Hydrologic change in New Zealand during the last deglaciation linked to reorganization of the Southern Hemisphere westerly winds

Millennial‐scale climate anomalies punctuating the last deglaciation were expressed differently in the Northern and Southern Hemispheres. While changes in oceanic meridional overturning circulation have been invoked to explain these disparities, the nearly synchronous onset of such events requires atmospheric mediation. Yet the extent and structure of atmospheric reorganization on millennial timescales remains unclear. In particular, the role of the Southern Hemisphere westerly winds (SHWW) and associated storm tracks is poorly constrained, largely due to the paucity of accessible archives of wind behavior. Here we present a new paleohydrologic record from a Lake Hayes, New Zealand (45° S) sediment core from ~17‐9 ka. Using two independent proxies for lake hydrology (Ca/Ti in sediments and δD values of aquatic plant biomarkers), we find evidence for a wetter Antarctic Cold Reversal (ACR, 14.7‐13.0 ka) and a drying trend during the Younger Dryas (YD, 12.9‐11.6 ka) and early Holocene (11.7 ka onward in this record). Comparisons of the Lake Hayes record with other Southern Hemisphere sites indicate coherent atmospheric shifts during the ACR and YD, whereby the former is wetter/cooler and the latter is drier/warmer. The wet/cool phase is associated with a northward shift and/or strengthening of the SHWW, whereas the drier/warmer phase indicates weaker mid‐latitude winds. These climatic trends are opposite to the Northern Hemisphere. There is a decoupling of climatic trends between Southern Hemisphere low‐ and mid‐latitude climates in the early Holocene, which could be explained by several mechanisms, such as the retreat of Antarctic sea ice

Beliefs and Attitude Changes Towards Virtual Reality Usefulness After Disabilities Simulation

ABSTRACT Virtual Reality (VR) has been utilized often as a potential recreational tool for enjoyment by generating false realities to interact with, but in regards to a potential tool to introduce understanding in cultures and empathetic responses it has seen little use. Stereotypical beliefs seem to exist that disabled people are unable to care for themselves (Burgstahler & Doe, 2004). Furthermore, individuals without disabilities may not fully understand how a person with disabilities is able to even function in daily life (McKenny, 2018). Leo and Goodwin (2016) emphasized the value of simulation exercises to change individual attitudes and perspectives towards those who live with disabilities. PURPOSE: The purpose of the study was to assess people’s attitudes and belief changes towards the use of VR after participating in disability simulations. METHODS: Implemented in a class about motor movement in special populations, subjects were college students(n=44) who were administered a Likert scale pre-survey. The survey emphasized subject’s beliefs around the use of VR for gaming, education, work preparation, therapy, use for individuals with disabilities, and those developing empathy towards individuals with disabilities. Subjects then participated in a VR training session, an autism emotional disturbance simulation, and a simulation of what a blind person’s imagination goes through while handling sounds and touch sensations around them. A Wilcoxon Signed Rank Test was used in SPSS software to analyze the nonparametric data for two nominal variables comparing pre and post beliefs and attitudes. RESULTS: Overall, most questions posed to the subjects were not found to be statistically significant with the error rate used throughout the entirety of the study (α = 0.05). However, when asked about the ability for VR simulations to create or increase empathy in the subjects towards those with disabilities there was a statistical significance (Z = -2.02, p = 0.042.) Additionally, positive trends were found in the aggregated mean scores when comparing the pre and post surveys with subjects across all variables in the survey. CONCLUSION: While more categories were expected to have a significant change, only empathy showed statistical significant. This result encourages the ability of VR simulations to assist in understanding and sharing comprehension with another individual who has disabilities or in a restricted perceptual motor/behavioral state. Further research on the topic may also reveal that the positive trends found in this study may have statistical significance if used in larger sample sizes

Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

Palynofacies assemblages reflect sources of organic matter in New Zealand fjords

Understanding sources and transport pathways of organic carbon in fjord systems is important to quantify carbon cycling in coastal settings. Provenance of surficial sediment organic carbon in Fiordland National Park (southwestern New Zealand) has previously been estimated using a range of techniques, including mixing models derived from stable isotopes and lipid biomarker distributions. Here, we present the first application of palynofacies to explore the sources of particulate organic carbon to five fjords along the SW margin of New Zealand, to further discriminate the provenance of organic carbon in the fjords. We find good correlation between isotopic-and biomarker-derived proxies for organic carbon provenance and our new palynofacies observations. We observe strong down-fjord gradients of decreasing terrestrially derived organic carbon further from the river inflow at fjord heads. Fjords with small catchments and minor fresh water inflow exhibit reversed gradients, indicating that volume of freshwater entering at the fjord head is a primary mechanism to transport particulates down fjord rather than local transport from fjord sides. The palynofacies data also confirmed previously recorded latitudinal trends (i.e. between fjords), of less frequent and more weathered terrestrially derived organic carbon in the southern fjords, consistent with enhanced marine inflow and longer transport times in the southern catchments. Dinocyst assemblages also exhibit a strong latitudinal gradient, with assemblages dominated by heterotrophic forms in the north. In addition to providing support for previous studies, this approach allows finer discrimination of terrestrial organic carbon than previously, for example variation of leaf material. This study demonstrates that visual palynofacies analysis is a valuable tool to pinpoint origins of organic carbon in fjord systems, providing different but complementary information to other proxies

Palynofacies assemblages reflect sources of organic matter in New Zealand fjords

Understanding sources and transport pathways of organic carbon in fjord systems is important to quantify carbon cycling in coastal settings. Provenance of surficial sediment organic carbon in Fiordland National Park (southwestern New Zealand) has previously been estimated using a range of techniques, including mixing models derived from stable isotopes and lipid biomarker distributions. Here, we present the first application of palynofacies to explore the sources of particulate organic carbon to five fjords along the SW margin of New Zealand, to further discriminate the provenance of organic carbon in the fjords. We find good correlation between isotopic-and biomarker-derived proxies for organic carbon provenance and our new palynofacies observations. We observe strong down-fjord gradients of decreasing terrestrially derived organic carbon further from the river inflow at fjord heads. Fjords with small catchments and minor fresh water inflow exhibit reversed gradients, indicating that volume of freshwater entering at the fjord head is a primary mechanism to transport particulates down fjord rather than local transport from fjord sides. The palynofacies data also confirmed previously recorded latitudinal trends (i.e. between fjords), of less frequent and more weathered terrestrially derived organic carbon in the southern fjords, consistent with enhanced marine inflow and longer transport times in the southern catchments. Dinocyst assemblages also exhibit a strong latitudinal gradient, with assemblages dominated by heterotrophic forms in the north. In addition to providing support for previous studies, this approach allows finer discrimination of terrestrial organic carbon than previously, for example variation of leaf material. This study demonstrates that visual palynofacies analysis is a valuable tool to pinpoint origins of organic carbon in fjord systems, providing different but complementary information to other proxies

A New Zealand perspective on centennial-scale Southern Hemisphere westerly wind shifts during the last two millennia

The strength and latitudinal position of the Southern Hemisphere westerly winds control regional climate and influence the global carbon cycle by physically regulating Southern Ocean CO_2 exchange with the atmosphere. However, the mechanisms driving interannual to millennial variability of the westerlies remain poorly understood. Here, we present an 1800-yr record of westerly wind variability recorded in New Zealand fjord sediments. Located west of the Southern Alps, fjord basins receive large amounts of westerly-driven orographic precipitation (>6 m yr^(−1)) and strong winds lead to vigorous fjord mixing. Because of these links, reconstructing precipitation and fjord circulation provides information on westerly wind behavior over southwest New Zealand. Applying a multiproxy approach, we find several intervals of inferred regional wind variability. The intervals of 1450-1400, 825-775, 575-550, and 50-0 cal yr BP were anomalously wet, while 325-300 and 250-225 cal yr BP were anomalously dry. These interpreted intervals appear to be in phase with regional paleoclimate records. Two centennial-scale wet intervals align with a multi-centennial warm interval identified in the Pages2k Australasian temperature reconstruction, while the drier intervals generally occur during cooler times. The wet/dry intervals presented here are matched by opposite wind and/or precipitation trends reconstructed from the windfield core in Chile and the southern windfield margin in Antarctica. Such spatial patterns support the notion of centennial-scale latitudinal wind shifts or contraction/expansion of the core. Consistent with observations, all sites show wind strengthening from ∼50 cal yr BP to present, indicating an overall intensification of winds that is observed in modern instrumental and reanalysis data sets

Trace metal cycling and ^(238)U/^(235)U in New Zealand’s fjords: Implications for reconstructing global paleoredox conditions in organic-rich sediments

Reconstructing the history of ocean oxygenation provides insight into links between ocean anoxia, biogeochemical cycles, and climate. Certain redox-sensitive elements respond to changes in marine oxygen content through phase shifts and concomitant isotopic fractionation, providing new diagnostic proxies of past ocean hypoxia. Here we explore the behavior and inter-dependence of a suite of commonly utilized redox-sensitive trace metals (U, Mo, Fe, and Mn) and the emerging “stable” isotope system of U (^(238)U/^(235)U, or δ^(238)U) in New Zealand fjords. These semi-restricted basins have chemical conditions spanning the complete redox spectrum from fully oxygenated to suboxic to intermittently anoxic/euxinic. In the anoxic water column, U and Mo concentrations decrease, while Fe and Mn concentrations increase. Similarly, signals of past euxinic conditions can be found by U, Mo, Fe, and Mn enrichment in the underlying sediments. The expected U isotopic shift toward a lower δ^(238)U in the anoxic water column due to U(VI)–U(IV) reduction is not observed; instead, water column δ^(238)U profiles are consistent in fjords of all oxygen content, falling within previously reported ranges for open ocean seawater (δ^(238)U = −0.42 ± 0.07‰). Additionally, surface sediment δ^(238)U results show evidence for competing U isotope fractionation processes. One site indicates increased export of ^(238)U from seawater to the underlying sediments (fractionation between aqueous seawater U and particulate sediment U, or Δ_(U(aq)−U(solid)) = −0.25‰), consistent with redox-driven fractionation. Another site suggests potential U(VI) adsorption-driven fractionation, reflecting increased export of ^(235)U from seawater to sediments (Δ_(U(aq)−U(solid)) = 0.25‰). We discuss several potential factors that could alter δ^(238)U in waters and sediments beyond redox-driven shifts, including adsorption to organic matter in waters of high primary productivity, reaction rates for competing processes of U adsorption and release, and isotopic constraints of U coming into the system from terrestrial environments. These potential complications should be understood and constrained through observations, experiments, and models before future application of δ^(238)U as a global paleoredox tracer can achieve its full potential