为提高物流仓储定位效率与精度,提出基于射频识别(Radio Frequency Identification,RFID)电子标签的物联网物流仓储智能定位研究。首先,以芯片、天线作为射频标签的核心,设计物联网物流仓储物资RFID信息编码规则;其次,结合自动导引运输...为提高物流仓储定位效率与精度,提出基于射频识别(Radio Frequency Identification,RFID)电子标签的物联网物流仓储智能定位研究。首先,以芯片、天线作为射频标签的核心,设计物联网物流仓储物资RFID信息编码规则;其次,结合自动导引运输车(Automated Guided Vehicle,AGV)和RFID射频识别技术识别标签,基于标签地点信息,实现物流仓储信息的序列编码;最后,引进空间传输模型,在考虑信号传输距离损失的基础上,设计基于接收信号强度指示(Received Signal Strength Indicator,RSSI)测距的仓储智能定位。实验结果表明,设计方法可以提高仓储定位精度和定位工作的时效性,为物流管理提供技术支持。展开更多
新兴的染色质靶向切割和标签化(clevage under target and tagment,CUT&Tag)技术利用转座酶在目标蛋白结合的DNA附近进行切割并对切割下的DNA片段进行标签化,通过后续的二代测序可以快速鉴定蛋白质-DNA相互作用,极大的简化了染色质...新兴的染色质靶向切割和标签化(clevage under target and tagment,CUT&Tag)技术利用转座酶在目标蛋白结合的DNA附近进行切割并对切割下的DNA片段进行标签化,通过后续的二代测序可以快速鉴定蛋白质-DNA相互作用,极大的简化了染色质免疫共沉淀测序(chromatin immunoprecipitation sequencing,ChIP-seq)的实验过程。CUT&Tag中转座酶完成标签化后需要DNA回收或其他后处理才能进行建库PCR,不同的回收方法对CUT&Tag结果有着显著的影响。通过建立生物素化转座体-链霉亲和素磁珠体系(streptavidin beads recovery CUT&Tag,srCUT&Tag),可以快速便捷地完成CUT&Tag的产物回收。本文在K562细胞中展开H3K4me3、RNA聚合酶Ⅱ(RNA polymeraseⅡ,RNAPⅡ)、转录因子CTCF和HMGA1的CUT&Tag实验,并利用现有的乙醇沉淀、片段分选(solid-phase reversible immobilization,SPRI)磁珠回收和直接PCR法,以及本研究建立的srCUT&Tag方法对产物进行回收。结果表明,从整体上看,SPRI磁珠回收和srCUT&Tag方法着较高的回收效率,而乙醇沉淀法则回收效率低下。在全部4种CUT&Tag产物回收过程中,SPRI磁珠回收均会损失大部分小于150 bp的产物片段。在CTCF和HMGA1 CUT&Tag产物的回收中,直接PCR法则损失了大部分大于300 bp的片段并与其他回收方法的结果有较大的差别。因此,srCUT&Tag能够比其他三种回收方法提供更多更完整的测序信息。综上所述,新建立srCUT&Tag回收方法相比现有的CUT&Tag产物回收方法能提高建库效率并得到更好的数据质量,为表观遗传学研究提供了更好的技术选择。展开更多
Objective: To screen the stage-specific expression genes from rat spermatogonia, pachytene spermatocytes and round spermatids. Methods: Highly purified spermatogonia were isolated from 9-day-old rats, pachytene sperma...Objective: To screen the stage-specific expression genes from rat spermatogonia, pachytene spermatocytes and round spermatids. Methods: Highly purified spermatogonia were isolated from 9-day-old rats, pachytene spermatocytes and round spermatids from adult rats by sedimentation velocity at unit gravity, using 2%-4% BSA gradient in DMEM/F12 medium. A mRNA differential display method was used for screening the stage-specific expression gene. Results: Nineteen differentially expressed cDNA fragments were obtained. After excluding the false positive cDNA fragments by dot blot, 13 cDNAs were selected to clone and sequence. To obtain longer cDNAs, six ESTs were used to screen the rat testis λ-zap II cDNA library. Two longer cDNA fragments, designated as LY21 and LM66, were obtained. The analysis with DNAMAN software indicated that LY21 had a long open reading frame coding 372 amino acids while LM66 had no long open reading frame. LY21 were highly homologous with hnRNP H1. To observe the expression patterns of LY21 gene in the testicular cells, we performed in situ hybridization on testis sections from adult rats. The LY21 gene expression was found in the spermatogonia and primary spermatocytes.Conclusion: This study indicated that LY21 gene was associated with spermatogenesis. Further studies will be needed to explore the function of LY21.展开更多
文摘为提高物流仓储定位效率与精度,提出基于射频识别(Radio Frequency Identification,RFID)电子标签的物联网物流仓储智能定位研究。首先,以芯片、天线作为射频标签的核心,设计物联网物流仓储物资RFID信息编码规则;其次,结合自动导引运输车(Automated Guided Vehicle,AGV)和RFID射频识别技术识别标签,基于标签地点信息,实现物流仓储信息的序列编码;最后,引进空间传输模型,在考虑信号传输距离损失的基础上,设计基于接收信号强度指示(Received Signal Strength Indicator,RSSI)测距的仓储智能定位。实验结果表明,设计方法可以提高仓储定位精度和定位工作的时效性,为物流管理提供技术支持。
基金the Special Funds for Major State Basic Research project (G199055901).
文摘Objective: To screen the stage-specific expression genes from rat spermatogonia, pachytene spermatocytes and round spermatids. Methods: Highly purified spermatogonia were isolated from 9-day-old rats, pachytene spermatocytes and round spermatids from adult rats by sedimentation velocity at unit gravity, using 2%-4% BSA gradient in DMEM/F12 medium. A mRNA differential display method was used for screening the stage-specific expression gene. Results: Nineteen differentially expressed cDNA fragments were obtained. After excluding the false positive cDNA fragments by dot blot, 13 cDNAs were selected to clone and sequence. To obtain longer cDNAs, six ESTs were used to screen the rat testis λ-zap II cDNA library. Two longer cDNA fragments, designated as LY21 and LM66, were obtained. The analysis with DNAMAN software indicated that LY21 had a long open reading frame coding 372 amino acids while LM66 had no long open reading frame. LY21 were highly homologous with hnRNP H1. To observe the expression patterns of LY21 gene in the testicular cells, we performed in situ hybridization on testis sections from adult rats. The LY21 gene expression was found in the spermatogonia and primary spermatocytes.Conclusion: This study indicated that LY21 gene was associated with spermatogenesis. Further studies will be needed to explore the function of LY21.
