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Pediatric Hematology Providers’ Contraceptive Practices for Female Adolescents and Yo...
Megan Askew
Arlene Smaldone

Megan Askew

and 6 more

February 27, 2022
Background Adolescent and young adult (AYA) women with sickle cell disease (SCD) have increased pregnancy-related health risks and are prescribed potentially teratogenic medications, yet little is known about pediatric SCD provider contraceptive practices. We aimed to assess pediatric hematology providers’ beliefs, practices, motivators, and barriers for providing contraceptive care to female AYA with SCD. Methods Guided by the Health Belief Model (HBM), we developed a 25-question, web-based survey to assess providers’ practices. Survey links were distributed nation-wide to pediatric SCD and/or general hematology providers through their publicly available emails and by request to directors of U.S. accredited Pediatric Hematology-Oncology fellowship programs for distribution to their SCD providers. Data analysis included descriptive statistics, chi-square analysis, logistic regression. Results Of 177 respondents, 160 surveys meeting inclusion criteria were analyzed. Most providers reported counseling (77.5%) and referring female AYA patients for contraception (90.8%), but fewer reported prescribing contraception (41.8%). Counseling practices significantly differed in trainees versus established providers (54% vs. 85%, p<0.001) with a similar trend for prescribing (p=0.05). Prescription practices did not differ significantly by provider beliefs regarding potential teratogenicity of hydroxyurea. Key motivators included patient request and disclosure of sexual activity. Key barriers included inadequate provider training, limited visit time, and perceived patient/parent interest. Conclusion Provider contraceptive practices for female AYA with SCD varied, especially by provider status. Health beliefs regarding teratogenic potential of hydroxyurea did not correlate with contraceptive practices. Clinical guidelines, provider training, and patient/parent decision-making tools may be tested to assess whether provider contraceptive practices could be improved.
LEFT ATRIAL SHAPE AND FUNCTION AFTER ENDOVASCULAR DEVICE AND SURGICAL CLOSURE OF ASDS...
Andrey Smorgon
Sokolov Alexandr Anatolievich

Smorgon Andrey Vladimirovich

and 3 more

February 27, 2022
Retrospective analysis of echocardiograms was performed in 756 children who received endovascular device or surgical ASD closure from 2006 to 2016 in the Cardiac Center in Tomsk Russia. 564 patients had an endovascular closure and 192 had surgical correction. Follow-up duration was from 1 day to 10 years, mean 3.6 yrs for the device group and 4.2 yrs for the surgery group. The control group consisted of 3393 age-matched healthy patients. In patients with endovascular closure of an ASD, 35% had a change in the shape of the left atrium in early follow-up. Changes in the shape of the left atrium at early follow-up were more often observed in the device group and in children of a younger age. The left atrial changes were a decrease in sphericity and an increase in ellipsoidy. Changes in the shape of the left atrium persisted in 22% after transcatheter correction in the long-term. The change in shape of the left atrium after the placement of ASD devices was accompanied by activation of the mechanical function of the atrium and an increase in the filling pressure of the left ventricle. These changes were not accompanied by any disturbance in the contractility and volume of the heart chambers. In the group with surgical correction of ASD, the contractility and volume of the heart chambers did not significantly differ from those in the device closure group.
Clot in Transit: Early Intervention with Early Recovery
Casey Walk
Sarah Katchen

Casey Walk

and 2 more

February 27, 2022
48-year-old female presented with dyspnea and fatigue in June 2020. CT imaging found pulmonary embolus and a heparin drip was initiated. She later developed chest pain which led to an echocardiogram. This imaging noted biatrial thrombus extending through mitral and tricuspid valve, as well as through a patent foramen ovale (PFO) (Fig. 1, 2). She underwent emergent sternotomy, left and right atrial embolectomy, left and right pulmonary embolectomy, and atrial septal defect closure (Fig. 3). She progressed well post op and was discharged on postoperative day 7 on therapeutic anticoagulation. Remains in good condition on follow up on long term follow up.
Primary pericardial malignant mesothelioma: A case report and literature review
陈倩素
美林宫

qiansu Chen

and 2 more

February 27, 2022
Background : Primary pericardial malignant mesothelioma is a highly malignant and rare tumor. We present a case of primary pericardial malignant mesothelioma in an adult male patient and review the relevant literature to extend the understanding of the disease. Methods: The patient underwent pericardial decortication through the cardiopulmonary bypass, which effectively relieved the clinical symptoms caused by the tumor blockage. Results:Postoperative pathological diagnosis and immunohistochemistry resulted in primary pericardial malignant mesothelioma. The patient recovered after surgery and was followed up regularly after discharge. Conclusions: Primary pericardial malignant mesothelioma lacks characteristic clinical and imaging manifestations, invariably resulting in misdiagnosis. Pathological results combined with immunohistochemistry are the gold standard for diagnosis. Surgery is the mainstay of treatment, but the prognosis is extremely poor.
Metabolic Engineering of Oleaginous Yeast Rhodotorula toruloides for Overproduction o...
Mingfeng Cao
Vinh Tran

Mingfeng Cao

and 7 more

February 27, 2022
The plant-sourced polyketide triacetic acid lactone (TAL) has been recognized as a promising platform chemical for the biorefinery industry. However, its practical application was rather limited due to low natural abundance and inefficient cell factories for biosynthesis. Here we report the metabolic engineering of oleaginous yeast Rhodotorula toruloides for TAL overproduction. We first introduced a 2-pyrone synthase gene from Gerbera hybrida ( GhPS) into R. toruloides and investigated the effects of different carbon sources on TAL production. We then systematically employed a variety of metabolic engineering strategies to increase the flux of acetyl-CoA by enhancing its biosynthetic pathways and disrupting its competing pathways. We found that overexpression of citrate lyase (ACL1) improved TAL production by 45% compared to the GhPS overexpressing strain, and additional overexpression of acetyl-CoA carboxylase (ACC1) further increased TAL production by 29%. Finally, we characterized the resulting strain I12- ACL1-ACC1 using fed-batch bioreactor fermentation in glucose or oilcane juice medium with acetate supplementation and achieved a titer of 28 g/L or 23 g/L TAL, respectively. This study demonstrates that R. toruloides is a promising host for production of TAL and other acetyl-CoA-derived polyketides from low-cost carbon sources.
The morphological and ecological variation of Arctostaphylos (Ericaceae) fruit: a lin...
Rebecca E. Crowe
V. Thomas Parker

Rebecca Crowe

and 1 more

February 27, 2022
Persistent soil seed banks are characteristic of Arctostaphylos (Ericaceae) species in the Mediterranean-climate California Floristic Province. While most species are obligate seeders, regeneration of stands of all Arctostaphylos species ultimately depends on post-fire seedling recruitment. Arctostaphylos seed banks are created, in large part, by scatter-hoarding rodents. Variation in fruit morphology, therefore, is expected to impact the Arctostaphylos-rodent interaction. Seeds produce sufficient rewards (nutritious mature embryo) to entice rodents to disperse and ultimately bury seeds in the soil. Hard seed coats increase the time required to extract the embryo, encouraging rodents to choose storage over immediate predation, and endocarps are frequently empty. We assessed the variation of fruit endocarp fusion and seed viability among species of Arctostaphylos. Factors such as latitude, elevation, life history, ploidy, and phylogenetic position were also analyzed. Generalized mixed effects models were used to determine the factors contributing to variation in fruit endocarp fusion and viability. Our results indicate that fruit volume and shape are the most important variables affecting endocarp fusion and seed viability. Additionally, other potential influences only show a weak correlation and are not predicted to significantly impact fruit endocarp fusion or viability. These findings provide insight into evolved strategies used by plants to increase reproductive success via scatter-hoarding rodents. Our study benefits the conservation and restoration of Arctostaphylos stands by emphasizing the importance of animal-mediated dispersal and providing estimates of seed viability for different species. With the anticipated effects of climate change, such as departures from historic fire regimes, the preservation of the relationship between plants and animal foragers is crucial for the continued survival of Arctostaphylos and California’s evergreen chaparral.
Hyperbolic inverse mean curvature flow with forced term: evolution of plane curves
Ran Ding
Zenggui Wang

Ran Ding

and 1 more

February 27, 2022
The motion of plane curves specified by hyperbolic inverse mean curvature with a constant force term is considered. We proved that this flow remains the convexity for any forced term. Furthermore, we give an example to understand how the constant forced term $c$ affects this hyperbolic inverse mean flow. Particularly, the asymptotic behavior of the flow under different initial conditions is discussed.
Statement of concern: The current enthusiasm for vitamin D as an aid against Covid-19...
Dr. Carolina Diamandis

Dr. Carolina Diamandis

and 4 more

February 28, 2022
As a result of recommendations from some influencers on vitamin D as a helpful supplement against Covid-19, the number of people taking vitamin D as a regular dietary supplement has increased, as has the amount of the dose taken individually. As a globally active health network, the Lazar Medical Consortium Group (LCG) has access to privacy-protected patient data in more than 25 countries. We searched the records of 14.742 patients worldwide for vitamin D intake on record, onset as well as duration of intake, and symptoms coded according to ICD-10 that were consistent with vitamin D-related hypervitaminosis. The evaluation revealed evidence of a worldwide overuse of vitamin D so massive that medical providers working with the Lazar Medical Consortium Group have all received a Red Label Notice to educate patients at every patient contact against the danger of taking too much vitamin D (>1000. I.U. per day).
Analyzing the Effect of Using Axial Impellers in Large-Scale Bioreactors
Sören Bernauer
Philipp Eibl

Sören Bernauer

and 4 more

February 26, 2022
In high-performance industrial fermentation processes, stirring and aeration may account for significant production costs. Compared to the widely applied Rushton impellers, axial-pumping impellers are known to yield a lower power draw and at the same time improve mixing. However, their lower gas dispersion capability requires stronger agitation, compromising these benefits. Diverse advanced impeller forms have been developed to cope with this challenge. We apply alternating radial and axial impellers and demonstrate strong gas dispersion and energy-efficient mixing for the first time in a large-scale (160 m 3) bioreactor, based on experimental and CFD simulation data. For equal operating conditions (stirrer speed, aeration rate), this setup yielded similar gas hold-ups and better mixing times (-35 %) compared to a classical Rushton-only configuration. Hence, applying a radial impeller on an upper level for improving gas dispersion maintains the benefits of axial impellers in terms of reducing energy demand (up to -50 %). We conclude that this effect is significant only at large-scale, when bubbles substantially expand due to the release of the hydrostatic pressure and have time to coalesce. The work thus extends current knowledge on mixing and aeration of large-scale reactors using classical impeller types.
Radiofrequency Ablation: Four Decades Later, Still Optimizing Lesion Characterization
Alan Enriquez
Sharma Kattel

Alan Enriquez

and 1 more

February 26, 2022
Radiofrequency Ablation: Four Decades Later, Still Optimizing Lesion Characterization Alan D. Enriquez, M.D.1,2; Sharma Kattel MD, PhD11Section of Cardiovascular Medicine, Yale University School of Medicine, New Haven, CT2VA Connecticut Healthcare System, West Haven, CTFunding: NoneDisclosures: Boston Scientific – HonorariaWord count: 1304Corresponding Author:Alan D. Enriquez, MDCardiovascular MedicinePO Box 208017New Haven, CT 06520-8017alan.enriquez@yale.eduIntracardiac catheter ablation was first introduced in the early 1980s with a direct current shock used as the energy source. (1) Titration of energy delivery was difficult, and extensive tissue damage could occur. Radiofrequency (RF) ablation was first reported by Huang and colleagues in 1985 and has since become the cornerstone of catheter ablation. The technique and delivery of RF energy application has undergone significant modifications over the last two decades with the introduction of irrigated tip and contact force sensing catheters.The current standard RF generator produces 300-750 kHz of alternating sinusoidal current. During RF application, the current that transverses from the tip of the ablation catheter through intervening tissue to a dispersive electrode attached to patient’s body surface results in lesion formation through resistive and conductive heating, with tissue temperatures \(\geq\) 50o Celsius resulting in irreversible injury. (2) As higher current delivery may be limited due to char formation from rapid temperature rise in the tissue-catheter interface, irrigated RF was developed to overcome this limitation. Introduction of contact force sensing catheters has provided an additional tool to continuously assess catheter stability during RF delivery, thereby improving safety and efficacy. (3)Despite these advances, assessment of lesion quality during RF ablation remains challenging, and inadequate lesion formation plays a substantial role in the relatively high recurrence rates after atrial fibrillation and ventricular tachycardia ablation.(4,5) Current density is a primary determinant of lesion size and is dependent on multiple factors including RF power, size of the electrode tip, tissue contact, impendence, tissue-electrode interface temperature, tissue characteristics, and duration of energy delivery. Irrigated RF has rendered tip temperature unreliable as a predictor of tissue temperature, and accounting for all of these variables to reliably determine lesion size has been problematic.As a result, there has been significant interest in developing algorithms to predict the size of lesion formation to improve efficacy and safety of catheter ablation. Force Time Integral (FTI) and Lesion Size Index (LSI) have been developed for use with the TactiCathTM contact force sensing catheter and EnsiteTM Precision 3D mapping system (Abbott Medical, St. Paul, MN).FTI is defined as total contact force integrated over the time of RF delivery. While targeting FTI > 400 grams has been associated with improved outcomes in atrial fibrillation ablation (6,7), FTI does not account for power. LSI is calculated by aggregating contact force as well as current data across time with the intent to provide a more precise assessment of lesion formation. However, data regarding the accuracy of LSI in predicting lesion size and quality is sparse.In this issue, Themistoclakis et al evaluated lesion size for pre-specified values of LSI reached during RF delivery in vivo in a porcine heart. Using 3D electro-anatomical mapping as a reference, 64 RF lesions targeting LSI values of 4-6 using a fixed power output of 30 W in temperature control mode at 42° C and contact force of 10-30 grams were created in 7 porcine hearts using a TactiCath contact force sensing catheter. The hearts were then explanted, and lesions were examined histologically. Only 25 non-transmural lesions were used for complete analysis with the remainder excluded due to transmurality, macroscopically unidentifiable lesions, or inability to measure lesion width or depth because of unfavorable anatomic location of the lesions. Of note, all atrial lesions were transmural with LSI \(\geq\) 4, and only lesions in the right and left ventricles were included in the final analysis. The authors were able to show a strong linear correlation with LSI values and lesion width (r=0.87, p<0.00001) and depth (r=0.89, p<0.00001). At LSI values of 4, 5 and 6, lesion width corresponded to 4.6±0.6 mm, 7.3±0.8 mm and 8.6±1.2 mm respectively. Similarly, lesion depth at LSI values of 4, 5, and 6 corresponded to 2.6±0.8 mm, 4.7±0.6 mm and 7.2±1.1 mm respectively. Furthermore, compared with other lesion parameters (FTI, RF duration, impedance drop, average temperature, contact force, and power), LSI was the only independent predictor of lesion width and depth in multivariable regression analysis. Also, steam pops, char formation, and damage to surrounding structures were not observed in this study.This is the first in vivo study examining LSI and lesion width and depth, and the authors have demonstrated that LSI is highly correlated with lesion width and depth. Moreover, these findings are consistent with prior studies. A prior in vitro study using a porcine myocardial slab model also showed that LSI was predictive of lesion width and depth and was a stronger predictor compared to FTI (8). Another in vivo study by Whitaker et al showed that when a LSI of 5 is targeted in the right atrium of porcine hearts, a LSI(interlesion distance – LSI) \(\leq\) 1.5 was associated with contiguous lesions and no gaps in the ablation line. (9) Thus, this study supports LSI as a strong predictor of lesion size.Achieving adequate lesion depth and width during RF application is important to obtain transmurality and contiguous lesions respectively and to improve efficacy of radiofrequency ablation. In some situations, it may also be important to limit lesion depth to prevent collateral damage to adjacent structures, such as avoiding esophageal damage when ablating in the posterior left atrium. Hence, LSI is a potentially powerful tool to assess lesion size during ablation in real-time. The authors proposed formulas for estimation of lesion width and depth using LSI based on their linear regression model (W(mm)= -4.21+2.17*LSI, and D(mm)=-7.54+2.54* LSI ). Using these equations, they proposed LSI values to achieve transmural lesions at different locations in the left atrium (LA) during pulmonary vein isolation (PVI) based on average human LA thickness (posterior wall = 4.1 mm, LSI ≥ 4.8; ridge between appendage and pulmonary vein = 5.0 mm, LSI ≥ 5.2; or interatrial septum = 5.5 mm, LSI ≥ 5.4) . There are clinical data supporting targeting pre-specified LSI values during PVI. There are small studies showing improved outcomes with PVI when the mean LSI achieved Is > 5.0. (10,11) Kanamori et al showed that an LSI < 5.25 anteriorly and < 4.0 posteriorly was associated with conduction gaps after PVI and suggested target LSI values of\(\geq\ \)5.2 anteriorly and \(\geq\) 4.0 posteriorly (areas adjacent to the espohagus) to obtain durable pulmonary vein isolation. (12) Adverse events were also not more frequent in patients with higher LSI values.While the findings of this study are compelling, there are limitations in applying these LSI findings to clinical practice. There were a relatively small number of lesions included in the study, and there are inherent differences in tissue heterogeneity, thickness, blood flow, body surface, and impedance values in porcine hearts compared to human hearts. In addition, these findings are most applicable to ablation in the ventricles since atrial lesions were excluded from the final analysis due to transmurality, though LSI had similar correlation with lesion width in the atrial lesions. It is also important to note that these LSI values were obtained at a fixed power of 30 W and using saline irrigation. These correlations may not hold true for different power settings or other irrigation fluids (e.g. half-normal saline), especially with the use of high power due to nonlinear behavior of tissue heating from an initial rapid resistive heating in early phase to more conductive heating in the later phase.The findings of this study combined with the existing literature support LSI as a clinically relevant surrogate for lesion size. Targeting LSI values of 4-6 appears to be safe, and LSI may be used as an adjunctive tool in conjunction with other parameters of RF ablation to estimate lesion size. However, caution must still be exercised, and there are no established LSI targets for atrial fibrillation and ventricular tachycardia ablation. While progress is being made in characterizing lesions during ablation, further studies are required to confirm the efficacy of using LSI and to establish optimal LSI target values.References1. Andrade JG, Rivard L, Macle L. The past, the present, and the future of cardiac arrhythmia ablation. Can J Cardiol 2014;30:S431-41.2. Nath S, DiMarco JP, Haines DE. Basic aspects of radiofrequency catheter ablation. J Cardiovasc Electrophysiol 1994;5:863-76.3. Yokoyama K, Nakagawa H, Shah DC, Lambert H, Leo G, Aeby N, Ikeda A, Pitha JV, Sharma T, Lazzara R, Jackman WM. Novel contact force sensor incorporated in irrigated radiofrequency ablation catheter predicts lesion size and incidence of steam pop and thrombus. Circ Arrhythm Electrophysiol 2008;1:354-62.4. Packer DL, Mark DB, Robb RA, Monahan KH, Bahnson TD, Poole JE, Noseworthy PA, Rosenberg YD, Jeffries N, Mitchell LB, Flaker GC, Pokushalov E, Romanov A, Bunch TJ, Noelker G, Ardashev A, Revishvili A, Wilber DJ, Cappato R, Kuck KH, Hindricks G, Davies DW, Kowey PR, Naccarelli GV, Reiffel JA, Piccini JP, Silverstein AP, Al-Khalidi HR, Lee KL, Investigators C. Effect of Catheter Ablation vs Antiarrhythmic Drug Therapy on Mortality, Stroke, Bleeding, and Cardiac Arrest Among Patients With Atrial Fibrillation: The CABANA Randomized Clinical Trial. JAMA 2019;321:1261-1274.5. Sapp JL, Wells GA, Parkash R, Stevenson WG, Blier L, Sarrazin JF, Thibault B, Rivard L, Gula L, Leong-Sit P, Essebag V, Nery PB, Tung SK, Raymond JM, Sterns LD, Veenhuyzen GD, Healey JS, Redfearn D, Roux JF, Tang AS. Ventricular Tachycardia Ablation versus Escalation of Antiarrhythmic Drugs. N Engl J Med 2016;375:111-21.6. Neuzil P, Reddy VY, Kautzner J, Petru J, Wichterle D, Shah D, Lambert H, Yulzari A, Wissner E, Kuck KH. Electrical reconnection after pulmonary vein isolation is contingent on contact force during initial treatment: results from the EFFICAS I study. Circ Arrhythm Electrophysiol 2013;6:327-33.7. Kautzner J, Neuzil P, Lambert H, Peichl P, Petru J, Cihak R, Skoda J, Wichterle D, Wissner E, Yulzari A, Kuck KH. EFFICAS II: optimization of catheter contact force improves outcome of pulmonary vein isolation for paroxysmal atrial fibrillation. Europace 2015;17:1229-35.8. Calzolari V, De Mattia L, Indiani S, Crosato M, Furlanetto A, Licciardello C, Squasi PAM, Olivari Z. In Vitro Validation of the Lesion Size Index to Predict Lesion Width and Depth After Irrigated Radiofrequency Ablation in a Porcine Model. JACC Clin Electrophysiol 2017;3:1126-1135.9. Whitaker J, Fish J, Harrison J, Chubb H, Williams SE, Fastl T, Corrado C, Van Zaen J, Gibbs J, O’Neill L, Mukherjee R, Rittey D, Thorsten J, Donskoy E, Sohal M, Rajani R, Niederer S, Wright M, O’Neill MD. Lesion Index-Guided Ablation Facilitates Continuous, Transmural, and Durable Lesions in a Porcine Recovery Model. Circ Arrhythm Electrophysiol 2018;11:e005892.10. Dello Russo A, Fassini GM, Casella M, Romanelli E, Pala S, Riva S, Catto V, Moltrasio M, Tundo F, Zucchetti M, Majocchi B, Dessanai MA, Pizzamiglio F, Vettor G, Ribatti V, Gasperetti A, Cellucci S, Negro G, Sicuso R, Carbucicchio C, Tondo C. Lesion index: a novel guide in the path of successful pulmonary vein isolation. J Interv Card Electrophysiol 2019;55:27-34.11. Mattia L, Crosato M, Indiani S, Causin E, Licciardello C, Maria Squasi PA, De Leo A, Calzolari V. Prospective Evaluation of Lesion Index-Guided Pulmonary Vein Isolation Technique in Patients with Paroxysmal Atrial Fibrillation: 1-year Follow-Up. J Atr Fibrillation 2018;10:1858.12. Kanamori N, Kato T, Sakagami S, Saeki T, Kato C, Kawai K, Chikata A, Takashima SI, Murai H, Usui S, Furusho H, Kaneko S, Takamura M. Optimal lesion size index to prevent conduction gap during pulmonary vein isolation. J Cardiovasc Electrophysiol 2018;29:1616-1623.
Sex-specific changes in autosomal methylation rate in ageing common terns
Britta Meyer
Maria Moiron

Britta Meyer

and 13 more

February 26, 2022
Senescence, an age-related decline in survival and/or reproductive performance, occurs in species across the tree of life. Molecular mechanisms underlying this within-individual phenomenon are still largely unknown, but DNA methylation changes with age are among the candidates. Using a longitudinal approach, we investigated age-specific changes in autosomal methylation of common terns, relatively long-lived migratory seabirds known to show senescence. We collected blood at 1-, 3- and/or 4-year intervals, extracted DNA from the erythrocytes and estimated autosomal DNA methylation by mapping Reduced Representative Bisulfite Sequencing reads to a new reference genome. We found autosomal methylation levels to decrease with age within females, but not males, and no evidence for selective (dis)appearance of birds of either sex in relation to their methylation level. Moreover, although we found positions in the genome to consistently differ in their methylation levels, individuals did not show such strong consistent differences. These results pave the way for studies at the level of genome features or specific positions, which should elucidate the functional consequences of the patterns we observe, and how they translate to the ageing phenotype.
Experimental Study on the Anisotropic Cracking Behavior of Shale under Compression an...
shengxiangchao
Lei Yang

Xiangchao Sheng

and 5 more

February 26, 2022
To gain insight into the anisotropic mechanical properties and failure behavior of shale, the cracking behavior of shale under compression and tension was investigated experimentally from the macroscopic and microscopic perspectives. The uniaxial compression tests were first carried out, and the effects of bedding plane on the generation of microcracks were analyzed through the technology of nuclear magnetic resonance. Then, the Brazilian splitting and confocal laser scanning microscopy tests were performed, and the corresponding relation between the failure mode and the fracture surface morphology was discussed. The results reveal that the mechanical properties and failure modes of shale are affected significantly by the existence of bedding planes. The distribution characteristics of microflaw radius and porosity change significantly due to the action of uniaxial compression, and the highest porosity of newly-generated microcracks is that of the 0° specimen. The newly-generated microflaws in 0°, 30° and 90° specimens are mainly contributed by seepage microflaws, while those in 60° specimen are mainly contributed by capillary microflaws. In the Brazilian splitting test, the fracture surface morphology of the specimen is significantly affected by the bedding angle, and the fracture surface morphology of the specimen is closely related to the failure mode and mechanism.
Shape and sample size impacts on time-based home range estimates
Brendan Hoover
Jennifer Miller

Brendan Hoover

and 1 more

February 26, 2022
Home range estimates have been a key geographic unit for understanding the link between animals and their habitat/resource choices since the term was first described by Burt (1943) and formally quantified by Mohr (1947)—who introduced minimum convex polygons (MCP) as a method to delineate individual home ranges. Numerous methods have subsequently been developed to estimate home ranges. However, depending on the method used, widely different estimations can be found with the same animal location dataset. With different home range delineations, inferences in a heterogenous landscape about animal resource and habitat preferences with different delineations can impact wildlife management. In this research, time-based home range methods that account for autocorrelation in animal movement were evaluated for accuracy in terms of area, shape, and location in response to sample size and common wildlife GPS-point patterns. These characteristics of home range estimation are important for inferring animal habitat and resource use. Despite the improved accuracy of time-based methods compared to traditional point-based methods like MCP, location was often inaccurate for all GPS-point patterns, as were shape and area for GPS-point patterns with perforations (common for areas with large physical barriers like mountains or lakes). These findings are important to wildlife managers using time-based home range methods for analysis.
Area Deprivation and Respiratory Morbidities in Children with Bronchopulmonary Dyspla...
Emma Banwell
Joseph Collaco

Emma Banwell

and 6 more

February 25, 2022
Introduction: Infants and children diagnosed with BPD have a higher likelihood of recurrent hospitalizations and asthma-like symptoms. Socio-environmental factors that influence frequency and severity of pulmonary symptoms in these children during the pre-school age are poorly under-stood. In this study, we used the Area Deprivation Index (ADI) to evaluate the relationship between the socio-environmental exposures in children with BPD and respiratory outcomes during the first few years of life. Methods: A registry of subjects recruited from outpatient BPD clinics at Johns Hopkins University (n=909) and the Children’s Hospital of Philadelphia (n=125) between January 2008 and October 2021 was used. Subjects were separated into tertiles by ADI scores aggregated to ZIP codes. Care-giver questionnaires were used to assess the frequency of respiratory morbidities and acute care usage for respiratory symptoms. Results: The mean gestational age of subjects was 26.8±2.6 weeks with a mean birthweight of 909±404 grams. The highest tertile (most deprived) of ADI was significantly associated with emer-gency department visits (aOR 1.72; p=0.009), hospital readmissions (aOR 1.66; p=0.030), and activi-ty limitations (aOR 1.55; p=0.048) compared to the lowest tertile. No association was seen with steroid, antibiotic or rescue medication use, trouble breathing, or nighttime symptoms. Conclusion: In this study, children with BPD who lived in neighborhoods of higher deprivation were more likely to be re-hospitalized and have ED visits for respiratory reasons. Identifying socio-environmental factors that contribute to adverse pulmonary outcomes in children with BPD may provide opportunities for earlier interventions to improve long-term pulmonary outcomes.
Septic shock, acute renal and liver failure following unsafe abortion using bitter le...
Gasthony Alobo
Cristina Reverzani

Gasthony Alobo

and 4 more

February 25, 2022
This case series describes the unusual severe toxicity of two herbal medicines that are frequently used to induce abortion in Northern Uganda. It highlights possible associations of Commelina Africana (wandering jew) with uterine necrosis complicated by and sepsis, and of Vernonia amygdalina (bitter leaf) with acute liver and renal failure
Drug induced vasculitis , Thiazide or COVID-vaccine ? : A case report and literature...
Manoochehr Hekmat
 Sepideh Jafari Naeini

Manoochehr Hekmat

and 3 more

February 25, 2022
A middle-aged woman with history of the administration of COVID-19 vaccine and valve replacement surgery before her symptoms, was admitted with bilateral palpable purpuric lesions in the lower extremities and headache . Based on the initial diagnosis of vasculitis , corticosteroid therapy was initiated and resolved the skin lesion
Parents experiences of handling oral anticancer drugs at home: “It all falls on me …”
Ranaa Akkawi El Edelbi
Staffan Eksborg

Ranaa Akkawi El Edelbi

and 6 more

February 25, 2022
Aim: The aim of this study was to describe the experiences of parents handling oral anticancer drugs in a home setting. Methods: Parents of children with cancer were recruited from a pediatric oncology ward in Sweden to participate in an interview. The interviews were transcribed verbatim and subjected to qualitative content analysis. Results: We found the following categories and subcategories: parents’ views on the provided information - lack of, too little or contradictory information, and parents’ preferences for information delivery; safety over time; correct drug dose; and drug administration. As time passed, most parents adapted to their child’s illness, felt safer, and found it easier to take in and process any given information. Parents preferred information in different formats (written, movie clips and orally) and in their mother tongue. Many parents were aware of the importance of giving an accurate dose to their child and described the process of drug administration as overwhelming. Conclusions: Parents need to be provided with accurate, timely, nonconflicting and repeated information – in different forms and in their mother tongue – on how to handle oral anticancer drugs at home.
An elderly woman with an indurated plaque on the right Buttock
Mariem Rekik
kouki chaima

Mariem Rekik

and 9 more

February 25, 2022
Malignant melanoma presenting as an inflammatory skin metastasis has been described but is an exceedingly rare phenomenon. We report a case of inflammatory metastasis of cutaneous melanoma (CM)
Fat necrosis: a neglected side effect of intramuscular injections.
kouki chaima
mariem Amouri

kouki chaima

and 6 more

February 25, 2022
Fat necrosis (FN) is an uncommon etiology of panniculitis. It is mainly caused by trauma and may be associated to other conditions such as pancreatic disease. We report an interesting case of subcutaneous FN caused by intramuscular injections of cefazolin and meglumine antimoniate in a 38-year-old female patient.
Short INDELs and SNPs as markers of evolutionary processes in hybrid zones
Samuel Perini
Kerstin Johannesson

Samuel Perini

and 3 more

February 25, 2022
Polymorphic short insertions and deletions (INDELs ≤ 50 bp) are abundant, although less common than single nucleotide polymorphisms (SNPs). Evidence from model organisms shows INDELs to be more strongly influenced by purifying selection than SNPs. Partly for this reason, INDELs are rarely used as markers for demographic processes or to detect balancing or divergent selection. Here, we compared INDELs and SNPs in the intertidal snail Littorina saxatilis, focusing on hybrid zones between ecotypes. Using capture sequencing data, we computed INDEL and SNP site frequency spectra (SFS) to compare the impact of purifying, positive and balancing selection on these variant types. Because signatures of selection may be confounded by GC-biased gene conversion and polarization errors, we also examined their influence. We assessed the impact of divergent selection by analysing allele frequency clines across habitat boundaries. We show evidence that short INDELs are affected more by purifying selection and less by positive selection than SNPs, but part of the observed SFS difference can be attributed to GC-biased gene conversion and polarization errors. We did not find a difference in the impact of balancing or divergent selection between short INDELs and SNPs. Short INDELs and SNPs were similarly distributed across the genome and so are likely to respond to indirect selection in the same way. A few regions likely affected by divergent selection were revealed by INDELs and not by SNPs. Short INDELs can be useful genetic markers helping to identify genomic regions under selective constraints or important for adaptation and population divergence.
Incidence of early and late onset group B streptococcal and Escherichia coli neonatal...
Viola Chan
Shuk Yi Annie Hui

Viola Chan

and 11 more

February 25, 2022
Objective: To compare the incidences of early and late onset neonatal sepsis, including group B streptococcus (GBS) and Escherichia coli (E.coli) before and after implementation of universal screening. Design: Retrospective cohort study Setting: Eight public hospitals with obstetrics services under the Hospital Authority and 31 Maternal and Child Health Centres (MCHC) under the Department of Health in Hong Kong Population: 460552 women attending routine antenatal service from 2009 to 2020. Methods: Universal culture-based GBS screening was offered to eligible women since 2012. Total maternity, births, GBS screening tests, GBS isolated in maternal genital tract, neonatal sepsis with positive blood or cerebrospinal fluid were retrieved from clinical and laboratory database of the Hospital Authority using clinical data analysis and reporting system (CDARS) and clinical system of MCHCs. Main outcome measures: Maternal GBS colonisation rate, early onset GBS disease, early onset E. coli infection, late onset GBS disease, and late onset E. coli infection Results: Of 318740 women with universal culture-based screening, 63767 women (20.0%) were screened positive. After implementation of GBS screening, the incidences of both early and late onset neonatal sepsis reduced significantly, including those caused by GBS. There was no change in the incidence of early onset E.coli sepsis, while the incidence of late onset E.coli sepsis reduced. Conclusions: Universal culture-based GBS screening in Hong Kong has been successful in prevention of early and late onset neonatal sepsis, including those caused by GBS. E.coli has become more common than GBS in early neonatal sepsis, although the incidence remained similar.
Contemporary GIS needed skills to accommodate the changing geospatial technologies
Anwar-Elsadat Elmahal

Anwar-Elsadat Elmahal

February 25, 2022
A document by Anwar-Elsadat Elmahal. Click on the document to view its contents.
Environmental RNA degrades more rapidly than environmental DNA across a broad range o...
Kaushar Kagzi
Robert M. Hechler

Kaushar Kagzi

and 3 more

February 25, 2022
Although the use and development of molecular biomonitoring tools based on eNAs (environmental nucleic acids; eDNA and eRNA) have gained broad interest for the quantification of biodiversity in natural ecosystems, studies investigating the impact of site-specific physicochemical parameters on eNA-based detection methods (particularly eRNA) remain scarce. Here, we used a controlled laboratory microcosm experiment to comparatively assess the environmental degradation of eDNA and eRNA across an acid-base gradient following complete removal of the progenitor organism (Daphnia pulex). Using water samples collected over a 30-day period, eDNA and eRNA copy numbers were quantified using a droplet digital PCR (ddPCR) assay targeting the mitochondrial cytochrome c oxidase subunit I (COI) gene of D. pulex. We found that eRNA decayed more rapidly than eDNA at all pH conditions tested, with detectability—predicted by an exponential decay model—for up to 57 hours (eRNA; neutral pH) and 143 days (eDNA; acidic pH) post organismal removal. Decay rates for eDNA were significantly higher in neutral and alkaline conditions than in acidic conditions, while decay rates for eRNA did not differ significantly among pH levels. Collectively, our findings provide the basis for a predictive framework assessing the persistence and degradation dynamics of eRNA and eDNA across a range of ecologically relevant pH conditions, establish the potential for eRNA to be used in spatially and temporally sensitive biomonitoring studies (as it is detectable across a range of pH levels), and may be used to inform future sampling strategies in aquatic habitats.
Social structure affects the gut microbiota in honey bees: The physiological cost of...
Duan Copeland
Brendon  Mott

Duan Copeland

and 2 more

February 25, 2022
Honey bees exhibit an elaborate social structure that corresponds with worker aging and division of labor. Young workers perform tasks inside the hive, while older workers forage outside the hive. Critical to colony fitness, the work force can respond rapidly to changes in the environment or colony demography and assume emergency tasks, resulting in young foragers or old nurses. We hypothesized that social structure affects the microbiome, more specifically, that behavioral task independent of age would generate differences in gut microbiota and host physiology. We used high throughput sequencing to track gut microbial succession, and measured gene expression and oxidative protein damage associated with behavioral task and age. We found that both age and behavioral task could explain differences in midgut and ileum microbiota, but host gene expression was best explained by an interaction of task and age. An extended nursing role in early life stabilized the ratio abundance of G. apicola and S. alvi in the ileum, while precocious foraging resulted in poor G. apicola establishment, nutrient deficient gene expression, and increased oxidative damage. Our results suggest that the physiological cost of early foraging is extreme, and highlight the progression of colony dwindling, a common but misunderstood process.
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