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Effect of herbal medicine Juzentaihoto on hepatic and intestinal heat shock gene expression requires intestinal microflora in mouse

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World Journal of Gastroenterology 2007年第16期13卷 2289-2297页

作者： Miho Kato atsushi Ishige Naoko Anjiki Masahiro Yamamoto Yoshifumi Irie Mitsue Taniyama Ryoko kibe Junichiro Oka Yoshimi Benno Kenji Watanabe Department of Kampo Medicine Keio University School of Medicine 35 Shinano-machi Shinjuku-ku Tokyo 160-8582 Japan Faculty of Pharmaceutical Science Tokyo University of Science 264 Yamazaki Noda City Chiba 278-8519 Japan Japan Collection of Microorganisms Riken 2-1 Hirosawa Wako-shi Saitama 351-0198 Japan Department of Kampo Medicine Keio University School of Medicine 35 Shinano-machi Shinjuku-ku Tokyo 160-8582 Japan Department of Kampo Medicine Keio University School of Medicine 35 Shinano-machi Shinjuku-ku Tokyo 160-8582 Japan Pharmacology Research Department Tsumura Research Institute Research Division 3586 Yoshiwara Ami-machi Inashiki-gun Ibaraki 300-1192 Japan Pharmacology Research Department Tsumura Research Institute Research Division 3586 Yoshiwara Ami-machi Inashiki-gun Ibaraki 300-1192 Japan Japan Collection of Microorganisms Riken 2-1 Hirosawa Wako-shi Saitama 351-0198 Japan Faculty of Pharmaceutical Science Tokyo University of Science 264 Yamazaki Noda City Chiba 278-8519 Japan

AIM： To evaluate the role of intestinal microflora in the effects of multi-herbal medicine on gene expression in the gut and liver. METHODS： The multi-herbal medicine Juzentaihoto （JTX） was administered to five germ-free mice and regular mice for 2 wk. Among the results of the comprehensive gene chip analysis of the intestine and liver, we featured heat shock proteins （HSPs） 70 and 105 because their gene expression changed only in the presence of microflora. Real-time RT-PCR was performed to confirm the expression levels of these HSP genes. To determine whether JTX acts directly on the HSP genes, sodium arsenite （SA） was used to induce the heat shock proteins directly. To examine the change of the intestinal microflora with administration of JTX, the terminal restriction fragment polymorphism （T-RFLP） method was used. To identify the changed bacteria, DNA sequencing was *** by gene chip and real-time RT-PCR, changed with the administration of JTX in the regular mice but not in the germ-free mice. JTX did not suppress the direct induction of the HSPs by SA. T-RFLP suggested that JTX decreased unculturable bacteria and increased Lactobacillus johnsoni. These data suggested that JTX changed the intestinal microflora which, in turn, changed HSP gene ***： Intestinal microflora affects multi-herbal product JTX on the gene expression in the gut and liver.

关键词： Herbal medicine Juzentaihoto Intestinal microflora Terminal restriction fragment length polymorphism Heat shock protein

The expression of Spodoptera exigua P450 and UGT genes: tissue specificity and response to insecticides

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Insect Science 2019年第2期26卷 199-216页

作者： Bo Hu Shu-Heng Zhang Miao-Miao Ren Xiang-Rui Tian Qi Wei David kibe Mburu Jian-Ya Su Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education) College of Plant Protection Nanjing Agricultural University Nanjing China

Cytochrome P450 and UDP-glucosyltransferase (UGT) as phase I and phase II metabolism enzymes, respectively, play vital roles in the breakdown of endobiotics and xenobiotics. Insects can in crease the expression of detoxificatio n enzymes to cope with the stress from xenobiotics including insecticides. However, the molecular mechanisms for insecticide detoxification in Spodoptera exigua remain elusive, and the genes conferring insecticide metabolisms in this species are less well reported. In this study, 68 P450 and 32 UGT genes were identified. Phylogenetic analysis showed gene expansions in CYP3 and CYP4 clans of P450 genes and UGT33 family of this pest. P450 and UGT genes exhibited specific tissue expression patterns. Insecticide treatments in fat body cells of S. exigua revealed that the expression levels of P450 and UGT genes were significantly influenced by challenges of abamectin, lambda-cyhalothrin, chlorantraniliprole, metaflumizone and indoxacarb. Multiple genes for detoxification were affected in expression levels after insecticide exposures. The results demonstrated that lambda-cyhalothrin, chlorantraniliprole, metaflumizone and indoxacarb induced similar responses in the expression of P450 and UGT genes in fat body cells;eight P450 genes and four UGT genes were co-up-regulated significantly, and no or only a few CYP/UGT genes were down-regulated significantly by these four insecticides. However, abamectin triggered a distinct response for P450 and UGT gene expression;more P450 and UGT genes were down-regulated by abamectin than by the other four compounds. In con elusion, P450 and UGT genes from S. exigua were identified, and different responses to abamectin suggest a different mechanism for insecticide detoxification.

关键词： abamectin cytochrome P450 monooxygenases gene expression insecticide Spodoptera exigua UDP-glycosyltransferase

Adaptive Cluster Head Selection Scheme for High Mobility Based IEEE 802.15.6 Wireless Body Area Networks

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Journal of Sensor Technology 2018年第2期8卷 35-47页

作者： Anthony Mile George Okeyo Ann kibe School of Computing and Information Technology Jomo Kenyatta University of Agriculture and Technology Nairobi Kenya

Due to the development in the field of Wireless Sensor Networks (WSNs), its major application, Wireless Body Area Network (WBAN) has presently become a major area of interest for the developers and researchers. Efficient sensor nodes data collection is the key feature of any effective wireless body area network. Prioritizing nodes and cluster head selection schemes plays an important role in WBAN. Human body exhibits postural mobility which affects distances and connections between different sensor nodes. In this context, we propose maximum consensus based cluster head selection scheme, which allows cluster head selection by using Link State. Nodal priority through transmission power is also introduced to make WBAN more effective. This scheme results in reduced mean power consumption and also reduces network delay. A comparison with IEEE 802.15.6 based CSMA/CA protocol with different locations of cluster head is presented in this paper. These results show that our proposed scheme outperforms Random Cluster head selection, Fixed Cluster head at head, Foot and Belly positions in terms of mean power consumption, network delay, network throughput and bandwidth efficiency.

关键词： Adaptive Cluster Head CSMA/CA LST Nodal Priority WBAN

Hybrid IEEE 802.15.6 Wireless Body Area Networks Interference Mitigation Model for High Mobility Interference Scenarios

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Wireless Engineering and Technology 2018年第2期9卷 34-48页

作者： Anthony Mile George Okeyo Ann kibe School of Computing and Information Technology Jomo Kenyatta University of Agriculture and Technology Nairobi Kenya

The field of Wireless Sensor Networks (WSNs) has revolutionized tremendously in the recent past with its major application in Wireless Body Area Networks (WBANs). This has in the same dimension attracted immense interests from the researchers and technology providers. The operational modality of the WBANs is that a few sensor nodes are placed in or around the body and that they are meant to operate within a limited condition while providing high performance in terms of WBAN life time, high throughput, high data reliability, minimum or no delay and low power consumption. As most of the WBAN operates within the universal Industrial, Scientific and Medical (ISM) Narrow Band (NB) wireless band (2.4 Ghz) frequency band, this has posed a challenge in respect to inter, intra and co-channel interference especially in dense areas and high mobility scenarios. As well the body posture changes dynamically due to these mobility effects. In this paper, we propose a hybrid WBAN interference mitigation model based on Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) Contention Window (CW) approach and User Priority (UP) queues. Using Omnet++ simulation, a comparison to the IEEE 802.15.6 based WBAN protocol is presented under the standing, walking sitting and Lying postural mobility scenarios. The results show that the proposed hybrid model outperforms IEEE 802.15.6 based CSMA/CA protocol in areas of network throughput, bandwidth efficiency and network delay in these mobility postures.

关键词： IEEE 802.15.6 Interference Mitigation WBAN Mobility Priority Queues CSMA/CA

Growth Parameters of DK8031 Maize Variety as Affected by Varying Irrigation and Nitrogen Fertilizer Rates in Embu County, Kenya

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Journal of Environmental Science and Engineering(A) 2015年第8期4卷 432-444页

作者： Charles Nyambane Onyari Antony Mwangi kibe Samuel Mwonga Department of Land and Water Management Embu University EMB U 6-60100 Kenya Department of Crops Horticulture and Soils Egerton University EGERTON 536 Kenya

Determination of crop growth parameters of maize helps assess the performance of the crop for food security. A study was conducted in two seasons covering 2012 and 2013 to establish optimal irrigation and nitrogen fertilizer rates for drought tolerant hybrid maize （Zea mays L.）, DK8031 variety, in sandy loam soils using furrow irrigation. Four additive irrigation levels （119.05 mm, 238.10 mm, 357.15 mm and 476.2 mm） were allocated the main plots while five nitrogen fertilizer rates （0 kg/ha, 60, 75 kg/ha, 90 kg/ha and 100 kg/ha） were allocated the sub-plots. Both irrigation and nitrogen fertilizer treatments significantly enhanced crop growth parameters under consideration. Stand count per treatment plot, plant height and number of leaves per ranged from 45-59 plants/plot, 215-238 cm and 14-16 leaves respectively. It was concluded that use of supplementary irrigation and phased nitrogen fertilizer rates for maize growing in areas such as Embu can greatly promote crop growth.

关键词： Maize irrigation nitrogen fertilizer rates plant height leaves per plant.

适合于强度调制/直接检测的QAM/QPSK调制方案

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适合于强度调制/直接检测的QAM/QPSK调制方案

作者： kibe Lynette Wanjeri 兰州理工大学

学位级别：硕士

自由空间光通信是以激光作为信息传输的载体,能够实现高速率数据传输的一种新兴的无线通信方式。具有宽带、高速、低成本、通信安全保密、无需频率许可等优点。它的使用可以减少新的通信网络的建设投资,使工程造价大幅下降,也可以作为... 详细信息

自由空间光通信是以激光作为信息传输的载体,能够实现高速率数据传输的一种新兴的无线通信方式。具有宽带、高速、低成本、通信安全保密、无需频率许可等优点。它的使用可以减少新的通信网络的建设投资,使工程造价大幅下降,也可以作为光纤通信和微波通信的紧急后备措施,还可用于数据网、电话网、移动通信网和视频传输及不便铺设光缆的地区,被认为是解决“最后一公里”问题的最佳方案,同时,也可用于军事通信或其他要害部门及需要严格保密的场合等,具有广泛的市场应用前景。近年来,随着半导体激光器和光电探测器技术的不断发展,空间光通信越来越引起了人们关注,但自由空间光通信也面临着挑战,主要表现在:(1)由于大气对光信号的吸收和散射会产生大气衰减,即使在晴朗天空也会存在衰减;(2)大气的湍流运动会引起光斑的漂移和闪烁。特别是在强湍流情况下,光信号受到严重干扰甚至脱靶,造成较大的误码率和短时间通信中断,严重影响激光通信的稳定性和可靠性;(3)在实际使用中,虽然光载波的频率很高,光通信系统的信号带宽可以超过1THz。但由于光色散或电子器件速度的限制,传输速率常常被限制到10Gb/s或者更低;(4)实现高精度的捕获、跟踪和瞄准(ATP)技术存在一定的困难。尤其是窄光束实现高精度的捕获、跟踪和瞄准难度更大;(5)考虑到对人眼安全的影响,发射天线提供的光功率受限。面对自由空间光通信中存在的问题,人们采用不同的措施来解决。目前,常采用的技术主要有波分复用(WDM)、偏振复用(PDM)、成像通信、多输入多输出传输(MIMO)、高码率调制技术、更高阶的调制技术(如多进制PPM和MPPM等)和更优良的信道编码方法(如TURBO码、LDPC码等)等。相对于MIMO技术而言,其它几种技术虽然也能提高传输速率,但它们不能有效抑制湍流效应,也不能降低系统跟踪高精度的要求。另外,通过采用更高阶的调制技术和更优良的信道编码方法来提高系统的信道容量时,只能是逼近现有的单输入单输出系统(Single Input Single Output,SISO)的信道容量,但单输入单输出系统的信道容量毕竟也是受限的。而多输入多输出技术(MIMO)是通过同时获得发送和接收分集增益来获得更高的频谱利用率,进而提高通信系统的信道容量,并且不会给系统增加额外的负担。综合考虑各种影响因素,在自由空间光通信中,采用MIMO技术不仅可以在不额外占用频谱资源和发送功率的情况下,成倍提高现有系统的信道容量,而且能有效抑制湍流效应。在目前的半导体器件技术和精密光学元器件发展技术水平下,MIMO技术是解决自由空间光通信面临问题的良好措施。在相同发射功率和传输带宽下,采用空间分集技术的MIMO系统较SISO系统的信道容量大大提高,有时甚至高达几十倍。而这些增加的信道容量既可以用来提高信息传输速率,也可以通过增加冗余来提高通信系统的可靠性,或者在二者之间取得一个合理的折衷。MIMO技术的思想起源于RF通信,它由于既能提高通信系统的信道容量又能抑制无线衰落而被广泛研究,并取得了丰硕的成果。鉴于此,人们将MIMO的思想也引入自由空间光通信用于解决光通信中存在的问题。早期有关光MIMO技术的研究,主要是将分集技术和强度调制相结合而展开。目前常见的强度调制方式主要有开关键空调制(OOK)和脉冲位置调制(PPM)等。OOK调制是载波振幅随着数字基带信号(数字基带信号为二进制)而变化的一种数字调制技术。它通过在每一比特间隔内使光源脉冲开或关来完成对每个比特信息的发送。它是调制光信号最基本的形式,具有结构简单和所需带宽较小优点,但这种调制方式所需的平均发射功率高,误码率较大。这就导致该方式不仅抗干扰能力差,而且传输效率也低。尤其在背景光比较强时,或者进行高速率通信时无法满足传输的要求,甚至通信无法正常进行。PPM调制是一种利用激光脉冲位置的不同来表示信息的一种调制方式,是一种正交的调制方式。PPM调制有效地提高OOK的功率效率,够满足高速率的通信。但是以增加的带宽需求和更大的复杂性为代价。PPM方案的最大缺点是通过增加更大的星座大小提高功率效率来降低带宽效率。在非视距传输中,由于多径引起的码间串扰,PPM在高数据速率下效果较差。这些调制方式虽然具有实现简单,体积小,重量轻等优点。然而,它们具有低的调制效率。为了有效解决该问题,高阶调制方式(如正交幅度调制,QAM;正交相移键控,QPSK)应用而生。正交幅度调制(QAM)是一种使用幅移键控(ASK)的数字调制方式,它通过调制正交载波的两个不同相位的振幅来传送两个信号。通过设置合适的星座大小,QAM实现了高频谱效率。正交相移键控(QPSK)是PSK调制的变体之一。它在星座图上使用四个不同的点,围绕一个圆圈等距地表示数据位。星座点帮助QPSK在表示数据时对每个符号进行两位编码。QAM/PSK调制方式具有

关键词：无线光通信系统强度调制/直接检测正交幅度调制正交相移键控

Effects of Calcium Nitrate Levels and Soaking Durations on Cocopeat Nutrient Content

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Journal of Agricultural Chemistry and Environment 2021年第3期10卷 372-388页

作者： Sheku N. Gbollie Samuel M. Mwonga Anthony M. kibe Department of Crops Horticulture and Soils Faculty of Agriculture Egerton University Njoro Kenya

Cocopeat, a by-product of the coconut (Cocos nucifera L.), is an important soilless media that contains high potassium (K), sodium (Na), and electrical conductivity (EC) depending on its source. Methods for extracting these elements and thus lowering EC are yet to be standardized. This study was therefore carried out to investigate two extraction methods of these elements in cocopeat. A greenhouse pot experiment was carried out at the Climate and Water Smart Agriculture Centre of Egerton University, Kenya. It was laid out in a 5 × 4 factorial completely randomized design. Five soaking durations (12, 24, 36, 48, and 72 hours) and four calcium nitrate (Ca(NO3)2) levels (0, 60, 100, and 150 g) were used. The experiment was done in two folds: the leachate and treated cocopeat examination for their chemical properties. The General Linear Model procedures were used for Analysis of Variance at (P ≤ 0.05). The results showed that the addition of Ca(NO3)2 100 g extracted significantly more K and Na in the leachate than Ca(NO3)2 0.0 g and 60 g. The EC levels in the leachate increased with the application levels of Ca(NO3)2 while the pH levels were reducing. In the treated cocopeat, Ca(NO3)2 100 g and soaking duration 36 hours significantly reduced K and Na and sufficiently supplemented Ca and N. Irrespective of Ca(NO3)2 and soaking durations, after the cocopeat is washed, the EC and pH values fall within their suitable ranges. There was a strong negative correlation between Ca and Na, Ca and K, and between Na and EC. Also, strong positive correlation between Ca and N and Ca and EC. Effective supplementation of Ca and N, and optimal reduction of K and Na by 78.44% and 92%, respectively can be achieved with 100 g of Ca(NO3)2 1.5 kg-1 of cocopeat in 15 liters of water with a soaking duration of 36 hours.

关键词： Calcium Nitrate Cocopeat Leachate Potassium Soaking

日本工程试验卫星ETS—Ⅶ无人自动交会对接系统的在轨演示

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控制工程（北京） 1997年第2期 50-56页

作者： Isao Kawano Masaaki Mokuno Hiroshi Horiguchi Koichi kibe

空间交会对接(RVD)技术是进行航天器在轨修复、空间站补给和设备更换等未来空间活动的必要技术。日本从事空间交会对接技术的研究,尤其受到在21世纪初期通过发射无人有翼往返运输系统(HOPE)实现为α国际空间站(SS)的日本实验舱(JEM)提... 详细信息

空间交会对接(RVD)技术是进行航天器在轨修复、空间站补给和设备更换等未来空间活动的必要技术。日本从事空间交会对接技术的研究,尤其受到在21世纪初期通过发射无人有翼往返运输系统(HOPE)实现为α国际空间站(SS)的日本实验舱(JEM)提供后勤支持服务的任务驱动。HOPE-SS交会对接任务的特点是由无人航天器向载人航天器实现RVD。NASDA筑波空间中心从70年代初期就开始从事RVD系统的研究工作,研究重点集中在开发高度自动和安全的RVD系统。目前,由工程试验卫星-Ⅶ(ETS-Ⅶ)在轨演示无人自动RVD系统的工程正在进展之中,ETS-Ⅶ将在1997年由H-Ⅶ运载火箭发射入轨,此次在轨飞行演示试验是NASDA开发RVD技术的第一步,其主要目的在于在不久将来即21世纪初发展自动RVD技术及空间遥操作机器人技术。本文将介绍ETS-ⅦRVD系统的初步研究成果,包括RVD试验计划、试验系统和运行方案。为实现自动和安全RVD系统,需建立星载飞行管理系统(FMS)。本文将描述制导、导航和控制系统(GNC)设计以及FMS策略。工程样机(EM)的设计工作开始于1994年冬天,并拟于1995年初在RVD系统测试中使用。本文也将报告RVD系统的验证确认计划及其地面测试设备。

关键词：工程试验卫星对接日本在轨演示交会对接系统

PITCHER PLANTS RECORDED FROM BRIS FOREST IN JAMBU BONGKOK,KUALA TRENGGANU,MALAYSIA

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湿地科学 2005年第3期3卷 183-189页

作者： Jumaat H Adam Nurulhuda Edy Muslim Abdul Halim Hashim Abd Rahim Othman Hafiza Abd Hamid Gire kibe Gopir Lydia M Pilik Ramlan Omar Muhammad Barzani Qasim Jumat Salimon Sahibin Abd Rahim Marlia Mohd Hanafiah School of Environmental and Natural Resource Sciences Faculty of ScienceUniversity Kebangsaan Malaysia 43600 UKM BangiSelangorMalaysia

A dichotomous key and descriptions of the species of pitcher plants recorded from bris forest at Jambu Bongkok is *** species of pitcher plants were recognized from the study *** are Nepenthes rafflesiana,Nepenthes gracilis and Nepenthes *** species can easily be identified by their morphological *** gracilis differed from the other two species in having triangular stem,sessile leaves,winged leaf base,under lid surface of the pitcher sparsely covered with honey glands,inner pitcher cavity wall covered exposed digestive glands and very narrow peristome with the thickness of≤1 *** the other hand,Nepenthes rafflesiana and Nepenthes mirabilis have cylindrical stem,stalked leaves,semi-amplexicaul leaf base,under lid surface densely covered with honey glands,inner pitcher cavity wall covered with overarched digestive glands and broad peristome with a thickness of≥1 *** rafflesiana can be differentiated from Nepenthes mirabilis by its infundibulate upper pitcher,ellipsoidal lower pitcher,inner pitcher wall cavity wholly covered with digestive glands whereas Nepenthes mirabilis have tublose-ventricose upper and lower pitchers,inner pitcher cavity wall of both pitchers partly covered with digestive glands.

关键词： Nepenthes dichotomous key and taxonomy species tropic