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Metabolic integration during the evolutionary origin of mitochondria

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cell Research 2003年第4期13卷 229-238页

作者： dennis G SEARcY Biology Department University of Massachusetts Amherst MA 01003-9297 USA

Although mitochondria provide eukaryotic cells with certain metabolic advantages, in other ways they may be disadvantageous. For example, mitochondria produce reactive oxygen species that damage both nucleocytoplasm and mitochondria, resulting in mutations, diseases, and aging. The relationship of mitochondria to the cytoplasm is best understood in the context of evolutionary history. Although it is clear that mitochondria evolved from symbiotic bacteria, the exact nature of the initial symbiosis is a matter of continuing debate. The exchange of nutrients between host and symbiont may have differed from that between the cytoplasm and mitochondria in modern cells. Speculations about the initial relationships include the following. (1) The pre-mitochondrion may have been an invasive, parasitic bacterium. The host did not benefit. (2) The relationship was a nutritional syntrophy based upon transfer of organic acids from host to symbiont. (3) The relationship was a syntrophy based upon H2 transfer from symb

关键词： mitochondria (origin) symbiosis sulfur rickettsia hydrogenosome.

Routing with cooperative Nodes Using Improved learning Approaches

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Intelligent Automation & Soft computing 2023年第3期35卷 2857-2874页

作者： R.Raja N.Satheesh J.Britto dennis c.Raghavendra Department of cSIT CVR College of EngineeringTelanganaIndia Department of computer Science and Engineering St.Martin’s Engineering CollegeSecunderabadTelanganaIndia Department of computer Science and Engineering Dhanalakshmi Srinivasan UniversityTrichyTamilnaduIndia cSIT Department CVR College of EngineeringHyderabadIndia

In IoT,routing among the cooperative nodes plays an incredible role in fulﬁlling the network requirements and enhancing system *** eva-luation of optimal routing and related routing parameters over the deployed net-work environment is *** research concentrates on modelling a memory-based routing model with Stacked long Short Term Memory(s-lSTM)and Bi-directional long Short Term Memory(b-lSTM).It is used to hold the routing information and random routing to attain superior *** pro-posed model is trained based on the searching and detection mechanisms to com-pute the packet delivery ratio(PDR),end-to-end(E2E)delay,throughput,*** anticipated s-lSTM and b-lSTM model intends to ensure Quality of Service(QoS)even in changing network *** performance of the proposed b-lSTM and s-lSTM is measured by comparing the signiﬁcance of the model with various prevailing ***,the performance is measured with Mean Absolute Error(MAE)and Root Mean Square Error(RMSE)for mea-suring the error rate of the *** prediction of error rate is made with learn-ing-based Stochastic Gradient Descent(l-SGD).This gradual gradient descent intends to predict the maximal or minimal error through successive *** simulation is performed in a MATlAB 2020a environment,and the model performance is evaluated with diverse *** anticipated model intends to give superior performance in contrast to prevailing approaches.

关键词： Internet of Things(IoT) stacked long short term memory bi-directional long short term memory error rate stochastic gradient descent

Accelerated oxidation of VOcs via vacuum ultraviolet photolysis coupled with wet scrubbing process

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Journal of Environmental Sciences 2023年第12期134卷 55-64页

作者： Ruijie Xie Dongxue lei Xiaowen Xie Ziyi Suo dennis Y.c.leung Jianping cao Fang Ruimei Haibao Huang School of Environmental Science and Engineering Sun Yat-sen UniversityGuangzhou 510275China Department of Mechanical Engineering University of Hong KongHong Kong 999077China college of Environment and Resources Chongqing Technology and Business UniversityChongqing 400067China Scientific Research Academy of GuangXi Environmental Protection Nanning 530022China

Vacuum ultraviolet(VUV) photolysis is a facile method for volatile organic compounds(VOcs) elimination, but is greatly limited by the relatively low removal efficiency and the possible secondary pollution. To overcome above drawbacks, we developed an efficient method for VOcs elimination via VUV photolysis coupled with wet scrubbing process. In this coupled process, volatile toluene, a representative of VOcs, was oxidized by the gas-phase VUV photolysis, and then scrubbed into water for further oxidation by the liquid-phase VUV photolysis. More than 96% of toluene was efficiently removed by this coupled process, which was 2 times higher than that in the gas-phase VUV photolysis. This improvement was attributed to the synergistic effect between gas-phase and liquid-phase VUV photolysis. O3and HO·are the predomination reactive species for the toluene degradation in this coupled process, and the generation of O3in gas-phase VUV photolysis can efficiently enhance the HO·production in liquid-phase VUV photolysis. The result from in-situ proton transfer reaction ionization with mass analyzer(PTR-MS) further suggested that most intermediates were trapped by the wet scrubbing process and efficiently oxidized by the liquid-phase VUV photolysis, showing a high performance for controlling the secondary pollution. Furthermore, the result of stability test and the reuse of solution demonstrated that this coupled process has a highly stable and sustainable performance for toluene degradation. This study presents an environmentally benign and highly efficient VUV photolysis for gaseous VOcs removal in the wet scrubbing process.

关键词： Volatile organic compounds(VOcs) Vacuum ultraviolet(VUV)photolysis Wet scrubbing process Toluene degradation Intermediates analysis

Dolichocolon revisited: An inborn anatomic variant with redundancies causing constipation and volvulus

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World Journal of Gastrointestinal Surgery 2018年第2期10卷 6-12页

作者： dennis Raahave Department of Surgery Copenhagen University North Sealand Hospital

The objective of this review is to examine whether a redundant colon gives rise to symptoms like constipation and volvulus. In 1820, Monterossi made drawings of colons with displacements and elongation of the colon found during autopsy. In 1912, Kienb?eck first visualized a redundant colon using bismuth, and lardennois and Auborg named the anatomic variant dolichocolon in 1914. The criteria were later: A sigmoid loop rising over the line between the iliac crests, a transverse colon below the same line and extra loops at the flexures. The incidence of dolichocolon is 1.9%-28.5%. Dolichocolon seems to be congenital, as fetuses, newborns, and infants exhibit colonic redundancies. Studies have identified a triade of constipation, abdominal pain, and distension. colon transit time was recently shown to increase significantly with increased number of redundancies, which increases abdominal pain, bloating and infrequent defecation. The diagnosis of dolichocolon is established by barium enema or cT-colonography. Treatment is conservative, or surgical in case of volvulus or refractory constipation.

关键词： Dolichocolon colon elongatum Functional gastrointestinal disorders constipation Volvulus

UV light-induced oxygen doping in graphitic carbon nitride with suppressed deep trapping for enhancement in cO_(2) photoreduction activity

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Journal of Materials Science & Technology 2023年第2期133卷 135-144页

作者： Xiaolong Zhao Xiaoping Yi Wending Pan Yifei Wang Shijing luo Yingguang Zhang Ruijie Xie dennis Y.c.leung Department of Mechanical Engineering the University of Hong KongPokfulam RoadHong KongChina School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China School of Mechanical Engineering and Automation Harbin Institute of TechnologyShenzhen 518055China

While photoreduction of cO_(2) to cH 4 is an effective means of producing value-added fuels,common pho-tocatalysts have poor activity and low selectivity in photocatalytic cO_(2)-reduction *** though creating defects is an effective photocatalyst fabrication route to improve photocatalytic activity,there are some challenges with the facile photocatalyst synthesis *** this work,an O element is in-troduced into a graphitic carbon nitride(cN)skeleton through a precursory ultraviolet light irradiation pretreatment to increase the visible light absorption and enhance the carrier density of this modified non-metal cN photocatalyst;the charge transfer dynamics thereof are also studied through electrochem-ical tests,photoluminescence spectroscopy,and nanosecond transient *** verify that the op-timized sample exhibits lower charge recombination and a suppressed 84 ns electron-trapping lifetime,compared to the 103 ns electron-trapping lifetime of the cN counterpart,and thereby contributes to ro-bust detrapping and a fast transfer of active *** density functional theory calculations,we find that the improved light absorption and increased electron density are ascribed to O-element doping,which enhances the cO_(2) adsorption energy and improves the cO_(2)-to-cH 4 photoreduction activity;it be-comes 17 times higher than that of the bare cN,and the selectivity is 3.8 times higher than that of ***,the optimized sample demonstrates excellent cyclic stability in a 24-hour cycle test.

关键词： UV light Oxygen doping charge transfer Graphitic carbon nitride cO_(2)reduction

Guardians of the eye:new tales about retinal microglia and other ocular macrophages

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Neural Regeneration Research 2022年第6期17卷 1275-1277页

作者： dennis-Dominik Rosmus Peter Wieghofer Institute of Anatomy Leipzig UniversityLeipzigGermany

Macrophages are highly versatile and plastic immune cells that are localized in nearly all organs of the body and contribute to a plethora of physiological and pathological processes in *** their roles as major players in the“first line of defense”under inflammatory conditions,macrophages are known to participate in tissue homeostasis maintenance.

关键词： organs homeostasis ocular

Ultraviolet discharges from a radio-frequency system for potential biological/chemical applications

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chinese Physics B 2017年第8期26卷 157-161页

作者： Joseph Ametepe Sheng Peng dennis Manos Georgia Gwinnett college School of Science and TechnologyLawrenceville-GA 30078USA EXFO Mississaugaon Canada L5N 6H7 college of William and Mary Department of PhysicsWilliamsburgVA 2385USA

In this work, we describe a new electrode-less radio-frequency（RF） excitation technique for generating excimers in the vacuum ultraviolet（VUV） and ultraviolet（UV） spectral regions for potential biological/chemical applications. Spectra data of Xe~＊_2, XeI~＊, and KrI~＊ generated by this new technique are presented. Optical efficiency of the lamp system ranges from 3% to 6% for KrI~＊, 7% to 13% for XeI~＊, and 15% to 20% for Xe~＊_2. Also, results of irradiating E-coli with XeI~＊discharge from this lamp system is presented to show one of the promising applications of such electrode-less *** new RF lamp system offers an interesting addition to the already existing technologies for generating VUV and UV light for various biological, physical, and chemical processes especially those requiring large area for high productivity.

关键词： radio-frequency ultraviolet light Xe2* XeI* KrI* excimers escherichia coli

Performance evaluation of a water erosion tracer using plot-scale experiments and process-based modeling

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International Soil and Water conservation Research 2023年第4期11卷 622-632页

作者： João M.Villela Jamil A.A.Anache Alex M.Watanabe dennis c.Flanagan Edson c.Wendland Silvio crestana EMBRAPA-Brazilian Agricultural Research corporation LNNA-National Laboratory of Nanotechnology for AgrobusinessSt.XV de NovembroSão CarlosSP13560-970Brazil University of São Paulo(USP) São Carlos School of Engineering.Graduate Program in Environmental Engineering Sciences(PPG-SEA)Av.Trabalhador São-CarlenseCxP.359São CarlosSP13566590Brazil Department of Hydraulics and Sanitation São Carlos School of Engineering(EESC)University of São Paulo(USP)CxP.359São CarlosSP13566-590Brazil Federal University of Mato Grosso Do Sul CxP.549Campo Grande.MS.79070-900Brazil USDA-Agricultural Research Service National Soil Erosion Research Laboratory275 S.Russell StWest LafayetteIN47907USA

Socioeconomic and environmental losses caused by water erosion have highlighted the importance of quantifying and understanding the dynamics of soil redistribution in the landscape to develop effective soil management *** methods are applied to estimate erosion/deposition rates and identify sources of sediments,among them,the one that uses rare earth elements(REE)as a tracer stands ***,an alternative not yet explored that can benefit the accuracy of the estimates provided by the method is using a tracer containing a chemical signature composed of more than one *** present study aimed to evaluate the performance of a new water erosion tracer based on montmoril-lonite labeled with rare earth elements(la40-MMT).The innovative aspects of this la40-MMT tracer include its highly stable multi-chemical signature(Nd^(3+),la^(3+),and Pr^(3+)),which enhances tracer detection in the environment,and its low production cost due to the use of an industrial residue in the synthesis *** tracer was evaluated for a typical soil of the cerrado biome,using a natural rainfall field-scale plot-NRFP(5 m × 20 m)and a physical predictive erosion model(WEPP).The results showed that the la40-MMT tracer could be used to estimate erosion/deposition rates,with agreement between the values observed with the tracer and the WEPP ***,this study confirmed the great potential of la40-MMT as a tool to identify patterns of soil redistribution at the field scale and aid in the validation of erosion models.

关键词： Soil erosion Tracer Rare earth elements Deposition Sediment source WEPP Model

The Study of Deposition Parameters, Properties for PVD Ti_xN and cr_xN coatings Using a closed Field Unbalanced Magnetron Sputter Ion Plating System

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材料热处理学报 2004年第5B期25卷 841-846页

作者： HailinSun SusanField Jianchen dennis.G.Teer Teercoatingsltd. WestStoneHouseBerryHillIndustrialEstateDroitwichWR99ASUK StateKeylaboratoryofMechanicalBehaviourforMaterialss Xi＇anJiaotongUniversityP.R.CHINA

closed Field Unbalanced Magnetron Sputter Ion Plating (cFUBMSIP) systems have been used increasingly for PVD coating in recent years. TiN and crN coatings, commonly used as the basic coating for a number of different hard coatings, have been chosen to study the coating process parameters for the cFUBMSIP system. In this paper, the process parameters, such as substrate temperature, substrate bias and OEM control, have been carefully examined to achieve hard and wear-resistance coatings with good adhesion. The coating structure and orientation were found to change according to the coating parameters. The Rockwell test and Scratch test were carried out to examine the coating adhesion; pin-on-disc testing was used to estimate the wear-resistant; micro-hardness was also used to determine coating hardness. HSS drill testing has been carried out to study the general properties of the coating for cutting tool application. A combination of process parameters can be selected to achieve good performance for the TiN and crN coatings.

关键词： PVD 衬底温度磁控管溅射 TixN涂层 crxN涂层 OEM