Лазерное инициирование порошков тэна в условиях объемного сжатия

Определены энергетические пороги инициирования и исследована кинетика процесса взрывного разложения порошков тетранитрата пентаэритрита, объемносжатых до давления 5·108Н/м2, при воздействии импульсом лазерного излучения на длинах волн 1064 нм (область прозрачности) и 266 нм (область собственного поглощения). Реализованы условия низкопорогового инициирования для порошков чистого тэна первой, второй и четвертой гармониках излучения неодимового лазера

Multilayer neural networks with extensively many hidden units

The information processing abilities of a multilayer neural network with a number of hidden units scaling as the input dimension are studied using statistical mechanics methods. The mapping from the input layer to the hidden units is performed by general symmetric Boolean functions whereas the hidden layer is connected to the output by either discrete or continuous couplings. Introducing an overlap in the space of Boolean functions as order parameter the storage capacity if found to scale with the logarithm of the number of implementable Boolean functions. The generalization behaviour is smooth for continuous couplings and shows a discontinuous transition to perfect generalization for discrete ones.Comment: 4 pages, 2 figure

A multi-detector array for high energy nuclear e+e- pair spectrosocopy

A multi-detector array has been constructed for the simultaneous measurement of energy- and angular correlation of electron-positron pairs produced in internal pair conversion (IPC) of nuclear transitions up to 18 MeV. The response functions of the individual detectors have been measured with mono-energetic beams of electrons. Experimental results obtained with 1.6 MeV protons on targets containing $^{11}$B and $^{19}$F show clear IPC over a wide angular range. A comparison with GEANT simulations demonstrates that angular correlations of $e^+e^-$ pairs of transitions in the energy range between 6 and 18 MeV can be determined with sufficient resolution and efficiency to search for deviations from IPC due to the creation and subsequent decay into $e^+e^-$ of a hypothetical short-lived neutral boson.Comment: 20 pages, 8 figure

DNA-cellulose: an economical, fully recyclable and highly effective chiral biomaterial for asymmetric catalysis

similarity_check: This document is Similarity Check deposited related_data: Supplementary Information copyright_licence: The Royal Society of Chemistry has an exclusive publication licence for this journal peer_review_method: Single-blind history: Received 20 December 2014; Accepted 11 January 2015; Accepted Manuscript published 14 January 2015; Advance Article published 23 January 2015; Version of Record published 24 March 2015This research was supported by the Ministe`re de l’Enseignement Supe´rieur et de la Recherche and the Agence Nationale de la Recherche (NCiS; ANR-2010-JCJC-715-1)

First principles calculation of structural and magnetic properties for Fe monolayers and bilayers on W(110)

Structure optimizations were performed for 1 and 2 monolayers (ML) of Fe on a 5 ML W(110) substrate employing the all-electron full-potential linearized augmented plane-wave (FP-LAPW) method. The magnetic moments were also obtained for the converged and optimized structures. We find significant contractions ($\sim$ 10 %) for both the Fe-W and the neighboring Fe-Fe interlayer spacings compared to the corresponding bulk W-W and Fe-Fe interlayer spacings. Compared to the Fe bcc bulk moment of 2.2 $\mu_B$, the magnetic moment for the surface layer of Fe is enhanced (i) by 15% to 2.54 $\mu_B$ for 1 ML Fe/5 ML W(110), and (ii) by 29% to 2.84 $\mu_B$ for 2 ML Fe/5 ML W(110). The inner Fe layer for 2 ML Fe/5 ML W(110) has a bulk-like moment of 2.3 $\mu_B$. These results agree well with previous experimental data

CLASP2: The Chromospheric LAyer Spectro-Polarimeter

A major remaining challenge for heliophysicsis to decipher the magnetic structure of the chromosphere, due to its "large role in defining how energy is transported into the corona and solar wind" (NASA's Heliophysics Roadmap). Recent observational advances enabled by the Interface Region Imaging Spectrometer (IRIS) have revolutionized our view of the critical role this highly dynamic interface between the photosphere and corona plays in energizing and structuring the outer solar atmosphere. Despite these advances, a major impediment to better understanding the solar atmosphere is our lack of empirical knowledge regarding the direction and strength of the magnetic field in the upper chromosphere. Such measurements are crucial to address several major unresolved issues in solar physics: for example, to constrain the energy flux carried by the Alfven waves propagating through the chromosphere (De Pontieuet al., 2014), and to determine the height at which the plasma Beta = 1 transition occurs, which has important consequences for the braiding of magnetic fields (Cirtainet al., 2013; Guerreiroet al., 2014), for propagation and mode conversion of waves (Tian et al., 2014a; Straus et al., 2008) and for non-linear force-free extrapolation methods that are key to determining what drives instabilities such as flares or coronal mass ejections (e.g.,De Rosa et al., 2009). The most reliable method used to determine the solar magnetic field vector is the observation and interpretation of polarization signals in spectral lines, associated with the Zeeman and Hanle effects. Magnetically sensitive ultraviolet spectral lines formed in the upper chromosphere and transition region provide a powerful tool with which to probe this key boundary region (e.g., Trujillo Bueno, 2014). Probing the magnetic nature of the chromosphere requires measurement of the Stokes I, Q, U and V profiles of the relevant spectral lines (of which Q, U and V encode the magnetic field information)

Use of a colonoscope for distal duodenal stent placement in patients with malignant obstruction

Background: Stent placement in the distal duodenum or proximal jejunum with a therapeutic gastroscope can be difficult, because of the reach of the endoscope, loop formation in the stomach, and flexibility of the gastroscope. The use of a colonoscope may overcome these problems. Objective: To report our experience with distal duodenal stent placement in 16 patients using a colonoscope. Methods: Multicenter, retrospective series of patients with a malignant obstruction at the level of the distal duodenum and proximal jejunum and treated by stent placement using a colonoscope. Main outcome measurements are technical success, ability to eat, complications, and survival. Results: Stent placement was technically feasible in 93% (15/16) of patients. Food intake improved from a median gastric outlet obstruction scoring system (GOOSS) score of 1 (no oral intake) to 3 (soft solids) (p = 0.001). Severe complications were not observed. One patient had persistent obstructive symptoms presumably due to motility problems. Recurrent obstructive symptoms were caused by tissue/tumor ingrowth through the stent mesh [n = 6 (38%)] and stent occlusion by debris [n = 1 (6%)]. Reinterventions included additional stent placement [n = 5 (31%)], gastrojejunostomy [n = 2 (12%)], and endoscopic stent cleansing [n = 1 (6%)]. Median survival was 153 days. Conclusion: Duodenal stent placement can effectively and safely be performed using a colonoscope in patients with an obstruction at the level of the distal duodenum or proximal jejunum. A colonoscope has the advantage that it is long enough and offers good endoscopic stiffness, which avoids looping in the stomach

How Work Impairments and Reduced Work Ability are Associated with Health Care Use in Workers with Musculoskeletal Disorders, Cardiovascular Disorders or Mental Disorders

__Abstract__ Purpose the aim of this study was to explore how work impairments and work ability are associated with health care use by workers with musculoskeletal disorders (MSD), cardiovascular disorders (CVD), or mental disorders (MD). Methods in this cross-sectional study, subjects with MSD (n = 2,074), CVD (n = 714), and MD (n = 443) were selected among health care workers in 12 Dutch organizations. Using an online questionnaire, data were collected on in