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EVALUATION OF THE INFECTION AWARENESS OF DENTISTS DURING COVID-19 PANDEMIC
SANAZ SADRY
Zeynep Sapan

SANAZ SADRY

and 1 more

January 14, 2021
Background: The present study aims to investigate the state of sterilization, disinfection and infection control of dentists during the COVID-19 pandemic. Methods: The study involved 310 dentists, who were asked to fill in a 19-question, multiple-choice survey on sterilization, disinfection and infection control. The survey results were evaluated statistically using chi-square test. Results: An investigation of the changes in working conditions and occupational experience during the pandemic period showed that 86.7% of the physicians who quit are the ones with occupational experience of 0 to 6 years. 89.3% of the physicians who answered “No idea” to the question about sterilization methods consist of physicians with over 20 years of experience, while 7.1% of them are physicians with 6-10 years of experience. Conclusion: Dentistry is the highest risk profession in the COVID-19 pandemic. And dentists need to reduce this risk by utilizing personal protective equipment and adopting the most appropriate disinfection and sterilization measures. Key Words: Disinfection, dentistry, sterilization.
Numerical Solution of Schrodinger Equation for Rotating Morse Potential using Matrix...
Aditi Sharma
O S K Sastri

Aditi sharma

and 1 more

January 14, 2021
In this paper, an elegant and easy to implement numerical method using matrix mechanics approach is proposed, to solve the time independent Schrodinger equation (TISE) for Morse potential. It is specifically applied to non-homogeneous diatomic molecule HCl to obtain its rotating-vibrator spectrum. While matrix diagonalization technique is utilised for solving TISE, model parameters for Morse potential are optimized using variational Monte-Carlo (VMC) approach by minimizing χ 2 − value. Thus, validation with experimental vibrational frequencies is completely numerical based with no recourse to analytical solutions. The ro-vibrational spectra of HCl molecule obtained using the optimized parameters through VMC have resulted in least χ 2 − value as compared to those determined using best parameters from multiple regression analysis of analytical expressions. Numerical algorithm for solving the Hamiltonian matrix has been implemented utilizing Free Open Source Software (FOSS) Scilab and simulation results are matching well with those obtained using analytical solutions from Nikiforov-Uvarov (NU) method and asymptotic iteration method (AIM).
Ethanol resistance in Drosophila melanogaster has increased in parallel cold-adapted...
Quentin Sprengelmeyer
John E Pool

Quentin Sprengelmeyer

and 1 more

January 14, 2021
Understanding the genetic properties of adaptive trait evolution is a fundamental crux of biological inquiry that links molecular processes to biological diversity. Important uncertainties persist regarding the genetic predictability of adaptive trait change, the role of standing variation, and whether adaptation tends to result in the fixation of favored variants. Here, we use the recurrent evolution of enhanced ethanol resistance in Drosophila melanogaster during this species' worldwide expansion as a promising system to add to our understanding of the genetics of adaptation. We find that elevated ethanol resistance has evolved at least three times in different cooler regions of the species' modern range - not only at high latitude but also in two African high altitude regions - and that ethanol and cold resistance may have a partially shared genetic basis. Applying a bulk segregant mapping framework, we find that the genetic architecture of ethanol resistance evolution differs substantially not only between our three resistant populations, but also between two crosses involving the same European population. We then apply population genetic scans for local adaptation within our quantitative trait locus regions, and we find potential contributions of genes with annotated roles in spindle localization, membrane composition, sterol and alcohol metabolism, and other processes. We also apply simulation-based analyses that confirm the variable genetic basis of ethanol resistance and hint at a moderately polygenic architecture. However, these simulations indicate that larger-scale studies will be needed to more clearly quantify the genetic architecture of adaptive evolution, and to firmly connect trait evolution to specific causative loci.
Functional relationship between woody plants and insect communities in response to Bu...
Zhuang Wang
Lijuan Zhao

Zhuang Wang

and 6 more

January 14, 2021
To study the effect of the invasion of Bursaphelenchus xylophilus on the functional relationship between woody plants and insect communities, the populations of tree species and insect communities were investigative in the Masson pine forests with different infestation durations of B. xylophilus. In this study, the number of Pinus massoniana began to decrease sharply, whereas the total number of other tree species in the arboreal layer increased gradually with the infestation duration of B. xylophilus. The principal component analysis ordination biplot shows that there was a significant change in the spatial distribution of woody plant species in different Masson pine forest stands. Additionally, a total of 7,188 insect specimens was obtained. The insect population showed an upward trend in stand types with the increase of pine wilt disease infection periods, which demonstrated that the insect community had been significantly affected by the invasion of B. xylophilus. The structure of insect functional groups changed from herbivorous (He) > omnivorous (Om) > predatory (Pr) > parasitic (Pa) > detritivorous (De) in the control stand to He > Pa > Om, De > Pr after B. xylophilus infestation in the forests. The results showed that the populations of He, Pa, and De increased after the invasion of B. xylophilus, but the populations of Pr decreased. Moreover, the redundancy analysis ordination bi-plots reflected the complicated functional relationship between woody plant communities and insects after the invasion of B. xylophilus. The present study provides insights into the changes in the community structure of woody plants and insects, as well as the functional relationship between woody plant communities and insect communities after invasion of B. xylophilus.
Den characteristics and ecological significance of Marmota himalayana on the Qinghai-...
Shulin Wang
Fujiang Hou

Shulin Wang

and 1 more

January 14, 2021
Dens are places for cavernicolous animals to hibernate, reproduce, and avoid predators and harsh weather conditions, and thus they have a vital impact on their survival. M. himalayana is the main large cavernicolous rodent on the Qinghai-Tibet Plateau. The analysis of den traits and their ecological functions can reveal mechanisms by which marmots have adapted to their environment, which is important for further understanding the ecological significance of this species. From July to August 2019 (warm season), we used unmanned aerial vehicles to fly at low altitudes and slow speeds to locate 131 marmot burrows (45 on shaded slopes, 51 on sunny slopes, and 35 on flat areas) in the northeastern Qinghai-Tibet Plateau. We then measured the physical characteristics (den density, entrance size, first tunnel length, volume, orientation and plant characteristics near the den entrance) of these dens on site. The physical parameters of the M. himalayana dens showed that they function to protect the marmots from natural enemies and bad weather, provide good drainage, and maintain a stable microclimate around the entrance. This is a result of the marmot’s adaptation to the harsh environment (cold and humidity) of the Qinghai-Tibet Plateau.
A Paramount Problem Solved at Last: Paramagnetic Catalysis of Ortho-Para Hydrogen Con...
Bretislav Friedrich

Bretislav Friedrich

January 14, 2021
A document by Bretislav Friedrich, written on Authorea.
Quantum Phases and Chern-Simons Geometrics for the generation of a ligand targeting C...
Ioannis Grigoriadis

Ioannis Grigoriadis

January 14, 2021
SARS coronavirus 2 (SARS-CoV-2) in the viral spike (S) encoding a SARS-COV-2 SPIKE D614G mutation protein predominate over time in locales revealing the dynamic aspects of its key viral processes where it is found, implying that this change enhances viral transmission. It has also been observed that retroviruses infected ACE2-expressing cells pseudotyped with SG614 that is presently affecting a growing number of countries markedly more efficiently than those with SD614. The availability of newer powerful computational resources, molecular modeling techniques, and cheminformatics quality data have made it feasible to generate reliable algebraic calculations to design new chemical entities, merging chemicals, recoring natural products, and a lot of other substances fuelling further development and growth of this AI-quantum based drug design field to balance the trade-off between the structural complexity and the quality of such biophysics predictions that cannot be obtained by any other method. In this paper, we strongly combine topology geometric methods targeting at the atomistic level the protein apparatus of the SARS-COV-2 virus that are simple in machine learning anti-viral characteristics, to propose computer-aided rational drug design strategies efficient in computing docking usage, and powerful enough to achieve very high accuracy levels for this in-silico effort for the generation of the AI-Quantum designed molecule the RoccustyrnaTM small molecule, a multi-targeting druggable scaffold (1S,2R,3S)‐2‐({[(1S,2S,4S,5R)‐4‐ethenyl‐4‐sulfonylbicyclo[3.2.0]heptan‐2‐yl]oxy}amino)‐3‐[(2R,5R)‐5‐(2‐methyl‐6‐methylidene‐6,9‐dihydro‐3H‐purin‐9‐yl)‐3‐methylideneoxolan‐2‐yl]phosphirane‐1‐carbonitrile targeting the COVID-19-SARS-COV-2 SPIKE D614G mutation using Chern-Simons Topology Euclidean Geometric in a Lindenbaum-Tarski generated QSAR automating modeling and Artificial Intelligence-Driven Predictive Neural Networks.
Geometric Hashing and ΑΙ-Quantum Deep Learning functional similarities on Remdesivir,...
Ioannis Grigoriadis

Ioannis Grigoriadis

January 14, 2021
Νovel SARS coronavirus 2 (SARS-CoV-2) of the family Coronaviridae starting in China and spreading around the world is an enveloped, positive-sense, single-stranded RNA of the genus betacoronavirus encoding the SARS-COV-2 (2019-NCOV, Coronavirus Disease 2019. Remdesivir drug, or GS-5734 lead compound, first described in 2016 as a potential anti-viral agent for Ebola diseade and has also being researched as a potential therapeutic agent against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the coronavirus that causes coronavirus disease 2019 (COVID-19). Computer-aided drug design (CADD), Structure and Ligand based Drug Repositioning strategies based on parallel docking methodologies have been widely used for both modern drug development and drug repurposing to find effective treatments against this disease. Quantum mechanics, molecular mechanics, molecular dynamics (MD), and combinations have shown superior performance to other drug design approaches providing an unprecedented opportunity in the rational drug development fields and for the developing of innovative drug repositioning methods. We tested 18 phytochemical small molecule libraries and predicted their synergies in COVID-19 (2019- NCOV), to devise therapeutic strategies, repurpose existing ones in order to counteract highly pathogenic SARS-CoV-2 infection. We anticipate that our geometry hashing driven quantum deep learing similarity approaches which is based on separated pairs of short consecutive matching fragments, can be used for the development of anticoronaviral drug combinations in large scale HTS screenings, and to maximize the safety and efficacy of the Remdesivir, Colchicine and Ursolic acid drugs already known to induce synergy with potential therapeutic value or drug repositioning to COVID-19 patients.
Liver and kidney function in patients with Covid-19 treated with remdesivir
Sylvia van Laar
M De Boer

Sylvia van Laar

and 4 more

January 14, 2021
For the treatment of Covid-19 patients with remdesivir, poor renal- and liver function were both exclusion criteria in randomized clinical trials (RCTs) and contra-indication for treatment. Also, nephrotoxicity and hepatotoxicity are reported as adverse events. We retrospectively reviewed renal- and liver functions of covid-19 patients who received remdesivir in the 15 days after treatment initiation. Approximately 20% of the patient population met RCT exclusion criteria. In total, 11% of the patients had a decrease in estimated glomerular filtration rate larger than 10 ml/min/1.73m2. Also, 25% and 35% had increased alanine transaminase and aspartate transaminase levels, respectively. However, serious adverse events were limited. Therefore, contra-indications based on kidney- and liver function should not be absolute for remdesivir treatment in patients with Covid-19 if these functions are monitored regularly.
Rare case of intra-oral palatal (soft palate) fibro-lipoma
Manit Mandal
Ajay Panchal

Manit Mandal

and 4 more

January 14, 2021
Background: Case study of 30 years male having suspending mass found over upper surface of soft palate hanging in nasopharynx. Methods: After evaluation, patient underwent combined approach (Trans-oral + Endoscopic) excision. Results: Histopathological examination concluded possibility of intra-oral lipoma. Conclusion: Palatal mass (lipoma) requires surgical excision post complete evaluation.
Migratory fish bone in the pharynx, a report of 2 cases
Shuyi Xu
Xiaomin Li

Shuyi Xu

and 6 more

January 14, 2021
Fish bones have a risk of damaging the mucosa when lodged in the pharynx. Fish bones migrated into surrounding tissues is relatively unusual. We present 2 cases of patients who ingested fish bone, which migrated into retropharyngeal space and hypopharynx. All fish bones were removed without complications.
Cytokine induced modulation of ACE2 and TMPRSS2 expression in primary human nasal epi...
Mahnaz Ramezanpour
Harrison Bolt

Mahnaz Ramezanpour

and 6 more

January 14, 2021
Viral entry of severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) via the spike protein enables endocytosis into host cells using the ACE2 receptor and TMPRSS2. The frequent upper respiratory tract symptoms of COVID-19 and the localization of the virus to the nasopharynx, the most common site of swabbing, indicate that the sinonasal mucosa may play an important role in SARS-CoV2 infection and viral replication. This paper investigates the presence of ACE2 Receptor and TMPRESS2 expression in the primary human nasal epithelial cells (HNECs) from Control, CRSsNP, and CRSwNP and maps the expression changes when exposed to Th1, Th2, Th17 associated cytokines. We found that ACE2 and TMPRSS2 expression is higher in control HNECs than CRSwNP HNECs, and that both ACE2 and TMPRSS2 are downregulated further by Th2 cytokines in CRSwNP HNECs. This indicates an immune dysregulated state of CRSwNP mucosa, which normally contributes to a chronic inflammatory state, might support an altered susceptibility to SARS-CoV2 infection and transmission.
Local impedance and ultra-high density 3-dimensional mapping results in improved abla...
Karan Saraf
Nicholas Black

Karan Saraf

and 4 more

January 14, 2021
Introduction Multiple contact-based ablation technologies have been developed to allow real-time judgement of lesion effectiveness; local impedance (LI) guided ablation and the role of ultra-high density (UHD) mapping have not yet been evaluated for cavotricuspid isthmus dependent atrial flutter (CTI-AFL). Methods This non-randomised observational study evaluated patients undergoing CTI-AFL ablation using conventional, contact force (CF) and LI guided strategies. Ablation metrics were collected, and in the LI cohort, the use of UHD mapping for breakthrough was evaluated. Results 30 patients were included, 10 in each group. Mean total ablation time was significantly shorter with LI (3.2±1.3min) vs conventional (5.6±2.7min) and CF (5.7±2.0min, p=0.0042). Time from start of ablation to CTI block was numerically shorter with LI (14.2±8.0min) vs conventional and CF (19.7±14.1 and 22.5±19.1min, p=0.4408). There were no differences in the number of lesions required to achieve block, procedural success, complication rates or recurrence. 15/30 patients did not achieve block following first-pass ablation. UHD mapping rapidly identified breakthrough in the 5 LI patients, including epicardial-endocardial breakthrough (EEB) away from the line. Conclusion The use of LI for real-time assessment of lesion formation resulted in significantly less ablation requirement. UHD mapping rapidly identified breakthrough, including EEB, which would likely have been difficult to identify otherwise and possibly require extensive ablation, contributing towards shortening of time to CTI block with LI.
4- hydroxy-3,5-di-tret-butyl cinnamic acid restores the activity of the hippocampal m...
Dmitry Pozdnyakov

Dmitry Pozdnyakov

January 13, 2021
Background and Purpose: Ischemic stroke remains one of the leading causes of death in the population. In addition, mitochondrial dysfunction is an essential part of the pathogenesis of cerebral ischemia and is a promising pharmacotherapeutic target. Experimental Approach: the work was performed on male Wistar rats, which were simulated cerebral ischemia by irreversible occlusion of the middle cerebral artery. 4-hydroxy-3,5-di-tret-butyl cinnamic acid (25 mg/kg, 50 mg/kg and 100 mg/kg) was injected intraperitoneally for 3 days after ischemia (daily). On the 4th day of the experiment, the changes of rat’s cognitive functions in the Morris water maze test, cellular respiration processes, the activity of the mitochondrial respiratory chain complexes and citrate synthase activity, the intensity of oxidative stress and apoptosis reactions were assessed. Key Results: it was found that the administration of 4-hydroxy-3,5-di-tret-butyl cinnamic acid at doses of 25 mg/kg and 50 mg/kg practically equivalently promotes the restoration of aerobic metabolism reactions and the activity of the mitochondrial respiratory chain complexes, decrease of the intensity of oxidative stress reactions and apoptosis, as well as an increase in the activity of citrate synthase. As a result, the restoration of mitochondrial function in the hippocampal cells contributed to the restoration of the animal’s spatial memory. Conclusion and Implications: a study showed that 4-hydroxy-3,5-di-tret-butyl cinnamic acid at doses of 25 mg/kg and 50 mg/kg has a neuroprotective effect on hippocampal neurons under conditions of permanent occlusion of the middle cerebral artery, realized by restoration of mitochondrial function.
Impact of Sinus Rhythm Maintenance on Major Adverse Cardiac and Cerebrovascular Event...
Keisuke Usuda
Takeshi Kato

Keisuke Usuda

and 34 more

January 13, 2021
Introduction: The impact of catheter ablation for atrial fibrillation (AF) on cardiovascular events and mortality is controversial. We investigated the impact of sinus rhythm maintenance on major adverse cardiac and cerebrovascular events after AF ablation from a Japanese multicenter cohort of AF ablation. Methods and Results: We investigated 2737 consecutive patients (25.6% female, mean age 63.4 ± 10.3 years) who underwent a first catheter ablation for AF from the Atrial Fibrillation registry to Follow the long-teRm Outcomes and use of aNTIcoagulants aftER Ablation (AF Frontier Ablation Registry). The primary endpoint was a composite of stroke, transient ischemic attack, cardiovascular events, and all-cause death. During a mean follow-up of 25.2 months, 2070 (75.6%) patients were free from AF after catheter ablation, and the primary composite endpoint occurred in 122 (4.5%) patients. The AF nonrecurrence group had a significantly lower incidence of the primary endpoint (1.7 per 100 person-years) compared with the AF recurrence group (3.2 per 100 person-years; P = 0.001). The multivariate analysis revealed that freedom from AF (hazard ratio 0.57; 95% confidence interval 0.39–0.83; P = 0.003) was independently associated with the incidence of the composite event.¬¬ Conclusion: In the multicenter cohort of AF ablation, sinus rhythm maintenance after catheter ablation was independently associated with lower rates of major adverse cardiac and cerebrovascular events.
Successful treatment of acute promyelocytic leukemia in a patient under hemodialysis...
akiko hashimoto
yasuhiro tanaka

akiko hashimoto

and 2 more

January 13, 2021
A man with chronic kidney disease (CKD) under hemodialysis was diagnosed with acute promyelocytic leukemia (APL). He received arsenic trioxide as a single agent and achieved complete molecular remission without severe adverse events. Arsenic trioxide (ATO) can be used safely and effectively for APL with CKD
Dynamics adsorption of the enhanced CH4 recovery by CO2 injection
Min Gu
Shuo Duan

Min Gu

and 2 more

January 13, 2021
The dynamic adsorption isotherms of CO2-EGR were measured by using a Intelligent Gravimetric Analysis system.In the beginning stage of CO2 injection, all the injected CO2 enters into the adsorbent and the mole fraction of CH4 (yCH4) keeps 1.0. The CH4 recovery factor (RCH4) increases. The during of this stage (tcd) depends on the selectivity of CO2 over CH4 ( SCO2/CH4). A adsorbent with large SCO2/CH4 has long tCD. When SCO2/CH4 is greater than 1.0, CO2 reduces the fraction of CH4 in the adsorbed phase (xCH4) and more CH4 is driven out. In the second stage,the injected CO2 competes with CH4 for adsorption. The cumulative RCH4 of this stage is much larger than that of the initial stage. However, yCH4 decrease sharply. pCH4 in the whole CO2 injection is always larger than that before CO2 injection, suggesting CH4 desorption results from the displacement by CO2 rather than from pressure depletion.
LEFT ATRIAL APPENDAGE MANAGEMENT: A SURGICAL PERSPECTIVE
Fabrizio Rosati
Gijs de Maat

Fabrizio Rosati

and 3 more

January 13, 2021
Atrial fibrillation (AF) is the most common atrial arrhythmia but it is not a benign disease. AF is an important risk factor for thromboembolic events, causing significant morbidity and mortality. The left atrial appendage (LAA) plays an important role in thrombus formation but the ideal way to manage the LAA is still debated. The increasing popularity of surgical epicardial ablation and hybrid endo-epicardial ablation approaches, especially in patients with a more advanced diseased substrate, has raised the interest in epicardial LAA management. Minimally invasive treatment options for the LAA offer a unique opportunity to close the LAA with a clip device. This review highlights morphologic, electrophysiologic and surgical aspects of the left atrial appendage with regard to atrial fibrillation surgery, and aims to illustrate the different surgical management strategies.
Case of Resistance to Thyroid hormones (RTH) with relatively rare mutation in Thyroid...
Hind Ahmed
Khalid Khamis

Hind Ahmed

and 2 more

January 13, 2021
This is an article that share clinical manifestation and diagnosis of patient with THR mutation, who found to have very rare mutation in THR-beta.
Impianto di depurazione delle acque reflue: progettazione di impianti con bioreattori...
FABIO PASTORE

FABIO PASTORE

January 13, 2021
In considerazione della sempre minore disponibilità di acque di buona qualità, un tema, oggetto di attenzione sia scientifica che legislativa, è la possibilità di riutilizzo delle acque reflue. Obiettivo del riutilizzo è la limitazione del prelievo delle acque superficiali e sotterranee, e la riduzione degli scarichi sui corpi idrici recettori. Il trattamento biologico rappresenta la fase più importante del ciclo depurativo delle acque reflue. I naturali processi biologici sono sfruttati all’interno degli impianti a fanghi attivi (CAS). Gli impianti di depurazione MBR si sono affermati nel panorama nazionale e internazionale come una consolidata alternativa ai convenzionali impianti a fanghi attivi, in particolare laddove sia necessario contenere l’ingombro planimetrico e/o garantire un effluente di qualità elevata. L’attività di tirocinio, svolta presso il Laboratorio di Ingegneria Sanitaria Ambientale (SEED) dell’Università degli Studi di Salerno, è stata finalizzata in una prima fase allo studio approfondito e al confronto tra le tipologie di trattamento convenzionali e innovative e, nella seconda fase, alla progettazione di modelli virtuali tridimensionali che rappresentano impianti innovativi, basati sull’utilizzo della tecnologia MBR.
Chylopericardium associated with constrictive pericarditis assessed by multimodality...
Emmanuel Androulakis
Konstantinos Bratis

Emmanuel Androulakis

and 3 more

January 13, 2021
Abstract An 80-year-old male patient developed exertional dyspnea and bilateral peripheral oedema. Investigations including an echocardiogram, cardiac computed tomography and cardiac magnetic resonance suggested calcific pericardial thickening encapsulating the heart with associated constriction. This is an interesting case as constriction was associated with a large chylopericardium of unknown cause
Effects of landscape context on different groups of cavity-nesting bees, wasps and th...
Károly Lajos
Imre Demeter

Károly Lajos

and 4 more

January 13, 2021
In this study our aim was to assess the diversity and distribution of cavity-nesting solitary bees, wasps and the spider-hunting wasps' prey with regards to the influence of landscape context in a study area with relatively low human disturbance. The study took place between May and August 2018 at eight study sites in the hilly-mountainous central part of Romania, where the majority of the landscape is used for extensive farming or forestry. During the processing of the trap nest material, we recorded several parameters regarding the nests of different hymenopteran groups, the spider prey found inside these nests, and also tested the influence of the landscape structure surrounding the sites on both hymenopteran groups and spider prey. The majority of nests was built by the solitary wasp group of Trypoxylon, followed by Dipogon and Eumeninae. Solitary bees were much rarer, with Hylaeus being most common group. The groups showed partially differing size preferences concerning the diameter of the occupied reed stalks. In the nests of Trypoxylon we predominantly found spider prey from the family of Araneidae, followed by representatives from the families of Linyphiidae and Theridiidae. In contrast to Trypoxylon, the wasp group Dipogon preferred spider prey from the family of Thomisidae. Concerning the hymenopteran groups, significant effects of landscape structure were found on the number of both nests and brood cells of Eumeninae and on the number of brood cells of Hylaeus, Osmia and Trypoxylon. We also found that the diversity of Trypoxylon spider prey was significantly positively affected by an increasing proportion of grassland and negatively by an increasing proportion of woodland. Altogether, our study presents several new aspects concerning the diversity and distribution of solitary bees, wasps and the spider-hunting wasps' prey and also the effects of landscape context on these groups.
On linking mechanism to invasive species impact
Marc Cadotte

Marc Cadotte

January 13, 2021
Species invasion represents one of the major drivers of biodiversity change globally, yet there is widespread scientific and popular confusion and controversy about the nature of non-indigenous species (NIS) impact. This confusion stems from differing notions and understanding of what constitutes invasive species ‘impact’ and the scales at which it should be assessed. I argue that the proximate mechanisms determining invasive species impact happen at smaller scales where species interact, and by understanding these mechanisms, we can scale up to a broader understanding of how invasive species impact biodiversity. The mechanisms of NIS impact on potential competitors can be classified into four scenarios: 1) minimal impact from NIS inhabiting unique niche space; 2) neutral impact spread across the community and proportional to NIS abundance; 3) targeted impact on a small number of competitors with overlapping niches; and 4) pervasive impact that is disproportionate to NIS abundance and ostensibly caused by ecosystem modification that filters out other species. I develop a statistical test to distinguish these four mechanisms based on community rank-abundance curves. Using an example dataset from plant communities invaded by the dominant invasive vine, Vincetoxicum rossicum, I show that in long-term plots that had high native plant diversity and where V. rossicum increased, impact resulted in either targeted extirpations (scenario 3) or widespread biodiversity loss (scenario 4). Regardless of whether NIS impact is neutral, targeted or pervasive, the net outcome will be the homogenization of ecosystems and reduced biodiversity at larger scales, perhaps reducing ecosystem resilience.
Commentary: Predictors of Postoperative Adverse Events after Cone Reconstruction for...
Evan Rotar
Irving Kron

Evan Rotar

and 1 more

January 13, 2021
Prediction scores and metrics are being increasingly utilized throughout the fields of cardiothoracic and congenital cardiac surgery to identify areas for perioperative optimization or guide therapeutic intent. Here, we review a novel submission by Yang and colleagues to the Journal of Cardiac Surgery identifying preoperative factors which predict adverse postoperative outcomes from cone reconstruction for Ebstein's anomaly.
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