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Abstract Understanding the long‐term effects of population and GDP changes requires a multisectoral and regional understanding of the coupled human‐Earth system, as the long‐term evolution of this coupled system is influenced by human decisions and the Earth system. This study investigates the impact of compounding economic and population growth uncertainties on long‐term multisectoral outcomes. We use the Global Change Analysis Model (GCAM) to explore the influence of compounding and feedback between future GDP and population growth on four key sectors: final energy consumption, water withdrawal, staple food prices, and CO2 emissions. The results show that uncertainties in GDP and population compound, resulting in a magnification of tail risks for outcomes across sectors and regions. Compounding uncertainties significantly impact metrics such as CO2 emissions and final energy consumption, particularly at the upper tail at both global and regional levels. However, the impact of staple food prices and water withdrawal depends on regional factors. Additionally, an alternative low‐carbon transition scenario could compound uncertainties and increase tail risk, particularly in staple food prices, highlighting the influence of emergent constraints on land availability and food‐energy competition for land use. The findings underscore the importance of considering and adequately accounting for compounding uncertainties in key drivers of multisectoral systems to enhance our comprehensive understanding of the complex nature of multisectoral systems. The paper provides valuable insights into the potential implications of compounding uncertainties.

Abstract Future water scarcity is a global concern with impacts across the energy, water, and land (EWL) sectors. Countries in Latin America and the Caribbean (LAC) are significant producers of agricultural goods, so disruptions resulting from water scarcity in LAC have global importance. Understanding where water scarcity in LAC could occur and what could exacerbate it is critical for strategic resource management and planning, both regionally and globally. Assessing future water scarcity in LAC is challenging given the complex interactions among the EWL sectors and the multiple uncertainties acting across spatial scales. To illuminate these dynamics, we use scenario discovery on a large ensemble representing diverse futures simulated using an integrated human‐environmental systems model. We quantify future water scarcity and its economic impacts across several physical and economic metrics. We find that future levels of reservoir storage expansion could be a significant driver of physical and economic water scarcity, highlighting the importance of strategic water infrastructure development in maintaining future water availability. Changes in crop profit are driven by both water supply and demand, emphasizing the complexity of EWL multisector dynamics. While most of LAC is poised to have abundant land and water resources available for future development, basins in Mexico and along the Pacific coast of South America experience high exposure to severe outcomes and uncertainty across outcomes for at least one metric. We find that drivers of severe scarcity vary spatially and across metrics, highlighting the region's heterogeneity and the importance of considering multiple metrics to assess water scarcity.

Abstract Land scarcity is increasing over time, driven by complex multisector dynamics. The impacts of land scarcity on the economy and environment are multi‐faceted and regional, so any action to convert land will contain inherent tradeoffs. These impacts are complicated by the deeply uncertain evolution of the various sectors influencing land scarcity. A need therefore exists to provide multi‐metric and multi‐sector assessments that are robust to myriad uncertainties. Land conservation effectively limits the supply of productive land, while biofuel consumption increases the demand and competition for that land, and how these dynamics individually and jointly propagate to economic and environmental impacts is an important open question. To address this, we adopt the Global Change Analysis Model (GCAM) that has representations of various important systems including the climate, macroeconomic, energy, agriculture and land, and water resources systems. Various scenarios of increased land demand (from biofuels) and decreased land supply (from conservation) under various socioeconomic scenarios drawn from the SSPs were simulated using GCAM. We find that while biofuel consumption and land conservation reduce carbon emissions, this comes at the cost of higher food prices, reduced crop production, and increased water withdrawals. Additionally, some regions experience these tradeoffs more severely than others and are more heavily impacted from the same biofuel mandate or by an additional percent of protected land. These and other findings highlight the importance of multisector modeling frameworks that capture many cross‐sector linkages, and acknowledge the important uncertainties confronting the human‐Earth system when making any analysis of land scarcity impacts.

Background: Cardiac resynchronization therapy (CRT) improves morbidity and mortality in patients with heart failure. Although structural remodelling correlates with improved long-term outcomes, the role of electrical remodelling is poorly understood. This study aimed to evaluate electrical remodelling following CRT using a quadripolar left ventricular (LV) lead and to correlate this with structural remodelling., Methods: Consecutive patients undergoing initial CRT implantation using a quadripolar LV lead were enrolled. Patients were followed up for 12 months. Twelve lead ECG, transthoracic echocardiogram, and evaluation of intracardiac electrograms (EGM) were performed. Measures included right and left ventricular lead intrinsic delay, RV-pacing to LV-sensing (RVp-LVs) delay, and LV-pacing to RV-sensing (LVp-RVs) delay. The electrical changes were then correlated with echocardiographic response to CRT, defined by ≥15% relative reduction in LVESV and ≥ 5% absolute improvement in EF on TTE. Activation sequence was determined using the quadripolar lead., Results: Forty patients were enrolled. Mean intrinsic RV-LV EGM values decreased from 121.9 ± 14.7 ms to 109.1 ± 15.0 ms ( P < .01), mean RVp-LVs EGM values from 146.7 ± 16.7 ms to 135.1 ± 13.1 ms, ( P < .01), and mean LVp-RVs EGM values from 155.7 ± 18.1 ms to 144.2 ± 17.1 ms ( P < .01). The improvement in intrinsic RV-LV EGM was 14.9 ± 8.5 ms in responders vs 8.9 ± 7.9 ms in nonresponders to CRT ( P < .05). Changes in activation sequence did not correlate with CRT response., Conclusions: This novel study used EGMs from a quadripolar LV lead to demonstrate electrical remodelling occurs following CRT. A nonsignificant trend suggests that electrical remodelling in CRT is greater in responders compared to nonresponders, although further study is needed.

The hydrocarbons preserved in an Archean rock were extracted, and their composition and distribution in consecutive slices from the outside to the inside of the rock were examined. The 2.7 Ga rock was collected from the Fortescue Group in the Pilbara region, Western Australia. The bitumen I (solvent-extracted rock) and bitumen II (solvent-extracted hydrochloric acid-treated rock) fractions have different hydrocarbon compositions. Bitumen I contains only trace amounts of aliphatic hydrocarbons and virtually no aromatic hydrocarbons. In contrast, bitumen II contains abundant aliphatic and aromatic hydrocarbons. The difference seems to reflect the weathering history and preservational environment of the investigated rock. Aliphatic hydrocarbons in bitumen I are considered to be mainly from later hydrocarbon inputs, after initial deposition and burial, and are therefore not indigenous. The lack of aromatic hydrocarbons in bitumen I suggests a severe weathering environment since uplift and exposure of the rock at the Earth's surface in the Cenozoic. On the other hand, the high abundance of aromatic hydrocarbons in bitumen II suggests that bitumen II hydrocarbons have been physically isolated from removal by their encapsulation within carbonate minerals. The richness of aromatic hydrocarbons and the relative scarcity of aliphatic hydrocarbons may reflect the original compositions of organic materials biosynthesised in ancient organisms in the Archean era, or the high thermal maturity of the rock. Cyanobacterial biomarkers were observed in the surficial slices of the rock, which may indicate that endolithic cyanobacteria inhabited the surface outcrop. The distribution of aliphatic and aromatic hydrocarbons implies a high thermal maturity, which is consistent with the lack of any specific biomarkers, such as hopanes and steranes, and the prehnite-pumpellyite facies metamorphic grade., (© 2014 John Wiley & Sons Ltd.)

In a retrospective survey, the incidence of neural tube defects in liveborn trimsomy 18 was found to be 6.2 per cent. Based on these data one would expect to find trisomy 18 in 1 of the 117 patients with myeloidysplasia; the incidence of trisomy 18 in dysraphic fetuses would be anticipated to be higher. These observations underscore the need for amniocentesis karyotyping of fetuses with neural tube defects, and the importance of careful examination of infants born with neural tube defects.