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Branch pulmonary artery Doppler in the assessment of atrial restriction after the hyb...
Hannah Bellsham-Revell
Eva Kapravelou

Hannah Bellsham-Revell

and 4 more

January 17, 2021
Introduction: The hybrid procedure (HP) - bilateral pulmonary artery bands+ductal stent - is an alternative palliation for high-risk hypoplastic left heart syndrome (HLHS) patients. Assessment and management of atrial restriction here is debated and we sought to identify useful echocardiographic parameters. Methods: Patients undergoing HP for HLHS were identified. Echocardiograms at birth, immediately after HP and pre-and post-atrial intervention were reviewed as well as time-matched echocardiograms in HP patients not requiring atrial intervention. Atrial septal parameters and systolic (Svel), diastolic (Dvel) and mean velocities were recorded on both bands and systolic to diastolic velocity ratio (Svel:Dvel), pulsatility index (PI) and velocity time integral (VTI) calculated. Results: Fifteen HP were compared to 5 controls. Age effect was not significant. There was a significant rise in peak Svel and changes in Dvel, Svel:Dvel and PI over time (<0.05). Although the pattern of change similar, the fall in Dvel and rise in Svel:Dvel and PI was more significant on the left. Compared to controls, transatrial gradient and VTI were significantly increased initially post-hybrid (median 0.4m/s vs 0.7m/s p=0.04; 29.1cm vs 64.6cm p=0.018) but not significantly different prior to septostomy when the only significant differences were seen with all left band parameters. Conclusions: After HP the transatrial gradient alone cannot be used. Significant changes in band Doppler parameters were not apparent in the control group but were principally seen in the left band with reduction in Dvel and increase in Svel:Dvel and PI in those undergoing an atrial intervention.
What Matters Most To Women Undergoing Hysterectomy?
JOSE DE LOS RIOS
CLAUDIA LOPEZ

JOSE DE LOS RIOS

and 5 more

January 16, 2021
ABSTRACT Study objective: to gain an understanding of patient preferences regarding choice of surgical approach to hysterectomy. Design: Cross-sectional, analytical study. Setting: Tertiary hospital, referral center for gynecologic surgery in Medellin, Colombia Patients: A total of 300 women, 150 who were scheduled for hysterectomy and 150 women who were not undergoing any surgical procedure. Interventions: A questionnaire listing advantages of laparoscopic, vaginal, and abdominal hysterectomy was designed and applied to all participating women, who were then asked to rank in order of relevance the surveyed items. Answers and demographic variables were collected. Measurements and Main results: Average scores were calculated for each of the listed variables, and the difference of medians between groups (women scheduled to undergo hysterectomy and women who were not undergoing surgery) was analyzed. Difference of medians was also analyzed by grouping participants based on educational level. Participating women ranked as most important: safety, pain, duration of sick leave, scars, operative time, duration of surgical training, and cost. Altogether, women preferred advantages offered by laparoscopic hysterectomy over those provided by vaginal or abdominal approaches. Conclusion: Patient preferences should be taken into account upon deciding the surgical approach to hysterectomy, as they may differ from those of the physician. Key Words: Hysterectomy, preferences, approach
Paternal hepatitis B virus infection with different clinical courses between siblings
Yoshiaki Sasaki
Hiroki Kajino

Yoshiaki Sasaki

and 1 more

January 16, 2021
No countermeasures have been established against horizontal infection in non-vaccinated children. We reported about siblings with different clinical courses of HBV paternal infection. To eradicate HBV, we should encourage HBV vaccination of all children and HBV infection screening of fathers and other family members.
A New Hemodynamic Index To Predict Late Right Failure In Patients Implanted With Last...
Andrea Montalto
Cristiano Amarelli

Andrea Montalto

and 6 more

January 16, 2021
Background. Right ventricular failure (RVF) is a severe event that increases perioperative mortality after Left Ventricle Assist Device (LVAD) implantation. RV function is particularly affected by the LVAD speed by changing RV preload and afterload as well as the position of the interventricular septum. However, there are no studies focusing on the relationship between pump speed optimization and risk factors for development of lateRVF. Methods. Between 2015 and 2019,50 consecutive patients received LVAD implantation at San Camillo Hospital in Rome. Of these, 38 who underwent pump speed optimization were included. Post optimization hemodynamic data were collected. We assessed: a new Hemodynamic Index (HI), calculated as follows HI=MAP x PCWP/CVP x RPM set/RPM max; risk factors for late RVF, which was defined as the requirement for 7 days or more of inotropic support. Results 10 patients had late RVF after LVAD implantation. 5 patients required diuretic therapy and speed optimization. In 3 patients inotropic support with adrenaline 0.05 g/kg/min was started. 2 patients required prolonged continuous veno-venous hemofiltration and high dosage inotropic support. Multivariate analysis revealed that a low HI (odds ratio 11.5, 95 % confidence interval,1.85-65.5,p[.003] was an independent risk factor for late RVF after LVAD implantation. Conclusion A low HI, according to our study, is a significant risk factor for the development of RVF after LVAD implantation. We suggest adopting this index during the follow-up to stratify the different hemodynamic profiles and modify the therapeutic strategies according to the different HI levels obtained for every single patient.
Modified mini-maze via left thoracic cavity under VATS for paroxysmal atrial fibrilla...
Fan He
Bijun Xu

Fan He

and 4 more

January 16, 2021
Objectives: We sought to determine the technical feasibility of surgical bipolar radiofrequency ablation (endoscopic maze procedure) through the left chest cavity in patients with an interrupted inferior vena cava (IVC). Methods and Results: A 57-year-old female with paroxysmal atrial fibrillation (AF) and an interrupted IVC was referred to our hospital for radiofrequency ablation. Transseptal puncture and left atrium (LA) ablation failed through a standard IVC approach via the femoral vein due to intrahepatic interruption of IVC. We performed a modified surgical bipolar radiofrequency ablation (RF) on the beating heart through 3 ports in the left chest wall. Pulmonary vein isolation and ablation of the left atrium were achieved by bipolar radiofrequency ablation. Ganglionic plexus ablation was completed using the ablation pen. The left atrial appendage was excluded. No complications occurred during or after the procedure. The patient was discharged with sinus rhythm 3 days later after the procedure. She was taking amiodarone (100mg bid) within 6 months after the procedure, and had no recurrence of AF. Conclusions: We successfully performed a modified mini-maze procedure in a patient with paroxysmal AF and IVC interruption through the left thoracic cavity under video-assisted thoracoscopic surgery (VATS). We can successfully complete pulmonary vein (PV) isolation, left atrium box isolation, cardiac ganglia ablation, Marshall ligament ablation, and coronary sinus epicardium ablation using this technique.
Comparison of alternate preparative techniques on wall thickness in coronary artery b...
Gianni Angelini
Tom Johnson

Gianni Angelini

and 11 more

January 16, 2021
Background: The success of coronary artery bypass grafting surgery (CABG) is dependent on long-term graft patency, which is negatively related to early wall thickening. Avoiding high-pressure distension testing for leaks and preserving the surrounding pedicle of fat and adventitia during vein harvesting may reduce wall thickening. Methods: A single-centre, factorial randomised controlled trial was carried out to compare the impact of testing for leaks under high versus low pressure and harvesting the vein with versus without the pedicle in patients undergoing CABG. The primary outcomes were graft wall thickness, as indicator of medial-intimal hyperplasia, and lumen diameter assessed using intravascular ultrasound after 12 months. Results: 96 eligible participants were recruited. With conventional harvest, low-pressure testing tended to yield a thinner vessel wall compared to high-pressure (mean difference MD (low minus high) -0.059mm, 95%CI -0.12, +0.0039, p=0.066). With high pressure testing, veins harvested with the pedicle fat tended to have a thinner vessel wall than those harvested conventionally (MD (pedicle minus conventional) -0.057mm, 95%CI -0.12, +0.0037, p=0.066, test for interaction p=0.07). Lumen diameter was similar across groups (harvest comparison p=0.81; pressure comparison p=0.24). Low pressure testing was associated with fewer hospital admissions in the 12 months following surgery (p=0.0008). Harvesting the vein with the pedicle fat was associated with more complications during the index admission (p=0.0041). Conclusions: Conventional saphenous vein graft preparation with low pressure distension and harvesting the vein with a surrounding pedicle yielded similar graft wall thickness after 12 months, but low pressure was associated with fewer adverse events.
Innominate artery dissection during cerebral perfusion. The exception that proves the...
Antonio Piperata
Tomaso Bottio

Antonio Piperata

and 3 more

January 16, 2021
Bilateral antegrade selective cerebral perfusion has the undisputed advantage of being more physiological and theoretically ensuring complete perfusion of the whole brain. However, it requires longer execution times and manipulation of the epiaortic vessels. On the other hand, unilateral selective cerebral perfusion (u-ASCP) avoids the vessels manipulation, placement of catheters into the ostia of the great vessels which clutters the operative field and incurs both atherosclerotic and air embolism risk. Neverthless, an ongoing debate about which technique yields the best clinical outcomes is still open.
If it ain't broke don't fix it
Berhane Worku
Meghann Fitzgerald

Berhane Worku

and 1 more

January 16, 2021
If it an’t broke, don’t fix itBerhane Worku MD1, Meghann M Fitzgerald21: Department of Cardiothoracic Surgery, Weill Cornell Medical College2. Department of Anesthesiology, Weill Cornell Medical CollegeAntifibrinolytics and TEGCorresponding Author:Berhane WorkuDepartment of Cardiothoracic SurgeryWeill Cornell Medical College525 East 68th Street M-404New York, NY 10065Despite evidence of associated morbidity and mortality, blood products are administered to over half of cardiac surgical patients, accounting for approximately 20% of their worldwide use1,2. These statistics attest to the ubiquitous and refractory nature of bleeding after cardiac surgery. In an attempt to curb the excessive use of blood products after cardiac surgery viscoelastic testing in the form of thromboelastography (TEG) and rotational thromboelastometry (ROTEM) have been increasingly utilized. Rapid intraoperative assessment allows for targeted correction of coagulopathy due to residual heparinization, coagulation factor deficiency, hypofibrinogenemia, and platelet dysfunction. Hyperfibrinolysis can also be assessed, although management is rarely altered as the routine administration of lysine analog antifibrinolytics has been given a class I recommendation by the Society of Thoracic Surgeons and the Society of Cardiovascular Anesthesiologists and has become the standard practice at most cardiac surgical centers.Cardiopulmonary bypass is known to result in transient t-PA and subsequent d-dimer level elevations (a marker of hyperfibrinolysis)3,4. The efficacy of the lysine analog antifibrinolytics, tranexamic acid andε-aminocaproic acid, have been extensively studied in this setting. D-dimer levels are significantly blunted by antifibrinolytics, and an abundance of literature demonstrates reductions in chest tube bleeding, blood product use, and reoperation for bleeding with the use of these agents4-6. A similar amount of evidence points to their safety, with no increase in thrombotic complications, including stroke, myocardial infarction, graft closure, or mortality seen5-7. A higher risk of seizures is noted with tranexamic acid, although this appears to be dose dependent and nonexistent with ε-aminocaproic acid2. If the ultimate goal is to reduce bleeding and blood product usage, it would seem that antifibrinolytics offer one way to do this safely.In the current manuscript, Sussman et. al. retrospectively analyze 78 cardiac surgical patients who had an intraoperative TEG performed with the goal of describing the distribution of fibrinolytic phenotypes in this population8. Forty five percent demonstrated physiologic fibrinolysis, 32% hypo fibrinolysis, and 23% hyperfibrinolysis (LY30 <0.8%, 0.8-3%, >3%). Forty seven percent received antifibrinolytic agents. Outcomes including “morbidity” and time with chest tube were higher in those who received antifibrinolytics. This is a perhaps the first study of its kind to describe the prevalence of hyperfibrinolysis in cardiac surgical patients as measured by point of care testing. It is also a very relevant study in an era in which the benefits of targeted therapy for coagulopathy are increasingly recognized.The current data suggests that half of patients undergoing cardiac surgery demonstrate physiologic fibrinolysis and a third demonstratehypo fibrinolysis (a theoretically pro thrombotic state)8. The worse outcomes seen in patients receiving antifibrinolytics suggests that their administration in the setting of a potentially prothrombotic state was to blame. However, several limitations merit mention. It appears that TEG is not routinely performed on all patients. The population under study may therefore reflect one undergoing more extensive surgery with more coagulopathy in whom TEG is more likely to be performed. Since the actual timing of the TEG is not detailed, the true baseline fibrinolytic phenotype of patients treated with antifibrinolytics is not clear as the TEG results may have been obtained after the initiation of antifibrinolytics. Furthermore, while surgical procedures performed weren’t delineated, patients receiving antifibrinolytics more frequently had “valve disease” and “heart failure” and underwent on-pump surgery. Patients receiving antifibrinolytic therapy were therefore sicker and likely underwent more extensive on-pump valve surgery, while patients who did not receive antifibrinolytics were most likely undergoing off-pump coronary bypass surgery. Finally, the increased “morbidity” in patients receiving antifibrinolytics appear to be bleeding related (thrombotic complications were not listed separately). Perhaps additional antifibrinolytics were needed.The authors are to be commended for recognizing a lack of complete understanding of coagulation in the cardiac surgical population and attempting to determine the benefit of targeted antifibrinolytic therapy. Any time a practice is performed indiscriminately, there is room for improvement. However, before we contemplate altering an evidence-based practice that reduces bleeding, we need to demonstrate a benefit for such a change. Not all bleeding is purely surgical or purely medical; there is overlap. Few areas of medicine highlight how much art prevails over our current scientific understanding. Too many times since the introduction of point-of-care testing, the surgeon and anesthesiologist battle over the merits of administering blood products to a clinically bleeding patient with a normal coagulation profile. Targeted correction of coagulopathy is conceptually attractive, but the reality is not as clearly defined. Reductions in bleeding seen with antifibrinolytics occur both in on-pump and off-pump surgery which should be enough proof to continue its application until better evidence and understanding emerges6. Certainly, there is more work to be done, but with regard to antifibrinolytics it seems fitting to recognize: If it ain’t broke, don’t fix it.REFERENCESAbdelmotieleb M, Agarwal S. Viscoelastic testing in cardiac surgery. Transfusion 2020;60:52-60Harvey R, Salehi A. Con: Antifibrinolytics should not be used routinely in low-risk cardiac surgery. J Cardiothorac Vasc Anesth 2016;30:248-251Gielen C, Brand A, van Heerde W, Stijnen T, Klautz R, Eikenboom J. Hemostatic alterations during coronary artery bypass grafting. Thromb Res 2016;140:140-146Slaughter T, Faghih F, Greenberg C, Leslie J, Sladen R. The effects of ε-aminocaproic acid on fibrinolysis and thrombin generation during cardiac surgery. Anesth Analg 1997;85:1221-6Myles PS, Smith JA, Forbes A, Silbert B, Jayarajah M, Painter T, Cooper J, Marasco S, McNeil J, Bussieres JS, McGuinness S, Byrne K, Chan MTV, Landoni G, Wallace S. Tranexamic acid in patients undergoing coronary-artery surgery. N Engl J Med 2017;376:136-48Zhang Y, Bai Y, Chen M, Zhou Y, Yu X, Zhou H, Chen G. The safety and efficiency of intravenous administration of tranexamic acid in coronary artery bypass grafting (CABG): a meta-analysis of 28 randomized controlled trials. BMC Anesthesiol 2019;19:104Kasrki J, Djaiani G, Carroll J, Iwanochko M, Seneviratne P, Liu P, Kucharczyk W, Fedorko L, David T, Cheng D. Tranexamic acid and early saphenous vein graft patency in conventional coronary artery bypass graft surgery: A prospective randomized controlled clinical trial. J Thorac Cardiovasc Surg 2005;130:309-14Sussman MS, Urrechaga EM, Cioci AC, Iyengar RS, Herrington TJ, Ryon EL, Namias N, Galbut DL, Salerno TA, Proctor KG. Do all cardiac surgery patients benefit from antifibrinolytic therapy? J Card Surg in press
Vasa praevia with meandering foetal vessels despite placental and umbilical cord inse...
Tatsuro Horiuchi
Hiroshi Sato

Tatsuro Horiuchi

and 5 more

January 16, 2021
A 38‐year‐old patient with gravida 2, para 1 was referred to our hospital for perinatal management. At 37 weeks gestation, we diagnosed vasa praevia with meandering foetal vessels. Emergent caesarean section was performed. Obstetricians should be familiar with vasa praevia with meandering foetal vessels despite its rare occurrence.
Recurrent Coronavirus Diseases 19 (COVID-19): A Different Presentation from the First...
Saeed Shoar
Siamak Khavandi

Saeed Shoar

and 3 more

January 16, 2021
A 31-year-old male Caucasian patient developed reinfection with SARS-CoV-2, 2 ½ months after an initial episode of ICU admission for respiratory support due to COVID-19. The second episode was in the form of malaise, aphthous gingival ulcer, and desquamating palmar lesion.
DOES THE INTRATYMPANIC APPLICATION OF MESNA PREVENT THE CHOLESTEATOMA? AN EXPERIMENTA...
BİLAL SİZER
Aylin Gül

BİLAL SİZER

and 2 more

January 16, 2021
Purpose Studying the effect of Mesna on middle ear otitis media and cholesteatoma induced by propylene glycol on an experimental animal model. Methods The study was designed to consist of sixteen Wistar albino rats, their right ears being the control group and left ears being the experiment group. %50 propylene glycol, gentamicinsulfate and physiologic salt water were applied to the right ear and %50 propylene glycol, gentamicinsulfate and %20 Mesna were administered to the left ear through intratympanic injections on days 1, 3, 8, 15 and 21. The rats were sacrificed 45 days after the first injection and underwent histopathological examination. Results It was seen that cholesteatoma and fibrosis were less common in the experiment group in microscopic evaluation. A statistically significant decrease was observed when the average and maximum thicknesses of the tympanic membranes and the minimum thicknesses of the tympanic bulla of the control group and the experiment group were compared. (p< 0.05) Conclusion In the experimental cholesteatoma model created in rats, no statistical significance was observed, indicating that Mesna, which was applied intratympanically, completely prevented the formation of cholesteatoma. However, it was found that the prevalence of cholesteatoma formation was microscopically less in the experimental group.
Interferon-beta changes the expression of IL10, IL23A and FOXP3 on Multiple Sclerosis...
Hazal Gezmis
Tansu Doran

Hazal Gezmis

and 5 more

January 16, 2021
Aim of the Study: Multiple sclerosis (MS) is an autoimmune disorder causing demyelination in axons. Available therapies target different molecules, but not all have therapeutic effects on disease progression, and this effect can only be seen after a long-time administration. Interferon beta (IFN-β), an MS therapy for many years, slows down the disease progression and reduces disease symptoms by targeting T cells. Yet, a considerable portion of the patient has experienced no therapeutic response to IFN-β. It is necessary to determine disease-specific biomarkers which allow early diagnosis or treatment of MS. Here, it was aimed to determine the effects of interleukin 10 (IL10) and 23 (IL23A) as well as forkhead box P3 (FOXP3) genes on MS after IFN-β therapy. Materials & Methods: Peripheral blood mononuclear cells (PBMCs) were extracted to isolate CD4+ and CD25+ T cells. Cytotoxicity assays were performed on each cell type for determining optimum drug concentration. Then, cells were cultured and determined drug concentration was administered to the cells to measure gene expressions with RT-PCR. Results: It was found that the cytotoxic effect of IFN-β was more efficient as the exposure time was expanded regardless of drug concentration. Moreover, CD25+ T lymphocytes were more resistant to IFN-β. IL23A was down-regulated, whereas FOXP3 was up-regulated at 48h in CD4+ T cells. For CD25+ T cells, the graded increase of FOXP3 was obtained while IL10 expression was gradually decreased throughout the drug intake, significantly. Conclusion: Although considerable change in expression was obtained, the long-term IFN-β effect on both genes and cells should be determined by follow-up at least a year. Keywords: MS, IFN-β, IL23A, FOXP3, IL10, T cells
Detection of SARS-CoV-2 Specific Memory B cells to Delineate Long-Term COVID-19 Immun...
Constantin Thieme
Mohamed Abou-el-Enein

Constantin Thieme

and 15 more

January 15, 2021
Background: The ongoing COVID-19 pandemic, caused by the novel coronavirus SARS-CoV-2, represents a serious worldwide health concern. A deeper understanding of the immune response to SARS-CoV-2 will be required to refine vaccine development and efficacy as well as to evaluate long-term immunity in convalescent patients. With this in mind, we investigated the formation of SARS-CoV-2 specific BMEMORY cells from patient blood samples. Methods: A standard flow cytometry-based protocol for the detection of SARS-CoV-2 specific B cells was applied using fluorochrome-coupled SARS-CoV-2 spike (S) full-length protein. Cohorts of 26 central European convalescent mild/moderate COVID-19 patients and 14 healthy donors were assessed for the levels of SARS-CoV-2 S- specific BMEMORY cells. Results: Overall B cell composition was not affected by SARS-CoV-2 infection in convalescent patients. Our analysis of SARS-CoV-2 specific BMEMORY cells in samples collected at different time points revealed that S-protein specific B cells remain in peripheral blood at least up to 6 months after COVID-19 diagnosis. Conclusions: Detection of SARS-CoV-2 specific BMEMORY cells may improve our understanding of the long-term adaptive immunity in response to SARS-CoV-2, allowing for an improved public health response and vaccine development during the COVID-19 pandemic. Further validation of the study in larger and more diverse populations and a more extended observation period will be required.
Allergen immunotherapy: the growing role of observational and randomised trial “real-...
Giovanni Paoletti
Danilo Di Bona

Giovanni Paoletti

and 13 more

January 15, 2021
Although there is a considerable body of knowledge about allergen immunotherapy (AIT), there is a lack of data on the reliability of real-world evidence (RWE) in AIT and consequently, a lack of information on how AIT effectively works in real life. To address the current unmet need for an appraisal of the quality of RWE in AIT, the European Academy of Allergy and Clinical Immunology Methodology Committee recently initiated a systematic review of observational studies of AIT, which will use the RELEVANT tool and the Grading of Recommendations Assessment, Development and Evaluation approach (GRADE) to rate the quality of the evidence base as a whole. The next step will be to develop a broadly applicable, pragmatic “real-world” database using systematic data collection. Based on the current RWE base, and perspectives and recommendations of authorities and scientific societies, a hierarchy of RWE in AIT is proposed, which places pragmatic trials and registry data at the positions of highest level of evidence. There is a need to establish more AIT registries that collect data in a cohesive way, using standardised protocols. This will provide an essential source of real-world data that can be easily shared, promoting evidence-based research and quality improvement in study design and clinical decision-making.
Surgical repair of a giant congenital left atrial aneurysm presenting with respirator...
Alwaleed Al-Dairy
hazem aljasem

Alwaleed Al-Dairy

and 2 more

January 15, 2021
Congenital left atrial aneurysm is a very rare congenital cardiac anomaly, and very few cases have been reported with neonatal presentation. Despite the congenital origin of this condition, it may remain asymptomatic and patients may not present until their third decade of life. Even in asymptomatic cases, prompt surgical intervention is indicated for the prevention of fatal thromboembolic events such as stroke. In neonates and infants presenting early in life, surgical intervention is urgent to relieve respiratory distress symptoms. Herein, we introduce the case of a 3-week-old neonate who presented with severe respiratory distress symptoms requiring prompt intubation and mechanical ventilation. Diagnosis of congenital left atrial aneurysm was established and confirmed by transthoracic echocardiography and computed tomography angiography. The patient underwent surgical resection of the aneurysm using cardiopulmonary bypass and cardiac arrest. The patient was discharged from the hospital after three weeks with normal echocardiography.
Interior and H-∞ feedback stabilization for sabra Shell model of turbulence
Tania Biswas
Sheetal Dharmatti

Tania Biswas

and 1 more

January 15, 2021
Shell models of turbulence are representation of turbulence equations in Fourier domain. Various shell models are studied for their mathematical relevance and the numerical simulations which exhibit at most resemblance with turbulent flows. One of the mathematically well studied shell model of turbulence is called sabra shell model. This work concerns with two important issues related to shell model namely feedback stabilization and robust stabilization. We first address stabilization problem related to sabra shell model of turbulence and prove that the system can be stabilized via finite dimensional controller. Thus only finitely many modes of the shell model would suffice to stabilize the system. Later we study robust stabilization in the presence of the unknown disturbance and corresponding control problem by solving an infinite time horizon max-min control problem. We first prove the $H^ \infty$ stabilization of the associated linearized system and characterize the optimal control in terms of a feedback operator by solving an algebraic riccati equation. Using the same riccati operator we establish asymptotic stability of the nonlinear system.
‘Everything is not everywhere’: time-calibrated phylogeography of the genus Milnesium...
Witold Morek
Bartłomiej Surmacz

Witold Morek

and 3 more

January 15, 2021
There is ample evidence that macroscopic animals form geographic clusters termed as zoogeographic realms (zones), whereas distributions of species of microscopic animals are still poorly understood. The common view has been that micrometazoans, thanks to their putatively excellent dispersal abilities, are subject to the ‘Everything is Everywhere but environment selects’ hypothesis (EiE). One of such groups, <1 mm in length, are limnoterrestrial water bears (Tardigrada), which can additionally enter cryptobiosis that should further enhance their potential for long distance dispersion (e.g. by wind). However, an increasing number of studies, including the most recent phylogeny of a eutardigrade genus Milnesium, seem to question the general applicability of the EiE hypothesis to tardigrade species. Nevertheless, all the Milnesium phylogenies published to date were based on a limited number of populations, which are likely to falsely suggest limited geographic ranges. Thus, in order to comprehensively test the EiE hypothesis, here, we considerably enlarged the Milnesium dataset both taxonomically and geographically, and we analysed it in tandem with climate type and reproductive mode. Additionally, we time-calibrated our phylogeny to align it with major geological events. Our results show that, although cases of long distance dispersal are present, they seem to be rare and mostly ancient. Overall, Milnesium species are restricted to single zoogeographic realms, which suggests that these tardigrades have limited dispersal abilities. Finally, our results also suggest that the breakdown of Gondwana may influenced the evolutionary history of Milnesium. In conclusion, phylogenetic relationships within the genus seem to be determined mainly by paleogeography.
Current Perspectives on Phytomedicines targeting Cancer Stem Cells
Mrunmayee Saraff
Rekha  Gahtori

Mrunmayee Saraff

and 7 more

January 15, 2021
Studies have established the presence of a small subpopulation of cells within tumor cells, known as cancer stem cells (CSCs). These cells have evidently been the reason for metastasis, chemotherapy or radiotherapy resistance and tumor relapses in several types of cancers. CSCs are prone to epithelial-to-mesenchymal transition (EMT), resulting in aggressive tumors. They modulate various pathways of molecular signaling, including Wnt, Hedgehog and Notch, thus increasing the stem-like characteristics. Elevated expression of ATP binding cassette (ABC) transporter efflux pump as well as suppression of apoptosis has also increased anti-cancer drug resistance. Plants are known to possess bioactive compounds that can modulate these key regulators and hence eliminate CSCs. This review aims to report and summarize preclinical studies about the effects of phytocompounds on CSCs of various tumors. Furthermore, clinical trials carried out for some of these phytoconstituents are reported. Thus, selectively targeting CSCs with plant extracts and herbal preparations may be a promising remedial strategy for cancer.
H2 effect in Cr/PNP-catalyzed ethylene tetramerization: a DFT study
FangqianYin
Tingchun Zhu

Fangqian Yin

and 3 more

January 15, 2021
It is well noticed that hydrogen promotes catalyst activity in Cr/PNP-catalyzed ethylene tetramerization, but the mechanism of this boost is unclear. A density functional theory (DFT) study devoted to exploring this effect was conducted, and conformation changes were carefully taken into consideration to build a clear reaction pathway. Three components in the catalytic cycle was examined in detail: the production of 1-hexene from the metallacycloheptane, the production of 1-octene from metallacyclononane, and the formation of active center on the catalyst. The result indicates that the formation of active center on the catalyst becomes more favorable upon imposition of hydrogen, where hydrogen function as a second ligand. This easing effect could be the key factor leading to the outperformed catalyst activity.
PRESSURE AND STRESS ANALYSIS OF LIQUID-FILLED CYLINDRICAL TANK
Kamila Kotrasova
Eva Kormanikova

Kamila Kotrasova

and 2 more

January 15, 2021
During earthquakes, the liquid-filled storage tank generates hydrodynamic pressures, in addition to hydrostatic pressure, on the solid domain of the tank. The theoretical background of hydrodynamic pressure analysis, as well as the numerical simulation of the liquid-filled cylindrical concrete tank, is the focus of this paper. The Finite Element Method (FEM) modeling, along with Arbitrary Lagrangian-Eulerian and Fluid-Structure Interactions formulation, are used for simulating the seismic response of cylindrical concrete liquid-filled tank, fixed to the rigid foundation. The Loma Prieta accelerogram is utilized for recording the seismic ground motion. In the numerical study, two states are observed: 1) static condition where only hydrostatic pressure acts, and 2) seismic excitation where hydrodynamic pressure occurs. When exposed to an earthquake situation, the tank liquid gives the total pressure of the liquid domain. The dynamic analysis considers the pressure response of the liquid domain, as well as the stress response of the solid domain of the coupled system, i.e., liquid-filled cylindrical concrete tank.
The Wish I Had Known Document as a learning aid and workplace time-saver
Roger Burks

Roger Burks

January 15, 2021
The Wish I had Known Document (WIHK-D) helps you remember how you solved problems, and is meant to be written while you are learning something. It should be used and expanded while you are trying to apply what you learned.Helps you easily communicate basic solutions to other beginners.Helps you remember how you solved obscure issues.Should retain a learner's perspective.Keeps crucial how-to information in an easily perused location.Complements other documentation as a valuable occupational aid.Best constructed while you are learning, and reviewed by experts before using as teaching aids.Can be made with greater technological sophistication, but do not go overboard.Why do you need extra documents to tell beginners how to do obscure things? You need them because hours of work time are wasted when beginners become frustrated while trying and failing to perform non-intuitive operations. They may not remember how to do something, or they may have never known. Regardless, a lack of simple learning and memory aids can waste time and can become stressful for many employees in an organization, including you. What if you could help new users start with all the knowledge that you wish you had known back when you started learning the same thing? What if you could do this efficiently? What if your expert go-to employee could quickly point to a document providing easy answers for co-workers, instead of doing their work for them?The ongoing challenge of remembering, learning, and teaching is part of what inspires us to create protocols, manuals, training videos, FAQs, and so forth. However, these are not perfect solutions. Large documents can hide information rather than indicate it. Large paragraphs in these documents can give the impression that valuable information is not currently in view, which can add to an already-present feeling of frustration. Nobody has time to read everything and perfectly retain it before applying knowledge. Instead, we read most earnestly exactly when we need to know something. FAQs are supposed to address this need, but many FAQs are written before user feedback is received and are often not very helpful beyond initial installation of a program.How-to videos are a special case, similar to seminars, in that they can help the viewer feel confident while they are being viewed. However, many of us learn and retain knowledge by doing instead of watching. Once we follow up on the presented topic, we can be very much surprised to learn that we do not know how to do that much. Additionally, videos and seminars often seem to completely cover a topic, but we may easily overlook how important connected details and perspectives have been unintentionally omitted.A WIHK-D differs from the above alternatives in that it is a practical quick reference, meant to be used while doing something. A WIHK-D should be concise and easy to reference, and it should feel refreshing because it quickly provides a solution that you desperately wanted.A WIHK-D is not a replacement for other documentation. It is meant to be used in conjunction with the manuals, protocols, videos, and seminars that do the heavy lifting in learning skills. When we learn something simple that we wish we had known, we add it to our personal WIHK-D for the topic, or we add it to the organizational WIHK-D if we want to help others quickly reference the same thing.The format is intentionally simple: an introductory category if you wish ('I want to...'), followed by problems and solutions, tasks and protocols, or questions and answers. Each line is kept as simple as possible while being explanatory, with steps or related information clearly visually associated with the problem or question. Proper visual organization of teaching aids is highly important: visual consistency and implied logic through visuals can teach people who had previously found the topic too daunting. The more approachable the arrangement and format, the broader the potential audience. Quick reference in simple text is achieved through the relatively unsophisticated but well-known method of using the Find function (Ctrl-F or Cmd-F) to find a keyword associated with an issue. Here is a plain text WIHK-D document that I created while learning Adobe Illustrator, which has many features that are not immediately obvious. See further below for solutions that go beyond a flat text document.
A short survey on the common Doctrines Between the Bektashi order and Shi'a Islam
SeyedAmirHossein Asghari

SeyedAmirHossein Asghari

January 15, 2021
A document by SeyedAmirHossein Asghari, written on Authorea.
Prevalence of Medical Humanities Teaching in Medical Schools: Review of Curricula in...
Jeremy Howick
Lunan Zhao

Jeremy Howick

and 6 more

January 15, 2021
Rationale and Objectives Medical humanities are becoming increasingly popular, required, and recognized as positively impacting medical education and medical practice. However, the extent of medical humanities teaching in medical schools is largely unknown. We aimed to review medical school curricula in Canada, the UK, and the US. Our secondary objective was to compare the inclusion of medical humanities in the curricula with rankings of medical schools. Methods We searched the curriculum websites of all accredited medical schools in Canada, the UK, and the US to check which medical humanities topics were taught, and whether they were mandatory or optional. We then noted rankings both by Times Higher Education and U.S. News and World Report and calculated the average rank. We formally explored whether there was an association between average medical school ranking and medical humanities offerings using Spearman’s correlation and inverse variance weighting meta-analysis. Results We identified 18 accredited medical school programmes in Canada, 41 in the UK, and 156 in the US. Of these, 9 (56%) in Canada, 34 (73%) in the UK and 124 (79%) in the US offered at least one medical humanity that was not ethics. The most common medical humanities were Unspecified Medical Humanities, History, and Literature (Canada), Sociology and Social Medicine, Unspecified Medical Humanities, and Art (UK), and Unspecified Medical Humanities, Literature, and History (US). There was a negative relationship between the ranking of the medical school and whether they offered medical humanities. Conclusions The extent and content of medical humanities offerings at accredited medical schools in Canada, the UK, and the US varies. The quality of our analysis was limited by the data provided on the Universities’ curriculum websites. Given the potential for medical humanities to improve medical education and medical practice, this variation should be investigated further.
Mosaic desert pavement influences water infiltration and vegetation distribution on f...
Dejin Wang
Wenzhi Zhao

Dejin Wang

and 3 more

January 15, 2021
Desert pavements are critical for maintaining ecological stability and promoting near-surface hydrological cycle in arid regions. However, few studies have reported the desert pavements on ecological on fluvial fans. Although desert pavement surfaces appear to be barren and flat, we found that the surfaces were featured by mosaic pattern of desert pavement (DP) and bare ground (BG). In this study, we investigated the effects of mosaic DP on water infiltration and vegetation distribution at six sites (i.e. one on the hillside and five in the sectors of fluvial fans) along a southwest belt transect on the fluvial fans in the Northern Linze County, in the middle of Hexi Corridor. The results showed that significant differences of Mosaic DP between hillside and sectors of fans were found in pavement thickness, thickness of vesicular horizon (Av thickness), particle composition and bulk density, rather than soil moisture content (SMC), gravel coverage and surface gravel size. The mosaic DP can inhibit water infiltration by pavement layer, where the sorptivity (S), initial infiltration rate (iint) and steady- state infiltration rate (isat) and infiltration time (T) averaged 1.30 cm/min-0.5, 5.03 cm/min, 0.23 cm/min, and 12.76 min respectively. If pavement layer was scalped, the S, iint and isat increased by 0.75 cm/min-0.5, 2.90 cm/min and 0.13 cm/min, respectively, and the T was shortened by 5.34 min. Water infiltration was mainly controlled by the pavement layer thickness (+), Av thickness (-), surface gravel coverage (-), and fine earth (+) and fine gravel (-) of pavement layer. Mosaic DP grew less shrubs than mosaic BG where distributed plenty of herbs. It can be concluded that desert pavements can keep vegetation stability by self-regulating rainfall. This study would deepen our understanding of the eco-hydrological cycle of pavement landscape in arid regions.
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