bluuebunny/crossref_metadata_2025 huggingface dataset:
Universal spectral features of different classes of random-diffusivity processes
Authors: Sposini Vittoria , Grebenkov Denis S , Metzler Ralf , Oshanin Gleb , Seno Flavio
Published: May 2020

Stochastic models based on random diffusivities, such as the diffusing-diffusivity approach, are popular concepts for the description of non-Gaussian diffusion in heterogeneous media. Studies of these models typically focus on the moments and the displacement probability density function. Here we develop the complementary power spectral description for a broad class of random-diffusivity processes. In our approach we cater for typical single particle tracking data in which a small number of trajectories with finite duration are garnered. Apart from the diffusing-diffusivity model we study a range of previously unconsidered random-diffusivity processes, for which we obtain exact forms of the probability density function. These new processes are different versions of jump processes as well as functionals of Brownian motion. The resulting behaviour subtly depends on the specific model details. Thus, the central part of the probability density function may be Gaussian or non-Gaussian, and the tails may assume Gaussian, exponential, log-normal, or even power-law forms. For all these models we derive analytically the moment-generating function for the single-trajectory power spectral density. We establish the generic 1/f
2-scaling of the power spectral density as function of frequency in all cases. Moreover, we establish the probability density for the amplitudes of the random power spectral density of individual trajectories. The latter functions reflect the very specific properties of the different random-diffusivity models considered here. Our exact results are in excellent agreement with extensive numerical simulations.
Rabi oscillation study of strong coupling in a plasmonic nanocavity
Authors: Huang Yuming , Wu Fan , Yu Li
Published: May 2020

Strong interaction between emitters and plasmonic nanocavity has various applications in quantum fields at room temperature. As Rabi oscillation gives the direct proof to the energy exchange in strong coupling, it is more intuitive and necessary to analyze the interaction in time domain. In this paper, we give the Rabi oscillation in a high-dissipation plasmonic nanocavity by using full-quantum method and draw a new strong coupling criterion about mode volume which provides a significant guidance in plasmonic nanocavitys nanofabrication. Moreover, we reveal the relation between Rabi oscillation and Rabi splitting, which is beneficial for exploring emitter–plasmon hybrid systems time-domain property through frequency-domain response. An emitter–hexagon hybrid system with ultrasmall mode volume is designed to verify our theory. The numerical simulation shows good agreements with our theoretical results. Our work has applications in quantum information and quantum computing in the future.
Cyclone Fani: the tug-of-war between regional warming and anthropogenic aerosol effects
Authors: Zhao Lin , Simon Wang S-Y , Becker Emily , Yoon Jin-Ho , Mukherjee Avik
Published: May 2020

Before Cyclone Amphan took place in 2020, Cyclone Fani (May 2019) is the strongest pre-monsoon cyclone in the Bay of Bengal (BOB) since 1991, killing 90 people in eastern India and Bangladesh while causing US$1.81 billion of damages. Fani developed during a period of high concentration of anthropogenic aerosols in the BOB with abnormally high sea surface temperature (SST), thereby presenting an opportunity to understand the compound effects of atmospheric aerosols and regional climate warming on a tropical cyclone. A quantitative attribution analysis was conducted using the Weather Research and Forecasting model with chemistry (WRF-Chem) run at the convection-permitting (4 km) grid spacing, accompanied by an ensemble of coarser-resolution simulations to quantify the uncertainty. The removal of post-1990 trends in the tropospheric variables and SST from WRF-Chem’s initial conditions (IC) and boundary conditions (BC, including the lateral and lower boundary conditions) resulted in a reduction of cyclone precipitation by about 51% during the 5 d of April 28-May 2. The removal of tropospheric warming shows approximately twice as strong an effect on Fani (39% reduction in precipitation) as that of SST warming (22% reduction). When aerosol’s direct and indirect effects were removed from the simulations, i.e., no aerosol influence on radiation and cloud microphysics, Fani initially strengthened but later weakened, as measured by geopotential height and precipitation amounts. These results suggest that aerosol and its interaction with the atmosphere acted to mitigate the strengthening effect of anthropogenic warming on Fani, but was not strong enough to entirely counteract it. Although the ensemble of coarser simulations appears to overestimate Cyclone Fani in terms of precipitation, the direction of the effects is in agreement with that obtained from the 4 km simulations. Given the increasing anthropogenic aerosols in the BOB, future attribution studies using more sophisticated dynamical aerosol models on BOB tropical cyclones are urged.
Green space structures and schizophrenia incidence in Taiwan: is there an association?
Authors: Chang Hao-Ting , Wu Chih-Da , Wang Jung-Der , Chen Po-See , Wang Ying-Jan , Su Huey-Jen
Published: May 2020

A growing body of research indicates overall greenness offers potential psychological benefits. However, few studies have explored green space structures and their potential association with mental disorders. The aim of this study was to determine the existence of such an association. From two million randomly sampled people in Taiwan’s National Health Insurance Research Database, we selected 3823 patients that received a first-time diagnosis of schizophrenia from 2005–2016. Moreover, we used a geographic information system and a landscape index to quantify three characteristics of green space structures including area and edge, shape, and proximity. Additionally, we collected the normalized difference vegetation index and enhanced vegetation index data to reconfirm the association between overall greenness and schizophrenia incidence. We used the indices to determine individuals’ exposure according to their residential township. Spearman’s correlation analysis was conducted to select variables by considering their collinearity. Cox proportional-hazards models were applied to assess the relationship between green space exposure and schizophrenia incidence following adjustment for potential confounders, such as air pollution (NO2, SO2, ozone, and PM10), temperature, precipitation, and socioeconomic status, which are risk factors. We found a negative association between most green space structures indices and schizophrenia incidence. Our findings suggest that for green spaces, a larger mean patch area and edge density, higher complex (higher perimeter–area ratio), and greater proximity (higher contiguity index, aggregation index, and contagion index), may reduce the risk of schizophrenia. A sensitivity test and subgroup analysis revealed similar results.
Quantum metric statistics for random-matrix families
Authors: Berry M V , Shukla Pragya
Published: May 2020

The quantum metric tensor G

ij
for parameterised families of quantum states, in particular the trace G = trG

ij
, depends on the symmetry of the system (e.g. time-reversal), and the dimension N of the underlying matrices. Modelling the families by the stationary Gaussian ensembles of random-matrix, theory, we calculate the probability distribution of G, exactly for N = 2, and approximately for N = 3 and N → ∞. Codimension arguments establish the scalings of the distributions near the singularities at G → ∞ and G = 0, near which asymptotics gives the explicit analytic behaviour. Numerical simulations support the theory.
Bipolar photoresponse ultraviolet photodetectors based on ZnO nanowires
Authors: Zarezadeh E , Ghorbani A
Published: May 2020

A comparative study on the photoresponse of zinc oxide nanowires in direct-current (DC) and alternating-current (AC) domains is presented. Zinc oxide ultraviolet photodetectors exhibit positive photoconductivity in DC domain which means that the resistance decreases upon illumination. However, in the frequency domain, zinc oxide nanowires exhibit a solid frequency-modulated response to the ultraviolet illumination leading to a tunable photoconductivity. It is shown that in AC domain the photoresponse of zinc oxide nanowires can be finely adjusted from the positive photoconductivity (resistance decrement) to negative photoconductivity (resistance increment) simply by tuning the driving frequency. Frequency-modulated photoresponse of zinc oxide nanostructures provides an exclusive platform for the realization of dual-response or bipolar photoresponse ultraviolet photodetectors which could be of high technological importance. The zinc oxide nanowires exhibit a responsivity of +180 mA W−1 to the ultraviolet illumination in the DC mode. The nanowires show an almost equal but negative responsivity in the AC domain. Practical implication of the bipolar ultraviolet photodetectors based on ZnO nanowires is presented.
Fast Learning Through Deep Multi-Net CNN Model For Violence Recognition In Video Surveillance
Authors: Mumtaz Aqib , Bux Sargano Allah , Habib Zulfiqar
Published: May 2020

The violence detection is mostly achieved through handcrafted feature descriptors, while some researchers have also employed deep learning-based representation models for violent activity recognition. Deep learning-based models have achieved encouraging results for fight activity recognition on benchmark data sets such as hockey and movies. However, these models have limitations in learning discriminating features for violence activity classification with abrupt camera motion. This research work investigated deep representation models using transfer learning for handling the issue of abrupt camera motion. Consequently, a novel deep multi-net (DMN) architecture based on AlexNet and GoogleNet is proposed for violence detection in videos. AlexNet and GoogleNet are top-ranked pre-trained models for image classification with distinct pre-learnt potential features. The fusion of these models can yield superior performance. The proposed DMN unleashed the integrated potential by concurrently coalescing both networks. The results confirmed that DMN outperformed state-of-the-art methods by learning finest discriminating features and achieved 99.82% and 100% accuracy on hockey and movies data sets, respectively. Moreover, DMN has faster learning capability i.e. 1.33 and 2.28 times faster than AlexNet and GoogleNet, which makes it an effective learning architecture on images and videos.
Protecting the outside: biological tools to manipulate the skin microbiota
Authors: O'Sullivan Julie N , Rea Mary C , Hill Colin , Ross R Paul
Published: May 2020

Interest surrounding the role that skin microbes play in various aspects of human health has recently experienced a timely surge, particularly among researchers, clinicians and consumer-focused industries. The world is now approaching a post-antibiotic era where conventional antibacterial therapeutics have shown a loss in effectiveness due to overuse, leading to the looming antibiotic resistance crisis. The increasing threat posed by antibiotic resistance is compounded by an inadequate discovery rate of new antibiotics and has, in turn, resulted in global interest for alternative solutions. Recent studies have demonstrated that imbalances in skin microbiota are associated with assorted skin diseases and infections. Specifically, restoration of this ecosystem imbalance results in an alleviation of symptoms, achieved simply by applying bacteria normally found in abundance on healthy skin to the skin of those deficient in beneficial bacteria. The aim of this review is to discuss the currently available literature on biological tools that have the potential to manipulate the skin microbiota, with particular focus on bacteriocins, phage therapy, antibiotics, probiotics and targets of the gut-skin axis. This review will also address how the skin microbiota protects humans from invading pathogens in the external environment while discussing novel strategies to manipulate the skin microbiota to avoid and/or treat various disease states.
From Montserrat to Settler-Colonial Australia: the Intersecting Histories of Caribbean Slave-owning Families, Transported British Radicals, and Indigenous Peoples
Authors: Curthoys Ann
Published: May 2020

When the British government abolished slavery in the Caribbean and compensated the slave-owners, some of the beneficiaries and/or their children and grandchildren went to Australia to make a new life and if possible a new fortune. This essay traces the history of one such family, the Shiells of Montserrat, alongside two other contemporaneous histories – that of Yorkshire radical and convict, John Burkinshaw, and his family, into which one of the Shiells married, and that of the several Indigenous communities these families encountered. Through the experiences of these disparate and intersecting family groups, we can gain insight into both the lived experience and the wider imperial context of the expansion of Australian settler colonialism.
Variational analysis of the discontinuous Galerkin time-stepping method for parabolic equations
Authors: Saito Norikazu
Published: May 2020

The discontinuous Galerkin (DG) time-stepping method applied to abstract evolution equation of parabolic type is studied using a variational approach. We establish the inf-sup condition or Babuška–Brezzi condition for the DG bilinear form. Then, a nearly best approximation property and a nearly symmetric error estimate are obtained as corollaries. Moreover, the optimal order error estimates under appropriate regularity assumption on the solution are derived as direct applications of the standard interpolation error estimates. Our method of analysis is new for the DG time-stepping method; it differs from previous works by which the method is formulated as the one-step method. We apply our abstract results to the finite element approximation of a second-order parabolic equation with space-time variable coefficient functions in a polyhedral domain, and derive the optimal order error estimates in several norms.
Economic evaluations of big data analytics for clinical decision-making: a scoping review
Authors: Bakker Lytske , Aarts Jos , Uyl-de Groot Carin , Redekop William
Published: May 2020

Objective

Much has been invested in big data analytics to improve health and reduce costs. However, it is unknown whether these investments have achieved the desired goals. We performed a scoping review to determine the health and economic impact of big data analytics for clinical decision-making.

Materials and Methods

We searched Medline, Embase, Web of Science and the National Health Services Economic Evaluations Database for relevant articles. We included peer-reviewed papers that report the health economic impact of analytics that assist clinical decision-making. We extracted the economic methods and estimated impact and also assessed the quality of the methods used. In addition, we estimated how many studies assessed “big data analytics” based on a broad definition of this term.

Results

The search yielded 12 133 papers but only 71 studies fulfilled all eligibility criteria. Only a few papers were full economic evaluations; many were performed during development. Papers frequently reported savings for healthcare payers but only 20% also included costs of analytics. Twenty studies examined “big data analytics” and only 7 reported both cost-savings and better outcomes.

Discussion

The promised potential of big data is not yet reflected in the literature, partly since only a few full and properly performed economic evaluations have been published. This and the lack of a clear definition of “big data” limit policy makers and healthcare professionals from determining which big data initiatives are worth implementing.
Optimization of Nitrogen Fertilizer Application Enhances Biocontrol Function and Net Income
Authors: Wang Leyun , Gao Feng , Reddy Gadi V P , Zhao Zihua
Published: May 2020

The intensive use of nitrogen fertilizer has been a common approach for pursuing higher crop yields. However, the ecological effects of such use on the tritrophic interactions (crop–insect pest–natural enemy) and on the ecological and economic benefits of such use are poorly understood. Here, we investigated the effects of low, medium, and high levels of nitrogen fertilizer inputs (70, 140, and 280 kg/ha/yr) on cereal aphid (Sitobion avenae Fabricius [Hemiptera: Aphididae], Schizaphis graminum Rondani [Hemiptera: Aphididae], and Rhopalosiphum padi L. [Hemiptera: Aphididae]) abundance, primary parasitism rates, crop yield, and net income in winter wheat (Triticum aestivum [Poales: Poaceae] cv. Zhou 22) for 2 yr. A higher input of nitrogen fertilizer significantly enhanced the abundance of cereal aphids, while their primary parasitism rates (26.9 ± 3.5% in 2018 and 24.9 ± 4.5% in 2019) were highest at the medium nitrogen level. The performance of participants in the wheat–aphids–parasitoids system was likewise mediated by the nitrogen fertilizers. Meanwhile, wheat yield significantly increased with moderate increases in the nitrogen level, although overuse of nitrogen fertilizer did not significantly further enhance wheat yield. Finally, we found either low or overuse of nitrogen fertilizers resulted in lower net income than did medium nitrogen fertilization. These results demonstrate the need to reevaluate and adjust fertilizer use to optimize the eco-economic and sustainable management of agroecosystems.
Detection of Asian Citrus Psyllid (Hemiptera: Psyllidae) in Ethiopia: A New Haplotype and its Implication to the Proliferation of Huanglongbing
Authors: Ajene Inusa J , Khamis Fathiya , Ballo Shifa , Pietersen Gerhard , van Asch Barbara , Seid Nurhussen , Azerefegne Ferdu , Ekesi Sunday , Mohamed Samira
Published: May 2020

Diaphorina citri Kuwayama, also known as the Asian citrus psyllid, is a pest of citrus known for its transmission of Candidatus Liberibacter asiaticus (Ca. L. asiaticus), the causal bacterium of Huanglongbing. The African citrus triozid Trioza erytreae (Del Guercio) (Hemiptera: Triozidae) has been the putative vector of Candidatus Liberibacter africanus (Ca. L. africanus) which causes the African citrus greening disease, until the recent detection of D. citri on the continent. Following reports of D. citri in Kenya and Tanzania, we surveyed citrus plants to establish the presence/absence of D. citri in Ethiopia in citrus-growing regions ranging from 900 to 2,460 m above sea level (masl). Diaphorina citri adults were detected in five of the surveyed sites in Ethiopia. Adult insects encountered were collected using an aspirator and stored in 97% ethanol. The mitochondrial cytochrome oxidase 1 (mt COI) gene of the collected insects was amplified using LepF1/LepR1 primers, and sequences obtained showed low variation, which fell within the acceptable range of species. BLAST was used to query the sequences obtained, and all the sequences linked to D. citri accessions that are available in GenBank. The analysis of the sequences revealed a new haplotype of the species that differs from haplotypes previously reported. Phylogenetic relationships of our samples and other D. citri reference sequences was inferred using the Maximum-likelihood method. Monophyly was observed between the samples and the publicly available sequences from global accessions. This is the first report of the presence of D. citri in Ethiopia.
Surgical approach and treatment for the orifice of a pyriform sinus fistula: a case report and literature review
Authors: Tatekawa Yukihiro
Published: May 2020

A 4-year-old girl underwent an open-neck surgical procedure for a recurrent pyriform sinus fistula (PSF). A catheter could not be inserted through the endoscope into the opening of the fistula. An open-neck surgical procedure with coring out of the fistula stained with a dye revealed that the fistula was missed near the upper lobe of the left thyroid. A guide wire was successfully inserted via the endoscope into the fistula, and the wire was gripped with forceps under fluoroscopic guidance and removed. As a modification of the surgical approach and treatment for the orifice of the PSF, a catheter was exchanged through the guide wire, and a nylon thread was passed into the catheter. The tip of the nylon thread from the oral side was fastened and fixed to a gauze ball. After removing the nylon thread, the orifice of the sinus fistula was recognized and sutured. She was discharged uneventfully and has done well without a postoperative recurrence for 12 months.
The Diachronic Spanish Sonnet Corpus: TEI and linked open data encoding, data distribution, and metrical findings
Authors: Ruiz Fabo Pablo , Bermúdez Sabel Helena , Martínez Cantón Clara , González-Blanco Elena
Published: May 2020

How has the sonnet form in Spanish evolved over the centuries? What is the distribution of metrical patterns and combinations thereof, considering diachronic, geographical, and social factors? What rhyme schemes are favoured in different periods and regions? How is enjambment distributed within the sonnet? Providing quantitative answers to such questions requires a corpus spanning several centuries, annotated for the relevant literary features and containing author metadata. The absence of appropriate digital resources to undertake a macroanalytic study of the evolution of the sonnet in Spanish led us to create the Diachronic Spanish Sonnet Corpus. This article presents how the corpus was designed for providing quantitative evidence on the evolution of sonnets in Spanish, and our findings regarding metrics and enjambment. The corpus contains 4,085 sonnets by 1,204 Spanish and Latin American authors (15th to 19th centuries), encoded in TEI, with RDFa attributes. The corpus aims at breadth, including many peripheral authors besides some major ones. Author metadata were encoded (dates, origin, gender). Scansion and enjambment were annotated automatically, with the ADSO and ANJA tools. The range of authors and periods, the use of TEI and RDFa for interoperability, and the combination of metrical and enjambment annotations goes beyond previously available digital resources. The corpus allowed us to examine the evolution of metrical patterns and their combinations after the Golden Age, complementing earlier studies. We also observed an increase in enjambment across the tercets in the 19th century, which may indicate increased variety in the discourse organization of sonnets in the period.
Supernova host galaxies in the dark energy survey: I. Deep coadds, photometry, and stellar masses
Authors: Wiseman P , Smith M , Childress M , Kelsey L , Möller A , Gupta R R , Swann E , Angus C R , Brout D , Davis T M , Foley R J , Frohmaier C , Galbany L , Gutiérrez C P , Inserra C , Kessler R , Lewis G F , Lidman C , Macaulay E , Nichol R C , Pursiainen M , Sako M , Scolnic D , Sommer N E , Sullivan M , Tucker B E , Abbott T M C , Aguena M , Allam S , Avila S , Bertin E , Brooks D , Buckley-Geer E , Burke D L , Carnero Rosell A , Carollo D , Carrasco Kind M , da Costa L N , De Vicente J , Desai S , Diehl H T , Doel P , Eifler T F , Everett S , Fosalba P , Frieman J , García-Bellido J , Gaztanaga E , Gerdes D W , Gill M S S , Glazebrook K , Gruendl R A , Gschwend J , Hartley W G , Hinton S R , Hollowood D L , Honscheid K , James D J , Kuehn K , Kuropatkin N , Lima M , Maia M A G , March M , Martini P , Melchior P , Menanteau F , Miquel R , Ogando R L C , Paz-Chinchón F , Plazas A A , Romer A K , Roodman A , Sanchez E , Scarpine V , Serrano S , Suchyta E , Swanson M E C , Tarle G , Thomas D , Tucker D L , Varga T N , Walker A R , Wilkinson R D ,   (DES Collaboration)
Published: May 2020

The 5-yr Dark Energy Survey Supernova Programme (DES-SN) is one of the largest and deepest transient surveys to date in terms of volume and number of supernovae. Identifying and characterizing the host galaxies of transients plays a key role in their classification, the study of their formation mechanisms, and the cosmological analyses. To derive accurate host galaxy properties, we create depth-optimized coadds using single-epoch DES-SN images that are selected based on sky and atmospheric conditions. For each of the five DES-SN seasons, a separate coadd is made from the other four seasons such that each SN has a corresponding deep coadd with no contaminating SN emission. The coadds reach limiting magnitudes of order ∼27 in g band, and have a much smaller magnitude uncertainty than the previous DES-SN host templates, particularly for faint objects. We present the resulting multiband photometry of host galaxies for samples of spectroscopically confirmed type Ia (SNe Ia), core-collapse (CCSNe), and superluminous (SLSNe) as well as rapidly evolving transients (RETs) discovered by DES-SN. We derive host galaxy stellar masses and probabilistically compare stellar-mass distributions to samples from other surveys. We find that the DES spectroscopically confirmed sample of SNe Ia selects preferentially fewer high-mass hosts at high-redshift compared to other surveys, while at low redshift the distributions are consistent. DES CCSNe and SLSNe hosts are similar to other samples, while RET hosts are unlike the hosts of any other transients, although these differences have not been disentangled from selection effects.
Duality rules for more mixed-symmetry potentials
Authors: Sakatani Yuho
Published: May 2020

$T$ - and $S$-duality rules among the gauge potentials in type II supergravities are studied. In particular, by following the approach of [J. J. Fernández-Melgarejo et al., arXiv:1909.01335], we determine the $T$- and $S$-duality rules for certain mixed-symmetry potentials, which couple to supersymmetric branes with tension $T\propto g_s^{-n}$ ($n\leq 4$). Although the $T$-duality rules are rather intricate, we find a certain redefinition of potentials which considerably simplifies the duality rules. After the redefinition, potentials are identified with components of the $T$-duality-covariant potentials, which have been predicted by the $E_{11}$ conjecture. Since our approach is based on $U$-duality, we can also determine the 11D uplifts of the mixed-symmetry potential, unlike the $T$-duality-covariant approach known in the literature. We also study the field strengths of the mixed-symmetry potentials.
Sixty-One Years Following Registration, Phorate Applied In-Furrow at Planting Suppresses Development of Late Leaf Spot on Peanut
Authors: Anco Daniel J. , Thomas James S. , Wright David L. , Dufault Nicholas S. , Small Ian M.
Published: May 2020

Late and early leaf spot are caused by Nothopassalora personata and Passalora arachidicola, respectively, and are damaging diseases of peanut (Arachis hypogaea L.) capable of defoliation and yield loss. Management of these diseases is most effective through the integration of tactics that reduce starting inoculum and prevent infection. The insecticide phorate was first registered in 1959 and has been used in peanut production for decades in-furrow at planting to suppress thrips. Phorate further provides significant suppression of Tomato spotted wilt virus infection beyond suppression of its thrips vector alone by activating defense-related responses in the peanut plant. From six experiments conducted from 2017 to 2019 in Blackville, SC, Reddick, FL, and Quincy, FL, significantly less leaf spot defoliation was exhibited on peanuts treated with phorate in-furrow at planting (26%) compared with nontreated checks (48%). In-season fungicides were excluded from five of the experiments, whereas the 2018 Quincy, FL, experiment included eight applications on a 15-day interval. Across individual experiments, significant suppression of defoliation caused by late leaf spot was observed from 64 to 147 days after planting. Although more variable within location-years, pod yield following phorate treatment was overall significantly greater than for nontreated peanut (2,330 compared with 2,030 kg/ha; P = 0.0794). The consistent defoliation suppression potential was estimated to confer an average potential net economic yield savings of $90 to $120 per hectare under analogous leaf spot defoliation. To our knowledge, these are the first data in the 61 years since its registration demonstrating significant suppression of leaf spot on peanut following application of phorate in-furrow at planting. Results support phorate use in peanut as an effective and economical tactic to incorporate to manage late and early leaf spot infections and development of fungicide resistance.
Recent clinical trials in valvular heart diseases
Authors: Goel Sunny , Ro Richard , Lerakis Stamatios , Khera Sahil
Published: May 2020

Purpose of review

In recent years, no other field of cardiology has experienced a greater influx of transformational therapeutic options as valvular heart disease. The present review discusses the landmark trials published in the last 18 months that have shaped the modern day management of valvular heart diseases.

Recent findings

There have been several landmark trials in recent years, which have expanded the indications for transcatheter aortic valve replacement to low-risk surgical patients and the use of MitraClip for patients with functional mitral regurgitation. Options for transcatheter management of right-sided valvular disease also continue to evolve, including promising results from early feasibility studies.

The development of novel transcatheter therapies for valvular heart disease has expanded the armamentarium of physicians treating patients with valvular heart disease. The present review will focus on the recent (within 2 years) trials in this field of interest.
Redefining vision assessment
Authors: Brown Colin E. , Waring George O. , Rocha Karolinne M.
Published: May 2020

Purpose of review

This review outlines ophthalmic diagnostic systems, which objectively evaluates the human visual system and its potential beyond that of Snellen acuity.

Recent findings

Advances in ophthalmic diagnostic systems have allowed for a deeper understanding of the optical principles of the human eye and have created the opportunity to evolve our current standards of vision assessment beyond Snellen acuity charts. Definitive comparative and validation trials will continue to be necessary in order for these advanced diagnostics to gain more widespread acceptance in the specialty, in addition to providing the guidance on the specific indications and utilities.

Advancements in wavefront analysis, light scatter measurements, and adaptive optics technologies can provide greater insight into an individual optical system's potential and irregularities. Modalities that test for anterior corneal surface and whole eye aberrations, light scatter and contrast sensitivity can be an excellent educational tool for our patients to help them better understand their visual dysfunction and can prove useful for medical or surgical decision-making.
Rapamycin induces megakaryocytic differentiation through increasing autophagy in Dami cells
Authors: Sun Rui-Jie , Yuan Dai , Liu Shu-yan , Zhu Jing-jing , Shan Ning-ning
Published: May 2020

Autophagy is a conserved cellular process that involves the degradation of cytoplasmic components in eukaryotic cells. However, the correlation between autophagy and megakaryocyte development is unclear. This study aims to explore the role of autophagy in megakaryocyte differentiation. To test our hypothesis, we used the Dami cell line in-vitro experiments. Rapamycin and Bafilomycin A1 were used to stimulate Dami cells. CD41 expression and apoptosis were analysed by flow cytometry. Autophagy-related proteins were detected by Western blotting. 12-O-Tetradecanoylphorbol 13-acetate-treated Dami cells can simulate endomitosis of megakaryocytes in vitro. Rapamycin-induced autophagic cell death was verified by LC3-II conversion upregulation. Meanwhile, Bafilomycin A1 blocked endomitosis and autophagy of Dami cells. Our results provide evidence that autophagy is involved in megakaryocyte endomitosis and platelet development. Rapamycin inhibited cell viability and induced multiple cellular events, including apoptosis, autophagic cell death, and megakaryocytic differentiation, in human Dami cells. Upregulated autophagy triggered by rapamycin can promote the differentiation of Dami cells, while endomitosis is accompanied by enhanced autophagy.
Cervical Necrotizing Fasciitis After Surgery of a Mandibular Fracture
Authors: Badri Amir Ali , Hasheminasab Mahboube Sadat , Bolandparva Farzaneh
Published: May 2020

Introduction:

Cervical necrotizing fasciitis (CNF) is a rapid progressing and potentially fatal infection of connective tissues that spreads along the fascial planes. It commonly develops from odontogenic sources. In this article, the authors present a case of CNF which was developed after open reduction and internal fixation (ORIF) of a mandibular fracture.

Clinical case:

A 19-year-old male patient with no past medical history was admitted due to a mandibular fracture. Following ORIF surgery, on third post-operative day, Physical examination revealed extensive cervical swelling extending from submandibular to suprasternal area, with tender and erythematous skin. Soon after confirmation of CNF diagnosis, surgical debridement and wide spectrum antibiotic therapy was performed. The residual soft tissue defect was reconstructed following infection subsidence.

Conclusion:

Our study aims to highlight the risk of CNF development during postoperative period of a simple mandibular fracture ORIF surgery which is considered a routine maxillofacial procedure. Early detection and adequate emergency treatment including immediate surgical intervention are critical in the management of these patients.
What Should I Do?
Authors: Hanto Douglas W.
Published: May 2020

The aim of the study was to examine the conflicting duties of a practicing surgeon who is at high risk for morbidity and mortality from Covid-19 infection. Should he opt out of the care of these patients or does his duty to care override other considerations? Older adults and those with serious medical conditions are at much greater risk for severe disease and death from Covid-19 infection. As a practicing frontline surgeon in a high risk group, the hospital offered the author, and other health care providers at high risk, the option to opt out of the care Covid-19 suspected or infected patients before an anticipated surge. What should the surgeon and other health care providers do? This is a question many are asking and having to answer. In this article, the author describes how difficult the situation of having any choice at all was and then how difficult it was to arrive at a decision. The duty to care and its limits, as well as obligations to society, family, co-workers, and to self, are examined. The author considers how he and others can contribute in other ways to patients and providers. The author arrives at a morally permissible and a rational decision to opt out. Health care workers at high risk can contribute in other ways to patients and providers. It still may not feel right.
Mini-invasive Surgery and Parastomal Hernia: Higher Frequency and No Prophylactic Mesh Effect
Authors: Lambrecht Jan R.
Published: May 2020

Aim:

Parastomal hernia (PSH) is very common. Recent reports suggest increased frequency after laparoscopic stoma formation compared with open surgery. A retrospective chart review was designed to appraise the outcomes regarding PSH in open and in laparoscopic procedures.

Materials and Methods:

All patients operated by rectal resection and planned end-colostomy in the period from 2004 to 2018 were reviewed. A total of 70 open and 101 laparoscopic operations were identified. A modified retromuscular mesh application through the trephine was used for the prevention of PSH in 42% of patients in the laparoscopic group.

Results:

The median follow-up was 58 (1 to 167) months in the open group and 43 (0 to 153) months in the laparoscopic group. Patient characteristics were evenly distributed between the groups, except for more male patients and higher American Society of Anesthesiologists Score as well as higher rates of patients with neoadjuvant treatment and mesh prophylaxis, in the laparoscopic group. Clinical PSH occurrences were 2 (3%) in the open group and 18 (18%) in the laparoscopic group (P=0.00). Propensity-weighted analysis estimates increased odds ratio (OR) for PSH in the laparoscopic group [OR=11.8; 95% confidence interval (CI): 1.4-96.6]. PSH repair rates were 0 in the open group and 6/18 (33%) in the laparoscopic group. Mesh prophylaxis in the laparoscopic group did not influence PSH outcome (OR=1.4; 95% CI: 0.5-4.0). Computed tomography scans were assessable in 48 and 66 patients, with median follow-up timepoints of 42 and 30 months in the open and laparoscopic groups, respectively, and 8 (18%) and 21 patients (32%) were diagnosed with PSH. Computed tomography assessment implied an increased risk for PSH in laparoscopy (OR=3.5; 95% CI: 1.1-11.9). Aggregate of chart and computed tomography occurrence of PSH showed an equivalent hazard (OR=3.2; 95% CI: 1.1-9.5).

Interpretations:

Laparoscopic operations with stoma formation seem to have an increased rate of PSH in comparison with open operations and the results support previous claims. Retromuscular keyhole mesh placement may not be the ideal method of PSH prevention in laparoscopic stoma formation.
Laparoscopic Splenic Vessels and Spleen Preservation Distal Pancreatectomy Via Inferior-Posterior Splenic Vein Approach
Authors: Liao Ting Kai , Wang Chih-Jung , Su Ping-Jui , Lui Wei-Hsun , Chao Ying Jui , Sy Edgar D. , Shan Yan-Shen
Published: May 2020

Background:

Preservation of splenic vessels can minimize the risks of splenic infarction and gastric varices in laparoscopic spleen preserving distal pancreatectomy. A well-established procedure would provide high splenic vessels and spleen preservation rate. This study evaluated the outcomes and depending factors of laparoscopic splenic vessels and spleen preservation distal pancreatectomy (LsvspDP) via inferior-posterior splenic vein approach.

Materials and Methods:

This retrospective study enrolled patients who underwent LsvspDP via inferior-posterior splenic vein approach in National Cheng-Kung University Hospital from February 2009 to June 2019. The clinic-pathologic data were collected and analyzed. The primary outcome of this study was the learning curve based on the cumulative sum analysis. The secondary outcomes were to evaluate the critical factors for the failure of splenic vessels and spleen preservation.

Results:

During the study period, a total of 64 patients received LsvspDP attempt. Splenic vessels were successfully preserved in 49 patients and the overall spleen preservation rate was 76.6%. According to cumulative sum analysis, the learning curve of LsvspDP was the 33rd case and several plateaus were observed during the learning curve phase. Old age (P=0.001), tail location (P=0.038), and large tumor (P=0.01) were independent risk factors of failed splenic vessels preservation, whereas the cut-off point of tumor size for prediction of spleen preservation was 5.4 cm. The complication rates were 7.8%, 7.8%, and 12.5% for Clavien grade I, II, and III, respectively, and 0% for Clavien grade IV or V. The rate of postoperative pancreatic fistula-grade B was 14.8%, among which the tail location was lower than the nontail location (0% vs. 24.3%; P=0.008). The mean value of operative time, blood loss, and hospital stay were 198±67 minutes, 139±242 mL, and 8.5±5.6 days, respectively.

Conclusions:

In LsvspDP, the inferior-posterior splenic vein approach resulted in high splenic vessels and spleen preservation rate. Thirty-three patients were required to overcome the learning curve. Old age, tail location, and large tumor size were independent factors for the failure of splenic vessels preservation, whereas the cut-off value for tumor size was 5.4 cm to predict splenic vessels preservation.
Safety and Efficacy of Through-the-Scope Placement of Colonic Self-expandable Metal Stents Without Fluoroscopic Guidance: A Retrospective Cohort Study
Authors: Zhou Ying , Zhang Xie , Kang Jinyu , Zhang Xuesong , Song Yufei
Published: May 2020

Background:

Colonic self-expandable metal stents (SEMSs) are usually placed through an endoscope under fluoroscopic guidance. In this retrospective study, we measured the safety and efficacy of through-the-scope colonic stent placement without fluoroscopic guidance.

Materials and Methods:

We included consecutive patients with malignant colonic obstruction who underwent SEMS placement through the endoscope without fluoroscopic guidance (NF group) from 2016 to June 2019 in a single tertiary medical center. Technical and clinical success rates and complication rates were compared with those of a historical control group consisting of consecutive patients who underwent stent placement through the endoscope under fluoroscopic guidance (F group) from 2012 to 2015.

Results:

Of 136 patients analyzed, 67 were in the NF group and 69 were in the F group. For the NF and F groups, technical success rates were 97.0% and 95.7%, respectively (P=0.763); clinical success rates were 92.5% and 89.9%, respectively (P=0.581). Major complications included perforation (NF group, 1.5%; F group, 1.4%), stent migration (NF group, 0; F group, 1.4%), and stent occlusion (NF group, 1.5%; F group, 2.9%) (P=0.425). The median procedure time was significantly lower in the NF group (25.90±18.68 min) than in the F group (44.23±20.40 min) (P<0.001).

Conclusions:

Colonic SEMS placement without fluoroscopy is as safe and effective as the conventional fluoroscopically guided approach. This new method significantly reduced the procedure time.
Exploration of the virome of the European brown shrimp (Crangon crangon)
Authors: Van Eynde Benigna , Christiaens Olivier , Delbare Daan , Shi Chenyan , Vanhulle Emiel , Yinda Claude Kwe , Matthijnssens Jelle , Smagghe Guy
Published: May 2020

Crangon crangon is economically a very important species. Recently, promising culture attempts have been made, but a major problem is the uncontrollable mortality during the grow-out phase. As of yet, the life cycle of C. crangon is not closed in captivity so wild-caught individuals are used for further rearing. Therefore, it is important to investigate the virome of C. crangon both in wild-caught animals as in cultured animals. In recent years, next-generation-sequencing (NGS) technologies have been very important in the unravelling of the virome of a wide range of environments and matrices, such as soil, sea, potable water, but also of a wide range of animal species. This will be the first report of a virome study in C. crangon using NGS in combination with the NetoVIR protocol. The near complete genomes of 16 novel viruses were described, most of which were rather distantly related to unclassified viruses or viruses belonging to the Picornavirales, Bunyavirales Nudiviridae, Parvoviridae, Flaviviridae, Hepeviridae, Tombusviridae, Narnaviridae, Nodaviridae, Sobemovirus. A difference in virome composition was observed between muscle and hepatopancreatic tissue, suggesting a distinct tissue tropism of several of these viruses. Some differences in the viral composition were noted between the cultured and wild shrimp, which could indicate that in sub-optimal aquaculture conditions some viruses become more abundant. This research showed that a plethora of unknown viruses is present in C. crangon and that more research is needed to determine which virus is potentially dangerous for the culture of C. crangon.
St George’s COVID shield for use by ENT surgeons performing tracheostomies
Authors: Brar Sabrina , Daya Jahan , Schuster-Bruce James , Krishna Sanjeev , Daya Hamid
Published: May 2020

Healthcare workers are at increased risk of exposure to COVID-19. The majority of cases are acquired through inhalation of infected respiratory particles, contamination with infected surfaces or whilst performing aerosol-generating procedures. Basic infection prevention measures are essential to protect healthcare workers from contracting the disease when managing patients; consequently global demand for personal protective equipment (PPE) has exceeded supply in many regions. We present a novel, innovative polycarbonate shield designed for ENT clinicians performing tracheostomies. Clinical investigations using the shield demonstrated a sixteen-fold decrease in the number of particles detected at the position of the operating surgeon when the shield was used (particle size 0.3μm; with shield 27,000 versus 439,000 without shield). The shield, used with appropriate PPE, could therefore help to minimise exposure to aerosol generated particles such as during tracheostomies on patients with COVID-19.
The ongoing COVID-19 epidemic in Minas Gerais, Brazil: insights from epidemiological data and SARS-CoV-2 whole genome sequencing
Authors: Xavier Joilson , Giovanetti Marta , Adelino Talita , Fonseca Vagner , da Costa Alana Vitor Barbosa , Ribeiro Adriana Aparecida , Felicio Katlin Nascimento , Duarte Clara Guerra , Silva Marcos Vinicius Ferreira , Salgado Álvaro , Lima Mauricio Teixeira , Jesus Ronaldo de , Fabri Allison , Zoboli Cristiane Franco Soares , Santos Thales Gutemberg Souza , Iani Felipe , de Filippis Ana Maria Bispo , de Siqueira Marilda Agudo Mendonça Teixeira , de Abreu André Luiz , de Azevedo Vasco , Ramalho Dario Brock , de Albuquerque Carlos F. Campelo , de Oliveira Tulio , Holmes Edward C. , Lourenço José , Alcantara Luiz Carlos Junior , Oliveira Marluce Aparecida Assunção
Published: May 2020

The recent emergence of a previously unknown coronavirus (SARS-CoV-2), first confirmed in the city of Wuhan in China in December 2019, has caused serious public health and economic issues due to its rapid dissemination worldwide. Although 61,888 confirmed cases had been reported in Brazil by 28 April 2020, little was known about the SARS-CoV-2 epidemic in the country. To better understand the recent epidemic in the second most populous state in southeast Brazil (Minas Gerais, MG), we looked at existing epidemiological data from 3 states and sequenced 40 complete genomes from MG cases using Nanopore. We found evidence of multiple independent introductions from outside MG, both from genome analyses and the overly dispersed distribution of reported cases and deaths. Epidemiological estimates of the reproductive number using different data sources and theoretical assumptions all suggest a reduction in transmission potential since the first reported case, but potential for sustained transmission in the near future. The estimated date of introduction in Brazil was consistent with epidemiological data from the first case of a returning-traveler from Lombardy, Italy. These findings highlight the unique reality of MG’s epidemic and reinforce the need for real-time and continued genomic surveillance strategies as a way of understanding and therefore preparing against the epidemic spread of emerging viral pathogens.