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AIM: To evaluate the efficacy of intravitreal injection of anti-vascular endothelial growth factor (anti-VEGF), photodynamic therapy (PDT), and laser treatment (LT) for anatomical and functional improvement in myopic choroidal neovascularization (mCNV) patients. METHODS: Two researchers independently searched PubMed, Cochrane Library, Web of Science, and other databases to screen studies comparing best-corrected vision acuity (BCVA) and foveal center thickness (FCT) changes after mCNV treatment. Post-treatment chorioretinal atrophy (CRA) is a secondary outcome indicator. The retrieval time limit is from the database construction to January 30, 2023. RESULTS: A total of 1072 eyes in 16 articles were included. In the RCTs, intravitreal bevacizumab (IVB) and intravitreal ranibizumab (IVR) were superior to PDT (MD=0.18, 95%CI: 0.02, 0.40, MD=0.18, 95%CI: 0.01, 0.42) in improving BCVA of mCNV patients (P

Myopia is a harmful ophthalmic disease that may change the activity of the visual cortex and affect the corresponding neural function. At present, the incidence rate of myopia in China has been rising unprecedentedly, especially in high myopia(HM). Therefore, efficacious prevention and treatment of myopia are extremely important. However, since the specific pathogenesis of myopia has not been clarified so far, it is difficult to achieve the prevention and control of the disease at its source. Recently, there have been studies on the pathogenesis of myopia from the perspective of genetics, environment, neurotransmitters, etc., but few studies have explored the neuroimaging mechanism of myopia from the perspective of brain structure and function. With the development of magnetic resonance imaging(MRI)technology, brain images gradually appear in the study of myopia-related mechanisms. Therefore, this paper summarizes the research on myopia-related brain images, to provide an important reference for the clinical prevention and control of myopia.

We report detection results of nine millisecond pulsars (MSPs) at 8600 MHz using simultaneous 2250 and 8600 MHz observations conducted with the Shanghai Tian Ma Radio Telescope. Mainly benefiting from updated ephemerids with 2250 MHz observations, integrated profiles of all nine MSPs at 8600 MHz are successfully obtained by coherently adding multi-epoch (3–83 epochs) observation data spanning from 19–1210 days, which significantly increases the number of MSPs with published profiles (from 4 to 11) above 8000 MHz, as seven of our target MPSs had no related results previously. Combining our new flux density and pulse width measurements with previous low-frequency results, we study their integrated profile evolution and spectral behaviors in a wider frequency range. We find their component separations and pulse widths remain almost constant, which is consistent with previous findings. While dramatic evolution of integrated profiles exists at low frequencies, we observe a potential end of the related evolution around 5 GHz in eight MSPs. The spectra of four MSPs are found to deviate from a single power law, and we fit them with a broken power law. The change in the profile of PSR J1713+0747, which started around MJD 59320−59321, seems to be more prominent as the observation frequency increases. Compared with the effects of the interstellar medium, we prefer to explain this event as some changes in the magnetosphere. We also find its integrated profile possibly had not recovered to the pre-event state until MJD 59842–59857.

The ionosphere is an important component of near-Earth space that has a significant impact on communication and navigation. Furthermore, the total electron content (TEC) of the ionosphere is a widely used parameter in near-Earth plasma environment studies. A design of a digital beacon receiver system for automatically measuring TEC is presented. Universal Software Radio Peripheral (USRP) hardware equipment with software-defined radio technology was used in the tri-band beacon digital receiver to receive and rapidly preprocess beacon signals from satellites in different frequency bands. A software system is built to implement the automatic control of the receiver and to enable data processing of the preprocessed data in order to obtain its phase information and derive the TEC. The tri-band digital beacon receiver system is experimentally proven to automatically detect and archive transit satellites in real time, automatically receive and process satellite beacon signals with recording, and automatically generate TEC measurement results.

Abstract Background Microcirculatory disturbance is closely associated with multiple diseases such as ischemic and septic stroke. Luteolin (3,4,5,7-tetrahydroxyflavone) is a vascular protective flavonoid present in several dietary foods. However, how luteolin plays a role in microcirculatory disturbance is still unknown. The purpose of this study was to find out the influence of luteolin on the lipopolysaccharide (LPS)-induced microcirculatory disturbance, focusing on its effect on leukocyte adhesion and the underlying mechanism of this effect. Methods After injecting LPS into rats, we used an inverted intravital microscope to observe the velocity of red blood cells in venules, numbers of leukocytes adherent to and emigrated across the venular wall, hydrogen peroxide production in venular walls and mast cell degranulation. Intestinal microcirculation blood flow was measured by High-resolution Laser Doppler Perfusion Imaging. Histological changes of small intestine and mesenteric arteries were evaluated. Additionally, cell adhesion stimulated by LPS was tested on EA.hy926 and THP-1 cells. The production of pro-inflammatory cytokines, adhesion molecules and the activation of TLR4/Myd88/NF-κB signaling pathway were determined. Results The results showed luteolin significantly inhibited LPS-induced leukocyte adhesion, hydrogen peroxide production and mast cell degranulation, and increased intestinal microcirculation blood flow and ameliorated pathological changes in the mesenteric artery and the small intestine. Furthermore, luteolin inhibited the release of pro-inflammatory cytokines, the expression of TLR4, Myd88, ICAM-1, and VCAM-1, the phosphorylation of IκB-α and NF-κB/p65 in LPS stimulated EA.hy926. Conclusions Our findings revealed that it is likely that luteolin can ameliorate microcirculatory disturbance. The inhibitory effects of luteolin on the leukocyte adhesion stimulated by LPS, which participates in the development of microcirculatory disturbance, are mediated through the regulation of the TLR4/Myd88/NF-κB signaling pathway.

We did 194 epochs of simultaneous 2.25/8.60 GHz observations of XTE J1810−197 in 926 days shortly following its reactivation in 2018 with Shanghai Tian Ma Radio Telescope (TMRT). Although its integrated profiles changed with both time and frequency during this period, they could be classified into 12 types according to phase areas of active radiation components. After MJD 59015, XTE J1810−197 turned from the normal emission state into the spiky emission state that was manifesting as a series of bright narrow sub-pulse bursts at both 2.25 and 8.60 GHz. Due to its variable integrated profiles and unsteady rotations, we got the spin frequency ν and spin-frequency derivatives $\dot{\nu }$ with the piecewise fitting method. In addition, its long-term declining trend of ν was also obtained as $\dot{\nu }=-3.2(1)\times {10}^{-13}$ s ^−2 with the linear fitting method based on our observations spanning a comparatively longer period. We found its flux densities went through three stages: sharp decrease, stabilization, and day-to-day fluctuations in our dual-frequency observations. Although the flux density showed different stages, XTE J1810−197 showed a relatively flat spectrum ( α > –1) in most observations. Assuming an ideal dipole magnetic field as some previous research works, we obtained the emission heights of XTE J1810−197 were about 7.5(9) × 10 ^4 km and 2.38(7) × 10 ^4 km at 2.25 and 8.60 GHz, respectively. We also found that its emission heights would decrease rapidly with the degree of magnetic field twisting.

We have conducted a systematic line survey, primarily focused on transitions of the methanol and ammonia molecules, and monitoring observations of masers toward the high-mass star-forming region NGC 6334I. These observations were undertaken between 2019 and 2022 in the C, K, Ka , and Q bands with the Tianma Radio Telescope. In total, 63 CH _3 OH (including 11 class I and nine class II maser or maser candidate), 18 ^13 CH _3 OH, and 34 NH _3 (including seven maser or maser candidate) transitions were detected. The emission is likely associated with the luminosity outburst source MM1. Rotation diagram analysis of multiple ammonia transitions shows that the gas temperature in the molecular core was a factor of 2 higher than that measured in previous observations in the pre-burst stage. This suggests that the molecular core has likely been heated by radiation originating from the luminosity outburst. Maser variability in the methanol and excited-state OH masers shows a general trend that the maser components associated with the luminosity outburst have decreased in their intensity since 2020. The decay in the maser luminosity indicates that the outburst is possibly declining, and as a result, the duration of the MM1 luminosity outburst may be shorter than the predicted 40 yr duration. Compared to the masers detected toward another luminosity outburst source, G358.93-0.03, abundant class I methanol masers and strong water maser flares were also detected toward NGC 633I, but masers from rare class II methanol transitions and new molecules were absent toward NGC 6334I. The large number of detections of maser transitions toward the two burst sources provided a database for further maser modeling to explore the physical environments associated with accretion burst events.

AIM: To compare the anatomic and functional outcomes between vitrectomy with internal limiting membrane (ILM) peeling and internal ILM flap insertion technique for high myopia macular hole (MH). METHODS: PubMed, Cochrane Library, EMBASE, and CNKI were systematically searched, and all studies involved MH were included. The closure rate of MH and the postoperative best-corrected visual acuity (BCVA) at 6mo after the initial surgery were the primary measures. All statistical tests were performed in Review Manager 5.3. RESULTS: Five studies that included 151 eyes of 151 patients were finally included, all of which were retrospectively comparative studies. Between the pars plana vitrectomy (PPV) with ILM peeling surgery and the ILM insertion technique, the latter had significantly better efficacy with respect to the closure rate of MH (OR=21.32, 95%CI=7.25-62.67, P

Thyroid-associated ophthalmopathy(TAO)is the most common orbital disease in adults. Its ocular damage is becoming more and more serious, which causes great harm to the physical and mental health of patients. The pathogenesis of TAO is very complex and has not yet been fully elucidated. The classical theory is the theory of co-antigens. In view of the drawbacks of existing treatment schemes, it is of great significance to study the factors related to TAO and explore better treatment methods for TAO patients. In recent years, the relationship between inflammatory response and TAO has been found, therefore this article reviews the research on TAO-related inflammatory factors.

Pollen contains various antioxidants, including flavonoids, which are beneficial to cardiovascular health. However, the protective effect and mechanism of pollen flavonoids extract on the cardiovascular system are still unclear. Herein, the protective effects of crude flavonoids of pollen (CFP) from canola (Brassica campestris L.) on tert-butyl hydroperoxide (TBHP)-induced cell injury were assessed in the EA.hy926 cell line. Then, the potential mechanism by which canola CFP protects vascular endothelial cells was explored at the proteome level and was verified by determining relevant indicators. Canola CFP exerted antioxidant and anti-inflammatory effects on the EA.hy926 cell injury model. Proteomics analysis and mechanism verification assays demonstrated that pretreatment with canola CFP produced effects primarily through maintenance of normal redox, mitochondrial function and lipid metabolism in cells. Our results indicate that canola CFP has great potential for preventing TBHP-induced vascular endothelial cell dysfunction.

Genetic alterations which impair the function of the TP53 signaling pathway in TP53 wild-type human tumors remain elusive. To identify new components of this pathway, we performed a screen for genes whose loss-of-function debilitated TP53 signaling and enabled oncogenic transformation of human mammary epithelial cells. We identified transglutaminase 2 (TGM2) as a putative tumor suppressor in the TP53 pathway. TGM2 suppressed colony formation in soft agar and tumor formation in a xenograft mouse model. The depletion of growth supplements induced both TGM2 expression and autophagy in a TP53-dependent manner, and TGM2 promoted autophagic flux by enhancing autophagic protein degradation and autolysosome clearance. Reduced expression of both CDKN1A, which regulates the cell cycle downstream of TP53, and TGM2 synergized to promote oncogenic transformation. Our findings suggest that TGM2-mediated autophagy and CDKN1A-mediated cell cycle arrest are two important barriers in the TP53 pathway that prevent oncogenic transformation.

Atherosclerotic stenosis of cerebral arteries or intracranial large artery disease (ICLAD) is a major cause of stroke especially in Asians, Hispanics and Africans, but relatively little is known about gene expression changes in vessels at risk. This study compares comprehensive gene expression profiles in the middle cerebral artery (MCA) of New Zealand White rabbits exposed to two stroke risk factors i.e. hypertension and/or hypercholesterolemia, by the 2-Kidney-1-Clip method, or dietary supplementation with cholesterol. Microarray and Ingenuity Pathway Analyses of the MCA of the hypertensive rabbits showed up-regulated genes in networks containing the node molecules: UBC (ubiquitin), P38 MAPK, ERK, NFkB, SERPINB2, MMP1 and APP (amyloid precursor protein); and down-regulated genes related to MAPK, ERK 1/2, Akt, 26 s proteasome, histone H3 and UBC. The MCA of hypercholesterolemic rabbits showed differentially expressed genes that are surprisingly, linked to almost the same node molecules as the hypertensive rabbits, despite a relatively low percentage of 'common genes' (21 and 7%) between the two conditions. Up-regulated common genes were related to: UBC, SERPINB2, TNF, HNF4A (hepatocyte nuclear factor 4A) and APP, and down-regulated genes, related to UBC. Increased HNF4A message and protein were verified in the aorta. Together, these findings reveal similar nodal molecules and gene pathways in cerebral vessels affected by hypertension or hypercholesterolemia, which could be a basis for synergistic action of risk factors in the pathogenesis of ICLAD.

In radio astronomy observations, radio frequency interference (RFI) is mixed into the telescope receiving system in various forms. The existence of RFI brings misjudgment to the observation or reduces the observational signal-to-noise ratio. In recent years, the domestic and overseas radio astronomy has developed rapidly. Large-scale radio telescopes and telescope arrays at home and abroad have been constructed successively. Observation sensitivity is greatly improved, and the influence of RFI is particularly prominent. With the development of science and technology and the intensification of human activities, the RFI has become increasingly serious and irreversible. We propose to use the two-dimensional discrete wavelet transform method to analyze the data of radio astronomy observations, and to perform wavelet transform on the time-frequency sequence output by the telescope system. According to the wavelet coefficients, the every component in the original signal is separated, and the corresponding threshold value is obtained by the statistics on each component. Each component is compared with the threshold to identify the interference component, and to mark it for removal. This method is used to process the actual observation data. The results show that this method can well mark and eliminate the interference signal, and improve the observational signal-to-noise ratio. [ABSTRACT FROM AUTHOR]

Emission geometries, including emission region heights, beam shapes and radius-to-frequency mapping, are important clues for pulsar radiation models. Multiband radio observations reveal this valuable information. In this paper, we study two bright pulsars, PSRs B0329+54 and B1642-03, and observe them at high frequencies: 2.5, 5 and 8 GHz. The newly acquired data, together with historical archives, provide an atlas of multifrequency profiles spanning from 100 MHz to 10 GHz. We study the frequency evolution of pulse profiles as well as radiation regions using these data. First, we fit the pulse profiles with Gaussian functions to determine the phase of each component, and then we calculate the radiation altitudes of different emission components and radiation regions. We find that the inverse Compton scattering (ICS) model can reproduce the radiation geometry of these two pulsars. However, for PSR B0329+54, the radiation can be generated in either an annular gap (AG) or a core gap (CG), while the radiation of PSR B1642-03 can only be generated in a CG. This difference is caused by the inclination angle and the impact angle of these two pulsars. The relationship between the beaming angle (the angle between the radiation direction and the magnetic axis) and the radiation altitude versus frequency is also presented by modelling the beam–frequency evolution in the ICS model. The multiband pulse profiles of these two pulsars can be described well by the ICS model combined with the CG and AG. [ABSTRACT FROM AUTHOR]

We report the results of the OH maser observation towards the water fountain source IRAS 18286–0959 using the newly built Shanghai Tianma 65-m Radio Telescope. We observed the three OH ground state transition lines at frequencies of 1612, 1665 and 1667 MHz. Comparing with the spectra of previous observations, we find new maser spectral components at velocity channels largely shifted from the systemic velocity: the velocity offsets of the newly found components lie in the range 20-40 km s-1 with respect to the systemic velocity. Besides maser variability, another possible interpretation for the newly detected maser features is that part of the molecular gas in the circumstellar envelope is accelerated. The acceleration is probably caused by the passage of a high-velocity molecular jet, which has been detected in previous Very Long Baseline Interferometry observations in the H2O maser line. [ABSTRACT FROM AUTHOR]

In order to carry out the spectral observation with the TM65m radio telescope, the frequency calibration and test of DIBAS (Digital Backend System) are performed, it is found that it has a good performance. First, by injecting the PCAL signals, the frequency resolution, frequency drift and the stability of frequency interval between two spectral lines of the DIBAS backend are measured. It is found that in one hour, the maximum frequency drift of a single spike is 0.03 channel, the maximum fluctuation of spike interval is 0.05 channel. Then, by the observations on the H 2 CO maser and absorbtion lines of massive star formation regions, and the comparison with the results observed by the GBT (Robert C. Byrd Green Bank Telescope), it is shown that the results of frequency calibration are correct. Finally, by the OH maser observations in more than one hour toward W3(OH), and the methanol maser observations in more than 5 hours, it is found that the spectral profiles keep consistent, and the observational noise is consistent with the theoretical value, indicating the stability and reliability of the frequency calibration program. [ABSTRACT FROM AUTHOR]

The lipotoxicity hypothesis posits that obesity predisposes individuals to metabolic diseases because the oversupply of lipids to tissues not suited for fat storage leads to the accumulation of fat-derived molecules that impair tissue function. Means of combating this have been to stimulate anabolic processes to promote lipid storage or to promote catabolic ones to drive fat degradation. Herein, we demonstrate that ablating dihydroceramide desaturase 1 (Des1), an enzyme that produces ceramides, leads to the simultaneous activation of both anabolic and catabolic signaling pathways. In cells lacking DesI, the most common sphingolipids were replaced with dihydro forms lacking the double bond inserted by Des1. These cells exhibited a remarkably strong activation of the antiapoptotic and anabolic signaling pathway regulated by Akt/protein kinase B (PKB), were resistant to apoptosis, and were considerably larger than their wild-type counterparts. Paradoxically, Des1-/- cells exhibited high levels of autophagy. Mechanistic studies revealed that this resulted from impaired ATP synthesis due in part to decreased expression and activity of several complexes of the electron transport chain, particularly complex IV, leading to activation of AMP-activated protein kinase and its induction of the autophagosome. Thus, Des1 ablation enhanced starvation responses but dissociated them from the anabolic, prosurvival, and antiautophagic Akt/PKB pathways. [ABSTRACT FROM AUTHOR]

Recently, we have demonstrated that F3/contactin and NB-3 are trans-acting extracellular ligands of Notch that promote differentiation of neural stem cells and oligodendrocyte precursor cells into mature oligodendrocytes (OLs). Here, we demonstrate that human bone marrow stromal cells (hBMSCs) can be induced to differentiate into cells with myelinating glial cell characteristics in mouse retina after predifferentiation in vitro. Isolated CD90(+) hBMSCs treated with β-mercaptoethanol for 1 day and retinoic acid for 3 days in culture changed into myelinating glia-like cells (MGLCs). More cells expressed NG2, an early OL marker, after treatment, but expression of O4, a mature OL marker, was negligible. Subsequently, the population of O4(+) cells was significantly increased after the MGLCs were predifferentiated in culture in the presence of either F3/contactin or multiple factors, including forskolin, basic fibroblast growth factor, platelet-derived growth, factor, and heregulin, in vitro for another 3 days. Notably, 2 months after transplantation into mouse retina, the predifferentiated cells changed morphologically into cells resembling mature MGLCs and expressing O4 and myelin basic protein, two mature myelinating glial cell markers. The cells sent out processes to contact and wrap axons, an event that normally occurs during early stages of myelination, in the retina. The results suggest that CD90(+) hBMSCs are capable of morphological and functional differentiation into MGLCs in vivo through predifferentiation by triggering F3/Notch signaling in vitro. [ABSTRACT FROM AUTHOR]

Describes the development of a polymerase chain reaction method based on amplification of a specific DNA fragment for the identification of camel, Camelus materials. Design of a species-specific primer pair L183/H372 based no the nucleotide sequence of the mitochondrial cytochrome b gene; Amplification of a pair fragment.

We have investigated the mode changing properties of PSR B0329+54 using 31 epochs of simultaneous 13 cm/3 cm single-pulse observations obtained with the Shanghai Tian Ma 65 m telescope. The pulsar was found in the abnormal emission mode 17 times, accounting for ∼13% of the 41.6 hr total observation time. Single-pulse analyses indicate that mode changes took place simultaneously at 13 cm/3 cm within a few rotational periods. We detected occasional bright and narrow pulses whose peak flux densities were 10 times higher than that of the integrated profile in both bands. At 3 cm, about 0.66% and 0.27% of single pulses were bright in the normal mode and abnormal mode, respectively, but at 13 cm the occurrence rate was only about 0.007%. We divided the pulsar radiation window into three components (C1, C2, and C3) corresponding to the main peaks of the integrated profile. The bright pulses preferentially occurred at pulse phases corresponding to the peaks of C2 and C3. Fluctuation spectra showed that C2 had excess red noise in the normal mode, but broad quasi-periodic features with central frequencies around 0.12 cycles/period in the abnormal mode. At 3 cm, C3 had a stronger quasi-periodic modulation centered around 0.06 cycles/period in the abnormal mode. Although there were some asymmetries in the two-dimensional fluctuation spectra, we found no clear evidence for systematic subpulse drifting. Consistent with previous low-frequency observations, we found a very low nulling probability for B0329+54, with upper limits of 0.13% and 1.68% at 13 cm/3 cm, respectively. [ABSTRACT FROM AUTHOR]

We performed a systematic 6.7 GHz Class II methanol maser survey using the Shanghai Tianma Radio Telescope toward targets selected from the all-sky Wide-Field Infrared Survey Explorer (WISE) point catalog. In this paper, we report the results from the survey of those at high Galactic latitudes, i.e., 2°. Of 1473 selected WISE point sources at high latitude, 17 point positions that were actually associated with 12 sources were detected with maser emission, reflecting the rarity (1%–2%) of methanol masers in the region away from the Galactic plane. Out of the 12 sources, 3 are detected for the first time. The spectral energy distribution at infrared bands shows that these new detected masers occur in the massive star-forming regions. Compared to previous detections, the methanol maser changes significantly in both spectral profiles and flux densities. The infrared WISE images show that almost all of these masers are located in the positions of the bright WISE point sources. Compared to the methanol masers at the Galactic plane, these high-latitude methanol masers provide good tracers for investigating the physics and kinematics around massive young stellar objects, because they are believed to be less affected by the surrounding cluster environment. [ABSTRACT FROM AUTHOR]

Integrated pulse profiles at 8.6 GHz obtained with the Shanghai Tian Ma Radio Telescope (TMRT) are presented for a sample of 26 pulsars. Mean flux densities and pulse width parameters of these pulsars are estimated. For 11 pulsars these are the first high-frequency observations and for a further four, our observations have a better signal-to-noise ratio than previous observations. For one (PSR J0742−2822), the 8.6 GHz profile differs from previously observed profiles. A comparison of 19 profiles with those at other frequencies shows that in nine cases, the separation between the outmost leading and trailing components decreases with frequency, which is roughly in agreement with radius-to-frequency mapping, whereas in the other 10 the separation is nearly constant. Different spectral indices of profile components lead to the variation of integrated pulse profile shapes with frequency. In seven pulsars with multi-component profiles, the spectral indices of the central components are steeper than those of the outer components. For the 12 pulsars with multi-component profiles in the high-frequency sample, we estimate the core width using Gaussian fitting and discuss the width-period relationship. [ABSTRACT FROM AUTHOR]

The lunar rendezvous and docking (RVD) technology is an important guarantee for our third phase of lunar exploration. In this paper, by using VLBI (Very Long Baseline Interferometry) delay of CE03 (Chang'e-03) which was around the lunar, the changing of differential group delay (DGD) under the SBI (same-beam VLBI) observation mode was simulated. The simulation results indicated that the orbit distance between Orbiter and Ascender Combination (Ascender and Returner) was kept in 100 kilometers, and it lasted for half an hour, the track information of these two were well reflected by DGD which can be used for orbit determination. In the approach stage, DGD is rapidly approaching to 0, as Ascender Combination accelerated and closed to the orbiter, while the orbit distance was reduced from 5 km to 20 m, and was rapidly increased as Ascender Combination was far away from Orbiter. At last, using VLBI delay of CE03 which was halfway to the lunar, and transmitted two DOR (Differential One-Ranging) signals that were observed by CVN (Chinese VLBI Network), we calculated DPD (Differential Phase Delay), and preliminarily showed the error of DPD. [ABSTRACT FROM AUTHOR]

We report Shanghai Tian Ma Radio Telescope (TMRT) detections of several long carbon-chain molecules in the C and Ku bands, including HC3N, HC5N, HC7N, HC9N, C3S, C6H, and C8H toward the starless cloud Serpens South 1a. We detected some transitions (HC9N J = 13–12, F = 12–11, and F = 14–13; H13CCCN J = 2–1, F = 1–0, and F = 1–1; HC13CCN J = 2–1, F = 2–2, F = 1–0, and F = 1–1; HCC13CN J = 2–1, F = 1–0, and F = 1–1) and resolved some hyperfine components (HC5N J = 6–5, F = 5–4; H13CCCN J = 2–1, F = 2–1) for the first time in the interstellar medium. The column densities of these carbon-chain molecules in the range 1012–1013 cm−2 are comparable to two carbon-chain molecule rich sources, TMC-1 and Lupus-1A. The abundance ratios are 1.00:(1.11 ± 0.15):(1.47 ± 0.18) for [H13CCCN]:[HC13CCN]:[HCC13CN]. This result implies that the 13C isotope is also concentrated in the carbon atom adjacent to the nitrogen atom in HC3N in Serpens South 1a, which is similar to TMC-1. The [HC3N]/[H13CCCN] ratio of 78 ± 9, the [HC3N]/[HC13CCN] ratio of 70 ± 8, and the [HC3N]/[HCC13CN] ratio of 53 ± 4 are also comparable to those in TMC-1. Serpens South 1a proves to be a suitable testing ground for understanding carbon-chain chemistry. [ABSTRACT FROM AUTHOR]

In this paper, we report radio observations of the Galactic Center magnetar PSR J1745–2900 at six epochs between 2014 June and October. These observations were carried out using the new Shanghai Tian Ma Radio Telescope at a frequency of 8.6 GHz. Both the flux density and integrated profile of PSR J1745–2900 show dramatic changes from epoch to epoch, showing that the pulsar was in its “erratic” phase. On MJD 56836, the flux density of this magnetar was about 8.7 mJy, which was 10 times larger than that reported at the time of discovery, enabling a single-pulse analysis. The emission is dominated by narrow “spiky” pulses that follow a log-normal distribution in peak flux density. From 1913 pulses, we detected 53 pulses whose peak flux densities are 10 times greater than that of the integrated profile. They are concentrated in pulse phase at the peaks of the integrated profile. The pulse widths at the 50% level of these bright pulses were between 0.°2 and 0.°9, much narrower than that of the integrated profile (∼12°). The observed pulse widths may be limited by interstellar scattering. No clear correlation was found between the widths and peak flux density of these pulses and no evidence was found for subpulse drifting. Relatively strong spiky pulses are also detected in the other five epochs of observation, showing the same properties as those detected in MJD 56836. These strong spiky pulses cannot be classified as “giant” pulses but are more closely related to normal pulse emission. [ABSTRACT FROM AUTHOR]

On 14th December 2013, the Chang’E-3 made a successful soft landing on the lunar surface, and then carried out the tasks of separating the lander and the rover, and taking pictures of each other. With the same beam VLBI (Very Long Baseline Interferometry) technique to observe the signals transmitted by the lander and the rover simultaneously, the differential phase delay between them is calculated, which can reflect the minor changes of the rover's position on a scale of a few centimeters. Based on the high sensitivity of differential phase delay, the rover's speeds during 5 movements are obtained with an average of 0.056 m/s. The relationship between the rover's shake in the moving process and the lunar terrain is analyzed by using the spectrum of the residual of the differential phase delay after the first-order polynomial fitting. [ABSTRACT FROM AUTHOR]