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In pig production, reducing production costs and improving immunity are important. Grape pomace, a good agricultural by-product, has been thrown away as food waste for a long time. Recently, we found that it could be used as a new source of pig feed. We investigated the effect of grape pomace on inflammation, gut barrier function, meat quality, and growth performance in finishing pigs. Our results indicated that treatment samples showed a significant decrease in water loss, IL-1β, DAO, ROS, and MDA content (p p p Treponema and Streptococcus (p

Under the background of "mass entrepreneurship and innovation", mass entrepreneurship and innovation education urgently need integration with professional education. This paper takes the Network Engineering course of the Technical College for the Deaf of Tianjin University of Technology as an example, analyzes the mass entrepreneurship education's research status, deeply studies the integration education of innovation and entrepreneurship education and the deaf network engineering professional course, and proposes the education path of "integration of expertise and innovation," it gives a new method for the organic combination of entrepreneurship and innovation education and professional education in China's higher special education.

Among the existing clustering algorithms, the k-Means algorithm is one of the most commonly used clustering methods. As an extension of the k-Means algorithm, the k-Modes algorithm has been widely applied to categorical data clustering by replacing means with modes. However, there are more mixed-type data containing categorical, ordinal and numerical attributes. Mixed-type data clustering problem has recently attracted much attention from the data mining research community, but most of them fail to notice the ordinal attributes and establish explicit metric similarity of ordinal attributes. In this paper, the limitations of some existing dissimilarity measure of k-Modes algorithm in mixed ordinal and nominal data are analyzed by using some illustrative examples. Based on the idea of mining ordinal information of ordinal attribute, a new dissimilarity measure for the k-Modes algorithm to cluster this type of data is proposed. The distinct characteristic of the new dissimilarity measure is to take account of the ordinal information of ordinal attribute. A convergence study and time complexity of the k-Modes algorithm based on this new dissimilarity measure indicates that it can be effectively used for large data sets. The results of comparative experiments on nine real data sets from UCI show the effectiveness of the new dissimilarity measure.

The deaf students' classroom attention in higher education is an important factor affecting the acquisition of deaf students' classroom knowledge. This paper studies the deaf students' attention, combines with the measures taken by institutions of higher learning at home and abroad to improve the deaf students' attention, analyzes the main factors affecting the deaf students' classroom attention, builds the mechanism of improving the deaf students' classroom attention by unintentional attention, intentional attention and external environment, forms a three-in-one education mode, improves the deaf students' classroom attention mechanism, and optimizes the deaf students' teaching quality.

In order to solve the problem of low accuracy of key action capture and feature recognition in Chinese sign language human-computer interaction, a large scale continuous sign language data set is established with Kinect equipment. By combining extension analysis theory with immune neural network (INN), extension immune detector is designed to locate the key actions of the sign language effectively. Hu invariant moment feature and Hamming rule are combined to improve immune neural network for accurate sign language image matching. The experimental results show that the sign language key motion capture and recognition accuracy based on extension immune neural network has greater advantages than the classical immune algorithm.

To compared the quality of life and factors affecting the re-employment and non-employment of retirees, suggestions were provided for re-employment and provide for the aged. 450 retirees between 50 and 70 years of age in Xi’an city were surveyed and interviewed semi-structured by means of self-made general situation questionnaire, SF-12 scale and social support revalued scale, and the results were statistically analyzed. There was a strong willingness of retirees to re-enter the workforce, 298 (66 %) of the 450 people were willing to re-enter the workforce and 167(37 %) were re-employed; the quality of life and social support scores of those who have been re-employed are higher than those of those who have not been re-employed (t=-5.595, p

Winter squash (Cucurbita maxima Duch.) and pumpkin (Cucurbita moschata Duch. ex Poir.) are widely consumed in the world. Empirical evidences showed that their cooked texture was related to the starch content and probably starch properties. In this study, starches were extracted from 2 winter squash cultivars (Yinli and Heili) and 1 pumpkin cultivar (Miben) popularly cultivated in China. The mature fruits of three cultivars contained 1.05–6.47% (fresh weight) starch with different granule sizes (d (0.5) 9.51–15.18 μm). Starches from winter squash and pumpkin had polyhedral and spherical shape granules with amylose content varied from 21.35% to 30.17%. All starches exhibited B-type crystalline structure. The relative crystallinity ranged from 26.15% to 31.31%, and the IR absorbance ratios of 1022/995 cm−1 and 1045/1022 cm−1 ranged from 0.759 to 0.806 and from 0.565 to 0.607, respectively, among 3 cultivars. SAXS pattern indicated 9.59–9.80 nm DBragg for these starches. The Mw was highest (5.03 × 107 g/mol) in Miben starch but lowest (3.64 × 107 g/mol) in Heili starch. All starches had identical amylopectin branch chain distributions but varied in average chain length and fb1 and fb2 chains. The gelatinization temperature (To, Tp, Tc) and enthalpy change (ΔH) were lowest in Heili starch and highest in Miben starch. The peak, trough, final and setback viscosities varied from 4468 to 6266 cP, 3116 to 4259.5 cP, 4075 to 6073 cP, and 787 to 1813 cP, respectively. All starch granules showed strong resistance to enzymatic hydrolysis. Yinli and Miben starches had higher RS content in starch pastes and retrograded gels than Heili starch.

We investigate the energy sources of random turbulent motions of ionised gas from H$\alpha$ emission in eight local star-forming galaxies from the Sydney-AAO Multi-object Integral field spectrograph (SAMI) Galaxy Survey. These galaxies satisfy strict pure star-forming selection criteria to avoid contamination from active galactic nuclei (AGN) or strong shocks/outflows. Using the relatively high spatial and spectral resolution of SAMI, we find that -- on sub-kpc scales our galaxies display a flat distribution of ionised gas velocity dispersion as a function of star formation rate (SFR) surface density. A major fraction of our SAMI galaxies shows higher velocity dispersion than predictions by feedback-driven models, especially at the low SFR surface density end. Our results suggest that additional sources beyond star formation feedback contribute to driving random motions of the interstellar medium (ISM) in star-forming galaxies. We speculate that gravity, galactic shear, and/or magnetorotational instability (MRI) may be additional driving sources of turbulence in these galaxies., Comment: 11 pages, 5 figures, 3 tables. Accepted by MNRAS

We investigate how HII region temperature structure assumptions affect "direct-method" spatially-resolved metallicity observations using multispecies auroral lines in a galaxy from the SAMI Galaxy Survey. SAMI609396B, at redshift $z=0.018$, is a low-mass galaxy in a minor merger with intense star formation, analogous to conditions at high redshifts. We use three methods to derive direct metallicities and compare with strong-line diagnostics. The spatial metallicity trends show significant differences among the three direct methods. Our first method is based on the commonly used electron temperature $T_e$([OIII]) from the [OIII]$\lambda$4363 auroral line and a traditional $T_e$([OII]) -- $T_e$([OIII]) calibration. The second method applies a recent empirical correction to the O$^+$ abundance from the [OIII]/[OII] strong-line ratio. The third method infers the $T_e$([OII]) from the [SII]$\lambda\lambda$4069,76 auroral lines. The first method favours a positive metallicity gradient along SAMI609396B, whereas the second and third methods yield flattened gradients. Strong-line diagnostics produce mostly flat gradients, albeit with unquantified contamination from shocked regions. We conclude that overlooked assumptions about the internal temperature structure of HII regions in the direct method can lead to large discrepancies in metallicity gradient studies. Our detailed analysis of SAMI609396B underlines that high-accuracy metallicity gradient measurements require a wide array of emission lines and improved spatial resolutions in order to properly constrain excitation sources, physical conditions, and temperature structures of the emitting gas. Integral-field spectroscopic studies with future facilities such as JWST/NIRSpec and ground-based ELTs will be crucial in minimising systematic effects on measured gradients in distant galaxies., Comment: 21 pages, 14 figures, Accepted for Publication in MNRAS

We report J-band MOSFIRE spectroscopy of a low-mass (log$(M_*/M_\odot)=8.62^{+0.10}_{-0.06}$) star-forming galaxy at $z=0.997$ showing the detection of [NII] and [SII] alongside a strong H$\alpha$ line. We derive a gas-phase metallicity of log$(\text{O}/\text{H})=7.99^{+0.13}_{-0.23}$, placing this object in a region of $M_* - Z$ space that is sparsely populated at this redshift. Furthermore, many existing metallicity measurements in this $M_* - z$ regime are derived from only [NII]/H$\alpha$ (N2), a diagnostic widely used in high-redshift metallicity studies despite the known strong degeneracy with the ionization parameter and resulting large systematic uncertainty. We demonstrate that even in a regime where [NII] and [SII] are at the detection limit and the measurement uncertainty associated with the [NII]/[SII] ratio is high (S/N~3), the more sophisticated Dopita et al. diagnostic provides an improved constraint compared to N2 by reducing the systematic uncertainty due to the ionization parameter. This approach does not, however, dispel uncertainty associated with stochastic or systematic variations in the nitrogen-to-oxygen abundance ratio. While this approach improves upon N2, future progress in extending metallicity studies into this low-mass regime will require larger samples to allow for stochastic variations, as well as careful consideration of the global trends among dwarf galaxies in all physical parameters, not just metallicity., Comment: 11 pages, 3 figures

Sign language is the primary way of communication between deaf people, but the majority of hearing people do not know how to sign. The reliance of deaf people on interpreters is both inconvenient and cost inefficient. Many research groups have experimented with using machine learning to develop automatic translators. Largely, these efforts have been constrained to restrictive dictionaries or insufficiently small signers or signed content. We introduce the world’s largest sign language dataset to date- a collection of 50,000 video snippets taken from a pool of 10,000 unique utterances signed by 50 signers. We further propose several sequence-to-sequence deep learning approaches to automatically translate from Chinese sign language to both English and Mandarin written text. These methods utilize body joint position, facial expression, as well as finger articulation. While models can overfit on training sets, generalization to unforeseen utterances remains challenging with real-world data. The introduced dataset and methods demonstrate how modern machine learning methods are able to close the communication gap between deaf and hearing people.

One important result from recent large integral field spectrograph (IFS) surveys is that the intrinsic velocity dispersion of galaxies traced by star-forming gas increases with redshift. Massive, rotation-dominated discs are already in place at z~2, but they are dynamically hotter than spiral galaxies in the local Universe. Although several plausible mechanisms for this elevated velocity dispersion (e.g. star formation feedback, elevated gas supply, or more frequent galaxy interactions) have been proposed, the fundamental driver of the velocity dispersion enhancement at high redshift remains unclear. We investigate the origin of this kinematic evolution using a suite of cosmological simulations from the FIRE (Feedback In Realistic Environments) project. Although IFS surveys generally cover a wider range of stellar masses than in these simulations, the simulated galaxies show trends between intrinsic velocity dispersion, SFR, and redshift in agreement with observations. In both the observed and simulated galaxies, intrinsic velocity dispersion is positively correlated with SFR. Intrinsic velocity dispersion increases with redshift out to z~1 and then flattens beyond that. In the FIRE simulations, intrinsic velocity dispersion can vary significantly on timescales of, 15 pages, 10 figures; Submitted to MNRAS

The ZFIRE survey has spectroscopically confirmed two proto-clusters using the MOSFIRE instrument on Keck 1: one at z=2.095 in COSMOS and another at z=1.62 in UDS. Here we use an updated ZFIRE dataset to derive the properties of ionized gas regions of proto-cluster galaxies by extracting fluxes from emission lines H$\beta$ 4861\AA, [OIII] 5007\AA, H$\alpha$ 6563\AA, [NII] 6585\AA, and [SII] 6716,6731\AA. We measure gas-phase metallicity of members in both proto-clusters using two indicators, including a strong-line indicator relatively independent of ionization parameter and electron density. Proto-cluster and field galaxies in both UDS and COSMOS lie on the same Mass-Metallicity Relation with both metallicity indicators. We compare our results to recent IllustrisTNG results, which reports no significant gas-phase metallicity offset between proto-cluster and field galaxies until z=1.5. This is in agreement with our observed metallicities, where no offset is measured between proto-cluster and field populations. We measure tentative evidence from stacked spectra that UDS high mass proto-cluster and field galaxies have differing [OIII]/H$\beta$ ratios, however these results are dependent on the sample size of the high mass stacks., Comment: 18 pages, 6 figures, accepted by the Astrophysical Journal

We present gas and stellar kinematics of a high-resolution zoom-in cosmological chemodynamical simulation, which fortuitously captures the formation and evolution of a star-forming barred spiral galaxy, from redshift $z\sim3$ to $z\sim2$ at the peak of the cosmic star formation rate. The galaxy disc grows by accreting gas and substructures from the environment. The spiral pattern becomes fully organised when the gas settles from a thick (with vertical dispersion $\sigma_{v} >$ 50 km/s) to a thin ($\sigma_{v} \sim 25$ km/s) disc component in less than 1 Gyr. Our simulated disc galaxy also has a central X-shaped bar, the seed of which formed by the assembly of dense gas-rich clumps by $z \sim 3$. The star formation activity in the galaxy mainly happens in the bulge and in several clumps along the spiral arms at all redshifts, with the clumps increasing in number and size as the simulation approaches $z=2$. We find that stellar populations with decreasing age are concentrated towards lower galactic latitudes, being more supported by rotation, and having also lower velocity dispersion; furthermore, the stellar populations on the thin disc are the youngest and have the highest average metallicities. The pattern of the spiral arms rotates like a solid body with a constant angular velocity as a function of radius, which is much lower than the angular velocity of the stars and gas on the thin disc; moreover, the angular velocity of the spiral arms steadily increases as function of time, always keeping its radial profile constant. The origin of our spiral arms is also discussed., Comment: Accepted for publication in MNRAS

The global star formation rates (SFR) of galaxies at fixed stellar masses increase with redshift and are known to vary with environment unto z~2. We explore here whether the changes in the star formation rates can also apply to the electron densities of the inter-stellar medium (ISM) by measuring the [OII] (3727A/3729A) ratio for cluster and field galaxies at z~2. We measure a median electron density of ne = 366+/-84 cm-3 for six galaxies (with 1-sigma scatter = 163 cm-3) in the UDS proton-cluster at z=1.62. We find that the median electron density of galaxies in the UDS photo-cluster environment is three times higher compared to the median electron density of field galaxies (ne = 113+/- 63 cm-3 and 1-sigma scatter = 79 cm-3) at comparable redshifts, stellar mass and SFR. However, we note that a sample of six photo-cluster galaxies is insufficient to reliably measure the electron density in the average porto-cluster environment at z~2. We conclude that the electron density increases with redshift in both cluster and field environments up to z~2 (ne = 30 +/- 1 cm-3 for z ~ 0 to ne =254+/- 76 cm-3 for z~1.5). We find tentative evidence (~2.6 sigma ) for a possible dependence of electron density on environment, but the results require confirmation with larger sample sizes., 18 Pages, 6 figures, 3 tables, Accepted for publication in Astrophysical Journal

We present adaptive optics-assisted integral field spectroscopy around the Hα or Hβ lines of 12 gravitationally lensed galaxies obtained with VLT/SINFONI, Keck/OSIRIS and Gemini/NIFS. We combine these data with previous observations and investigate the dynamics and star formation properties of 17 lensed galaxies at 1 < z < 4. Thanks to gravitational magnification of 1.4–90 times by foreground clusters, effective spatial resolutions of 40–700 pc are achieved. The magnification also allows us to probe lower star formation rates (SFRs) and stellar masses than unlensed samples; our target galaxies feature dust-corrected SFRs derived from Hα or Hβ emission of ∼0.8–40 M⊙ yr−1, and stellar masses M* ∼ 4 × 108–6 × 1010 M⊙. All of the galaxies show velocity gradients, with 59 per cent consistent with being rotating discs and a likely merger fraction of 29 per cent, with the remaining 12 per cent classed as ‘undetermined’. We extract 50 star-forming clumps with sizes in the range 60 pc–1 kpc from the Hα (or Hβ) maps, and find that their surface brightnesses, Σclump and their characteristic luminosities, L0, evolve to higher luminosities with redshift. We show that this evolution can be described by fragmentation on larger scales in gas-rich discs, and is likely to be driven by evolving gas fractions.

We use the IllustrisTNG simulations to investigate the evolution of the mass-metallicity relation (MZR) for star-forming cluster galaxies as a function of the formation history of their cluster host. The simulations predict an enhancement in the gas-phase metallicities of star-forming cluster galaxies (10^9< M_star, 5 pages, 4 figures, accepted for publication in MNRAS Letters

In the early Universe finding massive galaxies that have stopped forming stars present an observational challenge as their rest-frame ultraviolet emission is negligible and they can only be reliably identified by extremely deep near-infrared surveys. These have revealed the presence of massive, quiescent early-type galaxies appearing in the universe as early as z$\sim$2, an epoch 3 Gyr after the Big Bang. Their age and formation processes have now been explained by an improved generation of galaxy formation models where they form rapidly at z$\sim$3-4, consistent with the typical masses and ages derived from their observations. Deeper surveys have now reported evidence for populations of massive, quiescent galaxies at even higher redshifts and earlier times, however the evidence for their existence, and redshift, has relied entirely on coarsely sampled photometry. These early massive, quiescent galaxies are not predicted by the latest generation of theoretical models. Here, we report the spectroscopic confirmation of one of these galaxies at redshift z=3.717 with a stellar mass of 1.7$\times$10$^{11}$ M$_\odot$ whose absorption line spectrum shows no current star-formation and which has a derived age of nearly half the age of the Universe at this redshift. The observations demonstrates that the galaxy must have quickly formed the majority of its stars within the first billion years of cosmic history in an extreme and short starburst. This ancestral event is similar to those starting to be found by sub-mm wavelength surveys pointing to a possible connection between these two populations. Early formation of such massive systems is likely to require significant revisions to our picture of early galaxy assembly., Comment: 6 pages, 7 figures. This is the final preprint corresponding closely to the published version. Uploaded 6 months after publication in accordance with Nature policy

We investigate the fraction of starbursts, starburst-AGN composites, Seyferts, and LINERs as a function of infrared luminosity (L_IR) and merger progress for ~500 infrared-selected galaxies. Using the new optical classifications afforded by the extremely large data set of the Sloan Digital Sky Survey, we find that the fraction of LINERs in IR-selected samples is rare ( 10^12 L_odot), starburst-AGN composite galaxies dominate at early--intermediate stages of the merger, and AGN galaxies dominate during the final merger stages. Our results are consistent with models for IR-luminous galaxies where mergers of gas-rich spirals fuel both starburst and AGN, and where the AGN becomes increasingly dominant during the final merger stages of the most luminous infrared objects.

We present the rest-frame optical spectrum of a strongly lensed galaxy at redshift z =1.7 behind the cluster Abell 1689. We detect the temperature sensitive auroral line [O III] 4363, which allows the first direct metallicity measurement for galaxies at z > 1. Our high signal-to-noise spectrum indicates that the target is an extremely low metallicity star-forming galaxy.We estimate an intrinsic absolute B band magnitude of M_{B}=-18.3 \pm 0.1$, with a stellar mass of 4.4$\pm1.2\times10^{8}$ M$_{\odot}$. This galaxy extends the luminosity-metallicity relation of star-forming galaxies at z > 2 by more than an order of magnitude. Given the double-nuclei like morphology and velocity profile of \ha, we tentatively suggest that it could be a merger or a proto-rotating disk galaxy., published version in ApJ Letters. 4 pages, 4 figure, 1 table. References updated

We report the detection of 10 new X-ray filaments using the data from the {\sl Chandra} X-ray satellite for the inner $6^{\prime}$ ($\sim 15$ parsec) around the Galactic center (GC). All these X-ray filaments are characterized by non-thermal energy spectra, and most of them have point-like features at their heads that point inward. Fitted with the simple absorbed power-law model, the measured X-ray flux from an individual filament in the 2-10 keV band is $\sim 2.8\times10^{-14}$ to $10^{-13}$ ergs cm$^{-2}$ s$^{-1}$ and the absorption-corrected X-ray luminosity is $\sim 10^{32}-10^{33}$ ergs s$^{-1}$ at a presumed distance of 8 kpc to the GC. We speculate the origin(s) of these filaments by morphologies and by comparing their X-ray images with the corresponding radio and infrared images. On the basis of combined information available, we suspect that these X-ray filaments might be pulsar wind nebulae (PWNe) associated with pulsars of age $10^3 \sim 3\times 10^5$ yr. The fact that most of the filament tails point outward may further suggest a high velocity wind blowing away form the GC.

We present the first observation of cluster-scale radial metallicity gradients from star-forming galaxies. We use the DEIMOS spectrograph on the Keck II telescope to observe two CLASH clusters at z~0.35: MACS1115+0129 and RXJ1532+3021. Based on our measured interstellar medium (ISM) properties of star-forming galaxies out to a radius of 2.5 Mpc from the cluster centre, we find that the galaxy metallicity decreases as a function of projected cluster-centric distance (-0.15+/-0.08 dex/Mpc) in MACS1115+01. On the mass-metallicity relation (MZR), star-forming galaxies in MACS1115+01 are offset to higher metallicity (~0.2 dex) than the local SDSS galaxies at a fixed mass range. In contrast, the MZR of RXJ1532+30 is consistent with the local comparison sample. RXJ1532+30 exhibits a bimodal radial metallicity distribution, with one branch showing a similar negative gradient as MACS1115+01 (-0.14+/-0.05 dex/Mpc) and the other branch showing a positive radial gradient. The positive gradient branch in RXJ1532+30 is likely caused by either interloper galaxies or an in-plane merger, indicating that cluster-scale abundance gradients probe cluster substructures and thus the dynamical state of a cluster. Most strikingly, we discover that neither the radial metallicity gradient nor the offset from the MZR is driven by the stellar mass. We compare our observations with Rhapsody-G cosmological hydrodynamical zoom-in simulations of relaxed galaxy clusters and find that the simulated galaxy cluster also exhibits a negative abundance gradient, albeit with a shallower slope (-0.04+/-0.03 dex/Mpc). Our observations suggest that the negative radial gradient originates from ram-pressure stripping and/or strangulation processes in the cluster environments., Comment: 17 pages, 11 Figures; Accepted for publication in ApJ

Glucose oxidase (GOD, EC.1.1.3.4) specifically catalyzes the reaction of β-d-glucose to gluconic acid and hydrogen peroxide in the presence of oxygen, which has become widely used in the food industry, gluconic acid production and the feed industry. However, the poor thermostability of the current commercial GOD is a key limiting factor preventing its widespread application. In the present study, amino acids closely related to the thermostability of glucose oxidase from Penicillium notatum were predicted with a computer-aided molecular simulation analysis, and mutant libraries were established following a saturation mutagenesis strategy. Two mutants with significantly improved thermostabilities, S100A and D408W, were subsequently obtained. Their protein denaturing temperatures were enhanced by about 4.4 °C and 1.2 °C, respectively, compared with the wild-type enzyme. Treated at 55 °C for 3 h, the residual activities of the mutants were greater than 72%, while that of the wild-type enzyme was only 20%. The half-lives of S100A and D408W were 5.13- and 4.41-fold greater, respectively, than that of the wild-type enzyme at the same temperature. This work provides novel and efficient approaches for enhancing the thermostability of GOD by reducing the protein free unfolding energy or increasing the interaction of amino acids with the coenzyme.

We investigate the environmental dependence of the mass-metallicity relation at z=2 with MOSFIRE/Keck as part of the ZFIRE survey. Here, we present the chemical abundance of a Virgo-like progenitor at z=2.095 that has an established red sequence. We identified 43 cluster ($=2.095\pm0.004$) and 74 field galaxies ($=2.195\pm0.083$) for which we can measure metallicities. For the first time, we show that there is no discernible difference between the mass-metallicity relation of field and cluster galaxies to within 0.02dex. Both our field and cluster galaxy mass-metallicity relations are consistent with recent field galaxy studies at z~2. We present hydrodynamical simulations for which we derive mass-metallicity relations for field and cluster galaxies. We find at most a 0.1dex offset towards more metal-rich simulated cluster galaxies. Our results from both simulations and observations are suggestive that environmental effects, if present, are small and are secondary to the ongoing inflow and outflow processes that are governed by galaxy halo mass., Comment: 5 pages, 3 figures; accepted for publication in ApJ Letters

We report an integral-field spectroscopic (IFS) observation of a gravitationally lensed spiral galaxy A1689B11 at redshift $z=2.54$. It is the most ancient spiral galaxy discovered to date and the second kinematically confirmed spiral at $z\gtrsim2$. Thanks to gravitational lensing, this is also by far the deepest IFS observation with the highest spatial resolution ($\sim$ 400 pc) on a spiral galaxy at a cosmic time when the Hubble sequence is about to emerge. After correcting for a lensing magnification of 7.2 $\pm$ 0.8, this primitive spiral disk has an intrinsic star formation rate of 22 $\pm$ 2 $M_{\odot}$ yr$^{-1}$, a stellar mass of 10$^{9.8 \pm 0.3}$$M_{\odot}$ and a half-light radius of $r_{1/2}=2.6 \pm 0.7$ kpc, typical of a main-sequence star-forming (SF) galaxy at $z\sim2$. However, the H\alpha\ kinematics show a surprisingly tranquil velocity field with an ordered rotation ($V_{\rm c}$ = 200 $\pm$ 12 km/s) and uniformly small velocity dispersions ($V_{\rm \sigma, mean}$ = 23 $\pm$ 4 km/s and $V_{\rm \sigma, outer-disk}$ = 15 $\pm$ 2 km/s). The low gas velocity dispersion is similar to local spiral galaxies and is consistent with the classic density wave theory where spiral arms form in dynamically cold and thin disks. We speculate that A1689B11 belongs to a population of rare spiral galaxies at $z\gtrsim2$ that mark the formation epoch of thin disks. Future observations with JWST will greatly increase the sample of these rare galaxies and unveil the earliest onset of spiral arms., Comment: 18 pages, 13 figures, 1 table; accepted for publication in ApJ

This paper proposes a new routing protocol, namely Optimal Routing in Multi-sink Sensor Networks based on Fuzzy Comprehensive Evaluation (ORFCE). The protocol applies fuzzy comprehensive evaluation with selecting optimal routing in multi-sink sensor networks by considering three factors, the least residual energy in path, the least average link quality in path, and hop counts from sensor to sink. ORFCE is a multi-path, hierarchical, active and on-demand mixed, and QoS-guaranteed distributed routing protocol. By means of simulating in OMNeT++, the application of the ORFCE protocol will prolong the network lifetime enormously, enhance the packet delivery ratio greatly, and reduce the number of control messages largely.

Recent research shows that the node energy in WSNs can be significantly saved by integrating mobile BS into the network, which is capable of collecting data from sensor nodes. However, the mobile BS may aggravate the latency problem of the network, and thus hinder its use. Rendezvous points are a subset of nodes that buffer data from other sensor nodes, and transfer the buffered data to mobile BS. The locations that the mobile BS must arrive in order to collect all the data from the WSN are called the stop points. Reduction in the number of stop points can serve as a balance between network energy saving and network latency. In this paper, we propose a stop points reducing algorithm, which can get the smallest stop point set in sensor networks while guarantees the coverage of the entire network. The algorithm is verified by extensive experiments.

We spectroscopically survey the galaxy cluster XMM-LSS J02182-05102 (hereafter IRC 0218) using LRIS (optical) and MOSFIRE (near-infrared) on Keck I as part of the ZFIRE survey. IRC 0218 has a narrow redshift range of 1.612 < z(spec) < 1.635 defined by 33 members of which 20 are at R-proj < 1 Mpc. The cluster redshift and velocity dispersion are z(cl) = 1.6233 +/- 0.0003 and sigma(c1) = 254 +/- 50 km s(-1). We reach NIR line sensitivities of similar to 0.3 x 10(-17) erg s(-1) cm(-2) that, combined with multi-wavelength photometry, provide extinction-corrected H alpha star formation rates (SFR), gas phase metallicities from [N II]/H alpha, and stellar masses. We measure an integrated H alpha SFR of similar to 325 M-circle dot yr(-1) (26 members; R-proj < 2 Mpc) and show that the elevated star formation in the cluster core (R-proj < 0.25 Mpc) is driven by the concentration of star-forming members, but the average SFR per H alpha-detected galaxy is half that of members at R-proj similar to 1 Mpc. However, we do not detect any environmental imprint when comparing attenuation and gas phase metallicities: the cluster galaxies show similar trends with M-star as to the field, e.g., more massive galaxies have larger stellar attenuation. IRC 0218's gas phase metallicity-M-star, relation (MZR) is offset to lower metallicities relative to z similar to 0 and has a slope of 0.13 +/- 0.10. Comparing the MZR in IRC 0218 to the COSMOS cluster at z = 2.1 shows no evolution (Delta t similar to 1 Gyr): the MZR for both galaxy clusters are remarkably consistent with each other and virtually identical to several field surveys at z similar to 2.

The classification of galaxy mergers and isolated disks is key for understanding the relative importance of galaxy interactions and secular evolution during the assembly of galaxies. The kinematic properties of galaxies as traced by emission lines have been used to suggest the existence of a significant population of high-z star-forming galaxies consistent with isolated rotating disks. However, recent studies have cautioned that post-coalescence mergers may also display disk-like kinematics. To further investigate the robustness of merger/disk classifications based on kinematic properties, we carry out a systematic classification of 24 local (U)LIRGs spanning a range of galaxy morphologies: from isolated spiral galaxies, ongoing interacting systems, to fully merged remnants. We artificially redshift the WiFeS observations of these local (U)LIRGs to z=1.5 to make a realistic comparison with observations at high-z, and also to ensure that all galaxies have the same spatial sampling of ~900 pc. Using both kinemetry-based and visual classifications, we find that the reliability of kinematic classification shows a strong trend with the interaction stage of galaxies. Mergers with two nuclei and tidal tails have the most distinct kinematic properties compared to isolated disks, whereas a significant population of the interacting disks and merger remnants are indistinguishable from isolated disks. The high fraction of late-stage mergers showing disk-like kinematics reflects the complexity of the dynamics during galaxy interactions. However, the exact fractions of misidentified disks and mergers depend on the definition of kinematic asymmetries and the classification threshold when using kinemetry-based classifications. Our results suggest that additional indicators such as morphologies traced by stars or molecular gas are required to further constrain the merger/disk classifications at high-z., Comment: 16 pages, 5 figures, ApJ accepted

We present the spectroscopic confirmation of a galaxy cluster at $z=2.095$ in the COSMOS field. This galaxy cluster was first reported in the ZFOURGE survey as harboring evolved massive galaxies using photometric redshifts derived with deep near-infrared (NIR) medium-band filters. We obtain medium resolution ($R \sim$ 3600) NIR spectroscopy with MOSFIRE on the Keck 1 telescope and secure 180 redshifts in a $12'\times12'$ region. We find a prominent spike of 57 galaxies at $z=2.095$ corresponding to the galaxy cluster. The cluster velocity dispersion is measured to be $\sigma_{\rm v1D}$ = 552 $\pm$ 52 km/s. This is the first study of a galaxy cluster in this redshift range ($z \gt 2.0$) with the combination of spectral resolution ($\sim$26 km/s) and the number of confirmed members (${>}50$) needed to impose a meaningful constraint on the cluster velocity dispersion and map its members over a large field of view. Our $\Lambda$CDM cosmological simulation suggests that this cluster will most likely evolve into a Virgo-like cluster with ${\rm M_{vir}}{=}10^{14.4\pm0.3} {\rm M_\odot}$ ($68\%$ confidence) at $z\sim$ 0. The theoretical expectation of finding such a cluster is $\sim$ $4\%$. Our results demonstrate the feasibility of studying galaxy clusters at $z > 2$ in the same detailed manner using multi-object NIR spectrographs as has been done in the optical in lower redshift clusters., Comment: 6 pages, 5 figures; accepted for publication in ApJ Letters

We compare a large sample of galaxies between 0.51.5) are consistent with a model in which the ISM conditions are more extreme at high redshift than seen in the global spectra of local galaxies. We speculate that global spectra of our high redshift galaxies may be dominated by HII regions similar to the extreme clumpy, dense star-forming complexes in the Antennae and M82. The transition to local-type conditions occurs between 0.8 1.5). We use our theoretical models to derive a new redshift-dependent classification line that utilizes the standard optical diagnostic line ratios [OIII]/H-beta and [NII]/H-alpha. Our new line can be used to separate star-forming galaxies from AGN between z=0 to z~3.5. We anticipate that our redshift-dependent optical classification line will be useful for future large surveys with near-infrared multi-object spectrographs. We apply our classification line to a sample of gravitationally lensed galaxies at z~2.5. Although limited by small numbers, we show that our classification line is consistent with the position of AGN that have been independently confirmed via other methods., Comment: 7 pages, 3 figures, accepted for publication in the Astrophysical Journal Letters