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Natural regeneration responses to thinning and burning treatments in ponderosa pine forests and implications for restoration

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Journal of Forestry Research 2022年第3期33卷 741-753页

作者： Tzeidle N.Wasserman Amy E.M.Waltz John paul Roccaforte Judith d.Springer Joseph E.Crouse Ecological Restoration Institute Northern Arizona UniversityP.O.Box 15017FlagstaffAZ86011-5017USA

Understanding naturally occurring pine regeneration dynamics in response to thinning and burning treatments is necessary not only to measure the longevity of the restoration or fuels treatment,but also to assess how well regeneration meets forest sustainability guidelines and whether natural regeneration is sufficient for maintaining a sustainable forest structure and composition.A synthesis review was carried out on the effects of mechanical thinning and prescribed burn treatments on natural pine regeneration response in frequent-fire ponderosa pine forests across the western United *** focus was on site-specific variability in pine regeneration dynamics,temporal trends in regeneration presence and abundance,and response to treatment as described in the current literature using 29 studies that met our evidence-based review *** showed that the effects of thinning and burning treatments on regeneration depended on time since *** thinning,prescribed burning,and thinning plus burn treatments all increased seedling density,but there was high variability among sites and *** were mixed results in the short-term(d decreasing regeneration,and a general increase in regeneration 11−20 years *** long-term studies(>20 years)concluded that stands can return to pre-treatment densities in terms of total trees per hectare and forest floor duff levels when there are no maintenance treatments *** studies showed the average ponderosa pine seedling presence,survival and growth found in today’s forests to be at a high density;this combined with missed fire cycles could contribute to future fire risk and reduce the efficacy of maintaining fuel reduction goals.

关键词： Regeneration Ponderosa pine Frequent-fire Treatments Thinning Burning

Changes in fetal mannose and other carbohydrates induced by a maternal insulin infusion in pregnant sheep

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Journal of Animal Science and Biotechnology 2015年第2期6卷 222-229页

作者： Laura d Brown Stephanie R Thorn Alex Cheung Jinny R Lavezzi Frederick C Battaglia paul J Rozance Perinatal Research Center Division of Neonatology Department of Pediatrics University of Colorado Denver School of Medicine Center for Women’s Health Research University of Colorado Denver School of Medicine

Background： The importance of non-glucose carbohydrates, especially mannose and inositol, for normal development is increasingly recognized. Whether pregnancies complicated by abnormal glucose transfer to the fetus also affect the regulation of non-glucose carbohydrates is unknown. In pregnant sheep, maternal insulin infusions were used to reduce glucose supply to the fetus for both short （2-wk） and long （8-wk） durations to test the hypothesis that a maternal insulin infusion would suppress fetal mannose and inositol concentrations. We also used direct fetal insulin infusions （1-wk hyperinsulinemic-isoglycemic clamp） to determine the relative importance of fetal glucose and insulin for regulating non-glucose carbohydrates. Results： A maternal insulin infusion resulted in lower maternal （50%, P 〈 0.01） and fetal （35-45%, P 〈 0.01） mannose concentrations, which were highly correlated （r^2 = 0.69, P 〈 0.01）. A fetal insulin infusion resulted in a 50% reduction of fetal mannose （P 〈 0.05）. Neither maternal nor fetal plasma inositol changed with exogenous insulin infusions. Additionally, maternal insulin infusion resulted in lower fetal sorbitol and fructose （P 〈 0.01）. Conclusions： Chronically decreased glucose supply to the fetus as well as fetal hyperinsulinemia both reduce fetal non-glucose carbohydrates. Given the role of these carbohydrates in protein glycosylation and lipid production, more research on their metabolism in pregnancies complicated by abnormal glucose metabolism is clearly warranted.

关键词： Fructose Glucose Inositol Insulin Mannose Pregnancy

Advanced strategies for marine antifouling based on nanomaterial-enhanced functional PdMS coatings

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Nano Materials Science 2024年第4期6卷 375-395页

作者： Xiaohui Shi Hao Wei Wenjun Zhou paul E.d.Soto Rodriguez Cunguo Lin Lei Wang Zhijia Zhang Engineering Harbin Engineering UniversityHarbinChina Qingdao Innovation and development Center of Harbin Engineering University QingdaoChina State key Laboratory for Marin Corrosion and Protection Luoyang Ship Material Research Institute(LSMRI)QingdaoChina School of Chemistry and Chemical Engineering Harbin Institute of TechnologyHarbinChina Instituto de Estudios Avanzados IUdEA Departamento de FísicaUniversidad de La Laguna C/Astrofísico Francisco SanchezS/n.E-38203TenerifeSpain

Marine biofouling seriously affects human marine exploitation and transportation activities,to which marine antifouling(AF)coatings are considered to be the most cost-effective *** the mid-20th century,human beings have dedicated their efforts on developing AF coatings with long cycle and high performance,leading to a large number of non-target organisms?distortion,death and marine environmental ***(PdMS),is considered as one of the representative environment-friendly AF materials thanks to its non-toxic,hydrophobic,low surface energy and AF ***,PdMS AF coatings are prone to mechanical damage,weak adhesion strength to substrate,and poor static AF effect,which seriously restrict their use in the *** rapid development of various nanomaterials provides an opportunity to enhance and improve the mechanical properties and antifouling properties of PdMS coating by embedding *** on our research background and the problems faced in our laboratory,this article presents an overview of the current progress in the fields of PdMS composite coatings enhanced by different nanomaterials,with the discussion focused on the advantages and main bottlenecks currently encountered in this ***,we propose an outlook,hoping to provide fundamental guidance for the development of marine AF field.

关键词： Nanomaterials Antifouling PdMS composites Environment-friendly Marine biofouling

Inpatient management of iron deficiency anemia in pediatric patients with inflammatory bowel disease: A single center experience

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World Journal of Clinical Pediatrics 2024年第1期13卷 107-117页

作者： krishanth Manokaran Jonathan Spaan Giulio Cataldo Christopher Lyons paul d Mitchell Tatyana Sare LoriA Zimmerman paul A Rufo Center for Inflammatory Bowel disease Boston Children's HospitalBostonMA 02115United States Institutional Centers for Clinical and Translational Research Boston Children's HospitalBostonMA 02115United States

BACkGROUNd Screening for iron deficiency anemia(IdA)is important in managing pediatric patients with inflammatory bowel disease(IBd).Concerns related to adverse reactions may contribute to a reluctance to prescribe intravenous(IV)iron to treat IdA in this *** To track the efficacy and safety of IV iron therapy in treating IdA in pediatric IBd patients admitted to our *** A longitudinal observational cohort study was performed on 236 consecutive pediatric patients admitted to our tertiary IBd care center between September 2017 and december 2019.92 patients met study criteria for IdA,of which 57 received IV iron,17 received oral iron,and 18 were discharged prior to receiving iron *** Patients treated with IV iron during their hospitalization experienced a significant increase of 1.9(±0.2)g/dL in mean(±SE)hemoglobin(Hb)concentration by the first ambulatory follow-up,compared to patients who received oral iron 0.8(±0.3)g/dL or no iron 0.8(±0.3)g/dL(P=0.03).One out of 57(1.8%)patients that received IV iron therapy experienced an adverse *** Our findings demonstrate that treatment with IV iron therapy is safe and efficacious in improving Hb and iron levels in pediatric patients with IdA and active IBd.

关键词： Iron deficiency anemia Pediatric inflammatory bowel disease Intravenous iron therapy Inflammatory bowel disease

State of the Art in Alcohol Sensing with 2d Materials

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Nano-Micro Letters 2020年第3期12卷 22-54页

作者： Ramin Boroujerdi Amr Abdelkader Richard paul Faculty of Science and Technology Bournemouth UniversityTalbot CampusFern BarrowPoole BH125BBUK department of Engineering University of CambridgeCambridge CB30FSUK

Since the discovery of graphene,the star among new materials,there has been a surge of attention focused on the monatomic and monomolecular sheets which can be obtained by exfoliation of layered *** materials are known as two-dimensional(2d)materials and offer enormous versatility and *** ultimate single atom,or molecule,thickness of the 2d materials sheets provides the highest surface to weight ratio of all the nanomaterials,which opens the door to the design of more sensitive and reliable chemical *** variety of properties and the possibility of tuning the chemical and surface properties of the 2d materials increase their potential as selective sensors,targeting chemical species that were previously difficult to *** planar structure and the mechanical flexibility of the sheets allow new sensor designs and put 2d materials at the forefront of all the candidates for wearable *** developing sensors for alcohol,the response time is an essential factor for many industrial and forensic applications,particularly when it comes to hand-held ***,we review recent developments in the applications of 2d materials in sensing alcohols along with a study on parameters that affect the sensing *** review also discusses the strategies used to develop the sensor along with their mechanisms of sensing and provides a critique of the current limitations of 2d materials-based alcohol sensors and an outlook for the future research required to overcome the challenges.

关键词： Sensors and biosensors Alcohol probes Electrochemical detectors Ethanol metabolites 2d materials

CR Geometry in 3-d(dedicated to Professor Haim Brezis with admiration)

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Chinese Annals of Mathematics,Series B 2017年第2期38卷 695-710页

作者： paul C.YANG department of mathematics princeton universityFine HallW ashington RoadPrinceton NJ 08544 USA.

CR geometry studies the boundary of pseudo-convex manifolds. By concentrating on a choice of a contact form, the local geometry bears strong resemblence to conformal geometry. This paper deals with the role conformally invariant operators such as the Paneitz operator plays in the CR geometry in dimension three. While the sign of this operator is important in the embedding problem, the kernel of this operator is also closely connected with the stability of CR structures. The positivity of the CR-mass under the natural sign conditions of the Paneitz operator and the CR Yamabe operator is discussed. The CR positive mass theorem has a consequence for the existence of minimizer of the CR Yamabe problem. The pseudo-Einstein condition studied by Lee has a natural analogue in this dimension, and it is closely connected with the pluriharmonic *** author discusses the introduction of new conformally covariant operator P-prime and its associated Q-prime curvature and gives another natural way to find a canonical contact form among the class of pseudo-Einstein contact forms. Finally, an isoperimetric constant determined by the Q-prime curvature integral is discussed.

关键词： Paneitz operator, Embedding problem, Yamabe equation, Mass,P-prime, Q-prime curvature

discrete Element Modeling of a Subduction Zone with a Seafloor Irregularity and its Impact on the Seismic Cycle

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Acta Geologica Sinica(English Edition) 2022年第3期96卷 776-790页

作者： JIAO Liqing CHAN Chung-Han Luc SCHOLTÈS Aurélia HUBERT-FERRARI Frédéric-Victor dONZÉ paul TAPPONNIER SinoProbe Center Chinese Academy of Geological SciencesBeijing 100037China Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China Earthquake-disaster&Risk Evaluation and Management(E-dREaM)Center National Central UniversityTaoyuanChina department of Earth Sciences National Central UniversityTaoyuanChina CNRS IRDOPGCLaboratoire Magma et VolcansUniversitéClermont AuvergneClermont-FerrandFrance department de Geography Universitéde LiegeLiegeBelgium Institut des Sciences de la Terre UniversitéGrenoble AlpesGrenobleFrance National Institute of Natural Hazards MEMCBeijing 100085China

Seafloor irregularities influence rupture behavior along the subducting slab and in the overriding plate,thus affecting earthquake *** seafloor irregularities increase the likelihood of large earthquakes in a subduction zone remains contested,partially due to focus put either on fault development or on rupture ***,we simulate a subducting slab with a seafloor irregularity and the resulting deformation pattern of the overriding plate using the discrete element *** simulations illustrate the rupture along three major fault systems:megathrust,splay and backthrust *** results show different rupture dimensions of earthquake events varying from tens to ca.140 *** results suggest that the recurrence interval of megathrust events with rupture length of ca.100 km is ca.140 years,which is overall comparable to the paleoseismic records at the Mentawai area of the Sumatran *** further propose the coseismic slip amounts decrease and interseismic slip amounts increase from the surface downwards *** conclude that the presence of seafloor irregularities significantly affects rupture events along the slab as well as fault patterns in the overriding plate.

关键词： discrete element modeling subduction zone megathrust splay backthrust faults seamount Mentawai

RETINAL SPECTRAL IMAGING ANd BLOOd FLOW MEASUREMENT

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Journal of Innovative Optical Health Sciences 2010年第4期3卷 255-265页

作者： paul LEMAILLET dONALd d.dUNCAN ART LOMPAdO MOHAMEd IBRAHIM QUAN dONG NGUYEN JESSICA C.RAMELLA-ROMAN department of Biomedical Engineering The Catholic University of America 620 Michigan Ave. N.E.WashingtonDC 20064USA ECE department Portland State University 1900 SW Fourth AvenuePortlandOR 97201USA Polaris Sensor Technologies 200 Westside Square Suite 320 HuntsvilleAL 35801USA Wilmer Eye Institute Johns Hopkins University BaltimoreMD 21287USA

Measurement of both oxygen saturation and blood flow in the retinal vessels has proved to give important information about the eye health and the onset of eye pathologies such as diabetic *** this study,we present the implementation,on a commercially available fundus camera,of a retinal imager and a retina blood flow *** retinal imager uses division of aperture to acquire nine wavelength-dependent sub-images of the *** consideration is taken to improve image transfer by measuring the optical properties of the fundus camera and modeling the optical train in *** part of the setup is calibrated with optical phantoms of known optical properties that are also used to build a lookup table(LUT)linking phantom optical properties to measured *** retina blood flow velocimeter relies on tracking clusters of erythrocytes and uses a fast acquisition camera attached to a zoom lens,with a green illumination *** is provided using a calibrated quartz capillary tube and human blood at a known flow *** properties of liquid phantoms are retrieved from measured reflectance using the LUT,and blood flow measurements in the retina are presented.

关键词： Retinal oximetry fundus ophthalmoscope multi-aperture camera blood flow velocity diabetic retinopathy

Strain-dependent alpha-synuclein spreading in Parkinson's disease and multiple system atrophy

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Neural Regeneration Research 2024年第12期19卷 2581-2582页

作者： Shuyu Zhang paul Lingor department of Neurology School of MedicineUniversity Hospital rechts der IsarTechnical University of MunichMunichGermany department of Neurology University Medical Center GöttingenGöttingenGermany Center for Biostructural Imaging of Neurodegeneration University Medical Center GöttingenGöttingenGermany

Parkinson's disease(Pd) and atypical Parkinsonian syndromes,such as multiple system atrophy(MSA) and dementia with Lewy bodies,are neurodegenerative movement disorders characterized by the accumulation of alphasynuclein(a-syn) *** a-syn aggregates propagate throughout the brain in a prion-like manner,where pathological a-syn recruits endogenous a-syn to form insoluble *** forms representing intermediates on the way to insoluble aggregates result in the most pronounced neurotoxic effects.

关键词： atrophy endogenous atypical