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Hydroxylamine (NH2OH) is a key precursor of both the formation of amino acids and the concurrent synthesis of pyrimidine and purine nucleosides. Recently, NH2OH was detected towards the quiescent molecular cloud G+0.693-0.027, which is located in the Galactic Centre. In this study, we construct the chemical network for NH2OH and its related species via quantum chemical calculations, and simulate their chemistry using the astrochemical code Nautilus in isothermal models and shock models. According to the disagreement distance formula and molecular abundance ratios, we acquire the best-fitting isothermal model T18 and the best-fitting C-shock model S2, respectively. Of these two models, S2 is more suitable for G+0.693-0.027 due to its reproduction of abundances of all considered molecules. From the model, we found that NH2OH and CH3NH2 are mainly formed on grain surfaces, while HNCN and CH2NH, which are the post-shock tracers, are produced by both gas-phase and grain-surface reactions. Our chemical modelling also agrees with the observed abundances or upper limits of NH2OH and its related species towards IRAS 16293-2422 B and Sgr B2(N). Moreover, we predict that NH2OH and the undiscovered species H2NO and HNOH are of high abundance, thus are detectable in cold clouds and pre-stellar cores, and in G+0.693-0.027, respectively.

Aim: Inducible nitric oxide synthase (iNOS) is a validated target for anti-inflammatory treatment. Based on the authors' previous work, novel aza-ursolic acid derivatives were designed and synthesized and their inhibitory activities against lipopolysaccharide (LPS)-induced nitric oxide (NO) release from RAW264.7 cells was evaluated. Materials & results: 16 novel derivatives were screened for their in vitro inhibitory activity against NO release using Griess assays and the cytotoxicity was evaluated using MTT assays. The presence of furoxan joined to the A-ring of ursolic acid and N-methylpiperazine groups in the lead compound was identified for anti-inflammatory activity, and compound 21b showed 94.96% inhibition of NO release at 100 μM with an IC50 value of 8.58 μM. Conclusion: Compound 21b has potential anti-inflammatory activity with low cytotoxicity that warrants further preclinical study and evaluation.

Investigating the physical and chemical structures of massive star-forming regions is critical for understanding the formation and the early evolution of massive stars. We performed a detailed line survey toward six dense cores named as MM1, MM4, MM6, MM7, MM8, and MM11 in G9.62+0.19 star-forming region resolved in ALMA band 3 observations. Toward these cores, about 172 transitions have been identified and attributed to 16 species including organic Oxygen-, Nitrogen-, Sulfur-bearing molecules and their isotopologues. Four dense cores MM7, MM8, MM4, and MM11 are line rich sources. Modeling of these spectral lines reveals the rotational temperature in a range of 72$-$115~K, 100$-$163~K, 102$-$204~K, and 84$-$123~K for the MM7, MM8, MM4, and MM11, respectively. The molecular column densities are 1.6 $\times$ 10$^{15}$ $-$ 9.2 $\times$ 10$^{17}$~cm$^{-2}$ toward the four cores. The cores MM8 and MM4 show chemical difference between Oxygen- and Nitrogen-bearing species, i.e., MM4 is rich in oxygen-bearing molecules while nitrogen-bearing molecules especially vibrationally excited HC$_{3}$N lines are mainly observed in MM8. The distinct initial temperature at accretion phase may lead to this N/O differentiation. Through analyzing column densities and spatial distributions of O-bearing Complex Organic Molecules (COMs), we found that C$_{2}$H$_{5}$OH and CH$_{3}$OCH$_{3}$ might have a common precursor, CH$_{3}$OH. CH$_{3}$OCHO and CH$_{3}$OCH$_{3}$ are likely chemically linked. In addition, the observed variation in HC$_{3}$N and HC$_{5}$N emission may indicate that their different formation mechanism at hot and cold regions., Comment: 40 pages, 23 figures

Dalei Li, Kangwei Mao, Jun Sun, Jiangyang Liu, Chenxi Zhang Department of Pediatric Internal Medicine, The First People’s Hospital of Lianyungang & Xuzhou Medical University Affiliated Hospital of Lianyungang & The First Affiliated Hospital of Kangda College of Nanjing Medical University, Lianyungang, 222061, People’s Republic of ChinaCorrespondence: Kangwei Mao, Department of Pediatric Internal Medicine, The First People’s Hospital of Lianyungang & Xuzhou Medical University Affiliated Hospital of Lianyungang & The First Affiliated Hospital of Kangda College of Nanjing Medical University, No. 6 Zhenhua East Road, Haizhou District, Lianyungang, Jiangsu, 222061, People’s Republic of China, Email maokangwei@163.comBackground: This study aimed to explore the clinical predictors of Alagille syndrome (ALGS) in children and to provide a basis for early diagnosis.Methods: We retrospectively analyzed the clinical data of 14 children diagnosed with ALGS at the First People’s Hospital of Lianyungang City from March 2016 to March 2021 and followed up the children.Results: Among the 14 patients, 9 (64.28%) had cholestasis, 12 (85.71%) had heart malformations, 13 (92.85%) had characteristic facial features, 2 (14.28%) had pruritus, and 2 (14.28%) had a positive family history. Among the 13 patients who were examined by pediatric ophthalmologists, 3 patients had ocular lesions. Among the 13 patients who underwent spine radiography, 2 had typical butterfly vertebrae. Among the 6 patients with hepatic pathology, 2 had intracellular cholestasis, 2 had reduced or no small bile duct in the portal area, 2 had small bile duct hyperplasia with massive fibrous hyperplasia and extensive inflammatory cell infiltration, and 2 underwent biliary tract exploration. Genetic testing of 12 children with ALGS revealed JAG1 gene mutations in 7 cases and NOTCH2 gene mutations in 2 cases. The abovementioned two mutant genes were not detected in any of the 3 cases. Among the 12 followed-up patients, 7 were in stable condition, 5 underwent liver transplantation, and 1 died of severe pneumonia.Conclusion: Cholestatic liver disease, cardiac malformations, and abnormal facial development are predictors of ALGS in children and can be definitively diagnosed by genetic testing.Keywords: Alagille syndrome, cholestasis, genetic testing

Aiming at the problem of bolt looseness in structures, this paper proposes an active control method of axial force monitoring through guided wave and axial force compensation via the inverse piezoelectric effect of a piezoelectric ceramic gasket. Based on the finite element model, the propagation process of guided wave wave in bolted connectors is analyzed, which shows that the transmitted wave energy increases with the increase of bolt clamping force. The analysis of the stress-strain characteristics of the axially polarized and radially polarized piezoelectric ceramic gasket shows that the axially polarized piezoelectric ceramic gasket is more suitable for the control of bolt clamping force. The finite element analysis of the application of piezoelectric ceramic gasket in bolt axial force control shows that the power of guided wave signal increases monotonously with the increase of loaded electric field strength. In accordance with these theoretical methods and research, an active control system for bolt axial force is established in this experiment. The system monitors the power of the guided wave signal in real time and controls the axial force of the bolt by adjusting the intensity of the piezoelectric effect, which achieves an accurate control effect.

To elucidate the effect of tricin in cerebral ischemia/reperfusion (I/R) injury and examine its possible underlying mechanisms. Rats were randomly divided into Sham (exposed the right internal carotid arteries), I/R, and tricin (administered at various doses) groups. After the cerebral I/R injury model was established, a Morris water maze test and a tetrazolium chloride assay were performed. Apoptosis and autophagy were assessed in the nerve cells of hippocampus tissue, and the levels of inflammatory markers within animal serum were detected. Proteins related to apoptosis and the PI3K/Akt pathway were evaluated. To further investigate the mechanisms by which tricin affects brain damage, mouse neuroblastoma cells N2a were divided into control, oxygen-glucose deprivation and reoxygenation (OGD/R), tricin, PI3K/Akt activator, and tricin + PI3K/Akt inhibitor groups. The cell viability, apoptosis, inflammatory factors, and PI3K/Akt pathway related proteins in N2a cells were also detected. The results revealed that I/R-induced learning and memory dysfunction was improved by tricin treatment. The area of cerebral infarction, the levels of apoptosis and autophagy in nerve cells, and the serum inflammatory marker content were all decreased following tricin treatment. Additionally, the expression of Beclin-1 protein was downregulated, while the expression of Bcl-2 protein, p-PI3K/PI3K and p-Akt/Akt was upregulated after tricin treatment. Mechanistically, tricin or PI3K/Akt activator ameliorated OGD/R-induced apoptosis, autophagy, and inflammation. However, these effects were reversed following PI3K/Akt inhibitor treatment in OGD/R-induced N2a cells. In summary, this study suggested that tricin can against I/R-induced brain injury by inhibiting autophagy, apoptosis and inflammation, and activating the PI3K/Akt signaling pathway.

This article reveals the formation mechanism of surface topography and the formation and coupling mechanism of residual stress field (RSF) after abrasive water jet sequential peening (AWJSP) that c...

Water jet peening (WJP) is used to improve the fatigue life of materials by inducing compressive residual stress (RS) into the metal surface. In this paper, the formation mechanism of RS in a single pass WJP process and the coupling mechanism in the multiple passes WJP process are investigated. Then, simulations of single pass WJP are conducted to observe the transient evolution and steady distribution of RS. After that, the influences of process parameters (i.e., the distance between the center of adjacent water jets DC and jet velocity v) on the RS and surface roughness Ra are experimentally and numerically investigated after multiple passes WJP. Besides, the relationship between microhardness and plastic strain is also investigated. Finally, the fatigue performance is evaluated by the tension-tension fatigue tests. Results show that RS is mainly induced by the unrecovered elastic strain resulting from the obstruction of plastic strain. The value of the compressive RS, the depth of the compressive RS layer, and Ra all increase with an increase in v. The distribution of RS and the value of Ra will be affected by DC, the residual stress field (RSF) is uniform, and Ra is minimum for DC = 0.15 mm in this work. Taking RS and Ra into consideration, the optimal process parameters of v = 345 m s−1, DC = 0.15 mm, and jet traverse velocity vf = 4000 mm min−1 are eventually determined. Under this condition, the maximum compressive RS is − 156.7 MPa, the depth of the compressive RS layer is 220 μm, the surface microhardness is 106.7 HV0.1, and the Ra is 0.574 μm. Compared with the original specimens, the fatigue life of the peened specimens and the polished specimens after peening (Ra = 0.382 μm) increased by 53.2% and 90.8%, respectively.

We studied the cloud-cloud collision candidate G323.18+0.15 based on signatures of induced filaments, clumps, and star formation. We used archival molecular spectrum line data from the SEDIGISM 13CO (J = 2−1) survey, from the Mopra southern Galactic plane CO survey, and infrared to radio data from the GLIMPSE, MIPS, Hi-GAL, and SGPS surveys. Our new result shows that the G323.18+0.15 complex is 3.55 kpc away from us and consists of three cloud components, G323.18a, G323.18b, and G323.18c. G323.18b shows a perfect U-shape structure, which can be fully complemented by G323.18a, suggesting a collision between G323.18a and the combined G323.18bc filamentary structure. One dense compressed layer (filament) is formed at the bottom of G323.18b, where we detect a greatly increased velocity dispersion. The bridge with an intermediate velocity in a position-velocity diagram appears between G323.18a and G323.18b, which corresponds to the compressed layer. G323.18a plus G323.18b as a whole are probably not gravitationally bound. This indicates that high-mass star formation in the compressed layer may have been caused by an accidental event. The column density in the compressed layer of about 1.36 × 1022 cm−2 and most of the dense clumps and high-mass stars are located there. The average surface density of class I and class II young stellar objects (YSOs) inside the G323.18+0.15 complex is much higher than the density in the surroundings. The timescale of the collision between G323.18a and G323.18b is 1.59 Myr. This is longer than the typical lifetime of class I YSOs and is comparable to the lifetime of class II YSOs.

To explore the potential function of tricin in diabetic retinopathy (DR) and investigate whether Sestrin2 is closely involved in DR. A single intraperitoneal injection of streptozotocin-induced diabetes model in Sprague-Dawley rats and a high glucose-induced retinal epithelial cell model in ARPE-19 cells were established. The retinas were removed and examined by hematoxylin-eosin (HE) staining and dihydroethidium (DHE) staining. The proliferation ability and reactive oxygen species (ROS) level of ARPE-19 cells were detected by 5-ethynyl-2′-deoxyuridine (EdU) and flow cytometry. Then, the content of superoxide dismutase (SOD), malonaldehyde (MDA), and glutathione peroxidase (GSH-Px) in serum or cell supernatant was tested using enzyme linked immunosorbent assay (ELISA). In addition, the expression of Sestrin2, nuclear factor erythroid-2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), platelet endothelial cell adhesion molecule-1 (CD31), and vascular endothelial growth factor receptor 2 (VEGFR2) in retina tissue or ARPE-19 cells were validated through western blot and immunofluorescence assays. With the increase of MDA and ROS concentration, Sestrin2 expression was downregulated significantly, and Nrf2 and HO-1 expression was also reduced in retina tissue or ARPE-19 cells of model group, whereas CD31 and VEGFR2 expression was upregulated. However, tricin ameliorated the oxidative stress and angiogenesis and rectified the abnormal expression of Sestrin2/Nrf2 in diabetic retinopathy. Further mechanistic studies showed that silence Sestrin2 reduced the protective effect of tricin on ARPE-19 cells, as well as abolished its regulating effect on the Nrf2 pathway. These results suggested that tricin inhibits oxidative stress and angiogenesis in retinal epithelial cells of DR rats via reinforcing Sestrin2/Nrf2 signaling.

We present 850 $��$m polarimetric observations toward the Serpens Main molecular cloud obtained using the POL-2 polarimeter on the James Clerk Maxwell Telescope (JCMT) as part of the B-fields In STar-forming Region Observations (BISTRO) survey. These observations probe the magnetic field morphology of the Serpens Main molecular cloud on about 6000 au scales, which consists of cores and six filaments with different physical properties such as density and star formation activity. Using the histogram of relative orientation (HRO) technique, we find that magnetic fields are parallel to filaments in less dense filamentary structures where $N_{H_2} < 0.93\times 10^{22}$ cm$^{-2}$ (magnetic fields perpendicular to density gradients), while being perpendicular to filaments (magnetic fields parallel to density gradients) in dense filamentary structures with star formation activity. Moreover, applying the HRO technique to denser core regions, we find that magnetic field orientations change to become perpendicular to density gradients again at $N_{H_2} \approx 4.6 \times 10^{22}$ cm$^{-2}$. This can be interpreted as a signature of core formation. At $N_{H_2} \approx 16 \times 10^{22}$ cm$^{-2}$ magnetic fields change back to being parallel to density gradients once again, which can be understood to be due to magnetic fields being dragged in by infalling material. In addition, we estimate the magnetic field strengths of the filaments ($B_{POS} = 60-300~��$G)) using the Davis-Chandrasekhar-Fermi method and discuss whether the filaments are gravitationally unstable based on magnetic field and turbulence energy densities., 18 pages, accepted for publication in ApJ

Background: Cow’s milk protein allergy (CMPA) is an abnormal immune response caused by milk proteins and is most common in infancy and early childhood. Statistics revealed up to 7.5% of children suffered from milk allergy. Its clinical symptoms were characterized by diversity, non-specificity, and can affect multiple systems, including the digestive tract, skin, and respiratory tract. In this study, we aimed to investigate the effects of IL-12, IL-16, and IL-17A on diagnosing and monitoring CMPA in children for clinical treatment. Methods: A total of 158 infants with CMPA and 89 healthy babies were recruited and evaluated. Demographic and clinical information of all participants were recorded. An extensive analysis of inflammatory cytokine levels, including IL-12, IL-16, and IL-17A, was performed in blood samples from 247 infants younger than 9 months. Meanwhile, the serological specificity immunoglobulin E (sIgE) levels were evaluated. In addition, the area under the curve (AUC) values of IL-12, IL-16, and IL-17A in differentiating CMP from healthy babies were measured by receiver operating characteristic analysis. Finally, the correlation between sIgE and IL-12, IL-16, and IL-17A levels were detected using Spearman correlation analysis. Results: Compared with healthy control, infants who developed CMPA had decreased IL-12, increased IL-16, and IL-17A. Moreover, a significant correlation between serum IL-12, IL-16, IL-17A and sIgE levels was observed in the CMPA group. In addition, AUC values of IL-12, IL-16, and IL-17A in discriminating CMPA from healthy infants were 0.8425, 0.9196, and 0.8813, respectively. Finally, IL-12 was increased while IL-16 and IL-17A levels were decreased in the CMPA group after three months of milk avoidance treatment. Conclusions: We found that IL-12, IL-16, and IL-17A levels in children with CMPA were associated with SCORAD scores, sIgE levels, and disease severity, functioning as valuable disease-monitor markers in CMPA.

Tao-Chung Ching et al., We present 850 μm dust polarization observations of the massive DR21 filament from the B-fields In STar-forming Region Observations (BISTRO) survey, using the POL-2 polarimeter and the SCUBA-2 camera on the James Clerk Maxwell Telescope. We detect ordered magnetic fields perpendicular to the parsec-scale ridge of the DR21 main filament. In the subfilaments, the magnetic fields are mainly parallel to the filamentary structures and smoothly connect to the magnetic fields of the main filament. We compare the POL-2 and Planck dust polarization observations to study the magnetic field structures of the DR21 filament on 0.1–10 pc scales. The magnetic fields revealed in the Planck data are well-aligned with those of the POL-2 data, indicating a smooth variation of magnetic fields from large to small scales. The plane-of-sky magnetic field strengths derived from angular dispersion functions of dust polarization are 0.6–1.0 mG in the DR21 filament and ∼0.1 mG in the surrounding ambient gas. The mass-to-flux ratios are found to be magnetically supercritical in the filament and slightly subcritical to nearly critical in the ambient gas. The alignment between column density structures and magnetic fields changes from random alignment in the low-density ambient gas probed by Planck to mostly perpendicular in the high-density main filament probed by James Clerk Maxwell Telescope. The magnetic field structures of the DR21 filament are in agreement with MHD simulations of a strongly magnetized medium, suggesting that magnetic fields play an important role in shaping the DR21 main filament and subfilaments., This work is supported by National Natural Science Foundation of China (NSFC) grant Nos. 11988101, U1931117, 11725313, and 12073061 and the CAS International Partnership Program of Chinese Academy of Sciences grant No. 114A11KYSB20160008. T.-C.C. is funded by Chinese Academy of Sciences Taiwan Young Talent Program grant No. 2018TW2JB0002. T.-C.C. and C.E. were supported by Special Funding for Advanced Users, budgeted and administrated by Center for Astronomical Mega-Science (CAMS), Chinese Academy of Sciences. K.P. is a Royal Society University Research Fellow, supported by grant No. URF\R1\211322. D.J. is supported by the National Research Council of Canada and by a Natural Sciences and Engineering Research Council of Canada (NSERC) Discovery Grant. P.M.K. is supported by the Ministry of Science and Technology (MoST) in Taiwan through grants 109-2112-M-001-022 and 110-2112-M-001-057. C.W.L. is supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (NRF-2019R1A2C1010851), and by the Korea Astronomy and Space Science Institute grant funded by the Korea government (MSIT; Project No. 2022-1-840-05). T.H. is supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) through the Mid-career Research Program (2019R1A2C1087045). W.K. was supported by the NRF grant funded by the MSIT (2021R1F1A1061794). C.E. acknowledges the financial support from grant RJF/2020/000071 as a part of Ramanujan Fellowship awarded by the Science and Engineering Research Board (SERB), Department of Science and Technology (DST), Govt. of India. F.P. acknowledges support from the Spanish State Research Agency (AEI) under grant No. PID2019-105552RB-C43. M.T. is supported by JSPS KAKENHI grant Nos. 18H05442, 15H02063, and 22000005. J.K. is supported by JSPS KAKENHI grant No. 19K14775. L.F. and F.K. acknowledge the support by the MoST in Taiwan through grant 107-2119-M-001-031-MY3 and Academia Sinica through grant AS-IA-106-M03. L.F. acknowledges the support by the MoST in Taiwan through grants 111-2811-M-005-007 and 109-2112-M-005-003-MY3. C.L.H.H. acknowledges the support of the NAOJ Fellowship and JSPS KAKENHI grants 18K13586 and 20K14527. F.K. is supported by the Spanish program Unidad de Excelencia María de Maeztu CEX2020-001058-M, financed by MCIN/AEI/10.13039/501100011033. K.Q. is partially supported by National Key R&D Program of China No. 2022YFA1603100, and acknowledges the National Natural Science Foundation of China (NSFC) grant U1731237. S.P.L. acknowledges grants from the Ministry of Science and Technology of Taiwan 106-2119-M-007-021-MY3 and 109-2112-M-007-010-MY3. Y.D. acknowledges the support of JSPS KAKENHI grants 25247016 and 18H01250. Y.S.D. is supported by the National Key R&D Program of China for grant No. 2022YFA1605300, and NSFC grants Nos. 12273051, 11933003.

Hwang et al., We present and analyze observations of polarized dust emission at 850 μm toward the central 1 × 1 pc hub-filament structure of Monoceros R2 (Mon R2). The data are obtained with SCUBA-2/POL-2 on the James Clerk Maxwell Telescope (JCMT) as part of the B-fields in Star-forming Region Observations survey. The orientations of the magnetic field follow the spiral structure of Mon R2, which are well described by an axisymmetric magnetic field model. We estimate the turbulent component of the magnetic field using the angle difference between our observations and the best-fit model of the underlying large-scale mean magnetic field. This estimate is used to calculate the magnetic field strength using the Davis–Chandrasekhar–Fermi method, for which we also obtain the distribution of volume density and velocity dispersion using a column density map derived from Herschel data and the C18O (J = 3 − 2) data taken with HARP on the JCMT, respectively. We make maps of magnetic field strengths and mass-to-flux ratios, finding that magnetic field strengths vary from 0.02 to 3.64 mG with a mean value of 1.0 ± 0.06 mG, and the mean critical mass-to-flux ratio is 0.47 ± 0.02. Additionally, the mean Alfvén Mach number is 0.35 ± 0.01. This suggests that, in Mon R2, the magnetic fields provide resistance against large-scale gravitational collapse, and the magnetic pressure exceeds the turbulent pressure. We also investigate the properties of each filament in Mon R2. Most of the filaments are aligned along the magnetic field direction and are magnetically subcritical., J.H. is supported by the University of Science and Technology (UST) Overseas Training Program 2022, funded by the University of Science and Technology, Korea (No. 2022-017). K.P. is a Royal Society University Research Fellow, supported by grant number URF\R1\211322. C.W.L. was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (NRF- 2019R1A2C1010851), and by the Korea Astronomy and Space Science Institute grant funded by the Korea government (MSIT; Project No. 2022-1-840-05). D.J. and J.d.F. are supported by the National Research Council of Canada and by Natural Sciences and Engineering Research Council of Canada (NSERC) Discovery Grants. G.P. is supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF; 2020R1A6A3A01100208) W.K. was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT; NRF-2021R1F1A1061794). M.T. is supported by JSPS KAKENHI grant Nos. 18H05442, 15H02063, and 22000005. J.K. is supported by JSPS KAKENHI grant No. 19K14775. M.M. is supported by JSPS KAKENHI grant No. 20K03276. F.P. acknowledges support from the Spanish State Research Agency Agencia Estatal de Investigación (AEI) under grant number PID2019-105552RB-C43. S.P.L., H.Y.D., S.J.L., and M.Z.Y. acknowledge grants from the Ministry of Science and Technology of Taiwan 106-2119-M-007-021-MY3 and 109-2112-M-007-010-MY3. C.E. acknowledges the financial support from grant RJF/2020/000071 as a part of a Ramanujan Fellowship awarded by Science and Engineering Research Board (SERB), Department of Science and Technology (DST), Govt. of India. L.F. and F.K. acknowledge support from the Ministry of Science and Technology of Taiwan, under grant No. MoST107-2119-M-001-031- MY3 and from Academia Sinica under grant No. AS-IA-106-M03. L.F. acknowledges the support by the MoST in Taiwan through grants 111-2811-M-005-007 and 109-2112-M-005-003-MY3. F.K. acknowledges support from the Spanish program Unidad de Excelencia María de Maeztu CEX2020-001058-M, financed by MCIN/AEI/10.13039/501100011033. Y.S.D. would like to acknowledge the support from NSFC grants 12273051 and 10878003. M.R. is supported by the international Gemini Observatory, a program of NSFs NOIRLab, which is managed by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with the National Science Foundation, on behalf of the Gemini partnership of Argentina, Brazil, Canada, Chile, the Republic of Korea, and the United States of America. The JCMT is operated by the East Asian Observatory on behalf of The National Astronomical Observatory of Japan; Academia Sinica Institute of Astronomy and Astrophysics; the Korea Astronomy and Space Science Institute; the Operation, Maintenance and Upgrading Fund for Astronomical Telescopes and Facility Instruments, budgeted from the Ministry of Finance of China. Additional funding support is provided by the Science and Technology Facilities Council of the United Kingdom and participating universities and organizations in the United Kingdom, Canada, and Ireland. Additional funds for the construction of SCUBA-2 were provided by the Canada Foundation for Innovation.

Magnetic fields play an important role in the evolution of molecular clouds and star formation. Using the Velocity Gradient Technique (VGT) model, we measured the magnetic field in Orion A using the 12CO, 13CO, and C18O (1-0) emission lines at a scale of 0.07 pc. The measured B-field shows an east-west orientation that is perpendicular to the integral shaped filament of Orion A at large scale. The VGT magnetic fields obtained from 13CO and C18O are in agreement with the B-field that is measured from the Planck 353 GHz dust polarization at a scale of 0.55 pc. Removal of density effects by using a Velocity Decomposition Algorithm can significantly improve the accuracy of the VGT in tracing magnetic fields with the 12CO (1-0) line. The magnetic field strength of seven sub-clouds, OMC-1, OMC-2, OMC-3, OMC-4, OMC-5, L 1641-N, and NGC 1999 has also been estimated with the Davis-Chandrasekhar-Fermi (DCF) and MM2 technique, and these are found to be in agreement with previous results obtained from dust polarization at far-infrared and sub-millimeter wavelengths. At smaller scales, the VGT proves a good method to measure magnetic fields., Comment: 15 pages, 6 figures, accepted to ApJ

Here we present the study on chemical properties of massive star forming clumps using N $ _2 $ H $ ^+ $ (1-0), H $ ^{13} $ CO $ ^+ $ (1-0), HCN(1-0) and HN $ ^{13} $ C(1-0) data from the literature [Astron. Astrophys. 563, A97 (2014)]. We found that abundances of H $ ^{13} $ CO $ ^+ $ and HN $ ^{13} $ C are affected by H $ _2 $ column densities. As the median values of these two abundances increase by nearly 10 times from stages A to B, H $ ^{13} $ CO $ ^+ $ and HN $ ^{13} $ C are suitable for tracing the evolution of massive star forming clumps. The order of rapidity in growth of abundances of all the four studied molecules from stages A to B, is H $ ^{13} $ CO $ ^+ $ , HCN, HN $ ^{13} $ C, and N $ _2 $ H $ ^+ $ , from the highest to the lowest. Our results suggest that the observing optically thin molecular lines with high angular resolution are necessary to study the chemical evolution of massive star forming clumps.

In this study, waterjet peening (WJP) treatments under different water pressures were utilized to improve the mechanical properties of 304 stainless steel. The surface morphologies, microstructures, phases, and mechanical properties under different pressures in the WJP process were systematically investigated. The results show that WJP treatments successfully introduced a hardening layer and residual compressive stress. The optimal hardening layer, hardness, residual compressive stress, tensile strength, and ductility were all recorded at the pressure of 200 MPa. The improved hardness, tensile strength, and ductility of 304 stainless steel treated with WJP treatments at the pressure of 200 MPa can be attributed to the hardening layer with much apparent grain refinement effect, phase transformation, smaller surface roughness, and a specific residual compressive stress, as compared with the WJP treatments under other water pressures.

We present the results of simultaneous 450 $\mu$m and 850 $\mu$m polarization observations toward the massive star forming region NGC 2071IR, a target of the BISTRO (B-fields in Star-Forming Region Observations) Survey, using the POL-2 polarimeter and SCUBA-2 camera mounted on the James Clerk Maxwell Telescope. We find a pinched magnetic field morphology in the central dense core region, which could be due to a rotating toroidal disk-like structure and a bipolar outflow originating from the central young stellar object, IRS 3. Using the modified Davis-Chandrasekhar-Fermi method, we obtain a plane-of-sky magnetic field strength of 563$\pm$421 $\mu$G in the central $\sim$0.12 pc region from 850 $\mu$m polarization data. The corresponding magnetic energy density of 2.04$\times$10$^{-8}$ erg cm$^{-3}$ is comparable to the turbulent and gravitational energy densities in the region. We find that the magnetic field direction is very well aligned with the whole of the IRS 3 bipolar outflow structure. We find that the median value of polarization fractions, 3.0 \%, at 450 $\mu$m in the central 3 arcminute region, which is larger than the median value of 1.2 \% at 850 $\mu$m. The trend could be due to the better alignment of warmer dust in the strong radiation environment. We also find that polarization fractions decrease with intensity at both wavelengths, with slopes, determined by fitting a Rician noise model, of $0.59 \pm 0.03$ at 450 $\mu$m and $0.36 \pm 0.04$ at 850 $\mu$m, respectively. We think that the shallow slope at 850 $\mu$m is due to grain alignment at the center being assisted by strong radiation from the central young stellar objects., Comment: 17 pages, 11 figures, 4 tables

We have obtained sensitive dust continuum polarization observations at 850 μm in the B213 region of Taurus using POL-2 on SCUBA-2 at the James Clerk Maxwell Telescope as part of the B-fields in STar-forming Region Observations (BISTRO) survey. These observations allow us to probe magnetic field (B-field) at high spatial resolution (∼2000 au or ∼0.01 pc at 140 pc) in two protostellar cores (K04166 and K04169) and one prestellar core (Miz-8b) that lie within the B213 filament. Using the Davis–Chandrasekhar–Fermi method, we estimate the B-field strengths in K04166, K04169, and Miz-8b to be 38 ± 14, 44 ± 16, and 12 ± 5 μG, respectively. These cores show distinct mean B-field orientations. The B-field in K04166 is well ordered and aligned parallel to the orientations of the core minor axis, outflows, core rotation axis, and large-scale uniform B-field, in accordance with magnetically regulated star formation via ambipolar diffusion taking place in K04166. The B-field in K04169 is found to be ordered but oriented nearly perpendicular to the core minor axis and large-scale B-field and not well correlated with other axes. In contrast, Miz-8b exhibits a disordered B-field that shows no preferred alignment with the core minor axis or large-scale field. We found that only one core, K04166, retains a memory of the large-scale uniform B-field. The other two cores, K04169 and Miz-8b, are decoupled from the large-scale field. Such a complex B-field configuration could be caused by gas inflow onto the filament, even in the presence of a substantial magnetic flux.

We report the first high spatial resolution measurement of magnetic fields surrounding LkH$\alpha$ 101, a part of the Auriga-California molecular cloud. The observations were taken with the POL-2 polarimeter on the James Clerk Maxwell Telescope within the framework of the B-fields In Star-forming Region Observations (BISTRO) survey. Observed polarization of thermal dust emission at 850 $\mu$m is found to be mostly associated with the red-shifted gas component of the cloud. The magnetic field displays a relatively complex morphology. Two variants of the Davis-Chandrasekhar-Fermi method, unsharp masking and structure function, are used to calculate the strength of magnetic fields in the plane of the sky, yielding a similar result of $B_{\rm POS}\sim 115$ $\mathrm{\mu}$G. The mass-to-magnetic-flux ratio in critical value units, $\lambda\sim0.3$, is the smallest among the values obtained for other regions surveyed by POL-2. This implies that the LkH$\alpha$ 101 region is sub-critical and the magnetic field is strong enough to prevent gravitational collapse. The inferred $\delta B/B_0\sim 0.3$ implies that the large scale component of the magnetic field dominates the turbulent one. The variation of the polarization fraction with total emission intensity can be fitted by a power-law with an index of $\alpha=0.82\pm0.03$, which lies in the range previously reported for molecular clouds. We find that the polarization fraction decreases rapidly with proximity to the only early B star (LkH$\alpha$ 101) in the region. The magnetic field tangling and the joint effect of grain alignment and rotational disruption by radiative torques are potential of explaining such a decreasing trend., Comment: 25 pages, 19 figures, Accepted for publication in The Astrophysical Journal

We mapped the kinetic temperature structure of Orion KL in a $\sim$20$''$ ($\sim$8000 AU) sized region with para-H$_{2}$CS $7_{07}-6_{06}$, $7_{26}-6_{25}$, and $7_{25}-6_{24}$ making use of ALMA Band 6 Science Verification data. The kinetic temperatures obtained with a resolution of $1\hbox{$\,.\!\!^{\prime\prime}$}65$$\times$$1\hbox{$\,.\!\!^{\prime\prime}$}14$ ($\sim$550 AU) are deduced by modeling the measured averaged velocity-integrated intensity ratios of para-H$_2$CS $7_{26}-6_{25}/7_{07}-6_{06}$ and $7_{25}-6_{24}/7_{07}-6_{06}$ with a RADEX non-LTE model. The kinetic temperatures of the dense gas, derived from the para-H$_2$CS line ratios at a spatial density of 10$^7$ cm$^{-3}$, are high, ranging from 43 to $>$500 K with an unweighted average of $\sim$170 K. There is no evidence for internal sources playing an important role in the heating of the various structures identified in previous work, namely the elongated ridge, the northwestern clump, and the eastern region of the compact ridge, while the high temperatures in the western region of the compact ridge may be dominated by internal massive star formation. Significant gradients of kinetic temperature along molecular filaments traced by H$_2$CS indicate that the dense gas is heated by the shocks induced by the enigmatic explosive event, which occurred several hundred years ago greatly affecting the energetics of the Orion KL region. Thus, with the notable exception of the western region of the compact ridge, the high temperatures of the dense gas in Orion KL are probably caused by shocks from the explosive event, leading to a dominant component of externally heated dense gas., Accepted for publication to ApJ

We present new observations of the active star formation region NGC 1333 in the Perseus molecular cloud complex from the James Clerk Maxwell Telescope B -Fields In Star-forming Region Observations (BISTRO) survey with the POL-2 instrument. The BISTRO data cover the entire NGC 1333 complex (∼1.5 pc × 2 pc) at 0.02 pc resolution and spatially resolve the polarized emission from individual filamentary structures for the first time. The inferred magnetic field structure is complex as a whole, with each individual filament aligned at different position angles relative to the local field orientation. We combine the BISTRO data with low- and high- resolution data derived from Planck and interferometers to study the multiscale magnetic field structure in this region. The magnetic field morphology drastically changes below a scale of ∼1 pc and remains continuous from the scales of filaments (∼0.1 pc) to that of protostellar envelopes (∼0.005 pc or ∼1000 au). Finally, we construct simple models in which we assume that the magnetic field is always perpendicular to the long axis of the filaments. We demonstrate that the observed variation of the relative orientation between the filament axes and the magnetic field angles are well reproduced by this model, taking into account the projection effects of the magnetic field and filaments relative to the plane of the sky. These projection effects may explain the apparent complexity of the magnetic field structure observed at the resolution of BISTRO data toward the filament network., Erratum published in volume 899, issue 1, 5 p., April 10 2021. DOI: 10.3847/1538-4357/abf2b3