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Photocathode plays an important role in generating high brightness and low emittance electron beam and K-Cs-Sb photocathode is preferred in SRF injectors for its high quantum efficiency, long lifetime, and low thermal emittance. To predict the QE change of K-Cs-Sb at cryogenic temperature more correctly, we have modified the QE formula of Spicer’s photoemission model considering the temperature dependence of work function and mean free path of photocathode material, which is obtained by fitting experimental data. The calculated QE drop of about 90.1% at 36.4 K fits well with the measured QE change in DC-SRF photoinjector at Peking University. This improved formula could provide a method to evaluate the QE performance of semiconductor photocathodes at cryogenic temperature.

BackgroundGlucocorticoid usage and alcohol abuse are the most widely accepted risk factors for nontraumatic osteonecrosis of femoral head (ONFH). Despite distinct etiologies between glucocorticoid-associated ONFH (GONFH) and alcohol-associated ONFH (AONFH), little is known about the differences of the microarchitectural and histomorphologic characteristics between these subtypes of ONFH.PurposesTo investigate bone microarchitecture, bone remodeling activity and histomorphology characteristics of different regions in femoral heads between GONFH and AONFH.MethodsFrom September 2015 to October 2020, 85 patients diagnosed with GONFH and AONFH were recruited. Femoral heads were obtained after total hip replacement. Femoral head specimens were obtained from 42 patients (50 hips) with GONFH and 43 patients (50 hips) with AONFH. Micro-CT was utilized to assess the microstructure of 9 regions of interest (ROIs) in the femoral head. Along the supero-inferior orientation, the femoral head was divided into necrotic region, reactive interface, and normal region; along the medio-lateral orientation, the femoral head was divided into medial region, central region and lateral region. Decalcified and undecalcified bone histology was subsequently performed to evaluate histopathological alterations and bone remodeling levels.ResultsIn the necrotic region, most of the microarchitectural parameters did not differ significantly between GONFH and AONFH, whereas both the reactive interface and normal region revealed a less sclerotic microarchitecture but a higher bone remodeling level in GONFH than AONFH. Despite similar necrotic pathological manifestations, subchondral trabecular microfracture in the necrotic region was more severe and vasculature of the reactive interface was more abundant in GONFH.ConclusionsGONFH and AONFH shared similar microarchitecture and histopathological features in the necrotic region, while GONFH exhibited a less sclerotic microarchitecture and a more active bone metabolic status in both the reactive interface and normal region. These differences between GONFH and AONFH in bone microarchitectural and histopathological characteristics might contribute to the development of disease-modifying prevention strategies and treatments for ONFH, taking into etiologies.

Phase-locked pulses are important for coherent control experiments. Here we present theoretical analyses and start-to-end simulation results for the generation of phase-locked pulses using the Hard X-ray Self-Seeding (HXRSS) system at the European XFEL. As proposed in Ref. [1], the method is based on a combination of self-seeding and fresh-slice lasing techniques. However, at variance with Ref. [1], here we exploit different transverse centroid offsets along the electron beam. In this way we may first utilize part of the electron beam to produce SASE radiation, to be filtered as seed and then generate HXRSS pulses from other parts of the beam applying appropriate transverse kicks. The final result consists in coherent radiation pulses with fixed phase difference and tunable time delay within the bunch length. This scheme should be useful for applications such as coherent x-ray pump-probe experiments.

Feather is a good source of nitrogen but the highly rigid structure limits its utilization and leads to environmental pollution and resource wastage. Traditional feather degradation processes such as alkali hydrolysis and steam pressure cooking not only destroy the amino acids but also consume large amounts of energy. Therefore, searching for feather degrading bacteria to transform feather waste to nitrogen fertilizer to improve soil and plant growth is needed. And this also will solve the soil nitrogen deficiency problem in China. In this study, a bacteria that could degrade feather and promote plant growth was isolated from soil sample using dilution plate method. And the isolated bacteria was identified as Bacillus pumilus JYL according to its morphology, biochemical characteristics and 16S rRNA sequence. And the maximum keratinase activity (57.14 U/mL) was obtained under optimal conditions of 0.036% FeSO4, 0.025% MgSO4, 0.073% K2HPO4, 0.5% feather with 2% inoculant at pH 6.5 fermented for 36 h at 35 ℃ after optimization using (response surface methodology) RSM. The effect of hydrolyzate on wheat seed germination and growth was studied. The results showed that germination engergy and germination index with 3% feather hydrolyzate addition group was 94.22% and 87.52%, significantly higher than that of the control group (p

An antioxidant peptide derived from egg white, Asp-His-Thr-Lys-Glu (DHTKE), possesses specific amino acids related to zinc delivery. This study aimed to demonstrate the molecular basis of interactions between the egg white peptide (DHTKE) and zinc ions and investigate the effect of the DHTKE-Zn complex on zinc delivery through the gastrointestinal system. Approximately one DHTKE molecule can bind one zinc ion (n = 1.048 ± 0.085) through its carboxyl, amino, and imidazole nitrogen groups on Asp, His, and Glu. The formed DHTKE-Zn complex presented uniformly distributed globular particles with a particle size of 100-500 nm and underwent dissociation and re-chelation during gastrointestinal digestion. Moreover, the DHTKE peptide mostly remained stable, with a retention rate of 98.32% under gastrointestinal digestion, although one degradation product (DHTK) was identified by nanoscale liquid chromatography-electrospray ionization-tandem mass spectrometry in the gastrointestinal digests; the effectiveness of DHTKE-Zn digests on enhancing absorption of zinc was comparable to that of the initial complex.

Most combinatorial optimization problems can be formulated as mixed integer linear programming (MILP), in which branch-and-bound (B\&B) is a general and widely used method. Recently, learning to branch has become a hot research topic in the intersection of machine learning and combinatorial optimization. In this paper, we propose a novel reinforcement learning-based B\&B algorithm. Similar to offline reinforcement learning, we initially train on the demonstration data to accelerate learning massively. With the improvement of the training effect, the agent starts to interact with the environment with its learned policy gradually. It is critical to improve the performance of the algorithm by determining the mixing ratio between demonstration and self-generated data. Thus, we propose a prioritized storage mechanism to control this ratio automatically. In order to improve the robustness of the training process, a superior network is additionally introduced based on Double DQN, which always serves as a Q-network with competitive performance. We evaluate the performance of the proposed algorithm over three public research benchmarks and compare it against strong baselines, including three classical heuristics and one state-of-the-art imitation learning-based branching algorithm. The results show that the proposed algorithm achieves the best performance among compared algorithms and possesses the potential to improve B\&B algorithm performance continuously.

We find that three factors: Dogecoin network externalities, momentum, and tweet sentiment that capture the time-series expected Dogecoin returns. Dogecoin returns are exposed to Dogecoin network factors. We construct the network factors to capture the user adoption of Dogecoin. Moreover, there is a strong time-series momentum effect, and proxies for investor attention strongly forecast future Dogecoin returns. Lastly, we examine potential underlying mechanisms of the Dogecoin price bubble.

Objective: The optimal interval before receiving SARS-COV-2 vaccination for patients who have received anti-CD 20 monoclonal antibodies remains unclear. Methods: We consideredoriginal studies up to 29 October 2022 and conducted searches in Embase,Medrxiv, PubMed, and SSRN. We excluded search results that did not match ourresearch question’s subject. Human immune response outcomes were analyzed inpatients who had previously received anti-CD20 antibody therapy. We analyzedthe collected results using sensitivity curves andforest plots. Results: Twenty-eight studieswith a total of 1455 subjects receiving anti-CD20 monoclonal antibodies wereincluded in the present analysis. The humoral immune response rates to the timebetween the last anti-CD20 treatment and vaccination for 3-6 months, 6 months,6-9 months, and 9-12 months were 0.23 (95% CI 0.14 to 0.36), 0.36 (95% CI 0.19to 0.58), 0.49 (95% CI 0.35 to 0.64) and 0.64 (95% CI 0.48 to 0.77),respectively. The humoral immune response rates were0.16 (95% CI 0.03 to 0.57) when B cell was 0/ul, and 0.49 (95% CI 0.38 to 0.61)when B cells were more than 5/ul. The humoral immune response ratefor multiple sclerosis was 0.39 (95% CI 0.22 to 0.60) and 0.48 (95% CI 0.29 to0.68) for B-cell non-Hodgkin lymphoma. The area underneath the curve(AUC) was 0.69 with a cut-off value of 5.5 months. Conclusions: The present resultssuggested that the optimal interval for SARS-COV-2 vaccination after the finaldose of anti-CD20 monoclonal antibody was 5.5 months.

A new class of pyrimidine derivatives were identified as potent protein tyrosine kinase (PTK) inhibitors for the treatment of idiopathic pulmonary fibrosis (IPF). Most of these small-molecule inhibitors displayed strong enzymatic activity against BTK and JAK3 kinases at concentrations lower than 10 nM. The representative compound N-(3-((5-chloro-2-(4-((1-morpholino)acetylamino)phenylamino)-4-pyrimidinyl)amino)phenyl)acrylamide (6 a) also exhibited high inhibitory potency toward both BTK and JAK kinase families, as well as ErbB4, at a concentration of 10 nM, achieving rates of inhibition higher than 57 %. Additionally, in vivo biological evaluations showed that 6 a can remarkably decrease the severity of IPF disease. All these investigations suggested that the multi-PTK inhibitor 6 a may serve as a promising agent for the treatment of IPF.

The immersed tunnel in the Hong Kong–Zhuhai–Macao Bridge (HZMB) project has a deep alignment and poor geological conditions; the soft soil layer is up to 30-m thick. To protect the structure of the element joints of the immersed tunnel from differential settlement, we developed a special type of bearing that can be placed between the vertical shear keys of the element joints. These bearings ‘remember’ the maximum capacity that the tunnel structure can undertake so that they can guide the force flow from overloads via the tunnel structure to the foundation in the most appropriate manner to protect the shear-transferring structure while fully utilising it. As of now, all the element joints of the thirty-three elements in the HZMB tunnel are being protected with the bearings installed. This paper elaborates on our concept and experiments, based on which our design and applications were carried out.

Paper# 18978

The article is devoted to terms-metaphors in economic discourse. Metaphorical terms of the language of economics have different spheres of sources, the most productive of which is the everyday sphere. Zoonymous metaphorical terms such as bear, bull, wolf, hare, sheep, which occupy an important place in economic discourse, are especially considered. Статья посвящена терминам-метафорам в экономическом дискурсе. Метафорические термины языка экономики имеют различные сферы источники, самой продуктивной из которых является бытовая сфера. Особо рассматриваются зоонимные термины-метафоры, такие как медведь, бык, волк, заяц, овца, которые занимают важное место в экономическом дискурсе.

In order to improve the accuracy of image segmentation without changing the structure of original semantic segmentation models, an approach to train semantic segmentation models by using generative adversarial network (SS-GAN) is proposed. Using adversarial network to distinguish the source of segmented images, the model can learn the high-order relationship between pixels to enhance the spatial continuity of pixels in the segmented image. There are three aspects related to the work: constructing the generative model of fully convolutional network (FCN) structure by using VGG, and segment image preliminarily; constructing the adversarial model and training it by combining the original images, fake segmented images and real segmented images; modifying the loss function, adding the anti-loss to assist segmentation model training, encouraging generative network to learn the inter-pixel relationship independently. Experiments on PASCAL VOC and Cityscapes datasets show that the proposed method achieves better performance than the existing advanced methods, and improves IoU by 1.56% and 1.93%, respectively.

COVID-19 Pandemic facilitates the development of online courses on a large scale. As a supplementary teaching in a special period, online courses play a gratifying role in enabling students to learn repeatedly and master effectively. However, it cannot be ignored that there are still some problems, and we need to find better solutions. This article takes the “Artificial Intelligence” course as an example, through a set of data analysis, puts forward the improvement plan of the network course, and discusses the “before and after class” teaching mode in blended learning. Through this way we could have a glimpse of the future education, which makes full use of online courses and uses online courses as an icing on the cake for traditional classrooms.

This paper reports the study and demonstration of a new variable temporal shaping method capable of generating linearly polarized picosecond laser pulses with arbitrary predefined shapes, which are highly desired by various applications including low emittance high brightness electron bunch generation in photocathode guns. It is found that both high transmittance and high stability of the shaped pulses can be achieved simultaneously when crystals are set at specific phase delay through the fine control of the crystal temperature. Such variable temporal shaping technique may lead to new opportunities for many potential applications over a wide range of laser wavelengths, pulse repetition rates, time structures and power levels, etc. In addition, a new double-pass variable shaping method is also proposed and could significantly simplify the shaper structure and reduce the cost., Proceedings of the 10th Int. Particle Accelerator Conf., IPAC2019, Melbourne, Australia

An upgraded version of DC-SRF photocathode injector (DC-SRF-II) is under development at Peking University. The goal is to achieve an emittance below 0.5 mm-mrad at the bunch charge of 100 pC and repetition rate of 1 MHz. The engineering design of the DC-SRF-II photoinjector was accomplished in this May and the fabrication is ongoing now. This paper presents some details of the engineering design., Proceedings of the 39th Free Electron Laser Conference, FEL2019, Hamburg, Germany

Nitrogen doping studies with 1.3 GHz superconducting cavities were carried out at Peking University in recent years. We have realized 4×10¹⁰ of high quality factor at 12 MV/m and 2.0 K with large grain single cell cavities by heavy doping. To improve the accelerating gradient of high Q cavities, light doping recipe is adopted. Accelerating gradient is improved to 20 MV/m and the quality factor is larger than 3×10¹⁰ at 16 MV/m and 2.0 K for light doped cavities. The nitrogen treatment, test and analysis are presented in this paper., Proceedings of the 19th International Conference on RF Superconductivity, SRF2019, Dresden, Germany

BISOL(Beijing Isotope-Separation-On-Line Neutron-Rich Beam Facility) is a new generation radioactive ion beam(RIB) facility[1]. It consists a CARR nuclear reactor, a high intensity deuteron accelerator and a post accelera-tor. QWR085 cavity is supposed to be used in SCL2 of post accelerator. This paper mainly talks about the elec-tromagnetic design, mechanical design and vibration damper design of QWR085., Proceedings of the 19th International Conference on RF Superconductivity, SRF2019, Dresden, Germany

Antarctic krill (Euphausia superba) might have specific peptides that chelate iron ions and are iron carriers. In this study, iron-binding peptides were isolated from Antarctic krill using enzymatic (trypsin) hydrolysis and immobilized metal affinity chromatography (IMAC); the binding mode and surface morphology of Antarctic krill peptides (AKP)-iron complexes as well as their iron delivery behavior in the gastrointestinal tract were investigated. Results showed that the AKP bound 79.3% of available iron from the enzymatic hydrolysis for 180 min. The contents of negatively-charged amino acids (Asp and Glu) on the AKP showed a positive correlation (r = 0.80) with iron-binding activities (the data includes Asn and Gln), while positively-charged amino acids showed a negative correlation (r = −0.83). Moreover, His, Ser and Thr on the AKP were also involved in the iron-binding activities. Iron-binding peptides from Antarctic krill hydrolysates, isolated using IMAC-Fe3+ and identified using HPLC-MS/MS, showed a mass of 712–2451 Da, and were enriched in Asp (Asn), Glu (Gln), His, Ser or Thr. The iron ions mainly bound to carboxyl groups of AKP, thus forming nano-scale, spherical particles. The iron nanocarriers formed by AKP showed a significant iron transport activity after simulated gastrointestinal digestion, as compared to FeSO4 (P

Purpose: Study on the effect of modified liankou Shengji powder on treating skin injury rats. Materials and Methods: Divided sixteen male SD rats were randomly into four groups: model group, normal group, modified liankoushengji powder group and Yunnan Baiyao powder group. The other three groups except the normal group were modeled as follows to form a mechanical damage animal model: the left three sides of the back were surgically cut into square full-thickness skin defects, deep into the skin, with a length of about 1 cm on the side. After the mold-building was successful, modified liankoushengji powder and Yunnan Baiyao powder were mixed with the appropriate amount of Vaseline into a paste and then applied to the affected area of rats for drug intervention. All rats in the model group were coated with Vaseline twice a day for 4 days. To observe the body temperature and the growth wounds by glare projection of all rats. Then to calculate the wound healing rate. And to detect Vascular Endothelial Growth Factor (VEGF) by ELISA. Results: In modified liankoushengji powder group, the body temperature was no observable change comparing with the normal group (p> 0.05). But the changes of the increased new capillary formation and the enhanced wound healing rate were significant differences comparing with the normal group(p 0.05). The changes of the increased new capillary formation and the enhanced wound healing rate were significant differences in the modified liankoushengji powder group comparing with the Yunnan Baiyao powder group(p

Extension of gas fuel flexibility of a current production SGT-400 industrial gas turbine combustor system is reported in this paper. A SGT-400 engine with hybrid combustion system configuration to meet a customer's specific requirements was string tested. This engine was tested with the gas turbine package driver unit and the gas compressor-driven unit to operate on and switch between three different fuels with temperature-corrected Wobbe index (TCWI) varying between 45 MJ/m3, 38 MJ/m3, and 30 MJ/m3. The alteration of fuel heating value was achieved by injection or withdrawal of N2 into or from the fuel system. The results show that the engine can maintain stable operation on and switching between these three different fuels with fast changeover rate of the heating value greater than 10% per minute without shutdown or change in load condition. High-pressure rig tests were carried out to demonstrate the capabilities of the combustion system at engine operating conditions across a wide range of ambient conditions. Variations of the fuel heating value, with Wobbe index (WI) of 30 MJ/Sm3, 33 MJ/Sm3, 35 MJ/Sm3, and 45 MJ/Sm3 (natural gas, NG) at standard conditions, were achieved by blending NG with CO2 as diluent. Emissions, combustion dynamics, fuel pressure, and flashback monitoring via measurement of burner metal temperatures, were the main parameters used to evaluate the impact of fuel flexibility on combustor performance. Test results show that NOx emissions decrease as the fuel heating value is reduced. Also note that a decreasing fuel heating value leads to a requirement to increase the fuel supply pressure. Effect of fuel heating value on combustion was investigated, and the reduction in adiabatic flame temperature and laminar flame speed was observed for lower heating value fuels. The successful development program has increased the capability of the SGT-400 standard production dry low emissions (DLE) burner configuration to operate with a range of fuels covering a WI corrected to the normal conditions from 30 MJ/N·m3 to 49 MJ/N·m3. The tests results obtained on the Siemens SGT-400 combustion system provide significant experience for industrial gas turbine burner design for fuel flexibility.

Development of SRF technology has been included in the project of Soft X-ray FEL (SXFEL) for a hard X-ray FEL plan in China which would be operated in CW mode. Six 9-cell TESLA type cavities as well as several single-cell cavities made of Ningxia large grain niobium material have been fabricated by Peking University for achieving high gradient and high intrinsic quality factor Q0. The measurements of gradient and Q0 have been carried out with a new vertical test system at PKU. The process of fabrication, surface treatment and test results of these large grain cavities will be presented., Proceedings of the 18th Int. Conf. on RF Superconductivity, SRF2017, Lanzhou, China

A new vertical test system (VTS) for superconducting RF cavities has been designed and constructed at Peking University. This facility is designed to operate at a temperature of 2K and with pumping speed of 10g/s for helium gas at 30 mbar. In this paper, we present the structure design, modification of 2K system, ambient magnetic field and radiation shielding, LLRF and the test run of this VTS., Proceedings of the 18th Int. Conf. on RF Superconductivity, SRF2017, Lanzhou, China

In this paper, we study a simple harmonic lasing scheme to extend the wavelength of X-ray self-seeding FELs. The self-seeding amplifier is comprised of two stages. In the first stage, the fundamental radiation is amplified but well restricted below saturation, and simultaneously harmonic radiation is generated. In the second stage, the fundamental radiation is suppressed while the harmonic radiation is amplified to saturation. We performed a start-to-end simulation to demonstrate third harmonic lasing in a soft x-ray self-seeding FEL at the fundamental wavelength of 1.52 nm. Our simulations show that a stable narrow-band FEL at GW levels can be obtained., Proceedings of the 38th Int. Free Electron Laser Conf., FEL2017, Santa Fe, NM, USA

A well test analysis model for fractured and vuggy carbonate reservoir of wells drilling in large scale cave considering wellbore storage and skin factor is established in this paper. The Laplace transformation and Stehfest numerical inversion are applied to obtain the results of wellbore pressure. Through the sensitivity analysis of different parameters for the well test typical curves, it is found that the change of the well test curves is in accordance with the theoretical analysis. With the increase of skin factor, the hump of well test typical curves is steeper. The storage ratio influences the depth and width of the concave in the pressure derivative curves. The cross flow coefficient mainly affects the position of the concave occurrence in the pressure derivative curves. The dimensionless reservoir radius mainly affects the middle and late stages of the log-log pressure type curves, and the later well test curves will be upturned for sealed boundary. The duration of the early stage of the log-log curves will become longer when drilling in large scale cave. The effective well radius is increased to a certain extent, which is in full agreement with the conclusions in this paper. The size of the caves has the same effect on the well test typical curves as wellbore storage coefficient. Due to acidification, fracturing, and other reasons, the boundary of the cave will collapse. Therefore, considering the wellbore storage coefficient and skin effect is very important during well testing. However, the existing models for well testing of fractured and vuggy carbonate reservoir often ignore the wellbore storage coefficient and skin effect. For fractured and vuggy carbonate reservoirs of well drilling in large scale cave, the existing models are not applicable. Since the previous models are mostly based on the triple-porosity medium and the equivalent continuum. The well test model for well drilling in large scale cave of fracture-cavity carbonate reservoirs with wellbore storage coefficient and skin factor in this work has significant application value for oil field.

The proposed high repetition-rate electron beam from the LCLS-II and LCLS-II High Energy (LCLS-II-HE) upgrade are promising sources as drivers for an X-ray FEL Oscillator (XFELO) operating at both the harmonic and fundamental frequencies. In this contribution we present start-to-end simulations for an XFELO operating at the fifth harmonic with 4 GeV LCLS-II beam and at the fundamental with 8 GeV LCLS-II-HE beam. The electron beam longitudinal phase space is optimized by shaping the photoinjector laser and adjusting various machine parameters. The XFELO simulations show that high-flux output radiation pulses with 10¹⁰ photons and 3 meV (FWHM) spectral bandwidth can be obtained with the 8 GeV configuration., Proceedings of the 38th Int. Free Electron Laser Conf., FEL2017, Santa Fe, NM, USA

Nitrogen doping studies were carried out at Peking University. A series of 1.3 GHz single cell cavities fabricated with OTIC large grain niobium material were annealed and doped in the furnace of Peking University, and electropolished by a simple EP device. Light doping recipe and heavy doping recipe are both adopted for comparison. The results and analysis are presented in this paper., Proceedings of the 29\textsuperscript{th} Linear Accelerator Conf., LINAC2018, Beijing, China

Self-seeded high-gain harmonic generation is a possible way to extend the wavelength of a soft x-ray free-electron laser (FEL). We have carried out simulation study on harmonic generation within the photon energy range from 2 keV to 4.5 keV, which is difficult to achieve due to a lack of monochromator materials. In this work, we demonstrate the third harmonic FEL with the fundamental wavelength at 1.52 nm. Our results shows that, by using undulator tapering technique, sub-terawatt narrow-bandwidth FEL output can be obtained., Proceedings of the 38th Int. Free Electron Laser Conf., FEL2017, Santa Fe, NM, USA

Experimental study on superconducting electron linac has been developed at Peking University. Stable operation of a DC-SRF photoinjector and a 2*9-cell SRF linac has been realized with an average beam current of mA scale in macro pulses of several ms with a repetition rate of 10 Hz. A compact high repetition rate THz radiation source has been developed based on DC-SRF photo-injector through velocity bunching. Superradiant THz radiation with a repetition rate of 16.25 MHz and a frequency that can be tuned from 0.24 to 0.42 THz was generated by varying the electron beam energy from 2.4 to 3.1 MeV. MeV UED at MHz repetition rate has been demonstrated experimentally using electron pulses from the DC-SRF photoinjector. THz undulator radiation of ~1THz central frequency with an average power of 1W has been achieved with 13MeV electron beam from SRF linac and applications are underway., Proceedings of the 13th Symposium on Accelerator Physics, SAP2017, Jishou, China

Magnesium diboride (MgB2) is a promising candidate material for SRF cavities because of its higher transition temperature and critical field compared with niobium. To meet the demand of RF test devices, the fabrication of large-area MgB2 films on metal substrates is needed. In this work, MgB2 films with 50-mm diameter were fabri-cated on Cu substrates by using an improved HPCVD setups at Peking University. The transition temperatures of MgB2 film on Cu substrate and with Mo buffer layer on Cu substrate are 36.2 K and 36.5 K, respectively. The fabrication processes, surface morphology, superconduct-ing properties of these large-area MgB2 films are present-ed., Proceedings of the 18th Int. Conf. on RF Superconductivity, SRF2017, Lanzhou, China

The performance of superconducting cavities is influenced by the trapped flux during the cooling down through critical temperature, especially for nitrogen doped cavities which are more sensitive to flux trapping. We have investigated the flux trapping of OTIC niobium samples with different grain size. Samples were prepared and heat treated at 800°C and 900°C, followed with different surface removal by BCP. A series of measurements, including MPMS, TOF-SIMS, were carried out on the niobium samples. The results and analysis will be presented., Proceedings of the 18th Int. Conf. on RF Superconductivity, SRF2017, Lanzhou, China

The influence of initial state variables on flood forecasting accuracy by using conceptual hydrological models is analyzed in this paper and a novel flood forecasting method based on correction of initial state variables is proposed. The new method is abbreviated as ISVC (Initial State Variable Correction). The ISVC takes the residual between the measured and forecasted flows during the initial period of the flood event as the objective function, and it uses a particle swarm optimization algorithm to correct the initial state variables, which are then used to drive the flood forecasting model. The historical flood events of 11 watersheds in south China are forecasted and verified, and important issues concerning the ISVC application are then discussed. The study results show that the ISVC is effective and applicable in flood forecasting tasks. It can significantly improve the flood forecasting accuracy in most cases.

La presencia de personajes lésbicos ha aumentado en las narrativas audiovisuales populares, como en las series de televisión o las películas. Por ello es necesario explorar su percepción en audiencias heterogéneas. El objetivo de la investigación es explorar la relación entre la homofobia y la identificación con los personajes, el disfrute y el gusto como procesos de recepción narrativa en ficciones audiovisuales protagonizadas por lesbianas. Para ello, se ha realizado un trabajo empírico compuesto por un cuestionario en línea en el que 140 participantes contestaron primero a preguntas sobre su grado de homofobia, en segundo lugar realizaron un visionado y, finalmente, contestaron preguntas relativas a la identificación, el disfrute y el gusto. Tras obtener las evidencias de validez de la escala de Homofobia Moderna de Lesbianas (mhS-l) se exploraron las relaciones entre las dimensiones de la escala y el resto de variables. Los principales resultados muestran que las personas que tienen un grado menor de homofobia institucional disfrutan en mayor medida y les gusta más el video. Asimismo, se evidenció que los hombres se identifican más intensamente con los personajes de lesbianas, y los gais y lesbianas disfrutan más. Estos resultados se interpretan a la luz de las teorías del entretenimiento mediático. A presença de personagens lésbicas tem aumentado nas narrativas audiovisuais populares, como as séries de televisão ou os filmes. Por isso é necessário explorar sua percepção em audiências heterogêneas. O objetivo da pesquisa é explorar a relação entre a homofobia e a identificação com as personagens, o disfrute e o gosto como processos de recepção narrativa em ficções audiovisuais protagonizadas por lésbicas. Para isto, se tem realizado um trabalho empírico composto por um questionário online no que 140 participantes contestaram primeiro a perguntas sobre seu grau de homofobia, em segundo lugar realizaram um visionado e finalmente, contestaram perguntas relativas à identificação, o disfrute e o gosto. Após obter as evidências de validez da escala de Homofobia Moderna de Lésbicas (mhS-l) exploraram-se as relações entre as dimensões da escala e o resto de variáveis. Os principais resultados mostram que as personagens que têm um grau menor de homofobia institucional disfrutam em maior medida e gostam mais do vídeo. Igualmente, os homens identificam-se mais intensamente com as personagens de lésbicas e os gays e lésbicas desfrutam mais. Estes resultados interpretam-se à luz das teorias do entretenimento mediático. The presence of lesbian characters has increased in popular audiovisual narratives such as television series and movies. It is therefore necessary to explore how they are perceived by heterogeneous audiences. The main goal of this research is to explore the relationship between homophobia, identification with characters, and enjoyment as processes of narrative reception in audiovisual fiction featuring lesbians. To do this, an empirical study was carried out, consisting of an online questionnaire in which 140 participants answered questions about their degree of homophobia. Then they watched prescribed television material and finally answered questions related to identification, enjoyment, and taste. Afer obtaining evidence of the validity of the Modern Homophobia Scale (mhS-l), the relationships between the scale’s dimensions and other variables were explored. The primary results show that people who have a lower degree of institutional homophobia enjoy the video and like it more. Likewise, men identify more intensely with lesbian characters and gays and lesbians enjoy it more. These results are interpreted in the light of media entertainment theories.

Ischemia/reperfusion is a leading cause of liver damage after surgical intervention, trauma, and transplantation. It has been reported that the nicotinamide adenine dinucleotide-dependent deacetylase sirtuin 1 attenuates myocardial, cerebral, and renal ischemia/reperfusion damage. This study aimed to investigate the involvement of sirtuin 1-mediated p66shc inhibition in liver ischemia/reperfusion and explore the effect of carnosic acid and ischemic preconditioning on liver ischemia/reperfusion-induced damage.Laboratory investigation.University laboratory.Male Sprague-Dawley rats and HepG2 cells.The rats were subjected to 45 minutes of ischemia to 70% of the liver, followed by 3-hour reperfusion. The HepG2 cells were subjected to hypoxia/reoxygenation-induced injury.In the rats with liver ischemia/reperfusion injury, carnosic acid pretreatment and ischemic preconditioning dramatically reduced the serum aminotransferase activity and proinflammatory chemokine levels and improved the liver histological evaluations. Carnosic acid and ischemic preconditioning also increased manganese superoxide dismutase and Bcl-xL, but down-regulated cleaved caspase-3. Interestingly, the protective effect of carnosic acid and ischemic preconditioning was positively associated with sirtuin 1 activation. By contrast, p66shc, a kinase that promotes oxidative injury and apoptosis, was inhibited by carnosic acid and ischemic preconditioning. Sirtuin 1 small interfering RNA knockdown experiments confirmed that carnosic acid increased sirtuin 1-mediated repression of p66shc in HepG2 cells and that the protective effect of carnosic acid against hypoxia/reoxygenation injury was inhibited by the sirtuin 1 inhibitor nicotinamide. These results suggest that carnosic acid protects hepatocytes from hypoxia/reoxygenation damage through sirtuin 1-mediated p66shc suppression. To support this notion, we further demonstrated that the sirtuin 1 activator resveratrol achieved a protective effect similar to that of carnosic acid against hypoxia/reoxygenation injury, whereas sirtuin 1 small interfering RNA and nicotinamide had the opposite effect.Carnosic acid and ischemic preconditioning protect against ischemia/reperfusion-induced liver injury. Mechanistically, the protective effect involves the sirtuin 1-mediated inhibition of p66shc, suggesting that this pathway is a novel potential therapeutic target for protecting the liver from ischemia/reperfusion injury.

Dioscin exhibits a range of pharmacological actions but little is known of its effects on cisplatin (CDDP)-induced nephrotoxicity. Here, we have assessed the effects and the possible mechanisms of dioscin against CDDP-induced nephrotoxicity.We used an in vivo model of CDDP-induced nephrotoxicity in rats and mice and, in vitro, cultures of NRK-52E and HK-2 cells. The dual luciferase reporter assay was used to demonstrate modulation, by dioscin, of the targeting of sirtuin 1 (Sirt1) by microRNA (miR)-34a. Molecular docking assays were used to analyse the effects of dioscin with Sirt1, Keap1 and NF-κB.Dioscin attenuated cell damage in vitro and decreased renal injury in rats and mice, treated with CDDP. In terms of mechanisms, dioscin reversed CDDP-induced up-regulation of miR-34a and thus up-regulated Sirt1 levels. In addition, dioscin altered levels of haem oxygenase 1, glutathione-cysteine ligase subunits (GCLC, GCLM) and Keap1, along with increased nuclear translocation of Nrf2, thus decreasing oxidative stress. Also, dioscin affected levels of AP-1, COX-2, HMGB1, IκB-α, IL-1β, IL-6 and TNF-α and decreased the ratio of acetylated NF-κB and normal NF-κB, to suppress inflammation. From molecular docking assays, dioscin directly bound to Sirt1, Keap1 and NF-κBp65 by hydrogen bonding and/or hydrophobic interactions.Our results have linked CDDP-induced nephrotoxicity and the miR-34a/Sirt1 signalling pathway, which was modulated by dioscin. This natural product could be developed as a new candidate to alleviate CDDP-induced renal injury.

This thesis aims at revealing the fundamental guiding and coupling properties of nonreciprocal electromagnetic surface waves on magneto-optical or gyromagnetic media and designing novel applications based on the properties. We introduce the background in the first chapter. We then describe the concept of nonreciprocity and the main calculation method in the second chapter. In the third chapter, we show that one-way waves can be sustained at the edge of a gyromagnetic photonic crystal slab under an external magnetic field. We also investigate the coupling between two parallel one-way waveguides. We reveal the condition for effective co-directional and contra-directional coupling. We also notice that the contra-directional coupling is related to the concept of a “trapped rainbow”. In the fourth chapter, we address the concept of a “trapped rainbow”. It aims at trapping different frequency components of the electromagnetic wave packet at different positions in space permanently. In previous structures, the entire incident wave is reflected due to the strong contra-directional coupling between forward and backward modes. To overcome this difficulty, we show that utilizing nonreciprocal waveguides under a tapered external magnetic field can achieve a truly “trapped rainbow” effect at microwave frequencies. We observe hot spots and relatively long duration times around critical positions through simulations and find that such a trapping effect is robust against disorders. Lastly, in the fifth chapter, we study the one-way waves in a surface magnetoplasmon cavity. We find that the external magnetic field can separate the clockwise and anti-clockwise cavity modes into two totally different frequency ranges. This offers us more choices, both in the frequency ranges and in the one-way directions, for realizing one-way components. We also show the waveguide-cavity coupling by designing a circulator, which establishes the foundation for potential applications. QC 20160816

The 4 GeV LCLS-II superconducting linac with high repetition beam rate enables the possibility to drive an X-Ray FEL oscillator at harmonic frequencies *. Compared to the regular LCLS-II machine setup, the oscillator mode requires a much longer bunch length with a relatively lower current. Also a flat longitudinal phase space distribution is critical to maintain the FEL gain since the X-ray cavity has extremely narrow bandwidth. In this paper, we study the longitudinal phase space optimization including shaping the initial beam from the injector and optimizing the bunch compressor and dechirper parameters. We obtain a bunch with a flat energy chirp over 400 fs in the core part with current above 100 A. The optimization was based on LiTrack and Elegant simulations using LCLS-II beam parameters., Proceedings of the 7th Int. Particle Accelerator Conf., IPAC2016, Busan, Korea

The DC-SRF photoinjector, developed at Peking University, uses Cs2Te as the photocathode and accordingly 266 nm laser is used as the drive laser. A drive laser sys-tem，which includes a 1064 nm laser oscillator, a four-stage amplifier, and second and fourth harmonic genera-tors, has been designed and applied successfully. To avoid the high average current electron beam from hitting the vacuum tube and causing safety problems, a laser pulse selector with an EO modulator has been designed and included into the laser drive system to reduce the repetition rate of electron pulses during the DC-SRF photoinjector commissioning. It can adjust the repetition rate of laser pulses from 81.25 kHz to 81.25 MHz. In this paper, we introduce the drive laser system and describe the laser pulse selector in detail., Proceedings of the 7th Int. Particle Accelerator Conf., IPAC2016, Busan, Korea