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Purpose The physics design of the High Energy Photon Source (HEPS) was finished after many times of iteration. Hereby, the typical equilibrium electron beam parameters corresponding to the proposed two baseline operation modes in the baseline design of HEPS are presented. Methods To compute the equilibrium parameters of the electron beam, the lattice parameters, RF parameters, and the parameters of the insertion devices (IDs) were determined first. Furthermore, it is more precise to use the full-current electron beam parameters in the estimations of the performance of the synchrotron light. Therefore, not only the single-particle dynamics but also the current-dependent collective effects need to be considered in the computations of the full-current, equilibrium parameters of the electron beam. Both analytic computations and multi-particle tracking simulations were carried out. Results The full-current, equilibrium parameters of the electron beams in the HEPS storage ring are presented in this paper. Moreover, the main beam parameters in the injector (the booster and the LINAC), corresponding to the two baseline operation modes of the storage ring, are also presented. Conclusion The typical electron beam parameters corresponding to the two baseline operation modes are given in detail in this paper.

As the current society is increasingly facing major challenges from extremism and terrorism, protecting key urban public facilities and important targets from destruction is an important challenge facing the security departments of all countries. Based on real scene, this paper conducts researches on anti-terrorism security game algorithms and emergency response models in response to the three key links of before, during and after terrorist attacks. First of all, this paper constructs a multi-round joint attack game and emergency response model based on cooperation, establishes the optimization problem of solving the defender’s optimal strategy in mathematical form, and then obtains the optimal defense strategy. Secondly, in response to the fact that terrorists are not completely rational, a new hybrid model is constructed to propose an efficient allocation and scheduling algorithm for safe resources in response to terrorist attacks. Thirdly, a model of crowd evacuation strategy after a terrorist attack is built based on the problem of crowd evacuation in multiple rounds of premeditated cooperative attacks. Finally, taking the area of the first ring of a certain city as a real scene, a complete game system of the whole process is constructed, and the game effectiveness evaluation of the existing security resource allocation scheme in the first ring area is carried out. Through the research of this thesis, the author puts forward some new technical ideas for the current society’s anti-terrorism governance, and hopes to provide some technical references for the decision-making of security agencies.

Idiopathic pulmonary fibrosis (IPF) is a progressive fibrotic disease with poor prognosis. Evidence has shown that vimentin is a key regulator of lung fibrogenesis. 99mTc-labeled N-acetylglucosamine-polyethyleneimine (NAG-PEI), a vimentin-targeting radiotracer, was used for the early diagnosis of IPF, and NAG-PEI was also used as a therapeutic small interfering RNA (siRNA) delivery vector for the treatment of IPF in this study. Single-photon emission-computed tomography (SPECT) imaging of bleomycin (BM)- and silica-induced IPF mice with 99mTc-labeled NAG-PEI was performed to visualize pulmonary fibrosis and monitor the treatment efficiency of siRNA-loaded NAG-PEI, lipopolysaccharide (LPS, a tolerogenic adjuvant), or zymosan (ZYM, an immunostimulant). The lung uptakes of 99mTc-NAG-PEI in the BM- and silica-induced IPF mice were clearly and directly correlated with IPF progression. The lung uptake of 99mTc-NAG-PEI in the NAG-PEI/TGF-β1-siRNA treatment group or LPS treatment group was evidently lower than that in the control group, while the lung uptake of 99mTc-NAG-PEI was significantly higher in the ZYM treatment group compared to that in the control group. These results demonstrate that NAG-PEI is a potent MicroSPECT imaging-guided theranostic platform for IPF diagnosis and therapy.

Riboflavin transporter-3 (RFVT3) is a recently discovered and novel biomarker for the theranostics of nervous system diseases. RFVT3 is significantly overexpressed in cerebral injury after ischemic stroke. Herein, we first reported an RFVT3-targeted tracer

Superconducting 499.8-MHz radio frequency (rf) cavities have been proposed for the High Energy Photon Source (HEPS), a 6-GeV diffraction-limited synchrotron light source currently under construction in Beijing. Being an active third-harmonic system, two cavities shall provide 3.5-MV rf voltage and 400 kW of beam power to enable a complex rf gymnastics required by a novel injection scheme. Adopting the veteran KEKB-type 500-MHz single-cell geometry, the cavity design has been focused on optimizing its mechanical properties. Various cavity wall thickness and external stiffening mechanisms were investigated to reinforce the cavity to ensure compliance to the pressure vessel codes under different working conditions from a bare cavity to a dressed cavity in the cryomodule. Small margins on operational pressure previously reported on this type of cavity have been largely improved with slightly reduced yet acceptable frequency tunability. Extensive design optimizations have been conducted aiming for lower stress, larger elastic buckling pressure, and higher frequencies of mechanical modes to cause microphonics, while the frequency tunability, pressure sensitivity, and Lorentz force detuning were being carefully monitored. In view of the HEPS’s lifetime, cavity fatigue was examined. This constitutes a comprehensive design optimization of the 499.8-MHz single-cell superconducting cavity with improved mechanical properties.

Superconducting β=1 quarter-wave geometry of 166.6 MHz has been proposed as main accelerating cavities for the high-energy photon source (HEPS) storage ring. HEPS is a 6-GeV kilometer-scale synchrotron light source promising ultralow emittance currently being constructed in Beijing. A proof-of-principle cavity has been previously in-house developed and vertical-tested achieving excellent cryogenic performances. A helium jacket was subsequently designed adopting a simple structure and an integrated magnetic field shielding. The mechanical properties of the dressed cavity were largely improved focusing on pressure sensitivity, stress, and Lorentz force detuning, while frequency tunability and microphonics were carefully monitored. Elastic buckling and fatigue were also examined. The helium jacket was later fabricated and welded directly with the niobium cavity. Mounted with an input power coupler and tuners, the dressed cavity was finally assembled in a modified cryomodule and tested at both 4.2 and 2.0 K. The favored low-pressure sensitivity and small Lorentz force detuning were confirmed. Microphonics spectrum was scanned and measured, presenting good consistencies with simulation predictions. Finally, the cavity was successfully tuned to the operating frequency of 166.6 MHz at cold and its frequency could be regulated within a ±3-Hz range. This article covers the mechanical aspects in the development and horizontal cryogenic tests of the first dressed 166.6-MHz superconducting cavity.

A reliable and repeatable post-processing technology of improving the performance of 1.3 GHz superconducting radio frequency (SRF) cavities is one of the critical technologies for the ILC and XFEL and ERL projects. Three 1.3 GHz single-cell cavities were fabricated and received a baking in temperature 330 °C, while the interior of the cavity stayed in ultra-high vacuum (UHV). The cavities were also vertical-tested after electropolishing (EP) with 120 °C 48-h baking and with nitrogen doping separately for a comparison. The Q0 of 1.3 GHz single cavity after medium-temperature baking can be 2–3 × 1010 in the accelerating gradient range of 2–35 MV/m in the 2 K vertical test in IHEP. Meanwhile, the outer surface oxidation of niobium cavity caused by baking will decrease the performance of the SRF cavity. Medium-temperature (250–400 °C) baking on the 1.3 GHz single-cell cavity will improve its Q0 in 2 K vertical test compared with EP followed by 120 °C 48-h baking baseline and reach a similar level of nitrogen doping, and the quench field will lower to a typical range of 20–30 MV/m. Meanwhile, the cavity performance is sensitive to the baking time and temperature, which indicates that a tremendous improvement can be made on the current treatment.

The Arabidopsis thaliana atypical Cys His-rich thioredoxins (ACHTs) are a small class of atypical thioredoxins (TRXs) located in chloroplasts thylakoids and are characterized by a noncanonical motif at their redox active site, C (G/S)(S/G)C. Previous studies have reported that ACHT1 can interact with A. thaliana 2-Cys peroxiredoxins (2-Cys Prxs, including PrxA and PrxB) to transmit oxidation signals in response to illumination with normal light intensity. In this study, we reported the crystal structure of ACHT1 and show that ACHT1 adopts a canonical TRX fold. Comparison of the structures of ACHT1 in both reducing and oxidizing environments revealed that while the redox environment did not influence the overall structure of ACHT1, it did change the conformation of its catalytic residues. We found that the catalytic C125 of ACHT1 is the target residue for PrxA in vitro. In addition, we found that ACHT1 can reduce the peroxidase activity of PrxA, and further confirmed that the ability of ACHT1 to restore the peroxidase function of PrxA was due to the interaction between the two. Our results provide a structural basis for studying the function of atypical TRXs and the oxidative regulation mechanism of ACHT1 and 2-Cys Prxs in chloroplasts.

Carotenoid metabolism is critical for diverse physiological processes. The nematode Caenorhabditis elegans has two genes that are annotated as β-carotene 15,15′-monooxygenase (BCMO) and are 17 centimorgan apart on chromosome II, but the function of BCMO-1 and BCMO-2 remains uncharacterized. Sequence homology indicates that the two enzymes belong to the carotenoid cleavage dioxygenase family that share a seven-bladed β-propeller fold with a nonheme iron center. Here we determined crystal structures of BCMO-1 and BCMO-2 at resolutions of 1.8 and 1.9 Å, respectively. Structural analysis reveals that BCMO-1 and BCMO-2 are strikingly similar to each other. We also characterized their β-carotene cleavage activity, but the results suggest that they may not act as β-carotene 15,15′-oxygenases.

Introduction Hypertension, one of the most common chronic diseases worldwide, usually requires lifetime managing blood pressure (BP) with medications. Due to quite large number of hypertension patients co-exist with depression and/or anxiety, and non-cooperated with medical instruction, consequently management of BP is impaired with serious complications, resulting in compromised quality of life. Consequently quality of life of such patients is impaired with serious complications. Therefore, management of depression and/or anxiety is equally important as the treatment of hypertension. Depression and/or anxiety are independent risk factors of hypertension, which is supported by the finding that there is close correlation between hypertension are depression/or anxiety. Psychotherapy (non-drug treatment) maybe useful for hypertensive patients with depression and/or anxiety to improve their negative emotions. We aim to quantify the effective of psychological therapies in the management of hypertension patients with depression or anxiety, by comparing and ranking a network meta-analysis (NMA). Materials and methods Literature search for randomized controlled trials (RCTs) will be performed in five electronic databases from inception to December 2021, including PubMed, the Cochrane library, Embase, Web of Science, and China Biology Medicine disc (CBM). The search terms mainly include “hypertension”, “mindfulness-based stress reduction” (MBSR), “cognitive behavioral therapy” (CBT) and “dialectical behavior therapy” (DBT). Cochrane Collaboration quality assessment tool will be used for the risk of bias assessment. A Bayesian network meta-analysis will be performed, using WinBUGS 1.4.3, and Stata 14 will be applied to draw the network diagram, while RevMan 5.3.5 will be used to produce funnel plot for assessing the risk of publication bias. Recommended rating, development and grade methodology will also be utilized to assess the quality of evidence. Results Effect of MBSR, CBT and DBT will be evaluated by traditional meta-analysis directly and Bayesian network meta-analysis indirectly. Our study will provide the evidence on the efficacy and safety of psychological treatments in the hypertension patients with anxiety. There is no research ethical requirement because this is a systematic review of published literature. The results of this study will be published in a peer-reviewed journal. Trial registration Prospero registration number: CRD42021248566.

Carotenoid metabolism is critical for diverse physiological processes. The nematode

Idiopathic pulmonary fibrosis (IPF) is a progressive fibrotic disease with poor prognosis. Evidence has shown that vimentin is a key regulator of lung fibrogenesis.

Objective: To determine the relationship between the health literacy of patients with diabetes mellitus (DM) and the accessibility of internet surfing for information concerning DM.Methods: A multistage stratified sampling method was utilized to conduct a questionnaire survey on DM health literacy and internet accessibility among 1,563 patients with DM in Gansu Province in 2020. Logistic regression was performed to analyze the factors that influence health literacy and internet accessibility; while the chi-square test was used to compare the differences in needs.Results: Among 1,563 valid questionnaires collected with an effective rate of 95.7%, there were 65.4, 66.3, or 51.1% of patients with DM were found to have good health knowledge, attitudes, or practice levels, respectively. Occupation, income, disease course of DM, and accessibility to the internet were the main factors influencing health literacy. Age, residency, occupation, education, income, and family history of DM were the factors influencing accessibility to internet surfing for DM. The expectations from patients with DM for the capacity to obtain DM information from traditional sources or through internet sources was 1,465 (93.7%) or 1,145 (73.3%), respectively. Patients with DM had a 2-fold higher desire to obtain DM health information from internet media if the patients had access to the internet than those without (P < 0.05).Conclusions: The socioeconomic status and access to the internet were the main contributing factors for health literacy, as socioeconomic status is closely related to access to the internet.

The 10-MeV Accelerator-Driven Subcritical (ADS) system Injector-I test stand at the Institute of High Energy Physics (IHEP) is a testing facility dedicated to demonstrating the feasibility of the spoke-based superconducting (SC) linear accelerator (linac) for the ADS project in China. The injector adopted a four-vane copper structure radio frequency quadrupole (RFQ) with an output energy of 3.2 MeV and an SC section accommodating 14 $$\beta _{\text{g}}$$ =0.12 single spoke cavities, 14 SC solenoids, and 14 cold beam position monitors (BPMs). A 10-MeV pulsed beam with a beam current of 10 mA and a 2-mA continuous wave (CW) beam were successfully shooting through. The commissioning results confirmed the feasibility of using a 325-MHz spoke-type cavity for accelerating the proton beam in the low $$\beta$$ and medium $$\beta$$ sections. This paper describes the results achieved, the difficulties encountered, and the experiences obtained during commissioning.

The nitrogen doping/infusion of 650 MHz cavities for the circular electron positron collider (CEPC) is investigated in this study. Two 650 MHz 1-cell cavities are first treated via buffered chemical polishing (BCP), followed by nitrogen doping. A “2/6” condition is adopted, similar to that for 1.3 GHz cavities of Linear Coherent Light Source II. The quality factor of both cavities improved to 7 × 1010 in low fields, i.e., higher than that obtained from the baseline test. One 650 MHz two-cell cavity is nitrogen infused at 165 °C for 48 h with a BCP surface base. The intrinsic quality factor (Q0) reached 6 × 1010 at 22 MV/m in the vertical test, and the maximum gradient is 25 MV/m, which exceeds the specification of the CEPC (4 × 1010 at 22 MV/m).

The fluctuation of stock market is affected by many factors, such as human psychology, macro-economy, operation state of listed companies and industry. These factors can be regarded as risk factors that affect the excess return of stocks. According to the Arbitrage Pricing Theory, excess return and risk are closely related, and the excess return of stock is brought by taking certain risks. With the development of Chinese stock market, more and more risk factors that affect stock return are quantified. Among them, technical factors and fundamental factors are the most important two categories. Technical factors mainly reflect the trend of stock price and the trading activity of the market. Fundamental factors mainly reflect the operation and profitability of listed companies. These two kinds of factors are also the most commonly used in the quantitative model. Based on these two kinds of factors, we proposed a two branch risk factors model, which can combine these two kinds of factors to select stocks.

Sina Weibo is an ideal place to spread rumors in China, and automatic debunking rumor is a crucial problem. To detect rumors, the rumors detection method based on deep learning adopts the static pretraining model for text representation. After word vector training, it will not change any more, and there are the problems that the vector cannot represent the polysemy of words in different contexts. In order to solve this problem, this paper presents a novel method that rumors detection based on Bert-GRU and proposes an implementation method using the Bert model for the microblog text representation, while using the gated recurrent unit (GRU) networks to learn features for rumors detection. Experimental results show that the proposed method has a good effect on detecting rumors in Weibo.

In the field of natural language processing, traditional machine learning methods rely on a large amount of labeled data to obtain better results and require training data and test data to satisfy the assumption of independent and identically distributed. Application of transfer learning technology provides a good solution to the problems above and promotes the research progress of natural language processing. This paper studied the application of transfer learning in natural language processing, made the definition of transfer learning, classified the transfer learning in natural language processing, and prospected the development of transfer learning in natural language processing.

As the development of social networks has promoted scientific research in various fields, the Sina Weibo platform has become popular with users because of its real-time information and has become a new communication method and research tool for public opinion topics. The key audience groups of Weibo topics have an important influence on public opinion, so the research on key audience groups of Weibo hot topics has become one of the main contents of public opinion analysis. The research focuses on the characteristics of Weibo social platforms and the relationship between participants and forwarders in popular topics on Weibo. On the one hand, the main improvement’s overreliance on algorithms makes it impossible to achieve the greatest impact on scalability. By combining data driving with machine learning, some practical improvements are made. On the other hand, to improve the quality of the seed set for maximizing the impact of propagation impact prediction, a multi-dimensional Weibo audience user influence maximization measurement algorithm maximize your influence (MYI) is proposed. The experimental results show that the MYI algorithm can more fully identify the main audience groups in information dissemination and play an extremely important role in guiding public opinion.

166.6-MHz quarter-wave $$\beta =1$$ superconducting cavities have been adopted for the High Energy Photon Source, a 6-GeV diffraction-limited synchrotron light source currently under construction. A large helium jacket was required to accommodate the enlarged cavity beam pipe for the heavy damping of higher-order modes; the original electric-probe pickup thus becomes inevitably long with unfavorable mechanical properties. Relocated to an existing high-pressure-rinsing port, a magnetic-loop pickup was designed, characterized by low radio-frequency and cryogenic losses and being multipacting-free and insensitive to manufacturing and assembly tolerances. The consequent removal of the original pickup port from the cavity largely simplified the helium jacket fabrication and may also reduce cavity contamination. This paper presents a comprehensive design of a low-loss magnetic-coupling pickup for quarter-wave $$\beta =1$$ superconducting cavities. The design can also be applied to other non-elliptical structures.

Superconducting 166.6 MHz β = 1 cavities of quarter-wave geometry have been chosen for a high energy photon source, a 6 GeV diffraction-limited synchrotron light source currently under construction in Beijing. Five cavities will provide the required 5.4 MV radio frequency (rf) voltage and 900 kW beam power. Each cavity will be equipped with one fundamental power coupler (FPC), delivering a minimum rf power of 180 kW to the beam. A 50 Ω coaxial structure with one planar warm window was employed. Its location was carefully selected to avoid electron bombardments on the ceramic window due to potential cavity field emission while preserving the required strong coupling. Focusing on optimized heat loads, a compact geometry was pursued to allow assembly with the cavity in a class 10 clean room, thus minimizing contamination. Two prototype FPCs have been fabricated and examined with high power on room-temperature test stands. The couplers were tested up to 50 kW continuous wave (cw) limited by the available solid-state amplifier. The rf conditioning was conducted initially in travelling-wave mode and later in a standing-wave setup with the variable phase of the reverse wave. All rf surfaces were thus exposed to a high field equivalent to 200 kW cw traveling wave. Being the most critical component, the window-inner-conductor assembly was conditioned up to 150 kW at 650 MHz on a hybrid test stand. Multipacting barriers were encountered as predicted and can be processed by rf conditioning. The design, fabrication, and high-power tests of the first 166.6 MHz FPCs are presented.

Medium-temperature (mid-T) furnace baking was conducted at 650 MHz superconducting radio-frequency (SRF) cavity for circular electron positron collider (CEPC), which enhanced the cavity unloaded quality factor (Q0) significantly. In the vertical test (2.0 K), Q0 of 650 MHz cavity reached 6.4 × 1010 at 30 MV/m, which is remarkably high at this unexplored frequency. Additionally, the cavity quenched at 31.2 MV/m finally. There was no anti-Q-slope behavior after mid-T furnace baking, which is characteristic of 1.3 GHz cavities. The microwave surface resistance (RS) was also studied, which indicated both very low Bardeen–Cooper–Schrieffer (BCS) and residual resistance. The recipe of cavity process in this paper is simplified and easy to duplicate, which may benefit the SRF community.

Peroxiredoxins (Prxs), a large family of antioxidant enzymes, are abundant in all living organisms. Peroxiredoxin A (PrxA) from Arabidopsis thaliana belongs to the typical 2-Cys Prx family and is localized in the chloroplast. This article reports the crystal structure of a PrxA C119S mutant refined to 2.6 Å resolution. The protein exists as a decamer both in the crystal structure and in solution. The structure is in the reduced state suitable for the approach of peroxide, though conformational changes are needed for the resolving process.

Intercellular adhesion molecule-1(ICAM-1) is a potential molecular target and biomarker for triple negative breast cancer (TNBC) therapy and diagnosis. In this study, aICAM-1 was radioiodinated with 125I/131I in high radiochemical yield and the probes for TNBC tumor targeting and radioimmunotherapy were evaluated in tumor-bearing mice. High and specific accumulation of 125I-aICAM1 in TNBC MDA-MB-231 tumor was observed in SPECT imaging and the tumor grew was inhibited obviously by 131I-aICAM1. Thus, the radioiodinated aICAM1 could serve as potential agents for TNBC theranostics.

Introduction A novel radiotracer 1-(2-(2-(2-[ 18 F ]fluoroethoxy)ethoxy)ethyl)-1H-1,2,3-triazole- estradiol ([ 18 F ]FETE) was successfully synthesized, characterized and evaluated in mice for estrogen receptor (ER)-positive breast cancer targeting with positron emission tomography (PET) imaging. Methods The tosylate precursor 3 was radiolabeled with 18 F and then reacted with 17α-ethinyl-estradiol to produce the final [ 18 F ]FETE. The physicochemical properties of [ 18 F ]FETE were tested in vitro, including determination of the octanol/water partition coefficient, stability and cellular uptake in MCF-7 (ER-positive) and MDA-MB-231 (ER-negative) cells. An ex vivo biodistribution study was performed in normal Sprague Dawley rats, and in vivo microPET imaging was performed on MCF-7 and MDA-MB-231 tumor-bearing mice. The results of biodistribution and PET imaging of [ 18 F ]FETE were compared with that of known 16α-[ 18 F ]fuoro-17β-estradiol ([ 18 F ]FES). Radiation dose estimates for [ 18 F ]FETE were also analyzed. Results [ 18 F ]FETE was obtained in high radiochemical yield (46.59 ± 8.06%) with high radiochemical purity (> 99%) after HPLC purification and high molar activity (15.45 ± 3.15 GBq/μmol). [ 18 F ]FETE is a moderate lipophilic compound with good in vitro stability and the total synthesis time was 55 to 65 min. In biodistribution studies, [ 18 F ]FETE showed high uptake in the ER-abundant uterine tissue of normal immature SD rats (8.55 ± 1.21 and 6.83 ± 1.70%ID/g at 1 h after intravenous and intraperitoneal injection, respectively), and could be blocked with estradiol effectively (the uterus uptake was decreased to 0.63 ± 0.35%ID/g at 1 h after iv injection). MicroPET imaging of tumor-bearing mice with [ 18 F ]FETE at 1 h after iv injection revealed considerable uptake in ER-positive MCF-7 tumors (4.63 ± 0.73%ID/g) that could be inhibited (1.47 ± 0.29%ID/g) and low uptake in ER-negative MDA-MB-231 tumors (1.97 ± 0.36%ID/g). [ 18 F ]FES has relatively low uptake in ER-positive tumor (0.24 ± 0.19%ID/g) when compared with [ 18 F ]FETE. The adult female effective radiation dose of [ 18 F ]FETE in mice was estimated as 0.0022 mSv/MBq. Conclusions A novel 17α-ethinyl-estradiol-based ER probe [ 18 F ]FETE was developed with high molar activity and good in vitro stability. Based on the results of bio-evaluation in normal immature rats and tumor-bearing mice, it might be a promising candidate for specific PET imaging of ER-positive breast cancer.

In order to accommodate the luminosity improvement strategy, two superconducting 499.8 MHz radio frequency (rf) cavities have been adopted for the Upgrade project of Beijing Electron Positron Collider (BEPCII), a double-ring electron–positron collider as well as a synchrotron radiation (SR) light source. The in-house development of the 499.8 MHz superconducting cavity system was initiated at IHEP since 2008. One prototype niobium cavity with all the parts except for the flanges and the pickup port formed by spinning was fabricated and then vertical-tested successfully in July 2011. Four prototype input couplers were manufactured and high-power tested with one reaching a maximum rf power of continuous wave (cw) 420 kW. One prototype HOM damper with a satisfactory absorbing efficiency at the desired frequency band was also constructed and high power tested up to cw 4.4 kW. In the meanwhile, a frequency tuner consisting of a stepping motor and a piezoelectric oscillator was developed. Finally, the bare cavity was dressed with one input coupler, two HOM dampers and one frequency tuner, mounted in a domestic-developed cryostat and then high-power tested successfully in Oct. 2011. The achieved accelerating voltage is 2.2 MV with corresponding Q 0 measured to be 5.8 × 10 8 , beyond the designed goal. This is the first in-house developed 499.8 MHz HOM-damped superconducting cavity system in China. The design, fabrication, post processing and tests of the niobium bare cavity and its auxiliaries, as well as the horizontal high-power test of the cavity system are presented.

Complement factor H (CFH) is a soluble complement regulatory protein essential for the down-regulation of the alternative pathway on interaction with specific markers on the host cell surface. It recognizes the complement component 3b (C3b) and 3d (C3d) fragments in addition to self cell markers (i.e. glycosaminoglycans, sialic acid) to distinguish host cells that deserve protection from pathogens that should be eliminated. The Staphylococcus aureus surface protein serine–aspartate repeat protein E (SdrE) was previously reported to bind human CFH as an immune-evasion tactic. However, the molecular mechanism underlying SdrE–CFH-mediated immune evasion remains unknown. In the present study, we identified a novel region at CFH's C-terminus (CFH1206–1226), which binds SdrE N2 and N3 domains (SdrEN2N3) with high affinity, and determined the crystal structures of apo-SdrEN2N3 and the SdrEN2N3–CFH1206–1226 complex. Comparison of the structure of the CFH–SdrE complex with other CFH structures reveals that CFH's C-terminal tail flips from the main body to insert into the ligand-binding groove of SdrE. In addition, SdrEN2N3 adopts a ‘close’ state in the absence of CFH, which undergoes a large conformational change on CFH binding, suggesting a novel ‘close, dock, lock and latch' (CDLL) mechanism for SdrE to recognize its ligand. Our findings imply that SdrE functions as a ‘clamp' to capture CFH's C-terminal tail via a unique CDLL mechanism and sequesters CFH on the surface of S. aureus for complement evasion. * C3, : complement component 3; C5, : complement component 5; CCP, : complement-control protein; CFH, : complement factor H; Fg, : fibrinogen; GAG, : glycosaminoglycan; ITC, : isothermal titration calorimetry; LB, : Luria–Bertani; MSCRAMM, : microbial surface component recognizing adhesive matrix molecule; OspE, : outer surface protein E; SdrE, : serine–aspartate repeat protein

Folate receptor is an ideal target for tumor-specific diagnostic and therapeutic. The aim of this study was to synthesize 99m Tc-labeled folate-polyamidoamine dendrimer modified with 2-hydrazinonicotinic acid (99m Tc-HP3 FA) for FR imaging. The 99m Tc-HP3 FA conjugate was prepared using N-tris-(hydroxymethyl)-methylglycine and trisodium triphenylphosphine-3,3',3″-trisulfonate as coligands. Physicochemical properties, in vitro cell uptake study, and in vivo micro-single-photon emission computed tomography/CT imaging were performed. The radiolabeled 99m Tc-HP3 FA conjugate was prepared with high radiolabeling yield, good stability, and water solubility (logP = -1.70 ± 0.21). In cell uptake study, the radiolabeled conjugate showed high uptakes in the FR-abundant KB cells and could be blocked significantly by excess folic acid. The 7721 cells which served as control group substantially had no uptakes. The results of micro-single-photon emission computed tomography/CT imaging exhibited that high accumulation of activity was found in FR-overexpressed KB tumor, and the tumor-to-muscle ratio was approximately 25.78, while, using free FA as inhibitor, the uptakes of 99m Tc-HP3 FA in KB tumor and kidney were obviously inhibited. In summary, a new radiocompound was synthesized successfully with specific FR targeting ability. The feasibility of 99m Tc-HP3 FA for early diagnosis of FR-positive tumors with non-invasive single-photon emission computed tomography imaging was demonstrated and the possibility of imaging-guided drug delivery based on multifunctional polyamidoamine will be studied in the future.

In order to intensively complete the automatic operation of logging, feeding, peeling, beating branches, making wood and so on, and satisfy the requirements of forest harvesting, the control system of forest harvesting needs to be studied urgently. The control system designed in this paper uses CAN bus, upper computer (IPC), lower computer (SPN-M*-18 controller), displayer, hand shank and diameter measuring encoder, length measuring encoder, etc. This paper introduces the system composition, hardware composition, software application, displayer design and cutting effect test. The application of CAN bus makes the communication between the host computer and the lower computer as well as other devices smooth, and the anti-interference ability is enhanced. Under the function of the controller, the operation of the equipment is realized, and the labor productivity is improved. The PID controller used in the program ensures the length of the wood in the automatic feeding process, so as to meet the project requirements. The design of the displayer screen makes the operation and maintenance of the operators easier and more convenient. After several experiments, the conclusion is reached that the control system meets the design requirements and can be used in production operations.

650 MHz 2-cell superconducting cavities are proposed for the main ring of the Circular Electron–Positron Collider (CEPC). The cavity is designed with two detachable double-notch higher order mode (HOM) couplers to suppress the fundamental mode and extracted the HOM power. The present paper describes the design, fabrication, surface treatment and vertical tests of the cavities and HOM couplers. The performances of the cavity at 2 K is not affected after the installation of the HOM coupler. The maximum intrinsic quality factor Q 0 of the cavity dressed with the HOM coupler reached 3 . 1 × 1 0 10 at operation accelerating gradient. The vertical tests results showed that the fundamental mode external quality factor Q e of all HOM couplers is an order of magnitude larger than Q 0 of the cavity. The HOM damping results for the 650 MHz 2-cell cavity were also measured at cryogenic temperature and compared with the simulated and measured results at room temperature. Two 650 MHz 2-cell cavities each with two HOM couplers will be assembled in the CEPC 650 MHz test cryomodule after helium vessel dressing.

A dual-vacuum furnace with the heater in the outside vacuum has been developed at the Institute of High Energy Physics (IHEP) to perform nitrogen doping (N-doping) heat treatment of 1.3 GHz 1-cell niobium cavity. The inner chamber is made of stainless steel, where the cavity is inside. This furnace equipped with cryopump can reach less than 1 × 10−4 Pa and 1 × 10−6 Pa at 800 °C and room-temperature, respectively, which is favorable for N-doping. During the doping process, nitrogen is injected by a mass flow controller with feedback of a film gauge to stabilize the doping pressure. The performance of this furnace during the doping process is introduced in details. Two 1.3 GHz 1-cell cavities made of fine grain niobium have received N-doping at this furnace, and the vertical test results are promising. The best intrinsic quality factor ( Q 0 ) of these cavities have exceeded 3 × 1010 at 24 MV/m, which is the target of vertical test for Circular Electron Positron Collider (CEPC). Besides, the phenomenon of anti-Q-slope is also obvious. It seems that the stainless steel is harmless to the cavity performance.

China Spallation Neutron Source (CSNS) has been in operation for about 2 years, and an upgrade is proposed to compensate the space charge effect. A superconducting radio frequency (SRF) linac with double spoke cavities and medium-beta elliptical cavities has been designed to increase the injection energy from 80MeV to 300MeV, and institute of high energy physics (IHEP) has developed a prototype double spoke cavity at β 0 0.5. The cavity shape was optimized to minimize Ep/Eacc while keeping Bp/Eacc reasonably low. Meanwhile, mechanical design was applied to check stress, Lorentz force detuning and microphonic effects, and to minimize pressure sensitivity. A new input power coupling scheme was proposed to avoid electrons hitting directly on ceramic window. After fabrication and post processing of cavity, the cavity was vertical tested for several times, and mechanical polishing was applied to improve the performance. The cavity finally reached Bp of 140mT at Eacc = 16.1MV/m and Q 0 = 1 . 42 × 1 0 10 under vertical test at 2K.

Background Mental health is closely related to the occurrence of hypertension, particularly the prognosis of hypertension patients. The role of psychotherapy in the occurrence, development, prevention, and prognosis of hypertension, remains to be clarified. Methods/design We will conduct a prospective, double-blind, randomized, multiple-centers study. Eighty patients enrolled in this trial will be randomized at 1:1 ratio. The primary endpoint is will be the reduction of the patient psychological scale (PHQ-9) score. Secondary endpoints will be the drop in blood pressure, awareness of physical and mental health and self-efficacy scale. Measurements will be performed at baseline, 5-week (questionnaires only), 10-week (primary endpoint), using the Anxiety Screening Questionnaire (GAD-7) and Depression Scale (PHQ-9). Data analysis will be carried out using the SPSS v.25 software assuming a level of significance of 5%. Results will be analyzed using multilevel, regression analysis and hierarchical linear models. Discussion We hope to provide some insight in the understanding the underlying mechanism of the novel mindfulness in the management of hypertension related psychological stress/disturbance, and will enable us to develop novel approach to manage essential hypertension and its related psychological disorders. CLINICAL TRIAL REGISTRY:: http://www.chictr.org.cn (ChiCTR1900028258).

An accelerator-driven system (ADS), which combines a particle accelerator with a subcritical core, is commonly regarded as a promising device for the transmutation of nuclear waste, as well as a potential scheme for thorium-based energy production. So far the predominant choice of the accelerator for ADS is a superconducting linear accelerator (linac). This article gives a brief overview of ADS based on linacs, including the motivation, principle, challenges and research activities around the world. The status and future plan of the Chinease ADS (C-ADS) project will be highlighted and discussed in depth as an example.

Because of the abnormal vasculature, most growing solid tumors contain regions that experience either acute or chronic hypoxia. However, tumor cells can maintain a high glycolytic rate even when there is enough oxygen supply. Hypoxia-inducible factors (HIFs) play crucial role in the response of tumor cells to this distinct microenvironment by shifting energy production from mitochondria towards glycolysis. In this review, we focus on the metabolism of tumor cell survival in hypoxic microenvironments. Furthermore, we also emphasize the mechanisms by which hypoxia and HIFs regulate tumor metabolism.

Since the 1990s, the research of cluster economy gradually becomes a topic of interest for academic econo- mists and Management experts. In order to obtain the effects of cluster network structure on the behavior of enterprise im- itation, based on neighbor effect, this paper builds dynamic model of a single enterprise income, then explores the propa- gation of corporate behavior under random network model, small world network model, scale-free network model. On the basis of neighbor average profit, this article makes a comparative analysis of the network structure imitation and then ar- rives at the cluster network structure's influence on the enterprise imitation.

The Chinese ADS proton Linac injector I composed of an electron cyclotron resonance ion source, a low-energy beam transport line, a radio frequency quadrupole (RFQ) accelerator, a medium-energy beam transport (MEBT) line, a superconducting section and beam dump with design goal to achieve CW proton beam with beam current 10 mA and energy gain around 10 MeV. In order to maintain the stability of the RF system, to compensate for the beam load effect and to provide the GUI required for the operation of the RF power system, we have established a LLRF control system. This LLRF system for ADS proton Linac injector I in IHEP consists of RF reference system and LLRF controllers for one RFQ cavity, two MEBT bunching cavities and 14 superconductive spoke cavities. We have adopted a new development mTCA.4-based hardware platform, and it has some characteristics such as faster bandwidth, standardized design, easy operation and maintenance and good expansibility. The LLRF system has been improved and optimized and has now been put into operation. It takes into account the pulse and CW beam flow mode, feedforward and feedback control functions. With the help of this system, we achieved stable operation with narrow pulses, long pulses, and CW modes under different beam loads. This article describes the implementation of this system and presents some initial the CW beam acceleration results with the help of this system at the end of 2016.

Folate receptor is an ideal target for tumor-specific diagnostic and therapeutic. The aim of this study was to synthesize

The horizontal test for the BEPC II 500 MHz spare cavity has been completed at IHEP. The maximum voltage of the cavity reached 2.17 MV, while Q(0) was 5.78x10(8). The process and results of the high power horizontal test are presented and discussed in this paper.