439 research outputs found

    Do Salamanders Limit the Abundance of Groundwater Invertebrates in Subterranean Habitats?

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    Several species of surface salamanders exploit underground environments; in Europe, one of the most common is the fire salamander (Salamandra salamandra). In this study, we investigated if fire salamander larvae occurring in groundwater habitats can affect the abundance of some cave-adapted species. We analyzed the data of abundance of three target taxa (genera Niphargus (Amphipoda; Niphargidae), Monolistra (Isopoda; Sphaeromatidae) and Dendrocoelum (Tricladida; Dedrocoelidae)) collected in 386 surveys performed on 117 sites (pools and distinct subterranean stream sectors), within 17 natural and 24 artificial subterranean habitats, between 2012 and 2019. Generalized linear mixed models were used to assess the relationship between target taxa abundance, fire salamander larvae occurrence, and environmental features. The presence of salamander larvae negatively affected the abundance of all the target taxa. Monolistra abundance was positively related with the distance from the cave entrance of the sites and by their surface. Our study revealed that surface salamanders may have a negative effect on the abundance of cave-adapted animals, and highlited the importance of further investigations on the diet and on the top-down effects of salamanders on the subterranean communities

    Modelling of an intersubband quantum confined Stark effect in Ge quantum wells for mid-infrared photonics

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    : In this work we theoretically investigate quantum confined Stark effect of intersubband transitions in asymmetric Ge/SiGe quantum wells for intensity modulation in the mid-infrared. Our calculations show that extinction ratios up to 1 dB and modulation speeds of several tens of GHz could be obtained in 100 µm long waveguides

    Stephen Jay Gould and Karl Popper on Science and Religion

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    This paper analyzes the thought on science and religion of two thinkers that share essentially the same position: Stephen Jay Gould and Karl Popper. We first make a comparison between those passages of their works where this similarity emerges more explicitly. We then recall some of the critiques that have been extended to Gould on this topic; they can be extended to Popper as well. Moreover, we highlight another critical issue—taken from evolutionary theory—that Gould’s theorization is not able to handle adequately from the theological standpoint. We finally place Gould’s proposal inside Barbour’s fourfold typology for the science-religion relationship, and we conclude by recommending further critical reflection on these interdisciplinary issues

    Impact of the inversion time on regional brain perfusion estimation with clinical arterial spin labeling protocols

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    Objective: Evaluating the impact of the Inversion Time (TI) on regional perfusion estimation in a pediatric cohort using Arterial Spin Labeling (ASL). Materials and methods: Pulsed ASL (PASL) was acquired at 3 T both at TI 1500 ms and 2020 ms from twelve MRI-negative patients (age range 9–17 years). A volume of interest (VOIs) and a voxel-wise approach were employed to evaluate subject-specific TI-dependent Cerebral Blood Flow (CBF) differences, and grey matter CBF Z-score differences. A visual evaluation was also performed. Results: CBF was higher for TI 1500 ms in the proximal territories of the arteries (PTAs) (e.g. insular cortex and basal ganglia — P < 0.01 and P < 0.05 from the VOI analysis, respectively), and for TI 2020 ms in the distal territories of the arteries (DTAs), including the watershed areas (e.g. posterior parietal and occipital cortex — P < 0.001 and P < 0.01 from the VOI analysis, respectively). Similar differences were also evident when analyzing patient-specific CBF Z-scores and at a visual inspection. Conclusions: TI influences ASL perfusion estimates with a region-dependent effect. The presence of intraluminal arterial signal in PTAs and the longer arterial transit time in the DTAs (including watershed areas) may account for the TI-dependent differences. Watershed areas exhibiting a lower perfusion signal at short TIs (~ 1500 ms) should not be misinterpreted as focal hypoperfused areas

    CAN METABOLIC SYNDROME AFFECT THE EFFICACY OUTCOMES OF COMBINATION THERAPY WITH DAILY TADALAFIL 5MG PLUS TAMSULOSIN 0.4MG IN MEN WITH LUTS AND ED?

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    INTRODUCTION AND OBJECTIVE: Metabolic Syndrome (METS) has a high prevalence (26.5%–55.6%) in men with LUTS and erectile dysfunction (ED). Daily tadalafil 5mg intake is currently recognized as an effective pharmacological treatment for male LUTS, alone or in combination with alpha-lithics such as tamsulosin 0,4mg, ensuring a greater LUTS relieve. Aim of this study is to assess if METS could affect the efficacy of combination therapy with daily tadalafil 5mg plus tamsulosin 0,4mg in men with LUTS and ED. METHODS: Across 12 months, fifty consecutive patients aged &gt;40 to 80 years, with moderate to severe LUTS (IPSS &gt;7) and mild to severe ED (IIEF-5 &lt;22) were enrolled and treated with the previous combination therapy for 12 weeks. The assessment of patients included age, body mass index (BMI), METS features - waist circumference (WC), blood pressure, clinical laboratory parameters- digital rectal examination, IPSS, OABq, uroflowmetry and postvoid residual (PVR) volume, IIEF-5. METS was defined according to NCEP ATP III. Differences were calculated by unpaired sample t-test at baseline and 12 weeks. The analysis of variance (ANOVA) was used for between-group differences. RESULTS: Among 50 patients enrolled, 31 (62.0%) had METS. Mean age was similar with 65.5 years (9.1) in patients without METS and 67.1 years (7.2) in METS patients, p=0.133. Baseline IPSS, OAB-q and IPSS QoL were significantly higher in patients with METS (p&lt;0.05), while IIEF was higher in patients without METS (p=0.039) at baseline (Table1). After 3 months of combination therapy, IIEF, total IPSS and subscores, OAB-q and Qmax significantly improved in both groups. DeltaIPSS, deltaQMax and deltaIIEF were similar between groups (p&gt;0.05). However, total IPSS, IPSS QoL, IPSS Voiding and IPSS Storage were significantly better at the end of the trial in men without METS. Conversely, 12wks IIEF was similar in patients with or without METS (16.3 vs 17.7 p=0.238) (Table2). CONCLUSIONS: Tadalafil plus tamsulosin combi therapy represents an effective LUTS treatment in male, independently from METS. Despite a similar improvement of LUTS (delta), patients without METS obtained a significantly better LUTS relieve. Interestingly, the efficacy in ED was greater in men with METS and, at the end of trial, IEEF-5 scores were similar in the two groups

    Ge and Si Microcrystal Photodetectors with Enhanced Infrared Responsivity

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    Ge and Si micro-crystals, grown on Si patterned substrates, can be used as absorbing elements for photodetection in the near-infrared. In such microstructures, light confinement effects due to crystal facet, enhance light absorption in the near-infrared as compared to conventional epitaxial layers. Devices based on single micro-crystals and on micro-crystals arrays have been fabricated and characterized. The photocurrent of Si photodetectors based on single micro-crystals have been measured in linear and avalanche regime, demonstrating a state-of-the-gain of ≈10 4. Ge-on-Si photodetectors based on micro-crystal arrays, fabricated using graphene as top contact, have also been fabricated, showing a responsivity in the 1500-1800 nm exceeding that of conventional planar devices

    Urogenital Abnormalities in Adenosine Deaminase Deficiency

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    BACKGROUND: Improved survival in ADA-SCID patients is revealing new aspects of the systemic disorder. Although increasing numbers of reports describe the systemic manifestations of adenosine deaminase deficiency, currently there are no studies in the literature evaluating genital development and pubertal progress in these patients. METHODS: We collected retrospective data on urogenital system and pubertal development of 86 ADA-SCID patients followed in the period 2000-2017 at the Great Ormond Street Hospital (UK) and 5 centers in Italy. In particular, we recorded clinical history and visits, and routine blood tests and ultrasound scans were performed as part of patients' follow-up. RESULTS AND DISCUSSION: We found a higher frequency of congenital and acquired undescended testes compared with healthy children (congenital, 22% in our sample, 0.5-4% described in healthy children; acquired, 16% in our sample, 1-3% in healthy children), mostly requiring orchidopexy. No urogenital abnormalities were noted in females. Spontaneous pubertal development occurred in the majority of female and male patients with a few cases of precocious or delayed puberty; no patient presented high FSH values. Neither ADA-SCID nor treatment performed (PEG-ADA, BMT, or GT) affected pubertal development or gonadic function. CONCLUSION: In summary, this report describes a high prevalence of cryptorchidism in a cohort of male ADA-SCID patients which could represent an additional systemic manifestation of ADA-SCID. Considering the impact urogenital and pubertal abnormalities can have on patients' quality of life, we feel it is essential to include urogenital evaluation in ADA-SCID patients to detect any abnormalities, initiate early treatment, and prevent long-term complications
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