Higgs potential bounds on extra quark-lepton generations

We consider the bounds for the values of higgs mass $M_H$ and of the mass of the extra quarks and leptons $M_{extra}$ derived from the stability of vacuum and from the absence of Landau pole in Higgs potential. We find that in the case of the absence of new physics up to the GUT scale the bounds for the mass of the 4th generation are so restrictive that the negative result of CDF search for extra quarks closes the window for fourth generation. In the case of the absence of new physics up to $10^5$ GeV we get weaker but still nontrivial bounds on $M_H$ and $M_{extra}$ as well.Comment: 7pp, LaTeX, uses epsf, 5 figures, PS file available at http://venus.itep.ru/preprints/1995/95058.ps.g

Evaluating recruitment methods of patients with advanced cancer: a pragmatic opportunistic comparison

YesBackground: Recruitment of patients with advanced cancer into studies is challenging. Objective: To evaluate recruitment methods in a study of pharmacist-led cancer pain medicines consultations and produce recommendations for future studies. Method: Two methods of recruitment were employed: 1) community-based (general practitioner computer search, identification by general practitioner, community pharmacist or district nurse and hospital outpatient list search), and 2) hospice-based (in and outpatient list search). Patients identified in method 1 were invited by post and in method 2 were invited face-to-face. Information was designed in collaboration with patients and carers. Results: 128 patients were identified (85 from the community and 43 from the hospice), 47 met the inclusion criteria. Twenty-three agreed to take part and 19 completed the study, 17 of whom were already under specialist palliative care. Recruitment rates were 7% for community-based methods and 40% for hospice. The recruitment methods differed in intensity of resource use. Recruitment via letter and a lack of engagement by healthcare professionals were found to be barriers. Facilitators included the researcher having personal involvement in recruitment. Conclusion: The overall recruitment rate was in line with other studies for this patient cohort. Attempts to identify and engage patients through community-based postal contact were less effective than where personal contact with patients was both possible and occurred. Methods were less successful at recruiting patients who were not already engaged with hospice services.Programme Grants for Applied Research. Grant Number: RP-PG-0610-1011

Numerical study of chiral symmetry breaking in non-Abelian gauge theory with background magnetic field

We investigate the effect of a uniform background magnetic field on the chiral symmetry breaking in SU(2) Yang-Mills theory on the lattice. We observe that the chiral condensate grows linearly with the field strength B up to \sqrt{e B} = 3 GeV as predicted by chiral perturbation theory for full QCD. As the temperature increases the coefficient in front of the linear term gets smaller. In the magnetic field near-zero eigenmodes of the Dirac operator tend to have more regular structure with larger (compared to zero-field case) Hausdorff dimensionality. We suggest that the delocalization of near-zero eigenmodes plays a crucial role in the enhancement of the chiral symmetry breaking.Comment: 6 pages, Elsevier article style, 5 figures; revision: references and discussions added, published versio

Recent advance in high manufacturing readiness level and high temperature CMOS mixed-signal integrated circuits on silicon carbide

A high manufacturing readiness level silicon carbide (SiC) CMOS technology is presented. The unique process flow enables the monolithic integration of pMOS and nMOS transistors with passive circuit elements capable of operation at temperatures of 300 °C and beyond. Critical to this functionality is the behaviour of the gate dielectric and data for high temperature capacitance–voltage measurements are reported for SiO2/4H-SiC (n and p type) MOS structures. In addition, a summary of the long term reliability for a range of structures including contact chains to both n-type and p-type SiC, as well as simple logic circuits is presented, showing function after 2000 h at 300 °C. Circuit data is also presented for the performance of digital logic devices, a 4 to 1 analogue multiplexer and a configurable timer operating over a wide temperature range. A high temperature micro-oven system has been utilised to enable the high temperature testing and stressing of units assembled in ceramic dual in line packages, including a high temperature small form-factor SiC based bridge leg power module prototype, operated for over 1000 h at 300 °C. The data presented show that SiC CMOS is a key enabling technology in high temperature integrated circuit design. In particular it provides the ability to realise sensor interface circuits capable of operating above 300 °C, accommodate shifts in key parameters enabling deployment in applications including automotive, aerospace and deep well drilling

Evaluation of the modified FINDRISC to identify individuals at high risk for diabetes among middle-aged white and black ARIC study participants

Objective: To evaluate a modified Finnish Diabetes Risk Score (FINDRISC) for predicting the risk of incident diabetes among white and black middle-aged participants from the Atherosclerosis Risk in Communities (ARIC) study. Research design and methods: We assessed 9754 ARIC cohort participants who were free of diabetes at baseline. Logistic regression and receiver operator characteristic (ROC) curves were used to evaluate a modified FINDRISC for predicting incident diabetes after 9 years of follow-up, overall and by race/gender group. The modified FINDRISC used comprised age, body mass index, waist circumference, blood pressure medication and family history. Results: The mean FINDRISC (range, 2 [lowest risk] to 17 [highest risk]) for black women was higher (9.9 ± 3.6) than that for black men (7.6 ± 3.9), white women (8.0 ± 3.6) and white men (7.6 ± 3.5). The incidence of diabetes increased generally across deciles of FINDRISC for all 4 race/gender groups. ROC curve statistics for the FINDRISC showed the highest area under the curve for white women (0.77) and the lowest for black men (0.70). Conclusions: We used a modified FINDRISC to predict the 9-year risk of incident diabetes in a biracial US population. The modified risk score can be useful for early screening of incident diabetes in biracial populations, which may be helpful for early interventions to delay or prevent diabetes

The Values of mtm_t and αsˉ\bar{\alpha_s} Derived from the Non-Observation of Electroweak Radiative Corrections at LEP: Global Fit

A set of equations representing the $W/Z$ mass ratio and various observables of $Z$ decays in terms of $\bar\alpha \equiv\alpha (m_Z)$, $G_{\mu}$, $m_Z$, $m_t$, $m_H$, $\bar\alpha_{s} \equiv\alpha_{s} (m_Z)$, $m_b$ and $m_\tau$ (all other fermion masses being neglected) are compared with the latest data of the four LEP detectors, which at the level of one standard deviation coincide with their Born values. Our global fit gives: $m_t = 161^{+ 15 +16}_{-16 -22} \bar\alpha_{s} = 0.119 \pm 0.006 \pm 0.002$, where the central values correspond to $m_H = 300$ GeV, the first errors are statistical and the second ones represent shifts of the central values corresponding to $m_H = 1000$ GeV($+$) and 60 GeV($-$). The predicted mass of the top is smaller than in the recent fits by 4 GeV. The {\it predicted} values of $m_W/m_Z$ and the LEP observables, based on the fitted values of $m_t$ and $\bar{\alpha}_s$, show a weak dependence on $m_H$ and differ by several {\it predicted} standard deviations from the corresponding Born values. The uncertainties of the predicted values and their deviations from the corresponding Born values determine the experimental accuracy required to observe electroweak radiative corrections.Comment: LaTex, 15 pages (including 3 figures as EPS files at the end

Climate resilience in marine protected areas and the ‘Protection Paradox’

Restricting human activities through Marine Protected Areas (MPAs) is assumed to create more resilient biological communities with a greater capacity to resist and recover following climate events. Here we review the evidence linking protection from local pressures (e.g., fishing and habitat destruction) with increased resilience. Despite strong theoretical underpinnings, studies have only rarely attributed resilience responses to the recovery of food webs and habitats, and increases in the diversity of communities and populations. When detected, resistance to ocean warming and recovery after extreme events in MPAs have small effect sizes against a backdrop of natural variability. By contrast, large die-offs are well described from MPAs following climate stress events. This may be in part because protection from one set of pressures or drivers (such as fishing) can select for species that are highly sensitive to others (such as warming), creating a ‘Protection Paradox’. Given that climate change is overwhelming the resilience capacity of marine ecosystems, the only primary solution is to reduce carbon emissions. High-quality monitoring data in both space and time can also identify emergent resilience signals that do exist, in combination with adequate reference data to quantify the initial system state. This knowledge will allow networks of diverse protected areas to incorporate spatial refugia against climate change, and identify resilient biological components of natural systems. Sufficient spatial replication further offers insurance against losses in any given MPA, and the possibility for many weak signals of resilience to accumulate

Parameters affecting the enhanced permeability and retention effect: the need for patient selection

The enhanced permeability and retention (EPR) effect constitutes the rationale by which nanotechnologies selectively target drugs to tumors. Despite promising pre-clinical and clinical results, these technologies have, in our view, underachieved compared to their potential, possibly due to a suboptimal exploitation of the EPR effect. Here, we have systematically analyzed clinical data to identify key parameters affecting the extent of the EPR effect. An analysis of 17 clinical studies showed that the magnitude of the EPR effect was varied and was influenced by tumor type and size. Pancreatic, colon, breast, and stomach cancers showed the highest levels of accumulation of nanomedicines. Tumor size also had an effect on the accumulation of nanomedicines, with large size tumors having higher accumulation than both medium- and very large- sized tumors. However, medium tumors had the highest percentage of cases (100% of patients) with evidence of the EPR effect. Moreover, tumor perfusion, angiogenesis, inflammation in tumor tissues, and other factors also emerged as additional parameters that might affect the accumulation of nanomedicines into tumors. At the end of the commentary, we propose two strategies for identification of suitable patient sub-populations, with respect to the EPR effect, in order to maximize therapeutic outcome

Does congenital deafness affect the structural and functional architecture of primary visual cortex?

Deafness results in greater reliance on the remaining senses. It is unknown whether the cortical architecture of the intact senses is optimized to compensate for lost input. Here we performed widefield population receptive field (pRF) mapping of primary visual cortex (V1) with functional magnetic resonance imaging (fMRI) in hearing and congenitally deaf participants, all of whom had learnt sign language after the age of 10 years. We found larger pRFs encoding the peripheral visual field of deaf compared to hearing participants. This was likely driven by larger facilitatory center zones of the pRF profile concentrated in the near and far periphery in the deaf group. pRF density was comparable between groups, indicating pRFs overlapped more in the deaf group. This could suggest that a coarse coding strategy underlies enhanced peripheral visual skills in deaf people. Cortical thickness was also decreased in V1 in the deaf group. These findings suggest deafness causes structural and functional plasticity at the earliest stages of visual cortex