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Forging a Cage into a Chain:Stepw.se Transformation of P_(4) by Silylenes to a Si_(3)P_(4) Motif

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CCS Chemistry 2022年第6期4卷 1843-1849页

作者： Xiaofei Sun Alexander Hinz peter w.Roesky Institute of Inorganic Chemistry Karlsruhe Institute of Technology(KIT)76131 Karlsruhe

w. have discovered a route to access the longest low.valent molecular silaphospha-chain,a sevenmembered chain structure that incorporates three silicon and four phosphorus atoms by stepw.se activation of w.ite phosphorus(P_(4))using tw. different silylene *** chain species w.s formed via a highly reactive polyphosphide *** isolation of a stable analogue of this reaction intermediate w.s achieved by stepw.se reaction w.th mono and bis(silylenes).Due to the rigidity of the ferrocenediyl framew.rk of the bis(silylene),the isomerization process of the chain structure w.s *** studies such as natural bond orbital and atoms in molecules analyses of the seven-membered chain species indicated some degree of delocalization of the double bond system.

关键词： phosphorus P_(4)activation silylene silicon main group synthesis

Nucleation of Supercooled w.ter by Neutrons: Latitude Dependence and Implications for Cloud Modelling

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Atmospheric and Climate Sciences 2024年第2期14卷 221-232页

作者： peter w. w.lson Elizabeth w.lson-Park Abraham G. w.lson Department of Physics The University at Albany SUNY Albany USA Scripps Institution of Oceanography University of California San Diego USA Philanthropy Australia Sydney Australia The King’ s Institute The King&#8217s School Parramatta Australia

It has recently been show. that incident particles, neutrons, can initiate the freezing in a supercooled w.ter volume. This new.finding may have ramifications for the interpretation of both experimental data on the nucleation of laboratory samples of supercooled w.ter and perhaps more importantly on the interpretation of ice nucleation involved in cloud physics. For example, if some fraction of the cloud nucleation previously attributed to dust, soot, or aerosols has been caused by cosmogenic neutrons, fresh consideration is required in the context of climate models. Moreover, as cosmogenic neutrons, most being muon-induced, have much greater flux at high latitudes, estimates of ice nucleates in these regions may be larger than required to accurately model cloud and condensation properties. This discrepancy has been pointed out in IPCC reports. Our paper discusses the connection betw.en the new.concept of neutrons nucleating supercooled w.ter and the need for a new.source of nucleation in high latitude clouds, ideally causing others to review.current data, or to analyse future data w.th this idea in mind. .

关键词： Climate Models Ice Nucleation Neutrons Supercooling

Methyl-β-cyclodextrin enhanced biodegradation of polycyclic aromatic hydrocarbons and associated microbial activity in contaminated soil

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Journal of Environmental Sciences 2012年第5期24卷 926-933页

作者： peter Christie Agri-Environment Branch Agri-Food and Biosciences Institute Newforge Lane Belfast BT9 5PX United Kingdom

The contamination of soils by polycyclic aromatic hydrocarbons （PAHs） is a w.despread environmental problem and the remediation of PAHs from these areas has been a major concern. The effectiveness of many in situ bioremediation systems may be constrained by low.contaminant bioavailability due to limited aqueous solubility or a large magnitude of sorption. The objective of this research w.s to evaluate the effect of methyl-β-cyclodextrin （MCD） on bioaugmentation by Paracoccus sp. strain HPD-2 of an aged PAH-contaminated soil. w.en 10% （w.w. MCD amendment w.s combined w.th bioaugmentation by the PAH-degrading bacterium Paracoccus sp. strain HPD-2, the percentage degradation of total PAHs w.s significantly enhanced up to 34.8%. Higher counts of culturable PAH- degrading bacteria and higher soil dehydrogenase and soil polyphenol oxidase activities w.re observed in 10% （w.w. MCD-assisted bioaugmentation soil. This MCD-assisted bioaugmentation strategy show.d significant increases （p 〈 0.05） in the average w.ll color development （Aw.D） obtained by the BIOLOG Eco plate assay, Shannon-w.aver index （H） and Simpson index （λ） compared w.th the controls, implying that this strategy at least partially restored the microbiological functioning of the PAH-contaminated soil. The results suggest that MCD-aided bioaugmentation by Paracoccus sp. strain HPD-2 may be a promising practical bioremediation strategy for aged PAH-contaminated soils.

关键词： polycyclic aromatic hydrocarbons methyl-β-cyclodextrin biodegradation Paracoccus sp. strain HPD-2 microbial activity

Detrital zircon U-Pb-He double dating: A method of quantifying long- and short-term exhumation rates in collisional orogens

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Science China Earth Sciences 2014年第11期57卷 2702-2711页

作者： Christina Yan w.NG Ian H.CAMPBELL peter w.REINERS Charlotte M.ALLEN Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of Geochemistry Chinese Academy of Sciences Research School of Earth Sciences The Australian National UniversityCanberra ACT 0200 Australia Department of Geosciences University of ArizonaTucson AZ 85721 USA

A U-Pb-He double-dating method is applied to detrital zircons w.th core-rim structure from the Ganges River in order to de- termine average short and long-term exhumation rates for the Himalayas. Long-term rates are calculated from the U/Pb ages of metamorphic rims of the grains that formed during the Himalayan orogeny and their crystallization temperatures, w.ich are calculated from the Ti-in-zircon thermometer. Short-term rates are calculated from （U-Th）/He ages of the grains w.th appro- priate closure temperatures. The results show.that short-term rates for the Himalayas, w.ich range from 0.70 ± 0.09 to 2.67 ± 0.40 km/Myr and average 1.75 ± 0.59 （1δ） km/Myr, are higher and more varied than the long-term rates, w.ich range from 0.84 ±0.16 to 1.85 ± 0.35 km/Myr and average 1.26 ±0.25 （let） km/Myr. The differences betw.en the long-term and short-term rates can be attributed to continuous exhumation of the host rocks in different mechanisms in continental collision orogen. The U/Pb ages of 44.0 ± 3.7 to 18.3 ±0.5 Ma for the zircon rims indicate a protracted episode of -：25 Myr for regional metamorphism of the host rocks at deeper crust, w.ereas the （U-Th）/He ages of 42.2 ± 1.8 to 1.3 ± 0.2 Ma for the zircon grains represent a protracted period of -40 Myr for exposure of the host rocks to shallow.r crustal level. In particular, the oldest （U-Th）/He ages of the zircon grains are close to the oldest U/Pb ages for the rims, indicating that some parcels of the rocks that contain zircons w.re rapidly exhumed from deep to shallow.levels in the stage of collisional orogeny. On the other hand, some parcels of the rocks may have been carried upw.rds by thrust faults in the post-collisional stage. The parcels could be carried upw.rds by the thrust faults that steepen as they near the surface, or by transient movement faults so that areas of rapid exhu- mation became areas of slow.exhumation and visa versa on a time scale of a few.Myr in order to maintain the continuous ex- huma

关键词： zircon U-Pb-He double-dating method Himalayas exhumation rate collisional orogen

Cirrhotic portal hypertension: From pathophysiology to novel therapeutics

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w.rld Journal of Gastroenterology 2020年第40期26卷 6111-6140页

作者： Lakmie S Gunarathne Harinda Rajapaksha Nicholas Shackel peter w.Angus Chandana B Herath Department of Medicine Melbourne Medical SchoolThe University of MelbourneHeidelbergVIC 3084Australia School of Molecular Science College of ScienceHealth and EngineeringLa Trobe UniversityBundooraVIC 3086Australia ANZAC Research Institute ConcordNSW 2139Australia Department of Gastroenterology Austin HealthHeidelbergVIC 3084Australia South w.stern Sydney Clinical School Faculty of MedicineUniversity of New South WalesIngham Institute for Applied Medical Research1 Campbell StreetLiverpoolNSW 2170Australia

Portal hypertension and bleeding from gastroesophageal varices is the major cause of morbidity and mortality in patients w.th cirrhosis. Portal hypertension is initiated by increased intrahepatic vascular resistance and a hyperdynamic circulatory state. The latter is characterized by a high cardiac output, increased total blood volume and splanchnic vasodilatation, resulting in increased mesenteric blood flow. Pharmacological manipulation of cirrhotic portal hypertension targets both the splanchnic and hepatic vascular beds. Drugs such as angiotensin converting enzyme inhibitors and angiotensin Ⅱ type receptor 1 blockers, w.ich target the components of the classical renin angiotensin system(RAS), are expected to reduce intrahepatic vascular tone by reducing extracellular matrix deposition and vasoactivity of contractile cells and thereby improve portal hypertension. How.ver, these drugs have been show. to produce significant offtarget effects such as systemic hypotension and renal failure. Therefore, the current pharmacological mainstay in clinical practice to prevent variceal bleeding and improving patient survival by reducing portal pressure is non-selective-blockers(NSBBs). These NSBBs w.rk by reducing cardiac output and splanchnic vasodilatation but most patients do not achieve an optimal therapeutic response and a significant proportion of patients are unable to tolerate these *** statins, used alone or in combination w.th NSBBs, have been show. to improve portal pressure and overall mortality in cirrhotic patients, further randomized clinical trials are w.rranted involving larger patient populations w.th clear clinical end points. On the other hand, recent findings from studies that have investigated the potential use of the blockers of the components of the alternate RAS provided compelling evidence that could lead to the development of drugs targeting the splanchnic vascular bed to inhibit splanchnic vasodilatation in portal hypertension. This rev

关键词： Portal hypertension Cirrhosis Intrahepatic vascular resistance Hyperdynamic circulatory state Splanchnic vasodilatation Portal blood flow Non-selective betablockers Alternate renin angiotensin system

Sexually transmitted infections of the anus and rectum

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w.rld Journal of Gastroenterology 2014年第41期20卷 15262-15268页

作者： Roland Assi peter w.Hashim Vikram B Reddy Hulda Einarsdottir w.lter E Longo Department of Surgery Yale University School of Medicine

Sexually transmitted infections(STIs) represent a significant public health *** STIs,once thought to be on the verge of extinction,have recently *** change is thought to be partially related to an increase in STIs of the anus and ***,the global human immunodeficiency virus and acquired immunodeficiency syndrome(HIV/AIDS) epidemic has contributed to the emergence of particular anorectal lesions that require specialized *** this report,w. review.common anorectal STIs that are frequently referred to colorectal surgeons in the United ***,clinical presentation,and management are summarized,including the latest treatment *** particularity of anorectal diseases in HIV/AIDS is addressed,along w.th recent trends in anal cytology and human papillomavirus vaccination.

关键词： Sexually transmitted disease Rectal disease Sexual behavior Human papillomavirus Human immunodeficiency virus Perianal disease Highly active antiretroviral therapy Human papilloma virus vaccines Anal cytology

Moderate Hyperthermia Induces Apoptosis in Metaphase-Arrested Cells But Not in Interphase Hela Cells

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Advances in Biological Chemistry 2016年第3期6卷 126-139页

作者： James R. Paulson Agnes Kecskeméti Kresch peter w. Mesner Department of Chemistry University of Wisconsin Oshkosh WI USA Prevea St. Mary’s Health Center Green Bay WI USA Department of Biological Sciences University of Wisconsin Whitewater WI USA

Metaphase-arrest agents and hyperthermia are both know. to be capable of inducing apoptosis, and they have been used, separately, in cancer treatments. Here, w. have examined w.ether the tw. treatments together may have a synergistic effect. w. find that w.en H-HeLa cells are arrested in metaphase w.th spindle poisons (nocodazole or paclitaxel) and then subjected to mild heat treatment (41.5℃), they exhibit morphological changes typical of apoptosis w.thin three hours. Moreover, those changes are blocked by the pan-caspase inhibitor zVAD-fmk, indicating apoptosis, and activated Procaspase 3 is detected by immunoblotting and by staining w.th the fluoresce-in-labelled caspase inhibitor FAM-VAD-fmk. Interphase cells treated in the same w.y do not under-go apoptosis, even w.th spindle poisons present. Induction of apoptosis is more rapid w.en the cells have been arrested longer in metaphase, suggesting that accumulation or depletion of some cellular component(s) during metaphase-arrest may make them more susceptible to hyperthermia. Further w.rk is in progress to test w.ether other cell lines exhibit the same behavior and to learn more about the mechanism. The phenomenon is of interest because it may provide clues to how.hyperthermia induces cell death and may yield novel therapeutic approaches to block or stimulate apoptosis.

关键词： Apoptosis Caspase Heat Treatment H-Hela Hyperthermia Metaphase-Arrest Mitosis Nocodazole Paclitaxel zVAD-fmk

A Lack of Effect on Patient Satisfaction Scores in One Large Urban Emergency Department

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International Journal of Clinical Medicine 2012年第7期3卷 740-743页

作者： peter w. Crane Bryce Yerman Sandra M. Schneider School of Medicine and Dentistry University of Rochester Rochester USA

Background: To deal w.th emergency department crow.ing and long w.its before patient care, many institutions have placed a doctor in the triage area to initiate treatment and testing. Objective: to determine the effect of a doctor in triage on patient satisfaction scores. Methods: This is an observational study comparing the patient satisfaction scores from days w.en a physician w.s in triage to days w.en a physician w.s not present. The study w.s conducted in the ED of an urban academic medical center w.th excellent primary care resources and payer mix (7% self pay, 11% Medicaid). Results: There w.s a mean of 4 (95% CI 3.1 - 4.5) surveys returned for each day w.en there w.s a doctor in triage and a mean of 5 (95% CI 4.3 - 5.7) surveys for each day w.thout a doctor in triage. Overall satisfaction for the days w.th a doctor in triage w.s 79.9 ± 10.5 (95% CI 77.7, 82.1) compared to 78.8 ± 9.2 (95% CI 76.5, 81.1) (p = 0.9) on days w.thout a doctor in triage. Conclusion: In this setting, there w.s no effect of a doctor in triage on patient satisfaction scores. w.ile a doctor in triage may be valuable and cost effective in some settings, it may not provide appropriate benefit in all settings. w. suggest that facilities trial a physician in triage program and measure predetermined outcomes such as patient satisfaction scores, length of stay and the percentage of patients left w.thout being seen before investing in additional staffing and cost to sustain such a program.

关键词： Emergency Department Crow.ing Triage Physician in Triage Patient Satisfaction

Neurotransmitter systems in mouse airw.ys

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中国药理学与毒理学杂志 2017年第10期31卷 1015-1016页

作者： peter w.ABEL Cameron M KIEFFER Ya-ping TU Department of Pharmacology Creighton University School of Medicine

OBJECTIVE The objective of this study w.s to characterize the neurotransmitter systems that cause constriction of murine *** Murine precision cut lung slices(PCLS)and trachea w.re prepared,placed into perfusion chambers equipped w.th platinum electrodes and stimulated transmurally(1.0 ms,50 V,0.1-30 Hz).To measure PCLS constriction,changes in airw.y luminal area in response to electric field stimulation(EFS)w.re captured as video images quantified using Image J *** trachea,changes in isometric tension w.re recorded using Grass force *** response curves w.re generated in the absence and the presence of the inhibitors magnesium,atropine and capsaicin and responses analyzed and compared using a student's t-test(Pw.y constriction in a frequency-dependent manner that w.s best fit by a biphasic ***-specific stimulation w.s verified by Mg^(2+) *** airw.y constriction to 30 Hz EFS in PCLS w.s(51.8±3.0)%w.ile tracheal constriction averaged(551±80)***,in PCLS the muscarinic receptor antagonist atropine(10μmol·L^(-1))blocked(99.5±7.2)%of EFS induced constriction at 1 Hz,but only blocked(23.3±3.8)%of EFS induced constriction at 30 Hz and eliminated the first phase but not the second phase of the biphasic EFS *** w.th capsaicin to deplete sensory neurotransmitters significantly increased EFS constriction supporting the presence of sensory neurotransmitter systems in *** These data are consistent w.th parasympathetic constriction of airw.ys by acetylcholine at low.r EFS frequencies w.ile higher frequencies release sensory dilator *** data provide evidence for multiple nerve types innervating airw.ys w.ich may provide novel targets for treatment of lung disease.

关键词： airw.ys nerve stimulation airw.y constriction atropine capsaicin