568 research outputs found
A 3,500-year tree-ring record of annual precipitation on the northeastern Tibetan Plateau
An annually resolved and absolutely dated ring-width chronology spanning 4,500 y has been constructed using subfossil, archaeological, and living-tree juniper samples from the northeastern Tibetan Plateau. The chronology represents changing mean annual precipitation and is most reliable after 1500 B.C. Reconstructed precipitation for this period displays a trend toward more moist conditions: the last 10-, 25-, and 50-y periods all appear to be the wettest in at least three and a half millennia. Notable historical dry periods occurred in the 4th century BCE and in the second half of the 15th century CE. The driest individual year reconstructed (since 1500 B.C.) is 1048 B.C., whereas the wettest is 2010. Precipitation variability in this region appears not to be associated with inferred changes in Asian monsoon intensity during recent millennia. The chronology displays a statistical association with the multidecadal and longer-term variability of reconstructed mean Northern Hemisphere temperatures over the last two millennia. This suggests that any further large-scale warming might be associated with even greater moisture supply in this region
Alla! Alla!
Ä abra ta’ poeżiji u proża li tinkludi: Il-Għanja tal-Għid ta’ Sajdun – Nofs-inhar Sajfi ta’ Rosario Briffa – Min kien Jusef ta’ G. B. – L-Hinn min-Natura Hemm Alla! ta’ Dun Karm – Il-Flus tal-Ħares ta’ T. Z. – Alla! Alla! ta’ C. M. B.N/
High In Situ Repeatability of Behaviour Indicates Animal Personality in the Beadlet Anemone Actinia equina (Cnidaria)
‘Animal personality’ means that individuals differ from one another in either single behaviours or suites of related behaviours in a way that is consistent over time. It is usually assumed that such consistent individual differences in behaviour are driven by variation in how individuals respond to information about their environment, rather than by differences in external factors such as variation in microhabitat. Since behavioural variation is ubiquitous in nature we might expect ‘animal personality’ to be present in diverse taxa, including animals with relatively simple nervous systems. We investigated in situ startle responses in a sea anemone, Actinia equina, to determine whether personalities might be present in this example of an animal with a simple nervous system. We found very high levels of repeatability among individuals that were re-identified in the same locations over a three week sampling period. In a subset of the data, where we used tide-pool temperature measurements to control for a key element of variation in microhabitat, these high levels of repeatability remained. Although a range of other consistent differences in micro-habitat features could have contributed to consistent differences between the behaviour of individuals, these data suggest the presence of animal personality in A. equina. Rather than being restricted to certain groups, personality may be a general feature of animals and may be particularly pronounced in species with simple nervous systems
The nature of the charge density waves in under-doped YBaCuO revealed by X-ray measurements of the ionic displacements
All underdoped high-temperature cuprate superconductors appear to exhibit
charge density wave (CDW) order, but both the underlying symmetry breaking and
the origin of the CDW remain unclear. We use X-ray diffraction to determine the
microscopic structure of the CDW in an archetypical cuprate
YBaCuO at its superconducting transition temperature Tc ~ 60
K. We find that the CDWs present in this material break the mirror symmetry of
the CuO2 bilayers. The ionic displacements in a CDW have two components: one
perpendicular to the CuO planes, and another parallel to these planes,
which is out of phase with the first. The largest displacements are those of
the planar oxygen atoms and are perpendicular to the CuO planes. Our
results allow many electronic properties of the underdoped cuprates to be
understood. For instance, the CDW will lead to local variations in the doping
(or electronic structure) giving an explicit explanation of the appearance of
density-wave states with broken symmetry in scanning tunnelling microscopy
(STM) and soft X-ray measurements
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Evaluation of long-term clinical and health service outcomes following coronary artery revascularisation in Western Australia (WACARP): a population-based cohort study protocol
Introduction: Coronary artery bypass grafting (CABG) and percutaneous coronary interventions (PCI) are procedures commonly performed on patients with significant obstructive coronary artery disease to relieve symptoms of ischaemia, improve survival or both. Although the efficacy of both procedures at the individual level has been established, the impact of advances in coronary artery revascularisation procedures (CARP) on long-term outcomes and cost-effectiveness at the population level are yet to be assessed. Our aim is to evaluate a minimum of 6-year outcomes and costs for the total population of patients who had CARP in Western Australia (WA) in 2000–2005. Methods and analysis This retrospective population cohort study will link clinical and administrative health data for a previously defined cohort including all patients in WA who had a CARP in the period 2000–2005. The cohort consists of 19 014 patients who had 21 175 procedures (15 429 PCI and 5746 CABG). We are now collecting a minimum of 6 years follow-up of morbidity and mortality data for the cohort using the WA Data Linkage System, clinical registries and hospital records, with 12 years follow-up for cases in the year 2000. Comparison of long-term outcomes for different CARP will be reported (PCI vs CABG; bare metal stents vs drug-eluting stents vs CABG). Cost-effectiveness analysis of CARP from the perspective of the healthcare sector will be performed using individual level cost data and average costs from Australian Refined Diagnosis Related Groups. Ethics and dissemination This study has received ethics approval from the University of Western Australia, the Western Australian Department of Health and all participating hospitals. Being a large population cohort study, approval included a waiver of informed consent. All findings will be presented at local, national and international healthcare/academic conferences and published in peer-reviewed journals
Socioeconomic Equity in the Receipt of In-Hospital Care and Outcomes in Australian Acute Coronary Syndrome Patients: The CONCORDANCE Registry
Background: Socioeconomic status (SES) is a social determinant of both health and receipt of health care services, but its impact is under-studied in acute coronary syndrome (ACS). The aim of this study was to examine the influence of SES on in-hospital care, and clinical events for patients presenting with an ACS to public hospitals in Australia. Methods: Data from 9064 ACS patient records were collected from 41 public hospitals nationwide from 2009 as part of the Cooperative National Registry of Acute Coronary Syndrome Care (CONCORDANCE) registry. For this analysis, we divided the cohort into four socioeconomic groups (based on postcode of usual residence) and compared the in-hospital care provided and clinical outcomes before and after adjustment for both patient clinical characteristics and hospital clustering. Results: Patients were divided into four SES groups (from the most to the least disadvantaged: 2042 (23%) vs. 2104 (23%) vs. 1994 (22%) vs. 2968 (32%)). Following adjustments for patient characteristics, there were no differences in the odds of receiving coronary angiogram, revascularisation, prescription of recommended medication, or referral to cardiac rehabilitation across the SES groups (p = 0.06, 0.69, 0.89 and 0.79, respectively). After adjustment for clinical characteristics, no associations were observed for in-hospital and cumulative death (p = 0.62 and p = 0.71, respectively). However, the most disadvantaged group were 37% more likely to have a major adverse cardiovascular event (MACE) than the least disadvantaged group (OR (95% CI): 1.37 (1.1, 1.71), p = 0.02) driven by incidence of in-hospital heart failure. Conclusions: Although there may be gaps in the delivery of care, this delivery of care does not differ by patient's SES. It is an encouraging affirmation that all patients in Australian public hospitals receive equal in-hospital care, and the likelihood of death is comparable between the SES groups
What football teaches us about researching complex health interventions
Football and healthcare are both complex adaptive systems. Alex Clark and colleagues wonder how and why football scores more highly when it comes to introducing interventions
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