bluuebunny/crossref_metadata_2025_split huggingface dataset:
Metformin is associated with favorable outcomes in patients with COVID-19 and type 2 diabetes mellitus
Authors: Ma Zhiyuan , Patel Nishit , Vemparala Pranathi , Krishnamurthy Mahesh 
Published: April 2022

AbstractCoronavirus disease 2019 (COVID-19) is a new pandemic the entire world is facing since December of 2019. Several risk factors are identified in developing severe disease and one of which is preexisting type 2 diabetes mellitus. Metformin is known to have host-directed anti-viral and anti-inflammatory properties. However, whether these effects offer lower mortality remains unclear. In this retrospective study, we aim to address whether metformin use prior to admission decreases mortality in patients with COVID-19 and pre-existing type 2 diabetes mellitus. A total of 1356 hospitalized patients with COVID-19 and pre-existing type 2 diabetes mellitus was analyzed by multivariable regression. Covariates that potentially confound the association were further adjusted using propensity score matching or inverse probability of treatment weighting. We found that metformin therapy prior to admission in patients with COVID-19 and type 2 diabetes mellitus was significantly associated with less primary outcome events including in-hospital mortality and hospice care enrollment with an odds ratio (OR) of 0.25 (95% CI 0.06–0.74) and less in-hospital length of stay, compared to the non-metformin group. Our results provide supporting evidence that metformin may confer increased survival in patients with COVID-19 and type 2 diabetes mellitus treated with metformin prior to hospitalization.
Characterizing North Carolina's Deaf and Hard of Hearing Infants and Toddlers: Predictors of Vocabulary, Diagnosis, and Intervention
Authors: Campbell Erin , Bergelson Elika 
Published: April 2022

Purpose:
This study sought to (a) characterize the demographic, audiological, and intervention variability in a population of Deaf and Hard of Hearing (DHH) children receiving state services for hearing loss; (b) identify predictors of vocabulary delays; and (c) evaluate factors influencing the success and timing of early identification and intervention efforts at a state level.

Method:
One hundred DHH infants and toddlers (aged 4–36 months) enrolled in early intervention completed the MacArthur–Bates Communicative Development Inventories, and detailed information about their audiological and clinical history was collected. We examined the influence of demographic, clinical, and audiological factors on vocabulary outcomes and early intervention efforts.

Results:
We found that this sample showed spoken language vocabulary delays (production) relative to hearing peers and showed room for improvement in rates of early diagnosis and intervention. These delays in vocabulary and early support services were predicted by an overlapping subset of hearing-, health-, and home-related variables.

Conclusions:

In a diverse sample of DHH children receiving early intervention, we identify variables that predict delays in vocabulary and early support services, which reflected
both
dimensions that are immutable, and those that clinicians and caretakers can potentially alter. We provide a discussion on the implications for clinical practice.

Supplemental Material:

https://doi.org/10.23641/asha.19449839
Deep image retrieval using artificial neural network interpolation and indexing based on similarity measurement
Authors: Ahmad Faiyaz 
Published: April 2022

AbstractIn content‐based image retrieval (CBIR), primitive image signatures are critical because they represent the visual characteristics. Image signatures, which are algorithmically descriptive and accurately recognized visual components, are used to appropriately index and retrieve comparable results. To differentiate an image in the category of qualifying contender, feature vectors must have image information's like colour, objects, shape, spatial viewpoints. Previous methods such as sketch‐based image retrieval by salient contour (SBIR) and greedy learning of deep Boltzmann machine (GDBM) used spatial information to distinguish between image categories. This requires interest points and also feature analysis emerged image detection problems. Thus, a proposed model to overcome this issue and predict the repeating pattern as well as series of pixels that conclude similarity has been necessary. In this study, a technique called CBIR‐similarity measure via artificial neural network interpolation (CBIR‐SMANN) has been presented. By collecting datasets, the images are resized then subject to Gaussian filtering in the pre‐processing stage, then by permitting them to the Hessian detector, the interesting points are gathered. Based on Skewness, mean, kurtosis and standard deviation features were extracted then given to ANN for interpolation. Interpolated results are stored in a database for retrieval. In the testing stage, the query image was inputted that is subjected to pre‐processing, and feature extraction was then fed to the similarity measurement function. Thus, ANN helps to get similar images from the database. CBIR‐SMANN have been implemented in the python tool and then evaluated for its performance. Results show that CBIR‐SMANN exhibited a high recall value of 78% with a minimum retrieval time of 980 ms. This showed the supremacy of the proposed model was comparatively greater than the previous ones.
Advanced orthogonal opposition‐based learning‐driven dynamic salp swarm algorithm: Framework and case studies
Authors: Wang Zongshan , Ding Hongwei , Yang Jingjing , Wang Jie , Li Bo , Yang Zhijun , Hou Peng 
Published: April 2022

AbstractSalp swarm algorithm (SSA) is a relatively new bio‐inspired meta‐heuristic optimization algorithm that mimics the navigating and foraging behavior of salps in oceans. This paper presents an orthogonal quasi‐opposition‐based learning‐driven dynamic SSA (OBDSSA) for solving global optimization problems. The proposed methodology integrates orthogonal quasi‐opposition‐based learning (OQOBL) tactic and dynamic learning (DL) strategy with SSA to improve its performance. The OQOBL technique is used to enrich the exploration and development capability of the canonical SSA to help the salp chain jump out of local optimum, while the DL mechanism is applied to the basic approach to expand the neighborhood searching capabilities of the search agents. To investigate the proposed operators and OBDSSA algorithm, 18 widely used benchmark functions and parameter extraction problem of photovoltaic (PV) model have been experimented upon. The comparisons reveal that OBDSSA outperforms all competitors, including the standard SSA, SSA variants, and other state‐of‐the‐art algorithms. Finally, the developed approach is applied to path planning and obstacle avoidance (PPOA) tasks in autonomous mobile robots (AMR) and satisfactory results are obtained.
Event‐triggered H∞$\mathcal {H}_\infty$ synchronization of directed and switched coupled stochastic delayed neural networks with multi‐weights
Authors: Lin Shanrong , Liu Xiwei , Huang Yanli 
Published: April 2022

AbstractThis essay is devoted to studying synchronization problem of directed and switched coupled stochastic delayed neural networks with multi‐weights (SCSDNNMWs) via designing a novel event‐triggered protocol. The proposed model is based on stochastic delayed neural network with directed coupling, and multiple coupling matrices with switching express intricate and changing communication channels. Since the external disturbances are likely to cause network topologies change, fixed and accurate values of coupling matrices are difficult to obtain, while the above model has more advantages of characterizing this real network. Besides, zero eigenvalue of different coupling matrices are represented by the corresponding normalized left eigenvectors (NLEVec), which is hard to establish yet especially when designing necessary Lyapunov functions. The authors' essay deduces that if the Chebyshev distance among NLEVec of multiple coupling matrices is less than a permissible deviation limit based on a weighted set of these NLEVec, then several event‐triggered synchronization and synchronization criteria are established. The effectiveness of these results are verified by several given examples.
An equilibrium‐based model to investigate market performance of power‐based electricity market
Authors: Rahmati Iman , Akbari Foroud Asghar 
Published: April 2022

AbstractThe conventional model of the day‐ahead electricity markets employs an energy‐based approach to manage the competition among the players. Under this format, it is assumed that everything (including the demand and output power of the generating units) is constant during each hour. This assumption greatly simplifies the market, and it is widely incorporated over the globe. However, it leads to mismatches in the real‐time operation. With the increase in the share of intermittent sources, such mismatches get higher amplitude and become more threatening for market performance and system security. Power‐based modelling of the electricity market (PbM), which has been introduced as a remedy to eliminate mismatches in real‐time operation, has been scrutinized. The previous comparisons between the conventional model and PbM generally deploy a rigid approach based on the existence of perfect competition. They assume that all the generation companies offer their maximum capacity and marginal cost into the market. Moreover, they model a single‐side auction in which only the supply side is actively involved in the market. In order to develop the previous studies on PbM, an equilibrium environment to model the players’ interactions within a competitive market has been employed. Employment of an equilibrium model brings the benefits of modelling a double‐side market and can simulate the strategic behaviour of the market players on both sides within a partially competitive electricity market. The equilibrium model provides empirical insight on how changing the market structure to PbM affects players’ behaviour and shifts the market equilibrium and provided some unreported attributes of PbM. The study is based on a real‐world network of the Gilan province in northern Iran.
Special transformer sharing mode: Utilizing special transformers of buildings to supply power for charging stations
Authors: Zhang Yongjun , Yang Jingxu , Li Qinhao , Deng Wenyang , Xie Xiaoyu 
Published: April 2022

AbstractIn view of the limited capacity for public transformers to accept electric vehicles (EVs) and the large cost of putting in new transformers to supply power in the parking lot of urban buildings, a special transformer sharing mode (STSM) is proposed, where charging station operators utilize the special transformers of buildings to supply power for charging stations. To enhance the applicability of STSM, single regulation and joint regulation methods for the charging price strategy of charging stations are put up, and the mathematical model of joint regulation is focused on. First of all, a joint regulation mechanism is established, in which EVs are guided to charge off‐peak and off‐station through the joint regulation. Secondly, integrating charging fees, queuing costs, and transfer costs, the equivalent charging prices for EV users are put forward. Based on the difference of the equivalent charging prices, transfer probability model for EVs’ charging periods and charging stations is proposed. Furthermore, the overall objective of joint regulation is built based on the net income of all parties. And an optimization method for the joint regulation of charging prices is proposed. Then, regulation lifting ratio is put forward to reflect the superiority of joint regulation over single regulation. Based on this, an evaluation model for joint station diameter threshold is established. The practical result proves that through single regulation and joint regulation, approximately 200–500 additional EVs can be powered, which will result in significant savings in infrastructure construction and investment costs.
A new passive islanding detection technique for a microgrid based on transient energy
Authors: Hasan Saady , Saleh Sherif S. 
Published: April 2022

AbstractA new passive islanding detection technique based on transient energy that is measured and analysed at targeted distributed generation (DG) or the point of common coupling (PCC) is presented. The proposed technique measures the superimposed components and then calculates the transient active energy (TAE) and the transient reactive energy (TRE). Using the relation between TAE and the TRE, the relay can determine the islanding situation even in a worst‐case operational scenario, and this is a notably shorter response time according to the current standards. The performance of the proposed technique is simulated in the MATLAB environment. Islanding and non‐islanding scenarios for different power match conditions and types of DGs are simulated. The evaluation of the simulation results shows that the proposed technique identifies the islanding with a less than zero power mismatch, operates accurately under the condition of load variation, and does not conflict with the power system operation during normal conditions. It removes the passive technique drawbacks by having a tiny non‐detection zone (NDZ) and a faster response.
Improvement of voltage adaptability for decentralised doubly‐fed induction generator wind power system based on nine‐switch converter
Authors: Hu Zhishuai , Ren Yongfeng , He Jinwei , Xue Yu , Yun Pingping 
Published: April 2022

AbstractThis paper proposes a method to improve the voltage adaptability of doubly fed induction generator (DFIG) wind turbines in a decentralised scenario by incorporating a nine‐switch converter (NSC). With the proposed scheme, the DFIG can realise low voltage ride‐through (LVRT) and continuous operation under the grid voltage harmonic, drop, and rise. The topology of the NSC‐DFIG system is introduced and is used to solve the circuit model. Control strategies for voltage compensation and current compensation are based on the circuit model. The corresponding voltage compensation scheme and the NSC DC voltage control scheme were designed according to the specific capacity configuration of the NSC in this study. To reduce the DC‐side voltage of the NSC, a third harmonic‐injection modulation method and a dynamic modulation ratio allocation strategy were incorporated. Simulations under four power grid voltage conditions were used to validate the scheme. This method can improve the voltage adaptability for decentralised DFIG wind power systems, which can enable their successful interactions with the power grid.
Multi‐target pair‐matching method based on angle information in transmit/receive‐receive synergetic High Frequency Surface Wave Radar
Authors: Bai Yang , Wu Xiaochuan , Deng Weibo , Zhang Xin 
Published: April 2022

AbstractIn the past few decades, the target location methods in transmit/receive‐receive (T/R‐R) synergetic High Frequency Surface Wave Radar (HFSWR) have received extensive attention from the signal processing community. However, there are few studies on the method of parameter pair‐matching for multi‐target scene. In this paper, a computationally efficient multi‐target pair‐matching method based on angle information only in T/R‐R synergetic HFSWR is developed. The proposed method is realised by dealing with three vectors composed of the first column, the first row and diagonal entries of the correlation matrix, instead of performing the singular value decomposition (SVD) of the correlation matrix. Simultaneously, the proposed method is a computationally efficient subspace algorithm, which only uses the angle information to complete the purpose of multi‐target pair‐matching. The simulation results are presented to demonstrate the effectiveness of the proposed method.
Women’s work on small change: privately issued currency by women in mid-17th century London
Authors: Ben-Or Idit 
Published: April 2022

AbstractThis paper focuses on privately issued currencies by women in mid-17th century London. These currencies appeared across England as part of a large wave of minting which began during the English Civil War as a result of severe shortages of low value coinage (‘small change’), used for purposes of petty trade. In London alone over 4200 tradesmen and businesses issued tokens, only around 140 of these issuers were women. The tokens are a rare visual and material source on the daily life of working women and their self-representation. By contextualizing the issuers’ occupations and token designs within the history of women’s legal status, this paper will demonstrate that token issuers were likely not under the status of married women. The paper examines who these women issuers were, their occupations, and the legal status that enabled them to become independent active agents within the new commercial sphere of tokens. The paper will demonstrate that the artifact of tokens issued by women is extraordinary within the phenomenon, though the line of work these women did was not unique in the period. The ability of women to represent themselves on a token was likely a direct result of their legal status and the commercial rights it entailed.
Suppression of ambient temperature-caused drift in a laser power stabilization system with a liquid crystal variable retarder in atomic gyroscopes
Authors: Niu Yue , Duan Lihong , Zhang Jingxin , Huang Jiong , Zhai Yueyang , Quan Wei 
Published: April 2022

Laser power stabilization systems with liquid crystal variable retarders have been employed in miniaturized atomic gyroscopes for the merits of low power consumption and easy integration. However, the long-term power drift of the system output with ambient temperature significantly decreases the long-term performance of atomic gyroscopes. Here, we demonstrated a method of dynamic closed-loop control based on the combination of optical power drift and ambient temperature modeling. For a continuous 45 min operation within an ambient temperature variation range of 23.7–25.3 °C, the relative Allan deviation of the output optical power was decreased by one order of magnitude from 2.29 × 10−4 to 3.35 × 10−5 after 100 s averaging time. The long-term stability of the system was significantly improved. In addition, the scheme requires no additional thermal control device, preventing the introduction of extra electromagnetic interference, which is desirable in a miniaturized atomic gyroscope.
A qPlus-based scanning probe microscope compatible with optical measurements
Authors: Cheng Bowei , Wu Da , Bian Ke , Tian Ye , Guo Chaoyu , Liu Kaihui , Jiang Ying 
Published: April 2022

We design and develop a scanning probe microscope (SPM) system based on the qPlus sensor for atomic-scale optical experiments. The microscope operates under ultrahigh vacuum and low temperature (6.2 K). In order to obtain high efficiency of light excitation and collection, two front lenses with high numerical apertures (N.A. = 0.38) driven by compact nano-positioners are directly integrated on the scanner head without degrading its mechanical and thermal stability. The electric noise floor of the background current is 5 fA/Hz1/2, and the maximum vibrational noise of the tip height is below 200 fm/Hz1/2. The drift of the tip–sample spacing is smaller than 0.1 pm/min. Such a rigid scanner head yields small background noise (oscillation amplitude of ∼2 pm without excitation) and high quality factor (Q factor up to 140 000) for the qPlus sensor. Atomic-resolution imaging and inelastic electron tunneling spectroscopy are obtained under the scanning tunneling microscope mode on the Au(111) surface. The hydrogen-bonding structure of two-dimensional (2D) ice on the Au(111) surface is clearly resolved under the atomic force microscope (AFM) mode with a CO-terminated tip. Finally, the electroluminescence spectrum from a plasmonic AFM tip is demonstrated, which paves the way for future photon-assisted SPM experiments.
Avian diversity and abundance across years: consistent patterns in forests but not grasslands on Viti Levu, Fiji
Authors: Naikatini Alivereti N. , Keppel Gunnar , Brodie Gilianne , Kleindorfer Sonia 
Published: April 2022

Context Habitat loss is a global problem and in Fiji >50% of the land area once covered by forests has been converted to grasslands and agricultural land. About 99% of Fiji’s endemic biodiversity and 80% of the land bird species have been identified as forest species. Aims In this study, we compare forest and grassland sites and test for consistency in avian diversity, abundance, foraging guild, and distribution status (endemic, native, introduced to Fiji) over a 5-year period (2016–2020). Methods We surveyed bird communities using the point count method with a 100 m radius and 7-min observation period per site. Key results A one-way analysis of similarities (ANOSIM) analysis showed significant differences in species composition and bird abundance between the forested habitats and grassland habitats. A general linear model test showed significant differences in foraging guild composition and distribution status between forested and grassland habitats. There were no significant differences between the three forested sites (primary montane forest, secondary old-growth forest, old-growth mahogany plantations with regenerating native species), while grassland sites had stronger annual change in species composition. Implications Forest cover, irrespective of whether these forests are of primary or secondary nature, therefore plays an important role in maintaining the native and endemic land bird species and other biodiversity in oceanic island ecosystems such as Viti Levu Island, Fiji.
Unidirectional mannitol synthesis ofAcinetobacter baumanniiMtlD is facilitated by the helix–loop–helix-mediated dimer formation
Authors: Tam Heng-Keat , König Patricia , Himpich Stephanie , Ngu Ngoc Dinh , Abele Rupert , Müller Volker , Pos Klaas M. 
Published: April 2022

SignificanceMannitol biosynthesis is essential forAcinetobacter baumanniito cope with osmotic stress. Currently, onlyPseudomonas putida,Acinetobacter baylyi, andA. baumanniiare able to de novo synthesize mannitol by a structurally unique bifunctional mannitol-1-phosphate dehydrogenase/phosphatase (AbMtlD). The molecular mechanism of reduction and dephosphorylation of fructose-6-phosphate to mannitol is highly dependent on the substrate shuffling from one protomer to the other protomer by a unique helix–loop–helix domain–mediated dimer formation, thus ensuring unidirectional and efficient biosynthesis of mannitol. These observations support an evolutionary adaptation of AbMtlD by fusion of dehydrogenase and phosphatase domains to facilitate efficient unidirectional enzymatic production of mannitol, unifying regulatory control and minimizing the intracellular concentration of toxic mannitol-1-phosphate during salt stress.