Broad emission lines from opaque electron-scattering environment of SN 1998S

I propose that broad narrow-topped emission lines with full width at zero intensity >20000 km/s, seen in early-time spectra of SN 1998S, originate from a dense circumstellar gas and not from the supernova ejecta. The tremendous line width is the result of multiple scattering of the narrow line radiation on thermal electrons of the circumstellar shell with the Thomson optical depth of about 4 on 1998 March 6.Comment: 7 pages, 4 figures, accepted for publication in MNRA

Exact soliton solution and inelastic two-soliton collision in spin chain driven by a time-dependent magnetic field

We investigate dynamics of exact N-soliton trains in spin chain driven by a time-dependent magnetic field by means of an inverse scattering transformation. The one-soliton solution indicates obviously the spin precession around the magnetic field and periodic shape-variation induced by the time varying field as well. In terms of the general soliton solutions N-soliton interaction and particularly various two-soliton collisions are analyzed. The inelastic collision by which we mean the soliton shape change before and after collision appears generally due to the time varying field. We, moreover, show that complete inelastic collisions can be achieved by adjusting spectrum and field parameters. This may lead a potential technique of shape control of soliton.Comment: 5 pages, 5 figure

The origin of the high velocity circumstellar gas around SN 1998S

Modelling of high resolution Balmer line profiles in the early-time spectra of SN 1998S shows that the inferred fast (roughly 400 km/s) circumstellar (CS) gas on days 23 and 42 post-explosion is confined to a narrow, negative velocity gradient shell just above the photosphere. This gas may be identified with a slow (v < 40 km/s) progenitor wind accelerated at the ejecta-wind interface. In this scenario, the photosphere coincides with a cool dense shell formed in the reverse shock. Acceleration by radiation from the supernova or by a shock-accelerated relativistic particle precursor are both possible explanations for the observed fast CS gas. An alternative, equally plausible scenario is that the fast CS gas is accelerated within shocked clouds engulfed by the outer shock, as it propagates through the intercloud wind.Comment: 9 pages, 6 figures. MNRAS, accepted. Typos added, acknowledgments correcte

Stringent homology-based prediction of H. sapiens-M. tuberculosis H37Rv protein-protein interactions

10.1186/1745-6150-9-5Biology Direct91

Temperature-induced resonances and Landau damping of collective modes in Bose-Einstein condensed gases in spherical traps

Interaction between collective monopole oscillations of a trapped Bose-Einstein condensate and thermal excitations is investigated by means of perturbation theory. We assume spherical symmetry to calculate the matrix elements by solving the linearized Gross-Pitaevskii equations. We use them to study the resonances of the condensate induced by temperature when an external perturbation of the trapping frequency is applied and to calculate the Landau damping of the oscillations.Comment: revtex, 9 pages, 5 figure

Approach to the semiconductor cavity QED in high-Q regimes with q-deformed boson

The high density Frenkel exciton which interacts with a single mode microcavity field is dealed with in the framework of the q-deformed boson. It is shown that the q-defomation of bosonic commutation relations is satisfied naturally by the exciton operators when the low density limit is deviated. An analytical expression of the physical spectrum for the exciton is given by using of the dressed states of the cavity field and the exciton. We also give the numerical study and compare the theoretical results with the experimental resultsComment: 6 pages, 2 figure

An impact evaluation of technology adoption by smallholders in Sichuan, China: The case of sweet potato-pig systems

We employ propensity score matching (PSM) framework to examine the impact of sweet potatobased feed technology adoption on household-based pig production in Sichuan, China. An ex post survey in six villages was conducted in 2009, of which five villages were in project intervention sites (exposed area) and one village in the same township but not exposed to project intervention (nonexposed area). We randomly selected 111 households in the exposed areas from the list of households previously interviewed in a baseline survey and 53 households from non-exposed area. Matching estimators such as nearest neighbor matching (NNM), radius matching (RM) and kernel matching (KM) were used to estimate average treatment effects. Results indicate positive net benefit from adoption of sweet potato-based feeding technology, i.e., gross margin estimates of silage adopters are on average higher by 2-4 RMB per kg liveweight of output than non-adopters of similar characteristics. Silage adopters are also likely to produce 3-7 more slaughter pigs per year than non-adopters having similar characteristics, on average. Analysis of factors driving adoption indicates that sweet potato-based feed technology is not suitable in all smallholder context in Sichuan. Where this is suitable is in systems where sweet potato is an important crop, where there is limited access to input markets such as in upland or mountainous areas, where corn is not an important crop, and where households raise no more than 10 pigs given available household labor for pig raising in rural areas (generally either old people who are no longer active in the labor force, or young children who are still in school). Overall, the results show that sweet potato-based feed technology plays an important role in helping household-based pig producers become resilient, by having options in feeding strategies that help them cope with volatility in output prices (e.g., prices of live pigs as a function of retail prices of pork) and input prices (e.g., price of corn vis-à-vis price of pork, price of industrial feed). Exposure to the technology and its benefits through actual demonstration also appears to be more effective in engendering uptake and sustaining adoption

A spatial-state-based omni-directional collision warning system for intelligent vehicles

Collision warning systems (CWSs) have been recognized as effective tools in preventing vehicle collisions. Existing systems mainly provide safety warnings based on single-directional approaches, such as rear-end, lateral, and forward collision warnings. Such systems cannot provide omni-directorial enhancements on driver’s perception. Meanwhile, due to the unclear and overlapped activation areas of above single-directional CWSs, multiple kinds of warnings may be triggered mistakenly for a collision. The multi-triggering may confuse drivers about the position of dangerous targets. To this end, this paper develops a spatial-state-based omni-directional collision warning system (S-OCWS), aiming to help drivers identify the specific danger by providing the unique warning. First, the operational domains of rear-end, lateral, and forward collisions are theoretically distinguished. This distinction is attained by a geometric approach with a rigorous mathematical derivation, based on the spatial states and the relative motion states of itself and the target vehicle in real time. Then, a theoretical omni-directional collision warning model is established using time-to-collision (TTC) to clarify activation conditions for different collision warnings. Finally, the effectiveness of the S-OCWS is validated in field tests. Results indicate that the S-OCWS can help drivers quickly and properly respond to the warnings without compromising their control over lateral offsets. In particular, the probability of drivers giving proper responses to FCW doubles when the S-OCWS is on, compared to when the system is off. In addition, the S-OCWS shortens the responses time of nonprofessional drivers, and therefore enhances their safety in driving

Local recurrences in western low rectal cancer patients treated with or without lateral lymph node dissection after neoadjuvant (chemo) radiotherapy: An international multi-centre comparative study

Background: In the West, low rectal cancer patients with abnormal lateral lymph nodes (LLNs) are commonly treated with neoadjuvant (chemo)radiotherapy (nCRT) followed by total mesorectal excision (TME). Additionally, some perform a lateral lymph node dissection (LLND). To date, no comparative data (nCRT vs. nCRT + LLND) are available in Western patients. Methods: An international multi-centre cohort study was conducted at six centres from the Netherlands, US and Australia. Patients with low rectal cancers from the Netherlands and Australia with abnormal LLNs (≥5 mm short-axis in the obturator, internal iliac, external iliac and/or common iliac basin) who underwent nCRT and TME (LLND-group) were compared to similarly staged patients from the US who underwent a LLND in addition to nCRT and TME (LLND + group). Results: LLND + patients (n = 44) were younger with higher ASA-classifications and ypN-stages compared to LLND-patients (n = 115). LLND + patients had larger median LLNs short-axes and received more adjuvant chemotherapy (100 vs. 30%; p < 0.0001). Between groups, the local recurrence rate (LRR) was 3% for LLND + vs. 11% for LLND- (p = 0.13). Disease-free survival (DFS, p = 0.94) and overall survival (OS, p = 0.42) were similar. On multivariable analysis, LLND was an independent significant factor for local recurrences (p = 0.01). Sub-analysis of patients who underwent long-course nCRT and had adjuvant chemotherapy (LLND-n = 30, LLND + n = 44) demonstrated a lower LRR for LLND + patients (3% vs. 16% for LLND-; p = 0.04). DFS (p = 0.10) and OS (p = 0.11) were similar between groups. Conclusion: A LLND in addition to nCRT may improve loco-regional control in Western patients with low rectal cancer and abnormal LLNs. Larger studies in Western patients are required to evaluate its contribution