IBS for non-gaussian distributions

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

Fedotov, A.; Sidorin, A.O.; Smirnov, A.V.

In many situations distribution can significantly deviate from Gaussian which requires accurate treatment of IBS. Our original interest in this problem was motivated by the need to have an accurate description of beam evolution due to IBS while distribution is strongly affected by the external electron cooling force. A variety of models with various degrees of approximation were developed and implemented in BETACOOL in the past to address this topic. A more complete treatment based on the friction coefficient and full 3-D diffusion tensor was introduced in BETACOOL at the end of 2007 under the name 'local IBS model'. Suchmore » a model allowed us calculation of IBS for an arbitrary beam distribution. The numerical benchmarking of this local IBS algorithm and its comparison with other models was reported before. In this paper, after briefly describing the model and its limitations, they present its comparison with available experimental data.« less

The Role of Genetics in IBS

PubMed Central

Saito, Yuri A.

2011-01-01

IBS is a common disorder that has been shown to aggregate in families, to affect multiple generations, but not in a manner consistent with a major Mendelian effect. Relatives of an individual with IBS are two to three times as likely to have IBS, with both genders being affected. The estimated genetic liability ranges between 1–20%, with heritability estimates ranging between 0–57%. Although the role of childhood events such as nasogastric tube placement, poor nutrition, abuse, and other stressors have been clearly associated with IBS, these factors have not been studied in families and are unlikely to completely explain the clustering of bowel dysfunction observed in family studies. Furthermore, the familial clustering of IBS does not appear to be explained by psychological traits, based on family studies as well as candidate gene studies of functional variants associated with other psychiatric disorders. To date, over a hundred genetic variants in over 60 genes from various pathways have been studied in a number of candidate gene studies with several positive associations reported. These findings suggest that there may be distinct, as well as shared, molecular underpinnings for IBS and its subtypes. Much new and confirmatory work remains to be performed to elucidate the role of specific genetic variants in IBS development, as well as the specific ways the genes and environment interact to result in IBS susceptibility. PMID:21333900

Novel Therapies in IBS-D Treatment.

PubMed

Nee, Judy; Zakari, Mohammed; Lembo, Anthony J

2015-12-01

Irritable bowel syndrome (IBS) is a common gastrointestinal disease characterized by abdominal pain and change in bowel habits. IBS diarrhea predominant (IBS-D), which is arguably the most common subset of IBS, is also associated with rectal urgency, increased frequency, abdominal bloating, and loose to watery stools. Current treatments for diarrhea include mu-opioid agonists (i.e., loperamide, lomotil) and bile acid sequestrants (i.e., cholestyramine) while treatments for abdominal pain include antispasmodics (i.e., hyoscyamine, dicyclomine) and tricyclic antidepressants (i.e., amitriptyline). There are currently 3 FDA-approved treatments for IBS-D, which have been shown to improve both abdominal pain and diarrhea. Alosetron was initially approved by FDA 2000; however, its use is now limited to women with severe IBS-D symptoms refractory to other treatment. Eluxadoline, a mixed mu-opioid agonist, and rifaximin, a broad spectrum gut specific antibiotic, were both FDA approved in 2015. Eluxadoline has been shown to relieve abdominal pain and stool consistency in appropriate candidates. While large trials already showed the efficacy of rifaximin in treating non-constipated IBS for bloating, stool consistency, and abdominal pain, the recent TARGET 3 trial demonstrates that retreatment is also effective. While these new treatments significantly expand options for patients suffering from IBS-D, there is likely to remain a need for additional safe and effective therapies.

[Therapeutic outcomes in patients with cervical cancer FIGO stage IB1].

PubMed

Kornovski, Y; Ismail, E; Kaneva, M

2012-01-01

To establish overall and disease-free survival (OS and DFS) for patients with FIGO IB1 stage cervical cancer for median period of follow-up of 41 months. Between 11.2002-11.2011 110 women with histologically confirmed cervical cancer IB1 stage were operated on by the author. Surgery was radical hysterectomy class III (Piver) and pelvic lymphonodulectomy (ovariectomy was optionally). 76 patients were submitted to adjuvant RT (TGT- 52 - 54 Gy). The period of follow-up ranges from 2 to 104 monts, median 41 monts. The acturial OS and DFS in patients with cervical cancer IB1 stage were estimated as 90% and 90.9%, respectively. Eleven patients had died for the period of follow-up and in 10 occurred local or distant recurrences. The time to develop recurrences was estimated as 16.81 months. Four patients developed local recurrences and six--distant metastases. Surgical and combined therapy of cervical cancer patients IB1 stage leads to high rate OS and DFS--90% and 90.9%, respectively. The incidence rate of distant metastases (5.5%)--in six patients in this stage makes pelvic lymph node dissection crucial and the presence of LM in gluteal and presacral lymph nodes requires paraaortic lymph node dissection.

Heating and Cooling Rates With an Esophageal Heat Exchange System.

PubMed

Kalasbail, Prathima; Makarova, Natalya; Garrett, Frank; Sessler, Daniel I

2018-04-01

The Esophageal Cooling Device circulates warm or cool water through an esophageal heat exchanger, but warming and cooling efficacy in patients remains unknown. We therefore determined heat exchange rates during warming and cooling. Nineteen patients completed the trial. All had general endotracheal anesthesia for nonthoracic surgery. Intraoperative heat transfer was measured during cooling (exchanger fluid at 7°C) and warming (fluid at 42°C). Each was evaluated for 30 minutes, with the initial condition determined randomly, starting at least 40 minutes after induction of anesthesia. Heat transfer rate was estimated from fluid flow through the esophageal heat exchanger and inflow and outflow temperatures. Core temperature was estimated from a zero-heat-flux thermometer positioned on the forehead. Mean heat transfer rate during warming was 18 (95% confidence interval, 16-20) W, which increased core temperature at a rate of 0.5°C/h ± 0.6°C/h (mean ± standard deviation). During cooling, mean heat transfer rate was -53 (-59 to -48) W, which decreased core temperature at a rate of 0.9°C/h ± 0.9°C/h. Esophageal warming transferred 18 W which is considerably less than the 80 W reported with lower or upper body forced-air covers. However, esophageal warming can be used to supplement surface warming or provide warming in cases not amenable to surface warming. Esophageal cooling transferred more than twice as much heat as warming, consequent to the much larger difference between core and circulating fluid temperature with cooling (29°C) than warming (6°C). Esophageal cooling extracts less heat than endovascular catheters but can be used to supplement catheter-based cooling or possibly replace them in appropriate patients.

Thermal electron heating rate: A derivation

NASA Technical Reports Server (NTRS)

Hoegy, W. R.

1983-01-01

The thermal electron heating rate is an important heat source term in the ionospheric electron energy balance equation, representing heating by photoelectrons or by precipitating higher energy electrons. A formula for the thermal electron heating rate is derived from the kinetic equation using the electron-electron collision operator as given by the unified theory of Kihara and Aono. This collision operator includes collective interactions to produce a finite collision operator with an exact Coulomb logarithm term. The derived heating rate O(e) is the sum of three terms, O(e) = O(p) + S + O(int), which are respectively: (1) primary electron production term giving the heating from newly created electrons that have not yet suffered collisions with the ambient electrons; (2) a heating term evaluated on the energy surface m(e)/2 = E(T) at the transition between Maxwellian and tail electrons at E(T); and (3) the integral term representing heating of Maxwellian electrons by energetic tail electrons at energies ET. Published ionospheric electron temperature studies used only the integral term O(int) with differing lower integration limits. Use of the incomplete heating rate could lead to erroneous conclusions regarding electron heat balance, since O(e) is greater than O(int) by as much as a factor of two.

Adjuvant treatment of stage IB NSCLC: the problem of stage subset heterogeneity.

PubMed

Calhoun, Royce; Jablons, David; Lau, Derick; Gandara, David R

2008-04-30

While 5-year survival rates in patients with stage IB non-small-cell lung cancer (NSCLC) are historically modest (40% to 67%), adjuvant chemotherapy trials including this subgroup have shown little evidence of chemotherapeutic benefit. This article reviews the available data regarding adjuvant chemotherapy following surgically resected stage IB NSCLC, framed within the context of present and future proposed definitions of this diagnosis. The discussion addresses limitations of the current staging system and how this contributes to the mixed results seen with adjuvant treatment. In addition, the authors consider current treatment options for stage IB NSCLC and review planned clinical trials for stage I disease designed to exploit new pharmacogenomic findings.

Psychometric assessment of the IBS-D Daily Symptom Diary and Symptom Event Log.

PubMed

Rosa, Kathleen; Delgado-Herrera, Leticia; Zeiher, Bernie; Banderas, Benjamin; Arbuckle, Rob; Spears, Glen; Hudgens, Stacie

2016-12-01

Diarrhea-predominant irritable bowel syndrome (IBS-D) can considerably impact patients' lives. Patient-reported symptoms are crucial in understanding the diagnosis and progression of IBS-D. This study psychometrically evaluates the newly developed IBS-D Daily Symptom Diary and Symptom Event Log (hereafter, "Event Log") according to US regulatory recommendations. A US-based observational field study was conducted to understand cross-sectional psychometric properties of the IBS-D Daily Symptom Diary and Event Log. Analyses included item descriptive statistics, item-to-item correlations, reliability, and construct validity. The IBS-D Daily Symptom Diary and Event Log had no items with excessive missing data. With the exception of two items ("frequency of gas" and "accidents"), moderate to high inter-item correlations were observed among all items of the IBS-D Daily Symptom Diary and Event Log (day 1 range 0.67-0.90). Item scores demonstrated reliability, with the exception of the "frequency of gas" and "accidents" items of the Diary and "incomplete evacuation" item of the Event Log. The pattern of correlations of the IBS-D Daily Symptom Diary and Event Log item scores with generic and disease-specific measures was as expected, moderate for similar constructs and low for dissimilar constructs, supporting construct validity. Known-groups methods showed statistically significant differences and monotonic trends in each of the IBS-D Daily Symptom Diary item scores among groups defined by patients' IBS-D severity ratings ("none"/"mild," "moderate," or "severe"/"very severe"), supporting construct validity. Initial psychometric results support the reliability and validity of the items of the IBS-D Daily Symptom Diary and Event Log.

Fast wave direct electron heating in advanced inductive and ITER baseline scenario discharges in DIII-D

DOE PAGES

Pinsker, R. I.; Austin, M. E.; Diem, S. J.; ...

2014-02-12

Fast Wave (FW) heating and electron cyclotron heating (ECH) are used in the DIII-D tokamak to study plasmas with low applied torque and dominant electron heating characteristic of burning plasmas. FW heating via direct electron damping has reached the 2.5 MW level in high performance ELMy H-mode plasmas. In Advanced Inductive (AI) plasmas, core FW heating was found to be comparable to that of ECH, consistent with the excellent first-pass absorption of FWs predicted by ray-tracing models at high electron beta. FW heating at the ~2 MW level to ELMy H-mode discharges in the ITER Baseline Scenario (IBS) showed unexpectedlymore » strong absorption of FW power by injected neutral beam (NB) ions, indicated by significant enhancement of the D-D neutron rate, while the intended absorption on core electrons appeared rather weak. As a result, the AI and IBS discharges are compared in an effort to identify the causes of the different response to FWs.« less

Fast wave direct electron heating in advanced inductive and ITER baseline scenario discharges in DIII-D

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

Pinsker, R. I.; Jackson, G. L.; Luce, T. C.

Fast Wave (FW) heating and electron cyclotron heating (ECH) are used in the DIII-D tokamak to study plasmas with low applied torque and dominant electron heating characteristic of burning plasmas. FW heating via direct electron damping has reached the 2.5 MW level in high performance ELMy H-mode plasmas. In Advanced Inductive (AI) plasmas, core FW heating was found to be comparable to that of ECH, consistent with the excellent first-pass absorption of FWs predicted by ray-tracing models at high electron beta. FW heating at the ∼2 MW level to ELMy H-mode discharges in the ITER Baseline Scenario (IBS) showed unexpectedlymore » strong absorption of FW power by injected neutral beam (NB) ions, indicated by significant enhancement of the D-D neutron rate, while the intended absorption on core electrons appeared rather weak. The AI and IBS discharges are compared in an effort to identify the causes of the different response to FWs.« less

Fast wave direct electron heating in advanced inductive and ITER baseline scenario discharges in DIII-D

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

Pinsker, R. I.; Austin, M. E.; Diem, S. J.

Fast Wave (FW) heating and electron cyclotron heating (ECH) are used in the DIII-D tokamak to study plasmas with low applied torque and dominant electron heating characteristic of burning plasmas. FW heating via direct electron damping has reached the 2.5 MW level in high performance ELMy H-mode plasmas. In Advanced Inductive (AI) plasmas, core FW heating was found to be comparable to that of ECH, consistent with the excellent first-pass absorption of FWs predicted by ray-tracing models at high electron beta. FW heating at the ~2 MW level to ELMy H-mode discharges in the ITER Baseline Scenario (IBS) showed unexpectedlymore » strong absorption of FW power by injected neutral beam (NB) ions, indicated by significant enhancement of the D-D neutron rate, while the intended absorption on core electrons appeared rather weak. As a result, the AI and IBS discharges are compared in an effort to identify the causes of the different response to FWs.« less

Stadium IB - IIA cervical cancer patient’s survival rate after receiving definitive radiation and radical operation therapy followed by adjuvant radiation therapy along with analysis of factors affecting the patient’s survival rate

NASA Astrophysics Data System (ADS)

Ruslim, S. K.; Purwoto, G.; Widyahening, I. S.; Ramli, I.

2017-08-01

To evaluate the characteristics and overall survival rates of early stage cervical cancer (FIGO IB-IIA) patients who receive definitive radiation therapy and those who are prescribed adjuvant postoperative radiation and to conduct a factors analysis of the variables that affect the overall survival rates in both groups of therapy. The medical records of 85 patients with cervical cancer FIGO stages IB-IIA who were treated at the Department of Radiotherapy of Cipto Mangunkusumo Hospital were reviewed and analyzed to determine their overall survival and the factors that affected it between a definitive radiation group and an adjuvant postoperative radiation group. There were 25 patients in the definitive radiation and 60 patients in the adjuvant radiation group. The overall survival rates in the adjuvant radiation group at years one, two, and three were 96.7%, 95%, and 93.3%, respectively. Negative lymph node metastasis had an average association with overall survival (p < 0.2). In the definitive radiation group, overall survival at years one, two, and three were 96%, 92%, and 92%, respectively. A hemoglobin (Hb) level >12 g/dl was a factor with an average association with the overall survival (p < 0.2). The differences between both groups of therapy were not statistically significant (92% vs. 93.3%; p = 0.138). This study did not show any statistically significant overall survival for cervical cancer FIGO stage IB-IIA patients who received definitive radiation or adjuvant postoperative radiation. Negative lymph node metastasis had an effect on the overall survival rate in the adjuvant postoperative radiation group, while a preradiation Hb level >12 g/dl tended to affect the overall survival in the definitive radiation group patients.

Does a low FODMAP diet help IBS?

PubMed

2015-08-01

Irritable bowel syndrome (IBS) is a common condition that can have a significant impact on a person's quality of life. The cause of IBS is unknown but several mechanisms have been proposed including visceral hypersensitivity, central sensitisation, abnormal gut motility and altered gut microbiota. IBS is challenging to manage and many patients report insufficient symptomatic relief from treatment. Approximately 60% of patients identify food as a trigger for their symptoms, and there has been interest in exclusion diets for managing IBS. Dietary adaptation is a common self-management strategy for patients with IBS, with many self-diagnosing intolerance to specific foods. This may lead to patients adopting over-restrictive or inappropriate diets. In recent years, a diet low in poorly absorbed short-chain carbohydrates, known collectively as FODMAPs (fermentable oligosaccharides, disaccharides, monosaccharides and polyols), has been advocated for the treatment of IBS. Here, we discuss the background to the FODMAP diet and review the evidence supporting its use for people with IBS. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Towards a better understanding of the evolution of Wolf-Rayet stars and Type Ib/Ic supernova progenitors

NASA Astrophysics Data System (ADS)

Yoon, Sung-Chul

2017-10-01

Hydrogen-deficient Wolf-Rayet (WR) stars are potential candidates of Type Ib/Ic supernova (SN Ib/Ic) progenitors and their evolution is governed by mass-loss. Stellar evolution models with the most popular prescription for WR mass-loss rates given by Nugis & Lamers have difficulties in explaining the luminosity distribution of WR stars of WC and WO types and the SN Ic progenitor properties. Here, we suggest some improvements in the WR mass-loss rate prescription and discuss its implications for the evolution of WR stars and SN Ib/Ic progenitors. Recent studies on Galactic WR stars clearly indicate that the mass-loss rates of WC stars are systematically higher than those of WNE stars for a given luminosity. The luminosity and initial metallicity dependences of WNE mass-loss rates are also significantly different from those of WC stars. These factors have not been adequately considered together in previous stellar evolution models. We also find that an overall increase of WR mass-loss rates by about 60 per cent compared to the empirical values obtained with a clumping factor of 10 is needed to explain the most faint WC/WO stars. This moderate increase with our new WR mass-loss rate prescription results in SN Ib/Ic progenitor models more consistent with observations than those given by the Nugis & Lamers prescription. In particular, our new models predict that the properties of SN Ib and SN Ic progenitors are distinctively different, rather than they form a continuous sequence.

The impact of irritable bowel syndrome on daily functioning: Characterizing and understanding daily consequences of IBS.

PubMed

Ballou, S; Keefer, L

2017-04-01

Despite the well-documented economic and psychosocial burden of irritable bowel syndrome (IBS), few studies have focused on the impact of IBS on daily activities. This study aims to quantitate impairment in daily activities among IBS patients and to evaluate the relationship between impairment, IBS, quality of life, and psychiatric symptoms. A total of 179 participants meeting ROME-III criteria for IBS completed an online research survey evaluating the following variables: (i) the impact of IBS on daily activities, (ii) comorbid psychiatric diagnoses, (iii) symptom severity, (iv) quality of life, and (v) symptom-specific cognitive affective factors related to IBS. This sample reported a high degree of impairment due to IBS, with 76% of the sample reporting some degree of IBS-related impairment in at least five different domains of daily life. Rates of impairment were significantly higher for participants who met criteria for anxiety, depression, and/or panic disorder. This study contributes to existing literature by demonstrating a high level of daily impairment among patients with IBS, particularly those who meet criteria for anxiety, depression, and panic disorder. These findings support the importance of integrated psychosocial and medical care for IBS patients, and highlight the utility of evaluation and intervention for behavioral avoidance/impairment especially among those who exhibit signs or symptoms of psychiatric diagnoses. © 2016 John Wiley & Sons Ltd.

Small intestinal permeability is increased in diarrhoea predominant IBS, while alterations in gastroduodenal permeability in all IBS subtypes are largely attributable to confounders.

PubMed

Mujagic, Z; Ludidi, S; Keszthelyi, D; Hesselink, M A M; Kruimel, J W; Lenaerts, K; Hanssen, N M J; Conchillo, J M; Jonkers, D M A E; Masclee, A A M

2014-08-01

Intestinal permeability has been studied in small groups of IBS patients with contrasting findings. To assess intestinal permeability at different sites of the GI tract in different subtypes of well-characterised IBS patients and healthy controls (HC), and to assess potential confounding factors. IBS patients and HC underwent a multi-sugar test to assess site-specific intestinal permeability. Sucrose excretion and lactulose/rhamnose ratio in 0-5 h urine indicated gastroduodenal and small intestinal permeability, respectively. Sucralose/erythritol ratio in 0-24 h and 5-24 h urine indicated whole gut and colonic permeability, respectively. Linear regression analysis was used to assess the association between IBS groups and intestinal permeability and to adjust for age, sex, BMI, anxiety or depression, smoking, alcohol intake and use of medication. Ninety-one IBS patients, i.e. 37% IBS-D, 23% IBS-C, 33% IBS-M and 7% IBS-U and 94 HC were enrolled. Urinary sucrose excretion was significantly increased in the total IBS group [μmol, median (Q1;Q3): 5.26 (1.82;11.03) vs. 2.44 (0.91;5.85), P < 0.05], as well as in IBS-C and IBS-D vs. HC. However, differences attenuated when adjusting for confounders. The lactulose/rhamnose ratio was increased in IBS-D vs. HC [0.023 (0.013;0.038) vs. 0.014 (0.008;0.025), P < 0.05], which remained significant after adjustment for confounders. No difference was found in 0-24 and 5-24 h sucralose/erythritol ratio between groups. Small intestinal permeability is increased in patients with IBS-D compared to healthy controls, irrespective of confounding factors. Adjustment for confounders is necessary when studying intestinal permeability, especially in a heterogeneous disorder such as IBS. © 2014 John Wiley & Sons Ltd.

Preinduced intestinal HSP70 improves visceral hypersensitivity and abnormal intestinal motility in PI-IBS mouse model.

PubMed

Lan, Cheng; Sun, Xiao-Ning; Zhou, Xu-Chun; Yang, Bo; Huang, Bai-Li; Deng, Tao-Zhi; He, Zhou-Tao; Han, Xiang-Yang

2016-03-01

To investigate the impact of the preinduced intestinal heat shock protein 70 (HSP70) on the visceral hypersensitivity and abnormal intestinal motility in a post-infectious irritable bowel syndrome (PI-IBS) mouse model. Eighty-four female C57BL/6 mice were randomly assigned to four groups: control group (n = 21) and induction + PI-IBS group (n = 21), PI-IBS group (n = 21) and induction group (n = 21). The mice in PI-IBS group were infected in vivo with Trichinella spiralis by oral administration. The visceral hypersensitivity and intestinal motility were evaluated respectively with abdominal withdrawal reflex and colon transportation test. The intestinal HSP70 protein and mRNA level was measured by Western blot and real-time PCR. Meanwhile, the intestinal proinflammatory cytokines IL-10 and TNF-α level was detected by ELISA. Compared with their counterparts in PI-IBS group, the animals in the Induction + PI-IBS group show significantly increased intestinal level of HSP70 and obviously ameliorative clinical figures, including abdominal withdrawal reflex score, intestine transportation time and Bristol scores (P < 0.05). Meanwhile, the intestinal post-inflammatory cytokines remarkably changed, including increased IL-10 level and decreased TNF-α level (P < 0.05). Intestinal HSP70 may play a potential protective role through improving the imbalance between the intestinal post-inflammatory and anti-inflammatory cytokines in PI-IBS. Copyright © 2016 Hainan Medical College. Production and hosting by Elsevier B.V. All rights reserved.

Anxiety and depression comorbidities in irritable bowel syndrome (IBS): a systematic review and meta-analysis.

PubMed

Fond, Guillaume; Loundou, Anderson; Hamdani, Nora; Boukouaci, Wahid; Dargel, Aroldo; Oliveira, José; Roger, Matthieu; Tamouza, Ryad; Leboyer, Marion; Boyer, Laurent

2014-12-01

Irritable bowel syndrome (IBS) has been associated with high prevalence of psychological disorders. However, it remains unclear whether IBS and each of its subtypes (predominant diarrhea IBS-D, constipation IBS-C, mixed IBS-M) are associated with higher anxiety and depressive symptoms levels. This study aimed to determine the associations of IBS and each of its subtypes with anxiety and/or depression. We conducted a systematic review and meta-analysis using five electronic databases (PubMed, PsychINFO, BIOSIS, Science Direct, and Cochrane CENTRAL). We selected case-control studies comparing anxiety and depression levels of patients with IBS to healthy controls, using standardized rating scales. Outcomes were measured as random pooled standardized mean differences (SMD). Ten studies were included in our analysis (885 patients and 1,384 healthy controls). Patients with IBS had significant higher anxiety and depression levels than controls (respectively, SMD = 0.76, 95 % CI 0.47; 0.69, p < 0.01, I2 = 81.7 % and SMD = 0.80, 95 % CI 0.42; 1.19, p < 0.01, I2 = 90.7 %). This significant difference was confirmed for patients with IBS-C and -D subtypes for anxiety, and only in IBS-D patients for depression. However, other IBS subtypes had a statistical trend to be associated with both anxiety and depressive symptomatology, which suggests a lack of power due to the small number of studies included. Patients with IBS had significantly higher levels of anxiety and depression than healthy controls. Anxiety and depression symptomatology should be systematically checked and treated in IBS patients, as psychological factors are important moderators of symptom severity, symptom persistence, decisions to seek treatment, and response to treatment.

Integrated Baseline System (IBS). Version 1.03, System Management Guide

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

Williams, J.R.; Bailey, S.; Bower, J.C.

This IBS System Management Guide explains how to install or upgrade the Integrated Baseline System (IBS) software package. The IBS is an emergency management planning and analysis tool that was developed under the direction of the Federal Emergency Management Agency (FEMA). This guide includes detailed instructions for installing the IBS software package on a Digital Equipment Corporation (DEC) VAX computer from the IBS distribution tapes. The installation instructions include procedures for both first-time installations and upgrades to existing IBS installations. To ensure that the system manager has the background necessary for successful installation of the IBS package, this guide alsomore » includes information on IBS computer requirements, software organization, and the generation of IBS distribution tapes. When special utility programs are used during IBS installation and setups, this guide refers you to the IBS Utilities Guide for specific instructions. This guide also refers you to the IBS Data Management Guide for detailed descriptions of some IBS data files and structures. Any special requirements for installation are not documented here but should be included in a set of installation notes that come with the distribution tapes.« less

Endocannabinoid and cannabinoid-like fatty acid amide levels correlate with pain-related symptoms in patients with IBS-D and IBS-C: a pilot study.

PubMed

Fichna, Jakub; Wood, Jodianne T; Papanastasiou, Malvina; Vadivel, Subramanian K; Oprocha, Piotr; Sałaga, Maciej; Sobczak, Marta; Mokrowiecka, Anna; Cygankiewicz, Adam I; Zakrzewski, Piotr K; Małecka-Panas, Ewa; Krajewska, Wanda M; Kościelniak, Piotr; Makriyannis, Alexandros; Storr, Martin A

2013-01-01

Irritable bowel syndrome (IBS) is a functional gastrointestinal (GI) disorder, associated with alterations of bowel function, abdominal pain and other symptoms related to the GI tract. Recently the endogenous cannabinoid system (ECS) was shown to be involved in the physiological and pathophysiological control of the GI function. The aim of this pilot study was to investigate whether IBS defining symptoms correlate with changes in endocannabinoids or cannabinoid like fatty acid levels in IBS patients. AEA, 2-AG, OEA and PEA plasma levels were determined in diarrhoea-predominant (IBS-D) and constipation-predominant (IBS-C) patients and were compared to healthy subjects, following the establishment of correlations between biolipid contents and disease symptoms. FAAH mRNA levels were evaluated in colonic biopsies from IBS-D and IBS-C patients and matched controls. Patients with IBS-D had higher levels of 2AG and lower levels of OEA and PEA. In contrast, patients with IBS-C had higher levels of OEA. Multivariate analysis found that lower PEA levels are associated with cramping abdominal pain. FAAH mRNA levels were lower in patients with IBS-C. IBS subtypes and their symptoms show distinct alterations of endocannabinoid and endocannabinoid-like fatty acid levels. These changes may partially result from reduced FAAH expression. The here reported changes support the notion that the ECS is involved in the pathophysiology of IBS and the development of IBS symptoms.

TSH elevations as the first laboratory evidence for pseudohypoparathyroidism type Ib (PHP-Ib).

PubMed

Molinaro, Angelo; Tiosano, Dov; Takatani, Rieko; Chrysis, Dionisios; Russell, William; Koscielniak, Nikolas; Kottler, Marie-Laure; Agretti, Patrizia; De Marco, Giuseppina; Ahtiainen, Petteri; Christov, Marta; Mäkitie, Outi; Tonacchera, Massimo; Jüppner, Harald

2015-05-01

Hypocalcemia and hyperphosphatemia because of resistance toward parathyroid hormone (PTH) in the proximal renal tubules are the most prominent abnormalities in patients affected by pseudohypoparathyroidism type Ib (PHP-Ib). In this rare disorder, which is caused by GNAS methylation changes, resistance can occur toward other hormones, such as thyroid-stimulating hormone (TSH), that mediate their actions through G protein-coupled receptors. However, these additional laboratory abnormalities are usually not recognized until PTH-resistant hypocalcemia becomes clinically apparent. We now describe four pediatric patients, first diagnosed with subclinical or overt hypothyroidism between the ages of 0.2 and 15 years, who developed overt PTH-resistance 3 to 20 years later. Although anti-thyroperoxidase (anti-TPO) antibodies provided a plausible explanation for hypothyroidism in one of these patients, this and two other patients revealed broad epigenetic GNAS abnormalities, which included loss of methylation (LOM) at exons AS, XL, and A/B, and gain of methylation at exon NESP55; ie, findings consistent with PHP-Ib. LOM at GNAS exon A/B alone led in the fourth patient to the identification of a maternally inherited 3-kb STX16 deletion, a well-established cause of autosomal dominant PHP-Ib. Although GNAS methylation changes were not detected in additional pediatric and adult patients with subclinical hypothyroidism (23 pediatric and 39 adult cases), hypothyroidism can obviously be the initial finding in PHP-Ib patients. One should therefore consider measuring PTH, along with calcium and phosphate, in patients with unexplained hypothyroidism for extended periods of time to avoid hypocalcemia and associated clinical complications. © 2014 American Society for Bone and Mineral Research.

Pediatric IBS: an overview on pathophysiology, diagnosis and treatment.

PubMed

Chogle, Ashish; Mintjens, Stijn; Saps, Miguel

2014-04-01

Irritable bowel syndrome (IBS) is a common disorder in children and adults. The pathogenesis and pathophysiology of IBS remains incompletely understood. The biopsychosocial model, which conceptualizes chronic pain as a dysregulation of the gut-brain-homeostasis with peripheral and central factors mutually influencing each other, is the most accepted framework to explain IBS. Twin and family aggregation studies suggest a genetic component that does not exclusively explain the higher prevalence of IBS in certain families. Social learning (environmental factors) and maladaptive coping predispose children to develop IBS with greater disability and more frequent medical consultations. Early-life events constitute an additional risk factor for the development of IBS and other functional gastrointestinal disorders (FGIDs). Children with a history of cow's milk protein hypersensitivity or abdominal surgeries have a higher prevalence of IBS and other FGIDs years later. IBS frequently follows an episode of acute gastrointestinal inflammation (infectious or non-infectious). This article discusses the importance, known pathophysiological mechanisms, clinical approach, and evidence-based therapeutic options for the management of IBS in children and adolescents. Copyright 2014, SLACK Incorporated.

IBS suppression lattice in RHIC: theory and experimental verification

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

Fedotov,A.V.; Bai, M.; Bruno, D.

Intra-beam scattering (IBS) is the limiting factor of the luminosity lifetime for Relativistic Heavy Ion Collider (RHIC) operation with heavy ions. Over the last few years the process of IBS was carefully studied in RHIC with dedicated IBS measurements and their comparison with the theoretical models. A new lattice was recently designed and implemented in RHIC to suppress transverse IBS growth, which lowered the average arc dispersion by about 20% [1]. This lattice became operational during RHIC Run-8. We review the IBS suppression mechanism, IBS measurements before and after the lattice change, and comparisons with predictions.

Paternal uniparental isodisomy of the entire chromosome 20 as a molecular cause of pseudohypoparathyroidism type Ib (PHP-Ib).

PubMed

Bastepe, Murat; Altug-Teber, Ozge; Agarwal, Chhavi; Oberfield, Sharon E; Bonin, Michael; Jüppner, Harald

2011-03-01

Pseudohypoparathyoridism type Ib (PHP-Ib) typically defines the presence of end-organ resistance to parathyroid hormone in the absence of Albright's hereditary osteodystrophy. Patients affected by this disorder present with imprinting defects in the complex GNAS locus. Microdeletions within STX16 or GNAS have been identified in familial cases with PHP-Ib, but the molecular cause of the GNAS imprinting defects in sporadic PHP-Ib cases remains poorly defined. We now report a case with sporadic PHP-Ib for whom a SNPlex analysis revealed loss of the maternal GNAS allele. Further analysis of the entire genome with a 100K SNP chip identified a paternal uniparental isodisomy affecting the entire chromosome 20 without evidence for another chromosomal abnormality. Our findings explain the observed GNAS methylation changes and the patient's hormone resistance, and furthermore suggest that chromosome 20 harbors, besides GNAS, no additional imprinted region that contributes to the clinical and laboratory phenotype. Copyright © 2010 Elsevier Inc. All rights reserved.

TSH elevations as the first laboratory evidence for pseudohypoparathyroidism type Ib (PHP-Ib)†

PubMed Central

Molinaro, Angelo; Tiosano, Dov; Takatani, Rieko; Chrysis, Dionisios; Russell, William; Koscielniak, Nikolas; Kottler, Marie-Laure; Agretti, Patrizia; De Marco, Giuseppina; Ahtiainen, Petteri; Christov, Marta; Mäkitie, Outi; Tonacchera, Massimo; Jüppner, Harald

2014-01-01

Hypocalcemia and hyperphosphatemia because of resistance towards parathyroid hormone (PTH) in the proximal renal tubules are the most prominent abnormalities in patients affected by pseudohypoparathyroidism type Ib (PHP-Ib). In this rare disorder that is caused by GNAS methylation changes, resistance can occur towards other hormones, such as thyroid-stimulating hormone (TSH), that mediate their actions through G protein-coupled receptors. However, these additional laboratory abnormalities are usually not recognized until PTH-resistant hypocalcemia becomes clinically apparent. We now describe four pediatric patients, first diagnosed with subclinical or overt hypothyroidism between the ages of 0.2 and 15 years, who developed overt PTH-resistance 3-20 years later. Although anti-TPO antibodies provided a plausible explanation for hypothyroidism in one of these patients, this and two other patients revealed broad epigenetic GNAS abnormalities, which included loss of methylation (LOM) at exons AS, XL and A/B, and gain of methylation at exon NESP55, i.e. findings consistent with PHP-Ib. LOM at GNAS exon A/B alone led in the fourth patient to the identification of a maternally inherited 3-kb STX16 deletion, a well-established cause of autosomal dominant PHP-Ib. Although GNAS methylation changes were not detected in additional pediatric and adult patients with subclinical hypothyroidism (23 pediatric and 39 adult cases), hypothyroidism can obviously be the initial finding in PHP-Ib patients. One should therefore consider measuring PTH, along with calcium and phosphate, in patients with unexplained hypothyroidism for extended periods of time to avoid hypocalcemia and associated clinical complications. PMID:25403028

Lessons Learnt from Post-Infectious IBS

PubMed Central

Sarna, Sushil K.

2011-01-01

The development of IBS symptoms – altered bowel function and abdominal cramping in a subset of adult subjects exposed to severe enteric infections opened up an unprecedented opportunity to understand the etiology of this poorly understood disorder. Perhaps, for the reasons that these symptoms follow a severe enteric infection, and mucosal biopsy tissues are readily available, the focus of most studies thus far has been to show that mild/low-grade mucosal inflammation persisting after the initial infection has subsided causes the IBS symptoms. Parallel studies in non-infectious IBS patients, who did not have prior enteritis, showed similar mild mucosal inflammation. Together, these studies examined the mucosal infiltration of specific immune cells, increase of select inflammatory mediators, mast cell and enterochromaffin cell hyperplasia, and epithelial permeability. In spite of the fact that the data on these topics were not consistent among different studies and clinical trials with prednisone, fluoxetine, and ketotifen failed to provide relief of IBS symptoms, the predominant conclusions were that mild mucosal inflammation is the cause of IBS symptoms. However, the circular smooth muscle cells, and myenteric neurons are the primary regulators of gut motility function, while primary afferent neurons and CNS play essential roles in induction of visceral hypersensitivity – no explanation was provided as to how mild mucosal inflammation causes dysfunction in cells far removed. Accumulating evidence shows that mild mucosal inflammation in IBS patients is in physiological range. It has little deleterious effects on cells within its own environment and therefore it is unlikely to affect cells in the muscularis externa. This review discusses the disconnect between the focus on mild/low-grade mucosal inflammation and the potential mechanisms and molecular dysfunctions in smooth muscle cells, myenteric neurons, and primary afferent neurons that may underlie IBS

An Evidence-Based Look at Misconceptions in the Treatment of Patients with IBS-D

PubMed Central

Lacy, Brian E.; Chey, William D.; Chang, Lin

2013-01-01

Irritable bowel syndrome (IBS) is the most common functional gastrointestinal disorder and affects up to 12% to 15% of adults in the United States, with a higher prevalence among women and those younger than 50 years. IBS adversely impacts quality of life and medical expenditures, with significant costs arising from healthcare visits and reduced workplace productivity. Recent studies have shown that the adverse effects of IBS are so significant that many patients are willing to accept risks of adverse events from effective treatment to gain symptom relief. Alosetron is a 5-HT3 receptor antagonist approved by the US Food and Drug Administration (FDA) for women with severe diarrhea-predominant IBS that has not responded to traditional therapies. Alosetron yields overall improvements in IBS symptoms in 51% of patients vs 36% treated with placebo, with efficacy continuing undiminished over the course of a 48-week randomized, controlled trial. In real-world clinical practice, patients receiving alosetron had significant improvements in multiple IBS-related clinical parameters, including the new FDA IBS-diarrhea composite endpoint, lower gastrointestinal symptoms, fecal incontinence, and quality of life. Ischemic colitis and complications of constipation have been rare in occurrence. After nearly a decade of alosetron use under the risk management plan, adjudication of ischemic colitis and complications of constipation cases indicate that their incidence rates have remained low and stable. PMID:24872792

Increased colonic bile acid exposure: a relevant factor for symptoms and treatment in IBS.

PubMed

Bajor, Antal; Törnblom, Hans; Rudling, Mats; Ung, Kjell-Arne; Simrén, Magnus

2015-01-01

Bile acids may play a role in the pathogenesis of IBS. We investigated the potential effects of bile acids entering the colon and its role in the symptom pattern in IBS. We measured 75Se-labelled homocholic acid-taurine (75SeHCAT) retention, and serum levels of 7α-hydroxy-4-cholesten-3-one (C4) and fibroblast growth factor (FGF) 19 in patients with IBS (n=141) and control subjects (75SeHCAT n=29; C4 and FGF19 n=435). In patients with IBS stool frequency and form, as well as GI symptom severity were registered, and in a proportion of patients colonic transit time and rectal sensitivity were measured (n=66). An 8-week open-label treatment with colestipol was offered to patients with 75SeHCAT <20%, and the effect of treatment was evaluated with IBS severity scoring system and adequate relief of IBS symptoms. Compared with controls, patients with IBS had lower 75SeHCAT values (p=0.005), higher C4c levels (C4 corrected for cholesterol) (p<0.001), but similar FGF19 levels. Abnormal 75SeHCAT retention (<10%) was seen in 18% of patients, whereas 23% had elevated C4c levels. Patients with IBS with 75SeHCAT retention <10% had more frequent stools, accelerated colonic transit time, rectal hyposensitivity, a higher body mass index, higher C4c and lower FGF19 levels. Colestipol treatment improved IBS symptoms (IBS severity scoring system 220±109 vs. 277±106; p<0.01), and 15/27 patients fulfilled criteria for treatment response (adequate relief ≥50% of weeks 5-8). Increased colonic bile acid exposure influences bowel habit and colonic transit time in patients with IBS. A high response rate to open label treatment with colestipol supports this, but placebo-controlled studies are warranted. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

IBS Patients Show Frequent Fluctuations between Loose/Watery and Hard/Lumpy Stools: Implications for Treatment

PubMed Central

Palsson, Olafur S.; Baggish, Jeffrey S.; Turner, Marsha J.; Whitehead, William E.

2013-01-01

Aims To determine how variable stool consistency is in patients with irritable bowel (IBS) and assess the relationship between stool consistency and gastrointestinal symptoms. Methods Individuals with a physician diagnosis of IBS were recruited by advertisement. Enrollment questionnaires included the Rome III Diagnostic Questionnaire and IBS Symptom Severity Scale. Then 185 patients meeting Rome criteria for IBS rated the consistency (using the Bristol Stool Scale) of each bowel movement (BM) for 90 days and whether the BM was accompanied by pain, urgency, or soiling. Each night they transferred BM ratings from a paper diary to an internet form and also reported the average daily intensity of abdominal pain, bloating, bowel habit dissatisfaction, and life interference of bowel symptoms. Only the longest sequence of consecutive days of diary data was used in analysis (average of 73 days). Results Patients were 89% female with average age 36.6 years. 78% had both loose/watery and hard/lumpy stools; the average was 3 fluctuations between these extremes per month. The proportion of loose/watery stools correlated r=.78 between the first and second months and the proportion of hard/lumpy stools correlated r=.85 between months. Loose/watery stools were associated with more BM-related pain, urgency, and soiling than hard/lumpy or normal stools; however, IBS-C patients had significantly more BM-unrelated abdominal pain, bloating, dissatisfaction with bowel habits, and life interference than IBS-D. Questionnaires overestimated the frequency of abnormal stool consistency and gastrointestinal symptoms compared to diaries. Conclusions Stool consistency varies greatly within individuals. However, stool patterns are stable within an individual from month to month. The paradoxical findings of greater symptom severity after individual loose/watery BMs vs. greater overall symptom severity in IBS-C implies different physiological mechanisms for symptoms in constipation compared to

The IB Diploma and UK University Degree Qualifications

ERIC Educational Resources Information Center

Frank-Gemmill, Gerda

2013-01-01

In recent years the International Baccalaureate (IB) Diploma has become widely accepted as a university-entry qualification in the UK, but there has been little quantitative research into the achievements of IB students at degree level. This study investigates IB students from one selective independent school who entered UK universities between…

Implications of Pharmacogenomics to the Management of IBS.

PubMed

Camilleri, Michael

2018-04-27

The objectives are to review the role of pharmacogenomics in drug metabolism of medications typically used in patients with irritable bowel syndrome (IBS) focusing predominantly on cytochrome P450 metabolism. Other aims are to provide examples of genetic variation of receptors or intermediary pathways that are targets for IBS drugs and to critically appraise the situations where precision medicine is impacting health in IBS. Pharmacogenomics impacts both pharmacokinetics and pharmacodynamics. Although large clinical trials have not incorporated testing for genetic variations that could impact the efficacy of medications in IBS, there are therapeutic advantages to inclusion of pharmacogenomics testing for individual patients, as has been demonstrated particularly in the treatment with central neuromodulators in psychiatry practice. Clinical practice in IBS is moving in the same direction with the aid of commercially available tests focused on drug metabolism. Specific mechanisms leading to pathophysiology of IBS are still poorly characterized, relative to diseases such as cancer and inflammatory bowel disease, and, therefore, pharmacogenomics related to drug pharmacodynamics is still in its infancy and requires extensive future research. With increased attention to pharmacogenomics affecting drug metabolism, it is anticipated that pharmacogenomics will impact care of IBS. Copyright © 2018 AGA Institute. Published by Elsevier Inc. All rights reserved.

Non-absorbed Antibiotics for IBS

DTIC Science & Technology

2012-03-16

absorbed antibiotic rifaximin for nonconstipated irritable bowel syndrome (IBS). This effort adds to the body of literature from other, smaller studies that...have demonstrated clinical efficacy for IBS with rifaximin . Non-absorbed antibiotics have been endorsed by the American College of Gastroenterology... rifaximin 400 mg three times daily for 10 days or placebo. During the initial 2 weeks of therapy and the subsequent 10 weeks of follow-up rifaximin

Advances in IBS 2016: A Review of Current and Emerging Data.

PubMed

Schoenfeld, Philip S

2016-08-01

Irritable bowel syndrome (IBS) is characterized by chronic intermittent abdominal pain and associated diarrhea (IBS-D), constipation (IBS-C), or both. IBS can significantly impact patient function and quality of life. The diagnosis of IBS is based on the presence of characteristic symptoms, the exclusion of concerning features, and selected tests to exclude organic diseases that can mimic IBS. The pathophysiology of IBS remains incompletely understood, and new contributing factors have been identified over the past decade. Altered gut immune activation, intestinal permeability, and the intestinal and colonic microbiome may be important factors. Poorly absorbed carbohydrates have been implicated in triggering IBS symptoms. Increasing evidence supports the benefit of a diet low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs). Although there are several randomized controlled trials of probiotics in IBS, they are typically poorly designed and have not consistently demonstrated efficacy. Until recently, there were few effective treatments for IBS-D. Data from recent clinical trials support the use of rifaximin, eluxadoline, and peppermint oil. Options for the treatment of IBS-C include lubiprostone and linaclotide.

Advances in IBS 2016: A Review of Current and Emerging Data

PubMed Central

Schoenfeld, Philip S.

2016-01-01

Irritable bowel syndrome (IBS) is characterized by chronic intermittent abdominal pain and associated diarrhea (IBS-D), constipation (IBS-C), or both. IBS can significantly impact patient function and quality of life. The diagnosis of IBS is based on the presence of characteristic symptoms, the exclusion of concerning features, and selected tests to exclude organic diseases that can mimic IBS. The pathophysiology of IBS remains incompletely understood, and new contributing factors have been identified over the past decade. Altered gut immune activation, intestinal permeability, and the intestinal and colonic microbiome may be important factors. Poorly absorbed carbohydrates have been implicated in triggering IBS symptoms. Increasing evidence supports the benefit of a diet low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs). Although there are several randomized controlled trials of probiotics in IBS, they are typically poorly designed and have not consistently demonstrated efficacy. Until recently, there were few effective treatments for IBS-D. Data from recent clinical trials support the use of rifaximin, eluxadoline, and peppermint oil. Options for the treatment of IBS-C include lubiprostone and linaclotide. PMID:28070176

Diagnosis of IBS: symptoms, symptom-based criteria, biomarkers or 'psychomarkers'?

PubMed

Sood, Ruchit; Law, Graham R; Ford, Alexander C

2014-11-01

IBS is estimated to have a prevalence of up to 20% in Western populations and results in substantial costs to health-care services worldwide, estimated to be US$1 billion per year in the USA. IBS remains difficult to diagnose due to its multifactorial aetiology, heterogeneous nature and overlap of symptoms with organic pathologies, such as coeliac disease and IBD. As a result, IBS often continues to be a diagnosis of exclusion, resulting in unnecessary investigations. Available methods for the diagnosis of IBS-including the current gold standard, the Rome III criteria-perform only moderately well. Visceral hypersensitivity and altered pain perception do not discriminate between IBS and other functional gastrointestinal diseases or health with any great accuracy. Attention has now turned to developing novel biomarkers and using psychological markers (so-called psychomarkers) to aid the diagnosis of IBS. This Review describes how useful symptoms, symptom-based criteria, biomarkers and psychomarkers, and indeed combinations of all these approaches, are in the diagnosis of IBS. Future directions in diagnosing IBS could include combining demographic data, gastrointestinal symptoms, biomarkers and psychomarkers using statistical methods. Latent class analysis to distinguish between IBS and non-IBS symptom profiles might also represent a promising avenue for future research.

Development and pilot testing of an integrated, web-based self-management program for irritable bowel syndrome (IBS).

PubMed

Dorn, S D; Palsson, O S; Woldeghebriel, M; Fowler, B; McCoy, R; Weinberger, M; Drossman, D A

2015-01-01

Although essential, many medical practices are unable to adequately support irritable bowel syndrome (IBS) patient self-management. Web-based programs can help overcome these barriers. We developed, assessed, and refined an integrated IBS self-management program (IBS Self-care). We then conducted a 12-week pilot test to assess program utilization, evaluate its association with patients' self-efficacy and quality of life, and collect qualitative feedback to improve the program. 40 subjects with generally mild IBS were recruited via the Internet to participate in a 12-week pilot study. Subjects found the website easy to use (93%) and personally relevant (95%), and 90% would recommend it to a friend. Self-rated IBS knowledge increased from an average of 47.1 on a 100-point VAS scale (SD 22.1) at baseline to 77.4 (SD: 12.4) at week 12 (p < 0.0001). There were no significant changes in patient self-efficacy (Patient Activation Measure) or quality of life (IBS -Quality of Life Scale). The IBS Self-Care program was well received by users who after 12 weeks reported improved knowledge about IBS, but no significant changes in self-efficacy or quality of life. If applied to the right population, this low cost solution can overcome some of the deficiencies of medical care and empower individuals to better manage their own IBS. © 2014 John Wiley & Sons Ltd.

Effect of linaclotide in irritable bowel syndrome with constipation (IBS-C): a systematic review and meta-analysis.

PubMed

Atluri, D K; Chandar, A K; Bharucha, A E; Falck-Ytter, Y

2014-04-01

Treatment options for constipation-predominant irritable bowel syndrome (IBS-C) are limited. While linaclotide improved IBS-C symptoms in randomized controlled trials (RCTs), results vary among studies and the magnitude of benefit is unclear. Two investigators independently extracted data on study participants, methods and outcomes (i.e., symptoms, quality of life, and adverse events) from eligible articles i.e., RCTs comparing linaclotide with placebo in adult patients with IBS-C with a follow-up of 12 weeks or longer. The grading of recommendations assessment, development and evaluation (GRADE) methodology was used to rate the quality of evidence. Of 182 identified citations, three RCTs enrolling 1773 patients met the inclusion criteria. Compared with placebo, fewer patients on linaclotide failed to achieve responses i.e., FDA endpoint (1604 patients, risk ratio [RR] = 0.80; 95%CI 0.76-0.85), adequate IBS symptom relief (1773 patients, RR = 0.73; 95%CI 0.65-0.82), and clinically meaningful improvement in IBS-QOL (1659 patients, RR = 0.78; 95%CI 0.72-0.86). The incidence of diarrhea leading to discontinuation of treatment was higher for linaclotide (1773 patients, RR = 14.75; 95%CI 4.04-53.81). The quality of evidence was rated as moderate for FDA endpoint and adequate relief response, high for diarrhea, and low for IBS-QOL. Generalizability may be limited by the study population (i.e., predominantly white female patients), lack of data regarding prior therapy, and availability of few RCTs. The number of patients is insufficient to identify rare adverse events. Linaclotide is moderately effective in improving symptoms of IBS-C with diarrhea being the major side effect. Further studies are needed to evaluate the long-term efficacy and safety of linaclotide for IBS-C. © 2013 John Wiley & Sons Ltd.

Eluxadoline Efficacy in IBS-D Patients Who Report Prior Loperamide Use.

PubMed

Lacy, Brian E; Chey, William D; Cash, Brooks D; Lembo, Anthony J; Dove, Leonard S; Covington, Paul S

2017-06-01

Irritable bowel syndrome with diarrhea (IBS-D) is often managed with over-the-counter therapies such as loperamide, though with limited success. This analysis evaluated the efficacy of eluxadoline in patients previously treated with loperamide in two phase 3 studies. Adults with IBS-D (Rome III criteria) were enrolled and randomized to placebo or eluxadoline (75 or 100 mg) twice daily for 26 (IBS-3002) or 52 (IBS-3001) weeks. Patients reported loperamide use over the previous year and recorded their rescue loperamide use during the studies. The primary efficacy end point was the proportion of patients with a composite response of simultaneous improvement in abdominal pain and reduction in diarrhea. A total of 2,428 patients were enrolled; 36.0% reported prior loperamide use, of whom 61.8% reported prior inadequate IBS-D symptom control with loperamide. Among patients with prior loperamide use, a greater proportion treated with eluxadoline (75 and 100 mg) were composite responders vs. those treated with placebo with inadequate prior symptom control, over weeks 1-12 (26.3% (P=0.001) and 27.0% (P<0.001) vs. 12.7%, respectively); similar results were observed over weeks 1-26. When daily rescue loperamide use was imputed as a nonresponse day, the composite responder rate was still higher in patients receiving eluxadoline (75 and 100 mg) vs. placebo over weeks 1-12 (P<0.001) and weeks 1-26 (P<0.001). Adverse events included nausea and abdominal pain. Eluxadoline effectively and safely treats IBS-D symptoms of abdominal pain and diarrhea in patients who self-report either adequate or inadequate control of their symptoms with prior loperamide treatment, with comparable efficacy and safety irrespective of the use of loperamide as a rescue medication during eluxadoline treatment.

Heat release rate of wood-plastic composites

Treesearch

N. M. Stark; R. H. White; C. M. Clemons

1997-01-01

Wood-plastic composites are becoming more important as a material that fulfills recycling needs. In this study, fire performance tests were conducted on several compositions of wood and plastic materials using the Ohio State University rate of heat release apparatus. Test results included five-minute average heat release rate in kW/m2 (HRR avg) and maximum heat release...

A mechanistic multicentre, parallel group, randomised placebo-controlled trial of mesalazine for the treatment of IBS with diarrhoea (IBS-D).

PubMed

Lam, Ching; Tan, Wei; Leighton, Matthew; Hastings, Margaret; Lingaya, Melanie; Falcone, Yirga; Zhou, Xiaoying; Xu, Luting; Whorwell, Peter; Walls, Andrew F; Zaitoun, Abed; Montgomery, Alan; Spiller, Robin

2016-01-01

Immune activation has been reported in the mucosa of IBS patients with diarrhoea (IBS-D), and some small studies have suggested that mesalazine may reduce symptoms. We performed a double-blind, randomised placebo-controlled trial of 2 g mesalazine twice daily versus placebo for 3 months in patients with Rome III criteria IBS-D. Primary outcome was daily average stool frequency during weeks 11-12; secondary outcomes were abdominal pain, stool consistency, urgency and satisfactory relief of IBS symptoms. Participants were randomised after a 2-week baseline stool diary. All participants completed a 12-week stool diary and at the end of each week recorded the presence of 'satisfactory relief of IBS symptoms'. 136 patients with IBS-D (82 women, 54 men) were randomised, 10 patients withdrew from each group. Analysis by intention to treat showed the daily average stool frequency during weeks 11 and 12 were mean (SD), 2.8 (1.2) in mesalazine and 2.7 (1.9) in the placebo group with no significant group difference, (95% CI) 0.1 (-0.33 to 0.53), p=0.66. Mesalazine did not improve abdominal pain, stool consistency nor percentage with satisfactory relief compared with placebo during the last two-weeks follow-up. This study does not support any clinically meaningful benefit or harm of mesalazine compared with placebo in unselected patients with IBS-D. More precise subtyping based on underlying disease mechanisms is needed to allow more effective targeting of treatment in IBS. NCT01316718. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Intestinal Microbiota And Diet in IBS: Causes, Consequences, or Epiphenomena?

PubMed Central

Rajilić-Stojanović, Mirjana; Jonkers, Daisy M; Salonen, Anne; Hanevik, Kurt; Raes, Jeroen; Jalanka, Jonna; de Vos, Willem M; Manichanh, Chaysavanh; Golic, Natasa; Enck, Paul; Philippou, Elena; Iraqi, Fuad A; Clarke, Gerard; Spiller, Robin C; Penders, John

2015-01-01

Irritable bowel syndrome (IBS) is a heterogeneous functional disorder with a multifactorial etiology that involves the interplay of both host and environmental factors. Among environmental factors relevant for IBS etiology, the diet stands out given that the majority of IBS patients report their symptoms to be triggered by meals or specific foods. The diet provides substrates for microbial fermentation, and, as the composition of the intestinal microbiota is disturbed in IBS patients, the link between diet, microbiota composition, and microbial fermentation products might have an essential role in IBS etiology. In this review, we summarize current evidence regarding the impact of diet and the intestinal microbiota on IBS symptoms, as well as the reported interactions between diet and the microbiota composition. On the basis of the existing data, we suggest pathways (mechanisms) by which diet components, via the microbial fermentation, could trigger IBS symptoms. Finally, this review provides recommendations for future studies that would enable elucidation of the role of diet and microbiota and how these factors may be (inter)related in the pathophysiology of IBS. PMID:25623659

Intestinal microbiota and diet in IBS: causes, consequences, or epiphenomena?

PubMed

Rajilić-Stojanović, Mirjana; Jonkers, Daisy M; Salonen, Anne; Hanevik, Kurt; Raes, Jeroen; Jalanka, Jonna; de Vos, Willem M; Manichanh, Chaysavanh; Golic, Natasa; Enck, Paul; Philippou, Elena; Iraqi, Fuad A; Clarke, Gerard; Spiller, Robin C; Penders, John

2015-02-01

Irritable bowel syndrome (IBS) is a heterogeneous functional disorder with a multifactorial etiology that involves the interplay of both host and environmental factors. Among environmental factors relevant for IBS etiology, the diet stands out given that the majority of IBS patients report their symptoms to be triggered by meals or specific foods. The diet provides substrates for microbial fermentation, and, as the composition of the intestinal microbiota is disturbed in IBS patients, the link between diet, microbiota composition, and microbial fermentation products might have an essential role in IBS etiology. In this review, we summarize current evidence regarding the impact of diet and the intestinal microbiota on IBS symptoms, as well as the reported interactions between diet and the microbiota composition. On the basis of the existing data, we suggest pathways (mechanisms) by which diet components, via the microbial fermentation, could trigger IBS symptoms. Finally, this review provides recommendations for future studies that would enable elucidation of the role of diet and microbiota and how these factors may be (inter)related in the pathophysiology of IBS.

[Full Sibling Identification by IBS Scoring Method and Establishment of the Query Table of Its Critical Value].

PubMed

Li, R; Li, C T; Zhao, S M; Li, H X; Li, L; Wu, R G; Zhang, C C; Sun, H Y

2017-04-01

To establish a query table of IBS critical value and identification power for the detection systems with different numbers of STR loci under different false judgment standards. Samples of 267 pairs of full siblings and 360 pairs of unrelated individuals were collected and 19 autosomal STR loci were genotyped by Golden e ye™ 20A system. The full siblings were determined using IBS scoring method according to the 'Regulation for biological full sibling testing'. The critical values and identification power for the detection systems with different numbers of STR loci under different false judgment standards were calculated by theoretical methods. According to the formal IBS scoring criteria, the identification power of full siblings and unrelated individuals was 0.764 0 and the rate of false judgment was 0. The results of theoretical calculation were consistent with that of sample observation. The query table of IBS critical value for identification of full sibling detection systems with different numbers of STR loci was successfully established. The IBS scoring method defined by the regulation has high detection efficiency and low false judgment rate, which provides a relatively conservative result. The query table of IBS critical value for identification of full sibling detection systems with different numbers of STR loci provides an important reference data for the result judgment of full sibling testing and owns a considerable practical value. Copyright© by the Editorial Department of Journal of Forensic Medicine

Experience with IBS-suppression lattice in RHIC

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

Litvinenko,V.N.; Luo, Y.; Ptitsyn, V.

An intra-beam scattering (IBS) is the limiting factor of the luminosity lifetime for RHIC operating with heavy ions. In order to suppress the IBS we designed and implemented new lattice with higher betatron tunes. This lattice had been developed during last three years and had been used for gold ions in yellow ring of the RHIC during d-Au part of the RHIC Run-8. The use of this lattice allowed both significant increases in the luminosity lifetime and the luminosity levels via reduction of beta-stars in the IPS. In this paper we report on the development, the tests and the performancemore » of IBS-suppression lattice in RHIC, including the resulting increases in the peak and the average luminosity. We also report on our plans for future steps with the IBS suppression.« less

Platelet Glycoprotein Ib-IX and Malignancy

DTIC Science & Technology

2010-09-01

provide a unique microenvironment supporting the accumulation of more platelets and the elaboration of a fibrin - rich network produced by coagulation...process and can initiate the formation of a platelet - rich thrombus by tethering the platelet to a thrombogenic surface. Several ligands binding to GP Ib... Platelet Glycoprotein Ib-IX and Malignancy PRINCIPAL INVESTIGATOR: Jerry Ware, Ph.D

Widening Participation to an IB Education

ERIC Educational Resources Information Center

Finkel, Ed

2012-01-01

The global economy demands globally educated workers and citizens. About 1,300 schools in the United States--and a total of about 3,200 in 141 countries worldwide--have turned to the International Baccalaureate (IB) curriculum as their ticket to educating students who are worldly-wise. But only 25 or 30 percent of students in IB World Schools are…

Improved platelet survival after cold storage by prevention of glycoprotein Ibα clustering in lipid rafts

PubMed Central

Gitz, Eelo; Koekman, Cornelis A; van den Heuvel, Dave J.; Deckmyn, Hans; Akkerman, Jan W.; Gerritsen, Hans C.; Urbanus, Rolf T.

2012-01-01

Background Storing platelets for transfusion at room temperature increases the risk of microbial infection and decreases platelet functionality, leading to out-date discard rates of up to 20%. Cold storage may be a better alternative, but this treatment leads to rapid platelet clearance after transfusion, initiated by changes in glycoprotein Ibα, the receptor for von Willebrand factor. Design and Methods: We examined the change in glycoprotein Ibα distribution using Förster resonance energy transfer by time-gated fluorescence lifetime imaging microscopy. Results Cold storage induced deglycosylation of glycoprotein Ibα ectodomain, exposing N-acetyl-Dglucosamine residues, which sequestered with GM1 gangliosides in lipid rafts. Raft-associated glycoprotein Ibα formed clusters upon binding of 14-3-3ζ adaptor proteins to its cytoplasmic tail, a process accompanied by mitochondrial injury and phosphatidyl serine exposure. Cold storage left glycoprotein Ibα surface expression unchanged and although glycoprotein V decreased, the fall did not affect glycoprotein Ibα clustering. Prevention of glycoprotein Ibα clustering by blockade of deglycosylation and 14-3-3ζ translocation increased the survival of cold-stored platelets to above the levels of platelets stored at room temperature without compromising hemostatic functions. Conclusions We conclude that glycoprotein Ibα translocates to lipid rafts upon cold-induced deglycosylation and forms clusters by associating with 14-3-3ζ. Interference with these steps provides a means to enable cold storage of platelet concentrates in the near future. PMID:22733027

More negative self-esteem and inferior coping strategies among patients diagnosed with IBS compared with patients without IBS--a case-control study in primary care.

PubMed

Grodzinsky, Ewa; Walter, Susanna; Viktorsson, Lisa; Carlsson, Ann-Kristin; Jones, Michael P; Faresjö, Åshild

2015-01-28

Irritable Bowel Syndrome (IBS) is a chronic, relapsing gastrointestinal disorder, that affects approximately 10% of the general population and the majority are diagnosed in primary care. IBS has been reported to be associated with altered psychological and cognitive functioning such as mood disturbances, somatization, catastrophizing or altered visceral interoception by negative emotions and stress. The aim was to investigate the psychosocial constructs of self-esteem and sense of coherence among IBS patients compared to non-IBS patients in primary care. A case-control study in primary care setting among IBS patients meeting the ROME III criteria (n = 140) compared to controls i.e. non-IBS patients (n = 213) without any present or previous gastrointestinal complaints. The data were collected through self-reported questionnaires of psychosocial factors. IBS-patients reported significantly more negative self-esteem (p < 0.001), lower scores for positive self-esteem (p < 0.001), and lower sense of coherence (p < 0.001) than the controls. The IBS-cases were also less likely to report 'good' health status (p < 0.001) and less likely to report a positive belief in the future (p < 0.001). After controlling for relevant confounding factors in multiple regressions, the elevation in negative self-esteem among IBS patients remained statistically significant (p = 0.02), as did the lower scores for sense of coherence among IBS cases (p = 0.04). The more frequently reported negative self-esteem and inferior coping strategies among IBS patients found in this study suggest the possibility that psychological therapies might be helpful for these patients. However these data do not indicate the causal direction of the observed associations. More research is therefore warranted to determine whether these psychosocial constructs are more frequent in IBS patients.

Program documentation: Surface heating rate of thin skin models (THNSKN)

NASA Technical Reports Server (NTRS)

Mcbryde, J. D.

1975-01-01

Program THNSKN computes the mean heating rate at a maximum of 100 locations on the surface of thin skin transient heating rate models. Output is printed in tabular form and consists of time history tabulation of temperatures, average temperatures, heat loss without conduction correction, mean heating rate, least squares heating rate, and the percent standard error of the least squares heating rates. The input tape used is produced by the program EHTS03.

Total costs of IBS: employer and managed care perspective.

PubMed

Cash, Brooks; Sullivan, Sean; Barghout, Victoria

2005-04-01

Irritable bowel syndrome (IBS) is a common gastrointestinal motility disorder that typically affects persons of working age and is costly to employers. The financial burden attributable to the direct (use of healthcare resources) and indirect (missed days from work [absenteeism] and loss of productivity while at work [presenteeism]) costs of IBS is similar to that of other common long-term medical disorders, such as asthma, migraine, hypertension, and congestive heart failure. The symptoms of IBS are significantly bothersome and place a substantial burden on the personal and working lives of patients. As with other long-term medical conditions that have a significant impact on productivity, directed efforts by employers can address IBS in the workplace and thereby potentially decrease its impact. In this article, the symptoms of IBS and its impact on patients and on society as a whole are discussed; options are outlined by which employers can help reduce the total costs of IBS, including lost productivity (both absenteeism and presenteeism), in the workplace.

Burning rate of solid wood measured in a heat release rate calorimeter

Treesearch

H. C. Tran; R. H. White

1992-01-01

Burning rate is a key factor in modeling fire growth and fire endurance of wood structures. This study investigated the burning rate of selected wood materials as determined by heat release, mass loss and charring rates. Thick samples of redwood, southern pine, red oak and basswood were tested in a heat release rate calorimeter. Results on ignitability and average beat...

Influence of heat transmission mode on heating rates and on the selection of patches for heating in a mediterranean lizard.

PubMed

Belliure, Josabel; Carrascal, Luis M

2002-01-01

Heliothermy (heat gain by radiation) has been given a prominent role in basking lizards. However, thigmothermy (heat gain by conduction) could be relevant for heating in small lizards. To ascertain the importance of the different heat transmission modes to the thermoregulatory processes, we conducted an experimental study where we analyzed the role of heat transmission modes on heating rates and on the selection of sites for heating in the Mediterranean lizard Acanthodactylus erythrurus (Lacertidae). The study was conducted under laboratory conditions, where two situations of different operative temperatures (38 degrees and 50 degrees C) were simulated in a terrarium. In a first experiment, individuals were allowed to heat up during 2 min at both temperatures and under both heat transmission modes. In a second experiment, individuals were allowed to select between patches differing in the main transmission mode, at both temperatures, to heat up. Experiences were conducted with live, nontethered lizards with a starting body temperature of 27 degrees C. Temperature had a significant effect on the heating rate, with heat gain per unit of time being faster at the higher operative temperature (50 degrees C). The effect of the mode of heat transmission on the heating rate was also significant: at 50 degrees C, heating rate was greater when the main heat transmission mode was conduction from the substrate (thigmothermy) than when heating was mainly due to heat gain by radiation (heliothermy); at 38 degrees C, heating rates did not significantly differ between transmission modes. At 38 degrees C, selection of the site for heating was not significantly different from that expected by chance. However, at 50 degrees C, the heating site offering the slowest heating rate (heliothermic patch) was selected. These results show that heating rates vary not only with environmental temperature but also with different predominant heat transmission modes. Lizards are able to identify

The clinical potential of ramosetron in the treatment of irritable bowel syndrome with diarrhea (IBS-D).

PubMed

Min, Yang Won; Rhee, Poong-Lyul

2015-05-01

Irritable bowel syndrome (IBS) is a highly prevalent functional bowel disorder. Serotonin (5-HT) is known to play a physiological and pathophysiological role in the regulation of gastrointestinal function. In experimental studies, 5-HT3 receptor antagonists have been reported to slow colon transit, to blunt gastrocolonic reflex, and to reduce rectal sensitivity. Alosetron and cilansetron, potent and selective 5-HT3 receptor antagonists, have proven efficacy in the treatment of IBS with diarrhea (IBS-D). However, alosetron was voluntarily withdrawn due to postmarketing reports of ischemic colitis and complications of constipation, and cilansetron was never marketed. Currently alosetron is available under a risk management program for women with severe IBS-D. Ramosetron is another potent and selective 5-HT3 receptor antagonist, which has been marketed in Japan, South Korea, and Taiwan. In animal studies, ramosetron reduced defecation induced by corticotrophin-releasing hormone and had inhibitory effects on colonic nociception. In two randomized controlled studies including 957 patients with IBS-D, ramosetron increased monthly responder rates of patient-reported global assessment of IBS symptom relief compared with placebo. Ramosetron was also as effective as mebeverine in male patients with IBS-D. In a recent randomized controlled trial with 343 male patients with IBS-D, ramosetron has proved effective in improving stool consistency, relieving abdominal pain/discomfort, and improving health-related quality of life. Regarding safety, ramosetron is associated with a lower incidence of constipation compared with other 5-HT3 receptor antagonists and has not been associated with ischemic colitis. Although further large prospective studies are needed to assess whether ramosetron is effective for female patients with IBS-D and to evaluate its long-term safety, ramosetron appears to be one of the most promising agents for patients with IBS-D.

The fundamental ribosomal RNA transcription initiation factor-IB (TIF-IB, SL1, factor D) binds to the rRNA core promoter primarily by minor groove contacts.

PubMed

Geiss, G K; Radebaugh, C A; Paule, M R

1997-11-14

Acanthamoeba castellanii transcription initiation factor-IB (TIF-IB) is the TATA-binding protein-containing transcription factor that binds the rRNA promoter to form the committed complex. Minor groove-specific drugs inhibit TIF-IB binding, with higher concentrations needed to disrupt preformed complexes because of drug exclusion by bound TIF-IB. TIF-IB/DNA interactions were mapped by hydroxyl radical and uranyl nitrate footprinting. TIF-IB contacts four minor grooves in its binding site. TIF-IB and DNA wrap around each other in a right-handed superhelix of high pitch, so the upstream and downstream contacts are on opposite faces of the helix. Dimethyl sulfate protection assays revealed limited contact with a few guanines in the major groove. This detailed analysis suggests significant DNA conformation dependence of the interaction.

IBS Treatment Options

MedlinePlus

... also consider... The use and benefits offered by cognitive-behavioral therapy Consulting with your doctor about the use of ... Medications Probiotics and Antibiotics Psychological Treatments Understanding Stress Cognitive Behavioral Therapy Relaxation Techniques for IBS Take Part in Online ...

Deficiency in endogenous modulation of prolonged heat pain in patients with Irritable Bowel Syndrome and Temporomandibular Disorder

PubMed Central

King, Christopher D.; Wong, Fong; Currie, Tom; Mauderli, Andre P.; Fillingim, Roger B.; Riley, Joseph L.

2013-01-01

Females with Irritable Bowel Syndrome (IBS) and Temporomandibular Disorder (TMD) are characterized by enhanced sensitivity to experimental pain. One possible explanation for this observation is deficiencies in pain modulation systems like Diffuse Noxious Inhibitory Control (DNIC). In a few studies that used brief stimuli, chronic pain patients demonstrate reduced DNIC. The purpose of this study was to compare sensitivity to prolonged heat pain and the efficacy of DNIC in controls to IBS and TMD patients. Heat pain (experimental stimulus; 44.0-49.0°C), which was applied to left palm, was continuously rated during three 30-second trials across three separate testing sessions under the following conditions: without a conditioning stimulus; during concurrent immersion of the right foot in a 23.0°C (control); and during noxious cold immersion in a (DNIC; 8.0-16.0°C) water bath. Compared to controls, IBS and TMD patients reported increased sensitivity to heat pain and failed to demonstrate pain inhibition due to DNIC. Controls showed a significant reduction in pain during the DNIC session. These findings support the idea that chronic pain patients are not only more pain sensitive and demonstrate reduced pain inhibition by pain, possibly because of dysfunction of endogenous pain inhibition systems. PMID:19278784

IBS-like symptoms in patients with ulcerative colitis

PubMed Central

Gracie, David J; Ford, Alexander C

2015-01-01

Ulcerative colitis (UC) and irritable bowel syndrome (IBS) are chronic gastrointestinal disorders that, until recently, have been considered dichotomous conditions falling on either side of a functional-organic divide. However, persistent gastrointestinal symptoms, akin to those of IBS, are observed in up to one in three patients with quiescent UC. Whether these lower gastrointestinal symptoms are secondary to coexistent IBS or occult UC disease activity is uncertain, but when objective evidence of disease activity is lacking, escalation of conventional pharmacotherapy in such patients is often ineffective. The etiologies of both UC and IBS remain unclear, but dysregulation of the enteric nervous system, an altered microbiome, low-grade mucosal inflammation, and activation of the brain–gut axis is common to both; this suggests that some overlap between the two conditions is plausible. How best to investigate and manage IBS-type symptoms in UC patients remains unclear. Studies that have assessed patients with UC who meet criteria for IBS for subclinical inflammation have been conflicting in their results. Although evidence-based treatments for IBS exist, their efficacy in UC patients reporting these types of symptoms remains unclear. Given the disturbances in gut microbiota in UC, and the possible role of the brain–gut axis in the generation of such symptoms, treatments such as probiotics, fecal transfer, antidepressants, or psychological therapies would seem logical approaches to use in this group of patients. However, there are only limited data for all of these therapies; this suggests that randomized controlled trials to investigate their efficacy in this setting may be warranted. PMID:25733921

IBS-like symptoms in patients with ulcerative colitis.

PubMed

Gracie, David J; Ford, Alexander C

2015-01-01

Ulcerative colitis (UC) and irritable bowel syndrome (IBS) are chronic gastrointestinal disorders that, until recently, have been considered dichotomous conditions falling on either side of a functional-organic divide. However, persistent gastrointestinal symptoms, akin to those of IBS, are observed in up to one in three patients with quiescent UC. Whether these lower gastrointestinal symptoms are secondary to coexistent IBS or occult UC disease activity is uncertain, but when objective evidence of disease activity is lacking, escalation of conventional pharmacotherapy in such patients is often ineffective. The etiologies of both UC and IBS remain unclear, but dysregulation of the enteric nervous system, an altered microbiome, low-grade mucosal inflammation, and activation of the brain-gut axis is common to both; this suggests that some overlap between the two conditions is plausible. How best to investigate and manage IBS-type symptoms in UC patients remains unclear. Studies that have assessed patients with UC who meet criteria for IBS for subclinical inflammation have been conflicting in their results. Although evidence-based treatments for IBS exist, their efficacy in UC patients reporting these types of symptoms remains unclear. Given the disturbances in gut microbiota in UC, and the possible role of the brain-gut axis in the generation of such symptoms, treatments such as probiotics, fecal transfer, antidepressants, or psychological therapies would seem logical approaches to use in this group of patients. However, there are only limited data for all of these therapies; this suggests that randomized controlled trials to investigate their efficacy in this setting may be warranted.

B-ducted Heating of Black Widow Companions

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

Sanchez, Nicolas; Romani, Roger W., E-mail: rwr@astro.stanford.edu

The companions of evaporating binary pulsars (black widows and related systems) show optical emission suggesting strong heating. In a number of cases, large observed temperatures and asymmetries are inconsistent with direct radiative heating for the observed pulsar spindown power and expected distance. Here we describe a heating model in which the pulsar wind sets up an intrabinary shock (IBS) against the companion wind and magnetic field, and a portion of the shock particles duct along this field to the companion magnetic poles. We show that a variety of heating patterns, and improved fits to the observed light curves, can bemore » obtained at expected pulsar distances and luminosities, at the expense of a handful of model parameters. We test this “IBS-B” model against three well-observed binaries and comment on the implications for system masses.« less

A Swedish national adoption study of risk of irritable bowel syndrome (IBS).

PubMed

Waehrens, Rasmus; Zöller, Bengt; Sundquist, Jan; Sundquist, Kristina; Pirouzifard, MirNabi

2017-01-01

Irritable bowel syndrome (IBS) clusters in families, but the familial risk of IBS has not been determined in adoptees. Studying adoptees and their biological and adoptive parents is a strong study design for separating genetic from environmental causes of familial clustering. This nationwide study aimed to separate the biological (genetic) and familial environmental contribution to the familial transmission of IBS. We performed a family study for Swedish-born adoptees born from 1951 until 1995, and their biological and adoptive parents. The Swedish Multigeneration Register was linked to the Hospital Register (inpatients and outpatients) for the period 1964-2012 and the Swedish Outpatient Care Register for 2001-2012, and the Swedish Primary Healthcare register for 1989-2012. ORs for IBS were calculated for adoptees with an affected biological parent with IBS compared with adoptees without a biological parent with IBS. The OR for IBS was also determined in adoptees with an adoptive parent with IBS compared with adoptees without an adoptive parent with IBS. Heritability h 2 (±SE) was also determined. The ORs for IBS were 1.67 in adoptees (95% CI 1.06 to 2.62) of biological parents diagnosed with IBS. The ORs for IBS were 0.88 in adoptees (95% CI 0.48 to 1.63) of adoptive parents diagnosed with IBS. The heritability was 19.5%±8.5%. The present study indicates that biological (genetic) factors are important for the familial clustering of IBS. The heritability calculated is in the range from twin studies and suggests that heritability may be estimated in adoptees.

Exclusion of the GNAS locus in PHP-Ib patients with broad GNAS methylation changes: evidence for an autosomal recessive form of PHP-Ib?

PubMed

Fernández-Rebollo, Eduardo; Pérez de Nanclares, Guiomar; Lecumberri, Beatriz; Turan, Serap; Anda, Emma; Pérez-Nanclares, Gustavo; Feig, Denice; Nik-Zainal, Serena; Bastepe, Murat; Jüppner, Harald

2011-08-01

Most patients with autosomal dominant pseudohypoparathyroidism type Ib (AD-PHP-Ib) carry maternally inherited microdeletions upstream of GNAS that are associated with loss of methylation restricted to GNAS exon A/B. Only few AD-PHP-Ib patients carry microdeletions within GNAS that are associated with loss of all maternal methylation imprints. These epigenetic changes are often indistinguishable from those observed in patients affected by an apparently sporadic PHP-Ib form that has not yet been defined genetically. We have now investigated six female patients affected by PHP-Ib (four unrelated and two sisters) with complete or almost complete loss of GNAS methylation, whose healthy children (11 in total) showed no epigenetic changes at this locus. Analysis of several microsatellite markers throughout the 20q13 region made it unlikely that PHP-Ib is caused in these patients by large deletions involving GNAS or by paternal uniparental isodisomy or heterodisomy of chromosome 20 (patUPD20). Microsatellite and single-nucleotide variation (SNV) data revealed that the two affected sisters share their maternally inherited GNAS alleles with unaffected relatives that lack evidence for abnormal GNAS methylation, thus excluding linkage to this locus. Consistent with these findings, healthy children of two unrelated sporadic PHP-Ib patients had inherited different maternal GNAS alleles, also arguing against linkage to this locus. Based on our data, it appears plausible that some forms of PHP-Ib are caused by homozygous or compound heterozygous mutation(s) in an unknown gene involved in establishing or maintaining GNAS methylation. Copyright © 2011 American Society for Bone and Mineral Research.

Exclusion of the GNAS Locus in PHP-Ib Patients With Broad GNAS Methylation Changes: Evidence for an Autosomal Recessive Form of PHP-Ib?

PubMed Central

Fernández-Rebollo, Eduardo; de Nanclares, Guiomar Pérez; Lecumberri, Beatriz; Turan, Serap; Anda, Emma; Pérez-Nanclares, Gustavo; Feig, Denice; Nik-Zainal, Serena; Bastepe, Murat; Jüppner, Harald

2013-01-01

Most patients with autosomal dominant pseudohypoparathyroidism type Ib (AD-PHP-Ib) carry maternally inherited microdeletions upstream of GNAS that are associated with loss of methylation restricted to GNAS exon A/B. Only few AD-PHP-Ib patients carry microdeletions within GNAS that are associated with loss of all maternal methylation imprints. These epigenetic changes are often indistinguishable from those observed in patients affected by an apparently sporadic PHP-Ib form that has not yet been defined genetically. We have now investigated six female patients affected by PHP-Ib (four unrelated and two sisters) with complete or almost complete loss of GNAS methylation, whose healthy children (11 in total) showed no epigenetic changes at this locus. Analysis of several microsatellite markers throughout the 20q13 region made it unlikely that PHP-Ib is caused in these patients by large deletions involving GNAS or by paternal uniparental isodisomy or heterodisomy of chromosome 20 (patUPD20). Microsatellite and single-nucleotide variation (SNV) data revealed that the two affected sisters share their maternally inherited GNAS alleles with unaffected relatives that lack evidence for abnormal GNAS methylation, thus excluding linkage to this locus. Consistent with these findings, healthy children of two unrelated sporadic PHP-Ib patients had inherited different maternal GNAS alleles, also arguing against linkage to this locus. Based on our data, it appears plausible that some forms of PHP-Ib are caused by homozygous or compound heterozygous mutation(s) in an unknown gene involved in establishing or maintaining GNAS methylation. PMID:21523828

Integrals for IBS and beam cooling

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

Burov, A.; /Fermilab

Simulation of beam cooling usually requires performing certain integral transformations every time step or so, which is a significant burden on the CPU. Examples are the dispersion integrals (Hilbert transforms) in the stochastic cooling, wake fields and IBS integrals. An original method is suggested for fast and sufficiently accurate computation of the integrals. This method is applied for the dispersion integral. Some methodical aspects of the IBS analysis are discussed.

Integrals for IBS and Beam Cooling

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

Burov, A.

Simulation of beam cooling usually requires performing certain integral transformations every time step or so, which is a significant burden on the CPU. Examples are the dispersion integrals (Hilbert transforms) in the stochastic cooling, wake fields and IBS integrals. An original method is suggested for fast and sufficiently accurate computation of the integrals. This method is applied for the dispersion integral. Some methodical aspects of the IBS analysis are discussed.

Possible Involvement of Avoidant Attachment Style in the Relations Between Adult IBS and Reported Separation Anxiety in Childhood.

PubMed

Ben-Israel, Yuval; Shadach, Eran; Levy, Sigal; Sperber, Ami; Aizenberg, Dov; Niv, Yaron; Dickman, Ram

2016-12-01

Irritable bowel syndrome (IBS) in adults as well as separation anxiety disorder (SAD) and recurrent abdominal pain (RAP) in childhood are associated with anxiety and somatization. Our aim was to examine possible associations between IBS in adulthood and SAD in childhood. Patients with IBS and healthy subjects completed a demographic questionnaire, the Separation Anxiety Symptom Inventory (SASI), the Somatization Subscale of Symptom Checklist-90-R (SCL-90-R), the Attachment Style Questionnaire, and a retrospective self-report questionnaire regarding RAP. Compared with controls, patients with IBS were characterized by an avoidant attachment style and scored higher on the SCL-90-R scale regarding the tendency to somatization (25.35 ± 7.47 versus16.50 ± 4.40, p < 0.001). More patients with IBS (25% versus 7.5%) reported RAP in childhood, but contrary to prediction, also had significantly lower SASI scores. Adults with IBS were characterized by somatization, insecure attachment style and recalled higher rates of RAP and surprisingly less symptoms of SAD in childhood. Based on these results, an etiological model for IBS is suggested, in which an avoidant attachment style and a tendency to somatization play an important role in the development of IBS. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

A Swedish national adoption study of risk of irritable bowel syndrome (IBS)

PubMed Central

Waehrens, Rasmus; Sundquist, Jan; Sundquist, Kristina; Pirouzifard, MirNabi

2017-01-01

Objectives Irritable bowel syndrome (IBS) clusters in families, but the familial risk of IBS has not been determined in adoptees. Studying adoptees and their biological and adoptive parents is a strong study design for separating genetic from environmental causes of familial clustering. This nationwide study aimed to separate the biological (genetic) and familial environmental contribution to the familial transmission of IBS. Methods We performed a family study for Swedish-born adoptees born from 1951 until 1995, and their biological and adoptive parents. The Swedish Multigeneration Register was linked to the Hospital Register (inpatients and outpatients) for the period 1964–2012 and the Swedish Outpatient Care Register for 2001–2012, and the Swedish Primary Healthcare register for 1989–2012. ORs for IBS were calculated for adoptees with an affected biological parent with IBS compared with adoptees without a biological parent with IBS. The OR for IBS was also determined in adoptees with an adoptive parent with IBS compared with adoptees without an adoptive parent with IBS. Heritability h 2 (±SE) was also determined. Results The ORs for IBS were 1.67 in adoptees (95% CI 1.06 to 2.62) of biological parents diagnosed with IBS. The ORs for IBS were 0.88 in adoptees (95% CI 0.48 to 1.63) of adoptive parents diagnosed with IBS. The heritability was 19.5%±8.5%. Conclusions The present study indicates that biological (genetic) factors are important for the familial clustering of IBS. The heritability calculated is in the range from twin studies and suggests that heritability may be estimated in adoptees. PMID:29119001

A prospective study of the psychobehavioral factors responsible for a change from non-patient irritable bowel syndrome to IBS patient status

PubMed Central

Fujii, Yasushi; Nomura, Shinobu

2008-01-01

Background To investigate non-patient irritable bowel syndrome (IBS) change to IBS and to determine factors predictive of the onset of IBS, individual biological factors, psychological factors, behavioral factors, and environmental factors were examined. Methods The subjects were 105 non-patient IBS (male = 59, female = 46, average age:21.49 ± 2.37), including 68 of the diarrhea-predominant type and 37 of the constipation-predominant type selected from 1,409 university and technical college students by use of a questionnaire based on the Rome II diagnostic criteria. The subjects were followed for three years, and various characteristics and IBS symptoms were serially observed (12 times). The IBS incidence rate was calculated. Results During the three years, 37 non-patient IBS (35.24%) changed to IBS: 28 diarrhea-predominant type and 9 constipation-predominant type. All IBS symptoms disappeared in 26 non-patient IBS subjects (24.76%). According to quantification method II (discriminant analysis), seven factors (stressor, two kinds of stress coping styles, cognitive appraisal, eating habits, sleeping time, and psychologically abuse) were adopted as a predictive model for IBS incidence and were confirmed as predictive of IBS. Conclusion The results of this research show that non-patient IBS is a changeable state that can change into IBS or persons without symptoms. Most of the non-patient IBS subjects who became asymptomatic had had symptoms for six months or less. Furthermore, the longer a non-patient IBS subject had symptoms, the higher the risk of a change to IBS became. The findings suggest the usefulness of identifying and approaching non-patient IBS as early as possible to prevent the onset of IBS. It must be noted that the persons surveyed in the present study had only the diarrhea-predominant and constipation-predominant types. Therefore, the findings of the present study are limited only these two types. Further study including the mixed type is needed. PMID

Convective Heat Transfer Scaling of Ignition Delay and Burning Rate with Heat Flux and Stretch Rate in the Equivalent Low Stretch Apparatus

NASA Technical Reports Server (NTRS)

Olson, Sandra

2011-01-01

To better evaluate the buoyant contributions to the convective cooling (or heating) inherent in normal-gravity material flammability test methods, we derive a convective heat transfer correlation that can be used to account for the forced convective stretch effects on the net radiant heat flux for both ignition delay time and burning rate. The Equivalent Low Stretch Apparatus (ELSA) uses an inverted cone heater to minimize buoyant effects while at the same time providing a forced stagnation flow on the sample, which ignites and burns as a ceiling fire. Ignition delay and burning rate data is correlated with incident heat flux and convective heat transfer and compared to results from other test methods and fuel geometries using similarity to determine the equivalent stretch rates and thus convective cooling (or heating) rates for those geometries. With this correlation methodology, buoyant effects inherent in normal gravity material flammability test methods can be estimated, to better apply the test results to low stretch environments relevant to spacecraft material selection.

Patient educational media preferences for information about irritable bowel syndrome (IBS).

PubMed

Halpert, Albena; Dalton, Christine B; Palsson, Olafur; Morris, Carolyn; Hu, Yuming; Bangdiwala, Shrikant; Hankins, Jane; Norton, Nancy; Drossman, Douglas A

2008-12-01

To identify the educational media preferences of patients with irritable bowel syndrome (IBS). The IBS-Patient Education Questionnaire (PEQ) was administered to a national sample of IBS patients. Frequencies of item endorsements were compared and meaningful clinical differences were used to identify differences among subgroups. 1,242 patients completed the survey, mean age 39.3 years, 85% female, IBS duration 6.9 years, 79% had seen an MD for IBS within 6 months, and 92.6% used the web for medical information. The most desired source of education was "my doctor" (68%), followed by Internet (62%) and brochure (45%). Notably, patients favored an increase in use of media in the future (past vs. future): doctor (43 vs. 68%); Internet (36 vs. 62%); and brochures (26 vs. 45%). IBS patients expect more education than they have received. Understanding IBS patients' learning preferences can be highly valuable in the development or implementation of educational interventions.

Blastocystis sp. in Irritable Bowel Syndrome (IBS)--Detection in Stool Aspirates during Colonoscopy.

PubMed

Ragavan, Nanthiney Devi; Kumar, Suresh; Chye, Tan Tian; Mahadeva, Sanjiv; Shiaw-Hooi, Ho

2015-01-01

Blastocystis is one of the most common gut parasites found in the intestinal tract of humans and animals. Its' association with IBS is controversial, possibly as a result of irregular shedding of parasites in stool and variation in stool detection. We aimed to screen for Blastocystis in colonic stool aspirate samples in adult patients with and without IBS undergoing colonoscopy for various indications and measure the interleukin levels (IL-8, IL-3 and IL-5). In addition to standard stool culture techniques, polymerase chain reaction (PCR) techniques were employed to detect and subtype Blastocystis. All the serum samples collected were subjected for ELISA studies to measure the interleukin levels (IL-8, IL-3 and IL-5). Among 109 (IBS n = 35 and non-IBS n = 74) adults, direct stool examination and culture of colonic aspirates were initially negative for Blastocystis. However, PCR analysis detected Blastocystis in 6 (17%) IBS and 4 (5.5%) non-IBS patients. In the six positive IBS patients by PCR method, subtype 3 was shown to be the most predominant (3/6: 50%) followed by subtype 4 (2/6; 33.3%) and subtype 5 (1/6; 16.6%). IL-8 levels were significantly elevated in the IBS Blasto group and IBS group (p<0.05) compared to non-IBS and non-IBS Blasto group. The level of IL-3 in were seen to be significantly higher in than IBS Blasto group and IBS group (p<0.05) compared to non-IBS. Meanwhile, the IL-5 levels were significantly higher in IBS Blasto group (p<0.05) compared to non-IBS and non-IBS Blasto group. This study implicates that detecting Blastosystis by PCR method using colonic aspirate samples during colonoscopy, suggests that this may be a better method for sample collection due to the parasite's irregular shedding in Blastocystis-infected stools. Patients with IBS infected with parasite showed an increase in the interleukin levels demonstrate that Blastocystis does have an effect in the immune system.

Motility response to colonic distention is increased in postinfectious irritable bowel syndrome (PI-IBS).

PubMed

Kanazawa, M; Palsson, O S; van Tilburg, M A L; Gangarosa, L M; Fukudo, S; Whitehead, W E

2014-05-01

Acute intestinal infection leads to persistent intestinal smooth muscle hypercontractility and pain hypersensitivity after resolution of the infection in animal models. We investigated whether postinfectious irritable bowel syndrome (PI-IBS) is associated with abnormalities in phasic contractions of the colon, smooth muscle tone, and pain sensitivity compared to non-PI-IBS (NI-IBS) or healthy controls (HC). Two hundred and eighteen Rome III-positive IBS patients and 43 HC participated. IBS patients were designated PI-IBS, if their IBS symptoms began following an episode of gastroenteritis characterized by two or more of: fever, vomiting, or diarrhea. Pain threshold to phasic distentions of the descending colon was assessed using a barostat. Colonic motility was assessed with the barostat bag minimally inflated to the individual operating pressure (IOP), at 20 mmHg above the IOP, and following a test meal. IBS symptom severity and psychological symptoms were assessed by the IBS Severity Scale (IBS-SS) and the Brief Symptom Inventory-18 (BSI-18). Twenty two (10.1%) met criteria for PI-IBS. Both IBS and HC groups showed a significant increase in motility index during intraluminal distention and following meals. The magnitude of the response to distention above (orad to) the balloon was significantly greater in PI-IBS compared with NI-IBS (p < 0.05) or HC (p < 0.01). Differences between PI-IBS and NI-IBS were not significant for IBS symptom severity, pain threshold, barostat bag volumes, or any psychological score on the BSI-18. Patients with PI-IBS have greater colonic hypercontractility than NI-IBS. We speculate that sustained mild mucosal inflammation may cause this colonic irritability. © 2014 John Wiley & Sons Ltd.

Spatially resolved heat release rate measurements in turbulent premixed flames

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

Ayoola, B.O.; Kaminski, C.F.; Balachandran, R.

Heat release rate is a fundamental property of great importance for the theoretical and experimental elucidation of unsteady flame behaviors such as combustion noise, combustion instabilities, and pulsed combustion. Investigations of such thermoacoustic interactions require a reliable indicator of heat release rate capable of resolving spatial structures in turbulent flames. Traditionally, heat release rate has been estimated via OH or CH radical chemiluminescence; however, chemiluminescence suffers from being a line-of-sight technique with limited capability for resolving small-scale structures. In this paper, we report spatially resolved two-dimensional measurements of a quantity closely related to heat release rate. The diagnostic technique usesmore » simultaneous OH and CH{sub 2}O planar laser-induced fluorescence (PLIF), and the pixel-by-pixel product of the OH and CH{sub 2}O PLIF signals has previously been shown to correlate well with local heat release rates. Results from this diagnostic technique, which we refer to as heat release rate imaging (HR imaging), are compared with traditional OH chemiluminescence measurements in several flames. Studies were performed in lean premixed ethylene flames stabilized between opposed jets and with a bluff body. Correlations between bulk strain rates and local heat release rates were obtained and the effects of curvature on heat release rate were investigated. The results show that the heat release rate tends to increase with increasing negative curvature for the flames investigated for which Lewis numbers are greater than unity. This correlation becomes more pronounced as the flame gets closer to global extinction.« less

[Synthesis of exo-β-glucosaminidase BY FUNGUS Penicillium sp. IB-37-2].

PubMed

Aktuganov, G E; Galimzyanova, N F; Teregulova, G A; Melentjev, A I

2016-01-01

A new strain Penicillium sp. IB-37-2, which actively hydrolyzes chitosan (SD ∼80–85%) but possesses low activity against colloidal chitin, was isolated. The fungus was observed to have a high level chitosanase biosynthesis (1.5–3.0 U/mL) during submerged cultivation at 28°C, with a pH of 3.5–7.0 and 220 rpm in nutrient media containing chitosan or chitin from shells of crabs. Purification of the chitosanase enzyme complex from Penicillium sp. IB-37-2 by ultrafiltration and hydrophobic chromatography, followed by denaturing electrophoresis, revealed two predominant proteins with molecular weights of 89 and 41 kDa. The purified enzyme complex demonstrated maximal activity (maximal rate of hydrolysis of dissolved chitosan) and stability at 50–55°C and a pH of 3.5–4.0. The enzyme preparation also hydrolyzed laminarin, β-(1,3)-(1,4)-glycan, and colloidal chitin. Exohydrolysis of chitosan by the preparation isolated from Penicillium sp. IB-37-2 resulted in the formation of single product, D-glucosamine.

Pseudohypoparathyroidism type Ib associated with novel duplications in the GNAS locus.

PubMed

Perez-Nanclares, Gustavo; Velayos, Teresa; Vela, Amaya; Muñoz-Torres, Manuel; Castaño, Luis

2015-01-01

Pseudohypoparathyroidism type 1b (PHP-Ib) is characterized by renal resistance to PTH (and, sometimes, a mild resistance to TSH) and absence of any features of Albright's hereditary osteodystrophy. Patients with PHP-Ib suffer of defects in the methylation pattern of the complex GNAS locus. PHP-Ib can be either sporadic or inherited in an autosomal dominant pattern. Whereas familial PHP-Ib is well characterized at the molecular level, the genetic cause of sporadic PHP-Ib cases remains elusive, although some molecular mechanisms have been associated with this subtype. The aim of the study was to investigate the molecular and imprinting defects in the GNAS locus in two unrelated patients with PHP-Ib. We have analyzed the GNAS locus by direct sequencing, Methylation-Specific Multiplex Ligation-dependent Probe Amplification, microsatellites, Quantitative Multiplex PCR of Short Fluorescent fragments and array-Comparative Genomic Hybridization studies in order to characterize two unrelated families with clinical features of PHP-Ib. We identified two duplications in the GNAS region in two patients with PHP-Ib: one of them, comprising ∼ 320 kb, occurred 'de novo' in the patient, whereas the other one, of ∼ 179 kb in length, was inherited from the maternal allele. In both cases, no other known genetic cause was observed. In this article, we describe the to-our-knowledge biggest duplications reported so far in the GNAS region. Both are associated to PHP-Ib, one of them occurring 'de novo' and the other one being maternally inherited.

Post-infectious IBS, tropical sprue and small intestinal bacterial overgrowth: the missing link.

PubMed

Ghoshal, Uday C; Gwee, Kok-Ann

2017-07-01

Evidence is emerging that IBS, a hitherto enigmatic disorder thought to be predominantly related to psychological factors, has a microorganic basis in a subset of patients with the disease. Post-infectious IBS (PI-IBS), commonly of the diarrhoea-predominant subtype (defined as new development of IBS following acute infectious diarrhoea), is one such condition known to occur in up to 10-30% individuals after acute gastroenteritis. However, following acute infectious gastroenteritis, patients can also develop post-infectious malabsorption syndrome (PI-MAS), popularly known as tropical sprue. As no study on PI-IBS has rigorously excluded tropical sprue by appropriate investigations, including small intestinal biopsy, the frequency of tropical sprue among patients with PI-IBS is not known. Small intestinal bacterial overgrowth (SIBO) has been suggested to be associated with IBS in general, and in particular diarrhoea-predominant IBS, including PI-IBS. SIBO is also known to be associated with tropical sprue. As both IBS, particularly the subset probably associated with SIBO, and tropical sprue improve with antibiotic treatment, we provide evidence and an explanatory model to support a link among these disorders.

Integrated Baseline System (IBS), Version 1. 03. [Chemical Stockpile Emergency Preparedness Program

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

Bailey, B.M.; Burford, M.J.; Downing, T.R.

The Integrated Baseline System (IBS), operated by the Federal Emergency Management Agency (FEMA), is a system of computerized tools for emergency planing and analysis. This document is the user guide for the IBS and explains how to operate the IBS system. The fundamental function of the IBS is to provide tools that civilian emergency management personnel can use in developing emergency plans and in supporting emergency management activities to cope with a chemical-releasing event at a military chemical stockpile. Emergency management planners can evaluate concepts and ideas using the IBS system. The results of that experience can then be factoredmore » into refining requirements and plans. This document provides information for the general system user, and is the primary reference for the system features of the IBS. It is designed for persons who are familiar with general emergency management concepts, operations, and vocabulary. Although the IBS manual set covers basic and advanced operations, it is not a complete reference document set. Emergency situation modeling software in the IBS is supported by additional technical documents. Some of the other LBS software is commercial software for which more complete documentation is available. The IBS manuals reference such documentation where necessary. IBS is a dynamic system. Its capabilities are in a state of continuing expansion and enhancement.« less

Work Rate during Self-paced Exercise is not Mediated by the Rate of Heat Storage.

PubMed

Friesen, Brian J; Périard, Julien D; Poirier, Martin P; Lauzon, Martin; Blondin, Denis P; Haman, Francois; Kenny, Glen P

2018-01-01

To date, there have been mixed findings on whether greater anticipatory reductions in self-paced exercise intensity in the heat are mediated by early differences in rate of body heat storage. The disparity may be due to an inability to accurately measure minute-to-minute changes in whole-body heat loss. Thus, we evaluated whether early differences in rate of heat storage can mediate exercise intensity during self-paced cycling at a fixed rate of perceived exertion (RPE of 16; hard-to-very-hard work effort) in COOL (15°C), NORMAL (25°C), and HOT (35°C) ambient conditions. On separate days, nine endurance-trained cyclists exercised in COOL, NORMAL, and HOT conditions at a fixed RPE until work rate (measured after first 5 min of exercise) decreased to 70% of starting values. Whole-body heat loss and metabolic heat production were measured by direct and indirect calorimetry, respectively. Total exercise time was shorter in HOT (57 ± 20 min) relative to both NORMAL (72 ± 23 min, P = 0.004) and COOL (70 ± 26 min, P = 0.045). Starting work rate was lower in HOT (153 ± 31 W) compared with NORMAL (166 ± 27 W, P = 0.024) and COOL (170 ± 33 W, P = 0.037). Rate of heat storage was similar between conditions during the first 4 min of exercise (all P > 0.05). Thereafter, rate of heat storage was lower in HOT relative to NORMAL and COOL until 30 min of exercise (last common time-point between conditions; all P < 0.05). Further, rate of heat storage was significantly higher in COOL compared with NORMAL at 15 min (P = 0.026) and 20 min (P = 0.020) of exercise. No differences were measured at end exercise. We show that rate of heat storage does not mediate exercise intensity during self-paced exercise at a fixed RPE in cool to hot ambient conditions.

The impact of physical complaints, social environment, and psychological functioning on IBS patients' health perceptions: looking beyond GI symptom severity.

PubMed

Lackner, Jeffrey M; Gudleski, Gregory D; Thakur, Elyse R; Stewart, Travis J; Iacobucci, Gary J; Spiegel, Brennan Mr

2014-02-01

In the absence of a reliable biomarker, clinical decisions for a functional gastrointestinal (GI) disorder like irritable bowel syndrome (IBS) depend on asking patients to appraise and communicate their health status. Self-ratings of health (SRH) have proven a powerful and consistent predictor of health outcomes, but little is known about how they relate to those relevant to IBS (e.g., quality of life (QOL), IBS symptom severity). This study examined what psychosocial factors, if any, predict SRH among a cohort of more severe IBS patients. Subjects included 234 Rome III-positive IBS patients (mean age=41 years, female=78%) without comorbid organic GI disease. Subjects were administered a test battery that included the IBS Symptom Severity Scale, Screening for Somatoform Symptoms, IBS Medical Comorbidity Inventory, SF-12 Vitality Scale, Perceived Stress Scale, Beck Depression Inventory, Trait Anxiety Inventory, and Negative Interactions Scale. Partial correlations identified somatization, depression, fatigue, stress, anxiety, and medical comorbidities as variables with the strongest correlations with SRH (r values=0.36-0.41, P values <0.05). IBS symptom severity was weakly associated with SRH (r=0.18, P<0.05). The final regression model explained 41.3% of the variance in SRH scores (F=8.49, P<0.001) with significant predictors including fatigue, medical comorbidities, somatization, and negative social interactions. SRH are associated with psychological (anxiety, stress, depression), social (negative interactions), and extraintestinal somatic factors (fatigue, somatization, medical comorbidities). The severity of IBS symptoms appears to have a relatively modest role in how IBS patients describe their health in general.

IBS FOR ION DISTRIBUTION UNDER ELECTRON COOLING.

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

FEDOTOV,A.V.; BEN-ZVI,I.; EIDELMAN, YU.

Standard models of the intra-beam scattering (IBS) are based on the growth of the rms beam parameters for a Gaussian distribution. As a result of electron cooling, the core of beam distribution is cooled much faster than the tails, producing a denser core. In this paper, we compare various approaches to IBS treatment for such distribution. Its impact on the luminosity is also discussed.

New insights into visceral hypersensitivity —clinical implications in IBS

PubMed Central

Zhou, QiQi; Verne, G. Nicholas

2012-01-01

A subset of patients with IBS have visceral hypersensitivity and/or somatic hypersensitivity. Visceral hypersensitivity might have use as a clinical marker of IBS and could account for symptoms of urgency for bowel movements, bloating and abdominal pain. The mechanisms that lead to chronic visceral hypersensitivity in patients who have IBS are unclear. However, several working models may be considered, including: nociceptive input from the colon that leads to hypersensitivity; increased intestinal permeability that induces a visceral nociceptive drive; and alterations in the expression of microRNAs in gastrointestinal tissue that might be delivered via blood microvesicles to other target organs, such as the peripheral and/or central nervous system. As such, the chronic visceral hypersensitivity that is present in a subset of patients with IBS might be maintained by both peripheral and central phenomena. The theories underlying the development of chronic visceral hypersensitivity in patients with IBS are supported by findings from new animal models in which hypersensitivity follows transient inflammation of the colon. The presence of somatic hypersensitivity and an alteration in the neuroendocrine system in some patients who have IBS suggests that multisystemic factors are involved in the overall disorder. Thus, IBS is similar to other chronic pain disorders, such as fibromyalgia, chronic regional pain disorder and temporomandibular joint disorder, as chronic nociceptive mechanisms are activated in all of these disorders. PMID:21643039

Emerging treatments in neurogastroenterology: eluxadoline - a new therapeutic option for diarrhea-predominant IBS.

PubMed

Lacy, B E

2016-01-01

Irritable bowel syndrome (IBS) is the most common functional gastrointestinal disorder worldwide. The global prevalence of IBS is estimated to be as high as 15%. For many patients, IBS is a chronic disorder which can significantly reduce quality of life. Just as important as the effects on any one individual, IBS also places a significant impact on the population as a whole with its negative effects on the health care system. Irritable bowel syndrome is categorized into one of three main categories: IBS with diarrhea, IBS with constipation, and IBS with mixed bowel habits. Patients with diarrhea-predominant IBS (IBS-D) comprise a substantial proportion of the overall IBS population. A number of therapeutic options exist to treat the symptoms of abdominal pain, bloating, diarrhea, and fecal urgency, including non-pharmacologic therapies such as dietary changes and probiotics, or pharmacologic therapies such as loperamide and alosetron. However, many patients have persistent symptoms despite these therapies. This unmet need led to the development of eluxadoline, a mu-opioid receptor agonist/delta-opioid receptor antagonist/kappa-receptor agonist. Approved by the FDA in May 2015, this medication shows promise in the treatment of diarrhea-predominant IBS for both men and women. This monograph will briefly review the impact of IBS, discuss current treatments for IBS-D, and then focus on the pharmacology, clinical efficacy and safety of eluxadoline. Potential mechanisms related to rare events of acute pancreatitis or elevated liver tests will be discussed. © 2015 John Wiley & Sons Ltd.

Quality of life in patients with Irritable Bowel Syndrome (IBS), assessed using the IBS-Quality of Life (IBS-QOL) measure after 4 and 8 weeks of treatment with mebeverine hydrochloride or pinaverium bromide: results of an international prospective observational cohort study in Poland, Egypt, Mexico and China.

PubMed

Hou, Xiaohua; Chen, Shengliang; Zhang, Yali; Sha, Weihong; Yu, Xiaofeng; Elsawah, Hesham; Afifi, Afifi Fahmy; El-Khayat, Hisham Raafat; Nouh, Alaa; Hassan, Mohamed Fathalla; Fatah, Ayman Abdel; Rucker Joerg, Isabel; Sánchez Núñez, Juan Manuel; Osthoff Rueda, Rodolfo; Jurkowska, Grazyna; Walczak, Michal; Malecka-Panas, Ewa; Linke, Krzysztof; Hartleb, Marek; Janssen-van Solingen, Gwendolyn

2014-11-01

Irritable Bowel Syndrome (IBS) has a substantial impact on health-related quality of life (HR-QoL) but high-quality data pre- and post-treatment using the IBS-Quality of Life (IBS-QOL) measure are limited. The objective of this study was to evaluate the changes from baseline of the IBS-QOL scores, symptom scores and health economic data in IBS patients, after 4 and 8 weeks of treatment with mebeverine hydrochloride or pinaverium bromide. This was a prospective observational cohort study in patients with IBS, diagnosed using the Rome III criteria in four countries (Poland, Egypt, Mexico and China). A total of 607 patients were enrolled. At baseline, the IBS-QOL total scores were 52.0 in Poland, 48.9 in Egypt, 51.9 in Mexico, 76.4 in China and 56.4 overall. Increases in IBS-QOL total score were statistically significant at Weeks 4 and 8 overall and in each country (overall: 11.8 at Week 4, 24.3 at Week 8; p < 0.001). Improvements were shown in all IBS-QOL subscales and scores. Symptoms and health economic outcomes were improved. Furthermore, the favourable safety profile of these treatments was confirmed in this study. This study demonstrated that IBS patients have a substantially reduced HR-QoL and that treatment with mebeverine hydrochloride or pinaverium bromide improved HR-QoL.

Randomised controlled trial of mesalazine in IBS

PubMed Central

Barbara, Giovanni; Cremon, Cesare; Annese, Vito; Basilisco, Guido; Bazzoli, Franco; Bellini, Massimo; Benedetti, Antonio; Benini, Luigi; Bossa, Fabrizio; Buldrini, Paola; Cicala, Michele; Cuomo, Rosario; Germanà, Bastianello; Molteni, Paola; Neri, Matteo; Rodi, Marcello; Saggioro, Alfredo; Scribano, Maria Lia; Vecchi, Maurizio; Zoli, Giorgio; Corinaldesi, Roberto; Stanghellini, Vincenzo

2016-01-01

Objective Low-grade intestinal inflammation plays a role in the pathophysiology of IBS. In this trial, we aimed at evaluating the efficacy and safety of mesalazine in patients with IBS. Design We conducted a phase 3, multicentre, tertiary setting, randomised, double-blind, placebo-controlled trial in patients with Rome III confirmed IBS. Patients were randomly assigned to either mesalazine, 800 mg, or placebo, three times daily for 12 weeks, and were followed for additional 12 weeks. The primary efficacy endpoint was satisfactory relief of abdominal pain/discomfort for at least half of the weeks of the treatment period. The key secondary endpoint was satisfactory relief of overall IBS symptoms. Supportive analyses were also performed classifying as responders patients with a percentage of affirmative answers of at least 75% or >75% of time. Results A total of 185 patients with IBS were enrolled from 21 centres. For the primary endpoint, the responder patients were 68.6% in the mesalazine group versus 67.4% in the placebo group (p=0.870; 95% CI −12.8 to 15.1). In explorative analyses, with the 75% rule or >75% rule, the percentage of responders was greater in the mesalazine group with a difference over placebo of 11.6% (p=0.115; 95% CI −2.7% to 26.0%) and 5.9% (p=0.404; 95% CI −7.8% to 19.4%), respectively, although these differences were not significant. For the key secondary endpoint, overall symptoms improved in the mesalazine group and reached a significant difference of 15.1% versus placebo (p=0.032; 95% CI 1.5% to 28.7%) with the >75% rule. Conclusions Mesalazine treatment was not superior than placebo on the study primary endpoint. However, a subgroup of patients with IBS showed a sustained therapy response and benefits from a mesalazine therapy. Trial registration number ClincialTrials.gov number, NCT00626288. PMID:25533646

Rate of Heat Release in Diesel Engines

DOT National Transportation Integrated Search

1977-10-01

In this report, the concept of heat release in diesel engines is compared with reaction rates in petrol engines as a means of describing combustion. The intimate relationships between heat release, cylinder pressure development and cylinder pressure ...

Integrated Baseline System (IBS) Version 2.0: Utilities Guide

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

Burford, M.J.; Downing, T.R.; Williams, J.R.

1994-03-01

The Integrated Baseline System (IBS) is an emergency management planning and analysis tool being developed under the direction of the US Army Nuclear and Chemical Agency. This Utilities Guide explains how you can use the IBS utility programs to manage and manipulate various kinds of IBS data. These programs include utilities for creating, editing, and displaying maps and other data that are referenced to geographic location. The intended audience for this document are chiefly data managers but also system managers and some emergency management planners and analysts.

Motility Response to Colonic Distention is Increased in Post-infectious Irritable Bowel Syndrome (PI-IBS)

PubMed Central

Kanazawa, Motoyori; Palsson, Olafur S.; van Tilburg, Miranda A.L.; Gangarosa, Lisa M.; Fukudo, Shin; Whitehead., William E.

2015-01-01

Background Acute intestinal infection leads to persistent intestinal smooth muscle hypercontractility and pain hypersensitivity after resolution of the infection in animal models. We investigated whether post-infectious irritable bowel syndrome (PI-IBS) is associated with abnormalities in phasic contractions of the colon, smooth muscle tone and pain sensitivity compared to non-PI-IBS (NI-IBS) or healthy controls (HC). Methods 218 Rome III positive IBS patients and 43 healthy controls participated. IBS patients were designated PI-IBS if their IBS symptoms began following an episode of gastroenteritis characterized by 2 or more of: fever, vomiting, or diarrhea. Pain threshold to phasic distentions of the descending colon was assessed using a barostat. Colonic motility was assessed with the barostat bag minimally inflated to the individual operating pressure (IOP), at 20 mmHg above the IOP, and following a test meal. IBS symptom severity and psychological symptoms were assessed by the IBS Severity Scale (IBS-SS) and the Brief Symptom Inventory-18 (BSI-18). Key Results Twenty-two (10.1%) met criteria for PI-IBS. Both IBS and HC groups showed a significant increase in motility index during intraluminal distention and following meals. The magnitude of the response to distention above (orad to) the balloon was significantly greater in PI-IBS compared with NI-IBS (p<0.05) or HC (p<0.01). Differences between PI-IBS and NI-IBS were not significant for IBS symptom severity, pain threshold, barostat bag volumes, or any psychological score on the BSI-18. Conclusions & Inferences Patients with PI-IBS have greater colonic hypercontractility than NI-IBS. We speculate that sustained mild mucosal inflammation may cause this colonic irritability. PMID:24602083

Advanced Coursework Rates by Ethnicity: An 11-Year, Statewide Analysis

ERIC Educational Resources Information Center

Fowler, Janis C.

2013-01-01

Purpose: The purpose of this study was to examine advanced coursework completion rates, Advanced Placement (AP)/International Baccalaureate (IB) testing rates, AP/IB exam passage rates, and the percentage of AP/IB exam scores at or above the criterion that may exist among Texas public high school students from 2001 to 2012 to ascertain (a) the…

Responders vs clinical response: a critical analysis of data from linaclotide phase 3 clinical trials in IBS-C.

PubMed

Lacy, B E; Lembo, A J; Macdougall, J E; Shiff, S J; Kurtz, C B; Currie, M G; Johnston, J M

2014-03-01

US Food and Drug Administration (FDA) set a rigorous standard for defining patient responders in irritable bowel syndrome-C (IBS-C; i.e., FDA's Responder Endpoint) for regulatory approval. However, this endpoint's utility for health-care practitioners to assess clinical response has not been determined. We analyzed pooled IBS-C linaclotide trial data to evaluate clinically significant responses in linaclotide-treated patients who did not meet the FDA responder definition. Percentages of FDA non-responders reporting improvement in abdominal pain, bowel function and/or global relief measures were determined using pooled data from two linaclotide Phase 3 IBS-C trials. 1602 IBS-C patients enrolled; 34% of linaclotide-treated and 17% of placebo-treated patients met the FDA Responder Endpoint (p < 0.0001). Among FDA non-responders at week 12, 63% of linaclotide-treated patients reported their abdominal pain was at least somewhat relieved, compared with 48% of placebo-treated patients. For stool frequency, 62% of linaclotide-treated patients reported that they were at least somewhat improved at week 12, compared with 46% of placebo-treated patients. For global IBS symptoms, 65% of linaclotide-treated patients reported at least some IBS-symptom relief, 43% reported adequate relief of IBS symptoms, and 57% reported being satisfied with linaclotide treatment, vs placebo rates of 48%, 34%, and 41% respectively. Most linaclotide-treated IBS-C patients who were FDA non-responders reported some improvement in abdominal pain and stool frequency, and global relief/satisfaction. In addition to the FDA Responder Endpoint, differing response thresholds and symptom-specific change from baseline should be considered by clinicians for a complete understanding of clinical response to linaclotide and other IBS-C therapies. © 2013 Ironwood Pharmaceuticals. Neurogastroenterology & Motility published by John Wiley & Sons Ltd.

Adjuvant chemotherapy with sequential cytokine-induced killer (CIK) cells in stage IB non-small cell lung cancer.

PubMed

Li, Da-Peng; Li, Wei; Feng, Jun; Chen, Kai; Tao, Min

2015-01-01

For non-small cell lung cancer (NSCLC) patients at stage IB, adjuvant chemotherapy does not improve survival. Evidence suggests that dendritic cell (DC)-activated cytokine-induced killer (DC-CIK) cell therapy in addition to chemotherapy improves survival for stage I-IIIA NSCLC patients after surgery, but there are not enough data to confirm this benefit specifically for those at stage IB. Herein, we retrospectively evaluated the efficacy and safety of this therapy administered to stage IB NSCLC patients. Sixty-six patients were treated with four-cycle adjuvant chemotherapy initiated 3 weeks after surgical resection. In addition, 28 of these patients underwent DC-CIK therapy on a trimonthly basis (average 3.1 times, range 1-6) beginning 1 month after chemotherapy. The disease-free survival (DFS) rates of the two groups were statistically similar, although patients who received DC-CIK therapy showed slightly higher 1- and 2-year DFS rates (100.0% and 96.4%, respectively, compared with 81.6% and 76.3%). More importantly, patients in the DC-CIK therapy group had significantly longer overall survival (p=0.018). For patients who received treatment after recurrence, the DC-CIK therapy group had longer progression-free survival compared with the chemotherapy-only group. In addition, patients given DC-CIK therapy experienced less fatigue and appetite loss. The rate of adverse side effects was similar between the two groups. In conclusion, for these stage IB NSCLC patients, DC-CIK therapy significantly improved 2-year DFS rates compared with those who received chemotherapy only. DC-CIK therapy also benefited patients' quality of life, and adverse events were acceptable.

Opsonophagocytic Antibodies to Serotype Ia, Ib, and III Group B Streptococcus among Korean Infants and in Intravenous Immunoglobulin Products.

PubMed

Kim, Han Wool; Lee, Ji Hyen; Cho, Hye Kyung; Lee, Hyunju; Seo, Ho Seong; Lee, Soyoung; Kim, Kyung Hyo

2017-05-01

Group B streptococcus (GBS) infection is a leading cause of sepsis and meningitis among infants, and is associated with high rates of morbidity and mortality in many countries. Protection against GBS typically involves antibody-mediated opsonization by phagocytes and complement components. The present study evaluated serotype-specific functional antibodies to GBS among Korean infants and in intravenous immunoglobulin (IVIG) products. An opsonophagocytic killing assay (OPA) was used to calculate the opsonization indices (OIs) of functional antibodies to serotypes Ia, Ib, and III in 19 IVIG products from 5 international manufacturers and among 98 Korean infants (age: 0-11 months). The GBS Ia, Ib, and III serotypes were selected because they are included in a trivalent GBS vaccine formulation that is being developed. The OI values for the IVIG products were 635-5,706 (serotype Ia), 488-1,421 (serotype Ib), and 962-3,315 (serotype III), and none of the IVIG lots exhibited undetectable OI values (< 4). The geometric mean OI values were similar for all 3 serotypes when we compared the Korean manufacturers. The seropositive rate among infants was significantly lower for serotype Ia (18.4%), compared to serotype Ib and serotype III (both, 38.8%). Infant age of ≥ 3 months was positively correlated with the seropositive rates for each serotype. Therefore, only a limited proportion of infants exhibited protective immunity against serotype Ia, Ib, and III GBS infections. IVIG products that exhibit high antibody titers may be a useful therapeutic or preventive measure for infants. Further studies are needed to evaluate additional serotypes and age groups. © 2017 The Korean Academy of Medical Sciences.

Opsonophagocytic Antibodies to Serotype Ia, Ib, and III Group B Streptococcus among Korean Infants and in Intravenous Immunoglobulin Products

PubMed Central

2017-01-01

Group B streptococcus (GBS) infection is a leading cause of sepsis and meningitis among infants, and is associated with high rates of morbidity and mortality in many countries. Protection against GBS typically involves antibody-mediated opsonization by phagocytes and complement components. The present study evaluated serotype-specific functional antibodies to GBS among Korean infants and in intravenous immunoglobulin (IVIG) products. An opsonophagocytic killing assay (OPA) was used to calculate the opsonization indices (OIs) of functional antibodies to serotypes Ia, Ib, and III in 19 IVIG products from 5 international manufacturers and among 98 Korean infants (age: 0–11 months). The GBS Ia, Ib, and III serotypes were selected because they are included in a trivalent GBS vaccine formulation that is being developed. The OI values for the IVIG products were 635–5,706 (serotype Ia), 488–1,421 (serotype Ib), and 962–3,315 (serotype III), and none of the IVIG lots exhibited undetectable OI values (< 4). The geometric mean OI values were similar for all 3 serotypes when we compared the Korean manufacturers. The seropositive rate among infants was significantly lower for serotype Ia (18.4%), compared to serotype Ib and serotype III (both, 38.8%). Infant age of ≥ 3 months was positively correlated with the seropositive rates for each serotype. Therefore, only a limited proportion of infants exhibited protective immunity against serotype Ia, Ib, and III GBS infections. IVIG products that exhibit high antibody titers may be a useful therapeutic or preventive measure for infants. Further studies are needed to evaluate additional serotypes and age groups. PMID:28378545

How Accessible Is IB Schooling? Evidence from Australia

ERIC Educational Resources Information Center

Dickson, Anisah; Perry, Laura B.; Ledger, Susan

2017-01-01

This study examines access to International Baccalaureate schools in Australia. It is important to examine whether, as a highly regarded form of rigorous academic education, IB programmes are available to a wide range of students. We examine the location of schools in Australia that offer one or more of the IB Primary Years Programme, Middle Years…

2-Alkynoic fatty acids inhibit topoisomerase IB from Leishmania donovani.

PubMed

Carballeira, Néstor M; Cartagena, Michelle; Sanabria, David; Tasdemir, Deniz; Prada, Christopher F; Reguera, Rosa M; Balaña-Fouce, Rafael

2012-10-01

2-Alkynoic fatty acids display antimycobacterial, antifungal, and pesticidal activities but their antiprotozoal activity has received little attention. In this work we synthesized the 2-octadecynoic acid (2-ODA), 2-hexadecynoic acid (2-HDA), and 2-tetradecynoic acid (2-TDA) and show that 2-ODA is the best inhibitor of the Leishmania donovani DNA topoisomerase IB enzyme (LdTopIB) with an EC(50)=5.3±0.7μM. The potency of LdTopIB inhibition follows the trend 2-ODA>2-HDA>2-TDA, indicating that the effectiveness of inhibition depends on the fatty acid carbon chain length. All of the studied 2-alkynoic fatty acids were less potent inhibitors of the human topoisomerase IB enzyme (hTopIB) as compared to LdTopIB. 2-ODA also displayed in vitro activity against Leishmania donovani (IC(50)=11.0μM), but it was less effective against other protozoa, Trypanosoma cruzi (IC(50)=48.1μM) and Trypanosoma brucei rhodesiense (IC(50)=64.5μM). The antiprotozoal activity of the 2-alkynoic fatty acids, in general, followed the trend 2-ODA>2-HDA>2-TDA. The experimental information gathered so far indicates that 2-ODA is a promising antileishmanial compound. Copyright © 2012 Elsevier Ltd. All rights reserved.

Low fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAP) diet improves symptoms in adults suffering from irritable bowel syndrome (IBS) compared to standard IBS diet: A meta-analysis of clinical studies.

PubMed

Varjú, Péter; Farkas, Nelli; Hegyi, Péter; Garami, András; Szabó, Imre; Illés, Anita; Solymár, Margit; Vincze, Áron; Balaskó, Márta; Pár, Gabriella; Bajor, Judit; Szűcs, Ákos; Huszár, Orsolya; Pécsi, Dániel; Czimmer, József

2017-01-01

Irritable bowel syndrome (IBS) and functional digestive tract disorders, e.g. functional bloating, carbohydrate maldigestion and intolerances, are very common disorders frequently causing significant symptoms that challenge health care systems. A low Fermentable Oligosaccharides, Disaccharides, Monosaccharides and Polyols (FODMAP) diet is one of the possible therapeutic approaches for decreasing abdominal symptoms and improving quality of life. We aimed to meta-analyze data on the therapeutic effect of a low-FODMAP diet on symptoms of IBS and quality of life and compare its effectiveness to a regular, standard IBS diet with high FODMAP content, using a common scoring system, the IBS Symptom Severity Score (IBS-SSS). A systematic literature search was conducted in PubMed, EMBASE and the Cochrane Library as well as in the references in a recent meta-analysis. Adult patients diagnosed with IBS according to the Rome II, Rome III, Rome IV or NICE criteria were included in the analysis. Mean differences with 95% confidence intervals were calculated from studies that contained means, standard deviation (SD) or mean differences and SD of differences and p-values. A random effect model was used because of the heterogeneity (Q test (χ2) and I2 indicator). A p-value of less than 0.05 was chosen to indicate a significant difference. The literature search yielded 902 publications, but only 10 were eligible for our meta-analysis. Both regular and low-FODMAP diets proved to be effective in IBS, but post-diet IBS-SSS values were significantly lower (p = 0.002) in the low-FODMAP group. The low-FODMAP diet showed a correlation with the improvement of general symptoms (by IBS-SSS) in patients with IBS. This meta-analysis provides high-grade evidence of an improved general symptom score among patients with irritable bowel syndrome who have maintained a low-FODMAP diet compared to those on a traditional IBS diet, therefore showing its superiority to regular IBS dietary therapy. These

HLA class Ib in pregnancy and pregnancy-related disorders.

PubMed

Persson, Gry; Melsted, Wenna Nascimento; Nilsson, Line Lynge; Hviid, Thomas Vauvert F

2017-08-01

The HLA class Ib genes, HLA-E, HLA-F, and HLA-G, were discovered long after the classical HLA class Ia genes. The elucidation of their functions had a modest beginning. However, their basic functions and involvement in pathophysiology and a range of diseases are now emerging. Although results from a range of studies support the functional roles for the HLA class Ib molecules in adult life, especially HLA-G and HLA-F have most intensively been, and were also primarily, studied in relation to reproduction and pregnancy. The expression of HLA class Ib proteins at the feto-maternal interface in the placenta seems to be important for the maternal acceptance of the semi-allogenic fetus. In contrast to the functions of HLA class Ia, HLA-G possesses immune-modulatory and tolerogenic functions. Here, we review an accumulating amount of data describing the functions of HLA class Ib molecules in relation to fertility, reproduction, and pregnancy, and a possible role for these molecules in certain pregnancy complications, such as implantation failure, recurrent spontaneous abortions, and pre-eclampsia. The results from different kinds of studies point toward a role for HLA class Ib, especially HLA-G, throughout the reproductive cycle from conception to the birth weight of the child.

Interaction between preprandial and postprandial rectal sensory and motor abnormalities in IBS.

PubMed

Törnblom, Hans; Van Oudenhove, Lukas; Tack, Jan; Simrén, Magnus

2014-09-01

Rectal sensory and motor interactions in patients with IBS have not been studied in detail. The aim of this study was to evaluate fasting and postprandial rectal sensorimotor characteristics and their interactions in IBS compared with healthy controls. We included 274 patients with IBS and 34 controls. All subjects underwent a rectal barostat study before and 60 min after a standardised liquid meal (800 kcal; 60% fat). Sensory thresholds, intensity of sensations, viscerosomatic referral and compliance were measured. During 15 min before the first distension sequence and until 50 min after meal intake, rectal balloon volumes were registered in 5 min intervals at operating pressure to quantify rectal tone. Mixed models were used to analyse the rectal tone response over time. Rectal sensory thresholds and compliance were decreased and viscerosomatic referral areas increased in patients with IBS compared with controls. Meal intake increased rectal sensitivity, compliance and referral areas in patients and controls and the same proportions of patients were hypersensitive to distension before and after meal intake. There was a higher basal rectal tone in IBS and a significantly different rectal tone response after meal intake in patients with IBS compared with controls and, interestingly, also in IBS with rectal hypersensitivity (defined in the preprandial state), compared with normosensitive patients. Meal intake affects rectal sensorimotor function in IBS and health. Importantly, the rectal tone responses to a high-caloric meal are different between patients with IBS and controls, as well as between hypersensitive and normosensitive patients with IBS. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Low fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAP) diet improves symptoms in adults suffering from irritable bowel syndrome (IBS) compared to standard IBS diet: A meta-analysis of clinical studies

PubMed Central

Varjú, Péter; Farkas, Nelli; Hegyi, Péter; Garami, András; Szabó, Imre; Illés, Anita; Solymár, Margit; Vincze, Áron; Balaskó, Márta; Pár, Gabriella; Bajor, Judit; Szűcs, Ákos; Huszár, Orsolya; Pécsi, Dániel

2017-01-01

Background Irritable bowel syndrome (IBS) and functional digestive tract disorders, e.g. functional bloating, carbohydrate maldigestion and intolerances, are very common disorders frequently causing significant symptoms that challenge health care systems. A low Fermentable Oligosaccharides, Disaccharides, Monosaccharides and Polyols (FODMAP) diet is one of the possible therapeutic approaches for decreasing abdominal symptoms and improving quality of life. Objectives We aimed to meta-analyze data on the therapeutic effect of a low-FODMAP diet on symptoms of IBS and quality of life and compare its effectiveness to a regular, standard IBS diet with high FODMAP content, using a common scoring system, the IBS Symptom Severity Score (IBS-SSS). Methods A systematic literature search was conducted in PubMed, EMBASE and the Cochrane Library as well as in the references in a recent meta-analysis. Adult patients diagnosed with IBS according to the Rome II, Rome III, Rome IV or NICE criteria were included in the analysis. Statistical methods Mean differences with 95% confidence intervals were calculated from studies that contained means, standard deviation (SD) or mean differences and SD of differences and p-values. A random effect model was used because of the heterogeneity (Q test (χ2) and I2 indicator). A p-value of less than 0.05 was chosen to indicate a significant difference. Results The literature search yielded 902 publications, but only 10 were eligible for our meta-analysis. Both regular and low-FODMAP diets proved to be effective in IBS, but post-diet IBS-SSS values were significantly lower (p = 0.002) in the low-FODMAP group. The low-FODMAP diet showed a correlation with the improvement of general symptoms (by IBS-SSS) in patients with IBS. Conclusions This meta-analysis provides high-grade evidence of an improved general symptom score among patients with irritable bowel syndrome who have maintained a low-FODMAP diet compared to those on a traditional IBS diet

Rate of precipitation of calcium phosphate on heated surfaces.

PubMed

Barton, K P; Chapman, T W; Lund, D

1985-03-01

Fouling of a heated stainless steel surface by calcium phosphate precipitation has been studied in an annular flow apparatus, instrumented to provide a constant heat flux while measuring local metal-surface temperatures. Models of the heat and mass-transfer boundary layers are used to estimate interfacial temperatures and concentrations, from which the heterogeneous reaction rate is inferred. The analysis indicates that the reaction rate is a function of both chemical kinetics and mass transfer limitations.

An algorithm for the kinetics of tire pyrolysis under different heating rates.

PubMed

Quek, Augustine; Balasubramanian, Rajashekhar

2009-07-15

Tires exhibit different kinetic behaviors when pyrolyzed under different heating rates. A new algorithm has been developed to investigate pyrolysis behavior of scrap tires. The algorithm includes heat and mass transfer equations to account for the different extents of thermal lag as the tire is heated at different heating rates. The algorithm uses an iterative approach to fit model equations to experimental data to obtain quantitative values of kinetic parameters. These parameters describe the pyrolysis process well, with good agreement (r(2)>0.96) between the model and experimental data when the model is applied to three different brands of automobile tires heated under five different heating rates in a pure nitrogen atmosphere. The model agrees with other researchers' results that frequencies factors increased and time constants decreased with increasing heating rates. The model also shows the change in the behavior of individual tire components when the heating rates are increased above 30 K min(-1). This result indicates that heating rates, rather than temperature, can significantly affect pyrolysis reactions. This algorithm is simple in structure and yet accurate in describing tire pyrolysis under a wide range of heating rates (10-50 K min(-1)). It improves our understanding of the tire pyrolysis process by showing the relationship between the heating rate and the many components in a tire that depolymerize as parallel reactions.

Kinetic effect of heating rate on the thermal maturity of carbonaceous material as an indicator of frictional heat during earthquakes

NASA Astrophysics Data System (ADS)

Kaneki, Shunya; Hirono, Tetsuro

2018-06-01

Because the maximum temperature reached in the slip zone is significant information for understanding slip behaviors during an earthquake, the maturity of carbonaceous material (CM) is widely used as a proxy for detecting frictional heat recorded by fault rocks. The degree of maturation of CM is controlled not only by maximum temperature but also by the heating rate. Nevertheless, maximum slip zone temperature has been estimated previously by comparing the maturity of CM in natural fault rocks with that of synthetic products heated at rates of about 1 °C s-1, even though this rate is much lower than the actual heating rate during an earthquake. In this study, we investigated the kinetic effect of the heating rate on the CM maturation process by performing organochemical analyses of CM heated at slow (1 °C s-1) and fast (100 °C s-1) rates. The results clearly showed that a higher heating rate can inhibit the maturation reactions of CM; for example, extinction of aliphatic hydrocarbon chains occurred at 600 °C at a heating rate of 1 °C s-1 and at 900 °C at a heating rate of 100 °C s-1. However, shear-enhanced mechanochemical effects can also promote CM maturation reactions and may offset the effect of a high heating rate. We should thus consider simultaneously the effects of both heating rate and mechanochemistry on CM maturation to establish CM as a more rigorous proxy for frictional heat recorded by fault rocks and for estimating slip behaviors during earthquake.

Comparison of the Rome IV and Rome III criteria for IBS diagnosis: A cross-sectional survey.

PubMed

Bai, Tao; Xia, Jing; Jiang, Yudong; Cao, Huan; Zhao, Yong; Zhang, Lei; Wang, Huan; Song, Jun; Hou, Xiaohua

2017-05-01

The aims of this study were to investigate the proportion of clinical irritable bowel syndrome (IBS) at a tertiary hospital in China, to compare the Rome III and Rome IV criteria with regard to IBS diagnosis, to describe the agreement between the Rome III and Rome IV criteria, and to identify differences between Rome IV-positive and -negative IBS patients. A cross-sectional survey was performed among outpatients in the gastrointestinal (GI) department of a tertiary hospital. The patients were categorized as having IBS using Rome III and Rome IV criteria. In total, 1,376 (91.7%) patients completed a GI symptom questionnaire. Among them, 352 were suspected of having IBS and 175 were diagnosed with IBS using the Rome III or Rome IV criteria. In particular, 170 (12.4%) patients were diagnosed with IBS using the Rome III criteria, and 84 (6.1%) patients were diagnosed using the Rome IV criteria. Rome IV IBS patients experienced more pain symptoms (P<0.01) and showed higher IBS severity scores. In contrast, no significant differences were noted for demographic characteristics, stool frequency, IBS subtype, disease course, operation history or GI infection history between Rome IV IBS patients and IBS patients not diagnosed with the Rome IV criteria. Rome IV-positive IBS patients represented approximately half of Rome III-positive IBS patients at a tertiary hospital in China. More specifically, Rome IV-positive IBS was mainly a subgroup of Rome III-positive IBS with more serious symptoms. © 2016 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

Integrated Baseline System (IBS), Version 1.03. User guide: Chemical Stockpile Emergency Preparedness Program

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

Bailey, B.M.; Burford, M.J.; Downing, T.R.

The Integrated Baseline System (IBS), operated by the Federal Emergency Management Agency (FEMA), is a system of computerized tools for emergency planing and analysis. This document is the user guide for the IBS and explains how to operate the IBS system. The fundamental function of the IBS is to provide tools that civilian emergency management personnel can use in developing emergency plans and in supporting emergency management activities to cope with a chemical-releasing event at a military chemical stockpile. Emergency management planners can evaluate concepts and ideas using the IBS system. The results of that experience can then be factoredmore » into refining requirements and plans. This document provides information for the general system user, and is the primary reference for the system features of the IBS. It is designed for persons who are familiar with general emergency management concepts, operations, and vocabulary. Although the IBS manual set covers basic and advanced operations, it is not a complete reference document set. Emergency situation modeling software in the IBS is supported by additional technical documents. Some of the other LBS software is commercial software for which more complete documentation is available. The IBS manuals reference such documentation where necessary. IBS is a dynamic system. Its capabilities are in a state of continuing expansion and enhancement.« less

New insights in IBS-like disorders: Pandora's box has been opened; a review.

PubMed

Borghini, Raffaele; Donato, Giuseppe; Alvaro, Domenico; Picarelli, Antonio

2017-01-01

The most complained gastrointestinal symptoms are chronic diarrhea, bloating and abdominal pain. Once malignancies and inflammatory bowel diseases are excluded, irritable bowel syndrome (IBS) and the so called "IBS-like disorders" should be taken into account. The relationship between IBS as defined by Rome IV criteria and these clinical conditions is sometimes obscure, since many IBS patients identify food as a possible trigger for their symptoms. Here, we discuss IBS and the most common IBS-like disorders (celiac disease, non-celiac gluten sensitivity, fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs), lactose intolerance, small intestinal bacterial overgrowth (SIBO), α-amylase/trypsin inhibitor (ATIs), nickel allergic contact mucositis), focusing on epidemiologic, clinical, diagnostic and therapeutic aspects. Given the lack of specificity of symptoms, clinical investigation will be facilitated by awareness of these disorders as well as new specific diagnostic tools.

Sparing bilateral neck level IB in oropharyngeal carcinoma and xerostomia outcomes.

PubMed

Tam, Moses; Riaz, Nadeem; Kannarunimit, Danita; Peña, Angela P; Schupak, Karen D; Gelblum, Daphna Y; Wolden, Suzanne L; Rao, Shyam; Lee, Nancy Y

2015-08-01

To assess whether sparing neck-level IB in target delineation of node-positive (N+) oropharyngeal carcinoma (OPC) can improve xerostomia outcomes without compromising locoregional control (LRC). A total of 125 N+ OPC patients with a median age of 57 years underwent chemoradiation between May 2010 and December 2011. A total of 74% of patients had T1-T2 disease, 26% T3-T4, 16% N1, 8% N2A, 48% N2B, 28% N2C; 53% base of tongue, 41% tonsil, and 6% other. Patients were divided into those who had target delineation sparing of bilateral level IB (the spared cohort) versus no sparing (the treated cohort). Sparing of contralateral high-level II nodes was also performed more consistently in the spared cohort. A prospective xerostomia questionnaire (patient reported) was given at each patient follow-up visit to this cohort of patients to assess late xerostomia. Clinical assessment (observer rated) at each patient follow-up visit was also recorded. The 2-year LRC for the spared and treated cohorts was 97.5% and 93.8%, respectively (median follow-up, 23.2 mo). No locoregional failures occurred outside of treatment fields. The spared cohort experienced significant benefits in patient-reported xerostomia summary scores (P=0.021) and observer-rated xerostomia scores (P=0.006). In addition, there were significant reductions in mean doses to the ipsilateral submandibular gland (63.9 vs. 70.5 Gy; P<0.001), contralateral submandibular gland (45.0 vs. 56.2 Gy; P<0.001), oral cavity (35.9 vs. 45.2 Gy; P<0.001), and contralateral parotid gland (20.0 vs. 24.4 Gy; P<0.001). Target delineation sparing of bilateral level IB nodes in N+ OPC reduced mean doses to salivary organs without compromising LRC. Patients with reduced target volumes had better patient-reported xerostomia outcomes.

Electron-impact excitation heating rates in the atmosphere of Titan

NASA Astrophysics Data System (ADS)

Campbell, L.; Kato, H.; Brunger, M. J.; Bradshaw, M. D.

2010-09-01

A previous study of various heating rates in the atmosphere of Titan included electron-impact excitation of molecular nitrogen as one component. This work examines this component in more detail, using a statistical equilibrium calculation to avoid approximations made in the earlier work. The sensitivity of the results to different cross-section sets is investigated. It is found that using recent and more physical cross sections for vibrational excitation produces a significant increase in the heating rate. On the other hand, using more accurate cross sections for the electronic states had little apparent effect on the heating rates when used within the approximations made in the previous model. However, the inclusion of more transitions in this study produces a significant increase in the electronic state heating rates, as states that were originally neglected are now accounted for here.

Therapeutic Potential of Zataria multiflora Boiss in Treatment of Irritable Bowel Syndrome (IBS).

PubMed

Mahboubi, Mohaddese

2018-01-15

Irritable Bowel syndrome (IBS), the most common chronic functional gastrointestinal disorder, is categorized as IBS-C and IBS-D, which are equivalent to Ghoolenj Rihi and Maghs Rihi in Iranian traditional medicine. One of the main applications of Zataria multiflora Boiss in traditional medicine is its efficacy in the gastrointestinal tract with symptoms such as IBS. The aim of this study was to evaluate the efficacy of Zataria multiflora essential oil in management of IBS. We used all the accessible references (electronic and published books, theses, and reports) to write this article. The results of our investigation show that the majority of gas chromatography-mass spectrometry (GC-MS) analyses exhibited carvacrol and thymol as the main components of Zataria multiflora essential oil, and 60 drops oral daily dose of Z. multiflora essential oil (2%) can relieve the symptoms of IBS without any adverse effects. The pharmacological studies confirmed the analgesic, anti-inflammatory, antispasm and antiulcer effects of Z. multiflora essential oils and main components. According to the results of studies, oral Z. multiflora essential oil (2%) is a good candidate for management of IBS, but more studies are required to better understand its efficacies.

A novel transcription initiation factor (TIF), TIF-IE, is required for homogeneous Acanthamoeba castellanii TIF-IB (SL1) to form a committed complex.

PubMed

Radebaugh, C A; Kubaska, W M; Hoffman, L H; Stiffler, K; Paule, M R

1998-10-16

The fundamental transcription initiation factor (TIF) for ribosomal RNA expression by eukaryotic RNA polymerase I, TIF-IB, has been purified to near homogeneity from Acanthamoeba castellanii using standard techniques. The purified factor consists of the TATA-binding protein and four TATA-binding protein-associated factors with relative molecular weights of 145,000, 99,000, 96,000, and 91,000. This yields a calculated native molecular weight of 460, 000, which compares well with its mass determined by scanning transmission electron microscopy (493,000) and its sedimentation rate, which is close to RNA polymerase I (515,000). Both impure and nearly homogeneous TIF-IB exhibit an apparent equilibrium dissociation constant of 56 +/- 3 pM. However, although impure TIF-IB can form a promoter-DNA complex resistant to challenge by other promoter-containing DNAs, near homogeneous TIF-IB cannot do so. An additional transcription factor, dubbed TIF-IE, restores the ability of near homogeneous TIF-IB to sequester DNA into a committed complex.

Sensitivity to wheat, gluten and FODMAPs in IBS: facts or fiction?

PubMed

De Giorgio, Roberto; Volta, Umberto; Gibson, Peter R

2016-01-01

IBS is one of the most common types of functional bowel disorder. Increasing attention has been paid to the causative role of food in IBS. Food ingestion precipitates or exacerbates symptoms, such as abdominal pain and bloating in patients with IBS through different hypothesised mechanisms including immune and mast cell activation, mechanoreceptor stimulation and chemosensory activation. Wheat is regarded as one of the most relevant IBS triggers, although which component(s) of this cereal is/are involved remain(s) unknown. Gluten, other wheat proteins, for example, amylase-trypsin inhibitors, and fructans (the latter belonging to fermentable oligo-di-mono-saccharides and polyols (FODMAPs)), have been identified as possible factors for symptom generation/exacerbation. This uncertainty on the true culprit(s) opened a scenario of semantic definitions favoured by the discordant results of double-blind placebo-controlled trials, which have generated various terms ranging from non-coeliac gluten sensitivity to the broader one of non-coeliac wheat or wheat protein sensitivity or, even, FODMAP sensitivity. The role of FODMAPs in eliciting the clinical picture of IBS goes further since these short-chain carbohydrates are found in many other dietary components, including vegetables and fruits. In this review, we assessed current literature in order to unravel whether gluten/wheat/FODMAP sensitivity represent 'facts' and not 'fiction' in IBS symptoms. This knowledge is expected to promote standardisation in dietary strategies (gluten/wheat-free and low FODMAP) as effective measures for the management of IBS symptoms. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Clostridium perfringens Iota-Toxin: Mapping of Receptor Binding and Ia Docking Domains on Ib

PubMed Central

Marvaud, Jean-Christophe; Smith, Theresa; Hale, Martha L.; Popoff, Michel R.; Smith, Leonard A.; Stiles, Bradley G.

2001-01-01

Clostridium perfringens iota-toxin is a binary toxin consisting of iota a (Ia), an ADP-ribosyltransferase that modifies actin, and iota b (Ib), which binds to a cell surface protein and translocates Ia into a target cell. Fusion proteins of recombinant Ib and truncated variants were tested for binding to Vero cells and docking with Ia via fluorescence-activated cytometry and cytotoxicity experiments. C-terminal residues (656 to 665) of Ib were critical for cell surface binding, and truncated Ib variants containing ≥200 amino acids of the C terminus were effective Ib competitors and prevented iota cytotoxicity. The N-terminal domain (residues 1 to 106) of Ib was important for Ia docking, yet this region was not an effective competitor of iota cytotoxicity. Further studies showed that Ib lacking just the N-terminal 27 residues did not facilitate Ia entry into a target cell and subsequent cytotoxicity. Five monoclonal antibodies against Ib were also tested with each truncated Ib variant for epitope and structural mapping by surface plasmon resonance and an enzyme-linked immunosorbent assay. Each antibody bound to a linear epitope within the N terminus (residues 28 to 66) or the C terminus (residues 632 to 655). Antibodies that target the C terminus neutralized in vitro cytotoxicity and delayed the lethal effects of iota-toxin in mice. PMID:11254604

The effect of PDIA3 gene knockout on the mucosal immune function in IBS rats.

PubMed

Zhuang, Zhao-Meng; Wang, Xiao-Teng; Zhang, Lu; Tao, Li-Yuan; Lv, Bin

2015-01-01

To observe the changes of intestinal inflammation on PDIA3 gene knockout IBS rats and its effect on immune function. 36 SD rats were randomly divided into four groups: the control group (n = 8); IBS- empty virus group (IBS-GFP, which); IBS-PDIA3 knockout group (n = 12); IBS- the control group (n = 12). After modeling, colon and ileocecal tissue pathology in each group were observed separately. Changes of immune and inflammatory markers were measured. At the same time, ultrastructural changes in each group were observed by electron microscopy. Compared with the IBS control group, inflammation was reduced significantly in IBS-PDIA3 knockout group. IgE, IL-4 and IL-9 and the level of intestinal trypsin type were decreased significantly. Furthermore, mast cell degranulation and PAR 2 receptor reduced significantly. PDIA3 may play an important role in the development of IBS by mediating through immune responses of mucosal abnormalities. However, the mechanism needs to be confirmed in further study.

MLCK-mediated intestinal permeability promotes immune activation and visceral hypersensitivity in PI-IBS mice.

PubMed

Long, Y; Du, L; Kim, J J; Chen, B; Zhu, Y; Zhang, Y; Yao, S; He, H; Zheng, X; Huang, Z; Dai, N

2018-04-11

Alterations in intestinal permeability regulated by tight junctions (TJs) are associated with immune activation and visceral hypersensitivity in irritable bowel syndrome (IBS). Myosin light chain kinase (MLCK) is an important mediator of epithelial TJ. The aim of this study is to investigate the role of MLCK in the pathogenesis of IBS using a post infectious IBS (PI-IBS) mouse model. Trichinella spiralis-infected PI-IBS mouse model was used. Urine lactulose/mannitol ratio was measured to assess intestinal epithelial permeability. Western blotting was used to evaluate intestinal TJ protein (zonula occludens-1) and MLCK-associated protein expressions. Immune profile was assessed by measuring Th (T helper) 1/Th2 cytokine expression. Visceral sensitivity was determined by abdominal withdrawal reflex in response to colorectal distension. Eight weeks after inoculation with T. spiralis, PI-IBS mice developed decreased pain and volume thresholds during colorectal distention, increased urine lactulose/mannitol ratio, elevated colonic Th1/Th2 cytokine ratio, and decreased zonula occludens-1 expression compared to the control mice. MLCK expression was dramatically elevated in the colonic mucosa of PI-IBS mice compared to the control mice, alongside increased pMLC/MLC and decreased MLCP expression. Administration of MLCK inhibitor and TJ blocker both reversed the increased intestinal permeability, visceral hypersensitivity, and Th1-dominant immune profile in PI-IBS mice. MLCK is a pivotal step in inducing increased intestinal permeability promoting low-grade intestinal immune activation and visceral hypersensitivity in PI-IBS mice. MLCK inhibitor may provide a potential therapeutic option in the treatment of IBS. © 2018 John Wiley & Sons Ltd.

Down-regulation of the IbEXP1 gene enhanced storage root development in sweetpotato

PubMed Central

Bae, Jung Myung

2013-01-01

The role of an expansin gene (IbEXP1) in the formation of the storage root (SR) was investigated by expression pattern analysis and characterization of IbEXP1-antisense sweetpotato (Ipomoea batatas cv. Yulmi) plants in an attempt to elucidate the molecular mechanism underlying SR development in sweetpotato. The transcript level of IbEXP1 was high in the fibrous root (FR) and petiole at the FR stage, but decreased significantly at the young storage root (YSR) stage. IbEXP1-antisense plants cultured in vitro produced FRs which were both thicker and shorter than those of wild-type (WT) plants. Elongation growth of the epidermal cells was significantly reduced, and metaxylem and cambium cell proliferation was markedly enhanced in the FRs of IbEXP1-antisense plants, resulting in an earlier thickening growth in these plants relative to WT plants. There was a marked reduction in the lignification of the central stele of the FRs of the IbEXP1-antisense plants, suggesting that the FRs of the mutant plants possessed a higher potential than those of WT plants to develop into SRs. IbEXP1-antisense plants cultured in soil produced a larger number of SRs and, consequently, total SR weight per IbEXP1-antisense plant was greater than that per WT plant. These results demonstrate that SR development was accelerated in IbEXP1-antisense plants and suggest that IbEXP1 plays a negative role in the formation of SR by suppressing the proliferation of metaxylem and cambium cells to inhibit the initial thickening growth of SRs. IbEXP1 is the first sweetpotato gene whose role in SR development has been directly identified in soil-grown transgenic sweetpotato plants. PMID:22945944

The impact of abuse and mood on bowel symptoms and health-related quality of life in irritable bowel syndrome (IBS).

PubMed

Kanuri, N; Cassell, B; Bruce, S E; White, K S; Gott, B M; Gyawali, C P; Sayuk, G S

2016-10-01

Irritable bowel syndrome (IBS) is a common abdominal pain disorder without an organic explanation. Abuse histories (physical, sexual, emotional) are prevalent in IBS. While abuse relates to mood disorders (depression and anxiety) also common in IBS, the influence of abuse on gastrointestinal (GI) symptoms and health-related quality of life (HRQOL) and its independence from psychological symptom comorbidity has not been studied. Consecutive GI outpatients completed the ROME III Research Diagnostic Questionnaire and questionnaires on trauma (Life-Stress Questionnaire), mood (Beck Depression/Anxiety Inventories), somatic symptoms (PHQ-12), and HRQOL (SF-36). Current GI symptom severity and bother were assessed using 10-cm Visual Analog Scales. 272 ROME-defined IBS (47.6 ± 0.9 years, 81% female) and 246 non-FGID (51.6 ± 1.0 years, 65% female) subjects participated. IBS patients reported greater rates of physical, sexual, and emotional abuse (p < 0.006 each), and higher depression, anxiety, and somatic symptoms (p < 0.001). Greater bowel symptom bother (7.4 ± 0.2 vs 6.7 ± 0.2, p = 0.040), severity (7.7 ± 0.2 vs 6.5 ± 0.2, p < 0.001), recent symptomatic days (9.8 ± 0.4 vs 8.5 ± 0.3, p = 0.02), and poorer HRQOL (40.9 ± 2.3 vs 55.5 ± 1.7, p < 0.001) were noted in IBS with abuse. Abuse effects were additive, with greater IBS symptom severity and poorer HRQOL noted in cases with multiple forms of abuse. Mediation analyses suggested that abuse effects on GI symptoms and HRQOL were partially mediated by mood. Abuse experiences common among IBS sufferers are associated with reports of greater GI symptoms and poorer HRQOL, particularly in those with multiple forms of abuse; this relationship may be partially mediated by concomitant mood disturbances. © 2016 John Wiley & Sons Ltd.

Key factors of successful JIT integration with IBS - An overview

NASA Astrophysics Data System (ADS)

Asri, Mohammad Azwanie Naim Mohammad; Nawi, Mohd Nasrun Mohd; Nadarajan, Santhirasegaran

2016-08-01

The Just-In-Time (JIT) philosophy has been used for many decades to increase productivity through waste elimination process. The purpose of this paper is to contribute to the knowledge by addressing the transportation and material delivery activities in Industrialized Building System (IBS) and integrating JIT to improve the performance of those activities. The literature review has been conducted through relevant database. It was found that there is a need for more holistic approach to be adopted to integrate JIT in IBS project. This paper discusses the key success factors for effective integration between JIT and IBS in the context of transportation and material delivery activities.

Heat transfer in a microvascular network: the effect of heart rate on heating and cooling in reptiles (Pogona barbata and Varanus varius).

PubMed

Seebacher, F

2000-03-21

Thermally-induced changes in heart rate and blood flow in reptiles are believed to be of selective advantage by allowing animal to exert some control over rates of heating and cooling. This notion has become one of the principal paradigms in reptilian thermal physiology. However, the functional significance of changes in heart rate is unclear, because the effect of heart rate and blood flow on total animal heat transfer is not known. I used heat transfer theory to determine the importance of heat transfer by blood flow relative to conduction. I validated theoretical predictions by comparing them with field data from two species of lizard, bearded dragons (Pogona barbata) and lace monitors (Varanus varius). Heart rates measured in free-ranging lizards in the field were significantly higher during heating than during cooling, and heart rates decreased with body mass. Convective heat transfer by blood flow increased with heart rate. Rates of heat transfer by both blood flow and conduction decreased with mass, but the mass scaling exponents were different. Hence, rate of conductive heat transfer decreased more rapidly with increasing mass than did heat transfer by blood flow, so that the relative importance of blood flow in total animal heat transfer increased with mass. The functional significance of changes in heart rate and, hence, rates of heat transfer, in response to heating and cooling in lizards was quantified. For example, by increasing heart rate when entering a heating environment in the morning, and decreasing heart rate when the environment cools in the evening a Pogona can spend up to 44 min longer per day with body temperature within its preferred range. It was concluded that changes in heart rate in response to heating and cooling confer a selective advantage at least on reptiles of mass similar to that of the study animals (0. 21-5.6 kg). Copyright 2000 Academic Press.

IBS and FAPS in children: a comparison of psychological and clinical characteristics.

PubMed

Rutten, Juliette M T M; Benninga, Marc A; Vlieger, Arine M

2014-10-01

It has been suggested that different subcategories of childhood abdominal pain-related functional gastrointestinal disorders (AP-FGIDs) are not separate clinical entities, but represent variable expressions of the same FGID. The aim of the present study was to compare clinical and psychological characteristics of children with irritable bowel syndrome (IBS), functional abdominal pain (FAP), and functional abdominal pain syndrome (FAPS). A total of 259 children, ages 8 to 18 years, fulfilling Rome III criteria for IBS or FAPS were included in a randomized controlled trial evaluating the effect of hypnotherapy. At inclusion, questionnaires assessed demographics, clinical features, abdominal pain frequency and intensity, depression and anxiety, somatization, health-related quality of life, pain beliefs, and coping strategies. No differences were found between children with IBS and those with FAPS with respect to the main outcomes: frequency and intensity of abdominal pain, symptoms of depression and anxiety, somatization, health-related quality of life, pain beliefs, and coping strategies. A significantly higher percentage of patients with IBS had a positive family history for AP-FGIDs (56.8% vs 37.8%; P = 0.00). Characteristics of patients with IBS subtypes did not differ. Patients with FAP or FAPS differed only with respect to problem-focused coping strategy (2.21 ± 0.61 vs 2.52 ± 0.49; P = 0.00). Pediatric patients with IBS and those with FAPS have similar psychosocial profiles. These results may explain why treatment response of psychological therapies in these AP-FGIDs is similar. These results may indicate that pediatric IBS and FAPS are different expressions of 1 underlying functional disorder, but similarities in psychosocial characteristics do not exclude the possibility that these disorders are different entities, because these similarities can exist between disorders of various causes. Therefore, future research is required on the role of other

Phenotyping of subjects for large scale studies on patients with IBS.

PubMed

Boeckxstaens, G E; Drug, V; Dumitrascu, D; Farmer, A D; Hammer, J; Hausken, T; Niesler, B; Pohl, D; Pojskic, L; Polster, A; Simren, M; Goebel-Stengel, M; Van Oudenhove, L; Vassallo, M; Wensaas, K-A; Aziz, Q; Houghton, L A

2016-08-01

Irritable bowel syndrome (IBS) is a complex condition with multiple factors contributing to its aetiology and pathophysiology. Aetiologically these include genetics, life-time events and environment, and physiologically, changes in motility, central processing, visceral sensitivity, immunity, epithelial permeability and gastrointestinal microflora. Such complexity means there is currently no specific reliable biomarker for IBS, and thus IBS continues to be diagnosed and classified according to symptom based criteria, the Rome Criteria. Carefully phenotyping and characterisation of a 'large' pool of IBS patients across Europe and even the world however, might help identify sub-populations with accuracy and consistency. This will not only aid future research but improve tailoring of treatment and health care of IBS patients. The aim of this position paper is to discuss the requirements necessary to standardize the process of selecting and phenotyping IBS patients and how to organise the collection and storage of patient information/samples in such a large multi-centre pan European/global study. We include information on general demographics, gastrointestinal symptom assessment, psychological factors, quality of life, physiological evaluation, genetic/epigenetic and microbiota analysis, biopsy/blood sampling, together with discussion on the organisational, ethical and language issues associated with implementing such a study. The proposed approach and documents selected to be used in such a study was the result of a thoughtful and thorough four-year dialogue amongst experts associated with the European COST action BM1106 GENIEUR (www.GENIEUR.eu). © 2016 John Wiley & Sons Ltd.

The effect of heat transfer mode on heart rate responses and hysteresis during heating and cooling in the estuarine crocodile Crocodylus porosus.

PubMed

Franklin, Craig E; Seebacher, Frank

2003-04-01

The effect of heating and cooling on heart rate in the estuarine crocodile Crocodylus porosus was studied in response to different heat transfer mechanisms and heat loads. Three heating treatments were investigated. C. porosus were: (1) exposed to a radiant heat source under dry conditions; (2) heated via radiant energy while half-submerged in flowing water at 23 degrees C and (3) heated via convective transfer by increasing water temperature from 23 degrees C to 35 degrees C. Cooling was achieved in all treatments by removing the heat source and with C. porosus half-submerged in flowing water at 23 degrees C. In all treatments, the heart rate of C. porosus increased markedly in response to heating and decreased rapidly with the removal of the heat source. Heart rate during heating was significantly faster than during cooling at any given body temperature, i.e. there was a significant heart rate hysteresis. There were two identifiable responses to heating and cooling. During the initial stages of applying or removing the heat source, there was a dramatic increase or decrease in heart rate ('rapid response'), respectively, indicating a possible cardiac reflex. This rapid change in heart rate with only a small change or no change in body temperature (<0.5 degrees C) resulted in Q(10) values greater than 4000, calling into question the usefulness of this measure on heart rate during the initial stages of heating and cooling. In the later phases of heating and cooling, heart rate changed with body temperature, with Q(10) values of 2-3. The magnitude of the heart rate response differed between treatments, with radiant heating during submergence eliciting the smallest response. The heart rate of C. porosus outside of the 'rapid response' periods was found to be a function of the heat load experienced at the animal surface, as well as on the mode of heat transfer. Heart rate increased or decreased rapidly when C. porosus experienced large positive (above 25 W) or negative

The enhancement of stress-related memory by glucocorticoids depends on synapsin-Ia/Ib

PubMed Central

Revest, J-M; Kaouane, N; Mondin, M; Le Roux, A; Rougé-Pont, F; Vallée, M; Barik, J; Tronche, F; Desmedt, A; Piazza, P V

2010-01-01

The activation of glucocorticoid receptors (GR) by glucocorticoids increases stress-related memory through the activation of the MAPK signaling pathway and the downstream transcription factor Egr-1. Here, using converging in vitro and in vivo approaches, respectively, GR-expressing cell lines, culture of hippocampal neurons, and GR genetically modified mice (GRNesCre), we identified synapsin-Ia/Ib as one of the effectors of the glucocorticoid signaling cascade. Stress and glucocorticoid-induced activation of the GR modulate synapsin-Ia/Ib through two complementary mechanisms. First, glucocorticoids driving Egr-1 expression increase the expression of synapsin-Ia/Ib, and second, glucocorticoids driving MAPK activation increase its phosphorylation. Finally, we showed that blocking fucosylation of synapsin-Ia/Ib in the hippocampus inhibits its expression and prevents the glucocorticoid-mediated increase in stress-related memory. In conclusion, our data provide a complete molecular pathway (GR/Egr-1/MAPK/Syn-Ia/Ib) through which stress and glucocorticoids enhance the memory of stress-related events and highlight the function of synapsin-Ia/Ib as molecular effector of the behavioral effects of stress. PMID:20368707

Reports of "satisfactory relief" by IBS patients receiving usual medical care are confounded by baseline symptom severity and do not accurately reflect symptom improvement.

PubMed

Whitehead, William E; Palsson, Olafur S; Levy, Rona L; Feld, Andrew D; VonKorff, Michael; Turner, Marsha

2006-05-01

Treatment trials for irritable bowel syndrome (IBS) usually define a responder as a patient who reports satisfactory relief or adequate relief of symptoms at the end of the trial. However, these measures have not been adequately validated. (1) Compare a binary satisfactory relief measure to alternative ways of defining a treatment responder. (2) Determine whether baseline IBS symptom severity or psychological distress influence the sensitivity of these outcome measures. A total of 350 patients (81% females, average age 50 yr) who had a medical diagnosis of IBS and satisfied Rome II criteria, were recruited from Group Health Cooperative of Puget Sound. At baseline the Irritable Bowel Severity Scale (IBSS) was used to assess symptom severity and to classify patients as mild, moderate, or severe. Psychological distress and IBS-specific quality of life (IBS-QOL) were also assessed. After 6 months treatment with standard medical care, IBSS and IBS-QOL were reassessed, and patients were asked whether they had experienced satisfactory relief and whether they were somewhat or markedly better. Initial severity of IBS significantly affected the proportion who reported satisfactory relief (mild, 72%; moderate, 53%; severe, 44%) and the proportion who were somewhat or markedly better (mild, 62%; moderate, 44%; severe, 38%), but did not affect the proportion with a 50% reduction in symptoms (mild, 26%; moderate, 25%; severe, 23%). Although mild patients were the most likely to report satisfactory relief, they showed no average decrease in symptom severity or improvement in IBS-QOL. Conversely, severe patients, who were the least likely to report satisfactory relief, had the largest reductions in IBS symptom severity and the largest improvements in IBS-QOL. Psychological distress had no significant effect on the responder rate after adjusting for IBS symptom severity. These data from a descriptive study suggest that satisfactory relief is confounded with initial IBS symptom

Digestive state influences the heart rate hysteresis and rates of heat exchange in the varanid lizard Varanus rosenbergi.

PubMed

Clark, T D; Butler, P J; Frappell, P B

2005-06-01

To maximize the period where body temperature (Tb) exceeds ambient temperature (Ta), many reptiles have been reported to regulate heart rate (fH) and peripheral blood flow so that the rate of heat gain in a warming environment occurs more rapidly than the rate of heat loss in a cooling environment. It may be hypothesized that the rate of cooling, particularly at relatively cool Tbs, would be further reduced during postprandial periods when specific dynamic action (SDA) increases endogenous heat production (i.e. the heat increment of feeding). Furthermore, it may also be hypothesized that the increased perfusion of the gastrointestinal organs that occurs during digestion may limit peripheral blood flow and thus compromise the rate of heating. Finally, if the changes in fh are solely for the purpose of thermoregulation, there should be no associated changes in energy demand and, consequently, no hysteresis in the rate of oxygen consumption (V(O2)). To test these hypotheses, seven individual Varanus rosenbergi were heated and cooled between 19 degrees C and 35 degrees C following at least 8 days fasting and then approximately 25 h after consumption of a meal (mean 10% of fasted body mass). For a given Tb between the range of 19-35 degrees C, fh of fasting lizards was higher during heating than during cooling. Postprandial lizards also displayed a hysteresis in fh, although the magnitude was reduced in comparison with that of fasting lizards as a result of a higher fh during cooling in postprandial animals. Both for fasting and postprandial lizards, there was no hysteresis in V(O2) at any Tb throughout the range although, as a result of SDA, postprandial animals displayed a significantly higher V(O2) than fasting animals both during heating and during cooling at Tbs above 24 degrees C. The values of fh during heating at a given Tb were the same for fasting and postprandial animals, which, in combination with a slower rate of heating in postprandial animals, suggests

Nerve growth factor and diarrhea-predominant irritable bowel syndrome (IBS-D): a potential therapeutic target?

PubMed

Xu, Xiao-juan; Liu, Liang; Yao, Shu-kun

2016-01-01

Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder characterized by recurrent abdominal pain or discomfort associated with abnormal bowel habits. Diarrhea-predominant IBS (IBS-D) is a major subtype of IBS, the predominant manifestations of which are abdominal pain and diarrhea. The pathogenesis of IBS-D remained unknown until recently. The effects of psychosocial stress, central hypervigilance, neuroendocrine abnormality, disturbed gastrointestinal motility, mucosal immune activation, intestinal barrier dysfunction, visceral hypersensitivity (VH), altered gut flora, and genetic susceptibility may be involved in its development. Recently, increased attention has been placed on the neural-immune-endocrine network mechanism in IBS-D, especially the role of various neuroendocrine mediators. As a member of the neurotrophin family, nerve growth factor (NGF) has diverse biological effects, and participates in the pathogenesis of many diseases. Basic studies have demonstrated that NGF is associated with inflammatory- and stress-related VH, as well as stress-related intestinal barrier dysfunction. The aim of this study is to summarize recent literature and discuss the role of NGF in the pathophysiology of IBS-D, especially in VH and intestinal barrier dysfunction, as well as its potential as a therapeutic target in IBS-D.

Chronic Constipation and Constipation-Predominant IBS: Separate and Distinct Disorders or a Spectrum of Disease?

PubMed

Siah, Kewin T H; Wong, Reuben K; Whitehead, William E

2016-03-01

Rome III diagnostic criteria separate patients with idiopathic chronic constipation into mutually exclusive categories of constipation-predominant irritable bowel syndrome (IBS-C) or functional constipation (FC). However, several experts think that these conditions are not different disorders, but parts of a continuum. To shed light on this issue, we examined studies that compared IBS-C with FC with respect to symptoms, pathophysiologic mechanisms, and treatment response. When the Rome III requirement that patients meeting criteria for IBS cannot also be given a diagnosis of FC is suspended, most patients meet criteria for both, and, contrary to expectation, IBS-C patients have more symptoms of constipation than patients with FC. No symptoms reliably separate IBS-C from FC. Physiologic tests are not reliably associated with diagnosis, but visceral pain hypersensitivity tends to be more strongly associated with IBS-C than with FC, and delayed colonic transit tends to be more common in FC. Although some treatments are effective for both IBS-C and FC, such as prosecretory agents, other treatments are specific to IBS-C (eg, antidepressants, antispasmodics, cognitive behavior therapy) or FC (eg, prucalopride, biofeedback). Future studies should permit IBS-C and FC diagnoses to overlap. Physiologic tests comparing these disorders should include visceral pain sensitivity, colonic transit time, time to evacuate a water-filled balloon, and anal pressures or electromyographic activity from the anal canal. To date, differential responses to treatment provide the strongest evidence that IBS-C and FC may be different disorders, rather than parts of a spectrum.

Chronic Constipation and Constipation-Predominant IBS: Separate and Distinct Disorders or a Spectrum of Disease?

PubMed Central

Siah, Kewin T. H.; Wong, Reuben K.

2016-01-01

Rome III diagnostic criteria separate patients with idiopathic chronic constipation into mutually exclusive categories of constipation-predominant irritable bowel syndrome (IBS-C) or functional constipation (FC). However, several experts think that these conditions are not different disorders, but parts of a continuum. To shed light on this issue, we examined studies that compared IBS-C with FC with respect to symptoms, pathophysiologic mechanisms, and treatment response. When the Rome III requirement that patients meeting criteria for IBS cannot also be given a diagnosis of FC is suspended, most patients meet criteria for both, and, contrary to expectation, IBS-C patients have more symptoms of constipation than patients with FC. No symptoms reliably separate IBS-C from FC. Physiologic tests are not reliably associated with diagnosis, but visceral pain hypersensitivity tends to be more strongly associated with IBS-C than with FC, and delayed colonic transit tends to be more common in FC. Although some treatments are effective for both IBS-C and FC, such as prosecretory agents, other treatments are specific to IBS-C (eg, antidepressants, antispasmodics, cognitive behavior therapy) or FC (eg, prucalopride, biofeedback). Future studies should permit IBS-C and FC diagnoses to overlap. Physiologic tests comparing these disorders should include visceral pain sensitivity, colonic transit time, time to evacuate a water-filled balloon, and anal pressures or electromyographic activity from the anal canal. To date, differential responses to treatment provide the strongest evidence that IBS-C and FC may be different disorders, rather than parts of a spectrum. PMID:27231446

IB Offering Certificate for Careers

ERIC Educational Resources Information Center

Robelen, Erik W.

2012-01-01

The International Baccalaureate (IB) organization, best known in the United States for its prestigious two-year diploma program for juniors and seniors, will enter new terrain this fall as it formally rolls out an initiative centered on a variety of career pathways that includes engineering, culinary arts, and automotive technology. The move comes…

Induction by TNF-α of IL-6 and IL-8 in cystic fibrosis bronchial IB3-1 epithelial cells encapsulated in alginate microbeads.

PubMed

Borgatti, Monica; Mazzitelli, Stefania; Breveglieri, Giulia; Gambari, Roberto; Nastruzzi, Claudio

2010-01-01

We have developed a microencapsulation procedure for the entrapment and manipulation of IB3-1 cystic fibrosis cells. The applied method is based on generation of monodisperse droplets by a vibrational nozzle. Different experimental parameters were analyzed, including frequency and amplitude of vibration, polymer pumping rate and distance between the nozzle and the gelling bath. We have found that the microencapsulation procedure does not alter the viability of the encapsulated IB3-1 cells. The encapsulated IB3-1 cells were characterized in term of secretomic profile, analyzing the culture medium by Bio-Plex strategy. The experiments demonstrated that most of the analyzed proteins, were secreted both by the free and encapsulated cells, even if in a different extent. In order to determine the biotechnological applications of this procedure, we determined whether encapsulated IB3-1 cells could be induced to pro-inflammatory responses, after treatment with TNF-α. In this experimental set-up, encapsulated and free IB3-1 cells were treated with TNF-α, thereafter the culture media from both cell populations were collected. As expected, TNF-α induced a sharp increase in the secretion of interleukins, chemokines and growth factors. Of great interest was the evidence that induction of interleukin-6 and interleukin-8 occurs also by encapsulated IB3-1 cells.

A simple parameterization for the height of maximum ozone heating rate

NASA Astrophysics Data System (ADS)

Zhang, Feng; Hou, Can; Li, Jiangnan; Liu, Renqiang; Liu, Cuiping

2017-12-01

It is well-known that the height of the maximum ozone heating rate is much higher than the height of the maximum ozone concentration in the stratosphere. However, it lacks an analytical expression to explain it. A simple theoretical model has been proposed to calculate the height of maximum ozone heating rate and further understand this phenomenon. Strong absorption of ozone causes the incoming solar flux to be largely attenuated before reaching the location of the maximum ozone concentration. By comparing with the exact radiative transfer calculations, the heights of the maximum ozone heating rate produced by the theoretical model are generally very close to the true values. When the cosine of solar zenith angle μ0 = 1.0 , in US Standard atmosphere, the heights of the maximum ozone heating rate by the theoretical model are 41.4 km in the band 0.204-0.233 μm, 47.9 km in the band 0.233-0.270 μm, 44.5 km in the band 0.270-0.286 μm, 37.1 km in the band 0.286-0.303 μm, and 30.2 km in the band 0.303-0.323 μm, respectively. The location of the maximum ozone heating rate is sensitive to the solar spectral range. In band 1, the heights of the maximum ozone heating rate by the theoretical model are 52.3 km for μ0 = 0.1 , 47.1 km for μ0 = 0.3 , 44.6 km for μ0 = 0.5 , 43.1 km for μ0 = 0.7 , 41.9 km for μ0 = 0.9 , 41.4 km for μ0 = 1.0 in US Standard atmosphere, respectively. This model also illustrates that the location of the maximum ozone heating rate is sensitive to the solar zenith angle.

Coal-Fired Power Plant Heat Rate Reductions

EPA Pesticide Factsheets

View a report that identifies systems and equipment in coal-fired power plants where efficiency improvements can be realized, and provides estimates of the resulting net plant heat rate reductions and costs for implementation.

Sparing Bilateral Neck Level IB in Oropharyngeal Carcinoma and Xerostomia Outcomes

PubMed Central

Tam, Moses; Riaz, Nadeem; Kannarunimit, Danita; Peña, Angela P.; Schupak, Karen D.; Gelblum, Daphna Y.; Wolden, Suzanne L.; Rao, Shyam; Lee, Nancy Y.

2017-01-01

Objectives To assess whether sparing neck level IB in target delineation of node positive (N+) oropharyngeal carcinoma (OPC) can improve xerostomia outcomes without compromising local-regional control (LRC). Methods 125 N+ OPC patients with a median age of 57 years underwent chemoradiation between 5/10 and 12/11. 74% of patients had T1-2 disease, 26% T3-4, 16% N1, 8% N2A, 48% N2B, 28% N2C; 53% base of tongue, 41% tonsil, and 6% other. Patients were divided into those who had target delineation sparing of bilateral level IB (the spared cohort) vs. no sparing (the treated cohort). Sparing of contralateral high level II nodes was also performed more consistently in the spared cohort. A prospective xerostomia questionnaire (patient reported) was given at each patient follow-up visit to this cohort of patients to assess late xerostomia. Clinical assessment (observer rated) at each patient follow-up visit was also recorded. Results The 2-year LRC for the spared and treated cohorts was 97.5% and 93.8%, respectively (median follow-up, 23.2 months). No local-regional failures occurred outside of treatment fields. The spared cohort experienced significant benefits in patient-reported xerostomia summary scores (P = 0.021) and observer-rated xerostomia scores (P = 0.006). In addition, there were significant reductions in mean doses to the ipsilateral submandibular gland (SMG; 63.9 Gy vs. 70.5 Gy; P < 0.001), contralateral SMG (45.0 Gy vs. 56.2 Gy; P < 0.001), oral cavity (35.9 Gy vs. 45.2 Gy; P < 0.001), and contralateral parotid gland (20.0 Gy vs. 24.4 Gy; P < 0.001). Conclusions Target delineation sparing of bilateral level IB nodes in N+ OPC reduced mean doses to salivary organs without compromising LRC. Patients with reduced target volumes had better patient-reported xerostomia outcomes. PMID:26208401

IBS: an illustrator for the presentation and visualization of biological sequences.

PubMed

Liu, Wenzhong; Xie, Yubin; Ma, Jiyong; Luo, Xiaotong; Nie, Peng; Zuo, Zhixiang; Lahrmann, Urs; Zhao, Qi; Zheng, Yueyuan; Zhao, Yong; Xue, Yu; Ren, Jian

2015-10-15

Biological sequence diagrams are fundamental for visualizing various functional elements in protein or nucleotide sequences that enable a summarization and presentation of existing information as well as means of intuitive new discoveries. Here, we present a software package called illustrator of biological sequences (IBS) that can be used for representing the organization of either protein or nucleotide sequences in a convenient, efficient and precise manner. Multiple options are provided in IBS, and biological sequences can be manipulated, recolored or rescaled in a user-defined mode. Also, the final representational artwork can be directly exported into a publication-quality figure. The standalone package of IBS was implemented in JAVA, while the online service was implemented in HTML5 and JavaScript. Both the standalone package and online service are freely available at http://ibs.biocuckoo.org. renjian.sysu@gmail.com or xueyu@hust.edu.cn Supplementary data are available at Bioinformatics online. © The Author 2015. Published by Oxford University Press.

IBS: an illustrator for the presentation and visualization of biological sequences

PubMed Central

Liu, Wenzhong; Xie, Yubin; Ma, Jiyong; Luo, Xiaotong; Nie, Peng; Zuo, Zhixiang; Lahrmann, Urs; Zhao, Qi; Zheng, Yueyuan; Zhao, Yong; Xue, Yu; Ren, Jian

2015-01-01

Summary: Biological sequence diagrams are fundamental for visualizing various functional elements in protein or nucleotide sequences that enable a summarization and presentation of existing information as well as means of intuitive new discoveries. Here, we present a software package called illustrator of biological sequences (IBS) that can be used for representing the organization of either protein or nucleotide sequences in a convenient, efficient and precise manner. Multiple options are provided in IBS, and biological sequences can be manipulated, recolored or rescaled in a user-defined mode. Also, the final representational artwork can be directly exported into a publication-quality figure. Availability and implementation: The standalone package of IBS was implemented in JAVA, while the online service was implemented in HTML5 and JavaScript. Both the standalone package and online service are freely available at http://ibs.biocuckoo.org. Contact: renjian.sysu@gmail.com or xueyu@hust.edu.cn Supplementary information: Supplementary data are available at Bioinformatics online. PMID:26069263

Heating rate effects in simulated liquid Al2O_3

NASA Astrophysics Data System (ADS)

van Hoang, Vo

2006-01-01

The heating rate effects in simulated liquid Al{2}O{3} have been investigated by Molecular Dynamics (MD) method. Simulations were done in the basic cube under periodic boundary conditions containing 3000 ions with Born-Mayer type pair potentials. The temperature of the system was increasing linearly in time from the zero temperature as T(t)=T0 +γ t, where γ is the heating rate. The heating rate dependence of density and enthalpy of the system was found. Calculations show that static properties of the system such as the coordination number distributions and bond-angle distributions slightly depend on γ . Structure of simulated amorphous Al{2}O{3} model with the real density at the ambient pressure is in good agreement with Lamparter's experimental data. The heating rate dependence of dynamics of the system has been studied through the diffusion constant, mean-squared atomic displacement and comparison of partial radial distribution functions (PRDFs) for 10% most mobile and immobile particles with the corresponding mean ones. Finally, the evolution of diffusion constant of Al and O particles and structure of the system upon heating for the smallest heating rate was studied and presented. And we find that the temperature dependence of self-diffusion constant in the high temperature region shows a crossover to one which can be described well by a power law, D∝ (T-Tc )^γ . The critical temperature Tc is about 3500 K and the exponent γ is close to 0.941 for Al and to 0.925 for O particles. The glass phase transition temperature Tg for the Al{2}O{3} system is at anywhere around 2000 K.

40 CFR 75.36 - Missing data procedures for heat input rate determinations.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 16 2011-07-01 2011-07-01 false Missing data procedures for heat input... (CONTINUED) AIR PROGRAMS (CONTINUED) CONTINUOUS EMISSION MONITORING Missing Data Substitution Procedures § 75.36 Missing data procedures for heat input rate determinations. (a) When hourly heat input rate is...

40 CFR 75.36 - Missing data procedures for heat input rate determinations.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 17 2014-07-01 2014-07-01 false Missing data procedures for heat input... (CONTINUED) AIR PROGRAMS (CONTINUED) CONTINUOUS EMISSION MONITORING Missing Data Substitution Procedures § 75.36 Missing data procedures for heat input rate determinations. (a) When hourly heat input rate is...

40 CFR 75.36 - Missing data procedures for heat input rate determinations.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 17 2013-07-01 2013-07-01 false Missing data procedures for heat input... (CONTINUED) AIR PROGRAMS (CONTINUED) CONTINUOUS EMISSION MONITORING Missing Data Substitution Procedures § 75.36 Missing data procedures for heat input rate determinations. (a) When hourly heat input rate is...

40 CFR 75.36 - Missing data procedures for heat input rate determinations.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Missing data procedures for heat input... (CONTINUED) AIR PROGRAMS (CONTINUED) CONTINUOUS EMISSION MONITORING Missing Data Substitution Procedures § 75.36 Missing data procedures for heat input rate determinations. (a) When hourly heat input rate is...

40 CFR 75.36 - Missing data procedures for heat input rate determinations.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 17 2012-07-01 2012-07-01 false Missing data procedures for heat input... (CONTINUED) AIR PROGRAMS (CONTINUED) CONTINUOUS EMISSION MONITORING Missing Data Substitution Procedures § 75.36 Missing data procedures for heat input rate determinations. (a) When hourly heat input rate is...

Tight junctions and IBS--the link between epithelial permeability, low-grade inflammation, and symptom generation?

PubMed

Piche, T

2014-03-01

In this issue of Neurogastroenterology and Motility, Dr Ewa Wilcz-Villega and colleagues report low expression of E-cadherin, a tight junction protein involved in the regulation of paracellular permeability, in the colonic mucosa of patients with the irritable bowel syndrome (IBS) with predominance of diarrhea (IBS-D) or alternating symptoms (IBS-A). These findings constitute an improvement in our knowledge of epithelial barrier disruption associated with IBS. There is mounting evidence to indicate that a compromised epithelial barrier is associated with low-grade immune activation and intestinal dysfunction in at least a proportion of IBS patients. During the last 10 years of research, much interest has focused on the increase in the number of different types of immune cells in the gut mucosa of IBS patients including: mast cells, T lymphocytes, and other local cells such as enteroendocrine cells. The inflammatory mediators released by these cells or other luminal factors could be at the origin of altered epithelial barrier functions and enteric nervous system signaling, which lead to gut hypersensitivity. A current conceptual framework states that clinical symptoms of IBS could be associated with structural and functional abnormalities of the mucosal barrier, highlighting the crucial importance of elucidating the contributory role of epithelial barrier defects in the pathogenesis of IBS. More importantly, disruption of the epithelial barrier could also participate in the generation of persistent abdominal pain and discomfort mimicking IBS in patients with inflammatory bowel diseases considered in remission. This mini review gives a brief summary of clinical and experimental evidence concerning the mechanisms underlying epithelial barrier defects in IBS. © 2014 John Wiley & Sons Ltd.

Laser heating and ablation at high repetition rate in thermal confinement regime

NASA Astrophysics Data System (ADS)

Brygo, François; Semerok, A.; Oltra, R.; Weulersse, J.-M.; Fomichev, S.

2006-09-01

Laser heating and ablation of materials with low absorption and thermal conductivity (paint and cement) were under experimental and theoretical investigations. The experiments were made with a high repetition rate Q-switched Nd:YAG laser (10 kHz, 90 ns pulse duration and λ = 532 nm). High repetition rate laser heating resulted in pulse per pulse heat accumulation. A theoretical model of laser heating was developed and demonstrated a good agreement between the experimental temperatures measured with the infrared pyrometer and the calculated ones. With the fixed wavelength and laser pulse duration, the ablation threshold fluence of paint was found to depend on the repetition rate and the number of applied pulses. With a high repetition rate, the threshold fluence decreased significantly when the number of applied pulses was increasing. The experimentally obtained thresholds were well described by the developed theoretical model. Some specific features of paint heating and ablation with high repetition rate lasers are discussed.

Evaluation of the Irritable Bowel Syndrome Quality of Life (IBS-QOL) questionnaire in diarrheal-predominant irritable bowel syndrome patients

PubMed Central

2013-01-01

Background Diarrhea-predominant irritable bowel syndrome (IBS-d) significantly diminishes the health-related quality of life (HRQOL) of patients. Psychological and social impacts are common with many IBS-d patients reporting comorbid depression, anxiety, decreased intimacy, and lost working days. The Irritable Bowel Syndrome Quality of Life (IBS-QOL) questionnaire is a 34-item instrument developed and validated for measurement of HRQOL in non-subtyped IBS patients. The current paper assesses this previously-validated instrument employing data collected from 754 patients who participated in a randomized clinical trial of a novel treatment, eluxadoline, for IBS-d. Methods Psychometric methods common to HRQOL research were employed to evaluate the IBS-QOL. Many of the historical analyses of the IBS-QOL validations were used. Other techniques that extended the original methods were applied where more appropriate for the current dataset. In IBS-d patients, we analyzed the items and substructure of the IBS-QOL via item reduction, factor structure, internal consistency, reproducibility, construct validity, and ability to detect change. Results This study supports the IBS-QOL as a psychometrically valid measure. Factor analyses suggested that IBS-specific QOL as measured by the IBS-QOL is a unidimensional construct. Construct validity was further buttressed by significant correlations between IBS-QOL total scores and related measures of IBS-d severity including the historically-relevant Irritable Bowel Syndrome Adequate Relief (IBS-AR) item and the FDA’s Clinical Responder definition. The IBS-QOL also showed a significant ability to detect change as evidenced by analysis of treatment effects. A minority of the items, unrelated to the IBS-d, performed less well by the standards set by the original authors. Conclusions We established that the IBS-QOL total score is a psychometrically valid measure of HRQOL in IBS-d patients enrolled in this study. Our analyses suggest that

Charring rate of wood exposed to a constant heat flux

Treesearch

R. H. White; H. C. Tran

1996-01-01

A critical factor in the fire endurance of a wood member is its rate of charring. Most available charring rate data have been obtained using the time-temperature curves of the standard fire resistance tests (ASTM E 119 and ISO 834) to define the fire exposure. The increased use of heat release calorimeters using exposures of constant heat flux levels has broadened the...

Fecal incontinence in irritable bowel syndrome (IBS): Prevalence and associated factors in Swedish and American patients

PubMed Central

Simrén, Magnus; Palsson, Olafur S.; Heymen, Steve; Bajor, Antal; Törnblom, Hans; Whitehead, William E.

2016-01-01

Background Fecal incontinence (FI) is a prevalent but poorly recognized problem in the general population with profound negative effects on daily life. The prevalence of FI in IBS and its association with clinical, demographic and pathophysiological factors are largely unknown. Methods One US (n=304) and one Swedish (n=168) patient cohort fulfilling Rome III criteria for IBS completed Rome III diagnostic questions on FI and IBS symptoms, and questionnaires on IBS symptom severity, quality of life, anxiety and depression, and work productivity impairment. The patients also underwent assessments of colorectal sensitivity and motility. Key Results FI ≥ one day per month was reported by 19.7% (USA) and 13.7% (Sweden) of IBS patients. These proportions rose to 43.4% and 29.8% if patients with less frequent FI were included. FI prevalence was higher in older age groups, with a clear increase above age 40. IBS patients with FI reported greater overall IBS symptom severity, more frequent and loose stools, and greater urgency. Negative effects of FI on quality of life, psychological distress, and work productivity were demonstrated. No associations were found between colorectal physiology and FI. Conclusions & Inferences FI is common in IBS patients, and similar to previous general population reports, the major risk factors for FI in IBS are older age, rectal urgency, and loose, frequent stools. When IBS patients have comorbid FI, the impact on quality of life, psychological symptoms, and work impairment appears greater. PMID:27581702

Growth hormone deficiency in monozygotic twins with autosomal dominant pseudohypoparathyroidism type Ib.

PubMed

Sano, Shinichiro; Iwata, Hiromi; Matsubara, Keiko; Fukami, Maki; Kagami, Masayo; Ogata, Tsutomu

2015-01-01

Pseudohypoparathyroidism (PHP) is associated with compromised signal transductions via PTH receptor (PTH-R) and other G-protein-coupled receptors including GHRH-R. To date, while GH deficiency (GHD) has been reported in multiple patients with PHP-Ia caused by mutations on the maternally expressed GNAS coding regions and in two patients with sporadic form of PHP-Ib accompanied by broad methylation defects of maternally derived GNAS differentially methylated regions (DMRs), it has not been identified in a patient with an autosomal dominant form of PHP-Ib (AD-PHP-Ib) accompanied by an STX16 microdeletion and an isolated loss of methylation (LOM) at exon A/B-DMR. We studied 5 4/12-year-old monozygotic twins with short stature (both -3.4 SD) and GHD (peak GH values, <6.0 μg/L after arginine and clonidine stimulations). Molecular studies revealed maternally derived STX16 microdeletions and isolated LOMs at exon A/B-DMR in the twins, confirming the diagnosis of AD-PHP-Ib. GNAS mutation was not identified, and neither mutation nor copy number variation was detected in GH1, POU1F1, PROP1, GHRHR, LHX3, LHX4, and HESX1 in the twins. The results, in conjunction with the previous finding that GNAS shows maternal expression in the pituitary, suggest that GHD of the twins is primarily ascribed to compromised GHRH-R signaling caused by AD-PTH-Ib. Thus, resistance to multiple hormones including GHRH should be considered in AD-PHP-Ib.

A double-blind, placebo-controlled study to assess the effect of a probiotic mixture on symptoms and inflammatory markers in women with diarrhea-predominant IBS.

PubMed

Hod, K; Sperber, A D; Ron, Y; Boaz, M; Dickman, R; Berliner, S; Halpern, Z; Maharshak, N; Dekel, R

2017-07-01

Micro-inflammation is considered an element in the pathogenesis of irritable bowel syndrome (IBS). High-sensitivity C reactive protein (hs-CRP) was previously shown to be higher in IBS compared to healthy controls, albeit within the normal range. Since probiotics may suppress micro-inflammation in the gut, we tested if they reduce symptoms and inflammatory markers (hs-CRP and fecal calprotectin (FC) in diarrhea-predominant IBS (IBS-D). The aim of this study was to assess the clinical and laboratory effects of BIO-25, a multispecies probiotic, in women with IBS-D. A double-blind, placebo-controlled study. Following a 2-week run-in, eligible women were assigned at random to a probiotic capsule or an indistinguishable placebo, twice daily for 8 weeks. IBS symptoms and stool consistency were rated daily by Visual Analogue Scales (VAS) and the Bristol Stool Scale (BSS). High-sensitivity C reactive protein was tested at baseline, 4 and 8 weeks. FC was tested at baseline and 8 weeks. One hundred and seventy-two IBS-D patients were recruited and 107 eligible patients were allocated to the intervention (n=54) or placebo (n=53) group. All symptoms improved in both groups with no significant difference between them in symptom improvement, hs-CRP or FC levels. An 8-week treatment with BIO-25 improved symptoms in women with IBS-D, but was not superior to placebo. This rigorously designed and executed study supports the findings of other studies that did not demonstrate superiority of probiotics over placebo in IBS. High quality clinical studies are necessary to examine the efficacy of other specific probiotics in IBS-D patients since data are still conflicting. © 2017 John Wiley & Sons Ltd.

Adhesive properties of the isolated amino-terminal domain of platelet glycoprotein Ibα in a flow field

PubMed Central

Marchese, Patrizia; Saldívar, Enrique; Ware, Jerry; Ruggeri, Zaverio M.

1999-01-01

We have examined the interaction between the amino-terminal domain of platelet glycoprotein (GP) Ibα and immobilized von Willebrand Factor (vWF) under flow conditions in the absence of other components of the GP Ib–IX–V complex. Latex beads were coated with a recombinant fragment containing GP Ibα residues 1–302, either with normal sequence or with the single G233V substitution that causes enhanced affinity for plasma vWF in platelet-type pseudo-von-Willebrand disease. Beads coated with native fragment adhered to vWF in a manner comparable to platelets, showing surface translocation that reflected the transient nature of the bonds formed. Thus, the GP Ibα extracellular domain is necessary and sufficient for interacting with vWF under high shear stress. Beads coated with the mutated fragment became tethered to vWF in greater number and had lower velocity of translocation than beads coated with the normal counterpart, suggesting that the G233V mutation lowers the rate of bond dissociation. Our findings define an approach for studying the biomechanical properties of the GP Ibα–vWF bond and suggest that this interaction is tightly regulated to allow rapid binding at sites of vascular injury, while permitting the concurrent presence of receptor and ligand in the circulation. PMID:10393908

40 CFR 75.83 - Calculation of Hg mass emissions and heat input rate.

Code of Federal Regulations, 2010 CFR

2010-07-01

... heat input rate. 75.83 Section 75.83 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Calculation of Hg mass emissions and heat input rate. The owner or operator shall calculate Hg mass emissions and heat input rate in accordance with the procedures in sections 9.1 through 9.3 of appendix F to...

Characterization of IBS-like symptoms in patients with ulcerative colitis in clinical remission.

PubMed

Jonefjäll, B; Strid, H; Ohman, L; Svedlund, J; Bergstedt, A; Simren, M

2013-09-01

Gastrointestinal symptoms compatible with Irritable Bowel Syndrome (IBS) are common in patients with inflammatory bowel disease. It has been suggested that these symptoms are a reflection of occult inflammation rather than coexisting IBS. The aim of this study was to characterize IBS-like symptoms in patients with Ulcerative Colitis (UC) in clinical remission by assessing inflammatory markers, psychological symptoms, and quality of life. Ninety-four patients with new onset of UC were followed prospectively during 3 years with yearly follow-up visits. The patients completed self-administrated questionnaires. Fecal calprotectin was used as an inflammatory biomarker. Remission was defined as a total Mayo-score ≤2 and an endoscopic subscore ≤1, with no relapse during the 3-month period prior to visit. The prevalence of patients that fulfilled Rome II criteria for IBS among UC patients in remission was 11% at visit 1, 23% at visit 2, and 17% at visit 3. When comparing UC patients in remission with and without IBS-like symptom, patients with IBS-like symptoms had more severe gastrointestinal symptoms, tendencies toward more severe psychological symptoms and reduced levels of quality of life, but the calprotectin levels did not differ between the two groups. IBS-like symptoms are common in patients with UC in clinical remission and these fluctuate over time. The symptoms are associated with poor psychological well-being and reduced quality of life, and do not seem to be a reflection of low-grade inflammatory activity. © 2013 John Wiley & Sons Ltd.

Can reptile embryos influence their own rates of heating and cooling?

PubMed

Du, Wei-Guo; Tu, Ming-Chung; Radder, Rajkumar S; Shine, Richard

2013-01-01

Previous investigations have assumed that embryos lack the capacity of physiological thermoregulation until they are large enough for their own metabolic heat production to influence nest temperatures. Contrary to intuition, reptile embryos may be capable of physiological thermoregulation. In our experiments, egg-sized objects (dead or infertile eggs, water-filled balloons, glass jars) cooled down more rapidly than they heated up, whereas live snake eggs heated more rapidly than they cooled. In a nest with diel thermal fluctuations, that hysteresis could increase the embryo's effective incubation temperature. The mechanisms for controlling rates of thermal exchange are unclear, but may involve facultative adjustment of blood flow. Heart rates of snake embryos were higher during cooling than during heating, the opposite pattern to that seen in adult reptiles. Our data challenge the view of reptile eggs as thermally passive, and suggest that embryos of reptile species with large eggs can influence their own rates of heating and cooling.

Can Reptile Embryos Influence Their Own Rates of Heating and Cooling?

PubMed Central

Du, Wei-Guo; Tu, Ming-Chung; Shine, Richard

2013-01-01

Previous investigations have assumed that embryos lack the capacity of physiological thermoregulation until they are large enough for their own metabolic heat production to influence nest temperatures. Contrary to intuition, reptile embryos may be capable of physiological thermoregulation. In our experiments, egg-sized objects (dead or infertile eggs, water-filled balloons, glass jars) cooled down more rapidly than they heated up, whereas live snake eggs heated more rapidly than they cooled. In a nest with diel thermal fluctuations, that hysteresis could increase the embryo’s effective incubation temperature. The mechanisms for controlling rates of thermal exchange are unclear, but may involve facultative adjustment of blood flow. Heart rates of snake embryos were higher during cooling than during heating, the opposite pattern to that seen in adult reptiles. Our data challenge the view of reptile eggs as thermally passive, and suggest that embryos of reptile species with large eggs can influence their own rates of heating and cooling. PMID:23826200

Increased production of BDNF in colonic epithelial cells induced by fecal supernatants from diarrheic IBS patients.

PubMed

Wang, Peng; Chen, Fei-Xue; Du, Chao; Li, Chang-Qing; Yu, Yan-Bo; Zuo, Xiu-Li; Li, Yan-Qing

2015-05-22

Colonic brain-derived neurotrophic factor (BDNF) plays an essential role in pathogenesis of abdominal pain in diarrhea-predominant irritable bowel syndrome (IBS-D), but regulation on its expression remains unclear. We investigated the role of fecal supernatants (FSN) from IBS-D patients on regulating BDNF expression in colonic epithelial cells of human and mice. Using human Caco-2 cells, we found that IBS-D FSN significantly increased BDNF mRNA and protein levels compared to control FSN, which were remarkably suppressed by the serine protease inhibitor. To further explore the potential mechanisms, we investigated the impact of protease-activated receptor-2 (PAR-2) on BDNF expression. We found a significant increase in PAR-2 expression in Caco-2 after IBS-D FSN stimulation. Knockdown of PAR-2 significantly inhibited IBS-D FSN-induced upregulation of BDNF. Moreover, we found that phosphorylation of p38 MAPK, not NF-κB p65, contributed to PAR-2-mediated BDNF overexpression. To confirm these results, we intracolonically infused IBS-D or control FSN in mice and found that IBS-D FSN significantly elevated colonic BDNF and visceral hypersensitivity in mice, which were both suppressed by the inhibitor of serine protease or antagonist of PAR-2. Together, our data indicate that activation of PAR-2 signaling by IBS-D FSN promotes expression of colonic BDNF, thereby contributing to IBS-like visceral hypersensitivity.

Dissolution and Precipitation Behaviour during Continuous Heating of Al–Mg–Si Alloys in a Wide Range of Heating Rates

PubMed Central

Osten, Julia; Milkereit, Benjamin; Schick, Christoph; Kessler, Olaf

2015-01-01

In the present study, the dissolution and precipitation behaviour of four different aluminium alloys (EN AW-6005A, EN AW-6082, EN AW-6016, and EN AW-6181) in four different initial heat treatment conditions (T4, T6, overaged, and soft annealed) was investigated during heating in a wide dynamic range. Differential scanning calorimetry (DSC) was used to record heating curves between 20 and 600 °C. Heating rates were studied from 0.01 K/s to 5 K/s. We paid particular attention to control baseline stability, generating flat baselines and allowing accurate quantitative evaluation of the resulting DSC curves. As the heating rate increases, the individual dissolution and precipitation reactions shift to higher temperatures. The reactions during heating are significantly superimposed and partially run simultaneously. In addition, precipitation and dissolution reactions are increasingly suppressed as the heating rate increases, whereby exothermic precipitation reactions are suppressed earlier than endothermic dissolution reactions. Integrating the heating curves allowed the enthalpy levels of the different initial microstructural conditions to be quantified. Referring to time–temperature–austenitisation diagrams for steels, continuous heating dissolution diagrams for aluminium alloys were constructed to summarise the results in graphical form. These diagrams may support process optimisation in heat treatment shops.

Cloud Properties and Radiative Heating Rates for TWP

DOE Data Explorer

Comstock, Jennifer

2013-11-07

A cloud properties and radiative heating rates dataset is presented where cloud properties retrieved using lidar and radar observations are input into a radiative transfer model to compute radiative fluxes and heating rates at three ARM sites located in the Tropical Western Pacific (TWP) region. The cloud properties retrieval is a conditional retrieval that applies various retrieval techniques depending on the available data, that is if lidar, radar or both instruments detect cloud. This Combined Remote Sensor Retrieval Algorithm (CombRet) produces vertical profiles of liquid or ice water content (LWC or IWC), droplet effective radius (re), ice crystal generalized effective size (Dge), cloud phase, and cloud boundaries. The algorithm was compared with 3 other independent algorithms to help estimate the uncertainty in the cloud properties, fluxes, and heating rates (Comstock et al. 2013). The dataset is provided at 2 min temporal and 90 m vertical resolution. The current dataset is applied to time periods when the MMCR (Millimeter Cloud Radar) version of the ARSCL (Active Remotely-Sensed Cloud Locations) Value Added Product (VAP) is available. The MERGESONDE VAP is utilized where temperature and humidity profiles are required. Future additions to this dataset will utilize the new KAZR instrument and its associated VAPs.

Immersed boundary peridynamics (IB/PD) method to simulate aortic dissection

NASA Astrophysics Data System (ADS)

Bhalla, Amneet Pal Singh; Griffith, Boyce

2016-11-01

Aortic dissection occurs when an intimal tear in the aortic wall propagates into the media to form a false lumen within the vessel wall. Rupture of the false lumen and collapse of the true lumen both carry a high risk of morbidity and mortality. Surgical treatment consists of either replacement of a portion of the aorta, or stent implantation to cover the affected segment. Both approaches carry significant risks: open surgical intervention is highly invasive, whereas stents can be challenging to implant and offer unclear long-term patient outcomes. It is also difficult to time optimally the intervention to ensure that the benefits of treatment outweigh its risks. In this work we develop innovative fluid-structure interaction (FSI) model combining elements from immersed boundary (IB) and peridynamics (PD) methods to simulate tears in membranes. The new approach is termed as IB/PD method. We use non-ordinary state based PD to represent material hyperelasticity. Several test problems are taken to validate peridynamics approach to model structural dynamics, with and without accounting for failure in the structures. FSI simulations using IB/PD method are compared with immersed finite element method (IB/FE) to validate the new hybrid approach. NIH Award R01HL117163 NSF Award ACI 1450327.

Sucrose modulation of radiofrequency-induced heating rates and cell death.

PubMed

Pulikkathara, Merlyn; Mark, Colette; Kumar, Natasha; Zaske, Ana Maria; Serda, Rita E

2017-09-01

Applied radiofrequency (RF) energy induces hyperthermia in tissues, facilitating vascular perfusion This study explores the impact of RF radiation on the integrity of the luminal endothelium, and then predominately explores the impact of altering the conductivity of biologically-relevant solutions on RF-induced heating rates and cell death. The ability of cells to survive high sucrose (i.e. hyperosmotic conditions) to achieve lower conductivity as a mechanism for directing hyperthermia is evaluated. RF radiation was generated using a capacitively-coupled radiofrequency system operating at 13.56 MHz. Temperatures were recorded using a FLIR SC 6000 infrared camera. RF radiation reduced cell-to-cell connections among endothelial cells and altered cell morphology towards a more rounded appearance at temperatures reported to cause in vivo vessel deformation. Isotonic solutions containing high sucrose and low levels of NaCl displayed low conductivity and faster heating rates compared to high salt solutions. Heating rates were positively correlated with cell death. Addition of sucrose to serum similarly reduced conductivity and increased heating rates in a dose-dependent manner. Cellular proliferation was normal for cells grown in media supplemented with 125 mM sucrose for 24 hours or for cells grown in 750 mM sucrose for 10 minutes followed by a 24 h recovery period. Sucrose is known to form weak hydrogen bonds in fluids as opposed to ions, freeing water molecules to rotate in an oscillating field of electromagnetic radiation and contributing to heat induction. The ability of cells to survive temporal exposures to hyperosmotic (i.e. elevated sucrose) conditions creates an opportunity to use sucrose or other saccharides to selectively elevate heating in specific tissues upon exposure to a radiofrequency field.

Detection of the High-Level Aminoglycoside Resistance Gene aph(2")-Ib in Enterococcus faecium

PubMed Central

Kao, Susan J.; You, Il; Clewell, Don B.; Donabedian, Susan M.; Zervos, Marcus J.; Petrin, Joanne; Shaw, Karen J.; Chow, Joseph W.

2000-01-01

A new high-level gentamicin resistance gene, designated aph(2")-Ib, was cloned from Enterococcus faecium SF11770. The deduced amino acid sequence of the 897-bp open reading frame of aph(2")-Ib shares homology with the aminoglycoside-modifying enzymes AAC(6′)-APH(2"), APH(2")-Ic, and APH(2")-Id. The observed phosphotransferase activity is designated APH(2")-Ib. PMID:10991878

The severity of inflammation at onset of ulcerative colitis is not associated with IBS-like symptoms during clinical remission.

PubMed

Jonefjäll, Börje; Simrén, Magnus; Öhman, Lena; Lasson, Anders; Svedlund, Jan; Strid, Hans

2015-09-01

Symptoms compatible with irritable bowel syndrome (IBS) are common in patients with ulcerative colitis (UC) in clinical remission. It has been suggested that these symptoms might arise due to post-inflammatory changes comparable with post-infectious IBS. The aim was to study factors at new onset of UC that predict development of IBS-like symptoms during clinical remission. In total, 98 patients with new onset of UC were followed prospectively for 3 years with yearly follow-up visits. Data from the first visit at the onset of UC were compared between a group of patients who fulfilled the criteria for IBS while in remission (UCR+IBS) during follow-up and a group who did not (UCR-IBS). Among the UC patients, 87 met the criteria for clinical remission and 25 (29%) of these reported IBS-like symptoms in remission during follow-up. There was no difference in inflammatory disease activity at the initial flare or in the prevalence of previous IBS symptoms when comparing UCR+IBS and UCR-IBS patients. The UCR+IBS patients reported more severe gastrointestinal symptoms, including abdominal pain, during their primary flare. The severity and extent of inflammation at onset of UC do not seem to affect the development of IBS-like symptoms in UC patients during clinical remission. The high prevalence of IBS-like symptoms is not explained by pre-existing IBS. UCR+IBS patients reported more severe gastrointestinal symptoms at disease onset, which might indicate a more sensitive gastrointestinal tract in this category of patients. Copyright © 2015 European Crohn’s and Colitis Organisation (ECCO). Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.

sPLA2 IB induces human podocyte apoptosis via the M-type phospholipase A2 receptor

PubMed Central

Pan, Yangbin; Wan, Jianxin; Liu, Yipeng; Yang, Qian; Liang, Wei; Singhal, Pravin C.; Saleem, Moin A.; Ding, Guohua

2014-01-01

The M-type phospholipase A2 receptor (PLA2R) is expressed in podocytes in human glomeruli. Group IB secretory phospholipase A2 (sPLA2 IB), which is one of the ligands of the PLA2R, is more highly expressed in chronic renal failure patients than in controls. However, the roles of the PLA2R and sPLA2 IB in the pathogenesis of glomerular diseases are unknown. In the present study, we found that more podocyte apoptosis occurs in the kidneys of patients with higher PLA2R and serum sPLA2 IB levels. In vitro, we demonstrated that human podocyte cells expressed the PLA2R in the cell membrane. After binding with the PLA2R, sPLA2 IB induced podocyte apoptosis in a time- and concentration-dependent manner. sPLA2 IB-induced podocyte PLA2R upregulation was not only associated with increased ERK1/2 and cPLA2α phosphorylation but also displayed enhanced apoptosis. In contrast, PLA2R-silenced human podocytes displayed attenuated apoptosis. sPLA2 IB enhanced podocyte arachidonic acid (AA) content in a dose-dependent manner. These data indicate that sPLA2 IB has the potential to induce human podocyte apoptosis via binding to the PLA2R. The sPLA2 IB-PLA2R interaction stimulated podocyte apoptosis through activating ERK1/2 and cPLA2α and through increasing the podocyte AA content. PMID:25335547

Molecular Characterization and Growth Association of Two Apolipoprotein A-Ib Genes in Common Carp (Cyprinus carpio)

PubMed Central

Wang, Xinhua; Yu, Xiaomu; Tong, Jingou

2016-01-01

Apolipoprotein A-I (ApoA-I) is functionally involved in the transportation and metabolism of lipids in vertebrates. In this study, two isoforms of apoA-Ib in common carp (Cyprinus carpio L.) were characterized. Sequence comparison and phylogenetic analysis showed that C. carpio ApoA-Ib is relatively conserved within cyprinid fishes. During embryonic development, C. carpio apoA-Ib was first expressed at the stage of multi-cells, and the highest mRNA level was observed at the stage of optic vesicle. A ubiquitous expression pattern was detected in various tissues with extreme predominance in the liver. Significantly different expression levels were observed between light and heavy body weight groups and also in the compensatory growth test. Seventeen and eight single-nucleotide polymorphisms (SNPs) were identified in matured mRNA of the C. carpio apoA-Ib.1 and apoA-Ib.2, respectively. Two of these SNPs (apoA-Ib.2-g.183A>T and apoA-Ib.2-g.1753C>T) were significantly associated with body weight and body length in two populations of common carp. These results indicate that apoA-Ib may play an important role in the modulation of growth and development in common carp. PMID:27649163

Molecular Characterization and Growth Association of Two Apolipoprotein A-Ib Genes in Common Carp (Cyprinus carpio).

PubMed

Wang, Xinhua; Yu, Xiaomu; Tong, Jingou

2016-09-16

Apolipoprotein A-I (ApoA-I) is functionally involved in the transportation and metabolism of lipids in vertebrates. In this study, two isoforms of apoA-Ib in common carp (Cyprinus carpio L.) were characterized. Sequence comparison and phylogenetic analysis showed that C. carpio ApoA-Ib is relatively conserved within cyprinid fishes. During embryonic development, C. carpio apoA-Ib was first expressed at the stage of multi-cells, and the highest mRNA level was observed at the stage of optic vesicle. A ubiquitous expression pattern was detected in various tissues with extreme predominance in the liver. Significantly different expression levels were observed between light and heavy body weight groups and also in the compensatory growth test. Seventeen and eight single-nucleotide polymorphisms (SNPs) were identified in matured mRNA of the C. carpio apoA-Ib.1 and apoA-Ib.2, respectively. Two of these SNPs (apoA-Ib.2-g.183A>T and apoA-Ib.2-g.1753C>T) were significantly associated with body weight and body length in two populations of common carp. These results indicate that apoA-Ib may play an important role in the modulation of growth and development in common carp.

Epidemiology of Dyspepsia and Irritable Bowel Syndrome (IBS) in Medical Students of Northern India.

PubMed

Basandra, Sumeena; Bajaj, Divyansh

2014-12-01

Dyspepsia and Irritable Bowel Syndrome (IBS) are perhaps one of the most common gastrointestinal diseases universally. The prevalence of dyspepsia ranges from 7-40% while the prevalence of IBS ranges between 3-22% in population based studies worldwide. This study was conducted to estimate the prevalence, socio-demographic and lifestyle associated risk factors of Dyspepsia and IBS among medical college students of urban Delhi, Northern India. It is a cross-sectional study and was carried out from January to March 2014 at Maulana Azad Medical College, New Delhi, India. A total of 210 students from a Medical College were asked to complete a semi-structured questionnaire based on identification and socio-demographic data, questions pertaining to lifestyle and Rome III criteria. Of the valid 200 subjects, 90(45%) were males and 110(55%) were females, with a mean age of 20.43± 1.05 y. Majority of the subjects (diagnosed with uninvestigated dyspepsia and IBS) were in the age group of 18-20 y with female gender having higher odds for both. The prevalence of dyspepsia was 18% while that of IBS was 16.5%.Consumption of fatty food, cigarettes and low physical activity were observed as most significant correlates. Rome III criteria enables symptom based diagnosis of dyspepsia and IBS.The prevalence of dyspepsia and IBS in college students from Delhi is observed to be higher. Association with lifestyle related factors highlights the importance of modifications in their prevention.

6 Tips: IBS and Complementary Health Practices

MedlinePlus

... as anxiety, depression, disability, and quality of life. Probiotics . Probiotics such as Bifidobacterium and Lactobacillus are live microorganisms ... There is some preliminary evidence that suggests some probiotics may improve symptoms of IBS, such as abdominal ...

International Education, Values and Attitudes: A Critical Analysis of the International Baccalaureate (IB) Learner Profile

ERIC Educational Resources Information Center

Wells, John

2011-01-01

This article provides a critical review of the way that the International Baccalaureate (IB) promotes international education and international mindedness through the IB Learner Profile. While discussing theories of values and attitudes, and the teaching of values and theories of value acquisition, the paucity of such topics in IB texts is noted.…

Key role of glycoprotein Ib/V/IX and von Willebrand factor in platelet activation-dependent fibrin formation at low shear flow

PubMed Central

Cosemans, Judith M. E. M.; Schols, Saskia E. M.; Stefanini, Lucia; de Witt, Susanne; Feijge, Marion A. H.; Hamulyák, Karly; Deckmyn, Hans; Bergmeier, Wolfgang

2011-01-01

A microscopic method was developed to study the role of platelets in fibrin formation. Perfusion of adhered platelets with plasma under coagulating conditions at a low shear rate (250−1) resulted in the assembly of a star-like fibrin network at the platelet surface. The focal fibrin formation on platelets was preceded by rises in cytosolic Ca2+, morphologic changes, and phosphatidylserine exposure. Fibrin formation was slightly affected by αIIbβ3 blockage, but it was greatly delayed and reduced by the following: inhibition of thrombin or platelet activation; interference in the binding of von Willebrand factor (VWF) to glycoprotein Ib/V/IX (GpIb-V-IX); plasma or blood from patients with type 1 von Willebrand disease; and plasma from mice deficient in VWF or the extracellular domain of GpIbα. In this process, the GpIb-binding A1 domain of VWF was similarly effective as full-length VWF. Prestimulation of platelets enhanced the formation of fibrin, which was abrogated by blockage of phosphatidylserine. Together, these results show that, in the presence of thrombin and low shear flow, VWF-induced activation of GpIb-V-IX triggers platelet procoagulant activity and anchorage of a star-like fibrin network. This process can be relevant in hemostasis and the manifestation of von Willebrand disease. PMID:21037087

Heating rates in furnace atomic absorption using the L'vov platform

USGS Publications Warehouse

Koirtyohann, S.R.; Giddings, R.C.; Taylor, Howard E.

1984-01-01

Heating rate profiles for the furnace tube wall, the furnace atmosphere, and a L'vov platform were established for a range of conditions in a cyclically heated graphite atomizer. The tube wall profile was made by direct observation with a recording optical pyrometer. The sodium line reversal method was used to establish the heating rate of the furnace atmosphere, and appearance temperatures for a series metals of differing volatility was used to establish platform profiles. The tube wall heating rate was nearly linear at 2240??C s- until the desired temperature was reached after which the temperature remained constant. The furnace atmosphere reached a given temperature 0.2-0.4 s later than the tube wall through most of the atomize cycle. The platform lagged the tube wall 0.5-0.8 s. Under typical operating conditions the furnace atmosphere was 100-200??C cooler than the tube wall and at nearly constant temperature when the analyte vaporized from the platform. The L'vov platform causes the cyclically heated commercial furnace to approximate the behavior of a constant temperature furnace during atomization. ?? 1984.

Differential expression of CART in ewes with differing ovulation rates.

PubMed

Juengel, Jennifer L; French, Michelle C; Quirke, Laurel D; Kauff, Alexia; Smith, George W; Johnstone, Peter D

2017-04-01

We hypothesised that cocaine- and amphetamine-regulated transcript ( CARTPT ) would be differentially expressed in ewes with differing ovulation rates. Expression of mRNA for CARTPT , as well as LHCGR , FSHR , CYP19A1 and CYP17A1 was determined in antral follicles ≥1 mm in diameter collected during the follicular phase in ewes heterozygous for the Booroola and Inverdale genes (I+B+; average ovulation rate 4) and ++ contemporaries (++; average ovulation rate 1.8). In ++ ewes ( n  = 6), CARTPT was expressed in small follicles (1 to <3 mm diameter), where 18.8 ± 2.5% follicles expressed CARTPT CART peptide was also detected in follicular fluid of some follicles of ++ ewes. In I+B+ ewes, 5/6 ewes did not have any follicles that expressed CARTPT , and no CART peptide was detected in any follicle examined. Expression pattern of CYP19A1 differed between I+B+ and ++ ewes with an increased percentage of small and medium follicles (3 to <4.5 mm diameter) but decreased percentage of large follicles (≥4.5 mm diameter) expressing CYP19A1 in the I+B+ ewes. Many of the large follicles from the I+B+ ewes appeared non-functional and expression of LHCGR , FSHR , CYP17A1 and CYP19A1 was less than that observed in ++ ewes. Expression of FSHR and CYP17A1 was not different between groups in small and medium follicles, but LHCGR expression was approximately double in I+B+ ewes compared to that in ++ ewes. Thus, ewes with high ovulation rates had a distinct pattern of expression of CARTPT mRNA and protein compared to ewes with normal ovulation rates, providing evidence for CART being important in the regulation of ovulation rate. © 2017 Society for Reproduction and Fertility.

Age of air and heating rates: comparison of ERA-40 with ERA-Interim

NASA Astrophysics Data System (ADS)

Legras, B.; Fueglistaler, S.

2009-04-01

The age of air in the stratosphere is often used as a test for the good representation of the Brewer-Dobson circulation by atmospheric models. This is a critical requirement to modelize the distribution of long-lived species in chemical models. It is often advocated that using heating rates for vertical transport in the stratosphere performs better that standard analysed velocities from weather centers. This work is based on an extensive comparison of the age of air using 5 years of heating rates from the ERA-40 reanalysis and from the new ERA-interim reanalysis built with 4D-Var assimilation. The ERA-40 exhibits both too young ages with analyzed velocities and too old ages with heating rates. The reason for too young ages is spurious transport associated with too noisy wind, as a result of 3D-Var assimilation. Heating rates provide a much less noisy meridional circulation and preserve transport barriers and polar vortex confinement. However, excessive cooling near 30 hPa in the tropics blocks the ascending motion within the tropical pipe over extended periods of time inducing very old ages. This effect is usually corrected by an empirical correction which can exceed in some regions the calculated heating rate in magnitude, with opposite sign. We relate this correction to the assimilation temperature increment that is required to compensate the bias of the model, notably the excessive negative heat transport due to the noisy vertical velocities and the lack of mass conservation in the isentropic frame. The new ERA-interim exhibits much reduced noise in the vertical velocity and is ten times less diffusive than the ERA-40 in the tropics. Age of air is then found to be slightly older than given by the observations. The biases in the heating rate have also been considerably reduced with respect to ERA-40 and the assimilation increment is now only a fraction of the heating rate. The age of air is in fairly good aggreement with the observations at 20 km and higher

Clinical and Microbiological Effect of a Multispecies Probiotic Supplementation in Celiac Patients With Persistent IBS-type Symptoms: A Randomized, Double-Blind, Placebo-controlled, Multicenter Trial.

PubMed

Francavilla, Ruggiero; Piccolo, Maria; Francavilla, Antonio; Polimeno, Lorenzo; Semeraro, Francesco; Cristofori, Fernanda; Castellaneta, Stefania; Barone, Michele; Indrio, Flavia; Gobbetti, Marco; De Angelis, Maria

2018-04-23

The goals of this study were to evaluate the efficacy and safety of a probiotic mixture in patients with celiac disease (CD) with irritable bowel syndrome (IBS)-type symptoms despite a strict gluten-free diet (GFD). About 30% of patients with CD adherent to a GFD suffer from IBS-type symptoms; a possible cause resides in the imbalances of the intestinal microbiota in CD. Probiotics may represent a potential treatment. CD patients with IBS-type symptoms entered a prospective, double-blind, randomized placebo-controlled study. A 6-week treatment period was preceded by a 2-week run-in and followed by a 6-week follow-up phase. Clinical data were monitored throughout the study by validated questionnaires: IBS Severity Scoring System (IBS-SSS); Gastrointestinal Symptom Rating Scale (GSRS); Bristol Stool Form Scale (BSFS); and IBS Quality of Life Questionnaire (IBS-QOL). The fecal microbiota were assayed using plate counts and 16S rRNA gene-based analysis. In total, 109 patients were randomized to probiotics (n=54) or placebo (n=55). IBS-SSS and GSRS decreased significantly in probiotics, as compared with placebo [(-15.9%±14.8% vs. 8.2%±25.9%; P<0.001) and (-19.8%±16.6% vs. 12.9%±31.6%; P<0.001)], respectively. Treatment success was significantly higher in patients receiving probiotics, as compared with placebo (15.3% vs. 3.8%; P<0.04). Presumptive lactic acid bacteria, Staphylococcus and Bifidobacterium, increased in patients receiving probiotic treatment. No adverse events were reported. A 6-week probiotic treatment is effective in improving the severity of IBS-type symptoms, in CD patients on strict GFD, and is associated with a modification of gut microbiota, characterized by an increase of bifidobacteria.

Pyrolysis polygeneration of poplar wood: Effect of heating rate and pyrolysis temperature.

PubMed

Chen, Dengyu; Li, Yanjun; Cen, Kehui; Luo, Min; Li, Hongyan; Lu, Bin

2016-10-01

The pyrolysis of poplar wood were comprehensively investigated at different pyrolysis temperatures (400, 450, 500, 550, and 600°C) and at different heating rates (10, 30, and 50°C/min). The results showed that BET surface area of biochar, the HHV of non-condensable gas and bio-oil reached the maximum values of 411.06m(2)/g, 14.56MJ/m(3), and 14.39MJ/kg, under the condition of 600°C and 30°C/min, 600°C and 50°C/min, and 550°C and 50°C/min, respectively. It was conducive to obtain high mass and energy yield of bio-oil at 500°C and higher heating rate, while lower pyrolysis temperature and heating rate contributed towards obtaining both higher mass yield and energy yield of biochar. However, higher pyrolysis temperature and heating rate contributed to obtain both higher mass yield and energy yield of the non-condensable gas. In general, compared to the heating rate, the pyrolysis temperature had more effect on the product properties. Copyright © 2016 Elsevier Ltd. All rights reserved.

Politics and Pedagogy: Discursive Constructions in the IB "Theory of Knowledge--Guide"

ERIC Educational Resources Information Center

Smith, Nigel V.; Morgan, Mandy

2010-01-01

The International Baccalaureate (IB) curriculum is increasingly popular in both national and international secondary education settings. The "Theory of knowledge" (TOK) course is cast as the prime example of the international globalised values the IB Diploma represents. This article argues that such a positioning is contested within the TOK…

Reduced E-cadherin expression is associated with abdominal pain and symptom duration in a study of alternating and diarrhea predominant IBS.

PubMed

Wilcz-Villega, E; McClean, S; O'Sullivan, M

2014-03-01

Increased intestinal permeability and altered expression of tight junction (TJ) proteins may be implicated in the pathogenesis of irritable bowel syndrome (IBS). This study aimed to investigate the expression of adherens junction (AJ) protein E-cadherin and TJ proteins zonula occludens (ZO)-1 and claudin (CLD)-1 and associations with IBS symptoms. Junctional proteins were immunostained in cecal biopsy tissue of Rome II IBS patients (n = 34) comprising both alternating (IBS-A) and diarrhea predominant (IBS-D) subtypes, and controls (n = 12). IBS symptom duration, abdominal pain severity and stool frequency were assessed for IBS patients. Protein expression was determined by immunofluorescence. E-cadherin and ZO-1 protein expression was significantly lower (p = 0.03 and p = 0.016, respectively) in the cecal surface epithelium of the IBS group comprising both IBS-A and IBS-D subtypes. CLD-1 expression was not significantly altered compared with controls. On subtype analysis, ZO-1 expression was significantly reduced in both IBS-A and IBS-D compared with controls, whereas E-cadherin was reduced only in IBS-A. Lower E-cadherin expression was associated with longer symptoms duration specifically in IBS-A patients (rs = -0.76, p = 0.004). Reduced E-cadherin associated with abdominal pain severity in the overall IBS group (rs = -0.36, p = 0.041), but this association was unrelated to IBS subtype. E-cadherin protein expression in the cecum was significantly lower in IBS-A compared with controls and associated with longstanding symptoms. E-cadherin was further associated with abdominal pain severity in the IBS group overall, but unrelated to IBS subtype. Altered E-cadherin expression may provide novel insights into mechanisms underlying intestinal barrier dysfunction in IBS. © 2013 John Wiley & Sons Ltd.

Critical Success Factors for Lean Thinking in the Application of Industrialised Building System (IBS)

NASA Astrophysics Data System (ADS)

Yunus, Riduan; Noor, Siti Rahimah Mohd; Halid Abdullah, Abd; Nagapan, Sasitharan; Hamid, Abdul Rahim Abdul; Tajudin, Saiful Azhar Ahmad; Rohani Mat Jusof, Siti

2017-08-01

Productivity in the manufacturing process of building components can be increased by optimising each advantage that is available in each activity. Identification of critical success factors (CSFs) for lean thinking in the Industrialised Building System (IBS) will be able to minimise cost and reduce time needed to complete a project. The focus of lean thinking in construction is on the production process and the client’s requirement. In developing countries such as Malaysia, the integration of lean thinking in IBS applications is still low and there is a shortage of comprehensive strategies to integrate lean thinking. As key stakeholders, feedback from contractors, manufacturers, developers and the local authority will be able to help the identification of CSFs in integrating lean thinking in IBS applications. The data was collected through a questionnaire survey and analysed quantitatively. There are 31 CSFs for lean thinking in IBS which have been identified in this study. A conceptual model was developed to assist researchers in investigating the influences of CSFs for lean thinking in IBS applications. This study will assist construction players to improvise their manufacturing process in the implementation of IBS to eliminate unnecessary activities and focus instead on significant processes without generating physical and non-physical waste.

Stagnation-point heat-transfer rate predictions at aeroassist flight conditions

NASA Technical Reports Server (NTRS)

Gupta, Roop N.; Jones, Jim J.; Rochelle, William C.

1992-01-01

The results are presented for the stagnation-point heat-transfer rates used in the design process of the Aeroassist Flight Experiment (AFE) vehicle over its entire aeropass trajectory. The prediction methods used in this investigation demonstrate the application of computational fluid dynamics (CFD) techniques to a wide range of flight conditions and their usefulness in a design process. The heating rates were computed by a viscous-shock-layer (VSL) code at the lower altitudes and by a Navier-Stokes (N-S) code for the higher altitude cases. For both methods, finite-rate chemically reacting gas was considered, and a temperature-dependent wall-catalysis model was used. The wall temperature for each case was assumed to be radiative equilibrium temperature, based on total heating. The radiative heating was estimated by using a correlation equation. Wall slip was included in the N-S calculation method, and this method implicitly accounts for shock slip. The N-S/VSL combination of projection methods was established by comparison with the published benchmark flow-field code LAURA results at lower altitudes, and the direct simulation Monte Carlo results at higher altitude cases. To obtain the design heating rate over the entire forward face of the vehicle, a boundary-layer method (BLIMP code) that employs reacting chemistry and surface catalysis was used. The ratio of the VSL or N-S method prediction to that obtained from the boundary-layer method code at the stagnation point is used to define an adjustment factor, which accounts for the errors involved in using the boundary-layer method.

The communication in industrialised building system (IBS) construction project: Virtual environment

NASA Astrophysics Data System (ADS)

Pozin, Mohd Affendi Ahmad; Nawi, Mohd Nasrun Mohd

2017-10-01

Large portion of numbers team organization in the IBS construction sector is known are being fragmented. That is contributed from a segregation of construction activity thus create team working in virtually. Virtual team are the nature when teams are working in distributed area, across culture and time. Therefore, teams can be respond to the task without relocating to the site project and settle down a problem through information and communication technology (ICT). The emergence of virtual team are carry out by advancements in communication technologies as a medium to improve project team communication in project delivery process on IBS construction. Based on literature review from previous study and data collected from interviewing, this paper aim to identified communication challenges among project team members according to current project development practices in IBS construction project. Hence, in attempt to develop effective communication through the advantages of virtual team approach for IBS construction project. In order to ensure the data is gathered comprehensively and accurately, the data was collected from project managers by using semi structured interview method. It was found that virtual team approach could be enable competitive challenges on complexity in the construction project management process.

Influence of heat transfer rates on pressurization of liquid/slush hydrogen propellant tanks

NASA Technical Reports Server (NTRS)

Sasmal, G. P.; Hochstein, J. I.; Hardy, T. L.

1993-01-01

A multi-dimensional computational model of the pressurization process in liquid/slush hydrogen tank is developed and used to study the influence of heat flux rates at the ullage boundaries on the process. The new model computes these rates and performs an energy balance for the tank wall whereas previous multi-dimensional models required a priori specification of the boundary heat flux rates. Analyses of both liquid hydrogen and slush hydrogen pressurization were performed to expose differences between the two processes. Graphical displays are presented to establish the dependence of pressurization time, pressurant mass required, and other parameters of interest on ullage boundary heat flux rates and pressurant mass flow rate. Detailed velocity fields and temperature distributions are presented for selected cases to further illuminate the details of the pressurization process. It is demonstrated that ullage boundary heat flux rates do significantly effect the pressurization process and that minimizing heat loss from the ullage and maximizing pressurant flow rate minimizes the mass of pressurant gas required to pressurize the tank. It is further demonstrated that proper dimensionless scaling of pressure and time permit all the pressure histories examined during this study to be displayed as a single curve.

A TBP-containing multiprotein complex (TIF-IB) mediates transcription specificity of murine RNA polymerase I.

PubMed

Eberhard, D; Tora, L; Egly, J M; Grummt, I

1993-09-11

TIF-IB is a transcription factor which interacts with the mouse ribosomal gene promoter and nucleates the formation of an initiation complex containing RNA polymerase I (Pol I). We have purified this factor to near homogeneity and demonstrate that TIF-IB is a large complex (< 200 kDa) which contains several polypeptides. One of the subunits present in this protein complex is the TATA-binding protein (TBP) as revealed by copurification of TIF-IB activity and TBP over different chromatographic steps including immunoaffinity purification. In addition to TBP, three tightly associated proteins (TAFs-I) with apparent molecular weights of 95, 68, and 48 kDa are contained in this multimeric complex. This subunit composition is similar--but not identical--to the analogous human factor SL1. Depletion of TBP from TIF-IB-containing fractions by immunoprecipitation eliminates TIF-IB activity. Neither TBP alone nor fractions containing other TBP complexes are capable of substituting for TIF-IB activity. Therefore, TIF-IB is a unique complex with Pol I-specific TAFs distinct from other TBP-containing complexes. The identification of TBP as an integral part of the murine rDNA promoter-specific transcription initiation factor extends the previously noted similarity of transcriptional initiation by the three nuclear RNA polymerases and underscores the importance of TAFs in determining promoter specificity.

A TBP-containing multiprotein complex (TIF-IB) mediates transcription specificity of murine RNA polymerase I.

PubMed Central

Eberhard, D; Tora, L; Egly, J M; Grummt, I

1993-01-01

TIF-IB is a transcription factor which interacts with the mouse ribosomal gene promoter and nucleates the formation of an initiation complex containing RNA polymerase I (Pol I). We have purified this factor to near homogeneity and demonstrate that TIF-IB is a large complex (< 200 kDa) which contains several polypeptides. One of the subunits present in this protein complex is the TATA-binding protein (TBP) as revealed by copurification of TIF-IB activity and TBP over different chromatographic steps including immunoaffinity purification. In addition to TBP, three tightly associated proteins (TAFs-I) with apparent molecular weights of 95, 68, and 48 kDa are contained in this multimeric complex. This subunit composition is similar--but not identical--to the analogous human factor SL1. Depletion of TBP from TIF-IB-containing fractions by immunoprecipitation eliminates TIF-IB activity. Neither TBP alone nor fractions containing other TBP complexes are capable of substituting for TIF-IB activity. Therefore, TIF-IB is a unique complex with Pol I-specific TAFs distinct from other TBP-containing complexes. The identification of TBP as an integral part of the murine rDNA promoter-specific transcription initiation factor extends the previously noted similarity of transcriptional initiation by the three nuclear RNA polymerases and underscores the importance of TAFs in determining promoter specificity. Images PMID:8414971

Tegaserod in the treatment of irritable bowel syndrome (IBS) with constipation as the prime symptom

PubMed Central

Layer, Peter; Keller, Jutta; Loeffler, Helena; Kreiss, Andreas

2007-01-01

Irritable bowel syndrome with constipation (IBS-C) as the predominant bowel symptom is a prevalent disorder, characterized by recurring abdominal pain/discomfort, bloating, and constipation, and imposes a significant socio-economic burden. Traditional treatments generally address just one of the multiple IBS symptoms. The efficacy and safety profile of tegaserod, a serotonin 5-HT4 receptor agonist, has been demonstrated in several randomized, placebo-controlled, and open-label trials. This review discusses the major clinical trials of tegaserod, which have involved 8948 IBS patients. Overall, data reveal that tegaserod is an effective treatment for IBS-C, providing statistically significant relief of overall and multiple individual IBS-C symptoms (abdominal pain/discomfort, bloating, and constipation) in both placebo-controlled and “real-life” open-label settings. Repeat treatments with tegaserod were also shown to be effective, which is noteworthy given the chronic and episodic nature of IBS. Moreover, tegaserod was associated with improvements in patients’ quality of life and work productivity. Data also indicate that tegaserod is well tolerated over the short-term (4 weeks), long-term (12 months), and repeated treatments. Diarrhea is the only adverse event consistently associated with tegaserod and was generally mild and transient. Overall, tegaserod has been demonstrated to offer effective and well-tolerated treatment of IBS-C, providing patients with meaningful symptom relief. PMID:18360619

IBS and Potential Luminosity Improvement for RHIC Operation Below Transition Energy

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

Fedotov,A.

There is a strong interest in low-energy RHIC operations in the single-beam total energy range of 2.5-25 GeV/nucleon [1-3]. Collisions in this energy range, much of which is below nominal RHIC injection energy, will help to answer one of the key questions in the field of QeD about the existence and location of a critical point on the QCD phase diagram [4]. There have been several short test runs during 2006-2008 RHIC operations to evaluate RHIC operational challenges at these low energies [5]. Beam lifetimes observed during the test runs were limited by machine nonlinearities. This performance limit can bemore » improved with sufficient machine tuning. The next luminosity limitation comes from transverse and longitudinal Intra-beam Scattering (IBS), and ultimately from the space-charge limit. Detailed discussion of limiting beam dynamics effects and possible luminosity improvement with electron cooling can be found in Refs. [6-8]. For low-energy RHIC operation, particle losses from the RF bucket are of particular concern since the longitudinal beam size is comparable to the existing RF bucket at low energies. However, operation below transition energy allows us to exploit an Intra-beam Scattering (IBS) feature that drives the transverse and longitudinal beam temperatures towards equilibrium by minimizing the longitudinal diffusion rate using a high RF voltage. Simulation studies were performed with the goal to understand whether one can use this feature of IBS to improve luminosity of RHIC collider at low-energies. This Note presents results of simulations which show that additional luminosity improvement for low-energy RHIC project may be possible with high RF voltage from a 56 MHz superconducting RF cavity that is presently under development for RHIC.« less

Purification, crystallization and preliminary X-ray analysis of Enterococcus faecium aminoglycoside-2′′-phosphotransferase-Ib [APH(2′′)-Ib

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

Walanj, Rupa; Young, Paul; Baker, Heather M.

2005-04-01

APH(2′′)-Ib is an enzyme responsible for high-level gentamicin resistance in E. faecium isolates. Native crystals of this enzyme have been prepared and preliminary X-ray diffraction experiments have been undertaken. Bacterial resistance to the aminoglycoside antibiotics is primarily the result of deactivation of the drugs. Three families of enzymes are responsible for this activity, with one such family being the aminoglycoside phosphotransferases (APHs). The gene encoding one of these enzymes, APH(2′′)-Ib, has been cloned and the protein (comprising 299 amino-acid residues) expressed in Escherichia coli, purified and crystallized in the presence of 16%(w/v) PEG 3350 and gentamicin. The crystals belong tomore » the monoclinic space group P2{sub 1}, with approximate unit-cell parameters a = 79.7, b = 58.8, c = 81.4 Å, β = 98.4°, and preliminary X-ray diffraction analysis is consistent with the presence of two molecules in the asymmetric unit. Synchrotron diffraction data to approximately 2.65 Å resolution were collected from a native APH(2′′)-Ib crystal at beamline BL9-2 at SSRL (Stanford, CA, USA). Selenium-substituted crystals have also been produced and structure determination is proceeding.« less

Design and validation of a German version of the GSRS-IBS - an analysis of its psychometric quality and factorial structure.

PubMed

Schäfer, Sarah K; Weidner, Kathrin Julia; Hoppner, Jorge; Becker, Nicolas; Friedrich, Dana; Stokes, Caroline S; Lammert, Frank; Köllner, Volker

2017-12-04

Currently, a suitable questionnaire in German language is not available to monitor the progression and evaluate the severity of irritable bowel syndrome (IBS). Therefore, this study aimed to translate the Gastrointestinal Symptom Rating Scale for Irritable Bowel Syndrome (GSRS-IBS) into German and to evaluate its psychometric qualities and factorial structure. This study is based on a total sample of 372 participants [62.6% female, mean age = 41 years (SD = 17 years)]. 17.5% of the participants had a diagnosis of IBS, 19.9% were receiving treatment for chronic inflammatory bowel disease, 12.1% of the participants were recruited from a psychosomatic clinic, and 50.5% belonged to a control group. All participants completed the German version of GSRS-IBS (called Reizdarm-Fragebogen, RDF), as well as the Gießen Subjective Complaints List (GBB-24) and the Hospital Anxiety and Depression Scale - German version (HADS-D). The internal consistency of the RDF total scale was at least satisfactory in all subsamples (Cronbach's Alpha between .77 and .92), and for all subscales (Cronbach's Alpha between .79 and .91). The item difficulties (between .25 and .73) and the item-total correlations (between .48 and .83) were equally satisfactory. Principal axis analysis revealed a four-factorial structure of the RDF items, which mainly resembled the structure of the English original. Convergent validity was established based on substantial and significant correlations with the stomach-complaint scale of the GBB-24 (r = .71; p < .01) and the anxiety (r = .42; p < .01) and depression scales (r = .43; p < .01) of the HADS-D. The German version of the GSRS-IBS RDF proves to be an effective, reliable, and valid questionnaire for the assessment of symptom severity in IBS, which can be used in clinical practice as well as in clinical studies.

Serum Tryptophan Metabolite Levels During Sleep in Patients With and Without Irritable Bowel Syndrome (IBS).

PubMed

Heitkemper, Margaret M; Han, Claire Jungyoun; Jarrett, Monica E; Gu, Haiwei; Djukovic, Danijel; Shulman, Robert J; Raftery, Daniel; Henderson, Wendy A; Cain, Kevin C

2016-03-01

Poor sleep and stress are more frequently reported by women with irritable bowel syndrome (IBS) than by healthy control (HC) women. The pathophysiology linking poor sleep and stress to gastrointestinal symptoms remains poorly understood. We used a metabolomic approach to determine whether tryptophan (TRP) metabolites differ between women with and without IBS and whether the levels are associated with sleep indices and serum cortisol levels. This study sample included 38 women with IBS and 21 HCs. The women were studied in a sleep laboratory for three consecutive nights. On the third night of the study, a social stressor was introduced, then blood samples were drawn every 20 min and sleep indices were measured. Metabolites were determined by targeted liquid chromatography tandem mass spectrometry in a sample collected 1 hr after the onset of sleep. The ratios of each metabolite to TRP were used for analyses. Correlations were controlled for age and oral contraceptive use. Melatonin/TRP levels were lower (p = .005) in the IBS-diarrhea group versus the IBS-constipation and HC groups, and kynurenine/TRP ratios tended to be lower (p = .067) in the total IBS and IBS-diarrhea groups compared to HCs. Associations within the HC group included melatonin/TRP with polysomnography-sleep efficiency (r = .61, p = .006) and weaker positive correlations with the other ratios for either sleep efficiency or percentage time in rapid eye movement sleep (r > .40, p = .025-.091). This study suggests that reductions in early nighttime melatonin/TRP levels may be related to altered sleep quality in IBS, particularly those with diarrhea. © The Author(s) 2015.

Assessment of CFD Hypersonic Turbulent Heating Rates for Space Shuttle Orbiter

NASA Technical Reports Server (NTRS)

Wood, William A.; Oliver, A. Brandon

2011-01-01

Turbulent CFD codes are assessed for the prediction of convective heat transfer rates at turbulent, hypersonic conditions. Algebraic turbulence models are used within the DPLR and LAURA CFD codes. The benchmark heat transfer rates are derived from thermocouple measurements of the Space Shuttle orbiter Discovery windward tiles during the STS-119 and STS-128 entries. The thermocouples were located underneath the reaction-cured glass coating on the thermal protection tiles. Boundary layer transition flight experiments conducted during both of those entries promoted turbulent flow at unusually high Mach numbers, with the present analysis considering Mach 10{15. Similar prior comparisons of CFD predictions directly to the flight temperature measurements were unsatisfactory, showing diverging trends between prediction and measurement for Mach numbers greater than 11. In the prior work, surface temperatures and convective heat transfer rates had been assumed to be in radiative equilibrium. The present work employs a one-dimensional time-accurate conduction analysis to relate measured temperatures to surface heat transfer rates, removing heat soak lag from the flight data, in order to better assess the predictive accuracy of the numerical models. The turbulent CFD shows good agreement for turbulent fuselage flow up to Mach 13. But on the wing in the wake of the boundary layer trip, the inclusion of tile conduction effects does not explain the prior observed discrepancy in trends between simulation and experiment; the flight heat transfer measurements are roughly constant over Mach 11-15, versus an increasing trend with Mach number from the CFD.

Supply Chain Management on IBS Implementation in Klang Valley Construction Industry: Challenges and Issues

NASA Astrophysics Data System (ADS)

Azrizal Fauzi, Mohd; Hasim, Sulaiman; Awang, Anizah; Ridzuan, Ahmad Ruslan Mohd; Nur Yunus, Juzailah

2017-12-01

Industrialized Building System (IBS) is a system where the components of the building are manufactured in a factory and it will be transported to the site to form the structures. The supply chain management (SCM) is a system where the delivery flows of the IBS products from manufacturers to the site. The aim of this research is to identify the major challenges and to analyze the issues on IBS implementation in SCM in Klang Valley from the manufacturers perspective. The methodology used in this paper is based on primary data through questionnaire and interview. Questionnaires were sent to the Manufacturers. It can be concluded that this paper attempts to present more on the challenges and issues that those companies of manufacturers faced during their success journey in finding integration in their supply chain. The main contributions of this paper are integrating all the supply chain integration challenges and issues on IBS. Therefore, these contributions will be helpful for the organization of manufacturers and IBS players that establish the integration in their SCM.

Changes in heart rate variability during the induction and decay of heat acclimation.

PubMed

Flouris, Andreas D; Poirier, Martin P; Bravi, Andrea; Wright-Beatty, Heather E; Herry, Christophe; Seely, Andrew J; Kenny, Glen P

2014-10-01

We evaluated the changes in core temperature, heart rate, and heart rate variability (HRV) during the induction and decay of heat acclimation. Ten males (23 ± 3 years; 79.5 ± 3.5 kg; 15.2 ± 4.5 percent body fat; 51.13 ± 4.61 mLO(2)∙kg(-1)∙min(-1) peak oxygen uptake) underwent a 14-day heat acclimation protocol comprising of 90-min cycling at ~50 % peak oxygen uptake at 40 °C and ~20 % relative humidity. Core temperature, heart rate, and 102 HRV measures were recorded during a heat tolerance test conducted at baseline (day 0) and at the end of the induction (day 14) and decay (day 28) phases. Heat acclimation resulted in significantly reduced core temperature [rectal (χ (2) = 1298.14, p < 0.001); esophageal (χ (2) = 1069.88, p < 0.001)] and heart rate (χ (2) = 1230.17, p < 0.001). Following the decay phase, 26, 40, and 60 % of the heat acclimation-induced reductions in rectal temperature, esophageal temperature, and heart rate, respectively, were lost. Heat acclimation was accompanied by profound and broad changes in HRV: at the end of the induction phase, 75 of the 102 variability measures computed were significantly different (p < 0.001), compared to only 47 of the 102 at the end of the decay phase. Heat acclimation is accompanied by reduced core temperature, significant bradycardia, and marked alterations in HRV, which we interpret as being related to vagal dominance. The observed changes in core temperature persist for at least 2 weeks of non-exposure to heat, while the changes in heart rate and HRV decay faster and are only partly evident after 2 weeks of non-exposure to heat.

Parameter study of r-process lanthanide production and heating rates in kilonovae

NASA Astrophysics Data System (ADS)

Lippuner, Jonas; Roberts, Luke F.

2015-04-01

Explosive r-process nucleosynthesis in material ejected during compact object mergers may lead to radioactively powered transients called kilonovae. The timescale and peak luminosity of these transients are sensitive to the composition of the material after nuclear burning ceases, as the composition determines the local heating rate from nuclear decays and the opacity. The presence of lanthanides in the ejecta can drastically increase the opacity. We use the new general-purpose nuclear reaction network SkyNet to run a parameter study of r-process nucleosynthesis for a range of initial electron fractions Ye, initial entropies s, and density decay timescales τ. We find that the ejecta is lanthanide-free for Ye >~ 0 . 22 - 0 . 3 , depending on s and τ. The heating rate is insensitive to s and τ, but certain, larger values of Ye lead to reduced heating rates, because single nuclides dominate the heating. With a simple model we estimate the luminosity, time, and effective temperature at the peak of the light curve. Since the opacity is much lower in the lanthanide-free case, we find the luminosity peaks much earlier at ~ 1 day vs. ~ 15 days in the lanthanide-rich cases. Although there is significant variation in the heating rate with Ye, changes in the heating rate do not mitigate the effect of the lanthanides. This research is partially supported by NSF under Award Numbers AST-1333520 and AST-1205732.

Time dependent heat transfer rates in high Reynolds number hypersonic flowfields

NASA Technical Reports Server (NTRS)

Flanagan, Michael J.

1992-01-01

Time dependent heat transfer rates have been calculated from time dependent temperature measurements in the vicinity of shock-wave boundary-layer interactions due to conical compression ramps on an axisymmetric body. The basic model is a cylindrical body with a 10 degree conical nose. Four conical ramps, 20, 25, 30, and 35 degrees serve as shock wave generators. Flowfield surveys have been made in the vicinity of the conical ramp vertex, the separation point, and the reattachment point. A significant effort was made to characterize the natural frequencies and relative powers of the resulting fluctuations in heat transfer rates. This research effort, sponsored jointly by NASA and the Air Force, was conducted in the Air Force Flight Dynamics Directorate High Reynolds Facility. The nominal freestream Mach number was 6, and the freestream Reynolds numbers ranged from 2.2 million/ft to 30.0 million/ft. Experimental results quantify temperature response and the resulting heat transfer rates as a function of ramp angle and Reynolds number. The temperature response within the flowfield appears to be steady-state for all compression ramp angles and all Reynolds numbers, and hence, the heat transfer rates appear to be steady-state.

Time dependent heat transfer rates in high Reynolds number hypersonic flowfields

NASA Astrophysics Data System (ADS)

Flanagan, Michael J.

1992-09-01

Time dependent heat transfer rates have been calculated from time dependent temperature measurements in the vicinity of shock-wave boundary-layer interactions due to conical compression ramps on an axisymmetric body. The basic model is a cylindrical body with a 10 degree conical nose. Four conical ramps, 20, 25, 30, and 35 degrees serve as shock wave generators. Flowfield surveys have been made in the vicinity of the conical ramp vertex, the separation point, and the reattachment point. A significant effort was made to characterize the natural frequencies and relative powers of the resulting fluctuations in heat transfer rates. This research effort, sponsored jointly by NASA and the Air Force, was conducted in the Air Force Flight Dynamics Directorate High Reynolds Facility. The nominal freestream Mach number was 6, and the freestream Reynolds numbers ranged from 2.2 million/ft to 30.0 million/ft. Experimental results quantify temperature response and the resulting heat transfer rates as a function of ramp angle and Reynolds number. The temperature response within the flowfield appears to be steady-state for all compression ramp angles and all Reynolds numbers, and hence, the heat transfer rates appear to be steady-state.

Streptococcus sanguinis Class Ib Ribonucleotide Reductase

PubMed Central

Makhlynets, Olga; Boal, Amie K.; Rhodes, DeLacy V.; Kitten, Todd; Rosenzweig, Amy C.; Stubbe, JoAnne

2014-01-01

Streptococcus sanguinis is a causative agent of infective endocarditis. Deletion of SsaB, a manganese transporter, drastically reduces S. sanguinis virulence. Many pathogenic organisms require class Ib ribonucleotide reductase (RNR) to catalyze the conversion of nucleotides to deoxynucleotides under aerobic conditions, and recent studies demonstrate that this enzyme uses a dimanganese-tyrosyl radical (MnIII2-Y•) cofactor in vivo. The proteins required for S. sanguinis ribonucleotide reduction (NrdE and NrdF, α and β subunits of RNR; NrdH and TrxR, a glutaredoxin-like thioredoxin and a thioredoxin reductase; and NrdI, a flavodoxin essential for assembly of the RNR metallo-cofactor) have been identified and characterized. Apo-NrdF with FeII and O2 can self-assemble a diferric-tyrosyl radical (FeIII2-Y•) cofactor (1.2 Y•/β2) and with the help of NrdI can assemble a MnIII2-Y• cofactor (0.9 Y•/β2). The activity of RNR with its endogenous reductants, NrdH and TrxR, is 5,000 and 1,500 units/mg for the Mn- and Fe-NrdFs (Fe-loaded NrdF), respectively. X-ray structures of S. sanguinis NrdIox and MnII2-NrdF are reported and provide a possible rationale for the weak affinity (2.9 μm) between them. These streptococcal proteins form a structurally distinct subclass relative to other Ib proteins with unique features likely important in cluster assembly, including a long and negatively charged loop near the NrdI flavin and a bulky residue (Thr) at a constriction in the oxidant channel to the NrdI interface. These studies set the stage for identifying the active form of S. sanguinis class Ib RNR in an animal model for infective endocarditis and establishing whether the manganese requirement for pathogenesis is associated with RNR. PMID:24381172

Better Understanding and Recognition of the Disconnects, Experiences, and Needs of Patients with Irritable Bowel Syndrome with Constipation (BURDEN IBS-C) Study: Results of an Online Questionnaire.

PubMed

Quigley, Eamonn M M; Horn, John; Kissous-Hunt, Michele; Crozier, Robert A; Harris, Lucinda A

2018-06-26

The BURDEN IBS-C study was conducted to better understand the experiences, attitudes, and unmet needs of sufferers of irritable bowel syndrome with constipation (IBS-C) in comparison to the perceptions and challenges of healthcare providers (HCPs) who treat IBS-C patients. This was an author-developed, online questionnaire using KnowledgePanel ® to survey individuals with IBS-C (N = 1311). HCPs participated in a complementary online questionnaire and were recruited separately (N = 331). The study was fielded from June 29, 2016, to January 30, 2017. Most patients had used (86%) and/or were using (76%) over-the-counter treatments for their IBS-C, with 12% currently on prescription therapy. At the time this study was conducted, 66% and 63% were not satisfied/completely satisfied with over-the-counter or prescription treatment, respectively, citing inadequate efficacy (55%) and side effects (39%), most commonly diarrhea, as common reasons for dissatisfaction. IBS-C respondents most commonly reported feeling frustrated (43%) and stressed (28%) regarding IBS-C, though 39% were accepting of IBS-C as part of daily life. HCPs were aligned with patients in thinking that patients were frustrated (76%) and stressed (65%) but HCPs were less likely to recognize that patients had become accepting of their IBS-C (13%). Most HCPs (79%) were not satisfied/completely satisfied with the prescription treatments available at the time this study was conducted. Inadequate response rates to current therapies (55%) and treatment adherence/compliance issues (58%) were the most frequent challenges encountered by HCPs. IBS-C respondents reported that their symptoms impacted productivity and personal activity, on average, 4 and 3 days/month, respectively. These results suggest that current management pathways may not be adequately addressing the symptoms and needs of individuals with IBS-C, most notably side effects and lack of efficacy. Patients and HCPs expressed dissatisfaction

Experimental study on latent heat storage characteristics of W/O emulsion -Supercooling rate of dispersed water drops by direct contact heat exchange-

NASA Astrophysics Data System (ADS)

Morita, Shin-ichi; Hayamizu, Yasutaka; Horibe, Akihiko; Haruki, Naoto; Inaba, Hideo

2013-04-01

Recently, much attention has been paid to investigate the latent heat storage system. Using of ice heat storage system brings an equalization of electric power demand, because it will solved the electric -power-demand-concentration on day-time of summer by the air conditioning. The flowable latent heat storage material, Oil/Water type emulsion, microencapsulated latent heat material-water mixture or ice slurry, etc., is enable to transport the latent heat in a pipe. The flowable latent heat storage material can realize the pipe size reduction and system efficiency improvement. Supercooling phenomenon of the dispersed latent heat storage material in continuous phase brings the obstruction of latent heat storage. The latent heat storage rates of dispersed water drops in W/O (Water/Oil) emulsion are investigated experimentally in this study. The water drops in emulsion has the diameter within 3 ˜ 25μm, the averaged water drop diameter is 7.3μm and the standard deviation is 2.9μm. The direct contact heat exchange method is chosen as the phase change rate evaluation of water drops in W/O emulsion. The supercooled temperature and the cooling rate are set as parameters of this study. The evaluation is performed by comparison between the results of this study and the past research. The obtained experimental result is shown that the 35K or more degree from melting point brings 100% latent heat storage rate of W/O emulsion. It was clarified that the supercooling rate of dispersed water particles in emulsion shows the larger value than that of the bulk water.

Post-infectious irritable bowel syndrome (PI-IBS) after infection with Shiga-like toxin-producing Escherichia coli (STEC) O104:H4: A cohort study with prospective follow-up.

PubMed

Andresen, Viola; Löwe, Bernd; Broicher, Wiebke; Riegel, Björn; Fraedrich, Katharina; von Wulffen, Moritz; Gappmayer, Kerrin; Wegscheider, Karl; Treszl, András; Rose, Matthias; Layer, Peter; Lohse, Ansgar W

2016-02-01

In May/June 2011, the new Shiga-like toxin-producing Escherichia coli (STEC) strain O104:H4 caused the severest outbreak ever recorded of hemorrhagic enterocolitis in 3842 patients in Germany. As bacterial enterocolitis is an established risk factor of subsequent irritable bowel syndrome (IBS), we aimed to estimate prevalence and incidence of post-infectious (PI)-IBS after six and 12 months in a cohort of STEC O104:H4 patients and to prospectively identify associated somatic and psychometric risk factors. A total of 389 patients were studied prospectively at baseline and at six and 12 months after STEC infection using STEC disease-related questionnaires and validated instruments for IBS (Rome III) and psychological factors. Frequencies and logistic regression models using multiple imputations were applied to assess predictor variables. Prevalence of IBS increased from 9.8% prior to STEC infection to 23.6% at six and 25.3% at 12 months after STEC infection. In patients without IBS symptoms prior to STEC infection, incidence of new IBS was 16.9%. Logistic regression models indicated higher somatization and anxiety scores as risk factors for, and mesalazine treatment during, STEC infection as the only significant protective factor against IBS. No other factor analyzed, including disease severity, showed an association. PI-IBS rates following this unusually severe STEC outbreak were similar to what has been observed after other infectious gastroenteritis outbreaks. Our findings suggest that mesalazine may have reduced the risk of subsequent PI-IBS. As altered mucosal immune activity is a pivotal pathogenic factor in PI-IBS, our observation of a potential protective effect of mesalazine might be explained by its known modulatory action on mucosal immunity, and may warrant further investigation.

Post-infectious irritable bowel syndrome (PI-IBS) after infection with Shiga-like toxin-producing Escherichia coli (STEC) O104:H4: A cohort study with prospective follow-up

PubMed Central

Löwe, Bernd; Broicher, Wiebke; Riegel, Björn; Fraedrich, Katharina; von Wulffen, Moritz; Gappmayer, Kerrin; Wegscheider, Karl; Treszl, András; Rose, Matthias; Layer, Peter; Lohse, Ansgar W

2015-01-01

Background In May/June 2011, the new Shiga-like toxin-producing Escherichia coli (STEC) strain O104:H4 caused the severest outbreak ever recorded of hemorrhagic enterocolitis in 3842 patients in Germany. Objectives As bacterial enterocolitis is an established risk factor of subsequent irritable bowel syndrome (IBS), we aimed to estimate prevalence and incidence of post-infectious (PI)-IBS after six and 12 months in a cohort of STEC O104:H4 patients and to prospectively identify associated somatic and psychometric risk factors. Methods A total of 389 patients were studied prospectively at baseline and at six and 12 months after STEC infection using STEC disease-related questionnaires and validated instruments for IBS (Rome III) and psychological factors. Frequencies and logistic regression models using multiple imputations were applied to assess predictor variables. Results Prevalence of IBS increased from 9.8% prior to STEC infection to 23.6% at six and 25.3% at 12 months after STEC infection. In patients without IBS symptoms prior to STEC infection, incidence of new IBS was 16.9%. Logistic regression models indicated higher somatization and anxiety scores as risk factors for, and mesalazine treatment during, STEC infection as the only significant protective factor against IBS. No other factor analyzed, including disease severity, showed an association. Conclusions PI-IBS rates following this unusually severe STEC outbreak were similar to what has been observed after other infectious gastroenteritis outbreaks. Our findings suggest that mesalazine may have reduced the risk of subsequent PI-IBS. As altered mucosal immune activity is a pivotal pathogenic factor in PI-IBS, our observation of a potential protective effect of mesalazine might be explained by its known modulatory action on mucosal immunity, and may warrant further investigation. PMID:26966532

Prognostic factors of pathologic stage IB non-small cell lung cancer.

PubMed

Yano, Motoki; Sasaki, Hidefumi; Moriyama, Satoru; Kawano, Osamu; Hikosaka, Yu; Fujii, Yoshitaka

2011-01-01

In pathologic IB (pIB) non-small cell lung cancer, especially in adenocarcinoma, adjuvant chemotherapy with uracil-tegafur is widely recognized as being effective. The aim of this study was to determine the prognostic factors of pIB disease. Sixty patients who were diagnosed with pIB disease between 2004 and 2007 were retrospectively analyzed. Of 60 patients, 22 (36.7%) opted for surgery plus adjuvant chemotherapy with uracil-tegafur, whereas 38 (63.3%) opted for surgery only. The oral administration dose of uracil-tegafur was 400 mg/body. Compliance of adjuvant chemotherapy with uracil-tegafur was 65.5% in 12 months, 57.3% in 24 months. Adjuvant chemotherapy was interrupted in 11 patients because of the recurrence of disease in 3 patients and adverse reaction in 8 patients. Anorexia was the most common adverse reaction. The larger tumor diameter (5 cm<) and p2 pleural invasion were the worse prognostic factors in disease free survival in a univariate analysis and a multivariate analysis (hazard ratio = 0.26 and 0.25; p = 0.028 and 0.032, respectively). The prognosis of the patients with pleural invasion and a tumor diameter >5 cm was poor, and these, partly support the forthcoming classification.

Stimulation of ANP secretion by 2-Cl-IB-MECA through A(3) receptor and CaMKII.

PubMed

Yuan, Kuichang; Bai, Guang Yi; Park, Woo Hyun; Kim, Sung Zoo; Kim, Suhn Hee

2008-12-01

Adenosine is a potent mediator of myocardial protection against hypertrophy via A(1) or A(3) receptors that may be partly related to atrial natriuretic peptide (ANP) release. However, little is known about the possible involvement of the A(3) receptor on ANP release. We studied the effects of the A(3) receptor on atrial functions and its modification in hypertrophied atria. A selective A(3) receptor agonist, 2-chloro-N(6)-(3-iodobenzyl) adenosine-5'-N-methyluronamide (2-CI-IB-MECA), was perfused into isolated, beating rat atria with and without receptor modifiers. 2-CI-IB-MECA dose-dependently increased the ANP secretion, which was blocked by the A(3) receptor antagonist, but the increased atrial contractility and decreased cAMP levels induced by 30muM 2-CI-IB-MECA were not affected. The 100muM 2-(1-hexylnyl)-N-methyladenosine (HEMADO) and N(6)-(3-iodobenzyl) adenosine-5'-N-methyluronamide (IB-MECA), A(3) receptor agonist, also stimulated the ANP secretion without positive inotropy. The potency for the stimulation of ANP secretion was 2-CI-IB-MECA>IB-MECA=HEMADO. The inhibition of the ryanodine receptor or calcium/calmodulin-dependent kinase II (CaMKII) attenuated 2-CI-IB-MECA-induced ANP release, positive inotropy, and translocation of extracellular fluid. However, the inhibition of L-type Ca(2+) channels, sarcoplasmic reticulum Ca(2+)-reuptake, phospholipase C or inositol 1,4,5-triphosphate receptors did not affect these parameters. 2-CI-IB-MECA decreased cAMP level, which was blocked only with an inhibitor of CaMKII or adenylyl cyclase. These results suggest that 2-CI-IB-MECA increases the ANP secretion mainly via A(3) receptor activation and positive inotropy by intracellular Ca(2+) regulation via the ryanodine receptor and CaMKII.

A purified transcription factor (TIF-IB) binds to essential sequences of the mouse rDNA promoter.

PubMed Central

Clos, J; Buttgereit, D; Grummt, I

1986-01-01

A transcription factor that is specific for mouse rDNA has been partially purified from Ehrlich ascites cells. This factor [designated transcription initiation factor (TIF)-IB] is required for accurate in vitro synthesis of mouse rRNA in addition to RNA polymerase I and another regulatory factor, TIF-IA. TIF-IB activity is present in extracts both from growing and nongrowing cells in comparable amounts. Prebinding competition experiments with wild-type and mutant templates suggest that TIF-IB interacts with the core control element of the rDNA promoter, which is located immediately upstream of the initiation site. The specific binding of TIF-IB to the RNA polymerase I promoter is demonstrated by exonuclease III protection experiments. The 3' border of the sequences protected by TIF-IB is shown to be on the coding strand at position -21 and on the noncoding strand at position -7. The results suggest that direct binding of TIF-IB to sequences in the core promoter element is the mechanism by which this factor imparts promoter selectivity to RNA polymerase I. Images PMID:3456157

SYMPOSIUM REPORT: An Evidence-Based Approach to IBS and CIC: Applying New Advances to Daily Practice

PubMed Central

Chey, William D.

2017-01-01

Many nonpharmacologic and pharmacologic therapies are available to manage irritable bowel syndrome (IBS) and chronic idiopathic constipation (CIC). The American College of Gastroenterology (ACG) regularly publishes reviews on IBS and CIC therapies. The most recent of these reviews was published by the ACG Task Force on the Management of Functional Bowel Disorders in 2014. The key objective of this review was to evaluate the efficacy of therapies for IBS or CIC compared with placebo or no treatment in randomized controlled trials. Evidence-based approaches to managing diarrhea-predominant IBS include dietary measures, such as a diet low in gluten and fermentable oligo-, di-, and monosaccharides and polyols (FODMAPs); loperamide; antispasmodics; peppermint oil; probiotics; tricyclic antidepressants; alosetron; eluxadoline, and rifaximin. Evidence-based approaches to managing constipation-predominant IBS and CIC include fiber, stimulant laxatives, polyethylene glycol, selective serotonin reuptake inhibitors, lubiprostone, and guanylate cyclase agonists. With the growing evidence base for IBS and CIC therapies, it has become increasingly important for clinicians to assess the quality of evidence and understand how to apply it to the care of individual patients. PMID:28729815

Finite-Rate Ablation Boundary Conditions for Carbon-Phenolic Heat-Shield

NASA Technical Reports Server (NTRS)

Chen, Y.-K.; Milos, Frank S.

2003-01-01

A formulation of finite-rate ablation surface boundary conditions, including oxidation, nitridation, and sublimation of carbonaceous material with pyrolysis gas injection, has been developed based on surface species mass conservation. These surface boundary conditions are discretized and integrated with a Navier-Stokes solver. This numerical procedure can predict aerothermal heating, chemical species concentration, and carbonaceous material ablation rate over the heatshield surface of re-entry space vehicles. In this study, the gas-gas and gas-surface interactions are established for air flow over a carbon-phenolic heatshield. Two finite-rate gas-surface interaction models are considered in the present study. The first model is based on the work of Park, and the second model includes the kinetics suggested by Zhluktov and Abe. Nineteen gas phase chemical reactions and four gas-surface interactions are considered in the present model. There is a total of fourteen gas phase chemical species, including five species for air and nine species for ablation products. Three test cases are studied in this paper. The first case is a graphite test model in the arc-jet stream; the second is a light weight Phenolic Impregnated Carbon Ablator at the Stardust re-entry peak heating conditions, and the third is a fully dense carbon-phenolic heatshield at the peak heating point of a proposed Mars Sample Return Earth Entry Vehicle. Predictions based on both finite-rate gas- surface interaction models are compared with those obtained using B' tables, which were created based on the chemical equilibrium assumption. Stagnation point convective heat fluxes predicted using Park's finite-rate model are far below those obtained from chemical equilibrium B' tables and Zhluktov's model. Recession predictions from Zhluktov's model are generally lower than those obtained from Park's model and chemical equilibrium B' tables. The effect of species mass diffusion on predicted ablation rate is also

Lactulose Breath Test Gas Production in Childhood IBS Is Associated With Intestinal Transit and Bowel Movement Frequency.

PubMed

Chumpitazi, Bruno P; Weidler, Erica M; Shulman, Robert J

2017-04-01

In adults with irritable bowel syndrome (IBS), bacterial gas production (colonic fermentation) is related to both symptom generation and intestinal transit. Whether gas production affects symptom generation, psychosocial distress, or intestinal transit in childhood IBS is unknown. Children (ages 7-17 years) with pediatric Rome III IBS completed validated psychosocial questionnaires and a 2-week daily diary capturing pain and stooling characteristics. Stool form determined IBS subtype. Subjects then completed a 3-hour lactulose breath test for measurement of total breath hydrogen and methane production. Carmine red was used to determine whole intestinal transit time. A total of 87 children (mean age 13 ± 2.6 [standard deviation] years) were enrolled, of whom 50 (57.5%) were girls. All children produced hydrogen and 51 (58.6%) produced methane. Hydrogen and methane production did not correlate with either abdominal pain frequency/severity or psychosocial distress. Hydrogen and methane production did not differ significantly by IBS subtype. Methane production correlated positively with whole intestinal transit time (r = 0.31, P < 0.005) and inversely with bowel movement frequency (r = -0.245, P < 0.05). Methane production (threshold 3 ppm) as a marker for identifying IBS-C had a sensitivity of 60% and specificity of 42.9%. Lactulose breath test total methane production may serve as a biomarker of whole intestinal transit time and bowel movement frequency in children with IBS. In children with IBS, lactulose breath test hydrogen and methane production did not, however, correlate with abdominal pain, IBS subtype, or psychosocial distress.

39. VIEW OF CHRYSLER WORKERS LOADING A SATURN IB BOOSTER ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

39. VIEW OF CHRYSLER WORKERS LOADING A SATURN IB BOOSTER INTO THE EAST POSITION ON THE STATIC TEST TOWER. AS THE MAIN CONTRACTOR OF THE SATURN IB BOOSTER, CHRYSLER TOOK OVER OPERATIONS OF THE EAST POSITION OF THE STATIC TEST TOWER IN 1963. THAT SAME YEAR, THE WEST POSITION OF THE TEST TOWER WAS MODIFIED (AS SEEN IN THE PHOTO) FOR RESEARCH AND DEVELOPMENT TESTS OF THE SATURN V BOOSTER'S ENGINE, THE F-1. MARCH 1963, MSFC PHOTO LAB. - Marshall Space Flight Center, Saturn Propulsion & Structural Test Facility, East Test Area, Huntsville, Madison County, AL

FODMAPs alter symptoms and the metabolome of patients with IBS: a randomised controlled trial.

PubMed

McIntosh, Keith; Reed, David E; Schneider, Theresa; Dang, Frances; Keshteli, Ammar H; De Palma, Giada; Madsen, Karen; Bercik, Premysl; Vanner, Stephen

2017-07-01

To gain mechanistic insights, we compared effects of low fermentable oligosaccharides, disaccharides and monosaccharides and polyols (FODMAP) and high FODMAP diets on symptoms, the metabolome and the microbiome of patients with IBS. We performed a controlled, single blind study of patients with IBS (Rome III criteria) randomised to a low (n=20) or high (n=20) FODMAP diet for 3 weeks. Symptoms were assessed using the IBS symptom severity scoring (IBS-SSS). The metabolome was evaluated using the lactulose breath test (LBT) and metabolic profiling in urine using mass spectrometry. Stool microbiota composition was analysed by 16S rRNA gene profiling. Thirty-seven patients (19 low FODMAP; 18 high FODMAP) completed the 3-week diet. The IBS-SSS was reduced in the low FODMAP diet group (p<0.001) but not the high FODMAP group. LBTs showed a minor decrease in H 2 production in the low FODMAP compared with the high FODMAP group. Metabolic profiling of urine showed groups of patients with IBS differed significantly after the diet (p<0.01), with three metabolites (histamine, p-hydroxybenzoic acid, azelaic acid) being primarily responsible for discrimination between the two groups. Histamine, a measure of immune activation, was reduced eightfold in the low FODMAP group (p<0.05). Low FODMAP diet increased Actinobacteria richness and diversity, and high FODMAP diet decreased the relative abundance of bacteria involved in gas consumption. IBS symptoms are linked to FODMAP content and associated with alterations in the metabolome. In subsets of patients, FODMAPs modulate histamine levels and the microbiota, both of which could alter symptoms. NCT01829932. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

The ties that bind: perceived social support, stress, and IBS in severely affected patients.

PubMed

Lackner, J M; Brasel, A M; Quigley, B M; Keefer, L; Krasner, S S; Powell, C; Katz, L A; Sitrin, M D

2010-08-01

This study assessed the association between social support and the severity of irritable bowel syndrome (IBS) symptoms in a sample of severely affected IBS patients recruited to an NIH-funded clinical trial. In addition, we examined if the effects of social support on IBS pain are mediated through the effects on stress. Subjects were 105 Rome II diagnosed IBS patients (F = 85%) who completed seven questionnaires which were collected as part of a pretreatment baseline assessment. Partial correlations were conducted to clarify the relationships between social support and clinically relevant variables with baseline levels of psychopathology, holding constant number of comorbid medical diseases, age, gender, marital status, ethnicity, and education. Analyses indicated that social support was inversely related to IBS symptom severity. Social support was positively related with less severe pain. A similar pattern of data was found for perceived stress but not quality of life impairment. Regression analyses examined if the effects of social support on pain are mediated by stress. The effects of social support on bodily pain were mediated by stress such that the greater the social support the less stress and the less pain. This effect did not hold for symptom severity, quality of life, or psychological distress. This study links the perceived adequacy of social support to the global severity of symptoms of IBS and its cardinal symptom (pain). It also suggests that the mechanism by which social support alleviates pain is through a reduction in stress levels.

Critical ICT-Inhibiting Factors on IBS Production Management Processes in the Malaysia Construction Industry

NASA Astrophysics Data System (ADS)

Ern, Peniel Ang Soon; Kasim, Narimah; Hamid, Zuhairi Abd; Chen, Goh Kai

2017-10-01

Industrialized Building System (IBS) is one of the approaches that had been introduced as an alternative to conventional building method where it becomes the new strategy of enhancing the sustainable construction in current industries while spearheading a huge advancement of benefits with green constructions into the existing industries. The IBS approach is actively promoted through several strategies and incentives as an alternative to conventional building methods. Extensive uptakes of modern Information Communication Technology (ICT) applications are able to support the different IBS processes for effective production. However, it is argued that ICT uptake at the organisational level is still in its infancy. This raises the importance to identify critical inhibitors which are inhibing the effective uptake of ICT in the IBS production management process. Critical inhibitors to ICT uptake were identified through questionnaire survey with the IBS industry stakeholders. The mean index and critical t-values are generated with the use of the quantitative tool, Statistical Package for Social Sciences (SPSS). The top ten priority ranked inhibitors reflect the Cost, People and Process elements to ICT uptake. High costs in acquiring the technologies and resistance to change were some main concerns from the findings.

Mixing rates and vertical heat fluxes north of Svalbard from Arctic winter to spring

NASA Astrophysics Data System (ADS)

Meyer, Amelie; Fer, Ilker; Sundfjord, Arild; Peterson, Algot K.

2017-06-01

Mixing and heat flux rates collected in the Eurasian Basin north of Svalbard during the N-ICE2015 drift expedition are presented. The observations cover the deep Nansen Basin, the Svalbard continental slope, and the shallow Yermak Plateau from winter to summer. Mean quiescent winter heat flux values in the Nansen Basin are 2 W m-2 at the ice-ocean interface, 3 W m-2 in the pycnocline, and 1 W m-2 below the pycnocline. Large heat fluxes exceeding 300 W m-2 are observed in the late spring close to the surface over the Yermak Plateau. The data consisting of 588 microstructure profiles and 50 days of high-resolution under-ice turbulence measurements are used to quantify the impact of several forcing factors on turbulent dissipation and heat flux rates. Wind forcing increases turbulent dissipation seven times in the upper 50 m, and doubles heat fluxes at the ice-ocean interface. The presence of warm Atlantic Water close to the surface increases the temperature gradient in the water column, leading to enhanced heat flux rates within the pycnocline. Steep topography consistently enhances dissipation rates by a factor of four and episodically increases heat flux at depth. It is, however, the combination of storms and shallow Atlantic Water that leads to the highest heat flux rates observed: ice-ocean interface heat fluxes average 100 W m-2 during peak events and are associated with rapid basal sea ice melt, reaching 25 cm/d.

Effect of phase change material on the heat transfer rate of different building materials

NASA Astrophysics Data System (ADS)

Hasan, Mushfiq; Alam, Shahnur; Ahmed, Dewan Hasan

2017-12-01

Phase change material (PCM) is widely known as latent heat storage. A comprehensive study is carried out to investigate the effect of PCM on heat transfer rate of building materials. Paraffin is used as PCM along with different conventional building materials to investigate the heat transfer rate from the heated region to the cold region. PCM is placed along with the three different types of building materials like plaster which is well know building material in urban areas and wood and straw which are commonly used in rural areas for roofing as well as wall panel material and investigated the heat transfer rate. An experimental setup was constructed with number of rectangular shape aluminum detachable casing (as cavity) and placed side by side. Series of rectangular cavity filled with convent ional building materials and PCM and these were placed in between two chambers filled with water at different temperature. Building materials and PCM were placed in different cavities with different combinations and investigated the heat transfer rate. The results show that using the PCM along with other building materials can be used to maintain lower temperature at the inner wall and chamber of the cold region. Moreover, the placement or orientation of the building materials and PCM make significant contribution to heat transfer rate from the heated zone to the cold zone.

Effect of heating rate on thermoluminescence output of LiF: Mg, Ti (TLD-100) in dosimetric applications

NASA Astrophysics Data System (ADS)

Singh, Ranjit; Kainth, Harpreet Singh

2018-07-01

The luminiscence characteristics of thermoluminscence dosimeter LiF: Mg, Ti (TLD-100) irradiated to X-rays from 6 MV linac have been studied for wide range of 2-50 K/s readout linear heating rates. The reproducibility of glow curves for TLDs is found to be better at lower heating rates and depreciate at higher heating rates. The glow curve spectra were analysed using deconvolution procedure based on general-order kinetics. Shift in the peak maximum temperature per unit rise in heating rate for various peaks were found to decrease with heating rate. The TLDs irradiated with same dose exhibit decreasing TL counts with increase in the heating rate, which indicate the thermal quenching effect in TLD-100. The value of activation energy for each peak within the glow curve increases with heating rate. Calibration curves plotted for the dose range 0.4-1020 cGy exhibit decreasing slope with increasing readout heating rate. Corrections for temperature lag between the heating element and the dosimeter, and the effective heating rate (βeff) across the sample estimated using formulation proposed by Kitis and Tuyn and are found to be fairly applicable.

Antibodies to CBir1 are Associated with Glycogen Storage Disease Type Ib

PubMed Central

Davis, Michael K.; Valentine, John F.; Weinstein, David A.; Polyak, Steven

2009-01-01

Objectives Glycogen storage disease (GSD) type Ib is a congenital disorder of glycogen metabolism that is associated with neutropenia, neutrophil and monocyte dysfunction, and an inflammatory bowel disease (IBD) that mimics a Crohn's disease phenotype. The enteric microflora is implicated in the pathogenesis of IBD; however, its role in the development of GSD-associated IBD is unknown. Antibody reactivity to Saccharomyces cerevisiae antibodies (ASCA), Escherichia coli outer membrane porin C (anti-OmpC) and bacterial flagellin (anti-CBir1) have been associated with Crohn's disease in the general population, but they have an undetermined association in children and adults with GSD-Ib. Our goal was to examine the association of ASCA, anti-OmpC and anti-CBir1 with the clinical features of GSD-Ib enterocolitis. Methods A retrospective review identified 19 GSD-Ib patients with or without a known diagnosis of enterocolitis. Radiographic, endoscopic and serologic data were collected and assays for ASCA, anti-OmpC, and anti-CBir1 obtained. Results Seven patients had combined radiographic, endoscopic, and histological evidence of intestinal inflammation; the majority had ileocolonic involvement. Seventeen of 19 (89%) patients had elevated anti-CBir1 levels (6/7 in the IBD group and 11/12 in the no clinical evidence of IBD group). Thirteen of 19 (68%) had elevated anti-OmpC levels (5/7 in the IBD group and 8/12 in the no clinical evidence of IBD group). Eleven of 19 (58%) patients had elevated ASCA IgA levels (4/7 in the IBD group and 7/12 in the no clinical evidence of IBD group). Conclusion Nearly all of the GSD type Ib patients had elevated anti-CBir1 levels. The antibody did not differentiate those with and without a diagnosis of GSD-Ib-associated IBD. Seroreactivity to flagellin may represent immune dysfunction rather than active enterocolitis in this patient population. Long-term follow-up of the group without known IBD is required to determine if these antibodies can

Solid motor aft closure insulation erosion. [heat flux correlation for rate analysis

NASA Technical Reports Server (NTRS)

Stampfl, E.; Landsbaum, E. M.

1973-01-01

The erosion rate of aft closure insulation in a number of large solid propellant motors was empirically analyzed by correlating the average ablation rate with a number of variables that had previously been demonstrated to affect heat flux. The main correlating parameter was a heat flux based on the simplified Bartz heat transfer coefficient corrected for two-dimensional effects. A multiplying group contained terms related to port-to-throat ratio, local wall angle, grain geometry and nozzle cant angle. The resulting equation gave a good correlation and is a useful design tool.

How the Change in IBS Criteria From Rome III to Rome IV Impacts on Clinical Characteristics and Key Pathophysiological Factors.

PubMed

Aziz, Imran; Törnblom, Hans; Palsson, Olafur S; Whitehead, William E; Simrén, Magnus

2018-06-08

The diagnostic criteria for irritable bowel syndrome (IBS) have recently been updated from Rome III to Rome IV. Whereas in Rome III a diagnosis of IBS entailed chronic abdominal pain or discomfort at least 3 days per month, in Rome IV the term discomfort has been removed and the frequency of abdominal pain increased to at least 1 day per week. We examined how this change in IBS criteria impacts on clinical characteristics and pathophysiological factors. A total of 542 Swedish subjects with Rome III IBS completed a baseline questionnaire enquiring for the number of abdominal pain days in the last 10 days; this was subsequently used as a surrogate marker to identify Rome IV IBS, in that (a) those with 0 or 1 day of pain were classed as Rome IV-negative, and (b) those with ≥2 days of pain were classed as Rome IV-positive. Comparisons were made between Rome IV-positive and -negative IBS groups for demographics, IBS subtype, gastrointestinal and psychological symptoms, somatisation, fatigue, disease-specific quality of life, rectal sensitivity, and oro-anal transit time. Overall, 85% of Rome III IBS patients fulfilled the Rome IV criteria for IBS, but 15% did not. Rome IV-positive subjects were significantly more likely to be female, have poorer quality of life, greater pain severity, bloating, somatisation, fatigue, and rectal sensitivity than Rome IV-negative subjects. There were no differences in severity of anxiety or depression, IBS subtypes, bowel habit dissatisfaction, or oro-anal transit time. Finally, increasing number of pain days correlated positively with symptoms and visceral hypersensitivity. Most Rome III-positive IBS patients seeking healthcare fulfil the Rome IV IBS criteria. They constitute a more severe group than those who lose their IBS diagnosis.

Heating rates in collisionally opaque alkali-metal atom traps: Role of secondary collisions

NASA Astrophysics Data System (ADS)

Beijerinck, H. C. W.

2000-12-01

Grazing collisions with background gas are the major cause of trap loss and trap heating in atom traps. To first order, these effects do not depend on the trap density. In collisionally opaque trapped atom clouds, however, scattered atoms with an energy E larger than the effective trap depth Eeff, which are destined to escape from the atom cloud, will have a finite probability for a secondary collision. This results in a contribution to the heating rate that depends on the column density of the trapped atoms, i.e., the product of density and characteristic size of the trap. For alkali-metal atom traps, secondary collisions are quite important due to the strong long-range interaction with like atoms. We derive a simple analytical expression for the secondary heating rate, showing a dependency proportional to E1/2eff. When extrapolating to a vanishing column density, only primary collisions with the background gas will contribute to the heating rate. This contribution is rather small, due to the weak long-range interaction of the usual background gas species in an ultrahigh-vacuum system-He, Ne, or Ar-with the trapped alkali-metal atoms. We conclude that the transition between trap-loss collisions and heating collisions is determined by a cutoff energy 200 μK<=Eeff<=400 μK, much smaller than the actual trap depth E in most magnetic traps. Atoms with an energy Eeffheating rates for the alkali-metal atoms Li through Cs as a function of the effective trap depth, the column density of the trap, and the species in the background gas. The predictions of our model are in good agreement with the experimental data of Myatt for heating rates in high-density 87Rb-atom magnetic traps at JILA, including the effect of the rf shield and the composition of the background gas. It is shown that collisions with atoms from the Oort

The International Baccalaureate (IB) Programme: An International Gateway to Higher Education and Beyond

ERIC Educational Resources Information Center

Hill, Ian; Saxton, Susan

2014-01-01

The aim of this article is to present the International Baccalaureate (IB) Programme and briefly outline its core components, followed by a review of what authoritative reports identify as skills for the future, esteemed by universities and the job market. There is a striking match between these skills and IB outcomes; thus, DP graduates perform…

The ties that bind: perceived social support, stress, and IBS in severely affected patients

PubMed Central

LACKNER, J. M.; BRASEL, A. M.; QUIGLEY, B M.; KEEFER, L.; KRASNER, S. S.; POWELL, C.; KATZ, L. A.; SITRIN, M. D.

2016-01-01

Background This study assessed the association between social support and the severity of irritable bowel syndrome (IBS) symptoms in a sample of severely affected IBS patients recruited to an NIH-funded clinical trial. In addition, we examined if the effects of social support on IBS pain are mediated through the effects on stress. Methods Subjects were 105 Rome II diagnosed IBS patients (F = 85%) who completed seven questionnaires which were collected as part of a pretreatment baseline assessment. Key Results Partial correlations were conducted to clarify the relationships between social support and clinically relevant variables with baseline levels of psychopathology, holding constant number of comorbid medical diseases, age, gender, marital status, ethnicity, and education. Analyses indicated that social support was inversely related to IBS symptom severity. Social support was positively related with less severe pain. A similar pattern of data was found for perceived stress but not quality of life impairment. Regression analyses examined if the effects of social support on pain are mediated by stress. The effects of social support on bodily pain were mediated by stress such that the greater the social support the less stress and the less pain. This effect did not hold for symptom severity, quality of life, or psychological distress. Conclusions & Inferences This study links the perceived adequacy of social support to the global severity of symptoms of IBS and its cardinal symptom (pain). It also suggests that the mechanism by which social support alleviates pain is through a reduction in stress levels. PMID:20465594

With World Growing Smaller, IB Gets Big

ERIC Educational Resources Information Center

Cech, Scott J.

2007-01-01

The perception that the Geneva, Switzerland-based International Baccalaureate Organization's academic programs offer just what American students need in today's more globally competitive environment seems to be catching on. After decades of obscurity and slow expansion, the pace of growth in IB--including courses of study for the primary and…

Characterization of Tn6238 with a New Allele of aac(6′)-Ib-cr

PubMed Central

Quiroga, María P.; Orman, Betina; Errecalde, Laura; Kaufman, Sara

2015-01-01

Here, we report that the genetic structure of Tn1331 remained conserved in Argentina from 1989 to 2013 (72 of 73 isolates), with the exception being the plasmid-borne Tn1331-like transposon Tn6238 containing a new aac(6′)-Ib-cr allele recovered from a colistin-resistant Klebsiella pneumoniae clinical isolate. A bioinformatic analysis of aac(6′)-Ib-like gene cassettes suggests that this new aac(6′)-Ib-cr allele emerged through mutation or homologous recombination in the Tn1331 genetic platform. Tn6238 is a novel platform for the dissemination of aminoglycoside and fluoroquinolone resistance determinants. PMID:25691640

Gastrointestinal permeability (GIPerm) is increased in family members of children with functional abdominal pain (FAP) and irritable bowel syndrome (IBS)

USDA-ARS?s Scientific Manuscript database

Increased GIPerm has been described in children with FAP/IBS and adults with IBS. We sought to determine if baseline GIPerm is increased and if ibuprofen induces a greater increase in GIPerm in parents and siblings of children with FAP/IBS vs. control families without children with FAP/IBS. Site spe...

Artificial Neural Networks-Based Software for Measuring Heat Collection Rate and Heat Loss Coefficient of Water-in-Glass Evacuated Tube Solar Water Heaters.

PubMed

Liu, Zhijian; Liu, Kejun; Li, Hao; Zhang, Xinyu; Jin, Guangya; Cheng, Kewei

2015-01-01

Measurements of heat collection rate and heat loss coefficient are crucial for the evaluation of in service water-in-glass evacuated tube solar water heaters. However, conventional measurement requires expensive detection devices and undergoes a series of complicated procedures. To simplify the measurement and reduce the cost, software based on artificial neural networks for measuring heat collection rate and heat loss coefficient of water-in-glass evacuated tube solar water heaters was developed. Using multilayer feed-forward neural networks with back-propagation algorithm, we developed and tested our program on the basis of 915 measured samples of water-in-glass evacuated tube solar water heaters. This artificial neural networks-based software program automatically obtained accurate heat collection rate and heat loss coefficient using simply "portable test instruments" acquired parameters, including tube length, number of tubes, tube center distance, heat water mass in tank, collector area, angle between tubes and ground and final temperature. Our results show that this software (on both personal computer and Android platforms) is efficient and convenient to predict the heat collection rate and heat loss coefficient due to it slow root mean square errors in prediction. The software now can be downloaded from http://t.cn/RLPKF08.

Space Shuttle Orbiter flight heating rate measurement sensitivity to thermal protection system uncertainties

NASA Technical Reports Server (NTRS)

Bradley, P. F.; Throckmorton, D. A.

1981-01-01

A study was completed to determine the sensitivity of computed convective heating rates to uncertainties in the thermal protection system thermal model. Those parameters considered were: density, thermal conductivity, and specific heat of both the reusable surface insulation and its coating; coating thickness and emittance; and temperature measurement uncertainty. The assessment used a modified version of the computer program to calculate heating rates from temperature time histories. The original version of the program solves the direct one dimensional heating problem and this modified version of The program is set up to solve the inverse problem. The modified program was used in thermocouple data reduction for shuttle flight data. Both nominal thermal models and altered thermal models were used to determine the necessity for accurate knowledge of thermal protection system's material thermal properties. For many thermal properties, the sensitivity (inaccuracies created in the calculation of convective heating rate by an altered property) was very low.

Identification of a small molecule inhibitor of the aminoglycoside 6'-N-acetyltransferase type Ib [AAC(6')-Ib] using mixture-based combinatorial libraries.

PubMed

Tran, Tung; Chiem, Kevin; Jani, Saumya; Arivett, Brock A; Lin, David L; Lad, Rupali; Jimenez, Verónica; Farone, Mary B; Debevec, Ginamarie; Santos, Radleigh; Giulianotti, Marc; Pinilla, Clemencia; Tolmasky, Marcelo E

2018-05-01

The aminoglycoside, 6'-N-acetyltransferase type Ib [AAC(6')-Ib] is the most widely distributed enzyme among AAC(6')-I-producing Gram-negative pathogens and confers resistance to clinically relevant aminoglycosides, including amikacin. This enzyme is therefore an ideal target for enzymatic inhibitors that could overcome resistance to aminoglycosides. The search for inhibitors was carried out using mixture-based combinatorial libraries, the scaffold ranking approach, and the positional scanning strategy. A library with high inhibitory activity had pyrrolidine pentamine scaffold and was selected for further analysis. This library contained 738,192 compounds with functionalities derived from 26 different amino acids (R1, R2 and R3) and 42 different carboxylic acids (R4) in four R-group functionalities. The most active compounds all contained S-phenyl (R1 and R3) and S-hydromethyl (R2) functionalities at three locations and differed at the R4 position. The compound containing 3-phenylbutyl at R4 (compound 206) was a robust enzymatic inhibitor in vitro, in combination with amikacin it potentiated the inhibition of growth of three resistant bacteria in culture, and it improved survival when used as treatment of Galleria mellonella infected with aac(6')-Ib-harboring Klebsiella pneumoniae and Acinetobacter baumannii strains. Copyright © 2018 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.

[Effect of Tongxie Yaofang on endogenous metabolites in serum of IBS model rats].

PubMed

Li, Kai; Kuang, Hai-Xue; Yin, Yue; Zhang, Jie-Yu; Wang, Zhi; Zhang, Qiu-Yue; Wang, Jian-Wei

2017-03-01

To evaluate the effect of Tongxie Yaofang on cardiac endogenous metabolism in irritable bowel syndrome(IBS) rats by using metabolomics method, find its potential biomarkers, analyze the metabolic pathways, and explore the pharmacological effects, mechanisms of action and syndrome essence of syndrome model. Forty Wistar rats were used to establish IBS models, and then randomly divided into four groups： model control group and Tongxie Yaofang treatment groups (high, medium, low dose). Another 10 rats were used as normal group. The rats in Tongxie Yaofang-treated(low, medium and high dose) groups were orally administrated with Tongxie Yaofang extracts once a day for 2 weeks, respondingly with the doses of 0.203,0.406,0.812 g•mL⁻¹. The rats in normal group and model control group were given with equal volume of saline once a day for 2 weeks. On the 0 and 15th days, serum was collected and each sample extract was analyzed by UPLC-Q-TOF-MS. Eight potential biomarkers were identified and 8 major metabolic pathways were found to be related with IBS diseases neurotransmitter metabolism, inflammatory immunity, brain function and energy metabolism, etc. Tongxie Yaofang had certain pharmacological effects on IBS, and its mechanism may be related to serotonergic synapse, tryptophan metabolism, cysteine and methionine metabolism, glycerophospholipid metabolism, nicotinate and nicotinamide metabolism and so on, which might be the biological basis of IBS liver-spleen deficiency syndrome. Copyright© by the Chinese Pharmaceutical Association.

The Futility of Propensity Score Methods in a Statewide Study of International Baccalaureate (IB)

ERIC Educational Resources Information Center

May, Henry; Rodriguez, Awilda; Sirinides, Philip M.; Perna, Laura W.; Yee, April; Ransom, Tafaya

2014-01-01

With the goal of increasing students' academic readiness for college, high schools in the United States are increasingly offering "credit-based transition programs," including International Baccalaureate (IB), Advanced Placement (AP), and dual enrollment. Existing research points to the promise of IB, AP, and other credit-based…

Travel Tips Help IBS Sufferers Enjoy Their Vacations

MedlinePlus

... can feel more in control when traveling." IFFGD's travel tips include: Allow enough time in the morning to get to the airport ... Heartache 2004-0929 Norton Honored 2004-0525 IBS Travel Tips ... Real World 2001-1119 Heartburn or Heart Attack Commentary ...

Comparison of medical costs generated by IBS patients in primary and secondary care in the Netherlands.

PubMed

Flik, Carla E; Laan, Wijnand; Smout, André J P M; Weusten, Bas L A M; de Wit, Niek J

2015-11-26

Irritable Bowel Syndrome (IBS) is a functional somatic syndrome characterized by patterns of persistent bodily complaints for which a thorough diagnostic workup does not reveal adequate explanatory structural pathology. Detailed insight into disease-specific health-care costs is critical because it co-determines the societal impact of the disease, enables the assessment of cost-effectiveness of existing and new treatments, and facilitates choices in treatment policy. In the present study the aim was, to compare the costs and magnitude of healthcare consumption for patients diagnosed with Irritable Bowel Syndrome (IBS) in primary and secondary care, compare these costs with the average health care expenditure for patients without IBS and describe these costs in further detail. Reimbursement data for patients diagnosed with IBS by a general practitioner (GP) or specialist between 2006 and 2009 were extracted from a healthcare insurance company and compared to an age and gender matched control group of patients without IBS. Using a case-control design, direct medical costs for GP consultations, specialist care and medication prescriptions were calculated. Data of 326 primary care and 9274 secondary care IBS patients were included in the analysis. For primary care patients, the mean total annual health care costs for the three years after diagnosis compared to the three years before diagnosis, increased with 486 Euro after IBS was diagnosed, whereas for secondary care patients, these costs increased with 2328 Euro. Total health care costs remained higher in the three years after the initial diagnosis when the patient is treated in secondary care, compared to primary care. This increase was significant for hospital specialist costs and medications, but not for GP contacts. For controls, there was no significant difference in mean total annual health costs in the three years before and the three years after the diagnosis and also no significant difference in cost

Modality-specific peripheral antinociceptive effects of μ-opioid agonists on heat and mechanical stimuli: Contribution of sigma-1 receptors.

PubMed

Montilla-García, Ángeles; Perazzoli, Gloria; Tejada, Miguel Á; González-Cano, Rafael; Sánchez-Fernández, Cristina; Cobos, Enrique J; Baeyens, José M

2018-06-01

Morphine induces peripherally μ-opioid-mediated antinociception to heat but not to mechanical stimulation. Peripheral sigma-1 receptors tonically inhibit μ-opioid antinociception to mechanical stimuli, but it is unknown whether they modulate μ-opioid heat antinociception. We hypothesized that sigma-1 receptors might play a role in the modality-specific peripheral antinociceptive effects of morphine and other clinically relevant μ-opioid agonists. Mechanical nociception was assessed in mice with the paw pressure test (450 g), and heat nociception with the unilateral hot plate (55 °C) test. Local peripheral (intraplantar) administration of morphine, buprenorphine or oxycodone did not induce antinociception to mechanical stimulation but had dose-dependent antinociceptive effects on heat stimuli. Local sigma-1 antagonism unmasked peripheral antinociception by μ-opioid agonists to mechanical stimuli, but did not modify their effects on heat stimulation. TRPV1+ and IB4+ cells are segregated populations of small neurons in the dorsal root ganglia (DRG) and the density of sigma-1 receptors was higher in IB4+ cells than in the rest of small nociceptive neurons. The in vivo ablation of TRPV1-expressing neurons with resiniferatoxin did not alter IB4+ neurons in the DRG, mechanical nociception, or the effects of sigma-1 antagonism on local morphine antinociception in this type of stimulus. However, it impaired the responses to heat stimuli and the effect of local morphine on heat nociception. In conclusion, peripheral opioid antinociception to mechanical stimuli is limited by sigma-1 tonic inhibitory actions, whereas peripheral opioid antinociception to heat stimuli (produced in TRPV1-expressing neurons) is not. Therefore, sigma-1 receptors contribute to the modality-specific peripheral effects of opioid analgesics. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Streptococcus agalactiae serotype Ib as an agent of meningitis in two adult nonpregnant women.

PubMed

Martins, E R; Florindo, C; Martins, F; Aldir, I; Borrego, M J; Brum, L; Ramirez, M; Melo-Cristino, J

2007-11-01

Two temporally and geographically clustered cases of meningitis caused by Streptococcus agalactiae expressing the infrequent Ib serotype are reported. Characterization by pulsed-field gel electrophoresis and multilocus sequence typing revealed that the isolates were identical and represented the widely distributed ST10/ST8 lineage associated with serotype Ib.

Does Education Have Any Influence on Symptom Score of IBS Patients: A Randomized Controlled Study.

PubMed

Sarkar, S K; Tarafder, A J; Chowdhury, M; Alam, M S; Mohsin, M

2016-04-01

Despite much research, the pathophysiology of IBS remains poorly understood. So it is very difficult to treat. There is no standard treatment for IBS. Because IBS symptoms can be elicited or exacerbated by diet and stress, this suggests that patient education regarding his or her illness might be beneficial to patients in managing their symptoms. This study was done to see the short term effects of outpatient education in relation to change of symptom score in IBS patients. This is a prospective randomized comparative study. In this study a total of 80 patients were included. Forty patients were given only pharmacological management with Mebevarine hydrochloride 135mg thrice daily half an hour before meal and Amitryptline 10mg at night for six months and another forty were given education in addition to the same pharmacological treatment. In both the study group [medical management only versus medical management with education] changes of symptoms and quality of life of patients of IBS were assessed by using previously used, specially designed symptoms scoring system and a validated IBS-QOL instrument. There was no significant difference in severity of symptoms between only drug treatment group (118.973) and education plus drug treatment group (119.57) before treatment. The difference of improvement between the education group and without education group was not statistically significant (P>0.05), though the subsidence of pain in both the group before and after treatment was statistically significant (P<0.01).

Relationships of abdominal pain, reports to visceral and temperature pain sensitivity, conditioned pain modulation, and heart rate variability in irritable bowel syndrome.

PubMed

Jarrett, M E; Han, C J; Cain, K C; Burr, R L; Shulman, R J; Barney, P G; Naliboff, B D; Zia, J; Heitkemper, M M

2016-07-01

Irritable bowel syndrome (IBS) is a heterogeneous condition with a number of pathophysiological mechanisms that appear to contribute to symptom chronicity. One of these is altered pain sensitivity. Women between ages 18-45 were recruited the community. Of those enrolled, 56 had IBS and 36 were healthy control (HC) women. Participants completed questionnaires, kept a 4-week symptom diary and had a 12-h Holter placed to assess nighttime heart rate variability including high frequency power (HF), low frequency power (LF), and total power (TP). At mid-follicular phase approximately 80% of women completed a thermal pain sensitivity test with conditioned pain modulation and visceral pain sensitivity using a water load symptom provocation (WLSP) test. As expected, daily abdominal pain was significantly higher in the IBS compared to HC group. There were no differences between the bowel pattern subgroups (IBS-diarrhea [IBS-D], IBS-constipation plus mixed [IBS-CM]). Thermal pain sensitivity did not differ between the IBS and the HC groups, but was significantly higher in the IBS-CM group than the IBS-D group. In the WLSP test, the IBS group experienced significantly more symptom distress than HCs and the IBS-CM group was higher than the IBS-D group. Heart rate variability indicators did not differ between the groups or IBS subgroups. Daily abdominal pain was positively correlated with LF and TP in the IBS group. Despite similar levels of abdominal pain in IBS, the IBS-CM group demonstrated greater sensitivity to both thermal and visceral testing procedures. © 2016 John Wiley & Sons Ltd.

Impact of heat release on strain rate field in turbulent premixed Bunsen flames

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

Coriton, Bruno Rene Leon; Frank, Jonathan H.

2016-08-10

The effects of combustion on the strain rate field are investigated in turbulent premixed CH 4/air Bunsen flames using simultaneous tomographic PIV and OH LIF measurements. Tomographic PIV provides three-dimensional velocity measurements, from which the complete strain rate tensor is determined. The OH LIF measurements are used to determine the position of the flame surface and the flame-normal orientation within the imaging plane. This combination of diagnostic techniques enables quantification of divergence as well as flame-normal and tangential strain rates, which are otherwise biased using only planar measurements. Measurements are compared in three lean-to-stoichiometric flames that have different amounts ofmore » heat release and Damköhler numbers greater than unity. The effects of heat release on the principal strain rates and their alignment relative to the local flame normal are analyzed. The extensive strain rate preferentially aligns with the flame normal in the reaction zone, which has been indicated by previous studies. The strength of this alignment increases with increasing heat release and, as a result, the flame-normal strain rate becomes highly extensive. These effects are associated with the gas expansion normal to the flame surface, which is largest for the stoichiometric flame. In the preheat zone, the compressive strain rate has a tendency to align with the flame normal. Away from the flame front, the flame – strain rate alignment is arbitrary in both the reactants and products. The flame-tangential strain rate is on average positive across the flame front, and therefore the turbulent strain rate field contributes to the enhancement of scalar gradients as in passive scalar turbulence. As a result, increases in heat release result in larger positive values of the divergence as well as flame-normal and tangential strain rates, the tangential strain rate has a weaker dependence on heat release than the flame-normal strain rate and the

Fear of GI symptoms has an important impact on quality of life in patients with moderate-to-severe IBS.

PubMed

Lackner, Jeffrey M; Gudleski, Gregory D; Ma, Chang-Xing; Dewanwala, Akriti; Naliboff, Bruce

2014-11-01

Because irritable bowel syndrome (IBS) is a functional medical condition for which there is no curative therapy, treatment goals emphasize relieving gastrointestinal (GI) symptoms and optimizing the quality of life (QOL). This study sought to characterize the magnitude of the associations between QOL impairment, fear of IBS symptoms, and confounding variables. Subjects included 234 Rome III-diagnosed IBS patients (mean age, 41 years, 79%, female) without comorbid organic GI disease who were referred to two specialty care clinics of an National Institutes of Health trial for IBS. Subjects completed a testing battery that included the IBS-specific QOL (IBS-QOL), SF-12 (generic QOL), the UCLA GI Symptom Severity Scale, the Visceral Sensitivity Index, Trait Anxiety Inventory, and Brief Symptom Inventory. Multiple linear regression was used to develop a model for predicting QOL. Data supported an overall model that included sociodemographic, clinical (e.g., current severity of GI symptoms), and psychosocial (e.g., fear of GI symptoms, distress, neuroticism) variables, accounting for 48.7% of the variance in IBS-QOL (F=15.1, P <0.01). GI symptom fear was the most robust predictor of IBS-QOL (β=-0.45 P <0.01), accounting for 14.4% of the total variance. Patients' fear that GI symptoms have aversive consequences, is a predictor of QOL impairment that cannot be fully explained by the severity of their GI symptoms, overall emotional well-being, neurotic personality style, or other clinical features of IBS. An understanding of the unique impact that GI symptom fears have on QOL can inform treatment planning and help gastroenterologists to better manage more severe IBS patients seen in tertiary care clinics.

Pharmacokinetic properties of IB1001, an investigational recombinant factor IX, in patients with haemophilia B: repeat pharmacokinetic evaluation and sialylation analysis.

PubMed

Martinowitz, U; Shapiro, A; Quon, D V; Escobar, M; Kempton, C; Collins, P W; Chowdary, P; Makris, M; Mannucci, P M; Morfini, M; Valentino, L A; Gomperts, E; Lee, M

2012-11-01

IB1001 trenacog alfa is an investigational recombinant factor IX (FIX) for the treatment and prevention of bleeding in individuals with haemophilia B. To compare the pharmacokinetics (PK) of IB1001 with nonacog alfa in individuals with haemophilia B and to assess the relationship between sialylation and PK of IB1001 (NCT00768287). A randomized, double-blind, non-inferiority, cross-over study conducted in participants aged ≥ 12 years weighing ≥ 40 kg, with severe or moderately severe haemophilia B (FIX activity ≤ 2 IU dL (-1) ). PK parameters were derived using observed FIX concentration levels and actual PK sampling times, and repeated in a subset of participants who had received IB1001 prophylaxis for 4-18 months. A retrospective analysis was conducted in subgroups according to the sialylation levels of IB1001 (50.8, 57.8-59.0%, or 71.7%). In the 32 adolescent and adult males evaluated, there were no clinically meaningful differences in PK parameters between those receiving IB1001 75 IU kg(-1) or nonacog alfa. The lower limit of the one-sided 95% confidence interval for the ratio of AUC(0-t) and AUC(0-∞) (IB1001/nonacog alfa) was 0.90, establishing non-inferiority. Terminal phase half-lives were similar (29.7 ± 18.2 h for IB1001 and 33.4 ± 21.2 h for nonacog alfa). The PK results were stable for up to 18 months of IB1001 exposure; the impact of sialylation levels was not clinically meaningful. There were no clinically meaningful PK differences between IB1001 and nonacog alfa. IB1001 was well tolerated and without safety concerns. The non-inferiority of IB1001 to nonacog alfa supports IB1001 becoming a useful alternative recombinant agent for the management of haemophilia B. © 2012 Blackwell Publishing Ltd.

Blastocystis specific serum immunoglobulin in patients with irritable bowel syndrome (IBS) versus healthy controls.

PubMed

Nagel, Robyn; Traub, Rebecca J; Kwan, Marcella M S; Bielefeldt-Ohmann, Helle

2015-09-15

Blastocystis species are common enteric human parasites and carriage has been linked to Irritable Bowel Syndrome (IBS), particularly diarrhoea-predominant IBS. The spectrum of immune reactivity to Blastocystis proteins has been reported previously in symptomatic patients. We investigated differences in serum immunoglobulin profiles between patients with IBS, both positive and negative for Blastocystis carriage, and healthy controls (HC). Forty diarrhoea-predominant IBS patients (26 patients positive for Blastocystis sp., 14 negative patients) and forty HC (24 positive, 16 Blastocystis-negative) were enrolled. Age, gender, ethnicity and serum immunoglobulin A (IgA) levels were recorded and faecal specimens were analysed using smear, culture and polymerase chain reaction amplification of ribosomal DNA. Sera were tested in Western blots and the reactivities compared to known targets using monoclonal antibodies Blastofluor® (Blastocystis specific antibody), MAb1D5 (cytopathicto Blastocystis cells), anti-promatrix metalloprotease-9 (anti-MMP-9) and SDS-PAGE zymograms. Levels of serum IgA were significantly lower in Blastocystis carriers (p < 0.001) but had no relationship to symptoms. Western blots demonstrated serum IgG antibodies specific for Blastocystis proteins of 17,27,37,50,60-65, 75-90, 95-105 and 150 kDa MW. Reactivity to the 27, 50 and 75-95 kDa proteins were found more frequently in the IBS group compared to the HC's (p < 0.001) and correlation was greater for Blastocystis-positive IBS patients (p < 0.001) than for negative IBS patients (p < 0.05). MAb1D5 reacted with proteins of 27 and 100 kDa, and anti-MMP-9 with 27, 50 and 75-100 kDa proteins. Bands were seen in zymograms around 100 kDa. Low serum IgA levels are associated with Blastocystis carriage. All IBS patients were more likely to demonstrate reactivity with Blastocystis proteins of 27 kDa (likely a cysteine protease), 50 and 75-95 kDa MW compared to HC. The presence of

Long-term clincopathological characteristics of alpacas naturally infected with bovine viral diarrhea virus type Ib

USDA-ARS?s Scientific Manuscript database

Background: Substantial bovine viral diarrhea virus (BVDV)-related production losses in North American alpaca herds have been associated with BVDV type Ib infection. Objectives: To classify and differentiate the long-term clinicopathological characteristics of BVDV type Ib infection of alpaca crias,...

Standby Rates for Combined Heat and Power Systems

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

Sedano, Richard; Selecky, James; Iverson, Kathryn

2014-02-01

Improvements in technology, low natural gas prices, and more flexible and positive attitudes in government and utilities are making distributed generation more viable. With more distributed generation, notably combined heat and power, comes an increase in the importance of standby rates, the cost of services utilities provide when customer generation is not operating or is insufficient to meet full load. This work looks at existing utility standby tariffs in five states. It uses these existing rates and terms to showcase practices that demonstrate a sound application of regulatory principles and ones that do not. The paper also addresses areas formore » improvement in standby rates.« less

Suggestive association of major histocompatibility IB genetic markers with resistance to bacterial cold water disease in rainbow trout (Oncorhynchus mykiss).

PubMed

Johnson, Nathan A; Vallejo, Roger L; Silverstein, Jeffrey T; Welch, Timothy J; Wiens, Gregory D; Hallerman, Eric M; Palti, Yniv

2008-01-01

Genes within the major histocompatibility complex (MHC) are important for both innate and adaptive immune responses in mammals; however, much less is known regarding their contribution in teleost fishes. We examined the involvement of four major histocompatibility (MH) genomic regions in rainbow trout in resistance to the causative agent of bacterial coldwater disease (BCWD), Flavobacterium psychrophilum. Fish from the 2005 NCCCWA brood-year (71 full-sib families) were challenged with F. psychrophilum strain CSF 259-93. The overall mortality rate was 70%, with large variation in mortality between families. Disease resistance was quantified as post-challenge days to death. Phenotypic variation and additive genetic variation were estimated using mixed models of survival analysis. To examine association, eight microsatellite markers were isolated from MH gene-containing BAC clones and mapped onto the rainbow trout genetic linkage map. The parents and grandparents of the 2005 brood-year families were genotyped with these eight markers and another two markers tightly linked to the MH-IB region to assess the extent of linkage disequilibrium (LD) of MH genomic regions MH-IA, MH-IB, TAP1, and MH-II with survival post-challenge. MH-IB and MH-II markers were linked to BCWD survivability when data were analyzed by family. Tests for disease association at the population level substantiated the involvement of MH-IB, but not MH-II, with disease resistance. The impact of selective breeding for disease resistance on MH sequence variation is discussed in the context of aquaculture production.

IB-LBM study on cell sorting by pinched flow fractionation.

PubMed

Ma, Jingtao; Xu, Yuanqing; Tian, Fangbao; Tang, Xiaoying

2014-01-01

Separation of two categories of cells in pinched flow fractionation(PFF) device is simulated by employing IB-LBM. The separation performances at low Reynolds number (about 1) under different pinched segment widths, flow ratios, cell features, and distances between neighboring cells are studied and the results are compared with those predicted by the empirical formula. The simulation indicates that the diluent flow rate should approximate to or more than the flow rate of particle solution in order to get a relatively ideal separation performance. The discrepancy of outflow position between numerical simulation and the empirical prediction enlarges, when the cells become more flexible. Too short distance between two neighboring cells could lead to cell banding which would result in incomplete separation, and the relative position of two neighboring cells influences the banding of cells. The present study will probably provide some new applications of PFF, and make some suggestions on the design of PFF devices.

Influence of heating rate on the condensational instability. [in outer layers of solar atmosphere

NASA Technical Reports Server (NTRS)

Dahlburg, R. B.; Mariska, J. T.

1988-01-01

Analysis and numerical simulation are used to determine the effect that various heating rates have on the linear and nonlinear evolution of a typical plasma within a solar magnetic flux tube subject to the condensational instability. It is found that linear stability depends strongly on the heating rate. The results of numerical simulations of the nonlinear evolution of the condensational instability in a solar magnetic flux tube are presented. Different heating rates lead to quite different nonlinear evolutions, as evidenced by the behavior of the global internal energy.

Localization and characterization of an alpha-thrombin-binding site on platelet glycoprotein Ib alpha.

PubMed

De Marco, L; Mazzucato, M; Masotti, A; Ruggeri, Z M

1994-03-04

Glycoprotein (GP) Ib alpha is required for expression of the highest affinity alpha-thrombin-binding site on platelets, possibly contributing to platelet activation through a pathway involving cleavage of a specific receptor. This function may be important for the initiation of hemostasis and may also play a role in the development of pathological vascular occlusion. We have now identified a discrete sequence in the extracytoplasmic domain of GP Ib alpha, including residues 271-284 of the mature protein, which appears to be part of the high affinity alpha-thrombin-binding site. Synthetic peptidyl mimetics of this sequence inhibit alpha-thrombin binding to GP Ib as well as platelet activation and aggregation induced by subnanomolar concentrations of the agonist; they also inhibit alpha-thrombin binding to purified glycocalicin, the isolated extracytoplasmic portion of GP Ib alpha. The inhibitory peptides interfere with the clotting of fibrinogen by alpha-thrombin but not with the amidolytic activity of the enzyme on a small synthetic substrate, a finding compatible with the concept that the identified GP Ib alpha sequence interacts with the anion-binding exosite of alpha-thrombin but not with its active proteolytic site. The crucial structural elements of this sequence necessary for thrombin binding appear to be a cluster of negatively charged residues as well as three tyrosine residues that, in the native protein, may be sulfated. GP Ib alpha has no significant overall sequence homology with the thrombin inhibitor, hirudin, nor with the specific thrombin receptor on platelets; all three molecules, however, possess a distinct region rich in negatively charged residues that appear to be involved in thrombin binding. This may represent a case of convergent evolution of unrelated proteins for high affinity interaction with the same ligand.

A novel setup for wafer curvature measurement at very high heating rates.

PubMed

Islam, T; Zechner, J; Bernardoni, M; Nelhiebel, M; Pippan, R

2017-02-01

The curvature evolution of a thin film layer stack containing a top Al layer is measured during temperature cycles with very high heating rates. The temperature cycles are generated by means of programmable electrical power pulses applied to miniaturized polysilicon heater systems embedded inside a semiconductor chip and the curvature is measured by a fast wafer curvature measurement setup. Fast temperature cycles with heating duration of 100 ms are created to heat the specimen up to 270 °C providing an average heating rate of 2500 K/s. As a second approach, curvature measurement utilizing laser scanning Doppler vibrometry is also demonstrated which verifies the results obtained from the fast wafer curvature measurement setup. Film stresses calculated from the measured curvature values compare well to literature results, indicating that the new method can be used to measure curvature during fast temperature cycling.

An exploratory review on critical factors of IBS formwork implementation for Malaysian construction stakeholders

NASA Astrophysics Data System (ADS)

Baharuddin, Mohd Nurfaisal; Bahardin, Nur Fadhilah; Zaidi, Mohd Azian; Lokman, Ikhwan; Nawi, Mohd Nasrun Mohd

2016-08-01

The goals of this paper is to analysed the critical factors of driving or hindering the used of Industrialised Building System (IBS) formwork system in the Malaysian construction industry. Based on the reviews of a previous research and related literature, this paper was identified four (4) critical factor that classified as a difficulties to the success of IBS formwork system application; The issues related to the lack of knowledge and awareness, high cost and financial barriers, lack of incentive and promotion and lack of enforcement for government policy were highlight as a key dimension for the uses of IBS formwork system to success. The objective of this paper is to determine the importance factors in implementing IBS formwork in Malaysia. A preliminary survey which qualitative research approach has been adopted for this study as to validate the factors which found in the literature study. Based on the result analysis, it can be confirmed that the entire factors in literature review are strongly related with challenges in construction industry.

Probiotic Fermented Milk Containing Dietary Fiber Has Additive Effects in IBS with Constipation Compared to Plain Probiotic Fermented Milk.

PubMed

Choi, Sung Chul; Kim, Beom Jin; Rhee, Poong-Lyul; Chang, Dong Kyung; Son, Hee Jung; Kim, Jae J; Rhee, Jong Chul; Kim, Soon Im; Han, Young Sil; Sim, Ki Hyeon; Park, Seok Nam

2011-03-01

Although controversial, probiotics and dietary fiber are commonly used for patients with irritable bowel syndrome (IBS). We evaluated the effects of multistrain probiotics on the symptoms of IBS to determine whether the addition of dietary fi ber had an additive effect on constipation-predominant IBS. A total of 142 participants who met the Rome III criteria were recruited and randomized into a control group or a test group. Participants in the control group received multistrain probiotic fermented milk with Streptococcus thermophilus, Lactobacillus acidophilus and Bifidobacterium infantis; the participants in the test group received the same probiotic fermented milk mixed with dietary fi ber such as sea tangle extracts, radish extracts and glasswort extracts. The patients were treated for four weeks. Most of the symptoms of IBS, with the exception of fl atulence, stool consistency, and frequency of defecation, signifi cantly improved in both groups. In the analysis of IBS subtypes, especially constipation-predominant IBS, the frequency and duration of defecation and straining at stool were improved more in the test group than in the control group. Dietary fiber had additive benefits for the symptoms of constipation, especially in constipation-predominant IBS.

The Effect of Heat Treatments and Coatings on the Outgassing Rate of Stainless Steel Chambers

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

Mamum, Md Abdullah A.; Elmustafa, Abdelmageed A,; Stutzman, Marcy L.

The outgassing rates of four nominally identical 304L stainless steel vacuum chambers were measured to determine the effect of chamber coatings and heat treatments. One chamber was coated with titanium nitride (TiN) and one with amorphous silicon (a-Si) immediately following fabrication. One chamber remained uncoated throughout, and the last chamber was first tested without any coating, and then coated with a-Si following a series of heat treatments. The outgassing rate of each chamber was measured at room temperatures between 15 and 30 deg C following bakes at temperatures between 90 and 400 deg C. Measurements for bare steel showed amore » significant reduction in the outgassing rate by more than a factor of 20 after a 400 deg C heat treatment (3.5 x 10{sup 12} TorrL s{sup -1}cm{sup -2} prior to heat treatment, reduced to 1.7 x 10{ sup -13} TorrL s{sup -1}cm{sup -2} following heat treatment). The chambers that were coated with a-Si showed minimal change in outgassing rates with heat treatment, though an outgassing rate reduced by heat treatments prior to a-Si coating was successfully preserved throughout a series of bakes. The TiN coated chamber exhibited remarkably low outgassing rates, up to four orders of magnitude lower than the uncoated stainless steel. An evaluation of coating composition suggests the presence of elemental titanium which could provide pumping and lead to an artificially low outgassing rate. The outgassing results are discussed in terms of diffusion-limited versus recombination-limited processes.« less

Effect of surface roughness on the heating rates of large-angled hypersonic blunt cones

NASA Astrophysics Data System (ADS)

Irimpan, Kiran Joy; Menezes, Viren

2018-03-01

Surface-roughness caused by the residue of an ablative Thermal Protection System (TPS) can alter the turbulence level and surface heating rates on a hypersonic re-entry capsule. Large-scale surface-roughness that could represent an ablated TPS, was introduced over the forebody of a 120° apex angle blunt cone, in order to test for its influence on surface heating rates in a hypersonic freestream of Mach 8.8. The surface heat transfer rates measured on smooth and roughened models under the same freestream conditions were compared. The hypersonic flow-fields of the smooth and rough-surfaced models were visualized to analyse the flow physics. Qualitative numerical simulations and pressure measurements were carried out to have an insight into the high-speed flow physics. Experimental observations under moderate Reynolds numbers indicated a delayed transition and an overall reduction of 17-46% in surface heating rates on the roughened model.

Decreased TESK1-mediated cofilin 1 phosphorylation in the jejunum of IBS-D patients may explain increased female predisposition to epithelial dysfunction.

PubMed

Rodiño-Janeiro, Bruno K; Martínez, Cristina; Fortea, Marina; Lobo, Beatriz; Pigrau, Marc; Nieto, Adoración; González-Castro, Ana María; Salvo-Romero, Eloísa; Guagnozzi, Danila; Pardo-Camacho, Cristina; Iribarren, Cristina; Azpiroz, Fernando; Alonso-Cotoner, Carmen; Santos, Javier; Vicario, Maria

2018-02-02

Disturbed intestinal epithelial barrier and mucosal micro-inflammation characterize irritable bowel syndrome (IBS). Despite intensive research demonstrating ovarian hormones modulation of IBS severity, there is still limited knowledge on the mechanisms underlying female predominance in this disorder. Our aim was to identify molecular pathways involved in epithelial barrier dysfunction and female predominance in diarrhea-predominant IBS (IBS-D) patients. Total RNA and protein were obtained from jejunal mucosal biopsies from healthy controls and IBS-D patients meeting the Rome III criteria. IBS severity was recorded based on validated questionnaires. Gene and protein expression profiles were obtained and data integrated to explore biological and molecular functions. Results were validated by western blot. Tight junction signaling, mitochondrial dysfunction, regulation of actin-based motility by Rho, and cytoskeleton signaling were differentially expressed in IBS-D. Decreased TESK1-dependent cofilin 1 phosphorylation (pCFL1) was confirmed in IBS-D, which negatively correlated with bowel movements only in female participants. In conclusion, deregulation of cytoskeleton dynamics through TESK1/CFL1 pathway underlies epithelial intestinal dysfunction in the small bowel mucosa of IBS-D, particularly in female patients. Further understanding of the mechanisms involving sex-mediated regulation of mucosal epithelial integrity may have significant preventive, diagnostic, and therapeutic implications for IBS.

A Method for Determining the Rate of Heat Transfer from a Wing or Streamline Body

NASA Technical Reports Server (NTRS)

Frick, Charles W; Mccullough, George B

1945-01-01

A method for calculating the rate of heat transfer from the surface of an airfoil or streamline body is presented. A comparison with the results of an experimental investigation indicates that the accuracy of the method is good. This method may be used to calculate the heat supply necessary for heat de-icing or in ascertaining the heat loss from the fuselage of an aircraft operating at great altitude. To illustrate the method, the total rate of heat transfer from an airfoil is calculated and compared with the experimental results.

Abdominal bloating is the most bothersome symptom in irritable bowel syndrome with constipation (IBS-C): a large population-based Internet survey in Japan.

PubMed

Kanazawa, Motoyori; Miwa, Hiroto; Nakagawa, Ayako; Kosako, Masanori; Akiho, Hiraku; Fukudo, Shin

2016-01-01

Abdominal bloating is a common symptom in patients with irritable bowel syndrome with constipation (IBS-C). However, it is not included among the required items in the Rome III diagnostic criteria for IBS. Little is known about an impact of abdominal bloating seen in patients with IBS-C. Using a large population-based sample, the aim of the present study was to investigate what is the most bothersome symptom in subjects with IBS-C. An Internet survey of 30,000 adults drawn from the general public throughout Japan was conducted to identify subtypes of IBS using the Rome III diagnostic questionnaire. Consecutively, the screened subjects with IBS-C and the same number of age- and sex-matched non-IBS subjects who were randomly selected as controls were asked to answer a questionnaire on the degree of anxiety they experienced in their daily lives, thoughts about bowel habit, and their dominant gastrointestinal symptoms together with exacerbation factors (for IBS-C only). The screening survey showed that the prevalence of overall IBS was 16.5 % (female 17.4 %, male 15.5 %) and that 2.8 % met the criteria for IBS-C, 4.5 % for IBS with diarrhea (IBS-D) and 8.2 % for mixed IBS (IBS-M). Seven hundred and fifty-nine of 835 (90.9 %) subjects with IBS-C and 746 of 830 (89.9 %) control subjects completed the consecutive questionnaire. IBS-C subjects felt a higher degree of anxiety in their daily lives (p < 0.01) and considered bowel habit to be an indicator of health (p < 0.01) to a greater extent than control subjects. In IBS-C, the degree of anxiety was significantly associated with abdominal discomfort (p < 0.01), pain (p < 0.01) and bloating (p = 0.02), but not with the frequency of bowel habit (p > 0.1). Abdominal bloating was the most bothersome symptom (27.5 %), which was more likely to occur after a meal (52.2 %), at work/school (29.2 %) and during times of stress (26.8 %). Only 4.5 % of IBS-C subjects reported abdominal pain as the

Genetic recombination and Cryptosporidium hominis virulent subtype IbA10G2.

PubMed

Li, Na; Xiao, Lihua; Cama, Vitaliano A; Ortega, Ynes; Gilman, Robert H; Guo, Meijin; Feng, Yaoyu

2013-10-01

Little is known about the emergence and spread of virulent subtypes of Cryptosporidium hominis, the predominant species responsible for human cryptosporidiosis. We conducted sequence analyses of 32 genetic loci of 53 C. hominis specimens isolated from a longitudinally followed cohort of children living in a small community. We identified by linkage disequilibrium and recombination analyses only limited genetic recombination, which occurred exclusively within the 60-kDa glycoprotein gene subtype IbA10G2, a predominant subtype for outbreaks in industrialized nations and a virulent subtype in the study community. Intensive transmission of virulent subtype IbA10G2 in the study area might have resulted in genetic recombination with other subtypes. Moreover, we identified selection for IbA10G2 at a 129-kb region around the 60-kDa glycoprotein gene in chromosome 6. These findings improve our understanding of the origin and evolution of C. hominis subtypes and the spread of virulent subtypes.

Reduced Responses of Submucous Neurons from Irritable Bowel Syndrome Patients to a Cocktail Containing Histamine, Serotonin, TNFα, and Tryptase (IBS-Cocktail).

PubMed

Ostertag, Daniela; Buhner, Sabine; Michel, Klaus; Pehl, Christian; Kurjak, Manfred; Götzberger, Manuela; Schulte-Frohlinde, Ewert; Frieling, Thomas; Enck, Paul; Phillip, Josef; Schemann, Michael

2015-01-01

Malfunctions of enteric neurons are believed to play an important role in the pathophysiology of irritable bowel syndrome (IBS). Our aim was to investigate whether neuronal activity in biopsies from IBS patients is altered in comparison to healthy controls (HC). Activity of human submucous neurons in response to electrical nerve stimulation and local application of nicotine or a mixture of histamine, serotonin, tryptase, and TNF-α (IBS-cocktail) was recorded in biopsies from 17 HC and 35 IBS patients with the calcium-sensitive-dye Fluo-4 AM. The concentrations of the mediators resembeled those found in biopsy supernatants or blood. Neuronal activity in guinea-pig submucous neurons was studied with the voltage-sensitive-dye di-8-ANEPPS. Activity in submucous ganglia in response to nicotine or electrical nerve stimulation was not different between HC and IBS patients (P = 0.097 or P = 0.448). However, the neuronal response after application of the IBS-cocktail was significantly decreased (P = 0.039) independent of whether diarrhea (n = 12), constipation (n = 5) or bloating (n = 5) was the predominant symptom. In agreement with this we found that responses of submucous ganglia conditioned by overnight incubation with IBS mucosal biopsy supernatant to spritz application of this supernatant was significantly reduced (P = 0.019) when compared to incubation with HC supernatant. We demonstrated for the first time reduced neuronal responses in mucosal IBS biopsies to an IBS mediator cocktail. While excitability to classical stimuli of enteric neurons was comparable to HC, the activation by the IBS-cocktail was decreased. This was very likely due to desensitization to mediators constantly released by mucosal and immune cells in the gut wall of IBS patients.

Artificial Neural Networks-Based Software for Measuring Heat Collection Rate and Heat Loss Coefficient of Water-in-Glass Evacuated Tube Solar Water Heaters

PubMed Central

Liu, Zhijian; Liu, Kejun; Li, Hao; Zhang, Xinyu; Jin, Guangya; Cheng, Kewei

2015-01-01

Measurements of heat collection rate and heat loss coefficient are crucial for the evaluation of in service water-in-glass evacuated tube solar water heaters. However, conventional measurement requires expensive detection devices and undergoes a series of complicated procedures. To simplify the measurement and reduce the cost, software based on artificial neural networks for measuring heat collection rate and heat loss coefficient of water-in-glass evacuated tube solar water heaters was developed. Using multilayer feed-forward neural networks with back-propagation algorithm, we developed and tested our program on the basis of 915measuredsamples of water-in-glass evacuated tube solar water heaters. This artificial neural networks-based software program automatically obtained accurate heat collection rateand heat loss coefficient using simply "portable test instruments" acquired parameters, including tube length, number of tubes, tube center distance, heat water mass in tank, collector area, angle between tubes and ground and final temperature. Our results show that this software (on both personal computer and Android platforms) is efficient and convenient to predict the heat collection rate and heat loss coefficient due to it slow root mean square errors in prediction. The software now can be downloaded from http://t.cn/RLPKF08. PMID:26624613

Thermal sensation, rate of temperature change, and the heat dissipation design for tablet computers.

PubMed

Zhang, Han; Hedge, Alan; Cosley, Daniel

2017-07-01

Past research has shown that the rate of change of skin surface temperature can affect thermal sensation. This study investigated users' thermal responses to a tablet heating surface with different heat pads and different temperature change rates. The test conditions included: A. keeping the surface at a constant 42 °C, B. increasing the surface temperature from 38 °C to 42 °C at a rate of 0.02 °C/s in progressive intervals, C. increasing the temperature at 0.15 °C/s in progressive intervals, and D. Heating two left and right side pads alternately from 38 °C to 42 °C at 0.15 °C/s in progressive intervals. Overall results showed the lowest temperature change rate of 0.02 °C/s was most preferred in terms of thermal comfort. The findings suggest a potential to improve user thermal experience by dissipating tablet computer heat at a lower temperature change rate, or by alternating the dissipation areas. Copyright © 2017 Elsevier Ltd. All rights reserved.

Psychological comorbidity increases the risk for postinfectious IBS partly by enhanced susceptibility to develop infectious gastroenteritis.

PubMed

Wouters, Mira M; Van Wanrooy, Sander; Nguyen, Anh; Dooley, James; Aguilera-Lizarraga, Javier; Van Brabant, Winde; Garcia-Perez, Josselyn E; Van Oudenhove, Lukas; Van Ranst, Marc; Verhaegen, Jan; Liston, Adrian; Boeckxstaens, Guy

2016-08-01

Psychological factors increase the risk to develop postinfectious IBS (PI-IBS), but the mechanisms involved are unclear. As stress affects the immune system, we investigated the potential interaction between psychological factors, the immune response against infectious gastroenteritis (IGE) and the development of IGE and PI-IBS in a large cohort exposed to contaminated drinking water. 18 620 people exposed to contaminated drinking water (norovirus, Giardia lamblia, Campylobacter jejuni) were invited to participate in a prospective controlled cohort study. They were asked to complete questionnaires assessing demographic, psychological and clinical data during the outbreak and 1 year later. At both time points, in-depth immune function (peripheral blood and rectal biopsies) was studied in a subgroup of subjects. 1379 subjects completed the questionnaires during the outbreak, of which 271 developed IGE. Risk factors for IGE included younger age, pre-existing dyspepsia-like symptoms, anxiety and drinking contaminated tap water. Anxiety scores before the outbreak inversely correlated with interleukin-2-expressing CD4+ T cells (r=0.6, p=0.01, n=23). At follow-up, 34 of 172 (20%) IGE subjects developed IBS compared with 24/366 exposed participants (7%, p<0.0001, χ(2) test). A Th2 cytokine phenotype at time of infection was associated with increased risk for PI-IBS 1 year later. Except for increased B cell numbers, no evidence for systemic or rectal mucosal immune activation in PI-IBS was demonstrated at follow-up. Our study shows that the increased risk of patients with psychological comorbidity to develop PI-IBS may partly result from an increased susceptibility to develop IGE, possibly resulting from a Th2-immune bias. (ClinicalTrials.gov NCT01497847). Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Calorimeter measures high nuclear heating rates and their gradients across a reactor test hole

NASA Technical Reports Server (NTRS)

Burwell, D.; Coombe, J. R.; Mc Bride, J.

1970-01-01

Pedestal-type calorimeter measures gamma-ray heating rates from 0.5 to 7.0 watts per gram of aluminum. Nuclear heating rate is a function of cylinder temperature change, measured by four chromel-alumel thermocouples attached to the calorimeter, and known thermoconductivity of the tested material.

TRPA1 Is Functionally Expressed Primarily by IB4-Binding, Non-Peptidergic Mouse and Rat Sensory Neurons

PubMed Central

Stucky, Cheryl L.

2012-01-01

Subpopulations of somatosensory neurons are characterized by functional properties and expression of receptor proteins and surface markers. CGRP expression and IB4-binding are commonly used to define peptidergic and non-peptidergic subpopulations. TRPA1 is a polymodal, plasma membrane ion channel that contributes to mechanical and cold hypersensitivity during tissue injury, making it a key target for pain therapeutics. Some studies have shown that TRPA1 is predominantly expressed by peptidergic sensory neurons, but others indicate that TRPA1 is expressed extensively within non-peptidergic, IB4-binding neurons. We used FURA-2 calcium imaging to define the functional distribution of TRPA1 among peptidergic and non-peptidergic adult mouse (C57BL/6J) DRG neurons. Approximately 80% of all small-diameter (<27 µm) neurons from lumbar 1–6 DRGs that responded to TRPA1 agonists allyl isothiocyanate (AITC; 79%) or cinnamaldehyde (84%) were IB4-positive. Retrograde labeling via plantar hind paw injection of WGA-Alexafluor594 showed similarly that most (81%) cutaneous neurons responding to TRPA1 agonists were IB4-positive. Additionally, we cultured DRG neurons from a novel CGRP-GFP mouse where GFP expression is driven by the CGRPα promoter, enabling identification of CGRP-expressing live neurons. Interestingly, 78% of TRPA1-responsive neurons were CGRP-negative. Co-labeling with IB4 revealed that the majority (66%) of TRPA1 agonist responders were IB4-positive but CGRP-negative. Among TRPA1-null DRGs, few small neurons (2–4%) responded to either TRPA1 agonist, indicating that both cinnamaldehyde and AITC specifically target TRPA1. Additionally, few large neurons (≥27 µm diameter) responded to AITC (6%) or cinnamaldehyde (4%), confirming that most large-diameter somata lack functional TRPA1. Comparison of mouse and rat DRGs showed that the majority of TRPA1-responsive neurons in both species were IB4-positive. Together, these data demonstrate that TRPA1 is functionally

Learning Negotiation Policies Using IB3 and Bayesian Networks

NASA Astrophysics Data System (ADS)

Nalepa, Gislaine M.; Ávila, Bráulio C.; Enembreck, Fabrício; Scalabrin, Edson E.

This paper presents an intelligent offer policy in a negotiation environment, in which each agent involved learns the preferences of its opponent in order to improve its own performance. Each agent must also be able to detect drifts in the opponent's preferences so as to quickly adjust itself to their new offer policy. For this purpose, two simple learning techniques were first evaluated: (i) based on instances (IB3) and (ii) based on Bayesian Networks. Additionally, as its known that in theory group learning produces better results than individual/single learning, the efficiency of IB3 and Bayesian classifier groups were also analyzed. Finally, each decision model was evaluated in moments of concept drift, being the drift gradual, moderate or abrupt. Results showed that both groups of classifiers were able to effectively detect drifts in the opponent's preferences.

Enhancement of heat transfer rate on phase change materials with thermocapillary flows

NASA Astrophysics Data System (ADS)

Madruga, Santiago; Mendoza, Carolina

2017-04-01

We carry out simulations of the melting process on the phase change material n-octadecane in squared geometries in the presence of natural convection and including thermocapillary effects. We show how the introduction of thermocapillary effects enhances the heat transfer rate, being the effect especially relevant for small Bond numbers. Thus induction of Marangoni flows results in a useful mechanism to enhance the typical slow heat transfer rate of paraffin waxes in applications of energy storage or passive control management.

A Simple Rate Law Experiment Using a Custom-Built Isothermal Heat Conduction Calorimeter

ERIC Educational Resources Information Center

Wadso, Lars; Li, Xi.

2008-01-01

Most processes (whether physical, chemical, or biological) produce or consume heat: measuring thermal power (the heat production rate) is therefore a typical method of studying processes. Here we describe the design of a simple isothermal heat conduction calorimeter built for use in teaching; we also provide an example of its use in simultaneously…

Neuroimmune interactions at different intestinal sites are related to abdominal pain symptoms in children with IBS

USDA-ARS?s Scientific Manuscript database

Neuroimmune interactions and inflammation have been proposed as factors involved in sensory-motor dysfunction and symptom generation in adult irritable bowel syndrome (IBS) patients. In children with IBS and healthy controls, we measured ileocolonic mast cell infiltration and fecal calprotectin and ...

Effect of acupuncture and its influence on visceral hypersensitivity in IBS-D patients: Study protocol for a randomized controlled trial.

PubMed

Pei, Lixia; Chen, Hao; Guo, Jing; Chen, Lu; Wu, Xiaoliang; Xu, Wanli; Weng, Shengjie; Yang, EunMee; Hammer, Trine; Sun, Jianhua

2018-05-01

Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder associated with visceral hypersensitivity. Increased expression of colonic TRPV1 and decreased expression of microRNA-199 are implicated in the pathogenesis of visceral hypersensitivity in IBS-D patients. Acupuncture is one of the frequently used complementary and alternative therapies for the treatment of IBS. The existing clinical studies mostly use IBS-SSS or other subjective scales, so there is a lack of objective biochemical evidence regarding the effect of acupuncture on IBS. Therefore, we designed this study to investigate whether acupuncture alleviate visceral hypersensitivity by influencing the expression of TRPV1 and microRNA-199. This study is a randomized, sham-controlled trial involving 40 patients and 10 healthy volunteers. A total of 40 eligible patients with IBS-D will be randomly assigned to a traditional acupuncture group or sham acupuncture group in a 1:1 ratio. Patients will receive 3 acupuncture treatment sessions per week for 12 consecutive weeks, for a total of 36 sessions during the study. The primary outcome measure is the IBS-Symptom Severity Score (IBS-SSS). Secondary outcomes are Visceral Pain Scale and levels of TRPV1 and microRNA-199 in colonic tissues. Healthy volunteers will not receive any clinical intervention. The safety of interventions will be assessed at every visit. The purpose of this trial is to evaluate the efficacy of acupuncture for IBS-D through IBS-SSS and Visceral Pain Scale. Furthermore, we want to explore the intervention mechanism of acupuncture in improving visceral hypersensitivity by analyzing the colonic TRPV1 and microRNA-199. This trial is registered with Chinese Clinical Trials Register, ChiCTR-IOR- 17010860(http://www.chictr.org.cn/showproj.aspx?proj=18445).

Multivariate modelling of faecal bacterial profiles of patients with IBS predicts responsiveness to a diet low in FODMAPs.

PubMed

Bennet, Sean M P; Böhn, Lena; Störsrud, Stine; Liljebo, Therese; Collin, Lena; Lindfors, Perjohan; Törnblom, Hans; Öhman, Lena; Simrén, Magnus

2018-05-01

The effects of dietary interventions on gut bacteria are ambiguous. Following a previous intervention study, we aimed to determine how differing diets impact gut bacteria and if bacterial profiles predict intervention response. Sixty-seven patients with IBS were randomised to traditional IBS (n=34) or low fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs) (n=33) diets for 4 weeks. Food intake was recorded for 4 days during screening and intervention. Faecal samples and IBS Symptom Severity Score (IBS-SSS) reports were collected before (baseline) and after intervention. A faecal microbiota dysbiosis test (GA-map Dysbiosis Test) evaluated bacterial composition. Per protocol analysis was performed on 61 patients from whom microbiome data were available. Responders (reduced IBS-SSS by ≥50) to low FODMAP, but not traditional, dietary intervention were discriminated from non-responders before and after intervention based on faecal bacterial profiles. Bacterial abundance tended to be higher in non-responders to a low FODMAP diet compared with responders before and after intervention. A low FODMAP intervention was associated with an increase in Dysbiosis Index (DI) scores in 42% of patients; while decreased DI scores were recorded in 33% of patients following a traditional IBS diet. Non-responders to a low FODMAP diet, but not a traditional IBS diet had higher DI scores than responders at baseline. Finally, while a traditional IBS diet was not associated with significant reduction of investigated bacteria, a low FODMAP diet was associated with reduced Bifidobacterium and Actinobacteria in patients, correlating with lactose consumption. A low FODMAP, but not a traditional IBS diet may have significant impact on faecal bacteria. Responsiveness to a low FODMAP diet intervention may be predicted by faecal bacterial profiles. NCT02107625. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a

Reduced Responses of Submucous Neurons from Irritable Bowel Syndrome Patients to a Cocktail Containing Histamine, Serotonin, TNFα, and Tryptase (IBS-Cocktail)

PubMed Central

Ostertag, Daniela; Buhner, Sabine; Michel, Klaus; Pehl, Christian; Kurjak, Manfred; Götzberger, Manuela; Schulte-Frohlinde, Ewert; Frieling, Thomas; Enck, Paul; Phillip, Josef; Schemann, Michael

2015-01-01

Background and Aims: Malfunctions of enteric neurons are believed to play an important role in the pathophysiology of irritable bowel syndrome (IBS). Our aim was to investigate whether neuronal activity in biopsies from IBS patients is altered in comparison to healthy controls (HC). Methods: Activity of human submucous neurons in response to electrical nerve stimulation and local application of nicotine or a mixture of histamine, serotonin, tryptase, and TNF-α (IBS-cocktail) was recorded in biopsies from 17 HC and 35 IBS patients with the calcium-sensitive-dye Fluo-4 AM. The concentrations of the mediators resembeled those found in biopsy supernatants or blood. Neuronal activity in guinea-pig submucous neurons was studied with the voltage-sensitive-dye di-8-ANEPPS. Results: Activity in submucous ganglia in response to nicotine or electrical nerve stimulation was not different between HC and IBS patients (P = 0.097 or P = 0.448). However, the neuronal response after application of the IBS-cocktail was significantly decreased (P = 0.039) independent of whether diarrhea (n = 12), constipation (n = 5) or bloating (n = 5) was the predominant symptom. In agreement with this we found that responses of submucous ganglia conditioned by overnight incubation with IBS mucosal biopsy supernatant to spritz application of this supernatant was significantly reduced (P = 0.019) when compared to incubation with HC supernatant. Conclusion: We demonstrated for the first time reduced neuronal responses in mucosal IBS biopsies to an IBS mediator cocktail. While excitability to classical stimuli of enteric neurons was comparable to HC, the activation by the IBS-cocktail was decreased. This was very likely due to desensitization to mediators constantly released by mucosal and immune cells in the gut wall of IBS patients. PMID:26733780

Isothermal calorimeter for measurements of time-dependent heat generation rate in individual supercapacitor electrodes

NASA Astrophysics Data System (ADS)

Munteshari, Obaidallah; Lau, Jonathan; Krishnan, Atindra; Dunn, Bruce; Pilon, Laurent

2018-01-01

Heat generation in electric double layer capacitors (EDLCs) may lead to temperature rise and reduce their lifetime and performance. This study aims to measure the time-dependent heat generation rate in individual carbon electrode of EDLCs under various charging conditions. First, the design, fabrication, and validation of an isothermal calorimeter are presented. The calorimeter consisted of two thermoelectric heat flux sensors connected to a data acquisition system, two identical and cold plates fed with a circulating coolant, and an electrochemical test section connected to a potentiostat/galvanostat system. The EDLC cells consisted of two identical activated carbon electrodes and a separator immersed in an electrolyte. Measurements were performed on three cells with different electrolytes under galvanostatic cycling for different current density and polarity. The measured time-averaged irreversible heat generation rate was in excellent agreement with predictions for Joule heating. The reversible heat generation rate in the positive electrode was exothermic during charging and endothermic during discharging. By contrast, the negative electrode featured both exothermic and endothermic heat generation during both charging and discharging. The results of this study can be used to validate existing thermal models, to develop thermal management strategies, and to gain insight into physicochemical phenomena taking place during operation.

Molecular dynamics simulations of aggregation of copper nanoparticles with different heating rates

NASA Astrophysics Data System (ADS)

Li, Qibin; Wang, Meng; Liang, Yunpei; Lin, Liyang; Fu, Tao; Wei, Peitang; Peng, Tiefeng

2017-06-01

Molecular dynamics simulations were employed to investigate the heating rates' effect on aggregation of two copper nanoparticles. The aggregation can be distinguished into three distinct regimes by the contacting and melting of nanoparticles. The nanoparticles contacting at a lower temperature during the sintering with lower heating rate, meanwhile, some temporary stacking fault exists at the contacting neck. The aggregation properties of the system, i.e. neck diameter, shrinkage ratio, potential energy, mean square displacement (MSD) and relative gyration radius, experience drastic changes due to the free surface annihilation. After the nanoparticles coalesced for a stable period, the shrinkage ratio, MSD, relative gyration radius and neck diameter of the system are dramatically changed during the melting process. It is shown that the shrinkage ratio and MSD have relative larger increasing ratio for a lower heating rate. While the evolution of the relative gyration radius and neck diameter is only sensitive to the temperature.

Heat transfer rate and film cooling effectiveness measurements in a transient cascade

NASA Astrophysics Data System (ADS)

Schultz, D. L.; Oldfield, M. L. G.; Jones, T. V.

1980-09-01

A transient cascade useful for heat transfer rate measurements is briefly described. The facility employs a free piston which compresses the test gas to temperatures around 450 K and pressures of about 3.5 to 7.5 Atm. The model is initially at room temperature and it is necessary to attain the correct gas to wall temperature ratio. The exit Mach number is set by the inlet total pressure and the pressure in the exit dump tank. Thin film heat transfer gauges are used for the measurement of heat transfer rate, deposited on machineable glass ceramic blades. The inherently fast response of these transducers makes them useful for the investigation of boundary layer transition on blade surfaces and some typical results are included.

A new method using insert-based systems (IBS) to improve cell behavior study on flexible and rigid biomaterials.

PubMed

Grenade, Charlotte; Moniotte, Nicolas; Rompen, Eric; Vanheusden, Alain; Mainjot, Amélie; De Pauw-Gillet, Marie-Claire

2016-12-01

In vitro studies about biomaterials biological properties are essential screening tests. Yet cell cultures encounter difficulties related to cell retention on material surface or to the observation of both faces of permeable materials. The objective of the present study was to develop a reliable in vitro method to study cell behavior on rigid and flexible/permeable biomaterials elaborating two specific insert-based systems (IBS-R and IBS-F respectively). IBS-R was designed as a specific cylindrical polytetrafluoroethylene (PTFE) system to evaluate attachment, proliferation and morphology of human gingival fibroblasts (HGFs) on grade V titanium and lithium disilicate glass-ceramic discs characteristics of dental prostheses. The number of cells, their covering on discs and their morphology were determined from MTS assays and microscopic fluorescent images after 24, 48 and 72 h. IBS-F was developed as a two components system to study HGFs behavior on guided bone regeneration polyester membranes. The viability and the membrane barrier effect were evaluated by metabolic MTS assays and by scanning electron microscopy. IBS-R and IBS-F were shown to promote (1) easy and rapid handling; (2) cell retention on biomaterial surface; (3) accurate evaluation of the cellular proliferation, spreading and viability; (4) use of non-toxic material. Moreover IBS-F allowed the study of the cell migration through degradable membranes, with an access to both faces of the biomaterial and to the bottom of culture wells for medium changing.

Effects of supplemental chromium picolinate and chromium nanoparticles on performance and antibody titers of infectious bronchitis and avian influenza of broiler chickens under heat stress condition.

PubMed

Hajializadeh, Farhad; Ghahri, Hasan; Talebi, Alireza

2017-01-01

This experiment was carried out to investigate the effects of different levels chromium picolinate (CrPic) and chromium nanoparticles (nano-Cr) on the performance and immune function of broilers under heat stress condition. A total of 320 Ross 308 broiler chicks (from 21 to 42 days) were assigned randomly into eight treatment groups (four replicates per treatment, and 10 chicks per replicate) and be reared at either thermoneutral (21 ˚C) or heat stress (36 ◦ C). The treatments were control (T1) group without supplementation and heat stress, T2 as a heat stress group without supplementation, T3, T4 and T5 groups which were supplemented with 500, 1000 and 1500 ppb CrPic in diet with heat stress, respectively and T6, T7 and T8 groups which were supplemented with 500, 1000 and 1500 ppb nano-chromium in diet under heat stress, respectively. Supplementation of chromium and nano-chromium improved performance including weight gain and feed conversion ratio of heat-stressed chickens. Antibody titers against avian influenza (AI) and infectious bronchitis (IB) at 21 to 42 days of age in broilers fed supplemental chromium and nano-chromium were higher than broiler chickens fed control diet ( p < 0.05). Nano-chromium supplementation at level of 1000 ppb and CrPic at level of 1500 ppb improved the antibody titers against AI and IB of broilers under heat stress conditions. It can be concluded from these findings that dietary supplementation of CrPic and nano-Cr can improve performance and antibody titers against AI and IB under heat stress conditions in broilers.

Baroreceptor unloading does not limit forearm sweat rate during severe passive heat stress.

PubMed

Schlader, Zachary J; Gagnon, Daniel; Lucas, Rebekah A I; Pearson, James; Crandall, Craig G

2015-02-15

This study tested the hypothesis that sweat rate during passive heat stress is limited by baroreceptor unloading associated with heat stress. Two protocols were performed in which healthy subjects underwent passive heat stress that elicited an increase in intestinal temperature of ∼1.8°C. Upon attaining this level of hyperthermia, in protocol 1 (n = 10, 3 females) a bolus (19 ml/kg) of warm (∼38°C) isotonic saline was rapidly (5-10 min) infused intravenously to elevate central venous pressure (CVP), while in protocol 2 (n = 11, 5 females) phenylephrine was infused intravenously (60-120 μg/min) to return mean arterial pressure (MAP) to normothermic levels. In protocol 1, heat stress reduced CVP from 3.9 ± 1.9 mmHg (normothermia) to -0.6 ± 1.4 mmHg (P < 0.001), while saline infusion returned CVP to normothermic levels (5.1 ± 1.7 mmHg; P > 0.999). Sweat rate was elevated by heat stress (1.21 ± 0.44 mg·cm(-2)·min(-1)) but remained unchanged during rapid saline infusion (1.26 ± 0.47 mg·cm(-2)·min(-1), P = 0.5), whereas cutaneous vascular conductance increased from 77 ± 10 to 101 ± 20% of local heating max (P = 0.029). In protocol 2, MAP was reduced with heat stress from 85 ± 7 mmHg to 76 ± 8 mmHg (P = 0.048). Although phenylephrine infusion returned MAP to normothermic levels (88 ± 7 mmHg; P > 0.999), sweat rate remained unchanged during phenylephrine infusion (1.39 ± 0.22 vs. 1.41 ± 0.24 mg·cm(-2)·min(-1); P > 0.999). These data indicate that both cardiopulmonary and arterial baroreceptor unloading do not limit increases in sweat rate during passive heat stress. Copyright © 2015 the American Physiological Society.

Hysteresis of heart rate and heat exchange of fasting and postprandial savannah monitor lizards (Varanus exanthematicus).

PubMed

Zaar, Morten; Larsen, Einer; Wang, Tobias

2004-04-01

Reptiles are ectothermic, but regulate body temperatures (T(b)) by behavioural and physiological means. Body temperature has profound effects on virtually all physiological functions. It is well known that heating occurs faster than cooling, which seems to correlate with changes in cutaneous perfusion. Increased cutaneous perfusion, and hence elevated cardiac output, during heating is reflected in an increased heart rate (f(H)), and f(H), at a given T(b), is normally higher during heating compared to cooling ('hysteresis of heart rate'). Digestion is associated with an increased metabolic rate. This is associated with an elevated f(H) and many species of reptiles also exhibited a behavioural selection of higher T(b) during digestion. Here, we examine whether digestion affects the rate of heating and cooling as well as the hysteresis of heart rate in savannah monitor lizards (Varanus exanthematicus). Fasting lizards were studied after 5 days of food deprivation while digesting lizards were studied approximately 24 h after ingesting dead mice that equalled 10% of their body mass. Heart rate was measured while T(b) increased from 28 to 38 degrees C under a heat lamp and while T(b) decreased during a subsequent cooling phase. The lizards exhibited hysteresis of heart rate, and heating occurred faster than cooling. Feeding led to an increased f(H) (approximately 20 min(-1) irrespective of T(b)), but did not affect the rate of temperature change during heating or cooling. Therefore, it is likely that the increased blood flows during digestion are distributed exclusively to visceral organs and that the thermal conductance remains unaffected by the elevated metabolic rate during digestion.

Effects of gut-directed hypnotherapy on IBS in different clinical settings-results from two randomized, controlled trials.

PubMed

Lindfors, Perjohan; Unge, Peter; Arvidsson, Patrik; Nyhlin, Henry; Björnsson, Einar; Abrahamsson, Hasse; Simrén, Magnus

2012-02-01

Gut-directed hypnotherapy has been found to be effective in irritable bowel syndrome (IBS). However, randomized, controlled studies are rare and few have been performed outside highly specialized research centers. The objective of this study was to study the effect of gut-directed hypnotherapy in IBS in different clinical settings outside the traditional research units. The study population included IBS patients refractory to standard management. In study 1, patients were randomized to receive gut-directed hypnotherapy (12 sessions, 1 h/week) in psychology private practices or supportive therapy, whereas patients were randomized to receive gut-directed hypnotherapy in a small county hospital or to serve as waiting list controls in study 2. Gastrointestinal symptom severity and quality of life were evaluated at baseline, at 3 months follow-up and after 1 year. We randomized 138 IBS patients refractory to standard management, 90 in study 1 and 48 in study 2. In both the studies, IBS-related symptoms were improved at 3 months in the gut-directed hypnotherapy groups (P<0.05), but not in the control groups (ns). In study 1, a significantly greater improvement of IBS-related symptom severity could be detected in the gut-directed hypnotherapy group than in the control group (P<0.05), and a trend in the same direction was seen in study 2 (P=0.17). The results seen at 3 months were sustained up to 1 year. Gut-directed hypnotherapy is an effective treatment alternative for patients with refractory IBS, but the effectiveness is lower when the therapy is given outside the highly specialized research centers.

Apples and Oranges: Comparing the Backgrounds and Academic Trajectories of International Baccalaureate (IB) Students to a Matched Comparison Group

ERIC Educational Resources Information Center

May, Henry; Rodriguez, Awilda; Sirinides, Philip M.; Perna, Laura W.; Yee, April; Ransom, Tafaya

2013-01-01

As a critical step in understanding the impacts of IB, the analyses presented in this report examined the selection mechanisms behind IB participation across Florida, the state with the second highest representation of IB programs in the nation. We use longitudinal student and school-level data from 1995 through 2009 from the Florida K-20…

Gastrointestinal (GI) permeability is associated with trait anxiety in children with functional abdominal pain (FAP) and Irritable Bowel Syndrome (IBS)

USDA-ARS?s Scientific Manuscript database

FAP and IBS affect 10-15% of school age children and bear many physiological similarities to irritable bowel syndrome (IBS) in adults (e.g., functional pain, visceral hyperalgesia). Animal models of IBS have suggested a relationship between neonatal stress and increased GI permeability later in life...

Reduced interstitial cells of Cajal and increased intraepithelial lymphocytes are associated with development of small intestinal bacterial overgrowth in post-infectious IBS mouse model.

PubMed

Chen, Binrui; Zhu, Shuwen; Du, Lijun; He, Huiqin; Kim, John J; Dai, Ning

2017-10-01

Intestinal dysmotility and immune activation are likely involved in the pathogenesis of small intestinal bacteria overgrowth (SIBO) in irritable bowel syndrome (IBS). We aimed at investigating the role of interstitial cells of Cajal (ICC) and intestinal inflammation in the development of SIBO using a post-infectious IBS (PI-IBS) mouse model. NIH mice were randomly infected with Trichinella spiralis. Visceral sensitivity and stool pattern were assessed at 8-weeks post-infection (PI). Intestinal bacteria counts from jejunum and ileum were measured by quantitative real-time PCR to evaluate the presence of SIBO. ICC density, intraepithelial lymphocytes (IELs) counts, and intestinal cytokine levels (IL1-β, IL-6, toll-like receptor-4 (TLR-4), IL-10) in the ileum were examined. PI-IBS mice demonstrated increased visceral sensitivity compared with the control group. One-third of the PI-IBS mice developed SIBO (SIBO+/PI-IBS) and was more likely to have abnormal stool form compared with SIBO negative PI-IBS (SIBO-/PI-IBS) mice but without difference in visceral sensitivity. SIBO+/PI-IBS mice had decreased ICC density and increased IELs counts in the ileum compared with SIBO-/PI-IBS mice. No difference in inflammatory cytokine expression levels were detected among the groups except for increased TLR-4 in PI-IBS mice compared with the control group. Development of SIBO in PI-IBS mice was associated with reduced ICC density and increased IELs counts in the ileum. Our findings support the role of intestinal dysmotility and inflammation in the pathogenesis of SIBO in IBS and may provide potential therapeutic targets.

Clopidogrel IBS Patients Have Higher Incidence of Gastrointestinal Symptoms Influenced by Age and Gender.

PubMed

Soghomonyan, Suren; Abdel-Rasoul, Mahmoud; Zuleta-Alarcon, Alix; Grants, Iveta; Davila, Victor; Yu, Jeffrey; Zhang, Cheng; Whitaker, Emmett E; Bergese, Sergio D; Stoicea, Nicoleta; Arsenescu, Razvan; Christofi, Fievos L

2017-10-01

Clopidogrel is an irreversible antagonist of P2Y 12 receptors (P2Y 12 Rs) used as an antiplatelet drug to reduce risk of thrombosis. P2Y 12 Rs are expressed in gastrointestinal (GI) tract where they might regulate GI function. To evaluate if blockade of P2Y 12 Rs by clopidogrel is associated with higher incidence of GI symptoms in patients with irritable bowel syndrome (IBS). A retrospective analysis of our institutional database was conducted for a 13-year period. IBS patients were identified, and their demographics, GI symptoms and clopidogrel therapy were collected. Logistic regression models were used to characterize symptoms in clopidogrel versus no-clopidogrel IBS-groups, adjusting for Age and Sex differences. An additional study characterized the P2Y 12 R distribution in human gut. The search identified 7217 IBS patients (6761 no-clopidogrel/456 clopidogrel). There were a higher proportion of patients with GI symptoms on clopidogrel (68%) compared to controls (60%, p = 0.0011) that were Females (70 vs. 60%, p = 0.0003) not Males (61 vs. 60%; p = 0.8312). In Females, clopidogrel was associated with higher incidence of GI symptoms (Age adjusted; p < 0.0001) for pain, constipation, gastroparesis (p ≤ 0.0001) and psychogenic pain (p = 0.0006). Age or Sex (adjusted models) influenced one or more GI symptoms (i.e., pain, p < 0.0001; constipation, p < 0.0001/p = 0.008; diarrhea, flatulence, p = 0.01). P2Y 12 R immunoreactivity was abundant in human ENS; glial-to-neuron ratio of P2Y 12 Rs expressed in Females ≫ Males. Irreversible blockade of P2Y 12 R by clopidogrel is associated with higher incidence of GI symptoms in Female IBS patients, although Age or Sex alone contributes to symptomatology. Prospective studies can determine clinical implications of P2Y 12 Rs in IBS.

Heat and water rate transfer processes in the human respiratory tract at various altitudes.

PubMed

Kandjov, I M

2001-02-01

The process of the respiratory air conditioning as a process of heat and mass exchange at the interface inspired air-airways surface was studied. Using a model of airways (Olson et al., 1970) where the segments of the respiratory tract are like cylinders with a fixed length and diameter, the corresponding heat transfer equations, in the paper are founded basic rate exchange parameters-convective heat transfer coefficient h(c)(W m(-2) degrees C(-1)) and evaporative heat transfer coefficient h(e)(W m(-2)hPa(-1)). The rate transfer parameters assumed as sources with known heat power are connected to airflow rate in different airways segments. Relationships expressing warming rate of inspired air due to convection, warming rate of inspired air due to evaporation, water diffused in the inspired air from the airways wall, i.e. a system of air conditioning parameters, was composed. The altitude dynamics of the relations is studied. Every rate conditioning parameter is an increasing function of altitude. The process of diffusion in the peripheral bronchial generations as a basic transfer process is analysed. The following phenomenon is in effect: the diffusion coefficient increases with altitude and causes a compensation of simultaneous decreasing of O(2)and CO(2)densities in atmospheric air. Due to this compensation, the diffusion in the peripheral generations with altitude is approximately constant. The elements of the human anatomy optimality as well as the established dynamics are discussed and assumed. The square form of the airways after the trachea expressed in terms of transfer supposes (in view of maximum contact surface), that a maximum heat and water exchange is achieved, i.e. high degree of air condition at fixed environmental parameters and respiration regime. Copyright 2001 Academic Press.

BmprIa is required in mesenchymal tissue and has limited redundant function with BmprIb in tooth and palate development

PubMed Central

Li, Lu; Lin, Minkui; Wang, Ying; Cserjesi, Peter; Chen, Zhi; Chen, YiPing

2010-01-01

The BMP signaling plays a pivotal role in the development of craniofacial organs, including the tooth and palate. BmprIa and BmprIb encode two type I BMP receptors that are primarily responsible for BMP signaling transduction. We investigated mesenchymal tissue-specific requirement of BmprIa and its functional redundancy with BmprIb during the development of mouse tooth and palate. BmprIa and BmprIb exhibit partially overlapping and distinct expression patterns in the developing tooth and palatal shelf. Neural crest specific inactivation of BmprIa leads to formation of an unusual type of anterior clefting of the secondary palate, an arrest of tooth development at the bud/early cap stages, and severe hypoplasia of the mandible. Defective tooth and palate development is accompanied by the down-regulation of BMP responsive genes and reduced cell proliferation levels in the palatal and dental mesenchyme. To determine if BmprIb could substitute for BmprIa during tooth and palate development, we expressed a constitutively active form of BmprIb (caBmprIb) in the neural crest cells in which BmprIa was simultaneously inactivated. We found that substitution of BmprIa by caBmprIb in neural rest cells rescues the development of molars and maxillary incisor, but the rescued teeth exhibit a delayed odontoblast and ameloblast differentiation. In contrast, caBmprIb fails to rescue the palatal and mandibular defects including the lack of lower incisors. Our results demonstrate an essential role for BmprIa in the mesenchymal component and a limited functional redundancy between BmprIa and BmprIb in a tissue specific manner during tooth and palate development. PMID:21034733

Particle loading rates for HVAC filters, heat exchangers, and ducts.

PubMed

Waring, M S; Siegel, J A

2008-06-01

The rate at which airborne particulate matter deposits onto heating, ventilation, and air-conditioning (HVAC) components is important from both indoor air quality (IAQ) and energy perspectives. This modeling study predicts size-resolved particle mass loading rates for residential and commercial filters, heat exchangers (i.e. coils), and supply and return ducts. A parametric analysis evaluated the impact of different outdoor particle distributions, indoor emission sources, HVAC airflows, filtration efficiencies, coils, and duct system complexities. The median predicted residential and commercial loading rates were 2.97 and 130 g/m(2) month for the filter loading rates, 0.756 and 4.35 g/m(2) month for the coil loading rates, 0.0051 and 1.00 g/month for the supply duct loading rates, and 0.262 g/month for the commercial return duct loading rates. Loading rates are more dependent on outdoor particle distributions, indoor sources, HVAC operation strategy, and filtration than other considered parameters. The results presented herein, once validated, can be used to estimate filter changing and coil cleaning schedules, energy implications of filter and coil loading, and IAQ impacts associated with deposited particles. The results in this paper suggest important factors that lead to particle deposition on HVAC components in residential and commercial buildings. This knowledge informs the development and comparison of control strategies to limit particle deposition. The predicted mass loading rates allow for the assessment of pressure drop and indoor air quality consequences that result from particle mass loading onto HVAC system components.

Molecular detection and genetic analysis of Akabane virus genogroup Ib in small ruminants in Turkey.

PubMed

Şevik, Murat

2017-09-01

Akabane disease is a viral disease transmitted by biting midges and can cause teratogenic malformations in cattle, sheep and goats. Abortion outbreaks associated with arthrogryposis and cerebellar hypoplasia in two epidemiologically independent flocks were reported in the Mediterranean region of Turkey in 2015. Phylogenetic analysis based on nucleocapsid (N) gene sequences showed that the field isolates presented here belong to the genogroup Ib. The akabane virus (AKAV) field isolates analysed in this study displayed 6 new amino acid substitutions in N and non-structural protein chains compared with those of AKAV strains belonging to genogroup Ib. To the best of our knowledge, this is the first report on the presence of the AKAV genogroup Ib in Turkey.

BDNF contributes to IBS-like colonic hypersensitivity via activating the enteroglia-nerve unit

PubMed Central

Wang, Peng; Du, Chao; Chen, Fei-Xue; Li, Chang-Qing; Yu, Yan-Bo; Han, Ting; Akhtar, Suhail; Zuo, Xiu-Li; Tan, Xiao-Di; Li, Yan-Qing

2016-01-01

The over-expressed colonic brain-derived neurotrophic factor (BDNF) has been reported to be associated with abdominal pain in patients with irritable bowel syndrome (IBS). However, the neuropathological mechanism is unclear. We here investigated the involvement of enteroglial cells (EGCs) and enteric nerves in IBS-like visceral hypersensitivity. We showed that glial fibrillary acidic protein (GFAP), tyrosine receptor kinase B (TrkB) and substance P (SP) were significantly increased in the colonic mucosa of IBS patients. The upregulation of those proteins was also observed in the colon of mice with visceral hypersensitivity, but not in the colon of BDNF+/− mice. Functionally, TrkB or EGC inhibitors, or BDNF knockdown significantly suppressed visceral hypersensitivity in mice. Using the EGC cell line, we found that recombinant human BDNF (r-HuBDNF) could directly activate EGCs via the TrkB-phospholipase Cγ1 pathway, thereby inducing a significant upregulation of SP. Moreover, supernatants from r-HuBDNF-activated EGC culture medium, rather than r-HuBDNF alone, triggered markedly augmented discharges in isolated intestinal mesenteric afferent nerves. r-HuBDNF alone could cause mesenteric afferent mechanical hypersensitivity independently, and this effect was synergistically enhanced by activated EGCs. We conclude that EGC-enteric nerve unit may be involved in IBS-like visceral hypersensitivity, and this process is likely initiated by BDNF-TrkB pathway activation. PMID:26837784

30 CFR 57.22217 - Seals and stoppings (I-A, I-B, and I-C mines).

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Seals and stoppings (I-A, I-B, and I-C mines... NONMETAL MINES Safety Standards for Methane in Metal and Nonmetal Mines Ventilation § 57.22217 Seals and stoppings (I-A, I-B, and I-C mines). All seals, and those stoppings that separate main intake from main...

30 CFR 57.22217 - Seals and stoppings (I-A, I-B, and I-C mines).

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Seals and stoppings (I-A, I-B, and I-C mines... NONMETAL MINES Safety Standards for Methane in Metal and Nonmetal Mines Ventilation § 57.22217 Seals and stoppings (I-A, I-B, and I-C mines). All seals, and those stoppings that separate main intake from main...

High heating rate thermal desorption for molecular surface sampling

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

Ovchinnikova, Olga S.; Van Berkel, Gary J.

2016-03-29

A method for analyzing a sample having at least one analyte includes the step of heating the sample at a rate of at least 10.sup.6 K/s to thermally desorb at least one analyte from the sample. The desorbed analyte is collected. The analyte can then be analyzed.

Isolation and functional characterization of TIF-IB, a factor that confers promoter specificity to mouse RNA polymerase I.

PubMed

Schnapp, A; Clos, J; Hädelt, W; Schreck, R; Cvekl, A; Grummt, I

1990-03-25

The murine ribosomal gene promoter contains two cis-acting control elements which operate in concert to promote efficient and accurate transcription initiation by RNA polymerase I. The start site proximal core element which is indispensable for promoter recognition by RNA polymerase I (pol I) encompasses sequences from position -39 to -1. An upstream control element (UCE) which is located between nucleotides -142 and -112 stimulates the efficiency of transcription initiation both in vivo and in vitro. Here we report the isolation and functional characterization of a specific rDNA binding protein, the transcription initiation factor TIF-IB, which specifically interacts with the core region of the mouse ribosomal RNA gene promoter. Highly purified TIF-IB complements transcriptional activity in the presence of two other essential initiation factors TIF-IA and TIF-IC. We demonstrate that the binding efficiency of purified TIF-IB to the core promoter is strongly enhanced by the presence in cis of the UCE. This positive effect of upstream sequences on TIF-IB binding is observed throughout the purification procedure suggesting that the synergistic action of the two distant promoter elements is not mediated by a protein different from TIF-IB. Increasing the distance between both control elements still facilitates stable factor binding but eliminates transcriptional activation. The results demonstrate that TIF-IB binding to the rDNA promoter is an essential early step in the assembly of a functional transcription initiation complex. The subsequent interaction of TIF-IB with other auxiliary transcription initiation factors, however, requires the correct spacing between the UCE and the core promoter element.

Thrust Slip Rates as a Control on the Presence and Spatial Distribution of High Metamorphic Heating Rates in Collisional Systems: The "Hot Iron" Model Revisited

NASA Astrophysics Data System (ADS)

Thigpen, R.; Ashley, K. T.; Law, R. D.; Mako, C. A.

2017-12-01

In natural systems, two key observations indicate that major strain discontinuities such as faults and shear zones should play a fundamental role in orogenic thermal evolution: (1) Large faults and shear zones often separate components of the composite orogen that have experienced broadly different thermal and deformational histories, and (2) quantitative metamorphic and diffusional studies indicate that heating rates are much faster and the duration of peak conditions much shorter in natural collisional systems than those predicted by numerical continuum deformation models. Because heat transfer processes such as conduction usually operate at much slower time scales than rates of other tectonic processes, thermal evolution is often transient and thus can be strongly influenced by tectonic disturbances that occur at rates much faster than thermal relaxation. Here, we use coupled thermal-mechanical finite element models of thrust faults to explore how fault slip rate may fundamentally influence the thermal evolution of individual footwall and hanging wall thrust slices. The model geometry involves a single crustal-scale thrust with a dip of 25° that is translated up the ramp at average velocities of 20, 35, and 50 km Myr-1, interpreted to represent average to relatively high slip rates observed in many collisional systems. Boundary conditions include crustal radioactive heat production, basal mantle heat flow, and surface erosion rates that are a function of thrust rate and subsequent topography generation. In the models, translation of the hanging wall along the crustal-scale detachment results in erosion, exhumation, and retrograde metamorphism of the emerging hanging wall topography and coeval burial, `hot iron' heating, and prograde metamorphism of the thrust footwall. Thrust slip rates of 20, 35, and 50 km Myr-1 yield maximum footwall heating rates ranging from 55-90° C Myr-1 and maximum hanging wall cooling rates of 138-303° C Myr-1. These relatively rapid

Optimum spectral resolution for computing atmospheric heating and photodissociation rates

NASA Astrophysics Data System (ADS)

Stamnes, K.; Tsay, S.-C.

1990-06-01

Rapid, reliable and accurate computations of atmospheric heating rates are needed in climate models aimed at predicting the impact of greenhouse gases on the surface temperature. Photolysis rates play a major role in photochemical models used to assess potential changes in atmospheric ozone abundance due to man's release of chlorofluorocarbons. Both rates depend directly on the amount of solar radiation available at any level in the atmosphere. We present a very efficient method of computing these rates in which integration over the solar spectrum is reduced to a minimum number of monochromatic (or pseudogray) problems by appealing to the continuum features of the ozone absorption cross-sections. To explore the resolutions needed to obtain adequate results we have divided the spectral range between 175 and 700 nm into four regions. Within each of these regions we may vary the resolution as we wish. Accurate results are obtained for very coarse spectral resolution provided all cross-sections are averaged by weighting them with the solar flux across any bin. By using this procedure we find that heating rate errors are less than 20% for all altitudes when only four spectral bands across the entire wavelength region from 175 to 700 nm are used to compute the heating rate profile. Similarly, we find that the error in the photodissociation of ozone is less than a few percent when 10 nm resolution is used in the Hartley and Huggins bands (below 330 nm), while an average over the entire wavelength region from 400 to 700 nm yields similar accuracy for the Chappuis band. For integrated u.v. dose estimates a resolution slightly better than 10 nm is required in the u.v.B region (290-315 nm) to yield an accuracy better than 10%, but we may treat the u.v.A region (315-400 nm) as a single band and yet have an accuracy better than 2%.

Does attenuated skin blood flow lower sweat rate and the critical environmental limit for heat balance during severe heat exposure?

PubMed

Cramer, Matthew N; Gagnon, Daniel; Crandall, Craig G; Jay, Ollie

2017-02-01

What is the central question of this study? Does attenuated skin blood flow diminish sweating and reduce the critical environmental limit for heat balance, which indicates maximal heat loss potential, during severe heat stress? What is the main finding and its importance? Isosmotic hypovolaemia attenuated skin blood flow by ∼20% but did not result in different sweating rates, mean skin temperatures or critical environmental limits for heat balance compared with control and volume-infusion treatments, suggesting that the lower levels of skin blood flow commonly observed in aged and diseased populations may not diminish maximal whole-body heat dissipation. Attenuated skin blood flow (SkBF) is often assumed to impair core temperature (T c ) regulation. Profound pharmacologically induced reductions in SkBF (∼85%) lead to impaired sweating, but whether the smaller attenuations in SkBF (∼20%) more often associated with ageing and certain diseases lead to decrements in sweating and maximal heat loss potential is unknown. Seven healthy men (28 ± 4 years old) completed a 30 min equilibration period at 41°C and a vapour pressure (P a ) of 2.57 kPa followed by incremental steps in P a of 0.17 kPa every 6 min to 5.95 kPa. Differences in heat loss potential were assessed by identifying the critical vapour pressure (P crit ) at which an upward inflection in T c occurred. The following three separate treatments elicited changes in plasma volume to achieve three distinct levels of SkBF: control (CON); diuretic-induced isosmotic dehydration to lower SkBF (DEH); and continuous saline infusion to maintain SkBF (SAL). The T c , mean skin temperature (T sk ), heart rate, mean laser-Doppler flux (forearm and thigh; LDF mean ), mean local sweat rate (forearm and thigh; LSR mean ) and metabolic rate were measured. In DEH, a 14.2 ± 5.7% lower plasma volume resulted in a ∼20% lower LDF mean in perfusion units (PU) (DEH, 139 ± 23 PU; CON, 176 ± 22 PU; and SAL

BK polyomavirus genotypes Ia and Ib1 exhibit different biological properties in renal transplant recipients.

PubMed

Varella, Rafael B; Zalona, Ana Carolina J; Diaz, Nuria C; Zalis, Mariano G; Santoro-Lopes, Guilherme

2018-01-02

BK polyomavirus (BKV) is an opportunist agent associated with nephropathy (BKVAN) in 1-10% of kidney transplant recipients. BKV is classified into genotypes or subgroups according to minor nucleotidic variations with unknown biological implications. Studies assessing the possible association between genotypes and the risk of BKVAN in kidney transplant patients have presented conflicting results. In these studies, genotype Ia, which is highly prevalent in Brazil, was less frequently found and, thus, comparative data on the biological properties of this genotype are lacking. In this study, BKV Ia and Ib1 genotypes were compared according to their viral load, genetic evolution (VP1 and NCCR) - in a cohort of renal transplant recipients. The patients infected with Ia (13/23; 56.5%) genotype exhibited higher viral loads in urine [>1.4 log over Ib1 (10/23; 43.5%); p=0.025]. In addition, genotype Ia was associated with diverse mutations at VP1 loops and sites under positive selection outside loops, which were totally absent in Ib1. Although the number of viremic patients was similar, the three patients who had BK nephropathy (BKVAN) were infected with Ia genotype. NCCR architecture (ww or rr) were not distinctive between Ia and Ib1 genotypes. Ia genotype, which is rare in other published BKV cohorts, presented some diverse biological properties in transplanted recipients in comparison to Ib1. Copyright © 2017 Elsevier B.V. All rights reserved.

Finally, the Progenitor of the Type Ib iPTF13bvn

NASA Astrophysics Data System (ADS)

Van Dyk, Schulyer

2017-08-01

Supernovae (SNe) are among the most powerful events in the Universe and have a profound influence on galaxy evolution. Whereas we have been able to identify the luminous red supergiant progenitor stars of the most common core-collapse explosions, the hydrogen-rich Type II, the progenitors of hydrogen-poor Type Ib and Type Ic have been far more elusive. To strip away a SN Ib/c progenitor's outer layers, theoretical models with either (a) a highly-massive star with prodigious winds during the Wolf-Rayet phase or (b) a somewhat lower-mass star in a close, mass-exchange binary system have been proposed. One example exists so far of a progenitor identification, for the SN Ib iPTF13bvn in NGC 5806. Both models have been invoked to explain this event, although most evidence to date points toward the binary model. Our combined team observed this SN with WFC3 in Cycle 22, about 2 years after explosion, to investigate whether the progenitor had disappeared. As a result, we were able to report that indeed it had. We also attempted to better characterize the nature of the progenitor by subtracting our images from the pre-explosion HST data. Unfortunately, the old SN was apparently still conspicuously present. We therefore propose to reimage the SN site, when the SN should then be well below detectability, to produce high-quality templates of the host galaxy for subtraction. We can then finally fully reveal the progenitor and understand its true nature. iPTF13bvn is one of the most important historical SNe and will most probably be the best available case of a SN Ib progenitor for HST's remaining lifetime. It is imperative to understand the nature of this SN and its progenitor object.

OUTLINE OF MATHEMATICS - LEVELS I-A AND I-B FOR TALENT PRESERVATION CLASSES IN GRADE SEVEN.

ERIC Educational Resources Information Center

Houston Public Schools, TX.

LEVEL I-A UNIT AREAS COVER THE MEANING OF "NUMBER," ADDITION, MULTIPLICATION, SUBTRACTION, AND DIVISION. LEVEL I-B COVERS INTRODUCTION TO COMMON FRACTIONS, COMBINING FRACTION, FRACTIONAL PARTS, SEPARATING FRACTIONS, AND APPLICATIONS. EACH UNIT UNDER I-B HAS SUBDIVISIONS, WITH A PARAGRAPH OF TEACHING HINTS AND EXAMPLES. STRESS IS UPON…

Randomized clinical trial on the effect of a multispecies probiotic on visceroperception in hypersensitive IBS patients.

PubMed

Ludidi, S; Jonkers, D M; Koning, C J; Kruimel, J W; Mulder, L; van der Vaart, I B; Conchillo, J M; Masclee, A A M

2014-05-01

Irritable bowel syndrome (IBS) is characterized by heterogeneous pathophysiology and low response to treatment. Up to 60% of IBS patients suffers from visceral hypersensitivity, which is associated with symptom severity and underlying pathophysiological mechanisms. Recently, positive effects of probiotics in IBS have been reported, but overall the response was modest. We performed a study in IBS patients, characterized by visceral hypersensitivity measured with the rectal barostat, aiming to assess the effect of 6 weeks of multispecies probiotic mix on visceral pain perception. We conducted a randomized, placebo-controlled, double-blind trial in forty Rome III IBS patients with visceral hypersensitivity. Prior to intake, patients kept a 2-week symptom diary and underwent a rectal barostat measurement. When hypersensitivity was confirmed, participation was allowed and patients received a multispecies probiotic with in vitro proven potential beneficial effects on mechanisms contributing to visceral hypersensitivity (six different probiotic strains; 10(9)  cfu/g), or a placebo product of one sachet (5 g) per day for 6 weeks. At the end of the intervention period, visceroperception and symptoms were reassessed. Thirty-five patients completed the trial. The percentage of patients with visceral hypersensitivity decreased significantly in the probiotic and placebo group (76.5% and 71.4%, respectively; N.S. between groups). Improvement in pain scores and mean symptom score did not differ between the probiotic and placebo group. In this placebo-controlled trial in IBS patients with visceral hypersensitivity, no significant effect of a multispecies probiotic on viscerperception was observed. The study has been registered in the US National Library of Medicine (http://www.clinicaltrials.gov, NCT00702026). © 2014 John Wiley & Sons Ltd.

Neuroimmune interactions at different intestinal sites are related to abdominal pain symptoms in children with IBS.

PubMed

Di Nardo, G; Barbara, G; Cucchiara, S; Cremon, C; Shulman, R J; Isoldi, S; Zecchi, L; Drago, L; Oliva, S; Saulle, R; Barbaro, M R; Stronati, L

2014-02-01

Neuroimmune interactions and inflammation have been proposed as factors involved in sensory-motor dysfunction and symptom generation in adult irritable bowel syndrome (IBS) patients. In children with IBS and healthy controls, we measured ileocolonic mast cell infiltration and fecal calprotectin and evaluated the relationships between these parameters and abdominal pain symptoms and stooling pattern. Irritable bowel syndrome patients diagnosed according to Pediatric Rome III criteria and healthy controls kept a 2-week pain/stooling diary. Ileocolonic mucosal mast cells (MC) and MC in close proximity to nerve fibers (MC-NF) were identified immunohistochemically and quantified. Fecal calprotectin concentration was measured. 21 IBS patients and 10 controls were enrolled. The MC-NF count was significantly higher in the ileum (p = 0.01), right colon (p = 0.04), and left colon (p < 0.001) of IBS patients compared with controls. No differences in fecal calprotectin concentration were noted. Abdominal pain intensity score correlated with ileal MC count (r(s) = 0.47, p = 0.030) and right colon MC-NF count (r(s) = 0.52, p = 0.015). In addition, children with IBS with >3 abdominal pain episodes/week had greater ileal (p = 0.002) and right colonic (p = 0.01) MC counts and greater ileal (p = 0.05) and right colonic (p = 0.016) MC-NF counts than children with less frequent pain. No relationship was found between MC and MC-NF and fecal calprotectin or stooling pattern. Mast cells-nerve fibers counts are increased in the ileocolonic mucosa of children with IBS. Mast cells and MC-NF counts are related to the intensity and frequency of abdominal pain. © 2013 John Wiley & Sons Ltd.

Nonclassical MHC Ib-restricted CD8+ T Cells Recognize Mycobacterium tuberculosis-Derived Protein Antigens and Contribute to Protection Against Infection

PubMed Central

Shang, Shaobin; Siddiqui, Sarah; Bian, Yao; Zhao, Jie; Wang, Chyung-Ru

2016-01-01

MHC Ib-restricted CD8+ T cells have been implicated in host defense against Mycobacterium tuberculosis (Mtb) infection. However, the relative contribution of various MHC Ib-restricted T cell populations to anti-mycobacterial immunity remains elusive. In this study, we used mice that lack MHC Ia (Kb-/-Db-/-), MHC Ia/H2-M3 (Kb-/-Db-/-M3-/-), or β2m (β2m-/-) to study the role of M3-restricted and other MHC Ib-restricted T cells in immunity against Mtb. Unlike their dominant role in Listeria infection, we found that M3-restricted CD8+ T cells only represented a small proportion of the CD8+ T cells responding to Mtb infection. Non-M3, MHC Ib-restricted CD8+ T cells expanded preferentially in the lungs of Mtb-infected Kb-/-Db-/-M3-/- mice, exhibited polyfunctional capacities and conferred protection against Mtb. These MHC Ib-restricted CD8+ T cells recognized several Mtb-derived protein antigens at a higher frequency than MHC Ia-restricted CD8+ T cells. The presentation of Mtb antigens to MHC Ib-restricted CD8+ T cells was mostly β2m-dependent but TAP-independent. Interestingly, a large proportion of Mtb-specific MHC Ib-restricted CD8+ T cells in Kb-/-Db-/-M3-/- mice were Qa-2-restricted while no considerable numbers of MR1 or CD1-restricted Mtb-specific CD8+ T cells were detected. Our findings indicate that nonclassical CD8+ T cells other than the known M3, CD1, and MR1-restricted CD8+ T cells contribute to host immune responses against Mtb infection. Targeting these MHC Ib-restricted CD8+ T cells would facilitate the design of better Mtb vaccines with broader coverage across MHC haplotypes due to the limited polymorphism of MHC class Ib molecules. PMID:27272249

Heat transfer rate within non-spherical thick grains

NASA Astrophysics Data System (ADS)

Huchet, Florian; Richard, Patrick; Joniot, Jules; Le Guen, Laurédan

2017-06-01

The prediction of the internal heat conduction into non-spherical thick grains constitutes a significant issue for physical modeling of a large variety of application involving convective exchanges between fluid and grains. In that context, the present paper deals with heat rate measurements of various sizes of particles, the thermal sensors being located at the interface fluid/grain and into the granular materials. Their shape is designed as cuboid in order to control the surface exchanges. In enclosed coneshaped apparatus, a sharp temperature gradient is ensured from a hot source releasing the air stream temperature equal to about 400°C. Two orientations of grain related to the air stream are considered: diagonally and straight arrangements. The thermal diffusivity of the grains and the Biot numbers are estimated from an analytical solution established for slab. The thermal kinetics evolution is correlated to the sample granular mass and its orientation dependency is demonstrated. Consequently, a generalized scaling law is proposed which is funded from the effective area of the heat transfer at the grain-scale, the dimensionless time being defined from the calculated diffusional coefficients.

Lactulose breath test gas production in childhood IBS is associated with intestinal transit and bowel movement frequency

USDA-ARS?s Scientific Manuscript database

In adults with irritable bowel syndrome (IBS), bacterial gas production (colonic fermentation) is related to both symptom generation and intestinal transit. Whether gas production affects symptom generation, psychosocial distress, or intestinal transit in childhood IBS is unknown. Children (ages 7-1...

Aerodynamic pressures and heating rates on surfaces between split elevons at Mach 6.6

NASA Technical Reports Server (NTRS)

Hunt, L. Roane

1988-01-01

An aerothermal study was performed in the Langley 8-Foot High Temperature Tunnel at Mach number 6.6 to define the pressures and heating rates on the surfaces between split elevons similar to those used on the Space Shuttle. Tests were performed with both laminar and turbulent boundary layers on the wing surface upstream of the elevons. The flow in the chordwise gap between the elevons was characterized by flow separation at the gap entrance and flow reattachment at a depth into the gap inversely proportional to the gap width. The gap pressure and heating rate increased significantly with decrease of elevon gap width, and the maximum gap heating rate was proportional to the maximum gap pressure. Correlation of the present results indicate that the gap heating was directly proportional to the elevon windward surface pressure and was not dependent upon whether the boundary layer on the windward elevon surface was laminar or turbulent.

Extreme learning machine: a new alternative for measuring heat collection rate and heat loss coefficient of water-in-glass evacuated tube solar water heaters.

PubMed

Liu, Zhijian; Li, Hao; Tang, Xindong; Zhang, Xinyu; Lin, Fan; Cheng, Kewei

2016-01-01

Heat collection rate and heat loss coefficient are crucial indicators for the evaluation of in service water-in-glass evacuated tube solar water heaters. However, the direct determination requires complex detection devices and a series of standard experiments, wasting too much time and manpower. To address this problem, we previously used artificial neural networks and support vector machine to develop precise knowledge-based models for predicting the heat collection rates and heat loss coefficients of water-in-glass evacuated tube solar water heaters, setting the properties measured by "portable test instruments" as the independent variables. A robust software for determination was also developed. However, in previous results, the prediction accuracy of heat loss coefficients can still be improved compared to those of heat collection rates. Also, in practical applications, even a small reduction in root mean square errors (RMSEs) can sometimes significantly improve the evaluation and business processes. As a further study, in this short report, we show that using a novel and fast machine learning algorithm-extreme learning machine can generate better predicted results for heat loss coefficient, which reduces the average RMSEs to 0.67 in testing.

Preinduction of heat shock protein 70 protects mice against post-infection irritable bowel syndrome via NF-κB and NOS/NO signaling pathways.

PubMed

Zhou, Xuchun; Dong, Liwei; Yang, Bo; He, Zhoutao; Chen, Yiyao; Deng, Taozhi; Huang, Baili; Lan, Cheng

2015-12-01

This study aimed to investigate the protective effects of preinduction of heat shock protein 70 (HSP70) on Trichinella spiralis infection-induced post-infectious irritable bowel syndrome (PI-IBS) in mice. Trichinella spiralis infection significantly reduced HSP70 abundance, ileal villus height and crypt depth, expression of tight junctions, serum lysine and arginine concentrations, and ileal SCL7A6 and SCL7A7 mRNA levels, induced inflammatory response, and activated NF-κB signaling pathway. Meanwhile, the heat treatment upregulated HSP70 expression, and then reversed intestinal dysfunction and inflammatory response. Preinduction of HSP70 enhanced serum arginine and intestinal SCL7A7 expression and inhibited NF-κB activation compared with PI-IBS model. Treatment with pyrrolidine dithiocarbamate (PDTC, an NF-κB inhibitor) and N-nitro-L-arginine methyl ester hydrochloride (L-NAME, a nitric oxide synthase inhibitor, NOS) further demonstrated that preinduction of HSP70 might inhibit NF-κB and activated NOS/nitric oxide (NO) signaling pathways. In conclusion, preinduction of HSP70 by heat treatment may confer beneficial effects on Trichinella spiralis infection-induced PI-IBS in mice, and the protective effect of HSP70 may be associated with inhibition of NF-κB and stimulation of NOS/NO signaling pathways.

SP industry calorimeter for rate of heat release measurements up to 10MW

NASA Astrophysics Data System (ADS)

Dahlberg, Martin

The Swedish National Testing and Research Institute (SP) has installed a 10 MW fire calorimeter for rate of heat release measurements, similar to the one at Factory Mutual Research Corporation (FMRC). It can be used to classify commodities with respect to their fire hazard, to evaluate the efficiency of sprinkler systems, for chemical analysis of the combustion gases from hazardous fires, to produce input data for the fire modelling, etc. A large hood collects the fire gases and leads them into a duct where gas velocity, gas temperature, smoke density, and contents of oxygen, carbon dioxide, and carbon monoxide are measured. On the basis of these measurements, mass flow and rate of heat release are calculated. The rate of heat release is calculated according to the oxygen consumption principle. The upper limit for measurements is approximately 10 MW and the lower is 0.1 MW.

Neoadjuvant chemotherapy followed by surgery has no therapeutic advantages over concurrent chemoradiotherapy in International Federation of Gynecology and Obstetrics stage IB-IIB cervical cancer.

PubMed

Lee, Jeongshim; Kim, Tae Hyung; Kim, Gwi Eon; Keum, Ki Chang; Kim, Yong Bae

2016-09-01

We aimed to assess the efficacy of neoadjuvant chemotherapy followed by surgery (NACT+S), and compared the clinical outcome with that of concurrent chemoradiotherapy (CCRT) in patients with International Federation of Gynecology and Obstetrics (FIGO) IB-IIB cervical cancer. We reviewed 85 patients with FIGO IB-IIB cervical cancer who received NACT+S between 1989 and 2012, and compared them to 358 control patients who received CCRT. The clinical application of NACT was classified based on the following possible therapeutic benefits: increasing resectability after NACT by reducing tumor size or negative conversion of node metastasis; downstaging adenocarcinoma regarded as relatively radioresistant; and preservation of fertility through limited surgery after NACT. Of 85 patients in the NACT+S group, the pathologic downstaging and complete response rates were 68.2% and 22.6%, respectively. Only two young patients underwent limited surgery for preservation of fertility. Patients of the NACT+S group were younger, less likely to have node metastasis, and demonstrated a higher proportion of FIGO IB cases than those of the CCRT group (p≤0.001). The 5-year locoregional control, progression-free survival, and overall survival rates in the NACT+S group were 89.7%, 75.6%, and 92.1%, respectively, which were not significantly different from the rates of 92.5%, 74%, and 84.9% observed in the CCRT group, respectively (p>0.05). NACT+S has no therapeutic advantages over CCRT, the standard treatment. Therefore, NACT+S should be considered only in selected patients through multidisciplinary discussion or clinical trial setting.

Decreased miR-199 augments visceral pain in patients with IBS through translational upregulation of TRPV1.

PubMed

Zhou, QiQi; Yang, Liuqing; Larson, Scott; Basra, Sapreet; Merwat, Shehzad; Tan, Alai; Croce, Carlo; Verne, G Nicholas

2016-05-01

Many patients with irritable bowel syndrome IBS not only have abdominal pain but also may suffer from visceral hypersensitivity and heighted visceral nociception. Moreover, IBS has few effective therapeutic agents and mechanisms of disease are unclear. Our goals were to (i) identify microRNA (miRNA) expression, signalling and targets in human colon (controls; patients with IBS); (ii) verify in vitro, IBS-associated changes in miRNAs, especially miR-199, which is complementary to the transient receptor potential vanilloid type 1 (TRPV1) gene; and (iii) determine whether modulating the expression of miRNAs in vivo, especially miR-199, reverses associated changes and pathological hallmarks of visceral hypersensitivity via TRPV1 signalling. We evaluated 45 patients with diarrhoea-predominant IBS (IBS-D) and 40 controls with (1) visceral pain severity score and (2) colonoscopy with biopsies. miRNA expression was evaluated in human colon following miRNA array analysis. Luciferase assays were done to confirm relationships between miR-199 and TRPV1 expression. A rat model of visceral hypersensitivity was used to study miR-199 and its target gene (TRPV1) expression in dorsal root ganglion (DRG) and colon in vivo. Gut miR-199a/b expression in IBS-D was significantly decreased, which correlated directly with both increased visceral pain scores and TRPV1 expression. In vivo upregulation of miR-199a by intraperitoneal injection of lenti-miR-199a precursors decreased visceral hypersensitivity via diminished TRPV1 signalling. Decreased colonic miR-199a/b correlates with visceral pain in patients with IBS-D. Similarly, reduced miR-199a expression in rat DRG and colon tissue is associated with heightened visceral hypersensitivity. In vivo upregulation of miR-199a decreases visceral pain via inhibition of TRPV1 signalling. Thus, miR-199 precursors may be promising therapeutic candidates for the treatment in patients with visceral pain. Published by the BMJ Publishing Group Limited

Sham acupuncture is as efficacious as true acupuncture for the treatment of IBS: A randomized placebo controlled trial.

PubMed

Lowe, C; Aiken, A; Day, A G; Depew, W; Vanner, S J

2017-07-01

Irritable bowel syndrome (IBS) patients increasingly seek out acupuncture therapy to alleviate symptoms, but it is unclear whether the benefit is due to a treatment-specific effect or a placebo response. This study examined whether true acupuncture is superior to sham acupuncture in relieving IBS symptoms and whether benefits were linked to purported acupuncture mechanisms. A double blind sham controlled acupuncture study was conducted with Rome I IBS patients receiving twice weekly true acupuncture for 4 weeks (n=43) or sham acupuncture (n=36). Patients returned at 12 weeks for a follow-up review. The primary endpoint of success as determined by whether patients met or exceeded their established goal for percentage symptom improvement. Questionnaires were completed for symptom severity scores, SF-36 and IBS-36 QOL tools, McGill pain score, and Pittsburg Sleep Quality Index. A subset of patients underwent barostat measurements of rectal sensation at baseline and 4 weeks. A total of 53% in the true acupuncture group met their criteria for a successful treatment intervention, but this did not differ significantly from the sham group (42%). IBS symptom scores similarly improved in both groups. Scores also improved in the IBS-36, SF-36, and the Pittsburg Sleep Quality Index, but did not differ between groups. Rectal sensory thresholds were increased in both groups following treatment and pain scores decreased; however, these changes were similar between groups. The lack of differences in symptom outcomes between sham and true treatment acupuncture suggests that acupuncture does not have a specific treatment effect in IBS. © 2017 John Wiley & Sons Ltd.

Cytokine Response after Stimulation with Key Commensal Bacteria Differ in Post-Infectious Irritable Bowel Syndrome (PI-IBS) Patients Compared to Healthy Controls.

PubMed

Sundin, Johanna; Rangel, Ignacio; Repsilber, Dirk; Brummer, Robert-Jan

2015-01-01

Microbial dysbiosis and prolonged immune activation resulting in low-grade inflammation and intestinal barrier dysfunction have been suggested to be underlying causes of post-infectious irritable bowel syndrome (PI-IBS). The aim of this study was to evaluate the difference in cytokine response between mucosal specimens of PI-IBS patients and healthy controls (HC) after ex vivo stimulation with key anaerobic bacteria. Colonic biopsies from 11 PI-IBS patients and 10 HC were stimulated ex vivo with the commensal bacteria Bacteroides ovatus, Ruminococcus gnavus, Akkermansia muciniphila, Subdoligranulum variabile and Eubacterium limosum, respectively. The cytokine release (IL-1β, IL-2, IL-8, IL-10, IL-13, IL-17, TNF-α and IFN-γ) in stimulation supernatants was analyzed using the LUMINEX assay. Comparison of cytokine release between PI-IBS patients and healthy controls was performed taking both unstimulated and bacterially stimulated mucosal specimens into account. IL-13 release from mucosal specimens without bacterial stimulation was significantly lower in PI-IBS patients compared to HC (p < 0.05). After stimulation with Subdoligranulum variabile, IL-1β release from PI-IBS patients was significantly increased compared to HC (p < 0.05). Stimulation with Eubacterium limosum resulted in a significantly decreased IL-10 release in HC compared to PI-IBS patients (p < 0.05) and a tendency to decreased IL-13 release in HC compared to PI-IBS patients (p = 0.07). PI-IBS patients differ from HC with regard to cytokine release ex vivo after stimulation with selected commensal bacteria. Hence, our results support that the pathogenesis of PI-IBS comprises an altered immune response against commensal gut microbes.

MiR-144 Increases Intestinal Permeability in IBS-D Rats by Targeting OCLN and ZO1.

PubMed

Hou, Qiuke; Huang, Yongquan; Zhu, Shuilian; Li, Peiwu; Chen, Xinlin; Hou, Zhengkun; Liu, Fengbin

2017-01-01

Irritable bowel syndrome with diarrhoea (IBS-D) is a chronic, functional bowel disorder characterized by abdominal pain or diarrhoea and altered bowel habits, which correlate with intestinal hyperpermeability. MicroRNAs (miRNAs) are involved in regulating intestinal permeability in IBS-D. However, the role of miRNAs in regulating intestinal permeability and protecting the epithelial barrier remains unclear. Our goals were to (i) identify differential expression of miRNAs and their targets in the distal colon of IBS-D rats; (ii) verify in vitro whether occludin (OCLN) and zonula occludens 1 (ZO1/TJP1) were direct targets of miR-144 and were down-regulated in IBS-D rats; and (iii) determine whether down-regulation of miR-144 in vitro could reverse the pathological hallmarks of intestinal hyperpermeability via targeting OCLN and ZO1. The IBS-D rat model was established using 4% acetic acid and evaluated by haematoxylin-eosin (HE) staining. The distal colon was obtained in order to perform miRNA microarray analysis and to isolate and culture colonic epithelial cells. When differential expression of miRNA was found, the results were verified by qRT-PCR, and the target genes were further explored by bioinformatics analysis. Correlation analyses were carried out to compare the expression of miRNA and target genes. Then, mutants, miRNA mimics and inhibitors of the target genes were constructed and transfected to colonic epithelial cells. qRT-PCR, western blotting, enzyme-linked immunosorbent assays (ELISAs) and dual-luciferase assays were used to investigate the expression of miR-144 and OCLN, ZO1 in IBS-D rats. There were 8 up-regulated and 18 down-regulated miRNAs identified in the IBS-D rat model. Of these, miR-144 was markedly up-regulated and resulted in the down-regulation of OCLN and ZO1 expression. Overexpression of miR-144 by transfection of miR-144 precursor markedly inhibited the expression of OCLN and ZO1. Further studies confirmed that OCLN and ZO1 were direct

Analysis of Water Recovery Rate from the Heat Melt Compactor

NASA Technical Reports Server (NTRS)

Balasubramaniam, R.; Hegde, U.; Gokoglu, S.

2013-01-01

any remaining free water in the trash by evaporation. The temperature settings of the heated surfaces are usually kept above the saturation temperature of water but below the melting temperature of the plastic in the waste during this step to avoid any encapsulation of wet trash which would reduce the amount of recovered water by blocking the vapor escape. In this paper, we analyze the water recovery rate during Phase B where the trash is heated and water leaves the waste chamber as vapor, for operation of the HMC in reduced gravity. We pursue a quasi-one-dimensional model with and without sidewall heating to determine the water recovery rate and the trash drying time. The influences of the trash thermal properties, the amount of water loading, and the distribution of the water in the trash on the water recovery rates are determined.

Three-dimensional Monte Carlo calculation of atmospheric thermal heating rates

NASA Astrophysics Data System (ADS)

Klinger, Carolin; Mayer, Bernhard

2014-09-01

We present a fast Monte Carlo method for thermal heating and cooling rates in three-dimensional atmospheres. These heating/cooling rates are relevant particularly in broken cloud fields. We compare forward and backward photon tracing methods and present new variance reduction methods to speed up the calculations. For this application it turns out that backward tracing is in most cases superior to forward tracing. Since heating rates may be either calculated as the difference between emitted and absorbed power per volume or alternatively from the divergence of the net flux, both approaches have been tested. We found that the absorption/emission method is superior (with respect to computational time for a given uncertainty) if the optical thickness of the grid box under consideration is smaller than about 5 while the net flux divergence may be considerably faster for larger optical thickness. In particular, we describe the following three backward tracing methods: the first and most simple method (EMABS) is based on a random emission of photons in the grid box of interest and a simple backward tracing. Since only those photons which cross the grid box boundaries contribute to the heating rate, this approach behaves poorly for large optical thicknesses which are common in the thermal spectral range. For this reason, the second method (EMABS_OPT) uses a variance reduction technique to improve the distribution of the photons in a way that more photons are started close to the grid box edges and thus contribute to the result which reduces the uncertainty. The third method (DENET) uses the flux divergence approach where - in backward Monte Carlo - all photons contribute to the result, but in particular for small optical thickness the noise becomes large. The three methods have been implemented in MYSTIC (Monte Carlo code for the phYSically correct Tracing of photons In Cloudy atmospheres). All methods are shown to agree within the photon noise with each other and with a

Effect of heating rate on thermal cracking characteristics and kinetics of Xinjiang oil sand bitumen by TG-FTIR

NASA Astrophysics Data System (ADS)

Hao, Junhui; Zhang, Jinhong; Qiao, Yingyun; Tian, Yuanyu

2017-08-01

This work was aimed to investigate effects of heating rate on thermal cracking behaviors, distribution of gaseous products and activation energy of the thermal cracking process of Xinjiang oil sand bitumen (OSB). The thermal cracking experiments of Xinjiang OSB were performed by using thermogravimetric analyzer (TGA) at various heating rates of 10, 20, 50, 80 and 120 K/min. The evolving characteristic of gaseous products produced from the thermal cracking process was evaluated by the Fourier transform infrared spectrometry (FTIR) connected with TG. The kinetic parameters of the thermal cracking process of Xinjiang OSB at each of heating rate were determined by the Coats-Redfern model. The result show that the temperature intervals of DE volatilization stage and main reaction stage, the ((dw/dt) max and Tmax in thermal cracking process of Xinjiang OSB all increased with the increasing heating rate. While the heating rate has not obvious effect on the coke yield of Xinjiang OSB. Furthermore, the maximum absorbance of gaseous products and corresponding temperature became larger as the heating rate increases. The activation energy of this two stage both presented increasing trend with the rising heating rate, while the increasing content of that of DE volatilization stage was weaker compared to that of main reaction stage.

Hexagonally ordered nanodots: Result of substrate rotation during oblique incidence low energy IBS

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

Chowdhury, Debasree, E-mail: debasree.chowdhury@saha.ac.in; Ghose, Debabrata, E-mail: debasree.chowdhury@saha.ac.in

The anisotropic regular patterns are often results during oblique incidence ion beam sputtering (IBS). Simultaneous substrate rotation (SR) during IBS can suppress surface roughening and removes anisotropic nature of surface pattern. Here, the evolution of Si surface morphology as result of with and without SR is studied during oblique incidence low energy Ar{sup +} sputtering. Resultant topography shows smooth surface to hexagonally ordered nanodots at different rotating conditions. Interestingly, surface roughness exhibits non-monotonic dependence on rotation frequency. The underlying mechanism for dot formation can be described within the framework of isotropic DKS equation.

Changes in ciprofloxacin resistance levels in Enterobacter aerogenes isolates associated with variable expression of the aac(6')-Ib-cr gene.

PubMed

Ruiz, Elena; Ocampo-Sosa, Alain A; Alcoba-Flórez, Julia; Román, Elena; Arlet, Guillaume; Torres, Carmen; Martínez-Martínez, Luis

2012-02-01

Two closely related Enterobacter aerogenes isolates presented a new identical aac(6')-Ib-cr genetic environment, including IS26. One isolate showed lower MICs of ciprofloxacin, norfloxacin, tobramycin, and amikacin and decreased expression of aac(6')-Ib-cr, which might be related to a 12-bp deletion causing a displacement of the -10 box upstream of the aac(6')-Ib-cr gene.

A Randomized Controlled Trial Comparing the Low FODMAP Diet vs. Modified NICE Guidelines in US Adults with IBS-D.

PubMed

Eswaran, Shanti L; Chey, William D; Han-Markey, Theresa; Ball, Sarah; Jackson, Kenya

2016-12-01

There has been an increasing interest in the role of fermentable oligo-, di-, and monosaccharides and polyols (FODMAPs) in irritable bowel syndrome (IBS). We report results from the first randomized controlled trial of the low FODMAP diet in US adults with IBS and diarrhea (IBS-D). The objectives were to compare the efficacy of the low FODMAP diet vs. a diet based upon modified National Institute for Health and Care Excellence guidelines (mNICE) on overall and individual symptoms in IBS-D patients. This was a single-center, randomized-controlled trial of adult patients with IBS-D (Rome III) which compared 2 diet interventions. After a 2-week screening period, eligible patients were randomized to a low FODMAP or mNICE diet for 4 weeks. The primary end point was the proportion of patients reporting adequate relief of IBS-D symptoms ≥50% of intervention weeks 3-4. Secondary outcomes included a composite end point which required response in both abdominal pain (≥30% reduction in mean daily pain score compared with baseline) and stool consistency (decrease in mean daily Bristol Stool Form of ≥1 compared with baseline), abdominal pain and stool consistency responders, and other key individual IBS symptoms assessed using daily questionnaires. After screening, 92 subjects (65 women, median age 42.6 years) were randomized. Eighty-four patients completed the study (45 low FODMAP, 39 mNICE). Baseline demographics, symptom severity, and nutrient intake were similar between groups. Fifty-two percent of the low FODMAP vs. 41% of the mNICE group reported adequate relief of their IBS-D symptoms (P=0.31). Though there was no significant difference in the proportion of composite end point responders (P=0.13), the low FODMAP diet resulted in a higher proportion of abdominal pain responders compared with the mNICE group (51% vs. 23%, P=0.008). Compared with baseline scores, the low FODMAP diet led to greater reductions in average daily scores of abdominal pain, bloating

Selection, Evaluation, and Rating of Compact Heat Exchangers v. 1.006

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

Carlson, Matthew D.

2016-11-09

SEARCH determines and optimizes the design of a compact heat exchanger for specified process conditions. The user specifies process boundary conditions including the fluid state and flow rate and SEARCH will determine the optimum flow arrangement, channel geometry, and mechanical design for the unit. Fluids are modeled using NIST Refprop or tabulated values. A variety of thermal-hydraulic correlations are available including user-defined equations to accurately capture the heat transfer and pressure drop behavior of the process flows.

Liquid-Phase Heat-Release Rates of the Systems Hydrazine-Nitric Acid and Unsymmetrical Dimethylhydrazine-Nitric Acid

NASA Technical Reports Server (NTRS)

Somogyi, Dezso; Feiler, Charles E.

1960-01-01

The initial rates of heat release produced by the reactions of hydrazine and unsymmetrical dimethylhydrazine with nitric acid were determined in a bomb calorimeter under conditions of forced mixing. Fuel-oxidant weight ratio and injection velocity were varied. The rate of heat release apparently depended on the interfacial area between the propellants. Above a narrow range of injection velocities representing a critical amount of interfacial area, the rates reached a maximum and were almost constant with injection velocity. The maximum rate for hydrazine was about 70 percent greater than that for unsymmetrical dimethylhydrazine. The total heat released did not vary with mixture ratio over the range studied.

Co-occurrence of IBS and symptoms of anxiety or depression, among Norwegian twins, is influenced by both heredity and intrauterine growth.

PubMed

Bengtson, May-Bente; Aamodt, Geir; Vatn, Morten H; Harris, Jennifer R

2015-02-05

Environmental and genetic factors contribute to variation in irritable bowel syndrome (IBS), anxiety and depression. Comorbidity between these disorders is high. A previous investigation of our population-based twin cohort revealed that low birth weight increased the risk for development of IBS, with environmental influences in utero as the most relevant contributing factor. We hypothesise that both intrauterine and genetic factors influence the co-occurrence of IBS and symptoms of anxiety and depression. A postal questionnaire sent to 12700 Norwegian twins born between 1967 and 1979 comprised a checklist of 31 illnesses and symptoms, including IBS and symptoms of anxiety and depression. The influence of genetic factors and intrauterine growth on comorbidity between these disorders were analysed in the full sample and compared to those based on only monozygotic (MZ) twin pairs discordant for IBS (95 pairs) in birth weight group < 2500 g and ≥ 2500 g. In the co-twin analyses restricted growth (birth weight < 2500 g) was significantly associated with anxiety and depression (average birth weight difference of 181.0 g (p <0.0001) and 249.9 g (p < 0.0001), respectively). The analysis of the full sample revealed that IBS was significantly associated with symptoms of anxiety (adjusted OR = 2.5, 95% CI: 1.9, 3.3) and depression (adjusted OR = 2.3. 95% CI: 1.8, 3.0). Analyses of MZ pairs discordant for IBS indicated significant associations between IBS and symptoms of anxiety (OR = 3.7, 95% CI: 1.3, 10.5) and between IBS and symptoms of depression (OR = 4.2, 95% CI: 1.7, 9.9) only in the birth weight group below 2500 g. Our findings suggest that genetic factors partly explain the association between IBS and symptoms of anxiety and depression. In the low range of birth weight (<2500 g), restricted fetal growth seems to be a common contributing factor to the co-occurrence between these disorders.

A modified Monte Carlo model for the ionospheric heating rates

NASA Technical Reports Server (NTRS)

Mayr, H. G.; Fontheim, E. G.; Robertson, S. C.

1972-01-01

A Monte Carlo method is adopted as a basis for the derivation of the photoelectron heat input into the ionospheric plasma. This approach is modified in an attempt to minimize the computation time. The heat input distributions are computed for arbitrarily small source elements that are spaced at distances apart corresponding to the photoelectron dissipation range. By means of a nonlinear interpolation procedure their individual heating rate distributions are utilized to produce synthetic ones that fill the gaps between the Monte Carlo generated distributions. By varying these gaps and the corresponding number of Monte Carlo runs the accuracy of the results is tested to verify the validity of this procedure. It is concluded that this model can reduce the computation time by more than a factor of three, thus improving the feasibility of including Monte Carlo calculations in self-consistent ionosphere models.

IbMADS1 (Ipomoea batatas MADS-box 1 gene) is Involved in Tuberous Root Initiation in Sweet Potato (Ipomoea batatas)

PubMed Central

Ku, Amy Tsu; Huang, Yi-Shiuan; Wang, Yu-Shu; Ma, Daifu; Yeh, Kai-Wun

2008-01-01

Background and Aims The tuberization mechanism of sweet potato (Ipomoea batatas) has long been studied using various approaches. Morphological data have revealed that the tuberizing events result from the activation of the cambium, followed by cell proliferation. However, uncertainties still remain regarding the regulators participating in this signal-transduction pathway. An attempt was made to characterize the role of one MADS-box transcription factor, which was preferentially expressed in sweet potato roots at the early tuberization stage. Methods A differential expression level of IbMADS1 (Ipomoea batatas MADS-box 1) was detected temporally and spatially in sweet potato tissues. IbMADS1 responses to tuberization-related hormones were assessed. In order to identify the evolutionary significance, the expression pattern of IbMADS1 was surveyed in two tuber-deficient Ipomoea relatives, I. leucantha and I. trifida, and compared with sweet potato. In functional analyses, potato (Solanum tuberosum) was employed as a heterologous model. The resulting tuber morphogenesis was examined anatomically in order to address the physiological function of IbMADS1, which should act similarly in sweet potato. Key Results IbMADS1 was preferentially expressed as tuberous root development proceeded. Its expression was inducible by tuberization-related hormones, such as jasmonic acid and cytokinins. In situ hybridization data showed that IbMADS1 transcripts were specifically distributed around immature meristematic cells within the stele and lateral root primordia. Inter-species examination indicated that IbMADS1 expression was relatively active in sweet potato roots, but undetectable in tuber-deficient Ipomoea species. IbMADS1-transformed potatoes exhibited tuber morphogenesis in the fibrous roots. The partial swellings along fibrous roots were mainly due to anomalous proliferation and differentiation in the xylem. Conclusions Based on this study, it is proposed that IbMADS1 is an

Myasthenia gravis in a patient affected by glycogen storage disease type Ib: a further manifestation of an increased risk for autoimmune disorders?

PubMed

Melis, D; Balivo, F; Della Casa, R; Romano, A; Taurisano, R; Capaldo, B; Riccardi, G; Monsurrò, M R; Parenti, G; Andria, G

2008-12-01

Glycogen storage disease type Ib (GSD Ib, OMIM 232220) is an inborn disorder of glucose metabolism, caused by mutations in the G6PT gene, encoding a glucose 6-phosphate transporter (G6PT). GSD Ib is mainly associated with fasting hypoglycaemia and hepatomegaly. Most GSD Ib patients also show neutropenia and neutrophil dysfunction and therefore are at risk of developing severe infections and inflammatory bowel disease (IBD). An increased risk for autoimmune disorders, such as thyroid autoimmunity and Crohn-like disease, has also been demonstrated, but no systematic study on the prevalence of autoimmune disorders in GSD Ib patients has ever been performed. We describe a 25-year-old patient affected by GSD Ib who developed 'seronegative' myasthenia gravis (MG), presenting with bilateral eyelid ptosis, diplopia, dysarthria, severe dysphagia, dyspnoea and fatigue. The repetitive stimulation of peripheral nerves test showed signs of exhaustion of neuromuscular transmission, particularly evident in the cranial area. Even in the absence of identifiable anti-acetylcholine receptor antibodies, seronegative MG is considered an autoimmune disorder and may be related to the disturbed immune function observed in GSD Ib patients.

Unraveling the structure of the variola topoisomerase IB-DNA complex: a possible new twist on smallpox therapy.

PubMed

Osheroff, Neil

2006-10-01

Smallpox is a serious and highly contagious disease that is caused by the variola virus. It is one of the most severe infectious human diseases known, with mortality rates as high as 30%. A successful worldwide vaccination program led to the eradication of smallpox in 1980. However, the high transmission rate of variola virus, coupled with the deadly nature of smallpox, makes this virus a potentially devastating weapon for bioterrorism. Currently, there is no specific treatment for smallpox. However, a recent article on the structure of a variola topoisomerase IB-DNA complex provides an intriguing starting point for the rational design of drugs with potential activity against smallpox.

Fitness-related differences in the rate of whole-body evaporative heat loss in exercising men are heat-load dependent.

PubMed

Lamarche, Dallon T; Notley, Sean R; Louie, Jeffrey C; Poirier, Martin P; Kenny, Glen P

2018-01-01

What is the central question of this study? Aerobic fitness modulates heat loss, but the heat-load threshold at which fitness-related differences in heat loss occur in young healthy men remains unclear. What is the main finding and its importance? We demonstrate using direct calorimetry that aerobic fitness modulates heat loss in a heat-load-dependent manner, with fitness-related differences occurring between young men who have low and high fitness when the heat load is ∼≥500 W. Although aerobic fitness has been known for some time to modulate heat loss, our findings define the precise heat-load threshold at which fitness-related differences occur. The effect of aerobic fitness (defined as rate of peak oxygen consumption) on heat loss during exercise is thought to be related to the level of heat stress. However, it remains unclear at what combined exercise and environmental (net) heat-load threshold these fitness-related differences occur. To identify this, we assessed whole-body heat exchange (dry and evaporative) by direct calorimetry in young (22 ± 3 years) men matched for physical characteristics with low (Low-fit; 39.8 ± 2.5 ml O 2  kg -1  min -1 ), moderate (Mod-fit; 50.9 ± 1.2 ml O 2  kg -1  min -1 ) and high aerobic fitness (High-fit; 62.0 ± 4.4 ml O 2  kg -1  min -1 ; each n = 8), during three 30 min bouts of cycling in dry heat (40°C, 12% relative humidity) at increasing rates of metabolic heat production of 300 (Ex1), 400 (Ex2) and 500 W (Ex3), each followed by a 15 min recovery period. Each group was exposed to a similar net heat load (metabolic plus ∼100 W dry heat gain; P = 0.83) during each exercise bout [∼400 (Ex1), ∼500 (Ex2) and ∼600 W (Ex3); P < 0.01]. Although evaporative heat loss was similar between groups during Ex1 (P = 0.33), evaporative heat loss was greater in the High-fit (Ex2, 466 ± 21 W; Ex3, 557 ± 26 W) compared with the Low-fit group (Ex2, 439 ± 22 W; Ex3, 511 ± 20�

Dual Rate Adaptive Control for an Industrial Heat Supply Process Using Signal Compensation Approach

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

Chai, Tianyou; Jia, Yao; Wang, Hong

The industrial heat supply process (HSP) is a highly nonlinear cascaded process which uses a steam valve opening as its control input, the steam flow-rate as its inner loop output and the supply water temperature as its outer loop output. The relationship between the heat exchange rate and the model parameters, such as steam density, entropy, and fouling correction factor and heat exchange efficiency are unknown and nonlinear. Moreover, these model parameters vary in line with steam pressure, ambient temperature and the residuals caused by the quality variations of the circulation water. When the steam pressure and the ambient temperaturemore » are of high values and are subjected to frequent external random disturbances, the supply water temperature and the steam flow-rate would interact with each other and fluctuate a lot. This is also true when the process exhibits unknown characteristic variations of the process dynamics caused by the unexpected changes of the heat exchange residuals. As a result, it is difficult to control the supply water temperature and the rates of changes of steam flow-rate well inside their targeted ranges. In this paper, a novel compensation signal based dual rate adaptive controller is developed by representing the unknown variations of dynamics as unmodeled dynamics. In the proposed controller design, such a compensation signal is constructed and added onto the control signal obtained from the linear deterministic model based feedback control design. Such a compensation signal aims at eliminating the unmodeled dynamics and the rate of changes of the currently sample unmodeled dynamics. A successful industrial application is carried out, where it has been shown that both the supply water temperature and the rate of the changes of the steam flow-rate can be controlled well inside their targeted ranges when the process is subjected to unknown variations of its dynamics.« less

Investigation of the feasibility of elective irradiation to neck level Ib using intensity-modulated radiotherapy for patients with nasopharyngeal carcinoma: a retrospective analysis.

PubMed

Zhang, Fan; Cheng, Yi-Kan; Li, Wen-Fei; Guo, Rui; Chen, Lei; Sun, Ying; Mao, Yan-Ping; Zhou, Guan-Qun; Liu, Xu; Liu, Li-Zhi; Lin, Ai-Hua; Tang, Ling-Long; Ma, Jun

2015-10-15

To assess the feasibility of elective neck irradiation to level Ib in nasopharyngeal carcinoma (NPC) using intensity-modulated radiation therapy (IMRT). We retrospectively analyzed 1438 patients with newly-diagnosed, non-metastatic and biopsy-proven NPC treated with IMRT. Greatest dimension of level IIa LNs (DLN-IIa) ≥ 20 mm and/or level IIa LNs with extracapsular spread (ES), oropharynx involvement and positive bilateral cervical lymph nodes (CLNs) were independently significantly associated with metastasis to level Ib LN at diagnosis. No recurrence at level Ib was observed in the 904 patients without these characteristics (median follow-up, 38.7 months; range, 1.3-57.8 months), these patients were classified as low risk. Level Ib irradiation was not an independent risk factor for locoregional failure-free survival, distant failure-free survival, failure-free survival or overall survival in low risk patients. The frequency of grade ≥ 2 subjective xerostomia at 12 months after radiotherapy was not significantly different between low risk patients who received level Ib-sparing, unilateral level Ib-covering or bilateral level Ib-covering IMRT. Level Ib-sparing IMRT should be safe and feasible for patients without a DLN-IIa ≥ 20 mm and/or level IIa LNs with ES, positive bilateral CLNs or oropharynx involvement at diagnosis. Further investigations based on specific criteria for dose constraints for the submandibular glands are warranted to confirm the benefit of elective level Ib irradiation.

Flash-Fire Propensity and Heat-Release Rate Studies of Improved Fire Resistant Materials

NASA Technical Reports Server (NTRS)

Fewell, L. L.

1978-01-01

Twenty-six improved fire resistant materials were tested for flash-fire propensity and heat release rate properties. The tests were conducted to obtain a descriptive index based on the production of ignitable gases during the thermal degradation process and on the response of the materials under a specific heat load.

A Measure of Suffering in relation to Anxiety and Quality of Life in IBS Patients: Preliminary Results.

PubMed

Pletikosić Tončić, Sanda; Tkalčić, Mladenka

2017-01-01

Irritable bowel syndrome (IBS) is a chronic gastrointestinal (GI) disorder with a severe impact on quality of life (QoL). We explored the relationship of a visual measure of suffering, the PRISM-RII, with quality of life (QoL) and anxiety measures in IBS patients. Participants were 44 IBS patients who completed several questionnaires and kept a symptom diary for two weeks. The measures used were PRISM-RII (self-illness separation (SIS); illness perception measure (IPM)); IBS-36 (IBS health related QoL); SF-36 (physical and mental health related QoL); State-Trait Anxiety Inventory (STAI-T); Visceral Sensitivity Index (VSI; GI-specific anxiety); and a symptom diary. SIS was negatively correlated to VSI, while IPM was negatively correlated to SIS and the physical component of SF-36 and positively to VSI and symptom severity. We found significant differences between participants who perceive their illness as small and those who perceive it as medium in SIS, symptom severity, VSI, and the mental component of SF-36. Participants, who perceived their illness as small, represented their illness as more distant, showed lower average symptom severity, and had lower GI-specific anxiety and higher QoL. The results indicate that IPM and SIS can be useful in discriminating patients with more prominent psychological difficulties and QoL impairment.

A real-time heat strain risk classifier using heart rate and skin temperature.

PubMed

Buller, Mark J; Latzka, William A; Yokota, Miyo; Tharion, William J; Moran, Daniel S

2008-12-01

Heat injury is a real concern to workers engaged in physically demanding tasks in high heat strain environments. Several real-time physiological monitoring systems exist that can provide indices of heat strain, e.g. physiological strain index (PSI), and provide alerts to medical personnel. However, these systems depend on core temperature measurement using expensive, ingestible thermometer pills. Seeking a better solution, we suggest the use of a model which can identify the probability that individuals are 'at risk' from heat injury using non-invasive measures. The intent is for the system to identify individuals who need monitoring more closely or who should apply heat strain mitigation strategies. We generated a model that can identify 'at risk' (PSI 7.5) workers from measures of heart rate and chest skin temperature. The model was built using data from six previously published exercise studies in which some subjects wore chemical protective equipment. The model has an overall classification error rate of 10% with one false negative error (2.7%), and outperforms an earlier model and a least squares regression model with classification errors of 21% and 14%, respectively. Additionally, the model allows the classification criteria to be adjusted based on the task and acceptable level of risk. We conclude that the model could be a valuable part of a multi-faceted heat strain management system.

IBS and possible luminosity improvement for RHIC operation below transition energy

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

Fedotov,A.V.

There is a strong interest in low-energy RHIC collisions in the energy range below present RHIC transition energy. These collisions win help to answer one of the key questions in the field of QCD about the existence and location of a critical point on the QCD phase diagram. For such low-energy RHIC operation, particle losses from the RF bucket are of particular concern since the longitudinal beam size is comparable to the existing RF bucket at low energies. In this paper, we explore an Intrabeam Scattering (IBS) feature below transition energy that drives the transverse and longitudinal beam temperatures towardsmore » equilibrium to see whether we can minimize longitudinal diffusion due to IBS and predict some luminosity improvement for the low-energy RHIC project.« less

Effective factor of virtual team: Resolving communication breakdown in IBS construction project

NASA Astrophysics Data System (ADS)

Pozin, Mohd Affendi Ahmad; Nawi, Mohd. Nasrun Mohd.

2016-08-01

Currently, rapid development of information technology has provided new opportunities to organisation toward increasing the effectiveness of collaboration and teamwork management. Thus the virtual team approach has been implemented in numerous of field. However, there is limited study of virtual team in construction project management. Currently IBS project is still based on traditional construction process which is isolation team working environment. Therefore this approach has been declared as a main barrier to ensure cooperative working relation in term of communication and information in between project stakeholders. Thus, this paper through literature review is attempted to present a discussion of the virtual team approach toward IBS project in developing effective team communication during construction project.

Heat Shock Response in Yeast Involves Changes in Both Transcription Rates and mRNA Stabilities

PubMed Central

Castells-Roca, Laia; García-Martínez, José; Moreno, Joaquín; Herrero, Enrique; Bellí, Gemma; Pérez-Ortín, José E.

2011-01-01

We have analyzed the heat stress response in the yeast Saccharomyces cerevisiae by determining mRNA levels and transcription rates for the whole transcriptome after a shift from 25°C to 37°C. Using an established mathematical algorithm, theoretical mRNA decay rates have also been calculated from the experimental data. We have verified the mathematical predictions for selected genes by determining their mRNA decay rates at different times during heat stress response using the regulatable tetO promoter. This study indicates that the yeast response to heat shock is not only due to changes in transcription rates, but also to changes in the mRNA stabilities. mRNA stability is affected in 62% of the yeast genes and it is particularly important in shaping the mRNA profile of the genes belonging to the environmental stress response. In most cases, changes in transcription rates and mRNA stabilities are homodirectional for both parameters, although some interesting cases of antagonist behavior are found. The statistical analysis of gene targets and sequence motifs within the clusters of genes with similar behaviors shows that both transcriptional and post-transcriptional regulons apparently contribute to the general heat stress response by means of transcriptional factors and RNA binding proteins. PMID:21364882

Heart rate variability during exertional heat stress: effects of heat production and treatment.

PubMed

Flouris, Andreas D; Bravi, Andrea; Wright-Beatty, Heather E; Green, Geoffrey; Seely, Andrew J; Kenny, Glen P

2014-04-01

We assessed the efficacy of different treatments (i.e., treatment with ice water immersion vs. natural recovery) and the effect of exercise intensities (i.e., low vs. high) for restoring heart rate variability (HRV) indices during recovery from exertional heat stress (EHS). Nine healthy adults (26 ± 3 years, 174.2 ± 3.8 cm, 74.6 ± 4.3 kg, 17.9 ± 2.8 % body fat, 57 ± 2 mL·kg·(-1) min(-1) peak oxygen uptake) completed four EHS sessions incorporating either walking (4.0-4.5 km·h(-1), 2 % incline) or jogging (~7.0 km·h(-1), 2 % incline) on a treadmill in a hot-dry environment (40 °C, 20-30 % relative humidity) while wearing a non-permeable rain poncho for a slow or fast rate of rectal temperature (T re) increase, respectively. Upon reaching a T re of 39.5 °C, participants recovered until T re returned to 38 °C either passively or with whole-body immersion in 2 °C water. A comprehensive panel of 93 HRV measures were computed from the time, frequency, time-frequency, scale-invariant, entropy and non-linear domains. Exertional heat stress significantly affected 60/93 HRV measures analysed. Analyses during recovery demonstrated that there were no significant differences between HRV measures that had been influenced by EHS at the end of passive recovery vs. whole-body cooling treatment (p > 0.05). Nevertheless, the cooling treatment required statistically significantly less time to reduce T re (p < 0.001). While EHS has a marked effect on autonomic nervous system modulation and whole-body immersion in 2 °C water results in faster cooling, there were no observed differences in restoration of autonomic heart rate modulation as measured by HRV indices with whole-body cold-water immersion compared to passive recovery in thermoneutral conditions.

Virtual Screening for the Development of Dual-Inhibitors Targeting Topoisomerase IB and Tyrosyl-DNA Phosphodiesterase 1.

PubMed

Cardamone, Francesca; Pizzi, Simone; Iacovelli, Federico; Falconi, Mattia; Desideri, Alessandro

2017-01-01

Human topoisomerase IB is an important target in cancer therapy and drugs selectively stabilizing the topoisomerase IB-DNA covalent complex are in clinical use for several cancer types. Tyrosyl- DNA phosphodiesterase 1 is involved in the DNA repair resolving the topoisomerase IB-DNA covalent complex that is extremely dangerous for the survival of the cells since it produces an irreversible DNA damage. Given the close biological relationship between these two enzymes, the development of synergistic inhibitors, called dual-inhibitors, is an important challenge in cancer therapy and computer-aided drug design may help in the identification of the best compounds. In this review, an overview of the compounds inhibiting one of the two enzymes or acting as dual inhibitors is provided. Moreover, the general procedures of the virtual screening approach, providing a description of two widely used opensource programs, namely AutoDock4 and AutoDock Vina, are described. Finally, an application of the two programs on a selected number of dual inhibitors for tyrosyl-DNA phosphodiesterase 1 and topoisomerase IB and their performance is briefly discussed. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Constraints on Lunar Heat Flow Rates from Diviner Lunar Radiometer Polar Observations

NASA Astrophysics Data System (ADS)

Paige, D. A.; Siegler, M. A.; Vasavada, A. R.

2010-12-01

The heat flow rate from the lunar interior is a fundamental property of the moon that is related to its composition, interior structure and history. Lunar heat flow rates have been measured at the Apollo 15 and 17 landing sites [1], but it is widely believed that the measured values of 0.021 Wm-2 and 0.016 Wm-2 respectively may not be representative of the moon as a whole due to the presence of enhanced radiogenic elements at these landing sites [2]. The Diviner Lunar Radiometer Experiment on the Lunar Reconnaissance Orbiter [3] has acquired an extensive set of thermal emission from the lunar surface at infrared wavelengths, including the first radiometric measurements of surface temperatures at the lunar poles [4]. Due to its low obliquity and rough topography, the moon has extensive cryogenic regions at high latitudes that never receive direct sunlight. The temperatures of the coldest of these regions can be used to place upper limits on the heat flow rate from the lunar interior because if other heat sources are neglected, then surface thermal emission is balanced by heat flow from warmer lunar interior [5]. Diviner has mapped the north and south polar regions over a complete annual cycle and we have identified a 4 km2 area within Hermite Crater in the north polar region that has a winter season nighttime Channel 9 (100-400 micron) brightness temperatures in of less than 20K. These low temperatures would imply a lunar heat flow rate of less than 0.010 Wm-2, which may be consistent with expectations for regions of the moon that do not contain enhanced concentrations of radiogenic elements [2,6], as is the case for the north polar region of the moon [7]. [1] Langseth, M. G. et al, Proc. Lunar Sci. Conf, 7th, 3143-3171, 1976. [2] Warren, P. H. and K. K. L. Rasmussen, JGR 92, 3453-3465, 1987. [3] Paige, D. A. et al, Space Sci. Rev, 150:125-160, 2010. [4] Paige, D. A. et al., Science, in press, 2010. [5] Watson, K. JGR 72, 3301-3302, 1967. [6] Wieczorek, M. A. and R

A Novel RNA Polymerase I Transcription Initiation Factor, TIF-IE, Commits rRNA Genes by Interaction with TIF-IB, Not by DNA Binding

PubMed Central

Al-Khouri, Anna Maria; Paule, Marvin R.

2002-01-01

In the small, free-living amoeba Acanthamoeba castellanii, rRNA transcription requires, in addition to RNA polymerase I, a single DNA-binding factor, transcription initiation factor IB (TIF-IB). TIF-IB is a multimeric protein that contains TATA-binding protein (TBP) and four TBP-associated factors that are specific for polymerase I transcription. TIF-IB is required for accurate and promoter-specific initiation of rRNA transcription, recruiting and positioning the polymerase on the start site by protein-protein interaction. In A. castellanii, partially purified TIF-IB can form a persistent complex with the ribosomal DNA (rDNA) promoter while homogeneous TIF-IB cannot. An additional factor, TIF-IE, is required along with homogeneous TIF-IB for the formation of a stable complex on the rDNA core promoter. We show that TIF-IE by itself, however, does not bind to the rDNA promoter and thus differs in its mechanism from the upstream binding factor and upstream activating factor, which carry out similar complex-stabilizing functions in vertebrates and yeast, respectively. In addition to its presence in impure TIF-IB, TIF-IE is found in highly purified fractions of polymerase I, with which it associates. Renaturation of polypeptides excised from sodium dodecyl sulfate-polyacrylamide gels showed that a 141-kDa polypeptide possesses all the known activities of TIF-IE. PMID:11784852

A novel RNA polymerase I transcription initiation factor, TIF-IE, commits rRNA genes by interaction with TIF-IB, not by DNA binding.

PubMed

Al-Khouri, Anna Maria; Paule, Marvin R

2002-02-01

In the small, free-living amoeba Acanthamoeba castellanii, rRNA transcription requires, in addition to RNA polymerase I, a single DNA-binding factor, transcription initiation factor IB (TIF-IB). TIF-IB is a multimeric protein that contains TATA-binding protein (TBP) and four TBP-associated factors that are specific for polymerase I transcription. TIF-IB is required for accurate and promoter-specific initiation of rRNA transcription, recruiting and positioning the polymerase on the start site by protein-protein interaction. In A. castellanii, partially purified TIF-IB can form a persistent complex with the ribosomal DNA (rDNA) promoter while homogeneous TIF-IB cannot. An additional factor, TIF-IE, is required along with homogeneous TIF-IB for the formation of a stable complex on the rDNA core promoter. We show that TIF-IE by itself, however, does not bind to the rDNA promoter and thus differs in its mechanism from the upstream binding factor and upstream activating factor, which carry out similar complex-stabilizing functions in vertebrates and yeast, respectively. In addition to its presence in impure TIF-IB, TIF-IE is found in highly purified fractions of polymerase I, with which it associates. Renaturation of polypeptides excised from sodium dodecyl sulfate-polyacrylamide gels showed that a 141-kDa polypeptide possesses all the known activities of TIF-IE.

Effect of radiator position and mass flux on the dryer room heat transfer rate

NASA Astrophysics Data System (ADS)

Mirmanto, M.; Sulistyowati, E. D.; Okariawan, I. D. K.

A room radiator as usually used in cold countries, is actually able to be used as a heat source to dry goods, especially in the rainy season where the sun seldom shines due to much rain and cloud. Experiments to investigate effects of radiator position and mass flux on heat transfer rate were performed. This study is to determine the best position of the radiator and the optimum mass flux. The radiator used was a finned radiator made of copper pipes and aluminum fins with an overall dimension of 220 mm × 50 mm × 310 mm. The prototype room was constructed using plywood and wood frame with an overall size of 1000 mm × 1000 mm × 1000 mm. The working fluid was heated water flowing inside the radiator and air circulating naturally inside the prototype room. The nominal mass fluxes employed were 800, 900 and 1000 kg/m2 s. The water was kept at 80 °C at the radiator entrance, while the initial air temperature inside the prototype room was 30 °C. Three positions of the radiator were examined. The results show that the effect of the mass flux on the forced and free convection heat transfer rate is insignificant but the radiator position strongly affects the heat transfer rate for both forced and free convection.

Effect of temperature and heating rate on apparent lethal concentrations of pyrolysis products

NASA Technical Reports Server (NTRS)

Hilado, C. J.; Solis, A. N.; Marcussen, W. H.; Furst, A.

1976-01-01

The apparent lethal concentrations for 50 percent of the test animals of the pyrolysis products from twelve polymeric materials were studied as a function of temperature and heating rate. The materials were polyethylene, nylon 6, ABS, polycarbonate, polyether sulfone, polyaryl sulfone, wool fabric, aromatic polyamide fabric, polychloroprene foam, polyvinyl fluoride film, Douglas fir, and red oak. The apparent lethal concentration values of most materials vary significantly with temperature and heating rate. The apparent lethal concentration values, based on weight of sample charged, appears to effectively integrate the thermophysical, thermochemical, and physiological responses from a known quantity of material under specified imposed conditions.

A study on alkaline heat treated Mg-Ca alloy for the control of the biocorrosion rate.

PubMed

Gu, X N; Zheng, W; Cheng, Y; Zheng, Y F

2009-09-01

To reduce the biocorrosion rate by surface modification, Mg-Ca alloy (1.4wt.% Ca content) was soaked in three alkaline solutions (Na(2)HPO(4), Na(2)CO(3) and NaHCO(3)) for 24h, respectively, and subsequently heat treated at 773K for 12h. Scanning electron microscopy and energy-dispersive spectroscopy results revealed that magnesium oxide layers with the thickness of about 13, 9 and 26microm were formed on the surfaces of Mg-Ca alloy after the above different alkaline heat treatments. Atomic force microscopy showed that the surfaces of Mg-Ca alloy samples became rough after three alkaline heat treatments. The in vitro corrosion tests in simulated body fluid indicated that the corrosion rates of Mg-Ca alloy were effectively decreased after alkaline heat treatments, with the following sequence: NaHCO(3) heatedheatedheated. The cytotoxicity evaluation revealed that none of the alkaline heat treated Mg-Ca alloy samples induced toxicity to L-929 cells during 7days culture.

Effects of whole body heating on dynamic baroreflex regulation of heart rate in humans

NASA Technical Reports Server (NTRS)

Crandall, C. G.; Zhang, R.; Levine, B. D.

2000-01-01

The purpose of this project was to identify whether dynamic baroreflex regulation of heart rate (HR) is altered during whole body heating. In 14 subjects, dynamic baroreflex regulation of HR was assessed using transfer function analysis. In normothermic and heat-stressed conditions, each subject breathed at a fixed rate (0. 25 Hz) while beat-by-beat HR and systolic blood pressure (SBP) were obtained. Whole body heating significantly increased sublingual temperature, HR, and forearm skin blood flow. Spectral analysis of HR and SBP revealed that the heat stress significantly reduced HR and SBP variability within the high-frequency range (0.2-0.3 Hz), reduced SBP variability within the low-frequency range (0.03-0.15 Hz), and increased the ratio of low- to high-frequency HR variability (all P < 0.01). Transfer function gain analysis showed that the heat stress reduced dynamic baroreflex regulation of HR within the high-frequency range (from 1.04 +/- 0.06 to 0.54 +/- 0.6 beats. min(-1). mmHg(-1); P < 0.001) without significantly affecting the gain in the low-frequency range (P = 0.63). These data suggest that whole body heating reduced high-frequency dynamic baroreflex regulation of HR associated with spontaneous changes in blood pressure. Reduced vagal baroreflex regulation of HR may contribute to reduced orthostatic tolerance known to occur in humans during heat stress.

Influence of Strain Rate on Heat Release under Quasi-Static Stretching of Metals. Experiment

NASA Astrophysics Data System (ADS)

Zimin, B. A.; Sventitskaya, V. E.; Smirnov, I. V.; Sud'enkov, Yu. V.

2018-04-01

The paper presents the results of experimental studies of energy dissipation during a quasi-static stretching of metals and alloys at room temperature. The strain rates varied in the range of 10-3-10-2 s-1. Samples of M1 copper, AZ31B magnesium alloy, BT6 titanium, 12Cr18Ni10Ti steel, and D16AM aluminum alloy were analyzed. The experimental results demonstrated a significant dependence of the heat release on the strain rate in the absence of its influence on stress-strain diagrams for all the metals studied in this range of strain rates. The correlation of the changes in the character of heat release with the processes of structural transformations at various stages of plastic flow is shown on the qualitative level. A difference in the nature of the processes of heat release in materials with different ratios of the plasticity and strength is noted.

Optimization of pelvic heating rate distributions with electromagnetic phased arrays.

PubMed

Paulsen, K D; Geimer, S; Tang, J; Boyse, W E

1999-01-01

Deep heating of pelvic tumours with electromagnetic phased arrays has recently been reported to improve local tumour control when combined with radiotherapy in a randomized clinical trial despite the fact that rather modest elevations in tumour temperatures were achieved. It is reasonable to surmise that improvements in temperature elevation could lead to even better tumour response rates, motivating studies which attempt to explore the parameter space associated with heating rate delivery in the pelvis. Computational models which are based on detailed three-dimensional patient anatomy are readily available and lend themselves to this type of investigation. In this paper, volume average SAR is optimized in a predefined target volume subject to a maximum allowable volume average SAR outside this zone. Variables under study include the position of the target zone, the number and distribution of radiators and the applicator operating frequency. The results show a clear preference for increasing frequency beyond 100 MHz, which is typically applied clinically, especially as the number of antennae increases. Increasing both the number of antennae per circumferential distance around the patient, as well as the number of independently functioning antenna bands along the patient length, is important in this regard, although improvements were found to be more significant with increasing circumferential antenna density. However, there is considerable site specific variation and cases occur where lower numbers of antennae spread out over multiple longitudinal bands are more advantageous. The results presented here have been normalized relative to an optimized set of antenna array amplitudes and phases operating at 100 MHz which is a common clinical configuration. The intent is to provide some indications of avenues for improving the heating rate distributions achievable with current technology.

Extension of the master sintering curve for constant heating rate modeling

NASA Astrophysics Data System (ADS)

McCoy, Tammy Michelle

The purpose of this work is to extend the functionality of the Master Sintering Curve (MSC) such that it can be used as a practical tool for predicting sintering schemes that combine both a constant heating rate and an isothermal hold. Rather than just being able to predict a final density for the object of interest, the extension to the MSC will actually be able to model a sintering run from start to finish. Because the Johnson model does not incorporate this capability, the work presented is an extension of what has already been shown in literature to be a valuable resource in many sintering situations. A predicted sintering curve that incorporates a combination of constant heating rate and an isothermal hold is more indicative of what is found in real-life sintering operations. This research offers the possibility of predicting the sintering schedule for a material, thereby having advanced information about the extent of sintering, the time schedule for sintering, and the sintering temperature with a high degree of accuracy and repeatability. The research conducted in this thesis focuses on the development of a working model for predicting the sintering schedules of several stabilized zirconia powders having the compositions YSZ (HSY8), 10Sc1CeSZ, 10Sc1YSZ, and 11ScSZ1A. The compositions of the four powders are first verified using x-ray diffraction (XRD) and the particle size and surface area are verified using a particle size analyzer and BET analysis, respectively. The sintering studies were conducted on powder compacts using a double pushrod dilatometer. Density measurements are obtained both geometrically and using the Archimedes method. Each of the four powders is pressed into ¼" diameter pellets using a manual press with no additives, such as a binder or lubricant. Using a double push-rod dilatometer, shrinkage data for the pellets is obtained over several different heating rates. The shrinkage data is then converted to reflect the change in relative

Design and simulation of heat exchangers using Aspen HYSYS, and Aspen exchanger design and rating for paddy drying application

NASA Astrophysics Data System (ADS)

Janaun, J.; Kamin, N. H.; Wong, K. H.; Tham, H. J.; Kong, V. V.; Farajpourlar, M.

2016-06-01

Air heating unit is one of the most important parts in paddy drying to ensure the efficiency of a drying process. In addition, an optimized air heating unit does not only promise a good paddy quality, but also save more for the operating cost. This study determined the suitable and best specifications heating unit to heat air for paddy drying in the LAMB dryer. In this study, Aspen HYSYS v7.3 was used to obtain the minimum flow rate of hot water needed. The resulting data obtained from Aspen HYSYS v7.3 were used in Aspen Exchanger Design and Rating (EDR) to generate heat exchanger design and costs. The designs include shell and tubes and plate heat exchanger. The heat exchanger was designed in order to produce various drying temperatures of 40, 50, 60 and 70°C of air with different flow rate, 300, 2500 and 5000 LPM. The optimum condition for the heat exchanger were found to be plate heat exchanger with 0.6 mm plate thickness, 198.75 mm plate width, 554.8 mm plate length and 11 numbers of plates operating at 5000 LPM air flow rate.

Effects of slip, slip rate, and shear heating on the friction of granite

USGS Publications Warehouse

Blanpied, M.L.; Tullis, T.E.; Weeks, J.D.

1998-01-01

The stability of fault slip is sensitive to the way in which frictional strength responds to changes in slip rate and in particular to the effective velocity dependence of steady state friction ????ss/?? ln V. This quantity can vary substantially with displacement, temperature and slip rate. To investigate the physical basis for this behavior and the possible influence of shear heating, we slid initially bare granite surfaces in unconfined rotary shear to displacements of hundreds of millimeters at normal stresses, ??n, of 10 and 25 MPa and at room temperature. We imposed step changes in slip rate within the range 10-2 to 103.5 ??m/s and also monitored frictional heating with thermistors embedded in the granite. The transient response of ?? to slip rate steps was fit to a rate- and state-dependent friction law using two state variables to estimate the values of several parameters in the constitutive law. The first 20 mm of slip shows rising friction and falling ????ss/?? ln V; further slip shows roughly constant friction, ????ss/?? ln V and parameter values, suggesting that a steady state condition is reached on the fault surface. At V ??? 10 ??m/s, ????ss/?? ln V = -0.004 ?? 0.001. At higher rates the response is sensitive to normal stress: At ??n = 25 MPa granite shows a transition to effective velocity strengthening (????ss/?? ln V = 0.008 ?? 0.004) at the highest slip rates tested. At 10 MPa granite shows a less dramatic change to ????ss/?? ln V ??? 0 at the highest rates. The maximum temperature measured in the granite is ???60??C at 25 MPa and 103.5 ??m/s. Temperatures are in general agreement with a numerical model of heat conduction which assumes spatially homogeneous frictional heating over the sliding surface. The simplest interpretation of our measurements of ????ss/?? ln V is that the granite is inherently veocity weakening (?????ss/??? In V 0 mimics velocity strengthening. These results have implications for the frictional behavior of faults during

Internal stress-induced melting below melting temperature at high-rate laser heating

NASA Astrophysics Data System (ADS)

Hwang, Yong Seok; Levitas, Valery I.

2014-06-01

In this Letter, continuum thermodynamic and phase field approaches (PFAs) predicted internal stress-induced reduction in melting temperature for laser-irradiated heating of a nanolayer. Internal stresses appear due to thermal strain under constrained conditions and completely relax during melting, producing an additional thermodynamic driving force for melting. Thermodynamic melting temperature for Al reduces from 933.67 K for a stress-free condition down to 898.1 K for uniaxial strain and to 920.8 K for plane strain. Our PFA simulations demonstrated barrierless surface-induced melt nucleation below these temperatures and propagation of two solid-melt interfaces toward each other at the temperatures very close to the corresponding predicted thermodynamic equilibrium temperatures for the heating rate Q ≤1.51×1010K/s. At higher heating rates, kinetic superheating competes with a reduction in melting temperature and melting under uniaxial strain occurs at 902.1 K for Q = 1.51 × 1011 K/s and 936.9 K for Q = 1.46 × 1012 K/s.

Investigating the oxidation mechanism of tantalum nanoparticles at high heating rates

NASA Astrophysics Data System (ADS)

DeLisio, Jeffery B.; Wang, Xizheng; Wu, Tao; Egan, Garth C.; Jacob, Rohit J.; Zachariah, Michael R.

2017-12-01

Reduced diffusion length scales and increased specific surface areas of nanosized metal fuels have recently demonstrated increased reaction rates for these systems, increasing their relevance in a wide variety of applications. The most commonly employed metal fuel, aluminum, tends to oxidize rapidly near its melting point (660 °C) in addition to undergoing a phase change of the nascent oxide shell. To further expand on the understanding of nanosized metal fuel oxidation, tantalum nanoparticles were studied due to their high melting point (3017 °C) in comparison to aluminum. Both traditional slow heating rate and in-situ high heating rate techniques were used to probe the oxidation of tantalum nanoparticles in oxygen containing environments in addition to nanothermite mixtures. When oxidized by gas phase oxygen, the oxide shell of the tantalum nanoparticles rapidly crystallized creating cracks that may attribute to enhanced oxygen diffusion into the particle. In the case of tantalum based nanothermites, oxide shell crystallization was shown to induce reactive sintering with the metal oxide resulting in a narrow range of ignition temperatures independent of the metal oxide used. The oxidation mechanism was modeled using the Deal-Grove model to extract rate parameters, and theoretical burn times for tantalum based nanocomposites were calculated.

Molecular dynamics study on the effect of boundary heating rate on the phase change characteristics of thin film liquid

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

Hasan, Mohammad Nasim, E-mail: nasim@me.buet.ac.bd.com; Morshed, A. K. M. Monjur, E-mail: shavik@me.buet.ac.bd.com; Rabbi, Kazi Fazle, E-mail: rabbi35.me10@gmail.com

2016-07-12

In this study, theoretical investigation of thin film liquid phase change phenomena under different boundary heating rates has been conducted with the help of molecular dynamics simulation. To do this, the case of argon boiling over a platinum surface has been considered. The study has been conducted to get a better understanding of the nano-scale physics of evaporation/boiling for a three phase system with particular emphasis on the effect of boundary heating rate. The simulation domain consisted of liquid and vapor argon atoms placed over a platinum wall. Initially the whole system was brought to an equilibrium state at 90more » K with the help of equilibrium molecular dynamics and then the temperature of the bottom wall was increased to a higher temperature (250 K/130 K) over a finite heating period. Depending on the heating period, the boundary heating rate has been varied in the range of 1600×10{sup 9} K/s to 8×10{sup 9} K/s. The variations of argon region temperature, pressure, net evaporation number with respect to time under different boundary heating rates have been determined and discussed. The heat fluxes normal to platinum wall for different cases were also calculated and compared with theoretical upper limit of maximum possible heat transfer to elucidate the effect of boundary heating rate.« less

Aerodynamic heating rate distributions induced by trailing edge controls on hypersonic aircraft configurations at Mach 8

NASA Technical Reports Server (NTRS)

Kaufman, L. G., II; Johnson, C. B.

1984-01-01

Aerodynamic surface heating rate distributions in three dimensional shock wave boundary layer interaction flow regions are presented for a generic set of model configurations representative of the aft portion of hypersonic aircraft. Heat transfer data were obtained using the phase change coating technique (paint) and, at particular spanwise and streamwise stations for sample cases, by the thin wall transient temperature technique (thermocouples). Surface oil flow patterns are also shown. The good accuracy of the detailed heat transfer data, as attested in part by their repeatability, is attributable partially to the comparatively high temperature potential of the NASA-Langley Mach 8 Variable Density Tunnel. The data are well suited to help guide heating analyses of Mach 8 aircraft, and should be considered in formulating improvements to empiric analytic methods for calculating heat transfer rate coefficient distributions.

Descending pain modulation in irritable bowel syndrome (IBS): a systematic review and meta-analysis.

PubMed

Chakiath, Rosemary J; Siddall, Philip J; Kellow, John E; Hush, Julia M; Jones, Mike P; Marcuzzi, Anna; Wrigley, Paul J

2015-12-10

Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder. While abdominal pain is a dominant symptom of IBS, many sufferers also report widespread hypersensitivity and present with other chronic pain conditions. The presence of widespread hypersensitivity and extra-intestinal pain conditions suggests central nervous dysfunction. While central nervous system dysfunction may involve the spinal cord (central sensitisation) and brain, this review will focus on one brain mechanism, descending pain modulation. We will conduct a comprehensive search for the articles indexed in the databases Ovid MEDLINE, Ovid Embase, Ovid PsycINFO and Cochrane Central Register of Controlled Trial (CENTRAL) from their inception to August 2015, that report on any aspect of descending pain modulation in irritable bowel syndrome. Two independent reviewers will screen studies for eligibility, assess risk of bias and extract relevant data. Results will be tabulated and, if possible, a meta-analysis will be carried out. The systematic review outlined in this protocol aims to summarise current knowledge regarding descending pain modulation in IBS. PROSPERO CRD42015024284.

New therapeutic options for IBS: the role of the first in class mixed µ- opioid receptor agonist and δ-opioid receptor antagonist (mudelta) eluxadoline.

PubMed

Corsetti, Maura; Whorwell, Peter

2017-04-01

Irritable bowel syndrome (IBS) is a prevalent functional gastrointestinal disorder which represents a major cost to healthcare services. IBS-D patients represent about one-third of the IBS population and are currently treated with antispasmodics, loperamide, bile acid sequestrants and antidepressants. Alosetron and rifaximin are also available in USA, ramosetron in Japan, Korea and Thailand and ondansetron as an off-label treatment. Areas covered: This article focuses on eluxadoline, a novel pharmacological agent that has recently been approved by both the FDA and EMA for treatment of patients with IBS-D. Expert commentary: The efficacy and safety of eluxadoline in treating bowel habit alterations and pain, both in the short and long-term, make the drug a welcome addition to our therapeutic alternatives in IBS-D. Its positioning in any IBS algorithm will depend on the 'real world' prevalence of the small risk of sphincter of Oddi spasm and mild pancreatitis.

Space Shuttle Solid Rocket Motor Plume Pressure and Heat Rate Measurements

NASA Technical Reports Server (NTRS)

vonEckroth, Wulf; Struchen, Leah; Trovillion, Tom; Perez, Ravael; Nereolich, Shaun; Parlier, Chris

2012-01-01

The Solid Rocket Booster (SRB) Main Flame Deflector (MFD) at Launch Complex 39A was instrumented with sensors to measure heat rates, pressures, and temperatures on the last three Space Shuttle launches. Because the SRB plume is hot and erosive, a robust Tungsten Piston Calorimeter was developed to compliment the measurements made by off-the-shelf sensors. Witness materials were installed and their melting and erosion response to the Mach 2 / 4500 F / 4-second duration plume was observed. The data show that the specification document used for the design of the MFD thermal protection system over-predicted heat rates by a factor of 3 and under-predicted pressures by a factor of 2. These findings will be used to baseline NASA Computational Fluid Dynamics models and develop innovative MFD designs for the Space Launch System (SLS) before this vehicle becomes operational in 2017.

A review on the current issues and barriers of Industrialised Building System (IBS) adoption in Malaysia’s construction industry

NASA Astrophysics Data System (ADS)

Amin, M. A. Mohd; Abas, N. H.; Shahidan, S.; Rahmat, M. H.; Suhaini, N. A.; Nagapan, S.; Rahim, R. Abdul

2017-11-01

Malaysia considers the construction industry as one of the main contributors to its Gross Domestic Product (GDP). However, there are some unresolved issues arising from the ongoing and widespread adoption of the conventional method of construction such as the resultant fragmentation of the industry itself; delays in production and delivery time of unnecessary wastages and lack of sustainability practice. Malaysian Government has been continuously encouraging the industry to use, partly or if not wholly, the Industrialized Building System (IBS), which is considered to be an important part of sustainable construction initiative. IBS was introduced to Malaysia as the solution to issues related to dependencies of foreign workers, raising demand for affordable accommodations and improving image, quality and productivity of construction industry. However, the IBS adoption in Malaysia remains low. This paper presents the review of the current issues and barriers of IBS adoption in Malaysian construction industry.

Glucose-6-phosphate transporter gene therapy corrects metabolic and myeloid abnormalities in glycogen storage disease type Ib mice

PubMed Central

Yiu, Wai Han; Pan, Chi-Jiunn; Allamarvdasht, Mohammad; Kim, So Youn; Chou, Janice Y.

2008-01-01

Glycogen storage disease type Ib (GSD-Ib) is caused by a deficiency in the glucose-6-phosphate transporter (G6PT), an endoplasmic reticulum-associated transmembrane protein that is ubiquitously expressed. GSD-Ib patients suffer from disturbed glucose homeostasis and myeloid dysfunctions. To evaluate the feasibility of gene replacement therapy for GSD-Ib, we have infused adenoviral (Ad) vector containing human G6PT (Ad-hG6PT) into G6PT-deficient (G6PT-/-) mice that manifest symptoms characteristics of the human disorder. Ad-hG6PT-infusion restores significant levels of G6PT mRNA expression in the liver, bone marrow, and spleen and corrects metabolic as well as myeloid abnormalities in G6PT-/- mice. The G6PT-/- mice receiving gene therapy exhibit improved growth; normalized serum profiles for glucose, cholesterol, triglyceride, uric acid, and lactic acid; and reduced hepatic glycogen deposition. The therapy also corrects neutropenia and lowers the elevated serum levels of granulocyte colony stimulating factor. The development of bone and spleen in the infused G6PT-/- mice is improved and accompanied by increased cellularity and normalized myeloid progenitor cell frequencies in both tissues. This effective use of gene therapy to correct metabolic imbalances and myeloid dysfunctions in GSD-Ib mice holds promise for the future of gene therapy in humans. PMID:17006547

Does attenuated skin blood flow lower sweat rate and the critical environmental limit for heat balance during severe heat exposure?

PubMed Central

Cramer, Matthew N.; Gagnon, Daniel; Crandall, Craig G.; Jay, Ollie

2016-01-01

Attenuated skin blood flow (SkBF) is often assumed to impair core temperature (Tc) regulation. Profound pharmacologically-induced reductions in SkBF (~85%) lead to impaired sweating but whether the smaller attenuations in SkBF (~20%) more associated with ageing and certain diseases lead to decrements in sweating and maximum heat loss potential is unknown. Seven healthy males (28±4y) completed a 30-min equilibration period at 41°C and a vapour pressure (Pa) of 2.57 kPa followed by incremental steps in Pa of 0.17 kPa every 6-min to 5.95 kPa. Differences in heat loss potential were assessed by identifying the critical vapour pressure (Pcrit) at which an upward inflection in Tc occurred. Three separate treatments elicited changes in plasma volume to achieve three distinct levels of SkBF: control (CON), diuretic-induced iso-osmotic dehydration to lower SkBF (DEH), and continuous saline infusion to maintain SkBF (SAL). Tc, mean skin temperature (Tsk), heart rate, mean laser-Doppler flux (forearm, thigh; LDFmean), mean local sweat rate (forearm, thigh; LSRmean), and metabolic rate were measured. In DEH, a 14.2±5.7% lower plasma volume resulted in a ~20% lower LDFmean (DEH: 139±23, CON: 176±22, SAL: 186±22 PU; P=0.034). However, LSRmean and whole-body sweat losses were unaffected by treatment throughout (P>0.482). Pcrit for Tc was similar between treatments (CON: 5.05±0.30, DEH: 4.93±0.16, SAL: 5.12±0.10 kPa; P=0.166). Further, no differences were observed in the Tsk−Ta gradient, metabolic rate, or changes in Tc (P>0.197). In conclusion, a ~20% reduction in SkBF alters neither sweat rate nor the upper limit for heat loss from the skin during non-encapsulated passive heat stress. PMID:27859929

In vitro activity and in vivo animal model efficacy of IB-367 alone and in combination with imipenem and colistin against Gram-negative bacteria.

PubMed

Simonetti, Oriana; Cirioni, Oscar; Ghiselli, Roberto; Orlando, Fiorenza; Silvestri, Carmela; Mazzocato, Susanna; Kamysz, Wojciech; Kamysz, Elzbieta; Provinciali, Mauro; Giacometti, Andrea; Guerrieri, Mario; Offidani, Annamaria

2014-05-01

The aim of our study was to evaluate the in vitro activity of IB-367 and its bactericidal effect for Pseudomonas aeruginosa and Escherichia coli, associated to a synergic study to test the antibiotic combinations between the peptide and colistin or imipenem. Minimum inhibitory concentrations (MICs), the minimum bactericidal concentrations (MBCs), the synergy test and killing study were carried out to evaluate the IB-367 activity. In the in vivo model, a wound was incised through the panniculus carnosus of BALB/c mice, and then inoculated with 5 × 107 colony-forming units of P. aeruginosa and E. coli. For each strain, the study included an infected or not infected group that did not receive any treatment, and five contaminated groups treated with local IB- 367, intraperitoneal imipenem, intraperitoneal colistin, topical IB-367 local plus intraperitoneal imipenem or intraperitoneal colistin. All isolates were inhibited by IB-367 at concentrations of 4-64 mg/l. Killing by IB-367 was shown to be very rapid: its activity on all Gram-negative bacteria was completed within a 40 min exposure period at a concentration of 2 × MIC/l. Synergy was demonstrated when IB-367 was combined with colistin or imipenem. In in vivo studies, the groups treated with topical IB-367 and intraperitoneal colistin showed the best results in terms of bacterial load inhibition either for Pseudomonas or for E. coli. The good in vitro activity and in vivo efficacy, as well as, the synergic interactions with antibiotics suggest that IB-367 is a promising candidate for potential application in the treatment of wound Gram-negative infections. Copyright © 2014 Elsevier Inc. All rights reserved.

IBS-like Symptoms in Patients with Ulcerative Colitis in Deep Remission Are Associated with Increased Levels of Serum Cytokines and Poor Psychological Well-being.

PubMed

Jonefjäll, Börje; Öhman, Lena; Simrén, Magnus; Strid, Hans

2016-11-01

Gastrointestinal symptoms (GI) compatible with irritable bowel syndrome (IBS) are common in patients with ulcerative colitis (UC) in remission. The causes of these symptoms remain to be clarified. Our aim was to investigate prevalence and factors associated with IBS-like symptoms in patients with UC in deep remission. We included 298 patients with UC and used Mayo score, sigmoidoscopy, and fecal calprotectin to define deep remission versus active disease. Presence of IBS-like symptoms according to the Rome III criteria, severity of GI, extraintestinal and psychological symptoms, stress levels, and quality of life were measured with validated questionnaires. Serum cytokines and high-sensitive C-reactive peptide were determined. The criteria for deep remission was fulfilled by 132 patients (44%) and 24 of these fulfilled the Rome III criteria for IBS (18%). Patients with UC in deep remission with IBS-like symptoms had comparable levels of GI symptoms, non-GI somatic symptoms, and quality of life as patients with active UC. The patients with UC in deep remission with IBS-like symptoms had similar levels of fecal calprotectin as patients in deep remission without IBS-like symptoms (18 versus 31 μg/g, P = 0.11), but higher levels of serum cytokines (interleukin [IL]-1β, IL-6, IL-13, IL-10 and IL-8, P < 0.05) and higher levels of anxiety (P < 0.001), depression (P = 0.02) and perceived stress (P = 0.03). IBS-like symptoms in patients with UC in deep remission are common, but not as prevalent as previously reported. Poor psychological well-being and increased serum cytokine levels, but not colonic low-grade inflammation, were associated with IBS-like symptoms.

Orange protein has a role in phytoene synthase stabilization in sweetpotato.

PubMed

Park, Seyeon; Kim, Ho Soo; Jung, Young Jun; Kim, Sun Ha; Ji, Chang Yoon; Wang, Zhi; Jeong, Jae Cheol; Lee, Haeng-Soon; Lee, Sang Yeol; Kwak, Sang-Soo

2016-09-16

Carotenoids have essential roles in light-harvesting processes and protecting the photosynthetic machinery from photo-oxidative damage. Phytoene synthase (PSY) and Orange (Or) are key plant proteins for carotenoid biosynthesis and accumulation. We previously isolated the sweetpotato (Ipomoea batatas) Or gene (IbOr), which is involved in carotenoid accumulation and salt stress tolerance. The molecular mechanism underlying IbOr regulation of carotenoid accumulation was unknown. Here, we show that IbOr has an essential role in regulating IbPSY stability via its holdase chaperone activity both in vitro and in vivo. This protection results in carotenoid accumulation and abiotic stress tolerance. IbOr transcript levels increase in sweetpotato stem, root, and calli after exposure to heat stress. IbOr is localized in the nucleus and chloroplasts, but interacts with IbPSY only in chloroplasts. After exposure to heat stress, IbOr predominantly localizes in chloroplasts. IbOr overexpression in transgenic sweetpotato and Arabidopsis conferred enhanced tolerance to heat and oxidative stress. These results indicate that IbOr holdase chaperone activity protects IbPSY stability, which leads to carotenoid accumulation, and confers enhanced heat and oxidative stress tolerance in plants. This study provides evidence that IbOr functions as a molecular chaperone, and suggests a novel mechanism regulating carotenoid accumulation and stress tolerance in plants.

Radio Observations Reveal a Smooth Circumstellar Environment Around the Extraordinary Type Ib Supernova 2012au

NASA Astrophysics Data System (ADS)

Kamble, Atish; Soderberg, Alicia M.; Chomiuk, Laura; Margutti, Raffaella; Medvedev, Mikhail; Milisavljevic, Dan; Chakraborti, Sayan; Chevalier, Roger; Chugai, Nikolai; Dittmann, Jason; Drout, Maria; Fransson, Claes; Nakar, Ehud; Sanders, Nathan

2014-12-01

We present extensive radio and X-ray observations of SN 2012au, an energetic, radio-luminous supernova of Type Ib that exhibits multi-wavelength properties bridging subsets of hydrogen-poor superluminous supernovae, hypernovae, and normal core-collapse supernovae. The observations closely follow models of synchrotron emission from a shock-heated circumburst medium that has a wind density profile (ρvpropr -2). We infer a sub-relativistic velocity for the shock wave v ≈ 0.2 c and a radius of r ≈ 1.4 × 1016cm at 25 days after the estimated date of explosion. For a wind velocity of 1000 km s-1, we determine the mass-loss rate of the progenitor to be \\dot{M} = 3.6 × 10-6 M⊙ yr-1, consistent with the estimates from X-ray observations. We estimate the total internal energy of the radio-emitting material to be E ≈ 1047 erg, which is intermediate to SN 1998bw and SN 2002ap. The evolution of the radio light curve of SN 2012au is in agreement with its interaction with a smoothly distributed circumburst medium and the absence of stellar shells ejected from previous outbursts out to r ≈ 1017 cm from the supernova site. We conclude that the bright radio emission from SN 2012au was not dissimilar from other core-collapse supernovae despite its extraordinary optical properties, and that the evolution of the SN 2012au progenitor star was relatively quiet, marked with a steady mass loss, during the final years preceding explosion.

Solar Flux Deposition And Heating Rates In Jupiter's Atmosphere

NASA Astrophysics Data System (ADS)

Perez-Hoyos, Santiago; Sánchez-Lavega, A.

2009-09-01

We discuss here the solar downward net flux in the 0.25 - 2.5 µm range in the atmosphere of Jupiter and the associated heating rates under a number of vertical cloud structure scenarios focusing in the effect of clouds and hazes. Our numerical model is based in the doubling-adding technique to solve the radiative transfer equation and it includes gas absorption by CH4, NH3 and H2, in addition to Rayleigh scattering by a mixture of H2 plus He. Four paradigmatic Jovian regions have been considered (hot-spots, belts, zones and Polar Regions). The hot-spots are the most transparent regions with downward net fluxes of 2.5±0.5 Wm-2 at the 6 bar level. The maximum solar heating is 0.04±0.01 K/day and occurs above 1 bar. Belts and zones characterization result in a maximum net downward flux of 0.5 Wm-2 at 2 bar and 0.015 Wm-2 at 6 bar. Heating is concentrated in the stratospheric and tropospheric hazes. Finally, Polar Regions are also explored and the results point to a considerable stratospheric heating of 0.04±0.02 K/day. In all, these calculations suggest that the role of the direct solar forcing in the Jovian atmospheric dynamics is limited to the upper 1 - 2 bar of the atmosphere except in the hot-spot areas. Acknowledgments: This work has been funded by Spanish MEC AYA2006-07735 with FEDER support and Grupos Gobierno Vasco IT-464-07.

Longitudinal impact of IBS-type symptoms on disease activity, healthcare utilization, psychological health, and quality of life in inflammatory bowel disease.

PubMed

Gracie, David J; Hamlin, P John; Ford, Alexander C

2018-05-01

The impact of irritable bowel syndrome (IBS)-type symptoms on the natural history of inflammatory bowel disease (IBD) is uncertain. We aimed to address this in a longitudinal study of secondary care patients. Longitudinal disease activity was defined by disease flare, escalation of medical therapy, hospitalization, or intestinal resection. The number of investigations performed and clinics attended determined healthcare utilization. Psychological well-being and quality of life were assessed using validated questionnaires. These outcomes were compared over a minimum period of 2 years between patients reporting IBS-type symptoms and patients with quiescent disease, occult inflammation, and active disease at baseline. In 360 IBD patients, there were no differences in longitudinal disease activity between patients with IBS-type symptoms and patients with quiescent disease or occult inflammation. Disease flare and escalation of medical therapy was more common in patients with active disease than in patients with IBS-type symptoms (hazard ratio (HR) = 3.16; 95% confidence interval (CI) 1.93-5.19 and HR = 3.24; 95% CI 1.98-5.31, respectively). A greater number of investigations were performed in patients with IBS-type symptoms than quiescent disease (P = 0.008), but not compared with patients with occult inflammation or active disease. Anxiety, depression, and somatization scores at follow up were higher, and quality-of-life scores lower, in patients with IBS-type symptoms when compared with patients with quiescent disease, but were similar to patients with active disease. IBS-type symptoms in IBD were associated with increased healthcare utilization, psychological comorbidity, reduced quality of life, but not adverse disease activity outcomes during extended follow-up.

Differential protective effects of immune lymphoid cells against transplanted line Ib leukemia and immune polioencephalomyelitis. [X radiation, mice

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

Duffey, P.S.; Lukasewycz, O.A.; Olson, D.S.

1978-12-01

The capacity of immune cells obtained from the major lymphoid compartments to protect C58 mice from transplanted line Ib leukemia, and from an age-dependent autoimmune CNS disease (immune polioencephalomyelitis = IPE) elicited by immunizing old C58 mice with inactivated Ib cells was quantified. Cells used for comparative adoptive protection tests were harvested from the major lymphoid compartments 14 to 15 days after young C58 mice were immunized with inactivated Ib cell preparations. Regression curves were plotted from survival data and the log/sub 10/PD/sub 50/ values were determined. Immune spleen (ISC) and peritoneal cells (IPEC) were significantly more protective against transplantedmore » Ib cells than immune lymph node (ILNC), thymic (ITC), and marrow cells (IMC). In contrast, IPEC and IMC were not protective against IPE and ITC were only marginally protective. ILNC afforded significant protection to transplantable leukemia but were only marginally protective to IPE. When ISC were treated with anti-thy 1.2 serum and complement, protection against transplanted leukemia and IPE was reduced > 99%. When donors of immune lymphoid cells were treated with 12.5 mg of cortisone acetate daily for 2 days before lymphoid cells were harvested, protection against transplanted Ib cells by ISC was reduced by approximately 90% whereas protection against IPE was totally eliminated. Considered together, these results indicate that the protective mechanisms to transplantable leukemia and IPE differ significantly in the same indicator mouse strain.« less

Analysis of read-out heating rate effects on the glow peaks of TLD-100 using WinGCF software

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

Bauk, Sabar, E-mail: sabar@usm.my; Hussin, Siti Fatimah; Alam, Md. Shah

This study was done to analyze the effects of the read-out heating rate on the LiF:Mg,Ti (TLD-100) thermoluminescent dosimeters (TLD) glow peaks using WinGCF computer software. The TLDs were exposed to X-ray photons with a potential difference of 72 kVp and 200 mAs in air and were read-out using a Harshaw 3500 TLD reader. The TLDs were read-out using four read-out heating rates at 10, 7, 4 and 1 °C s{sup −1}. It was observed that lowering the heating rate could separate more glow peaks. The activation energy for peak 5 was found to be lower than that for peakmore » 4. The peak maximum temperature and the integral value of the main peak decreased as the heating rate decreases.« less

Internal stress-induced melting below melting temperature at high-rate laser heating

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

Hwang, Yong Seok, E-mail: yshwang@iastate.edu; Levitas, Valery I., E-mail: vlevitas@iastate.edu

In this Letter, continuum thermodynamic and phase field approaches (PFAs) predicted internal stress-induced reduction in melting temperature for laser-irradiated heating of a nanolayer. Internal stresses appear due to thermal strain under constrained conditions and completely relax during melting, producing an additional thermodynamic driving force for melting. Thermodynamic melting temperature for Al reduces from 933.67 K for a stress-free condition down to 898.1 K for uniaxial strain and to 920.8 K for plane strain. Our PFA simulations demonstrated barrierless surface-induced melt nucleation below these temperatures and propagation of two solid-melt interfaces toward each other at the temperatures very close to the corresponding predicted thermodynamicmore » equilibrium temperatures for the heating rate Q≤1.51×10{sup 10}K/s. At higher heating rates, kinetic superheating competes with a reduction in melting temperature and melting under uniaxial strain occurs at 902.1 K for Q = 1.51 × 10{sup 11 }K/s and 936.9 K for Q = 1.46 × 10{sup 12 }K/s.« less

High heating rate decomposition dynamics of copper oxide by nanocalorimetry-coupled time-of-flight mass spectrometry

NASA Astrophysics Data System (ADS)

Yi, Feng; DeLisio, Jeffery B.; Nguyen, Nam; Zachariah, Michael R.; LaVan, David A.

2017-12-01

The thermodynamics and evolved gases were measured during the rapid decomposition of copper oxide (CuO) thin film at rates exceeding 100,000 K/s. CuO decomposes to release oxygen when heated and serves as an oxidizer in reactive composites and chemical looping combustion. Other instruments have shown either one or two decomposition steps during heating. We have confirmed that CuO decomposes by two steps at both slower and higher heating rates. The decomposition path influences the reaction course in reactive Al/CuO/Al composites, and full understanding is important in designing reactive mixtures and other new reactive materials.

[Using a multicomponent functional food in IBS patients with constipation a comparative controlled study].

PubMed

Pilipenko, V I; Teplyuk, D A; Shakhovskaya, A K; Isakov, V A; Vorobyova, V M; Vorobyova, I S; Sarkisyan, V A; Kochetkova, A A; Mikheeva, G A; Yudina, A V

2016-01-01

Irritable bowel syndrome (IBS) is highly prevalent functional gastrointestinal disorder associated with decrease in quality of life and a high social cost. Diet is one of several therapeutic options in IBS treatment; therefore the development and clinical evaluation of innovative functional food for IBS patients are actual. Instant drink containing 4 g inulin, 4 mg menthol and 2 mg of pyridoxine (in daily dose) has been evaluated. 49 patients 18-68 (41.5±16.5) years old fulfilling the Rome III criteria for IBS-C were randomly assigned into two groups: one received standard diet plus two drinks per day for 2 weeks and control group received standard diet. Response to therapy was recorded daily using Likert scale of abdominal pain, bloating and feeling of incomplete bowel emptying, frequency of bowel movement, Bristol stool scale, and quality of life was assessed by IBSQoL questionnaire before and after the treatment. The consumption of the drink with inulin and menthol contributed to a significant positive effect on the stool parameters (from 0.91±0.73 to 1.12±0.45 bowel movements per day in stool frequency, p=0.05, from 2.68±1.63 to 3.43±1.27 index Bristol scale, p=0.05), reduced the severity of abdominal pain (from 1.78±0.58 to 1.47?0.61 Likert scale points, p=0.05), bloating (from 2.22±0.83 to 1.53±0.71 points ofLikertscale,p= 0.01) and a sense of incomplete bowelemptying (from 2.22 ± 0.88 to 1.61± 0.81 points of Likert scale, p=0.001), as well as increased the quality of life (from 75.3± 12.0 to 83.3±6.7%, p=0.05), but a significant part of patients (10 of 25) complained the appearance of heartburn after the start of the treatment. In conclusion, the consumption of the functional drink containing inulin, menthol and pyridoxine is associated with improve in stool parameters, abdominal pain, Bristol scale index and increase in quality of life in patients with IBS-C, but produce noticeable heartburn. Changes in functional drink composition are needed to

Effects on gastrointestinal transit and antroduodenojejunal manometry after gut-directed hypnotherapy in irritable bowel syndrome (IBS).

PubMed

Lindfors, Perjohan; Törnblom, Hans; Sadik, Riadh; Björnsson, Einar S; Abrahamsson, Hasse; Simrén, Magnus

2012-12-01

Gut-directed hypnotherapy is an effective treatment in irritable bowel syndrome (IBS) but little is known about the mechanisms of action. In this study we aimed to investigate the effects on gastrointestinal motility when treating IBS with gut-directed hypnotherapy. We randomized 90 patients with IBS, refractory to standard management to receive gut-directed hypnotherapy 1 h/week for 12 weeks or supportive treatment for the same time period. Eighty-one subjects (40 hypnotherapy, 41 controls) could be evaluated by one or more of the following investigations, both before and after the intervention: gastric emptying time, small bowel transit time, colonic transit time, and antroduodenojejunal manometry. No significant differences in gastric emptying time, small bowel transit time, or colonic transit time was found when comparing the baseline and post-intervention measurements in the hypnotherapy group or in the control group. The same was true concerning the results of the antroduodenojejunal manometry. However, there was a numerical trend toward a higher number of migrating motor complexes at manometry and an accelerated gastric emptying time after hypnotherapy that did not reach statistical significance. In this study, we were not able to find evidence for long-standing effects on gastrointestinal motility as a mediator of the effects on IBS when treating the condition with gut-directed hypnotherapy. Further research to understand the mechanism of action is needed.

Effects of Adiabatic Heating on the High Strain Rate Deformation of Polymer Matrix Composites

NASA Technical Reports Server (NTRS)

Sorini, Chris; Chattopadhyay, Aditi; Goldberg, Robert K.

2017-01-01

Polymer matrix composites (PMCs) are increasingly being used in aerospace structures that are expected to experience complex dynamic loading conditions throughout their lifetime. As such, a detailed understanding of the high strain rate behavior of the constituents, particularly the strain rate, temperature, and pressure dependent polymer matrix, is paramount. In this paper, preliminary efforts in modeling experimentally observed temperature rises due to plastic deformation in PMCs subjected to dynamic loading are presented. To this end, an existing isothermal viscoplastic polymer constitutive formulation is extended to model adiabatic conditions by incorporating temperature dependent elastic properties and modifying the components of the inelastic strain rate tensor to explicitly depend on temperature. It is demonstrated that the modified polymer constitutive model is capable of capturing strain rate and temperature dependent yield as well as thermal softening associated with the conversion of plastic work to heat at high rates of strain. The modified constitutive model is then embedded within a strength of materials based micromechanics framework to investigate the manifestation of matrix thermal softening, due to the conversion of plastic work to heat, on the high strain rate response of a T700Epon 862 (T700E862) unidirectional composite. Adiabatic model predictions for high strain rate composite longitudinal tensile, transverse tensile, and in-plane shear loading are presented. Results show a substantial deviation from isothermal conditions; significant thermal softening is observed for matrix dominated deformation modes (transverse tension and in-plane shear), highlighting the importance of accounting for the conversion of plastic work to heat in the polymer matrix in the high strain rate analysis of PMC structures.

Investigations on the heat transport capability of a cryogenic oscillating heat pipe and its application in achieving ultra-fast cooling rates for cell vitrification cryopreservation.

PubMed

Han, Xu; Ma, Hongbin; Jiao, Anjun; Critser, John K

2008-06-01

Theoretically, direct vitrification of cell suspensions with relatively low concentrations ( approximately 1 M) of permeating cryoprotective agents (CPA) is suitable for cryopreservation of almost all cell types and can be accomplished by ultra-fast cooling rates that are on the order of 10(6-7) K/min. However, the methods and devices currently available for cell cryopreservation cannot achieve such high cooling rates. In this study, we constructed a novel cryogenic oscillating heat pipe (COHP) using liquid nitrogen as its working fluid and investigated its heat transport capability to assess its application for achieving ultra-fast cooling rates for cell cryopreservation. The experimental results showed that the apparent heat transfer coefficient of the COHP can reach 2 x 10(5) W/m(2).K, which is two orders of the magnitude higher than traditional heat pipes. Theoretical analyzes showed that the average local heat transfer coefficient in the thin film evaporation region of the COHP can reach 1.2 x 10(6) W/m(2).K, which is approximately 10(3) times higher than that achievable with standard pool-boiling approaches. Based on these results, a novel device design applying the COHP and microfabrication techniques is proposed and its efficiency for cell vitrification is demonstrated through numerical simulation. The estimated average cooling rates achieved through this approach is 10(6-7)K/min, which is much faster than the currently available methods and sufficient for achieving vitrification with relatively low concentrations of CPA.

Investigations on the heat transport capability of a cryogenic oscillating heat pipe and its application in achieving ultra-fast cooling rates for cell vitrification cryopreservation☆

PubMed Central

Han, Xu; Ma, Hongbin; Jiao, Anjun; Critser, John K.

2010-01-01

Theoretically, direct vitrification of cell suspensions with relatively low concentrations (~1 M) of permeating cryoprotective agents (CPA) is suitable for cryopreservation of almost all cell types and can be accomplished by ultra-fast cooling rates that are on the order of 106–7 K/min. However, the methods and devices currently available for cell cryopreservation cannot achieve such high cooling rates. In this study, we constructed a novel cryogenic oscillating heat pipe (COHP) using liquid nitrogen as its working fluid and investigated its heat transport capability to assess its application for achieving ultra-fast cooling rates for cell cryopreservation. The experimental results showed that the apparent heat transfer coefficient of the COHP can reach 2 × 105 W/m2·K, which is two orders of the magnitude higher than traditional heat pipes. Theoretical analyzes showed that the average local heat transfer coefficient in the thin film evaporation region of the COHP can reach 1.2 × 106 W/m2·K, which is approximately 103 times higher than that achievable with standard pool-boiling approaches. Based on these results, a novel device design applying the COHP and microfabrication techniques is proposed and its efficiency for cell vitrification is demonstrated through numerical simulation. The estimated average cooling rates achieved through this approach is 106–7 K/min, which is much faster than the currently available methods and sufficient for achieving vitrification with relatively low concentrations of CPA. PMID:18430413

Intestinal recruiting and activation profiles in peripheral blood mononuclear cells in response to pathogen-associated molecular patterns stimulation in patients with IBS.

PubMed

Rodríguez-Fandiño, O; Hernández-Ruíz, J; López-Vidal, Y; Charúa, L; Bandeh-Moghaddam, H; Minzoni, A; Guzmán, C; Schmulson, M

2013-11-01

Immune activation, increased Toll-like Receptors (TLR) expression, and gut epithelial diffusion of bacterial molecules have been reported in irritable bowel syndrome (IBS). Thus, we sought to relate these factors by analyzing gut homing (integrin α4β7), intestinal recruiting (CCR5) and activation (CD28) phenotypes, and the cytokines and chemokines concentration in peripheral blood T-lymphocytes stimulated with TLR-ligands. Twenty-one IBS-Rome II (1 PI-IBS) patients and 19 controls were studied. Isolated peripheral blood mononuclear cells were cultured with and without Escherichia coli lipopolysaccharide (LPS), Staphylococcus aureus peptidoglycan (PGN), and unmethylated cytosine-phosphate-guanine motifs (CpG). Phenotypes were investigated by flow cytometry and supernatant cytokines and chemokines were also measured. After LPS, CCR5 expression in CD4⁺ α4β7⁺ cells remained unchanged in IBS, but decreased in controls (p = 0.002), to lower levels than in IBS (Mean fluorescence intensity [MFI]: 1590 ± 126.9 vs 2417 ± 88.4, p < 0.001). There were less CD8(+) α4β7⁺ CCR5⁺ cells (85.7 ± 1.5 vs 90.8 ± 0.9%, p = 0.006) after LPS and CD3⁺ α4β7⁺ CCR5⁺ (40.0 ± 1.7 vs 51.2 ± 4.3%, p = 0.006) after PGN in controls. Also, after LPS, CD28 decreased in CD4⁺ α4β7⁺ CCR5⁺ in IBS (MFI: 2337 ± 47.2 vs 1779 ± 179.2, p < 0.001), but not in controls. Cytokines and chemokines were similar, except for lower IL8/CXCL8 in the unstimulated condition in IBS (4.18, 95% CI: 3.94-4.42 vs 3.77, 3.59-3.95; p = 0.006). Pathogen-associated molecular patterns stimulation of peripheral blood T cells expressing gut homing marker in IBS compared with controls resulted in an unsuccessful down-regulation of the co-expression of intestinal recruiting/residence phenotype and a state of activation. These findings support an interaction between an innate immune predisposition and microbial triggers, which may unleash or exacerbate IBS. © 2013 John Wiley & Sons Ltd.

A Distributed Perspective on Instructional Leadership in International Baccalaureate (IB) Schools

ERIC Educational Resources Information Center

Lee, Moosung; Hallinger, Philip; Walker, Allan

2012-01-01

Purpose: The purpose of this study is to provide a better understanding of how instructional leadership responsibilities are distributed in International Baccalaureate (IB) schools in East Asia. Research Design: Case studies were conducted in five international schools located in Thailand, Vietnam, Hong Kong, and China. These schools were selected…

The Gut-Brain Axis and the Microbiome: Clues to Pathophysiology and Opportunities for Novel Management Strategies in Irritable Bowel Syndrome (IBS).

PubMed

Quigley, Eamonn M M

2018-01-03

Irritable bowel syndrome (IBS) is one of the most common of all medical disorders worldwide and, while for some it represents no more than a nuisance, for others it imposes significant negative impacts on daily life and activities. IBS is a heterogeneous disorder and may well have a number of causes which may lie anywhere from the external environment to the contents of the gut lumen and from the enteric neuromuscular apparatus and the gut immune system to the central nervous system. Consequently, the paradigm of the gut-brain axis, which includes the participation of these various factors, has proven a useful model to assist clinicians and patients alike in understanding the genesis of symptoms in IBS. Now, given the widespread interest in the gut microbiome in health and disease, in general, reports of disordered enteric bacterial communities in IBS, and experimental data to indicate that components of the gut microbiota can influence brain morphology and function, as well as behavior and cognition, this concept has been extended to encompass the microbiota-gut-brain axis. The implications of this novel concept to the assessment and management of IBS will be explored in this review.

Mutation analysis of the muscarinic cholinergic receptor genes in isolated growth hormone deficiency type IB.

PubMed

Mohamadi, Ali; Martari, Marco; Holladay, Cindy D; Phillips, John A; Mullis, Primus E; Salvatori, Roberto

2009-07-01

Isolated GH deficiency (IGHD) is familial in 5-30% of patients. The most frequent form (IGHD-IB) has autosomal recessive inheritance, and it is known that it can be caused by mutations in the GHRH receptor (GHRHR) gene or in the GH gene. However, most forms of IGHD-IB have an unknown genetic cause. In normal subjects, muscarinic cholinergic stimulation causes an increase in pituitary GH release, whereas its blockade has the opposite effect, suggesting that a muscarinic acetylcholine receptor (mAchR) is involved in stimulating GH secretion. Five types of mAchR (M(1)-M(5)) exist. A transgenic mouse in which the function of the M(3) receptor was selectively ablated in the central nervous system has isolated GH deficiency similar to animals with defective GHRH or GHRHR gene. We hypothesized that mAchR mutations may cause a subset of familial IGHD. After confirming the expression of M(1)-M(5) receptor mRNA in human hypothalamus, we analyzed the index cases of 39 families with IGHD-IB for mutations in the genes encoding for the five receptors. Coding sequences for each of the five mAchRs were subjected to direct sequencing. In one family, an affected member was homozygous for a M(3) change in codon 65 that replaces valine with isoleucine (V65I). The V65I receptor was expressed in CHO cells where it had normal ability to transmit methacholine signaling. mAchR mutations are absent or rare (less than 2.6%) in familial IGHD type IB.

Comparison of breath testing with fructose and high fructose corn syrups in health and IBS

PubMed Central

Skoog, S. M.; Bharucha, A. E.; Zinsmeister, A. R.

2008-01-01

Although incomplete fructose absorption has been implicated to cause gastrointestinal symptoms, foods containing high fructose corn syrup (HFCS) contain glucose. Glucose increases fructose absorption in healthy subjects. Our hypothesis was that fructose intolerance is less prevalent after HFCS consumption compared to fructose alone in healthy subjects and irritable bowel syndrome (IBS). Breath hydrogen levels and gastrointestinal symptoms were assessed after 40 g of fructose (12% solution) prepared either in water or as HFCS, administered in double-blind randomized order on 2 days in 20 healthy subjects and 30 patients with IBS. Gastrointestinal symptoms were recorded on 100-mm Visual Analogue Scales. Breath hydrogen excretion was more frequently abnormal (P < 0.01) after fructose (68%) than HFCS (26%) in controls and patients. Fructose intolerance (i.e. abnormal breath test and symptoms) was more prevalent after fructose than HFCS in healthy subjects (25% vs 0%, P = 0.002) and patients (40% vs 7%, P = 0.062). Scores for several symptoms (e.g. bloating r = 0.35) were correlated (P ≤ 0.01) to peak breath hydrogen excretion after fructose but not HFCS; in the fructose group, this association did not differ between healthy subjects and patients. Symptoms were not significantly different after fructose compared to HFCS. Fructose intolerance is more prevalent with fructose alone than with HFCS in health and in IBS. The prevalence of fructose intolerance is not significantly different between health and IBS. Current methods for identifying fructose intolerance should be modified to more closely reproduce fructose ingestion in daily life. PMID:18221251

Comparison of breath testing with fructose and high fructose corn syrups in health and IBS.

PubMed

Skoog, S M; Bharucha, A E; Zinsmeister, A R

2008-05-01

Although incomplete fructose absorption has been implicated to cause gastrointestinal symptoms, foods containing high fructose corn syrup (HFCS) contain glucose. Glucose increases fructose absorption in healthy subjects. Our hypothesis was that fructose intolerance is less prevalent after HFCS consumption compared to fructose alone in healthy subjects and irritable bowel syndrome (IBS). Breath hydrogen levels and gastrointestinal symptoms were assessed after 40 g of fructose (12% solution) prepared either in water or as HFCS, administered in double-blind randomized order on 2 days in 20 healthy subjects and 30 patients with IBS. Gastrointestinal symptoms were recorded on 100-mm Visual Analogue Scales. Breath hydrogen excretion was more frequently abnormal (P < 0.01) after fructose (68%) than HFCS (26%) in controls and patients. Fructose intolerance (i.e. abnormal breath test and symptoms) was more prevalent after fructose than HFCS in healthy subjects (25% vs. 0%, P = 0.002) and patients (40% vs. 7%, P = 0.062). Scores for several symptoms (e.g. bloating r = 0.35) were correlated (P < or = 0.01) to peak breath hydrogen excretion after fructose but not HFCS; in the fructose group, this association did not differ between healthy subjects and patients. Symptoms were not significantly different after fructose compared to HFCS. Fructose intolerance is more prevalent with fructose alone than with HFCS in health and in IBS. The prevalence of fructose intolerance is not significantly different between health and IBS. Current methods for identifying fructose intolerance should be modified to more closely reproduce fructose ingestion in daily life.

The Double-peaked SN 2013ge: A Type Ib/c SN with an Asymmetric Mass Ejection or an Extended Progenitor Envelope

NASA Astrophysics Data System (ADS)

Drout, M. R.; Milisavljevic, D.; Parrent, J.; Margutti, R.; Kamble, A.; Soderberg, A. M.; Challis, P.; Chornock, R.; Fong, W.; Frank, S.; Gehrels, N.; Graham, M. L.; Hsiao, E.; Itagaki, K.; Kasliwal, M.; Kirshner, R. P.; Macomb, D.; Marion, G. H.; Norris, J.; Phillips, M. M.

2016-04-01

We present extensive multiwavelength (radio to X-ray) observations of the Type Ib/c supernova (SN Ib/c) SN 2013ge from -13 to +457 days relative to maximum light, including a series of optical spectra and Swift UV-optical photometry beginning 2-4 days post-explosion. This data set makes SN 2013ge one of the best-observed normal SNe Ib/c at early times—when the light curve is particularly sensitive to the progenitor configuration and mixing of radioactive elements—and reveals two distinct light curve components in the UV bands. The first component rises over 4-5 days and is visible for the first week post-explosion. Spectra of the first component have blue continua and show a plethora of moderately high velocity (˜15,000 km s-1) but narrow (˜3500 km s-1) spectroscopic features, indicating that the line-forming region is restricted. The explosion parameters estimated for the bulk explosion ({M}{{ej}} ˜ 2-3 {M}⊙ ; {E}{{K}} ˜ (1-2) × 1051 erg) are standard for SNe Ib/c, and there is evidence for weak He features at early times—in an object that would have otherwise been classified as Type Ic. In addition, SN 2013ge exploded in a low-metallicity environment (˜0.5 {Z}⊙ ), and we have obtained some of the deepest radio and X-ray limits for an SN Ib/c to date, which constrain the progenitor mass-loss rate to be \\dot{M} < 4 × 10-6 {M}⊙ yr-1. We are left with two distinct progenitor scenarios for SN 2013ge, depending on our interpretation of the early emission. If the first component is cooling envelope emission, then the progenitor of SN 2013ge either possessed an extended (≳30 {R}⊙ ) envelope or ejected a portion of its envelope in the final ≲ 1 yr before core collapse. Alternatively, if the first component is due to outwardly mixed 56Ni, then our observations are consistent with the asymmetric ejection of a distinct clump of nickel-rich material at high velocities. Current models for the collision of an SN shock with a binary companion cannot

The Double-Peaked SN 2013ge: A Type Ib/c Sn with an Asymmetric Mass Ejection or an Extended Progenitor Envelope

NASA Technical Reports Server (NTRS)

Drout, M. R.; Milisavjlevic, D.; Parrent, J.; Margutti, R.; Kamble, A.; Soderberg, A.M.; Challis, P.; Chornock, P.; Fong, W.; Frank, S.;

Biological effective dose for comparison and combination of external beam and low-dose rate interstitial brachytherapy prostate cancer treatment plans

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

Jani, Ashesh B.; Hand, Christopher M.; Lujan, Anthony E.

2004-03-31

We report a methodology for comparing and combining dose information from external beam radiotherapy (EBRT) and interstitial brachytherapy (IB) components of prostate cancer treatment using the biological effective dose (BED). On a prototype early-stage prostate cancer patient treated with EBRT and low-dose rate I-125 brachytherapy, a 3-dimensional dose distribution was calculated for each of the EBRT and IB portions of treatment. For each component of treatment, the BED was calculated on a point-by-point basis to produce a BED distribution. These individual BED distributions could then be summed for combined therapies. BED dose-volume histograms (DVHs) of the prostate, urethra, rectum, andmore » bladder were produced and compared for various combinations of EBRT and IB. Transformation to BED enabled computation of the relative contribution of each modality to the prostate dose, as the relative weighting of EBRT and IB was varied. The BED-DVHs of the prostate and urethra demonstrated dramatically increased inhomogeneity with the introduction of even a small component of IB. However, increasing the IB portion relative to the EBRT component resulted in lower dose to the surrounding normal structures, as evidenced by the BED-DVHs of the bladder and rectum. Conformal EBRT and low-dose rate IB conventional dose distributions were successfully transformed to the common 'language' of BED distributions for comparison and for merging prostate cancer radiation treatment plans. The results of this analysis can assist physicians in quantitatively determining the best combination and weighting of radiation treatment modalities for individual patients.« less