Av Values Research Articles

Measurement of interstellar extinction for classical T Tauri stars using far-UV H2 line fluxes

Understanding the interstellar and potentially circumstellar extinction in the sight lines of classical T Tauri stars is an important ingredient for constructing reliable spectral energy distributions, which catalyze protoplanetary disk chemistry, for example. Therefore, some attempts of measuring AV toward individual stars have been made using partly different wavelength regimes and different underlying assumptions. We used strong lines of Lyα fluorescent H2 and derived the extinction based on the assumption of optically thin transitions. We investigated a sample of 72 classical T Tauri stars observed with the Hubble Space Telescope in the framework of the ULLYSES program. We computed AV and RV values for the 34 objects with sufficient data quality and an additionally AV value for the canonical RV = 3.1 value. Our results agree largely with values obtained from optical data. Moreover, we confirm the degeneracy between AV and RV and present possibilities to break this. Finally, we discuss whether the assumption of optical thin lines is valid.

Phytochemical, antioxidant, lipid peroxidation inhibition and sensory properties of roasted coffee mixed with various quantities of pomposia fruit (Syzygium cumini L.) powder

PurposeThis study aims to find out how pomposia fruit powder (Syzygium cumini L.) mixed with roasted coffee (RCO) affected antioxidants, phytochemicals, lipid peroxidation inhibition and sensory attributes.Design/methodology/approachPomposia fruits (Syzygium cumini L.) powder (PFP) was integrated with RCO at levels of 0.0%, 5.0%, 10.0%, 15.0% and 20.0%. RCO, PFP and binary mixtures containing RCO: PFP were evaluated for their total phenolics (TP), total flavonoids (TF), anthocyanin content (AC), antioxidant activity and phenolic compounds fractionation. The oxidative indices of coffee oil samples were measured throughout different storage intervals. Additionally, sensory characteristics of RCO enriched with different PFP doses were evaluated.FindingsPFP samples exhibited the greatest TP content (1910 mg/100 g), whereas RCO samples had the lowest concentration (1090 mg/100 g). As more PFP was added, the corresponding coffee blends’ concentrations of TP, TF and AC were improved significantly. PFP possesses a radical-scavenging activity that is about 1.20 times more than RCO’s. DPPH (2,2-diphenyl-1-picrylhydrazyl) radical-scavenging activity jumped significantly from 74.13% in control (untreated) samples to 77.64%, 78.39% and 80.15% for samples enriched with 10.0%, 15.0% and 20% PFP, respectively. Significant increases in gallic acid, hesperidine, benzoic acid, chlorogenic acid, hispertin, catechol, quercetin, pyrogallol and rutin were detected when RCO was mixed with different quantities of PFP. At the end of storage trial, the coffee oil treated with 20% PFP had AV, PV and TBA values that were about 1.70, 1.95 and 1.66 times lower, respectively, than those of the control sample that had not had PFP addition. The RCO with 5.0% PFP achieved the greatest over acceptability grades.Originality/valueTo the best of the authors’ knowledge, this study was the first study to evaluate the effect of incorporating various level of pomposia fruit powder into RCO. The findings shows that adding different concentrations of pomposia fruit powder into RCO can indeed enhance the radical-scavenging activity of the coffee and potentially extend its shelf life.

Analysis of AgNPs@AuNPs/GO’s Impact on Water-Based Drilling Muds and Comparison with Graphane, GO, AuNPs/GO’s Effects: Labs Research

We investigateed the effect of AgNPs@AuNPs/GO on the rheological and filtration properties of sodium-bentonite water based drilling muds (Na-bentonite WBDM) and compared the possible effects of graphene, graphene oxide (GO), and graphene oxide functionalized with gold nanoparticles (AuNPs/GO) on Na-bentonite WBDM. Graphene, AuNPs, AgNPs, GO, AuNPs/GO, and AgNPs@AuNPs/GO were initially synthesized, and subsequently subjected to scanning electron microscopy, tranmission electron microscopy, energy-dispersive X-ray analysis, reflection absoprtion infrared spectroscopy, and X-ray photoelectron spectroscopy characterization. At a rate of 0.0005% to 0.01% (w/v), synthesized and described nanoparticles were added to Na-bentonite WBDM. Rheological and filtration loss analyses of the nanomaterial-containing Na-bentonite WBDM were then performed following American Petroleum Institute Standards. According to the study’s findings, adding graphene and AgNPs/GO to drilling mud at varying rates did not have any influence on PV values when compared to spud mud; however, adding GO and AgNPs@AuNPs/GO had a positive effect of 67% and 33%. Furthermore, the addition of graphene, GO, AuNPs/GO, and AgNPs@AuNPs/GO increased the AV values by 17.6%, 44%, 18.75%, 26%, YP values; by 44.4%, 44%, 30%, 22%, 10 s values; by 55.5%, 33%, 30%, 66.6%, 10 min values; by 30.7%, 43%, 42%, 46%, filtration loss values; by 10%, 9.52%, 8.4%, 3.84%.

Effects of Land uses on Soils Quality in Rwandan Central Plateau Agro-Ecological Zone

Conversion of land use from forest to agricultural uses modifies soil quality through physiochemical soil properties changes. This study was conducted in Rwanda’s central plateau agro-ecological zone to evaluate the effect of forest and agricultural land uses on soil quality. The study was conducted in 2020. Soil samples were collected at the top, middle and bottom positions of each of the two land uses. We analyzed soil bulk density, soil moisture content, soil pH, soil organic matter (SOM), total nitrogen (TN), available phosphorus (Av P), and CEC for each position of the land uses. Data were analyzed using ANOVA in GENSTAT version 13. The results revealed that soil properties were significantly affected by land use change. Analysis of variances (LSD<0.05) results showed, however, that treatments were not significantly different within the same land use. The results showed that treatments from top position of forest lands had the highest mean values for soil organic matter and total N parameters with the respective mean values of 6.58 %, and 0.37 %. Treatments from middle position of forest lands had the highest mean values for soil moisture content and Av P parameters respectively with 23.60 % and 29.56 ppm. But, soil bulk density was high on top position of agricultural land with a mean value of 1.49 g/cm3. Land users are advised to apply crop and soil management techniques which maintain soil quality and productivity on agricultural lands.

Census of Young Stars in Galactic Star Forming Region Sh2-88

We present here the census and characterization of Young Stellar Objects (YSOs) associated with the active star-forming H II region Sh2-88 with multi-wavelength data situated in the Vulpecula OB1 association. To understand the extinction properties of Sh2-88 region, we generate an extinction map over 20×20 arcminutes using the neighbourhood method of Gutermuth et al. (2005) from the deep near-infrared HK band photometric archival data of UKIDSS. We find a sizable variable extinction over the region up to AV ≃11.7 mag, with a median value of AV ≃4.3 mag. The high extinction regions trace the dense filamentary structure, which was found earlier in the far-infrared and sub-mm data. Following the YSO classification scheme of Gutermuth et al. (2009), we have identified 74 YSOs in that region using Spitzer-IRAC data from four mid-infrared bands (3.6, 4.5, 5.8 and 8 μm) and 2MASS near-infrared K-band (2.16 μm) data. Among 74 YSOs, six are class I and 68 class II objects. Using IPHAS Hα, r, and i-band photometry, we have identified 41 additional YSOs. Among these 41, four sources are common with IR excess YSOs. From the spatial distribution of YSOs, it is apparent that YSOs are primarily distributed over the relatively higher extinction regions of the cloud, and star-formation activity might be ongoing in those dense parts of the cloud.

A simple HPLC-MS/MS method for the determination of polymyxin B in human plasma and its application in the pharmacokinetic study in elderly patients infected with multidrug-resistant Gram-negative bacteria.

Introduction: Polymyxin B is widely used to treat infections caused by multidrug-resistant Gram-negative bacteria. However, the pharmacokinetic study data of PB in the elderly are scarce. Herein, a simple method to measure the concentration of PB in human plasma was developed and validated by high performance liquid chromatography-tandem mass spectrometry, and it was applied to a PK study in the elderly. Methods: PB was extracted from human plasma by a rapid protein-precipitation method using 0.1% formic acid in methanol and then separated on an ultimate AQ-C18 column using linear gradient elution with a 0.5-mL/min flow rate. Subsequently, PB was detected using a mass spectrometer operated in positive-ion and multiple-reaction-monitoring modes. Results: The lower limits of quantification of the method for Polymyxin B1 and Polymyxin B2 were 1.00 and 0.10μg/mL, respectively. The linear ranges for PB1 and PB2 were 1.00-20.02 and 0.10-2.04μg/mL, respectively. Patients receiving a 75-mg maintenance dose every 12h had AUCss, 24h, and Css, av values of 117.70 ± 37.03μg h/mL and 4.14 ± 1.74μg/mL, respectively. For patients receiving a 100mg maintenance dose, these values were 152.73 ± 70.09μg h/mL and 5.43 ± 2.85μg/mL, respectively. Conclusion: The validated HPLC-MS/MS method was successfully applied to a study on the pharmacokinetics of PB in elderly patients infected with multidrug-resistant Gram-negative bacteria. Both two dose strategies in this study would have a excessive PB exposure in the elderly patients then the therapeutic window recommended by guidelines.

Volume Backscattering Strength Estimation of Plankton from Water Column Multibeam Echosounder Data at Alor Strait, East Nusa Tenggara, Indonesia

Plankton support marine lives in significant roles as the main food source and ecological functions. However, marine information regarding plankton abundance is scanty and not distributed equally along Indonesian waters. In general, research in plankton abundance were conducted using conventional methods which unable to identify extensively. Hence, the main objective of this study was to estimate the qualitative volume backscattering strength (A ν ) of plankton abundance in the Alor Strait by utilizing multibeam echosounder water column data. Data acquisition was obtained during Jala Citra 3 – “Flores” 2023 expedition held by the Indonesian Navy Hydrographic and Oceanographic Center. The instrument used in this study is the Kongsberg EM302 multibeam echosounder operating at a frequency of 30kHz which acquired both bathymetry and water column data simultaneously. The results show the average value of the volume backscattering strength that varies in the distribution of sample pings at the research site. The largest average Av value is -120.071 dB at sample point 287 which placed in shallow water by the nearest island. Additionally, the smallest value is -142.783 dB at sample point 272 with around 1800 meters depth. It expects the correlation between depth and volume backscatter strength value which can be further investigated.

Optimization of the Heat-Drying Conditions of Drone Pupae by Response Surface Methodology (RSM).

Recent research has been conducted on various types of pre-processing methods for insects, including freeze-drying, microwave drying, hot air heat drying, and non-heat drying. This study aimed to identify the factors that have the greatest impact on heat drying conditions and establish the optimal heat drying conditions for drone pupae (Apis melifera L.) using response surface methodology (RSM) to minimize quality changes. Drone pupae were treated under various conditions, including blanching time (53-187 s) (X1), drying temperatures (41.6-58.4 °C) (X2), and drying time (266-434 min) (X3). The effect of these treatments on response variables, including the color parameter (WI, YI, BI, △E, and BD), AV, and TB of the dried drone pupae, was evaluated using a central composite design. The whole design consisted of 20 experimental points carried out in random order, which included eight factorial points, six center points, and six axial points. The optimal drying conditions for drone pupae were determined to be a blanching time of 58 s, a drying temperature of 56.7 °C, and a drying time of 298 min. The response variables were most affected by drying temperature and drying time and to a lesser extent by blanching time. The processed drone pupae using the optimized drying conditions resulted in the color parameters (WI, BI, YI, ΔE, and BD) being found to be 66.67, 21.33, 26.27, 31.27 and 0.13, respectively. And TB (log CFU/g) and AV (mg/g) values were found to be 3.12 and 4.33, respectively. The estimated and actual values for dried drone pupae showed no significant difference (p < 0.05). Comparing the physicochemical and microbiological properties of freeze-dried and optimal heat-dried drone pupae, the L and b value as well as PV were significantly lower in the heat-dried samples, while no significant difference was observed in the a value and AV (p < 0.05). Our study suggests that the model we developed can be applied to the large-scale production of drying conditions for use in the pharmaceutical and food industries.

Delving deep: A population of extremely dusty dwarfs observed by JWST

Aims. We take advantage of the NIRCam photometric observations available as part of the Cosmic Evolution Early Release Science survey (CEERS) to identify and analyse very red sources in an effort to discover very dusty star forming galaxies. Methods. We select red galaxies as objects with a S/N &gt; 3 at 4.4 μm and a S/N &lt; 2 in all JWST and HST filters at λ ≤ 2 μm, which corresponds to [F200W]−[F444W]&gt; 1.2 considering CEERS depths. This selection is ideal to identify very dusty (AV &gt; 1 mag) galaxies with stellar masses between 106 and 1010 M⊙ at z &lt; 5, more massive dusty galaxies at z = 5 − 18 and galaxies at z &gt; 18 due to the Lyman absorption, independently of their dust extinction. Results. Our sample of F200W-dropouts contains no strong candidates at z &gt; 6.5, instead it consists almost completely (∼81%) of z &lt; 2 low-mass galaxies, with a median stellar mass of 107.3 M⊙. These galaxies show an exceptional dust extinction with median value of AV = 4.9 mag, completely unexpected given their low stellar mass. The remaining galaxies, which are at z &lt; 6.5, show similar large dust extinction (AV &gt; 1), but they are generally more massive &gt; 107.5 M⊙.

Sapaki: Galactic O3If* star possibly born in isolation

Context. The study of high-mass stars found to be isolated in the field of the Milky Way may help to probe the feasibility of the core-accretion mechanism in the case of massive star formation. The existence of truly isolated stars may efficiently probe the possibility that individual massive stars can be born in isolation. Aims. We observed WR67a (hereafter Sapaki), an O3If* star that appears to be isolated close to the center of a well-developed giant cavity that is aptly traced by 8.0 μm hot dust emission. Methods. We acquired medium-resolution (R = 4100) and moderate signal-to-noise (S/N = 95 at 4500 Å) spectra for Sapaki in the range of 3800 − 10 500 Å with the Magellan Echellette (MagE) at Las Campanas Observatory. We computed the line-of-sight total extinctions. Additionally, we restricted its heliocentric distance by using a range of different estimators. Moreover, we measured its radial velocity from several lines in its spectrum. Finally, we analyzed its proper motions from Gaia to examine its possible runaway status. Results. The star has been classified as having the spectral type O3If* given its resemblance to standard examples of the class. In addition, we found that Sapaki is highly obscured, reaching a line-of-sight extinction value of AV = 7.87. We estimated the heliocentric distance to be in the range of d = 4 − 7 kpc. We also estimated its radial velocity to be Vr = −34.2 ± 15.6 km s−1. We may also discard its runaway status solely based on its 2D kinematics. Furthermore, by analyzing proper motions and parallaxes provided by Gaia, we found only one other star with compatible measurements. Conclusions. Given its apparent non-runaway status and the absence of clustering, Sapaki appears to be a solid candidate for isolated high-mass star formation in the Milky Way.

Light and colour of cirrus, translucent, and opaque dust in the high-latitude area of LDN 1642

ABSTRACT We have performed a 5-colour surface photometric study of the high-galactic-latitude area of dark nebula LDN 1642. Scattered light properties are presented of diffuse, translucent, and opaque dust over the range of 3500–5500 Å . Far infrared absolute photometry at 200 µm improves the precision of and provides a zero point to the extinction. The intensity of the scattered light depends on dust column density in a characteristic way: for optically thin dust the intensity first increases linearly, then turns to a saturation value; at still larger extinctions the intensity turns down to a slow decrease. The AV value of the saturated intensity maximum shifts in a systematic way, from AV ≈ 1.5 mag at 3500 Å to ∼3 mag at 5500 Å . The intensity curves offer a straight-forward explanation for the behaviour of the scattered-light colours. At the intensity peak the colour agrees with the integrated starlight colour, while it is bluer at the low- and redder at the high-column-density side of the peak, respectively. These colour changes are a direct consequence of the wavelength dependence of the extinction. We have compared the colours of the LDN 1642 area with other relevant observational studies: high-latitude diffuse/translucent clouds, wide-field cirrus dust; and externally illuminated AGB-star envelopes. For extragalactic low-surface-brightness sources cirrus is an unwanted foreground contaminant. Our results for cirrus colours can help to distinguish cases where a diffuse plume or stream, apparently associated with a galaxy or a group or cluster, is more likely a local cirrus structure.

Nobeyama 45 m CO J = 1–0 observations of luminous type 1 AGNs at z ≈ 0.3

Abstract We have performed CO J = 1–0 observations of 10 galaxies hosting luminous (Lbol &amp;gt; 1046 erg s−1) type 1 active galactic nuclei (AGNs) with the Nobeyama 45 m radio telescope. The targets are selected because they are expected to be rich in molecular gas based on their high nebular dust extinction (AV). However, no significant CO emission lines were detected in any of the targets. The upper limits of the CO J = 1–0 luminosities are lower than expected given the molecular gas mass inferred from the nebular AV. This inconsistency may be due to overestimated AV values due to the lack of stellar absorption correction. Considering more reliable AV values, the CO J = 1–0 non-detections by Nobeyama 45 m are natural. This suggests that our results do not contradict the conversion methods from AV to molecular gas mass proposed in the literature. This survey suggests that careful AV measurements as well as CO observations are still needed to improve the measurements or estimates of the molecular gas content of galaxies hosting luminous AGNs.

On the average horizontal illuminance in rooms with one or two point light sources

ABSTRACT To ensure high-quality lighting in indoor spaces, many objective parameters have been suggested in building codes and standards all over the world. Despite the emergence of luminance-based metrics, the average horizontal illuminance (E av) remains popular in practice. For the case of relatively small rooms with one or two point light sources, it is often intended to determine the point with horizontal illuminance equal to E av. It is also intended to have the computation for various room scenarios, so that the outcome can be predicted using a simple model. This study, therefore, aims to propose a method to identify the location of point of E av on horizontal plane in cuboid rooms with various sizes, with one or two point light sources, and to further verify the theoretical concept. To achieve the objective, scenarios and assumptions are described using mathematical tools, followed with verification using grid computations and Monte Carlo simulation of 10,000 random scenarios. Logarithmic models to predict E av value and its representative location are proposed. The room length-to-width ratio is found more influential, compared to the source luminous intensity characteristics, in affecting the location of point of E av.

MISHEMT’s multiple conduction channels influence on its DC parameters

The Si3N4/ AlGaN/ AlN/ GaN Metal-Insulator-Semiconductor High Electron Mobility Transistor (MISHEMT) analog performance was ascertained considering the device’s multiple channels. MISHEMTs with different gate lengths, source/drain electrodes depths, source/drain distances to the gate electrode and AlGaN aluminum molar fractions were analyzed. The total drain current has 3 different components, where one of them is related to MOS conduction and the other two are related to HEMT conduction. Due to their different transport mechanism and distance to the gate electrode, each channel conduction exhibits different threshold voltages, causing unusual transfer and output characteristics, such as transconductance multiple slopes and a steady output resistance. As a result, the MISHEMTs presents an unexpected increase in intrinsic voltage gain (Av) for high gate bias (strong conduction). The HEMT conduction and the conduction through all the AlGaN volume are responsible for sustaining drain current levels so high that it affects the Early voltage more strongly than the degradation of output conductance, ensuring a high Av values.

Dairy cow hoof impact and slide measurements for common Ontario dairy farm floorings

In the context of understanding lameness and injury from slipping, our objective was to characterize hoof impact and slide of 5 cows walking on 6 flooring surfaces commonly used in Ontario dairy farms: diamond-grooved concrete (DC), sanded epoxy-covered concrete (EC), grooved rubber mat (GR), high-profile rubber mat (HR), low-profile rubber mat (LR), and turf grass (TG; Kentucky bluegrass/fescue mix). Surface hardness was measured on each surface using a Clegg Impact Soil Tester. Five trained lactating Holstein cows were each walked over all 6 surfaces sequentially in a randomized order. Walking speeds were determined from 60-fps videos. A 3-axis accelerometer attached to the lateral claw of each hindfoot captured continuous horizontal (aH), vertical (aV), lateral (aTLat), and medial (aTMed) accelerations at 2,500 Hz during each trial, from which peak values were identified. Data from 45°-rosette strain gauges glued to the dorsal surface of both medial and lateral hooves allowed for the calculation of principal strains (ε1 and ε2). From continuous data, several data points were extracted from 3 to 6 stances/trial: peak values of aH, aV, and aT for the impact phase of the stance; midstance values of ε1 and ε2 as proxies for force on the foot; magnitudes of normal (i.e., consistent and repeatable) sliding on the surface during the support phase; and 3 timing events to capture the cadence of the motion. All aH and aV signals were inspected onscreen to identify irregularities between the end of impact and beginning of breakover that indicated hoof slipping, which was observed on all surfaces. The effects on all measured variables of surface, cow, speed, and hoof (and all significant higher-order factors) were assessed by ANOVA in SAS 9.4 (SAS Institute Inc.), after verifying data normality. Values of aHmax, indicating grip on the surface from highest to lowest, ranked the surfaces in this order: LR, DC, HR, GR, EC, and TG. Ranking on aVmax, indicating most to least cushioning of the hoof on impact, ranked the surfaces in this order: DC, HR, GR, EC, LR, and TG. Differences in ranking among these and other significant impact variables indicate that future studies of lameness on different surfaces need to include all significant variables identified here. We detected no surface and strain interactions in either the ε1 or ε2 strain, indicating that the surfaces do not affect the overall loads on the foot at midstance. Additionally, lateral and medial hooves may have different roles in a stance. The results highlight the capacity to evaluate flooring types with this technology, and the study provides a tool for future work to examine the role of flooring types in the causation of lameness.

Modified atmosphere packaging with chitosan coating to prevent deterioration of fresh in-hull Badami’s pistachio fruit

BackgroundFresh in-hull pistachio fruits are very perishable and hence have a limited storage life, with marketers and customers wishing for a longer shelf life. The present research was performed to explore the combined effects of different packaging conditions (ambient atmospheric condition, and passive- and active-modified atmosphere packaging) as well as chitosan coating (0, 1, and 1.5%w/v) on postharvest quality of fresh in-hull pistachios stored at 5 °C and 85–90% relative humidity for 45 days. The efficacy of treatments in prolongation of pistachio fruit shelf life was evaluated by determining weight loss, kernel firmness, acid (AV) and peroxide values (PV), mold and yeast count, aflatoxin content, and hull color parameters (L*, a*, b*, C*, h°, and BI) at 0, 15, 30 and 45 days of storage. In addition, O2 and CO2 concentrations in MAP headspace were monitored.ResultsBy applying high molecular weight chitosan coatings and MAP conditions, PV and AV values, microbial growth, aflatoxin B1 production, and weight loss values were inhibited, as well as kernel firmness reduction and hull color deterioration during storage were controlled. Active-MAP treatments in most cases performed better than passive-MAP treatments in this regard (P < 0.05). Combining chitosan coating with MAP demonstrated additive synergistic effects. At the end of storage, 1.5% chitosan-coated treatment under active-MAP maintained firmness (87% of the control treatment), hull lightness (76% of the control treatment), and microbial count (similar to the control treatment). It also maintained minimum weight loss (6.39%), acid (0.91 meq O2 kg−1 oil) and peroxide (0.49 goleic acid/100 goil) values compared to other treatments, proving that chitosan coating combined with MAP was more effective in preserving pistachio quality parameters. The equilibrium O2 and CO2 levels of passive-MAP treatments were maintained at higher values than those of active-MAP treatments which indicated that passive-MAP treatments had higher respiration rates than those of active-MAP treatments during storage.ConclusionsThe results revealed that applying the combination technique of MAP and chitosan coating effectively preserved the quality attributes and lengthened the shelf life of fresh in-hull pistachios. Therefore, it could potentially be commercialized as a new approach for future industry application.Graphical

Properties of luminous red supergiant stars in the Magellanic Clouds

Context. There is evidence that some red supergiants (RSGs) experience short-lived phases of extreme mass loss, producing copious amounts of dust. These episodic outburst phases help strip the hydrogen envelope from evolved massive stars, drastically affecting their evolution. However, to date, the observational data of episodic mass loss is limited. Aims. This paper aims to derive surface properties of a spectroscopic sample of 14 dusty sources in the Magellanic Clouds using the Baade telescope. These properties can be used for future spectral energy distribution fitting studies to measure the mass-loss rates from present circumstellar dust expelled from the star through outbursts. Methods. We applied MARCS models to obtain the effective temperature (Teff) and extinction (AV) from the optical TiO bands. We used a χ2 routine to determine the model that best fits the obtained spectra. We computed the Teff using empirical photometric relations and compared this to our modelled Teff. Results. We have identified a new yellow supergiant and spectroscopically confirmed eight new RSGs and one bright giant in the Magellanic Clouds. Additionally, we observed a supergiant B[e] star and find that the spectral type has changed compared to previous classifications, confirming that the spectral type is variable over decades. For the RSGs, we obtained the surface and global properties, as well as the extinction (AV). Conclusions. Our method has picked up eight new, luminous RSGs. Despite selecting dusty RSGs, we find values for AV that are not as high as expected given the circumstellar extinction of these evolved stars. The most remarkable object from the sample, LMC3, is an extremely massive and luminous evolved massive star and may be grouped amongst the largest and most luminous RSGs known in the Large Magellanic Cloud (log(L*/L⊙) ~ 5.5 and R = 1400 R⊙).

Preparation of bioactive peptides from marine industrial waste for moon cake preservation by coating

AbstractIn this study, fish marine bioactive peptides (FMBP) from gill waste obtained from Tilapia (Oreochromis mossambicus) and bighead carp (Hypophthalmichthys nobilis) were explored to provide a green preservation method to maintain the taste and flavor of Chinese moon cake. FMBP were hydrolyzed using a mixture of protease (neutral protease: alkaline protease = 1:1). The enzymatic reaction conditions were researched by single‐factor experiments with antibacterial activity as the evaluation index. Moon cakes were treated with FMBP coating (2.0%, 2.5%, 3.0% or 3.5%) and stored for 25 days at 28°C without packaging. The effect of FMBP on the quality of moon cakes was investigated considering microbiological, physicochemical and sensory properties. Research showed that FMBP significantly inhibited the growth of microorganisms during storage while maintaining the taste of moon cake. The 3% FMBP had the best effect on the coating treatment, which the PV and AV values reduced most significantly (p &lt; 0.05), and especially the total number of colonies (p &lt; 0.05) and the number of coliforms (p &lt; 0.01) was significantly inhibited. The shelf‐life of moon cakes treated with FMBP coating was extended, 2% FMBP by 10 days and 3% or 3.5% FMBP by 20 days, compared with the control group without FMBP treatment by 5 days (when the total number of molds was more than 150 CFU/g, the moon cake was spoiled). These results indicate that FMBP can be used as a food additive antimicrobial agent and preservative.Novelty Impact StatementThe optimal FMBP enzymatic hydrolysis conditions were obtained, which could be used in the field of food additive antimicrobial or preservative agent. FMBP significantly inhibited the growth of microorganisms during storage while maintaining the quality of moon cakes. The 3% FMBP had the best effect on the coating treatment, which the shelf‐life of moon cakes was extended by 20 days.

Understanding star formation in molecular clouds

Probability distribution functions of the total hydrogen column density (N-PDFs) are a valuable tool for distinguishing between the various processes (turbulence, gravity, radiative feedback, magnetic fields) governing the morphological and dynamical structure of the interstellar medium. We present N-PDFs of 29 Galactic regions obtained from Herschel imaging at high angular resolution (18″), covering diffuse and quiescent clouds, and those showing low-, intermediate-, and high-mass star formation (SF), and characterize the cloud structure using the ∆-variance tool. The N-PDFs show a large variety of morphologies. They are all double-log-normal at low column densities, and display one or two power law tails (PLTs) at higher column densities. For diffuse, quiescent, and low-mass SF clouds, we propose that the two log-normals arise from the atomic and molecular phase, respectively. For massive clouds, we suggest that the first log-normal is built up by turbulently mixed H2 and the second one by compressed (via stellar feedback) molecular gas. Nearly all clouds have two PLTs with slopes consistent with self-gravity, where the second one can be flatter or steeper than the first one. A flatter PLT could be caused by stellar feedback or other physical processes that slow down collapse and reduce the flow of mass toward higher densities. The steeper slope could arise if the magnetic field is oriented perpendicular to the LOS column density distribution. The first deviation point (DP), where the N-PDF turns from log-normal into a PLT, shows a clustering around values of a visual extinction of AV (DP1) ~ 2–5. The second DP, which defines the break between the two PLTs, varies strongly. In contrast, the width of the N-PDFs is the most stable parameter, with values of σ between ~0.5 and 0.6. Using the ∆-variance tool, we observe that the AV value, where the slope changes between the first and second PLT, increases with the characteristic size scale in the ∆-variance spectrum. We conclude that at low column densities, atomic and molecular gas is turbulently mixed, while at high column densities, the gas is fully molecular and dominated by self-gravity. The best fitting model N-PDFs of molecular clouds is thus one with log-normal low column density distributions, followed by one or two PLTs.

Analysis of Water Distribution and Muscle Quality of Silver Carp (Hypophthalmichthys molitrix) Chunks Based on Electron-Beam Irradiation.

Electron-beam irradiation (EBI) is an efficient, safe, and nonthermal sterilization technique that is extensively used in food preservation research. Here we report the effects of different EBI doses (0, 4, 8 kGy) and preservation temperatures (room temperature [RT], 4 °C) on the muscle water distribution and muscle quality indices of silver carp chunks (SCCs). The highest entrapped water content was found in the 4-kGy-irradiated/4-°C-stored samples. The expressible moisture content (EMC) of the SCCs increased with increasing irradiation dose and was significantly lower in the RT group than in the 4 °C group. The irradiation dose and preservation temperature had no significant effect on the moisture content, whiteness value and protein content of SCCs (p > 0.05). When the irradiation dose reached 8 kGy, AV value, POV value and TVB value were significantly increased (p < 0.05). The myofibrillar protein content and actomyosin content of the SCCs in the 4 °C group was higher than that of the specimens in the RT group by 0.29–0.98 mg/mL (p < 0.05) and 36.21–296.58 μg/mL (p < 0.05), respectively. Overall, EBI treatment (4 kGy) and low-temperature preservation (4 °C) helped retain the muscle water content of the SCCs and preserve their quality, thereby endorsing the EBI treatment of silver carp products.