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1.
Carbon monoxide (CO) can be used to treat fresh meat and fish in order to retain its ‘fresh’ red colour appearance for a longer period of time. In fact, upon aging, myoglobin is oxidized to met-myoglobin with the concomitant blue-shift and broadening of the Soret maximum, which brings about a change in the colour of the fish, revealing that it is no longer fresh. The use of carbon monoxide, which reacts with the oxy-myoglobin to form a fairly stable cherry red carboxy-myoglobin complex may mask spoilage, because the CO-complex can be stable beyond the microbiological shelf life of the meat. The presence of CO in tuna fish has been investigated by optical spectroscopy as the formation of the CO adduct can be easily detected by the combined analysis of electronic absorption spectra in their normal and second derivative modes, monitoring the intense Soret band at 420 nm. The presence of met- and oxy-myoglobin can obscure the presence of small amounts of the CO adduct; however, it can be revealed by chemically reducing the met- and oxy-forms to the deoxy-form in an anaerobic environment. This spectroscopic method provides a qualitatively rapid laboratory screening procedure for food control to unmask the presence of CO in frozen or fresh fish.  相似文献   
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The restart of the Large Hadron Collider (LHC) at CERN, foreseen in November 2009 after the incident of 2008, will finally open a new window on the physics at the TeV scale and will allow the discovery of the Standard Model Higgs boson, if it exists, or of possible alternative schemes for the spontaneous symmetry-breaking mechanism. Moreover the LHC Collider will hopefully provide an answer to one of the most compelling questions of today coming from astronomical observations, astrophysics and cosmic ray experiments: which is the particle physics candidate for the Dark Matter component of the Universe? Supersymmetry (SUSY) is a theoretically attractive scenario for physics beyond the Standard Model which can provide a suitable Dark Matter candidate in case R-parity is conserved. If SUSY is manifesting at the TeV scale, as favored by several arguments, it will be accessible at the LHC Collider within the first few years of data taking. In this paper search strategies for a generic SUSY models with R-parity conservation with the ATLAS detector are described. These inclusive search strategies are based on signatures with missing transverse momentum from undetected neutralinos, in addition to multiple hard jets and leptons. The corresponding discovery reach for the first fb−1 of integrated luminosity of ATLAS data will be presented together with a discussion of possible measurements needed to extract the masses of SUSY particles including the Lightest Supersymmetric Particle (LSP), which in various supersymmetric (SUSY) symmetry breaking scenarios, is the lightest neutralino .  相似文献   
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We present the performance of a hodoscope made of resistive plate chambers (RPC) installed in the RD5 experiment at CERN and exposed to beams of high energy muons and pions. The efficiency as a function of the particle flux is studied for different resistivities. A substantial improvement is obtained with plates of lower resistivity. Tracking muons through the RPC and using the bending power of a 2.7 Tm iron toroid, a simple trigger algorithm is used to select large momentum muons.  相似文献   
5.
Epidemiological data have demonstrated a significant association between the presence of type 2 diabetes mellitus (T2DM) and the development of colorectal cancer (CRC). Chronic hyperglycemia, insulin resistance, oxidative stress, and inflammation, the processes inherent to T2DM, also play active roles in the onset and progression of CRC. Recently, small dense low-density lipoprotein (LDL) particles, a typical characteristic of diabetic dyslipidemia, emerged as another possible underlying link between T2DM and CRC. Growing evidence suggests that antidiabetic medications may have beneficial effects in CRC prevention. According to findings from a limited number of preclinical and clinical studies, glucagon-like peptide-1 receptor agonists (GLP-1RAs) could be a promising strategy in reducing the incidence of CRC in patients with diabetes. However, available findings are inconclusive, and further studies are required. In this review, novel evidence on molecular mechanisms linking T2DM with CRC development, progression, and survival will be discussed. In addition, the potential role of GLP-1RAs therapies in CRC prevention will also be evaluated.  相似文献   
6.
Alzheimer’s Disease (AD) is the most common cause of dementia, having a remarkable social and healthcare burden worldwide. Amyloid β (Aβ) and protein Tau aggregates are disease hallmarks and key players in AD pathogenesis. However, it has been hypothesized that microglia can contribute to AD pathophysiology, as well. Microglia are CNS-resident immune cells belonging to the myeloid lineage of the innate arm of immunity. Under physiological conditions, microglia are in constant motion in order to carry on their housekeeping function, and they maintain an anti-inflammatory, quiescent state, with low expression of cytokines and no phagocytic activity. Upon various stimuli (debris, ATP, misfolded proteins, aggregates and pathogens), microglia acquire a phagocytic function and overexpress cytokine gene modules. This process is generally regarded as microglia activation and implies that the production of pro-inflammatory cytokines is counterbalanced by the synthesis and the release of anti-inflammatory molecules. This mechanism avoids excessive inflammatory response and inappropriate microglial activation, which causes tissue damage and brain homeostasis impairment. Once the pathogenic stimulus has been cleared, activated microglia return to the naïve, anti-inflammatory state. Upon repeated stimuli (as in the case of Aβ deposition in the early stage of AD), activated microglia shift toward a less protective, neurotoxic phenotype, known as “primed” microglia. The main characteristic of primed microglia is their lower capability to turn back toward the naïve, anti-inflammatory state, which makes these cells prone to chronic activation and favours chronic inflammation in the brain. Primed microglia have impaired defence capacity against injury and detrimental effects on the brain microenvironment. Additionally, priming has been associated with AD onset and progression and can represent a promising target for AD treatment strategies. Many factors (genetics, environmental factors, baseline inflammatory status of microglia, ageing) generate an aberrantly activated phenotype that undergoes priming easier and earlier than normally activated microglia do. Novel, promising targets for therapeutic strategies for AD have been sought in the field of microglia activation and, importantly, among those factors influencing the baseline status of these cells. The CX3CL1 pathway could be a valuable target treatment approach in AD, although preliminary findings from the studies in this field are controversial. The current review aims to summarize state of the art on the role of microglia dysfunction in AD pathogenesis and proposes biochemical pathways with possible targets for AD treatment.  相似文献   
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This study describes the presence of nitric oxide synthase (NOS-ir) immunoreactive neurons in the thalamic ventrobasal complex of the cat. NOS-ir is co-localized with gamma-aminobutyric acid (GABA-ir) in a subset of small neurons identified as local circuit neurons in previous studies. The double labeled neurons are further identified by a larger soma diameter when compared to GABA-ir only neurons. All NOS-ir somata exhibit GABA-ir but none exhibit immunoreactivity to calbindin.  相似文献   
9.
In order to ensure that the resistive plate chambers used in the ATLAS experiment will not show, during their operation, any abnormal aging effect which could degrade their performances, an aging test is being performed at X5-GIF, CERN's gamma irradiation facility. In this paper, the latest results are presented, together with an example of successful damage recovery technique.  相似文献   
10.
Natural killer (NK) cells play a role in defence against viral infections by killing infected cells or by producing cytokines and interacting with adaptive immune cells. Killer immunoglobulin-like receptors (KIRs) regulate the activation of NK cells through their interaction with human leucocyte antigens (HLA). Ninety-six Sicilian patients positive to Human Immunodeficiency Virus-1 (HIV) and ninety-two Sicilian patients positive to SARS-CoV-2 were genotyped for KIRs and their HLA ligands. We also included fifty-six Sicilian patients with chronic hepatitis B (CHB) already recruited in our previous study. The aim of this study was to compare the distribution of KIR–HLA genes/groups of these three different infected populations with healthy Sicilian donors from the literature. We showed that the inhibitory KIR3DL1 gene and the KIR3DL1/HLA-B Bw4 pairing were more prevalent in individual CHB. At the same time, the frequency of HLA-C2 was increased in CHB compared to other groups. In contrast, the HLA-C1 ligand seems to have no contribution to CHB progression whereas it was significantly higher in COVID-19 and HIV-positive than healthy controls. These results suggest that specific KIR–HLA combinations can predict the outcome/susceptibility of these viral infections and allows to plan successful customized therapeutic strategies.  相似文献   
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