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Effects of mountain pine beetle-killed forests on source water contributions to streamflow in headwater streams of the Colorado Rocky Mountains

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Frontiers of Earth Science 2017年第3期11卷 496-504页

作者： Christine E. WEHNER john d. STEdNICK Watershed Science Program College of Natural Resources Colorado State University Fort Collins CO 80523-1472 USA

Natural or human-influenced disturbances are important to the health and diversity of forests, which in turn, are important to the water quantity and quality exported from a catchment. However, human-induced disturbances （prescribed fire and harvesting） have been decreasing, and natural disturbances （fires and insects） have been increasing in frequency and severity. One such natural disturbance is the mountain pine beetle （MPB）, （denclroctonus ponderosae） an endemic species. A recent epidemic resulted in the mortality of millions of hectares of lodgepole pine （Pinus contorta） forests in Colorado, USA. Beetle-induced tree mortality brings about changes to the hydrologic cycle, including decreased transpiration and interception with the loss of canopy cover. This study examined the effect of the mountain pine beetle kill on source water contributions to streamflow in snowmelt- dominated headwater catchments using stable isotopes （2H and ~80） as tracers. Study catchments with varying level of beetle-killed forest area （6% to 97%） were sampled for groundwater, surface water, and precipitation. Streams were sampled to assess whether beetle-killed forests have altered source water contributions to streamflow. Ground- water contributions increased with increasing beetle-killed forest area （p = 0.008）. Both rain and snow contributions were negatively correlated with beetle-killed forest area （p = 0.035 and p = 0.011, respectively）. As the beetle-killed forest area increases, so does fractional groundwater contribution to streamflow.

关键词： mountain pine beetle isotope tracers stream-flow generation headwaters

Glucose metabolism in amyotrophic lateral sclerosis:it is bitter-sweet

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Neural Regeneration Research 2022年第9期17卷 1975-1977页

作者： Titaya Lerskiatiphanich Jianina Marallag john d.Lee School of Biomedical Sciences Faculty of MedicineThe University of QueenslandSt LuciaBrisbaneQLDAustralia

A recent study by Mcdonald et al.(2021)focused on how peripheral glucose metabolism and handling are compromised in amyotrophic lateral sclerosis(ALS).dysfunctions in glucose and energy metabolism have been identified in transgenic mouse models and patients with ***,how these processes are altered and contribute to disease progression are not fully *** aforementioned study has identified several changes to glucose homeostasis in the transgenic SOd1G93A mouse model of ALS at the later stages of the ***,the authors found that despite insulin resistance being present,there was increased glucose uptake in ALS mice,and increased glycogen accumulation in the ***,there was evidence of glucagon resistance developing in these mice,which supports clinical *** perspective outlines the key aspects of glucose metabolism and demonstrates how multiple pathways relating to these processes are compromised in ALS.

关键词： metabolism amyotrophic homeostasis

Complement:a global immunometabolic regulator in amyotrophic lateral sclerosis

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Neural Regeneration Research 2021年第6期16卷 1210-1211页

作者： Martin W.Lo john d.Lee School of Biomedical Sciences Faculty of MedicineThe University of QueenslandSt LuciaQueenslandAustralia

Recently,Mcdonald et al.(2020)proposed that complement causes a metabolic switch to lipid consumption in amyotrophic lateral sclerosis(ALS),which raises the possibility of complement as a global immunometabolic *** ALS,neuromuscular degeneration occurs concurrently with complement-mediated inflammation,glucose intolerance,and elevated lipid ***,complement is being increasingly recognized as a metabolic regulator that can induce insulin resistance and alter fuel source ***,the authors propose that chronic complement activation may be driving metabolic reprogramming in ALS,which has broad implications for the field of immunometabolism and would be the first mechanistic explanation of the“lipid switch”in ***,it suggests that complement can drive a global shift in resources during inflammation,in which glucose is redirected from peripheral tissues to immune cells to support their inflammatory actions.

关键词： inflammation metabolism elevated

Proportional-integral-derivative control of nonlinear half-car electro-hydraulic suspension systems

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浙江大学学报（英文版）A辑：应用物理与工程 2013年第6期14卷 401-416页

作者： john E. d. EKORU Jimoh O. PEdRO School of Mechanical Aeronautical and Industrial Engineering University of the Witwatersrand Private Bag 03 WITS 2050 Johannesburg South Africa

This paper presents the development of a proportional-integral-derivative (PId)-based control method for application to active vehicle suspension systems (AVSS). This method uses an inner PId hydraulic actuator force control loop, in combination with an outer PId suspension travel control loop, to control a nonlinear half-car AVSS. Robustness to model uncertainty in the form of variation in suspension damping is tested, comparing performance of the AVSS with a passive vehicle suspension system (PVSS), with similar model parameters. Spectral analysis of suspension system model output data, obtained by performing a road input disturbance frequency sweep, provides frequency response plots for both nonlinear vehicle suspension systems and time domain vehicle responses to a sinusoidal road input disturbance on a smooth road. The results show the greater robustness of the AVSS over the PVSS to parametric uncertainty in the frequency and time domains.

关键词： Force control Proportional-integral-derivative (PId) control Nonlinear half-car Active vehicle suspension system (AVSS) Hydraulic actuator dynamics Model uncertainty

陆生蜗牛壳体日分辨率氧同位记录定量重建"千年一遇"超级暴雨

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Science Bulletin 2024年第14期69卷 2281-2288页

作者：王国桢董吉宝韩韬刘成程罗凡杨昊天何妙宏唐国强赵楠钰张倩薛刚 john dodson 李秋立晏宏 State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China Laoshan Laboratory Qingdao 266061China Institute of Global Environmental Change Xi’an Jiaotong UniversityXi’an 710049China National Observation and Research Station of Earth Critical Zone on the Loess Plateau of Shaanxi Xi’an 710061China Xi’an Institute for Innovative Earth Environment Research Xi’an 710061China State Key Laboratory of Isotope Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China School of Biological Earth and Environmental SciencesUniversity of New South WalesSydney 2052Australia State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Yunnan Key Laboratory of Earth System Science Yunnan UniversityKunming 650500China University of Chinese Academy of Sciences Beijing 100049China

A"once-in-a-millennium"super rainstorm battered Zhengzhou,central China,from 07/17/2021 to 07/22/2021(named"7.20"Zhengzhou rainstorm).It killed 398 people and caused billions of dollars in damage.A pressing question is whether rainstorms of this intensity can be effectively documented by geological archives to understand better their historical variabilities beyond the range of meteorological ***,four land snail shells were collected from Zhengzhou,and weekly to daily resolved snail shellδ^(18)O records from June to September of 2021 were obtained by gas-source mass spectrometry and secondary ion mass *** daily resolved records show a dramatic negative shift between 06/18/2021 and 09/18/2021,which has been attributed to the"7.20"Zhengzhou ***,the measured amplitude of this shift is consistent with the theoretical value estimated from the flux balance model and instrumental data for the"7.20"Zhengzhou *** results suggest that the ultra-high resolutionδ^(18)O of land snail shells have the potential to reconstruct local synoptic scale rainstorms quantitatively,and thus fossil snail shells in sedimentary strata can be valuable material for investigating the historical variability of local rainstorms under different climate backgrounds.

关键词： Rainstorm Land snail shell d18O Paleoweather Central China

Characterization of the Tomato Prosystemin Promoter:Organ-specific Expression,Hormone Specificity and Methyl Jasmonate Responsiveness by deletion Analysis in Transgenic Tobacco Plants

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Journal of Integrative Plant Biology 2012年第1期54卷 15-32页

作者： Hamlet Avilés-Arnaut john Paul délano-Frier Center of Research and Advanced Studies (Cinvestav) at Irapuato:Unit for Plant Biotechnology and Genetic Engineering

Tomato systemin is a bioactive peptide that regulates the systemic activation of wound-responsive genes. It is released from its 200 amino acid precursor called prosystemin. Initial tissue-localization and hormone-induced expression assays indicated that the tomato prosystemin gene （SIPS） accumulates mainly in floral tissues and in response to exogenous abscisic acid and methyl jasmonate （MeJA） treatments, respectively. Later, the promoter regions of the PS gene in tomato （Solanum lycopersicum L. cv. Castlemart）, pepper （Capsicum annuum） and potato （Solanum tuberosum） were isolated and an in silico analysis of the SIPS promoter revealed an over-representation of stress- and MeJA-responsive motifs. A subsequent 5＇ deletion analysis of the SIPS promoter fused to the/^-glucuronidase reporter （GUS） gene showed that the -221 to ＋40 bp proximal SIPS promoter region was sufficient to direct the stigma, vascular bundle-specific and MeJA-responsive expression of GUS in transgenic tobacco plants. Important ***-specific, light- and MeJA-responsive cis-elements were also present in this region. These findings provide relevant information regarding the transcriptional regulation mechanisms of the SIPS promoter operating in transgenic tobacco plants. They also suggest that its Ussue-specificity and inducible nature could have wide applicability in plant biotechnology.

关键词： cis-regulatory elements flower specific jasmonic acid methyl jasmonate promoter analysis prosystemin wound-responsive genes.

Epidemiological, diagnostic, Therapeutic and Progressive Aspects of Arterial Hypertension in Children at the University Hospital Center of Bouaké (Côte d’Ivoire)

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Open Journal of Pediatrics 2024年第2期14卷 379-390页

作者： Richard Azagoh-Kouadio Yao Kossonou Roland Yeboua Kouassi Christian Yao john Patrick Yenan Iburaima Alamun Akanji Kouadio Vincent Assé Pediatric department of Angré University Hospital Abidjan Ivory Coast Pediatric department of Bouaké University Hospital Bouaké Ivory Coast

Introduction: Arterial hypertension (AH) in children is under-diagnosed and often has a poor prognosis. The aim of this study was to describe the epidemiological, diagnostic, therapeutic and evolutionary aspects of hypertension in children at the University Hospital of Bouaké, with a view to improving the prognosis. Methods: This was a cross-sectional, analytical study carried out in the paediatrics department of Bouaké University Hospital. It concerned the medical records of children aged 4 to 15 hospitalised from 1 January 2017 to 31 december 2020 for hypertension. diagnosis was based on the simplified blood pressure guidelines of the Expert Consensus of the French Society of Hypertension. The variables studied were epidemiological, diagnostic, therapeutic and evolutionary. Quantitative variables were compared at the significance level p ≤ 0.05. Results: The hospital incidence of hypertension was 0.32% (69/21,642). The sex ratio was 0.72. 97.1% of the children were over five years of age. Oedema (49.3%) and breathing difficulties (20.2%) were the main reasons for consultation. Hypertension was classified as threatening (56.5%), confirmed (31.9%) and borderline (11.6%). The cause was renal in 66.7%, dominated by impure nephrotic syndrome (24.6%). Treatment for hypertension consisted mainly of a diuretic (79.7%) and a calcium channel blocker (47.8%). Outcome was favourable in 50.7% of cases. Mortality was 20.3%. No factor was significantly associated with death. Conclusion: Hypertension in children at Bouaké University Hospital is serious. The aetiology is mainly renal. Early diagnosis and management are key to improving prognosis.

关键词： Hypertension Children Renal Pathologies Prognosis Côte d’Ivoire

Structural effects induced by dialysis-based purification of carbon nanomaterials

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Nano Materials Science 2024年第4期6卷 475-483页

作者： A.d.Veloso A.M.Ferraria A.M.Botelho do Rego A.S.Viana A.J.S.Fernandes A.J.Fielding R.A.Videira M.C.Oliveira CQ-VR and Chemistry department University of Trás-os-Montes e Alto Douro BSIRG iBB-Institute for Bioengineering and BiosciencesDepartment of Chemical Engineeringand Associate Laboratory i4HB-Institute for Health and BioeconomyInstituto Superior TécnicoUniversidade de Lisboa Centro de Química Estrutural Institute of Molecular SciencesDepartamento de Química e BioquímicaFaculdade de CiênciasUniversidade de Lisboa I3N and Physics department University of AveiroCampus de Santiago Faculty of Science Pharmacy and Biomolecular SchoolLiverpool John Moores University REQUIMTE/LAQV Laborat orio de FarmacognosiaDepartamento de QuímicaFaculdade de Farm aciaUniversidade do Porto

dialysis plays a crucial role in the purification of nanomaterials but its impact on the structural properties of carbon nanomaterials was never ***,a carbon-based nanomaterial generated electrochemically in potassium phosphate buffer,was characterized before and after dialysis against pure *** is shown that dialysis affects the size of the carbon domains,structural organization,surface functionalization,oxidation degree of carbon,and grade of ***,dialysis drives the nanomaterial organization from discrete roundish carbon domains,with sizes ranging from 70 to 160 nm,towards linear stacking structures of small nanoparticles （d ether （epoxide） surface groups evolve into more oxidized carbon groups （e.g.,ketone and ester groups）.Investigation of the as-prepared nanomaterial by electron paramagnetic resonance （EPR） revealed a resonance signal consistent with carbon-oxygen centred ***,this study brings to light the selective affinity of the carbon nanomaterial under study to capture Na+ions,a property greatly enhanced by the dialysis process,and its high ability to trap oxygen,particularly before *** findings open new perspectives for the application of carbon-based nanomaterials and raise awareness of the importance of structural changes that can occur during the purification of carbon-based nanomaterials.

关键词： Nanocarbon Surface functionalization NMR XPS Hydrophilic carbon Paramagnetic

Secure data networks for electrical distribution applications

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Journal of Modern Power Systems and Clean Energy 2015年第3期3卷 447-455页

作者： david M.LAVERTY john B.O’RAW Kang LI d.john MORROW School of EEECS Queen’s University Belfast125 Stransmillis RoadBelfast BT95AHUK

Smart Grids are characterized by the application of information communication technology(ICT)to solve electrical energy *** power networks span large geographical areas,thus a necessary component of many Smart Grid applications is a wide area network(WAN).For the Smart Grid to be successful,utilities must be confident that the communications infrastructure is *** paper describes how a WAN can be deployed using WiMAX radio technology to provide high bandwidth communications to areas not commonly served by utility communications,such as generators embedded in the distribution network.A planning exercise is described,using Northern Ireland as a case *** suitability of the technology for real-time applications is assessed using experimentally obtained latency data.

关键词： Telecoms Latency WiMAX Security