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As a novel X-ray focusing technology, lobster eye micro-pore optics (MPO) feature both a wide observing field of view and true imaging capability, promising sky monitoring with significantly improved sensitivity and spatial resolution in soft X-rays. Since first proposed by Angel (1979), the optics have been extensively studied, developed and trialed over the past decades. In this Letter, we report on the first-light results from a flight experiment of the Lobster Eye Imager for Astronomy ($LEIA$), a pathfinder of the wide-field X-ray telescope of the Einstein Probe mission. The piggyback imager, launched in July 2022, has a mostly un-vignetted field of view of $18.6^\circ \times 18.6^\circ $. Its spatial resolution is in the range of 4$-$7 arcmin in FWHM and the focal spot effective area is 2$-$3 cm$^2$, both showing only mild fluctuations across the field of view. We present images of the Galactic center region, Sco X-1 and the diffuse Cygnus Loop nebular taken in snapshot observations over 0.5$-$4 keV. These are truly wide-field X-ray images of celestial bodies observed, for the first time, by a focusing imaging telescope. Initial analyses of the in-flight data show excellent agreement between the observed images and the on-ground calibration and simulations. The instrument and its characterization are briefly described, as well as the flight experiment. The results provide a solid basis for the development of the present and proposed wide-field X-ray missions using lobster eye MPO., Comment: 11 pages, 4 figures. Accepted for publication in Astrophysical Journal Letter

Cervical cancer is the fourth common cancer in women globally, with the number of new cases accounted for 18.6宫颈癌是全球女性第四大常见恶性肿瘤，我国发病人数占全球的18.6

Endotoxin lipopolysaccharide (LPS) affects the ruminant health and animal performance. The main purposes of this study were to investigate the potential effects of GH/IGF system and lipoprotein lipase (LPL) concentration on resistance the circulating LPS concentration increased in liver with high concentrate diet treatment. Non-lactating goats were randomly allocated to two groups: a high-concentrate diet (HCD) or a low-concentrate diet (LCD) in cross over design and the blood collection at different time points after feeding at the end of the experiment. The average rumen pH was significantly reduced (P

A new type of power source is proposed, which is based on the traffic signal matching method of the dual energy source power supply composed of the batteries and the supercapacitors. First, analyzing the power characteristics is required to meet the excellent dynamic characteristics of EV, studying the energy characteristics is required to meet the mileage requirements and researching the physical boundary characteristics is required to meet the physical conditions of the power supply. Secondly, the parameter matching design with the highest energy efficiency is adopted to select the optimal parameter group with the method of matching deviation. Finally, the simulation analysis of the vehicle is carried out in MATLABSimulink, The mileage and energy efficiency of dual energy sources are analyzed in different parameter models, and the rationality of the matching method is verified.

Objective: The objectives of this study are to understand the current functions, structure and operation of hospital ethics committees (HECs) in Shanghai and to facilitate their improvement. Methods: (1) A questionnaire survey, (2) interviews with secretaries and (3) on-site document reviews of HECs in Shanghai were used in the study, which surveyed 33 hospitals. Results: In Shanghai, 57.56% of the surveyed hospitals established HECs from 1998 to 2005. Most HECs used bioethical review of research involving human subjects as well as bioethical review or consultation regarding medical care services and administrative decision- making. Of the surveyed HECs, 14.3% did not provide any formal bioethical training to the HECs’ members and many HECs had no standard operating procedures. Some HECs had no clear definition of what was “conflict of interest” that should be considered by the HECs, while 44.4% of the HECs did not perform continuing review. Discussion: After the issues of related national regulations, more and more hospitals established HECs in Shanghai, but the functions of HECs need to be further developed and formal training on bioethics should be provided to HEC members. To assure the independence and good performance of HECs, the conflict of interest procedure, the standard operating procedures and bioethical review should be improved. Conclusion: HECs in Shanghai had developed in the preceding 10 years and they played great roles in protecting the rights and welfare of human subjects and patients; some areas need improvement.

The damage behavior of laminated E-glass/epoxy beams, with and without an initial delamination, subjected to an axial impact by a moving bullet has been investigated experimentally and numerically. The specimens were made from a unidirectional fiber fabric stacked in the sequences [06] s , [±453] s , and [906] s , and a delamination was created in them by locating a copper foil at a specified position. The data on the bullet speed and strain history were recorded by a laser setup, a high-speed dynamic strain indicator, and a TDS420A oscilloscope. It is shown that the delamination and the ply stacking sequence play a significant role in the dynamic response and damage behavior of laminated beams. A numerical simulation is performed by using the commercial finite-element software ABAQUS/Explicit, and the results obtained are in a good agreement with experimental observations.

A dynamic model for estimating position of ship towed array during U-turn manoeuvre is introduced and developed. Based on this model, the influences of the parameters such as time step and segment length on the numerical simulation are analysed. The results indicate that decreasing the time step has little effect on the simulation accuracy but will increase the computational time. The selection of segment length has a great influence on the estimation of ship towed array position during U-turn manoeuvre. Reducing the segment length somewhat increases the computational complexity and significantly improves simulation precision.

Excimer laser doping of GaAs using sulphur adsorbate as a dopant source is demonstrated. Box-like n-type layers of depths of about 100 nm with carrier concentration as high as (2∼3)×1019 cm−3 are formed. Passivation of GaAs using a (NH4)2Sx solution for 40 min followed by sublimation of the excess sulphur atoms in high vacuum result in an effective dopant for controllable n-type doping. The samples are irradiated using a KrF excimer laser in a N2 gaseous environment. Secondary ion mass spectrometry (SIMS) measurements show that sulphur is successfully incorporated in the GaAs. The sheet resistance is controlled by adjusting the laser energy fluence and number of laser pulses. Rutherford backscattering spectrometry with channeling (RBS/C) alignment measurement indicates that lattice damage is undetectable for N2 gas pressures of 760 Torr.

Photocurrent spectra of doped black silicon (BSi) samples were investigated using metal-semiconductor-metal (MSM) structure. The BSi samples were fabricated through femtosecond-laser doping method. Two pieces of samples were annealed in nitrogen ambient for 30 minutes at different temperatures 350°C and 700°C. One control sample remains without annealing. It was found that the doped black silicon samples have an electron mobility as low as 40~50 cm 2 /V s but a conductivity as high as 4 ~ 5 Scm -1 . The high conductivity allows making electrodes by directly contacting metal stripes onto the black silicon surfaces. For the sample without annealing, its photocurrent spectrum covers a wavelength range from 400 nm to 1200 nm. For the sample annealed at 350°C, no significant improvement was found except disappearance of a defect induced photocurrent peak at 660 nm. Further annealing at 700°C, as observed for the third sample, was found to greatly help enhance photoresponse in the wavelength range from 400 nm to 800 nm. The photocurrent spectra under different biases were also measured. With the increasing of bias from 0 to 0.6 V, the peak photoresponse was enhanced by about 5 times while large dark current brought in substantial noise level as well.

Digitized description of rock is one trend of flow modeling. The paper presents a method for reconstructing 3D network model of microscopic pore structure according to CT images of rock. Sequential CT images which can fully describe 2D microscopic pore structure of rock are obtained by using ACTIS-225FFi CT/DR/RTR microfocus CT equipment. 3D skeleton and pore-bodies of the porous media can be obtained through processing these images by using the thinning algorithm. On the base of analyzing the differences between the core model and the network model, pores and throats are extracted considering the geometrical equivalence through equivalent method of flow conductivity and shape factor. Thus, the conversion from CT scanned images of real rock into a 3D network model is realized, which can be used as a powerful tool in flow simulation. One advantage of the method lies in the fact that simplified geometrical objects, such as pores and throats, can be used to replace the irregular geometry with less calculating time while retaining the geometrical features and flow characters. Based on the method above mentioned, the paper takes well 70-1 of Kendong oilfield, China as an example to carry out the CT scanning experiment and to reconstruct the network model. It is found that there is a good agreement between the calculated parameters of network model and those of porosity, absolute permeability, capillary pressure curves as well as relative permeability curve measured in laboratory, which indicates that the network model can fully describe the microscopic pore and throat sizes as well as topology of rock.

To clone and analyze novel antigen molecules of Schistosoma japonicum (Sj), and to provide effective vaccine candidate antigens against schistosomiasis japonica.Sj adult cDNA library was screened using sera of mice infected with Trichinella spiralis (Ts) and the inserts of positive clones were specifically amplified by PCR. The positive clones were sequenced and the sequence data were analyzed using Nucleotide BLAST software of NCBI and Expert Protein Analysis System of Swiss Institute of Bioinformatics.Nine positive clones were obtained after three rounds of immunoscreening. The size of these inserts ranged from 0.6 kb to 2.1 kb. Among five novel genes, Sj-Ts1, Sj-Ts3 and Sj-Ts5 (GenBank accession number: AY005816, AF299080 and AY024352, respectively) encode trans-membrane proteins with 83, 83 and 233 amino acids, respectively. Sj-Ts1 protein predicted contains one possible trans-membrance helix, one N-myristoylation site, two phosphorylation sites for protein kinase C and one for tyrosine kinase, Sj-Ts3 protein contains two possible transmembrance helices and one casein kinase II phosphorylation site, whereas Sj-Ts5 protein has five possible transmembrance helices, one N-glycosylation site, one N-myristoylation site, two phosphorylation sites for cAMP- and cGMP-dependent protein kinase and four for protein kinase C and one for casein kinase II.Three novel genes encoding three transmembrane proteins might be developed as new vaccine candidates against Sj infection.

To evaluate the specificity and sensitivity of SjMAg in detecting specific antibodies in sera of patients with schistosomiasis japonica and in assessing therapeutic efficacy.SjMAg-ELISA was used to determine the specific IgG and IgG4 in sera of patients with schistosomiasis japonica at different time points after chemotherapy.SjMAg-ELISA was as sensitive and specific as SEA-ELISA. The negative conversion rate of IgG detected by SjMAg-ELISA 12 months after treatment was 80.0%, being significantly higher than 43.3% by SEA-ELISA. The negative conversion rate of IgG4 detected by SjMAg-ELISA 12 months after treatment was 93.3%, being significantly higher than 60.0% by SEA-ELISA. The negative conversion rates of IgG and IgG4 2 yr after treatment were 92.9% and 97.6% respectively.SjMAg-ELISA is comparable to SEA-ELISA in diagnosing schistosomiasis japonica and is more effective in assessing therapeutic efficacy.

Thirty-three egg-positive subjects and 32 egg-negative subjects were tested synchronously by KLH-IDT and SEA-IDT in endemic area of schistosomiasis. Compared with stool examination, the positive coincidence rate of KLH-IDT and SEA-IDT were 90% and 100%, respectively, which showed no statistical significance(P0.05), and the negative coincidence rate of KLH-IDT and SEA-IDT were 71.9% and 25%, respectively, which showed statistical significance(P0.01). Of the 31 egg-negative subjects, 9 subjects showed positive by both SEA-IDT and KLH-IDT, and 15 subjects showed positive by SEA-IDT but negative by KLH-IDT. Both double positive subjects and single positive subjects were examined further by miracidium hatching test, there were 2 subjects showing positive among the 9 double positive subjects. In addition, of 27 subjects that had been treated one year before, only 6 subjects showed positive by KLH-IDT, the reversion rate was 77.8%; whereas, the reversion rate was 22.2% (6/21) by SEA-IDT. The results suggest that KLH-IDT has high value in diagnosing schistosomiasis, particularly shows a potential in assessing therapeutic efficacy of schistosomiasis.

Optical parametric chirped pulse amplification has apparent advantages over the current schemes for high energy ultrashort pulse amplification. High gain in a single pas amplification, small B-integral, low heat deposition, high contrast ratio and, especially the extremely broad gain bandwidth with large-size crystals available bring people new hope for over multi-PW level at which the existing Nd:glass systems suffered difficulties. In this paper we present simulation and experimental studies for a high gain optical parametric chirped pulse amplification system which may be used as a preamplifier to replace the current complicated regenerative system or multi-pas Ti:sapphire amplifiers. Investigations on the amplification pump and chirped broadband pulse as a seed, respectively. Analysis and discussions are also given.

In this paper an electromagnetically pumped free-electron- laser (FEL) with a tampered guide magnetic field is investigated by solving the Vlasov-Maxwell equations. The linear and nonlinear dispersion relations are derived. The nonlinear dispersion relation is solved to obtain the growth rate of the FEL. The energy conversion efficiency is estimated. The results show that the growth rate and the energy conversion efficiency for this kind of FEL may be obviously enhanced by adding a tapered guide magnetic field properly.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Etching experiments were performed on (0001) oriented tellurium single crystal samples irradiated with a CO2 laser beam to reveal the localized induced dislocations in the crystals. It was found that the tellurium surface is very sensitive to the laser beam. Under low illumination intensity, visible defects were not found but the dislocation density was greatly increased. Under high illumination intensity, visible damage on the surface was observed; the surface was found to be locally remelted by the laser beam to result in a hole with many cracks around it.