Neutron-upscattering enhancement of the triple-alpha process.

The neutron inelastic scattering of carbon-12, populating the Hoyle state, is a reaction of interest for the triple-alpha process. The inverse process (neutron upscattering) can enhance the Hoyle state's decay rate to the bound states of 12C, effectively increasing the overall triple-alpha reaction rate. The cross section of this reaction is impossible to measure experimentally but has been determined here at astrophysically-relevant energies using detailed balance. Using a highly-collimated monoenergetic beam, here we measure neutrons incident on the Texas Active Target Time Projection Chamber (TexAT TPC) filled with CO2 gas, we measure the 3α-particles (arising from the decay of the Hoyle state following inelastic scattering) and a cross section is extracted. Here we show the neutron-upscattering enhancement is observed to be much smaller than previously expected. The importance of the neutron-upscattering enhancement may therefore not be significant aside from in very particular astrophysical sites (e.g. neutron star mergers).

New Isotope

A new short-lived neutron-deficient isotope ^{220}Np was synthesized in the fusion-evaporation reaction ^{185}Re(^{40}Ar,5n)^{220}Np at the gas-filled recoil separator SHANS. Based on the measurement of the correlated α-decay chains, the decay properties of ^{220}Np with E_{α}=10040(18) keV and T_{1/2}=25_{-7}^{+14} µs were determined, which are in good agreement with theoretical predictions. From the new experimental results coupled with the recently reported α-decay data of ^{219,223}Np, the α-decay systematics for Np isotopes around N=126 was established, which allows us for the first time to test the robustness of the N=126 shell closure in Z=93 Np isotopes. The results also indicate that, in the region of nuclei with Z≥83, the proton drip line has been reached for all odd-Z isotopes up to Np.

[Coronary collateral circulation in infarction-related artery in patients with acute myocardial infarction with rise and without rise of ST segment].

The authors analyzed a condition of coronary collateral circulation in infarction-related artery in patients with acute myocardial infarction with rise and without rise of ST segment. The assessment of collateral circulation was made by coronary angiography using Rentop scale. Results of the research showed, that collateral circulation wasn't visualized by angiography in the first hours after acute myocardial infarction with the rise of ST segment. Apparently, this circulation didn't significantly assisted in maintenance of vital capacity of the myocardium in the pool of infarction-related occlusive coronary artery. Visualization of collateral circulation was noted in majority of patients with acute myocardial infarction without the rise of ST segment. Collateral flow was an important alternative source of blood supply of the heart in patients without rise of ST segment in the period of critical reduction of the antegrade blood flow.

[Coronary microvascular obstruction phenomenon after endovascular recanalization in patients with chronic coronary occlusions].

The article analyzed no-reflow phenomenon after endovascular recanalization for chronic coronary occlusion. An assessment of antegrade blood flow was made while performing the coronary angiography according to TIMI classification. The Rentrop scale was used for evaluation of retrograde blood flow. The results of investigation showed, that the frequency of occurrence of no-reflow phenomenon after endovascular recanalization in the case of chronic coronary occlusion wasn't higher than 5%. The onset of no-reflow phenomenon after endovascular recanalization in chronic coronary occlusion doesn't depend on the volume of retrograde collateral filling of distal coronary bloodstream. A postponed restoration of antegrade blood flow was possible in patients with previously manifested (Rentrop II-III) retrograde collateral filling of periphery.

Evidence for the dipole nature of the low-energy γ enhancement in 56Fe.

The γ-ray strength function of 56Fe has been measured from proton-γ coincidences for excitation energies up to ≈11 MeV. The low-energy enhancement in the γ-ray strength function, which was first discovered in the (3He,αγ)56Fe reaction, is confirmed with the (p,p'γ)56Fe experiment reported here. Angular distributions of the γ rays give for the first time evidence that the enhancement is dominated by dipole transitions.

Production and decay of the heaviest nuclei (293,294)117 and (294)118.

Two years after the discovery of element 117, we undertook a second campaign using the (249)Bk+(48)Ca reaction for further investigations of the production and decay properties of the isotopes of element 117 on a larger number of events. The experiments were started in the end of April 2012 and are still under way. This Letter presents the results obtained in 1200 hours of an experimental run with the beam dose of (48)Ca of about 1.5×10(19) particles. The (249)Bk target was irradiated at two energies of (48)Ca that correspond to the maximum probability of the reaction channels with evaporation of three and four neutrons from the excited (297)117. In this experiment, two decay chains of (294)117 (3n) and five decay chains of (293)117 (4n) were detected. In the course of the long-term work, (249)Cf-the product of decay of (249)Bk (330 d)-is being accumulated in the target. Consequently, in the present experiment, we also detected a single decay of the known isotope (294)118 that was produced during 2002-2005 in the reaction (249)Cf((48)Ca,3n)(294)118. The obtained results are compared with the data from previous experiments. The experiments are carried out in the Flerov Laboratory of Nuclear Reactions, Joint Institute for Nuclear Research, using the heavy-ion cyclotron U400.

New insights into the 243Am + 48Ca reaction products previously observed in the experiments on elements 113, 115, and 117.

Results of a new series of experiments on the study of production cross sections and decay properties of the isotopes of element 115 in the reaction (243)Am+(48)Ca are presented. Twenty-one new decay chains originating from (288)115 were established as the product of the 3n-evaporation channel by measuring the excitation function at three excitation energies of the compound nucleus (291)115. The decay properties of all newly observed nuclei are in full agreement with those we measured in 2003. At the lowest excitation energy E*=33 MeV, for the first time we registered the product of the 2n-evaporation channel, (289)115, which was also observed previously in the reaction (249)Bk+(48)Ca as the daughter nucleus of the decay of (293)117. The maximum cross section for the production of (288)115 is found to be 8.5 pb at E*≈36 MeV.

Synthesis of a new element with atomic number Z = 117.

The discovery of a new chemical element with atomic number Z=117 is reported. The isotopes (293)117 and (294)117 were produced in fusion reactions between (48)Ca and (249)Bk. Decay chains involving 11 new nuclei were identified by means of the Dubna gas-filled recoil separator. The measured decay properties show a strong rise of stability for heavier isotopes with Z > or = 111, validating the concept of the long sought island of enhanced stability for superheavy nuclei.

Enhanced radiative strength in the quasicontinuum of 117Sn.

The radiative strength function of 117Sn has been measured up to the neutron separation energy using the (3He, 3He' gamma) reaction. An increase in the slope of the strength function around E gamma=4.5 MeV indicates the onset of a resonancelike structure, giving a significant enhancement of the radiative strength function compared to standard models in the energy region 4.5

Ecosystem and human health assessment to define environmental management strategies: The case of long-term human impacts on an Arctic lake.

There are rich deposits of mineral and fossil natural resources in the Arctic, which make this region very attractive for extracting industries. Their operations have immediate and vast consequences for ecological systems, which are particularly vulnerable in this region. We are developing a management strategy for Arctic watersheds impacted by industrial production. The case study is Lake Imandra watershed (Murmansk oblast, Russia) that has exceptionally high levels of economic development and large numbers of people living there. We track the impacts of toxic pollution on ecosystem health and then--human health. Three periods are identified: (a) natural, pre-industrial state; (b) disturbed, under rapid economic development; and (c) partial recovery, during recent economic meltdown. The ecosystem is shown to transform into a qualitatively new state, which is still different from the original natural state, even after toxic loadings have substantially decreased. Fish disease where analyzed to produce and integral evaluation of ecosystem health. Accumulation of heavy metals in fish is correlated with etiology of many diseases. Dose-effect relationships are between integral water quality indices and ecosystem health indicators clearly demonstrates that existing water quality standards adopted in Russia are inadequate for Arctic regions. Health was also poor for people drinking water from the Lake. Transport of heavy metals from drinking water, into human organs, and their effect on liver and kidney diseases shows the close connection between ecosystem and human health. A management system is outlined that is based on feedback from indices of ecosystem and human health and control over economic production and/or the amount of toxic loading produced. We argue that prospects for implementation of such a system are quite bleak at this time, and that more likely we will see a continued depopulation of these Northern regions.

Large enhancement of radiative strength for soft transitions in the quasicontinuum.

Radiative strength functions (RSFs) for the (56,57)Fe nuclei below the separation energy are obtained from the 57Fe(3He,alphagamma)56Fe and 57Fe(3He,3He'gamma)57Fe reactions, respectively. An enhancement of more than a factor of 10 over common theoretical models of the soft (E(gamma) less than or approximately equal 2 MeV) RSF for transitions in the quasicontinuum (several MeV above the yrast line) is observed. Two-step cascade intensities with soft primary transitions from the 56Fe(n,2gamma)57Fe reaction confirm the enhancement.

[Lesions of the vascular endothelium and impairments of haemostatic coagulation in patients with severe craniocerebral trauma]. / Povrezhdenie sosudistogo éndoteliia i narusheniia sistemy reguliatsii agregatnogo sostoianiia krovi u bol'nykh tiazheloi cherepno-mozgovoi travmoi.

Malfunctions of central hemostasis chains, activation of blood coagulation systems and decreased antithrombogenic potentials of vascular walls are typical of craniocerebral trauma at exacerbation. It provokes the onset of the DIC-syndrome in 98.8% of examinees; the below signs are observed in such condition: decreased platelet resistance of vascular walls, increased aggregation activity of platelets, activated coagulation chain of hemostasis and increased blood viscosity. The prognostically unfavorable criteria of coagulopathy in acute craniocerebral trauma are as follows: pathological response of the vascular wall to transitory ischemia observed concurrently with a reduced dynamic FW activity; a persistently low and/or decreased dynamic AT-III activity; decreased fibrinolytic activities of plasma and platelet counts; and persistently higher concentrations and/or higher dynamic concentrations of fibrinogen and soluble fibrin mono-measured complexes (according to coagulation tests). Hemostasis should be corrected with respect to the above hemostasiologic syndromes.

[Epidemiology of chronic obstructive pulmonary diseases]. / Epidemiologiia khronicheskikh obstruktivnykh zabolevanii legkikh.

In this study the epidemiological problems of chronic obstructive pulmonary diseases in the population of the Far North are considered: prevalence of pathology, risk factors and indices of bronchial obstruction are correlated with age, sex, period of living in the North and clinical course of a disease.

[Questions on the efficiency of membrane technology in treating periodontal diseases. Experience of experimental and clinical studies]. / Voprosy éffektivnosti membrannoi tekhnologii pri lechenii zabolevani parodonta. Opyt éksperimental'nykh i klinicheskikh issledovanii.

Experimental and morphological studies demonstrated that Gore Resolute resorbable membrane can cause local inflammatory reactions similar to allergic. Collagen-based biomembranes coated with hydroxyapatite cause no local pathological reactions, but are rapidly resorbed in foci of degeneration under the effect of aggressive factors of tissue environment. Russian silicone membrane has been clinically tried with satisfactory results in patients with generalized periodontitis; the results prompt further studies of the membrane.

[Plasmapheresis in radiotherapy for pancreatic cancer]. / Plazmaferez pri luchevoi terapii raka podzheludochnoi zhelezy.

Although radiotherapy is known to improve the results of treatment for pancreatic carcinoma, its application is limited due to such side effects and complications as anemia, leuko-, thrombocytopenia and dyspeptic disorders. It was suggested that since these complications are primarily caused by radiotherapy itself and mass death of tumor cells, plasmapheresis might raise tolerance to radiation. This was confirmed by our experience with its use during radiotherapy course in 22 patients with pancreatic cancer.

[The dynamics of the healing of experimentally reproduced bone defects filled with different polyacrylamide gel-based compounds]. / Dinamika zazhivleniia éksperimental'no vosproizvedennykh kostnykh defektov, zapolnennykh razlichnymi kompozitsiiami na osnove poliakrilamidnogo gelia.

Time course of healing of standard osseous defects by introduction of polyacrylamide gel (PAG)-based materials was studied in rat experiments. PAG did not prevent the formation of soft-tissue and osseous regenerate in bone defects. Addition of hydroxyapatite, bactericidal agent, and lysozyme to PAG-based composition led in some cases to development of chronic inflammation and giant-cell reaction in osseous wound and to inhibition of the reparative processes.