1例误诊为原发性精神病的额颞叶痴呆病例讨论

目的:报道1例早期误诊为原发性精神病的额颞叶痴呆患者诊疗过程并进行讨论分析。方法:对1例行为变异型额颞叶痴呆患者的临床和神经影像学表现进行分析。结果:本病例为中年女性,首发表现为精神异常,在外院先后诊断为抑郁症、精神分裂症,予药物治疗后效果不佳,行头颅MRI示双侧额颞叶萎缩,左侧明显。头颅18F-FDG PET示:双侧侧额叶、颞叶外侧代谢减低。FTD相关基因检测发现该患者存在易感基因突变。结论:这是1例典型的bvFTD病例,早期被误诊为原发性精神病,这提示在精神异常的诊断过程中,需与bvFTD鉴别诊断。

Avalanche photodiodes on silicon photonics

Silicon photonics technology has drawn significant interest due to its potential for compact and high-performance photonic integrated circuits.The Ge-or III-V material-based avalanche photodiodes integrated on silicon photonics provide ideal high sensitivity optical receivers for telecommunication wavelengths.Herein,the last advances of monolithic and hetero-geneous avalanche photodiodes on silicon are reviewed,including different device structures and semiconductor systems.

燃料电池多孔碳载体高石墨化的超快速碳热冲击策略

质子交换膜燃料电池(PEMFC)具有能源转换效率高、清洁环保等优点,是新能源技术的重要发展方向.目前,燃料电池中主要使用的电催化剂是碳载铂或铂合金,碳载体不仅增强催化剂活性,提高贵金属利用率,而且对催化剂的耐久性起着至关重要的影响.但常规的碳载体在燃料电池强腐蚀环境中容易发生腐蚀,进而导致催化剂颗粒脱落和团聚,活性衰减.近年来,研究发现提高碳载体石墨化程度有利于增强载体的耐腐蚀能力,提高催化剂的稳定性.常规的高温热处理难以大幅提高载体的石墨化,且长时间的高温处理易导致原始碳结构的坍塌或转变以及比表面积显著下降.因此,迫切需要发展新的策略或技术经济、高效地提高碳载体的石墨化度,并且保持碳载体原始结构和形貌.本文提出了一种快速且低成本的碳热冲击方法,用于多孔碳材料的石墨化处理,包括碗状碳(BC)、空心碳球、ZIF-8衍生碳和商业炭黑等.其中,以碗状碳为研究对象,即将碗状碳载体与石墨化催化剂氯化铁通过超声共混,干燥后放入加热源碳毡中,通过快速碳热冲击,3 s内升温至1300℃,在该温度保温30 s后,3 s降至室温,最后酸洗得到高石墨化碗状碳.作为对照,含有氯化铁的碗状碳也在普通管式炉中石墨化处理.采用X射线衍射(XRD)、Raman光谱、四探针电导率测试、氮气吸脱附曲线、扫描电镜(SEM)和透射电镜等表征手段对所得的石墨化碗状碳进行表征.同时,以碳热冲击所得的高石墨化碗状碳为载体合成了碳载的Pt Co金属间化合物催化剂(PtCo/G-BC-S),并通过旋转圆盘电极及单电池考察其电催化性能.XRD、Raman光谱、电导率测试和SEM结果表明,碳热冲击处理后的碗状碳具有高的石墨化程度,其电导率高达5.7 S cm^(–2)(20 MPa下),为原始碗状碳的7倍,同时依然维持原有碗状结构.而对于普通管式炉煅烧后的碗状碳,虽然石墨化程度得到提高,但其结构出现了严重的坍塌,且比表面积下降严重.电化学测试结果表明,PtCo/G-BC-S表现出较好的ORR催化性能,在高电位(1.0–1.5 V)下G-BC-S具有高的耐腐蚀性能:PtCo/G-BC-S的半波电位(0.933 V)均高于Pt Co/BC(0.928 V)和商业Pt/C(0.89 V).此外,高电位下的加速耐久性测试结果表明,PtCo/G-BC-S的半波电位只衰减了13 mV,而PtCo/BC和商业Pt/C分别衰减了22 mV和47 mV.以上研究结果表明,PtCo/G-BC-S催化剂的高活性和稳定性来自于两个方面:铂钴金属间化合物催化剂的高活性和化学/结构稳定性,以及碗状碳载体的高石墨化度和多孔结构.提高碳载体的耐久性对燃料电池的稳定性至关重要,其中通过提高石墨化来缓解碳腐蚀是重要方法之一.综上,本文为制备高耐久性碳载体提供了一种高效、经济的策略,对推动燃料电池的发展具有借鉴意义.

Nickel-Carnosine complex:A new carrier for enzymes immobilization by affinity adsorption

Immobilization is an effective method to promote the application of enzyme industry for improving the stability and realizing recovery of enzyme.To some extent,the performance of immobilized enzyme depends on the choice of carrier material.Therefore,the development of new carrier materials has been one of the key issues concerned by enzyme immobilization researchers.In this work,a novel organic–inorganic hybrid material,nickel-carnosine complex(NiCar),was synthesized for the first time by solvothermal method.The obtained NiCar exhibits spherical morphology,hierarchical porosity and abundant unsaturated coordination nickel ions,which provide excellent anchoring sites for the immobilization of proteins.His-tagged organophosphate-degrading enzyme(Opd A)and x-transaminase(ω-TA)were used as model enzymes to evaluate the performance of NiCar as a carrier.By a simple adsorption process,the enzyme molecules can be fixed on the particles of NiCar,and the stability and reusability are significantly improved.The analysis of protein adsorption on NiCar verified that the affinity adsorption between the imidazole functional group on the protein and the unsaturated coordination nickel ions on NiCar was the main force in the immobilization process,which provided an idea way for the development of new enzyme immobilization carriers.

New secondary metabolites with cytotoxicity from fungus Penicillium roqueforti

Two novel compounds including a cyclohelminthol type polyketide(namely oxaleimide K,1)and a maleimide deriva-tive(namely peniroquefortine A,2),and a new natural product(namely 2-(acetylamino)-N-[(1E)-2-phenylethenyl]-acetamide,3),together with four known compounds(4-7),were isolated and identified from fungus Penicillium roqueforti,which was separated from the root soil of Hypericum beanii N.Robson collected from the Shennongjia For-estry District,Hubei Province.Their structures including absolute configurations were mainly established by the NMR spectroscopy analyses and single-crystal X-ray diffraction experiment.Compound 1 represents the second example of a cyclohelminthol type polyketide,which features a rare 6/6/5/5 tetracyclic system and a branched aliphatic chain containing a terminal olefin(oct-1-en-3-yl)moiety,and compound 2 possesses an unprecedented carbon skeleton that is uniquely defined by a maleimide moiety linked to the respective 4-methylene-2-(3-methylbut-2-en-1-yl)-phenol and para-substituted aromatic moieties via the carbon-carbon bonds.Remarkably,the absolute configuration of a cyclohelminthol type polyketide as exemplified by compound 1 is determined by the single-crystal diffraction analysis for the first time,highlighting an E-configuration for the linkage of a succinimide moiety and a tetrahydro-furan moiety for 1 rather than a Z-configuration as previously reported in the biosynthesis study,which gives a new insight into the structural elucidation of this category of polyketides.Additionally,compound 1 exhibited significant cytotoxic activity against multiple tumor cells,especially against the Farage and SU-DHL-2 cells(IC_(50)<20μM,48 h).Further mechanism study revealed that compound 1 significantly induced cell cycle arrest in Farage and SU-DHL-2 cells by causing abnormal ROS level and triggering oxidative stress.

Effect of Polysaccharides from Hedyotis diffusa on Immune Cells of Small Intestinal Mucosa of Chicks

[Objectives]This study aimed to investigate the effect of polysaccharides from Hedyotis diffusa on the immune cells of the intestinal mucosa of chicks.[Methods]Total 200 seven-day-old AA chicks were evenly and randomly divided into four groups:control group and three treatment groups.The chicks in the control group(group I)were fed basal diet,and those in the treatment groups were fed with basal diet supplemented with 0.4(group II),0.8(group III)and 1.2(group IV)g/kg H.diffusa polysaccharides(OPS),respectively.At the age of 14,28 and 42 d,10 chicks from each of the groups were sacrificed,respectively for counting of intraepithelial lymphocytes(IELs)and lamina propria secretory IgA(SIgA)positive cells in small intestinal mucosa.[Results]At the age of 14 d,the duodenal and jejunal IEL and SIgA positive cell counts in groups II,III and IV were significantly greater than those in group I(P<0.05).At the age of 28 d,the jejunal IEL count of group IV was significantly lower than those of groups I,II and III(P<0.05);and there was no significant difference in IEL or SIgA positive cell count between group I and the other groups(P>0.05).At the age of 42 d,the duodenal and jejunal IEL counts in group II were significantly greater than those in groups I,III and IV(P<0.05),while the differences in duodenal and jejunal IEL count between groups III,IV and I were insignificant(P>0.05).The duodenal SIgA positive cell counts in the treatment groups were insignificantly different from that in group I(P>0.05).The jejunal SIgA positive cell count in group II was significantly greater than those in groups I,III and IV(P<0.05).There was no significant difference in jejunal SIgA positive cell count between groups III and IV and group I(P>0.05).[Conclusions]OPS at 0.4 g/kg can promote the proliferation of immune cells in the small intestine mucosa of 14-42-day-old AA chicks,and it is recommended to be added to the feed.

Effects of Oldenlandia diffusa Polysaccharides on the Structures of Chick Small Intestine Tissues

In order to explore the application effect of Oldenlandia polysaccharides(OPS)in the production of AA broilers,2007-day-old AA broilers were randomly divided into 4 groups,namely groups Ⅰ,Ⅱ,Ⅲ,and Ⅳ,each including 50 chicks.The control group(group Ⅰ)was fed with basal diet;and the 3 experimental groups were fed based on the basal diet with the addition of OPS at 0.4 g/kg(group Ⅱ),0.8 g/kg(group Ⅲ),and 1.2 g/kg(group Ⅳ)feed for 1 week,respectively,and then fed the basal diet for 4 weeks.At the ages of 14,28,and 42 d,10 chickens were put into death in the control group and the experimental groups,respectively,and the duodenum and jejunum tissue samples were collected for the analysis of the effects of OPS on the structures of chick intestines.The results showed that at the age of 14 d,the villus lengths of duodenum and jejunum in groups Ⅱ,Ⅲ,and Ⅳ were significantly greater than those in group Ⅰ(P<0.05),and the ratios of duodenal or jejunal villus length to crypt depth in groups Ⅱ and Ⅲ were significantly greater than that in group Ⅰ(P<0.05);at the age of 28 d,the villus length of duodenum in group Ⅱ was significantly greater than that in group Ⅰ(P<0.05);and at the age of 42 d,the ratios of jejunual villus length to crypt depth in groups Ⅱ,Ⅲ and Ⅳ were significantly larger than those of group I(P<0.05).It showed that OPS could promote the small intestine development of AA broilers aged 14 to 42 d.

Polysaccharides from Huidouba and Its Effect on Type-2 Diabetes Mellitus

To evaluate the extraction process of Huidouba polysaccharides(HDBP)and its anti-diabetic activity,this study focused on the two contents as follows:extraction process of HDBP,which was optimized by orthogonal experiments using the extraction ratio of HDBP for the index;and bioactivity evaluation of HDBP on streptozotocin-induced diabetic rat model based on the histological,biochemical and enzyme linked immunosorbent assay(ELISA)method for histological observation,physiological and biochemical index such as fasting blood glucose(FBG),nitric oxide(NO),malondialdehyde(MDA),super oxide dismutase(SOD)and insulin level detection in pancreas tissue respectively.The results showed that HDBP extraction ratio was the highest under following conditions:the extraction temperature at 90℃,the extraction time of 1.5 h,and the solid-liquid ratio at 1:10.Compared with the normal control group and the model group,histological observation,physiological and biochemical index and insulin level in pancreas tissue significantly increased and FBG significantly decreased according to the dosage administrated.HDBP affected Streptozotocin-induced diabetic rats.

考虑电池损耗的电动物流汽车充电设施选址与充电策略协同优化研究

由于政府的大力支持和社会公众环保意识的增强,电动汽车在物流领域的应用得到了广泛的关注。不同于传统物流车辆,电动汽车运营成本受到电池损耗等因素的影响。本文以电池损耗模型为基础,建立了电动汽车充电设施选址与充电策略协同优化问题的整数规划模型。针对上述问题,本文提出了基于自适应大邻域搜索的混合启发式算法(SIGALNS),改进算子提升算法求解效率。随后,通过算例分析验证了模型的准确性和算法的有效性。研究结果表明,考虑电池损耗成本的电动汽车网络优化策略有利于降低物流企业运营成本,与其实际需要更为契合。

Enzyme@silica nanoflower@metal-organic framework hybrids： A novel type of integrated nanobiocatalysts with improved stability

A novel integrated nanobiocatalyst system based on an enzyme@silica nanoflower@metal-organic framework （enzyme@SNF@ZIF-8） structure with improved stability is fabricated for the first time. The versatility of this system is validated using penicillin G acylase （PGA） and catalase （CAT） as model enzymes. The microporous ZIF-8 layer can be controlled by varying the number of ZIF-8 coating cycles, which produces PGA@SNF@ZIF-8 nanobiocatalysts with different ZIF-8 layer thicknesses. After the second ZIF-8 coating cycle, a PGA@SNF@ZIF-8（2） structure with a homogeneous and well-intergrown ZIF-8 layer is formed, which possesses excellent mechanical and chemical stability. Moreover, PGA@SNF@ZIF-8（2） shows improved thermal/storage stability and reusability compared with free PGA and PGA immobilized on silica nanoflowers （PGA@SNF）. The obtained CAT-based nanobiocatalysts （CAT@SNF@ZIF-8（2）） also show excellent catalytic performance.

Hydrologic balance, net primary productivity and water use efficiency of the introduced exotic Eucalyptus grandis × Eucalyptus urophylla plantation in south-western China

Aims Land cover changes can disrupt water balance and alter the partitioning of precipitation into surface runoff,evapotranspiration and groundwater recharge.The widely planted Eucalyptus trees in south-western China have the potential to bring about hydrologic impacts.Our research aims to elucidate the hydrologic balance characteristics of the introduced exotic Eucalyptus grandis×Eucalyptus urophylla plantation and to assess whether its high productivity results from high water use efficiency(WUE)or large water consumption.Methods A 400-m^(2) experimental plot was established in an E.grandis×E.urophylla plantation in south-western China.Water balance components,including stand transpiration(T_(r)),evapotranspiration(E_(t))and runoff(R)were obtained as follows:T_(r) was estimated based on sap flow measurements,E_(t) was estimated as the average of surface transpiration and evaporation weighted by the fractional green vegetation cover using a modeling approach,and R was collected using the installed metal frame.Net primary productivity(NPP)was obtained from allometric equation and annual diameter at breast height(DBH)increment determination.Important Findings Annual E_(t) and T_(r) were 430±31 and 239±17 mm,respectively.Annual T_(r) accounts for 56±8%of total evapotranspiration on average.WUE(NPP/T_(r))of the E.grandis×E.urophylla was estimated to be 3.3–3.9 mmol·mol^(−1).Based on the comparative analysis of T_(r) and WUE,E.grandis×E.urophylla had a high productivity due to its high WUE without exhibiting prodigal water use.Meteorological factors including vapor pressure deficit and global solar radiation(R_(s))were key factors regulating E_(t) and T_(r) in our research site.Annual surface runoff,E_(t) and canopy interception occupied 7%,27–30%and 16%of total precipitation,while the remaining 46–50%of precipitation was used for sustaining groundwater recharge and altering soil water storage.The higher runoff coefficient(7.1%)indicated the weaker capability of E.grandis×E.urophylla to reserve water resource than natural forests and less disturbed plantations.The planting and protection of understory vegetation may decrease the surface runoff and exert beneficial effects on water conservation capacity of Eucalyptus plantation.

Mechanisms of enhanced sub-bandgap absorption in high-speed all-silicon avalanche photodiodes

All-silicon (Si) photodiodes have drawn significant interest due to their single and simple material system and perfect compatibility with complementary metal-oxide semiconductor photonics. With the help from a cavity enhancement effect, many of these photodiodes have shown considerably high responsivity at telecommunication wavelengths such as 1310 nm, yet the mechanisms for such high responsivity remain unexplained. In this work,an all-Si microring is studied systematically as a photodiode to unfold the various absorption mechanisms.At-6.4 V, the microring exhibits responsivity up to0.53 A∕W with avalanche gain, a 3 dB bandwidth of25.5 GHz, and open-eye diagrams up to 100 Gb/s. The measured results reveal the hybrid absorption mechanisms inside the device. A comprehensive model is reported to describe its working principle, which can guide future designs and make the all-Si microring photodiode a promising building block in Si photonics.

64 Gb/s low-voltage waveguide SiGe avalanche photodiodes with distributed Bragg reflectors

We demonstrate low-voltage waveguide silicon-germanium avalanche photodiodes(APDs)integrated with distributed Bragg reflectors(DBRs).The internal quantum efficiency is improved from 60%to 90%at 1550 nm assisted with DBRs while still achieving a 25 GHz bandwidth.A low breakdown voltage of 10 V and a gain bandwidth product of near 500 GHz are obtained.APDs with DBRs at a data rate of 64 Gb/s pulse amplitude modulation with four levels(PAM4)show a 30%–40%increase in optical modulation amplitude(OMA)compared to APDs with no DBR.A sensitivity of around-13 d Bm at a data rate of 64 Gb/s PAM4 and a bit error rate of 2.4×10^-4 is realized for APDs with DBRs,which improves the sensitivity by^2 d B compared to APDs with no DBR.

Mechanical Properties of Resistance Spot Welded Components of High Strength Austenitic Stainless Steel

Resistance multi-spot welding （MSW） in column, triangle and tetragonal symmetry arrangements was prepared using cold-rolled 301L high-strength sheets, and their static and fatigue properties were in- vestigated. The effects of spot welds on the fracture strengths and fatigue limits were discussed. The results show that the static strengths can be estimated using an inherent linear relationship formula of the load versus the welding area. It was based on the 28%-33% volume fraction of α′ martensite induced at the interfacial spot weld fracture because of the failure deformation. The fatigue limits of the MSW nonlin- early increase with the number of spot welds. The arrangement of spot welds in the MSW significantly affects the average fatigue limit of each spot weld; its 26% maximum reduction occurred in the triangle, and the interaction stress between spot welds led to its 18% reduction in the tetragonal symmetry. The calculated fatigue stress of all MSW loadings with their mean fatigue limits was 230-270 MPa.

Autographa Californica Multiple Nucleopolyhedrovirus P48(Ac103) Is Required for the Efficient Formation of Virus-Induced Intranuclear Microvesicles

Our previous study has shown that the Autographa californica multiple nucleopolyhedrovirus(AcMNPV) p48(ac103)gene is essential for the nuclear egress of nucleocapsids and the formation of occlusion-derived virions(ODVs). However,the exact role of p48 in the morphogenesis of ODVs remains unknown. In this study, we demonstrated that p48 was required for the efficient formation of intranuclear microvesicles. To further understand its functional role in intranuclear microvesicle formation, we characterized the distribution of the P48 protein, which was found to be associated with the nucleocapsid and envelope fractions of both budded virions and ODVs. In Ac MNPV-infected cells, P48 was predominantly localized to nucleocapsids in the virogenic stroma and the nucleocapsids enveloped in ODVs, with a limited but discernible distribution in the plasma membrane, nuclear envelope, intranuclear microvesicles, and ODV envelope. Furthermore,coimmunoprecipitation assays showed that among the viral proteins required for intranuclear microvesicle formation, P48 associated with Ac93 in the absence of viral infection.

Introduction of temperature-sensitive helper and donor plasmids into Bac-to-Bac baculovirus expression systems

In the baculovirus shuttle vector(bacmid) system, a helper plasmid and a donor plasmid are employed to insert heterologous genes into a cloned baculovirus genome via Tn7 transposition in Escherichia coli. The helper and donor plasmids are usually cotransfected with constructed bacmids into insect cells, which will lead to integration of these plasmids into the viral genome,and hence to the production of defective virions. In this study, to facilitate the preparation of plasmid-free recombinant bacmids, we modified a set of helper and donor plasmids by replacing their replication origins with that of a temperature-sensitive(ts) plasmid, p SIM6. Using the resulting ts helper plasmid p MON7124 ts and the ts donor plasmid p FB1ts-PH-GFP, a recombinant bacmid,b Ac WT-PG(-), was constructed, and the transposition efficiency was found to be 33.1%. The plasmids were then removed by culturing at 37 °C. For b Ac WT-PG(-), the infectious progeny virus titer and the protein expression level under the control of the polyhedrin promoter were similar to those of a bacmid constructed with unmodified helper and donor plasmids. These ts plasmids will be useful for obtaining plasmid-free bacmids for both heterologous protein production and fundamental studies of baculovirus biology.

The role of accounting conservatism in M&A target selection

Mergers and acquisitions(M&As)are among the most important investment activities for companies,but they contain great risks.We investigate the role of accounting conservatism in M&A target selection and risk.We find that for risk-averse reasons,firms with high accounting conservatism are likely to acquire profitable targets and avoid loss-making targets.When such firms acquire loss-making targets,the conservatism’s risk-control role reduces M&A risk and increases M&A performance,but only when control of the target is transferred and the acquirer has high long-term debt and low management power.Furthermore,accounting conservatism reduces risk by increasing the maturity match between cash flow and debt.Our results suggest that accounting conservatism plays not only a risk-averse role but also a riskcontrol role,providing new evidence for the usefulness of accounting conservatism in M&A decisions.