Dendroclimatological study of Sabina saltuaria and Abies faxoniana in the mixed forests of the Qionglai Mountains,eastern Tibetan Plateau

Tree-ring chronologies were developed for Sabina saltuaria and Abies faxoniana in mixed forests in the Qionglai Mountains of the eastern Tibetan Plateau.Climate-growth relationship analysis indicated that the two co-exist-ing species reponded similarly to climate factors,although S.saltuaria was more sensitive than A.faxoniana.The strong-est correlation was between S.saltuaria chronology and regional mean temperatures from June to November.Based on this relationship,a regional mean temperature from June to November for the period 1605-2016 was constructed.Reconstruction explained 37.3%of the temperature variance during th period 1961-2016.Six major warm periods and five major cold periods were identified.Spectral analysis detected significant interannual and multi-decadal cycles.Reconstruction also revealed the influence of the Atlantic Multi-decadal Oscillation,confirming its importance on climate change on the eastern Tibetan Plateau.

Exploring the autophagy-related pathogenesis of active ulcerative colitis

BACKGROUND The pathogenesis of ulcerative colitis(UC)is complex,and recent therapeutic advances remain unable to fully alleviate the condition.AIM To inform the development of novel UC treatments,bioinformatics was used to explore the autophagy-related pathogenesis associated with the active phase of UC.METHODS The GEO database was searched for UC-related datasets that included healthy controls who met the screening criteria.Differential analysis was conducted to obtain differentially expressed genes(DEGs).Au-tophagy-related targets were collected and intersected with the DEGs to identiy differentially expressed autophagy-related genes(DEARGs)associated with active UC.DEARGs were then subjected to KEGG,GO,and DisGeNET disease enrichment analyses using R software.Differential analysis of immune infiltrating cells was performed using the CiberSort algorithm.The least absolute shrinkage and selection operator algorithm and protein-protein interaction network were used to narrow down the DEARGs,and the top five targets in the Dgree ranking were designated as core targets.RESULTS A total of 4822 DEGs were obtained,of which 58 were classified as DEARGs.SERPINA1,BAG3,HSPA5,CASP1,and CX3CL1 were identified as core targets.GO enrichment analysis revealed that DEARGs were primarily enriched in processes related to autophagy regulation and macroautophagy.KEGG enrichment analysis showed that DEARGs were predominantly associated with NOD-like receptor signaling and other signaling pathways.Disease enrichment analysis indicated that DEARGs were significantly linked to diseases such as malignant glioma and middle cerebral artery occlusion.Immune infiltration analysis demonstrated a higher presence of immune cells like activated memory CD4 T cells and follicular helper T cells in active UC patients than in healthy controls.CONCLUSION Autophagy is closely related to the active phase of UC and the potential targets obtained from the analysis in this study may provide new insight into the treatment of active UC patients.

Associations of serum D-dimer and glycosylated hemoglobin levels with third-trimester fetal growth restriction in gestational diabetes mellitus

BACKGROUND Gestational diabetes mellitus(GDM)is a special type of diabetes that commonly occurs in women during pregnancy and involves impaired glucose tolerance and abnormal glucose metabolism;GDM is diagnosed for the first time during pregnancy and can affect fetal growth and development.AIM To investigate the associations of serum D-dimer(D-D)and glycosylated hemoglobin(HbA1c)levels with third-trimester fetal growth restriction(FGR)in GDM patients.METHODS The clinical data of 164 pregnant women who were diagnosed with GDM and delivered at the Obstetrics and Gynecology Hospital of Fudan University from January 2021 to January 2023 were analyzed retrospectively.Among these women,63 whose fetuses had FGR were included in the FGR group,and 101 women whose fetuses had normal body weights were included in the normal body weight group(normal group).Fasting venous blood samples were collected from the elbow at 28-30 wk gestation and 1-3 d before delivery to measure serum D-D and HbA1c levels for comparative analysis.The diagnostic value of serum D-D and HbA1c levels for FGR was evaluated by receiver operating characteristic analysis,and the influencing factors of third-trimester FGR in GDM patients were analyzed by logistic regression.RESULTS Serum fasting blood glucose,fasting insulin,D-D and HbA1c levels were significantly greater in the FGR group than in the normal group,while the homeostasis model assessment of insulin resistance values were lower(P<0.05).Regarding the diagnosis of FGR based on serum D-D and HbA1c levels,the areas under the curves(AUCs)were 0.826 and 0.848,the cutoff values were 3.04 mg/L and 5.80%,the sensitivities were 81.0%and 79.4%,and the specificities were 88.1%and 87.1%,respectively.The AUC of serum D-D plus HbA1c levels for diagnosing FGR was 0.928,and the sensitivity and specificity were 84.1%and 91.1%,respectively.High D-D and HbA1c levels were risk factors for third-trimester FGR in GDM patients(P<0.05).CONCLUSION D-D and HbA1c levels can indicate the occurrence of FGR in GDM patients in the third trimester of pregnancy to some extent,and their combination can be used as an important index for the early prediction of FGR.

农业机械底盘智能化发展现状与展望

农机底盘技术是智能农机装备的关键技术,也是影响农业农村现代化的关键技术。欧美农场化、集约化的种植场景和雄厚的工业基础的先天优势使美西方在智能农机领域领先于我国,我国农机底盘的适应性差、智能化程度不足、舒适性差以及安全系数低。为此,从智能驱动、高适应性行走和自主作业三个方面对未来农业机械底盘智能化发展的方向进行思考和展望。着重归纳液压提升、动力换挡、无级变速、可变轮距、线控转向以及无人驾驶等新技术在农业机械底盘上应用的进展,并结合我国实际应用情况阐述农机底盘各系统相关技术的基本原理与特点,最后根据国内外农机底盘的研究进展和国内外的差距,从强化电液压技术与E-CVT的研发与升级、推动多向行走与线控转向技术的落地、实现智能化控制与无人作业等方面为未来智能农机底盘研究设计以及农业农村现代化发展提供参考。

基于柿子提取物的自制pH检测剂和酸碱变色科普实验

利用柿子提取物中的表没食子儿茶素没食子酸酯(EGCG)与硫酸亚铁的配位反应,研究配合物溶液对不同pH的响应变化,实现对生活中常见的具有酸碱性物质的便携区分应用。本实验原料简单易得、过程安全、现象明显,能让观众们感受到化学变化之美,激发对化学学科的浓厚兴趣。

Cu-石墨炔/双金属钨酸盐S型异质结协同增强光催化析氢

采用有机法和水热法合成了Cu-石墨炔和CoNiWO_(4)并构建Cu-石墨炔/CoNiWO_(4)S型异质结。在保留催化剂强氧化还原能力的同时,通过内建电场和能带弯曲的协同作用促进了光生载流子的高效分离和转移。Cu-石墨炔的引入有效提高了复合催化剂的光吸收能力和导电性,抑制了光生载流子的复合。同时,Cu-石墨炔独特的二维平面网络结构提供了丰富的活性位点,从而促进了光催化反应的进行。密度泛函理论(DFT)计算表明,Cu的表面等离子体共振效应产生的热电子转移到石墨炔上,促进氢气的析出。本研究为Cu-石墨炔和镍钴基催化剂在光催化制氢领域提供了新的参考。

April-September minimum temperature reconstruction based on Sabina tibetica ring-width chronology in the central eastern Tibetan Plateau,China

Minimum temperatures have remarkable impacts on tree growth at high-elevation sites on the Tibetan Plateau,but the shortage of long-term and high-resolution paleoclimate records inhibits understanding of recent minimum temperature anomalies.In this study,a warm season(April–September)reconstruction is presented for the past 467 years(1550–2016)based on Sabina tibetica ring-width chronology on the Lianbaoyeze Mountain of the central eastern Tibetan Plateau.Eight warm periods and eight cold periods were identified.Long-term minimum temperature variations revealed a high degree of coherence with nearby reconstructions.Spatial correlations between our reconstruction and global sea surface temperatures suggest that warm season minimum temperature anomalies in the central eastern Tibetan Plateau were strongly influenced by large-scale ocean atmospheric circulations,such as the El Ni?o-Southern Oscillation and the Atlantic Multidecadal Oscillation.

Atomically dispersed Fe sites on hierarchically porous carbon nanoplates for oxygen reduction reaction

Developing cost-effective,robust and stable non-precious metal catalysts for oxygen reduction reaction(ORR) is of paramount importance for electrochemical energy conversion devices such as fuel cells and metal-air batteries.Although Fe-N-C single atom catalysts(SACs) have been hailed as the most promising candidate due to the optimal binding strength of ORR intermediates on the Fe-N_(4) sites,they suffer from serious mass transport limitations as microporous templates/substrates,i.e.,zeolitic imidazolate frameworks(ZIFs),are usually employed to host the active sites.Motivated by this challenge,we herein develop a hydrogen-bonded organic framework(HOF)-assisted pyrolysis strategy to construct hierarchical micro/mesoporous carbon nanoplates for the deposition of atomically dispersed Fe-N_(4) sites.Such a design is accomplished by employing HOF nanoplates assembled from 2-aminoterephthalic acid(NH_(2)-BDC) and p-phenylenediamine(PDA) as both soft templates and C,N precursors.Benefitting from the structural merits inherited from HOF templates,the optimized catalyst(denoted as Fe-N-C SAC-950) displays outstanding ORR activity with a high half-wave potential of 0.895 V(vs.reversible hydrogen electrode(RHE)) and a small overpotential of 356 mV at 10 mA cm^(-2) for the oxygen evolution reaction(OER).More excitingly,its application potential is further verified by delivering superb rechargeability and cycling stability with a nearly unfading charge-discharge gap of 0.72 V after 160 h.Molecular dynamics(MD) simulations reveal that micro/mesoporous structure is conducive to the rapid mass transfer of O_(2),thus enhancing the ORR performance.In situ Raman results further indicate that the conversion of O_(2) to~*O_(2)-the rate-determining step(RDS) for Fe-N-C SAC-950.This work will provide a versatile strategy to construct single atom catalysts with desirable catalytic properties.

CARD11 serves as a therapeutic biomarker for the drug therapies of ccRCC

Background:The incidence of clear cell renal cell carcinoma(ccRCC)is globally high;however,despite the introduction of innovative drug therapies,there remains a lack of effective biomarkers for evaluating treatment response.Recently,Caspase recruiting domain-containing protein 11(CARD11)has garnered attention due to its significant association with tumor development and the immune system.Methods:The expression of CARD11 mRNA and protein in ccRCC were analyzed by public database and immunohistochemistry.The focus of this study is on the epigenomic modifications of CARD11,its expression of ccRCC immunophenotype,and its correlation with response to immunotherapy and targeted therapy.Furthermore,to investigate the mechanism of this molecule’s influence on different biological behaviors of cells,cell tests in vitro have been conducted to observe the impact of its expression level.Results:CARD11 expression was upregulated which may be mainly modified by body methylation and was correlated with poor prognosis in ccRCC.In the tumor microenvironment of ccRCC,CARD11 expression was positively correlated with increased T lymphocyte infiltration and increased expression of inhibitory immune checkpoints.Moreover,ccRCC patients with high CARD11 expression had a better response to immunotherapy and targeted therapy.The knockdown of CARD11 ultimately suppressed the proliferation,migration,and invasion capabilities of ccRCC cells while simultaneously enhancing tumor cell apoptosis.Conclusion:We identified CARD11 as a novel therapeutic biomarker for immunotherapy and targeted therapy in ccRCC.

面向全寿命周期管理的隧道维养资金分配决策方法

本文以隧道维养资金分配为研究对象,以全寿命管理为切入点,针对隧道维养资金投入问题提出不同的资金分配思路,并且考虑到隧道在维修养护过程中投资成本高,使用时限长和需求变化多等特点,本文利用基于数据包络法和层次分析法的理论构建一种资金分配方案的决策计算模型。为简化计算,采用数据包络法将隧道维养效益问题转化为资源的静态利用率问题进行分析,随后使用层次分析法考虑社会效益和环境效益等指标,将不同的资金方案进行排序选择,得到最优方案。

城市轨道交通TOD开发的地价溢出效应研究——以广州市地铁TOD为例

地铁TOD开发是一种融合地铁交通和城市开发为一体的城市开发模式,对实现城市空间高质量发展具有重要影响。地铁TOD溢出表现在TOD站域内部和站域之间,开展地铁TOD溢出研究对合理制定城市基准地价和构建公共资源开发中的利益补偿机制具有重要参考意义。本文提出了测度TOD开发溢出效应的方法和策略,并以广州220个地铁TOD站域为样本,将TOD开发5D原则转化的17个量化指标作为影响地价的潜在因素,构建了包含TOD开发溢出效应的回归模型,验证了其开发对不同类型用地地价的影响和溢出作用。研究结果显示:①将TOD开发的5D原则转化为可计算变量,为地价的影响因子提供了理论基础;②通过空间回归模型捕捉地铁TOD站域之间的地价溢出,同时向空间回归模型引入虚拟变量捕捉地铁TOD站域内的地价溢出是一种测度地铁TOD溢出的有效途径;③以地铁TOD站域为空间单元的广州市地价空间分布在市域和站域2个尺度上均表现为圈层结构和遵循距离衰减规律,但是分类型用地地价的空间分布模式在不同类型的TOD站域存在差异;④广州市从2010—2019年,除了办公地价在TOD站域内不存在溢出效应外,商业地价、住宅地价和工业地价均存在TOD站域之间和站域内的正溢出效应。相对于2010年,2019年TOD站域之间的溢出弱化,站域内部的溢出增强。基于研究结论,提出了规划TOD廊道;根据TOD站域功能确定各类型土地的合理比例;优先开发近地铁站点的商业和住宅用地;考虑站域开发溢出效应,建立TOD站域开发的利益补偿机制等政策建议。

Effects of the Fhb1 gene on Fusarium head blight resistance and agronomic traits of winter wheat

The gene Fhb1 has been used in many countries to improve wheat Fusarium head blight(FHB) resistance. To make better use of this gene in the Yellow-Huai River Valleys Winter Wheat Zone(YHWZ), the most important wheat-producing region of China, it is desirable to elucidate its effects on FHB resistance and agronomic traits in different genetic backgrounds. Based on a diagnostic marker for Fhb1, six BC2 populations were developed by crossing dwarf-male-sterile(DMS)-Zhoumai 16 to three Fhb1 donors(Ningmai 9, Ningmai 13, and Jianyang 84) and backcrossing to Zhoumai 16 and Zhoumai16’s derivative cultivars(Lunxuan 136 and Lunxuan 13) using marker-assisted backcross breeding. The progenies were assessed for FHB resistance and major agronomic traits.The Fhb1 alleles were identified using the gene-specific molecular marker. The plants with the Fhb1-resistant genotype(Fhb1-R) in these populations showed significantly fewer infected spikelets than those with the Fhb1-susceptible genotype(Fhb1-S). When Lunxuan 136 was used as the recurrent parent, Fhb1-R plants showed significantly fewer infected spikelets per spike than Fhb1-R plants produced using Lunxuan 13 as the recurrent parent, indicating that the genetic backgrounds of Fhb1 influence the expression of FHB resistance. Fhb1-R plants from the DMS-Zhoumai 16/Ningmai 9//Zhoumai 16/3/Lunxuan 136 population showed the highest FHB resistance among the six populations and a significantly higher level of FHB resistance than the moderately susceptible control Huaimai 20. No significant phenotypic differences between Fhb1-R and Fhb1-S plants were observed for the eight agronomic traits investigated. These results suggest that it is feasible to improve FHB resistance of winter wheat withoutreducing yield potential by introgressing Fhb1 resistance allele into FHB-susceptible cultivars in the YHWZ.

Small intestinal hemolymphangioma treated with enteroscopic injection sclerotherapy: A case report and review of literature

BACKGROUND Hemolymphangiomas are rare malformations composed of both lymphatic and vascular vessels and are located in the pancreas,spleen,mediastinum,etc.Small intestinal hemolymphangioma is extremely rare and often presents as obscure gastrointestinal bleeding.It is rarely diagnosed correctly before the operation.Endoscopic injection sclerotherapy is usually used as a management of bleeding in esophageal varices and was occasionally reported as a treatment of vascular malformation.The treatment of small intestinal hemolymphangioma with enteroscopic injection sclerotherapy has not been reported.CASE SUMMARY A 42-year-old male complained of recurrent episodes of melena and dizziness,fatigue and reduced exercise capacity for more than 2 mo.Gastroduodenoscopy and blood test revealed a gastric ulcer and anemia.Treatment with oral protonpump inhibitors and iron did not improve symptoms.We then performed a capsule endoscopy and anterograde balloon-assisted enteroscopy and revealed a hemolymphangioma.Considering it is a benign tumor without malignant potential,we performed enteroscopic injection sclerotherapy.He was discharged 4 days later.At follow-up 3 mo later,the melena disappeared.Balloon-assisted enteroscopy revealed an atrophied tumor atrophied and no bleeding.Argon plasma coagulation was applied to the surface of the hemolymphangioma to accelerated healing.When he returned for follow-up 1 year later,anemia was resolved and the tumor had been cured.CONCLUSION Balloon-assisted enteroscopy and capsule endoscopy are effective methods for diagnosis of hemolymphangioma.Enteroscopic injection sclerotherapy is an effective treatment.

Novel germline mutations in FLCN geneidentiied in two Chinese patients with Birt–Hogg–Dubésyndrome

Birt–Hogg–Dubé(BHD) syndrome, a hereditary renal cancer syndrome caused by mutations in the folliculin(FLCN) gene, is characterized by the presence of ibrofolliculomas, pulmonary cysts, spontaneous pneumothorax, and renal cell carcinoma(RCC). Few BHD syndrome cases have been reported in Asian countries, and cutaneous presentations are relatively rare in Asian patients. Asian BHD patients may be misdiagnosed due to their atypical manifestations. Here, we report two Chinese BHD patients with novel FLCN mutations(c.946-947 del AG in exon 9 and c.770-772 del CCT in exon 7). Both of them had RCC and spontaneous pneumothorax without ibrofolliculomas. In patients with RCC and pulmonary cysts but without cutaneous lesions, screening for mutations in the FLCN gene should be performed, especially for those with a family history of RCC or pulmonary cysts(pneumothorax).

Variation in allelic frequencies at loci associated with kernel weight and their effects on kernel weight-related traits in winter wheat

Knowledge of allelic frequencies at loci associated with kernel weight and effects on kernel weight-related traits is crucial for yield improvement in wheat. Kernel weight-related traits were evaluated in 200 Chinese winter wheat cultivars(lines) grown at the Xinxiang Experimental Station, Chinese Academy of Agricultural Sciences, Xinxiang in Henan Province, for three consecutive years from 2014 to 2016. Alleles associated with kernel weight at nine loci, TaCKX6-D1, TaCwi-A1, TaCWI-4A, TaGS1a, TaGS5-A1, TaGS3-3A, TaGW2-6A, TaSus2-2B, and TaTGW6-A1, were determined for all cultivars(lines). ANOVA showed that genotypes, years and their interactions had significant effects on thousand-kernel weight(TKW), kernel length(KL) and kernel width(KW). The overall mean frequencies of alleles conferring high and low TKW at the nine loci were 65.9% and 33.4%, with the ranges of 37.0%–85.0% and 13.5%–63.0% for single loci. The frequencies of high-TKW alleles were over 50.0% at eight of the loci. Genotypes at each locus with the high-TKW allele had higher TKW than those with the low-TKW allele. The high-TKW allele Hap-H at the TaSus2-2B locus can be preferably used to increase grain yield due to its high TKW(49.32 g). A total of 18 main allelic combinations(ACs) at nine loci were detected. Three ACs(AC1–AC3) had significantly higher TKW than AC6 with high-TKW alleles at all nine loci even though they contained some low-TKW alleles. This indicated that other loci controlling kernel weight were present in the high-TKW cultivars. This work provides important information for parental selection and marker-assisted selection for breeding.

YM155 inhibits retinal pigment epithelium cell survival through EGFR/MAPK signaling pathway

AIM:To investigate YM155’s effect on retinal pigment epithelium(RPE)cells’viability and the potential regulatory mechanisms.METHODS:Human immortalized RPE cell lines(ARPE-19 cell line)were processed with YM155 and epidermal growth factor(EGF).ARPE-19 cell viability was detected by methyl thiazolyl tetrazolium assay,and apoptosis was tested by flow cytometry assay.ARPE-19 cell proliferation was assessed with bromodeoxyuridine tagged incorporation assay,and migration ability was evaluated via a wound-healing assay.Epidermal growth factor receptor(EGFR)/MAPK pathway proteins were tested via immunoblotting.EGFR localization was examined by immunofluorescence assay.RESULTS:YM155 suppressed ARPE-19 cells’viability in a time and concentration-dependent manner.A high dose of YM155 caused a small amount of ARPE-19 cell death.YM155 significantly diminished the ARPE-19 cells’proliferative and migrative capacity.YM155 downregulated total EGFR and phosphorylated external signalregulated protein kinase(ERK),and it up-regulated the phosphorylation of P38 MAPK and c-Jun N-terminal kinase(JNK).YM155 induced endocytosis of EGFR in ARPE-19 cell.YM155 also attenuated EGF-induced ARPE-19 cells’proliferative and migrative capacity.Moreover,YM155 significantly decreased the expression of phosphorylated EGFR and ERK after treated by EGF.CONCLUSION:YM155 inhibits RPE cell survival,the cell proliferative and migrative capacity,and it effectuates a small amount of cell death through the EGFR/MAPK signaling pathway.YM155 might,therefore,be an agent to prevent and treat abnormal RPE cell survival in proliferative vitreoretinopathy.

Recent and imminent calving events do little to impair Amery ice shelf’s stability

Accounting for about half of mass loss in Antarctic,glacier calving is an important ablation process for the ice sheet(Liu et al.,2015).Thanks to the revolutionized era of satellite remote sensing,the 21st century witnessed dozens of prominent calving events.However,calving could occur as a natural behavior of the glacier to maintain itself in a steady state,rather than forced by external environment factors.

Effectiveness of surgical resection for complicated liver cancer and its influencing factors: A retrospective study

BACKGROUND Surgical resection is the preferred method for patients with complex liver cancer.But the tumor is in a special position, the surgery is highly risky, postoperative complications can easily occur, and the prognosis is not ideal.AIM To investigate the effectiveness of surgical resection for complex liver cancer and its influencing factors.METHODS Fifty-seven patients who had complicated liver cancer and underwent surgical resection at our hospital from August 2015 to August 2016 were enrolled in this study. All patients were followed for three years, and their postoperative complications, survival, and factors that impacted their survival were analyzed.RESULTS The total incidence of postoperative complications was 45.61%, and the incidence of pleural effusion was the highest at 28.07%. There were no correlations between the 2-year and 3-year survival rates and sex, age, and Hbs Ag of the patients(P >0.05). In terms of pathological parameters, the 2-year and 3-year survival rates were significantly different according to the presence of a tumor capsule, degree of liver cirrhosis, satellite or focal lesions, hepatic vein thrombosis, portal vein tumor thrombus, and intraoperative blood loss(P < 0.05).CONCLUSIONThe effectiveness of surgical resection for complex hepatocellular carcinoma may be affected by factors such as the presence of a tumor capsule, cirrhosis degree,satellite or focal lesions, hepatic vein embolization, portal vein tumor thrombus,and intraoperative blood loss. Therefore, these factors should be controlled and prevented during surgery to help improve patient survival after surgery.

Effect of interfacial stiffness on the stretchability of metal/elastomer bilayers under in-plane biaxial tension

Flexible electronic devices are often subjected to large and repeated deformation,so that their functional components such as metal interconnects need to sustain strains up to tens of percent,which is far beyond the intrinsic deformability of metal materials(~1%).To meet the stringent requirements of flexible electronics,metal/elastomer bilayers,a stretchable structure that consists of a metal film adhered to a stretchable elastomer substrate,have been developed to improve the stretch capability of metal interconnects.Previous studies have predicted that the metal/elastomer bilayers are much more stretchable than freestanding metal films.However,these investigations usually assume perfect bonding between the metal and elastomer layers.In this work,the effect of the metal/elastomer interface with a finite interfacial stiffness on the stretchability of bilayer structures is analyzed.The results show that the assumption of perfect interface(with infinite interfacial stiffness)may lead to an overestimation of the stretchability of bilayer structures.It is also demonstrated that increased adhesion between the metal and elastomer layers can enhance the stretchability of the metal layer.

Geometrical Design and Hydraulic Feasibility of Inner-Reinforced Girders in Hydropower Bifurcations

Inner-reinforced girders, also known as ribs, are widely used in hydropower bifurcations. However, while they strengthen structures, they also cause energy loss. This work aims to develop an appropriate geometry form for ribs that can diminish head loss in hydropower bifurcations. The term rib/breadth ratio (RBR) is defined to describe the geometrical form of ribs. An investigation is conducted to study the flow and performance characteristics of bifurcations with ribs using computational fluid dynamics. The dependence of the head loss coefficient on the RBR is given in six working conditions. Results show that the ribs change the local flow patterns and slightly increase the water head loss in some cases. In other cases, however, the ribs make the flow smooth. An appropriate RBR is the key to improve the flow patterns in hydropower bifurcations. The head loss varies with the RBR and reaches the minimum when the RBR is 0.3. © 2017, Tianjin University and Springer-Verlag GmbH Germany.