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Observation of ocean current response to 1998 Hurricane Georges in the Gulf of Mexico

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Acta Oceanologica Sinica 2006年第1期25卷 1-14页

作者： ZHENG Quanan LAI Ronald j HUANG Nortlen E PAN jiayi LIU W timothy Department of Atmospheric and Oceanic Science University of Maryland College Park Maryland 20742 USA Minerals Management Service U S Department of the Interior Hemdon Virginia 20170 USA Ocean and Ice Branch NASA Goddard Space Flight Center Greenbelt Maryland 20771 USA Department of Environmental and Biomolecular Systems Oregon Graduate Institute Beaverton Oregon 97006 USA jet Propulsion Laboratory California Institute of Technology Pasadena California 91109 USA

The ocean current response to a hurricane on the shelf-break is examined. The study area is the DeSoto Canyon in the northeast Gulf of Mexico, and the event is the passage of 1998 Hurricane Georges with a maximum wind speed of 49 m/s. The data sets used for analysis consist of the mooring data taken by the Field Program of the DeSoto Canyon Eddy Intrusion Study, and simultaneous winds observed by NOAA （National Oceanic and Atmospheric Administration） Moored Buoy 42040. Time-depth ocean current energy density images derived from the observed data show that the ocean currents respond almost immediately to the hurricane with important differences on and offthe shelf. On the shelf, in the shallow water of 100 m, the disturbance penetrates rapidly downward to the bottom and forms two energy peaks, the major peak is located in the mixed layer and the secondary one in the lower layer. The response dissipates quickly after external forcing disappears. Offthe shelf, in the deep water, the major disturbance energy seems to be trapped in the mixed layer with a trailing oscillation; although the disturbance signals may still be observed at the depths of 500 and 1 290 m. Vertical dispersion analysis reveals that the near-initial wave packet generated offthe shelf consists of two modes. One is a barotropic wave mode characterized by a fast decay rate of velocity amplitude of 0.020 s^-, and the other is baroclinic wave mode characterized by a slow decay rate of 0.006 9 s^-1. The band-pass-filtering and empirical function techniques are employed to the frequency analysis. The results indicate that ialf frequencies shift above the local inertial frequency. On the shelf, the average frequency is 1.04fin the mixed layer, close to the diagnosed frequency of the first baroclinic mode, and the average frequency increases to 1.07fin the thermocline. Offthe shelf, all frequencies are a little smaller than the diagnosed frequency of the first mode. The average frequency decreases from 1.035

关键词： shelf dynamics hurricane ocean current air-sea interaction

Net ecosystem carbon exchange for Bermuda grass growing in mesocosms as affected by irrigation frequency

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Pedosphere 2022年第3期32卷 393-401页

作者： Yuan LI Gabriel *** timothy j.CLOUGH john E.HUNT David WHITEHEAD Department of Soil and Physical Sciences Lincoln UniversityLincoln 7647(New Zealand) Manaaki Whenua-Landcare Research P.O.Box 69040Lincoln 7640(New Zealand) State Key Laboratory of Grassland Agro-ecosystems College of Pastoral Agriculture Science and TechnologyLanzhou UniversityLanzhou 730020(China) Soil Biology Group Wageningen University and ResearchP.O.Box 47Wageningen 6700 AA(The Netherlands)

Intensification of grazed grasslands following conversion from dryland to irrigated farming has the potential to alter ecosystem carbon(C)cycling and affect components of carbon dioxide(CO_(2))exchange that could lead to either net accumulation or loss of soil *** there are many studies on the effect of water availability on biomass production and soil C stocks,much less is known about the effect of the frequency of water inputs on the components of CO_(2)*** grew Bermuda grass(Cynodon dactylon L.)in mesocosms under irrigation frequencies of every day(I_(1) treatment,30 d),every two days(I_(2) treatment,12 d),every three days(I_(3) treatment,30 d),and every six days(I_(6) treatment,18 d,after I_(2) treatment).Rates of CO_(2)exchange for estimating net ecosystem CO_(2)exchange(F_(N)),ecosystem respiration(R_(E)),and soil respiration(R_(S))were measured,and gross C uptake by plants(F_(G))and respiration from leaves(R_(L))were calculated during two periods,1–12 and 13–30 d,of the 30-d *** the first 12 d,there were no significant differences in cumulative F_(N)(mean±standard deviation,61±30 g C m^(-2),n=4).During the subsequent 18 d,cumulative F_(N) decreased with decreasing irrigation frequency and increasing cumulative soil water deficit(W),with values of 70±22,60±16,and 18±12 g C m^(-2) for the I_(1),I_(3),and I_(6) treatments,*** were similar decreases in F_(G),R_(E),and R_(L) with increasing W,but differences in R_(S) were not *** of the C_(4) grass growing in a C_(3)-derived soil enabled partitioning of R_(S) into its autotrophic(R_(A))and heterotrophic(R_(H))components using a^(13)C natural abundance isotopic technique at the end of the experiment when differences in cumulative W between the treatments were the *** values of R_(H) and its percentage contributions to R_(S)(43%±8%,42%±8%,and 8%±5%for the I_(1),I_(3),and I_(6) treatments,respectively)suggested that R_(H) remained unaffected across a wide

关键词： ^(13)C natural abundance CO_(2)exchange N_(2)O emission soil heterotrophic respiration water deficit

Irritable bowel syndrome: A microbiome-gut-brain axis disorder?

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World journal of Gastroenterology 2014年第39期20卷 14105-14125页

作者： Paul j Kennedy john F Cryan timothy G Dinan Gerard Clarke 1.15 Biosciences Institute Department of Psychiatry Alimentary Pharmabiotic Centre University College Cork Cork Ireland Department of Anatomy and Neuroscience Alimentary Pharmabiotic CentreUniversity College CorkCork Ireland

Irritable bowel syndrome(IBS) is an extremely prevalent but poorly understood gastrointestinal disorder. Consequently, there are no clear diagnostic markers to help diagnose the disorder and treatment options are limited to management of the symptoms. The concept of a dysregulated gut-brain axis has been adopted as a suitable model for the disorder. The gut microbiome may play an important role in the onset and exacerbation of symptoms in the disorder and has been extensively studied in this context. Although a causal role cannot yet be inferred from the clinical studies which have attempted to characterise the gut microbiota in IBS, they do confirm alterations in both community stability and diversity. Moreover, it has been reliably demonstrated that manipulation of the microbiota can influence the key symptoms, including abdominal pain and bowel habit, and other prominent features of IBS. A variety of strategies have been taken to study these interactions, including probiotics, antibiotics, faecal transplantations and the use of germ-free animals. There are clear mechanisms through which the microbiota can produce these effects, both humoral and neural. Taken together, these findings firmly establish the microbiota as a critical node in the gut-brain axis and one which is amenable to therapeutic interventions.

关键词： Irritable bowel syndrome Microbiome Anxiety Tryptophan Abdominal pain Gastrointestinal motility Cognition

Spatial targeting evaluation of energy and environmental performance of waste-to-energy processing

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Frontiers of Chemical Science and Engineering 2018年第4期12卷 731-744页

作者： Petar S.Varbanov timothy G.Walmsley Yee V.Fan jiri j.Klemes Simon j.Perry Sustainable Process Integration Laboratory NETME CentreFaculty of Mechanical EngineeringBmo University of Technology61669 Bmo Czech Republic Centre for Process Integration School of Chemical Engineering and Analytical ScienceThe University of ManchesterManchester M I 3ALUK

Waste-to-energy supply chains are important potential contributors to minimising the environmental impacts of municipal solid waste by reducing the amounts of waste sent to landfill, as well as the fossil fuel consumption and environmental footprints. Accounting for the spatial and transport properties of the waste-to-energy supply chains is crucial for understanding the problem and improving the supply chain designs. The most significant challenge is the distributed nature of the waste generation and the household energy demands. The current work proposes concepts and a procedure for targeting the size of the municipal solid waste collection zone as the first step in the waste-to-energy supply chains synthesis. The formulated concepts and the provided case study reveal trends of reducing the net greenhouse gas savings and energy recovery by increasing the collection zone size. Population density has a positive correlation with the greenhouse gas saving and energy recovery performance. For smaller zone size the energy recovery from waste approaches and in some cases may surpass the energy spent on waste transportation. The energy recovery and greenhouse gas savings remain significant even for collection zones as large as 200 km2. The obtained trends are discussed and key directions for future work are proposed.

关键词： waste-to-energy supply chain optimisation GHG savings energy recovery ratio

Automated retrofit targeting of heat exchanger networks

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Frontiers of Chemical Science and Engineering 2018年第4期12卷 630-642页

作者： timothy G.Walmsley Nathan S.Lal Petar S.Varbanov jiri j.Klemes Sustainable Process Integration Laboratory -SPIL NETME CentreFaculty of Mechanical Engineering Bmo University of TechnologyBmo 60190Czech Republic Energy Research Centre School of EngineeringUniversity of WaikatoHamilton 3240New Zealand

The aim of this paper is to develop a novel heat exchanger network (HEN) retrofit method based on a new automated retrofit targeting (ART) algorithm. ART uses the heat surplus-deficit table (HSDT) in combination with the Bridge Retrofit concepts to generate retrofit bridges option, from which a retrofit design may be formulated. The HSDT is a tabular tool that shows potential for improved re-integration of heat source and sink streams within a HEN. Using the HSDT, retrofit bridges—a set of modifications that links a cooler to a heater to save energy—may be identified, quantified, and compared. The novel retrofit method including the ART algorithm has been successfully implemented in Microsoft ExcelTM to enable analysis of large-scale HENs. A refinery case study with 27 streams and 46 existing heat exchangers demonstrated the retrofit method’s potential. For the case study, the ART algorithm found 68903 feasible unique retrofit opportunities with a minimum 400 kW·unit−1 threshold for heat recovery divided by the number of new units. The most promising retrofit project required 3 new heat exchanger units to achieve a heat savings of 4.24 MW with a favorable annualised profit and a reasonable payback period.

关键词： process retrofit pinch analysis heat exchanger network heat recovery

Cardiac rehabilitation and exercise therapy in the elderly： Should we invest in the aged？

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journal of Geriatric Cardiology 2012年第1期9卷 68-75页

作者： Arthur R Menezes Carl j Lavie Richard V Milani Ross A Arena timothy S Church Department of Cardiovascular Diseases John Ochsner Heart and Vascular Institute Ochsner Clinical School The University of Queensland School ofMedicine 1514 Jefferson Highway New Orleans LA 70121 USA Department of Orthopaedics Physical Therapy Program and Division of Cardiology Department of Internal Medicine University of New MexicoAlbuquerque NM87131 USA Department of Preventive Medicine Pennington Biomedical Research Center Louisiana State University System Baton Rouge LA 70808 USA

Coronary heart disease （CHD） is the leading cause of death worldwide and becomes increasingly prevalent among patients aged 65 years and *** patients are at a higher risk for complications and accelerated physical deconditioning after a cardiovascular event,especially compared to their younger *** last few decades were privy to multiple studies that demonstrated the beneficial effects of cardiac rehabilitation （CR） and exercise therapy on mortality,exercise capacity,psychological risk factors,inflammation,and obesity among patients with ***,a significant portion of the available data in this field pertains to younger patients.A viable explanation is that older patients are grossly underrepresented in these programs for multiple reasons starting with the patient and extending to the *** this article,we will review the benefits of CR programs among the elderly,as well as some of the barriers that hinder their participation.

关键词： Cardiac rehabilitation Exercise therapy Elderly patients Exercise capacity

Déjàvu:Might Future Eruptions of Hunga Tonga-Hunga Ha'apai Volcano be a Repeat of the Devastating Eruption of Santorini,Greece(1650 BC)?

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journal of Earth Science 2022年第2期33卷 229-235页

作者： timothy M.Kusky Center for Global Tectonics Three Gorges Research Center for Geo-HazardsChina University of GeosciencesWuhan 430074China

The remote Pacific islands nation of Tonga(about 170 islands,with a population of 105000),and surrounding countries,are suffering from the damage from one of the largest,most explosive volcanic eruptions in at least several decades,at least since the 1991 eruption of Pinatubo in the *** data is still coming in from the jan.15,2022 *** reports show(remarkably)few casualties,but the islands are still(as of this writing)inaccessible because of thick volcanic ash coverings。

关键词： volcanic eruption thick

Seasonal Variations of CH_4 Emissions in the Yangtze River Delta Region of China Are Driven by Agricultural Activities

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Advances in Atmospheric Sciences 2021年第9期38卷 1537-1551页

作者： Wenjing HUANG timothy jGRIFFIS Cheng HU Wei XIAO Xuhui LEE Yale-NUIST Center on Atmospheric Environment International Joint Laboratory on Climate and Environment Change(ILCEC)Nanjing University of InformationScience and TechnologyNanjing 210044China Department of Soil Waterand ClimateUniversity of MinnesotaTwin CitiesSt.PaulMN 55108USA College of Biology and the Environment Joint Center for sustainable Forestry in Southern ChinaNanjing Forestry UniversityNanjing 210037China School of the Environment Yale UniversityNew HavenCT 06511USA

Developed regions of the world represent a major atmospheric methane(CH_4) source,but these regional emissions remain poorly *** Yangtze River Delta(YRD) region of China is densely populated(about 16% of China's total population) and consists of large anthropogenic and natural CH_4 ***,atmospheric CH_4 concentrations measured at a 70-m tall tower in the YRD are combined with a scale factor Bayesian inverse(SFBI) modeling approach to constrain seasonal variations in CH_4 *** indicate that in 2018 agricultural soils(AGS,rice production) were the main driver of seasonal variability in atmospheric CH_4 *** was an underestimation of emissions from AGS in the a priori inventories(EDGAR—Emissions Database for Global Atmospheric Research v432 or v50),especially during the growing *** CH_4 emissions from AGS accounted for 39%(4.58 Tg,EDGAR v432) to 47%(5.21 Tg,EDGAR v50) of the total CH_4 *** posteriori natural emissions(including wetlands and water bodies) were1.21 Tg and 1.06 Tg,accounting for 10.1%(EDGAR v432) and 9.5%(EDGAR v50) of total emissions in the YRD *** show that the dominant factor for seasonal variations in atmospheric concentration in the YRD was AGS,followed by natural *** summer,AGS contributed 42%(EDGAR v432) to 64%(EDGAR v50) of the CH_4 concentration enhancement while natural sources only contributed about 10%(EDGAR v50) to 15%(EDGAR v432).In addition,the newer version of the EDGAR product(EDGAR v50) provided more reasonable seasonal distribution of CH_4 emissions from rice cultivation than the old version(EDGAR v432).

关键词： CH_4 emissions WRF-STILT seasonal variations Yangtze River Delta

Evaluation of cone fishways to facilitate passage of small-bodied fish

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Aquaculture and Fisheries 2021年第2期6卷 125-134页

作者： Ivor G.Stuart timothy j.Marsden Arthur Rylah Institute for Environmental Research Department of EnvironmentLandWater and Planning123 Brown StreetHeidelbergVictoria 3084Australia Australasian Fish Passage Services 6 Spinifex StreetFern BayNew South Wales 2295Australia

Fishways are being provided more regularly than ever before and new designs are needed to provide passage for whole fish *** recent progress,fishways have frequently performed poorly,especially for small-bodied fish(i.e.10-100 mm long),which can form large aggregations below stream *** was the genesis for the development of the cone fishway design,a new style of technical fishway which consists of a series of pre-fabricated cone-shaped concrete baffles installed laterally within a concrete *** cone design arose from the need to install rock ramp fishways at remote sites where rock was unavailable and where maintenance would be *** objective of the present study was to evaluate the suitability of the new cone fishway design to provide passage for small-bodied diadromous species(i.e.jor ecological *** fishways provide a useful and novel option to improve passage of small-bodied fish,at appropriate sites,and contribute to a contemporary vision of restoration of whole fish communities.

关键词： fishway fish migration fish communities Australia tidal barrier Fitzroy River Norman River Maribyrnong River