3,252 research outputs found
Simulation of the response of a silicon pixel detector
A model to simulate the response of a silicon pixel detector is described. The effects of geometrical charge sharing, electronic noise threshold dispersion, capacitive coupling between pixel channels and d -rays production have been taken into account. The model has been tested on the Omega3chip, which is the direct predecessor of the ALICE pixel detector, to be used in the inner tracking system of the ALICE experiment. The model is able to reproduce the experimental data and the resulting parameters are consistent with the measurements made on the Omega3chip. Key words:silicon pixel, simulation PACS:07.05.T,29.40.
The n-acetyl phenylalanine glucosamine derivative attenuates the inflammatory/catabolic environment in a chondrocyte-synoviocyte co-culture system
Osteoarthritis (OA), the most prevalent degenerative joint disease, still lacks a true disease-modifying therapy. The involvement of the NF-κB pathway and its upstream activating kinases in OA pathogenesis has been recognized for many years. The ability of the N-acetyl phenylalanine glucosamine derivative (NAPA) to increase anabolism and reduce catabolism via inhibition of IKKα kinase has been previously observed in vitro and in vivo. The present study aims to confirm the chondroprotective effects of NAPA in an in vitro model of joint OA established with primary cells, respecting both the crosstalk between chondrocytes and synoviocytes and their phenotypes. This model satisfactorily reproduces some features of the previously investigated DMM model, such as the prominent induction of ADAMTS-5 upon inflammatory stimulation. Both gene and protein expression analysis indicated the ability of NAPA to counteract key cartilage catabolic enzymes (ADAMTS-5) and effectors (MCP-1). Molecular analysis showed the ability of NAPA to reduce IKKα nuclear translocation and H3Ser10 phosphorylation, thus inhibiting IKKα transactivation of NF-κB signalling, a pivotal step in the NF-κB-dependent gene expression of some of its targets. In conclusion, our data confirm that NAPA could truly act as a disease-modifying drug in OA
Association of a homozygous GCK missense mutation with mild diabetes
Background: Homozygous inactivating GCK mutations have been repeatedly reported to cause severe hyperglycemia, presenting as permanent neonatal diabetes mellitus (PNDM). Conversely, only two cases of GCK homozygous mutations causing mild hyperglycemia have been so far described. We here report a novel GCK mutation (c.1116G>C, p.E372D), in a family with one homozygous member showing mild hyperglycemia. Methods: GCK mutational screening was carried out by Sanger sequencing. Computational analyses to investigate pathogenicity and molecular dynamics (MD) were performed for GCK-E372D and for previously described homozygous mutations associated with mild (n = 2) or severe (n = 1) hyperglycemia, used as references. Results: Of four mildly hyperglycemic family-members, three were heterozygous and one, diagnosed in the adulthood, was homozygous for GCK-E372D. Two nondiabetic family members carried no mutations. Fasting glucose (p = 0.016) and HbA1c (p = 0.035) correlated with the number of mutated alleles (0–2). In-silico predicted pathogenicity was not correlated with the four mutations’ severity. At MD, GCK-E372D conferred protein structure flexibility intermediate between mild and severe GCK mutations. Conclusions: We present the third case of homozygous GCK mutations associated with mild hyperglycemia, rather than PNDM. Our in-silico analyses support previous evidences suggesting that protein stability plays a role in determining clinical severity of GCK mutations
The effectiveness of university regulations to foster science-based entrepreneurship
In this study, we analyze the effect of the introduction of university regulations supporting academic entrepreneurship. Using a sample of 611 companies spun-off from the 64 Italian Science, Technology, Engineering, Mathematics and Medicine (STEMM) universities between 2002 and 2012, we show that university regulations in support of academic entrepreneurship have a positive effect on the creation of academic spin-offs. Nevertheless, their effectiveness is conditioned by specific contingencies. First, the characteristics of university departments influence the positive effect of the regulation: in some cases, there is a substitution effect rather than a complementary one. Second, the design of the regulation impacts the decisions of academic staff regarding whether to start a new venture. Finally, the effect of the regulation is maximized four years after its introduction and then becomes less effective. This paper contributes to the debate on the evaluation of policies supporting science-based entrepreneurship
The Effects of Massage Therapy by the Patients Relative on Vital Signs of Males Admitted in Critical Care Unit
Background: Changes in vital signs may affect the myocardial oxygen demand. Massage therapy has been used in intensive care units to relive patients’ physical and psychological problems. In all of the studies massaging has been done by a nurse and the patients’ family did not have any role.
Objectives: The present study aimed to examine the effects of massage therapy by patient’s relative on vital signs of patients with acute coronary syndrome and acute myocardial infarction.
Patients and Methods: A randomized controlled trial was conducted on 60 male patients hospitalized in coronary care units. In the intervention group, massage therapy was done by one of the patient’s male relatives on the third day of admission. The control group only received the routine care. Vital signs were recorded before and after the massage therapy session. SPSS 11.5 software was employed to analyze data using qui-square, Fischer exact test, independent t-test, paired t-test and descriptive statistics.
Results: The pre intervention mean of systolic blood pressure of the intervention group were 126.36 ± 16.80 and changed to 121.70 ± 13.31 after the massage therapy session (P = 0.021). The mean pulse rate of the intervention group was 79.46 ± 10.41 and reached 69.30 ± 9.47 after the intervention (P = 0.001). The mean respiration rate of the intervention group also decreased after massage (P = 0.001). No significant changes were observed in diastolic blood pressure and temperature of the intervention group. No significant changes were observed in vital signs of the control group either.
Conclusions: Massage therapy by the patients’ relative, decreased systolic blood pressure, pulse and respiration rates of patients admitted in critical care Unite (CCU). Because of the useful effects of those changes, it can be recommended that massage therapy by a member of the patient’s family be used to balance vital signs of patients admitted in CCU. This study was registered at Iranian Registry of Clinical Trials (IRCT). The registration number of the study is IRCT201112048296N
Plants' responses to novel environmental pressures
Plants have been exposed to multiple environmental stressors on long-term (seasonal) and short-term (daily) basis since their appearance on land. During the last decades, however, plants have been frequently exposed to sudden changes in their environment (imposed by global change) which indeed involves the acclimation/adaptation syndrome of living organisms. The frequency of these unpredictable \u2018stress\u2019 events is expected to increase further in the near future. Such severe, even transient alterations in environmental stimuli (variables) represent new challenges to plants, which do not possess the \u2018flight\u2019 strategy usually displayed by other organisms.
Plants have developed, however, a multiplicity of highly integrated adjustments, involving morpho-anatomical, physiological and biochemical traits, to cope with challenges imposed by novel, harsher environments: these constitute the \u2018flight strategy of sessile organisms\u2019. Interestingly, several habitats threatened by the novel stresses are biodiversity hotspots. For example, Mediterranean basin, in which high light growing plants face heat waves coupled with the scarcity of rainfall of increasing frequency and severity, represents just 2% of the earth\u2019s land area, but account for 16% of the world\u2019s plant species. This implies that plants have been and are capable to display a wide range of acclimation/adaptation strategies to cope with most unfavorable environments. Nonetheless, the unpreceded rate at which climate changes may exceed the capacity of plants to acclimate and adapt successfully to the novel environmental pressures, further exacerbated by an increase in anthropogenic pressure.
Understanding the mechanisms through which plants respond to new challenges posed by the concurrent effect of different stress agents is crucial, as obvious, to develop strategies of biodiversity conservation and ecosystem functionality. This is exactly the focus of this Research Topic. Review, Opinion as well as Original Research articles are welcome covering basic and applied research on plant functioning under adverse environmental conditions. The frequency of extreme stress events, mostly due to the concurrent effects of different stressors, is increasing particularly in the arid and semi-arid regions, which represent indeed among the most fragile ecosystems worldwide. Papers dealing with the effects of multiple stress agents on plant functioning are, therefore, particularly welcome. We are, however, also interested to receive contributions dissecting response mechanisms (from molecular to organism and whole-plant levels) of plants to a wide range of individual stressors, with a view to a rapidly changing climate, covering plant responses from other regions of the world. These include, but are not limited to drought and heat stress, excess light stress (including UV radiation), cold, ozone and rising CO2 concentration, and their combinations. Theories that predict the plant behavior, acclimation and plant plasticity are also inside the scope of this topi
Co-axial dual-core resonant leaky fibre for optical amplifiers
We present a co-axial dual-core resonant leaky optical fibre design, in which
the outer core is made highly leaky. A suitable choice of parameters can enable
us to resonantly couple power from the inner core to the outer core. In a
large-core fibre, such a resonant coupling can considerably increase the
differential leakage loss between the fundamental and the higher order modes
and can result in effective single-mode operation. In a small-core single-mode
fibre, such a coupling can lead to sharp increase in the wavelength dependent
leakage loss near the resonant wavelength and can be utilized for the
suppression of amplified spontaneous emission and thereby gain equalization of
an optical amplifier. We study the propagation characteristics of the fibre
using the transfer matrix method and present an example of each, the
large-mode-area design for high power amplifiers and the wavelength tunable
leakage loss design for inherent gain equalization of optical amplifiers.Comment: 6 page
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