Sensitivity plots for WIMP modulation searches

Prospects of WIMP searches using the annual modulation signature are discussed on statistical grounds, introducing sensitivity plots for the WIMP-nucleon scalar cross section.Comment: 3 pages, 2 figures, talk given at TAUP'99, september 199

Structure and functional prediction of a microbial community involved in a full-scale biofilter treating wastewater odor.

Abstract: The efficiency of biofilters depends on the microbial community, so it is crucial to understand the structural/functional dynamics and identify the key microbial genera associated with treating toxic gases such as hydrogen sulfide (H2S). This study investigated the structural dynamics linked to the functional prediction of microbial communities in a full-scale biofilter installed near a sewage lift station. Sampling and analysis were conducted for 720 days. Illumina 16S rRNA sequencing was used to assess the taxonomic profile, followed by putative evaluation of functional genes. H2S removal efficiency reached 90% of the compound concentration at the inlet halfway up the filter bed height. Spatial variability had a greater effect on the microbial community. Studies focused on bacterial behavior and structure in biofiltration systems are still scarce, and only through further research can we fully understand the dynamics. Resumo: A eficiência dos biofiltros depende da comunidade microbiana, portanto é crucial conhecer a dinâmica estrutural/funcional e identificar os principais gêneros microbianos ligados ao tratamento de gases tóxicos, como o sulfeto de hidrogênio (H2S). Este trabalho investigou a dinâmica estrutural ligada à predição funcional das comunidades microbianas de um biofiltro em escala real instalado próximo a uma estação elevatória de esgoto. A amostragem e a análise foram conduzidas por 720 dias. O sequenciamento Illumina 16S rRNA foi usado para avaliar o perfil taxonômico, seguido pela avaliação putativa de genes funcionais. A eficiência de remoção de H2S atingiu 90% da concentração do composto na entrada já na metade da altura do leito filtrante. A variável espacial teve maio refeito sobre a comunidade microbiana. Estudos focados no comportamento e estrutura bacteriana em sistemas de biofiltração ainda são escassos, e somente com mais pesquisas poderemos entender a dinâmica comportamental

Sensitivity plots for WIMP direct detection using the annual modulation signature

Annual modulation due to the Earth's motion around the Sun is a well known signature of the expected WIMP signal induced in a solid state underground detector. In the present letter we discuss the prospects of this technique on statistical grounds, introducing annual-modulation sensitivity plots for the WIMP-nucleon scalar cross section for different materials and experimental conditions. The highest sensitivity to modulation is found in the WIMP mass interval 10 GeV< m_W < 130 GeV, the actual upper limit depending from the choice of the astrophysical parameters, while the lowest values of the explorable WIMP-nucleon elastic cross-sections fall in most cases within one order of magnitude of the sensitivities of present direct detection WIMP searches.Comment: 24 pages, ReVTeX, 9 figures, submitted to Astroparticle Physic

Search for an annual modulation of dark-matter signals with a germanium spectrometer at the Sierra Grande Laboratory

Data collected during three years with a germanium spectrometer at the Sierra Grande underground laboratory have been analyzed for distinctive features of annual modulation of the signal induced by WIMP dark matter candidates. The main motivation for this analysis was the recent suggestion by the DAMA/NaI Collaboration that a yearly modulation signal could not be rejected at the 90% confidence level when analyzing data obtained with a high-mass low-background scintillator detector. We performed two different analyses of the data: First, the statistical distribution of modulation-significance variables (expected from an experiment running under the conditions of Sierra Grande) was compared with the same variables obtained from the data. Second, the data were analyzed in energy bins as an independent check of the first result and to allow for the possibility of a crossover in the expected signal. In both cases no statistically significant deviation from the null result was found, which could support the hypothesis that the data contain a modulated component. A plot is also presented to enable the comparison of these results to those of the DAMA collaboration.Comment: New version accepted by Astroparticle Physics. Changes suggested by the referee about the theoretical prediction of rates are included. Conclusions remain unaffected. 14 pages, LaTeX, 7 figures. Uses epsfig macr

Breast tumor cell invasion and pro-invasive activity of cancer-associated fibroblasts co-targeted by novel urokinase-derived decapeptides

Among peritumoral cells, cancer-associated fibroblasts (CAFs) are major facilitators of tumor progression. This study describes the effects of two urokinase-derived, novel decapeptides, denoted as Pep 1 and its cyclic derivative Pep 2. In a mouse model of tumor dissemination, using HT1080 fibrosarcoma cells, Pep 2 reduced the number and size of lung metastases. Specific binding of fluoresceinated Pep 2 to HT1080 and telomerase immortalised fibroblasts (TIF) cell surfaces was enhanced by αv overexpression or abolished by excess vitronectin, anti-αv antibodies or silencing of ITGAV αv gene, identifying αv-integrin as the Pep 2 molecular target. In 3D-organotypic assays, peptide-exposed TIFs and primary CAFs from breast carcinoma patients both exhibited a markedly reduced pro-invasive ability of either HT1080 fibrosarcoma or MDA-MB-231 mammary carcinoma cells, respectively. Furthermore, TIFs, either exposed to Pep 2, or silenced for αv integrin, were impaired in their ability to chemoattract cancer cells and to contract collagen matrices, exhibiting reduced α-smooth muscle actin (α-SMA) levels. Finally, peptide exposure of αv-expressing primary CAFs led to the downregulation of α-SMA protein and to a dramatic reduction of their pro-invasive capability. In conclusion, the ability of the novel decapeptides to interfere with tumor cell invasion directly and through the down-modulation of CAF phenotype suggests their use as lead compounds for co-targeting anti-cancer strategies

Primary systemic treatment and concomitant low dose radiotherapy for breast cancer: final results of a prospective phase II study.

Abstract Background To evaluate the efficacy of preoperative low dose fractionated radiotherapy (LD-FRT) and chemotherapy in breast cancer. Materials and methods Patients with stage IIA–IIIA breast cancer, received LD-FRT (0.40 Gy bid, on day 1 and 2, for 6 cycles) to primary tumor volume and concurrent chemotherapy with non-pegylated liposomal anthracycline and docetaxel. Pathological response was assessed by Mandard Tumor Regression Grade (TRG). We evaluated the pathological major response rate (PMRR) as TRG1 and TRG2. The expected outcome was a PMRR of 60%. The accrual was determined by the single proportion powered analysis ( α = 0.05, power = 0.8). Results Twentyone patients were enrolled. No grade 2–4 acute skin and hematological toxicity was observed. TRG1 was obtained in 3 patients (14.3%), TRG2 in 4 patients (19%). The PMRR was 33.3%; it does not concur with the expected result, but is similar to that of chemotherapy alone. According to molecular subtype, 2/11 luminal A patients and 4/6 luminal B patients obtained a PMRR to preoperative treatment (35.3%); 1/4 basal like patients reported TRG1 (25%). Conclusions LD-FRT concomitant with primary systemic treatment has a good toxicity profile. The response rate is consistent with that of chemotherapy alone, and suggests different interactions between low dose radiotherapy and molecular subtypes. Additional investigations are planned

Experimental and simulation analysis of carrier lifetimes in GaAs/AlGaAs Avalanche Photo-Diodes

Extensive experimental characterization and TCAD simulation analysis have been used to study the dark current in Avalanche Photo-Diodes (APDs). The comparison between the temperature dependence of measurements and simulations points out that SRH generation/recombination is responsible for the observed dark current. After the extraction of the carrier lifetimes in the GaAs layers, they have been used to predict the APD collection efficiency of the photo-generated currents under realistic operation conditions and as a function of the photogeneration position inside the absorption layer