Review on Metallization Approaches for High-Efficiency Silicon Heterojunction Solar Cells

Crystalline silicon(c-Si)heterojunction(HJT)solar cells are one of the promising technologies for next-generation industrial high-efficiency silicon solar cells,and many efforts in transferring this technology to high-volume manufacturing in the photovoltaic(PV)industry are currently ongoing.Metallization is of vital importance to the PV performance and long-term reliability of HJT solar cells.In this review,we summarize the development status of metallization approaches for highefficiency HJT solar cells.For conventional screen printing technology,to avoid the degradation of the passivation properties of the amorphous silicon layer,a low-temperature-cured(<250℃)paste and process are needed.This process,in turn,leads to high line/contact resistances and high paste costs.To improve the conductivity of electrodes and reduce the metallization cost,multi-busbar,fine-line printing,and low-temperature-cured silver-coated copper pastes have been developed.In addition,several potential metallization technologies for HJT solar cells,such as the Smart Wire Contacting Technology,pattern transfer printing,inkjet/FlexTrailprinting,and copper electroplating,are discussed in detail.B ased on the summary,the potential and challenges of these metallization technologies for HJT solar cells are analyzed.

Clinical significance of Smac expression on non-small cell lung cancers

Objective:The aim of our study was to investigate the clinical significance of Smac(second mitochondria-derived activator of caspase) expression on non-small cell lung cancer(NSCLC).Methods:The expression of Smac was evaluated on RNA and protein level in tumor tissues.The expression of Smac mRNA was examined by RT-PCR in 59 samples of tumor tissues and matched normal lung tissues.The expression of Smac protein was examined by IHC in 213 cancer tissues.Results:The positive rate of Smac mRNA was found in 59.3% of cancer tissues,but only in 30.5% of matched normal tissues(P<0.05).The positive rate of Smac protein was 76.5%.The expression of Smac in stage II disease was significantly higher than that in stage I disease(P=0.001).The survival of patients with Smac overexpression was significantly shorter than those who were negative.Conclusion:Smac might be involved in the progression of NSCLC,the biologic significance of Smac in primary lung cancer needs further study.

Supramolecular assembly of chloroplast NADH dehydrogenase-like complex with photosystem Ⅰfrom Arabidopsis thaliana

Cyclic electron transport/flow(CET/CEF)in chloroplasts is a regulatory process essential for the optimization of plant photosynthetic efficiency.A crucial CEF pathway is catalyzed by a membrane-embedded NADH dehydrogenase-like(NDH)complex that contains at least 29 protein subunits and associates with photosystem I(PSI)to form the NDH-PSI supercomplex.Here,we report the 3.9Åresolution structure of the Arabidopsis thaliana NDH-PSI(AtNDH-PSI)supercomplex.We constructed structural models for 26 AtNDH subunits,among which 11 are unique to chloroplasts and stabilize the core part of the NDH complex.In the supercomplex,one NDH can bind up to two PSI-light-harvesting complex I(PSI-LHCI)complexes at both sides of its membrane arm.Two minor LHCIs,Lhca5 and Lhca6,each present in one PSI-LHCI,interact with NDH and contribute to supercomplex formation and stabilization.Collectively,our study reveals the structural details of the AtNDH-PSI supercomplex assembly and provides a molecular basis for further investigation of the regulatory mechanism of CEF in plants.

OShnscc:a novel user-friendly online survival analysis tool for head and neck squamous cell carcinoma based on RNA expression profiles and long-term survival information

Head and neck squamous cell carcinoma(HNSCC),as the most common type(>90%)of head and neck cancer,includes various epithelial malignancies that arise in the nasal cavity,oral cavity,pharynx,and larynx.In 2020,approximately 878000 new cases and 444000 deaths linked to HNSCC occurred worldwide(Sung et al.,2021).Due to the associated frequent recurrence and metastasis.

Temporal and spatial stability of the EM/PM molecular subtypes in adult diffuse glioma

Detailed characterizations of genomic alterations have not identified subtype-specific vulnerabilities in adult gliomas. Mapping gliomas into developmental programs may uncover new vulnerabilities that are not strictly related to genomic alterations. After identifying conserved gene modules co-expressed with EGFR or PDGFRA (EM or PM), we recently proposed an EM/PM classification scheme for adult gliomas in a histological subtype- and grade-independent manner. By using cohorts of bulk samples, paired primary and recurrent samples, multi-region samples from the same glioma, single-cell RNA-seq samples, and clinical samples, we here demonstrate the temporal and spatial stability of the EM and PM subtypes. The EM and PM subtypes, which progress in a subtype-specific mode, are robustly maintained in paired longitudinal samples. Elevated activities of cell proliferation, genomic instability and microenvironment, rather than subtype switching, mark recurrent gliomas. Within individual gliomas, the EM/PM subtype was preserved across regions and single cells. Malignant cells in the EM and PM gliomas were correlated to neural stem cell and oligodendrocyte progenitor cell compartment, respectively. Thus, while genetic makeup may change during progression and/or within different tumor areas, adult gliomas evolve within a neurodevelopmental framework of the EM and PM molecular subtypes. The dysregulated developmental pathways embedded in these molecular subtypes may contain subtype-specific vulnerabilities.

Architecture of the ATP-driven motor for protein import into chloroplasts

Thousands of nuclear-encoded proteins are transported into chloroplasts through the TOC–TIC translocon that spans the chloroplast envelope membranes.A motor complex pulls the translocated proteins out of the TOC–TIC complex into the chloroplast stroma by hydrolyzing ATP.The Orf2971–FtsHi complex has been suggested to serve as the ATP-hydrolyzing motor in Chlamydomonas reinhardtii,but little is known about its architecture and assembly.Here,we report the 3.2-Åresolution structure of the Chlamydomonas Orf2971–FtsHi complex.The 20-subunit complex spans the chloroplast inner envelope,with two bulky modules protruding into the intermembrane space and stromal matrix.Six subunits form a hetero-hexamer that potentially provides the pulling force through ATP hydrolysis.The remaining subunits,including potential enzymes/chaperones,likely facilitate the complex assembly and regulate its proper function.Taken together,our results provide the structural foundation for a mechanistic understanding of chloroplast protein translocation.

基于双目线结构光的承轨台测量

针对现有承轨台检测方法中存在的问题,提出一种基于改进的双目线结构光传感器的承轨台测量方法。测量时双目传感器中两个相机与承轨台之间的相对位置保持不变,通过传感器内置的驱动装置控制线激光器移动完成承轨台的扫描,获得点云数据,这提高了承轨台预埋套管位置的数据采集效果和测量精度。在承轨台点云数据处理方面,提出了基于Spearman秩相关系数的点云数据分割提取方法,根据参数定义,实现承轨台5项关键几何参数的自动非接触测量。实验结果表明,所提测量方法精度可达0.3 mm,满足轨道板检测的要求。

Single-cell transcriptomic profiling unravels the adenoma-initiation role of protein tyrosine kinases during colorectal tumorigenesis

The adenoma-carcinoma sequence is a well-accepted roadmap for the development of sporadic colorectal cancer.However,cellular heterogeneity in aberrant epithelial cells limits our understanding of carcinogenesis in colorectal tissues.Here,we performed a single-cell RNA sequencing survey of 54,788 cells from patient-matched tissue samples,including blood,normal tissue,para-cancer,polyp,and colorectal cancer.

Low rumen degradable starch promotes the growth performance of goats by increasing protein synthesis in skeletal muscle via the AMPK-mTOR pathway

Since starch digestion in the small intestine provides more energy than digestion in the rumen of ru-minants,reducing dietary rumen degradable starch(RDS)content is beneficial for improving energy utilization of starch in ruminants.The present study tested whether the reduction of rumen degradable starch by restricting dietary corn processing for growing goats could improve growth performance,and further investigated the possible underlying mechanism.In this study,twenty-four 12-wk-old goats were selected and randomly allocated to receive either a high RDS diet(HRDS,crushed corn-based concen-trate,the mean of particle sizes of corn grain=1.64 mm,n=12)or a low RDS diet(LRDS,non-processed corn-based concentrate,the mean of particle sizes of corn grain>8 mm,n=12).Growth performance,carcass traits,plasma biochemical indices,gene expression of glucose and amino acid transporters,and protein expression of the AMPK-mTOR pathway were measured.Compared to the HRDS,LRDS tended to increase the average daily gain(ADG,P=0.054)and decreased the feed-to-gain ratio(F/G,P<0.05).Furthermore,LRDS increased the net lean tissue rate(P<0.01),protein content(P<0.05)and total free amino acids(P<0.05)in the biceps femoris(BF)muscle of goats.LRDS increased the glucose concen-tration(P<0.01),but reduced total amino acid concentration(P<0.05)and tended to reduce blood urea nitrogen(BUN)concentration(P=0.062)in plasma of goats.The mRNA expression of insulin receptors(INSR),glucose transporter 4(GLUT4),L-type amino acid transporter 1(LAT1)and 4F2 heavy chain(4F2hc)in BF muscle,and sodium-glucose cotransporters 1(SGLT1)and glucose transporter 2(GLUT2)in the small intestine were significantly increased(P<0.05)in LRDS goats.LRDS also led to marked activation of p70-S6 kinase(S6K)(P<0.05),but lower activation of AMP-activated protein kinase(AMPK)(P<0.05)and eukaryotic initiation factor 2a(P<0.01).Our findings suggested that reducing the content of dietary RDS enhanced postruminal starch digestion and increased plasma glucose,thereby improving amino acid utilization and promoting protein synthesis in the skeletal muscle of goats via the AMPK-mTOR pathway.These changes may contribute to improvement in growth performance and carcass traits in LRDS goats.

Structural insights into photosynthetic cyclic electron transport

During photosynthesis,light energy is utilized to drive sophisticated biochemical chains of electron transfers,converting solar energy into chemical energy that feeds most life on earth.Cyclic electron transfer/flow(CET/CEF)plays an essential role in efficient photosynthesis,as it balances the ATP/NADPH ratio required in various regulatory and metabolic pathways.Photosystem I,cytochrome b6f,and NADH dehydrogenase(NDH)are large multisubunit protein complexes embedded in the thylakoid membrane of the chloroplast and key players in NDH-dependent CEF pathway.Furthermore,small mobile electron carriers serve as shuttles for electrons between these membrane protein complexes.Efficient electron transfer requires transient interactions between these electron donors and acceptors.Structural biology has been a powerful tool to advance our knowledge of this important biological process.A number of structures of the membrane-embedded complexes,soluble electron carrier proteins,and transient complexes composed of both have now been determined.These structural data reveal detailed interacting patterns of these electron donor-acceptor pairs,thus allowing us to visualize the different parts of the electron transfer process.This review summarizes the current state of structural knowledge of three membrane complexes and their interaction patterns with mobile electron carrier proteins.

Low copy numbers for mitochondrial DNA moderates the strength of nuclear-cytoplasmic incompatibility in plants

Plant cells contain only small amounts of mitochondrial DNA(mtDNA), with the genomic information shared among multiple mitochondria.The biological relevance and molecular mechanism underlying this hallmark of plant cells has been unclear. Here, we report that Arabidopsis thaliana plants exhibited significantly reduced growth and mitochondrial dysfunction when the mtDNA copy number was increased to the degree that each mitochondrion possessed DNA.The amounts of mitochondrion-encoded transcripts increased several fold in the presence of elevated mtDNA levels. However, the efficiency of RNA editing decreased with this excess of mitochondrion-encoded transcripts, resulting in impaired assembly of mitochondrial complexes containing mtDNA-encoded subunits, such as respiratory complexes I and IV. These observations indicate the occurrence of nuclear–mitochondrial incompatibility in the cells with increased amounts of mtDNA and provide an initial answer to the fundamental question of why plant cells have much lower mtDNA levels than animal cells. We propose that keeping mtDNA levels low moderates nuclear–mitochondrial incompatibility and that this may be a crucial factor driving plant cells to restrict the copy numbers of mtDNA.

Crystal Structure Analysis of Extrinsic PsbP Protein of Photosystem II Reveals a Manganese- Induced Conformational Change

The Mn cluster （Mn4CaO5） on the thylakoid luminal side of photosystem II （PSII） catalyzes the photosynthetic oxygen-evolving reaction, an essential process for life on Earth. In higher plants and green algae, the Mn cluster is surrounded by the membraneextrinsic proteins PsbO （33 kDa）, PsbP （23 kDa）, and PsbQ （17 kDa） （Murata and Miyao, 1985）.