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This paper reports on four of the sources observed in the KAGONMA (KAgoshima Galactic Object survey with the Nobeyama 45-m telescope by Mapping in Ammonia lines) project for which mapping observations have been completed (KAG35, KAG45, KAG64, and KAG71). In this study, we compiled the analysis results of four sources for which mapping observations were completed in the KAGONMA project and statistically investigated the range to which star formation activity affects the molecular gas. In order to investigate the affected range, we analyzed the heating range by focusing on the temperature distribution of the molecular cloud and found that it is within about 3 pc. This suggests that direct star formation feedback in molecular clouds is very spatially limited.
The depletion of CO molecules is observed in infrared dark clouds. However, only few exsamples are found in pc-scale. An NH3 emission is one of good counter parts of C18O because of similar effective critical density. Our NH3 observations of a molecular filament associated with CMa OB1 or KAG 71, which is a target of Kagoshima Galactic Object survey with Nobeyama 45-m telescope by Mapping in Ammonia lines (KAGONMA) project. Although NH3 data shows similarity in morphology with infrared data suggesting no depletion, C18O in the clumps 4 and 6 are weaker than expected based on NH3 data. After examining the dissipation of the high-density gas, photodissociation, and depletion, we concluded that CO is depleted at least in the clump 4. It is a new example of depletion in pc-scale.
Blood was drawn from 18 inpatients fullfilling the DSMIII criteria for schizophrenia and their 15 age- and sex-matched clinically infection-free controls before and after neuroleptic treatment. Blood films were stained with MGG solution, mixed, and subsequently read in random order by one observer. The lymphocytes were examined by light microscopy and classified into six types: normal lymphocytes, Downey type I atypical lymphocytes, Downey type III atypical lymphocytes, stress lymphocytes, plasmocytoid lymphocytes, and large granular lymphocytes. Downey type I and III atypical lymphocytes were classified into small, medium, and large lymphocytes. Schizophrenic patients had significantly more Downey type III medium size cells before treatment (p = 0.019 before treatment and p = 0.056 after treatment) and less Downey type I small size cells (p = 0.113 before treatment and p = 0.026 after treatment). Our study supports the idea of a possible subgroup of schizophrenia exhibiting immunological aberrations. In the present study, we found morphologically more specified cells which could be involved in this alteration.
The weakly nonlinear stability analysis of plane Poiseuille flow (PPF) and plane Couette flow (PCF) when viscous dissipation is taken into account is considered. The impermeable lower boundary is considered adiabatic, while the impermeable upper boundary is isothermal. The linear stability of this problem has been performed by Barletta and Nield (J. Fluid Mech., vol. 662, 2010, pp. 475–492) for PCF and by Barletta et al. (J. Fluid Mech., vol. 681, 2011, pp. 499–514) for PPF. These authors found that longitudinal rolls are the preferred mode of convection and the onset of instability is described through the governing parameters $\unicode[STIX]{x1D6EC}=Ge\;Pe^{2}$ and $Pr$, where $Ge$, $Pe$ and $Pr$ are respectively the Gebhart number, the Péclet number and the Prandtl number. The current study focuses on the near-threshold behaviour of longitudinal rolls by using a weakly nonlinear analysis. We determine numerically up to third order the coefficients of the Landau amplitude equation and investigate in detail the influences on bifurcation characteristics of the different nonlinearities present in the system. The results indicate that for both PPF and PCF configurations (i) the inertial terms have no influence on the nonlinear evolution of the disturbance amplitude (ii) the nonlinear thermal advection terms act in favour of pitchfork supercritical bifurcations and (iii) the nonlinearities associated with viscous dissipation promote subcritical bifurcations. The global impact of the different nonlinear contributions indicate that, independently of the Gebhart number, the bifurcation is subcritical if $Pr<0.25$ ($Pr<0.77$) for PPF (PCF). Otherwise, for higher Prandtl number, there exists a particular value of Gebhart number, $Ge^{\ast }$ such that the bifurcation is supercritical (subcritical) if $Ge<Ge^{\ast }$ ($Ge>Ge^{\ast }$). Finally, for both PPF and PCF, the amplitude analysis indicates that, in the supercritical bifurcation regime, the equilibrium amplitude decreases on increasing $Pr$ and a substantial enhancement (reduction) in heat transfer rate is found for small $Pr$ (moderate or large $Pr$).
Identifying the convective/absolute instability nature of a local base flow requires an analysis of its linear impulse response. One must find the appropriate singularity in the eigenvalue problem with complex frequencies and wavenumbers and prove causality. One way to do so is to show that the appropriate integration contour of this response, a steepest decent path through the relevant singularity, exists. Due to the inherent difficulties of such a proof, one often verifies instead whether this singularity satisfies the collision criterion. In other words, one must show that the branches involved in the formation of this singularity come from distinct halves of the complex wavenumber plane. However, this graphical search is computationally intensive in a single plane and essentially prohibitive in two planes. A significant computational cost reduction can be achieved when root finding procedures are applied instead of graphical ones to search for singularities. They focus on locating these points, with causality being verified graphically a posteriori for a small parametric sample size. The use of root-finding procedures require auxiliary equations, often derived by applying the zero group velocity conditions to the dispersion relation. This relation, in turn, is derived by applying matrix forming to the differential eigenvalue problem and taking the determinant of the resulting system of algebraic equations. Taking the derivative of the dispersion relation with respect to the wavenumbers generates the auxiliary equations. If the algebraic system is decoupled, this derivation is straightforward. However, its computational cost is often prohibitive when the algebraic system is coupled. Other methods exist, but often they can also be too costly and/or not reliable for two wavenumber plane searches. This paper describes an alternative methodology based on sensitivity analysis and adjoints that allow the zero group velocity conditions to be applied directly to the differential eigenvalue problem. In doing so, the direct and auxiliary differential eigenvalue problems can be solved simultaneously using standard shooting methods to directly locate singularities. Auxiliary dispersion relations no longer have to be derived, although it is shown that they are the algebraic equivalent of the auxiliary differential eigenvalue problems obtained by this alternative methodology. Using the latter dramatically reduces computational costs. The search for arbitrary singularities is then not only accelerated in single wavenumber planes but it also becomes viable in two wavenumber planes. Finally, the new method also allows group velocity calculations, greatly facilitating the verification of causality. Several test cases are presented to illustrate the capabilities of this new method.
We present a machine learning methodology to separate quasars from galaxies and stars using data from S-PLUS in the Stripe-82 region. In terms of quasar classification, we achieved 95.49% for precision and 95.26% for recall using a Random Forest algorithm. For photometric redshift estimation, we obtained a precision of 6% using k-Nearest Neighbour.
In the collapsing phase of a molecular cloud, the molecular gas temperature is a key to understand the evolutionary process from a dense molecular cloud to stars. In order to know this, mapping observations in NH3 lines are required. Therefore, we made them based on the FUGIN (FOREST Unbiased Galactic plane Imaging survey with Nobeyama 45m telescope). The 6 maps were observed in NH3 (J,K) = (1,1), (2,2), (3,3) and H2O maser lines and obtained temperature maps; some show temperature gradient in a cloud. Additionally 72 cores were observed. These candidates were called as KAGONMA or KAG objects as abbreviation of KAgoshima Galactic Object survey with Nobeyama 45-M telescope in Ammonia lines. We show the results of two regions in W33 and discuss their astrophysical properties.
The purpose of this work is to study the effect of SiO2- and Al2O3-NPs on the microstructure and mechanical properties of the weld bead (WB) created by a process of Submerged Arc Welding (SAW) between two AISI 1025 steel plates. Also it was necessary consider the chemical compositions of slags and burned fluxes, in order to determine the elements that are deposited and contribute in the final microstructure of WB. The welding materials to form each WB were a M12K electrode, a commercial fused flux (CFF) and AISI 1025 steel plates bevelled at 45°. In addition SiO2- or Al2O3-NPs an ethylic alcohol mixture were applied directly to the beveled surfaces, just before the SAW process, which was carried out according to the AWS A5.17 norm. Microstructural and phase changes at the Heat Affected Zone (HAZ) and Welding Zone (WZ) were analysed by metallographic Optical and Scanning Electron Microscopies. The mechanical properties of the WBs were determined through Tensile, Charpy impact and Vickers Hardness tests. By means of metallography of WBs, it was determined that the length of the AF needles increases in 113 and 183 % when adding SiO2- or Al2O3-NPs, respectively. Related to the mechanical properties of the WB, the tensile and yield strength decreases with both additions, SiO2- or Al2O3-NPs. The microhardness at WZ was found to decrease by adding such oxide-NPs. Moreover, the impact energy absorbed by the WBs increases approximately by 83 or 57% due to SiO2- or Al2O3-NPs addition, respectively.
Capillary–gravity waves resonantly excited by an obstacle (Froude number: $Fr=1$) are investigated by the numerical solution of the Euler equations. The radiation of short waves from the long nonlinear waves is observed when the capillary effects are weak (Bond number: $Bo<1/3$). The upstream-advancing solitary wave radiates a short linear wave whose phase velocity is equal to the solitary waves and group velocity is faster than the solitary wave (soliton radiation). Therefore, the short wave is observed upstream of the foremost solitary wave. The downstream cnoidal wave also radiates a short wave which propagates upstream in the depression region between the obstacle and the cnoidal wave. The short wave interacts with the long wave above the obstacle, and generates a second short wave which propagates downstream. These generation processes will be repeated, and the number of wavenumber components in the depression region increases with time to generate a complicated wave pattern. The upstream soliton radiation can be predicted qualitatively by the fifth-order forced Korteweg–de Vries equation, but the equation overestimates the wavelength since it is based on a long-wave approximation. At a large Bond number of $Bo=2/3$, the wave pattern has the rotation symmetry against the pattern at $Bo=0$, and the depression solitary waves propagate downstream.
Coaxially nested intense $E\times B$ sheared flow realized an upgraded stable mirror plasma regime. After such an external control of high vorticity formation due to electron cyclotron heating, significantly unstable plasmas appeared. Thereby, the associated cross-field transport caused a crash of plasmas. Its generalized physics and interpretation could prepare or extend to another possibility of stability in a field-reversed configuration (FRC), for instance. Such underlying physics bases of vorticity formation were essentially or partially performed in tokamaks and stellarators (solved problems). Nevertheless, it remains to be seen whether this mirror-based experimental evidence is applicable or not to open ended FRC devices. This open issue may give a solution of one of unsolved important problems, and possibly provide more generalized and externally controllable opportunities for not only FRC but wider plasma confinement improvements.
The convective and absolute nature of instabilities in Rayleigh–Bénard–Poiseuille (RBP) mixed convection for viscoelastic fluids is examined numerically with a shooting method as well as analytically with a one-mode Galerkin expansion. The viscoelastic fluid is modelled by means of a general constitutive equation that encompasses the Maxwell model and the Oldroyd-B model. In comparison to Newtonian fluids, two more dimensionless parameters are introduced, namely the elasticity number ${\it\lambda}_{1}$ and the ratio ${\it\Gamma}$ between retardation and relaxation times. Temporal stability analysis of the basic state showed that the three-dimensional thermoconvective problem can be Squire-transformed. Therefore, one must distinguish mainly between two principal roll orientations: transverse rolls TRs (rolls with axes perpendicular to the Poiseuille flow direction) and longitudinal rolls LRs (rolls with axes parallel to the Poiseuille flow direction). The critical Rayleigh number for the appearance of LRs is found to be independent of the Reynolds number ($\mathit{Re}$). Depending on ${\it\lambda}_{1}$ and ${\it\Gamma}$, two different regimes can be distinguished. In the weakly elastic regime, the emerging LRs are stationary, while they are oscillatory in the strongly elastic regime. For TRs, it is found that in the weakly elastic regime, the stabilization effect of $\mathit{Re}$ is more important than in Newtonian fluids. Moreover, for sufficiently elastic fluids a jump is observed in the oscillation frequencies and wavenumbers for moderate $\mathit{Re}$. In the strongly elastic regime, the effect of the imposed throughflow is to promote the appearance of the upstream moving TRs for low values of $\mathit{Re}$, which are replaced by downstream moving TRs for higher values of $\mathit{Re}$. Moreover, the results proved that, contrary to the case where $\mathit{Re}=0$, the elasticity number ${\it\lambda}_{1}$ (the ratio ${\it\Gamma}$) has a strongly stabilizing (destabilizing) effect when the throughflow is added. The influence of the rheological parameters on the transition curves from convective to absolute instability in the Reynolds–Rayleigh number plane is also determined. We show that the viscoelastic character of the fluid hastens the transition to absolute instability and even may suppress the convective/absolute transition. Throughout this paper, similarities and differences with the corresponding problem for Newtonian fluids are highlighted.
A feeding station is the area of forage a grazing animal can reach without moving its forefeet. Grazing behavior can be divided into residence within feeding stations (with bites as benefits) and movement between feeding stations (with steps as costs). However, relatively little information has been reported on how grazing animals modify their feeding station behavior seasonally and interannually in response to varying environmental conditions. The feeding station behavior of beef cows (Japanese Black) stocked on a tropical grass pasture (bahiagrass dominant) was monitored for 4 years (2010 to 2013) in order to investigate the association of feeding station behavior with meteorological and sward conditions across the seasons and years. Mean air temperature during stocking often exceeded 30°C during summer months. A severe summer drought in 2013 decreased herbage mass and sward height of the pasture and increased nitrogen concentration of herbage from summer to autumn. A markedly high feeding station number per unit foraging time, low bite numbers per feeding station and a low bite rate were observed in summer 2013 compared with the other seasons and years. Bite number per feeding station was explained by a multiple regression equation, where sward height and dry matter digestibility of herbage had a positive effect, whereas air temperature during stocking had a negative effect (R2=0.658, P<0.01). Feeding station number per minute was negatively correlated with bite number per feeding station (r=–0.838, P<0.001). It was interpreted that cows modified bite number per feeding station in response to the sward and meteorological conditions, and this largely determined the number of feeding stations the animals visited per minute. The results indicate potential value of bite number per feeding station as an indicator of daily intake in grazing animals, and an opportunity for livestock and pasture managers to control feeding station behavior of animals through managements (e.g. fertilizer application, manipulation of stocking intensity and stocking time within the day).
We describe microbiological, clinical and epidemiological aspects of a diphtheria outbreak that occurred in Maranhão, Brazil. The majority of the 27 confirmed cases occurred in partially (n = 16) or completely (n = 10) immunized children (n = 26). Clinical signs and characteristic symptoms of diphtheria such as cervical lymphadenopathy and pseudomembrane formation were absent in 48% and 7% of the cases, respectively. Complications such as paralysis of lower limbs were observed. Three cases resulted in death, two of them in completely immunized children. Microbiological analysis identified the isolates as Corynebacterium diphtheriae biovar intermedius with a predominant PFGE type. Most of them were toxigenic and some showed a decrease in penicillin G susceptibility. In conclusion, diphtheria remains endemic in Brazil. Health professionals need to be aware of the possibility of atypical cases of C. diphtheriae infection, including pharyngitis without pseudomembrane formation.
We investigated the radiocarbon ages and carbon and nitrogen isotope ratios of human skeletal remains from burials at the Yuigahama-minami and Chusei-Shudan-Bochi sites in the Yuigahama area (Kamakura, Japan), which we believe are associated with the great attack on Kamakura by Nitta Yoshisada in AD 1333. The human bones produced enriched δ13C and δ15N values that could be affected by consumption of protein from marine fish and/or mammals with high δ13C and δ15N, and therefore older apparent 14C ages. We thus estimated the marine reservoir effect on human skeletons to determine their true ages. The IsoSource isotope mixing model was employed for reconstructing percentages of marine protein in the human diet, and calibrated calendar dates for the 14C ages were calculated using the marine percentages. At the Yuigahama-minami site, most skeletons from individual burials now date to the last phase of the Kamakura period or the early part of the Muromachi period, while skeletons from mixed human-animal multiple burials date to the latter part of the Kamakura period. The humans from the individual burials, consisting of normal ratios of adult males, could have died a natural death, though the site could also have been used to inter victims of the battle of 1333. The humans from mixed human-animal burials, consisting of a high proportion of infants, were not victims of the 1333 battle, but the site may have been used to inter victims of the Kamakura earthquake in 1293, which resulted in a catastrophic tsunami. On the other hand, the skeletons from multiple burials in the Chusei-Shudan-Bochi site all date to the middle Kamakura period. Coupled with the fact that most humans in the site are male but show no evidence of injuries by sword cuts, it is likely that burials of the Chusei-Shudan-Bochi site could have been a collective interment following the Jinji earthquake in 1241, the Shoka earthquake in 1257, or the Shoka famine in 1258 in the middle Kamakura period. The results of this study indicate that humans from burials in the Yuigahama region were not necessarily victims of the attack by Nitta Yoshisada on Kamakura, but instead were likely victims of natural disasters such as large earthquakes and severe famines, which often occurred in the middle Kamakura period.
Invasive infections caused by Corynebacterium diphtheriae in vaccinated and non-vaccinated individuals have been reported increasingly. In this study we used multilocus sequence typing (MLST) to study genetic relationships between six invasive strains of this bacterium isolated solely in the urban area of Rio de Janeiro, Brazil, during a 10-year period. Of note, all the strains rendered negative results in PCR reactions for the tox gene, and four strains presented an atypical sucrose-fermenting ability. Five strains represented new sequence types. MLST results did not support the hypothesis that invasive (sucrose-positive) strains of C. diphtheriae are part of a single clonal complex. Instead, one of the main findings of the study was that such strains can be normally found in clonal complexes with strains related to non-invasive disease. Comparative analyses with C. diphtheriae isolated in different countries provided further information on the geographical circulation of some sequence types.
Cortical and cancellous bones were demineralized and deproteinized using 1 NHCl and 6% NaOCl, respectively. Experiments were performed at 37°C. The rateconstants were calculated and the structural features of untreated andcompletely demineralized and deproteinized samples were studied by scanningelectron microscopy, showing that intact, contiguous structures wereobtained. For both cases, the rate constant was higher for cancellous bonethan the cortical bone.
We report evidence for graphene layer rearrangements in heavy ion interactions with carbon onions at 140 MeV and 70 MeV per nucleon kinetic energies. Graphene layer rearrangements have been recently predicted in spherical and cylindrical multi-layer graphene systems. The implications of graphene layer rearrangement on the tribological performance of multi-layer nano-carbons in extreme environments are discussed.
Relationships between sward height and short-term ingestive behaviour of cattle were examined for two tropical stoloniferous grasses with contrasting growth forms: centipede grass (Eremochloa ophiuroides (Munro) Hack.; (CG); strongly prostrate) and bahia grass (Paspalum notatum Flügge; (BG); more erect). Turves (500×500 mm) were extracted from field monoculture swards of each grass after the varying duration of re-growth, and presented to animals for a short period (10 bites) to measure bite dimensions (area, depth and volume), bite mass, time per bite and intake rate. In the same re-growth period, CG was always shorter and denser than BG. Bite dimensions, the bite mass and the intake rate of animals increased at a declining rate as the sward height increased for both grasses, showing a tendency for a steeper initial increase, an earlier plateau and a lower maximum in CG than in BG. Due to the difference in the shape of the intake rate response, animals on BG were estimated to require a longer grazing time than those on CG to attain the same daily herbage intake, when the sward is shorter than about 200 mm. The sward height below which the daily intake of animals may be restricted was lower for CG (61–70 mm) than for BG (71–92 mm). The results indicate an advantage of strongly prostrated, highly dense grasses (e.g. CG) over more erect, less dense grasses (e.g. BG) when grazed at a relatively low height (<200 mm). In relation to increasing bite mass, the time per bite pooled over CG and BG was constant until the bite mass reached a critical value (0·55 g dry matter (DM)) and thereafter increased linearly with the bite mass, confirming that cattle are able to perform compound jaw movements that gather herbage into the mouth (manipulative jaw movement) and chew herbage already in the mouth (chewing jaw movement) within one cycle of opening and closing of the jaws.
The evolution of carbon onion structure from spherical to polyhedral is correlated with changes in the sp3/sp2 ratio as a function of increasing synthesis temperature using electron energy loss spectroscopy, scanning electron microscopy, and high resolution electron microscopy. Results that are obtained using asymmetric f-variance versus symmetric Gaussian deconvolution of electron energy loss spectra are compared. The possibility of a separate peak at 287 eV is discussed.
Background and objective: Thiopental has been reported to reduce sympathetic tone, however, it is not clear whether change in heart rate variability is associated with depth of anaesthesia. The purpose of the present study was to evaluate changes in heart rate variability at different depths of hypnosis during induction of anaesthesia with thiopental. Methods: We studied 17 ASA I patients scheduled for minor surgery. The depth of hypnosis was monitored by the BIS. Spectral analysis of heart rate variability using a maximum entropy method resulted in a characteristic power spectrum with two main regions, a high frequency and a low frequency. Haemodynamics, entropy, low frequency, high frequency and low frequency/high frequency were monitored in an awake state and after the induction of anaesthesia. Results: Heart rate increased in a BIS-dependent manner, whereas blood pressure showed no significant changes during the study period. High frequency, entropy and low frequency decreased with a reduction in the BIS value. Low frequency/high frequency showed no significant change during the study period. Conclusions: Induction of anaesthesia with thiopental increased heart rate and decreased high frequency, entropy and low frequency in a BIS-dependent manner, indicating that thiopental reduces cardiac parasympathetic tone depending on the depth of hypnosis.