Ocean chemical and physical conditions are changing. Here we show decadal variability and recent acceleration of surface warming, salinification, deoxygenation, carbon dioxide (CO
2
) and ...acidification in the subtropical North Atlantic Ocean (Bermuda Atlantic Time-series Study site; 1980s to present). Surface temperatures and salinity exhibited interdecadal variability, increased by ~0.85 °C (with recent warming of 1.2 °C) and 0.12, respectively, while dissolved oxygen levels decreased by ~8% (~2% per decade). Concurrently, seawater DIC,
f
CO
2
(fugacity of CO
2
) and anthropogenic CO
2
increased by ~8%, 22%, and 72% respectively. The winter versus summer
f
CO
2
difference increased by 4 to 8 µatm decade
−1
due to seasonally divergent thermal and alkalinity changes. Ocean pH declined by 0.07 (~17% increase in acidity) and other acidification indicators by ~10%. Over the past nearly forty years, the highest increase in ocean CO
2
and ocean acidification occurred during decades of weakest atmospheric CO
2
growth and vice versa.
Carbon dioxide concentrations and ocean acidification in the subtropical surface Atlantic Ocean increased fastest during the two decades of weakest atmospheric carbon dioxide level increases, according to an analysis of observations at two open-ocean hydrographic stations.
Ocean ecosystem models predict that warming and increased surface ocean stratification will trigger a series of ecosystem events, reducing the biological export of particulate carbon to the ocean ...interior. We present a nearly three-decade time series from the open ocean that documents a biological response to ocean warming and nutrient reductions wherein particulate carbon export is maintained, counter to expectations. Carbon export is maintained through a combination of phytoplankton community change to favor cyanobacteria with high cellular carbon-to-phosphorus ratios and enhanced shallow phosphorus recycling leading to increased nutrient use efficiency. These results suggest that surface ocean ecosystems may be more responsive and adapt more rapidly to changes in the hydrographic system than is currently envisioned in earth ecosystem models, with positive consequences for ocean carbon uptake.
Pulmonary arterial hypertension in association with connective tissue disease (CTD-PAH) has historically had a poor prognosis, with a 1-year survival rate among patients with systemic ...sclerosis-associated pulmonary arterial hypertension (SSc-PAH) of 45%. However, more therapies have become available.
To investigate the survival and characteristics of all patients diagnosed with CTD-PAH in the U.K. pulmonary hypertension service.
National registry of all incident cases of CTD-PAH diagnosed consecutively between January 2001 and June 2006.
Patients with CTD-PAH (429; 73% SSc-PAH) were diagnosed by a catheter-based approach. One- and 3-year survival rates were 78 and 47% for patients with isolated SSc-PAH. Survival was worse for those with respiratory disease-associated SSc-PAH (3-yr survival, 28%; P = 0.005) whereas survival among patients with exercise-induced SSc-PAH was superior (3-yr survival, 86%; P = < 0.001). Age, sex, mixed venous oxygen saturation, and World Health Organization functional class were independent predictors of survival in isolated SSc-PAH. Nineteen percent of patients with exercise-induced SSc-PAH and 39% of patients with isolated SSc-PAH who were in functional classes I and II had evidence of disease progression. The prevalence of diagnosed SSc-PAH is 2.93 per 1 million. The 3-year survival rate of 75% for those with pulmonary arterial hypertension associated with systemic lupus erythematosus (SLE-PAH) was significantly better than that for patients with SSc-PAH (P = 0.01).
Survival of patients with SSc-PAH in the modern treatment era is better than in historical series. A significant proportion of patients with mild functional impairment or exercise-induced SSc-PAH have evidence of disease progression. Survival of patients with respiratory disease-associated pulmonary hypertension is inferior. SLE-PAH has a better prognosis than SSc-PAH.
Since the first samples drawn from the Sargasso Sea were analyzed nearly 70 years ago, waters in this subtropical region of the North Atlantic Ocean have grown warmer (+1.2°C) and saltier (+0.11), ...lost oxygen (8% over past 40 years), and gained anthropogenic carbon dioxide (CO2; 72% increase), and in the recent decade, these changes have accelerated (Bates and Johnson, 2020). We present the findings from shipboard observations in the deep Sargasso Sea at Hydrostation S and the Bermuda Atlantic Time Series, two time-series stations maintained by the Bermuda Institute of Ocean Sciences, which is situated near the center of the North Atlantic Ocean subtropical gyre. Oceanographic data collected at these two stations provide critical information about ocean changes taking place and what these changes might mean to the future of our planet.
Urban fragmentation can reduce gene flow that isolates populations, reduces genetic diversity and increases population differentiation, all of which have negative conservation implications. ...Alternatively, gene flow may actually be increased among urban areas consistent with an urban facilitation model. In fact, urban adapter pests are able to thrive in the urban environment and may be experiencing human‐mediated transport. Here, we used social network theory with a population genetic approach to investigate the impact of urbanization on genetic connectivity in the Western black widow spider, as an urban pest model of human health concern. We collected genomewide single nucleotide polymorphism variation from mitochondrial and nuclear double‐digest RAD (ddRAD) sequence data sets from 210 individuals sampled from 11 urban and 10 nonurban locales across its distribution of the Western United States. From urban and nonurban contrasts of population, phylogenetic, and network analyses, urban locales have higher within‐population genetic diversity, lower between‐population genetic differentiation and higher estimates of genetic connectivity. Social network analyses show that urban locales not only have more connections, but can act as hubs that drive connectivity among nonurban locales, which show signatures of historical isolation. These results are consistent with an urban facilitation model of gene flow and demonstrate the importance of sampling multiple cities and markers to identify the role that urbanization has had on larger spatial scales. As the urban landscape continues to grow, this approach will help determine what factors influence the spread and adaptation of pests, like the venomous black widow spider, in building policies for human and biodiversity health.
Ocean physical and biogeochemical conditions are rapidly changing over time. Forty years of observations from 1983 to 2023 collected at the Bermuda Atlantic Time-series Study (BATS) site near Bermuda ...in the North Atlantic Ocean shows continuing trends of surface warming, increase in salinity, loss of dissolved oxygen (DO), increase in carbon dioxide (CO
2
), and ocean acidification (OA) effects. Over this period, the ocean has warmed by about +1°C, increased in salinity by +0.136, and lost DO by 12.5 µmol kg
−1
or ~6%. Since the 1980s, ocean dissolved inorganic carbon (DIC), total alkalinity (TA), a tracer of anthropogenic CO
2
(C
TrOCA
), and fugacities/partial pressures of CO
2
(i.e.,
f
CO
2
and
p
CO
2
) have continued to increase substantially, with no evidence of a reduction in the rates of change over time. Contemporaneously, ocean pH has decreased by ~0.1 pH units with ocean acidity (i.e., H
+
) increasing by >30%, and the saturation states of calcium carbonate minerals (Ω
calcite
and Ω
aragonite
) have decreased. These OA indicators show that the chemical conditions for calcification have become less favorable over the past 40 years. Updating of data and trends at the BATS site show how ocean chemistry of the 2020s is now outside the range observed in the 1980s, and how essential these data are for predicting the response of ocean chemistry and marine ecosystems to future shifting earth and ocean conditions.
Climate warming likely drives ocean deoxygenation, but models still cannot fully explain observed declines in oxygen. One unconstrained parameter is the oxygen demand per carbon respired for complete ...remineralization of organic matter (i.e., the total respiration quotient, rΣ‐O2:C). Here, we tested if rΣ‐O2:C declined with depth by quantifying suspended concentrations of particulate organic carbon (POC), particulate organic nitrogen (PON), particulate organic phosphorus (POP), particulate chemical oxygen demand (PCOD), and total oxygen demand (Σ‐O2 = PCOD + 2PON) down to a depth of 1,000 m in the Sargasso Sea. The respiration quotient (r‐O2:C = PCOD:POC) and total respiration quotient (rΣ‐O2:C = Σ‐O2:POC) declined with depth in the euphotic zone, but increased vertically in the disphotic zone. C:N and rΣ‐O2:N changed with depth, but surface values were similar to values at 1,000 m. C:P, N:P, and rΣ‐O2:P mostly decreased with depth. We hypothesize that rΣ‐O2:C is linked to multiple environmental factors that change with depth, such as phytoplankton community structure and the preferential production/removal of biomolecules. Using a global model, we show that the global distribution of dissolved oxygen is equally sensitive to r‐O2:C varying between surface biomes versus vertically during remineralization. Additionally, adjusting the model's r‐O2:C with depth to match our observations resulted in less dissolved oxygen throughout the upper ocean. Most of this loss occurred in the tropical Pacific thermocline, where oxygen models underestimate deoxygenation the most. This study aims to improve our understanding of biological oxygen demand as warming‐induced deoxygenation continues.
Plain Language Summary
Rising ocean temperatures are likely causing the observed decline of dissolved oxygen below the ocean surface. This continued oxygen loss threatens the survival of many marine animals. Currently, global models cannot fully explain the observed rate of oxygen loss with warming. One missing component could be variance in the respiration quotient, the ratio of oxygen consumed per organic carbon respired during microbial respiration. However, the respiration quotient has yet to be estimated at different depths by directly measuring the chemical composition of organic matter. Here, we used direct measurements to find that the respiration quotient varied with depth in the Atlantic Ocean. Therefore, the respiration quotient at the surface should not represent values at deeper depths. In addition, we used a global model to find that the respiration quotient mostly affects oxygen in the tropical Pacific Ocean, where unexplained oxygen loss is the highest. Thus, more extensive data on the respiration quotient may significantly improve global models.
Key Points
The respiration quotient of particulate organic matter varied with depth
Elemental ratios of particulate organic matter deviated from Redfield proportions at all depths
The increase in the respiration quotient with depth may account for some previously unexplained oxygen loss
To identify multiple sclerosis (MS) susceptibility loci, we conducted a genome-wide association study (GWAS) in 1,618 cases and used shared data for 3,413 controls. We performed replication in an ...independent set of 2,256 cases and 2,310 controls, for a total of 3,874 cases and 5,723 controls. We identified risk-associated SNPs on chromosome 12q13-14 (rs703842, P = 5.4 × 10−11; rs10876994, P = 2.7 × 10−10; rs12368653, P = 1.0 × 10−7) and upstream of CD40 on chromosome 20q13 (rs6074022, P = 1.3 × 10−7; rs1569723, P = 2.9 × 10−7). Both loci are also associated with other autoimmune diseases. We also replicated several known MS associations (HLA-DR15, P = 7.0 × 10−184; CD58, P = 9.6 × 10−8; EVI5-RPL5, P = 2.5 × 10−6; IL2RA, P = 7.4 × 10−6; CLEC16A, P = 1.1 × 10−4; IL7R, P = 1.3 × 10−3; TYK2, P = 3.5 × 10−3) and observed a statistical interaction between SNPs in EVI5-RPL5 and HLA-DR15 (P = 0.001).
Abstract
Background
In addition to the established association between general obesity and breast cancer risk, central obesity and circulating fasting insulin and glucose have been linked to the ...development of this common malignancy. Findings from previous studies, however, have been inconsistent, and the nature of the associations is unclear.
Methods
We conducted Mendelian randomization analyses to evaluate the association of breast cancer risk, using genetic instruments, with fasting insulin, fasting glucose, 2-h glucose, body mass index (BMI) and BMI-adjusted waist-hip-ratio (WHRadj BMI). We first confirmed the association of these instruments with type 2 diabetes risk in a large diabetes genome-wide association study consortium. We then investigated their associations with breast cancer risk using individual-level data obtained from 98 842 cases and 83 464 controls of European descent in the Breast Cancer Association Consortium.
Results
All sets of instruments were associated with risk of type 2 diabetes. Associations with breast cancer risk were found for genetically predicted fasting insulin odds ratio (OR) = 1.71 per standard deviation (SD) increase, 95% confidence interval (CI) = 1.26-2.31, p = 5.09 × 10–4, 2-h glucose (OR = 1.80 per SD increase, 95% CI = 1.3 0-2.49, p = 4.02 × 10–4), BMI (OR = 0.70 per 5-unit increase, 95% CI = 0.65-0.76, p = 5.05 × 10–19) and WHRadj BMI (OR = 0.85, 95% CI = 0.79-0.91, p = 9.22 × 10–6). Stratified analyses showed that genetically predicted fasting insulin was more closely related to risk of estrogen-receptor ER-positive cancer, whereas the associations with instruments of 2-h glucose, BMI and WHRadj BMI were consistent regardless of age, menopausal status, estrogen receptor status and family history of breast cancer.
Conclusions
We confirmed the previously reported inverse association of genetically predicted BMI with breast cancer risk, and showed a positive association of genetically predicted fasting insulin and 2-h glucose and an inverse association of WHRadj BMI with breast cancer risk. Our study suggests that genetically determined obesity and glucose/insulin-related traits have an important role in the aetiology of breast cancer.
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