Nuclear Medium Modifications of Hadrons from Generalized Parton Distributions

We study the structure of generalized parton distributions in spin 0 nuclei within a microscopic approach for nuclear dynamics. GPDs can be used on one side as tools to unravel the deep inelastic transverse structure of nuclei in terms of both transverse spatial and transverse momentum degrees of freedom. On the other, one can obtain information on GPDs themselves by observing how they become modified in the nuclear environment. We derive the structure of the nuclear deeply virtual Compton scattering tensor and generalized parton distributions at leading order in $Q$ in a field-theoretical framework. The nuclear generalized parton distributions are calculated using a two step process -- the convolution approach -- where the scattering process happens from a quark inside a nucleon, itself inside a nucleus, disregarding final state interactions with both the nuclear and nucleon debris. We point out that details of the nuclear long range interactions such as two-body currents, can be disregarded compared to the deep inelastic induced modifications of the bound GPDs. We show how the pattern of nuclear modifications predicted, and in particular the deviations of off-shell effects from the longitudinal convolution provide clear signals to be sought in experimental measurements. Finally, we find interesting relationships by studying Mellin moments in nuclei: in particular we predict the $A$-dependence for the $D$-term of GPDs within a microscopic approach, and the behavior with $t$ of the total momentum carried by quarks in a nucleus. The latter provides an important element for the evaluation of nuclear hadronization phenomena which are vital for interpreting current and future data at RHIC, HERMES and Jefferson Lab.Comment: 29 pages, 10 figure

Air freight : the problems of airport restrictions : final report on the Conference of Air Cargo Industry Considerations of Airport Curfews

April 1979Conference held in Jupiter, Fla. in January 1979Includes bibliographical references (p. 36)Noise due to aircraft was considered to be a potential problem as far back as 1952, when the Doolittle Commission established by President Truman urged that a major effort be made to reduce aircraft noise. With the 'advent of the jet age in the late 1950's and the concomitant spread of suburbs towards airports in major cities such as New York, Denver, and Minneapolis-St. Paul, many more people became exposed to noise, and concern and anger intensified. Although only a small percentage (estimated at about 2-3%) of the total population of the U.S. is affected by high noise levels, these people and their representatives have been quite vocal about their dissatisfaction with noise abatement progress, even though technological advances have reduced the noise emanating from aircraft engines. As a result, the airports, the communities, and the federal government are seeking additional measures that will further diminish the noise impact of aircraft and airport operations. The dilemma is to decrease noise with the minimum economic disruptions to commerce, the community, and the aviation industry. Since very few people like to travel during the night hours (approximately 10 p.m. - 7 a.m.), and indeed very few aircraft operations take place (less than 5% of total operations at most airports), an environmentally and politically appealing option to diminish the effect of aircraft noise is to ban airplane operations during nighttime hours. However, a disproportionate number of operations at night are dedicated to cargo (about 50% of scheduled domestic all-cargo flights), and it is upon the air cargo industry and those users dependent upon nighttime flights that the major burden of a curfew would fall. The benefits of curfews are apparent; the economic penalties associated with them are not. To address this issue, the Flight Transportation Laboratory of the Massachusetts Institute of Technology hosted a week-long conference at Jupiter, Florida, in January, 1979, on the impact of airport use restrictions on air freight. This conference was sponsored by the Federal Aviation Administration and the Port Authority of New York and New Jersey. More than 70 participants, including some 50 panelists and speakers, represented various viewpoints of the air cargo industry: the users, the airlines, the airports, the communities, and various governmental agencies

A retrospective, observational, real-world evidence study to understand the clinical and obstetric characteristics and tolerability profile of women in labor managed with camylofin dihydrochloride injection

Background: To determine the clinical and obstetric characteristics and tolerability profile of pregnant women in the active phase of labor who were managed with Camylofin dihydrochloride injection.Methods: Retrospective data of 210 full-term pregnant women in the active phase of labor who were managed with Camylofin injection doses of 50 mg, 50+25 mg and 50+50 mg were considered in the study. The comparative effectiveness of 3 doses was evaluated using independent T-test and ANOVA at 5% level of significance.Results: The overall mean maternal age was 25.4 (±4.14) years with mean gestational age of 38.8 (±1.04) weeks. In total, 77.1% (n=162) of patients needed 50 mg dose of Camylofin injection for adequate cervical dilatation, and additional doses of 25 mg or 50 mg were required in 16.7% (n=35) and 6.2% (n=13), of patients, respectively to accelerate the labor. The mean cervical dilatation rates increasing dose viz 2.8 cm/hr, 4.1 cm/hr and 2.9 cm/hr, respectively. The adverse events were 14.8% (n=23) in 50 mg arm, 34.3% (n=12) in 50+25 arm and 69.0% (n=9) in 50+50 arm. Of the total, 34 events (50.0%) were related to Camylofin dihydrochloride injection, i.e. ADRs.The means of cervical dilation rate, active phase duration and total duration of labor were statistically significant (p-value <0.001) for 50 mg versus 50+25 mg.Conclusions: The study infers Camylofin injection usage with consideration of dose escalation in the routine clinical management of labor. Both mother and neonate had shown comparable tolerability profile across the three dosage arms with minimal events

The Present status and the projected programme on niobium-tantalum metallurgy in India

Niobium and tantalum which belong to the family of ref-ractory rare metals, have assumed great strategic impo-rtance in present day material development programmes, specially in industries like chemical and nuclear engineering, electronics and aerospace. The use of niob-ium as ferroniobium contributing to carbide stabilisat-ion in stainless steel is well established and accounts for the major demand for niobium in the world today. At the same time, niobium-based alloys have been considered excellent for high temperature service, and in particular two alloys (i) SU-16 (Nb- 11 W- 3Mo -21-If-0 - 08C), and (ii) Nb-752 (Nb-IOW- 25Zr)'--have been developed for application in aerospace structure components. With its relatively low neutron absorption cross-section (Q8= I 1 barns), compatibility both with uranium fuels and liquid metal coolants, and good high temperature strength and fabrication characteristics, niobium is also an attra-ctive candidate for nuclear energy application, parti-cularly in fast reactors. Also, a zirconium-alloy conta-ining 2.5% of niobium is a potential competitor to zircaloy for structural core components in water-cooled thermal reactor systems

Maintenance cost studies of rotary wing commercial transport aircraft

December 1974Includes bibliographical references (p. 121-123)Introduction: The vertical take-off and landing (VTOL) aircraft market has had substantial growth in the period of the last ten years when one considers the overall number of aircraft in use. The military fleet has continued to increase, as have such operators as natural resource (petroleum and lumber) companies, and law enforcement agencies. (See Table 1.) In scheduled passenger service, however, the VTOL- market has not enjoyed sustained growth. Consider Table 2, the type and number of helicopters in passenger service during 1962-1972. Following the cessation of federal subsidies to helicopter operators in 1966 the number of aircraft (and total available seats) has been steadily declining. Table 3 shows the composition of the fleets of the certificated carriers since 1966. Los Angeles Airways has been in bankruptcy since 1969; Chicago Helicopter is now largely a charter operator, although retaining its certificate; New York Airways, after a period of experimentation with the fixed wing Twin Otter (DHC-6) in 1968-1969, finally made it into the black in 1973, flying Sikorsky S-61's; and SFO Helicopter has retrenched its passenger services severely, but is not yet profitable. Why is the state of scheduled passenger operations so bleak? Many answers to this question have been given. For example, it has been said that the aircraft used by the operators have been inadequate: that they have been designed for military use and are ill suited for civilians who have been used to a higher comfort level (especially since most flights taken on a helicopter are in conjunction with a ride on a large, comfortable jet transport). Alternatively, it has been said that the high cost of operating the current helicopter fleet has caused the ticket price to be too high to be attractive to the traveler. Sometimes the operators have been fingered as the culprits -- that they have not priced their product adequately and have structured their networks poorly, i.e., that the failure has been one of management and marketing. And from the purely technology minded, the answer has been that once the properly designed rotary wing aircraft arrives on the scene -- one designed for civilian use and having the proper payload-range configuration -- the market will boom as VTOL aircraft enter city-center to city-center service. Doubtless there is a kernel -of truth in all these explanations, and examples to sustain most of them can be found in the history of helicopter operations in the United States. The intent of the work described in this report was to explore one frequently cited cause of the problem of high operating costs of helicopters in scheduled service - to wit, high maintenance costs of rotary wing aircraft. This attempt was made to allow a look ahead and to predict trends in maintenance costs of future rotary wing aircraft.This work was performed under a NASA Contract for Ames Research Cente

Ionization Constants of Some Hydroxycoumarins in Dioxane-Water & Ethanol- Water Media

126-12

On the A-dependence of nuclear generalized parton distributions

We perform a microscopic evaluation of nuclear GPDs for spin-0 nuclei in the framework of the Walecka model. We demonstrate that the meson (non-nucleon) degrees of freedom dramatically influence nuclear GPDs, which is revealed in the non-trivial and unexpected A-dependence of DVCS observables. In particular, we find that the first moment of the nuclear D-term, d_A(0) ~ A^2.26, which confirms the earlier prediction of M.Polyakov. We find that in the HERMES kinematics, contrary to the free proton case, the nuclear meson degrees of freedom in large nuclei enhance the nuclear DVCS amplitude which becomes comparable to the Bethe-Heitler amplitude, and, thus, give the non-trivial A-dependence to the DVCS asymmetries: as a function of the atomic number the beam-charge asymmetry increases whereas the beam-spin asymmetry decreases slowly.Comment: Final version published in J. Phys. G. 17 pages, 9 figure

Enhanced Mucosal Antibody Production and Protection against Respiratory Infections Following an Orally Administered Bacterial Extract

Secondary bacterial infections following influenza infection are a pressing problem facing respiratory medicine. Although antibiotic treatment has been highly successful over recent decades, fatalities due to secondary bacterial infections remain one of the leading causes of death associated with influenza. We have assessed whether administration of a bacterial extract alone is sufficient to potentiate immune responses and protect against primary infection with influenza, and secondary infections with either Streptococcus pneumoniae or Klebsiella pneumoniae in mice. We show that oral administration with the bacterial extract, OM-85, leads to a maturation of dendritic cells and B-cells characterized by increases in MHC II, CD86, and CD40, and a reduction in ICOSL. Improved immune responsiveness against influenza virus reduced the threshold of susceptibility to secondary bacterial infections, and thus protected the mice. The protection was associated with enhanced polyclonal B-cell activation and release of antibodies that were effective at neutralizing the virus. Taken together, these data show that oral administration of bacterial extracts provides sufficient mucosal immune stimulation to protect mice against a respiratory tract viral infection and associated sequelae

Folate, but not vitamin B-12 status, predicts respiratory morbidity in north Indian children

Background: Vitamin deficiencies are often part of malnutrition, which predisposes to acute lower respiratory tract infections. Objective: The objective was to measure the association between cobalamin and folate status and subsequent respiratory morbidity. Design: A prospective cohort study was conducted in 2482 children aged 6-30 mo nested in a zinc supplementation trial. We measured plasma concentrations of folate, cobalamin, methylmalonic acid, and total homocysteine (tHcy) and followed the children for 4 mo. Results: We observed 1176 episodes of acute lower respiratory tract infections. Children with folate concentrations in the lowest quartile (interquartile range: 6.4-20.0 nmol/L) had a 44% higher incidence [adjusted incidence rate ratio (IRR): 1.44; 95% CI: 1.23, 1.70] of acute lower respiratory tract infections than did children in the other 3 quartiles. For tHcy, the IRR was 1.24 (1.07, 1.40) in a comparison of those in the highest quartile with those in the other quartiles. Breastfeeding was associated with high folate concentrations and protection against subsequent respiratory tract infections. This protection was significantly and substantially reduced after adjustment for plasma folate concentrations at baseline. Compared with the children in the other 3 quartiles, the IRR for being in the lowest quartile of cobalamin was 1.13 (0.76, 1.03) and for being in the highest quartile of methylmalonic acid was 1.12 (0.96, 1.31). Conclusions: Poor folate status appears to be an independent risk factor for lower respiratory tract infections in young children. This study also suggests that the protective effect of breastfeeding is partly mediated by folate provided through breast milk