The transfer of photosynthetically produced organic carbon from surface to mesopelagic waters draws carbon dioxide from the atmosphere. However, current observation-based estimates disagree on the strength of this biological carbon pump (BCP). Earth system models (ESMs) also exhibit a large spread of BCP estimates, indicating limited representations of the known carbon export pathways.
View Article and Find Full Text PDFAims: To discuss the advantages and limitation of the different pelvic floor muscle (PFM) dynamometers available, both in research and industry, and to present the extent of variation between them in terms of structure, functioning, psychometric properties, and assessment procedures.
Methods: We identified relevant studies from four databases (MEDLINE, Compendex, Web of Science, and Derwent Innovations Index) up to December 2020 using terms related to dynamometry and PFM. In addition, we conducted a hand search of the bibliographies of all relevant reports.
Climate-driven depletion of ocean oxygen strongly impacts the global cycles of carbon and nutrients as well as the survival of many animal species. One of the main uncertainties in predicting changes to marine oxygen levels is the regulation of the biological respiration demand associated with the biological pump. Derived from the Redfield ratio, the molar ratio of oxygen to organic carbon consumed during respiration (i.
View Article and Find Full Text PDFUncertainty in the global patterns of marine nitrogen fixation limits our understanding of the response of the ocean's nitrogen and carbon cycles to environmental change. The geographical distribution of and ecological controls on nitrogen fixation are difficult to constrain with limited in situ measurements. Here we present convergent estimates of nitrogen fixation from an inverse biogeochemical and a prognostic ocean model.
View Article and Find Full Text PDFClimate change projections to the year 2100 may miss physical-biogeochemical feedbacks that emerge later from the cumulative effects of climate warming. In a coupled climate simulation to the year 2300, the westerly winds strengthen and shift poleward, surface waters warm, and sea ice disappears, leading to intense nutrient trapping in the Southern Ocean. The trapping drives a global-scale nutrient redistribution, with net transfer to the deep ocean.
View Article and Find Full Text PDFThe ocean is the largest sink for anthropogenic carbon dioxide (CO), having absorbed roughly 40 per cent of CO emissions since the beginning of the industrial era. Recent data show that oceanic CO uptake rates have been growing over the past decade, reversing a trend of stagnant or declining carbon uptake during the 1990s. Here we show that ocean circulation variability is the primary driver of these changes in oceanic CO uptake over the past several decades.
View Article and Find Full Text PDFDominant climatic factors controlling the lifetime peak intensity of typhoons are determined from six decades of Pacific typhoon data. We find that upper ocean temperatures in the low-latitude northwestern Pacific (LLNWP) and sea surface temperatures in the central equatorial Pacific control the seasonal average lifetime peak intensity by setting the rate and duration of typhoon intensification, respectively. An anomalously strong LLNWP upper ocean warming has favored increased intensification rates and led to unprecedentedly high average typhoon intensity during the recent global warming hiatus period, despite a reduction in intensification duration tied to the central equatorial Pacific surface cooling.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
September 2013
Tropical cyclones have been hypothesized to influence climate by pumping heat into the ocean, but a direct measure of this warming effect is still lacking. We quantified cyclone-induced ocean warming by directly monitoring the thermal expansion of water in the wake of cyclones, using satellite-based sea surface height data that provide a unique way of tracking the changes in ocean heat content on seasonal and longer timescales. We find that the long-term effect of cyclones is to warm the ocean at a rate of 0.
View Article and Find Full Text PDFSurface westerly winds in the Southern Hemisphere have intensified over the past few decades, primarily in response to the formation of the Antarctic ozone hole, and there is intense debate on the impact of this on the ocean's circulation and uptake and redistribution of atmospheric gases. We used measurements of chlorofluorocarbon-12 (CFC-12) made in the southern oceans in the early 1990s and mid- to late 2000s to examine changes in ocean ventilation. Our analysis of the CFC-12 data reveals a decrease in the age of subtropical subantarctic mode waters and an increase in the age of circumpolar deep waters, suggesting that the formation of the Antarctic ozone hole has caused large-scale coherent changes in the ventilation of the southern oceans.
View Article and Find Full Text PDFBackground: The objectives of the study were to characterize and compare the cognitive profile and natural evolution of patients presenting late-onset psychotic symptoms (LOPS: onset ≥ 50 years old) to those of elderly patients (≥ 50 years old) with life-long/early-onset schizophrenia (EOS: onset <40 years old).
Methods: Neuropsychological profiles of 15 LOPS patients were compared to those of 17 elderly EOS patients and to those of two control groups (n = 11/group). The evolution of the two patient groups was compared using an independent diagnostic consensual procedure involving a geriatric psychiatry physician/clinician and a neuropsychologist blinded to the initial psychiatric diagnosis.
In order to expand our understanding of the diversity and biogeography of Prochlorococcus ribotypes, we PCR-amplified, cloned and sequenced the 16S/23S rRNA ITS region from sites in the Atlantic and Pacific oceans. Ninety-three per cent of the ITS sequences could be assigned to existing Prochlorococcus clades, although many novel subclades were detected. We assigned the sequences to operational taxonomic units using a graduated scale of sequence identity from 80% to 99.
View Article and Find Full Text PDFBackground: Family practitioners take care of large numbers of seniors with increasingly complex mental health problems. Varying levels of input may be necessary from psychiatric consultants. This study examines patients'/family, family practitioners', and psychiatrists' perceptions of the bi-directional pathway between such primary care doctors and consultants.
View Article and Find Full Text PDFEvidence suggests that the pharmaceutical industry exerts a large influence on residents' education and practice. Yet existing guidelines by professional bodies do not cover the specifics of residents' interactions with the pharmaceutical industry. At the psychiatry residency program of the McGill University Health Center, the authors set out to systematically evaluate areas of concern for residents and to develop guidelines for use by residents during and outside their training.
View Article and Find Full Text PDFBackground: Delirium is common and often goes undetected in older patients admitted to medical services. It is associated with poor outcomes. We conducted a randomized clinical trial to determine whether systematic detection and multidisciplinary care of delirium in older patients admitted to a general medical service could reduce time to improvement in cognitive status.
View Article and Find Full Text PDFPsychiatr Clin North Am
September 2002
Persuasion, influence, and change are familiar domains in psychiatry. Frequently, therapists attempt to identify and understand the cognitions, affects, and perceptions their patients have developed or acquired and then, by a number of means, trigger therapeutic changes. Whereas they spend much work in the therapeutic setting attempting to delineate the mechanisms that produce such transformations and to influence change, physicians are often in a similar relationship with the pharmaceutical industry.
View Article and Find Full Text PDFBackground: Delirium has not been found to be a significant predictor of postdischarge mortality, but previous research has methodologic limitations including small sample sizes and inadequate control of confounding. This study aimed to determine the independent effects of presence of delirium, type of delirium (incident vs prevalent), and severity of delirium symptoms on 12-month mortality among older medical inpatients.
Methods: A prospective, observational study of 2 cohorts of medical inpatients was conducted with patients 65 years or older: 243 patients had prevalent or incident delirium, and 118 controls had no delirium.