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Regions in high latitudes are experiencing greater climate change than other regions. In this study, the impact of temperature and precipitation on the yield of fifteen cultivars (eight barley [Hordeum vulgare], four oat [Avena sativa], and three wheat [Triticum aestivum]) from a small grain field experiment in Fairbanks and Delta Junction, Alaska, from 1978 to 2018 were analyzed to evaluate their sensitivity to variation in climate that occurred during this period. Using first-difference time series of log yield change and the changes of determinant weather (maximum and minimum temperatures and precipitation) as variables, linear regression and Bayesian simulation models were fitted for analysis. Results showed that of fifteen cultivars, two barley and one wheat had a consistent yield reduction (p

Barley heading date has advanced in Fairbanks (64.83° N, 147.77° W), Alaska, USA. However, it is unclear if this advance coincidently causes weather pattern changes around heading and leads to yield loss. Using the Variety Trial and weather data in Fairbanks and Delta Junction (64.05° N, 145.60° W) from 1991 to 2018, two barley cultivars were selected to analyze the yield and weather trends, the yield variation explained by weather, and the effect of extreme weather on yield. The results showed that the heading date of ‘Otal’ significantly advanced and yield significantly declined in Fairbanks while there were no heading and yield changes of ‘Otal’ in Delta Junction and of ‘Thual’ in both Fairbanks and Delta Junction. The weather pattern changed around heading due to advanced heading of ‘Otal’ in Fairbanks. The climate factors at 7–10 days around heading explained over 50% of ‘Otal’ yield variation in Fairbanks. The results suggest that ‘Otal’ can still be good to plant in Delta Junction but not in Fairbanks. To cope with the climate change in Alaska, the farmers should increase the diversity of barley cultivars, select non-photoperiod sensitive cultivars and cultivars with longer duration from planting to heading, and sow late to avoid the impact on heading and yield.

BackgroundST‐segment elevation myocardial infarction is increasingly common in octogenarians, and optimal management in this cohort is uncertain. This study aimed to describe the outcomes of octogenarians with ST‐segment elevation myocardial infarction treated by primary percutaneous coronary intervention. Methods and ResultsWe analyzed 10 249 consecutive patients with ST‐segment elevation myocardial infarction treated with primary percutaneous coronary intervention between 2005 and 2011 at 8 tertiary cardiac centers across London, United Kingdom. The primary end point was all‐cause mortality at a median follow‐up of 3 years. In total, 1051 patients (10.3%) were octogenarians, with an average age of 84.2 years, and the proportion increased over the study period (P=0.04). In‐hospital mortality (7.7% vs 2.4%, P

BackgroundResearch trials have shown improved short-term outcome with drug-eluting stents (DES) over bare metal stents (BMS) in saphenous vein graft (SVG) percutaneous coronary intervention (PCI), primarily by reducing target vessel revascularization (TVR) for in-stent restenosis. We compared the outcomes in patients undergoing SVG stent implantation treated with DES or BMS. In exploratory analyses we investigated the influence of stent generation and diameter.MethodsData were obtained from a prospective database of 657 patients who underwent PCI for SVG lesions between 2003 and 2011. A total of 344 patients had PCI with BMS and 313 with DES. Propensity scores were developed based on 15 observed baseline covariates in a logistic regression model with stent type as the dependent variable. The nearest-neighbour-matching algorithm with Greedy 5-1 Digit Matching was used to produce two patient cohorts of 313 patients each. We assessed major adverse cardiac events (MACE) out to a median of 3.3 years (interquartile range: 2.1-4.1). MACE was defined as all-cause mortality, myocardial infarction (MI), TVR and stroke.ResultsThere was a significant difference in MACE between the two groups in favour of DES (17.9% DES vs. 31.2% BMS group; p = 0.0017) over the 5-year follow-up period. MACE was driven by increased TVR in the BMS group. There was no difference in death, MI or stroke. Adjusted Cox analysis confirmed a decreased risk of MACE for DES compared with BMS 0.75 (95% confidence interval (CI) 0.52-0.94), with no difference in the hazard of all-cause mortality (hazard ratio: 1.08; 95% CI: 0.77-1.68). However, when looking at stent diameters greater than 4 mm, no difference was seen in MACE rates between BMS and DES.ConclusionsOverall in our cohort of patients who had PCI for SVG disease, DES use resulted in lower MACE rates compared with BMS over a 5-year follow-up period; however, for stent diameters over 4 mm no difference in MACE rates was seen.

The flora of California, a global biodiversity hotspot, includes 2387 endemic plant taxa. With anticipated climate change, we project that up to 66% will experience >80% reductions in range size within a century. These results are comparable with other studies of fewer species or just samples of a region's endemics. Projected reductions depend on the magnitude of future emissions and on the ability of species to disperse from their current locations. California's varied terrain could cause species to move in very different directions, breaking up present-day floras. However, our projections also identify regions where species undergoing severe range reductions may persist. Protecting these potential future refugia and facilitating species dispersal will be essential to maintain biodiversity in the face of climate change.

The aim of this study is to investigate the significance of nonpolar functional groups in the surface orientation-dependent adsorption of natural and synthetic antifreeze proteins (AFPs) on ice. We investigate using nanoliter osmometry, ice etching, and circular dichroism spectroscopy a series of nine designed α-helical peptides to probe the nature of their selectivity between the bipyramidal {201} and the secondary prismatic {21̅0} faces of ice, identified earlier as the preferred faces for adsorption of winter flounder (WF) and shorthorn sculpin type I AFPs, respectively. Complementarities between the AFP’s surface features, comprised chiefly of nonpolar groups, and the well-defined sites on ice surface, allow close contact. Because our experimental studies demonstrate that the function of AFPs relies on participation of both polar and nonpolar residues in the ice surface adsorption, we carry out computational modeling to explore both kinds of contacts at the ice surface. On the basis of results of semiempirical quantum mechanical calculations of the WF AFP/ice system, we propose and discuss a new model for the binding of WF AFP to the {201} surface of ice, in a groove formed between {21̅0} and {011} facets. [ABSTRACT FROM AUTHOR]

Background and Aims It has been proposed that having too much DNA may carry physiological consequences for plants. The strong correlation between DNA content, cell size and cell division rate could lead to predictable morphological variation in plants, including a negative relationship with leaf mass per unit area (LMA). In addition, the possible increased demand for resources in species with high DNA content may have downstream effects on maximal metabolic efficiency, including decreased metabolic rates. Methods Tests were made for genome size-dependent variation in LMA and metabolic rates (mass-based photosynthetic rate and dark respiration rate) using our own measurements and data from a plant functional trait database (Glopnet). These associations were tested using two metrics of genome size: bulk DNA amount (2C DNA) and monoploid genome size (1Cx DNA). The data were analysed using an evolutionary framework that included a regression analysis and independent contrasts using a phylogenetic tree with estimates of molecular diversification times. A contribution index for the LMA data set was also calculated to determine which divergences have the greatest influence on the relationship between genome size and LMA. Key Results and Conclusions A significant negative association was found between bulk DNA amount and LMA in angiosperms. This was primarily a result of influential divergences that may represent early shifts in growth form. However, divergences in bulk DNA amount were positively associated with divergences in LMA, suggesting that the relationship may be indirect and mediated through other traits directly related to genome size. There was a significant negative association between genome size and metabolic rates that was driven by a basal divergence between angiosperms and gymnosperms; no significant independent contrast results were found. Therefore, it is concluded that genome size-dependent constraints acting on metabolic efficiency may not exist within seed plants. [ABSTRACT FROM AUTHOR]