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Predictive value of mid-trimester cervical measurement data combined with maternal de...
Mian Pan
Jun Zhang

Mian Pan

and 6 more

August 07, 2020
Objective: The purpose of this study was to develop a dynamic nomogram model to predict the risk of spontaneous preterm birth at <32 weeks in twin pregnancy. Design: A retrospective analysis and multicentre validation study Setting and Population: Women with twin pregnancies followed up in two tertiary medical centres from January 2017 to March 2019. Methods: Data on maternal demographic characteristics, transvaginal cervical length and funneling were extracted. The prediction model was constructed with independent variables determined by logistic regression analyses. The risk score was calculated according to the dynamic nomogram model. Main outcome measures: The risk of spontaneous preterm birth at <32 weeks in twin pregnancy. Results: In total, 1065 twin pregnancies were eligible for the study, of which the data of 764 cases (92 twin preterm cases (<32 weeks) and 672 control cases) were obtained from a tertiary medical centre as the training group and those of 301 cases (36 twin preterm cases (<32 weeks) and 265 control cases) from the other tertiary medical centre as the external validation group. Based on logistic regression analyses, we built a dynamic nomogram model with satisfactory discrimination in both the training group(C-index: 0.856, 95% CI: 0.813-0.899) and external validation group(C-index: 0.808, 95% CI: 0.751-0.865). The restricted cubic splines and ROC curve supported the performance of the prediction model. Conclusions: We developed and validated a dynamic nomogram model to predict the individual probability of preterm birth in twin pregnancy at <32 weeks.
Pregnancy in women with hemoglobin H disease in the Guangxi Zhuang Autonomous Region...
Dongmei Yang
Lingjie Deng

Dongmei Yang

and 6 more

August 07, 2020
Objective To investigate the fertility status and pregnancy outcome in women with hemoglobin H disease in southern China. Design Retrospective analysis. Setting The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi Population 28 young women with Hb H disease. Methods Clinic characteristics were included during their pregnancies over a 12-year period and their babies’ outcomes were assessed.. Main outcome measures Genotype, methods of conception and delivery, complications during pregnancies, and frequency of transfusion. Hb and serum ferritin levels. Babies’ birth weight, Apgar scores at 1 minute. Results Four genotypes, namely, - -/-α3.7, - -/-α4.2, - -/αWSα, - -/αQSα, and - -/αCSα, were found among these women. The most frequent ethnic background was Zhuang (57.14%). 59 pregnancies occurred. 56 conceptions were spontaneous. Six pregnancies were terminated because of Hb Bart’s hydrops fetalis. 44 resulted in successful deliveries of 46 neonates, and 17 were via cesarean section. The mean gestational period of delivery was 38 weeks, the rate of pregnancy complications was 50%. The majority of these women were never transfused before or during their pregnancy, except those with genotype –/αCSα. and the mean birth weight of the 46 neonates was 2815.00±503.26g. The mean hemoglobin concentration and median serum ferritin level were significantly decreased during the pregnancy. Conclusions Despite the good pregnancy outcome for women with Hb H disease, the pregnancy course is still considered high risk. Close monitoring of maternal and fetal conditions should be performed by multidisciplinary team to ensure the best outcome.
Respiratory viral infections by Non-influenza viruses are associated with more advers...
Ekta Gupta
Abhishek Padhi

Ekta Gupta

and 8 more

August 07, 2020
Background Respiratory viral infections are an important cause of acute respiratory tract infections. They are caused by both Influenza and non influenza viruses. Respiratory viral infections are known to be associated with severe clinical outcome especially in the critically ill. A constant surveillance is needed for early etiological identification which can help in timely and appropriate management. Methods In this retrospective study, clinical records of all adult liver disease patients with clinically confirmed ARI, whose request for respiratory viral testing were received in the virology laboratory during September 2016 - March 2019 were reviewed. Respiratory viruses were identified by real time PCR on FilmArray 2.0 instrument (BioFire Diagnostics, Utah, USA) using Respiratory panel as per the manufacturer’s instructions. Results Of the 603 patients of liver disease with clinically confirmed influenza like illness, over all incidence of respiratory viral infection was 24.3% (n= 147). Infections by non-influenza viruses (87, 59.1%) were more than influenza group of viruses. Mortality was higher in non influenza group (43, 49.4%) as compared to influenza (24, 40%) [p=0.015] being maximum in Rhinovirus, 22 (32.8%). Two peaks were observed in both influenza and non influenza groups, first in the months of January and February and the other one in August and October. Conclusion With the emergence of SARS- CoV-2 it has now become imperative for a constant surveillance of the non influenza viruses for early etiological identification of the respiratory viral infection for proper and timely management in the critically ill.
Specific immunoglobulin G4 inhibits Th2 cytokine production in allergic asthmatics wi...
Qiujuan Su
Nina Ren

Qiujuan Su

and 9 more

August 07, 2020
Background: The modulations of subcutaneous allergen immunotherapy (SCIT) on lymphocyte subsets and cytokine productions are not fully clarified. Objective: We investigated the changes of T-lymphocyte subsets and serum Dermatophagoides pteronyssinus specific immunoglobulin G4 (Der-p-sIgG4), and cytokine productions in allergic asthmatics during Der-p SCIT. Methods: This study involved 20 allergic asthmatics receiving 156-week Der-p SCIT, 20 patients without SCIT (non-SCIT). Symptom and medication scores (SMS), serum Der-p-sIgG4 levels, CD4+CD25+Foxp3+ T regulatory (Treg), CD4+IL-4-IFN-γ+ T-helper (Th) 1, CD4+IL-4+IFN-γ- Th2 lymphocyte percentage in peripheral blood mononuclear cells (PBMCs) with/without Der-p extract stimulation at weeks 0, 4, 12, 16, 52, 104, and 156 were measured. Serum from SCIT and non-SCIT patients were incubated with Der-p allergen and Der-p sensitized PBMCs. Levels of interleukin (IL) -4, IL-5, IL-10, IL-13, IL-17, interferon (IFN) -γ, tumor necrosis factor (TNF) -α and transfer growth factor (TGF) -β1 in supernatant were detected. Results: SCIT patients had significantly lower SMS after week 52. Der-p-sIgG4 levels in SCIT patients significantly increased at week 16 compared to non-SCIT subjects. CD4+IL-4+IFN-γ- Th2 percentage in SCIT patients showed a significant decrease from week 104 to 156 comparing to week 0, while no change was observed in CD4+CD25+Foxp3+ Treg and CD4+IL-4-IFN-γ+ Th1 percentage. IL-5, IL-13, IL-4, IL-17, and TNF-α levels in supernatant of Der-p-sensitized PBMCs, cultured with serum of SCIT patients after 16 weeks decreased significantly compared with non-SCIT patients, and showed significant reverse associations with Der-p-sIgG4 levels. Conclusion: SCIT down-regulated Th2 cytokine productions associated reversely with Dep-p-sIgG4 levels in Der-p allergic asthma patients.
Failure Behavior of the Thermal Treated Granite under Triaxial Cyclic Loading-unloadi...
Wen-Ling Tian
Sheng-Qi Yang

Wen-Ling Tian

and 3 more

August 07, 2020
The failure behavior of thermal treated granite under triaxial tiered cyclic loading-unloading compression has a significant effect on the safe and stable operation of HLW disposal repository. Therefore, the stress-strain curves, elastic modulus, Poisson’s ratio, plastic strain, dissipated energy and failure characteristic of the thermal treated granite specimens under triaxial compression were analyzed by experiment and numerical simulation. The results indicate that the elastic, Poisson’s ratio, axial plastic strain, dissipated energy and accumulative AE counts slightly increase with cyclic loading at initial loading and elastic deformation stage when T = 25 and 300°C, which means that less damage was induced by cyclic loading. However, damage occurred once cyclic loading was applied when T = 600°C. Radial strain even showed compressive characteristic in the initial stage, which indicates that grains adjustment occurred under triaxial cyclic loading-unloading compression. And, the compressive characteristic is more obvious with the increase of temperature or the decrease of confining pressure. The failure modes under triaxial cyclic loading are more complicated than that under triaxial monotonic loading, which make the shear plane rougher. Therefore, the residual strength is higher than that under monotonic loading. When T = 600°C, micro-crack continuously increases under uniaxial unloading and loading process, which result in a decrease of the peak strength under cyclic loading compared with that under monotonic loading.
Thirty-two COVID-19 cases preventively vaccinated with MMR: all mild course
Désirée Larenas-Linnemann

Désirée Larenas-Linnemann

August 07, 2020
We would like to report here on our clinical observations in 212 subjects, vaccinated in our Center since the start of the Coronavirus disease-2019 (COVID-19) pandemic, with the mumps-measles-rubeola (MMR) vaccine and of whom thirty-two have presented COVID-19, all with a remarkably mild course.In the light of the COVID-19 pandemic, observing the highly contagious and virulent nature of the virus, new to mankind and for which no actual treatment nor vaccination exists, we have been searching for methods to enhance innate immunity. Moreover, the pandemic started in our country just after a rise in measles cases had motivated the Ministry of Health to recommend measles re-vaccination. Aware of the existence of trained immunity we decided to apply this concept and from March 2020 onward recommend MMR vaccination, but with extra emphasis among family members of COVID-19 cases. In June 2020 the American Society for Microbiology (AMS) speculated in a press-release that “the MMR vaccine could serve as a preventive measure to dampen …. COVID-19 infection.”
Dimerization of the Mineralocorticoid Receptor Ligand Binding Domain by helix 9, 10 a...
Laurent Bianchetti
Deniz Sinar

Laurent Bianchetti

and 3 more

August 07, 2020
In vertebrates, the mineralocorticoid receptor (MR) is a steroid-activated nuclear receptor (NR) that plays essential roles in water-electrolyte balance and blood pressure homeostasis. It belongs to the group of oxo-steroidian NRs, together with the glucocorticoid (GR), progesterone (PR), and androgen (AR) receptors. Classically, these oxo-steroidian NRs homodimerize and bind to specific genomic sequences to activate gene expression. NRs are multi-domain proteins, and dimerization is mediated by both the DNA (DBD) and ligand binding (LBD) domains, with the latter thought to provide the largest dimerization interface. However, at the structural level, the LBD dimerization of oxo-steroidian receptors has remained largely a matter of debate. This is linked to the receptor refractory expression, purification and crystallization. As a result, there is currently no consensus on a common homodimer assembly across the 4 receptors, i.e. GR, PR, AR and MR, despite their sequence homology. Examining the available MR LBD crystals and using widely plebiscited tools such as PISA, PRISM and EPPIC, and the MM/PBSA method, we have determined that an interface mediated by the helices H9 and H10 of the LBD as well as by the F domain presents the features of a biological protein-protein interaction surface. This interface which has been observed in both GR alpha and MR crystals, distinguished itself among other contacts and provided for the first time a homodimer architecture that is common to both oxo-steroidian receptors.
Comparison of myelosuppression using the D-index between children and adolescents/you...
Satoru Matsushima
Ryoji Kobayashi

Satoru Matsushima

and 7 more

August 07, 2020
Background. Adolescents/young adults (AYAs) with acute lymphoblastic leukemia (ALL) are more likely to have chemotherapy-related complications than children. In addition, several reports have shown that infections account for most of the therapy-related mortality during cancer treatment in AYAs. Thus, we hypothesized that chemotherapy-induced myelosuppression is more severe in AYAs than in children, and the state of neutropenia was compared between children and AYAs using the D-index, a numerical value calculated from the duration and depth of neutropenia. Procedure. This study retrospectively analyzed 95 patients newly diagnosed with ALL at our institution between 2007 and 2019. Of these, 81 were children (< 15 years old) and 14 were AYAs (≥ 15 years old). The D-index and duration of neutropenia during induction chemotherapy for ALL were compared between children and AYAs. Results. The median D-index of children was significantly higher than that of AYAs (8,187 vs. 6,446, respectively, P = 0.017). Moreover, the median duration of neutropenia was also significantly longer in children than in AYAs (24.0 days vs. 11.5 days, respectively, P = 0.007). Conclusion. Contrary to our expectations, myelosuppressive toxicity during induction chemotherapy for ALL was more severe in children than in AYAs.
Population genetic structure and evolution of Batesian mimicry in Papilio polytes fro...
Yukuto Sato
Kaori Tsurui-Sato

Yukuto Sato

and 5 more

August 07, 2020
Batesian mimicry is a striking example of Darwinian evolution, in which a mimetic species resembles toxic or unpalatable model species, thereby, receiving protection from predators. In some species exhibiting Batesian mimicry, non-mimetic individuals coexist in the same population despite the benefits of mimicry, and the relative abundance of mimetic individuals in the population varies among localities. In a previous study, we found that the mimic ratios (MRs), which varied among the Islands, were likely to be explained by the model abundance of each habitat, rather than isolation-by-distance or phylogenetic constraint in the swallowtail butterfly, Papilio polytes, on the Ryukyu Islands in Japan. Because the previous study, however, was based on the mitochondrial DNA (mtDNA) that may sometimes mislead conclusion stemming from the inherent genetic properties, this possibility was reexamined based on hundreds of nuclear single-nucleotide polymorphisms (SNPs) of 95 P. polytes individuals from five Islands of the Ryukyus. We found that the population genetic and phylogenetic structures of P. polytes largely corresponded to the geographic arrangement of the habitat Islands, and the genetic distances among island populations significantly correlated with the geographic distances, which was not evident by the mtDNA-based analysis. The revised SNP-based genetic distances with a partial correlation approach revealed that the MRs of P. polytes were strongly correlated with the model abundance of each island, implying that negative frequency-dependent selection shaped and maintained the mimetic polymorphism. Taken together, we suggest that predation pressure, not neutral factors, is major driving force to determine the relative abundance of Batesian mimicry in P. polytes from the Ryukyus.
Population genomics and phylogeography of the boll weevil, Anthonomus grandis Boheman...
Tyler Raszick
C. Dickens

Tyler Raszick

and 9 more

August 07, 2020
Despite the success of the United States (US) Boll Weevil Eradication Program, the boll weevil, Anthonomus grandis Boheman (Coleoptera: Curculionidae), remains a threat to cotton production in the southern US and is arguably the most important cotton pest in Central and South America. Management of this species is complicated by the existence of morphologically similar variants and re-infestations of areas where eradication had been successful. To date, no study has applied a high-throughput sequencing approach to better understand the population genetic structure of the boll weevil. Furthermore, only a single study has investigated genetic relationships between populations in North and South America. Here, we used double digest restriction site-associated DNA sequencing (ddRADseq) to resolve the population genomic structure of the boll weevil in the southern US, northern Mexico, and Argentina, test the two-form and three-form hypotheses of boll weevil variation in North America using a phylogeographic approach, and determine the relationship of the South American populations to the North. Our results supported the two-form hypothesis of boll weevil variation in North America wherein there are two major genetic lineages – one consisting of populations found geographically west of the Sierra Madre Occidental mountain range and the second consisting of populations found to the east – both are highly sub-structured across space and time. Boll weevil populations from Argentina were more closely related to the eastern lineage, suggesting a range expansion by the eastern lineage, but additional sampling across Central and South America is needed to determine a probable origin.
On the comparative biology of mammalian telomeres: Telomere length co-evolves with bo...
Michael Le Pepke
Dan Eisenberg

Michael Pepke

and 1 more

August 07, 2020
Telomeres, the short repetitive DNA sequences that cap the ends of linear chromosomes, shorten during cell division and are implicated in senescence in most species. Telomerase can rebuild telomeres but is repressed in many mammals that exhibit replicative senescence, presumably as a tumor suppression mechanism. It is therefore important that we have an accurate understanding of the co-evolution of telomere biology and life-history traits that has shaped the diversity of senescence patterns across species. Gomes et al. (2011) produced a large data set on telomere length (TL), telomerase activity, body mass and lifespan among 57 mammal species. We re-analyzed their data using the same phylogenetic multiple regressions and with several additional analyses to test the robustness of findings. We found substantial inconsistencies in our results compared to Gomes et al.’s. Consistent with Gomes et al. we found an inverse association between TL and lifespan. Contrary to the analyses in Gomes et al., we found a generally robust inverse association between TL and mass, and only weak non-robust evidence for an association between telomerase activity and mass. These results suggest that shorter TL may have been selected for in larger and longer-lived species–likely as a mechanism to suppress cancer. We support this hypothesis by showing that longer telomeres predict higher cancer risk across 22 species. Furthermore, we find that domesticated species have longer telomeres. Our results call into question past interpretations of the co-evolution of telomere biology and life-history traits and stress the need for careful attention to model construction.
Investigating sound through vibrations
Aminat Ajose

Aminat Ajose

August 14, 2020
Introduction In this hands on lesson, learners will explore sound waves through the concept of vibrations. They will investigate how sound travels through string and use this knowledge to design their own telephone using a paper cup and a string. Lesson Duration: 50 minutesLesson ObjectivesLearners should be able to describe how sound travels in different media. Learners will work collaboratively in pairs and small groups to carry out simple  investigations about sound waves. Learners should use tools and materials to design and build a device that uses sound to communicate.  Learners should understand that technology has helped people communicate over long distances.Educational Standards NGSS:   Connections by topic Physical Science: 1. Waves: Light and Sound   Connections by disciplinary core ideas: Physical Science: 1‐PS4 Waves and Their Applications in Technologies for Information  transfer   Connections by scientific & engineering practices  1. Asking questions & defining problems  3. Planning and carrying out investigations  6. Constructing explanations and designing solutions   Connections by crosscutting concepts 2. Cause and effect: Mechanism and explanation                               7. Stability and change   Connections by performance expectation: 1‐PS4‐1. Plan and conduct investigations to provide evidence that vibrating materials  can make sound and that sound can make materials vibrate.
HCM-AF-Risk Model to Identify Cases and Predictors of Atrial Fibrillation in Hypertro...
Moumita Bhattacharya
Dai-Yin Lu

Moumita Bhattacharya

and 9 more

August 07, 2020
Background AF in HCM is associated with high stroke risk despite low CHA2DS2-VASc scores. Hence, there is need to understand AF pathophysiology and predict AF in HCM. We develop/apply a data-driven, machine learning-based method to identify AF cases and clinical features associated with AF in HCM, using electronic health record (EHR) data. Methods Patients with documented paroxysmal/ persistent/permanent AF (n=191) were considered AF cases, and the remaining patients in sinus rhythm (n=640) were tagged as No-AF. We evaluated 93 clinical variables; the most informative variables useful for distinguishing AF from No-AF cases were selected based on the 2-sample t-test and information gain criterion. Results We identified 18 highly informative clinical variables: 11 are positively associated (e.g. LA-diameter, LV-diastolic dysfunction, LV-LGE), and 7 are negatively correlated (e.g. several exercise parameters) with AF in HCM. Next, patient records were represented via these 18 variables. Data imbalance resulting from the relatively low number of AF cases was addressed via a combination of over- and under-sampling strategies. We trained and tested multiple classifiers under this sampling approach, showing effective classification. Specifically, an ensemble of logistic regression and naïve Bayes classifiers, trained based on the 18 variables and corrected for data imbalance, proved most effective for separating AF from No-AF cases (sensitivity=0.74, specificity=0.72, C-index=0.80). Conclusions Our model (HCM-AF-Risk Model), the first machine learning-based method for identification of AF cases in HCM, demonstrates good performance, and suggests that AF is associated with a more severe cardiac HCM-phenotype.
A new interpretation of non-pulmonary vein substrates of the left atrium in patients...
Mariano Rillo
Zefferino Palamà

Mariano Rillo

and 11 more

August 07, 2020
Background. Substrate analysis of the left atrium in patients undergoing atrial fibrillation ablation has limitations when performed by means of simple bipolar acquisition. Objective. To evaluate the incidence of low-voltages (LV) through maps constructed by means of various catheters:multipoltar (MC), omnipolar (OC) and circular catheters (CMC) with the 3D electro-anatomical systems (3d-S) CARTO3 and Ensite-Precision. Methods. To assess LV we acquired maps by means of CMC and MC in the voltage range 0.05-0.5 mV in 70 patients in sinus rhythm. In case of OC only, we made an intra-patient comparison of bipolar maps constructed in along, across and HD-Wave configurations by means of Ensite-Precision in the ranges of 0.05-0.5 mV and 0.5-1.0 mV. Basing on this comparison, we chose the range that best identified LV and characterized patchy fibrosis by analyzing a set of different colors (qualitative analysis). Finally, we performed a quantitative analysis of LV by applying the qualitative characteristics described above. Results. Basing on our settings, the optimal range for OC was 0.3-0.6 mV. OC revealed smaller LV areas than MC (p <0.05 or p <0.001), except in the lateral wall. No significant differences were observed between CMCs. The same rates of AF recurrence were found for OC and MC during the follow-up period. Conclusions.In our experience, OC does not present the limits of bipolar HD maps, though further studies are needed in order to confirm that 0.3-0.6 mV as LV optimal voltage range.
Anaesthetic Management of a Neonate with an Intrapericardial Teratoma: A Case Report
Ying Lu-Boettcher
Prabhat Koppera

Ying Lu-Boettcher

and 2 more

August 06, 2020
We describe the anaesthetic management of a 4-day-old premature infant presenting for urgent resection of a massive posterior intrapericardial teratoma. Anaesthetic challenges include anticipating cardiopulmonary collapse upon induction and hemodynamic instability associated with blood loss or tumor manipulation. Premature infants present unique challenges due to patient-to-tumor size discrepancy.
Opioid Response in an Individual with Altered CYP2D6 Activity: Implications of a Phar...
Tyler Ballinghoff
Kevin Bain

Tyler Ballinghoff

and 5 more

August 06, 2020
The benefits of opioid use in older adults to manage chronic non-cancer pain must outweigh the risks as these individuals are more susceptible to the side effects and drug interactions associated with opioids. Pharmacogenomic testing supports clinicians to select an appropriate opioid therapy while minimizing these risks.
Carbamazepine induced Stevens-Johnson Syndrome (SJS) due to missed history of mast ce...
Tamer Zaalouk
zouheir Bitar

Tamer Zaalouk

and 3 more

August 06, 2020
Stevens-Johnson Syndrome (SJS) happen as a result of infection, side effects to medications or of unknown etiology. Carbamazepine is a common cause (SJS). Good history taking is crucial if clinically indicated treatment with carbamazepine. carbamazepine should be avoided with previous history of severe drug reaction like mast cell activation syndrome.
An Efficient Algorithm for Community Detection in Complex Weighted Networks
Leila Masooleh
Jeffrey Arbogast

Leila Masooleh

and 4 more

August 06, 2020
Community detection decomposes large-scale, complex networks ‘optimally’ into sets of smaller sub-networks. It finds sub-networks that have the least inter-connections and the most intra-connections. This article presents an efficient community detection algorithm that detects community structures in a weighted network by solving a multi-objective optimization problem. The whale optimization algorithm is extended to enabe it to handle multi-objective optimization problems with discrete variables and to solve the problems on parallel processors. To this end, the population’s positions are discretized using a transfer function that maps real variables to discrete variables, the initialization steps for the algorithm are modified to prevent generating unrealistic connections between variables, and the updating step of the algorithm is redefined to produce integer numbers. To identify the community configurations that are Pareto optimal, the non-dominated sorting concept is adopted. The proposed algorithm is tested on the Tennessee Eastman process to show its application and performance.
A spatially resolved model for pressure filtration of edible fat slurries
Harry Van den Akker
Doedo Hazelhoff Heeres

Harry Van den Akker

and 2 more

August 06, 2020
A spatially resolved 1-D pressure filtration model was developed for a slurry of edible fat crystals. The model focuses on the expression step in which a cake is compressed to force the liquid through a filter cloth. The model describes the local oil flow in the shrinking cake modeled as a porous nonlinear elastic medium existing of two phases, viz. porous aggregates and inter-aggregate liquid. Conservation equations lead to a set of two differential equations (vs time and vs a material coordinate ) for two void ratios, which are solved numerically by exploiting a finite-difference scheme. A simulation with this model results in a spatially resolved cake composition and in the outflow velocity, both as a function of time, as well as the final solid fat contents of the cake. Simulation results for various filtration conditions are compared with experimental data collected in a pilot-plant scale filter press.
COVID-19: A Perspective from Iran
Zargham Hossein Ahmadi
Mostafa Mousavizadeh

Zargham Hossein Ahmadi

and 4 more

August 06, 2020
The coronavirus disease 2019 (COVID-19) pandemic has presented unique challenges to international health care systems. Management of the current pandemic puts a huge strain on health care sectors and leads to new strategies conducting by health care systems in countries across the world. In the present article, we review the epidemiologic data, Iranian health care system response, as well as the effects of COVID-19 pandemic on cardiac surgery practice in Iran
No gas source, no problem: pre-existing embolism may affect non-pressure driven embol...
Xinyi Guan
Luciano Pereira

Xinyi Guan

and 4 more

August 06, 2020
Embolism spreading in dehydrating angiosperm xylem is driven by gas movement between embolised and sap-filled conduits. Here, we examine how proximity to pre-existing embolism and hydraulic segmentation affect embolism propagation. Based on the optical method, we compared xylem embolism resistance between detached leaves and leaves attached to branches, and between intact leaves and leaves with minor veins cut (n = 6 species). Moreover, we directly compared the optical and pneumatic method on detached leaves. Embolism resistance of detached leaves was significantly lower than leaves attached to stems, except for two species with all vessels ending in their petioles. Cutting of minor veins showed embolism spreading in narrow vessels near the cuts prior to wide vessels in major veins. Moreover, embolism spreading between open and intact vessels occurred at largely similar xylem water potentials than embolism spreading between intact vessels, resulting in strong similarity between the optical and pneumatic method. We conclude that embolism spreading may depend on a direct connection to pre-existing embolism as gas source, is not exclusively pressure-driven, and indirectly related to conduit size. Hydraulic segmentation, however, can minimise embolism spreading due to confined and/or poorly interconnected conduits, which may increase hydraulic safety by slowing down gas diffusion.
Utility of three-dimensional transesophageal echocardiography to guide transseptal po...
Dylan Addis
Bo Wang

Dylan Addis

and 5 more

August 06, 2020
A patient with heart failure due to dilated ischemic cardiomyopathy presented in cardiogenic shock for institution of veno-arterial extracorporeal membrane oxygenation as a bridge to cardiac transplantation. To provide adequate venous drainage and simultaneous decompression of the left atrium (indirect left ventricular venting) a single venous cannula was placed across the interatrial septum so the distal orifice and side ports were located within the left atrium and the proximal set of side ports at the cavoatrial junction. Three-dimensional transesophageal echocardiography demonstrated utility in guiding cannula placement and appropriate positioning within the left atrium.
Modelling of the changes in land cover in the forest of Sidi Bel'Abbes between 1987 a...
ayache abbassia
hellal benchaabane

ayache abbassia

and 3 more

August 06, 2020
The aim of our study is to know the rate of restoration, the reconstitution of the forest landscape and the impact of fires on the resilience of the soils of the Tenira forest. The frequent fires in the latter are one of the main major disruptive factors for the various components of the soil, regeneration and their dynamics. The uses of remote sensing data reduce the cost and time required to assess damage in the forest. It periodically and automatically provides information on very large areas and on several spectral bands. Our approach is based on the chronic study of this forest through the use of landsat sensor data, after collecting real field data. A supervised classification was applied to the selected images in order to identify the types of soils and the vegetation. The analysis of the results obtained showed remarkable of dominance agricultural soils of the type calcisols, calcaric fluvisols and the regeneration of the forest cover in the study area. There is also an increase areas cleared for agriculture which has accelerated soil erosion in this region. Indeed, the intensification of crops requires an increase in inputs which can lead to a decrease in the biological activities of the soil, in particular earthworms. This type of vegetation existing after this fire; indicates the low water storage capacity and the high risk of erosion. The final results generally showed that the rate of recovery of land use and type of soils in the Tenira forest has changed considerably.
Was the COVID-19 pandemic avoidable? A call for a “solution-oriented” approach in pat...
ROCHE Benjamin
Andres Garchitorena

ROCHE Benjamin

and 8 more

August 06, 2020
Concerns about the prospect of a global pandemic have been triggered many times during the last two decades. These have been realized through the current COVID-19 pandemic, due to a new coronavirus SARS-CoV2, which has impacted almost every country on Earth. Here, we show how considering the pandemic through the lenses of the evolutionary ecology of pathogens can help better understand the root causes and devise solutions to prevent the emergence of future pandemics. We call for better integration of these approaches into transdisciplinary research and invite scientists working on the evolutionary ecology of pathogens to contribute to a more “solution-oriented” agenda with practical applications, emulating similar movements in the field of economics in recent decades.
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