348 research outputs found

    Seasonal prediction of end-of-dry-season watershed behavior in a highly interconnected alluvial watershed in northern California

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    In undammed watersheds in Mediterranean climates, the timing and abruptness of the transition from the dry season to the wet season have major implications for aquatic ecosystems. Of particular concern in many coastal areas is whether this transition can provide sufficient flows at the right time to allow passage for spawning anadromous fish, which is determined by dry season baseflow rates and the timing of the onset of the rainy season. In (semi-) ephemeral watershed systems, these functional flows also dictate the timing of full reconnection of the stream system. In this study, we propose methods to predict, approximately 5 months in advance, two key hydrologic metrics in the undammed rural Scott River watershed in northern California. The two metrics are intended to characterize (1) the severity of a dry year and (2) the relative timing of the transition from the dry to the wet season. The ability to predict these metrics in advance could support seasonal adaptive management. The first metric is the minimum 30 d dry season baseflow volume, Vmin, which occurs at the end of the dry season (September–October) in this Mediterranean climate. The second metric is the cumulative precipitation, starting 1 September, necessary to bring the watershed to a “full” or “spilling” condition (i.e., initiate the onset of wet season storm- or baseflows) after the end of the dry season, referred to here as Pspill. As potential predictors of these two metrics, we assess maximum snowpack, cumulative precipitation, the timing of the snowpack and precipitation, spring groundwater levels, spring river flows, reference evapotranspiration, and a subset of these metrics from the previous water year. Though many of these predictors are correlated with the two metrics of interest, we find that the best prediction for both metrics is a linear combination of the maximum snowpack water content and total October–April precipitation. These two linear models could reproduce historical values of Vmin and Pspill with an average model error (RMSE) of 1.4 Mm3 per 30 d (19.4 cfs) and 25.4 mm (1 in.), corresponding to 49 % and 37 % of mean observed values, respectively. Although these predictive indices could be used by governance entities to support local water management, careful consideration of baseline conditions used as a basis for prediction is necessary.</p

    Investigation of A1g phonons in YBa2Cu3O7 by means of LAPW atomic-force calculations

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    We report first-principles frozen-phonon calculations for the determination of the force-free geometry and the dynamical matrix of the five Raman-active A1g modes in YBa2Cu3O7. To establish the shape of the phonon potentials atomic forces are calculated within the LAPW method. Two different schemes - the local density approximation (LDA) and a generalized gradient approximation (GGA) - are employed for the treatment of electronic exchange and correlation effects. We find that in the case of LDA the resulting phonon frequencies show a deviation from experimental values of approximately -10%. Invoking GGA the frequency values are significantly improved and also the eigenvectors are in very good agreement with experimental findings.Comment: 15 page

    Structure optimization effects on the electronic properties of Bi2_2Sr2_2CaCu2_2O8_8

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    We present detailed first-principles calculations for the normal state electronic properties of the high TC_C superconductor Bi2_2Sr2_2CaCu2_2O8_8, by means of the linearized augmented plane wave (LAPW) method within the framework of density functional theory (DFT). As a first step, the body centered tetragonal (BCT) cell has been adopted, and optimized regarding its volume, c/ac/a ratio and internal atomic positions by total energy and force minimizations. The full optimization of the BCT cell leads to small but visible changes in the topology of the Fermi surface, rounding the shape of CuO2_2 barrels, and causing both the BiO bands, responsible for the pockets near the \textit{\=M} 2D symmetry point, to dip below the Fermi level. We have then studied the influence of the distortions in the BiO plane observed in nature by means of a 2Ă—2\sqrt{2}\times\sqrt{2} orthorhombic cell (AD-ORTH) with BbmbBbmb space group. Contrary to what has been observed for the Bi-2201 compound, we find that for Bi-2212 the distortion does not sensibly shift the BiO bands which retain their metallic character. As a severe test for the considered structures we present Raman-active phonon frequencies (q=0q = 0) and eigenvectors calculated within the frozen-phonon approximation. Focussing on the totally symmetric Ag_{g} modes, we observe that for a reliable attribution of the peaks observed in Raman experiments, both cc- and a-axis vibrations must be taken into account, the latter being activated by the in-plane orthorhombic distortion.Comment: 22 pages, 4 figure

    Preservation of Truncal Genomic Alterations in Clear Cell and Papillary Renal Cell Carcinomas with Sarcomatoid Features: An Intra- and Intertumoral, Multifocal Fluorescence in Situ Hybridization Analysis Reveals Limited Genetic Heterogeneity

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    Understanding tumor genomic heterogeneity may offer vital information in an age of targeted therapy for renal cell carcinoma. We sought to investigate hallmark truncal chromosomal alterations between conventional, sarcomatoid, and matched metastatic tumor foci in clear cell and papillary renal cell carcinomas. A retrospective review identified 58 cases including clear cell (CCRCC) and papillary renal cell carcinomas (PRCC). All cases contained sarcomatoid transformation. Additionally, 10 of 58 patients had matched metastatic disease available for analysis. Three separate foci of conventional and sarcomatoid morphologies were analyzed in each tumor using dual color interphase fluorescence in situ hybridization. In the CCRCC cohort, hallmark chromosome 3p deletion was identified in 71% of cases (37/52). Complete concordance of chromosomal status between intratumoral foci in sarcomatoid and conventional foci was 89% and 86%, respectively. Overall chromosome 3p status between matched conventional and sarcomatoid morphologies was identified in 98% of cases (51/52). Hallmark 3p deletion was present in 91% of CCRCC metastatic samples (10/11) and was concordant with the matched primary CCRCC tumor in 91% (10/11). In the PRCC cohort, trisomy 7 and 17 was identified in all six cases (6/6). Complete concordance between intratumoral foci of trisomy 7 and 17 was 83% (5/6). Trisomy 7 and 17 were identified in all metastatic PRCC samples with 100% concordance with the matched primary tumor. These data show the relative preservation of truncal chromosomal abnormalities between conventional and sarcomatoid morphologic as well as matched metastatic settings

    Transperitoneal laparoscopic right radical nephrectomy for renal cell carcinoma and end-stage renal disease: a case report

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    Nephron-sparing surgery (partial nephrectomy) results are similar to those of radical nephrectomy for small (<4 cm) renal tumors. However, in patients with end-stage renal disease, radical nephrectomy emerges as a more efficient treatment for localized renal cell cancer. Laparoscopic radical nephrectomy (LRN) increasingly is being performed. The objective of the present study was to present a case of a patient under hemodialysis who was submitted to LRN for a small renal mass and discuss the current issues concerning this approach. It appears that radical nephrectomy should be the standard treatment in dialysis patients even for small tumors. The laparoscopic technique is associated with acceptable cancer-specific survival and recurrence rate along with shorter hospital stay, less postoperative pain and earlier return to normal activities

    Solitary fibrous tumour of the genitourinary tract: a clinicopathological study of 11 cases and their association with the NAB2-STAT6 fusion gene

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    Aims To characterise clinicopathological features and clinical outcomes of the genitourinary tract solitary fibrous tumours, incorporating NAB2-STAT6 gene fusion status. Methods The presence of the molecular hallmark NAB2-STAT6 gene fusion and for the defining fusion partner product STAT6 was assessed in 11 cases of the genitourinary tract solitary fibrous tumours. NAB2-STAT6 gene fusion analysis was performed using a break-apart fluorescence in situ hybridisation (FISH) probe using a probe cocktail with Bacterial artificial chromosome (BAC) clones for STAT6 and NAB2. Results Eleven solitary fibrous tumours were diagnosed in eight male patients and three female patients with a mean age of 46 years (range: 11–64 years). Four of the tumours had malignant histological features, and three were considered moderate risk for metastasis. With a mean follow-up time of 61 months, 1 recurred locally and 2 presented at distant metastatic sites. Using a break-apart FISH probe cocktail, we found the NAB2-STAT6 gene fusion and nuclear STAT6 expression in 58% and 91% of cases, respectively. However, the NAB2-STAT6 fusion status was not correlated with STAT6 expression or useful in discriminating between malignant histological features or subsequent clinical outcomes in the genitourinary solitary fibrous tumours. Conclusions A subset of solitary fibrous tumours of the genitourinary tract behaved aggressively. Using a break-apart FISH probe cocktail, we found the NAB2-STAT6 gene fusion in 64% of cases. However, the NAB2-STAT6 fusion status was not correlated with STAT6 expression or useful in discriminating between low-risk or high-risk tumours and subsequent clinical outcomes

    Promoting early language development in the Arab world and sustainable development goals 3, 4, 10 and 17

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    PURPOSE: This commentary describes a multi-national project which addresses gaps in the design and delivery of health and education services in Arabic-speaking countries in relation to early language development, with a focus on Egypt, Jordan, Lebanon and the Palestinian Territories. This includes: (1) co-production with early years professionals and NGOs of approaches to support early language development; (2) development and standardisation of tools to identify monolingual and multilingual Arabic-speaking children at risk of poor language development; and (3) examination of language development in refugee communities. RESULT: The importance of inter-professional partnership and the inclusion of families in planning support for oral language development is highlighted. Arabic versions of the Communicative Development Inventory (CDI) Toddler were developed, and data collected from 1074 Egyptian, Jordanian and Palestinian monolingual infants aged 8-30 months. Data from 201 age-matched Palestinian infants in Lebanese refugee camps highlight inequalities resulting from limited maternal educational opportunities. Data from 230 multilingual Lebanese 2-year-olds enable the interpretation of CDI scores as a function of language exposure. CONCLUSION: This work contributes to the promotion of robust language development for all Arabic-speaking children. This commentary focusses on sustainable development goal (SDG) 3, SDG 4, SDG 10 and SDG 17

    Guidance on the assessment of the safety of feed additives for the environment

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    This guidance document is intended to assist the applicant in the preparation and the presentation of an application, as foreseen in Article 7.6 of Regulation (EC) No&nbsp;1831/2003, for the authorisation of additives used in animal nutrition. It specifically covers the assessment of the safety for the environment. (Table presented.)

    Measurement of CNGS muon neutrino speed with Borexino

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    We have measured the speed of muon neutrinos with the Borexino detector using short-bunch CNGS beams. The final result for the difference in time-of-flight between a =17 GeV muon neutrino and a particle moving at the speed of light in vacuum is {\delta}t = 0.8 \pm 0.7stat \pm 2.9sys ns, well consistent with zero.Comment: 6 pages, 5 figure
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