Publications by authors named "Jack Chapman"

Small lakes are common across the Boreal-Arctic zone. Due to shallowness and high shoreline-surface area ratios, they are abundant in aquatic macrophytes. Vegetated littoral zones have been suggested to count as wetlands when quantifying carbon sinks and sources, but the actual magnitude of aquatic vegetation is seldom quantified.

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Despite the wide body of research into prevention and treatment of nonunion, current bone fracture therapies remain suboptimal in their efficacy. Previous animal studies show that MES-1022, a bone-targeted prodrug that activates the prostaglandin E2 receptor EP4, stimulates bone healing when applied locally in uneventful defects. Here we investigated the healing capacity of systemically administered MES-1022 in a rat femoral critical size segmental defect.

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Carbon-water interaction studies between aquatic and terrestrial ecosystems are especially needed today in Arctic and Boreal regions, as they are facing drastic warming and precipitation shifts. Despite the importance of streams in the carbon cycle, northern stream-based studies are scarce, owing to a lack of measurements throughout the north, and possibly skewing global greenhouse gas estimates. We used a combination of multiscale measurements to quantify water sources (HO isotope proxies), carbon availability (dissolved in/organic carbon concentrations) and quality (water absorbance, SUVA -index), microbial community structure (16S rRNA sequencing), and carbon dioxide (CO) and methane (CH) fluxes and concentrations.

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Gas flow is fundamental for driving tidal ventilation and, thus, the speed of lung motion, but current bias flow settings to support the preterm lung after birth do not have an evidence base. We aimed to determine the role of gas bias flow rates to generate positive pressure ventilation in initiating early lung injury pathways in the preterm lamb. Using slower speeds to inflate the lung during tidal ventilation (gas flow rates 4-6 L/min) did not affect lung mechanics, mechanical power, or gas exchange compared with those currently used in clinical practice (8-10 L/min).

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Climate warming and projected increase in summer droughts puts northern peatlands under pressure by subjecting them to a combination of gradual drying and extreme weather events. The combined effect of those on peatland functions is poorly known. Here, we studied the impact of long-term water level drawdown (WLD) and contrasting weather conditions on leaf phenology and biomass production of ground level vegetation in boreal peatlands.

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Background: Effective lung protective ventilation requires reliable, real-time estimation of lung volume at the bedside. Neonatal clinicians lack a readily available imaging tool for this purpose.

Objective: To determine the ability of lung ultrasound (LUS) of the dependent region to detect real-time changes in lung volume, identify opening and closing pressures of the lung, and detect pulmonary hysteresis.

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Foldable acrylic posterior chamber intraocular lenses (PC IOLs) can be removed via a variety of methods. In this technique, the PC IOL is freed from its position in the capsular bag or sulcus space and raised into the anterior chamber. The IOL is manipulated such that a haptic is externalized through a 2.

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Chiral amines bearing a stereocenter in the α position are ubiquitous compounds with many applications in the pharmaceutical and agrochemical sectors, as well as in catalysis. Catalytic asymmetric Mannich additions represent a valuable method to access such compounds in enantioenriched form. This work reports the first enantio- and diastereoselective addition of commercially available p-toluenesulfonylmethyl isocyanide (TosMIC) to ketimines, affording 2-imidazolines bearing two contiguous stereocenters, one of which is fully-substituted, with high yields and excellent stereocontrol.

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Objective: The Epiducer lead delivery system is a novel lead delivery device that can be used to percutaneously implant S-Series paddle leads (St. Jude Medical, Plano, TX, USA) as well as multiple percutaneous leads obviating the need for laminectomy and/or multiple needle sticks, respectively. This study evaluates the safety and usage of the Epiducer lead delivery system.

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Rising atmospheric carbon dioxide (CO2) concentration ([CO2]) could alter terrestrial carbon (C) cycling by affecting plant growth, litter chemistry and decomposition. How the concurrent increase in tropospheric ozone (O3) concentration ([O3]) will interact with rising atmospheric [CO2] to affect C cycling is unknown. A major component of carbon cycling in forests is fine root production, mortality and decomposition.

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