Analysis of a low-angle annular expander nozzle

An experimental and numerical analysis of a low-angle annular expander nozzle is presented to observe the variance in shock structure within the flow field. A RANS-based axisymmetric numerical model was used to evaluate flow characteristics and the model validated using experimental pressure readings and schlieren images. Results were compared with an equivalent converging-diverging nozzle to determine the capability of the wake region in varying the effective area of a low-angle design. Comparison of schlieren images confirmed that shock closure occurred in the expander nozzle, prohibiting the wake region from affecting the area ratio. The findings show that a low angle of deflection is inherently unable to influence the effective area of an annular supersonic nozzle design

Successful Conversion From Parenteral Paricalcitol to Pulse Oral Calcitriol for the Management of Secondary Hyperparathyroidism in Hemodialysis Patients

OBJECTIVE: The management of hyperparathyroidism in hemodialysis patients involves the administration of phosphate binders, vitamin D receptor activators and calcimimetics. Intravenous paricalcitol has been preferred over oral calcitriol as it may cause less hypercalcemia and hyperphosphatemia. However, there is little data looking at the efficacy and tolerability of oral calcitriol in the calcimimetic era particularly in a real practice-based experience. The XXX free-standing dialysis center converted from routine intravenous paricalcitol to oral calcitriol due to pharmacy purchasing preferences. We report the efficacy, safety and cost of such a change. SETTING: XXX dialysis center SUBJECTS: 93 pre conversion intravenous paricalcitol and 91 post conversion oral calcitriol INTERVENTION: Conversion to in-center, pulse, oral calcitriol (0.25 mcg =1 mcg paricalcitol) 3 times a week from intravenous paracalcitol. Additional dose adjustments were made by the nephrologists based on clinical indications. MAIN OUTCOME MEASURE: 5-month average serum calcium, phosphorous, and intact parathyroid hormone levels and cardiovascular events pre and post transition. RESULTS: There were 93 patients on intravenous paricalcitol between April 2013 and August 2013, of which 74 converted to oral calcitriol and were included in the post-conversion group evaluated between October 2013 and February 2014. An additional 17 new patients had initiated calcitriol such that 91 patients were on oral therapy in the post-conversion period. Sevelamer use increased from 41 (44.1%) patients pre-conversion to 48 (52.7%) post-conversion, while calcium acetate use significantly dropped from 62 (66.7%) to 46 (50.5%) (p=0.026). Cinacalcet use dropped slightly from 37 (39.7%) patients pre- to 35 (38.4%) post-conversion. Average serum calcium, phosphorus and intact parathyroid hormone levels remained unchanged after conversion. Percent of values within KDOQI guidelines were similarly maintained. Estimated vitamin D cost savings were $564 per person/year. No increase in the incidence of cardiovascular events was observed. CONCLUSIONS: We conclude that in-center distributed pulse oral calcitriol may be an effective, safe and economical treatment option for the management of hyperparathyroidism in hemodialysis patients

Toll-Like Receptor 4 Regulates Chronic Stress-Induced Visceral Pain in Mice

Background Functional gastrointestinal disorders, which have visceral hypersensitivity as a core symptom, are frequently comorbid with stress-related psychiatric disorders. Increasing evidence points to a key role for toll-like receptor 4 (TLR4) in chronic pain states of somatic origin. However, the central contribution of TLR4 in visceral pain sensation remains elusive. Methods With pharmacological and genetic approaches, we investigated the involvement of TLR4 in the modulation of visceral pain. The TLR4-deficient and wild-type mice were exposed to chronic stress. Visceral pain was evaluated with colorectal distension. Protein expression levels for TLR4, Cd11b, and glial fibrillary acidic protein (glial cells markers) were quantified in the lumbar region of the spinal cord, prefrontal cortex (PFC), and hippocampus. To evaluate the effect of blocking TLR4 on visceral nociception, TAK-242, a selective TLR4 antagonist, was administered peripherally (intravenous) and centrally (intracerebroventricular and intra-PFC) (n = 10–12/experimental group). Results The TLR4 deficiency reduced visceral pain and prevented the development of chronic psychosocial stress-induced visceral hypersensitivity. Increased expression of TLR4 coupled with enhanced glia activation in the PFC and increased levels of proinflammatory cytokines were observed after chronic stress in wild-type mice. Administration of a TLR4 specific antagonist, TAK-242, attenuated visceral pain sensation in animals with functional TLR4 when administrated centrally and peripherally. Moreover, intra-PFC TAK-242 administration also counteracted chronic stress-induced visceral hypersensitivity. Conclusions Our results reveal a novel role for TLR4 within the PFC in the modulation of visceral nociception and point to TLR4 as a potential therapeutic target for the development of drugs to treat visceral hypersensitivity.The work described herein was supported by the Alimentary Pharmabiotic Centre, funded by Science Foundation Ireland (SFI), through the Irish Government’s National Development Plan. The authors and their work were supported by SFI (Grant Numbers 02/CE/B124 and 07/CE/B1368 and SFI/12/RC/2273)

Winter Rye Cover Crop Biomass Production, Degradation, and Nitrogen Recycling

Winter rye (Secale cereale L.) cover crop (RCC) use in corn (Zea mays L.) and soybean [Glycine max. (L.) Merr.] production can alter N dynamics compared to no RCC. The objectives of this study were to evaluate RCC biomass production (BP) and subsequent RCC degradation (BD) and N recycling in a no-till corn–soybean (CS) rotation. Aboveground RCC was sampled at spring termination for biomass dry matter (DM), C, and N. To evaluate BD and remaining C and N, RCC biomass was put into nylon mesh bags, placed on the soil surface, and collected multiple times over 105 d. Treatments included rye cover crop following soybean (RCC-FS) and corn (RCC-FC), and prior-year N applied to corn. Overall, the RCC BP and N was low due to low soil profile NO3–N. Across sites and years, the greatest BP was with RCC-FC that received 225 kg N ha–1 (1280 kg DM ha–1), with similar N uptake as with RCC-FS (27 kg N ha–1). The RCC biomass and N remaining decreased over time following an exponential decay. An average 62% biomass with RCC-FS and RCC-FC degraded after 105 d; however, N recycled was greater with RCC-FS than RCC-FC [22 (80%) vs. 14 (64%) kg N ha–1, respectively], and was influenced by the RCC C/N ratio. The RCC did not recycle an agronomically meaningful amount of N, which limited N that could potentially be supplied to corn. Rye cover crops can conserve soil N, and with improved management and growth, recycling of crop-available N should increase

Obesity Takes Its Toll on Visceral Pain: High-Fat Diet Induces Toll-Like Receptor 4- Dependent Visceral Hypersensitivity

Exposure to high-fat diet induces both, peripheral and central alterations in TLR4 expression. Moreover, functional TLR4 is required for the development of high-fat diet-induced obesity. Recently, central alterations in TLR4 expression have been associated with the modulation of visceral pain. However, it remains unknown whether there is a functional interaction between the role of TLR4 in diet-induced obesity and in visceral pain. In the present study we investigated the impact of long-term exposure to high-fat diet on visceral pain perception and on the levels of TLR4 and Cd11b (a microglial cell marker) protein expression in the prefrontal cortex (PFC) and hippocampus. Peripheral alterations in TLR4 were assessed following the stimulation of spleenocytes with the TLR4-agonist LPS. Finally, we evaluated the effect of blocking TLR4 on visceral nociception, by administering TAK-242, a selective TLR4-antagonist. Our results demonstrated that exposure to high-fat diet induced visceral hypersensitivity. In parallel, enhanced TLR4 expression and microglia activation were found in brain areas related to visceral pain, the PFC and the hippocampus. Likewise, peripheral TLR4 activity was increased following long-term exposure to high-fat diet, resulting in an increased level of pro-inflammatory cytokines. Finally, TLR4 blockage counteracted the hyperalgesic phenotype present in mice fed on high-fat diet. Our data reveal a role for TLR4 in visceral pain modulation in a model of diet-induced obesity, and point to TLR4 as a potential therapeutic target for the development of drugs to treat visceral hypersensitivity present in pathologies associated to fat diet consumption

Ototoxicity of cisplatin plus standard radiation therapy vs. accelerated radiation therapy in glioblastoma patients

Purpose : To assess the effect of cisplatin (CDDP) plus concurrent radiation therapy on hearing loss. Methods : 451 patients with glioblastoma multiforme (GBM) were randomly assigned after surgery to: Arm A: Carmustine (BCNU) + standard radiation therapy (SRT); Arm B: BCNU + accelerated radiation therapy (ART: 160 cGy twice daily for 15 days); Arm C: CDDP + BCNU + SRT; or Arm D: CDDP + BCNU + ART. Patients on arms C and D received audiograms at baseline, and prior to the start of RT, and prior to cycles 3 and 6. Otologic toxicities were recorded at each visit. Results : 56% of patients had hearing loss at baseline. 13% and 50% of patients experienced worsening ototoxicity after 1 year of treatment in arms A and B vs. C and D, respectively, with 13% of those on arms C and D experiencing significant ototoxicity (≥ grade 3) at 6 months. Increasing age was associated with an increased risk of ototoxicity. Conclusions : Increased exposure to CDDP increases the risk of ototoxicity over time. Older patients are more susceptible to hearing loss with CDDP. The low proportion of patients with clinically significant ototoxicity suggests that baseline screening is unnecessary in GBM patients.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/43476/1/11060_2005_Article_9049.pd

An epidemiologic approach for using social media in public health interventions

Participation in social media particularly in urban centers is growing rapidly. Understanding how information in social media can modify public health behaviors and how social media can be mined to make meaningful public health intervention shall be highly useful as social media use expands. The specific focus of this thesis is to describe how social media on Yelp.com can be mined to gain meaningful public health surveillance that is predictive of real world health code violation. The Second aim of this thesis is to survey an urban area with a high concentration of Yelp users to identify how Yelp use and value of information on Yelp can modify the health behavior of restaurant selection and modify odds of food borne illness. In our analysis of the predictive power of social media data mined from Yelp.com we found that keywords like “vomit” and “DIRTY” were predictive of substandard health code rating (<80) with Odds Ratio of (45.4), and (3.68) respectively. The logistic regression model used had Sensitivity, Specificity, Positive Predictive Value, and Area under the Receiver Operator Curve of .72, .44, .61, and .78 respectively. Our Survey of an urban area with a high concentration of Yelp users found that those Yelp users that valued Yelp’s measurement of quality “Stars” the most had increased odds of reported food borne illness (1.01-2.54). We also found that despite Yelp.com’s “partnership” with public health officials in San Francisco and their agreement to present public health data on Yelp.com only 10% of respondents knew public health data was posted for restaurants on Yelp.com. Our results show us that knowledge of health code violations like employee hand washing and presence of vermin decreased respondent desire to select restaurant more than knowledge of health code rating. This is important to note as yelp only presents health code ratings along the restaurants on its site. The findings of the analysis conducted in this thesis allow public health officials to improve the effectiveness of surveillance of restaurants for food borne illness risk factors, and improve partnerships with social media companies like yelp.com to better communicate public health findings and change public health behaviors