If a metalens integrates the circular polarization(CP)conversion function,the focusing lens together with circular-polariz-ing lens(CPL)in traditional cameras may be replaced by a metalens.However,in terahertz(THz)ban...If a metalens integrates the circular polarization(CP)conversion function,the focusing lens together with circular-polariz-ing lens(CPL)in traditional cameras may be replaced by a metalens.However,in terahertz(THz)band,the reported metalenses still do not obtain the perfect and strict single-handed CP,because they were constructed via Pancharatnam-Berry phase so that CP conversion contained both left-handed CP(LCP)and right-handed CP(RCP)components.In this paper,a silicon based THz metalens is constructed using dynamic phase to obtain single-handed CP conversion.Also,we can rotate the whole metalens at a certain angle to control the conversion of multi-polarization states,which can simply manipulate the focusing for incident linear polarization(LP)THz wave in three polarization conversion states,in-cluding LP without conversion,LCP and RCP.Moreover,the polarization conversion behavior is reversible,that is,the THz metalens can convert not only the LP into arbitrary single-handed CP,but also the LCP and RCP into two perpen-dicular LP,respectively.The metalens is expected to be used in advanced THz camera,as a great candidate for tradi-tional CPL and focusing lens group,and also shows potential application in polarization imaging with discriminating LCP and RCP.展开更多
γ -actin (ACTG1) gene is a cytoplasmic nonmuscle actin gene, which encodes a major cytoskeletal protein in the sensory hair cells of the cochlea. Mutations in ACTG1 were found to cause autosomal dominant, progressi...γ -actin (ACTG1) gene is a cytoplasmic nonmuscle actin gene, which encodes a major cytoskeletal protein in the sensory hair cells of the cochlea. Mutations in ACTG1 were found to cause autosomal dominant, progressive, sensorineural hearing loss linked to the DFNA 20/26 locus on chromosome 17q25.3 in European and American families, respectively. In this study, a novel missense mutation (c.364A〉G; p.I122V) co-segregated with the affected individuals in the family and did not exist in the unaffected family members and 150 unrelated normal controls. The alteration of residue Ile122 was predicted to damage its interaction with actin-binding proteins, which may cause disruption of hair cell organization and function. These findings strongly suggested that the I122V mutation in ACTG1 caused autosomal dominant non-syndromic hearing impairment in a Chinese family and expanded the spectrum of ACTG1 mutations causing hearing loss.展开更多
Objective To investigate the efficacy, safety, and associated mechanisms of injected ozonated saline in the treatment of VX2 tumors. Methods A total of 90 rabbits bearing VX2 tumors on their left hind legs were random...Objective To investigate the efficacy, safety, and associated mechanisms of injected ozonated saline in the treatment of VX2 tumors. Methods A total of 90 rabbits bearing VX2 tumors on their left hind legs were randomly divided into three groups. The control group(A) received normal saline, while groups B and C received 20 μg/mL and 40 μg/mL O_3/O_2 ozonated saline, respectively. Rabbits were anesthetized and 2 mL of blood was drawn directly from the heart to measure serum concentrations of interleukin(IL-6) and tumor necrosis factor(TNF-α). The skin covering the VX2 tumor was cut in each rabbit and the maximum and vertical diameters of the tumors were measured under direct visualization. Several milliliters of saline, saline pre-treated with 20 μg/mL O_3/O_2, or saline pre-treated with 40 μg/mL O_3/O_2 were directly injected into the tumors of groups A, B, and C, respectively(injection volume(milliliter) =1/2 volume of the tumor, V = 1/2ab^2). On days 4, 8 and 12 following treatment, 10 rabbits were randomly selected from each group for blood sample collection, and serum IL-6 and TNF-α were measured. The tumor growth rate was calculated by measuring the maximum and vertical diameters of the VX2 tumors under direct visualization. All selected rabbits were euthanized and the tumors, livers, and lungs were removed for pathological examination. The tumor necrosis rate was calculated by cutting the tumors into half along the longitudinal axis and measuring the maximum diameters of the intratumoral necrotic regions. Results The average tumor volume in the three groups increased to different degrees at each time point; however, the average tumor growth rates in groups B and C were substantially lower than that in group A, exhibiting a statistically significant difference. The difference in the tumor growth rate between group B and group C was not statistically significant. The serum concentrations of IL-6 and TNF-α increased in the three groups at each time point, with larger increases occurring in groups B and C; however, the greater increases did not reach statistical significance. Although the diameters of the necrotic areas were larger in both groups B and C than that in group A, significant differences in necrotic area diameters were only found when comparing groups A and C on days 4 and 12 following treatment. Conclusion Direct injection of different concentrations of ozonated saline into VX2 tumors significantly increased intratumoral necrosis and reduced the tumor growth rate. The associated mechanism may be partially mediated by IL-6 and TNF-α, as the serum concentrations of these molecules increased after the treatment.展开更多
Freeze-thaw damage is the most common disease of semi-rigid bases in cold regions, which may greatly affect the dura- bility of roadways. In this study, the compressive strength and frost resistance of four different ...Freeze-thaw damage is the most common disease of semi-rigid bases in cold regions, which may greatly affect the dura- bility of roadways. In this study, the compressive strength and frost resistance of four different types of semi-rigid bases (lime-fly ash-stabilized sand, cement-stabilized sand, lime-fly ash-stabilized gravel, and cement-stabilized gravel) are assessed by varying the materials content. Based on freeze-thaw and compressive strength tests, this paper presents the performance of the different materials, each having different physical properties, and the optimal amounts of materials contents are proposed.展开更多
Metasurfaces that can realize the polarization manipulation of electromagnetic waves on the sub-wavelength scale have become an emerging research field.Here,a novel strategy of combining the metasurface and Fresnel zo...Metasurfaces that can realize the polarization manipulation of electromagnetic waves on the sub-wavelength scale have become an emerging research field.Here,a novel strategy of combining the metasurface and Fresnel zone plate to form a metasurface zone plate is proposed to realize the conversion from nearly arbitrary polarizations to a fixed polarization.Specifically,when one polarized wave is incident on adjacent ring zones constructed by different types of meta-atoms,the transmitted waves generated by odd-numbered and even-numbered ring zones converge at the same focus and superimpose to generate a fixed polarized wave.As function demonstrations,we have designed two types of metasurface zone plates:one is a focused linear polarizer,and the other can convert nearly arbitrary polarized waves into focused circularly polarized waves.The simulated and measured results are consistent with theoretical expectations,suggesting that the proposed concept is flexible and feasible.Our work provides an alternative platform for polarization manipulation and may vigorously promote the development of polarization photonic devices.展开更多
The deformation and strength characteristics of roadbed slope under seismic loading in permafrost regions are simulated numerically. The seismic response of roadbed at different positions and inclinations of a slope s...The deformation and strength characteristics of roadbed slope under seismic loading in permafrost regions are simulated numerically. The seismic response of roadbed at different positions and inclinations of a slope section was analyzed. Results show that, roadbed slope damage is mainly led by lateral displacement, and the deformation gradually decreases with increasing depth; roadbed and foundation displacement and plastic strain increases with the magnitude of slope angle, hence the roadbed safety factor will be reduced.展开更多
Donation after circulatory-determined death(DCD)is an important part of renal transplantation.Therefore,DCD renal transplantation animal model should be established to study the mechanism of organ injury.Here,we estab...Donation after circulatory-determined death(DCD)is an important part of renal transplantation.Therefore,DCD renal transplantation animal model should be established to study the mechanism of organ injury.Here,we established a stable DCD rat renal transplantation model and investigated the dynamic regulation of graft self-repairing and antioxidant capacities with different non-heart-beating times(NHBTs).Male Sprague-Dawley rats were randomly divided into four groups with the NHBT of the donors from 0 to 15,30,and 45 minutes.Recipients in long NHBT groups had a significantly lower survival rate and poorer graft function than those in short NHBT groups.Grafts from the 15-minute and 30-minute NHBT groups showed light and severe injury respectively at an early stage after transplantation and recovered within 7 days after transplantation,whereas the self-repairing of the grafts in the 45-minute NHBT group was delayed.The expressions of proliferating cell nuclear antigen(PCNA)and von Willebrand factor(vWF)were dependent on NHBT.The expression of antioxidant proteins paralleled graft recovery.In conclusion,the recipients can up-regulate antioxidant capacity to enhance graft self-repairing in DCD renal transplantation.Prolonged NHBT can delay the self-repairing and antioxidation of grafts.展开更多
The stress produced by repeated train loads decreases with increasing railway subgrade bed depth, and slightly weathered coarse particles of subgrade bed fillings can be broken at different levels under continuous loa...The stress produced by repeated train loads decreases with increasing railway subgrade bed depth, and slightly weathered coarse particles of subgrade bed fillings can be broken at different levels under continuous load. Thus, the mass of fine soil, with a diameter of not more than 0.075 mm, is different at different depths. Fine soil is also sensitive to frost heave and thaw settlement. In order to study the effects of non-uniformly distributed fine soil on the mechanical properties of coarse-grained soil of the Shenyang-Dandong Railway, triaxial tests were conducted with three types of specimens, un- dergoing six freeze-thaw cycle numbers (0, 1, 3, 7, 9, 12) and three confining pressures (100, 200, 300 kPa). The freezing temperature is -5 ~C and the thawing temperature is +15 ~C. The stress-strain behavior, static strength, resilient modulus, cohesive force and the angle of internal friction were measured for different tested specimens. As a result, the law of static strength and resilient modulus of different specimens following the increase of freeze-thaw cycles under three confining pressures is obtained. The changing law of cohesive force and friction angle of three specimens following the increase of freeze-thaw cycles is also calculated, and the different results of different specimens are also compared.展开更多
Polarization is crucial in various fields such as imaging,sensing,and substance detection.A compact,fast,and accurate polarization detection device is vital for these applications.Herein,we demonstrate a multifocus me...Polarization is crucial in various fields such as imaging,sensing,and substance detection.A compact,fast,and accurate polarization detection device is vital for these applications.Herein,we demonstrate a multifocus metalens for terahertz polarization detection that requires only a single measurement to obtain complete polarization parameters and reconstruct the polarization state of the incident field.The individual subarrays of this metalens convert each of the six polarized components into the same polarization,which in turn links the Stokes parameters to these six foci.The incident linear polarizations and elliptical polarizations are characterized by Stokes parameters and polarization ellipses.Simulations and experimental results show that the scheme can accurately detect the incident polarization with a single measurement.The proposed metasurface polarimetry may find applications in the fields of real-time terahertz detection and integrated optics.展开更多
Approximately 94 to 220 million people worldwide are at risk of drinking well water containing arsenic > 10 μg/L, the WHO guideline value. To identify non-compliant domestic wells, assess health risks and reduce e...Approximately 94 to 220 million people worldwide are at risk of drinking well water containing arsenic > 10 μg/L, the WHO guideline value. To identify non-compliant domestic wells, assess health risks and reduce exposure, accurate and rapid on-site inorganic arsenic screening methods are desirable because all domestic wells worldwide need to be tested.Here, the principles, advantages and limitations of commonly used colorimetry, electrochemistry, and biosensing methods are critically reviewed, with the performance compared with laboratory-based benchmark methods. Most commercial kits are based on the classic Gutzeit reaction. Despite being semi-quantitative, the more recent and more expensive products display improved and acceptable accuracy and shorter testing time (~10 min). Carried out by trained professionals, electrochemical methods are also feasible for on-site analysis, although miniaturization is desirable yet challenging. Biosensing using whole bacterial cells or bio-engineered materials such as aptamers is promising, if incorporated with function specific nanomaterials and biomaterials. Since arsenic is frequently found as arsenite in reducing groundwater and subject to oxidation during sampling, transportation and storage, on-site separation and sample preservation are feasible but the specific methods should be chosen based on sample matrix and tested before use. To eliminate arsenic exposure among hundreds of millions of mostly rural residents worldwide, we call for concerted efforts in research community and regulatory authority to develop accurate, rapid, and affordable tests for on-site screening and monitoring of arsenic in drinking water. Access to affordable testing will benefit people who are socioeconomically disadvantaged.展开更多
Only a few fused benzothiadizole(BTz)based conjugated polymers have been applied in organic field-effect transistors(OFETs),and their performances were low,mainly due to the lack of available building blocks and in-de...Only a few fused benzothiadizole(BTz)based conjugated polymers have been applied in organic field-effect transistors(OFETs),and their performances were low,mainly due to the lack of available building blocks and in-depth study of the relationship between structure and performance.Herein,we report two isomeric fused BTz-based building blocks(M1 and M2)and their copolymers PBTzVBTz-T and PBTzVBTz-TT,PTVT-T and PTVT-TT.DFT study showed all polymers had nearly planar backbone geometries,and PBTzVBTz-TT exhibited the most linear backbone.PTVT-T and PTVT-TT exhibited red-shift absorption spectra and deeper LUMO level than those of PBTzVBTz-T and PBTzVBTz-TT.Thin film microstructure study demonstrated PBTzVBTz-TT and PTVT-TT had edge-on molecular orientation,while the others had the mixed molecular orientation of edge-on and face-on.Furthermore,PBTzVBTz-TT had the longest coherence length in thin film.All these features of PBTzVBTz-TT resulted in its highest carrier mobility of 0.1 cm^(2)·V^(–1)·s^(–1) among these polymers.展开更多
Vortex and vector terahertz(THz)beams with inhomogeneous polarization states have become a considerable hot topic in the last decade due to their important roles in multiplexed wireless data transmission.However,the t...Vortex and vector terahertz(THz)beams with inhomogeneous polarization states have become a considerable hot topic in the last decade due to their important roles in multiplexed wireless data transmission.However,the technical instruments to form and evaluate such beams are rather limited,as they are mainly collected in the visible range.The emergence of coded metasurfaces has reinvigorated the design of functional devices with multiple degrees of freedom.Here,we demonstrate a versatile design inspired by a binary encoding approach for generating off-axis vectorial THz beams on all-silicon metasurfaces.Experimentally,simultaneous manipulation of the encoding method within the orthogonal circularly polarized(CP)channel provides strong support for developing versatility in vector THz beams,including the generation of arbitrary polarization profiles and the directional emission of multiplexed vector vortex beams(VVBs)with specified polarization states.The introduction of the latitudinal polarization control factor guarantees that continuously rotating or independently designed vector polarization profiles can be obtained on a pre-defined focal plane.Subsequently,a universal parametric theoretical model is developed to analyze the evolutionary trend of off-axis VVB in detail.Notably,the proposed monolayer vector metasurface bypasses the requirement of multiple cascaded optical elements,further inducing the advancement of ultra-thin vector THz sources,and also facilitating the generation of vector fields with tailored polarization distributions in 3D space.展开更多
The manipulation and detection of polarization states play a crucial role in the application of 6G terahertz communication.Nonetheless,the development of compact and versatile polarization detection devices capable of...The manipulation and detection of polarization states play a crucial role in the application of 6G terahertz communication.Nonetheless,the development of compact and versatile polarization detection devices capable of detecting arbitrary polarizations continues to be a challenging endeavor.Here,we demonstrate a terahertz polarization detection scheme by performing mode purity analysis and multidimensional analysis of the transmitted vortex field.The power of the proposed polarization recognition is verified by using three polarization trajectories,including linear polarizations,circular polarizations,and elliptical polarizations.Using the reconstructed complete polarization parameters,the detected polarization states are characterized using polarization ellipses,Poincarésphere,and full-Stokes parameters.The experimental results validate the power of this scheme in polarization detection.This scheme holds promise for applications in polarization imaging and terahertz communication.展开更多
Premature ovarian failure(POF) is a refractory disease for clinical treatment with the goal of restoring fertility. In this study,umbilical cord mesenchymal stem cells on a collagen scaffold(collagen/UC-MSCs) can acti...Premature ovarian failure(POF) is a refractory disease for clinical treatment with the goal of restoring fertility. In this study,umbilical cord mesenchymal stem cells on a collagen scaffold(collagen/UC-MSCs) can activate primordial follicles in vitro via phosphorylation of FOXO3 a and FOXO1. Transplantation of collagen/UC-MSCs to the ovaries of POF patients rescued overall ovarian function, evidenced by elevated estradiol concentrations, improved follicular development, and increased number of antral follicles. Successful clinical pregnancy was achieved in women with POF after transplantation of collagen/UC-MSCs or UC-MSCs. In summary, collagen/UC-MSC transplantation may provide an effective treatment for POF.展开更多
Intrauterine adhesion(IUA) is a common cause of uterine infertility and one of the most severe clinical features is endometrial fibrosis namely endometrial scarring for which there are few cures currently. Blocked ang...Intrauterine adhesion(IUA) is a common cause of uterine infertility and one of the most severe clinical features is endometrial fibrosis namely endometrial scarring for which there are few cures currently. Blocked angiogenesis is the main pathological change in the scarred endometrium. The fibroblast growth factor 2(b FGF), a member of FGF family, is usually applied to promote healing of refractory ulcer and contributes to angiogenesis of tissues. In this study, the sustained-release system of b FGF100 μg was administrated around scarred endometrium guiding by ultrasound every 4 weeks in 18 patients(2–4 times). Results showed that after treatment, the menstrual blood volume, endometrial thickness and the scarred endometrial area were improved.Histological study showed blood vessel density increased obviously. Three patients(3/18) achieved pregnancy over 20 gestational weeks. Therefore, administrating the b FGF surrounding scarred endometrium may provide a new therapeutic approach for the patients with endometrial fibrosis.展开更多
基金supported by the National Natural Science Foundation of China(Nos.61675147,61735010 and 91838301)National Key Research and Development Program of China(No.2017YFA0700202)Basic Re-search Program of Shenzhen(JCYJ20170412154447469).
文摘If a metalens integrates the circular polarization(CP)conversion function,the focusing lens together with circular-polariz-ing lens(CPL)in traditional cameras may be replaced by a metalens.However,in terahertz(THz)band,the reported metalenses still do not obtain the perfect and strict single-handed CP,because they were constructed via Pancharatnam-Berry phase so that CP conversion contained both left-handed CP(LCP)and right-handed CP(RCP)components.In this paper,a silicon based THz metalens is constructed using dynamic phase to obtain single-handed CP conversion.Also,we can rotate the whole metalens at a certain angle to control the conversion of multi-polarization states,which can simply manipulate the focusing for incident linear polarization(LP)THz wave in three polarization conversion states,in-cluding LP without conversion,LCP and RCP.Moreover,the polarization conversion behavior is reversible,that is,the THz metalens can convert not only the LP into arbitrary single-handed CP,but also the LCP and RCP into two perpen-dicular LP,respectively.The metalens is expected to be used in advanced THz camera,as a great candidate for tradi-tional CPL and focusing lens group,and also shows potential application in polarization imaging with discriminating LCP and RCP.
基金the National Natural Science Foundation of China (No. 30670736 and 30500168)the Department of Science and Technology of Jiangsu Province (No. BS2006533).
文摘γ -actin (ACTG1) gene is a cytoplasmic nonmuscle actin gene, which encodes a major cytoskeletal protein in the sensory hair cells of the cochlea. Mutations in ACTG1 were found to cause autosomal dominant, progressive, sensorineural hearing loss linked to the DFNA 20/26 locus on chromosome 17q25.3 in European and American families, respectively. In this study, a novel missense mutation (c.364A〉G; p.I122V) co-segregated with the affected individuals in the family and did not exist in the unaffected family members and 150 unrelated normal controls. The alteration of residue Ile122 was predicted to damage its interaction with actin-binding proteins, which may cause disruption of hair cell organization and function. These findings strongly suggested that the I122V mutation in ACTG1 caused autosomal dominant non-syndromic hearing impairment in a Chinese family and expanded the spectrum of ACTG1 mutations causing hearing loss.
基金supported by the National Natural Science Foundation of China(81071245)
文摘Objective To investigate the efficacy, safety, and associated mechanisms of injected ozonated saline in the treatment of VX2 tumors. Methods A total of 90 rabbits bearing VX2 tumors on their left hind legs were randomly divided into three groups. The control group(A) received normal saline, while groups B and C received 20 μg/mL and 40 μg/mL O_3/O_2 ozonated saline, respectively. Rabbits were anesthetized and 2 mL of blood was drawn directly from the heart to measure serum concentrations of interleukin(IL-6) and tumor necrosis factor(TNF-α). The skin covering the VX2 tumor was cut in each rabbit and the maximum and vertical diameters of the tumors were measured under direct visualization. Several milliliters of saline, saline pre-treated with 20 μg/mL O_3/O_2, or saline pre-treated with 40 μg/mL O_3/O_2 were directly injected into the tumors of groups A, B, and C, respectively(injection volume(milliliter) =1/2 volume of the tumor, V = 1/2ab^2). On days 4, 8 and 12 following treatment, 10 rabbits were randomly selected from each group for blood sample collection, and serum IL-6 and TNF-α were measured. The tumor growth rate was calculated by measuring the maximum and vertical diameters of the VX2 tumors under direct visualization. All selected rabbits were euthanized and the tumors, livers, and lungs were removed for pathological examination. The tumor necrosis rate was calculated by cutting the tumors into half along the longitudinal axis and measuring the maximum diameters of the intratumoral necrotic regions. Results The average tumor volume in the three groups increased to different degrees at each time point; however, the average tumor growth rates in groups B and C were substantially lower than that in group A, exhibiting a statistically significant difference. The difference in the tumor growth rate between group B and group C was not statistically significant. The serum concentrations of IL-6 and TNF-α increased in the three groups at each time point, with larger increases occurring in groups B and C; however, the greater increases did not reach statistical significance. Although the diameters of the necrotic areas were larger in both groups B and C than that in group A, significant differences in necrotic area diameters were only found when comparing groups A and C on days 4 and 12 following treatment. Conclusion Direct injection of different concentrations of ozonated saline into VX2 tumors significantly increased intratumoral necrosis and reduced the tumor growth rate. The associated mechanism may be partially mediated by IL-6 and TNF-α, as the serum concentrations of these molecules increased after the treatment.
基金supported by the National Natural Science Foundation of China (Nos. 51378057 and 41371081)
文摘Freeze-thaw damage is the most common disease of semi-rigid bases in cold regions, which may greatly affect the dura- bility of roadways. In this study, the compressive strength and frost resistance of four different types of semi-rigid bases (lime-fly ash-stabilized sand, cement-stabilized sand, lime-fly ash-stabilized gravel, and cement-stabilized gravel) are assessed by varying the materials content. Based on freeze-thaw and compressive strength tests, this paper presents the performance of the different materials, each having different physical properties, and the optimal amounts of materials contents are proposed.
文摘Metasurfaces that can realize the polarization manipulation of electromagnetic waves on the sub-wavelength scale have become an emerging research field.Here,a novel strategy of combining the metasurface and Fresnel zone plate to form a metasurface zone plate is proposed to realize the conversion from nearly arbitrary polarizations to a fixed polarization.Specifically,when one polarized wave is incident on adjacent ring zones constructed by different types of meta-atoms,the transmitted waves generated by odd-numbered and even-numbered ring zones converge at the same focus and superimpose to generate a fixed polarized wave.As function demonstrations,we have designed two types of metasurface zone plates:one is a focused linear polarizer,and the other can convert nearly arbitrary polarized waves into focused circularly polarized waves.The simulated and measured results are consistent with theoretical expectations,suggesting that the proposed concept is flexible and feasible.Our work provides an alternative platform for polarization manipulation and may vigorously promote the development of polarization photonic devices.
基金National 973 Project of China (No.2012CB026104)National Natural Science Foundation of China (No.41171064)
文摘The deformation and strength characteristics of roadbed slope under seismic loading in permafrost regions are simulated numerically. The seismic response of roadbed at different positions and inclinations of a slope section was analyzed. Results show that, roadbed slope damage is mainly led by lateral displacement, and the deformation gradually decreases with increasing depth; roadbed and foundation displacement and plastic strain increases with the magnitude of slope angle, hence the roadbed safety factor will be reduced.
基金supported by funds from the National Natural Science Foundation of China(Grant No.81570613 and No.81370853)Jiangsu Provincial Social Development Project(Grant No.BE2017615)2016 Jiangsu Provincial Medical Innovation Team(Grant No.0536).
文摘Donation after circulatory-determined death(DCD)is an important part of renal transplantation.Therefore,DCD renal transplantation animal model should be established to study the mechanism of organ injury.Here,we established a stable DCD rat renal transplantation model and investigated the dynamic regulation of graft self-repairing and antioxidant capacities with different non-heart-beating times(NHBTs).Male Sprague-Dawley rats were randomly divided into four groups with the NHBT of the donors from 0 to 15,30,and 45 minutes.Recipients in long NHBT groups had a significantly lower survival rate and poorer graft function than those in short NHBT groups.Grafts from the 15-minute and 30-minute NHBT groups showed light and severe injury respectively at an early stage after transplantation and recovered within 7 days after transplantation,whereas the self-repairing of the grafts in the 45-minute NHBT group was delayed.The expressions of proliferating cell nuclear antigen(PCNA)and von Willebrand factor(vWF)were dependent on NHBT.The expression of antioxidant proteins paralleled graft recovery.In conclusion,the recipients can up-regulate antioxidant capacity to enhance graft self-repairing in DCD renal transplantation.Prolonged NHBT can delay the self-repairing and antioxidation of grafts.
基金supported by the National Basic Research Program of China(973 program,Grant No.2012CB026104)the National Natural Science Foundation of China(Grant Nos.41271072,41371081 and 51378057)
文摘The stress produced by repeated train loads decreases with increasing railway subgrade bed depth, and slightly weathered coarse particles of subgrade bed fillings can be broken at different levels under continuous load. Thus, the mass of fine soil, with a diameter of not more than 0.075 mm, is different at different depths. Fine soil is also sensitive to frost heave and thaw settlement. In order to study the effects of non-uniformly distributed fine soil on the mechanical properties of coarse-grained soil of the Shenyang-Dandong Railway, triaxial tests were conducted with three types of specimens, un- dergoing six freeze-thaw cycle numbers (0, 1, 3, 7, 9, 12) and three confining pressures (100, 200, 300 kPa). The freezing temperature is -5 ~C and the thawing temperature is +15 ~C. The stress-strain behavior, static strength, resilient modulus, cohesive force and the angle of internal friction were measured for different tested specimens. As a result, the law of static strength and resilient modulus of different specimens following the increase of freeze-thaw cycles under three confining pressures is obtained. The changing law of cohesive force and friction angle of three specimens following the increase of freeze-thaw cycles is also calculated, and the different results of different specimens are also compared.
基金China Postdoctoral Science Foundation(2023TQ0296)Excellent Youth Foundation of Henan Scientific Committee(232300421076)National Natural Science Foundation of China(12174350)。
文摘Polarization is crucial in various fields such as imaging,sensing,and substance detection.A compact,fast,and accurate polarization detection device is vital for these applications.Herein,we demonstrate a multifocus metalens for terahertz polarization detection that requires only a single measurement to obtain complete polarization parameters and reconstruct the polarization state of the incident field.The individual subarrays of this metalens convert each of the six polarized components into the same polarization,which in turn links the Stokes parameters to these six foci.The incident linear polarizations and elliptical polarizations are characterized by Stokes parameters and polarization ellipses.Simulations and experimental results show that the scheme can accurately detect the incident polarization with a single measurement.The proposed metasurface polarimetry may find applications in the fields of real-time terahertz detection and integrated optics.
基金Support was provided by NSFC grants 41831279 and 41772265 to Yan Zhenggrant 2021YFA0715900 from the National Key Research and Development Program of China。
文摘Approximately 94 to 220 million people worldwide are at risk of drinking well water containing arsenic > 10 μg/L, the WHO guideline value. To identify non-compliant domestic wells, assess health risks and reduce exposure, accurate and rapid on-site inorganic arsenic screening methods are desirable because all domestic wells worldwide need to be tested.Here, the principles, advantages and limitations of commonly used colorimetry, electrochemistry, and biosensing methods are critically reviewed, with the performance compared with laboratory-based benchmark methods. Most commercial kits are based on the classic Gutzeit reaction. Despite being semi-quantitative, the more recent and more expensive products display improved and acceptable accuracy and shorter testing time (~10 min). Carried out by trained professionals, electrochemical methods are also feasible for on-site analysis, although miniaturization is desirable yet challenging. Biosensing using whole bacterial cells or bio-engineered materials such as aptamers is promising, if incorporated with function specific nanomaterials and biomaterials. Since arsenic is frequently found as arsenite in reducing groundwater and subject to oxidation during sampling, transportation and storage, on-site separation and sample preservation are feasible but the specific methods should be chosen based on sample matrix and tested before use. To eliminate arsenic exposure among hundreds of millions of mostly rural residents worldwide, we call for concerted efforts in research community and regulatory authority to develop accurate, rapid, and affordable tests for on-site screening and monitoring of arsenic in drinking water. Access to affordable testing will benefit people who are socioeconomically disadvantaged.
基金supported by the National Key Research and Development Program of China(2021YFB2800703 and 2017YFA0700202)the National Natural Science Foundation of China(61675147)Sichuan Science and Technology Program(2021ZYD0039)。
基金supported by National Natural Science Foundation of China(NSFC 32071530 to H.L.)Vegegraphy of China(2015FY210200-13 to S.P.)and Zhang Hongda Science Foundation and Fu Jia-Rui Scholarship of Sun Yat-sen University。
基金The authors are grateful to the National Key Research and Development Program(2018YFA0703200)the National Nat-ural Science Foundation of China(No.21975176).
文摘Only a few fused benzothiadizole(BTz)based conjugated polymers have been applied in organic field-effect transistors(OFETs),and their performances were low,mainly due to the lack of available building blocks and in-depth study of the relationship between structure and performance.Herein,we report two isomeric fused BTz-based building blocks(M1 and M2)and their copolymers PBTzVBTz-T and PBTzVBTz-TT,PTVT-T and PTVT-TT.DFT study showed all polymers had nearly planar backbone geometries,and PBTzVBTz-TT exhibited the most linear backbone.PTVT-T and PTVT-TT exhibited red-shift absorption spectra and deeper LUMO level than those of PBTzVBTz-T and PBTzVBTz-TT.Thin film microstructure study demonstrated PBTzVBTz-TT and PTVT-TT had edge-on molecular orientation,while the others had the mixed molecular orientation of edge-on and face-on.Furthermore,PBTzVBTz-TT had the longest coherence length in thin film.All these features of PBTzVBTz-TT resulted in its highest carrier mobility of 0.1 cm^(2)·V^(–1)·s^(–1) among these polymers.
基金supported by the National Key Research and Development Program of China(Grant Nos.2021YFB2800703,and 2017YFA0700202)the National Natural Science Foundation of China(Grant Nos.61675147,61975146,62075159,62105240,and 91838301).
文摘Vortex and vector terahertz(THz)beams with inhomogeneous polarization states have become a considerable hot topic in the last decade due to their important roles in multiplexed wireless data transmission.However,the technical instruments to form and evaluate such beams are rather limited,as they are mainly collected in the visible range.The emergence of coded metasurfaces has reinvigorated the design of functional devices with multiple degrees of freedom.Here,we demonstrate a versatile design inspired by a binary encoding approach for generating off-axis vectorial THz beams on all-silicon metasurfaces.Experimentally,simultaneous manipulation of the encoding method within the orthogonal circularly polarized(CP)channel provides strong support for developing versatility in vector THz beams,including the generation of arbitrary polarization profiles and the directional emission of multiplexed vector vortex beams(VVBs)with specified polarization states.The introduction of the latitudinal polarization control factor guarantees that continuously rotating or independently designed vector polarization profiles can be obtained on a pre-defined focal plane.Subsequently,a universal parametric theoretical model is developed to analyze the evolutionary trend of off-axis VVB in detail.Notably,the proposed monolayer vector metasurface bypasses the requirement of multiple cascaded optical elements,further inducing the advancement of ultra-thin vector THz sources,and also facilitating the generation of vector fields with tailored polarization distributions in 3D space.
基金China Postdoctoral Science Foundation(2023TQ0296)Excellent Youth Foundation of Henan Scientific Committee(232300421076)National Natural Science Foundation of China(12174350)。
文摘The manipulation and detection of polarization states play a crucial role in the application of 6G terahertz communication.Nonetheless,the development of compact and versatile polarization detection devices capable of detecting arbitrary polarizations continues to be a challenging endeavor.Here,we demonstrate a terahertz polarization detection scheme by performing mode purity analysis and multidimensional analysis of the transmitted vortex field.The power of the proposed polarization recognition is verified by using three polarization trajectories,including linear polarizations,circular polarizations,and elliptical polarizations.Using the reconstructed complete polarization parameters,the detected polarization states are characterized using polarization ellipses,Poincarésphere,and full-Stokes parameters.The experimental results validate the power of this scheme in polarization detection.This scheme holds promise for applications in polarization imaging and terahertz communication.
基金supported by Strategic Priority Research Program of the Chinese Academy of Sciences (XDA01030501 to Haixiang Sun)National Natural Science Foundation of China (31571189, 81571391, 30900847 to Lijun Ding)+1 种基金Jiangsu Provincial Medical Youth Talent (QNRC2016006)Nanjing Medical Science Development Project (JQX14004, ZKX16042)
文摘Premature ovarian failure(POF) is a refractory disease for clinical treatment with the goal of restoring fertility. In this study,umbilical cord mesenchymal stem cells on a collagen scaffold(collagen/UC-MSCs) can activate primordial follicles in vitro via phosphorylation of FOXO3 a and FOXO1. Transplantation of collagen/UC-MSCs to the ovaries of POF patients rescued overall ovarian function, evidenced by elevated estradiol concentrations, improved follicular development, and increased number of antral follicles. Successful clinical pregnancy was achieved in women with POF after transplantation of collagen/UC-MSCs or UC-MSCs. In summary, collagen/UC-MSC transplantation may provide an effective treatment for POF.
基金supported by The Strategic Priority Research Program of the Chinese Academy of Sciences (XDA01030505)Jiangsu Provincial Key Medical Center (YXZXB2016004)+3 种基金Key Research and Development Program of Jiangsu Province (BE2016612)National Natural Science Foundation of China (81771526)Excellent Youth Natural Science Foundation of Jiangsu Province (BK20170051)Six Talent Peaks Projects in Jiangsu Province (WSW-074)
文摘Intrauterine adhesion(IUA) is a common cause of uterine infertility and one of the most severe clinical features is endometrial fibrosis namely endometrial scarring for which there are few cures currently. Blocked angiogenesis is the main pathological change in the scarred endometrium. The fibroblast growth factor 2(b FGF), a member of FGF family, is usually applied to promote healing of refractory ulcer and contributes to angiogenesis of tissues. In this study, the sustained-release system of b FGF100 μg was administrated around scarred endometrium guiding by ultrasound every 4 weeks in 18 patients(2–4 times). Results showed that after treatment, the menstrual blood volume, endometrial thickness and the scarred endometrial area were improved.Histological study showed blood vessel density increased obviously. Three patients(3/18) achieved pregnancy over 20 gestational weeks. Therefore, administrating the b FGF surrounding scarred endometrium may provide a new therapeutic approach for the patients with endometrial fibrosis.