636 research outputs found

    Preliminary bioassays on the susceptibility of stone fruits rootstocks to Capnodis tenebrionis (L.).

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    Capnodis tenebrionis (L.) (Coleoptera: Buprestidae), the so called Mediterranean flat-headed root-borer, is an economically important phytophagous pest species mainly on stone fruit trees (apricot, plum, cherry, peach and nectarine). Chemicals and Entomopathogenic nematodes are used for the control of adults and neonate larvae, respectively. Further control means are under investigations in order to have more options within Integrated Pest Control strategies. This study is aimed at investigating the susceptibility of rootstocks to the larvae of C. tenebrionis. Two bioassays were carried out during 2016 and 2017. A first bioassay was based on the evaluation of a potential antixenosis action expressed by neonate larvae infesting twigs of rootstocks (Marianna 26, Barrier, Adesoto, Mylaboran 29C, GF677, Garnem, Cab 6P, Max Ma60 and Colt). This bioassay allowed to process a high number of different rootstocks in a short time. It has a preliminary value. The second bioassay assessed the antibiosis influence of the rootstocks through the breeding of larvae (since the neonate ones) on artificial diets containing bark flour of Adesoto, Cab 6P, Colt, Garnem, GF677, Max Ma60, Montclar and 29C rootstock. The first bioassay showed that Colt, Mylaboran 29C and GF677 were the most susceptible rootstocks to larval infestation of C. tenebrionis and Max Ma60 was less favorable to the pest. Concerning the effects of the diet, larvae reared on a diet containing Montclar, Cab 6P and GF 677 bark flour had a mean daily increase of their weight higher that those reared on cortex tissues of other genotypes whereas Garnem and Colt had a lower increase

    Syn-exhumation coupling of oceanic and continental units along the western edge of the alpine corsica: A review

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    The Alpine Corsica represents a segment of the Alpine collisional belt. In its western edge, it is characterized by the close association of continental units deformed under high-pressure metamorphic conditions (Lower Units) and oceanic units showing a metamorphism ranging from high-pressure (Schistes Lus-trés Complex) to very low-grade conditions (Upper Units). This paper provides a complete review of the relationships between the continental and oceanic units in selected five areas where the stratigraphic features, deformation history, metamorphic P-T path and tectonic setting are available for each unit. The collected data indicate that the oceanic units occur not only at the top of the continental ones, as generally proposed in the literature, but also intercalated within them. Such relationships were achieved at shallow structural level during the late stage of exhumation, when the continental units were tectonically coupled with the oceanic units which were dragged as slices from the orogenic wedge. The coupling probably occurred immediately before the transition from syn-to post-orogenic geodynamic regime that affected the whole Alpine-Apennine collisional system in the early Oligocene. After the coupling, the stack of oceanic and continental units experienced a further exhumation-related deformation before their final exposure at the surface

    Polaronic state and nanometer-scale phase separation in colossal magnetoresistive manganites

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    High resolution topographic images obtained by scanning tunneling microscope in the insulating state of Pr0.68Pb0.32MnO3 single crystals showed regular stripe-like or zigzag patterns on a width scale of 0.4 - 0.5 nm confirming a high temperature polaronic state. Spectroscopic studies revealed inhomogeneous maps of zero-bias conductance with small patches of metallic clusters on length scale of 2 - 3 nm only within a narrow temperature range close to the metal-insulator transition. The results give a direct observation of polarons in the insulating state, phase separation of nanometer-scale metallic clusters in the paramagnetic metallic state, and a homogeneous ferromagnetic state

    Gut microbiota composition and frailty in elderly patients with Chronic Kidney Disease

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    Background Frailty is common in older patients affected by chronic kidney disease (CKD). Since gut microbiota (gMB) may contribute to frailty, we explored possible associations between gMB and frailty in CKD. Methods We studied 64 CKD patients (stage 3b-4), categorized as frail (F, 38) and not frail (NF, 26) according to Fried criteria, and 15 controls (C), all older than 65 years. In CKD we assessed serum C-reactive protein, blood neutrophil/lymphocyte ratio, Malnutrition-inflammation Score (MIS); gMB was studied by denaturing gel gradient electrophoresis (DGGE), high-throughput sequencing (16S r-RNA gene), and quantitative real-time PCR (RT-PCR). Results No differences in alpha diversity between CKD and C and between F and NF patients emerged, but high-throughput sequencing showed significantly higher abundance of potentially noxious bacteria (Citrobacter, Coprobacillus, etc) and lower abundance of saccharolytic and butyrate-producing bacteria (Prevotella spp., Faecalibacterium prausnitzii, Roseburia spp.), in CKD respect to C. Mogibacteriaceae family and Oscillospira genus abundance was positively related to inflammatory indices in the whole CKD cohort, while that of Akkermansia, Ruminococcus and Eubacterium genera was negatively related. Compared with NF, in F there was a higher abundance of some bacteria (Mogibacteriacee, Coriobacteriacee, Eggerthella, etc), many of which have been described as more abundant in other diseases. Conclusions These results suggest that inflammation and frailty could be associated to gMB modifications in CKD

    Experimental evidence for the role of cantori as barriers in a quantum system

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    We investigate the effect of cantori on momentum diffusion in a quantum system. Ultracold caesium atoms are subjected to a specifically designed periodically pulsed standing wave. A cantorus separates two chaotic regions of the classical phase space. Diffusion through the cantorus is classically predicted. Quantum diffusion is only significant when the classical phase-space area escaping through the cantorus per period greatly exceeds Planck's constant. Experimental data and a quantum analysis confirm that the cantori act as barriers.Comment: 19 pages including 9 figures, Accepted for publication in Physical Review E in March 199

    Mixed brittle and viscous strain localisation in pelagic sediments seaward of the Hikurangi margin, New Zealand

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    Calcareous‐pelagic input sediments are present at several subduction zones and deform differently to their siliciclastic counterparts. We investigate deformation in calcareous‐pelagic sediments drilled ~20 km seaward of the Hikurangi megathrust toe at Site U1520 during IODP Expeditions 372 and 375. Clusters of normal faults and subhorizontal stylolites in the sediments indicate both brittle faulting and viscous pressure solution operated at 150°C where frictional (possibly seismic) slip likely predominates. Plain Language Summary The type of sediments entering subduction zones will influence the way the plates in the subduction zone slide past one another. We looked at limestones in sediments drilled before they reach the subduction zone and found that because of the pressure they are under, they begin to crack and dissolve at very shallow depths. Most of the dissolution happens on thin layers where it concentrates clay by removing other, more soluble minerals. We compare how much vertical shortening we see in the sediments to a computer model. The model overestimates vertical shortening over the history of the sediment unless either high pressure fluids reduce the pressure felt by the sediments, or dissolution is governed by the largest sediment grains rather than their average size. Dissolving and cracking make the sediments weaker by concentrating soft materials such as clay. When these sediments enter the subduction zone, the two plates might slip past one another more easily on these weak regions, possibly during slow slip events

    Is lung ultrasound imaging a worthwhile procedure for severe acute respiratory syndrome coronavirus 2 pneumonia detection?

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    Objectives: We compared 2 imaging modalities in patients suspected of having coronavirus disease 2019 (COVID-19) pneumonia. Blinded to the results of real-time reverse transcriptase polymerase chain reaction (rRT-PCR) testing, lung ultrasound (LUS) examinations and chest computed tomography (CT) were performed, and the specific characteristics of these imaging studies were assessed. Methods: From March 15, 2020, to April 15, 2020, 63 consecutive patients were enrolled in this prospective pilot study. All patients underwent hematochemical tests, LUS examinations, chest CT, and confirmatory rRT-PCR. The diagnostic performance of LUS and chest CT was calculated with rRT-PCR as a reference. The interobserver agreement of radiologists and ultrasound examiners was calculated. Ultrasound and CT features were compared to assess the sensitivity, specificity, positive predictive value, and negative predictive value. Positive and negative likelihood ratios measured the diagnostic accuracy. Results: Nineteen (30%) patients were COVID-19 negative, and 44 (70%) were positive. No differences in demographics and clinical data at presentation were observed among positive and negative patients. Interobserver agreement for CT had a κ value of 0.877, whereas for LUS, it was 0.714. The sensitivity, specificity, positive predictive value, and negative predictive value of chest CT for COVID-19 pneumonia were 93%, 90%, 85%, and 95%, respectively; whereas for LUS, they were 68%, 79%, 88%, and 52%. On receiver operating characteristic curves, area under the curve values were 0.834 (95% confidence interval, 0.711–0.958) and 0.745 (95% confidence interval, 0.606–0.884) for chest CT and LUS. Conclusions: Lung ultrasound had good reliability compared to chest CT. Therefore, our results indicate that LUS may be used to assess patients suspected of having COVID-19 pneumonia

    Long-term evaluation of coronary artery calcifications in kidney transplanted patients : a follow up of 5 years

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    Coronary artery calcifications(CACs), are related to the increased cardiovascular mortality during kidney transplantation(KTx). Using coronary-CT performed at 1 month(T0) and 5 years(T5) after KTx we evaluated: (1) the prevalence of CACs; (2) the clinical and biochemical factors related to CACs; 3) the factors implicated with CACs progression. We evaluated 67-pts selected from the 103-pts transplanted in our unit between 2007 and 2008. Clinical and biochemical parameters were recorded at the time of pre-KTx evaluation and for five years after KTx. Coronary-CT for the Agatson score (AS) evaluation was performed at T0 and at T5, and CACs progression was determined. At baseline AS was 45 [0-233]. At T5 AS was 119 [1-413]. At T0, 69% of patients had CACs. Age and dialytic vintage were the main independent variables related to CACs. At T5, CACs were present in 76% of patients. Age was the only independent factor in determining CACs. A progression of CACs was observed in 74% of patients. They were older, had higher CACs-T0 and higher SBP throughout the 5-years. The presence of CACs at T0 and age were the only independent factors in determining the CACs-progression. CACs-T0 had the best discriminative power for CACs progression. CACs prevalence is quite high in KTx patients; Age is strictly related to CACs; Age and the presence of CACs at baseline were the two major factors associated with the progression of CACs during the five years of follow up. CACs-T0 had the best discriminative power for progression of CACs
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