Ultrasonic communication in frogs

Among vertebrates, only microchiropteran bats, cetaceans and some rodents are known to produce and detect ultrasounds (frequencies greater than 20 kHz) for the purpose of communication and/or echolocation, suggesting that this capacity might be restricted to mammals. Amphibians, reptiles and most birds generally have limited hearing capacity, with the ability to detect and produce sounds below approximately 12 kHz. Here we report evidence of ultrasonic communication in an amphibian, the concave-eared torrent frog (Amolops tormotus) from Huangshan Hot Springs, China. Males of A. tormotus produce diverse bird-like melodic calls with pronounced frequency modulations that often contain spectral energy in the ultrasonic range. To determine whether A. tormotus communicates using ultrasound to avoid masking by the wideband background noise of local fast-flowing streams, or whether the ultrasound is simply a by-product of the sound-production mechanism, we conducted acoustic playback experiments in the frogs' natural habitat. We found that the audible as well as the ultrasonic components of an A. tormotus call can evoke male vocal responses. Electrophysiological recordings from the auditory midbrain confirmed the ultrasonic hearing capacity of these frogs and that of a sympatric species facing similar environmental constraints. This extraordinary upward extension into the ultrasonic range of both the harmonic content of the advertisement calls and the frog's hearing sensitivity is likely to have co-evolved in response to the intense, predominantly low-frequency ambient noise from local streams. Because amphibians are a distinct evolutionary lineage from microchiropterans and cetaceans (which have evolved ultrasonic hearing to minimize congestion in the frequency bands used for sound communication and to increase hunting efficacy in darkness), ultrasonic perception in these animals represents a new example of independent evolution.     

Study on the accuracy of comprehensive evaluating method based on fuzzy set theory

1.INTRODUCTION Thecomplexinformationsystemsprojectsdevelopers andmanagersneedfeedbackonthequalityofwork productstocontrolprojectactivitiesandtoimprove productquality.Itisnecessarythatappropriateeval uatingmethodsbeusedincomplexinformationsys temsevaluation.Accordingtothedatawecollected,theevaluat ingmethodshadbeendevelopedinthelastforty years[1].Agoodmanynewmethodshaveappeared,suchascomprehensivegrading,expertsdiscussion,cost benefitanalysis,analytichierarchyprocess,data envelopmentanalys…     

Fair Resource Allocation in Networks with Coexisting Unicast and Multirate Multicast Flows

To maximize the aggregate user utility in networks with both multirate multicast and unicast traffic, a unified convex program formulation of the problem is used to integrate multicast and unicast sessions into a common framework, which also takes into account the heterogeneity of multicast receivers. By applying a penalty function approach, a heuristic rate control algorithm is derived. In the distributed implementation of the algorithm in IP networks, core routers employ Random Early Detection (RED) to mark packets in the case of congestion; end-users analyze congestion feedback information and update their rates to calculated optimal values. With an appropriate choice of utility functions and parameters, multicast and unicast sessions can share network resources in the proportional fair manner. Simulation results prove the algorithm‘ s effectiveness. Study is also done on the effect of bandwidth discretization density upon resource allocation fairness in a layered multicast scenario.     

Effects of TiC on the microstructure and formation of acicular ferrite in ferritic stainless steel

The formation mechanism of acicular ferrite and its microstructural characteristics in 430 ferrite stainless steel with TiC additions were studied by theory and experiment. Using an "edge-to-edge matching" model, a 5.25 mismatch between TiC (FCC structure) and ferritic stainless steel (BCC structure) was identified, which met the mismatch requirement for the heterogeneous nucleation of 430 ferritic stainless steel. TiC was found to be an effective nucleation site for the formation of acicular ferrite in a smelting experiment, as analyzed by metallographic examination, Image-Pro Plus 6.0 analysis software, and SEM-EDS. Furthermore, small inclusions in the size of 2-4 μm increased the probability of acicular ferrite nucleation, and the secondary acicular ferrite would grow sympathetically from the initial acicular ferrite to produce multi-dimensional acicular ferrites. Moreover, the addition of TiC can increase the average microstrain and dislocation density of 430 ferrite stainless steel, as calculated by Williamson-Hall (WH) method, which could play some role in strengthening the dislocation.     

LES investigation of swirl intensity effect on unconfined turbulent swirling premixed flame

A finite reaction rate model is presented as a closure of large eddy simulation （LES） to numerically study an open premixed methane/air swirling flame. The resultant model is firstly validated by comparing with reported data and then employed to investigate the effect of swirling intensity on flow field, flame characteristics and combustion instability of the swirling flame. Three differ- ent swirl numbers are considered. The LES results show that as swirling intensity increases, the vortex entrainment and micro-mixing are enhanced, leading to more lean equivalent ratios at flame front; consequently, higher swirling number causes lower flame temperatures and slower CO oxidization; for all simulated swirl numbers, flame fronts are completely located out of the recirculation zones and anchored at the inner surface of the annular swirling steams; swirl number has a crucial effect on swirling flame extension toward radial and tangential dimensions and then significantly affects streamwise flame length, which is a great influencing factor on combustion instability; vortex-induced disturbance on flame in streamwise plays a critical role in combustion instability.     

Review of galactic and extragalactic searches for class I methanol masers

Class I methanol masers are important tools for investigations of star formation throughout the Universe. Recently, a series of surveys for class I methanol masers at the 95 GHz transition toward samples of young stellar objects have been undertaken. These surveys have resulted in the detection of about 200 new class I methanol masers and combined with previous increased the number of known observations they have class I methanol masers in our Galaxy to ~400. From analysis of the relationship between class I methanol maser emission and associated astrophysical objects, it has been shown that the intensity of the class I methanol maser emission is closely correlated with the properties of the 1.1 mm Bolocam Galactic Plane Survey （BGPS） dust continuum sources and outflow properties. This further supports the hypothesis that class I methanol masers are collisionally pumped and excited in shocked regions. Based on these observations, it can be inferred that the BGPS catalog is likely to provide more reliable samples for targeting further class I methanol maser searches. A new survey for class I methanol masers toward a larger size sample of BGPS sources to test this is currently underway. The prospects for detecting class I methanol megamasers in extragalactic sources is discussed, and observations constituting the first sensitive search have been proposed.     

Scalable manufacturing methodologies for improving adeno-associated virus-based pharmaprojects

Adeno-associated virus （AAV） is a promising viral vector and meets most requirements of being a safe biological agent. However, the commercialization of AAV has been hampered due to the limitation of large-scale production, and only a small number of clinical trials have been launched. In recent years, progresses in scalable manufacturing of AAV have dramatically improved AAV- based clinical researches, and have assisted the develop- ment of investigational drug products. An AAVl-based investigational product, Glybera, has been formally approved by European Commission for the treatment of lipoprotein lipase deficiency （LPLD）. Glybera was the first gene therapy product in the western world, and the pro- duction process involves a scalable baculovirus-insect cell system. However, many problems still need to be solved to improve the productivity and quality of AAV. The present review gives critical insights into current state-of-the-art scalable producing methodologies of AAV, such as bacu-lovirus-insect cell system, HSV complementation system, and Ad complementation system, along with a discussion on the problems, solutions, and developmental trends.Novel AAV-producing platforms in Saccharomyces cere- visiae and vaccinia virus complementation system will also be discussed.     

Computational diffusion kinetics and its applications in study and design of rare metallic materials

Computational diffusion kinetics(CDK),with a spirit of and being coupled with the computational thermodynamics(CT,or called as the CALPHAD technique),plays increasingly important role in the alloy design/optimization and microstructure control during the processing of advanced metallic materials.This paper is to highlight recent progress of CDK in research with great focus on novel Ti and Zr alloys,which was largely performed in the authors’group.It ends with one representative example of the applications of CDK,coupled with CT,quantitative phase field,and three-dimensional(3D)statistical calculation,in designing the heattreatment schedule for the dual phase(αβ)Ti–6Al–4V alloys.     

The loop effects on the chargino decays ～χ±1→～χ0 1ff ′in the MSSM

The lighter chargino three body decays ～χ±1→～χ0 1ff ′ via the W^± boson and the charged Higgs boson H^± were studied in the R-parity conserved Minimal Supersymmetric Standard Model （MSSM）. We treat ～χ±1 decays as production and decay of W^± and H^± i.e.,～χ±1→～χ01W^±（H^±） → χ0 1ff ′. Both higgsino- like and wino-like ～χ±1 decays were well investigated. These decays are calculated at 1-loop level and the loop corrections are found to be less than three percent. The signal of the charged Higgs H^± production from ～χ±1 decays is discussed. It will offer important information about the chargino and neutralino sector, as well as the charged Higgs sector in the MSSM.