169 research outputs found

    Continental degassing of helium in an active tectonic setting (northern Italy): the role of seismicity

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    In order to investigate the variability of helium degassing in continental regions, its release from rocks and emission into the atmosphere, here we studied the degassing of volatiles in a seismically active region of northern Italy (MwMAX = 6) at the Nirano-Regnano mud volcanic system. The emitted gases in the study area are CH4–dominated and it is the carrier for helium (He) transfer through the crust. Carbon and He isotopes unequivocally indicate that crustal-derived fluids dominate these systems. An high-resolution 3-dimensional reconstruction of the gas reservoirs feeding the observed gas emissions at the surface permits to estimate the amount of He stored in the natural reservoirs. Our study demonstrated that the in-situ production of 4He in the crust and a long-lasting diffusion through the crust are not the main processes that rule the He degassing in the region. Furthermore, we demonstrated that micro-fracturation due to the field of stress that generates the local seismicity increases the release of He from the rocks and can sustain the excess of He in the natural reservoirs respect to the steady-state diffusive degassing. These results prove that (1) the transport of volatiles through the crust can be episodic as function of rock deformation and seismicity and (2) He can be used to highlight changes in the stress field and related earthquakes

    Novel composites for wing and fuselage applications

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    Probabilistic predictions based on the IPACS code are presented for the material and structural response of unnotched and notched, IM6/3501-6 Gr/Ep laminates. Comparisons of predicted and measured modulus and strength distributions are given for unnotched unidirectional, cross-ply and quasi-isotropic laminates. The predicted modulus distributions were found to correlate well with the test results for all three unnotched laminates. Correlations of strength distributions for the unnotched laminates are judged good for the unidirectional laminate and fair for the cross-ply laminate, whereas the strength correlation for the quasi-isotropic laminate is judged poor because IPACS did not have a progressive failure capability at the time this work was performed. The report also presents probabilistic and structural reliability analysis predictions for the strain concentration factor (SCF) for an open-hole, quasi-isotropic laminate subjected to longitudinal tension. A special procedure was developed to adapt IPACS for the structural reliability analysis. The reliability results show the importance of identifying the most significant random variables upon which the SCF depends, and of having accurate scatter values for these variables

    A slow lopsided bar in the interacting dwarf galaxy IC 3167

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    We present surface photometry and stellar kinematics of IC 3167, a dwarf galaxy hosting a lopsided weak bar and infalling into the Virgo cluster. We measured the bar radius and strength from broad-band imaging and bar pattern speed by applying the Tremaine-Weinberg method to stellar-absorption integral-field spectroscopy. We derived the ratio of the corotation radius to bar radius (R = 1.7 + 0.5 - 0.3) from stellar kinematics and bar pattern speed. The probability that the bar is rotating slowly is more than twice as likely as that the bar is fast. This allows us to infer that the formation of this bar was triggered by the ongoing interaction rather than to internal processes.Comment: Accepted for pubblication in MNRAS Letter

    Developing Future Biologists: Developmental Biology for Undergraduates from Underserved Communities

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    Developing Future Biologists (DFB) is an inclusive, trainee-run organization that strives to excite and engage the next generation of biologists, regardless of race, gender or socioeconomic status, in the field of developmental biology. DFB offers a week-long course consisting of active lectures, hands-on laboratory sessions, and professional development opportunities through interactions with scientists from a variety of backgrounds and careers. A major goal of DFB is to propel undergraduate students from underserved communities to pursue biomedical research opportunities and advanced degrees in science. To achieve this goal, we provide DFB participants with continuing access to a diverse network of scientists that students can utilize to secure opportunities and foster success throughout multiple stages of their research careers. Here, we describe the flourishing DFB program at the University of Michigan to encourage other institutions to create their own DFB programs

    Hormone-dependent control of developmental timing through regulation of chromatin accessibility

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    Specification of tissue identity during development requires precise coordination of gene expression in both space and time. Spatially, master regulatory transcription factors are required to control tissue-specific gene expression programs. However, the mechanisms controlling how tissue-specific gene expression changes over time are less well understood. Here, we show that hormone-induced transcription factors control temporal gene expression by regulating the accessibility of DNA regulatory elements. Using the Drosophila wing, we demonstrate that temporal changes in gene expression are accompanied by genome-wide changes in chromatin accessibility at temporal-specific enhancers. We also uncover a temporal cascade of transcription factors following a pulse of the steroid hormone ecdysone such that different times in wing development can be defined by distinct combinations of hormone-induced transcription factors. Finally, we show that the ecdysone-induced transcription factor E93 controls temporal identity by directly regulating chromatin accessibility across the genome. Notably, we found that E93 controls enhancer activity through three different modalities, including promoting accessibility of late-acting enhancers and decreasing accessibility of early-acting enhancers. Together, this work supports a model in which an extrinsic signal triggers an intrinsic transcription factor cascade that drives development forward in time through regulation of chromatin accessibility

    A slow bar in the lenticular barred galaxy NGC 4277

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    Aims. We characterised the properties of the bar hosted in lenticular galaxy NGC 4277, which is located behind the Virgo cluster. Methods. We measured the bar length and strength from the surface photometry obtained from the broad-band imaging of the Sloan Digital Sky Survey and we derived the bar pattern speed from the stellar kinematics obtained from the integral-field spectroscopy performed with the Multi Unit Spectroscopic Explorer at the Very Large Telescope. We also estimated the co-rotation radius from the circular velocity, which we constrained by correcting the stellar streaming motions for asymmetric drift, and we finally derived the bar rotation rate. Results. We found that NGC 4277 hosts a short (Rbar = 3.2 +0.9 −0.6 kpc), weak (S bar = 0.21 ± 0.02), and slow (R = 1.8 +0.5 −0.3) bar and its pattern speed (Ωbar = 24.7 ± 3.4 km s−1 kpc−1) is amongst the best-constrained ones ever obtained with the Tremaine-Weinberg (TW) method with relative statistical errors of ∼ 0.2. Conclusions. NGC 4277 is the first clear-cut case of a galaxy hosting a slow stellar bar (R > 1.4 at more than a 1σ confidence level) measured with the model-independent TW method. A possible interaction with the neighbour galaxy NGC 4273 could have triggered the formation of such a slow bar and/or the bar could be slowed down due to the dynamical friction with a significant amount of dark matter within the bar region

    BRCA1/2 Molecular Assay for Ovarian Cancer Patients: A Survey through Italian Departments of Oncology and Molecular and Genomic Diagnostic Laboratories

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    In Italy, 5200 new ovarian cancers were diagnosed in 2018, highlighting an increasing need to test women for BRCA1/2. The number of labs offering this test is continuously increasing. The aim of this study was to show the results coming from the intersociety survey coordinated by four different Clinical and Laboratory Italian Scientific Societies (AIOM, SIAPEC-IAP, SIBIOC, and SIGU). A multidisciplinary team belonging to the four scientific societies drew up two different questionnaires: One was targeted toward all Italian Departments of Medical Oncology, and the second toward laboratories of clinical molecular biology. This survey was implemented from September 2017 to March 2018. Seventy-seven out of 305 (25%) Departments of Medical Oncology filled our survey form. Indeed, 59 molecular laboratories were invited. A total of 41 laboratories (70%) filled in the questionnaire. From 2014 to 2017, 16 new molecular laboratories were activated. A total of 12,559 tests were performed in the year 2016, with a mean of 339 tests and a median of 254 tests per laboratory, showing a glimpse of an extreme low number of tests performed per year by some laboratories. In terms of the type and number of professionals involved in the pre- and post-test counseling, results among the onco-genetic team were heterogeneous. Our data show that the number of laboratories providing BRCA1/2 germline assays is significantly increased with further implementation of the somatic test coming soon. The harmonization of the complete laboratory diagnostic path should be encouraged, particularly in order to reduce the gap between laboratories with high and low throughput

    IoT monitoring of water consumption for irrigation systems using SEMMA methodology

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    The efficient use of water is an issue that has captured the attention of scientists, technicians, and the community at large. The sustainability of water resources has been threatened by the current imbalance between water supply and demand. Intelligent consumption of water would contribute to the balance and reduce the waste in applications such as the agriculture. This paper shows the design of a water consumption monitoring system based on the Internet of Things (IoT). With the implementation of this system could be known in real time the consumption of water in a crop. In addition, the user of the system may take corrective actions that optimize their water consumption; this is achieved by applying the SEMMA methodology to evaluate the data obtained by the system using two cluster algorithms, Simple K-means and GenClus++. With the application of SEMMA it was possible to determine periods of water consumption that were considered as waste in the irrigation of crops, applying data analysis with both algorithms
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