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Michael Weekes

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Nick K. Jones1,2*, Lucy Rivett1,2*, Chris Workman3, Mark Ferris3, Ashley Shaw1, Cambridge COVID-19 Collaboration1,4, Paul J. Lehner1,4, Rob Howes5, Giles Wright3, Nicholas J. Matheson1,4,6¶, Michael P. Weekes1,7¶1 Cambridge University NHS Hospitals Foundation Trust, Cambridge, UK2 Clinical Microbiology & Public Health Laboratory, Public Health England, Cambridge, UK3 Occupational Health and Wellbeing, Cambridge Biomedical Campus, Cambridge, UK4 Cambridge Institute of Therapeutic Immunology & Infectious Disease, University of Cambridge, Cambridge, UK5 Cambridge COVID-19 Testing Centre and AstraZeneca, Anne Mclaren Building, Cambridge, UK6 NHS Blood and Transplant, Cambridge, UK7 Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK*Joint first authorship¶Joint last authorshipCorrespondence: mpw1001@cam.ac.ukThe UK has initiated mass COVID-19 immunisation, with healthcare workers (HCWs) given early priority because of the potential for workplace exposure and risk of onward transmission to patients. The UK’s Joint Committee on Vaccination and Immunisation has recommended maximising the number of people vaccinated with first doses at the expense of early booster vaccinations, based on single dose efficacy against symptomatic COVID-19 disease.1-3At the time of writing, three COVID-19 vaccines have been granted emergency use authorisation in the UK, including the BNT162b2 mRNA COVID-19 vaccine (Pfizer-BioNTech). A vital outstanding question is whether this vaccine prevents or promotes asymptomatic SARS-CoV-2 infection, rather than symptomatic COVID-19 disease, because sub-clinical infection following vaccination could continue to drive transmission. This is especially important because many UK HCWs have received this vaccine, and nosocomial COVID-19 infection has been a persistent problem.Through the implementation of a 24 h-turnaround PCR-based comprehensive HCW screening programme at Cambridge University Hospitals NHS Foundation Trust (CUHNFT), we previously demonstrated the frequent presence of pauci- and asymptomatic infection amongst HCWs during the UK’s first wave of the COVID-19 pandemic.4 Here, we evaluate the effect of first-dose BNT162b2 vaccination on test positivity rates and cycle threshold (Ct) values in the asymptomatic arm of our programme, which now offers weekly screening to all staff.Vaccination of HCWs at CUHNFT began on 8th December 2020, with mass vaccination from 8th January 2021. Here, we analyse data from the two weeks spanning 18thto 31st January 2021, during which: (a) the prevalence of COVID-19 amongst HCWs remained approximately constant; and (b) we screened comparable numbers of vaccinated and unvaccinated HCWs. Over this period, 4,408 (week 1) and 4,411 (week 2) PCR tests were performed from individuals reporting well to work. We stratified HCWs <12 days or > 12 days post-vaccination because this was the point at which protection against symptomatic infection began to appear in phase III clinical trial.226/3,252 (0·80%) tests from unvaccinated HCWs were positive (Ct<36), compared to 13/3,535 (0·37%) from HCWs <12 days post-vaccination and 4/1,989 (0·20%) tests from HCWs ≥12 days post-vaccination (p=0·023 and p=0·004, respectively; Fisher’s exact test, Figure). This suggests a four-fold decrease in the risk of asymptomatic SARS-CoV-2 infection amongst HCWs ≥12 days post-vaccination, compared to unvaccinated HCWs, with an intermediate effect amongst HCWs <12 days post-vaccination.A marked reduction in infections was also seen when analyses were repeated with: (a) inclusion of HCWs testing positive through both the symptomatic and asymptomatic arms of the programme (56/3,282 (1·71%) unvaccinated vs 8/1,997 (0·40%) ≥12 days post-vaccination, 4·3-fold reduction, p=0·00001); (b) inclusion of PCR tests which were positive at the limit of detection (Ct>36, 42/3,268 (1·29%) vs 15/2,000 (0·75%), 1·7-fold reduction, p=0·075); and (c) extension of the period of analysis to include six weeks from December 28th to February 7th 2021 (113/14,083 (0·80%) vs 5/4,872 (0·10%), 7·8-fold reduction, p=1x10-9). In addition, the median Ct value of positive tests showed a non-significant trend towards increase between unvaccinated HCWs and HCWs > 12 days post-vaccination (23·3 to 30·3, Figure), suggesting that samples from vaccinated individuals had lower viral loads.We therefore provide real-world evidence for a high level of protection against asymptomatic SARS-CoV-2 infection after a single dose of BNT162b2 vaccine, at a time of predominant transmission of the UK COVID-19 variant of concern 202012/01 (lineage B.1.1.7), and amongst a population with a relatively low frequency of prior infection (7.2% antibody positive).5This work was funded by a Wellcome Senior Clinical Research Fellowship to MPW (108070/Z/15/Z), a Wellcome Principal Research Fellowship to PJL (210688/Z/18/Z), and an MRC Clinician Scientist Fellowship (MR/P008801/1) and NHSBT workpackage (WPA15-02) to NJM. Funding was also received from Addenbrooke’s Charitable Trust and the Cambridge Biomedical Research Centre. We also acknowledge contributions from all staff at CUHNFT Occupational Health and Wellbeing and the Cambridge COVID-19 Testing Centre.

Guangming Wang

and 4 more

Tam Hunt

and 1 more

Tam Hunt [1], Jonathan SchoolerUniversity of California Santa Barbara Synchronization, harmonization, vibrations, or simply resonance in its most general sense seems to have an integral relationship with consciousness itself. One of the possible “neural correlates of consciousness” in mammalian brains is a combination of gamma, beta and theta synchrony. More broadly, we see similar kinds of resonance patterns in living and non-living structures of many types. What clues can resonance provide about the nature of consciousness more generally? This paper provides an overview of resonating structures in the fields of neuroscience, biology and physics and attempts to coalesce these data into a solution to what we see as the “easy part” of the Hard Problem, which is generally known as the “combination problem” or the “binding problem.” The combination problem asks: how do micro-conscious entities combine into a higher-level macro-consciousness? The proposed solution in the context of mammalian consciousness suggests that a shared resonance is what allows different parts of the brain to achieve a phase transition in the speed and bandwidth of information flows between the constituent parts. This phase transition allows for richer varieties of consciousness to arise, with the character and content of that consciousness in each moment determined by the particular set of constituent neurons. We also offer more general insights into the ontology of consciousness and suggest that consciousness manifests as a relatively smooth continuum of increasing richness in all physical processes, distinguishing our view from emergentist materialism. We refer to this approach as a (general) resonance theory of consciousness and offer some responses to Chalmers’ questions about the different kinds of “combination problem.”  At the heart of the universe is a steady, insistent beat: the sound of cycles in sync…. [T]hese feats of synchrony occur spontaneously, almost as if nature has an eerie yearning for order. Steven Strogatz, Sync: How Order Emerges From Chaos in the Universe, Nature and Daily Life (2003) If you want to find the secrets of the universe, think in terms of energy, frequency and vibration.Nikola Tesla (1942) I.               Introduction Is there an “easy part” and a “hard part” to the Hard Problem of consciousness? In this paper, we suggest that there is. The harder part is arriving at a philosophical position with respect to the relationship of matter and mind. This paper is about the “easy part” of the Hard Problem but we address the “hard part” briefly in this introduction.  We have both arrived, after much deliberation, at the position of panpsychism or panexperientialism (all matter has at least some associated mind/experience and vice versa). This is the view that all things and processes have both mental and physical aspects. Matter and mind are two sides of the same coin.  Panpsychism is one of many possible approaches that addresses the “hard part” of the Hard Problem. We adopt this position for all the reasons various authors have listed (Chalmers 1996, Griffin 1997, Hunt 2011, Goff 2017). This first step is particularly powerful if we adopt the Whiteheadian version of panpsychism (Whitehead 1929).  Reaching a position on this fundamental question of how mind relates to matter must be based on a “weight of plausibility” approach, rather than on definitive evidence, because establishing definitive evidence with respect to the presence of mind/experience is difficult. We must generally rely on examining various “behavioral correlates of consciousness” in judging whether entities other than ourselves are conscious – even with respect to other humans—since the only consciousness we can know with certainty is our own. Positing that matter and mind are two sides of the same coin explains the problem of consciousness insofar as it avoids the problems of emergence because under this approach consciousness doesn’t emerge. Consciousness is, rather, always present, at some level, even in the simplest of processes, but it “complexifies” as matter complexifies, and vice versa. Consciousness starts very simple and becomes more complex and rich under the right conditions, which in our proposed framework rely on resonance mechanisms. Matter and mind are two sides of the coin. Neither is primary; they are coequal.  We acknowledge the challenges of adopting this perspective, but encourage readers to consider the many compelling reasons to consider it that are reviewed elsewhere (Chalmers 1996, Griffin 1998, Hunt 2011, Goff 2017, Schooler, Schooler, & Hunt, 2011; Schooler, 2015).  Taking a position on the overarching ontology is the first step in addressing the Hard Problem. But this leads to the related questions: at what level of organization does consciousness reside in any particular process? Is a rock conscious? A chair? An ant? A bacterium? Or are only the smaller constituents, such as atoms or molecules, of these entities conscious? And if there is some degree of consciousness even in atoms and molecules, as panpsychism suggests (albeit of a very rudimentary nature, an important point to remember), how do these micro-conscious entities combine into the higher-level and obvious consciousness we witness in entities like humans and other mammals?  This set of questions is known as the “combination problem,” another now-classic problem in the philosophy of mind, and is what we describe here as the “easy part” of the Hard Problem. Our characterization of this part of the problem as “easy”[2] is, of course, more than a little tongue in cheek. The authors have discussed frequently with each other what part of the Hard Problem should be labeled the easier part and which the harder part. Regardless of the labels we choose, however, this paper focuses on our suggested solution to the combination problem.  Various solutions to the combination problem have been proposed but none have gained widespread acceptance. This paper further elaborates a proposed solution to the combination problem that we first described in Hunt 2011 and Schooler, Hunt, and Schooler 2011. The proposed solution rests on the idea of resonance, a shared vibratory frequency, which can also be called synchrony or field coherence. We will generally use resonance and “sync,” short for synchrony, interchangeably in this paper. We describe the approach as a general resonance theory of consciousness or just “general resonance theory” (GRT). GRT is a field theory of consciousness wherein the various specific fields associated with matter and energy are the seat of conscious awareness.  A summary of our approach appears in Appendix 1.  All things in our universe are constantly in motion, in process. Even objects that appear to be stationary are in fact vibrating, oscillating, resonating, at specific frequencies. So all things are actually processes. Resonance is a specific type of motion, characterized by synchronized oscillation between two states.  An interesting phenomenon occurs when different vibrating processes come into proximity: they will often start vibrating together at the same frequency. They “sync up,” sometimes in ways that can seem mysterious, and allow for richer and faster information and energy flows (Figure 1 offers a schematic). Examining this phenomenon leads to potentially deep insights about the nature of consciousness in both the human/mammalian context but also at a deeper ontological level.

Susanne Schilling*^

and 9 more

Jessica mead

and 6 more

The construct of wellbeing has been criticised as a neoliberal construction of western individualism that ignores wider systemic issues including increasing burden of chronic disease, widening inequality, concerns over environmental degradation and anthropogenic climate change. While these criticisms overlook recent developments, there remains a need for biopsychosocial models that extend theoretical grounding beyond individual wellbeing, incorporating overlapping contextual issues relating to community and environment. Our first GENIAL model \cite{Kemp_2017} provided a more expansive view of pathways to longevity in the context of individual health and wellbeing, emphasising bidirectional links to positive social ties and the impact of sociocultural factors. In this paper, we build on these ideas and propose GENIAL 2.0, focusing on intersecting individual-community-environmental contributions to health and wellbeing, and laying an evidence-based, theoretical framework on which future research and innovative therapeutic innovations could be based. We suggest that our transdisciplinary model of wellbeing - focusing on individual, community and environmental contributions to personal wellbeing - will help to move the research field forward. In reconceptualising wellbeing, GENIAL 2.0 bridges the gap between psychological science and population health health systems, and presents opportunities for enhancing the health and wellbeing of people living with chronic conditions. Implications for future generations including the very survival of our species are discussed.  

Mark Ferris

and 14 more

IntroductionConsistent with World Health Organization (WHO) advice [1], UK Infection Protection Control guidance recommends that healthcare workers (HCWs) caring for patients with coronavirus disease 2019 (COVID-19) should use fluid resistant surgical masks type IIR (FRSMs) as respiratory protective equipment (RPE), unless aerosol generating procedures (AGPs) are being undertaken or are likely, when a filtering face piece 3 (FFP3) respirator should be used [2]. In a recent update, an FFP3 respirator is recommended if “an unacceptable risk of transmission remains following rigorous application of the hierarchy of control” [3]. Conversely, guidance from the Centers for Disease Control and Prevention (CDC) recommends that HCWs caring for patients with COVID-19 should use an N95 or higher level respirator [4]. WHO guidance suggests that a respirator, such as FFP3, may be used for HCWs in the absence of AGPs if availability or cost is not an issue [1].A recent systematic review undertaken for PHE concluded that: “patients with SARS-CoV-2 infection who are breathing, talking or coughing generate both respiratory droplets and aerosols, but FRSM (and where required, eye protection) are considered to provide adequate staff protection” [5]. Nevertheless, FFP3 respirators are more effective in preventing aerosol transmission than FRSMs, and observational data suggests that they may improve protection for HCWs [6]. It has therefore been suggested that respirators should be considered as a means of affording the best available protection [7], and some organisations have decided to provide FFP3 (or equivalent) respirators to HCWs caring for COVID-19 patients, despite a lack of mandate from local or national guidelines [8].Data from the HCW testing programme at Cambridge University Hospitals NHS Foundation Trust (CUHNFT) during the first wave of the UK severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic indicated a higher incidence of infection amongst HCWs caring for patients with COVID-19, compared with those who did not [9]. Subsequent studies have confirmed this observation [10, 11]. This disparity persisted at CUHNFT in December 2020, despite control measures consistent with PHE guidance and audits indicating good compliance. The CUHNFT infection control committee therefore implemented a change of RPE for staff on “red” (COVID-19) wards from FRSMs to FFP3 respirators. In this study, we analyse the incidence of SARS-CoV-2 infection in HCWs before and after this transition.

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Amalia Alexe

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Globally, more than 200 million women become pregnant each year, most of whom receive medications despite limited information on their safe use during pregnancy. The paucity of drug safety data on pregnant and breastfeeding women stems from the routine exclusion of this population from clinical trials due to scientific, ethical, regulatory and legal concerns. Consequently, at the time of initial drug approval, there may be scant safety data to inform the drug benefit-risk balance to the mother, foetus, or infant. Although momentum is growing to include this underrepresented population in clinical trials, most information on drug exposure outcomes comes from data collected in the post-marketing setting. Regulatory guidance and legislation on medication use in pregnancy and breastfeeding were reviewed globally by TransCelerate IGR PV Pregnancy and Breastfeeding Team. ICH standards and CIOMS guidelines served as benchmarks for national safety regulations and guidance. The landscape assessment identified a lack of harmonisation of global regulations on research in pregnant and breastfeeding women. This editorial focuses on the ambiguities and lack of harmonisation in global regulations on post-marketing pregnancy and breastfeeding safety studies. There is currently no ICH standard to guide these types of safety studies and, in most regions reviewed, there are no clear regulations or guidance on when and how to conduct them. While a challenging undertaking, greater clarity and harmonisation would facilitate more timely completion of post-marketing pregnancy safety studies that would ultimately generate the critical data needed to optimize benefit-risk decisions for pregnant and breastfeeding women.

Sung-Seen Choi

and 2 more

Rationale: IMS has been widely used for the on-site detection of explosives. Air sampling method is applicable only when the concentration of explosive vapor is considerably high in the air, but vapor pressures of common explosives such as TNT, RDX, and PETN are very low. A test method for analyzing the vapor detection efficiency of explosives with low vapor pressure via IMS was developed using artificial vapor and collection matrices. Methods: Artificial explosive vapor was produced by spraying an explosive solution in acetone. Fifteen collection matrices of various materials with woven or nonwoven structure were tested. Two arrangements of horizontal and vertical positions of the collection matrices were employed. Explosive vapor collected in the matrix was analyzed through IMS. Results: Only three collection matrices of stainless steel mesh (SSM), polytetrafluoroethylene sheet (PFS), and lens cleansing paper (LCP) showed the TNT and/or RDX ion peaks at explosive vapor concentration of 49 ng/L. There was no collection matrix to detect PETN vapor at lower than 49 ng/L. For the PFS, TNT and RDX were detected at 49 ng/L vapor concentration. For the LCP, TNT and RDX were detected at vapor concentrations of 14 and 49 ng/L, irrespectively. Conclusions: The difference in the explosive vapor detection efficiencies could be explained by the adsorption and desorption capabilities of the collection matrices. The proposed method can be used for evaluating the vapor detection efficiency of hazardous materials with low vapor pressure.

Perihan Senel Tekin

and 1 more

Entrepreneurship is encouraged in every sector in the twenty-first century. In the field of health, nurse entrepreneurship emerges as an important issue in providing health services and improving public health. In this research, the development of entrepreneurial behavior in nursing in the world and a systematic examination of this development within the framework of academic knowledge are aimed. For this purpose, the types of entrepreneurship discussed in the last 10 years of research in the field of entrepreneurship in nursing and the methods, findings and results of these studies were examined. As a result of the search made in databases with high international recognition, 78.761 publications on nurse entrepreneurship were reached in the last ten years, and 30 articles were included in the final review. Classical, social, collective and intrapreneurship were discussed in these studies, which were examined in terms of entrepreneurship typology. As a result of the review, it was seen that the studies in the literature mostly focused on the opportunities and obstacles in front of entrepreneurial nurses. While collective entrepreneurship was included for the first time in the literature, it was found that eco-entrepreneurship and digital entrepreneurship have not yet been the subject of research on nurse entrepreneurship. However, it has been found that more research is needed on the relations between entrepreneurial nurses and non-governmental organizations, the incentives for increasing entrepreneurship and role modeling in entrepreneurship.

Saurav Misra

and 1 more

Chun-Hui Hu

and 2 more

COL4A2 is the encoding gene of the α2 chains of type IV collagen, and missense mutations of COL4A2 is correlated with multiple diseases. However, the association of COL4A2 mutations with epilepsy remains elusive. Here, we aimed to explore the function of COL4A2 mutations in the development of epilepsy. We performed a full spectrum of family-enhanced whole-exome sequencing on a family lineage and examined the genetic change on COL4A2 gene. The kainic acid (KA)-induced in vivo model and lipopolysaccharide (LPS)-induced in vitro model were established. The production and secretion of inflammation cytokines were measured by qPCR, western blotting, and ELISA assay. Neuron damages and astrocyte activation were checked by Nissle and GFAP immunofluorescence staining. One heterozygous variant was detected in the COL4A2 gene: c.1148C>T(p.Pro383Leu). COL4A2 mutation significant induced the exacerbation of seizures and impaired the learning and memory phenotype of the KA rats. COL4A2 mutation promoted the hippocampal astrocyte activation, enhanced hippocampal neuronal injury in the rats. The levels of iNOS, COX-2, IL-1β, IL-6, and TNF-α elevated in KA-treated rats and LPS-treated astrocytes were further induced by COL4A2 mutation. Mechanically, COL4A2 mutation stimulated JAK/STAT signaling. JAK2 and STAT3 phosphorylation was promoted by COL4A2 mutation and JAK/STAT signaling inhibitor WP1066 could blocked the effect in primary astrocytes and CTX-TNA cells. These data indicated that a new identified COL4A2 mutation contributed to astrocyte activation by activating JAK/STAT signaling in epilepsy. Our findings provided a novel mechanism and treatment target of COL4A2 related epilepsy.
Health information is a powerful vehicle for enhancing community health and it highlights both the problems and opportunities that exist for development. In Uganda, there are cases where decisions have been made without using health information in primary health care units. The existing capacity inadequacy to efficiently utilize information to track service use patterns over time to determine the impacts of policy and service delivery improvements in Uganda is one of the key weaknesses. With the support of the Ministry of Health, the government of Uganda is implementing projects to build and enhance the nation’s web-based national health information system (DHIS2), which collects data from all health systems and allows for making decisions based on evidence on the delivery of health services. The broad study objective was to establish the factors influencing the utilization of routine health information for decisions making among the health workers. The research design was based on an analytical cross-sectional design. The target population for this study was 260 health workers specifically targeting those involved in the use of routine utilization of health information. Purposive sampling was used to select the key informants and other respondents were selected using simple and stratified random sampling. The self-administered structured questionnaire and key informants’ interviews were used to collect data from respondents. The analysis of the quantitative data was done using descriptive statistics consisting of tables, bar graphs, pie charts, frequency, percentages, mean and standard deviations. Logistic regression analysis was conducted for establishing the association amongst the variables. The study established that technical factors (χ2=801.069; p=0.001), organizational factors (χ2=895.224; p=0.000), and behavioural factors (χ2=994.559; p=0.000) had a significant influence on utilization of routine health information for decision making. Talk of significant predictors of utilization of routine health information for decision making, technical factors (p = 0.013) had the greatest influence on utilization of routine health information for decision making among health workers at health facilities followed by organizational factors (p = 0.049). The study recommends that management of health facilities in Moyo district to create organizational culture through increased demand for and use of routine health information for evidence-based decision making in all aspects. The study further established areas of the routine health information system that requires to be reinforced and backed up to ensure the use of routine data in health facility to make decisions.

Asmahan Elgellaie

and 4 more

The pro-inflammatory cytokines IL-1α, IL-6 and TNF-α are associated with major depressive disorder, psychological distress, cardiovascular health, and obesity. However, there is limited research that has examined multiple associations between these variables, among individuals with major depressive disorder in comparison to a control cohort, including sex differences. In this study, data was analysed from 60 individuals with major depressive disorder and 60 controls, including plasma IL-1α, IL-6 and TNF-α, adiposity measures (body mass index; waist circumference), cardiovascular health indices (blood pressure; heart rate) and psychological symptoms (depressive severity; anxiety; hostility; stress). The cytokines were compared by group and sex, and correlated with measures of adiposity, cardiovascular health indices and psychological health. Plasma IL-1α and IL-6 were higher in major depressive disorder group versus control, but with a sex interaction for IL-6, with this group difference only among females. TNF-α did not differ between groups. IL-1α and IL-6 correlated with depressive severity, anxiety, hostility, and stress, while TNF-α correlated only with anxiety and hostility. Psychopathology was associated with IL-1α in males only, and with IL-6 and TNF-α in females only. None of the cytokines correlated with body mass index, waist circumference, blood pressure or heart rate. The result of group by sex interaction for IL-6, and sex specific associations between pro-inflammatory cytokines and psychometrics could be aetiologically important in depression interventions and treatments for females versus males, warranting further investigation.

Ziwei Ma

and 10 more

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Suoya Fan

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Between 81º30’ E and 83ºE the Himalayan range’s “perfect” arcuate shape is interrupted by an embayment. We hypothesize that thrust geometry and duplexing along the megathrust at mid-lower crustal depths plays a leading role in growth of the embayment as well the southern margin of the Tibetan plateau. To test this hypothesis, we conducted thermokinematic modeling of published thermochronologic data from the topographic and structural embayment in the western Nepal Himalaya to investigate the three-dimensional geometry and kinematics of the megathrust at mid-lower crustal depths. Models that can best reproduce observed cooling ages suggest that the megathrust in the western Nepal Himalaya is best described as two ramps connected by a long flat that extends further north than in segments to the east and west. These models suggest that the high-slope zone along the embayment lies above the foreland limb of an antiformal crustal accretion zone on the megathrust with lateral and oblique ramps at mid-lower crustal depths. The lateral and oblique ramps may have initiated by ca. 10 Ma. This process may have controlled along-strike variation in Himalayan-plateau growth and therefore development of the topographic embayment. Finally, we analyze geological and morphologic features and propose an evolution model in which landscape and drainage systems across the central-western Himalaya evolve in response to crustal accretion at depth and the three-dimensional geometry of the megathrust. Our work highlights the importance of crustal accretion at different depths in orogenic-wedge growth and that the mid-lower crustal accretion determines the location of plateau edge.

Xu Deng

and 1 more

This study focuses on the projections and time of emergence (TOE) for temperature extremes over Australian regions in the phase 6 of Coupled Model Intercomparison Project (CMIP6) models. The model outputs are based on the Shared Socioeconomic Pathways (SSPs) from the Tier 1 experiments (i.e., SSP1-2.6, SSP2-4.5, SSP3-7.0 and SSP5-8.5) in the Scenario Model Intercomparison Project (ScenarioMIP), which is compared with the Representative Concentration Pathways (RCPs) in CMIP5 (i.e., RCP2.6, RCP4.5 and RCP8.5). Furthermore, two large ensembles (LEs) in CMIP6 are used to investigate the effects of internal variability on the projected changes and TOE. As shown in the temporal evolution and spatial distribution, the strongest warming levels are projected under the highest future scenario and the changes for some extremes follow a “warm-get-warmer” pattern over Australia. Over subregions, tropical Australia usually shows the highest warming. Compared to the RCPs in CMIP5, the multi-model medians in SSPs are higher for some indices and commonly exhibit wider spreads, likely related to the different forcings and higher climate sensitivity in a subset of the CMIP6 models. Based on a signal-to-noise framework, we confirm that the emergence patterns differ greatly for different extreme indices and the large uncertainty in TOE can result from the inter-model ranges of both signal and noise, for which internal variability contributes to the determination of the signal. We further demonstrate that the internally-generated variations influence the noise. Our findings can provide useful information for mitigation strategies and adaptation planning over Australia.

Katherine Dagon

and 5 more

Extreme precipitation events, including those associated with weather fronts, have wide-ranging impacts across the world. Here we use a deep learning algorithm to identify weather fronts in high resolution Community Earth System Model (CESM) simulations over the contiguous United States (CONUS), and evaluate the results using observational and reanalysis products. We further compare results between CESM simulations using present-day and future climate forcing, to study how these features might change with climate change. We find that detected front frequencies in CESM have seasonally varying spatial patterns and responses to climate change and are found to be associated with modeled changes in large scale circulation such as the jet stream. We also associate the detected fronts with precipitation and find that total and extreme frontal precipitation mostly decreases with climate change, with some seasonal and regional differences. Decreases in Northern Hemisphere summer frontal precipitation are largely driven by changes in the frequency of different front types, especially cold and stationary fronts. On the other hand, Northern Hemisphere winter exhibits some regional increases in frontal precipitation that are largely driven by changes in frontal precipitation intensity. While CONUS mean and extreme precipitation generally increase during all seasons in these climate change simulations, the likelihood of frontal extreme precipitation decreases, demonstrating that extreme precipitation has seasonally varying sources and mechanisms that will continue to evolve with climate change.

Davide Tognin

and 8 more

Conventional engineering measures, such as surge barriers and mobile floodgates, are being adopted in many coastal cities worldwide, threatened by the increasing flooding hazard due to rising sea levels. Famous examples include London, the Netherlands, New Orleans, St. Petersburg and Venice. However, the question of how flood regulation affects the morphodynamic evolution of shallow tidal embayments still lingers. Storm-surge barriers may importantly modify the propagation of tides, surges and wind waves, changing sediment transport and, thus, the morphological evolution of regulated tidal environments, in particular in sediment-starved systems. Combining field data and numerical modelling, we investigate the effect of the Mo.S.E. storm-surge barriers, designed to protect Venice from flooding, on the morphodynamic evolution of the Venice lagoon. Artificial reduction of water levels within the lagoon affects the interaction between tide propagation and wind waves, increasing sediment resuspension on tidal flats. Resuspended sediment hardly accumulates on salt marshes, contributing to their vertical accretion and offsetting the negative effect of relative sea-level rise, owing to the reduction of marsh flooding determined by reduced water levels. Although barrier closures temporarily reduce the sediment export toward the open sea, this does not point to preserve the characteristic lagoonal morphology, hindering salt-marsh accumulation and promoting tidal-flat deepening and channel infilling. We conclude that the operations of flood barriers can promote a significant loss of geomorphological diversity, which will critically impact the ecosystem services provided by the shallow tidal environments they are meant to protect, thus increasing the costs related to their conservation and restoration.

Chao Gao

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Meandering channels are ubiquitous features in intertidal mudflats and play a key role in the eco-morphosedimentary evolution of such landscapes. However, the hydrodynamics and morphodynamic evolution of these channels are poorly known, and direct flow measurements are virtually nonexistent to date. Here, we present new hydroacoustic data collected synchronously at different sites along a mudflat meander located in the macrotidal Yangkou tidal flat (Jiangsu, China) over an 8-day period. The studied bend exhibits an overall dominance of flood flows, with velocity surges of about 0.8 m/s occurring immediately below the bankfull stage during both ebb and flood tides. Unlike salt-marsh channels, velocities attain nearly-constant, sustained values as long as tidal flows remain confined within the channel, and reduce significantly during overbank stages. In contrast, curvature-induced cross-sectional flows are more pronounced during overbank stages. Thus, a phase lag exists between streamwise and cross-stream velocity maxima, which limits the transfer of secondary flows and likely hinders the formation of curvature-induced helical flows along the entire meander length. Our results support earlier suggestions that the morphodynamics of intertidal mudflat meanders does not strongly depend on curvature-induced helical flows, and is most likely driven by high velocities and sustains seepage flows at late-ebb stages, as well as by other non-tidal processes such as waves and intense rainfall events. By unraveling complex flow structures and intertwined morphodynamic processes, our results provide the first step toward a better understanding of intertidal mudflat meanders, with relevant implications for their planform characteristics and dynamic evolution.
I recently showed that Mw5.6+ earthquakes occur due to (as the lithosphere rides on) vast waves of the Moon-driven and gravitationally aided 1–72h long-periodic Earth body resonance (EBR). Here I report a methodologically independent proof: observation of actual EBR waves in solid matter using continuous GPS (cGPS). Superharmonic resonance periods from the EBR’s 55’–15 days (0.303 mHz–0.771605 μHz) band are thus recoverable in spectra of ITRF2014 positional components solved kinematically from 30-s cGPS samplings. The signal is so pure, strong, and stable that even daylong components are always and only periodic with Earth resonance periods constantly 99%-significant and of very high fidelity (ϕ>>12); very low fidelity (ϕ<<12) characterizes overtones and undertones. The examined cGPS stations have diurnal EBR fingerprints: unique sets of ~13-18 EBR periods, most clearly formed during ~M6+ quiescence, enabling depiction of EBR orientation for real-time EBR mapping. Furthermore, weeklong component time series reveal complete EBR and unavoidable undertone series (with very high fidelity, too) as the signature of an EBR’s companion sympathetic resonance. Also, I demonstrate the concept of EBR mapping using the Mexico City–Los Angeles–San Francisco cGPS profile alongside a tectonic plate boundary, successfully depicting the preparation phase of the 2020 Puerto Rico Mw6.4–Mw6.6 sequence. I finish by showing that the EBR has triggered the 2019 Ridgecrest Mw6.4–Mw7.1, sequence too. EBR maps can now be produced — for seismic prediction and to unobscure (decouple EBR from) geophysical observables such as stress/strain. Applications of EBR include geophysical prospecting and detection at all scales and at any time.

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