学术人才流动可以提高科研产出吗?

学术人才的流动一直是学术共同体推动科研生产的重要议题,但是其流动是否能够真正提高科研产出却仍然存在争议。以教育部长江学者特聘教授为样本,使用计量模型检验流动对学者科研产出的影响作用。回归结果表明,流动能够推动学者科研产出的提升,特别是对学者英文发表有着显著的促进效应。以匹配激励效应和知识重组效应展开回归结果的解释和讨论,结合中国高等教育和科技创新国际化发展趋势,匹配激励效应被认为是其中的主要作用机制。政府应完善学术人才流动的制度环境,探索建立对人才流出高校的利益补偿机制,以推动学术人才在学术共同体内的有序流动,同时也要更加注重和引导流动知识重组效应的发挥。

过渡态理论对Arrhenius公式的诠释——以硝酸异丙酯与自由基反应为例

大学物理化学教学中,Arrhenius公式阐述了反应的速率常数与温度及活化能的关系,但是,单纯从公式的表达式进行讲解,难免枯燥乏味,不利于学生理解和掌握。本文以硝酸异丙酯与Cl原子、OH和NO_(3)自由基反应为例,基于反应的势能面,用过渡态理论计算不同温度下反应的速率常数,直观形象地分析了在不同反应能垒时,反应速率常数随温度的变化情况,以期帮助学生从本质上理解Arrhenius公式,拓宽他们的知识面,培养其科学探究的意识和能力。

尼可地尔对急性冠脉综合征患者PCI介入治疗后炎性相关指标的影响

目的探讨急性冠脉综合征(acute coronary syndrome,ACS)患者经皮冠状动脉介入治疗(percutaneous coronary intervention,PCI)后采用尼可地尔治疗后对炎性相关指标的影响,评估其对血管内皮功能的影响。方法将2022年8月至2023年1月于大连医科大学附属第二医院心血管内科行PCI治疗的66例ACS患者作为研究样本,按照完全随机设计法分成对照组和试验组,每组33例。对照组行常规疗法,试验组用尼可地尔治疗。比较2组患者血清中的炎性指标、同型半胱氨酸(hcy)和不良反应情况。结果尼可地尔治疗后,对照组术后炎性相关因子水平高于试验组,差异具有统计学意义(P<0.05);尼可地尔治疗后Hcy水平低于对照组,差异具有统计学意义(P<0.05);试验组不良反应率高于对照组,差异无统计学意义(P>0.05)。结论尼可地尔应用在老年ACS患者PCI术后疗效确切,能优化血管相关炎性指标,降低同型半胱氨酸水平改善冠状动脉血管内皮功能,适合进一步推广。

Decade Milestone Advancement of Defect-Engineered g-C_(3)N_(4) for Solar Catalytic Applications

Over the past decade, graphitic carbon nitride(g-C_(3)N_(4)) has emerged as a universal photocatalyst toward various sustainable carbo-neutral technologies. Despite solar applications discrepancy, g-C_(3)N_(4) is still confronted with a general fatal issue of insufficient supply of thermodynamically active photocarriers due to its inferior solar harvesting ability and sluggish charge transfer dynamics. Fortunately, this could be significantly alleviated by the “all-in-one” defect engineering strategy, which enables a simultaneous amelioration of both textural uniqueness and intrinsic electronic band structures. To this end, we have summarized an unprecedently comprehensive discussion on defect controls including the vacancy/non-metallic dopant creation with optimized electronic band structure and electronic density, metallic doping with ultraactive coordinated environment(M–N_(x), M–C_(2)N_(2), M–O bonding), functional group grafting with optimized band structure, and promoted crystallinity with extended conjugation π system with weakened interlayered van der Waals interaction. Among them, the defect states induced by various defect types such as N vacancy, P/S/halogen dopants, and cyano group in boosting solar harvesting and accelerating photocarrier transfer have also been emphasized. More importantly, the shallow defect traps identified by femtosecond transient absorption spectra(fs-TAS) have also been highlighted. It is believed that this review would pave the way for future readers with a unique insight into a more precise defective g-C_(3)N_(4) “customization”, motivating more profound thinking and flourishing research outputs on g-C_(3)N_(4)-based photocatalysis.

Forebrain excitatory neuron-specific loss of Brpf1 attenuates excitatory synaptic transmission and impairs spatial and fear memory

Bromodomain and plant homeodomain(PHD)finger containing protein 1(Brpf1)is an activator and scaffold protein of a multiunit complex that includes other components involving lysine acetyltransferase(KAT)6A/6B/7.Brpf1,KAT6A,and KAT6B mutations were identified as the causal genes of neurodevelopmental disorders leading to intellectual disability.Our previous work revealed strong and specific expression of Brpf1 in both the postnatal and adult forebrain,especially the hippocampus,which has essential roles in learning and memory.Here,we hypothesized that Brpf1 plays critical roles in the function of forebrain excitatory neurons,and that its deficiency leads to learning and memory deficits.To test this,we knocked out Brpf1 in forebrain excitatory neurons using CaMKIIa-Cre.We found that Brpf1 deficiency reduced the frequency of miniature excitatory postsynaptic currents and downregulated the expression of genes Pcdhgb1,Slc16a7,Robo3,and Rho,which are related to neural development,synapse function,and memory,thereby damaging spatial and fear memory in mice.These findings help explain the mechanisms of intellectual impairment in patients with BRPF1 mutation.

A Stable Open-Shell Conjugated Diradical Polymer with Ultra-High Photothermal Conversion Efficiency for NIR-Ⅱ Photo-Immunotherapy of Metastatic Tumor

Massive efforts have been concentrated on the advance of eminent near-infrared(NIR) photothermal materials(PTMs) in the NIR-Ⅱ window(1000–1700 nm), especially organic PTMs because of their intrinsic biological safety compared with inorganic PTMs. However, so far, only a few NIR-Ⅱresponsive organic PTMs was explored, and their photothermal conversion efficiencies(PCEs) still remain relatively low. Herein, donor–acceptor conjugated diradical polymers with open-shell characteristics are explored for synergistically photothermal immunotherapy of metastatic tumors in the NIR-Ⅱ window. By employing side-chain regulation, the conjugated diradical polymer TTB-2 with obvious NIR-Ⅱ absorption was developed, and its nanoparticles realize a record-breaking PCE of 87.7% upon NIR-Ⅱ light illustration. In vitro and in vivo experiments demonstrate that TTB-2 nanoparticles show good tumor photoablation with navigation of photoacoustic imaging in the NIR-Ⅱ window, without any side-effect. Moreover, by combining with PD-1 antibody,the pulmonary metastasis of breast cancer is high-effectively prevented by the efficient photo-immunity effect. Thus, this study explores superior PTMs for cancer metastasis theranostics in the NIR-Ⅱ window, offering a new horizon in developing radical-characteristic NIR-Ⅱ photothermal materials.

凝血指标预测立体定向治疗NSCLC脑转移疗效

目的:分析凝血指标对非小细胞肺癌(non-small cell lung cancer,NSCLC)脑转移患者立体定向放射外科(stereotactic ra-dio surgery,SRS)治疗预后的预测价值。方法:回顾性收集2015年10月至2018年9月在天津市环湖医院确诊为NSCLC脑转移并行SRS治疗的512例患者临床资料,分析总体生存(overall survival,OS)率与无进展生存(progression-free survival,PFS)率,运用Cox多因素分析影响预后相关因素,并基于Cox多因素分析绘制工作特征(receiver operating characteristic,ROC)曲线,运用曲线下面积(area under the ROC curve,AUC)分析凝血指标对NSCLC脑转移行SRS治疗患者预后的预测价值。结果:1、2、3、4年的PFS分别为79.9%、69.9%、56.6%、43.2%,OS分别为93.4%、83.2%、69.9%、57.6%。吸烟、纤维蛋白原(fibrinogen,Fib)<3.22 g/L、凝血酶原时间(prothrombin time,PT)<11.69 s、D-二聚体(D-dimer,D-D)<0.51μg/L与较长的PFS率相关(P<0.05);活化部分凝血活酶时间(activated partial thromboplastin time,APTT)<21.05 s、Fib<3.22 g/L、D-D<0.51μg/mL与较长的OS率相关(P<0.05)。吸烟、Fib<3.22 g/L、D-D<0.51μg/mL与较长的PFS率显著相关(P<0.05);Fib<3.22 g/L、D-D<0.51μg/mL与较长的OS率显著相关(P<0.05)。Fib与D-D联合检测预测NSCLC脑转移患者SRS治疗预后的AUC显著高于Fib与D-D单独检测(P<0.05)。结论:凝血指标与SRS治疗的NSCLC脑转移患者预后有一定相关性,Fib与D-D为患者预后独立危险因素,可用于评估其预后,两组指标联合评估价值可能更优,具有进一步深入研究的价值。

Intrahepatic portal venous systems in adult patients with cavernous transformation of portal vein: Imaging features and a new classification

Background: Cavernous transformation of the portal vein(CTPV) due to portal vein obstruction is a rare vascular anomaly defined as the formation of multiple collateral vessels in the hepatic hilum. This study aimed to investigate the imaging features of intrahepatic portal vein in adult patients with CTPV and establish the relationship between the manifestations of intrahepatic portal vein and the progression of CTPV. Methods: We retrospectively analyzed 14 CTPV patients in Beijing Tsinghua Changgung Hospital. All patients underwent both direct portal venography(DPV) and computed tomography angiography(CTA) to reveal the manifestations of the portal venous system. The vessels measured included the left portal vein(LPV), right portal vein(RPV), main portal vein(MPV) and the portal vein bifurcation(PVB). Results: Nine males and 5 females, with a median age of 40.5 years, were included in the study. No significant difference was found in the diameters of the LPV or RPV measured by DPV and CTA. The visualization in terms of LPV, RPV and PVB measured by DPV was higher than that by CTA. There was a significant association between LPV/RPV and PVB/MPV in term of visibility revealed with DPV( P = 0.01), while this association was not observed with CTA. According to the imaging features of the portal vein measured by DPV, CTPV was classified into three categories to facilitate the diagnosis and treatment. Conclusions: DPV was more accurate than CTA for revealing the course of the intrahepatic portal vein in patients with CTPV. The classification of CTPV, that originated from the imaging features of the portal vein revealed by DPV, may provide a new perspective for the diagnosis and treatment of CTPV.

Knee osteoarthritis:A review of animal models and intervention of traditional Chinese medicine

Background:Knee osteoarthritis(KOA)characterized by degeneration of knee cartilage and subsequent bone hyperplasia is a prevalent joint condition primarily affecting aging adults.The pathophysiology of KOA remains poorly understood,as it involves complex mechanisms that result in the same outcome.Consequently,researchers are interested in studying KOA and require appropriate animal models for basic research.Chinese herbal compounds,which consist of multiple herbs with diverse pharmacological properties,possess characteristics such as multicomponent,multipathway,and multitarget effects.The potential benefits in the treatment of KOA continue to attract attention.Purpose:This study aims to provide a comprehensive overview of the advantages,limitations,and specific considerations in selecting different species and methods for KOA animal models.This will help researchers make informed decisions when choosing an animal model.Methods:Online academic databases(e.g.,PubMed,Google Scholar,Web of Science,and CNKI)were searched using the search terms“knee osteoarthritis,”“animal models,”“traditional Chinese medicine,”and their combinations,primarily including KOA studies published from 2010 to 2023.Results:Based on literature retrieval,this review provides a comprehensive overview of the methods of establishing KOA animal models;introduces the current status of advantages and disadvantages of various animal models,including mice,rats,rabbits,dogs,and sheep/goats;and presents the current status of methods used to establish KOA animal models.Conclusion:This study provides a review of the animal models used in recent KOA research,discusses the common modeling methods,and emphasizes the role of traditional Chinese medicine compounds in the treatment of KOA.

Nursing effect of narrative nursing intervention on postoperative patients with severe lung cancer

BACKGROUND Lung cancer is a common disease with high mortality,and psychological support is very important in the diagnosis and treatment of postoperative patients with cancer pain.AIM To explore the application effect of the narrative nursing method in postoperative lung cancer patients in the intensive care unit.METHODS A total of 120 patients diagnosed with lung cancer and experiencing cancer-related pain were randomly allocated into two groups:an observation group and a control group,each consisting of 60 cases.The control group was given routine analgesic and psychological care,while the research group applied the five-step narrative nursing method based on routine care,comparing the visual analogue scale scores,sleep status,anxiety and depression status,and quality of life of the two groups of patients before and after the intervention.RESULTS The pain scores,anxiety scores,and depression scores of the study group were lower than those of the control group after the intervention using the narrative nursing method,and the difference was statistically significant(P<0.05).CONCLUSION Using narrative nursing methods to intervene in patients with lung cancer combined with cancerous pain can help patients to correctly recognize their disease,adjust their mentality,establish confidence,alleviate patients'subjective pain feelings,and improve their adverse emotions.

Coca-Cola consumption vs fragmentation in the management of patients with phytobezoars:A prospective randomized controlled trial

BACKGROUND Gastric phytobezoars(GPBs)are very common in northern China.Combined therapy involving carbonated beverage consumption and endoscopic lithotripsy has been shown to be effective and safe.Existing studies on this subject are often case reports highlighting the successful dissolution of phytobezoars through Coca-Cola consumption.Consequently,large-scale prospective investigations in this domain remain scarce.Therefore,we conducted a randomized controlled trial to examine the effects of Coca-Cola consumption on GPBs.AIM To evaluate the impact of Coca-Cola on GPBs,including the dissolution rate,medical expenses,ulcer rate,and operation time.METHODS A total of 160 consecutive patients diagnosed with GPBs were allocated into two groups(a control group and an intervention group)through computer-generated randomization.Patients in the intervention group received a Coca-Cola-based regimen(Coca-Cola 2000-4000 mL per day for 7 d),while those in the control group underwent emergency fragmentation.RESULTS Complete dissolution of GPBs was achieved in 100% of the patients in the intervention group.The disparity in expenses between the control group and intervention group(t=25.791,P=0.000)was statistically significant,and the difference in gastric ulcer occurrence between the control group and intervention group(χ^(2)=6.181,P=0.013)was also statistically significant.CONCLUSION Timely ingestion of Coca-Cola yields significant benefits,including a complete dissolution rate of 100%,a low incidence of gastric ulcers,no need for fragmentation and reduced expenses.

Single-cell RNA sequencing analysis of the retina under acute high intraocular pressure

High intraocular pressure causes retinal ganglion cell injury in primary and secondary glaucoma diseases,yet the molecular landscape characteristics of retinal cells under high intraocular pressure remain unknown.Rat models of acute hypertension ocular pressure were established by injection of cross-linked hyaluronic acid hydrogel(Healaflow■).Single-cell RNA sequencing was then used to describe the cellular composition and molecular profile of the retina following high intraocular pressure.Our results identified a total of 12 cell types,namely retinal pigment epithelial cells,rod-photoreceptor cells,bipolar cells,Müller cells,microglia,cone-photoreceptor cells,retinal ganglion cells,endothelial cells,retinal progenitor cells,oligodendrocytes,pericytes,and fibroblasts.The single-cell RNA sequencing analysis of the retina under acute high intraocular pressure revealed obvious changes in the proportions of various retinal cells,with ganglion cells decreased by 23%.Hematoxylin and eosin staining and TUNEL staining confirmed the damage to retinal ganglion cells under high intraocular pressure.We extracted data from retinal ganglion cells and analyzed the retinal ganglion cell cluster with the most distinct expression.We found upregulation of the B3gat2 gene,which is associated with neuronal migration and adhesion,and downregulation of the Tsc22d gene,which participates in inhibition of inflammation.This study is the first to reveal molecular changes and intercellular interactions in the retina under high intraocular pressure.These data contribute to understanding of the molecular mechanism of retinal injury induced by high intraocular pressure and will benefit the development of novel therapies.

T cell interactions with microglia in immune-inflammatory processes of ischemic stroke

The primary mechanism of secondary injury after cerebral ischemia may be the brain inflammation that emerges after an ischemic stroke,which promotes neuronal death and inhibits nerve tissue regeneration.As the first immune cells to be activated after an ischemic stroke,microglia play an important immunomodulatory role in the progression of the condition.After an ischemic stroke,peripheral blood immune cells(mainly T cells)are recruited to the central nervous system by chemokines secreted by immune cells in the brain,where they interact with central nervous system cells(mainly microglia)to trigger a secondary neuroimmune response.This review summarizes the interactions between T cells and microglia in the immune-inflammatory processes of ischemic stroke.We found that,during ischemic stroke,T cells and microglia demonstrate a more pronounced synergistic effect.Th1,Th17,and M1 microglia can co-secrete proinflammatory factors,such as interferon-γ,tumor necrosis factor-α,and interleukin-1β,to promote neuroinflammation and exacerbate brain injury.Th2,Treg,and M2 microglia jointly secrete anti-inflammatory factors,such as interleukin-4,interleukin-10,and transforming growth factor-β,to inhibit the progression of neuroinflammation,as well as growth factors such as brain-derived neurotrophic factor to promote nerve regeneration and repair brain injury.Immune interactions between microglia and T cells influence the direction of the subsequent neuroinflammation,which in turn determines the prognosis of ischemic stroke patients.Clinical trials have been conducted on the ways to modulate the interactions between T cells and microglia toward anti-inflammatory communication using the immunosuppressant fingolimod or overdosing with Treg cells to promote neural tissue repair and reduce the damage caused by ischemic stroke.However,such studies have been relatively infrequent,and clinical experience is still insufficient.In summary,in ischemic stroke,T cell subsets and activated microglia act synergistically to regulate inflammatory progression,mainly by secreting inflammatory factors.In the future,a key research direction for ischemic stroke treatment could be rooted in the enhancement of anti-inflammatory factor secretion by promoting the generation of Th2 and Treg cells,along with the activation of M2-type microglia.These approaches may alleviate neuroinflammation and facilitate the repair of neural tissues.

Effectiveness of a theory-based tailored mHealth physical activity intervention for women undergoing chemotherapy for breast cancer:A quasi-experimental study

Objectives:This study aimed to explore the effectiveness of the theory-based tailored mHealth physical activity(PA)intervention among patients with breast cancer undergoing chemotherapy.Methods:A quasi-experimental study design was adopted.A total of 60 breast cancer patients were selected from two tertiary hospitals in Shanghai and Hangzhou City from September 2019 to August 2021.According to the admission order,30 patients werefirst included in the control group,followed by 30 patients in the intervention group.A smartphone application(app)named“Breast Care”was developed based on social cognitive theory,self-efficacy theory,and the theory of planned behavior.The app integrated various functions,including information browsing,PA monitoring and feedback,symptom reporting,and social interaction.Patients in the intervention group received three months of personalized online PA guidance in addition to routine care.The control group received routine care.Baseline and post-intervention investigations after three months were conducted in two groups using the Short Form of International Physical Activity Questionnaire,the Hospital Anxiety and Depression Scale,and the Functional Assessment of Cancer TherapydBreast cancer.Results:After three months of intervention,compared to the control group,breast cancer patients in the intervention group showed significant improvements in walking,moderate PA,and overall PA(P<0.05).Compared to the baseline data,breast cancer patients in the intervention group had significant improvements in walking and overall PA after three months(P<0.05),whereas the control group experienced significant declines in walking,moderate PA,and overall PA after three months(P<0.05).There were statistically differences between the two groups in scores for anxiety,overall quality of life,and its dimensions,such as physical well-being,emotional well-being,and additional breast cancer well-being(P<0.05).Conclusions:The theory-based tailored mHealth PA intervention has demonstrated a positive impact on promoting PA behavior change and emotional management among breast cancer patients.The‘Breast Care’app integrated various practical behavior change strategies,offering valuable guidance for personalized remote rehabilitation support for cancer patients.

Micro-aluminum powder with bi-or tri-component alloy coating as a promising catalyst:Boosting pyrolysis and combustion of ammonium perchlorate

A novel design of micro-aluminum(μAl)powder coated with bi-/tri-component alloy layer,such as:Ni-P and Ni-P-Cu(namely,Al@Ni-P,Al@Ni-P-Cu,respectively),as combustion catalysts,were introduced to release its huge energy inside Al-core and promote rapid pyrolysis of ammonium perchlorate(AP)at a lower temperature in aluminized propellants.The microstructure of Al@Ni-P-Cu demonstrates that a three-layer Ni-P-Cu shell,with the thickness of~100 nm,is uniformly supported byμAl carrier(fuel unit),which has an amorphous surface with a thickness of~2.3 nm(catalytic unit).The peak temperature of AP with the addition of Al@Ni-P-Cu(3.5%)could significantly drop to 316.2℃ at high-temperature thermal decomposition,reduced by 124.3℃,in comparison to that of pure AP with 440.5℃.It illustrated that the introduction of Al@Ni-P-Cu could weaken or even eliminate the obstacle of AP pyrolysis due to its reduction of activation energy with 118.28 kJ/mol.The laser ignition results showed that the ignition delay time of Al@Ni-P-Cu/AP mixture with 78 ms in air is shorter than that of Al@Ni-P/AP(118 ms),decreased by 33.90%.Those astonishing breakthroughs were attributed to the synergistic effects of adequate active sites on amorphous surface and oxidation exothermic reactions(7597.7 J/g)of Al@Ni-P-Cu,resulting in accelerated mass and/or heat transfer rate to catalyze AP pyrolysis and combustion.Moreover,it is believed to provide an alternative Al-based combustion catalyst for propellant designer,to promote the development the propellants toward a higher energy.

Tissue optical clearing enhances efficacy of vascular targeted photodynamic therapy of mouse dorsal skin

Vascular-targeted photodynamic therapy(V-PDT)is an effective treatment for port wine stains(PWS).However,repeated treatment is usually needed to achieve optimal treatment outcomes,possibly due to the limited treatment light penetration depth in the PWS lesion.The optical clearing technique can increase light penetration in depth by reducing light scattering.This study aimed to investigate the V-PDT in combination with an optical clearing agent(OCA)for the therapeutic enhancement of V-PDT in the rodent skinfold window chamber model.Vascular responses were closely monitored with laser speckle contrast imaging(LSCI),optical coherence tomography angiography,and stereo microscope before,during,and after the treatment.We further quantitatively demonstrated the effects of V-PDT in combination with OCA on the blood flow and blood vessel size of skin microvasculature.The combination of OCA and V-PDT resulted in significant vascular damage,including vasoconstriction and the reduction of blood flow.Our results indicate the promising potential of OCA for enhancing V-PDT for treating vascular-related diseases,including PWS.

Origin and evolution of a new tetraploid mangrove species in an intertidal zone

Polyploidy is a major factor in the evolution of plants,yet we know little about the origin and evolution of polyploidy in intertidal species.This study aimed to identify the evolutionary transitions in three truemangrove species of the genus Acanthus distributed in the Indo-West Pacific region.For this purpose,we took an integrative approach that combined data on morphology,cytology,climatic niche,phylogeny,and biogeography of 493 samples from 42 geographic sites.Our results show that the Acanthus ilicifolius lineage distributed east of the Thai-Malay Peninsula possesses a tetraploid karyotype,which is morphologically distinct from that of the lineage on the west side.The haplotype networks and phylogenetic trees for the chloroplast genome and eight nuclear genes reveal that the tetraploid species has two sub-genomes,one each from A.ilicifolius and A.ebracteatus,the paternal and maternal parents,respectively.Population structure analysis also supports the hybrid speciation history of the new tetraploid species.The two sub-genomes of the tetraploid species diverged from their diploid progenitors during the Pleistocene.Environmental niche models revealed that the tetraploid species not only occupied the near-entire niche space of the diploids,but also expanded into novel environments.Our findings suggest that A.ilicifolius species distributed on the east side of the Thai-Malay Peninsula should be regarded as a new species,A.tetraploideus,which originated from hybridization between A.ilicifolius and A.ebracteatus,followed by chromosome doubling.This is the first report of a true-mangrove allopolyploid species that can reproduce sexually and clonally reproduction,which explains the long-term adaptive potential of the species.

Flexibility potential of Cs_(2)BX_(6)(B=Hf,Sn,Pt,Zr,Ti;X=I,Br,Cl)with application in photovoltaic devices and radiation detectors

As interest in double perovskites is growing,especially in applications like photovoltaic devices,understanding their mechanical properties is vital for device durability.Despite extensive exploration of structure and optical properties,research on mechanical aspects is limited.This article builds a vacancyordered double perovskite model,employing first-principles calculations to analyze mechanical,bonding,electronic,and optical properties.Results show Cs_(2)Hfl_(6),Cs_(2)SnBr_(6),Cs_(2)SnI_(6),and Cs_(2)PtBr_(6)have Young's moduli below 13 GPa,indicating flexibility.Geometric parameters explain flexibility variations with the changes of B and X site composition.Bonding characteristic exploration reveals the influence of B and X site electronegativity on mechanical strength.Cs_(2)SnBr_(6)and Cs_(2)PtBr_(6)are suitable for solar cells,while Cs_(2)HfI_(6)and Cs_(2)TiCl_(6)show potential for semi-transparent solar cells.Optical property calculations highlight the high light absorption coefficients of up to 3.5×10^(5) cm^(-1)for Cs_(2)HfI_(6)and Cs_(2)TiCl_(6).Solar cell simulation shows Cs_(2)PtBr_(6)achieves 22.4%of conversion effciency.Cs_(2)ZrCl_(6)holds promise for ionizing radiation detection with its 3.68 eV bandgap and high absorption coefficient.Vacancy-ordered double perovskites offer superior flexibility,providing valuable insights for designing stable and flexible devices.This understanding enhances the development of functional devices based on these perovskites,especially for applications requiring high stability and flexibility.

Understory seedlings of Quercus mongolica survive by phenological escape

Understanding understory seedling regeneration mechanisms is important for the sustainable development of temperate primary forests in the context of increasingly intense climate warming events.The poor regeneration of dominant tree species,however,is one of the biggest challenges it faces at the moment.Especially,the regeneration of the shade-intolerant Quercus mongolica seedling is difficult in primary forests,which contrasts with the extreme abundance of understory seedlings in secondary forests.The mechanism behind the interesting phenomenon is still unknown.This study used in-situ monitoring and nursery-controlled experiment to investigate the survival rate,growth performance,as well as nonstructural carbohydrate (NSC) concentrations and pools of various organ tissues of seedlings for two consecutive years,further analyze the understory light availability and simulate the foliage carbon (C) gain in the secondary and primary forest.Results suggested that seedlings in the secondary forest had greater biomass allocation aboveground,height and specific leaf area (SLA) in summer,which allowed the seedling to survive longer in the canopy closure period.High light availability and positive C gain in early spring and late autumn are key factors affecting the growth and survival of understory seedlings in the secondary forest,whereas seedlings in the primary forest had annual negative carbon gain.Through the growing season,the total NSC concentrations of seedlings gradually decreased,whereas those of seedlings in the secondary forest increased significantly in autumn,and were mainly stored in roots for winter consumption and the following year's summer shade period,which was verified by the nursery-controlled experiment that simulated autumn enhanced light availability improved seedling survival rate and NSC pools.In conclusion,our results revealed the survival trade-off strategies of Quercus mongolica seedlings and highlighted the necessity of high light availability during the spring and autumn phenological periods for shade-intolerant tree seedling recruitment.

Optimization of inter-seasonal nitrogen allocation increases yield and resource-use efficiency in a water-limited wheat-maize cropping system in the North China Plain

Winter wheat–summer maize cropping system in the North China Plain often experiences droughtinduced yield reduction in the wheat season and rainwater and nitrogen(N)fertilizer losses in the maize season.This study aimed to identify an optimal interseasonal water-and N-management strategy to alleviate these losses.Four ratios of allocation of 360 kg N ha^(-1)between the wheat and maize seasons under one-time presowing root-zone irrigation(W0)and additional jointing and anthesis irrigation(W2)in wheat and one irrigation after maize sowing were set as follows:N1(120:240),N2(180:180),N3(240:120)and N4(300:60).The results showed that under W0,the N3 treatment produced the highest annual yield,crop water productivity(WPC),and nitrogen partial factor productivity(PFPN).Increased N allocation in wheat under W0 improved wheat yield without affecting maize yield,as surplus nitrate after wheat harvest was retained in the topsoil layers and available for the subsequent maize.Under W2,annual yield was largest in the N2 treatment.The risk of nitrate leaching increased in W2 when N application rate in wheat exceeded that of the N2 treatment,especially in the wet year.Compared to W2N2,the W0N3 maintained 95.2%grain yield over two years.The WPCwas higher in the W0 treatment than in the W2 treatment.Therefore,following limited total N rate,an appropriate fertilizer N transfer from maize to wheat season had the potential of a“triple win”for high annual yield,WPCand PFPN in a water-limited wheat–maize cropping system.