STUDY ON PHASE-SEPARATION OF PMMA/SAN BLENDS INDUCED BY GLASS BEADS THROUGH DYNAMIC RHEOLOGICAL MEASUREMENTS

Based on the premise that the addition of glass beads （GB） could hardly influence the linear viscoelasticity in low frequency （ω） region for homogeneous polymer systems, the dynamic rheological behaviors of unfilled and filled poly（methyl methyacrylate） （PMMA）/poly（styrene-co-acrylonitrile） （SAN） blends were studied in order to explore the effect of GB on the phase-separation of binary polymer matrix. Results show that GB has an induced effect on the phase-separation, which embodies that the phase-separation temperature （Ts） of PMMA/SAN blend filled with GB is lower than that of the unfilled system. The higher content of GB, the higher is the ＂secondary plateau＂ of ω in the terminal region of storage modulus （G＇） versus ω plot. The ＂secondary plateau＂ appearing in the terminal region is attributed to the phase-separation of PMMA/SAN blends and it becomes more fiat for filled polymer blends under the same conditions. However, it is suggested that this kind of ＂induced effect＂ is related to the GB content; the higher content of GB particles might enhance the interaction between the particles and polymer matrix. Moreover, it is found that the addition of GB also has an influence more or less on the morphology and domain size of polymer matrix. It is believed that the plot of dynamic viscosity （η＇） versus the loss viscosity （η＂） is sensitive to examine the effect induced by GB on the phase-separation of binary polymer matrix.

Study on Electromagnetic Transient Condition of EMU Passing by Phase-separation with Electric Load in High-speed Railway

Aiming at the complex electromagnetic transient process of EMU passing by phase-separation with electric load in high-speed railway, mechanism of overvoltage caused by switching off, overvoltage caused by switching on and impact current is analyzed systematically in this article. π-type equivalent circuit of feeding section is put forward in the analysis of overvoltage mechanism. Overvoltage and overcurrent model of passing by phase-separation with electric load are also built. Correctness of mechanism was validated by simulation. In addition, the methods to solve the influence on substations, transformers and protection devices in this process are put forward, which provides a new idea on passing by phase-separation with electric load technology.

Increased excitatory amino acid transporter 2 levels in basolateral amygdala astrocytes mediate chronic stress–induced anxiety-like behavior

The conventional perception of astrocytes as mere supportive cells within the brain has recently been called into question by empirical evidence, which has revealed their active involvement in regulating brain function and encoding behaviors associated with emotions.Specifically, astrocytes in the basolateral amygdala have been found to play a role in the modulation of anxiety-like behaviors triggered by chronic stress. Nevertheless, the precise molecular mechanisms by which basolateral amygdala astrocytes regulate chronic stress–induced anxiety-like behaviors remain to be fully elucidated. In this study, we found that in a mouse model of anxiety triggered by unpredictable chronic mild stress, the expression of excitatory amino acid transporter 2 was upregulated in the basolateral amygdala. Interestingly, our findings indicate that the targeted knockdown of excitatory amino acid transporter 2 specifically within the basolateral amygdala astrocytes was able to rescue the anxiety-like behavior in mice subjected to stress. Furthermore, we found that the overexpression of excitatory amino acid transporter 2 in the basolateral amygdala, whether achieved through intracranial administration of excitatory amino acid transporter 2agonists or through injection of excitatory amino acid transporter 2-overexpressing viruses with GfaABC1D promoters, evoked anxiety-like behavior in mice. Our single-nucleus RNA sequencing analysis further confirmed that chronic stress induced an upregulation of excitatory amino acid transporter 2 specifically in astrocytes in the basolateral amygdala. Moreover, through in vivo calcium signal recordings, we found that the frequency of calcium activity in the basolateral amygdala of mice subjected to chronic stress was higher compared with normal mice.After knocking down the expression of excitatory amino acid transporter 2 in the basolateral amygdala, the frequency of calcium activity was not significantly increased, and anxiety-like behavior was obviously mitigated. Additionally, administration of an excitatory amino acid transporter 2 inhibitor in the basolateral amygdala yielded a notable reduction in anxiety level among mice subjected to stress. These results suggest that basolateral amygdala astrocytic excitatory amino acid transporter 2 plays a role in in the regulation of unpredictable chronic mild stress-induced anxiety-like behavior by impacting the activity of local glutamatergic neurons, and targeting excitatory amino acid transporter 2 in the basolateral amygdala holds therapeutic promise for addressing anxiety disorders.

Upgraded photometric system on the 85-cm telescope at Xinglong station

The 85-cm telescope at Xinglong station is a prime focus system that operates well with high science outputs. The telescope has been upgraded since 2014 with a new corrector, and new filters and camera, which are provided by Beijing Normal University. The filter set is the Johnson-Cousins UBV RI system. We report the test results of the new system including bias, dark current, linearity, gain and readout noise of the CCD camera. Then we derive accurate instrumental calibration coefficients in UBV RI bands with Landolt standard stars during photometric nights. Finally, we give the limiting magnitudes with various exposure times and signal-to-noise ratios for observers as references.

Inductively coupled plasma emission spectroscopic and flame photometric analysis of goat epididymal fluid

Aim: The elemental composition of the epididymal luminal fluid (ELF) in adult goat ( Capra indica) was investigat-ed. Methods: ELF was collected by micropuncture from twelve sites along the epididymal duct. The elementalcontents was analyzed with inductively coupled plasma (ICP) emission spectroscopy, a microanalytical technique thatcan simultaneously measure many elements in minute volumes of sample. The Na and K concentrations were determinedby flame photometry. Results: ICP spectroscopy showed the presence of copper, calcium, nickel, iron, magne-sium, chromium, titanium and zinc in ELF, with fluctuating levels at different sites along the length of the epididymis.Cadmium, cobalt, lead and manganese were not fotmd. The Na^+ / K^+ ratio was seen to be higher at the initial seg-ments of the epididymis and lower at the distal. Conclusion: It is proposed that the observed characteristic distribu-tion of elements in ELF may have far reaching implications in sperm maturation and storage known to occur in the epi-didymis. (Asian J Androl 2000 Dec; 2: 288-292)

The wide-field photometric system of the Nanshan One-meter Telescope

The Nanshan One-meter Wide-field Telescope is a prime focus system that is located at Nanshan Station of Xinjiang Astronomical Observatories.The field of view was designed to 1.5°× 1.5°,and the Johnson-Cousins UBVRI system was chosen as the main filter set.The telescope has been providing observation services for astronomers since September 2013.Variable source searching and time-domain surveys are the main scientific goals.The system’s test results are reported including linearity,dark current,bias,readout noise and gain of the CCD camera.The accurate instrumental calibration coefficients in UBVRI bands were driven with Landolt standard stars during photometric nights.Finally,the limiting magnitudes are given with signal-to-noise ratios and various exposure times for observers.

Photometric Survey of Galactic Open Clusters

We present a progress of a long term project to obtain UBVI CCD photometry of open clusters which were little studied before, using the Doyak 1.8 m telecope of Bohyunsan Optical Astronomy Observatory operated by the Korea Astronomical Observatory, in Korea. The primary goals of this project are (1) to make a catalog of UBVI photometry of open clusters, (2) to make an atlas of open clusters, and (3) to survey and monitor variable stars in open clusters.

Charge coupled devices （CCD） photometry and long-term optical variability of gamma-ray-loud BL Lacertae object Mkn 421

Evidence for the long-term optical curve variability and colour behaviour of the BL Lac object Mkn 421 is presented. Our results show that the amplitude of the optical variations of Mkn 421 is only about △B=4.7 magnitude in the B-band for its photometric history from 1899 to 2002. The results of optical photometric monitoring of the Mkn 421 from April 2000 to Jan 2002 are provided. During our observation, Mkn 421 shows significant rapid variations and exhibits short time variability of 2.42 hours in the B band. A strong correlation between the B - V colour index and the magnitude in the B band is found. Our charge coupled device （CCD） photometry of Mkn 421 shows that the measured results are in good agreement with the predicted optical variability period of about 23 years.

Thermoregulated Phase-separable Ru_3(CO)_(12)/PETPP Complex Catalyst for Hydrogenation of Styrene

Thermoregulated phase-separable Ru-3(CO)(12)/PETPP (PETPP=P[p-C6H4O (CH2CH2O)(n) H](3), n=6) complex catalyst was first applied in the hydrogenation of styrene. Under the conditions: P(H-2)=2.0MPa, T=90degreesC, styrene could be completely transferred and the yield of ethylbenzene reached up to 99.5%. After simple decantation, the catalyst could be reused for ten times without decreasing in activity.

All-fiber-transmission photometry for simultaneous optogenetic stimulation and multi-color neuronal activity recording

Manipulating and real-time monitoring of neuronal activities with cell-type specificity and precise spatiotemporal resolution during animal behavior are fundamental technologies for exploring the functional connectivity, information transmission, and physiological functions of neural circuits in vivo. However, current techniques for optogenetic stimulation and neuronal activity recording mostly operate independently. Here, we report an all-fiber-transmission photometry system for simultaneous optogenetic manipulation and multi-color recording of neuronal activities and the neurotransmitter release in a freely moving animal. We have designed and manufactured a wavelength-independent multi-branch fiber bundle to enable simultaneous optogenetic manipulation and multi-color recording at different wavelengths. Further, we combine a laser of narrow linewidth with the lock-in amplification method to suppress the optogenetic stimulation-induced artifacts and channel crosstalk. We show that the collection efficiency of our system outperforms a traditional epi-fluorescence system. Further, we demonstrate successful recording of dynamic dopamine(DA) responses to unexpected rewards in the nucleus accumbens(NAc) in a freely moving mouse. We also show simultaneous dual-color recording of neuronal Ca2+ signals and DA dynamics in the NAc upon delivering an unexpected reward and the simultaneous optogenetic activating at dopaminergic terminals in the same location. Thus, our multi-function fiber photometry system provides a compatible, efficient, and flexible solution for neuroscientists to study neural circuits and neurological diseases.

Studies on the Recycling Efficiency of Thermoregulated Phase-separable Rh/PETPP Complex Catalyst

Effects on the recycling efficiency of thermoregulated phase-separable Rh/PETPP (P-[p-C6H4O(CH2CH2O)nH]3, N=3n) complex catalyst involved in hydroformylation of 1-decene are for the first time presented. It was found that the loss of Rh is dependent greatly on the composition of phosphine ligand PETPP and the organic solvent employed in the reaction.

In vivo fiber photometry of neural activity in response to optogenetically manipulated inputs in freely moving mice

In vito fber photometry is a powerful technique to analyze the dy namics of population neurons during fiunctional study of neuroscience.Here,we introduced a detailed protocol for fiber photometry-based calciun reording in freely moving mice,covering from virus injection,fiber stub insertion,optogenetical stimulation to data procurement and analysis.Furthemnore,we applied this protocol to explore neuronal activity of mice latenal-posterior(LP)thalaric nucleus in response to optogenetical stimulation of primary visual cortex(V1)neurons,and explore axon clusters activity of optogenetically evoked V1 neurons.Final confirmation of virus-based protein expression in V1 and precise fber insertion indicated that the surgery procedure of this protocol is reliable for functional calcium recording.The scripts for data analysis and some tips in our protocol are provided in details.Together,this protocol is simple,low-cost,and effective for neuronal activity detection by fiber photometry,which will hep neuroscience researchers to carry out fiunctional and behavioral study in vivo.

The Simultaneous Three-channel Multicolor CCD Photometric System of the 1.2 m Telescope at Jilin Astronomical Observatory

We will introduce the construction and design of a new simultaneous three-channel multicolor CCD photometer.This photometer has been mounted on the 1.2 m telescope at Jilin Astronomical Observatory,and is applied to study space debris,gamma-ray burst afterglows,asteroids and other rapidly variable objects.As one of the ground follow-up telescopes of the Chinese-French Space-based multi-band astronomical Variable Objects Monitor(SVOM)mission,it appears very essential to evaluate the performance of the photometry system of this photometer,which can achieve simultaneous imaging within a field of view of 21’.5×21’.5,21’.5×21’.5 and21’.3×21’.3 in the Sloan Digital Sky Survey(SDSS)g’,r’,i’bands,respectively.Photometric calibrations were carried out by using plenty of SDSS standard stars,and the relationship between the photometric system and the Johnson-Bessel filter system was also studied.The results of the performance evaluation from observing open cluster M67 are presented.

Co-colouration Effects in the Systems of Metal(Ⅱ)-Rare Earth(Ⅲ)-Xanthene Dye and Their Influences on Photometric Determination of Metal Ions

After comparing the influences of each rare earth(Ⅲ),11 species of metal(Ⅱ)and 8 species of acidic triphenylmethane dye on the formation of coloured coordination compound in the system of Metal(Ⅱ)-RE (Ⅲ)-Dye,it was proven that the co-colouration effect can be caused only by the xanthene dyes(XD)con- taining substituting hydroxy.group on the ortho-position of etheric oxygen group.Besides,the radius of met- al(Ⅱ)must not be smaller than a definite limit;otherwise,no co-colouration appears.Furthermore,the acid- ity of medium is another important factor to affect co-colouration,Bromopyrogallol red causes co-colouration of Pb(Ⅱ)-RE(Ⅲ)only,owing to its higher chromophoric acidity;while alizarin violet causes co-colouration of M(Ⅱ)-RE(Ⅲ)(M=Pb,Ca,Sr and Ba),due to its lower chromophoric acidity.The condi- tions causing co-colouration,the regularities of co-colouration and the influences of co-colouration in photometric determination of metals were discussed.

Extraction-spectrophotometric Determination of Dicyanoaurate(Ⅰ) with Crystal Violet

Extraction spectrophotometric determination of dicyanoaurate (Ⅰ) with Crystal Violet is described. At pH 2.6～10.7, dicyanoaurate (Ⅰ) can react with Crystal Violet and form a complex which can be extracted into isoamylacetate. The apparent molar absorptivity is 8.37×10 4 L·mol -1 ·cm -1 at 605 nm. Beer′s law is obeyed for 0～15 μg of Au(Ⅰ) per 5 ml of isoamylacetate. The interference from Ag(Ⅰ) and Cu(Ⅱ) can be eliminated with thiourea and EDTA. The method is applied to the determination of dicyanoaurate (Ⅰ) in sample solution with satisfactory results.

Spectrophotometric Methods for Simultaneous Determination of Amlodipine Besylate and Atenolol in Their Tablet Dosage Form

Three simple,specific,accurate and precise spectrophotometric methods are developed for simultaneous determination of amlodipine besylate(AM)and atenolol(AT)in tablets.The first method is dual wavelength spectrophotometry(DW).The second method is ratio subtraction(RS)which depends on subtraction of the plateau values from the ratio spectrum,coupled to first derivative of ratio spectra(1 DD).The third method applies bivariate calibration method using 210and 225nm as an optimum pair of wavelength for amlodipine and atenolol.The calibration curves are linear over the concentration range of 4~40μg·mL-1 for both drugs.The specificity of the developed methods is investigated by analyzing laboratory prepared mixtures of the two drugs and their combined dosage form.The two methods are validated as per ICH guidelines and can be applied for routine quality control testing.

Color-Redshift Relations and Photometric Redshift Estimations of Quasars in Large Sky Surveys

With a recently constructed composite quasar spectrum and the χ2 minimization technique, we describe a general method for estimating the photometric redshifts of a large sample of quasars by deriving theoretical color-redshift relations and comparing the theoretical colors with the observed ones. We estimated the photometric redshifts from the 5-band SDSS photometric data of 18678 quasars in the first major data release of SDSS and compared them with their spectroscopic redshifts. The difference is less than 0.1 for 47 % of the quasars and less than 0.2 for 68 %. Based on the calculation of the theoretical color-color diagrams of stars, galaxies and quasars both on the SDSS system and on the BATC system, we expect that we would be able to select candidates of high redshift quasars more efficaciously with the latter than with the former, provided the BATC survey can detect objects with magnitudes fainter than 21.

Preliminary Study of Photometric Redshifts Based on the Wide Field Survey Telescope

The Wide Field Survey Telescope(WFST)is a dedicated time-domain multi-band(u,g,r,i,and z)photometric survey facility under construction.In this paper,we present a preliminary study that assesses the quality of photometric redshifts based on WFST by utilizing mock observations derived with the galaxy catalog in the COSMOS/UltraVISTA field.We apply the template fitting technique to estimate photometric redshifts by using the ZEBRA photometric-redshift code and adopting a modified set of adaptive templates.We evaluate the bias(median relative offset between the output photometric redshifts and input redshifts),normalized median absolute deviation(σ_(NMAD))and outlier fraction(f_(outlier))of photometric redshifts in two typical WFST observational cases,the single 30 s exposure observations(hereafter shallow mode)and co-added 50 minutes exposure observations(hereafter deep mode).We find bias≲0.006,σ_(NMAD)≲0.03,and f_(outlier)≲5%in the shallow mode and bias≈0.005,σ_(NMAD)≈0.06,and f_(outlier)≈17%–27%in the deep mode,respectively,under various lunar phases.Combining the WFST mock observational data with that from the upcoming CSST and Euclid surveys,we demonstrate that the zphot results can be significantly improved,with f_(outlier)≈1%andσ_(NMAD)≈0.02.

Photometric Redshifts and Galaxy Clusters for DES DR2, DESI DR9, and HSC-SSP PDR3 Data

Photometric redshift(photoz)is a fundamental parameter for multi-wavelength photometric surveys,while galaxy clusters are important cosmological probes and ideal objects for exploring the dense environmental impact on galaxy evolution.We extend our previous work on estimating photoz and detecting galaxy clusters to the latest data releases of the Dark Energy Spectroscopic Instrument(DESI)imaging surveys,Dark Energy Survey(DES)and Hyper Suprime-Cam Subaru Strategic Program(HSC-SSP)imaging surveys and make corresponding catalogs publicly available for more extensive scientific applications.The photoz catalogs include accurate measurements of photoz and stellar mass for about 320,293and 134 million galaxies with r<23,i<24 and i<25 in DESI DR9,DES DR2 and HSC-SSP PDR3 data,respectively.The photoz accuracy is about 0.017,0.024 and 0.029 and the general redshift coverage is z<1,z<1.2 and z<1.6,respectively for those three surveys.The uncertainty of the logarithmic stellar mass that is inferred from stellar population synthesis fitting is about 0.2 dex.With the above photoz catalogs,galaxy clusters are detected using a fast cluster-finding algorithm.A total of 532,810,86,963 and 36,566 galaxy clusters with the number of members larger than 10 is discovered for DESI,DES and HSC-SSP,respectively.Their photoz accuracy is at the level of 0.01.The total mass of our clusters is also estimated by using the calibration relations between the optical richness and the mass measurement from X-ray and radio observations.The photoz and cluster catalogs are available at Science DB(https://www.doi.org/10.11922/sciencedb.o00069.00003)and Paper Data Repository(https://doi.org/10.12149/101089).