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Aquifer denitrification is among the most poorly constrained fluxes in global and regional nitrogen budgets. The few direct measurements of denitrification in groundwaters provide limited information about its spatial and temporal variability, particularly at the scale of whole aquifers. Uncertainty in estimates of denitrification may also lead to underestimates of its effect on isotopic signatures of inorganic N, and thereby confound the inference of N source from these data. In this study, our objectives are to quantify the magnitude and variability of denitrification in the Upper Floridan Aquifer (UFA) and evaluate its effect on N isotopic signatures at the regional scale. Using dual noble gas tracers (Ne, Ar) to generate physical predictions of N2 gas concentrations for 112 observations from 61 UFA springs, we show that excess (i.e. denitrification-derived) N2 is highly variable in space and inversely correlated with dissolved oxygen (O2). Negative relationship between O2 and δ15NNO3 across a larger dataset of 113 springs, well-constrained isotopic fractionation coefficients, and strong 15N : 18O covariation further support inferences of denitrification in this uniquely organic-matter-poor system. Despite relatively low average rates, denitrification accounted for 32% of estimated aquifer N inputs across all sampled UFA springs. Back-calculations of source δ 15NNO3 based on denitrification progression suggest that isotopically-enriched nitrate (Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed) in many springs of the UFA reflects groundwater denitrification rather than urban- or animal-derived inputs. [ABSTRACT FROM AUTHOR]

Background: Computerized physician order entry systems are known to improve patient safety in acute-care hospitals. However, as clinicians frequently override drug interaction and allergy alerts, their value in ambulatory care remains uncertain.Objective: The purpose of the study was to examine whether ambulatory care clinicians were more likely to accept drug-drug interaction alerts that an expert panel judged to be of high clinical value.Study Design: We convened an expert panel to examine drug-drug interaction alerts generated by 2872 clinicians in Massachusetts, Pennsylvania and New Jersey who used a common electronic prescribing system between 1 January 2006 and 30 September 2006. We selected 120 representative drug interaction alerts from the most commonly encountered class-class interactions.Measurements: The expert panel rated each alert based on the following categories: (i) strength of the scientific evidence; (ii) probability that the interaction would result in an adverse drug event (ADE); (iii) severity of typical and most serious ADEs; (iv) the likelihood that a clinician could act on the information; and (v) the overall value of the alert to the average primary care clinician. We then used multivariate regression techniques to examine the relationship between the alert acceptance rate and the expert panel's mean rating of each category.Results: The decision of clinicians to accept drug interaction alerts increased (relative to a baseline alert acceptance rate of 8.8%) by 2.7% (95% CI 0.4, 5.1) for interactions that panelists judged would result in an ADE, by 2.3% (95% CI 0.9, 3.7) when primary care providers (PCPs) lacked prior knowledge about the information presented in the alert, and by 3.3% (95% CI 0.9, 5.8) when the PCP could readily act on the information provided in the alert.Conclusion: The value of electronic drug interaction alerts is influenced heavily by clinicians' judgements about the clinical value of the alert. Expert judgement should be taken into account when developing electronic decision support. [ABSTRACT FROM AUTHOR]

Ultrafiltration (UF) failure is a consequence of long-term peritoneal dialysis (PD). Fibrosis, angiogenesis, and vasculopathy are causes of this functional disorder after 3–8 years on PD. Epithelial-to-mesenchymal transition (EMT) of mesothelial cell (MC) is a key process leading to peritoneal fibrosis with functional deterioration. Our purpose was to study the peritoneal anatomical changes during the first months on PD, and to correlate them with peritoneal functional parameters. We studied 35 stable PD patients for up to 2 years on PD, with a mean age of 45.3±14.5 years. Seventy-four percent of patients presented loss of the mesothelial layer, 46% fibrosis (>150 μm) and 17% in situ evidence of EMT (submesothelial cytokeratin staining), which increased over time. All patients with EMT showed myofibroblasts, while only 36% of patients without EMT had myofibroblasts. The number of peritoneal vessels did not vary when we compared different times on PD. Vasculopathy was present in 17% of the samples. Functional studies were used to define the peritoneal transport status. Patients in the highest quartile of mass transfer area coefficient of creatinine (Cr-MTAC) (>11.8 ml min−1) showed significantly higher EMT prevalence (P=0.016) but similar number of peritoneal vessels. In the multivariate analysis, the highest quartile of Cr-MTAC remained as an independent factor predicting the presence of EMT (odds ratio 12.4; confidence interval: 1.6–92; P=0.013) after adjusting for fibrosis (P=0.018). We concluded that, during the first 2 PD years, EMT of MCs is a frequent morphological change in the peritoneal membrane. High solute transport status is associated with its presence but not with increased number of peritoneal vessels.Kidney International (2008) 73, S26–S33; doi:10.1038/sj.ki.5002598 [ABSTRACT FROM AUTHOR]

The article presents the court case between the Boyd County High School Gay Straight Alliances and the Board of Education in Boyd County, Kentucky. The plaintiff sued alleging that by forcing students to attend mandatory diversity training that promotes a respectful coexistence with homosexuals. The court established that schools could regulate student speech if the speech would materially and substantially interfere with the operation of the school or abridge the rights of other students. The court decided that by misapplying the constitutional standards concerning different types of school speech, it will diminish the impact of its decision for gay rights advocates.

A case of ossifying fibromyxoid tumor (OFMT) evaluated during an intraoperative pathological consultation is presented. The patient, a 70-year-old woman was being followed because of a tumor in the left buttock. Cytological smears were obtained after scrapping the tumoral cut surface and revealed a myxoid background with fragments composed of a denser, fibrillar metachromatic stroma with accompanying round to oval tumoral nuclei and no vessels. Single cells were predominantly monomorphic with a round to oval morphology and scarce cytoplasm. The most relevant feature of the tumor was its peripheral, plaque-like, calcified consistency. The review of the cytological descriptions of four cases revealed similar findings that can be presumed as those of a low-grade myxoid tumor of round to oval cells. A specific recognition of OFMT based solely on cytological features seems difficult. However, when such features are coupled with characteristic radiological findings (peripheral calcification) this entity must be considered. [ABSTRACT FROM AUTHOR]

The cleaved {1100} mirror facets of III-nitride ridge waveguide laser diodes grown on free-standing GaN substrates have been characterized using atomic force microscopy. The measurements indicate that the exposed facets are atomically smooth and therefore they have a much lower roughness than has been reported for cleaved surfaces of III-nitride heterostructures grown on other substrates. Individual heterostructure layers—including InGaN quantum wells only 3 nm thick—could be identified from small variations in the height of the exposed surface. These variations are attributed primarily to the partial relaxation of strained layers at the free surface. [ABSTRACT FROM AUTHOR]

Unlabelled: We describe a 12-year-old patient with a primary pulmonary mass in the left upper lung. The diagnosis of inflammatory pseudotumour was suspected preoperatively. After pathological examination and complete clinical evaluation, a diagnosis of malignant primary pulmonary fibrous histiocytoma was established. This is a very uncommon primary neoplasm of the lung and to our knowledge only five paediatric cases have been reported. Because of the rarity of these sarcomas and histological similarities to benign inflammatory pseudotumour, care must be taken to avoid confusion between the two disorders particularly in intra-operative frozen sections.Conclusion: Primary malignant fibrous histiocytoma of the lung is an uncommon tumour that should be considered in the differential diagnosis of pulmonary neoplasms of childhood. The histological diagnosis can be difficult due to the similarities with inflammatory pseudotumour. [ABSTRACT FROM AUTHOR]

There has been increased interest in the use of by-products (BP) for ruminant feeds, yet a deficit in information regarding nutrient content of these feeds exist. The objective of this study was to assess the effect of different rumen fluid inoculum on in vitro digestibility, including Dry Matter Digestibility (DMD); Organic Matter Digestibility (OMD); Crude Protein Digestibility (CPD); Neutral Detergent Fibre digestibility (NDFd); Acid Detergent Fibre digestibility (ADFd), and fermentation parameters of four commonly used BP feeds: Maize Distillers (MD); Wheat Distillers (WD); Palm Kernel (PK) and Soya Hulls (SH). Rumen inoculum was sourced from six rumenfistulated continental heifers blocked on weight and age and fed one of two divergent diets vis. 50: 50 silage: concentrate (C, rumen inoculum) on a dry matter (DM) basis or grass only (G, rumen inoculum). In vitro incubation trials were carried out with the rumen simulation technique (RUSITEC). The dietary in vitro treatments consisted of 60% silage (18% DM, 13.37% CP, 51.5% NDF and 37.39% ADF) and 40% of the BP ingredient on a DM basis. These were incubated in one of two rumen inoculum (C or G), replicated three times and distributed evenly among three eight vessel RUSITEC units, resulting in a 2x4 factorial design. No interaction was detected (P > 0.05) between rumen inoculum and BP ingredient for any of the parameters examined. Rumen fluid inoculum had no effect on the digestibility of DM, OM, CP, NDF or ADF of concentrate or whole diet; pH; daily gas production; total VFA or molar concentrations of individual VFA proportions (P > 0.05). However, ammonia production was higher (P < 0.05) in the C compared to G derived inoculum. The DMD of the BP were: WD (70%); MD (60%); PK (53%) and SH (34%) (P < 0.0001). By-product ingredient had no effect on gas production, pH or total VFA production. However, concentration of individual VFA varied with by-product ingredient. Palm kernel and SH exhibited the highest acetate: propionate (A: P) ratio of 2.41 and 2.34 respectively. Wheat distillers resulted in the lowest A: P ratio of 2.08. Daily ammonia production was affected by by-product ingredient, resulting in WD > MD > PK >SH (P < 0.01). In conclusion, in the RUSITEC culture system the in vitro digestibility and fermentation profile of by-product feeds are consistent and unaffected by rumen inoculum when sourced from divergent diets within a single animal species. [ABSTRACT FROM AUTHOR]

The article discusses the cytological features of both monolayered swirls, normally associated with thyroid papillary carcinoma. Topics include similar cellular swirls and swirl-like structures in fine needle aspirates from papillary renal cell carcinoma, and their relation to the common papillary architectural configuration of both neoplasms.

The objective of this study was to investigate the effects of by-product (BP) inclusion and linseed oil (LO) on diet digestibility, fermentation pattern and methane production using the rumen simulation technique (Rusitec), with perennial ryegrass pasture as the main forage source. Dietary treatment consisted of a supplementary concentrate (factor I) containing either 35% BP (BP35) or 95% BP (BP95) with and without 6% LO inclusion (factor II), thereby culminating in a 2 (concentrate; BP 35 or BP95) x 2 (LO; + or -) factorial arrangement. Dietary in vitro treatments consisted of a 50:50 perennial ryegrass based pasture (PRG) and one the four supplementary concentrates. Treatments were randomly allocated to sixteen fermentation vessels. The in vitro incubation trial involved of a single incubation period lasting 14 d consisting of 10 d adaption and 4 d sampling period. The DM digestibility of the concentrate treatments were: BP35 (68.9%); BP35+oil (68.7%); BP95 (57.4%) and BP 95+oil (54.4%). In general, concentrate that contained lower levels of BP had a higher digestibility parameters (DM, OM, CP, NDF and ADF) than the concentrates that contained a higher BP inclusion (P <0.0001). No significant difference was recorded in pH or NH3-N production for any treatments examined (P > 0.10). Production of volatile fatty acids (VFA) was highest for the low BP diets (BP35; P < 0.05) relative to the BP95. Acetic acid proportion (P < 0.05) and acetate:proprionate ratio (P < 0.05) was greatest in the BP95 concentrate compared to the BP35 diet. Methane production (when expressed as production per day or in terms of production per organic matter digested) was affected (P < 0.05) by BP concentrate type and LO supplementation. Addition, of LO reduced methane (CH4) for both BP concentrate types with BP95+LO having the lowest CH4 production, BP35+LO and BP95 intermediate and BP35 having the highest CH4 production, respectively. Under in vitro conditions, the inclusion of BP and addition of supplementary LO to a concentrate supplemented grass based diet of ruminants can effectively reduce CH4 production. [ABSTRACT FROM AUTHOR]

Adenocarcinoma with massive lymphocyte infiltration is a rare pulmonary neoplasm with few reported cases. It seems to have a better outcome than conventional adenocarcinomas, but it is still not clear if it constitutes a specific clinicopathological entity. We report a case in which cytological studies were available. The small size of the tumor, abundant lymphocyte population, well-differentiated morphology of the neoplasm and scarcity of atypical cells resulted in a difficult cytological diagnosis. This entity should be considered when evaluating pulmonary lesions with abundant lymphocytes. Not all carcinomas with prominent lymphoid stroma show the high-grade, pleomorphic morphology of lymphoepithelioma-like carcinomas. [ABSTRACT FROM AUTHOR]

Describes the findings in a case of fine needle aspiration cytology of pulmonary rheumatoid nodule. Presence of mononuclear and occasionally multinucleated histiocytes; Cytomorphology; Main differential diagnosis.

A letter to the editor is presented in response to the article "Role of cell block preparation in Warthin's tumor," by R. Patnayak, A. Jena, and Kumar Chowhan.