bluuebunny/crossref_metadata_2025 huggingface dataset:
Increased risk of ischemic heart disease and diabetes in inflammatory bowel disease
Authors: Li Zhihui , Qiao Lili , Yun Xiaojing , Du Fangjuan , Xing Shilei , Yang Maowu
Published: November 2020

Background Previous studies showed inconsistent results regarding associations between inflammatory bowel disease (IBD) and risk of ischemic heart disease (IHD) and diabetes. The present study aimed to make a meta-analysis to assess the risk of IHD and diabetes in IBD.

Methods We searched for articles published before February 2020 in the databases as follows: PubMed, Web of Science, Medline, EMBASE, and Google Scholar. We computed odds ratio (OR) or relative risk (RR) and 95 % confidence intervals (CI) regarding the association between IBD and risk of IHD or diabetes by using STATA 13.0 software.

Results The present meta-analysis showed that IBD was associated with higher risk of IHD (OR/RR = 1.26, 95 % CI 1.20 to 1.32, I2 = 88.3 %, p < 0.0001). Additionally, both ulcerative colitis (UC) and Crohn’s disease (CD) were associated with higher risk of IHD (UC: OR/RR = 1.19, 95 % CI 1.13 to 1.26, I2 = 65.6 %, p = 0.001; CD: OR/RR = 1.33, 95 % CI 1.17 to 1.51, I2 = 89.5 %, p < 0.0001). The study showed that IBD was associated with elevated risk of diabetes (OR/RR = 1.26, 95 % CI 1.03 to 1.53, I2 = 92.1 %, I2 = 92.1 %, p < 0.0001). Additionally, both UC and CD were associated with higher risk of diabetes (UC: OR/RR = 1.33, 95 % CI 1.03 to 1.71, I2 = 93.8 %, p < 0.0001; CD: OR/RR = 1.39, 95 % CI 1.10 to 1.76, I2 = 76.7 %, p = 0.002).

Conclusion In conclusion, patients with IBD are at increased risk of IHD and diabetes. Thus, regular monitoring of biomarkers of IHD and blood glucose levels should be considered for the early detection of IHD and diabetes in IBD patients.
Corona Pandemie und finanzielle Stabilität der gesetzlichen Krankenversicherung
Authors: Ulrich Volker
Published: November 2020

Die Corona-Pandemie zeigt, dass Deutschland über ein durchaus resilientes Gesundheitssystem verfügt, insbesondere auch im internationalen Vergleich. Die anfallenden coronabedingten Mehrausgaben sollten weitgehend über Steuern finanziert werden. Das erscheint angemessen, da die Mehrausgaben bei den Krankenkassen vielfach GKV-fremde Leistungen betreffen, zum Beispiel Schutzausrüstungen, flächendeckende Tests und später auch Impfungen (zumindest der externalisierende Teil der Impfung). Diese sind aus Steuermitteln zu tragen, da sie Maßnahmen der öffentlichen Daseinsvorsorge darstellen.

Der Spielraum für Steuererhöhungen ist allerdings begrenzt, will man nicht nur die Besserverdienenden belasten, wodurch deren Grenzbelastung ansteigen würde, mit negativen Effekten für Wachstum und Beschäftigung. Auch Beitragssatzsteigerungen sind unter dem Aspekt der Lohnnebenkosten nicht das Instrument erster Wahl. Unterm Strich dürften vor allem Steuern, neue Schulden und der Rückgriff auf die Reserven des Gesundheitsfonds stehen. Verschuldung ist wiederum unter Nachhaltigkeitsaspekten nicht unbedenklich, belastet es doch einseitig die kommenden Generationen. Das Dilemma besteht allerdings darin, dass es keinen bequemen Lösungsweg für die langfristige Finanzierung der GKV gibt. Durch die Corona-Pandemie entstehen Kosten, die es zu finanzieren gilt. Allerdings werden ausschließlich einnahmenseitige Maßnahmen, wie radikal auch immer, kaum der Königsweg zur Lösung der Finanzierungsprobleme sein. Hier müssen auch die ausgabenintensiven Gesetze der zurückliegenden und laufenden Legislaturperioden genannt werden. Ohne weitere Anstrengungen zur Begrenzung bzw. zur Anreizverbesserung auf der Ausgabenseite wird eine stabile Lösung kaum gelingen. Dies impliziert auch, dass eine offene Debatte über weitere Vernetzungsmöglichkeiten im Gesundheitswesen, über die Überwindung der Sektorengrenzen, die Förderung der Prävention oder über den Umfang des Leistungskatalogs unausweichlich erscheint.
Wohnsituation von Menschen mit Substanzgebrauchsstörungen im akut-psychiatrischen Behandlungssetting in Berlin – eine querschnittliche Patientenbefragung
Authors: Schreiter Stefanie , Fritz Francesco Domenico , Rössler Wulf , Majić Tomislav , Schouler-Ocak Meryam , Krausz Michael R. , Bermpohl Felix , Gutwinski Stefan
Published: November 2020

Ziel der Studie Untersuchung der Wohnsituation, Nutzung des Versorgungssystems und des Substanzgebrauchs bei Patienten1 mit Substanzgebrauchsstörungen in (teil-)stationärer psychiatrischer Behandlung in der Psychiatrischen Universitätsklinik der Charité im St. Hedwig-Krankenhaus.

Methode Strukturiertes Interview von 540 Patienten.

Ergebnisse Patienten in instabilen Wohnformen wiesen signifikant häufiger eine komorbide psychotische Störung auf und wurden signifikant früher psychiatrisch und suchttherapeutisch behandelt als Patienten in stabiler Wohnform, durchschnittlich bereits vor Beginn der Wohnungslosigkeit.

Schlussfolgerung Wohnungslosigkeit ist bei Menschen mit Suchterkrankungen in psychiatrischer Behandlung mit ungünstigen Verlaufsparametern verbunden, wie frühes Behandlungsalter und komorbide psychotische Störungen. Bei diesen Gruppen sollte daher besondere Berücksichtigung der sozialen Situation erfolgen und eine Zusammenarbeit der verschiedenen Versorgungsbereiche angestrebt werden.
In vivo Histology of the Cornea – from the “Rostock Cornea Module” to the “Rostock Electronic Slit Lamp” – a Clinical “Proof of Concept” Study
Authors: Bohn Sebastian , Stahnke Thomas , Sperlich Karsten , Linke Stephan J. , Farrokhi Sanaz , Klemm Maren , Allgeier Stephan , Köhler Bernd , Reichert Klaus-Martin , Witt Martin , Stachs Oliver , Guthoff Rudolf F.
Published: November 2020

Introduction Confocal in vivo microscopy is an established method in ophthalmology research. As it requires contact coupling and calibration of the instruments is suboptimal, this method has been only rarely used in clinical routine work. As a result of close collaboration between physicists, information scientists and ophthalmologists, confocal laser scanning microscopy (CLSM) of the eye has been developed in recent years and a prototype can now be used in patients. The present study evaluates possible clinical uses of this method.

Material and Methods The essential innovations in CLSM are (1) a newly designed coupling element with superficial adaptation to corneal curvature and (2) the use of a dual computerised piezo drive for rapid and precise focusing. In post-processing and after elastic imaging registration of the individual images parallel to the surface, it is also possible to produce sagittal sections resembling a split lamp and with resolution in the micrometer range. The concept was tested on enucleated pig bulbi and tested on normal volunteers and selected patients with diseases of the cornea.

Results Simultaneous imaging in planes parallel to the surface and in sagittal planes provided additional information that can help us to understand the processes of wound healing in all substructures of the cornea and the role of immune competent cells. Possible clinical uses were demonstrated in a volunteer with healthy eyes and several groups of patients (keratoconus after CXL, recurrent keratitis, status after PRK). These show that this new approach can be used in morphological studies at cellular level in any desired and appropriate test plane.

Conclusions It could be shown that this new concept of CLSM can be used clinically. It can provide valuable and novel information to both preclinical researchers and to ophthalmologists interested in corneal disease, e.g. density of Langerhans cells and epithelial stratification in ocular surface diseases.
Laparoscopic Management of Mechanical Small Bowel Obstruction Secondary to Meckel's Diverticulum with a Double Basis. A Rare Anatomic Presentation
Authors: Mariani Aurora , Siddiqui Mohammed , Boulard Nicolas , Berrebi Dominique , Bonnard Arnaud
Published: November 2020

Meckel's diverticulum (MD) is the most common congenital abnormality of the gastrointestinal tract. Intestinal occlusion due to MD is a commonly observed consequence of intussusception or volvulus. Here, we report a case of an 11-year-old boy who presented to the emergency department with acute abdominal pain, bilious vomiting, and abdominal rebound tenderness. Computed tomography scan concluded a diagnosis of intestinal occlusion with no apparent cause. The patient was submitted to diagnostic laparoscopy, and mechanical occlusion by the permeable Meckel with double base was identified. A diverticulectomy by staplers was performed, and occlusion was alleviated. MD is a rare disease (for only 0.3–2.9% of the general population), and only 4.2 to 9% of patients diagnosed with MD have associated complications. MD can be a large base or a narrow base, with a mesodiverticular band but the diverticulum is usually a blind recess. In our case, the tube connected two intestinal segments. To the best of our knowledge, we have reported the first case of an MD-like permeable tube with a double basis.
Endoscopic Transnasal Odontoidectomy
Authors: Zoia Cesare , Bongetta Daniele , Luzzi Sabino
Published: November 2020

Background Odontoidectomy may represent the treatment of choice for symptomatic ventral craniovertebral junction stenosis in selected cases. An endoscopic transnasal approach has been proposed as an alternative to a classic transoral approach.

Method We report a case of a patient with a craniovertebral junction stenosis due to the ossification of the posterior ligament. The clinical and radiological records of the patient and a step-by-step description of the surgical technique are presented (Fig. 1).

Conclusion Endoscopic transnasal odontoidectomy provides a direct access to the dens and adjacent structures of the anterior upper cervical spine with a less invasive burden on the oropharingeal structures.

The link to the video can be found at: https://youtu.be/Ofrk1sFTV9I.
Possible Role of High-Dose Barbiturates and Early Administration of Parenteral Ketogenic Diet for Reducing Development of Chronic Epilepsy in Febrile Infection-Related Epilepsy Syndrome: A Case Report
Authors: Baba Shimpei , Okanishi Tohru , Ohsugi Koichi , Suzumura Rika , Niimi Keiko , Shimizu Sayuri , Sakihama Hiroshi , Itamura Shinji , Hirano Keiko , Nishimura Mitsuyo , Fujimoto Ayataka , Enoki Hideo
Published: November 2020

We describe the efficacy of high-dose barbiturates and early administration of a parenteral ketogenic diet (KD) as initial treatments for acute status epilepticus (SE) in an 8-year-old girl with febrile infection-related epilepsy syndrome (FIRES). The patient was admitted to our hospital with refractory focal SE. Abundant epileptic discharges over the left frontal region were observed on electroencephalogram (EEG). Treatment with continuous infusion of thiamylal for 4 hours, increased incrementally to 40 mg/kg/h, successfully ended the clinical SE, and induced a burst-suppression coma. The infusion rate was then gradually decreased to 4 mg/kg/h over the next 12 hours. Parenteral KD was administered from days 6 to 21 of illness. Continuous infusion of thiamylal was switched to midazolam on day 10 without causing seizures or EEG exacerbations. The patient has remained seizure free in the 15 months since hospital discharge. The effectiveness of KD for the treatment of FIRES has attracted attention amongst clinicians, but KD treatment may need to last for 2 to 4 days before it can stop SE, a time period that could cause irreversible brain damage. Considering the severity of SE in our patient and the dose of barbiturates needed to treat it, we consider this case to have had a good clinical outcome. The results suggest that rapid termination of seizure using high-dose barbiturates in conjunction with early administration of parenteral KD could reduce the development of chronic epilepsy in patients with FIRES.
Transvaginal Sonographic Imaging and Associated Techniques for Diagnosis of Ovarian, Deep Endometriosis, and Adenomyosis: A Comprehensive Review
Authors: Aas-Eng Mee Kristine , Montanari Eliana , Lieng Marit , Keckstein Joerg , Hudelist Gernot
Published: November 2020

Imaging of endometriosis and in particular deep endometriosis (DE) is crucial in the clinical management of women facing this debilitating condition. Transvaginal sonography (TVS) is the first-line imaging method and magnetic resonance imaging (MRI) may provide supplemental information. However, the delay in diagnosis of up to 10 years and more is of concern. This problem might be overcome by simple steps using imaging with emphasis on TVS and referral to tertiary care. Finally, TVS is crucial in mapping extent and location of disease in planning surgical therapy and counseling women regarding various therapeutic options. This review presents the available data on imaging of endometriosis with a focus on TVS and MRI for DE, adenomyosis, and ovarian endometriomas including endometriomas in pregnancy as well as the use of “soft markers.” The review presents an approach that is in accordance with the International Deep Endometriosis Analysis (IDEA) group consensus statement.
Risk Factors and Predictors of Rebound Hyperbilirubinemia in a Term and Late-Preterm Infant with Hemolysis
Authors: Almohammadi Hanaa , Nasef Nehad , Al-Harbi Aziza , Saidy Khalid , Nour Islam
Published: November 2020

Objective This study aimed to assess the incidence and predictors of rebound in term and late-preterm infants with hemolytic hyperbilirubinemia postphototherapy.

Study Design A 4-year retrospective data analysis of neonates with hemolytic indirect hyperbilirubinemia admitted to the neonatal intensive care unit (NICU) of Medina Maternity and Children's Hospital was conducted. Bilirubin rebound was defined as the return of total serum bilirubin (TSB) to phototherapy threshold within 72 hours of postphototherapy.

Results Of 386 identified neonates; 44 (11%) experienced rebound. Neonates in the rebound group demonstrated significantly higher levels of peak TSB, TSB at discontinuation of phototherapy, and lower value of relative TSB (difference between TSB at phototherapy termination and the American Academy of Pediatrics [AAP] threshold for phototherapy at concurrent age) compared with nonrebound group (p-value: <0.001, <0.001, and 0.007, respectively). Lower value of relative TSB at stoppage of phototherapy was the single independent predictor for rebound hyperbilirubinemia by mutivariate regression (p < 0.001). A cut-off value for relative TSB at stoppage of phototherapy of 190 µmol/L had 98% sensitivity and 32% specificity to predict rebound hyperbilirubinemia.

Conclusion Relative TSB at phototherapy termination is the best predictor for postphototherapy rebound hyperbilirubinemia in neonates with hemolytic etiology.

Key Points
Wide Excision with Immediate Reconstruction of the Mandible Using Free Fibular Flap in Ameloblastoma of the Mandible—A Need of Time: Our Experience of 37 Cases
Authors: Saraiya Hemant A.
Published: November 2020

Background Ameloblastoma is a benign yet locally aggressive odontogenic tumor of the jaw with high recurrence rates. Despite many studies, the search is still on for the treatment approach which can render the acceptable recurrence rates with good functional and esthetic results.

Methods In this prospective study, we operated on 37 patients of mandibular ameloblastoma between 2009 and 2018. Two patients were treated with curettage and chemical sterilization of the cavity. Resection of a tumor with a 2-cm margin was performed in the rest of 35 patients. The mandibular defect was primarily reconstructed with the microvascular free fibular flap in 29 patients.

Results The follow-up ranged from 6 months to 7.7 years with a mean of 5.1 years. A tumor recurred within a year in all two patients (100%) treated with curettage. Out of 35 radical excisions, only one patient (2.85%) developed recurrence 3 years after the disease-free interval. Good mouth opening, intelligible speech, satisfactory lower jaw shape, and facial profiles were achieved in all 29 patients who were treated with primary free fibular flap.

Conclusion We prefer wide excision with 2-cm margins on each side of a tumor with the primary reconstruction of the mandible in all cases of mandibular ameloblastoma. The free fibular microvascular flap is our treatment of choice as all defects of the mandible can be reconstructed with the free fibular flap. Wide excision is the key to prevent a recurrence.
Return to Sport and Work after Randomization for Knee Distraction versus High Tibial Osteotomy: Is There a Difference?
Authors: Hoorntje Alexander , Kuijer P. Paul F. M. , Koenraadt Koen L. M. , Waterval-Witjes Suzanne , Kerkhoffs Gino M. M. J. , Mastbergen Simon C. , Marijnissen Anne C. A. , Jansen Mylène P. , van Geenen Rutger C. I.
Published: November 2020

Knee joint distraction (KJD) is a novel technique for relatively young knee osteoarthritis (OA) patients. With KJD, an external distraction device creates temporary total absence of contact between cartilage surfaces, which results in pain relief and possibly limits the progression of knee OA. Recently, KJD showed similar clinical outcomes compared with high tibial osteotomy (HTO). Yet, no comparative data exist regarding return to sport (RTS) and return to work (RTW) after KJD. Therefore, our aim was to compare RTS and RTW between KJD and HTO. We performed a cross-sectional follow-up study in patients <65 years who previously participated in a randomized controlled trial comparing KJD and HTO. Out of 62 eligible patients, 55 patients responded and 51 completed the questionnaire (16 KJDs and 35 HTOs) at 5-year follow-up. The primary outcome measures were the percentages of RTS and RTW. Secondary outcome measures included time to RTS/RTW, and pre- and postoperative Tegner's (higher is more active), and Work Osteoarthritis or Joint-Replacement Questionnaire (WORQ) scores (higher is better work ability). Patients' baseline characteristics did not differ. Total 1 year after KJD, 79% returned to sport versus 80% after HTO (not significant [n.s.]). RTS <6 months was 73 and 75%, respectively (n.s.). RTW 1 year after KJD was 94 versus 97% after HTO (n.s.), and 91 versus 87% <6 months (n.s.). The median Tegner's score decreased from 5.0 to 3.5 after KJD, and from 5.0 to 3.0 after HTO (n.s.). The mean WORQ score improvement was higher after HTO (16 ± 16) than after KJD (6 ± 13; p = 0.04). Thus, no differences were found for sport and work participation between KJD and HTO in our small, though first ever, cohort. Overall, these findings may support further investigation into KJD as a possible joint-preserving option for challenging “young” knee OA patients. The level of evidence is III.
Are Elevated Nicotine and Cotinine Levels Associated with Early Femoral Component Subsidence in Press-Fit, Primary Total Hip Arthroplasty?
Authors: Muffly Brian T. , Jacobs Cale A. , Duncan Stephen T.
Published: November 2020

Tobacco exposure negatively affects bone mineral density and early osseointegration of surgical implants. We sought to determine if elevated nicotine and/or cotinine levels prior to primary total hip arthroplasty (THA) are associated with early femoral component subsidence. We hypothesize that tobacco users will have higher rates of readmission/reoperation and increased radiographic subsidence. We conducted an institutional review of 75 patients (average age = 52.9 years; 55% females; body mass index = 31.3) who underwent THA from April 2017 to January 2018. Immediate postoperative radiographs were compared with those obtained at 2 to 6 weeks postoperatively to determine early femoral component subsidence. Of the 75 patients, 10 (13.3%) had early radiographic femoral component subsidence ≥ 2 mm. In this group, preoperative nicotine levels were significantly elevated (7.2 vs. 1.5ng/mL; p = 0.04), whereas preoperative cotinine levels did not statistically differ (108.3 vs. 33.8 ng/mL; p = 0.45). A significantly greater magnitude of subsidence was seen in those with elevated preoperative nicotine levels compared with those with normal levels (1.7 vs. 0.5 mm; p = 0.04). The mean time to radiographic follow-up was 2.6 weeks. Surgical approach, implant type, categorical variables, and patient readmission were not associated with ≥ 2 mm of early subsidence. There was a single reoperation for periprosthetic fracture, but none was related to instability from subsidence. Early femoral component subsidence was more prevalent in patients with elevated preoperative nicotine levels. Rates of readmission/reoperation at 90 days did not differ between those with and without elevated tobacco markers. Clinically relevant thresholds of preoperative nicotine and/or cotinine values are needed to better delineate appropriate surgical candidates to achieve optimal surgical outcomes.
Ex Vivo Ovine Model for Surgical and Microsurgical Training on Parotidectomy and Facial Nerve Reanimation: Proposal of Structured Training Program
Authors: Ghirelli Michael , Federici Gaia , Melchiorri Claudio , Malagoli Andrea , Presutti Livio , Fernandez Ignacio Javier
Published: November 2020

Introduction Facial nerve palsy has a great physical and psychological impact on patients, so the avoidance of facial nerve damage during surgery and its reanimation are important for Otolaryngologists and head and neck surgeons. The acquisition of anatomical knowledge and surgical training regarding the parotid surgery and facial nerve is mandatory, but not easy to achieve. Surgical simulation is a reliable alternative to the on-the-job learning. In the study, we tested an ex vivo animal model to obtain the basic and advanced skills of parotid gland surgery and facial nerve reconstruction/reanimation.

Materials and Methods A prospective cohort study has been conducted on ovine head and neck specimen. A junior resident, a senior resident, and an expert surgeon were involved in a step-by-step preplanned dissection, divided in macroscopic and microscopic. Each procedure was recorded and evaluated by an expert surgeon following an adapted rating scale.

Results A statistically significant improvement in terms of execution times and quality of the work was show in most of the surgical steps and for many quality items by the junior and senior residents, while the expert surgeon, as expected, did not show any improvement.

Discussion Our ex vivo ovine model provided the trainee with close-to-real tissues in term of elastic resistance and consistency, to learn the skills requested in a head and neck surgery, on a reproducible environment. It is mandatory to have a feedback, which focuses on the quality of the work through valid and reliable assessment of technical skills. The judgment parameters should be reproducible and focused on the specific surgical procedure. Some limitations to this study are present, such as anatomical differences between ovine and human and the limited number of study participants.

Conclusion This proposal of training program on the ex vivo ovine model for the acquisition of skills needed in head and neck surgery proved to be feasible, effective, repeatable, and cheap.
Leukopenia and Neutropenia at Birth and Sepsis in Preterm Neonates of <32 Weeks' Gestation
Authors: Shah Jyotsna , Balasubramaniam Tharshini , Yang Jie , Shah Prakesh S.
Published: November 2020

Objective This study aimed to evaluate associations between leukopenia or neutropenia at birth and risk of sepsis in very preterm neonates.

Study Design We conducted a retrospective unmatched cohort study of neonates of <32 weeks' gestation. Those with leukopenia (≤5,000/µL) were compared with a unmatched cohort without leukopenia. Comparisons were also made for patients with neutropenia and without neutropenia. The outcomes were early-onset sepsis, late-onset sepsis, and mortality.

Results We identified 271 neonates with leukopenia at birth and 271 without. Multivariable analyses identified higher odds of early-onset sepsis (adjusted odds ratio [AOR] = 4.85, 95% confidence interval [CI]: 1.29–18.20) in leukopenic neonates. Of neonates with leukopenia, 183 had both leukopenia and neutropenia and were associated with the highest odds of early-onset sepsis (AOR = 6.94, 95% CI: 1.77–27.15) compared with those with neither or with either alone.

Conclusion Leukopenia, neutropenia, and both leukopenia and neutropenia at birth were associated with early-onset sepsis in very preterm neonates.

Key Points
Reactive fluxes delivered by plasma jets to conductive dielectric surfaces during multiple reflections of ionization waves
Authors: Babaeva Natalia Yu. , Naidis George V.
Published: November 2020

In this paper, we report results from the computational study of the intersection of the atmospheric pressure plasma jet with a dielectric surface having high conductivity and high dielectric constant. In this case, multiple reflections of the ionization wave (IW) between the jet tube and the surface are observed. We consider the mixture of helium with a small percentage of oxygen (He/O2 = 99.8/0.2), which flows through the jet tube into the ambient humid room air (N2/O2/H2O = 79.5/20/0.5). We evaluate the production and delivery of main ions and reactive oxygen and nitrogen species, which are important for applications in biomedicine. The fluxes and fluences of these species to the dielectric surface are recorded during a single plasma jet pulse of negative polarity. We show that the electron density behind the IW front increases with each passage of the IW between the tube and the surface. With the forward, reflected, and secondary forward IW, there is an essential increase of ions and radicals behind the IW front. The highest increase of radicals and their fluxes is observed after the secondary forward wave bridges the gap and touches the surface.
Universal upper estimate for prediction errors under moderate model uncertainty
Authors: Kaszás Bálint , Haller George
Published: November 2020

We derive universal upper estimates for model prediction error under moderate but otherwise unknown model uncertainty. Our estimates give upper bounds on the leading-order trajectory uncertainty arising along model trajectories, solely as functions of the invariants of the known Cauchy–Green strain tensor of the model. Our bounds turn out to be optimal, which means that they cannot be improved for general systems. The quantity relating the leading-order trajectory-uncertainty to the model uncertainty is the model sensitivity (MS), which we find to be a useful tool for a quick global assessment of the impact of modeling uncertainties in various domains of the phase space. By examining the expectation that finite-time Lyapunov exponents capture sensitivity to modeling errors, we show that this does not generally follow. However, we find that certain important features of the finite-time Lyapunov exponent persist in the MS field.
Discrimination of sunflower seeds using multispectral and texture dataset in combination with region selection and supervised classification methods
Authors: Bantan Rashad A. R. , Ali Aqib , Naeem Samreen , Jamal Farrukh , Elgarhy Mohammed , Chesneau Christophe
Published: November 2020

The purpose of this study is to discriminate sunflower seeds with the help of a dataset having spectral and textural features. The production of crop based on seed purity and quality other hand sunflower seed used for oil content worldwide. In this regard, the foundation of a dataset categorizes sunflower seed varieties (Syngenta CG, HS360, S278, HS30, Armani, and High Sun 33), which were acquired from the agricultural farms of The Islamia University of Bahawalpur, Pakistan, into six classes. For preprocessing, a new region-oriented seed-based segmentation was deployed for the automatic selection of regions and extraction of 53 multi-features from each region, while 11 optimized fused multi-features were selected using the chi-square feature selection technique. For discrimination, four supervised classifiers, namely, deep learning J4, support vector machine, random committee, and Bayes net, were employed to optimize the multi-feature dataset. We observe very promising accuracies of 98.2%, 97.5%, 96.6%, and 94.8%, respectively, when the size of a region is (180 × 180).
Polarization of acetonitrile under thermal fields via non-equilibrium molecular dynamics simulations
Authors: Gittus Oliver R. , Albella Pablo , Bresme Fernando
Published: November 2020

We show that thermal gradients polarize liquid and supercritical acetonitrile. The polarization results in a stationary electrostatic potential that builds up between hot and cold regions. The strength of the field increases with the static dielectric constant or with decreasing temperature. At near standard conditions, the thermal polarization coefficient is ∼−0.6 mV/K, making it possible to induce significant electrostatic fields, ∼103 V/m, with thermal gradients ∼1 K/μm. At supercritical conditions, ∼600 K and 0.249 g/cm3 (the critical isochore), the electrostatic field is of the same order, despite the low dielectric constant of the fluid. In this case, the electrostatic field is determined by the enhanced rotational diffusion of the molecules and stronger cross-coupling between heat and polarization fluxes. We show that the coupling between the heat and polarization fluxes influences the thermal conductivity of acetonitrile, which becomes a worse heat conductor. For the thermodynamic states investigated in this work, the thermal polarization effect leads to a ∼2%–5% reduction in thermal conductivity.
Complementary growth of 2D transition metal dichalcogenide semiconductors on metal oxide interfaces
Authors: Wickramasinghe Thushan E. , Jensen Gregory , Thorat Ruhi , Lindquist Miles , Aleithan Shrouq H. , Stinaff Eric
Published: November 2020

A chemical vapor deposition (CVD) growth model is presented for a technique resulting in naturally formed 2D transition metal dichalcogenide (TMD)-based metal-oxide-semiconductor structures. The process is based on a standard CVD reaction involving a chalcogen and transition metal oxide-based precursor. Here however, a thin metal oxide layer formed on lithographically defined contacts composed of pure bulk transition metal serves as the precursor. The chalcogen reacts with the metal oxide, leading to the growth of highly crystalline films, which display strong luminescence, monolayer Raman signatures, and relatively large crystal domains. Raman spectroscopy and cross-sectional SEM studies provide insight into the characteristics of the metal oxide and its effect on the TMD growth. The TMD material migrates outward along the substrate while remaining connected to the lithographically defined contacts, offering a scalable path for producing as-grown, naturally contacted, two-dimensional material-based devices.
Strength of porous α-SiO2 in a shock loaded environment: Calibration via Richtmyer–Meshkov instability and validation via Mach lens
Authors: Hudspeth Matthew , Olles Joseph , Mandal Anirban , Williams James , Root Seth , Vogler Tracy
Published: November 2020

The strength of brittle porous media is of concern in numerous applications, for example, earth penetration, crater formation, and blast loading. Thus, it is of importance to possess techniques that allow for constitutive model calibration within the laboratory setting. The goal of the current work is to demonstrate an experimental technique allowing for strength assessment of porous media subjected to shock loading, which can be implemented into pressure-dependent yield surfaces within numerical simulation schemes. As a case study, the deviatoric response of distended α-SiO2 has been captured in a tamped Richtmyer–Meshkov instability (RMI) environment at a pressure regime of 4–10 GPa. Hydrocode simulations were used to interpret RMI experimental data, and a resulting pressure-dependent yield surface akin to the often employed modified Drucker–Prager model was calibrated. Simulations indicate that the resulting jet length generated by the RMI is sensitive to the porous media strength, thereby providing a feasible experimental platform capable of capturing the pressurized granular deviatoric response. Furthermore, in efforts to validate the RMI-calibrated strength model, a set of Mach-lens experiments was performed and simulated with the calibrated pressure-dependent yield surface. Excellent agreement between the resulting Mach-lens length in experiment and simulation provides additional confidence to the RMI yield-surface calibration scheme.
Tuning the spontaneous exchange bias effect with Ba to Sr partial substitution in La1.5(Sr0.5−xBax)CoMnO6
Authors: Boldrin M. , Silva A. G. , Coutrim L. T. , Jesus J. R. , Macchiutti C. , Bittar E. M. , Bufaiçal L.
Published: November 2020

The spontaneous exchange bias (SEB) effect is a remarkable phenomenon recently observed in some reentrant spin-glass materials. Here, we investigate the SEB in La1.5(Sr0.5−xBax)CoMnO6 double-perovskites, a system with multifarious magnetic phases for which a notable increase in the exchange bias field is observed for intermediate Sr/Ba concentrations. The Ba to Sr substitution leads to the enhancement of the crystal lattice, which is accompanied by the increase in both the effective magnetic moment (μeff) and the antiferromagnetic (AFM) transition temperature that is observed below the ferromagnetic ordering. Such an increase is likely related to the increased fraction of Co3+ in the high spin configuration, leading to the enhancement of the Co3+–O–Mn4+ AFM phase and the reduction in the uncompensation of the AFM coupling between Co and Mn. The combined effect of the increased μeff and AFM phase plausibly explains the changes in the SEB effect.
III–V lasers selectively grown on (001) silicon
Authors: Han Yu , Lau Kei May
Published: November 2020

Epitaxial growth of III–V lasers on the (001) Si platform is emerging as the ultimate integration strategy for low-cost, energy-efficient, and wafer-scale photonic integrated circuits. As the performance of laser diodes grown on III–V/Si compliant substrates develops toward commercialization, the issue of light interfacing between epitaxial III–V lasers and Si-based waveguides is becoming increasingly pressing. As an alternative, selective area growth produces buffer-less III–V lasers on Si and thereby intrinsically promotes efficient light coupling with Si-photonics. As the dimension of the selectively grown dislocation-free III–V crystals is often limited at the sub-wavelength scale, the main challenge lies at the realization of electrically driven lasers and, specifically, at how to pattern the metal contacts without inducing large optical absorption loss. In this Perspective, we provide a brief overview of the state-of-the-art III–V lasers selectively grown on the (001) Si platform and discuss the outlook of this integration approach with an emphasis on the prospects of achieving electrically driven devices. We focus on the unique advantages offered by selective hetero-epitaxy as well as the challenges and potential solutions toward practical applications.
Is microfluidics the “assembly line” for CRISPR-Cas9 gene-editing?
Authors: Ahmadi Fatemeh , Quach Angela B. V. , Shih Steve C. C.
Published: November 2020

Acclaimed as one of the biggest scientific breakthroughs, the technology of CRISPR has brought significant improvement in the biotechnological spectrum—from editing genetic defects in diseases for gene therapy to modifying organisms for the production of biofuels. Since its inception, the CRISPR-Cas9 system has become easier and more versatile to use. Many variants have been found, giving the CRISPR toolkit a great range that includes the activation and repression of genes aside from the previously known knockout and knockin of genes. Here, in this Perspective, we describe efforts on automating the gene-editing workflow, with particular emphasis given on the use of microfluidic technology. We discuss how automation can address the limitations of gene-editing and how the marriage between microfluidics and gene-editing will expand the application space of CRISPR.
Rotational constraint contributes to collective cell durotaxis
Authors: Liu Yang , Cheng Jiwen , Yang Hui , Xu Guang-Kui
Published: November 2020

Directed cell migration following the gradients of extracellular matrix stiffness, termed durotaxis, plays an essential role in development, wound healing, and cancer invasion. Here, we develop a cytoskeleton-based mechanical model to study the migration modes of both isolated cells and cell clusters on gradient substrates. We find that collective cell durotaxis is attributed to the geometrical restriction of cell rotation by neighboring cells, leading to a different migration mode from isolated cells. Moreover, isolated cells are able to undergo directed migration on a soft substrate with relatively high stiffness gradients. In addition, collective cell durotaxis is far more efficient than single-cell durotaxis. The migration mode is determined by the competition between the difference of traction forces between the cell-substrate interface and the random force from microenvironments. This study indicates that isolated cells are more sensitive to environmental fluctuations, whereas cell clusters can counteract the effects of fluctuations by cell–cell interactions.
How coronavirus survives for days on surfaces
Authors: Bhardwaj Rajneesh , Agrawal Amit
Published: November 2020

Our previous study [R. Bhardwaj and A. Agrawal, “Likelihood of survival of coronavirus in a respiratory droplet deposited on a solid surface,” Phys. Fluids 32, 061704 (2020)] showed that the drying time of typical respiratory droplets is on the order of seconds, while the survival time of the coronavirus on different surfaces was reported to be on the order of hours in recent experiments. We attribute the long survival time of the coronavirus on a surface to the slow evaporation of a thin nanometer liquid film remaining after the evaporation of the bulk droplet. Accordingly, we employ a computational model for a thin film in which the evaporating mass rate is a function of disjoining and Laplace pressures inside the film. The model shows a strong dependence on the initial thickness of the film and suggests that the drying time of this nanometric film is on the order of hours, consistent with the survival time of the coronavirus on a surface, seen in published experiments. We briefly examine the change in the drying time as a function of the contact angle and type of surface. The computed time-varying film thickness or volume qualitatively agrees with the measured decay of the coronavirus titer on different surfaces. The present work provides insights on why coronavirus survival is on the order of hours or days on a solid surface under ambient conditions.
Social interactions, roost usage and notes on the breeding system of the chocolate wattled bat (Chalinolobus morio) in south-east Queensland, Australia
Authors: Thomson Bruce G.
Published: November 2020

Little is known about the social behaviour of roosting insectivorous bats in Australia. Interactions between individuals and movements between multiple roosts at a building maternity site of the chocolate wattled bat (Chalinolobus morio) were examined using video observation and Passive Integrated Transponder (PIT) tagging, respectively. Bats of both sexes were seen to allogroom, which involved pairs of individuals simultaneously grooming each other around the face. This is the first occurrence of allogrooming reported between male vespertilionids, globally. In total, 366 bats were PIT tagged and analysis of movements revealed that bats exhibited a fission–fusion pattern of roost usage with sufficient switching among nearby roosts, such that all individuals were potentially able to associate and interact over a period of 150–200 days. Rates of roost fidelity varied markedly from 1 to 7.2 days of continuous occupancy of roosts, with females exhibiting slightly higher overall levels of fidelity over the nine-month monitoring period. The information gained from this study, when combined with results from other research, provides a sufficient basis for the description of the apparent breeding system for this species, where both males and females at the summer maternity roost are natally philopatric and mating takes place over winter in an expanded gene pool, comprising individuals that have dispersed from multiple summer maternity roosts.
AI, visual imagery, and a case study on the challenges posed by human intelligence tests
Authors: Kunda Maithilee
Published: November 2020

Observations abound about the power of visual imagery in human intelligence, from how Nobel prize-winning physicists make their discoveries to how children understand bedtime stories. These observations raise an important question for cognitive science, which is, what are the computations taking place in someone’s mind when they use visual imagery? Answering this question is not easy and will require much continued research across the multiple disciplines of cognitive science. Here, we focus on a related and more circumscribed question from the perspective of artificial intelligence (AI): If you have an intelligent agent that uses visual imagery-based knowledge representations and reasoning operations, then what kinds of problem solving might be possible, and how would such problem solving work? We highlight recent progress in AI toward answering these questions in the domain of visuospatial reasoning, looking at a case study of how imagery-based artificial agents can solve visuospatial intelligence tests. In particular, we first examine several variations of imagery-based knowledge representations and problem-solving strategies that are sufficient for solving problems from the Raven’s Progressive Matrices intelligence test. We then look at how artificial agents, instead of being designed manually by AI researchers, might learn portions of their own knowledge and reasoning procedures from experience, including learning visuospatial domain knowledge, learning and generalizing problem-solving strategies, and learning the actual definition of the task in the first place.
Rational thoughts in neural codes
Authors: Wu Zhengwei , Kwon Minhae , Daptardar Saurabh , Schrater Paul , Pitkow Xaq
Published: November 2020

Complex behaviors are often driven by an internal model, which integrates sensory information over time and facilitates long-term planning to reach subjective goals. A fundamental challenge in neuroscience is, How can we use behavior and neural activity to understand this internal model and its dynamic latent variables? Here we interpret behavioral data by assuming an agent behaves rationally—that is, it takes actions that optimize its subjective reward according to its understanding of the task and its relevant causal variables. We apply a method, inverse rational control (IRC), to learn an agent’s internal model and reward function by maximizing the likelihood of its measured sensory observations and actions. This thereby extracts rational and interpretable thoughts of the agent from its behavior. We also provide a framework for interpreting encoding, recoding, and decoding of neural data in light of this rational model for behavior. When applied to behavioral and neural data from simulated agents performing suboptimally on a naturalistic foraging task, this method successfully recovers their internal model and reward function, as well as the Markovian computational dynamics within the neural manifold that represent the task. This work lays a foundation for discovering how the brain represents and computes with dynamic latent variables.
Representations of common event structure in medial temporal lobe and frontoparietal cortex support efficient inference
Authors: Morton Neal W , Schlichting Margaret L. , Preston Alison R.
Published: November 2020

Prior work has shown that the brain represents memories within a cognitive map that supports inference about connections between individual related events. Real-world adaptive behavior is also supported by recognizing common structure among numerous distinct contexts; for example, based on prior experience with restaurants, when visiting a new restaurant one can expect to first get a table, then order, eat, and finally pay the bill. We used a neurocomputational approach to examine how the brain extracts and uses abstract representations of common structure to support novel decisions. Participants learned image pairs (AB, BC) drawn from distinct triads (ABC) that shared the same internal structure and were then tested on their ability to infer indirect (AC) associations. We found that hippocampal and frontoparietal regions formed abstract representations that coded cross-triad relationships with a common geometric structure. Critically, such common representational geometries were formed despite the lack of explicit reinforcement to do so. Furthermore, we found that representations in parahippocampal cortex are hierarchical, reflecting both cross-triad relationships and distinctions between triads. We propose that representations with common geometric structure provide a vector space that codes inferred item relationships with a direction vector that is consistent across triads, thus supporting faster inference. Using computational modeling of response time data, we found evidence for dissociable vector-based retrieval and pattern-completion processes that contribute to successful inference. Moreover, we found evidence that these processes are mediated by distinct regions, with pattern completion supported by hippocampus and vector-based retrieval supported by parahippocampal cortex and lateral parietal cortex.
A new sea-level record for the Neogene/Quaternary boundary reveals transition to a more stable East Antarctic Ice Sheet
Authors: Jakob Kim A. , Wilson Paul A. , Pross Jörg , Ezard Thomas H. G. , Fiebig Jens , Repschläger Janne , Friedrich Oliver
Published: November 2020

Significance

We studied the response of global ice volume/sea level to climate forcing from ∼2.75 to 2.4 Ma, when atmospheric CO
2
levels last lay in a range similar to the last two centuries. Our data reveal clear cycles in global sea level largely driven by the growth/decay of Northern Hemisphere ice sheets. Peak sea levels suggest melting of East Antarctic land ice prior to ∼2.53 Ma. Thereafter, glacial and interglacial sea levels are distinctly lower than before, suggesting that the growth of larger Northern Hemisphere ice sheets lowered sea level globally and acted to stabilize the East Antarctic Ice Sheet by limiting its exposure to warm ocean waters. Our findings provide a framework to help understand ice-volume variability under warmer-than-preindustrial climates.
The Ig heavy chain protein but not its message controls early B cell development
Authors: Aslam Muhammad Assad , Alemdehy Mir Farshid , Hao Bingtao , Krijger Peter H. L. , Pritchard Colin E. J. , de Rink Iris , Muhaimin Fitriari Izzatunnisa , Nurzijah Ika , van Baalen Martijn , Kerkhoven Ron M. , van den Berk Paul C. M. , Skok Jane A. , Jacobs Heinz
Published: November 2020

Significance

Immunoglobulin heavy chain checkpoint (IgHCC) is a critical step during early B cell development. The role of immunoglobulin heavy chain (IgHC) at this step is well established. However, with the expanding knowledge of RNA in regulating central biological processes, there could be a noncoding contribution of IgHC mRNA (
IgHR
) in controlling the IgHCC. Here, we generated a novel mouse model that enabled us to determine a potential role of
IgHR
in the IgHCC, independent of IgHC signaling. Our data indicate that
IgHR
has no role in IgHCC and the latter is predominantly controlled by IgHC, as proposed earlier. Furthermore, this study highlights the sensitivity of progenitor B cells to low amounts of IgHC.