ortho-para conversion of solid H(2) up to 58 GPa shows that the conversion mechanism must differ from that at ambient pressure. A new conversion mechanism is identified in which the emerging excitations are coupled to the converting molecules via electric quadrupole-quadrupole rather than nuclear spin-spin interactions. The latter only initiates conversion while the coupling enhancement associated with the new mechanism is ensured by high compression and a gap closing, with the conversion energy diminishing strongly with increasing pressure.

Effect of mineral nutrients on cell growth and self-flocculation of Tolypothrix tenuis for the production of a biofertilizer.

PubMed

Silva, P G; Silva, H J

2007-02-01

The influence of mineral nutrients on the growth and self-flocculation of Tolypothrix tenuis was studied. The identification of possible limiting nutrients in the culture medium was performed by the biomass elemental composition approach. A factorial experimental design was used in order to estimate the contribution of macronutrients and micronutrients, as well as their interactions. Iron was identified to be limiting in the culture medium. The micronutrients influenced mainly cellular growth without effects on self-flocculation. Conversely, the self-flocculation capacity of the biomass increased at higher concentrations of macronutrients. The optimization of mineral nutrition of T. tenuis allowed a 73% increase in the final biomass level and 3.5 times higher flocculation rates.

Energy conversion in isothermal nonlinear irreversible processes - struggling for higher efficiency

NASA Astrophysics Data System (ADS)

Ebeling, W.; Feistel, R.

2017-06-01

First we discuss some early work of Ulrike Feudel on structure formation in nonlinear reactions including ions and the efficiency of the conversion of chemical into electrical energy. Then we give some survey about isothermal energy conversion from chemical to higher forms of energy like mechanical, electrical and ecological energy. Isothermal means here that there are no temperature gradients within the model systems. We consider examples of energy conversion in several natural processes and in some devices like fuel cells. Further, as an example, we study analytically the dynamics and efficiency of a simple "active circuit" converting chemical into electrical energy and driving currents which is roughly modeling fuel cells. Finally we investigate an analogous ecological system of Lotka-Volterra type consisting of an "active species" consuming some passive "chemical food". We show analytically for both these models that the efficiency increases with the load, reaches values higher then 50 percent in a narrow regime of optimal load and goes beyond some maximal load abruptly to zero.

Kinetic phase evolution of spinel cobalt oxide during lithiation

DOE PAGES

Li, Jing; He, Kai; Meng, Qingping; ...

2016-09-15

Spinel cobalt oxide has been proposed to undergo a multiple-step reaction during the electrochemical lithiation process. Understanding the kinetics of the lithiation process in this compound is crucial to optimize its performance and cyclability. In this work, we have utilized a low-angle annular dark-field scanning transmission electron microscopy method to visualize the dynamic reaction process in real time and study the reaction kinetics at different rates. We show that the particles undergo a two-step reaction at the single-particle level, which includes an initial intercalation reaction followed by a conversion reaction. At low rates, the conversion reaction starts after the intercalationmore » reaction has fully finished, consistent with the prediction of density functional theoretical calculations. At high rates, the intercalation reaction is overwhelmed by the subsequently nucleated conversion reaction, and the reaction speeds of both the intercalation and conversion reactions are increased. Phase-field simulations show the crucial role of surface diffusion rates of lithium ions in controlling this process. Furthermore, this work provides microscopic insights into the reaction dynamics in non-equilibrium conditions and highlights the effect of lithium diffusion rates on the overall reaction homogeneity as well as the performance.« less

Kinetic phase evolution of spinel cobalt oxide during lithiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Jing; He, Kai; Meng, Qingping

Spinel cobalt oxide has been proposed to undergo a multiple-step reaction during the electrochemical lithiation process. Understanding the kinetics of the lithiation process in this compound is crucial to optimize its performance and cyclability. In this work, we have utilized a low-angle annular dark-field scanning transmission electron microscopy method to visualize the dynamic reaction process in real time and study the reaction kinetics at different rates. We show that the particles undergo a two-step reaction at the single-particle level, which includes an initial intercalation reaction followed by a conversion reaction. At low rates, the conversion reaction starts after the intercalationmore » reaction has fully finished, consistent with the prediction of density functional theoretical calculations. At high rates, the intercalation reaction is overwhelmed by the subsequently nucleated conversion reaction, and the reaction speeds of both the intercalation and conversion reactions are increased. Phase-field simulations show the crucial role of surface diffusion rates of lithium ions in controlling this process. Furthermore, this work provides microscopic insights into the reaction dynamics in non-equilibrium conditions and highlights the effect of lithium diffusion rates on the overall reaction homogeneity as well as the performance.« less

Selling the story: Narratives and charisma in adults with TBI

PubMed Central

JONES, CORINNE A.; TURKSTRA, LYN S.

2015-01-01

Objective To examine storytelling performance behaviours in adults with traumatic brain injury (TBI) and relate these behaviours to perceived charisma and desirability as a conversation partner. Design and methods Seven adult males with traumatic brain injury (TBI) told their accident narratives to a male confederate. Ten male undergraduate students rated 1-minute video clips from the beginning of each narrative using the Charismatic Leadership Communication Scale (CLCS). Raters also indicated whether or not they would like to engage in conversation with each participant. Results Of the performative behaviours analysed, gestures alone significantly influenced CLCS ratings and reported likelihood of engaging in future conversation with the participant. Post-hoc analysis revealed that speech rate was significantly correlated with all of the preceding measures. There was a significant correlation between self- and other-ratings of charisma. Conclusions The findings suggest that aspects of non-verbal performance, namely gesture use and speech rate, influence how charismatic an individual is perceived to be and how likely someone is to engage in conversation with that person. Variability in these performance behaviours may contribute to the variation in social outcomes seen in the TBI population. PMID:21714624

Investigation of Redox Metal Oxides for Carbonaceous Fuel Conversion and CO2 Capture

NASA Astrophysics Data System (ADS)

Galinsky, Nathan Lee

The chemical looping combustion (CLC) process uses metal oxides, also referred to as oxygen carriers, in a redox scheme for conversion of carbonaceous fuels into a concentrated stream of CO2 and steam while also producing heat and electricity. The unique redox scheme of CLC allows CO2 capture with minimal energy penalty. The CLC process performance greatly depends on the oxygen carrier that is chosen. To date, more than 1000 oxygen carriers have been developed for chemical-looping processes using metal oxides containing first-row transition metals. Oxygen carriers are typically mixed with an inert ceramic support to improve their overall mechanical stability and recyclability. This study focuses on design of (i) iron oxide oxygen carriers for conversion of gaseous carbonaceous fuels and (ii) development of perovskite CaMnO 3-d with improved stability and redox properties for conversion of solid fuels. Iron oxide is cheap and environmentally benign. However, it suffers from low activity with carbonaceous fuels due partially to the low ionic conductivity of iron oxides. In order to address the low activity of iron-oxide-based oxygen carriers, support addition has been shown to lower the energy barrier of oxygen anion transport within the oxygen carrier. This work adds a mixed-ionic-and-electronic-conductor (MIEC) support to iron oxide to help facilitate O2- transport inside the lattice of iron oxide. The MIEC-supported iron oxide is compared to commonly used supports including TiO2 and Al2O 3 and the pure ionic conductor support yttria-stabilized zirconia (YSZ) for conversion of different carbonaceous fuels and hydrogen. Results show that the MIEC-supported iron oxide exhibits up to 70 times higher activity than non-MIEC-supported iron oxides for methane conversion. The MIEC supported iron oxide also shows good recyclability with only minor agglomeration and carbon formation observed. The effect of support-iron oxide synergies is further investigated to understand other physical and chemical properties that lead to highly active and recyclable oxygen carriers. Perovskite and fluorite-structured MIEC supports are tested for conversion of methane. The perovskite supported iron oxides exhibit higher activity and stability resulting from the high mixed conductivity of the support. Fluorite-structured CeO2 oxygen carriers deactivated by 75% after 10 redox cycles. This deactivation was attributed to agglomeration of iron oxide. The agglomeration was determined to occur due to Fe x+ transport during the oxidation step leading to high content of Fe on the surface of the oxygen carrier. Besides the MIEC supports, inert MgAl2O4 supported iron oxide is observed to activate in methane. The activation is attributed to carbon formation causing physical degradation of the oxygen carrier and leading to higher surface area and porosity. To achieve high activity with solid fuels, chemical looping with oxygen uncoupling (CLOU) is commonly used. This process uses oxygen carriers with high PO2 that allows the oxygen carrier to release a portion of their lattice oxygen as gaseous oxygen. In turn, the gaseous oxygen can react with solid fuel particles at a higher rate than the lattice oxygen. CaMnO 3 perovskite oxygen carriers offer high potential for CLOU. However, pure CaMnO3 suffers from long-term recyclability and sulfur poisoning. Addition of A-site (Ba and Sr) and B-site (Fe, Ni, Co, Al, and V) dopants are used to improve the performance of the base CaMnO3 oxygen carrier. Sr (A-site) and Fe (B-site) exhibit high compatibility with the base perovskite structure. Both dopants observe oxygen uncoupling properties up to 200°C below that of pure CaMnO3. Additionally, the doped structures also exhibit higher stability at high temperatures (>1000°C) and during redox cycles. The doped oxygen carriers also demonstrate significantly improved activity for coal char conversion.

Study of parameters affecting the conversion in a plug flow reactor for reactions of the type 2A→B

NASA Astrophysics Data System (ADS)

Beltran-Prieto, Juan Carlos; Long, Nguyen Huynh Bach Son

2018-04-01

Modeling of chemical reactors is an important tool to quantify reagent conversion, product yield and selectivity towards a specific compound and to describe the behavior of the system. Proposal of differential equations describing the mass and energy balance are among the most important steps required during the modeling process as they play a special role in the design and operation of the reactor. Parameters governing transfer of heat and mass have a strong relevance in the rate of the reaction. Understanding this information is important for the selection of reactor and operating regime. In this paper we studied the irreversible gas-phase reaction 2A→B. We model the conversion that can be achieved as function of the reactor volume and feeding temperature. Additionally, we discuss the effect of activation energy and the heat of reaction on the conversion achieved in the tubular reactor. Furthermore, we considered that dimerization occurs instantaneously in the catalytic surface to develop equations for the determination of rate of reaction per unit area of three different catalytic surface shapes. This data can be combined with information about the global rate of conversion in the reactor to improve regent conversion and yield of product.

Auger Up-Conversion of Low-Intensity Infrared Light in Engineered Quantum Dots

DOE PAGES

Makarov, Nikolay S.; Lin, Qianglu; Pietryga, Jeffrey M.; ...

2016-11-29

One source of efficiency losses in photovoltaic cells is their transparency toward solar photons with energies below the band gap of the absorbing layer. This loss can be reduced using a process of up-conversion whereby two or more sub-band-gap photons generate a single above-gap exciton. Traditional approaches to up-conversion, such as nonlinear two-photon absorption (2PA) or triplet fusion, suffer from low efficiency at solar light intensities, a narrow absorption bandwidth, nonoptimal absorption energies, and difficulties for implementing in practical devices. We show that these deficiencies can be alleviated using the effect of Auger up-conversion in thick-shell PbSe/CdSe quantum dots. Thismore » process relies on Auger recombination whereby two low-energy, core-based excitons are converted into a single higher-energy, shell-based exciton. When compared to their monocomponent counterparts, the tailored PbSe/CdSe heterostructures feature enhanced absorption cross-sections, a higher efficiency of the “productive” Auger pathway involving re-excitation of a hole, and longer lifetimes of both core- and shell-localized excitons. These features lead to effective up-conversion cross-sections that are more than 6 orders of magnitude higher than for standard nonlinear 2PA, which allows for efficient up-conversion of continuous wave infrared light at intensities as low as a few watts per square centimeter.« less

Hydroprocessing of rubber seed oil to renewable fuels

NASA Astrophysics Data System (ADS)

Tran, Tan Viet; Phung, Minh Tri

2017-09-01

Hydroprocessing of rubber seed oil (RSO) with various types of alumina-silica support catalyst was conducted at 400°C and a hydrogen partial pressure of 3.0 MPa in 3 hours. The effects of the alumina-silica and metal doping on alumina-silica on the conversion, and distribution of oil fraction products (initial boiling point (IBP) to 80°C, from 80-200°C, from 200-360°C and higher than 360°C boiling point) were investigated. Compared to the results obtained when using Mo@Al2O3-SiO2, hydroprocessing of RSO resulted in a higher conversion and much higher yield of the light fraction (BP <230°C). Both alumina-silica catalysts led to an improved conversion as well as a higher light fraction yield. Results show that hydroprocessing of RSO with metal doping on alumina-silica support was more efficient than that only Al2O3-SiO2.

Estimating Bacterial Production in Marine Waters from the Simultaneous Incorporation of Thymidine and Leucine

PubMed Central

Chin-Leo, Gerardo; Kirchman, David L.

1988-01-01

We examined the simultaneous incorporation of [3H]thymidine and [14C]leucine to obtain two independent indices of bacterial production (DNA and protein syntheses) in a single incubation. Incorporation rates of leucine estimated by the dual-label method were generally higher than those obtained by the single-label method, but the differences were small (dual/single = 1.1 ± 0.2 [mean ± standard deviation]) and were probably due to the presence of labeled leucyl-tRNA in the cold trichloroacetic acid-insoluble fraction. There were no significant differences in thymidine incorporation between dual- and single-label incubations (dual/ single = 1.03 ± 0.13). Addition of the two substrates in relatively large amounts (25 nM) did not apparently increase bacterial activity during short incubations (<5 h). With the dual-label method we found that thymidine and leucine incorporation rates covaried over depth profiles of the Chesapeake Bay. Estimates of bacterial production based on thymidine and leucine differed by less than 25%. Although the need for appropriate conversion factors has not been eliminated, the dual-label approach can be used to examine the variation in bacterial production while ensuring that the observed variation in incorporation rates is due to real changes in bacterial production rather than changes in conversion factors or introduction of other artifacts. PMID:16347706

5 CFR 536.302 - Optional pay retention.

Code of Federal Regulations, 2010 CFR

2010-01-01

... conversion rule in § 536.303(a) before determining whether an employee's rate of basic pay otherwise would be... entitled to pay retention under § 536.301, but whose payable rate of basic pay otherwise would be reduced (after application of any applicable geographic conversion under § 536.303(a)) as the result of a...

5 CFR 9901.314 - National security compensation comparability.

Code of Federal Regulations, 2010 CFR

2010-01-01

... conversion of such employees to the NSPS; and (2) Adjustments for normal step increases and rates of... disadvantaged in terms of the overall amount of compensation available as a result of conversion to the NSPS.... 5304, special rate supplement under 5 U.S.C. 5305, local market supplement under § 9901.332, or...

Condensed phase conversion and growth of nanorods and other materials instead of from vapor

DOEpatents

Geohegan, David B.; Seals, Roland D.; Puretzky, Alex A.; Fan, Xudong

2010-10-19

Compositions, systems and methods are described for condensed phase conversion and growth of nanorods and other materials. A method includes providing a condensed phase matrix material; and activating the condensed phase matrix material to produce a plurality of nanorods by condensed phase conversion and growth from the condensed phase matrix material instead of from vapor. The compositions are very strong. The compositions and methods provide advantages because they allow (1) formation rates of nanostructures necessary for reasonable production rates, and (2) the near net shaped production of component structures.

Condensed phase conversion and growth of nanorods instead of from vapor

DOEpatents

Geohegan, David B.; Seals, Roland D.; Puretzky, Alex A.; Fan, Xudong

2005-08-02

Compositions, systems and methods are described for condensed phase conversion and growth of nanorods and other materials. A method includes providing a condensed phase matrix material; and activating the condensed phase matrix material to produce a plurality of nanorods by condensed phase conversion and growth from the condensed chase matrix material instead of from vacor. The compositions are very strong. The compositions and methods provide advantages because they allow (1) formation rates of nanostructures necessary for reasonable production rates, and (2) the near net shaped production of component structures.

Effect of pretreatment severity in continuous steam explosion on enzymatic conversion of wheat straw: Evidence from kinetic analysis of hydrolysis time courses.

PubMed

Monschein, Mareike; Nidetzky, Bernd

2016-01-01

Focusing on continuous steam explosion, the influence of pretreatment severity due to varied acid loading on hydrolysis of wheat straw by Trichoderma reesei cellulases was investigated based on kinetic evaluation of the saccharification of each pretreated substrate. Using semi-empirical descriptors of the hydrolysis time course, key characteristics of saccharification efficiency were captured in a quantifiable fashion. Not only hydrolysis rates per se, but also the transition point of their bi-phasic decline was crucial for high saccharification degree. After 48h the highest saccharification was achieved for substrate pretreated at relatively low severity (1.2% acid). Higher severity increased enzyme binding to wheat straw, but reduced the specific hydrolysis rates. Higher affinity of the lignocellulosic material for cellulases does not necessarily result in increased saccharification, probably because of lignin modifications occurring at high pretreatment severities. At comparable severity, continuous pretreatment produced a substrate more susceptible to enzymatic hydrolysis than the batch process. Copyright © 2015 Elsevier Ltd. All rights reserved.

The correlates of obsessive-compulsive, schizotypal, and borderline personality disorders in obsessive-compulsive disorder.

PubMed

Melca, Isabela A; Yücel, Murat; Mendlowicz, Mauro V; de Oliveira-Souza, Ricardo; Fontenelle, Leonardo F

2015-06-01

We assessed correlates of obsessive-compulsive (OCPD), schizotypal (SPD) and borderline (BPD) personality disorders in 110 obsessive-compulsive disorder (OCD) patients. We found OCD patients with OCPD (20.9%) to exhibit higher rates of hoarding and bipolar disorders, increased severity of hoarding and symmetry, lower prevalence of unacceptable thoughts involving sex and religion and less non-planning impulsivity. Conversely, OCD patients with SPD (13.6%) displayed more frequently bipolar disorder, increased severity of depression and OCD neutralization, greater prevalence of "low-order" behaviors (i.e., touching), lower low-planning impulsivity and greater "behavioral" compulsivity. Finally, in exploratory analyses, OCD patients with BPD (21.8%) exhibited lower education, higher rates of several comorbid psychiatric disorders, greater frequency of compulsions involving interpersonal domains (e.g. reassurance seeking), increased severity of depression, anxiety and OCD dimensions other than symmetry and hoarding, more motor and non-planning impulsivity, and greater "cognitive" compulsivity. These findings highlight the importance of assessing personality disorders in OCD samples. Copyright © 2015 Elsevier Ltd. All rights reserved.

The effects of impression management demands on heart rate, self-reported social anxiety, and social competence in undergraduate males.

PubMed

Sheffer, C E; Penn, D L; Cassisi, J E

2001-01-01

The effects of self-presentation demands were evaluated through conversational probe (CP) role-play tasks. Participants (N = 29) were required to manage their self-presentations (i.e., the impression they made, in each of two conditions). During high impression management (IM) demand, participants were evaluated on their performance. During Low IM demand, participants evaluated a confederate's performance. The High IM demand condition produced significantly higher heart rate (HR) and self-reported anxiety. HR and self-reported anxiety accounted for a significant amount of the variance in criterion measures of social competence. Greater social competence during High IM was associated with higher HR. Greater social competence during Low IM was associated with lower HR and lower self-reported anxiety. Although preliminary, these results suggest that uncontrolled IM demands contributed to mixed results found within and between social anxiety studies in the literature. Implications for the treatment of social anxiety are discussed.

Investigating pyrolysis characteristics of moso bamboo through TG-FTIR and Py-GC/MS.

PubMed

Liang, Fang; Wang, Ruijuan; Hongzhong, Xiang; Yang, Xiaomeng; Zhang, Tao; Hu, Wanhe; Mi, Bingbing; Liu, Zhijia

2018-05-01

This study was carried out to investigate pyrolysis characteristics of moso bamboo (Phyllostachys pubescens), including outer layer (OB), middle layer (MB) and inner layer (IB) and bamboo leaves (BL), through TG-FTIR and Py-GC/MS. The results showed that 70% of weight loss occurred at rapid pyrolysis stage with temperature of 200-400 °C. With increase in heating rate, pyrolysis process shifted toward higher temperature. IB, OB, MB and BL had a different activation energy at different conversion rates. BL had a higher activation energy than IB, OB and MB. The volatiles of bamboo was complicated with 2-30 of C atoms. IB, OB and MB mainly released benzofuran, hydroxyacetaldehyde and 2-Pentanone. BL released furan, acetic acid and phenol. The main pyrolysis products included H 2 O, CH 4 , CO 2 , CO, carboxylic acids, NO, NO 2 . Pyrolysis products of IB was the most and that of BL was the lowest. MB had the lowest pyrolysis temperature. Copyright © 2018 Elsevier Ltd. All rights reserved.

26 CFR 1.305-6 - Distributions of convertible preferred.

Code of Federal Regulations, 2010 CFR

2010-04-01

... the following conditions exist: (i) The conversion right must be exercised within a relatively short... the dividend rate, the redemption provisions, the marketability of the convertible stock, and the conversion price, it may be anticipated that some shareholders will exercise their conversion rights and some...

[Influence of elevated atmospheric CO2 concentration on photosynthesis and leaf nitrogen partition in process of photosynthetic carbon cycle in Musa paradisiaca].

PubMed

Sun, G; Zhao, P; Zeng, X; Peng, S

2001-06-01

The photosynthetic rate (Pn) in leaves of Musa paradisiaca grown under elevated CO2 concentration (700 +/- 56 microliters.L-1) for one week was 5.14 +/- 0.32 mumol.m-2.s-1, 22.1% higher than that under ambient CO2 concentration, while under elevated CO2 concentration for 8 week, the Pn decreased by 18.1%. It can be inferred that the photosynthetic acclimation to elevated CO2 concentration and the Pn inhibition occurred in leaves of M. paradisiaca. The respiration rate in light (Rd) was lower in leaves under higher CO2 concentration, compared with that under ambient CO2 concentration. If the respiration in light was not included, the difference in CO2 compensation point for the leaves of both plants was not significant. Under higher CO2 concentration for 8 weeks, the maximum carboxylation rate(Vcmax) and electron transportation rate (J) in leaves decreased respectively by 30.5% and 14.8%, compared with that under ambient CO2 concentration. The calculated apparent quantum yield (alpha) in leaves under elevated CO2 concentration according to the initial slope of Pn/PAR was reduced to 0.014 +/- 0.010 molCO2.mol-1 quanta, compared with the value of 0.025 +/- 0.005 molCO2.mol-1 quanta in the control. The efficiency of light energy conversion also decreased from 0.203 to 0.136 electrons.quanta-1 in plants under elevated CO2 concentration. A lower partitioning coefficient for leaf nitrogen in Rubisco, bioenergetics and thylakoid light-harvesting components was observed in plants under higher CO2 concentration. The results indicated that the multi-process of photosynthesis was suppressed significantly by a long-term (8 weeks) higher CO2 concentration incubation.

Continuous Hydrolysis of Pectate by Immobilized Endo-polygalacturonase in a Continuously Stirred Tank Reactor.

PubMed

Iwasaki, K; Inoue, M; Matsubara, Y

1998-01-01

Enzymatic hydrolysis of pectate was carried out continuously to produce pectate oligosaccharides by immobilized endo-polygalacturonase in a continuous stirred tank reactor (CSTR) with high efficiency. The enzyme was immobilized on to chitosan beads by the absorption method, and the reaction was performed with an initial pectate concentration of 10 gl(-1) at 35°C and pH 4.0 at a dilution rate of 0.87-2.8 h(-1). The hydrolysis products mainly consisted of mono-, di-, tri-, tetra-, penta-, hexa- and heptasaccharides, with the highest conversion being 0.78. A higher volumetric production rate of the total hydrolyzate, which was dependent on the dilution rate, was obtained than that by a batch reaction. The hydrolysis process was mathematically modeled from the basic material balance and rate equations, and showed agreement between the simulated and experimental results. This reactor system was found to be effective for obtaining pectate oligosaccharides with a high production rate.

Dose-to-water conversion for the backscatter-shielded EPID: A frame-based method to correct for EPID energy response to MLC transmitted radiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zwan, Benjamin J., E-mail: benjamin.zwan@uon.edu.au; O’Connor, Daryl J.; King, Brian W.

2014-08-15

Purpose: To develop a frame-by-frame correction for the energy response of amorphous silicon electronic portal imaging devices (a-Si EPIDs) to radiation that has transmitted through the multileaf collimator (MLC) and to integrate this correction into the backscatter shielded EPID (BSS-EPID) dose-to-water conversion model. Methods: Individual EPID frames were acquired using a Varian frame grabber and iTools acquisition software then processed using in-house software developed inMATLAB. For each EPID image frame, the region below the MLC leaves was identified and all pixels in this region were multiplied by a factor of 1.3 to correct for the under-response of the imager tomore » MLC transmitted radiation. The corrected frames were then summed to form a corrected integrated EPID image. This correction was implemented as an initial step in the BSS-EPID dose-to-water conversion model which was then used to compute dose planes in a water phantom for 35 IMRT fields. The calculated dose planes, with and without the proposed MLC transmission correction, were compared to measurements in solid water using a two-dimensional diode array. Results: It was observed that the integration of the MLC transmission correction into the BSS-EPID dose model improved agreement between modeled and measured dose planes. In particular, the MLC correction produced higher pass rates for almost all Head and Neck fields tested, yielding an average pass rate of 99.8% for 2%/2 mm criteria. A two-sample independentt-test and fisher F-test were used to show that the MLC transmission correction resulted in a statistically significant reduction in the mean and the standard deviation of the gamma values, respectively, to give a more accurate and consistent dose-to-water conversion. Conclusions: The frame-by-frame MLC transmission response correction was shown to improve the accuracy and reduce the variability of the BSS-EPID dose-to-water conversion model. The correction may be applied as a preprocessing step in any pretreatment portal dosimetry calculation and has been shown to be beneficial for highly modulated IMRT fields.« less

Hip arthroscopy utilization and associated complications: a population-based analysis

PubMed Central

Bernard, Johnathan A.; Pan, Ting J.; Ranawat, Anil S.; Nawabi, Danyal H.; Kelly, Bryan T.; Lyman, Stephen

2017-01-01

Abstract The purpose of this study is to review the trends in hip arthroscopy using data from a statewide database, focusing on utilization rates, patient demographics and complication rates. The Statewide Planning and Research Cooperative System (SPARCS) database for New York State was queried for cases of hip arthroscopy from 1998 to 2012. Patient demographics and procedural details were collected. Patients were subsequently reviewed for complications and readmissions within 30 and 90 days. In total, 12 194 hip arthroscopy procedures were performed by 295 surgeons in 137 centers between 1998 and 2012. There was a 95-fold increase in the annual frequency of hip arthroscopy procedures between 1998 (n = 24) and 2012 (n = 2296). Thirty-day complication rates were 0.2% (n = 19), whereas the 90-day complication rate was 0.3% (n = 30). The all-cause 30-day readmission rate was 0.5% (n = 66), whereas the 90-day rate was 1.6% (n = 200). The number of surgeons performing hip arthroscopy increased 7-fold over the observation period. However, only 14.9% (n = 44) of surgeons performed more than 30 procedures annually. Lower volume surgeons (<102 cases/year) demonstrated significantly higher 90-day readmission rates, compared with higher volume surgeons (>163 cases/year, P < 0.0060); however, complication rates and readmission rates did not differ based on surgeon volume. Our findings confirm our hypothesis, demonstrating a significant increase in utilization of hip arthroscopy in the State of New York. We did not identify an associated increase in annual complication rates as hypothesized with increasing utilization, although there was an association of higher readmission rates among lower volume surgeons. Further study is needed to define rates of failure requiring revision hip arthroscopy or conversion to arthroplasty, and to clarify the relationship between complication rates and surgeon volume and case complexity. Level of Evidence: III, retrospective cohort series. PMID:28948036

Direct digital conversion detector technology

NASA Astrophysics Data System (ADS)

Mandl, William J.; Fedors, Richard

1995-06-01

Future imaging sensors for the aerospace and commercial video markets will depend on low cost, high speed analog-to-digital (A/D) conversion to efficiently process optical detector signals. Current A/D methods place a heavy burden on system resources, increase noise, and limit the throughput. This paper describes a unique method for incorporating A/D conversion right on the focal plane array. This concept is based on Sigma-Delta sampling, and makes optimum use of the active detector real estate. Combined with modern digital signal processors, such devices will significantly increase data rates off the focal plane. Early conversion to digital format will also decrease the signal susceptibility to noise, lowering the communications bit error rate. Computer modeling of this concept is described, along with results from several simulation runs. A potential application for direct digital conversion is also reviewed. Future uses for this technology could range from scientific instruments to remote sensors, telecommunications gear, medical diagnostic tools, and consumer products.

Geographic Differences in Time to Culture Conversion in Liquid Media: Tuberculosis Trials Consortium Study 28. Culture Conversion Is Delayed in Africa

PubMed Central

Mac Kenzie, William R.; Heilig, Charles M.; Bozeman, Lorna; Johnson, John L.; Muzanye, Grace; Dunbar, Denise; Jost, Kenneth C.; Diem, Lois; Metchock, Beverly; Eisenach, Kathleen; Dorman, Susan; Goldberg, Stefan

2011-01-01

Background Tuberculosis Trials Consortium Study 28, was a double blind, randomized, placebo-controlled, phase 2 clinical trial examining smear positive pulmonary Mycobacterium tuberculosis. Over the course of intensive phase therapy, patients from African sites had substantially delayed and lower rates of culture conversion to negative in liquid media compared to non-African patients. We explored potential explanations of this finding. Methods In TBTC Study 28, protocol-correct patients (n = 328) provided spot sputum specimens for M. tuberculosis culture in liquid media, at baseline and weeks 2, 4, 6 and 8 of study therapy. We compared sputum culture conversion for African and non-African patients stratified by four baseline measures of disease severity: AFB smear quantification, extent of disease on chest radiograph, cavity size and the number of days to detection of M. tuberculosis in liquid media using the Kaplan-Meier product-limit method. We evaluated specimen processing and culture procedures used at 29 study laboratories serving 27 sites. Results African TB patients had more extensive disease at enrollment than non-African patients. However, African patients with the least disease by the 4 measures of disease severity had conversion rates on liquid media that were substantially lower than conversion rates in non-African patients with the greatest extent of disease. HIV infection, smoking and diabetes did not explain delayed conversion in Africa. Some inter-site variation in laboratory processing and culture procedures within accepted practice for clinical diagnostic laboratories was found. Conclusions Compared with patients from non-African sites, African patients being treated for TB had delayed sputum culture conversion and lower sputum conversion rates in liquid media that were not explained by baseline severity of disease, HIV status, age, smoking, diabetes or race. Further investigation is warranted into whether modest variation in laboratory processes substantially influences the efficacy outcomes of phase 2 TB treatment trials or if other factors (e.g., nutrition, host response) are involved. Trial Registration ClinicalTrials.gov NCT00144417 PMID:21494548

Impact of the oxygen defects and the hydrogen concentration on the surface of tetragonal and monoclinic ZrO2 on the reduction rates of stearic acid on Ni/ZrO2.

PubMed

Foraita, Sebastian; Fulton, John L; Chase, Zizwe A; Vjunov, Aleksei; Xu, Pinghong; Baráth, Eszter; Camaioni, Donald M; Zhao, Chen; Lercher, Johannes A

2015-02-02

The role of the specific physicochemical properties of ZrO2 phases on Ni/ZrO2 has been explored with respect to the reduction of stearic acid. Conversion on pure m-ZrO2 is 1.3 times more active than on t-ZrO2 , whereas Ni/m-ZrO2 is three times more active than Ni/t-ZrO2 . Although the hydrodeoxygenation of stearic acid can be catalyzed solely by Ni, the synergistic interaction between Ni and the ZrO2 support causes the variations in the reaction rates. Adsorption of the carboxylic acid group on an oxygen vacancy of ZrO2 and the abstraction of the α-hydrogen atom with the elimination of the oxygen atom to produce a ketene is the key to enhance the overall rate. The hydrogenated intermediate 1-octadecanol is in turn decarbonylated to heptadecane with identical rates on all catalysts. Decarbonylation of 1-octadecanol is concluded to be limited by the competitive adsorption of reactants and intermediate. The substantially higher adsorption of propionic acid demonstrated by IR spectroscopy and the higher reactivity to O2 exchange reactions with the more active catalyst indicate that the higher concentration of active oxygen defects on m-ZrO2 compared to t-ZrO2 causes the higher activity of Ni/m-ZrO2 . © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

FY17-PDH-EVTest04 GodInput Impact of the Oxygen Defects1 FY17-PDH-EVTest04 Reduction Rates of Stearic AcidFY17-PDH-T04.

PubMed

Foraita, Sebastian; Fulton, John L; Chase, Zizwe A; Vjunov, Aleksei; Xu, Pinghong; Baráth, Eszter; Camaioni, Donald M; Zhao, Chen; Lercher, Johannes A

2016-08-10

Test New Article1 GodEarlyview.Publish-on-load testing.The role of the specific physicochemical properties of ZrO 2 phases on Ni/ZrO 2 has been explored with respect to the reduction of stearic acid. Conversion on pure m?ZrO 2 is 1.3 times more active than on t?ZrO 2 , whereas Ni/m?ZrO 2 is three times more active than Ni/t?ZrO 2 . Although the hydrodeoxygenation of stearic acid can be catalyzed solely by Ni, the synergistic interaction between Ni and the ZrO 2 support causes the variations in the reaction rates. Adsorption of the carboxylic acid group on an oxygen vacancy of ZrO 2 and the abstraction of the ??hydrogen atom with the elimination of the oxygen atom to produce a ketene is the key to enhance the overall rate. The hydrogenated intermediate 1?octadecanol is in turn decarbonylated to heptadecane with identical rates on all catalysts. Decarbonylation of 1?octadecanol is concluded to be limited by the competitive adsorption of reactants and intermediate. The substantially higher adsorption of propionic acid demonstrated by IR spectroscopy and the higher reactivity to O 2 exchange reactions with the more active catalyst indicate that the higher concentration of active oxygen defects on m?ZrO 2 compared to t?ZrO 2 causes the higher activity of Ni/m?ZrO 2 . © 2015 WILEY?VCH Verlag GmbH & Co. KGaA, Weinheim.

VizieR Online Data Catalog: Flux conversion factors for the Swift/UVOT filters (Brown+, 2016)

NASA Astrophysics Data System (ADS)

Brown, P. J.; Breeveld, A.; Roming, P. W. A.; Siegel, M.

2016-10-01

The conversion of observed magnitudes (or the actual observed photon or electron count rates) to a flux density is one of the most fundamental calculations. The flux conversions factors for the six Swift/UVOT filters are tabulated in Table1. (1 data file).

Risk factors for conversion from unipolar psychotic depression to bipolar disorder.

PubMed

Østergaard, Søren Dinesen; Straszek, Sune; Petrides, Georgios; Skadhede, Søren; Jensen, Signe Olrik Wallenstein; Munk-Jørgensen, Povl; Nielsen, Jimmi

2014-03-01

Patients with unipolar psychotic depression (PD) are at high risk of developing bipolar disorder (BD). This conversion has important implications for the choice of treatment. This study, therefore, aimed to identify risk factors associated with diagnostic conversion from PD to BD. We conducted a population-based, historical prospective cohort study by merging data from Danish registers. Patients assigned an ICD-10 diagnosis of PD between 1 January 1995 and 31 December 2007 were identified in the Danish Central Psychiatric Research Register and were followed until the development of BD, death, loss to follow-up, or 31 December 2007. Potential risk factors for conversion to BD, also defined through various Danish registers, were tested in multiple logistic regression analyses with risk expressed as adjusted odds ratios (AOR). We identified 8,588 patients with PD, of whom 609 (7.1%) developed BD during follow-up. The following characteristics were significantly associated with diagnostic conversion from PD to BD: early onset of PD [AOR = 0.99 (per year of increasing age), p = 0.044], recurrent depression [AOR = 1.02 (per episode), p = 0.036], living alone (AOR = 1.29, p = 0.007), receiving a disability pension (AOR = 1.55, p < 0.001), and the highest educational level being a technical education (AOR = 1.55, p < 0.001), short-cycle higher education (AOR = 2.65, p < 0.001), or medium-cycle higher education (AOR = 1.75, p < 0.001). Diagnostic conversion to BD was prevalent among patients with PD. The following characteristics were significantly associated with this conversion: early onset of PD, recurrent depression, living alone, receiving a disability pension, and the highest educational level being a technical education, short-cycle higher education, or medium-cycle higher education. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Conversion of a micro, glow-ignition, two-stroke engine from nitromethane-methanol blend fuel to military jet propellant (JP-8)

NASA Astrophysics Data System (ADS)

Wiegand, Andrew L.

The goal of the thesis "Conversion of a Micro, Glow-Ignition, Two-Stroke Engine from Nitromethane-Methanol Blend Fuel to Military Jet Propellant (JP-8)" was to demonstrate the ability to operate a small engine on JP-8 and was completed in two phases. The first phase included choosing, developing a test stand for, and baseline testing a nitromethane-methanol-fueled engine. The chosen engine was an 11.5 cc, glow-ignition, two-stroke engine designed for remote-controlled helicopters. A micro engine test stand was developed to load and motor the engine. Instrumentation specific to the low flow rates and high speeds of the micro engine was developed and used to document engine behavior. The second phase included converting the engine to operate on JP-8, completing JP-8-fueled steady-state testing, and comparing the performance of the JP-8-fueled engine to the nitromethane-methanol-fueled engine. The conversion was accomplished through a novel crankcase heating method; by heating the crankcase for an extended period of time, a flammable fuel-air mixture was generated in the crankcase scavenged engine, which greatly improved starting times. To aid in starting and steady-state operation, yttrium-zirconia impregnated resin (i.e. ceramic coating) was applied to the combustion surfaces. This also improved the starting times of the JP-8-fueled engine and ultimately allowed for a 34-second starting time. Finally, the steady-state data from both the nitromethane-methanol and JP-8-fueled micro engine were compared. The JP-8-fueled engine showed signs of increased engine friction while having higher indicated fuel conversion efficiency and a higher overall system efficiency. The minimal ability of JP-8 to cool the engine via evaporative effects, however, created the necessity of increased cooling air flow. The conclusion reached was that JP-8-fueled micro engines could be viable in application, but not without additional research being conducted on combustion phenomenon and cooling requirements.

Gasification of empty fruit bunch with carbon dioxide in an entrained flow gasifier for syngas production

NASA Astrophysics Data System (ADS)

Rahmat, N. F. H.; Rasid, R. A.

2017-06-01

The main objectives of this work are to study the gasification of EFB in an atmospheric entrained flow gasifier, using carbon dioxide (CO2) as its gasifying agent and to determine the optimum gasification operating conditions, which includes temperature and the oxidant to fuel (OTF) ratio. These were evaluated in terms of important gasification parameters such as the concentration of hydrogen (H2) and carbon monoxide (CO) produced the syngas ratio H2/CO and carbon conversion. The gasification reactions take place in the presence of CO2 at very high reaction rate because of the high operating temperature (700°C - 900°C). The use of CO2 as the oxidant for gasification process can improve the composition of syngas produced as in the Boudouard reaction. Rise of reaction temperature which is 900°C will increase the concentration of both H2 & CO by up to 81 and 30 respectively, though their production were decreased after the OTF ratio of 0.6 for temperature 700°C & 800°C and OTF ratio 0.8 for temperature 750°C. The operating temperature must be higher than 850°C to ensure the Boudouard reaction become the more prominent reaction for the biomass gasification. The syngas ratio obtained was in the range of ≈ 0.6 - 2.4 which is sufficient for liquid fuel synthesis. For the carbon conversion, the highest fuel conversion recorded at temperature 850°C for all OTF ratios. As the OTF ratio increases, it was found that there was an increase in the formation of CO and H2. This suggests that to achieve higher carbon conversion, high operating temperature and OTF ratio are preferable. This study provides information on the optimum operating conditions for the gasification of biomass, especially the EFB, hence may upsurge the utilization of biomass waste as an energy source.

Understanding patterns of land-cover change in the Brazilian Cerrado from 2000 to 2015.

PubMed

Espírito-Santo, Mário M; Leite, Marcos E; Silva, Jhonathan O; Barbosa, Rômulo S; Rocha, André M; Anaya, Felisa C; Dupin, Mariana G V

2016-09-19

Clearing tropical vegetation impacts biodiversity, the provision of ecosystem services, and thus ultimately human welfare. We quantified changes in land cover from 2000 to 2015 across the Cerrado biome of northern Minas Gerais state, Brazil. We assessed the potential biophysical and socio-economic drivers of the loss of Cerrado, natural regeneration and net cover change at the municipality level. Further, we evaluated correlations between these land change variables and indicators of human welfare. We detected extensive land-cover changes in the study area, with the conversion of 23 446 km(2) and the natural regeneration of 13 926 km(2), resulting in a net loss of 9520 km(2) The annual net loss (-1.2% per year) of the cover of Cerrado is higher than that reported for the whole biome in similar periods. We argue that environmental and economic variables interact to underpin rates of conversion of Cerrado, most severely affecting more humid Cerrado lowlands. While rates of Cerrado regeneration are important for conservation strategies of the remaining biome, their integrity must be investigated given the likelihood of encroachment. Given the high frequency of land abandonment in tropical regions, secondary vegetation is fundamental to maintain biodiversity and ecosystem services. Finally, the impacts of Cerrado conversion on human welfare likely vary from local to regional scales, making it difficult to elaborate land-use policies based solely on socio-economic indicators.This article is part of the themed issue 'Tropical grassy biomes: linking ecology, human use and conservation'. © 2016 The Author(s).

Impedance changes during setting of amorphous calcium phosphate composites.

PubMed

Par, Matej; Šantić, Ana; Gamulin, Ozren; Marovic, Danijela; Moguš-Milanković, Andrea; Tarle, Zrinka

2016-11-01

To investigate the electrical properties of experimental light-curable composite materials based on amorphous calcium phosphate (ACP) with the admixture of silanized barium glass and silica fillers. Short-term setting was investigated by impedance measurements at a frequency of 1kHz, while for the long-term setting the impedance spectra were measured consecutively over a frequency range of 0.05Hz to 1MHz for 24h. The analysis of electrical resistivity changes during curing allowed the extraction of relevant kinetic parameters. The impedance results were correlated to the degree of conversion assessed by Raman spectroscopy, water content determined by gravimetry, light transmittance measured by CCD spectrometer and microstructural features observed by scanning electron microscopy. ACP-based composites have shown higher immediate degree of conversion and less post-cure polymerization than the control composites, but lower polymerization rate. The polymerization rate assessed by impedance measurements correlated well with the light transmittance. The differences in the electrical conductivity values observed among the materials were correlated to the amount of water introduced into composites by the ACP filler. High correlation was found between the degree of conversion and electrical resistivity. Equivalent circuit modeling revealed two electrical contributions for the ACP-based composites and a single contribution for the control composites. The impedance spectroscopy has proven a valuable method for gaining insight into various features of ACP-based composites. Better understanding of the properties of ACP-based composites should further the development of these promising bioactive materials. Copyright © 2016 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Cropland expansion changes deforestation dynamics in the southern Brazilian Amazon

PubMed Central

Morton, Douglas C.; DeFries, Ruth S.; Shimabukuro, Yosio E.; Anderson, Liana O.; Arai, Egidio; del Bon Espirito-Santo, Fernando; Freitas, Ramon; Morisette, Jeff

2006-01-01

Intensive mechanized agriculture in the Brazilian Amazon grew by >3.6 million hectares (ha) during 2001–2004. Whether this cropland expansion resulted from intensified use of land previously cleared for cattle ranching or new deforestation has not been quantified and has major implications for future deforestation dynamics, carbon fluxes, forest fragmentation, and other ecosystem services. We combine deforestation maps, field surveys, and satellite-based information on vegetation phenology to characterize the fate of large (>25-ha) clearings as cropland, cattle pasture, or regrowing forest in the years after initial clearing in Mato Grosso, the Brazilian state with the highest deforestation rate and soybean production since 2001. Statewide, direct conversion of forest to cropland totaled >540,000 ha during 2001–2004, peaking at 23% of 2003 annual deforestation. Cropland deforestation averaged twice the size of clearings for pasture (mean sizes, 333 and 143 ha, respectively), and conversion occurred rapidly; >90% of clearings for cropland were planted in the first year after deforestation. Area deforested for cropland and mean annual soybean price in the year of forest clearing were directly correlated (R2 = 0.72), suggesting that deforestation rates could return to higher levels seen in 2003–2004 with a rebound of crop prices in international markets. Pasture remains the dominant land use after forest clearing in Mato Grosso, but the growing importance of larger and faster conversion of forest to cropland defines a new paradigm of forest loss in Amazonia and refutes the claim that agricultural intensification does not lead to new deforestation. PMID:16973742

Understanding patterns of land-cover change in the Brazilian Cerrado from 2000 to 2015

PubMed Central

Leite, Marcos E.; Silva, Jhonathan O.; Barbosa, Rômulo S.; Rocha, André M.; Anaya, Felisa C.; Dupin, Mariana G. V.

2016-01-01

Clearing tropical vegetation impacts biodiversity, the provision of ecosystem services, and thus ultimately human welfare. We quantified changes in land cover from 2000 to 2015 across the Cerrado biome of northern Minas Gerais state, Brazil. We assessed the potential biophysical and socio-economic drivers of the loss of Cerrado, natural regeneration and net cover change at the municipality level. Further, we evaluated correlations between these land change variables and indicators of human welfare. We detected extensive land-cover changes in the study area, with the conversion of 23 446 km2 and the natural regeneration of 13 926 km2, resulting in a net loss of 9520 km2. The annual net loss (−1.2% per year) of the cover of Cerrado is higher than that reported for the whole biome in similar periods. We argue that environmental and economic variables interact to underpin rates of conversion of Cerrado, most severely affecting more humid Cerrado lowlands. While rates of Cerrado regeneration are important for conservation strategies of the remaining biome, their integrity must be investigated given the likelihood of encroachment. Given the high frequency of land abandonment in tropical regions, secondary vegetation is fundamental to maintain biodiversity and ecosystem services. Finally, the impacts of Cerrado conversion on human welfare likely vary from local to regional scales, making it difficult to elaborate land-use policies based solely on socio-economic indicators. This article is part of the themed issue ‘Tropical grassy biomes: linking ecology, human use and conservation’. PMID:27502383

Prevalence and conversion to dementia of Mild Cognitive Impairment in an elderly Italian population.

PubMed

Limongi, Federica; Siviero, Paola; Noale, Marianna; Gesmundo, Antonella; Crepaldi, Gaetano; Maggi, Stefania

2017-06-01

Mild Cognitive Impairment (MCI) represents a significant risk factor for dementia but there are only a few Italian population studies on its prevalence and its rate of conversion to dementia. Aim of this study was to assess the prevalence of MCI, its subtypes, and rates of conversion to dementia 1 year later in an elderly Italian population. The data are based on an Italian multicenter population-based cohort study with both cross-sectional and longitudinal components. Two thousand three hundred thirty-seven individuals over 65 underwent screening, clinical confirmation and 1-year follow-up. The prevalence of MCI was 21.6% and the amnestic multiple domain was the most frequent subtype (63.2%). The conversion rate to dementia was 4.1% and was found only in the amnestic multiple domain and in the unclassifiable subjects, persons with cognitive deficit but neither demented nor with MCI. The prevalence of MCI in this population sample was similar to that found in other population studies using Petersen's modified MCI criteria as well as his original criteria. With regard to conversion to dementia, our results emphasize the importance to better classify the unclassifiable subjects at high risk of progression to dementia and also at risk of being undiagnosed and untreated. MCI is characterized by extreme variability and instability. Data on the prevalence and the rate of conversion from MCI to dementia are difficult to compare given the important differences from study to study especially with regard to the diagnostic criteria utilized and their operationalization.

Evolutionary Stasis in Cycad Plastomes and the First Case of Plastome GC-Biased Gene Conversion

PubMed Central

Wu, Chung-Shien; Chaw, Shu-Miaw

2015-01-01

In angiosperms, gene conversion has been known to reduce the mutational load of plastid genomes (the plastomes). Particularly, more frequent gene conversions in inverted repeat (IR) than in single copy (SC) regions result in contrasting substitution rates between these two regions. However, little has been known about the effect of gene conversion in the evolution of gymnosperm plastomes. Cycads (Cycadophyta) are the second largest gymnosperm group. Evolutionary study of their plastomes is limited to the basal cycad genus, Cycas. In this study, we addressed three questions. 1) Do the plastomes of other cycad genera evolve slowly as previously observed in the plastome of Cycas taitungensis? 2) Do substitution rates differ between their SC and IR regions? And 3) Does gene conversion occur in the cycad plastomes? If yes, is it AT-biased or GC-biased? Plastomes of eight species from other eight genera of cycads were sequenced. These plastomes are highly conserved in genome organization. Excluding ginkgo, cycad plastomes have significantly lower synonymous and nonsynonymous substitution rates than other gymnosperms, reflecting their evolutionary stasis in nucleotide mutations. In the IRs of cycad plastomes, the reduced substitution rates and GC-biased mutations are associated with a GC-biased gene conversion (gBGC) mechanism. Further investigations suggest that in cycads, gBGC is able to rectify plastome-wide mutations. Therefore, this study is the first to uncover the plastomic gBGC in seed plants. We also propose a gBGC model to interpret the dissimilar evolutionary patterns as well as the compositionally biased mutations in the SC and IR regions of cycad plastomes. PMID:26116919

Effect of supplementation on the performance of grazing Belgian Blue double-muscled heifers.

PubMed

Fiems, L O; De Boever, J L; Vanacker, J M

2013-11-01

Six experiments were conducted to investigate the effect of a feed supplement on the performance of grazing Belgian Blue double-muscled (BBDM) heifers with an initial weight and age of 195 ± 43 kg and 190 ± 52 days. Treatments included were: Exp. 1: supplementation with beet pulp (BP): 2 kg/day per head v. ad libitum intake; Exp. 2: supplementation ad libitum with BP v. a mixture of BP and soybean meal (SBM; BP/SBM ratio of 80/20; FW (fresh weight) basis); Exp. 3: supplementation with 4 kg/day per head of a mixture of BP/SBM (80/20; FW basis) v. BP/formaldehyde-treated SBM (BP/FSBM); Exp. 4: supplementation with 4 kg/day per head of a mixture with a similar protein content (125 g DVE per kg dry matter (DM)), consisting of 80/20 BP/SBM v. 92/8 BP/FSBM; Exp. 5: supplementation with 3 kg/day per head of a mixture of BP/SBM (80/20; FW basis) v. BP/DDGS (dried distillers grains and solubles; 70/30, FW basis); and Exp. 6: supplementation with 3 kg/day per head of 80/20 BP/SBM v. maize silage (MS) and SBM, on the basis of a similar protein concentration in the DM as the 80/20 BP/SBM supplement, and fed at a similar amount of DM as in the BP/SBM group. Supplementing BP ad libitum did not affect daily gain (0.54 v. 0.48 kg) and partial feed conversion (3.62 kg on average) compared with 2 kg/day. Supplying SBM besides BP increased growth rate compared with BP (0.87 v. 0.62 kg/day; P < 0.001), but partial feed conversion was similar. Supplying FSBM did not affect growth rate and partial feed conversion (P > 0.10), but blood urea levels were reduced by FSBM (P < 0.05). DDGS tended to increase growth rate (0.77 v. 0.59 kg/day; P < 0.10) compared with BP/SBM, without effect on partial feed conversion. Replacing BP by MS did not affect daily gain, but partial feed conversion tended to be higher (3.21 v. 3.60 kg/kg body weight (BW) gain; P = 0.062). Increasing the supplement (80/20 BP/SBM) level from 3 to 4 kg daily, corresponding to 1.02% and 1.18% of the mean BW, respectively, resulted in a tendency (P = 0.121) for an increased growth rate. Grazing BBDM heifers of <1 year of age necessitate extra protein besides an energy supplement to improve their performance. DDGS can replace SBM and BP can be replaced by MS.

Conversational Behaviors in Youth with High-Functioning ASD and Asperger Syndrome

ERIC Educational Resources Information Center

Paul, Rhea; Orlovski, Stephanie Miles; Marcinko, Hillary Chuba; Volkmar, Fred

2009-01-01

Twenty-nine youth with autism spectrum disorders and 26 with typical development between 12 and 18 years of age were engaged in structured interviews (ADOS). The interviews were videotaped and rated for atypical conversational behaviors by trained raters, using the Pragmatic Rating Scale (Landa et al. "Psychol Med" 22:245-254, 1992). The ASD group…

Effects of Appropriate Prolonged Sacral Neuromodulation Testing in Improving Implantation Rate of a Permanent Implantable Pulse Generator in Patients with Refractory Lower Urinary Tract Dysfunctions in Mainland China.

PubMed

Zhang, Peng; Zhang, Jian-Zhong; Wu, Li-Yang; Zhang, Xiao-Dong

2017-02-20

Sacral neuromodulation (SNM) has become an effective method for treating lower urinary tract voiding dysfunction during the past 20 years. Because of the expensive cost, the number of implantable pulse generator (IPG) implantations per year in China is far lower than that in Western developed countries since 2012. This study was to summarize the effects of the appropriate prolonged SNM testing time in improving the implantation rate of a permanent IPG in patients with refractory lower urinary tract symptoms (LUTS) in mainland China. From January 2013 to June 2016, 51 patients with refractory LUTS received SNM therapy. In this study, we compared the conversion rate 2 weeks after the Stage I test and final actual conversion rate. We also observed the complications (such as pain, infection, and electrode displacement) and effectiveness. We tried to improve an appropriate prolonged test time which was favorable for improving the SNM conversion rate while ensuring safety and effectiveness. Among 51 patients receiving SNM therapy, 19 patients (mean age 45.0 ± 16.9 years) had poor Stage I test results, and on an average, the electrode was removed 27.4 ± 9.6 days after the surgery. In one patient, the electrode was removed within 2 weeks; when the remaining 18 patients were questioned 2 weeks after testing, none of the patients wanted to terminate the test, and all the 18 patients desired to prolong the testing time to further observe the treatment effect. The remaining 32 patients (mean age 46.7 ± 15.3 years) received Stage II permanent implantation at 19.6 ± 10.4 days after the surgery. The overall Stage I-II conversion was 62.7% (32/51) in this study. Within 2 weeks after the surgery, only eight patients received Stage II permanent implantation, and the conversion rate was only 15.7% (8/51), which was much lower than the overall conversion rate of 62.7%. Nearly 84.4% (27/32) of the patients received Stage II implantation within 4 weeks. None of the patients had incision infections. In one patient, the entire system was removed 1 month after Stage II implantation due to pain in the implantation site. Appropriate extension of the Stage I testing time of an SNM-barbed electrode could significantly improve the Stage II permanent implantation rate in Chinese refractory LUTS patients; there were no wound infections, and the postoperative complication rate was low. This study recommended that Stage I period of SNM therapy should be 4 weeks according to safety and successful conversion rate.

Meat-type chickens have a higher efficiency of mitochondrial oxidative phosphorylation than laying-type chickens.

PubMed

Toyomizu, Masaaki; Kikusato, Motoi; Kawabata, Yusuke; Azad, Md Abul Kalam; Inui, Eriko; Amo, Taku

2011-05-01

Meat-type chickens show high feed efficiency and have a very rapid growth rate compared with laying-type chickens. To clarify whether the type-specific difference in feed conversion efficiency is involved in mitochondrial bioenergetics, modular kinetic analysis was applied to oxidative phosphorylation in skeletal muscle mitochondria of both type chickens. Mitochondria from skeletal muscle of meat-type chickens showed greater substrate oxidation and phosphorylating activities, and less proton leak than those of the laying-type, resulting in a higher efficiency of oxidative phosphorylation. Gene expression and protein content of uncoupling protein (avUCP) but not adenine nucleotide translocase (avANT) gene expression were lower in skeletal muscle mitochondria of meat-type chickens than the laying-type. The current results regarding a higher efficiency of oxidative phosphorylation and UCP content may partially support the high feed efficiency of meat-type chickens. Copyright © 2011 Elsevier Inc. All rights reserved.

Switch from epoetin to darbepoetin alfa in hemodialysis: dose equivalence and hemoglobin stability.

PubMed

Arrieta, Javier; Moina, Iñigo; Molina, José; Gallardo, Isabel; Muñiz, María Luisa; Robledo, Carmen; García, Oscar; Vidaur, Fernando; Muñoz, Rosa Inés; Iribar, Izaskun; Aguirre, Román; Maza, Antonio

2014-01-01

The objective of the study reported here was to describe dose equivalence and hemoglobin (Hb) stability in a cohort of unselected hemodialysis patients who were switched simultaneously from epoetin alfa to darbepoetin alfa. This was a multicenter, observational, retrospective study in patients aged ≥18 years who switched from intravenous (IV) epoetin alfa to IV darbepoetin alfa in October 2007 (Month 0) and continued on hemodialysis for at least 24 months. The dose was adjusted to maintain Hb within 1.0 g/dL of baseline. We included 125 patients (59.7% male, mean [standard deviation (SD)] age 70.4 [13.4] years). No significant changes were observed in Hb levels (mean [SD] 11.9 [1.3] g/dL, 12.0 [1.5], 12.0 [1.5], and 12.0 [1.7] at Months -12, 0, 12 and 24, respectively, P=0.409). After conversion, the erythropoiesis-stimulating agent (ESA) dose decreased significantly (P<0.0001), with an annual mean of 174.7 (88.7) international units (IU)/kg/week for epoetin versus 95.7 (43.4) (first year) and 91.4 (42.7) IU/kg/week (second year) for darbepoetin (65% and 64% reduction, respectively). The ESA resistance index decreased from 15.1 (8.5) IU/kg/week/g/dL with epoetin to 8.1 (3.9) (first year) and 7.9 (4.0) (second year) with darbepoetin (P<0.0001). The conversion rate was 354:1 in patients requiring high (>200 IU/kg/week) doses of epoetin and 291:1 in patients requiring low doses. In patients on hemodialysis receiving ESAs, conversion from epoetin alfa to darbepoetin alfa was associated with an approximate and persistent reduction of 65% of the required dose. To maintain Hb stability, a conversion rate of 300:1 seems to be appropriate for most patients receiving low doses of epoetin alfa (≤200 IU/kg/week), while 350:1 would be better for patients receiving higher doses.

The clinical efficacy of a clarithromycin-based regimen for Mycobacterium avium complex disease: A nationwide post-marketing study.

PubMed

Kadota, Jun-Ichi; Kurashima, Atsuyuki; Suzuki, Katsuhiro

2017-05-01

The revised 2007 American Thoracic Society/Infectious Diseases Society of America statement recommend clarithromycin-based combination therapy for treatment of Mycobacterium avium complex lung disease and stipulates approximately 1 year of continuous treatment after bacilli negative conversion. However, supporting data are insufficient. Our objective was to obtain data on the clinical outcome of clarithromycin-based daily regimens by conducting a nationwide retrospective post-marketing study of M. avium complex lung disease. In accordance with the Japanese guidelines, patients were enrolled in this survey according to their chest radiographic findings and microbiologic test results. They were treated with a multidrug regimen including clarithromycin, rifampicin, and ethambutol (clarithromycin-based regimen) until bacilli negative conversion, and the treatment was continued for approximately 1 year after the initial conversion. Data were collected before administration, at the time of bacilli negative conversion, at the end of treatment, and at 6 months after the end of treatment. Of the 466 subjects enrolled in the study, 271 patients who received clarithromycin at 800 mg/day underwent evaluation for M. avium complex disease. The final bacilli negative conversion rate in those patients was 94.7%. The bacteriological relapse rate was 5.0% (5/100 patients). Bacteriological relapse was noted in patients treated for less than 15 months after conversion. No life-threatening or serious adverse drug reactions were observed. This study demonstrated that a clarithromycin-based daily regimen can yield a high bacteriological conversion rate in M. avium complex disease. After conversion, treatment for less than 15 months might be insufficient to prevent bacteriological relapse. Copyright © 2017 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Biogeochemistry of the Amazon River Basin: the role of aquatic ecosystems in the Amazon functioning

NASA Astrophysics Data System (ADS)

Victoria, R. L.; Ballester, V. R.; Krushe, A. V.; Richey, J. E.; Aufdenkampe, A. K.; Kavaguishi, N. L.; Gomes, B. M.; Victoria, D. D.; Montebello, A. A.; Niell, C.; Deegan, L.

2004-12-01

In this study we present the results of an integrated analysis of physical and anthropogenic controls of river biogeochemistry in Amazônia. At the meso-scale level, our results show that both soil properties and land use are the main drivers of river biogeochemistry and metabolism, with pasture cover and soil exchange cation capacity explaining 99% (p < 0.01) of the variability observed in surface water ions and nutrients concentrations. In small rivers, forest clearing can increase cations, P and C inputs. P and light are the main PPL limiting factors in forested streams, while in pasture streams N becomes limiting. P export to streams may increase or remain nearly undetectable after forest-to-pasture conversion, depending on soil type. Pasture streams on Oxisols have very low P export, while on Ultisols P export is increased. Conversions of forest to pasture leads to extensive growth of in channel Paspalum resulting in higher DOC concentrations and respiration rates. Pasture streams have higher DOC fluxes when compared to the forest ones. In pasture areas the soil are compacted, there is less infiltration and higher surface run off, leaching soil superficial layers and caring more DOC to the streams. In forest areas infiltration is deeper into the soils and canopy interaction is higher. Mineralogy and soil properties are key factors determining exports of nutrients to streams. Therefore, land use change effects on nutrient export from terrestrial to aquatic ecosystems and the atmosphere must be understood within the context of varying soil properties across the Amazon Basin.

[Effect of biological pretreatment with Trametes vesicolor on the enzymatic hydrolysis of softwood and hardwood].

PubMed

Yu, Hongbo; Zhang, Xiaoyu

2009-07-01

We evaluated the effect of biological pretreatment with white rot fungus Trametes vesicolor on the enzymatic hydrolysis of two wood species, Chinese willow (Salix babylonica, hardwood) and China-fir (Cunninghamia lanceolata, softwood). The result indicated that the pretreated woods showed significant increases in the final conversion ratios of enzymatic hydrolysis (4.78-fold for hardwood and 4.02-fold for softwood). In order to understand the role of biological pretreatment we investigated the enzyme-substrate interactions. Biological pretreatment enhanced the substrate accessibility to cellulase but not always correlated with the initial conversion rate. However, the change of the conversion rate decreased dramatically with increased desorption values after biological pretreatment. Thus, the biological pretreatment slowed down the declines in conversion rates during enzymatic hydrolysis by reducing the irreversible adsorption of cellulase and then improved the enzymatic hydrolysis. Moreover, the decreases of the irreversible adsorption may be attributed to the partial lignin degradation and alteration in lignin structure after biological pretreatment.

Continuous production of lipase-catalyzed biodiesel in a packed-bed reactor: optimization and enzyme reuse study.

PubMed

Chen, Hsiao-Ching; Ju, Hen-Yi; Wu, Tsung-Ta; Liu, Yung-Chuan; Lee, Chih-Chen; Chang, Cheng; Chung, Yi-Lin; Shieh, Chwen-Jen

2011-01-01

An optimal continuous production of biodiesel by methanolysis of soybean oil in a packed-bed reactor was developed using immobilized lipase (Novozym 435) as a catalyst in a tert-butanol solvent system. Response surface methodology (RSM) and Box-Behnken design were employed to evaluate the effects of reaction temperature, flow rate, and substrate molar ratio on the molar conversion of biodiesel. The results showed that flow rate and temperature have significant effects on the percentage of molar conversion. On the basis of ridge max analysis, the optimum conditions were as follows: flow rate 0.1 mL/min, temperature 52.1°C, and substrate molar ratio 1 : 4. The predicted and experimental values of molar conversion were 83.31 ± 2.07% and 82.81 ± .98%, respectively. Furthermore, the continuous process over 30 days showed no appreciable decrease in the molar conversion. The paper demonstrates the applicability of using immobilized lipase and a packed-bed reactor for continuous biodiesel synthesis.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Makarov, Nikolay S.; Lin, Qianglu; Pietryga, Jeffrey M.

One source of efficiency losses in photovoltaic cells is their transparency toward solar photons with energies below the band gap of the absorbing layer. This loss can be reduced using a process of up-conversion whereby two or more sub-band-gap photons generate a single above-gap exciton. Traditional approaches to up-conversion, such as nonlinear two-photon absorption (2PA) or triplet fusion, suffer from low efficiency at solar light intensities, a narrow absorption bandwidth, nonoptimal absorption energies, and difficulties for implementing in practical devices. We show that these deficiencies can be alleviated using the effect of Auger up-conversion in thick-shell PbSe/CdSe quantum dots. Thismore » process relies on Auger recombination whereby two low-energy, core-based excitons are converted into a single higher-energy, shell-based exciton. When compared to their monocomponent counterparts, the tailored PbSe/CdSe heterostructures feature enhanced absorption cross-sections, a higher efficiency of the “productive” Auger pathway involving re-excitation of a hole, and longer lifetimes of both core- and shell-localized excitons. These features lead to effective up-conversion cross-sections that are more than 6 orders of magnitude higher than for standard nonlinear 2PA, which allows for efficient up-conversion of continuous wave infrared light at intensities as low as a few watts per square centimeter.« less

Pharmacologic Conversion during Dofetilide Treatment for Persistent Atrial Fibrillation.

PubMed

Steinberg, Jonathan S; Shah, Yash; Szepietowska, Barbara

2017-06-01

Dofetilide is a pure I Kr blocker and is one of the few drugs specifically studied and approved in the United States for the management of persistent atrial fibrillation (AF). Dofetilide has been noted to have a high rate of pharmacologic conversion during initial dosing in prior smaller studies. The intent of the study was to examine the safety of an inpatient loading strategy, and the incidence and patterns of pharmacologic conversion by dofetilide during the treatment of persistent AF in a large consecutive cohort. This is a retrospective analysis of 308 consecutive patients with persistent AF electively admitted for inpatient dofetilide loading. The initiation dose of dofetilide was determined by the creatinine clearance. Overall, 88% (n = 271) successfully completed initiation of dofetilide and were discharged in sinus rhythm. The most common reason for failure to complete initiation of dofetilide loading was QTc prolongation in 24 patients (7.8%), and torsade de pointes occurred in three patients (1%). Pharmacologic conversion was observed in 56% (n = 151) after a median of two doses. The rate of pharmacologic conversion based on the final dose was 75%, 9%, and 0% for 500 mcg, 250 mcg, and 125 mcg, respectively (P < 0.05). Dofetilide is a well-tolerated antiarrhythmic drug with a low incidence of proarrhythmia and an especially high rate of pharmacologic conversion in patients with persistent AF. © 2017 Wiley Periodicals, Inc.

Alexithymia in patients with conversion disorder.

PubMed

Gulpek, Demet; Kelemence Kaplan, Figen; Kesebir, Sermin; Bora, Ozlem

2014-07-01

In the recent years, it has been observed that alexithymia is not specified for the psychosomatic disorders. It is known that alexithymia is observed frequently in various psychiatric disorders especially in the somatoform disorders. The aim of this study is to evaluate alexithymia in the patients with the conversion disorder. The study was performed in the Psychiatry Outpatients Clinics of the Izmir Atatürk Training and Research Hospital and Erenköy Psychiatry Education and Research Hospital. A total of 93 cases-47 outpatients who were diagnosed with conversion disorder according to the DSM-IV criteria and 46 age, gender and educational level matched healthy controls-were included in the study. All the cases were assessed by a Structured Clinical Interview for DSM-IV and were evaluated with a questionnaire (which included demographics and clinical data), the Toronto Alexithymia Scale and the Somatosensory Amplification Scale. When the two groups were compared, the Toronto Alexithymia Scale scores (except "externally oriented thinking" subscale) and the Somatosensory Amplification Scale score of the conversion disorder group were statistically significantly higher than the control group. The number of the alexithymic cases of the patient group was significantly higher than the control group's. The level of alexithymia in conversion disorder patients, without any other psychiatric disorder, is higher than that of the healthy controls. During the evaluation of the psychological state of patients with conversion disorder, it could be useful to keep in mind the probability of them having alexithymia to determine the type of suitable therapy.

Massachusetts Lowell low speed wind tunnel (LSWT) test section

NASA Astrophysics Data System (ADS)

Anderson, Erik William

The alumina and hybrid alumina-silica FT catalyst were prepared by one-step solgel/oil-drop methods using metal-nitrate-solutions (method-I), and nanoparticle-metaloxides (method-2). The nanoparticle-metal-oxides did not participate in solubility equilibria in contrast to metal nitrate in method-1 causing no metal ion seepage; therefore, method-2 yields higher XRF metal loading efficiency than method-1. The thermal analysis confirmed that the metal loading by method-1 and method-2 involved two different pathways. Method-1 involves solubility equilibria in the conversion of metal-nitrate to metal- hydroxide and finally to metal-oxide, while in method-2 nanoparticle-metal-oxide remained intact during sol-gel-oil-drop and calcination steps. The alumina supported catalysts were dominated by gamma-alumina PXRD peaks in alumina catalysts while amorphous alumino-silicate phase was the bulk of hybrid alumina-silica catalysts. The presence of cobalt oxides (CoO, Co3O4) and iron oxides (FeO, Fe2O3) phases are confirmed in the catalysts prepared by method-1 and method-2. The PXRD analysis indicated weak peak intensities in catalysts with 5 wt. % total metal loading. PXRD pattern confirmed alloy formation in the bimetallic catalysts (CoFe2O4) on alumina support phase gamma-A12 O3. The surface area and pore diameter of hybrid alumina-silica granules (301 - 372 m2/g and 7.3 nm) showed better values than the alumina granules (251 - 256 m2/g and 6.5 nm). The support pore diameter of both types of granules is within the mesoporous range (1 - 50 nm). The morphology of all the catalysts is preserved upon metal loading and heat treatments. The surface characteristics of the sol-gel-oil-drop method prepared catalysts indicate there was no significant pore blockage of the support below 10 wt % total metal loading. The CO conversion of the FT catalysts was measured to screen catalytic active metals and determine the optimum temperatures of the FT reaction for the alumina catalysts. The alumina FT catalysts showed an optimum reaction temperature of 250 °C. Hydrocarbon production and CO conversion of alumina and hybrid alumina-silica FT catalysts were investigated. Among monometallic alumina catalysts, Co(5%) showed a higher CO conversion. The incorporation of Fe to Co increased CO conversion and hydrocarbon production. Increased Fe content in the bimetallic catalysts prepared by combined method-1&2, decreased CO conversion and hydrocarbon production, and increased CO 2 production. The bimetallic nano-Co(2.5%)nano-Fe(2.5%) prepared by method-2 alone showed higher CO conversion comparable to the Co(4%)nano-Fe(l %). Hybrid alumina-silica FT catalysts showed a higher CO conversion than the alumina FT catalysts due to better surface characteristics. The monometallic catalysts showed higher selectivity to C1-C4 hydrocarbon than bimetallic. The bimetallic alumina FT catalysts prepared by method-2 showed slightly higher C5+ selectivity compared to the higher Co catalysts prepared by combined method- I &2. The Ru promotion showed a significant effect on the CO conversion and 11 product distribution of the monometallic catalysts. There was no significant effect on the CO conversion on the (Co-Fe) bimetallic catalysts, but hydrocarbon production slightly increased when promoted by 0.5 wt.% Ru.

Synthesis, characterization, and activity of Co/Fe alumina/silica supported Ft catalysts and the study of promoter effect of ruthenium

NASA Astrophysics Data System (ADS)

Esumike, Sunday Azubike

The alumina and hybrid alumina-silica FT catalyst were prepared by one-step solgel/oil-drop methods using metal-nitrate-solutions (method-I), and nanoparticle-metaloxides (method-2). The nanoparticle-metal-oxides did not participate in solubility equilibria in contrast to metal nitrate in method-1 causing no metal ion seepage; therefore, method-2 yields higher XRF metal loading efficiency than method-1. The thermal analysis confirmed that the metal loading by method-1 and method-2 involved two different pathways. Method-1 involves solubility equilibria in the conversion of metal-nitrate to metal- hydroxide and finally to metal-oxide, while in method-2 nanoparticle-metal-oxide remained intact during sol-gel-oil-drop and calcination steps. The alumina supported catalysts were dominated by gamma-alumina PXRD peaks in alumina catalysts while amorphous alumino-silicate phase was the bulk of hybrid alumina-silica catalysts. The presence of cobalt oxides (CoO, Co3O4) and iron oxides (FeO, Fe2O3) phases are confirmed in the catalysts prepared by method-1 and method-2. The PXRD analysis indicated weak peak intensities in catalysts with 5 wt. % total metal loading. PXRD pattern confirmed alloy formation in the bimetallic catalysts (CoFe2O4) on alumina support phase gamma-A12 O3. The surface area and pore diameter of hybrid alumina-silica granules (301 - 372 m2/g and 7.3 nm) showed better values than the alumina granules (251 - 256 m2/g and 6.5 nm). The support pore diameter of both types of granules is within the mesoporous range (1 - 50 nm). The morphology of all the catalysts is preserved upon metal loading and heat treatments. The surface characteristics of the sol-gel-oil-drop method prepared catalysts indicate there was no significant pore blockage of the support below 10 wt % total metal loading. The CO conversion of the FT catalysts was measured to screen catalytic active metals and determine the optimum temperatures of the FT reaction for the alumina catalysts. The alumina FT catalysts showed an optimum reaction temperature of 250 °C. Hydrocarbon production and CO conversion of alumina and hybrid alumina-silica FT catalysts were investigated. Among monometallic alumina catalysts, Co(5%) showed a higher CO conversion. The incorporation of Fe to Co increased CO conversion and hydrocarbon production. Increased Fe content in the bimetallic catalysts prepared by combined method-1&2, decreased CO conversion and hydrocarbon production, and increased CO 2 production. The bimetallic nano-Co(2.5%)nano-Fe(2.5%) prepared by method-2 alone showed higher CO conversion comparable to the Co(4%)nano-Fe(l %). Hybrid alumina-silica FT catalysts showed a higher CO conversion than the alumina FT catalysts due to better surface characteristics. The monometallic catalysts showed higher selectivity to C1-C4 hydrocarbon than bimetallic. The bimetallic alumina FT catalysts prepared by method-2 showed slightly higher C5+ selectivity compared to the higher Co catalysts prepared by combined method- I &2. The Ru promotion showed a significant effect on the CO conversion and 11 product distribution of the monometallic catalysts. There was no significant effect on the CO conversion on the (Co-Fe) bimetallic catalysts, but hydrocarbon production slightly increased when promoted by 0.5 wt.% Ru.

Influence of operating pressure on the biological hydrogen methanation in trickle-bed reactors.

PubMed

Ullrich, Timo; Lindner, Jonas; Bär, Katharina; Mörs, Friedemann; Graf, Frank; Lemmer, Andreas

2018-01-01

In order to investigate the influence of pressures up to 9bar absolute on the productivity of trickle-bed reactors for biological methanation of hydrogen and carbon dioxide, experiments were carried out in a continuously operated experimental plant with three identical reactors. The pressure increase promises a longer residence time and improved mass transfer of H 2 due to higher gas partial pressures. The study covers effects of different pressures on important parameters like gas hourly space velocity, methane formation rate, conversion rates and product gas quality. The methane content of 64.13±3.81vol-% at 1.5bar could be increased up to 86.51±0.49vol-% by raising the pressure to 9bar. Methane formation rates of up to 4.28±0.26m 3 m -3 d -1 were achieved. Thus, pressure increase could significantly improve reactor performance. Copyright © 2017 Elsevier Ltd. All rights reserved.

Transesterification of rapeseed oil for biodiesel production in trickle-bed reactors packed with heterogeneous Ca/Al composite oxide-based alkaline catalyst.

PubMed

Meng, Yong-Lu; Tian, Song-Jiang; Li, Shu-Fen; Wang, Bo-Yang; Zhang, Min-Hua

2013-05-01

A conventional trickle bed reactor and its modified type both packed with Ca/Al composite oxide-based alkaline catalysts were studied for biodiesel production by transesterification of rapeseed oil and methanol. The effects of the methanol usage and oil flow rate on the FAME yield were investigated under the normal pressure and methanol boiling state. The oil flow rate had a significant effect on the FAME yield for the both reactors. The modified trickle bed reactor kept over 94.5% FAME yield under 0.6 mL/min oil flow rate and 91 mL catalyst bed volume, showing a much higher conversion and operational stability than the conventional type. With the modified trickle bed reactor, both transesterification and methanol separation could be performed simultaneously, and glycerin and methyl esters were separated additionally by gravity separation. Copyright © 2013 Elsevier Ltd. All rights reserved.

Bio-oil production from fast pyrolysis of waste furniture sawdust in a fluidized bed.

PubMed

Heo, Hyeon Su; Park, Hyun Ju; Park, Young-Kwon; Ryu, Changkook; Suh, Dong Jin; Suh, Young-Woong; Yim, Jin-Heong; Kim, Seung-Soo

2010-01-01

The amount of waste furniture generated in Korea was over 2.4 million tons in the past 3 years, which can be used for renewable energy or fuel feedstock production. Fast pyrolysis is available for thermo-chemical conversion of the waste wood mostly into bio-oil. In this work, fast pyrolysis of waste furniture sawdust was investigated under various reaction conditions (pyrolysis temperature, particle size, feed rate and flow rate of fluidizing medium) in a fluidized-bed reactor. The optimal pyrolysis temperature for increased yields of bio-oil was 450 degrees C. Excessively smaller or larger feed size negatively affected the production of bio-oil. Higher flow and feeding rates were more effective for the production of bio-oil, but did not greatly affect the bio-oil yields within the tested ranges. The use of product gas as the fluidizing medium had a potential for increased bio-oil yields.

Application of Flexible Micro Temperature Sensor in Oxidative Steam Reforming by a Methanol Micro Reformer

PubMed Central

Lee, Chi-Yuan; Lee, Shuo-Jen; Shen, Chia-Chieh; Yeh, Chuin-Tih; Chang, Chi-Chung; Lo, Yi-Man

2011-01-01

Advances in fuel cell applications reflect the ability of reformers to produce hydrogen. This work presents a flexible micro temperature sensor that is fabricated based on micro-electro-mechanical systems (MEMS) technology and integrated into a flat micro methanol reformer to observe the conditions inside that reformer. The micro temperature sensor has higher accuracy and sensitivity than a conventionally adopted thermocouple. Despite various micro temperature sensor applications, integrated micro reformers are still relatively new. This work proposes a novel method for integrating micro methanol reformers and micro temperature sensors, subsequently increasing the methanol conversion rate and the hydrogen production rate by varying the fuel supply rate and the water/methanol ratio. Importantly, the proposed micro temperature sensor adequately controls the interior temperature during oxidative steam reforming of methanol (OSRM), with the relevant parameters optimized as well. PMID:22319407

Retrospective Conversion at a Two-Year College.

ERIC Educational Resources Information Center

Krieger, Michael T.

1982-01-01

Findings of a project to convert a single LC class from cards to machine readable tapes at a two-year college suggest that an in-house retrospective conversion is feasible for academic libraries. A high conversion hit rate, implying minimal original cataloging, will keep project costs and duration low. There are five references. (RAA)

5 CFR 531.217 - Special conversion rules for certain non-GS employees.

Code of Federal Regulations, 2012 CFR

2012-01-01

... be converted to GS-equivalent rates immediately before leaving the non-GS system, the employee is... 5 Administrative Personnel 1 2012-01-01 2012-01-01 false Special conversion rules for certain non... Appointment Or Position Changes § 531.217 Special conversion rules for certain non-GS employees. When an...

5 CFR 531.217 - Special conversion rules for certain non-GS employees.

Code of Federal Regulations, 2014 CFR

2014-01-01

... be converted to GS-equivalent rates immediately before leaving the non-GS system, the employee is... 5 Administrative Personnel 1 2014-01-01 2014-01-01 false Special conversion rules for certain non... Appointment Or Position Changes § 531.217 Special conversion rules for certain non-GS employees. When an...

5 CFR 531.217 - Special conversion rules for certain non-GS employees.

Code of Federal Regulations, 2011 CFR

2011-01-01

... be converted to GS-equivalent rates immediately before leaving the non-GS system, the employee is... 5 Administrative Personnel 1 2011-01-01 2011-01-01 false Special conversion rules for certain non... Appointment Or Position Changes § 531.217 Special conversion rules for certain non-GS employees. When an...

5 CFR 531.217 - Special conversion rules for certain non-GS employees.

Code of Federal Regulations, 2013 CFR

2013-01-01

... be converted to GS-equivalent rates immediately before leaving the non-GS system, the employee is... 5 Administrative Personnel 1 2013-01-01 2013-01-01 false Special conversion rules for certain non... Appointment Or Position Changes § 531.217 Special conversion rules for certain non-GS employees. When an...

5 CFR 531.217 - Special conversion rules for certain non-GS employees.

Code of Federal Regulations, 2010 CFR

2010-01-01

... be converted to GS-equivalent rates immediately before leaving the non-GS system, the employee is... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Special conversion rules for certain non... Appointment Or Position Changes § 531.217 Special conversion rules for certain non-GS employees. When an...

Mechanism of nuclear spin initiated para-H2 to ortho-H2 conversion.

PubMed

Buntkowsky, G; Walaszek, B; Adamczyk, A; Xu, Y; Limbach, H-H; Chaudret, B

2006-04-28

In this paper a quantitative explanation for a diamagnetic ortho/para H2 conversion is given. The description is based on the quantum-mechanical density matrix formalism originally developed by Alexander and Binsch for studies of exchange processes in NMR spectra. Only the nuclear spin system is treated quantum-mechanically. Employing the model of a three spin system, the reactions of the hydrogen gas with the catalysts are treated as a phenomenological rate process, described by a rate constant. Numerical calculations reveal that for nearly all possible geometrical arrangements of the three spin system an efficient spin conversion is obtained. Only in the chemically improbable case of a linear group H-X-H no spin conversion is obtained. The efficiency of the spin conversion depends strongly on the lifetime of the H-X-H complex and on the presence of exchange interactions between the two hydrogens. Even moderate exchange couplings cause a quench of the spin conversion. Thus a sufficiently strong binding of the dihydrogen to the S spin is necessary to render the quenching by the exchange interaction ineffective.

Particulate matter is associated with sputum culture conversion in patients with culture-positive tuberculosis.

PubMed

Chen, Kuan-Yuan; Chuang, Kai-Jen; Liu, Hui-Chiao; Lee, Kang-Yun; Feng, Po-Hao; Su, Chien-Ling; Lin, Chii-Lan; Lee, Chun-Nin; Chuang, Hsiao-Chi

2016-01-01

Emerging risk factors for tuberculosis (TB) infection, such as air pollution, play a significant role at both the individual and population levels. However, the association between air pollution and TB remains unclear. The objective of this study was to examine the association between outdoor air pollution and sputum culture conversion in TB patients. In the present study, 389 subjects were recruited from a hospital in Taiwan from 2010 to 2012: 144 controls with non-TB-related pulmonary diseases with negative sputum cultures and 245 culture-positive TB subjects. We observed that a 1 μg/m(3) increase in particulate matter of ≤10 μm in aerodynamic diameter (PM10) resulted in 4% higher odds of TB (odds ratio =1.04, 95% confidence interval =1.01-1.08, P<0.05). The chest X-ray grading of TB subjects was correlated to 1 year levels of PM10 (R (2)=0.94, P<0.05). However, there were no associations of pulmonary cavitation or treatment success rate with PM10. In subjects with TB-positive cultures, annual exposure to ≥50 μg/m(3) PM10 was associated with an increase in the time required for sputum culture conversion (hazard ratio =1.28, 95% confidence interval: 1.07-1.84, P<0.05). In conclusion, chronic exposure to ≥50 μg/m(3) PM10 may prolong the sputum culture conversion of TB patients with sputum-positive cultures.

Perioperative outcomes of video- and robot-assisted segmentectomies.

PubMed

Rinieri, Philippe; Peillon, Christophe; Salaün, Mathieu; Mahieu, Julien; Bubenheim, Michael; Baste, Jean-Marc

2016-02-01

Video-assisted thoracic surgery appears to be technically difficult for segmentectomy. Conversely, robotic surgery could facilitate the performance of segmentectomy. The aim of this study was to compare the early results of video- and robot-assisted segmentectomies. Data were collected prospectively on videothoracoscopy from 2010 and on robotic procedures from 2013. Fifty-one patients who were candidates for minimally invasive segmentectomy were included in the study. Perioperative outcomes of video-assisted and robotic segmentectomies were compared. The minimally invasive segmentectomies included 32 video- and 16 robot-assisted procedures; 3 segmentectomies (2 video-assisted and 1 robot-assisted) were converted to lobectomies. Four conversions to thoracotomy were necessary for anatomical reason or arterial injury, with no uncontrolled bleeding in the robotic arm. There were 7 benign or infectious lesions, 9 pre-invasive lesions, 25 lung cancers, and 10 metastatic diseases. Patient characteristics, type of segment, conversion to thoracotomy, conversion to lobectomy, operative time, postoperative complications, chest tube duration, postoperative stay, and histology were similar in the video and robot groups. Estimated blood loss was significantly higher in the video group (100 vs. 50 mL, p = 0.028). The morbidity rate of minimally invasive segmentectomy was low. The short-term results of video-assisted and robot-assisted segmentectomies were similar, and more data are required to show any advantages between the two techniques. Long-term oncologic outcomes are necessary to evaluate these new surgical practices. © The Author(s) 2016.

Metabolic Response of “Candidatus Accumulibacter Phosphatis” Clade II C to Changes in Influent P/C Ratio

PubMed Central

Welles, Laurens; Abbas, Ben; Sorokin, Dimitry Y.; Lopez-Vazquez, Carlos M.; Hooijmans, Christine M.; van Loosdrecht, Mark C. M.; Brdjanovic, Damir

2017-01-01

The objective of this study was to investigate the ability of a culture highly enriched with the polyphosphate-accumulating organism, “Candidatus Accumulibacter phosphatis” clade IIC, to adjust their metabolism to different phosphate availabilities. For this purpose the biomass was cultivated in a sequencing batch reactor with acetate and exposed to different phosphate/carbon influent ratios during six experimental phases. Activity tests were conducted to determine the anaerobic kinetic and stoichiometric parameters as well as the composition of the microbial community. Increasing influent phosphate concentrations led to increased poly-phosphate content and decreased glycogen content of the biomass. In response to higher biomass poly-phosphate content, the biomass showed higher specific phosphate release rates. Together with the phosphate release rates, acetate uptake rates also increased up to an optimal poly-phosphate/glycogen ratio of 0.3 P-mol/C-mol. At higher poly-phosphate/glycogen ratios (obtained at influent P/C ratios above 0.051 P-mol/C-mol), the acetate uptake rates started to decrease. The stoichiometry of the anaerobic conversions clearly demonstrated a metabolic shift from a glycogen dominated to a poly-phosphate dominated metabolism as the biomass poly-phosphate content increased. FISH and DGGE analyses confirmed that no significant changes occurred in the microbial community, suggesting that the changes in the biomass activity were due to different metabolic behavior, allowing the organisms to proliferate under conditions with fluctuating phosphate levels. PMID:28111570