bluuebunny/crossref_metadata_2025 huggingface dataset:
Systematic analysis of control techniques for the dual active bridge converter in photovoltaic applications
Authors: Herrera‐Jaramillo Diego Alejandro , González Montoya Daniel , Henao‐Bravo Elkin Edilberto , Ramos‐Paja Carlos Andrés , Saavedra‐Montes Andrés Julián
Published: April 2021

The dual active bridge (DAB) converter has high efficiency and versatility; hence, such a converter has been used to design photovoltaic (PV) applications with both step‐up and step‐down voltage capabilities. However, PV systems require maximum power point tracking (MPPT) controllers to track the optimal operation conditions; moreover, PV voltage controllers are required to reject load perturbations that reduce the MPPT performance. This paper describes the operation of a DAB converter in PV systems and compares the performance of the DAB converter with a classical boost solution. In addition, this paper also presents a systematic analysis of the control techniques for DAB converters in PV applications, which provides useful information for selecting the most suitable approach for a particular application.
Quaternary corals (Scleractinia: Merulinidae) from the Egyptian and Saudi Arabian Red Sea Coast
Authors: Khalil Hamza M. , Fathy Mohamed S. , Al Sawy Samar M.
Published: April 2021

This work provides a comprehensive description of the Scleractinian family Merulinidae (Verrill, 1865) of the Red Sea at species level based on skeletal structure for helping in evaluating and estimation of actual species diversity, as well as predicting their response to environmental changes. The present study is a first attempt to describe and illustrate the coral species of the family Merulinidae in the Farasan Islands (Saudi Arabian Coast). Moreover, coral reef terraces are investigated around El Quseir‐Marsa Alam area on the Egyptian Red Sea Coast. Overall, 42 scleractinian coral species from the family Merulinidae (Verrill, 1865) have been identified. They belong to 14 genera: Dipsastraea, Favites, Echinopora, Goniastrea, Coelastrea, Paragoniastrea, Paramontastraea, Astrea, Cyphastrea, Erythrastrea, Merulina, Platygyra, Leptoria, and Hydnophora. About 37 species are recorded for the first time from the Farasan Islands and 26 species from El Quseir‐Marsa Alam area, among them three species are recognized as new records. Two species are added to coral communities of the Red Sea (Goniastrea favulus and Paragoniastrea deformis), and six species were added to the fossil record of the Red Sea. The terminology, systematic classification, and the criteria of identification for all studied coral taxa are generally updated according to recent results. The known age and all recorded stratigraphic range of these species are illustrated and discussed. From the results, most of the corals are still living in the present Red Sea except for three species: Favites micropentagonus, Goniastrea favulus, and Paragoniastrea deformis. All species are extended down to the Pleistocene and a few to the Pliocene and Miocene.
Grid mapping revealed hidden geochemical lens and its chemostratigraphic bias in the middle‐upper Permian marine carbonate sequence in Laibin, South China
Authors: MA Qing , YE Facheng , Wang Wei , Sheng Yidi , Shu Ling , Chen Xiaozheng
Published: April 2021

Deep‐time chemostratigraphy provides important data for stratigraphy and palaeoenvironmental reconstruction. Geochemical analysis for the same proxy from the same outcrop section, however, often results in different data among various researchers. The dispute was ascribed to inappropriate screening of samples weathering, pre‐treatment, and analytical methods. An outstanding example is that a great variation of 1–3‰ in δ13CVPDBvalues from the same horizons at Auxiliary Global Stratotype of Section and Point for the Guadalupian–Lopingian (G‐L) boundary in Tieqiao, Laibin, South China was obtained by various research groups. The Walther's Law of Facies suggests that such differences in analytical results may be due to the diachronism of samples measured in high‐resolution stratigraphy. Although lithology and broad sedimentary facies are the same in a lithostratigraphic unit, heterogeneous distribution of bioclastics, δ13Corg, provenances, trace elements, and age‐controlling geochemical signals might have printed on sediments within the same bed. Here, we verified the variations by grid mapping and sampling, a new method for high‐resolution chemostratigraphy, and this practice is applied to the auxiliary GSSP at the Tieqiao section. A total of nine parallel columnar sections from the upper Guadalupian to lowest Lopingian were measured and sampled. In addition, four lateral profiles along four beds were also sampled, and two of them are close to the lower part of the section (upper Guadalupian) and near the G‐L boundary, respectively. These analytical results are plotted along the coordinate ofX–Yaxis and form the grid mapping on the outcrop. Contour maps of various proxies (i.e., CaO%, total Fe%, and δ13Ccarb) based on the grid mapping were constructed on the outcrop, instead of single excursions of various geochemical proxies throughout the upper Guadalupian to lowest Lopingian. The results show different negative excursions of δ13Ccarbcoinciding with biotic extinction near the G‐L boundary and answered the differences of proxy reported in previous studies. Grid mapping of various proxies shows general trends of the proxies on the outcrop; however, there are invisible beddings across lenses in dozens meters size of geochemical abnormal. Analytical data of the same proxy from the same horizons at different columnar sections may present different excursions if sampling on the abnormal lenses or not. This is why the data are different among various studies when different columnar sections were sampled. Various lenses of geochemical abnormal which may be linked tectonic controlled diagenesis, and microhabitat et al., and resulted in the bias from different columnar sections were sampled.
Prevalence of depression, anxiety, and apathy symptoms across dementia stages: A systematic review and meta‐analysis
Authors: Leung Dara K.Y. , Chan Wai Chi , Spector Aimee , Wong Gloria H.Y.
Published: April 2021

Objective

The present study aimed to resolve inconsistency in reported prevalence of affective symptoms by dementia stage.

Methods/Design

We conducted a meta‐analysis of studies with data on dementia stage and prevalence of depression, anxiety, or apathy assessed using validated tools. We performed random‐effects meta‐analysis and subgroup analysis on symptom prevalence by dementia stage, according to CDR.

Results

The meta‐analysis included 5897 people with dementia from 20 studies. Prevalence rates of depression in mild, moderate, and severe dementia were 38% (95% CI 32%–45%), 41% (95% CI 33%–49%), and 37% (95% CI 17%–56%) respectively. The corresponding prevalence for anxiety was 38% (95% CI 31%–45%), 41% (95% CI 31%–52%), and 37% (95% CI −8%–82%); and 54% (95% CI 45%–62%), 59% (95% CI 44%–73%), and 43% (95% CI 10%–75%) for apathy. The prevalence of depression, anxiety, and apathy did not differ with regard to dementia stage and type. The prevalence of depression in Alzheimer's disease (AD) was significantly lower when it was assessed using diagnostic criteria compared to screening tools. The prevalence of depression in AD was lowest in America, while anxiety in vascular dementia was higher in Europe than Asia.

Conclusions

Depression, anxiety, and apathy symptoms are highly prevalent across dementia stages. There is no evidence of any changes in prevalence of affective symptom as the illness progresses. Evaluation methods and cultural difference may explain some of the variance, suggesting further investigation of factors that may influence the report of symptoms, such as carer psychosocial characteristics, and more cross‐cultural studies are needed.
Pediatric and adolescent gynecology through a global lens
Authors: Roos Eveline J. , Simms‐Cendan Judy , Cheung Charleen , Laufer Deborah , Grover Sonia R. ,   FIGIJ board in collaboration with FIGO
Published: April 2021

Girls and adolescents, aged 0–19 years make up almost 30% of the world’s female population yet their specific healthcare needs often slip between the gaps of pediatrics and adult women’s health. Pediatric and adolescent gynecology is the clinical field that endeavors to address the reproductive health needs of this age group. The environment and psychosocial well‐being, social determinants of health, have direct bearing on reproductive health, affecting menstrual cycles, menstrual hygiene, and risks for unintended pregnancy and sexually transmitted infections. This narrative review will highlight common gynecologic conditions of adolescents, especially where diagnosis and management are distinct from adult women. It will also present preventive health strategies to improve reproductive health through vaccination, improved access to hygiene supplies and contraception.
Impact of boric acid and saline water irrigation on germination and seedling establishment of wheat*
Authors: Al‐Tabbal Jalal , Al‐Zboon Kamel K.
Published: April 2021

The main purpose of this experiment was to investigate the effects of salinized water with boric acid and sodium chloride (NaCl) on seed germination and seedling establishment of wheat. The following treatments were applied: Boric acid solution (0, 40, 240, and 480 μM) and NaCl solution (0, 50, 250, and 1,000 μM) were combined to produce 16 different solutions. The highest germination percentages were found in distilled water. Shoot length and root length of wheat were reduced by increments of all boric acid treatments in both saline solution and distilled water, but the decrease in shoot length due to boron toxicity was significant more pronounced in saline conditions. The greatest shoot and root lengths were observed in the control treatment (distilled water), and the smallest lengths were observed in the highest boric acid treatment (480 μM). Shoot and root dry weight also decreased with increasing boric acid. The averages of variables were also significantly affected by salinity solutions, but to a greater extent than under the influence of boric acid. It is concluded that wheat plants cannot tolerate salinized water with boric acid and NaCl during the germination stage.
New nanocomposite made of cashew apple bagasse lignin and Fe3O4 for immobilizing of lipase B from Candida antarctica aiming at esterification
Authors: Serpa Juliana de França , Matias Gabriel AB , Fechine Pierre BA , da Costa Victor M , Freire Rafael M , Denardin Juliano C , Gonçalves Luciana RB , de Macedo André C , Rocha Maria VP
Published: April 2021

BACKGROUND

Novel magnetite‐lignin hybrid materials were synthesized using lignin from cashew apple bagasse (CAB) and iron oxide nanoparticles (magnetite, Fe3O4). The new material, termed MNs/Lig (magnetite conjugated with lignin), was used as a support for the immobilization of lipase B from Candida antarctica (CAL─B), aiming to obtain an active and stable biocatalyst that is easily recoverable from the reactional medium.

RESULTS

The magnetite/lignin composite showed a higher thermal stability than pure lignin, and it presented good magnetic properties, both before and after the immobilization procedure. The immobilization yield was higher using the unaltered MN/Lig as a support than when using the glutaraldehyde‐activated MNs/Lig (MNs/Lig_GA), with yields of 66.6% and 40.0%, respectively. The presence of Triton X‐100 did not influence the immobilization yield or the thermal stability of the biocatalyst when employing the unaltered MNs/Lig. However, it influenced the thermal stability of the lipase immobilized on MNs/Lig_GA, lowering the biocatalyst stability, which showed a half‐life 11‐fold lower than that of MNs/Lig_GA_CALB. The biocatalysts were tested with regards to the synthesis of ethyl oleate using oleic acid and ethanol as substrates, and 2‐ethylhexyl oleate (a biolubricant) using oleic acid and 2‐ethyl‐hexanol as substrate. The conversions obtained by MNs/Lig_Tri_CALB were 88.2% and 76.7% for ethyl oleate and 2‐ethylhexyl oleate, respectively.

CONCLUSION

The novel strategy presented in this work for obtaining a biocatalyst using synthesized hybrids (MNs/Lig) may be a promising route for lipase immobilization because it can be considered environmentally benign and it shows a strong potential use in several reactions of industrial interest. © 2021 Society of Chemical Industry (SCI).
Resolution of peri‐implantitis by means of implantoplasty as adjunct to surgical therapy: A retrospective study
Authors: Monje Alberto , Pons Ramón , Amerio Ettore , Wang Hom‐Lay , Nart José
Published: April 2021

Background

There is a paucity of data on the effectiveness of implantoplasty as adjunct to the surgical management of peri‐implantitis. The purpose of this study was to evaluate the resolution of peri‐implantitis by means of implantoplasty as adjunct to surgical resective (RES) and reconstructive (REC) therapies and supportive maintenance.

Methods

Patients that underwent surgical therapy to manage peri‐implantitis with a follow‐up of ≥12 months and enrolled in a regular peri‐implant supportive care were recruited. RES group consisted of two interventions that included osseous recontouring and apically position flap (APF) and soft tissue conditioning (STC). REC was performed in the infra‐osseous compartment of combined defects. Implant survival rate was recorded. Clinical and radiographic parameters were evaluated to define a “dogmatic” (case definition #1) and a “flexible” (case definition #2) therapeutic success. Univariate and multivariate multilevel backward logistic regression were applied for statistical analysis.

Results

Overall, 43 patients (nimplants = 135) were retrospectively assessed. Mean observational period was ∼24 months. Implant survival rate was 97.8%, being significantly higher for APF, STC, and APF + STC (RES) when compared with REC (P = 0.01) therapy, in particular for advanced lesions (>50% of bone loss). The overall therapeutic success rate at implant‐level was 66% and 79.5% for case definition #1 and #2, respectively. APF group displayed more efficient disease resolution when considered success definition #1 (72%). Contrarily, when the data were adhered to success definition #2, STC group showed a slightly higher disease resolution rate (87%). For RES group, location, favoring anterior (P = 0.04) and defect type, favoring class II (P = 0.02) displayed statistical significance for therapeutic success. For REC group, implants exhibiting a wider band of keratinized mucosa (KM) demonstrated higher therapeutic success (P = 0.008).

Conclusion

Implantoplasty as an adjunct to surgical therapy proved effective in terms of disease resolution and implant survival rate. Implant location, defect morphology as well as the buccal width of KM are indicators of therapeutic success.
Mixed‐mode open tubular column for peptide separations by capillary electrochromatography
Authors: Ali Faiz , AlOthman Zeid A. , Al‐Shaalan Nora Hamad
Published: April 2021

Mixed‐mode chromatography open tubular column has been developed for peptide separation in electrochromatography. A column with 92 cm effective length and 50 μm internal diameter is fabricated internally with a copolymer sheet of restricted thickness. Catalyst facilitated binding of the coupling agent 3,5‐bis (trifluoromethyl) phenyl isocyanate has been carried out at the interior surface of the column. The initiator sodium diethyldithiocarbamate was bound to the coupling agent. A small amount ofN‐[2‐(acryloylamino) phenyl] acrylamide was used along with methacrylic acid and styrene in the monomer mixture to induce a little polar character in the stationary phase fabricated inside the column. Twenty‐three peptides have been separated from a chemically digested protein mixture present in cytochrome C in capillary electrochromatography, in addition to the separation of six commercial peptides. We achieved an average plate count of over 1.5 million/m with the column of current study both for the digested protein components and commercial peptides using 70/30% v/v (acetonitrile/20 mM ammonium formate) at pH 6.5. In addition, the column resulted in baseline separation of all the peptides with very good resolution, enhanced peak capacity, and better retention time span.
Opening the Palatovaginal Canal to Maximize Anterior Sphenoidotomy in Endoscopic Endonasal Surgery
Authors: Ogawa Daisuke , Akutsu Hiroyoshi , Tanaka Shuho , Hara Takuma , Kino Hiroyoshi , Miyamoto Hidetaka , Ii Rieko , Miyake Keisuke , Tamiya Takashi , Ishikawa Eiichi
Published: April 2021

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Automated delineation of orbital abscess depicted on CT scan using deep learning
Authors: Fu Roxana , Leader Joseph K. , Pradeep Tejus , Shi Junli , Meng Xin , Zhang Yanchun , Pu Jiantao
Published: April 2021

Objectives

To develop and validate a deep learning algorithm to automatically detect and segment an orbital abscess depicted on computed tomography (CT).

Methods

We retrospectively collected orbital CT scans acquired on 67 pediatric subjects with a confirmed orbital abscess in the setting of infectious orbital cellulitis. A context‐aware convolutional neural network (CA‐CNN) was developed and trained to automatically segment orbital abscess. To reduce the requirement for a large dataset, transfer learning was used by leveraging a pre‐trained model for CT‐based lung segmentation. An ophthalmologist manually delineated orbital abscesses depicted on the CT images. The classical U‐Net and the CA‐CNN models with and without transfer learning were trained and tested on the collected dataset using the 10‐fold cross‐validation method. Dice coefficient, Jaccard index, and Hausdorff distance were used as performance metrics to assess the agreement between the computerized and manual segmentations.

Results

The context‐aware U‐Net with transfer learning achieved an average Dice coefficient and Jaccard index of 0.78 ± 0.12 and 0.65 ± 0.13, which were consistently higher than the classical U‐Net or the context‐aware U‐Net without transfer learning (P < 0.01). The average differences of the abscess between the computerized results and the experts in terms of volume and Hausdorff distance were 0.10 ± 0.11 mL and 1.94 ± 1.21 mm, respectively. The context‐aware U‐Net detected all orbital abscess without false positives.

Conclusions

The deep learning solution demonstrated promising performance in detecting and segmenting orbital abscesses on CT images in strong agreement with a human observer.
Effects of Two Activated Milt Residence Times on Landlocked Fall Chinook Salmon Egg Survival to the Eyed Stage of Development
Authors: Stevens Jeff , Voorhees Jill M. , Huysman Nathan , Krebs Eric , Barnes Michael E.
Published: April 2021

During salmonid spawning, the amount of time required for activated milt to successfully fertilize eggs has not been well defined. This study examined the effects of two different activated milt residence times, 20 and 60 s, during production-scale artificial spawning of 20 landlocked fall Chinook Salmon Oncorhynchus tshawytscha. Mean (SE) survival to the eyed stage of egg development was 29.2% (5.5) in the eggs that were subjected to the 20-s milt residence time, which was not significantly different from the 32.3% (5.7) survival rate for eggs with the 60-s residence time. There was considerable variation in egg survival among the individual female spawns, ranging from near 0% to 76.7%. These production-scale results indicate that activated milt residence times as low as 20 s can be used during the landlocked fall Chinook Salmon spawning, with no significant effect on egg survival to the eyed stage of development.
E‐Replacement: Efficient scanner data collection method in P4‐based software‐defined networks
Authors: Cai Yun‐Zhan , Lin Ting‐Yu , Wang Yu‐Ting , Tuan Ya‐Pei , Tsai Meng‐Hsun
Published: April 2021

Internet of things (IoT) botnets such as Mirai are rampant in the past years. Port scanning is a well‐known behavior of botnets for searching targets in networks. To detect port scanning, a detector requires network statistics with high discriminatory power. In P4‐based software‐defined network (SDN), switches take charge of recording characteristics about scanning behaviors, and controllers pull the statistics from the switches periodically for anomaly detection. Given storage resources in switches are limited, we proposed a scanner data collection method, 0‐Replacement, in P4‐based SDN to efficiently collect scanner data and improve the detection rate. 0‐Replacement, however, does not consider performance degradation caused by the hash collision. In this paper, we combine the conception of Hashpipe with 0‐Replacement and propose a new scanner data collection method named E‐Replacement. By leveraging the conception of Hashpipe, E‐Replacement can mitigate the performance degradation caused by the hash collision. Through simulations, we show that E‐Replacement improves the detection rate by up to 6.73% and 210.82% compared to 0‐Replacement and the traditional sample and hold method, respectively. Besides, E‐Replacement improves the precision by around 528.2% compared to the count‐min sketch and k‐ary sketch methods. The memory usage in E‐Replacement is the same as 0‐Replacement. In simulations, E‐Replacement can detect around 93.4% of scanners in a class B network with only 4.02‐Mb SRAM. After implementing E‐Replacement on a software P4 switch, BMv2, we observe the extra forwarding latency for E‐Replacement is not greater than a millisecond.
Effect of Encapsulation of Boron Nanoparticles Using Reduced Graphene Oxide on their Oxidation Characteristics
Authors: Zhang Hongyi , Du Xinyi , Li Gang
Published: April 2021

Boron is a well‐known high‐energy solid. A thick oxide coating on the particle, however, inhibits its ignition and reduces its energy significantly. In this work, graphene nanosheets were used as a protective material for encapsulating boron nanoparticles (NPs) to prevent their oxidation from the air at room temperature. Boron‐reduced graphene oxide (RGO) composites were prepared under hydrothermal conditions using graphene oxide (GO) and commercial or washed boron NPs as precursors. Boron‐RGO composites were characterized using X‐ray diffraction (XRD), transmission electron microscopy (TEM), Raman spectroscopy, X‐ray photoelectron spectroscopy (XPS), thermogravimetry (TG), and differential scanning calorimetry (DSC). XPS data show that no boron oxide or boric acid was present on the surface of washed boron particles and boron‐RGO composites. It seems that the removal of boron oxide or boric acid layer on the commercial boron particle surface and the reduction of graphene oxide occurred simultaneously during hydrothermal treatment. XRD data show that boric acid re‐formed on washed boron NPs but not on the boron‐RGO composites after these two samples had been exposed to ambient temperature air for four months. This indicates that the anti‐oxidation stability of boron against air at room temperature was improved greatly after encapsulation of reduced graphene oxide. The heat of combustion of boron‐RGO composites (46.6∼49.3 kJ ⋅ g−1) measured by oxygen bomb calorimetry was higher than that of the commercial boron NPs (43.4 kJ ⋅ g−1). Upon heating, the boron‐RGO composite begins oxidizing at a lower temperature than the commercial boron particles. A mechanism was proposed for encapsulation of boron NPs with RGO.
Causal mediation analysis with sure outcomes of random events model
Authors: Li Wei , Geng Zhi , Zhou Xiao‐Hua
Published: April 2021

Mediation analysis is a useful tool in randomized trials for understanding how a treatment works, in particular how much of the treatment's effect on an outcome is explained by a mediator variable. The traditional approach to mediation analysis makes sequential ignorability assumption which precludes the existence of unobserved confounders between the mediator and outcome variables. Since the randomized experiment does not randomize the mediator, sequential ignorability may not be plausible. In this article, based on a statistical model termed sure outcomes of random events model, we propose an alternative approach to causal mediation analysis without relying on the sequential ignorability assumption for the case of binary treatment and mediator variables. When the outcome is also binary, we establish the identifiability of the average natural direct and indirect effects in the presence of an unobserved confounder between mediator and outcome variables. More importantly, if the identifiability conditions are violated, we provide new bounds that are narrower than those in the previous studies, and these bound results are extended to the case of an arbitrary bounded outcome. Simulation studies show good performance for the proposed estimators in finite samples. Finally, we use a job training intervention on the mental health study to illustrate our approach.
s‐MoO3/MoO2@C Hollow Tubes as Polysulfide‐Filter for Lithium‐Sulfur Batteries
Authors: Guo Jian , Zhang Jizong , Yang Ting , Zheng Xuewen , Chen Mingming
Published: April 2021

Increasing the active sites to adsorb polysulfides and catalyze its conversion to Li2S/Li2S2 is considered an effective approach to accelerate redox kinetics lithium‐sulfur (Li−S) battery. In this paper, shortened s‐MoO3/MoO2@C hollow tube with abundant adsorption/catalytic active sites is prepared by self‐etching/thermal reduction. Due to the abundant active sites and good Li+ transport of the composite, the redox kinetics of polysulfides is enhanced. Under the condition of 1.56 mg cm−2 of sulfur loading and E/S=12 μL mg−1, the activation energy for Li2S/Li2S2 formation in Li−S cell is reduced to 14.08 kJ mol−1, and the discharging specific capacity remains 488.4 mAh g−1 at 5 C.
Influence of Ethanolic Plant Extracts on Morphology and Size Distribution of Sol‐Gel Prepared TiO2 Nanoparticles
Authors: Rodríguez‐Jiménez Rafael‐Aurelio , Panecatl‐Bernal Yesmin , Carrillo‐López Jesús , Méndez‐Rojas Miguel‐Ángel , Romero‐López Anabel , Pacio‐Castillo Mauricio , Vivaldo Israel , Morales‐Sánchez Alfredo , Arce Roberto D. , Caram Jorge , Villanueva‐Cab Julio , Alvarado Joaquín
Published: April 2021

The influence of ethanolic extracts of three common plants (Equisetum arvense, Syzygium aromaticum and Camellia sinensis) on the morphology and size distribution of TiO2 nanoparticles prepared using the sol‐gel method is presented. The phytochemicals extracted from the plants acted as surfactants, modifying the growth mechanism and stabilizing high‐quality small, quasi‐spherical, non‐aggregated TiO2 nanoparticles with sizes in the range from 20–50 nm. The most satisfactory result was achieved using extracts of E. arvense. The structural, morphological, and optical properties of TiO2 nanoparticles prepared using E. arvense ethanolic extracts are discussed. After thermal treatment at 550 °C, the TiO2 nanoparticles were present only in the anatase crystalline phase, with a bandgap of 3.27 eV, as confirmed by X‐ray diffraction and UV‐vis analyses, respectively. These small morphologically homogeneous TiO2 nanoparticles stabilized by low‐cost, abundant and eco‐friendly capping agents may be useful as components in photovoltaic cells, pharmaceutical and cosmetic products, as well as for photocatalytic uses.
Improving the Cyclic Stability of LiNi0.5Mn1.5O4 Cathode by Modifying the Interface Film with 8‐Hydroxyquinoline
Authors: Shang Huimin , Zhou Hanxiao , Jingjing Gao , Zhang Huan , Li Tianhui , Qiao Yingjun , Niu Wenchao , Qu Meizhen , Xie Zhengwei , Peng Gongchang
Published: April 2021

8‐Hydroxyquinoline (8‐HDQN) is used as a bifunctional film‐forming additive to improve the capacity retention of Li/LiNi0.5Mn1.5O4 (LNMO) cell. Electrochemical analysis and ex‐situ analysis prove that 8‐HDQN can preferentially oxidize on the surface LNMO cathode to modify the Cathode Electrolyte Interface (CEI) film. The modified film effectively reduces the oxidation reaction of the electrolyte and the increase of polarization during the cycle. The CEI film derived from 8‐HDQN also inhibits the dissolution of transition metals ions from the LNMO electrode, and reduces the self‐discharge of the Li/ LNMO cell. Moreover, 8‐HDQN can also reduce the side reaction of PF5 by coordination with PF5 to improve the thermal stability of the electrolyte.
Sunlight Photocatalytic Synthesis of Aryl Hydrazides by Decatungstate‐Promoted Acylation under Room Temperature
Authors: Xie Pan , Shi Sanshan , Hu Xueqing , Xue Cheng , Du Dongdong
Published: April 2021

A sunlight photocatalytic synthesis of aryl hydrazides was achieved via a decatungstate‐promoted addition process of aromatic aldehydes to azo compounds. Aryl hydrazides can be produced in good to excellent yields under room temperature, even if the reaction was carried out as “window ledge” mode. This process is easy to be operated and no additional additives are needed, which makes the practicability and application value increase obviously.
Decentralized secure storage of medical records using Blockchain and IPFS: A comparative analysis with future directions
Authors: Kumar Shivansh , Bharti Aman Kumar , Amin Ruhul
Published: April 2021

Most of the hospitals store their patient's data locally and some even do not have any backup storage. This poses a real threat of data loss or data corruption. Although many hospitals are migrating to cloud storage, the clouds have their own threat vectors. Recently, various health care providers were hit by ransomware and Distributed Denial of Service attacks during the COVID‐19 outbreak. Due to these attacks, many emergency services were halted, affecting hundreds of thousands without any healthcare. Another problem with these traditional database practices is that they often misplace or mix the patient's data, which, needless to say, have severe complications. Many researchers are working on IPFS and Blockchain technology to improve the storage of medical records. This article presents a detailed study of the IPFS and Blockchain based healthcare secure storage solutions. It analyzes the existing solutions and their architecture, which will further facilitate the future research and development of emerging IPFS and Blockchain technologies.
Mitigating distributed denial of service attack: Blockchain and software‐defined networking based approach, network model with future research challenges
Authors: Kumar Shivansh , Amin Ruhul
Published: April 2021

With the rise of technology and easy access to the internet, it is nowadays very easy to perform distributed denial of service (DDoS) attacks. The main target of a DDoS attack is to suspend or interrupt any available services online. It can be done for personal profits or professional reasons, and sometimes over political reasons too. Some of the recent attacks are as follows: the largest ever recorded packet per second based DDoS attack on Akamai servers, the attack on Amazon, and the attacks on the website of the US Department of Health and Human Services. Cutting‐edge technology like Blockchain and software‐defined networking (SDN) are very helpful in developing a mitigating architecture with their collaborative approach, where SDN can authenticate the legitimate IP address and Blockchain can help to store the legitimate user in the trust list with a complex architecture of different assistant Blockchain. This paper proposes three different network architectures for the protection of DDOS attack by enabling Blockchain technology with SDN concept.
Agriculture and Wetland Applications
Authors: Lopez-Sanchez J. M. , Ballester-Berman J. D. , Vicente-Guijalba F. , Cloude S. R. , McNairn H. , Shang J. , Skriver H. , Jagdhuber T. , Hajnsek I. , Pottier E. , Marechal C. , Hubert-Moy L. , Corgne S. , Wdowinski S. , Touzi R. , Gosselin G. , Brooks R. , Yamaguchi Y. , Singh G.
Published: April 2021

Based on experimental results, this chapter describes applications of SAR polarimetry to extract relevant information on agriculture and wetland scenarios by exploiting differences in the polarimetric signature of different scatterers, crop types and their development stage depending on their physical properties. Concerning agriculture, crop type mapping, soil moisture estimation and phenology estimation are reviewed, as they are ones with a clear benefit of full polarimetry over dual or single polarimetry. For crop type mapping, supervised or partially unsupervised classification schemes are used. Phenology estimation is treated as a classification problem as well, by regarding the different stages as different classes. Soil moisture estimation makes intensive use of scattering models, in order to separate soil and vegetation scattering and to invert for soil moisture from the isolated ground component. Then, applications of SAR polarimetry to wetland monitoring are considered that include the delineation of their extent and their characterisation by means of polarimetric decompositions. In the last section of the chapter, the use of a SAR polarimetric decomposition is shown for the assessment of the damages consequential to earthquakes and tsunamis.
What are markets? Selected market theories under genuine uncertainty in comparison
Authors: Schmiel Ute , Sander Hendrik
Published: April 2021

Since market economies are the dominant form of regulating economic action all over the world, the question arises how markets are conceived theoretically. Answering this is relevant because we need to know how existing and hypothetical markets work in general, what they “can do”, and how one can improve the market order. There are three different market approaches that consider genuine uncertainty. According to the new institutional economics approach, markets are institutions that increase boundedly rational actors’ utility. The markets-as-institutional-arrangements approach denies that markets maximize or minimize market outcomes and argues that they enable harmony between individual and common interests. According to the political-cultural approach, markets are political arenas with conflicts between the relevant actors. Deciding reasonably for a theory requires answering whether one theory is more adequate than another. Since literature has not answered this so far, the present paper deals with this issue from a critical-rationalist perspective. It finds that the institutional economics approach is not adequate because its assumptions contradict reality and each other. In contrast, the markets-as-institutional-arrangements approach and the political-cultural approach fulfill critical-rationalist requirements. Therefore, the paper compares them and finds that there are reasons to prefer the political-cultural approach and to interpret the markets-as-institutional-arrangements approach as its special case. Referring to the political-cultural approach has different consequences for analyzing and improving the market order. Taking a political-cultural view implies, e.g., not only focusing on desirable social values and market rules but also on the relevance of interpretative frameworks and power.
Tame torsion and the tame inverse Galois problem
Authors: Bisatt Matthew , Dokchitser Tim
Published: April 2021

Fix a positive integer g and a squarefree integer m. We prove the existence of a genus g curve $$C/{\mathbb {Q}}$$

C
/
Q

such that the mod m representation of its Jacobian is tame. The method is to analyse the period matrices of hyperelliptic Mumford curves, which could be of independent interest. As an application, we study the tame version of the inverse Galois problem for symplectic matrix groups over finite fields.
Modal conversion of transverse mode-locked laser beams
Authors: Schepers Florian , Fallnich Carsten
Published: April 2021

The conversion of transverse mode-locked (TML) laser beams from a Hermite-Gaussian (HG) to a Laguerre-Gaussian (LG) mode set using a cylindrical lens mode converter was demonstrated experimentally. By changing the spatial symmetry of the beams new spatio-temporal dynamics for TML lasers were enabled. In particular, the fast linear motion of an oscillating laser spot, generated by a TML laser based on HG modes, was translated into the circular motion of a TML laser beam based on LG modes. The mode conversion was demonstrated successfully for different average mode orders. Apart from an average ellipticity of about $$6\%$$

6
%

, the converted beam profiles remained circular over the propagation from the near- into the far-field. The remaining ellipticity seemed to be introduced by astigmatism of the incident HG TML beam, which could be compensated before conversion. Due to their radial symmetry and high scanning speed TML laser beams based on LG modes are well suited for precision applications like STED or Minflux microscopy.
Evaluation of stereoacuity with a digital mobile application
Authors: Bonfanti Silvia , Gargantini Angelo , Esposito Gabriele , Facchin Alessio , Maffioletti Marta , Maffioletti Silvio
Published: April 2021

Purpose

Stereopsis is a fundamental skill in human vision and visual actions. There are many ways to test and quantify stereoacuity: traditional paper and new digital applications are both valid ways to test the stereoacuity. The aim of this study is to compare the results obtained using standard tests and the new Stereoacuity Test App developed by the University of Bergamo.

Methods

A group of 497 children (272 males), aged between 6 and 11 years old, were tested using different tests for the quantification of stereopsis at near. These tests were TNO, Weiss EKW, and the new developed Stereoacuity Test App.

Results

A one-way repeated measure ANOVA showed that the three tests give different thresholds of stereoacuity (p < 0.0001). Post hoc analyses with Bonferroni correction showed that all tests showed different thresholds (p < 0.0001). The lower threshold was obtained by Titmus Stereo Test followed by Stereoacuity App, Weiss MKW, and TNO.

Conclusion

The stereoacuity based on global stereopsis showed that the better values were obtained in order by Stereoacuity Test App, TNO, and Weiss EKW. However, the clinical significance of their values is similar. The new digital test showed a greater compliance by the child, showing itself in tune with the digital characteristics of today’s children.
Statistical analysis of the reproducibility of residual stress measurements in cold extruded parts
Authors: Jaeger Fabian , Franceschi Alessandro , Hoche Holger , Groche Peter , Oechsner Matthias
Published: April 2021

Cold extruded components are characterized by residual stresses, which originate from the experienced manufacturing process. For industrial applications, reproducibility and homogeneity of the final components are key aspects for an optimized quality control. Although striving to obtain identical deformation and surface conditions, fluctuation in the manufacturing parameters and contact shear conditions during the forming process may lead to variations of the spatial residual stress distribution in the final product. This could lead to a dependency of the residual stress measurement results on the relative axial and circumferential position on the sample. An attempt to examine this problem is made by the employment of design of experiments (DoE) methods. A statistical analysis of the residual stress results generated through X-Ray diffraction is performed. Additionally, the ability of cold extrusion processes to generate uniform stress states is analyzed on specimens of austenitic stainless steel 1.4404 and possible correlations with the pre-deformed condition are statistically examined. Moreover, the influence of the coating, consisting of oxalate and a MoS2 based lubricant, on the X-Ray diffraction measurements of the surface is investigated.
A learning robot for cognitive camera control in minimally invasive surgery
Authors: Wagner Martin , Bihlmaier Andreas , Kenngott Hannes Götz , Mietkowski Patrick , Scheikl Paul Maria , Bodenstedt Sebastian , Schiepe-Tiska Anja , Vetter Josephin , Nickel Felix , Speidel S. , Wörn H. , Mathis-Ullrich F. , Müller-Stich B. P.
Published: April 2021

Background

We demonstrate the first self-learning, context-sensitive, autonomous camera-guiding robot applicable to minimally invasive surgery. The majority of surgical robots nowadays are telemanipulators without autonomous capabilities. Autonomous systems have been developed for laparoscopic camera guidance, however following simple rules and not adapting their behavior to specific tasks, procedures, or surgeons.

Methods

The herein presented methodology allows different robot kinematics to perceive their environment, interpret it according to a knowledge base and perform context-aware actions. For training, twenty operations were conducted with human camera guidance by a single surgeon. Subsequently, we experimentally evaluated the cognitive robotic camera control. A VIKY EP system and a KUKA LWR 4 robot were trained on data from manual camera guidance after completion of the surgeon’s learning curve. Second, only data from VIKY EP were used to train the LWR and finally data from training with the LWR were used to re-train the LWR.

Results

The duration of each operation decreased with the robot’s increasing experience from 1704 s ± 244 s to 1406 s ± 112 s, and 1197 s. Camera guidance quality (good/neutral/poor) improved from 38.6/53.4/7.9 to 49.4/46.3/4.1% and 56.2/41.0/2.8%.

Conclusions

The cognitive camera robot improved its performance with experience, laying the foundation for a new generation of cognitive surgical robots that adapt to a surgeon’s needs.
Neural substrates involved in the cognitive information processing in teleost fish
Authors: Calvo R. , Schluessel V.
Published: April 2021

Over the last few decades, it has been shown that fish, comprising the largest group of vertebrates and in many respects one of the least well studied, possess many cognitive abilities comparable to those of birds and mammals. Despite a plethora of behavioural studies assessing cognition abilities and an abundance of neuroanatomical studies, only few studies have aimed to or in fact identified the neural substrates involved in the processing of cognitive information. In this review, an overview of the currently available studies addressing the joint research topics of cognitive behaviour and neuroscience in teleosts (and elasmobranchs wherever possible) is provided, primarily focusing on two fundamentally different but complementary approaches, i.e. ablation studies and Immediate Early Gene (IEG) analyses. More recently, the latter technique has become one of the most promising methods to visualize neuronal populations activated in specific brain areas, both during a variety of cognitive as well as non-cognition-related tasks. While IEG studies may be more elegant and potentially easier to conduct, only lesion studies can help researchers find out what information animals can learn or recall prior to and following ablation of a particular brain area.
Risk of early failure of VP shunts implanted for hydrocephalus after craniotomies for brain tumors in adults
Authors: Hosainey Sayied Abdol Mohieb , Hald John K. , Meling Torstein R.
Published: April 2021

Risks and survival times of ventriculoperitoneal (VP) shunts implanted due to hydrocephalus after craniotomies for brain tumors are largely unknown. The purpose of this study was to determine the overall timing of VP shunting and its failure after craniotomy for brain tumors in adults. The authors also wished to explore risk factors for early VP shunt failure (within 90 days). A population-based consecutive patient cohort of all craniotomies for intracranial tumors leading to VP shunt dependency in adults (> 18 years) from 2004 to 2013 was studied. Patients with pre-existing VP shunts prior to craniotomy were excluded. The survival time of VP shunts, i.e., the shunt longevity, was calculated from the day of shunt insertion post-craniotomy for a brain tumor until the day of shunt revision requiring replacement or removal of the shunt system. Out of 4774 craniotomies, 85 patients became VP shunt-dependent (1.8% of craniotomies). Median time from craniotomy to VP shunting was 1.9 months. Patients with hydrocephalus prior to tumor resection (N = 39) had significantly shorter time to shunt insertion than those without (N = 46) (p < 0.001), but there was no significant difference with respect to early shunt failure. Median time from shunt insertion to shunt failure was 20 days (range 1–35). At 90 days, 17 patients (20%) had confirmed shunt failure. Patient age, sex, tumor location, primary/secondary craniotomy, extra-axial/intra-axial tumor, ventricular entry, post-craniotomy bleeding, and infection did not show statistical significance. The risk of early shunt failure (within 90 days) of shunts after craniotomies for brain tumors was 20%. This study can serve as benchmark for future studies.
General information spaces: measuring inconsistency, rationality postulates, and complexity
Authors: Grant John , Parisi Francesco
Published: April 2021

AI systems often need to deal with inconsistent information. For this reason, since the early 2000s, some AI researchers have developed ways to measure the amount of inconsistency in a knowledge base. By now there is a substantial amount of research about various aspects of inconsistency measuring. The problem is that most of this work applies only to knowledge bases formulated as sets of formulas in propositional logic. Hence this work is not really applicable to the way that information is actually stored. The purpose of this paper is to extend inconsistency measuring to real world information. We first define the concept of general information space which encompasses various types of databases and scenarios in AI systems. Then, we show how to transform any general information space to an inconsistency equivalent propositional knowledge base, and finally apply propositional inconsistency measures to find the inconsistency of the general information space. Our method allows for the direct comparison of the inconsistency of different information spaces, even though the data is presented in different ways. We demonstrate the transformation on four general information spaces: a relational database, a graph database, a spatio-temporal database, and a Blocks world scenario, where we apply several inconsistency measures after performing the transformation. Then we review so-called rationality postulates that have been developed for propositional knowledge bases as a way to judge the intuitive properties of these measures. We show that although general information spaces may be nonmonotonic, there is a way to transform the postulates so they can be applied to general information spaces and we show which of the measures satisfy which of the postulates. Finally, we discuss the complexity of inconsistency measures for general information spaces.
A Little Bit of Classical Magic to Achieve (Super-)Quantum Speedup
Authors: Kaszlikowski Dagomir , Kurzyński Paweł
Published: April 2021

We introducenebit, a classical bit with a signed probability distribution. We study its properties and basic transformations that can be applied to it. Then, we introduce a simple dynamical model – a classical random walk supplemented with nebits. We show that such a model exhibits some counterintuitive non-classical properties and that it can achieve or even exceed the speedup of Grover’s quantum search algorithm. The proposed classical dynamics never reveals negativity of nebits and thus we do not need any operational interpretation of negative probabilities. We argue that nebits can be useful as a measure of non-classicality as well as a tool to find new quantum algorithms.