Neutron spectrometer for fast nuclear reactors

In this paper we describe the development and first tests of a neutron spectrometer designed for high flux environments, such as the ones found in fast nuclear reactors. The spectrometer is based on the conversion of neutrons impinging on $^6$Li into $\alpha$ and $t$ whose total energy comprises the initial neutron energy and the reaction $Q$-value. The $^6$LiF layer is sandwiched between two CVD diamond detectors, which measure the two reaction products in coincidence. The spectrometer was calibrated at two neutron energies in well known thermal and 3 MeV neutron fluxes. The measured neutron detection efficiency varies from 4.2$\times 10^{-4}$ to 3.5$\times 10^{-8}$ for thermal and 3 MeV neutrons, respectively. These values are in agreement with Geant4 simulations and close to simple estimates based on the knowledge of the $^6$Li(n,$\alpha$)$t$ cross section. The energy resolution of the spectrometer was found to be better than 100 keV when using 5 m cables between the detector and the preamplifiers.Comment: submitted to NI

Platelet-Rich Plasma combined with a sterile 3D polylactic acid scaffold for postoperative management of complete hoof wall resection for keratoma in four horses.

Keratoma is a non-malignant horse tumour that grows in the space between the horn of the hoof and the distal phalanx. Keratoma causes lameness in the horse, and surgical excision is the treatment of choice. Four horses underwent removal of a keratoma by complete hoof wall resection. The remaining wound was treated with Platelet-Rich Plasma (PRP) combined with a sterile 3D polylactic acid scaffold. The PRP was applied at 3, 6, 9, 12, 15 and 18 days postoperatively. The surgical site was cleaned with gauzes and swabs soaked in Ringer’s lactate solution before applying PRP and the foot bandage. Healthy granulation tissue developed at 6-21 days postoperatively. The hoof wall defect was completely filled with new hoof wall within 6-8 months after surgery. All horses returned to their previous exercise level and no recurrence of lameness was reported by the owner

Catestatin Increases the Expression of Anti-Apoptotic and Pro-Angiogenetic Factors in the Post-Ischemic Hypertrophied Heart of SHR.

BACKGROUND:In the presence of comorbidities the effectiveness of many cardioprotective strategies is blunted. The goal of this study was to assess in a hypertensive rat model if the early reperfusion with anti-hypertensive and pro-angiogenic Chromogranin A-derived peptide, Catestatin (CST:hCgA352-372; CST-Post), protects the heart via Reperfusion-Injury-Salvage-Kinases (RISK)-pathway activation, limiting infarct-size and apoptosis, and promoting angiogenetic factors (e.g., hypoxia inducible factor, HIF-1α, and endothelial nitric oxide synthase, eNOS, expression). METHODS AND RESULTS:The effects of CST-Post on infarct-size, apoptosis and pro-angiogenetic factors were studied in isolated hearts of spontaneously hypertensive rats (SHR), which underwent the following protocols: (a) 30-min ischemia and 120-min reperfusion (I/R); (b) 30-min ischemia and 20-min reperfusion (I/R-short), both with and without CST-Post (75 nM for 20-min at the beginning of reperfusion). In unprotected Wistar-Kyoto hearts, used as normal counterpart, infarct-size resulted smaller than in SHR. CST-Post reduced significantly infarct-size and improved post-ischemic cardiac function in both strains. After 20-min reperfusion, CST-Post induced S-nitrosylation of calcium channels and phosphorylation of RISK-pathway in WKY and SHR hearts. Yet specific inhibitors of the RISK pathway blocked the CST-Post protective effects against infarct in the 120-min reperfusion groups. Moreover, apoptosis (evaluated by TUNEL, ARC and cleaved caspase) was reduced by CST-Post. Importantly, CST-Post increased expression of pro-angiogenetic factors (i.e., HIF-1α and eNOS expression) after two-hour reperfusion. CONCLUSIONS:CST-Post limits reperfusion damages and reverses the hypertension-induced increase of I/R susceptibility. Moreover, CST-Post triggers antiapoptotic and pro-angiogenetic factors suggesting that CST-Post can be used as an anti-maladaptive remodeling treatment

Network Physiology reveals relations between network topology and physiological function

The human organism is an integrated network where complex physiologic systems, each with its own regulatory mechanisms, continuously interact, and where failure of one system can trigger a breakdown of the entire network. Identifying and quantifying dynamical networks of diverse systems with different types of interactions is a challenge. Here, we develop a framework to probe interactions among diverse systems, and we identify a physiologic network. We find that each physiologic state is characterized by a specific network structure, demonstrating a robust interplay between network topology and function. Across physiologic states the network undergoes topological transitions associated with fast reorganization of physiologic interactions on time scales of a few minutes, indicating high network flexibility in response to perturbations. The proposed system-wide integrative approach may facilitate the development of a new field, Network Physiology.Comment: 12 pages, 9 figure

Sarcoptic mange in wild ruminants in Spain: solving the epidemiological enigma using microsatellite markers

Background: In Spain, sarcoptic mange was first described in native wildlife in 1987 in Cazorla Natural Park, causing the death of nearly 95% of the local native population of Iberian ibex (Capra pyrenaica). Since then, additional outbreaks have been identified in several populations of ibex and other wild ungulate species throughout the country. Although the first epizootic outbreak in wildlife was attributed to the introduction of an infected herd of domestic goats, the origin and the cause of its persistence remain unclear. The main aims of this study are to understand (i) the number of Sarcoptes scabiei “strains” circulating in wild ruminant populations in Spain, and (ii) the molecular epidemiological relationships between S. scabiei and its hosts. Methods: Ten Sarcoptes microsatellite markers were used to characterize the genetic structure of 266 mites obtained from skin scrapings of 121 mangy wild ruminants between 2011 and 2019 from 11 areas in Spain. Results: Seventy-three different alleles and 37 private alleles were detected. The results of this study show the existence of three genetic strains of S. scabiei in the wild ruminant populations investigated. While two genetic clusters of S. scabiei were host- and geography-related, one cluster included multi-host mites deriving from geographically distant populations. Conclusions: The molecular epidemiological study of S. scabiei in wild ruminants in Spain indicates that the spreading and persistence of the parasite may be conditioned by host species community composition and the permissiveness of each host population/community to the circulation of individual “strains,” among other factors. Wildlife–livestock interactions and the role of human-driven introduction or trade of wild and domestic animals should be better investigated to prevent further spread of sarcoptic mange in as yet unaffected natural areas of the Iberian Peninsula