The CYGNO experiment aims to build a large (\(\mathcal{O}(10)\) m\(^3\)) directional detector for rare event searches, such as nuclear recoils (NRs) induced by dark matter (DM), such as weakly ...interactive massive particles (WIMPs). The detector concept comprises a time projection chamber (TPC), filled with a He:CF\(_4\) 60/40 scintillating gas mixture at room temperature and atmospheric pressure, equipped with an amplification stage made of a stack of three gas electron multipliers (GEMs) which are coupled to an optical readout. The latter consists in scientific CMOS (sCMOS) cameras and photomultipliers tubes (PMTs). The maximisation of the light yield of the amplification stage plays a major role in the determination of the energy threshold of the experiment. In this paper, we simulate the effect of the addition of a strong electric field below the last GEM plane on the GEM field structure and we experimentally test it by means of a 10\(\times\)10 cm\(^2\) readout area prototype. The experimental measurements analyse stacks of different GEMs and helium concentrations in the gas mixture combined with this extra electric field, studying their performances in terms of light yield, energy resolution and intrinsic diffusion. It is found that the use of this additional electric field permits large light yield increases without degrading intrinsic characteristics of the amplification stage with respect to the regular use of GEMs.
SHiP (Search for Hidden Particles) is a beam dump experiment proposed at the CERN SPS aiming at the observation of long lived particles very weakly coupled with ordinary matter mostly produced in the ...decay of charmed hadrons. The beam dump facility of SHiP is also a copious factory of neutrinos of all three kinds and therefore a dedicated neutrino detector is foreseen in the SHiP apparatus. The neutrino detector exploits the Emulsion Cloud Chamber technique with a modular structure, alternating walls of target units and planes of electronic detectors providing the time stamp to the event. GEM detectors are one of the possible choices for this task. This paper reports the results of the first exposure to a muon beam at CERN of a new hybrid chamber, obtained by coupling a GEM chamber and an emulsion detector. Thanks to the micrometric accuracy of the emulsion detector, the position resolution of the GEM chamber as a function of the particle inclination was evaluated in two configurations, with and without the magnetic field
The performance and long term stability of an optically readout Time Projection Chamber with an electron amplification structure based on three Gas Electron Multipliers was studied. He/CF\(_4\) based ...gas mixtures were used in two different proportions (60/40 and 70/30) in a CYGNO prototype with 7 litres sensitive volume. With electrical configurations providing very similar electron gains, an almost full detection efficiency in the whole detector volume was found with both mixtures, while a light yield about 20\% larger for the 60/40 was found. The electrostatic stability was tested by monitoring voltages and currents during 25 days. The detector worked in very stable and safe condition for the whole period. In the presence of less CF\(_4\), a larger probability of unstable events was clearly detected.
Optical readout of Gas Electron Multipliers (GEM) provides very interesting performances and has been proposed for different applications in particle physics. In particular, thanks to its good ...efficiency in the keV energy range, it is being developed for low-energy and rare event studies, such as Dark Matter search. So far, the optical approach exploits the light produced during the avalanche processes in GEM channels. Further luminescence in the gas can be induced by electrons accelerated by a suitable electric field. The CYGNO collaboration studied this process with a combined use of a triple-GEM structure and a grid in an He/CF\(_4\) (60/40) gas mixture at atmospheric pressure. Results reported in this paper allow to conclude that with an electric field of about 11~kV/cm a photon production mean free path of about 1.0~cm was found.
The aim of the CYGNO project is the construction and operation of a 1~m\(^3\) gas TPC for directional dark matter searches and coherent neutrino scattering measurements, as a prototype toward the ...100-1000~m\(^3\) (0.15-1.5 tons) CYGNUS network of underground experiments. In such a TPC, electrons produced by dark-matter- or neutrino-induced nuclear recoils will drift toward and will be multiplied by a three-layer GEM structure, and the light produced in the avalanche processes will be readout by a sCMOS camera, providing a 2D image of the event with a resolution of a few hundred micrometers. Photomultipliers will also provide a simultaneous fast readout of the time profile of the light production, giving information about the third coordinate and hence allowing a 3D reconstruction of the event, from which the direction of the nuclear recoil and consequently the direction of the incoming particle can be inferred. Such a detailed reconstruction of the event topology will also allow a pure and efficient signal to background discrimination. These two features are the key to reach and overcome the solar neutrino background that will ultimately limit non-directional dark matter searches.
Highlights • First time demonstrating that CD47 blockade has anti-tumor effects against HCC. • In vitro CD47 blockade results in increase in phagocytosis of HCC cells. • In vivo CD47 blockade ...inhibits HCC tumor growth in hetero/orthotopic models. • CD47mAb400 is clearly more efficacious than widely-investigated B6H12 antibody.
Purpose
Primary (PVHs) and incisional (IHs) ventral hernias represent a common indication for surgery. Nevertheless, most of the papers presented in literature analyze both types of defect together, ...thus potentially introducing a bias in the results of interpretation. The purpose of this systematic review and meta-analysis is to highlight the differences between these two entities.
Methods
Methods MEDLINE, Scopus, and Web of Science databases were reviewed to identify studies evaluating the outcomes of both open and laparoscopic repair with mesh of PVHs vs IHs. Search was restricted to English language literature. Risk of bias was assessed with MINORS score. Primary outcome was recurrence, and secondary outcomes were baseline characteristics and intraoperative and postoperative data. Fixed effects model was used unless significant heterogeneity, assessed with the Higgins
I
square (
I
2
), was encountered.
Results
The search resulted in 783 hits, after screening; 11 retrospective trials were selected including 38,727 patients. Mean MINORS of included trials was 15.2 (range 5–21). The estimated pooled proportion difference for recurrence was − 0.09 (− 0.11; − 0.07) between the two groups in favor of the PVH group. On metanalysis, PVHs were smaller in area and diameters, affected younger and less comorbid patients, and were more frequently singular; the operative time and length of stay was quicker. Other complications did not differ significantly.
Conclusion
Our paper supports the hypothesis that PVH and IH are different conditions with the latter being more challenging to treat. Accordingly, EHS classifications should be adopted systematically as well as pooling data analysis should be no longer performed in clinical trials.
There is accumulating evidence that delivery of bone marrow cells to sites of ischemia by direct local injection or mobilization into the blood can stimulate angiogenesis. This has stimulated ...tremendous interest in the translational potential of angiogenic cell population(s) in the bone marrow to mediate therapeutic angiogenesis. However, the mechanisms by which these cells stimulate angiogenesis are unclear. Herein, we show that the inflammatory subset of monocytes is selectively mobilized into blood after surgical induction of hindlimb ischemia in mice and is selectively recruited to ischemic muscle. Adoptive-transfer studies show that delivery of a small number of inflammatory monocytes early (within 48 h) of induction of ischemia results in a marked increase in the local production of MCP-1, which in turn, is associated with a secondary, more robust wave of monocyte recruitment. Studies of mice genetically deficient in MCP-1 or CCR2 indicate that although not required for the early recruitment of monocytes, the secondary wave of monocyte recruitment and subsequent stimulation of angiogenesis are dependent on CCR2 signaling. Collectively, these data suggest a novel role for MCP-1 in the inflammatory, angiogenic response to ischemia.
Purpose
To assess the incidence of incisional hernia (IH) across various type of incisions in colorectal surgery (CS) creating a map of evidence to define research trends, gaps and areas of future ...interest.
Methods
Systematic review of PubMed and Scopus from 2010 onwards. Studies included both open (OS) and laparoscopic (LS). The primary outcome was incidence of IH 12 months after index procedure, secondary outcomes were the study features and their influence on reported proportion of IH. Random effects models were used to calculate pooled proportions. Meta-regression models were performed to explore heterogeneity.
Results
Ninetyone studies were included reporting 6473 IH. The pooled proportions of IH for OS were 0.35 (95% CI 0.27–0.44)
I
2
0% in midline laparotomies and 0.02 (95% CI 0.00–0.07),
I
2
52% for off-midline. In case of LS the pooled proportion of IH for midline extraction sites were 0.10 (95% CI 0.07–0.16),
I
2
58% and 0.04 (95% CI 0.03–0.06),
I
2
86% in case of off-midline. In Port-site IH was 0.02 (95% CI 0.01–0.04),
I
2
82%, and for single incision surgery (SILS) of 0.06—95% CI 0.02–0.15,
I
2
81%. In case of stoma reversal sites was 0.20 (95% CI 0.16–0.24).
Conclusion
Midline laparotomies and stoma reversal sites are at high risk for IH and should be considered in research of preventive strategies of closure. After laparoscopic approach IH happens mainly by extraction sites incisions specially midline and also represent an important area of analysis.
The PNPLA3 I148M variant (rs738409) is robustly associated with hepatic steatosis. Intriguingly, initial findings in cohorts with a mean body mass index (BMI) of 30 kg m(-2) also suggested that it is ...associated with elevated liver enzymes but not with insulin resistance and dyslipidaemia.
To determine whether the PNPLA3 variant alters the susceptibility of morbidly obese subjects to develop liver injury and metabolic sequelae.
The study was carried out in 678 obese Italians (mean BMI = 41 kg m(-2)) who were genotyped for the I148M variant. All participants provided fasting blood samples and then underwent oral glucose tolerance tests.
Indices of liver injury (alanine transaminase (ALT), aspartate transaminase (AST)), glucose tolerance and insulin resistance were measured.
Markers of hepatic injury such as ALT and AST were significantly higher in carriers of the 148M allele (P = 2.2 x 10(-5) and 0.001, respectively). In all, 50% of 148M risk allele homozygotes had pathological levels of ALT (>40 U l(-1)) compared with 25% of 148I allele homozygotes (P = 0.005). Glucose tolerance and insulin sensitivity were similar in all three genotypes.
Obese Southern Europeans carrying the 148M allele have increased indices of liver damage uncoupled from proxy measures of insulin resistance.
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