老年人髋关节或膝关节置换术后延续护理对关节功能恢复的有效性及安全性:系统评价

目的系统评价延续护理促进老年人关节功能恢复的有效性及安全性。方法检索Cochrane Library、Web of Science、PubMed、Embase数据库中有关延续护理应用于老年关节置换患者的随机对照试验和队列研究,检索时间从建库到2023年10月25日。2名研究员独立完成文献筛选、数据提取,随机对照试验通过Cochrane偏倚风险工具进行文献偏倚分析,队列研究通过纽卡斯尔-渥太华标准进行文献质量评价。结果共纳入15篇文献,包括34186例膝关节和髋关节置换患者。促进老年髋关节置换患者功能改善的主要指标包括髋关节评分、出院后日常生活指数评分(Barthel Index)及生活质量;对老年膝关节置换患者进行延续护理明显改善的指标包括膝关节运动范围、骨关节炎指数、关节损伤和骨关节炎结果评分;延续护理对术后并发症并没有明显作用。文献质量评价显示纳入文献总体质量较高,但仅1项针对髋关节置换术后患者的研究运用了理论框架。结论延续护理在缓解膝关节疼痛、改善关节活动度及髋关节功能方面发挥了重要作用,但是对生活质量、患者满意度、经济、减少关节置换术后并发症和再次入院率方面的有效性尚需进一步明确。

铋掺杂的二氧化钌催化剂用于高效酸性水氧化

目前,电解水是一种很有前景的制氢方式,它能够将可持续能源产生的电能转化为储存在氢键中的化学能,实现高效的能源转换.与传统碱性电解槽相比,质子交换膜水电解槽(PEMWE)由于工作温度低、电压效率高、电流密度高和兼容性好,是一种很有发展潜力的绿色制氢技术.然而,PEMWE阳极析氧反应(OER)缓慢的反应动力学通常需要消耗更多能量,极大降低工作效率并限制了其发展.目前氧化铱(IrO_(2))仍然是唯一能商业应用的PEMFC阳极催化剂.但铱储量少且成本高严重阻碍了PEMFC大规模应用.近年来,氧化钌(RuO_(2))因其高固有活性且价格相对低廉被认为是IrO_(2)在酸性OER中潜在的替代品.然而,RuO_(2)在酸性OER中稳定性较差,长时间会发生晶体结构崩塌和溶解.因此,开发出一种有效的策略来平衡RuO_(2)基催化剂的稳定性和活性之间的关系对PEMWE的实际应用至关重要.本文采用铋(Bi)掺杂来调控RuO_(2)的酸性OER电催化剂(Bi_(0.15)Ru_(0.85)O_(2)),同时提高了其酸性OER的活性和稳定性.在0.5molL^(-1)H_(2)SO_(4)溶液中,Bi_(0.15)Ru_(0.85)O_(2)在10 mAcm^(-2)下酸性OER的过电位为200.0 mV,远低于RuO_(2)和商业RuO_(2),且具有长达100 h的稳定性.X射线光电子能谱(XPS)和Ru L_(2,3)边X射线吸收近边结构(XANES)结果表明,引入Bi元素后,Bi_(0.15)Ru_(0.85)O_(2)中Ru的初始氧化态升高,有利于OER过程中Ru活性中心的氧化,激活活性位点,从而提高催化活性.电化学实验、紫外光发射光谱和紫外可见光谱等结果表明,Bi_(0.15)Ru_(0.85)O_(2)比RuO_(2)具有更快的电子转移能力和更好的导电性,从而提升了催化过程的反应动力学.Bi和Ru之间的强电子相互作用也有利于提高催化剂结构的稳定性以及在OER过程中的稳定性.此外,本文还通过原位拉曼光谱研究了Bi_(0.15)Ru_(0.85)O_(2)和RuO_(2)的催化机理,更加深入地了解其构效关系.表观活化能测试和密度泛函理论结果表明,Bi的引入可以有效降低速率决定步骤的表观活化能和能垒,从而大大提升催化性能.综上所述,本文成功制备了高性能的RuO_(2)基电催化剂,并将其应用于酸性OER中.Bi_(0.15)Ru_(0.85)O_(2)中Ru活性位点的激活以及强电子相互作用有利于平衡活性和稳定性之间的关系,实现同时提高催化活性和稳定性,对酸性OER催化剂的设计提供了新思路.

Nickel single atom overcoordinated active sites to accelerate the electrochemical reaction kinetics for Li-S cathode

Lithium-sulfur(Li-S)batteries with high theoretical energy density are promising advanced energy storage devices.However,shuttling of dissolute lithium polysulfide(LiPSs)and sluggish conversion kinetics impede their applications.Herein,single nickel(Ni)atoms on two-dimensional(2D)nitrogen(N)-doped carbon with Ni-N_(4)-O overcoordinated structure(SANi-N_(4)-O/NC)are prepared and firstly used as a sulfur host of Li-S batteries.Due to the efficient polysulfides traps and highly LiPSs conversion effect of SANi-N_(4)-O/NC,the electrochemical performance of Li-S batteries obviously improved.The batteries can well operate even under high sulfur loading(5.8 mg cm^(-2))and lean electrolyte(6.1μL mg^(-1))condition.Meanwhile,density functional theory(DFT)calculations demonstrate that Ni single atom’s active sites decrease the energy barriers of conversion reactions from Li_(2)S_(8)to Li2S due to the strong interaction between SANi-N_(4)-O/NC and LiPSs.Thus,the kinetic conversion of LiPSs was accelerated and the shuttle effect is suppressed on SANi-N_(4)-O/NC host.This study provides a new design strategy for a 2D structure with single-atom overcoordinated active sites to facilitate the fast kinetic conversion of LiPSs for Li-S cathode.

蜡样芽孢杆菌性眼内炎的临床治疗观察

目的:分析外伤性蜡样芽孢杆菌性眼内炎的临床特征及抗生素敏感性,探讨早期诊治措施。方法:收集2019-01/2021-12陕西省眼科医院眼外伤中心收治的蜡样芽孢杆菌性眼内炎患者15例15眼的临床资料。记录受伤时间、受伤情况、术前视力、末次随访矫正视力、手术方式、细菌培养及药敏试验检测结果。结果:纳入患者15例15眼中,5眼单纯角膜穿通伤行伤口清创缝合联合眼内抗生素注射;10眼眼球穿通伤合并外伤性白内障及眼内异物行清创、白内障切除、眼内异物取出、玻璃体切除联合硅油填充及眼内抗生素注射。末次随访时,11眼(73%)治疗有效,眼球保留;4眼(27%)治疗无效,行眼内容物剜除。眼球保留的11眼中,视力下降1眼(9%),视力不变1眼(9%),视力提高1级4眼(36%),视力提高2级5眼(45%),治疗后视力较治疗前明显改善。相关性分析显示,病程与最终矫正视力呈负相关(r_(s)=-0.762,P=0.001)。纳入患者玻璃体液及房水样本培养均为蜡样芽孢杆菌生长,药敏试验检测均对万古霉素敏感。结论:万古霉素是治疗蜡样芽胞杆菌性眼内炎的有效药物,尽早进行玻璃体切除联合硅油填充、万古霉素玻璃体内注射是治疗蜡样芽孢杆菌眼内炎的有效方法。

Inflammatory myofibroblastic tumor diagnosed due to high intraocular pressure

Dear Editor,I am writing this letter to present an unusual case of orbital inflammatory myofibroblastic tumor(IMT)diagnosed due to high intraocular pressure(IOP).IMT is a rare mesenchymal,low-grade malignant or borderline tumor,composed of differentiated myofibroblastic spindle cells,often accompanied by plasma cells and lymphocyte infiltration[1].The onset in most patients is insidious.

Application of 16s rDNA Sequencing in the Analysis of Pathogenic Bacteria in Sputum of Severe Bacterial Pneumonia

Objective: 120 patients with severe pneumonia who were kept in the comprehensive ICU of our hospital in 2018 were selected, and 16s rDNA sequencing was performed to analyze the composition of pathogenic bacteria in the sputum of severe pneumonia. Methods: The sputum samples of patients with severe bacterial pneumonia were collected, and the diversity of pathogens in the samples was analyzed by polymerase chain reaction (PCR) amplification and high-throughput sequencing (16s rDNA PCR-DGGE). Results: Sequence showed that sputum samples contained a relatively large number of species, and there were many species that were not detected by sequencing. The dominant bacteria were Streptococcus, Sphingomonas, Corynebacterium, Denatobacteria, Aquobacteria, Acinetobacteria, Prevotella, Klebsiella, Pseudomonas, etc. Conclusion: Bacteria caused by sputum of severe bacterial pneumonia are complex and diverse, which provides new methods and ideas for individualized treatment of patients with severe pneumonia.

Application of 16S rDNA Sequencing Technology in the Analysis of Pathogenic Bacteria in Sputum of Severe Pneumonia

The diagnosis of pathogenic bacteria in severe pneumonia is difficult and the prognosis is poor. Its outcome is closely related to bacterial pathogenicity and the timeliness and pertinence of antibiotic treatment. Therefore, early diagnosis is of great significance to the prognosis of patients. Sputum examination and culture is the gold standard for the diagnosis of pathogens of severe pneumonia. However, due to the long time of bacterial culture, the early use of antibiotics, the change of bacteria species, mixed infection and other problems, the results of bacterial culture in sputum are often false negative. With the continuous application of new molecular biology techniques in clinical detection, the classification of bacteria and microorganisms has deepened from the identification of phenotypic characteristics to the classification of gene characteristics. Sequencing analysis with 16S rDNA sequencing technology has the characteristics of high sequencing flux, large amount of data obtained, short cycle, and can more comprehensively reflect the species composition of microbial community, real species distribution and abundance information. In this paper, 16S rDNA sequencing technology was used to analyze the bacterial population composition in the sputum of severe pneumonia, and to explore a new method of etiological diagnosis.

糖尿病眼底病变患者白内障术后黄斑水肿和视力情况

目的:探讨糖尿病(DM)眼底病变患者白内障术后视力及黄斑水肿情况。方法:选取2016-01/2017-09于我院治疗的白内障伴糖尿病眼底病变患者97例97眼,其中观察A组43例43眼(DM病程<5a),观察B组54例54眼(DM病程≥5a),同时选取单纯白内障患者60例60眼作为对照组,观察三组患者治疗前后最佳矫正视力(BCVA)、黄斑区视网膜厚度(中心凹区、内环区、外环区)、视网膜平均光敏感度(MS)等情况。结果:术后1mo,对照组和观察A组患者BCVA优于观察B组(0. 24±0. 09),差异均有统计学意义(P <0. 05);观察B组患者黄斑区中心凹区、内环区和外环区厚度分别为283. 30±17. 06、335. 51±20. 26、297. 28±20. 22μm,均高于观察A组和对照组,差异均有统计学意义(P<0. 05);观察B组患者MS(11. 54±1. 89dB)明显低于观察A组和对照组,差异均有统计学意义(P<0. 05)。术后3mo,对照组总渗漏率明显低于观察A组和B组,观察B组总渗漏率(55. 6%)明显高于观察A组,差异均有统计学意义(P<0. 0167)。结论:相比于单纯白内障患者,合并糖尿病眼底病变的患者术后视网膜厚度明显增加,易发生黄斑水肿,同时影响术后视力恢复,其中DM病程较长者尤其明显。

康柏西普联合复合式小梁切除术及视网膜光凝治疗新生血管性青光眼

目的:探讨玻璃体腔注射康柏西普联合复合式小梁切除术及视网膜光凝治疗新生血管性青光眼的效果和安全性。方法:回顾性分析2018-01/2020-12在我院就诊的新生血管性青光眼患者47例47眼的临床资料。随访6mo,观察患者治疗前后视力和眼压的变化情况及并发症发生情况。结果:复合式小梁切除术后6mo,本组患者视力提高25眼(53%),其中术前无光感8眼中,提高至0.2、0.02各1眼,提高至手动/30cm 2眼,从无光感恢复光感2眼;视力无变化19眼(40%);视力下降3眼(6%)。复合式小梁切除术后6mo,40例40眼未用任何降眼压药物,眼压<21mmHg,手术完全成功率为85%。复合式小梁切除术后1、7d,1、3、6mo眼压分别为15.6±6.2、12.8±5.9、14.7±5.3、17.1±6.9、18.3±6.7mmHg,与入院时眼压(46.0±11.9mmHg)和玻璃体腔注射康柏西普3d后眼压(39.9±12.5mmHg)相比有显著差异(F=106.65,P<0.001)。复合式小梁切除术后出现前房积血3眼,给予药物保守治疗后积血于3~7d完全吸收。结论:玻璃体腔注射康柏西普联合复合式小梁切除术及视网膜光凝治疗新生血管性青光眼安全、有效。

Effects of particle characteristics on the granulation ability of iron ores during the sintering process

The granulation behavior of iron ores is essential for subsequent parameter optimization and efficient granulation, especially under changing material conditions. In this study, the effects of surface properties and particle size were analyzed using a laboratory granulation method; an estimation of the granulation of sintering blends was subsequently conducted for the base ores. Circularity and porosity were observed to negatively affect the granulation of iron ores, whereas wettability positively affected the granulation and was the most influential factor, indicating that wetting of iron ores is desirable during granulation. When iron ores with complex size distributions were granulated, the equivalent surface area was the main influencing factor for coarse particles larger than 1 mm and the ratio of adhering fines to intermediates was the main factor for fine particles smaller than 1 mm. By combining the granulation of coarse and fine particles with their proportioning, we proposed a calculation method for estimating the granulation ability of sintering blends. Good verification was demonstrated with the designed schemes. The results suggest that the developed method is effective for predicting the granulation of iron ore mixtures.

Wave packet solutions in a bounded equatorial ocean and its interannual and decadal variabilities

Linearized shallow water perturbation equations with approximation in an equatorial β plane are used to obtain the analytical solution of wave packet anomalies in the upper bounded equatorial ocean. The main results are as follows. The wave packet is a superposition of eastward travelling Kelvin waves and westward travelling Rossby waves with the slowest speed, and satisfies the boundary conditions of eastern and western coasts, respectively.The decay coefficient of this solution to the north and south sides of the equator is inversely proportional only to the phase velocity of Kelvin waves in the upper water. The oscillation frequency of the wave packet, which is also the natural frequency of the ocean, is proportional to its mode number and the phase velocity of Kelvin waves and is inversely proportional to the length of the equatorial ocean in the east-west direction. The flow anomalies of the wave packet of Mode 1 most of the time appear as zonal flows with the same direction. They reach the maximum at the center of the equatorial ocean and decay rapidly away from the equator, manifested as equatorially trapped waves. The flow anomalies of the wave packet of Mode 2 appear as the zonal flows with the same direction most of the time in half of the ocean, and are always 0 at the center of the entire ocean which indicates stagnation, while decaying away from the equator with the same speed as that of Mode 1. The spatial structure and oscillation period of the wave packet solution of Mode 1 and Mode 2 are consistent with the changing periods of the surface spatial field and time coefficient of the first and second modes of complex empirical orthogonal function(EOF)analysis of flow anomalies in the actual equatorial ocean. This indicates that the solution does exist in the real ocean, and that El Ni?o-Southern Oscillation(ENSO) and Indian Ocean dipole(IOD) are both related to Mode 2.After considering the Indonesian throughflow, we can obtain the length of bounded equatorial ocean by taking the sum of that of the tropical Indian Ocean and the tropical Pacific Ocean, thus this wave packet can also explain the decadal variability(about 20 a) of the equatorial Pacific and Indian Oceans.

Recurrent abdominal liposarcoma: Analysis of 19 cases and prognostic factors

AIM: To evaluate the clinical outcome of re-operation for recurrent abdominal liposarcoma following multidis-ciplinary team cooperation. METHODS: Nineteen consecutive patients who had re-current abdominal liposarcoma underwent re-operation by the retroperitoneal sarcoma team at our institution from May 2009 to January 2012. Patient demographic and clinical data were reviewed retrospectively. Multidisciplinary team discussions were held prior to treatment, and re-operation was deemed the best treatment. The categories of the extent of resection were as follows: gross total resection (GTR), palliative resection and partial resection. Surgical techniques were divided into discrete lesion resection and combined contiguous multivisceral resection (CMR). Tumor size was determined as the largest diameter of the specimen. Patients were followed up at approximately 3-monthly intervals. For survival analysis, a univariate analysis was performed using the Kaplan-Meier method, and a multivariate analysis was performed using the Cox pro-portional hazards model. RESULTS: Nineteen patients with recurrent abdominal liposarcoma (RAL) underwent 32 re-operations at our institute. A total of 51 operations were reviewed with a total follow-up time ranging from 4 to 120 (47.4 ± 34.2) mo. The GTR rate in the CMR group was higher than that in the non-CMR group (P = 0.034). CMR was positively correlated with intra-operative bleeding (correlation coefficient = 0.514, P = 0.010). Six cases with severe postoperative complications were recorded. Patients with tumor sizes greater than 20 cm carried a significant risk of profuse intra-operative bleeding (P = 0.009). The ratio of a highly malignant subtype (de-differentiated or pleomorphic) in recurrent cases was higher compared to primary cases (P = 0.027). Both single-factor survival using the Kaplan-Meier model and multivariate analysis using the Cox proportional hazards model showed that overall survival was corre-lated with resection extent and pathological subtype (P < 0.001 and P = 0.02), however, relapse-free interval (RFI) was only correlated with resection extent (P = 0.002). CONCLUSION: Close follow-up should be conducted in patients with RAL. Early re-operation for relapse is preferred and gross resection most likely prolongs the RFI.

B_7 molecule mRNA expression in colorectal carcinoma

AIM: To observe the status of tumor-associated B7molecule mRNA expression in human colorectal cancer tissue by in situ hybridization.METHODS: The mRNA expression patterns of cancerassociated B7-1, B7H1, B7H2, ICOS in 22 specimens of human colorectal cancer tissue were monitored by in situ hybridization (ISH) with digoxin-labeled oligonucleotide probes.RESULTS: B7-1, B7H1,B7H2, ICOS mRNA were detected in both cancer cells and tumor infiltrating lymphocytes (TIL).The mRNA expression level of these molecules in tumor cells was higher than that in TIL (0.76±0.54-1.62±0.82vs 0.38±0.19-0.65±0.33, P＜0.001). There was no relationship between expression level of tested B7 family molecules and patients' sex, age, differentiation status of cancer and regional lymph node metastasis.CONCLUSION: Th2 cytokine predominant in tumor microenvironment might be related to the expression of B7H1,B7H2 co-signal molecules in tumor cells and TIL.

Influencing factors and mechanism of water absorption process of iron ores during sintering

The appropriate content and distribution of sinter moisture play an important role in the granulation of iron ores. In this study, the effects of porosity, size distribution, and particle shape on the water absorption rate （WAR） of four types of iron ores were analyzed by using the immersion method and capillary water absorption method. In addition, the mechanism underlying the water absorption process in iron ores was unraveled. It is found that the WARs of iron ores decrease quickly with the increase in water absorption time at the initial stages of water absorption. With further increase in absorption time, the WARs decrease gradually, until near 0. Iron ores with higher porosity, smaller particle size, and plate-like structure have the higher WARs. Compared with pores in the single-particle iron ore, voids among particles in the multi-particle iron oxide play an important role at the initial stages of water absorption. The water absorption mechanism of all single-particle and multi-particle iron ores analyzed in this study includes four steps, wherein the first three steps play a significant role in the sintering pro-cess.

Genetic analysis and gene mapping of a dwarf and liguleless mutation in barley

Leaf development underlies crop growth and productivity and has been a major target of crop domestication and improvement.However,most genes controlling leaf development in barley remain unknown.We identified a dwarf and liguleless(dl)mutant derived by ethylmethane sulfonate mutagenesis.The dl mutant showed dramatic changes in shoot architecture compared with wild-type(Yangnongpi 5)plants.Besides lacking ligules,the dl mutant showed much shorter plant height(28 cm)than Yangnongpi 5(78 cm).By map-based cloning,the dl gene was localized to a 56.58-kb genomic interval on the long arm of chromosome 7.A C-to-T single-nucleotide substitution was identified at exon position 790,and is a functional mutation resulting in a proline-to-serine substitution at the 264th amino acid residue of HORVU7Hr1G106960.Consequently,HORVU7Hr1G106960 was identified as the DL gene,encoding 269 amino acids and containing the Arabidopsis LSH1 and Oryza G1(ALOG)domain.DL is highly similar to rice OsG1-LIKE 1/2(OsG1L1/2)and sorghum AWN1/AWN1-10 at the amino acid level.Although the dl mutant allele showed no expression changes in selected tissues by real-time PCR,we propose HORVU7Hr1G106960 as a candidate gene conferring the dwarf and liguleless phenotype in barley.

An unusual case of malignant glaucoma with ciliary detachment

Citation:Xu QQ,Wang WW,Zhu J,Liu JR.An unusual case of malignant glaucoma with ciliary detachment.Int J Ophthalmol 2021;14(12):1988-1992 Dear Editor,I am writing this letter to present an unusual case of malignant glaucoma with ciliary detachment.Malignant glaucoma has an incidence of 0.6%-4%and mostly occurs after filtering surgery for primary angle-closure glaucoma.After surgery,the intraocular pressure(IOP)does not decrease but increases,and the anterior chamber(AC)becomes shallower or disappears.There is an obvious ophthalmodynia,and the disease rapidly worsens,thus seriously threatening the visual function of patients[1-3].So far,no cases of malignant glaucoma combined with ciliary detachment have been reported.Complete comprehension of the symptoms of malignant glaucoma with ciliary detachment is crucial for preserving the patients’visual function,diagnosing the disease at the early stage,and conducting correct and effective treatment.

Identification of in situ Generated Iron-Vacancy Induced Oxygen Evolution Reaction Kinetics on Cobalt Iron Oxyhydroxide

Developing highly efficient and low-cost electrocatalysts towards oxygen evolution reaction(OER)is essential for practical application in water electrolyzers and rechargeable metal-air batteries.Although Fe-based oxyhydroxides are regarded as state-of-the-art non-noble OER electrocatalysts,the origin of performance enhancement derived from Fe doping remains a hot topic of considerable discussion.Herein,we demonstrate that in situ generated Fe vacancies in the pristine CoFeOOH catalyst through a pre-conversion process during alkaline OER result from dynamic Fe dissolution,identifying the origin of Fe-vacancy-induced enhanced OER kinetics.Density functional theory(DFT)calculations and experimental results including X-ray absorption fine-structure spectroscopy,in situ UV-Vis spectroscopy,and in situ Raman spectroscopy reveal that the Fe vacancies could significantly promote the d-band center and valence states of adjacent Co sites,alter the active site from Fe atom to Co atom,accelerate the formation of high-valent active Co^(4+)species,and reduce the energy barrier of the potential-determining step,thereby contribute to the significantly enhanced OER performance.

大麦NF-YC基因鉴定及在盐胁迫下的表达分析

核因子Y(NF-Y)是由NF-YA、NF-YB和NF-YC三个亚基组成的一类真核细胞转录因子,主要参与植物生长发育调控和非生物胁迫信号传递。该研究利用生物信息学方法解析了大麦(Hordeum vulgare)NF-YC基因家族功能。首先,基于大麦基因组数据库鉴定出11个HvNF-YC成员,分布在除第2号染色体以外的其余6条染色体上,内含子0–5个。系统进化分析显示,大麦、拟南芥(Arabidopsis thaliana)和水稻(Oryza sativa)NF-YC基因家族成员可分为5个亚家族。基因复制分析显示,6个HvNF-YC基因存在片段复制,3个HvNF-YC基因存在串联复制。启动子顺式作用元件分析显示,大多数HvNF-YC基因启动子含有与非生物胁迫及激素响应相关的顺式作用元件。对HvNF-YC家族成员在不同组织不同时期的表达模式分析表明,不同成员的时空表达存在明显差异,其中HvNF-YC9和HvNF-YC11可能在籽粒发育初期发挥重要作用。通过分析耐盐型和盐敏感型大麦品种根和叶中HvNF-YC表达量变化,发现HvNF-YC3、HvNF-YC6和HvNF-YC10主要在盐胁迫初期的根中行使功能,HvNF-YC9主要在长期盐胁迫处理后期的根中起作用。综上所述,推测HvNF-YC9、10、11三个基因可作为后续探究大麦NF-YC参与耐盐作用机制的候选基因。该研究结果为进一步解析HvNF-YC在大麦中的耐盐调控功能奠定了基础。

桑树幼苗根系表现出的性别二态性取决于相邻植株的性别

雌雄异株植物通常呈现性别二态性,但其雌株和雄株的根系性状和养分吸收如何响应相邻植株的性别变化尚不清楚。本研究以中国广泛栽培的雌雄异株植物桑树(Morus alba)为试验对象,在水培环境下,采取雌-雌、雄-雄和雌-雄3种组合种植模式进行试验。植株生长3个月后,分别测定雌雄植株根系的解剖结构、形态、营养浓度和生物量。研究结果表明,在水培环境中,与同性相邻相比,当桑树雄株与异性相邻时,其根系木质部变小,根和径生物量减少,根系中N、P、K浓度增加。相比,当桑树雌株与异性相邻时,其根系木质部变大,细根长度、表面积和体积以及根系δ^(13)C和N、P、K浓度增加。雌雄植株根系δ^(13)C和N、P、K浓度的变化与根系性状的改变有关。这些结果表明,相邻植株的性别影响了雌雄桑树根系解剖结构和形态。同时,雌雄植株对相邻植株性别改变的响应呈现性别二态性,这种二态性响应影响了雌雄植株水分利用效率和营养吸收。这些发现对于理解森林和自然系统中其它雌雄异株物种的种群动态变化具有重要意义。

Ni_(3)N Modified MOF Heterostructure with Tailored Electronic Structure for Efficient Overall Water Splitting

Exploring bifunctional electrocatalysts with high-efficiency and stability toward overall water splitting is desirable for sustainable energy technologies,yet challenging.Herein,we report the construction of Ni_(3)N on the surface of Ni-MOF-74 through an in-situ nitriding process.The obtained Ni-MOF-74/Ni_(3)N exhibits remarkable HER activity with an overpotential of 73 mV to deliver 10 mA cm^(-2).Theoretical calculations and experimental study demonstrate the electron transport between Ni_(3)N and Ni-MOF-74,leading to the improved H_(2)O adsorption,optimized hydrogen adsorption,and increased H_(ad)diffusion,which contributes to the enhanced HER performance.Besides,the obtained Ni-MOF-74/Ni_(3)N also possesses outstanding activity toward OER and overall water splitting.