Compositional analysis of lunar and planetary surfaces using neutron capture gamma rays, 1 January - 31 March 1968

Detection and quantitative determination of hydrogen on planetary and lunar surfaces by neutron capture gamma ray

Short-term immobilization influences use-dependent cortical plasticity and fine motor performance

Short-term immobilization that reduces muscle use for 8-10h is known to influence cortical excitability and motor performance. However, the mechanisms through which this is achieved, and whether these changes can be used to modify cortical plasticity and motor skill learning, are not known. The purpose of this study was to investigate the influence of short-term immobilization on use-dependent cortical plasticity, motor learning and retention. Twenty-one adults were divided into control and immobilized groups, both of which underwent two experimental sessions on consecutive days. Within each session, transcranial magnetic stimulation (TMS) was used to assess motor-evoked potential (MEP) amplitudes, short- (SICI) and long-interval intracortical inhibition (LICI), and intracortical facilitation (ICF) before and after a grooved pegboard task. Prior to the second training session, the immobilized group underwent 8h of left hand immobilization targeting the index finger, while control subjects were allowed normal limb use. Immobilization produced a reduction in MEP amplitudes, but no change in SICI, LICI or ICF. While motor performance improved for both groups in each session, the level of performance was greater 24-h later in control, but not immobilized subjects. Furthermore, training-related MEP facilitation was greater after, compared with before, immobilization. These results indicate that immobilization can modulate use-dependent plasticity and the retention of motor skills. They also suggest that changes in intracortical excitability are unlikely to contribute to the immobilization-induced modification of cortical excitability.George M. Opie, Alexandra Evans, Michael C. Ridding and John G. Semmle

Using NWP to assess the influence of the Arctic atmosphere on mid-latitude weather and climate

The influence of the Arctic atmosphere on Northern Hemisphere mid-latitude tropospheric weather and climate is explored by comparing the skill of two sets of 14-day weather forecast experiments using the ECMWF model with and without relaxation of the Arctic atmosphere towards ERA-Interim reanalysis data during the integration. Two pathways are identified along which the Arctic influences mid-latitude weather: a pronounced one over Asia and Eastern Europe, and a secondary one over North America. In general, linkages are found to be strongest (weakest) during boreal winter (summer) when the amplitude of stationary planetary waves over the Northern Hemisphere is strongest (weakest). No discernible Arctic impact is found over the North Atlantic and North Pacific region, which is consistent with predominantly southwesterly flow. An analysis of the flow-dependence of the linkages shows that anomalous northerly flow conditions increase the Arctic influence on mid-latitude weather over the continents. Specifically, an anomalous northerly flow from the Kara Sea towards West Asia leads to cold surface temperature anomalies not only over West Asia but also over Eastern and Central Europe. Finally, the results of this study are discussed in the light of potential mid-latitude benefits of improved Arctic prediction capabilities

An analytic model for a cooperative ballistic deposition in one dimension

We formulate a model for a cooperative ballistic deposition (CBD) process whereby the incoming particles are correlated with the ones already adsorbed via attractive force. The strength of the correlation is controlled by a tunable parameter $a$ that interpolates the classical car parking problem at $a=0$, the ballistic deposition at $a=1$ and the CBD model at $a>1$. The effects of the correlation in the CBD model are as follows. The jamming coverage $q(a)$ increases with the strength of attraction $a$ due to an ever increasing tendency of cluster formation. The system almost reaches the closest packing structure as $a\to\infty$ but never forms a percolating cluster which is typical to 1D system. In the large $a$ regime, the mean cluster size $k$ increases as $a^{1/2}$. Furthermore, the asymptotic approach towards the closest packing is purely algebraic both with $a$ as $q(\infty)-q(a) \sim a^{-1/2}$ and with $k$ as $q(\infty)-q(k) \sim k^{-1}$ where $q(\infty)\simeq 1$.Comment: 9 pages (in Revtex4), 9 eps figures; Submitted to publicatio

Об анатомическом строении членистостебельного растения Annulina Neuburgiana Radczenko

The purpose was to compare two approaches for the acquisition and analysis of dynamic-contrast-enhanced MRI data with respect to differences in the modelling of the arterial input-function (AIF), the dependency of the model parameters on physiological parameters and their numerical stability. Eight hundred tissue concentration curves were simulated for different combinations of perfusion, permeability, interstitial volume and plasma volume based on two measured AIFs and analysed according to the two commonly used approaches. The transfer constants (Approach 1) K (trans) and (Approach 2) k (ep) were correlated with all tissue parameters. K (trans) showed a stronger dependency on perfusion, and k (ep) on permeability. The volume parameters (Approach 1) v (e) and (Approach 2) A were mainly influenced by the interstitial and plasma volume. Both approaches allow only rough characterisation of tissue microcirculation and microvasculature. Approach 2 seems to be somewhat more robust than 1, mainly due to the different methods of CA administration

Development of a position sensitive X-ray detector for use in a light weight X-ray diffractometer

The characteristics of a curved position sensitive X-ray detector are discussed. Emphasis is placed on the analysis of operation in a focusing diffraction geometry. Problems encountered in constructing the sensor are described. Construction drawings of the sensor components are provided

Development of a position sensitive X-ray detector for use in a light weight X-ray diffractometer

A position sensitive proportional counter for use in an X-ray diffractometer is developed to permit drastic reductions in the power and weight requirements of the X-ray source and the elimination of the power, weight, and complexity of a moving slit. The final detector constructed and tested has a window spanning 138 and a free standing anode curved along an arc of 7.1 cm radius. Demonstration spectra of a quartz sample in a Debye-Sherrer geometry indicate a spatial resolution of 0.4 - 0.5 mm (0.3 - 0.4 theta). The lunar diffractometer consumed 25 watts in the X-ray generator and weighed about 20 pounds

Evidence of Υ(1S)→J/ψ+χc1\Upsilon(1S) \to J/\psi+\chi_{c1} and search for double-charmonium production in Υ(1S)\Upsilon(1S) and Υ(2S)\Upsilon(2S) decays

Using data samples of $102\times10^6$ $\Upsilon(1S)$ and $158\times10^6$ $\Upsilon(2S)$ events collected with the Belle detector, a first experimental search has been made for double-charmonium production in the exclusive decays $\Upsilon(1S,2S)\rightarrow J/\psi(\psi')+X$, where $X=\eta_c$, $\chi_{cJ} (J=~0,~1,~2)$, $\eta_c(2S)$, $X(3940)$, and $X(4160)$. No significant signal is observed in the spectra of the mass recoiling against the reconstructed $J/\psi$ or $\psi'$ except for the evidence of $\chi_{c1}$ production with a significance of $4.6\sigma$ for $\Upsilon(1S)\rightarrow J/\psi+\chi_{c1}$. The measured branching fraction \BR(\Upsilon(1S)\rightarrow J/\psi+\chi_{c1}) is $(3.90\pm1.21(\rm stat.)\pm0.23 (\rm syst.))\times10^{-6}$. The $90\%$ confidence level upper limits on the branching fractions of the other modes having a significance of less than $3\sigma$ are determined. These results are consistent with theoretical calculations using the nonrelativistic QCD factorization approach.Comment: 12 pages, 4 figures, 1 table. The fit range was extended to include X(4160) signal according to referee's suggestions. Other results unchanged. Paper was accepted for publication as a regular article in Physical Review

Study of B^0 -> rho^0 rho^0 decays, implications for the CKM angle phi_2 and search for other B^0 decay modes with a four-pion final state

We present a study of the branching fraction of the decay B^0->rho0rho0 and the fraction of longitudinally polarized rho0 mesons in this decay. The results are obtained from the final data sample containing 772 million BBbar pairs collected at the Y(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. We find 166 +- 59 B^0 -> rho0 rho0 events (including systematic uncertainties), corresponding to a branching fraction of B(B^0->rho0rho0) = (1.02 +- 0.30 (stat) +- 0.15 (syst)) x 10^{-6} with a significance of 3.4 standard deviations and a longitudinal polarization fraction fL = 0.21^{+0.18}_{-0.22} (stat) +- 0.15 (syst). We use the longitudinal polarization fraction to determine the Cabibbo-Kobayashi-Maskawa matrix angle phi_2 = (84.9 +- 13.5) degrees through an isospin analysis in the B->rhorho system. We furthermore find 149 +- 49 B^0->f0rho0 events, corresponding to B(B^0->f0rho0) x B(f0->pi+pi-) = (0.78 +- 0.22 (stat) +- 0.11 (syst)) x 10^{-6}, with a significance of 3.1 standard deviations. We find no other significant contribution with the same final state, and set upper limits at 90% confidence level on the (product) branching fractions, B(B^0->pi+pi-pi+pi-)rho0pi+pi-)<12.0 x 10^{-6}, B(B^0->f0pi+pi-) x B(f0->pi+pi-) f0f0) x B(f0->pi+pi-)^{2} < 0.2 x 10^{-6}.Comment: 21 pages, 20 figures, conference paper for the 2012th CKM workshop, submitted to PR

The mecC-Harboring Region Is a Recombination Hot Spot in Staphylococcus stepanovicii

Introduction Horizontal gene transfer (HGT) is an important driver for resistance- and virulence factor accumulation in pathogenic bacteria such as Staphylococcus aureus. Methods Here, we have investigated the downstream region of the bacterial chromosomal attachment site (attB) for the staphylococcal cassette chromosome mec (SCCmec) element of a commensal mecC- positive Staphylococcus stepanovicii strain (IMT28705; ODD4) with respect to genetic composition and indications of HGT. S. stepanovicii IMT28705 was isolated from a fecal sample of a trapped wild bank vole (Myodes glareolus) during a screening study (National Network on “Rodent-Borne Pathogens”) in Germany. Whole genome sequencing (WGS) of IMT28705 together with the mecC- negative type strain CM7717 was conducted in order to comparatively investigate the genomic region downstream of attB (GenBank accession no. KR732654 and KR732653). Results The bank vole isolate (IMT28705) harbors a mecC gene which shares 99.2% nucleotide (and 98.5% amino acid) sequence identity with mecC of MRSA_LGA251. In addition, the mecC-encoding region harbors the typical blaZ-mecC-mecR1-mecI structure, corresponding with the class E mec complex. While the sequences downstream of attB in both S. stepanovicii isolates (IMT28705 and CM7717) are partitioned by 15 bp direct repeats, further comparison revealed a remarkable low concordance of gene content, indicating a chromosomal “hot spot” for foreign DNA integration and exchange. Conclusion Our data highlight the necessity for further research on transmission routes of resistance encoding factors from the environmental and wildlife resistome