Long-term Buffer Research Articles

Loneliness, perceived social support, and their changes predict medical adherence over 12 months among patients with coronary heart disease.

This study investigated whether changes in loneliness and perceived social support predicted medical adherence in patients with coronary heart disease (CHD) over 12 months. Moreover, short-term and long-term buffering effects of social support on the association between loneliness and medical adherence were systematically examined. A three-wave longitudinal study. Participants were 255 CHD patients with a mean age of 63 years. Medical adherence, loneliness, and perceived social support were assessed at baseline, 3 months, and 12 months. Hierarchical regression analyses were conducted to examine the influences of loneliness and social support as well as their changes on medical adherence over 12 months. Moderation analyses were performed to test buffering effects of baseline social support and its changes against loneliness and its changes, respectively. Changes in loneliness significantly predicted medical adherence at 12 months (β = -.23, p = .001) but not at 3 months (β = -.10, p = .142). Changes in social support predicted medical adherence at both 3 (β = .23, p = .002) and 12 months (β = .26, p = .001). Social support concurrently buffered the adverse impact of loneliness on medical adherence (B = .29, SE = .12, p = .020) at baseline but did not at 3 or 12 months (Bs = -.21 to .40, SEs = .12 to .30, ps = .177 to .847). Findings highlight the importance of monitoring loneliness and perceived social support continuously over time for CHD patients to promote medical adherence.

Telescopic Megafans on the High Plains, USA Were Signal Buffers in a Major Source-To-Sink System

Sediment routing systems transport sediment and environmental signals inefficiently. The storage and recycling of sediment buffers the responses of sedimentary systems to tectonic, climatic, and geomorphic changes. Long-term ( >106 a.) storage may occur in megafans—large, low-relief, hemiconical fluvial deposystems—but the behavior of these systems over such timescales is unclear. We examine late Neogene megafan deposits on the High Plains, USA that are stored in the catchment of the continental-scale Rocky Mountain-Gulf of Mexico source-to-sink system. Using high-resolution elevation data, we map numerous fluvial ridges (inverted channel relics) that can be differentiated into five, chronologically distinct groups. The oldest four groups comprise radial arrays with multiple channel divergences (avulsion nodes). The inferred fan apices and longitudinal intersection points are offset successively downgradient, indicating that fanhead entrenchment and fan-lobe deposition were approximately contemporaneous and strongly suggesting a telescopic morphology. The youngest group of channels, also the lowest in elevation, is confined to terraces along the modern valley of the South Platte River. We interpret this group as direct evidence for the abandonment of the megafan and the incision of the present valley. Uplift was the chief driving mechanism for early telescoping, but channel widening and uniform downcutting in the younger groups suggest that change in stream power was the primary driver of later telescoping and incision. The storage of sediment in the megafan effectively decoupled sources from downstream sinks. Some of this sediment was recycled during entrenchment, but much of it remains in storage as the Ogallala Group and Broadwater Formation. Emplacement of telescopic megafans should be considered as a long-term ( ≥106 years) buffer in other modern and ancient sediment routing systems.

Highly targeted stabilization and release behavior of hazardous substances in phosphogypsum

In this paper, an innovative method for highly targeted solidification/stabilization (S/S) of harmful substances in phosphogypsum (PG) was proposed. The release behavior of hazardous substances in PG after mixed reaction was explored using lime or carbide slag (CS) as alkaline regulator and then polyaluminium chloride (PAC), polyferric sulfate (PFS) and polyacrylamide (PAM) as highly targeted S/S agents. The experimental results show that lime has a long-term buffering effect on the pH of PG and a significant stabilizing effect on P, F and heavy metals. When more than 5 % lime was added, the leaching concentration of heavy metals was less than 0.1 mg/L. Moreover, PAM, PAC and PFS have remarkable S/S effects on P, F and heavy metals in the order of PAM > PFS > PAC. When the dosage of PAM was more than 5 %, the leaching concentration of P and F was less than 0.2 mg/L and 1 mg/L, respectively, and that of heavy metals tends to be 0 mg/L, indicating that PAM demonstrates a significant continuous S/S effect and thus provides a feasible pretreatment method for harmless filling, soil utilization and high value-added resource utilization of PG. The high targeted S/S technology of hazardous substances studied in this paper directly provides theoretical and data support for the harmless and resource-based treatment of large-scale solid waste PG produced, alleviates the pressure of solid waste environmental protection in the phosphorus chemical industry, and provides a new research idea for the harmless treatment of other toxic and harmful large-scale solid wastes, reducing the cost of solid waste treatment and simplifying the treatment process.

The long-term buffering effect of sense of coherence on psychopathological symptoms during the first year of the COVID-19 pandemic: A prospective observational study

The COVID-19 pandemic is a major chronic stressor affecting all societies and almost all individuals. Consequently, research demonstrated a negative impact of COVID-19 on mental health in parts of the general population. However, not all people are affected equally thus making the identification of resilience factors modulating the pandemic's impact on mental health an important research agenda. One of these factors is sense of coherence (SOC), the key component of the salutogenesis framework. The current study aimed at investigating the long-term relationship between SOC and psychopathological symptoms, and the impact of COVID-19-related rumination as its moderator. The prospective observational study assessed psychopathological symptoms and SOC before the COVID-19 outbreak in Germany (February 2020) and at six critical time points during the pandemic in an online panel (n = 1,479). Bivariate latent change score models and latent growth mixture modeling were used to analyze changes in psychopathological symptoms and SOC along with their interaction and to differentiate trajectories of COVID-19-related rumination. A model allowing for unidirectional coupling from SOC to psychopathological symptoms demonstrated best fit. In the total sample, psychopathological symptoms increased significantly over time. Previous SOC predicted later changes in psychopathological symptoms, whereby a stronger SOC was associated with a decrease in symptoms over time. The same pattern of results was evident in the high-rumination (17.2%) but not in the low-rumination group (82.8%). Our findings demonstrate that SOC is an important predictor and modulator of psychopathological symptoms during the COVID-19 pandemic, particularly in those respondents that ruminate about the pandemic.

Friend support buffers the relationship between maltreatment and nonsuicidal self-injury in adolescence.

Prior studies have mostly focused on the risk factors for nonsuicidal self-injury (NSSI), but only a few studies have emphasized the related protective factors. The present study examined whether maltreatment and behavioral problems were risk factors for NSSI. Moreover, we also sought to understand whether and how friend support provides a buffer against NSSI. A total of 436 adolescents completed self-report surveys that addressed maltreatment, behavioral problems, friend support, and NSSI at three different time points. There were significant positive correlations between maltreatment and NSSI. In the mediation analyses, we found that maltreatment was indirectly associated with NSSI via behavioral problems. Friend support demonstrated a long-term buffering effect on NSSI. Specifically, friend support had a protective effect on NSSI not only under high maltreatment levels, but also under high behavioral problem levels. These findings contribute to the understanding of the influences of both maltreatment, behavioral problems (risk factors), and friend support (protective factors) on NSSI. In the context of intervention and education, it is important to consider the value of friend support when discussing NSSI.

Phosphorus abundance and speciation in acid forest Podzols – Effect of postglacial weathering

The molecular speciation of phosphorus (P) in forest soils is of strategic importance for sustainable forest management. However, only limited information exists about soil P speciation in boreal forests. We combined P K-edge XANES spectroscopy, wet chemical P extractions, and X-ray diffraction analysis of soil minerals to investigate the vertical distribution of P species in seven podzolised forest soils differing in soil properties and climatic conditions. The results showed that the total P stock was on average, 4.0 g m−2 in the Oe horizon, 9.5 g m−2 in the A and E horizons, and substantially higher (117.5 g m−2, and 109.3 g m−2) in the B and C horizons down to 80 cm depth, respectively. Although the Oe horizons contain a minor total P stock, 87% of it was stored as organic P. The composition of P species in the P-depleted A/E horizons was highly variable depending on the site. However, of the P stored in B and C horizons down to 80 cm, 58% was adsorbed P, mostly to Al, while apatite accounted for 25% of P, most of which was found in the C horizons. The apatite stocks in the A/E, B, and C horizons (down to 80 cm) accounted for 2.5%, 20%, and 77.2%, respectively, of the total apatite for all the mineral soils studied. These figures can be explained, first, by the dissolution of primary mineral apatite caused mainly by acidification. Second, P uptake by plants and microorganisms, and the associated formation of the Oe horizons, led to the formation of soil organic P. Further, the formation of organo-metal complexes and podzolization led to the translocation of P to the B horizons, where P accumulated mostly as P adsorbed to imogolite-type materials (e.g. allophane) and ferrihydrite, as shown by P K-edge XANES spectroscopy. In conclusion, this study shows that despite the young age of these soils (<15,000 years), most of the primary mineral apatite in the upper 30 cm has been transformed into organic P, and Fe-, Al-bound PO4. Moreover, the subsoil P, mainly consisting of adsorbed P to Al, and apatite, dominates the P inventory and probably serves as a long-term buffer of P.

Long-term dispersion of river gravel in a canyon in the Atacama Desert, Central Andes, deduced from their 10Be concentrations

Intense storms or earthquakes in mountains can supply large amounts of gravel to rivers. Gravel clasts then travel at different rates, with periods of storage and periods of displacement leading to their downstream dispersion over millennia. The rate of this dispersion controls the long-term downcutting rate in mountainous rivers as well as the grain-size signature of climate and tectonic variations in sedimentary basins. Yet, the millennial dispersion rates of gravel are poorly known. Here, we use 10Be concentrations measured in individual pebbles from a localized source along a 56 km-long canyon in the Central Andes to document the distribution of long-term gravel transit rates. We show that an inverse grain-size velocity relationship previously established from short-term tracer gravel in different rivers worldwide can be extrapolated to the long-term transit rates in the Aroma River, suggesting some universality of this relationship. Gravel are also dispersed by large differences in the mean transport rates independent of gravel size, highlighting that some gravel rest at the river surface over tens of thousands of years. These different transport rates imply a strong spreading of the gravel plumes, providing direct proof for the long-term river buffering of sediment signals between mountainous sources and sedimentary basins. The inferred distribution of residence times suggests the first evidence of anomalous diffusion in gravel transport over long timespans.

Decreased buffering capacity and increased recovery time for legacy phosphorus in a typical watershed in eastern China between 1960 and 2010

Legacy phosphorus (P) accumulated in watersheds from excessive historical P inputs is recognized as an important component of water pollution control and sustainable P management in watersheds worldwide. However, little is known about how watershed P buffering capacity responds to legacy P pressures over time and how long it takes for riverine P concentrations to recover to a target level, especially in developing countries. This study examined long-term (1960–2010) accumulated legacy P stock, P buffering capacity and riverine TP flux dynamics to predict riverine P-reduction recovery times in the Yongan watershed of eastern China. Due to a growing legacy P stock coupled with changes in land use and climate, estimated short- and long-term buffering metrics (i.e., watershed ability to retain current year and historically accumulated surplus P, respectively) decreased by 65% and 36%, respectively, resulting in a 15-fold increase of riverine P flux between 1980 and 2010. An empirical model incorporating accumulated legacy P stock and annual precipitation was developed (R2 = 0.99) and used to estimate a critical legacy P stock of 22.2 ton P km−2 (95% CI 19.4–25.3 ton P km−2) that would prevent exceedance of a target riverine TP concentration of 0.05 mg P L−1. Using an exponential decay model, the recovery time for depleting the estimated legacy P stock in 2010 (29.3 ton P km−2) to the critical level (22.2 ton P km−2) via riverine flux was 456 years (95% CI 353–560 years), 159 years (95% CI 57–262 years) and 318 years (95% CI 238–400 years) under scenarios of a 4% reduction in annual P inputs, total cessation of P inputs, and 4% reduction of annual P inputs with a 10% increase in average annual precipitation, respectively. Given the lower P buffering capacity and lengthening recovery time, strategies to reduce P inputs and utilize soil legacy P for crop production are necessary to effectively control riverine P pollution and conserve global rock P resources. A long-term perspective that incorporates both contemporary and historical information is required for developing sustainable P management strategies to optimize both agronomic and environmental benefits at the watershed scale.

How service-users with intellectual disabilities understand challenging behaviour and approaches to managing it.

This study explored understandings that service-users with intellectual disabilities and challenging behaviour held around their behaviour, what shaped these understandings, and the relationship between how behaviours are managed and well-being. Eight participants (three female, five male) partook in individual semi-structured qualitative interviews. Interviews were transcribed and analysed using interpretative phenomenological analysis. Three master themes emerged from this analysis: (a) challenging behaviour can be explained via an internal or external frame of reference, with each framework having different implications for how participants attempted to manage behaviour. (b) Positive relationships provide a long-term buffer to challenging behaviour, with positive relationships with family, staff and peers operating through different mechanisms to achieve this. (c) A greater ability to exert power and control in day-to-day life was perceived to reduce challenging behaviour in the long term. Implications for practice are discussed.

Mathematical Model for Proactive Resequencing of Mixed Model Assembly Lines

Abstract Mixed model assembly lines are state of the art for automotive mass production. In the context of mass customization and indi-vidualization the car sequencing recently became more and more challenging due to varying assembly tasks and processing times. Classical principles such as the vehicle pearl chain are thus reaching their limits. Therefore, planned changes in the vehicle sequence during final assembly, Proactive Resequencing, was proposed to optimize utilization segment by segment. The concept leads to a long-term buffer planning problem on a strategic level as well as to an adapted vehicle sequencing problem with enhanced flexibility on an operative level. This paper introduces a mathematical model for the combined buffer planning and order sequencing problem for automotive assembly lines. It also outlines a solution approach for the mentioned production planning challenges separated by their timing preferences.

Hsp as a long-term buffer of the genome-wide mutation burden

Hsp as a long-term buffer of the genome-wide mutation burden

Watershed Buffering of Legacy Phosphorus Pressure at a Regional Scale: A Comparison Across Space and Time

Phosphorus (P) plays a crucial role in both agricultural production and water quality. There has been growing recognition of the importance of “legacy” P (surplus P that has accumulated in watersheds over time) for understanding contemporary water quality outcomes; however, little is known about how different watersheds respond to cumulative pressures from surplus P. The “buffering capacity” concept describes the ability of watersheds to attenuate P loading to surface waters by retaining P inputs over time. To explore the role of various watershed characteristics in buffering capacity, we used historic P data to calculate indices describing long- and short-term buffering for 16 large watersheds in southern Quebec, Canada, across a 30-year time span (1981–2011). We examined the correlation between these buffering capacity indicators and a set of key geochemical, hydrological, landscape and socio-ecological variables that we hypothesized could influence P buffering dynamics. Both short- and long-term buffering metrics were most strongly correlated with hydrological characteristics. Riverine TP flux across the watersheds was most strongly correlated with long-term buffering, which could represent a dominant influence of legacy P on contemporary riverine P flux. However, short- and long-term watershed buffering indices were not correlated with each other, suggesting distinctly different timescales and mechanisms of buffering. Combining estimates of long-term P accumulation along with biophysical characteristics of the watershed (including hydrology) explained a much greater share of the variation in riverine TP flux (R2 = 0.69) than biophysical characteristics alone (R2 = 0.36). Our findings reinforce the need to consider P buffering capacity and legacy P accumulation to help guide decision making around regional water quality targets across human-dominated landscapes.

Clarifying the concept of climate change refugia for coral reefs

Abstract Refugia can facilitate the persistence of biodiversity under changing environmental conditions, such as anthropogenic climate change, and therefore constitute the best chance of survival for many coral species in the wild. Despite an increasing amount of literature, the concept of coral reef refugia remains poorly defined; so that climate change refugia have been confused with other phenomena, including temporal refuges, pristine habitats and physiological processes such as adaptation and acclimatization. We propose six criteria that determine the capacity of refugia to facilitate species persistence, including long-term buffering, protection from multiple climatic stressors, accessibility, microclimatic heterogeneity, size, and low exposure to non-climate disturbances. Any effective, high-capacity coral reef refugium should be characterized by long-term buffering of environmental conditions (for several decades) and multi-stressor buffering (provision of suitable environmental conditions with respect to climatic change, particularly ocean warming and acidification). Although not always essential, the remaining criteria are important for quantifying the capacity of potential refugia.

Infiltration in layered loessial deposits: Revised numerical simulations and recharge assessment

Summary The objective of this study is to assess recharge rates and their timing under layered loessial deposits at the edge of arid zones. Particularly, this study is focused on the case of the coastal plain of Israel and Gaza. First, results of a large-scale field infiltration test were used to calibrate the van Genuchten parameters of hydraulic properties of the loessial sediments using HYDRUS (2D/3D). Second, optimized soil hydraulic parameters were used by HYDRUS-1D to simulate the water balance of the sandy-loess sediments during a 25-year period (1990–2015) for three environmental conditions: bare soil, and soil with both sparse and dense natural vegetation. The best inverse parameter optimization run fitted the infiltration test data with the RMSE of 0.27 d (with respect to a moisture front arrival) and R 2 of 96%. The calibrated model indicates that hydraulic conductivities of the two soil horizons, namely sandy loam and sandy clay loam, are 81 cm/d and 17.5 cm/d, respectively. These values are significantly lower than those previously reported, based on numerical simulations, for the same site. HYDRUS-1D simulation of natural recharge under bare soil resulted in recharge estimates (to the aquifer) in the range of 21–93 mm/yr, with an average recharge of 63 mm/yr. Annual precipitation in the same period varied between 100 and 300 mm/yr, with an average of 185 mm/yr. For semi-stabilized dunes, with 26% of the soil surface covered by local shrub ( Artemisia monosperma ), the mean annual recharge was 28 mm. For the stabilized landscape, with as much as 50% vegetation coverage, it was only 2–3 mm/yr. In other words, loessial sediments can either be a source of significant recharge, or of no recharge at all, depending on the degree of vegetative cover. Additionally, the time lag between specific rainy seasons and corresponding recharge events at a depth of 22 m, increased from 2.5 to 5 years, and to about 20 years, respectively, with an increasing vegetative cover. For this reason, and also likely due to a great depth of loessial sediments, no correlation was found between annual recharge and annual precipitations of the same year or subsequent years. Similarly, no differences were found between summer and winter recharge fluxes. Instead, numerical simulations indicated continuous year-round recharge of the aquifer. We conclude that the layered subsurface acts as a short-term (annual) and long-term (multi-annual) buffer to smooth sudden precipitation/infiltration events. Vegetation conditions can help in predicting long-term recharge rates (as percentage of annual precipitation), which in turn need to be considered when assigning recharge characteristics in regional assessments and models.

Harvest-induced evolution and effective population size.

Much has been written about fishery‐induced evolution (FIE) in exploited species, but relatively little attention has been paid to the consequences for one of the most important parameters in evolutionary biology—effective population size (N e). We use a combination of simulations of Atlantic cod populations experiencing harvest, artificial manipulation of cod life tables, and analytical methods to explore how adding harvest to natural mortality affects N e, census size (N), and the ratio N e/N. We show that harvest‐mediated reductions in N e are due entirely to reductions in recruitment, because increasing adult mortality actually increases the N e/N ratio. This means that proportional reductions in abundance caused by harvest represent an upper limit to the proportional reductions in N e, and that in some cases N e can even increase with increased harvest. This result is a quite general consequence of increased adult mortality and does not depend on harvest selectivity or FIE, although both of these influence the results in a quantitative way. In scenarios that allowed evolution, N e recovered quickly after harvest ended and remained higher than in the preharvest population for well over a century, which indicates that evolution can help provide a long‐term buffer against loss of genetic variability.

A Cross-Layer Perspective on Energy-Harvesting-Aided Green Communications Over Fading Channels

In this paper, we consider the power allocation of the physical layer and the buffer delay of the upper application layer in energy harvesting green networks. The total power required for reliable transmission includes the transmission power and the circuit power. The harvested power (which is stored in a battery) and the grid power constitute the power resource. The uncertainty of data generated from the upper layer, the intermittence of the harvested energy, and the variation of the fading channel are taken into account and described as independent Markov processes. In each transmission, the transmitter decides the transmission rate and the allocated power from the battery, and the rest of the required power will be supplied by the power grid. The objective is to find an allocation sequence of transmission rate and battery power to minimize the long-term average buffer delay under the average grid power constraint. A stochastic optimization problem is formulated accordingly to find such transmission rate and battery power sequence. Furthermore, the optimization problem is reformulated as a constrained Markov decision process (MDP) problem whose policy is a 2-D vector with the transmission rate and the power allocation of the battery as its elements. We prove that the optimal policy of the constrained MDP can be obtained by solving the unconstrained MDP. Then, we focus on the analysis of the unconstrained average-cost MDP. The structural properties of the average optimal policy are derived. Moreover, we discuss the relations between elements of the 2-D policy. Next, based on the theoretical analysis, the algorithm to find the constrained optimal policy is presented for the finite-state-space scenario. In addition, heuristic policies (two deterministic policies and a mixed policy) with low complexity are given for the general state space. Finally, simulations are performed under these policies to demonstrate their effectiveness.

Use of silicate minerals for long-term pH control during reductive dechlorination of high tetrachloroethene concentrations in continuous flow-through columns

The long-term buffering potential of three silicate minerals (diopside, fayalite and forsterite) present as fine particles in porous quartz sand medium was evaluated in flow-through column experiments over a period of 6.5months. The columns were operated with PCE concentrations close to saturation and inoculated with the organohalide-respiring consortium SDC-9™, which is able to completely dechlorinate PCE to ethene at high concentrations. In the absence of pH buffering agents, fermentation and organohalide respiration drove the pH close to 6.1, leading to severe inhibition of PCE dechlorination. Forsterite and fayalite were able to maintain the pH close to 7.5 and 6.5, respectively, and to sustain the production of VC and ethene. Diopside gradually lost its buffering capacity during the first 84days due to the formation of a low reactive leached layer but dechlorination to cis-DCE was still achieved. Among the three minerals tested, forsterite was identified as the best buffering agent. Its presence led to the best PCE removal performance and the highest relative abundance of Dehalococcoides. This study showed that forsterite and fayalite are promising sources of long-term pH buffering for in situ bioremediation of source-zone PCE.

Antimicrobial activities of green tea extract on the retardation of kimchi fermentation

Kimchi fermentation is complex process which really depends on the composition of microfloa under the optimum ripening environment such as salt concentration, acidity, pH and temperature conditions. Most kinds of bacteria belonging to Lactobacillus group have been identified in kimchi, which continuously produce lactic acids after ripening and cause the change of kimchi tasty and physical texture. Green tea extract as a natural preservative was investigated on the antimicrobial activity and the change of pH, in terms of retardation of kimch fermentation. Minimal Inhibitory Concentration (MIC), paper disc assay, bacterial growth, and pH change were tested against four microorgasnisms, Leuconostoc mesenteroides, Lactobacillussake, Lactobacillus plantarum, and Weissellakoreensis. 2 mg/mL of green tea extract completely inhibited the growth of test organisms after 5–7 hours. Furthermore, it showed the maximized clear zone (24–34 mm) was observed at the 2mg/disc concentration. pH change resulted in a slow downward drift for fermentation period. Moreover, green tea extract showed long-term buffer effects for over 35 days (5 weeks) at 4°C.

Molecular transformation and degradation of refractory dissolved organic matter in the Atlantic and Southern Ocean

More than 90% of the global ocean dissolved organic carbon (DOC) is refractory, has an average age of 4000–6000years and a lifespan from months to millennia. The fraction of dissolved organic matter (DOM) that is resistant to degradation is a long-term buffer in the global carbon cycle but its chemical composition, structure, and biochemical formation and degradation mechanisms are still unresolved. We have compiled the most comprehensive molecular dataset of 197 Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) analyses from solid-phase extracted marine DOM covering two major oceans, the Atlantic sector of the Southern Ocean and the East Atlantic Ocean (ranging from 50°N to 70°S). Molecular trends and radiocarbon dating of 34 DOM samples (comprising Δ14C values from −229‰ to −495‰) were combined to model an integrated degradation rate for bulk DOC resulting in a predicted age of >24ka for the most persistent DOM fraction. First order kinetic degradation rates for 1557 mass peaks indicate that numerous DOM molecules cycle on timescales much longer than the turnover of the bulk DOC pool (estimated residence times of up to ~100ka) and the range of validity of radiocarbon dating. Changes in elemental composition were determined by assigning molecular formulae to the detected mass peaks. The combination of residence times with molecular information enabled modelling of the average elemental composition of the slowest degrading fraction of the DOM pool. In our dataset, a group of 361 molecular formulae represented the most stable composition in the oceanic environment (“island of stability”). These most persistent compounds encompass only a narrow range of the molecular elemental ratios H/C (average of 1.17±0.13), and O/C (average of 0.52±0.10) and molecular masses (360±28 and 497±51Da). In the Weddell Sea DOC concentrations in the surface waters were low (46.3±3.3μM) while the organic radiocarbon was significantly more depleted than that of the East Atlantic, representing average surface water DOM ages of 4920±180a. These results are in accordance with a highly degraded DOM in the Weddell Sea surface water as also shown by the molecular degradation index IDEG obtained from FT-ICR MS data. Further, we identified 339 molecular formulae which probably contribute to an increased DOC concentration in the Southern Ocean and potentially reflect an accumulation or enhanced sequestration of refractory DOC in the Weddell Sea. These results will contribute to a better understanding of the persistent nature of marine DOM and its role as an oceanic carbon buffer in a changing climate.

The Immediate and Delayed Cardiovascular Benefits of Forgiving

The putative health benefits of forgiveness may include long-term buffering against cardiovascular reactivity associated with rumination. Although studies show short-term benefits of adopting a forgiving perspective, it is uncertain whether this perspective protects against repeated future rumination on offenses, which may be necessary for long-term health benefits. Also unclear is whether forgiveness offers unique benefits beyond simple distraction. Cardiovascular parameters (systolic blood pressure [SBP], diastolic blood pressure [DBP], and heart rate) were measured while 202 participants thought about a previous offense from an angry or forgiving perspective or were distracted. All participants were then distracted for 5 minutes, after which they freely ruminated on the offense. Angry rumination initially yielded the greatest increase in blood pressure from baseline (mean [M] [standard deviation {SD}]: SBP = 9.24 [11.16]; M [SD]: DBP = 4.69 [7.48]) compared with forgiveness (M [SD]: SBP = 3.30 [6.48]; M [SD]: DBP = 1.51 [4.94]) and distraction (M [SD]: SBP = 4.81 [6.28]; M [SD]: DBP = 1.75 [3.80]), which did not differ from each other (p > .30). During free rumination, however, those who had previously focused on forgiveness showed less reactivity (M [SD]: SBP = 7.33 [9.61]; M [SD]: DBP = 4.73 [7.33]) than those who had been distracted (M [SD]: SBP = 10.50 [7.77]; M [SD]: DBP = 7.71 [6.83]) and those who previously focused on angry rumination (M [SD]: SBP = 12.04 [11.74]; M [SD]: DBP = 8.64 [12.63]). There were no differences for heart rate. Forgiveness seems to lower reactivity both during the initial cognitive process and, more importantly, during mental recreations of an offense soon thereafter, potentially offering sustained protection, whereas effects of distraction appear transient.