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High density mapping of atrial insertion of retrograde decremental accessory pathway...
Philippe Maury
Quentin Voglimacci

Philippe Maury

and 6 more

July 21, 2021
We report the case of a reciprocating tachycardia using a purely retrograde decremental slow-conducting accessory pathway. High density 3D mapping of the atrial insertion reveals a large area of specific potentials at the level of the tricuspid annulus, which can be regarded as an accessory conduction network
Pooled molecular occurrence of Mycoplasma gallisepticum and Mycoplasma synoviae in po...
Miguel Angel Chaidez-Ibarra
Diana Z. Velazquez

Miguel Angel Chaidez-Ibarra

and 7 more

July 21, 2021
Worldwide, Mycoplasma gallisepticum (MG) and M. synoviae (MS) are the main agents responsible for chronic respiratory disease in poultry. Therefore, we conducted a systematic review and meta-analysis to estimate their occurrence. We searched electronic databases to find peer-reviewed publications reporting the molecular detection of MG and MS in poultry and used meta-analysis to estimate their pooled occurrence (combined flock and individual), aggregating results at the regional and national levels. We performed a subgroup meta-analysis for subpopulations (broilers, layers, breeders, and diverse poultry including turkeys, ducks, and ostriches) and used meta-regression with categorical modifiers. We retrieved 2,294 publications from six electronic databases and included 85 publications from 33 countries that reported 62 studies with 22,162 samples for MG and 48 studies with 26,413 samples for MS. The pooled occurrence was 38.4% (95% CI: 23.5-54.5) for MS and 27.0% (20.4-34.2) for MG. Among regions, Europe and Central Asia had the lowest occurrence for both pathogens, while MG and MS were highly prevalent in South Asia and sub-Saharan Africa, respectively. MG occurrence was higher in Algeria, Saudi Arabia, and Sudan, whereas China, Egypt, and Ethiopia reported a higher occurrence of MS. MS and MG were more prevalent in the breeders and layers (62.6% and 31.2%, respectively) than in diverse poultry. The year of publication, the sample size, and the level of ambient air pollution (measured indirectly by PM2.5) were associated with the occurrence of both mycoplasmas. Our study revealed a high and heterogeneous occurrence of MG and MS and justifies the need for an early detection and improved control measures to reduce the spread of these pathogens.
The Effects of Asthma on the Stress Oxidative, Inflammation, and Endothelial Dysfunct...
ali Arjmand Shabestari
fatemeh imanparast

ali Arjmand Shabestari

and 3 more

July 21, 2021
Background: Pulmonary vascular endothelial activation, inflammation, and stress oxidative have been implicated in adverse clinical outcomes of community-acquired pneumonia (CAP). Chronic lung problems such as asthma may affect the consequences of pneumonia.The present study aimed to assess the effects of asthma on the oxidative stress, inflammation, and endothelial dysfunction biomarkers in children pneumonia. Methods: This cross-sectional study was performed at Amir Kabir Hospital affiliated to Arak University of Medical Sciences, Arak, Iran. Participants were 25 children with severe CAP and asthma (group I), 25 children with severe CAP (group II), and 25 healthy children (group III) with 2 to 6 years of age. Fasting blood samples were taken to the assay of serum malondialdehyde (MDA), total antioxidant capacity (TAC), tumor necrosis factor-alpha (TNF-α), soluble vascular cell adhesion molecule-1 (sVCAM-1), and Plasminogen activator inhibitor-1 (PAI-1). Results: We observed a significant reduction in TAC in groups I and II compared with group III. This reduction was significantly higher in group I than in group II. Also, we observed a significant increase in MDA and TNF-α in groups I and II compared with group III. The increase in MDA was significantly higher in group I than in group II. VCAM-1 and PAI-1 as endothelial dysfunction biomarkers increased significantly in group I compared with groups II and III. Also, VCAM-1 and PAI-1 increased significantly in group II compared with groups III. Conclusions: Asthma can exacerbate the consequences of pneumonia in children by increasing oxidative stress, inflammation, and endothelial dysfunction.
Browsing herbivores improve the state and functioning of savannas: a model assessment...
Katja Irob
Niels Blaum

Katja Irob

and 7 more

July 21, 2021
Changing climatic conditions and unsustainable land use are perceived as major threats to savannas worldwide. In the past, land use in African savannas was dominated by livestock-farming as one of the major economic products, which led to degraded, shrub encroached pastures in many regions. One response to this widespread degradation is a shift from land use dominated by cattle to strategies characterized by animal compositions with more mixed feeding regimes and higher browser proportions. However, the consequences for ecosystem properties and processes remain so far largely unclear. We used the ecohydrological, spatially explicit savanna model EcoHyD to assess the impacts of two contrasting, herbivore-related land use strategies on a Namibian savannah: grazing versus browsing herbivores. We varied the densities of grazers and browsers and determined the resulting composition and diversity of the plant community, total vegetation cover, soil moisture and water use by plants. Our results show that properties making plants less attractive to herbivores were best adapted to different densities of grazing (cattle) or browsing (pure browsing wildlife) animals. Also, properties leading to a competitive advantage under limited water availability were among the dominant ones. Overall, the results are in line with our expectations: we found heavy shrub encroachment with a loss of the perennial grass matrix under high stocking rates of cattle. A novel and unexpected result was that regardless of the density of browsers, grass cover and plant functional diversity were significantly higher in wildlife scenarios. This increased grass cover, but also the higher total cover improved water uptake by plants. We conclude that in contrast to grazers, browsers even in high densities do not lead to ecosystem degradation, but rather sustain a diverse vegetation with high cover of perennial grasses over a long time, implying also a lower erosion risk and higher provision of ecosystem services.
Conservation laws and exact solutions for the generalized Ostrovsky equation using sy...
Sol Sáez

Sol Sáez

July 20, 2021
In this work we consider a generalized Ostrovsky equation depending on two arbitrary functions and we make an in-depth study of this equation. We obtain the Lie symmetries which are admitted by this equation and some exact solutions as a periodic or solitary waves, obtained through ordinary and partial differential equations. Also, by means of the concept of multiplier, we obtain a wide range of conservation laws which preserve properties of the generalized Ostrovsky equation.
Adoption of minimally invasive mitral valve surgery in the NHS. A blend of science an...
Megan Joffe
Steven Hunter

Megan Joffe

and 10 more

July 20, 2021
OBJECTIVES The objectives of this study were to understand the challenges faced by early adopters of MIS mitral surgery in the national health system in the United Kingdom. It was to (i) capture the significance of the scrutiny introduced by reporting surgeon specific results during the introduction of surgical innovation, (ii) understand how individual personality and behaviour helped these surgeons succeed despite, in many cases, little wider support, (iii) to help more surgeons adopt these patient-centred techniques. SETTING AND PARTICIPANTS The study is based on a qualitative exploration of the reported experiences of all ten early adopters of MIS cardiac surgery in the NHS between 2006-2016. Interviewees were recruited by invitation through their professional society (BISMICS). All interviewees consented to the process; ethical permission was not deemed necessary. RESULTS The experience of introducing surgical innovation into the NHS was unanimously noted to be difficult with few incentives and many systemic and institutional obstacles. Despite this there was a general belief in pushing forward with these patient centred procedures while accumulating the evidence to support it. CONCLUSIONS Individual determination, confidence, mental agility and self-reflection were seen as characteristics of those who were successful. All surgeons agreed that the reporting of surgeon specific results were not conducive to adoption of innovation in teams. Starting a new program as two surgeons appeared to help reduce perceived pressures. Surgical innovation and its early adoption are always likely to be difficult and needs to be recognised as such, within the NHS
Carcinoma en cuirasse associated to zosteriform metastasis from breast adenocarcinoma
Azza Ghanem
Refka FRIOUI

Azza Ghanem

and 5 more

July 20, 2021
Breast cancer is the first cancer associated with cutaneous metastasis (CM). The clinical presentation of these metastases is very broad. We report an original case of carcinoma en cuirasse associated with zosteriform metastasis that announced the developing of contralateral breast cancer.”
Numerical simulation analysis of the induced thrust on a char particle in reaction pr...
Shengyu  Zhou
Zhongjie Shen

Shengyu Zhou

and 5 more

July 20, 2021
The force exerted on particles is of great significance to the flow and reaction characteristics of particles in gasifier. In this study, the unbalanced thrust, especially its magnitude, of a single char particle induced by chemical reactions during combustion process is investigated numerically, based on the random distribution of active sites. It is revealed that the nonuniform distribution of active sites directly leads to the nonuniform release of gaseous products, which accounts for the net induced thrust of particles. The effects of active site ratio, ambient gas temperature and particle diameter on the induced thrust of reaction particle were investigated. The results show that the induced thrust on particles could be equal to the magnitude of particle gravity. The induced thrust decreases with the increase of active area and particle diameter. And it is enhanced with the increase of ambient temperature.
‘You’re on mute!’ Does paediatric CF home spirometry require physiologist supervision...
Emma Fettes
Mollie Riley

Emma Fettes

and 6 more

July 20, 2021
Introduction: The COVID-19 pandemic has accelerated the move towards home spirometry monitoring, including in children. Our aim was to determine whether the remote supervision of spirometry by a physiologist improves the technical quality and failure rate of the manoeuvres. Method: Children with cystic fibrosis who had been provided with NuvoAir home spirometers were randomly allocated to either supervised or unsupervised home spirometry following a detailed training session. Home spirometry was performed every 2 weeks for 12 weeks. Tests were assigned a quality factor (QF) using our laboratory grading system as per ATS/ERS standards, with tests marked from A to D, or Fail. In our laboratory we aim for QF A in all spirometry tests, but report results of QF B or C with a cautionary note. QF A was therefore the primary outcome, and QF A-C the secondary outcome. Results: 61 patients were enrolled; 166 measurements were obtained in the supervised group, and 153 in the unsupervised group. Significantly more measurements achieved QF A in the supervised compared to unsupervised group (89% vs 74%; p= <0.001) whilst proportions reaching grade A-C were similar (99% vs 95%; p=0.1). All significant declines in spirometry results had a clinical rather than technical reason. Family/patient feedback for both arms was very positive. Conclusion: These results suggest that home spirometry in children should ideally be remotely supervised by a physiologist, but acceptable results can be obtained if resources do not allow this, provided that training is delivered and results monitored according to our protocol.
The role of FFRCT in Aortic Surgery: Is this the future?
Abdul Ahmed
Mohammed Idhrees

Abdul Ahmed

and 2 more

July 20, 2021
Editorial
Evaluation of the renin-angiotensin-aldosterone system and neuroendocrine stress axis...
Mahshid Naghashpour
Maryam Adelipour

Mahshid Naghashpour

and 6 more

July 20, 2021
RAAS could play a substantial role in the pathophysiology of COVID-19. Also, the dynamics of the HPA axis may have changed in COVID-19. So, we aimed to assess RAAS and the HPA axis in COVID-19 suspicious outpatients referred to 16-hour comprehensive health centers in Abadan. Demographic and clinical data were collected. Serum cortisol and aldosterone measurements and blood grouping were done. Clinical symptoms of the positive PCR group were followed up on for four weeks. SPO2 was significantly lower in the positive PCR group, but the respiratory rate was significantly higher (P= 0.03 and P=0.001, respectively). Outpatients with the O blood group showed higher levels of cortisol in comparison to those with A and AB blood groups (P= 0.003 and P= 0.03 respectively) in the positive PCR group. Negative PCR individuals with the AB blood type had significantly higher levels of cortisol compared with those who had A (P= 0.02) and O (P=0.03) blood types. We saw significantly higher levels of aldosterone in males of the negative PCR group in comparison with females (P= 0.05). Cortisol (OR= 0.937, P= 0.033) and aldosterone (OR= 1.005, P= 0.020) levels had a decreasing and increasing effect on the chances of respiratory symptoms occurring over time, respectively. Also, over time, women were twice as likely as men to develop neurologic symptoms (OR= 0.530, P= 0.015). Cortisol and aldosterone are associated with the chance of respiratory symptoms occurring over time. However, the levels of these two markers do not seem to be related to the lower grades of COVID-19.
Hearing, voicing and healing: rivers as culturally located and connected
Sandra Wooltorton
Anne Poelina

Sandra Wooltorton

and 3 more

July 20, 2021
In this paper a collaborative writing group explores how we, two rivers, express ourselves over time, place and space, our energies long interpreted as veins and arteries carrying the Country’s life affirming blood. Voiced as River: I, River, this position reflects a worldview in which interrelationship with living river is normal, and River Spirit is ever-present. It is a position underpinned by Indigenous narratives as riverine expressions of place-based love. At times the paper is also voiced as writing group or individuals, with voices being interchanged where required for smooth reading. We see this as part of the decolonising process, which feels liberating and healing amongst the writers. Each writer is equally valued as co-creator, contributor, narrator and story teller. The two Rivers, being Martuwarra Fitzroy River (Kimberley, Western Australia), and Unamen Shipu Romaine River (North Shore, Québec, Canada) illustrate a common condition of being, through heritage, life, change and possibility. Through stories and voices, the socio-scientific implications of colonisation and lost connections become clear, considering the interaction, the dialogue and the cultural synthesis of living water systems that have always incorporated all life forms into rivers of life. As a way of navigating towards wholeness, Aboriginal knowledge systems and narratives for healing are used to bring together findings of this intercultural river learning journey.
Stepanov-like pseudo anti-periodicity and applications to semi-linear parabolic bound...
liu huoxia

liu huoxia

July 20, 2021
This paper is mainly devoted to the existence of pseudo anti-periodic solutions of parabolic boundary differential equations by the measure theory. A new class of functions called Stepanov-like (µ0,ν0)-pseudo anti-periodic functions is proposed, which generalizes the classical weighted pseudo anti-periodic functions in Stepanov sense. The completeness of the space composed of these functions is proved. Translation invariance and two composition theorems are also established. As an application different from parabolic equations with linear boundary conditions, one shows that semi-linear parabolic evolution equations with inhomogeneous boundary conditions admit a (µ0,ν0)-pseudo anti-periodic solution in interpolation and extrapolation spaces. An example is presented to verify the existence of pseudo anti-periodic solution.
Impact of Coronavirus Disease 2019 on Respiratory Surveillance and Explanation of Hig...
Heui Man Kim
Eun Jung Lee

Heui Man Kim

and 6 more

July 20, 2021
Background: After the detection of the first case of coronavirus disease 2019 (COVID-19) in South Korea on January 20, 2019, it has triggered three major outbreaks. To decrease the disease burden of COVID-19, social distancing and active mask wearing were encouraged, reducing the number of patients with influenza-like illness and altering the detection rate of influenza and respiratory viruses in the Korea Influenza and Respiratory Viruses Surveillance System (KINRESS). We examined the changes in respiratory viruses due to COVID-19 in South Korea and virological causes of the high detection rate of human rhinovirus (hRV) in 2020. Methods: We collected 52,684 oropharyngeal or nasopharyngeal swab samples from patients with influenza-like illness in cooperation with KINRESS from 2016 to 2020. Influenza virus and other respiratory viruses were confirmed using real-time RT-PCR. The weekly detection rate was used to compare virus detection patterns. Results: Non-enveloped virus (hRV, human bocavirus, and human adenovirus) detection rates during the COVID-19 pandemic were maintained. The detection rate of hRV significantly increased in 2020 compared with that in 2019 and was negatively correlated with number of COVID-19-confirmed cases in 2020. The distribution of strains and genetic characteristics in hRV did not differ between 2019 and 2020. Conclusions: The extremely low detection rate of enveloped viruses resulted from efforts to prevent the spread of COVID-19 in South Korea. The high detection rate of hRV may be related to resistance against environmental conditions as a non-enveloped virus and the long period of viral shedding from patients.
Agricultural Irrigation Induced Evaporative Water Loss in a Temperate Climate Study S...
Lincoln Grevengoed
Duane Hampton

Lincoln Grevengoed

and 2 more

July 20, 2021
Worldwide, significant agricultural activities take place in temperate climate zones In regions where groundwater is used for irrigation, water losses take place due to evaporation. Previous studies demonstrated the utility of stable oxygen and hydrogen isotopes in estimating evaporative water loss experienced during return flow back to an aquifer. Unlike arid regions where the other studies took place, this study examined the region around Kalamazoo, Michigan, the United States, which experiences a more temperate climate.. Irrigation in the Kalamazoo area primarily uses center-pivot systems supplied by wells, unlike flood irrigation in previous study areas. Water samples were taken periodically from wells close to center-pivot irrigation systems. Water losses due to evaporation were estimated using stable oxygen and hydrogen isotopes, which are effective tracers for water. This approach was possible in the Kalamazoo area since the distribution of oxygen and hydrogen isotopes in local precipitation, which is the source of groundwater recharge, is known based on years of measurements. The link between agriculture and meteorology is thus clear. Isotope analyses during the irrigation season suggest water loss due to evaporation is in the range of 9.1% and 14.3%. This is less than what was estimated by previous studies in arid climate zones. Evaporative water loss was greater at wells near cornfields than at wells that supplied other crop types. There was little expected correlation between the groundwater’s isotope ratio values and the change in chloride concentration. This is likely due to an external input of chloride from road salt used in winter months.
A Bayesian copula-based spatio-temporal method for multivariate drought risk analysis...
Xin Yang
Yongping Li

Xin Yang

and 1 more

July 20, 2021
In this study, a Bayesian copula spatio-temporal drought risk analysis (BCSDA) method is developed through coupling Bayesian copula and spatio-temporal analysis into a general framework. BCSDA can effectively identify drought characteristics and reveal the temporal and spatial variation, as well as analyze drought risk at different guaranteed rates based on the influence of multivariate interaction. Then, BCSDA is applied to the Balkhash Lake Basin (a typical arid watershed in Central Asia) for analyzing drought risk during 1901-2017. Major findings are: (i) Balkhash Lake Basin suffered 53 drought events in 1901-2017, and the most severe drought event occurred in October 1973 to January 1977, which lasted for 40 months and developed into an extreme drought during April 1975 to June 1976, affecting 335,800 square kilometers of the study basin; (ii) most of the drought events developed in the direction of east-west, and Lli River delta and the alluvial plain were the most severe of drought (47.2%), followed by the plateau desert area (28.3%) and the arid grassland in north of Balkhash Lake (24.5%); (iii) drought shows significant seasonality which usually began in spring and summer (64.2%) and ended in summer and autumn (66.0%); (iv) in Balkhash Lake Basin, multivariate characteristics (duration, severity and area) would significantly affect drought risk; (v) the range of drought risk would be [1.9%, 18.1%], [3.7%, 33.1%], [8.7%, 46.0%], [16.0%, 55.1%] and [27.6%, 59.8%] when guarantee rate is 0.99, 0.98, 0.95, 0.90 and 0.80.
Protocol for a systematic review of the diagnostic test accuracy of tests for IgE-med...
Jon Genuneit
Sashini Jayasinghe

Jon Genuneit

and 9 more

July 20, 2021
Background: The European Academy of Allergy and Clinical Immunology (EAACI) is in the process of updating the guidelines on the diagnosis and management of food allergy. The existing guidelines are based on a systematic review of the literature until 30th September 2012. Therefore, a new systematic review must be undertaken to inform the new guidelines. This systematic review aims to assess the accuracy of index tests to support the diagnosis of IgE-mediated food allergy. Methods: The databases Cochrane CENTRAL (Trials), MEDLINE (OVID) and Embase (OVID) will be searched for diagnostic test accuracy studies from 1st October 2012 to 30th June 2021. Inclusion and exclusion criteria will be used to select appropriate studies. Data from these studies will be extracted and tabulated, and then reviewed for risk of bias and applicability using the QUADAS-2 tool. All evaluation will be done in duplicate. Studies with a high risk of bias and low applicability will be excluded. Meta-analysis will be performed if there are three or more studies of the same index test and food. Results: A protocol for the systematic review and meta-analyses is presented and was registered using Prospero prior to commencing the literature search. Discussion: Oral food challenges are the reference standard for diagnosis but involve considerable risks and resources. This protocol for systematic review aims to assess the accuracy of various tests to diagnose food allergy, which can be useful in both clinical and research settings.
POPULATION STRUCTURE AND GENE FLOW IN THE SHEEPNOSE MUSSEL (PLETHOBASUS CYPHYUS) AND...
Kevin Roe
Sara Schwarz

Kevin Roe

and 1 more

July 20, 2021
North American freshwater mussel species have experienced substantial range fragmentation and population reductions. These impacts have the potential to reduce genetic connectivity among populations and increase the risk of losing genetic diversity. Thirteen microsatellite loci and an 883 bp fragment of the mitochondrial ND1 gene were used to assess genetic diversity, population structure, contemporary and historical migration rates, and population size changes across the range of the Sheepnose mussel (Plethobasus cyphyus). Population structure analyses reveal five populations, three in the Upper Mississippi River Basin and two in the Ohio River Basin. Sampling locations exhibit a high degree of genetic diversity and contemporary migration estimates indicate that migration between populations within river basins is occurring, although at low rates. but no migration is occurring between the Ohio and Mississippi river basins. No evidence of bottlenecks was detected, and almost all locations exhibited the signature of population expansion. Our results indicate that although anthropogenic activity has altered the landscape across the range of the Sheepnose, these activities have yet to be reflected in losses of genetic diversity. Efforts to conserve sheepnose populations should focus on maintaining existing habitats and fostering genetic connectivity between extant demes to conserve remaining genetic diversity for future viable Sheepnose populations.
Response of leaf functional traits of woody plants in central Guizhou to degraded kar...
Qi Wang
Li Rong

Qi Wang

and 6 more

July 20, 2021
1.In this study, the dominant woody plants in different degraded background plots in Puding, Guizhou Province were selected as the research objects. Six leaf functional traits(LT, LA, SLA, LDMC, LTD, Chlc) were measured to analyze the effects of soil characteristics on the leaf functional traits of vegetation in the region. 2.We observed that under the degraded environment of karst area, the plant leaves tended to increase, with the most significant change in the returned land; There were significant differences in plant traits under burning,burning felling and returning farmland, with the largest change range of LA, LTD and SLA, which could reach 121.90%, 118.08% and 86.00% respectively in the corresponding sample plots. 3.In the degraded plots, the leaf traits were significantly different among tree, shrub and liana species. In general, the interspecific variation of shrub and liana species was higher than that of tree species, and the community was in the early and middle stage of succession. 4.Soil properties under different degradation background were quite different,and there was a significant correlation between soil properties and vegetation leaf functional properties. Soil depth, soil nutrients and soil humidity were the key soil characteristic factors of plant leaf functional properties. 5.The results showed that the leaf traits of plant in degraded area showed large LA,small LT, low SLA and LTD, high LDMC and low Chlc, which tended to develop drought character combination. This paper reveals the internal differentiation succession law of degraded karst secondary forest in central Guizhou and provides scientific basis for the management and biodiversity protection of karst secondary forest.
Mini-invasive treatment of a congenital dacryocystocele by means of microdebrider mar...
Domenico di Furia
Lorenzo Pignataro

Domenico di Furia

and 5 more

July 20, 2021
Congenital dacryocystocele is a rare clinical condition, more commonly unilateral, secondary to the defective canalization of the nasolacrimal duct. In case of failure of conservative treatment, surgical marsupialization is recommended. We describe the case of a 40-days'old male newborn treated by means of microdebrider marsupialization.
Life-history attributes of Arctic-breeding birds drive uneven responses to environmen...
Daniel Ruthrauff
Vijay Patil

Daniel Ruthrauff

and 3 more

July 20, 2021
1. Animals exhibit varied life-history traits that reflect adaptive responses to their environments. For Arctic-breeding birds, traits like foraging guild, egg nutrient allocation, clutch size, and chick growth are predicted to be under increasing selection pressure due to rapid climate change and increasing environmental variability across high-latitude regions. 2. We compared four migratory birds (black brant [Branta bernicla nigricans], lesser snow geese [Chen caerulescens caerulescens], semipalmated sandpipers [Calidris pusilla], and Lapland longspurs [Calcarius lapponicus]) with varied life histories at an Arctic site in Alaska, USA, to understand how life-history traits help moderate environmental variability across different phases of the reproductive cycle. 3. We monitored aspects of reproductive performance related to the timing of breeding, reproductive investment, and chick growth from 2011–2018. 4. In response to early snow melt and warm temperatures, semipalmated sandpipers advanced their site arrival and bred in higher numbers, while brant and snow geese increased clutch sizes; all four species advanced their nest initiation dates. During chick rearing, longspur chicks were relatively resilient to environmental variation whereas warmer temperatures increased the growth rates of sandpiper chicks but reduced growth rates of snow goose goslings. These responses generally aligned with traits along the capital-income spectrum of nutrient acquisition and altricial-precocial modes of chick growth. Under a warming climate, the ability to mobilize endogenous reserves likely provides geese with relative flexibility to adjust the timing of breeding and the size of clutches. Warmer temperatures, however, may negatively affect the quality of herbaceous foods and slow gosling growth. 5. Species may possess traits that are beneficial during one phase of the reproductive cycle and others that may be detrimental at another phase, uneven responses that may be amplified with future climate warming. These results underscore the need to consider multiple phases of the reproductive cycle when assessing the effects of environmental variability on Arctic-breeding birds.
Long-term responses of benthic invertebrates to rotenone treatment
Gaute Kjærstad
Jo Arnekleiv

Gaute Kjærstad

and 3 more

July 20, 2021
Biological invasions are regarded as one of the largest threats to native biodiversity. The eradication of non-native parasites by culling of hosts are a controversial conservation strategy, particularly when using indiscriminate methods involving whole ecosystem collateral damage. While short-term effects are abundantly documented, long-term surveys are needed to detect potential wider ecosystem effects. Here, we report a six-year study on effects of the piscicide rotenone on invertebrate communities from a Norwegian water course using a Before-After-Control-Impact design. Kick-net samples of benthic invertebrates were collected from three lentic sampling stations and two lotic stations two to four times per year in both a control and a treated watershed. In general, only relatively minor short-term effects immediately after the treatment on species turnover, measured as temporal beta-diversity, of benthic invertebrates were observed both in lentic and lotic locations. However, the lotic fauna was temporarily severely negatively affected following a period of rotenone exposure from an upstream lake. Species turnover co-varied markedly between control and treatment locations, indicating that natural environmental variation override effects of rotenone treatment. Likewise, the abundance of invertebrate taxa varied considerably both over time and between control and treatment locations. Our study indicates minor short-term (i.e. < one month) or long-term (i.e. four years) effects of rotenone treatment on benthic invertebrates, but severe effects on the lotic fauna eight months after treatment. However, long-term effects are likely to be taxa-specific and vary depending on habitat connectivity and thus potential for re-colonization and will differ among locations and among taxa.
OASI Care Bundle
Mandie Scamell
James Thornton

Mandie Scamell

and 15 more

July 20, 2021
Sir,We welcome Gurol‐Urganci I and Bidwell et al’s evaluation of the impact of the care bundle to reduce obstetric anal sphincter injury (OASI) published in your August edition last year.[1] The article reports much needed evidence on the efficacy of an intervention that has already taken hold in many maternity services across the country.Despite the article’s timely nature, we would like to voice our disappointment in the quality of the evidence of support for the care bundle Meulen and Thakar et al provide, and the recommendations made. The article fails to consider important evidence in this area of maternity care prompting this response. In particular, the authors miss the opportunity to contextualise the relatively low-level evidence they take from five articles – reporting three Scandinavian cohort studies and one educational intervention study on manual assistance during the final part of the second stage of labour (including gripping the baby’s chin through the perineum) - with the compelling findings from the Cochrane review on Perineal techniques during the second stage of labour for reducing perineal trauma. [2] This omission is important because the Cochrane review indicates that warm compresses have a bigger positive effect on OASI than the OASI care bundle reported by Meulen and Thakar et al’s. Furthermore, the Cochrane review provides evidence suggesting that hands off the perineum may protect women from episiotomy; an outcome which Meulen and Thakar et al acknowledge remained unchanged despite the third component in the care bundle aiming to ‘use of episiotomy when clinically indicated’. The selective nature of the evidence quoted, undermines the credibility of inferences that can be made from the findings. We suggest therefore, that caution should be taken when reading the authors conclusions.Our second concern rests upon the authors failure to account for the surprisingly small positive effect of the care bundle compared with the Scandinavian studies they quote. Meulen and Thakar et al report a 0.3% decrease in OASI compared with a 3.6% reduction;[3]3% reduction;[4] a 2.6% reduction for low risk women;[5] and a 2.1% reduction in the various observational studies [6] Such a small effect in an open trial could easily be caused by ascertainment bias. Again, the quality of the previous Scandinavian studies make interpretation difficult but the marked difference in results between Scandinavia and England suggests caution should be taken when reading the authors conclusions.Our final concern pertains to women’s experience of the care bundle. Not only is the acceptability of the intervention not considered in this evaluation – a significant oversight given the conspicuous lack of evidence on this – there are ethical issues within the evaluation that deserve attention. The intervention description in figure 1 claims that women were informed about what could be done to reduce OASI. This does not appear to be entirely true given the lack of consideration of warm compresses and hands off to protect against episiotomy. Even more unsettling is the statement ‘MPP should be used unless the woman objects’, implying little consideration for autonomy and informed consent.For the above reasons, we are not only disappointed with the BJOG article but with the professional stakeholder investment in the intervention which seems to have been widely and uncritically supported, with some support even being somewhat evangelical, despite the limited evidence for support.Signatures,
A case of prenatal diagnosis of 16q24.3 microdeletion KBG syndrome and review of the...
tian qin deng
qingzhi liu

tian qin deng

and 4 more

July 20, 2021
Diagnosis of KBGS due to a high risk identified by early Down's syndrome screening has not been reported in previous studies, and the prominent KBGS phenotype and absence of specificity on early ultrasound examination also pose a challenge for genetic diagnosis.
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