Momentum Distribution in Nuclear matter within a Perturbation Approximation

It is shown that the norm corrections, introduced to avoid the violation of the constraints on the depletion of the hole states in the standard perturbative 2p2h approach, leads in nuclear matter to a dependence of the momentum distribution with the total nucleon number. This unphysical behavior, which in turn makes the depletion to be non-extensive, arises from contributions of disconnected diagrams contained in the norm. It is found that the extensivity is again recovered when the 4p4h excitations in the ground state are included, and a reasonable value for the total number of nucleons promoted above the Fermi level is obtained.Comment: 11 pages, LaTeX, 5 figures, figures 1 to 3 included in the latex file, postscript files of figures 4 and 5 available from the Authors. Accepted for publication in Phys. Rev.

Fractional Cauchy problems on bounded domains: survey of recent results

In a fractional Cauchy problem, the usual first order time derivative is replaced by a fractional derivative. This problem was first considered by \citet{nigmatullin}, and \citet{zaslavsky} in $\mathbb R^d$ for modeling some physical phenomena. The fractional derivative models time delays in a diffusion process. We will give a survey of the recent results on the fractional Cauchy problem and its generalizations on bounded domains D\subset \rd obtained in \citet{m-n-v-aop, mnv-2}. We also study the solutions of fractional Cauchy problem where the first time derivative is replaced with an infinite sum of fractional derivatives. We point out a connection to eigenvalue problems for the fractional time operators considered. The solutions to the eigenvalue problems are expressed by Mittag-Leffler functions and its generalized versions. The stochastic solution of the eigenvalue problems for the fractional derivatives are given by inverse subordinators

Ecological policy in oil-gas complexes, HSE MS implementation in oil and gas company

The paper considers the following issues: HSE MS international standard implementation in oil and gas industry, taking into account international practices; implementation of standards in oil and gas companies; policy in the field of environmental protection and occupational health and safety; achievement of planned indicators and targets in environmental protection and occupational health and safety

Impact of the COVID-19 pandemic on tuberculosis national reference laboratory services in the WHO European Region, March to November 2020.

We assessed the impact of COVID-19 on diagnostic services for tuberculosis (TB) by national reference laboratories in the WHO European Region. Of 35 laboratories, 30 reported declines in TB sample numbers, amounting up to > 50% of the pre-COVID-19 volumes. Sixteen reported reagent or consumable shortages. Nineteen reallocated ressources to SARS-CoV-2 testing, resulting in an overall increase in workload, largely without a concomitant increase in personnel (n = 14). This poses a risk to meeting the 2025 milestones of the End TB Strategy

First-Time Home Buyers and Residential Investment Volatility

Like other macroeconomic variables, residential investment has become much less volatile since the mid-1980s (recent experience notwithstanding.) This paper explores the role of structural change in this decline. Since the the early 1980s there have been many changes in the underlying structure of the economy, including those in the mortgage market which have made it easier to acquire a home. We examine how these changes affect residential investment volatility in a life-cycle model consistent with micro evidence on housing choices. We find that a decline in the rate of household formation, increased delay in marriage, and an increase in the cross-sectional variance of earnings drive the decline in volatility. Our findings provide support for the view that the Great Moderation in aggregate fluctuations is not just due to smaller aggregate shocks, but is driven at least in part by structural change

The Boundaries of Justice: The Challenges of Environmental Justice Assessments for Transportation Projects

Over recent decades, federal guidelines for transportation projects have required increasing attention to impacts on communities. Executive Order 12898 requires federal agencies to conduct environmental justice (EJ) assessments to determine if negative effects from projects will fall disproportionately on minority or low-income populations. Yet transportation agencies have not given specific guidance on the method for conducting such assessments. Therefore practitioners and researchers apply a variety of analytical techniques. This paper uses a case study of a planned road widening project in Daytona Beach, Florida, to compare the various methods currently used in EJ assessments. The choice of reference area and of method for determining the decision threshold for a finding of disproportionality are shown to have important implications for the outcome of an assessment. Because the spatial distribution of racial/ethnic and low-income groups will vary widely from place to place, practitioners and transportation agencies should not decide on the precise method, but carefully consider the characteristics and distribution of the data being used and select the method that most fairly represents the data distribution. Conducting genuine EJ assessments is not only required by federal regulations, but can head off conflicts, better reveal the true costs of projects, and allow for more equitable distribution of costs and benefits by better targeting mitigation efforts. Thus rather than shying away from EJ assessments, transportation agencies and practitioners should continue to explore methods and approaches.Master of City and Regional Plannin

Hepatic arterial chemotherapy for primary and metastatic liver cancers

Hepatic arterial chemotherapy represents a means of selectively exposing hepatic tumor to cytotoxic agents. Although 5-fluoro-2′-deoxyuridine has been shown to generate a higher response rate in the treatment of colorectal liver metastases than that achieved by intravenous infusion, responses are largely incomplete and rarely of long duration. This review describes the rationale for the use of the thymidine analogs 5-bromo-2′-deoxyuridine and 5-iodo-2′-deoxyuridine in hepatic arterial infusions and indicates how combination therapy adding radiotherapy, specifically with hepatic arterially administered yttrium-90 microspheres, might generate a new, more efficient and effective therapeutic approach.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46919/1/280_2004_Article_BF00647244.pd