Modeling North Pacific temperature and pressure changes from coastal tree-ring chronologies

Climate modeling using coastal tree-ring chronologies has yielded the first summer temperature reconstructions for coastal stations along the Gulf of Alaska and the Pacific Northwest. These land temperature reconstructions are strongly correlated with nearby sea surface temperatures, indicating large-scale ocean-atmospheric influences. Significant progress has also been made in modeling winter land temperatures and sea surface temperatures from coastal and shipboard stations. In addition to temperature, the pressure variability center over the central North Pacific Ocean (PAC), which is related to the strength and location of the Aleutian Low pressure system, could be extended using coastal tree rings

Climate Response of Larch and Birch Forests across an Elevational Transect and Hemisphere-Wide Comparisons, Kamchatka Peninsula, Russian Far East

Kamchatka’s forests span across the peninsula’s diverse topography and provide a wide range of physiographic and elevational settings that can be used to investigate how forests are responding to climate change and to anticipate future response. Birch (Betula ermanii Cham.) and larch (Larix gmelinii (Rupr.) Kuzen) were sampled at eight new sites and together with previous collections were compared with monthly temperature and precipitation records to identify their climate response. Comparisons show that tree-ring widths in both species are primarily influenced by May through August temperatures of the current growth year, and that there is a general increase in temperature sensitivity with altitude. The ring-width data for each species were also combined into regional chronologies. The resulting composite larch chronology shows a strong resemblance to a Northern Hemisphere (NH) tree-ring based temperature reconstruction with the larch series tracking NH temperatures closely through the past 300 years. The composite birch ring-width series more closely reflects the Pacific regional coastal late summer temperatures. These new data improve our understanding of the response of forests to climate and show the low frequency warming noted in other, more continental records from high latitudes of the Northern Hemisphere. Also evident in the ring-width record is that the larch and birch forests continue to track the strong warming of interior Kamchatka

Tree-ring investigations into changing climatic responses of yellow-cedar, Glacier Bay, Alaska

Yellow-cedar (Callitropsis nootkatensis (D. Don) à–rsted ex D.P. Little) is in a century-long decline coinciding with the end of the Little Ice Age (LIA). The leading hypothesis explaining this decline is a decrease in insulating snowpack due to warming and increased susceptibility to damaging frosts in the root zone. A ring-width series from yellow-cedar on Excursion Ridge (260 m a.s.l.) in Glacier Bay National Park and Preserve, Alaska, and another from trees on Pleasant Island (150 m a.s.l.) in the Tongass National Forest in Icy Strait were compared with regional monthly temperature and precipitation data from Sitka, Alaska, to investigate the changing growth response to temperature at these sites. Comparisons with monthly temperatures from 1832 to 1876 during the end of the Little Ice Age show that the high-elevation Excursion Ridge and the low-elevation Pleasant Island sites strongly favored warmer January through July temperatures. Both tree populations have markedly changed their response from a positive to a strong negative correlation with January through July temperatures since 1950. This strong negative response to warming by the yellow-cedar together with a positive relationship with total March and April precipitation suggests that these yellow-cedar sites may be susceptible to decline. Furthermore, these analyses are consistent with the hypothesis that the yellow-cedar decline is linked to decreased snowpack

Managing lifestyle change to reduce coronary risk: a synthesis of qualitative research on peoples’ experiences

Background Coronary heart disease is an incurable condition. The only approach known to slow its progression is healthy lifestyle change and concordance with cardio-protective medicines. Few people fully succeed in these daily activities so potential health improvements are not fully realised. Little is known about peoples’ experiences of managing lifestyle change. The aim of this study was to synthesise qualitative research to explain how participants make lifestyle change after a cardiac event and explore this within the wider illness experience. Methods A qualitative synthesis was conducted drawing upon the principles of meta-ethnography. Qualitative studies were identified through a systematic search of 7 databases using explicit criteria. Key concepts were identified and translated across studies. Findings were discussed and diagrammed during a series of audiotaped meetings. Results The final synthesis is grounded in findings from 27 studies, with over 500 participants (56% male) across 8 countries. All participants experienced a change in their self-identity from what was ‘familiar’ to ‘unfamiliar’. The transition process involved ‘finding new limits and a life worth living’ , ‘finding support for self’ and ‘finding a new normal’. Analyses of these concepts led to the generation of a third order construct, namely an ongoing process of ‘reassessing past, present and future lives’ as participants considered their changed identity. Participants experienced a strong urge to get back to ‘normal’. Support from family and friends could enable or constrain life change and lifestyle changes. Lifestyle change was but one small part of a wider ‘life’ change that occurred. Conclusions The final synthesis presents an interpretation, not evident in the primary studies, of a person-centred model to explain how lifestyle change is situated within ‘wider’ life changes. The magnitude of individual responses to a changed health status varied. Participants experienced distress as their notion of self identity shifted and emotions that reflected the various stages of the grief process were evident in participants’ accounts. The process of self-managing lifestyle took place through experiential learning; the level of engagement with lifestyle change reflected an individual’s unique view of the balance needed to manage ‘realistic change’ whilst leading to a life that was perceived as ‘worth living’. Findings highlight the importance of providing person centred care that aligns with both psychological and physical dimensions of recovery which are inextricably linked

Yellow-cedar blue intensity tree ring chronologies as records of climate, Juneau, Alaska, USA

This work was supported by the National Science Foundation’s Paleoclimatic Perspectives on Climatic Change (P2C2) Program grant nos. AGS 1159430, AGS 1502186, AGS 1502150, and PLR 15-04134 and by the Keck Geology Consortium funded by The National Science Foundation under Grant No. (NSF-REU #1358987).This is the first study to generate and analyze the climate signal in Blue Intensity (BI) tree-ring chronologies from Alaskan yellow-cedar (Callitropsis nootkatensis D. Don; Oerst. ex D.P. Little). The latewood BI chronology shows a much stronger temperature sensitivity than ring-widths (RW), and thus can provide information on past climate. The well-replicated BI chronology exhibits a positive January-August average maximum temperature signal for 1900-1975, after which it loses temperature sensitivity following the 1976/77 shift in northeast Pacific climate. The positive temperature response appears to recover and remains strong for the most recent decades although the coming years will continue to test this observation. This temporary loss of temperature sensitivity from about 1976 to 1999 is not evident in RW or in a change in forest health, but is consistent with prior work linking cedar decline to warming. A confounding factor is the uncertain influence of a shift in color variation from the heartwood/sapwood boundary. Future expansion of the yellow-cedar BI network and further investigation of the influence of the heartwood/sapwood transitions in the BI signal will lead to a better understanding of the utility of this species as a climate proxy.PostprintPeer reviewe

Timing and Potential Causes of 19th-Century Glacier Advances in Coastal Alaska Based on Tree-Ring Dating and Historical Accounts

The Little Ice Age (LIA), ca. CE 1250–1850, was a cold period of global extent, with the nature and timing of reduced temperatures varying by region. The Gulf of Alaska (GOA) is a key location to study the climatic drivers of glacier fluctuations during the LIA because dendrochronological techniques can provide precise ages of ice advances and retreats. Here, we use dendrochronology to date the most recent advance of La Perouse Glacier in the Fairweather Range of Southeast Alaska. After maintaining a relatively contracted state since at least CE 1200, La Perouse advanced to its maximum LIA position between CE 1850 and 1895. Like many other glaciers bordering the GOA, the La Perouse Glacier reached this maximum position relatively late in the LIA compared with glaciers in other regions. This is curious because reconstructions of paleoclimate in the GOA region indicate the 19th century was not the coldest period of the LIA. Using newly available paleoclimate data, we hypothesize that a combination of moderately cool summers accompanying the Dalton Solar Minimum and exceptionally snowy winters associated with a strengthened Aleutian Low could have caused these relatively late LIA advances. Such a scenario implies that winter climate processes, which are heavily influenced by ocean-atmospheric variability in the North Pacific region, have modulated these coastal glaciers’ sensitivity to shifts in summer temperatures

DeLLITE Depression in late life: an intervention trial of exercise. Design and recruitment of a randomised controlled trial

<p>Abstract</p> <p>Background</p> <p>Physical activity shows potential in combating the poor outcomes associated with depression in older people. Meta-analyses show gaps in the research with poor trial design compromising certainty in conclusions and few programmes showing sustained effects.</p> <p>Methods/design</p> <p>The Depression in Late Life: an Intervention Trial of Exercise (DeLLITE) is a 12 month randomised controlled trial of a physical activity intervention to increase functional status in people aged 75 years and older with depressive symptoms. The intervention involves an individualised activity programme based on goal setting and progression of difficulty of activities delivered by a trained nurse during 8 home visits over 6 months. The control group received time matched home visits to discuss social contacts and networks. Baseline, 6 and 12 months measures were assessed in face to face visits with the primary outcome being functional status (SPPB, NEADL). Secondary outcomes include depressive symptoms (Geriatric Depression Scale), quality of life (SF-36), physical activity (AHS Physical Activity Questionnaire) and falls (self report).</p> <p>Discussion</p> <p>Due to report in 2008 the DeLLITE study has recruited 70% of those eligible and tests the efficacy of a home based, goal setting physical activity programme in improving function, mood and quality of life in older people with depressive symptomatology. If successful in improving function and mood this trial could prove for the first time that there are long term health benefit of physical activity, independent of social activity, in this high risk group who consume excess health related costs.</p> <p>Trial registration</p> <p>Australian and New Zealand Clinical Trials Register ACTRN12605000475640</p

The quality of care delivered to residents in long-term care in Australia: an indicator-based review of resident records (CareTrack Aged study)

Background: This study estimated the prevalence of evidence-based care received by a population-based sample of Australian residents in long-term care (LTC) aged ≥ 65 years in 2021, measured by adherence to clinical practice guideline (CPG) recommendations. Methods: Sixteen conditions/processes of care amendable to estimating evidence-based care at a population level were identified from prevalence data and CPGs. Candidate recommendations (n = 5609) were extracted from 139 CPGs which were converted to indicators. National experts in each condition rated the indicators via the RAND-UCLA Delphi process. For the 16 conditions, 236 evidence-based care indicators were ratified. A multi-stage sampling of LTC facilities and residents was undertaken. Trained aged-care nurses then undertook manual structured record reviews of care delivered between 1 March and 31 May 2021 (our record review period) to assess adherence with the indicators. Results: Care received by 294 residents with 27,585 care encounters in 25 LTC facilities was evaluated. Residents received care for one to thirteen separate clinical conditions/processes of care (median = 10, mean = 9.7). Adherence to evidence-based care indicators was estimated at 53.2% (95% CI: 48.6, 57.7) ranging from a high of 81.3% (95% CI: 75.6, 86.3) for Bladder and Bowel to a low of 12.2% (95% CI: 1.6, 36.8) for Depression. Six conditions (skin integrity, end-of-life care, infection, sleep, medication, and depression) had less than 50% adherence with indicators. Conclusions: This is the first study of adherence to evidence-based care for people in LTC using multiple conditions and a standardised method. Vulnerable older people are not receiving evidence-based care for many physical problems, nor care to support their mental health nor for end-of-life care. The six conditions in which adherence with indicators was less than 50% could be the focus of improvement efforts

Whole-genome sequencing reveals host factors underlying critical COVID-19

Critical COVID-19 is caused by immune-mediated inflammatory lung injury. Host genetic variation influences the development of illness requiring critical care1 or hospitalization2–4 after infection with SARS-CoV-2. The GenOMICC (Genetics of Mortality in Critical Care) study enables the comparison of genomes from individuals who are critically ill with those of population controls to find underlying disease mechanisms. Here we use whole-genome sequencing in 7,491 critically ill individuals compared with 48,400 controls to discover and replicate 23 independent variants that significantly predispose to critical COVID-19. We identify 16 new independent associations, including variants within genes that are involved in interferon signalling (IL10RB and PLSCR1), leucocyte differentiation (BCL11A) and blood-type antigen secretor status (FUT2). Using transcriptome-wide association and colocalization to infer the effect of gene expression on disease severity, we find evidence that implicates multiple genes—including reduced expression of a membrane flippase (ATP11A), and increased expression of a mucin (MUC1)—in critical disease. Mendelian randomization provides evidence in support of causal roles for myeloid cell adhesion molecules (SELE, ICAM5 and CD209) and the coagulation factor F8, all of which are potentially druggable targets. Our results are broadly consistent with a multi-component model of COVID-19 pathophysiology, in which at least two distinct mechanisms can predispose to life-threatening disease: failure to control viral replication; or an enhanced tendency towards pulmonary inflammation and intravascular coagulation. We show that comparison between cases of critical illness and population controls is highly efficient for the detection of therapeutically relevant mechanisms of disease

Genetic mechanisms of critical illness in COVID-19.

Host-mediated lung inflammation is present1, and drives mortality2, in the critical illness caused by coronavirus disease 2019 (COVID-19). Host genetic variants associated with critical illness may identify mechanistic targets for therapeutic development3. Here we report the results of the GenOMICC (Genetics Of Mortality In Critical Care) genome-wide association study in 2,244 critically ill patients with COVID-19 from 208 UK intensive care units. We have identified and replicated the following new genome-wide significant associations: on chromosome 12q24.13 (rs10735079, P = 1.65 × 10-8) in a gene cluster that encodes antiviral restriction enzyme activators (OAS1, OAS2 and OAS3); on chromosome 19p13.2 (rs74956615, P = 2.3 × 10-8) near the gene that encodes tyrosine kinase 2 (TYK2); on chromosome 19p13.3 (rs2109069, P = 3.98 ×  10-12) within the gene that encodes dipeptidyl peptidase 9 (DPP9); and on chromosome 21q22.1 (rs2236757, P = 4.99 × 10-8) in the interferon receptor gene IFNAR2. We identified potential targets for repurposing of licensed medications: using Mendelian randomization, we found evidence that low expression of IFNAR2, or high expression of TYK2, are associated with life-threatening disease; and transcriptome-wide association in lung tissue revealed that high expression of the monocyte-macrophage chemotactic receptor CCR2 is associated with severe COVID-19. Our results identify robust genetic signals relating to key host antiviral defence mechanisms and mediators of inflammatory organ damage in COVID-19. Both mechanisms may be amenable to targeted treatment with existing drugs. However, large-scale randomized clinical trials will be essential before any change to clinical practice