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We present surface mass balance simulations of the Southern Patagonia Icefield (SPI) driven by downscaled reanalysis data. The simulations were evaluated and interpreted using geodetic mass balances, measured point balances and a complete velocity field of the icefield for spring 2004. The high measured accumulation of snow of up to 15.4m w.e. yr–1 (meters water equivalent per year) as well as the high measured ablation of up to 11m w.e. yr–1 is reproduced by the model. The overall modeled surface mass balance was positive and increasing during 1975–2011. Subtracting the surface mass balance from geodetic balances, calving fluxes were inferred. Mass losses of the SPI due to calving were strongly increasing from 1975–2000 to 2000–2011 and higher than losses due to surface melt. Calving fluxes were inferred for the individual glacier catchments and compared to fluxes estimated from velocity data. Measurements of ice thickness and flow velocities at the glaciers' front and spatially distributed accumulation measurements can help to reduce the uncertainties of the different terms in the mass balance of the Southern Patagonia Icefield. [ABSTRACT FROM AUTHOR]

Forest plantations in Chile occupy more than 2.2 million ha and are responsible for 2.1% of the GDP of the country's economy. The ability to accurately predictions of plantations productivity under current and future climate has an impact can enhance on forest management and industrial wood production. The use of process-based models to predict forest growth has been instrumental in improving the understanding and quantifying the effects of climate variability, climate change, and the impact of atmospheric CO 2 concentration and management practices on forest growth. This study uses the 3-PG model to predict future forest productivity Eucalyptus globulus and Pinus radiata. The study integrates climate data from global circulation models used in CMIP5 for scenarios RCP26 and RCP85, digital soil maps for physical and chemical variables. Temporal and spatial tree growth inventories were used to compare with the 3-PG predictions. The results indicated that forest productivity is predicted to potentially increase stand volume (SV) over the next 50 years by 26% and 24% for the RCP26 scenario and between 73% and 62% for the RCP85 scenario for E. globulus and P. radiata, respectively. The predicted increases can be explained by a combination of higher level of atmospheric CO 2 , air temperatures closer to optimum than current, and increases in tree water use efficiency. If the effect of CO 2 is not considered, the predicted differences of SV for 2070 are 16% and 14% for the RCP26 scenario and 22% and 14% for RCP85 for the two species. While shifts in climate and increasing CO 2 are likely to benefit promote higher productivity, other factors such as lack insufficient availability of soil nutrients, events such as increasing frequency and duration of droughts, longer periods of extreme temperatures, competing vegetation, and occurrence of new pests and diseases may compromise these potential gains., (© 2022 John Wiley & Sons Ltd.)

Background: With recent Medicare payment changes, older adults are increasingly likely to be discharged home instead of to extended care facilities after total joint arthroplasty (TJA), and may therefore be at increased risk for readmissions. Identifying risk factors for readmission could help re-align care pathways for vulnerable patients; recent research has suggested preoperative dependency in activities of daily living (ADL) may increase perioperative and postoperative surgical complications. However, the proportion of older surgical patients with ADL dependence before TJA, and the impact of ADL dependency on the frequency and timing of hospital readmissions is unknown., Questions/purposes: (1) What proportion of older adults discharged home after TJA have preoperative ADL dependency? (2) Is preoperative ADL dependency associated with increased risk of hospital readmissions at 30 days or 90 days for older adults discharged home after TJA?, Methods: This was a retrospective cohort analysis of 6270 Medicare fee-for-service claims from 2012 from a 5% national Medicare sample for older adults (older than 65 years) receiving home health care after being discharged to the community after elective TJA. Medicare home health claims were used for two reasons: (1) the primary population of interest was older adults and (2) the accompanying patient-level assessment data included an assessment of prior dependency on four ADL tasks. Activities of daily living dependency was dichotomized as severe (requiring human assistance with all four assessed tasks) or partial/none (needing assistance with three or fewer ADLs); this cutoff has been used in prior research to evaluate readmission risk. Multivariable logistic regression models, clustered at the hospital level and adjusted for known readmission risk factors (such as comorbidity status or age), were used to model the odds of 30- and 90- day and readmission for patients with severe ADL dependence., Results: Overall, 411 patients were hospitalized during the study period. Of all readmissions, 64% (262 of 411) occurred within the first 30 days, with a median (interquartile range [IQR]) time to readmission of 17 days (5 to 46). Severe ADL dependency before surgery was common for older home health recipients recovering from TJA, affecting 17% (1066 of 6270) of our sample population. After adjusting for clinical covariates, severe ADL dependency was not associated with readmissions at 90 days (adjusted odds ratio = 1.20 [95% CI 0.93 to 1.55]; p = 0.15). However, severe preoperative ADL dependency was associated with higher odds of readmission at 30 days (adjusted OR = 1.45 [95% CI 1.11 to 1.99]; p = 0.008)., Conclusions: Severe preoperative ADL dependency is modestly associated with early but not late hospital readmission after TJA. This work demonstrates that it may important to apply a simple screening of ADL dependency preoperatively so that surgeons can guide changes in care planning for older adults undergoing TJA, which may include participation in preoperative rehabilitation (pre-habilitation) or more aggressive follow-up in the 30 days after surgery. Further research is needed to determine whether severe ADL dependence can be modified before surgery, and whether these changes in dependency can reduce readmission risk after TJA., Level of Evidence: Level III, therapeutic study.

Chile hosts some of the sunniest places on earth, which has led to a growing solar energy industry in recent years. However, the lack of high resolution measurements of solar irradiance becomes a critical obstacle for both financing and design of solar installations. Besides the Atacama Desert, Chile displays a large array of "solar climates" due to large latitude and altitude variations, and so provides a useful testbed for the development of solar irradiance maps. Here a new public database for surface solar irradiance over Chile is presented. This database includes hourly irradiance from 2004 to 2016 at 90 m horizontal resolution over continental Chile. Our results are based on global reanalysis data to force a radiative transfer model for clear sky solar irradiance and an empirical model based on geostationary satellite data for cloudy conditions. The results have been validated using 140 surface solar irradiance stations throughout the country. Model mean percentage error in hourly time series of global horizontal irradiance is only 0.73%, considering both clear and cloudy days. The simplicity and accuracy of the model over a wide range of solar conditions provides confidence that the model can be easily generalized to other regions of the world.

Amylin is a 37-amino acid peptide that shares considerable homology with calcitonin gene-related peptide (CGRP). Both peptides exert glycoregulatory actions and produce vasodilation of the cardiovascular system. We wished to determine if amylin exerts vasodilatory action in the perfused mesenteric arterial bed in a manner similar to that of CGRP and if so, to determine if amylin and CGRP share a common mechanism of action. Amylin 10(-8), 10(-7), and 10(-6)M produced significant decreases in perfusion pressure by 18, 34, and 45 mm Hg, respectively, of the perfused mesenteric arterial bed pretreated with guanethidine (7 x 10(-6)M) and precontracted with methoxamine (10(-6)-10(-5)M). Amylin was approximately 10 times less potent than CGRP. This vasodilatory effect was not antagonized by atropine in a concentration (10(-6)M) that blocked the vasodilatory action of acetylcholine (ACh) or of nadolol in a concentration that blocked the response to isoproterenol (ISO 10(-6)M). In contrast, the CGRP receptor antagonist [8-37]hCGRP blocked the response of both amylin and CGRP while failing to block the effect of ISO. The depressor effects of CGRP (10(-8)M), amylin (10(-6)M), and ISO (10(-5)M) were 38, 43, and 42 mm Hg without and 5, 12, and 44 mm Hg with [8-37]hCGRP (10(-7)M), respectively. Simultaneous administration of CGRP and amylin failed to produce an additive effect. The depressor effects of CGRP (10(-8)M), amylin (10(-7)M), and CGRP (10(-8)M) plus amylin (10(-7)M) were 50, 32, and 45 mm Hg, respectively. We conclude that amylin exerts a vasodilator action in the perfused mesenteric arterial bed by acting on CGRP1 receptors and suggest that this glycoregulatory hormone may also exert regulatory actions in the vasculature in a manner similar to that of CGRP.

Neuropeptide Y (NPY) and ATP are considered cotransmitters with norepinephrine (NE) in sympathetic neurons innervating some blood vessels, including those of the mesentery. A prominent action of NPY is to potentiate the postjunctional contractile effect of NE as well as that of other vasoactive agents. We wished to investigate whether NPY also potentiates the contractile effect of ATP and, if so, to determine which receptor subtype mediates such an effect. The effect of NPY, the NPY-Y1-selective agent Leu31Pro34 NPY, and the NPY-Y2-selective fragment NPY 14-36 on the increase in perfusion pressure produced by ATP was examined in rat perfused mesenteric arterial bed. Results demonstrated that both NPY and Leu31Pro34 NPY but not NPY 14-36 potentiated the increase in perfusion pressure produced by ATP. These results suggest that NPY acts on Y1 receptors to enhance the postjunctional response of ATP. The putative NPY antagonist PYX2, but not the putative antagonists benextramine or PYX1, attenuated the effect of NPY, indicating that PYX2 acts as an NPY antagonist in this system. A major action of NPY is to enhance the postjunctional response of both cotransmitters, ATP and NE at the vascular sympathetic neuroeffector junction in the mesenteric arterial bed, and this may be mediated by NPY-Y1 receptors.

We describe our experience in late reconstructions of 35 burned eyelids. On this basis we advocate wide, aggressive release of all scar contractures, including the distal part of the levator when necessary. To cover the resultant defects we use generous full-thickness skin grafts, if available, for both the upper and lower lids. Rarely has a tarsorrhaphy been required, and properly constructed dressings provide satisfactory lid immobilization and permit conjunctival hygiene. During the postoperative period the vision need not be obstructed by a tarsorrhaphy, Frost sutures, or the dressings.