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Human protamines and the developing spermatid: their structure, function, expression and relationshipwith male infertility

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Asian Journal of andrology 2003年第4期5卷 315-324页

作者： Vincent W. Aoki Douglas T. Carrell andrology and ivf laboratories University of Utah School of Medicine Salt Lake City UT 84108 USAAndrology and IVF Laboratories University of Utah School of Medicine Salt Lake City UT 84108 USA

During spermiogenesis, the protamine proteins play an integral role in spermatid chromatin compaction. Recent research has focused on many facets of protamine biology, including protamine gene and protein structure/ function relationships, mechanisms of protamine expression regulation and involvement of the protamines in male fertility. In this paper, we review our current understanding of the structure and function of the protamine-1 (P1) and protamine-2 (P2) proteins and genes, the expression and regulation of these genes and the relationship between the protamines and male fertility. In addition, we offer a brief outlook on future investigation into protamine proteins.

关键词： protamines spermatids male infertility spermatid transition proteins

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An ensemble and cost-sensitive learning-based root cause diagnosis scheme for wireless networks with spatially imbalanced user data distribution

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Science China(Information Sciences) 2024年第7期67卷 331-332页

作者： Qi WANG Zhiwen PAN Nan LIU National Mobile Communications Research Laboratory Southeast University Purple Mountain laboratories

Root cause diagnosis, a key component of self-healing, plays a vital role in fault management. The spatially imbalanced network key performance indicators (KPIs) reported by users increase the difficulty of identifying root *** [1,2], the image inpainting technique is inspired to address issues caused by sparse reports across the coverage area.

关键词： Wireless networks

Slicing capacity-centered mode selection and resource optimization for network-assisted full-duplex cell-free distributed massive MIMO systems

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Science China(Information Sciences) 2024年第1期67卷 203-220页

作者： Jie WANG Jiamin LI Pengcheng ZHU Dongming WANG Hongbiao ZHANG Yue HAO Bin SHENG National Mobile Communications Research Laboratory Southeast University 2. Purple Mountain Laboratories China Mobile Research Institute

Network-assisted full-duplex(NAFD) cell-free distributed massive multiple-input multipleoutput(MIMO) systems enable uplink(UL) and downlink(DL) communications within the same timefrequency resources,which potentially reduce latency by avoiding the overhead of switching UL/DL ***,how to choose UL/DL modes remains an important factor affecting system *** the dramatic increase in the number of users and access points(APs),massive access brings significant overhead in the mode ***,the different quality of service(QoS) among users also makes the effective utilization of resources *** one of the most promising technologies in sixth-generation(6G),network slicing enables the adaptive configuration of limited UL/DL resources through the resource isolation assisted NAFD ***,we propose a slicing capacity-centered *** this scheme,APs are motivated by slicing requirements and associated slices to form different *** mode selection and resource allocation are performed within each subsystem to reduce overhead and improve resource *** implement this scheme efficiently,a double-layer deep reinforcement learning(DRL)mechanism is used to realize the joint optimization of mode selection and resource *** results show that the slicing capacity-centered scheme can effectively improve resource utilization and reduce overhead.

关键词： network-assisted full-duplex network slicing mode selection resource optimization deep reinforcement learning

Distortion-aware beamforming design for multi-beam satellite communications with nonlinear power amplifiers

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Science China(Information Sciences) 2024年第6期67卷 359-369页

作者： Xiang XIAO Li YOU Kezhi WANG Xiqi GAO National Mobile Communications Research Laboratory Southeast University Purple Mountain laboratories Department of Computer Science Brunel University London

Hardware components can cause different impairments, including power amplifier(PA) nonlinearities, which inevitably impact the system performance of satellite communications(SATCOM). In this work, we consider a multi-beam SATCOM downlink system and investigate the distortion-aware beamforming scheme with the characteristics of PA non-linearities. Notably, we aim to maximize the resource efficiency(RE), defined as the weighted sum of energy efficiency(EE) with spectral efficiency(SE), to obtain a flexible EE-SE tradeoff while accounting for the characteristics of PA distortion and the total power *** that the optimization objective is a sum of ratios and the high non-convexity involved in constraints,we propose an efficient approach that exploits the quadratic transformation, the Lagrange multiplier method,and the gradient ascent approach to handle this issue. Simulation results demonstrate the effectiveness of the distortion-aware beamforming approach in achieving the EE-SE tradeoff and exhibit a substantial RE performance gain over the conventional approach with ideal linear PAs assumed at the satellite transmitters.

关键词： multi-beam satellite communications nonlinear power amplifier energy and spectral efficiency tradeoff resource efficiency robust beamforming

Mitigating set-stuck failure in 3D phase change memory: substituting square pulses with surge pulses

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Science China(Information Sciences) 2024年第5期67卷 295-301页

作者： Ninghua LI Wang CAI Jun XIANG Hao TONG Weiming CHENG Xiangshui MIAO School of Integrated Circuits Huazhong University of Science and Technology Hubei Yangtze Memory laboratories Hubei Institute of Measurement and Testing Technology

In the devices that integrate phase change memory(PCM) and ovonic threshold switching(OTS),the OTS threshold voltage often surpasses the RESET operation voltage of PCM. The conventional application of square pulses hinders the successful completion of the SET operation in these integrated devices. To address this challenge, a novel pulse called the surge pulse is introduced, which comprises a high amplitude pulse for OTS activation and a low amplitude pulse for PCM operation. By employing COMSOL simulation,the operational effectiveness of both square pulses and surge pulses is validated. Test results reveal that using a square pulse to operate the integrated device accelerates the occurrence of SET-stuck failure(SSF).In contrast, the surge pulse enables the integrated device to operate for at least 1000 cycles while preserving the essential cyclic characteristics. Additionally, an investigation into the overshoot component of the surge pulse is conducted, revealing that an increase in overshoot amplitude and pulse width also accelerates the emergence of SSF. By applying the theory of ion migration induced by the electric field, the root cause of SSF in integrated devices is explained, and the accuracy of the theory is validated through the application of a reverse pulse. In summary, this study elucidates the rationality of replacing the square pulse with a surge pulse, presenting a superior approach for operating PCM and OTS integrated devices.

关键词： surge pulse phase change memory (PCM) integration SET-stuck failure (SSF) square pulse

Semen analysis standardization： is there any problem in Polish laboratories？

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Asian Journal of andrology 2013年第5期15卷 616-621页

作者： Renata Walczak-Jedrzejowska Katarzyna Marc hlewsks Elzbieta Oszukowska Eliza Filipiak Leszek Bergier Jolanta Slowikowska-Hilczer Division of andrology Department of Andrology and Reproductive Endocrinology Medical University of Lodz 91-425 Lodz Poland Division of Reproductive Endocrinology Department of Andrology and Reproductive Endocrinology Medical University of Lodz 91-425 Lodz Poland Diagnostyka Company Ltd Medical Laboratories 31-513 Cracow Poland

The aim of the study was to determine the degree of compliance of Polish laboratories with World Health Organization （WHO） recommendations, with regard to semen analysis methodology. A survey requesting information about methods of semen analysis was distributed to employees of 55 laboratories. Respondents who had participated in external seminological workshops （31%） were termed certified respondents （CR）, the remaining （69%）--non-certified respondents （NCR）. Only one laboratory （6%） in the CR group and none in the NCR were compliant with WHO guidelines for methods and equipment used to evaluate seminal volume, sperm motility, concentration, vitality and morphology. Most problems were of volume measurement （weighing method was reported by 17% of CR and 10% of NCR） and staining method for sperm morphology （Papanicolau or Diff-Quik were found in 33% of CR and 23% of NCR）. A three- or four-point grading of sperm motility was used by the majority of respondents; however, 17% of CR and 37% of NCR did not use a laboratory counter to tally spermatozoa. Although a haemocytometer method was used by 80% of laboratories in each group, the improved Neubauer chamber was used only by 42% of CR and 19% of NCR. In each group, 24% of laboratories did not perform a vitality test. Procedural errors and the interchangeable utilization of two or even three methods to analyse a given parameter was observed in both groups. The results indicate a need for standardisation of the methods and continuous, unified training in semen analysis in Polish laboratories.

关键词： clinical laboratory compliance semen analysis World Health Organization

Weathering and accumulation of trace elements in the soils of the Porali Plain, Balochistan: repercussions in agriculture

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Acta Geochimica 2024年第2期43卷 214-234页

作者： Maria Kaleem Erum Bashir Shahid Naseem Tahir Rafique Bushra Shahab Department of Geology University of KarachiKarachi 75270Pakistan Applied Chemistry Research Centre PCSIR Laboratories ComplexKarachi 75280Pakistan

This study is theﬁrst attempt to assess the nature of the soil,especially on the western side of the Porali Plain in Balochistan;a new emerging agriculture hub,using weathering and pollution indices supplemented by multi-variate analysis based on geochemical *** outcomes of this study are expected to help farmers in soil manage-ment and selecting suitable crops for the ***-ﬁve soil samples were collected,mainly from the arable land of the Porali *** drying and coning-quarter-ing,soil samples were analyzed for major and trace ele-ments using the XRF technique;sieving and hydrometric methods were employed for granulometric ***-mated data were analyzed using Excel,SPSS,and Surfer software to calculate various indices,correlation matrix,and spatial *** granulometric analysis showed that 76%of the samples belonged to loam types of soil,12%to sand type,and 8%to silt *** indices:CIA,CIW,PIA,PWI,WIP,CIX,and ICV were calculated to infer the level of *** indices reﬂect mod-erate to intense weathering;supported by K_(2)O/AI_(2)O_(3),Rb/K_(2)O,Rb/Ti,and Rb/Sr *** of the geo-ac-cumulation and Nemerow Pollution indices pinpoint rela-tively high concentrations of Pb,Ni,and Cr concentration in the *** correlation matrix and Principal Compo-nent Analysis show that the soil in this study area is mainly derived from the weathering of igneous rocks of Bela Ophiolite(Cretaceous age)and Jurassic sedimentary rocks of Mor Range having SEDEX/MVT type *** may result in the undesirable accumulation of certain trace elements which adversely affects crops.

关键词： Weathering indices Pollution indices Accumulation Repercussions Trace elements Multivariate analyses Porali Plain Balochistan

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Efficient implementation of majority-inverter graph logic and arithmetic functions with memristor arrays

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Science China(Information Sciences) 2024年第7期67卷 345-346页

作者： Zhouchao GAN Dongdong ZHANG Chenyu ZHANG Yinghao MA Xiangshui MIAO Xingsheng WANG School of Integrated Circuits & Wuhan National Lab. for Optoelectronics Huazhong University of Science and Technology Hubei Yangtze Memory laboratories

Memristors are characterized by several outstanding features that permit them to function both as memory and logic units, enabling logic-in-memory (LIM) computing that potentially breaks the von Neumann bottleneck. Typically,in-memory logic is categorized into stateful logic and nonstateful logic based on the physical quantities of inputs and outputs.

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A Retrodirective Array Enabled by CMOS Chips for Two-Way Wireless Communication with Automatic Beam Tracking

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Engineering 2024年第6期37卷 196-207页

作者： Jiacheng Guo Yizhu Shen Guoqing Dong Zhuang Han Sanming Hu State Key Laboratory of Millimeter Waves School of Information Science and EngineeringSoutheast UniversityNanjing 210096China Purple Mountain laboratories Nanjing 211111China

This article proposes and demonstrates a retrodirective array(RDA)for two-way wireless communication with automatic beam *** proposed RDA is enabled by specifically designed chips made using a domestic complementary metal-oxide semiconductor(CMOS)*** highly integrated CMOS chip includes a receiving(Rx)chain,a transmitting(Tx)chain,and a unique tracking phaselocked loop(PLL)for the crucial conjugated phase recovery in the *** article also proposes a method to reduce the beam pointing error(BPE)in a conventional *** validate the above ideas simply yet without loss of generality,a 2.4 GHz RDA is demonstrated through two-way communication links between the Rx and Tx chains,and an on-chip quadrature coupler is designed to achieve a nonretrodirective signal suppression of 23 *** experimental results demonstrate that the proposed RDA,which incorporates domestically manufactured low-cost 0.18 lm CMOS chips,is capable of automatically tracking beams covering±40with a reduced *** CMOS chip in the RDA has a compact size of 4.62 mm^(2) and a low power consumption of 0.15 *** the best of the authors’knowledge,this is the first research to demonstrate an RDA with a fully customized CMOS chip for wireless communication with automatic beam tracking。

关键词： Automatic beam tracking CMOS Retrodirective array Two-way communication