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Atrial fibrillation in the elderly: Is ablation ready for prime time ?

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j.urnal of Geriatric Cardiology 2005年第2期2卷 101-102页

作者： allen j. Solomon George Washington University Hospital

Atrial fibrillation is the most common sustained arrhythmia and results in significant morbidity, especially in the elderly. The prevalence of atrial fibrillation increases dramatically with advancing age to almost 6% in individuals older than 65 years. In fact, 84% of people with atrial fibrillation are over 65 years of age.1 Additionally, the risk of stroke increases with advancing age, such that one-third of strokes in patients over the age of 65 are caused by atrial fibrillation.

关键词： Is ablation ready for prime time Atrial fibrillation in the elderly

Ecological monophagy in Tasmanian Graphium macleayanum moggana with evolutionary reflections of ancient angiosperm hosts

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Insect Science 2006年第6期13卷 451-460页

作者： j. MARK SCRIBER GEOFF R. allen PAUL W. WALKER School of Agricultural Science/TIAR University of Tasmania Hobart Australia Department of Entomology Michigan StateUniversity East Lansing Michigan USA

Local host plant specialization in an insect herbivore may be caused by numerous factors, including host-specific natural enemy pressures or a local lack of suitable host-plant choices that are available elsewhere in its range. Such local specialization or ＂ecological monophagy＇, for whatever reason, may reflect reduced ability to behaviourally accept or physiologically utilize other allopatric hosts that are naturally used elsewhere by the species. We tested this feeding specialization hypothesis using the Tasmanian subspecies of Macleay＇s swallowtail butterfly, Graphium macleayanum moggana （Papilionidae）, which uses only a single host-plant species, Antherosperma moschatum （southern sassafras, of the Monlmiaceae）. Further north, this same butterfly species （G. m. macleayanum） uses at least 13 host-plant species from seven genera and four families （Lauraceae, Rutaceae, Winteraceae, and Monlmiaceae）. Our larval feeding assays with G. m. moggana from Tasmania showed that certain Magnoliaceae and Lauraceae could support some larval growth to pupation. However, such growth was slower and survival was lower than observed on their normal southern sassafras host （Monimiaceae）. We also found that toxicity of particular plant species varied tremendously within plant families （for both the Magnoliceae and the Monlmiaceae）.

关键词： Antherosperma detoxification Lauraceae Magnoliaceae Monimiaceae Papilionldae phytochemistry Rutaceae specialist swallowtail butterflies Winteraceae

Relationships between regulated DBPs and emerging DBPs of health concern in U.S. drinking water

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j.urnal of Environmental Sciences 2022年第7期34卷 161-172页

作者： Stuart W.Krasner Ai j.a Chih-Fen T.lee Raha Shirkhani j.shua M.allen Susan D.Richardson Michael j.Plewa Metropolitan Water District of Southern California Water Quality LaboratoryCA 91750USA Department of Chemistry and Biochemistry University of South CarolinaSC 29208USA Department of Crop Sciences University of Illinois at Urbana-ChampaignIL 61801USA Safe Global Water Institute University of Illinois at Urbana-ChampaignIL 61801USA

A survey was conducted at eight U.S. drinking water plants, that spanned a wide range of water qualities and treatment/disinfection practices. Plants that treated heavily-wastewaterimpacted source waters had lower trihalomethane to dihaloacetonitrile ratios due to the presence of more organic nitrogen and HAN precursors. As the bromide to total organic carbon ratio increased, there was more bromine incorporation into DBPs. This has been shown in other studies for THMs and selected emerging DBPs(HANs), whereas this study examined bromine incorporation for a wider group of emerging DBPs(haloacetaldehydes, halonitromethanes). Moreover, bromine incorporation into the emerging DBPs was, in general, similar to that of the THMs. Epidemiology studies that show an association between adverse health effects and brominated THMs may be due to the formation of brominated emerging DBPs of heath concern. Plants with higher free chlorine contact times before ammonia addition to form chloramines had less iodinated DBP formation in chloraminated distribution systems, where there was more oxidation of the iodide to iodate(a sink for the iodide) by the chlorine. This has been shown in many bench-scale studies(primarily for iodinated THMs), but seldom in full-scale studies(where this study also showed the impact on total organic iodine. Collectively, the THMs, haloacetic acids, and emerging DBPs accounted for a significant portion of the TOCl, TOBr, and TOI;however, ~50% of the TOCl and TOBr is still unknown. The correlation of the sum of detected DBPs with the TOCl and TOBr suggests that they can be used as reliable surrogates.

关键词： Disinfection by-products Total organic bromine Total organic iodine Trihalomethanes Haloacetonitriles Haloacetaldehydes Iodo-trihalomethanes Iodoacetic acids

The supernova remnant CTB 37B and its associated magnetar CXOU j.71405.7-381031:evidence for a magnetar-driven remnant

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Research in Astronomy and Astrophysics 2011年第6期11卷 625-630页

作者： j.E.Horvath M.P.allen Instituto de Astronomia Geofísica e Ciências Atmosféricas-Universidade de So PauloRua do Mato122605508-900 Cidade Universitria So Paulo SPBrazil CEFET So Paulo Rua Pedro Vicente 62501109-010Caninde'So Paulo SPBrazil

We discuss the association between the candidate magnetar CXOU j.71405.7-381031 and the supernova remnant CTB *** recent detection of the period derivative of the obj.ct allowed an estimation of a young characteristic age of only ～ *** value is too small to be compatible even with the minimum radius of the remnant being ≥ 10 pc,the value corresponding to the lower limit of the estimated distance of 10.2 ± 3.5 kpc,unless the true distance happens to be even smaller than the lower *** argue that a consistent scenario for the remnant＇s origin,in which the latter is powered by the energy inj.cted by a young magnetar,is indeed more accurate to explain the young age,and demonstrates its non-standard（***-driven） nature.

关键词： stars:supernova — stars:neutron

The CCD instrument background of the SMILE SXI

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Earth and Planetary Physics 2024年第1期8卷 15-24页

作者： M.W.j.Hubbard O.Hetherington D.j.Hall T.W.Buggey S.Parsons T.Arnold A.Holland C.Pagani S.Sembay Centre for Electronic Imaging The Open UniversityMilton KeynesMK76AAUK X-ray and Observational Astronomy Group Department of Physics&AstronomyUniversity of LeicesterLE17RHUK

The ESA and CAS SMILE mission orbit is highly elliptical and will pass through multiple radiation *** Soft X-ray Imager(SXI)instrument aboard has a radiation shutter door designed to close when the surrounding radiation flux is *** shutter door will close when passing below an altitude threshold to protect against trapped particles in the Earth’s Van allen ***,two radiation environments can be approximated based on the shutter door position:open and *** instrument background for the CCDs(Charge-Coupled Devices)that form the focal plane array of the SXI were evaluated for the two *** to the correlation of the space environment with the solar cycle,the solar minima and maxima,the background was also evaluated at these two *** results demonstrated that the highest instrument background will occur during solar minima due to the main contributing source being Galactic Cosmic Rays(GCRs).It was also found that the open background was highest for solar minima and that the closed background was highest during solar *** is due to the radiation shutter door acting as a scattering centre and the changes in the energy flux distribution of the GCRs between the two solar extremes.

关键词： instrument background X-ray astronomy space radiation

Derivation of a Formula for Mountain Height as a Function of Rank in Height

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j.urnal of Applied Mathematics and Physics 2023年第11期11卷 3565-3584页

作者： Edward j. allen Department of Mathematics and Statistics Texas Tech University Lubbock USA

The relationship between mountain height and rank in height for a mountainous region is examined. A stochastic differential equation model is derived for the evolution of mountain elevations. The derivation is based on simple assumptions about tectonic and erosion processes in mountain elevation dynamics. At any given time, the model yields a CIR-type probability density for mountain heights. As data are often available for mountains of greatest elevation in a region, the tail of the CIR density is studied and compared with mountain height data for the highest mountains in the region. The tail density is proportional to the product of a power of height and an exponential function of height, i.e., hb-1exp(-ah) where h is mountain height and a and b are constants. The inverse distribution function of the tail probability density leads to a formula that relates rank in height to the corresponding mountain height. The formula provides, for example, a decreasing sequence of theoretical mountain heights for the region. The derived formula is tested against mountain height data sets for several mountainous regions in the British Isles, Continental Europe, Northern Africa, and North America. The derived formula provides an excellent fit to the mountain height data ranked by height.

关键词： Mountain Height Distribution SDE Geophysics Stochastic Model Orology

Coordination chemistry of surface-associated ligands for solid-liquid adsorption of rare-earth elements

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j.urnal of Rare Earths 2023年第1期41卷 1-18页

作者： j.ssica L.Hovey Timothy M.Dittrich Matthew j.allen Department of Chemistry Wayne State University5101 Cass AvenueDetroitMI48202USA Department of Civil and Environmental Engineering 5050 Anthony Wayne DriveWayne State UniversityDetroitMIl48202USA

General guidelines for the design of ligands for the enrichment of rare-earth elements by solid-liquid adsorption are described using coordination *** properties of ligands include selectivity of metal ions based on adj.stment of donor atom polarizability,denticity,and the pKarange of the binding *** selectivity of solid-phase materials for the enrichment of rare-earth ions by the ligand design guidelines is outlined,with special consideration of additional variable factors including steric hindrance,saturated binding sites,variability in speciation caused by the identity of counterions and ionic strength,and size-exclusivity in ligands stemming from differences in bite angle,preo rganization of ligands,or intraligand *** review analyzes some principles of selectivity of rare-earth elements with ligands organized by donor type from examples collected from reports published between 2009 and 2021.

关键词： Chelating ligand Coordination chemistry Solid-phase material Rare-earth element Separation Solid-liquid extraction

On environmental threats to male infertility

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Asian j.urnal of Andrology 2013年第2期15卷 199-200,I0005页

作者： allen j.Wilcox j.ns Peter E Bonde Epidemiology Branch National Institute of Environmental Health Sciences Durham NC 27709-2233 USA Department of Occupational and Environmental Medicine University Hospital of Copenhagen Copenhagen NV DK-2400 Denmark

The possibility that environmental pollutants damage human fertility is a topic of both public concern and scientific interest. The effect of environmental factors on male fertility （semen parameters） has been a special focus, stimulated in part by the dramatic damage inflicted by the pcstlcide DBCP on testicular function. Extensive searches for testicular toxicants （in particular, the proposed effects of endocrine-disrupting compounds through fetal exposure） have produced little hard evidence of impairment in humans. This scarcity of evidence may reflect the difficultles of studying human fertility. Future fertifity studies should consider the wide spectrum of environmental exposures that plausibly affect reproduction.

关键词： TESTICULAR DYSGENESIS SYNDROME IN-UTERO EXPOSURE SPERM COUNTS SEMEN QUALITY ENDOCRINE DISRUPTION REPRODUCTIVE-TRACT FERTILITY PREGNANCY PHTHALATE SMOKING

A plant-based diet and hypertension

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j.urnal of Geriatric Cardiology 2017年第5期14卷 327-330页

作者： Sarah Alexander Robert j.Ostfeld Kathleen allen Kim A Williams Rush University Medical Center Division of Cardiology Chicago IL USA Montefiore Medical Center Division of Cardiology Bronx NY USA New York University Department of Nutrition & Food Studies NY USA

Hypertension is an insidious, common, and deadly dis-ease, often detected incidentally at a routine doctor＇s visit orworkplace health screening. Worldwide, it is estimated thatone billion people have hypertension and... 详细信息

关键词： Hypertension Vegan Vegetarian Plant-based diet