bluuebunny/crossref_metadata_2025_split huggingface dataset:
Assessing the combustibility of claddings: A comparative study of the modified cone calorimeter method and cylindrical furnace test
Authors: Nguyen Kate , Kim Nam Kyeun , Bhattacharyya Debes , Mouritz Adrian 
Published: May 2021

SummaryA cone calorimeter, a standard device to measure the fire reaction properties of materials, is modified in this study to investigate its potential to replace the cylindrical furnace test method to assess the combustibility of cladding materials used in buildings. The modification allows cladding materials to be evaluated under conditions closer to their end‐use configuration than the current testing condition in the cylindrical furnace test. In addition, the modified cone calorimeter method provides more quantitative data on the fire reaction properties of the cladding materials compared to the passed/failed indicator in the cylindrical furnace test. Comparative studies between modified cone calorimeter and cylindrical furnace test results for four types of cladding with different combustibility properties are performed. The surface temperature, time‐to‐ignition, and flaming duration values measured for the claddings using the two test methods are similar, leading to the same classification based on AS 1530.1 standard. Other fire reaction properties of the claddings can be measured using the modified cone calorimeter method, which is not possible with the cylindrical furnace test, including mass loss rate, heat release rate, and smoke production, which are particularly dependent on the formation of a ceramic‐like carbonaceous layer of tested samples.
Connectivity within regions characterizes epilepsy duration and treatment outcome
Authors: Chen Xue , Wang Yanjiang , Kopetzky Sebastian J. , Butz‐Ostendorf Markus , Kaiser Marcus 
Published: May 2021

AbstractFinding clear connectome biomarkers for temporal lobe epilepsy (TLE) patients, in particular at early disease stages, remains a challenge. Currently, the whole‐brain structural connectomes are analyzed based on coarse parcellations (up to 1,000 nodes). However, such global parcellation‐based connectomes may be unsuitable for detecting more localized changes in patients. Here, we use a high‐resolution network (~50,000‐nodes overall) to identify changes at the local level (within brain regions) and test its relation with duration and surgical outcome. Patients with TLE (n = 33) and age‐, sex‐matched healthy subjects (n = 36) underwent high‐resolution (~50,000 nodes) structural network construction based on deterministic tracking of diffusion tensor imaging. Nodes were allocated to 68 cortical regions according to the Desikan–Killany atlas. The connectivity within regions was then used to predict surgical outcome. MRI processing, network reconstruction, and visualization of network changes were integrated into the NICARA (https://nicara.eu). Lower clustering coefficient and higher edge density were found for local connectivity within regions in patients, but were absent for the global network between regions (68 cortical regions). Local connectivity changes, in terms of the number of changed regions and the magnitude of changes, increased with disease duration. Local connectivity yielded a better surgical outcome prediction (Mean value: 95.39% accuracy, 92.76% sensitivity, and 100% specificity) than global connectivity. Connectivity within regions, compared to structural connectivity between brain regions, can be a more efficient biomarker for epilepsy assessment and surgery outcome prediction of medically intractable TLE.
Effect of antioxidant, malondialdehyde, macro‐mineral, and trace element serum concentrations in Bangladeshi patients with schizophrenia: A case‐control study
Authors: Uddin S. M. Naim , Sultana Farhana , Uddin Md. Giash , Dewan Syed Masudur Rahman , Hossain Mohammed Kamrul , Islam Mohammad Safiqul 
Published: May 2021

AbstractBackgroundSchizophrenia (SCZ) is an incurable neuropsychiatric disorder generally described by impaired social behavior and altered recognition of reality. For the first time, this study explored serum levels of antioxidants (vitamin A, E, and C), malondialdehyde (MDA), macro‐minerals (calcium, potassium, and sodium), and trace elements (zinc, iron, and selenium) in Bangladeshi patients with SCZ and thereby, discovering any pathophysiological correlation.MethodsThis case‐controlled study evaluated 63 patients with SCZ as cases and 63 healthy individuals as controls. Vitamin A and E levels were defined by RP‐HPLC. MDA and vitamin C levels were measured by using UV spectrophotometry, and macro and trace elements by atomic absorption spectroscopy.ResultsThis study found significantly (P ≤ 0.05) elevated MDA levels and decreased levels of antioxidants—vitamin A, C, and E and significantly (P ≤ 0.05) diminished levels of macro and trace elements in cases in contrast to the controls. Serum levels of zinc (Zn), selenium (Se), iron (Fe), potassium (K), calcium (Ca), and sodium (Na) were determined to be 0.33 ± 0.008, 0.0252 ± 0.00060, 0.24 ± 0.01, 64.18 ± 2.72, 36.88 ± 2.56, and 2657.5 ± 53.32 mg/L, respectively, in cases, whereas 0.79 ± 0.03, 0.0650 ± 0.00355,0.78 ± 0.03, 168.01 ± 2.85, 86.43 ± 2.55, and 3200.8 ± 29.96 mg/L, respectively, were determined in controls. Pearson's correlation analysis revealed a negative correlation between Zn and Na, Zn and K, Zn and Ca, Zn and Fe, Zn and Se, Fe and Na, and Fe and Se in patients.ConclusionsThe findings connect that the pathogenesis of SCZ may have a correlation with altered levels of antioxidants, MDA, macro‐minerals, and trace elements.
Medical image denoising using optimal thresholding of wavelet coefficients with selection of the best decomposition level and mother wavelet
Authors: Benhassine Nasser Edinne , Boukaache Abdelnour , Boudjehem Djalil 
Published: May 2021

AbstractMedical images have become omnipresent in diagnosis and therapy. However, they can be affected by various types of noise that reduce image quality and make the final diagnostic decision difficult. The main objective of this research is to effectively remove the noise while preserving the important image characteristics. This paper proposes a novel approach for image denoising based on discrete wavelet transform (DWT) with the selection of the best decomposition level and mother wavelet. Then, the thresholding function is carried out in the detail coefficients. Optimal thresholding is done using new optimization techniques such as the crow search algorithm and social spider optimization techniques. Finally, the inverse of DWT is applied to reconstruct the denoised image. The proposed method is evaluated using peak signal to noise ratio, mean square error, and the structural similarity index measure. The experimental results show the efficiency of the optimization‐based denoising method over standard methods. Interesting results are obtained with all kinds of noise, and improvements about 30 dB can be reached with the Rician noise.
The Puppeteer behind the scenes: Toward understanding ecosystem leadership mechanisms to grow IoT in South Africa
Authors: Goshalia Chetan , McDonogh Jennifer , Mhlanga Prins , Sewchurran Kosheek 
Published: May 2021

AbstractThe IoT digital revolution has opened opportunities to resolve complex, economic, environmental and social issues. Digitizing efforts involve participating in an ecosystem of innovators, providers, evolving customer needs and government policies. Companies entering this world report experiencing complexities with realizing value for stakeholders. This study presents a critical inquiry into the IoT world in South Africa. A grounded theory methodology is applied to provide an understanding of the important mechanisms at play affecting uptake of IoTs in the ecosystem. We use the insights to develop a model relevant for IoT players and urban planners to enhance benefit realization for the ecosystem as a whole. The study provides insight into a missing, “Puppeteering” role, that is required to organize ecosystem participants in their pursuit of value. A significant finding is that this role is best played by technology owners so that they can co‐create and generate jointly‐developed power to realize potential value for the entire ecosystem. The role needs to synergistically organize ecosystem participants to capture and distribute value to sustainably grow the ecosystem; and to engage in the development of required capabilities to sustain this. We argue that this “puppeteer effect” has potential to foster an inclusive, sustainable IoT strategy.
Alteration of fibrin hydrogel gelation and degradation kinetics through addition of azo dyes
Authors: Gandhi Jarel K , Heinrich Lauren , Knoff David S , Kim Minkyu , Marmorstein Alan D 
Published: May 2021

AbstractFibrin is a degradable biopolymer with an excellent clinical safety profile. Use of higher mechanical strength fibrin hydrogels is limited by the rapid rate of fibrin polymerization. We recently demonstrated the use of higher mechanical strength (fibrinogen concentrations >30 mg/ml) fibrin scaffolds for surgical implantation of cells. The rapid polymerization of fibrin at fibrinogen concentrations impaired our ability to scale production of these fibrin scaffolds. We serendipitously discovered that the azo dye Trypan blue (TB) slowed fibrin gelation kinetics allowing for more uniform mixing of fibrinogen and thrombin at high concentrations. A screen of closely related compounds identified similar activity for Evans blue (EB), an isomer of TB. Both TB and EB exhibited a concentration dependent increase in clot time, though EB had a larger effect. While gelation time was increased by TB or EB, overall polymerization time was unaffected. Scanning electron microscopy showed similar surface topography, but transmission electron microscopy showed a higher cross‐linking density for gels formed with TB or EB versus controls. Based on these data we conclude that addition of TB or EB during thrombin mediated fibrin polymerization slows the initial gelation time permitting generation of larger more uniform fibrin hydrogels with high‐mechanical strength.
Drug‐induced organ injury in coronavirus disease 2019 pharmacotherapy: Mechanisms and challenges in differential diagnosis and potential protective strategies
Authors: Ommati Mohammad Mehdi , Mobasheri Ali , Heidari Reza 
Published: May 2021

AbstractThe world is currently facing an unprecedented pandemic caused by a newly recognized and highly pathogenic coronavirus disease 2019 (COVID‐19; induced by SARS‐CoV‐2 virus), which is a severe and ongoing threat to global public health. Since COVID‐19 was officially declared a pandemic by the World Health Organization in March 2020, several drug regimens have rapidly undergone clinical trials for the management of COVID‐19. However, one of the major issues is drug‐induced organ injury, which is a prominent clinical challenge. Unfortunately, most drugs used against COVID‐19 are associated with adverse effects in different organs, such as the kidney, heart, and liver. These side effects are dangerous and, in some cases, they can be lethal. More importantly, organ injury is also a clinical manifestation of COVID‐19 infection. These adverse reactions are increasingly recognized as outcomes of COVID‐19 infection. Therefore, the differential diagnosis of drug‐induced adverse effects from COVID‐19‐induced organ injury is a clinical complication. This review highlights the importance of drug‐induced organ injury, its known mechanisms, and the potential therapeutic strategies in COVID‐19 pharmacotherapy. We review the potential strategies for the differential diagnosis of drug‐induced organ injury. This information can facilitate the development of therapeutic strategies, not only against COVID‐19 but also for future outbreaks of other emerging infectious diseases.
Using a machine learning model for the optimal design of simulated moving bed processes and its application to separate rebaudioside A and stevioside
Authors: Yao Chuanyi , Zheng Zhenwei , Chen Kuan , Wei Liangwan , Shen Liang , Lu Yinghua , Fan Enguo 
Published: May 2021

AbstractBACKGROUNDSolving a mechanistic model of simulated moving bed (SMB) is extremely time consuming, therefore, it is inefficient for online control using the optimization method based on such a mechanistic model. To this end, the machine learning model can be regarded as a potential substitution to accelerate the optimization process.RESULTSSeveral machine learning algorithms were applied to predict the product purities under various operation conditions using two SMB processes as case studies: i.e., a sugar separation of rebaudioside A and stevioside, as well as an enantioseparation of 1,1′‐bi‐2‐naphthol racemate. The results indicate that the random forest (RF) model and the deep neural network (DNN) model provide a satisfactory accuracy with a mean absolute error (MAE) lower than 0.19% (RF) and 0.08% (DNN), respectively. During the optimization process to maximize the feed flowrate under specific purity requirements, among the two selected models, DNN model showed a better generalization ability than RF model and gave a feed flowrate 10% higher than the highest value in the training dataset, which was consistent with the result obtained by using the mechanistic model. The optimized operation conditions for sugar separation were verified experimentally and the achieved purities of rebaudioside A and stevioside were 99.2% and 98.8%, respectively.CONCLUSIONThe DNN model was successfully used to substitute the mechanistic model to reach a rapid optimization of SMB processes with an improved efficiency of 103 ~ 104 times. © 2021 Society of Chemical Industry (SCI).
HIV risk and pre‐exposure prophylaxis interest among women seeking post‐abortion care in Kenya: a cross‐sectional study
Authors: Heffron Renee , Casmir Edinah , Aswani Linda , Ngure Kenneth , Kwach Benn , Ogello Vallery , Kiptinness Catherine , Ambiyo Faith , Wairimu Njeri , Ossome Ethel , Machafu Hilda , Zia Yasaman , Thomas Dorothy , Scoville Caitlin , Barker Taryn , Bukusi Elizabeth , Mugo Nelly 
Published: May 2021

AbstractIntroductionPost‐abortion clinics located in regions with high HIV burden may ideal locations to integrate counselling and delivery of HIV pre‐exposure prophylaxis (PrEP), aligning with normative goals for integrated delivery of HIV and reproductive health care. The objective of this study was to gauge the degree to which Kenyan women seeking care for a pregnancy loss, including induced abortion, are at risk for HIV and whether women would welcome an introduction to PrEP prior to discharge from post‐abortion care.MethodsWe conducted a mixed‐methods study from August 2019 to February 2020 with women ages 15 to 30 recruited sequentially as they were accessing post‐abortion care at public and private facilities in Thika and Kisumu, Kenya. Data collection was through a cross‐sectional survey and laboratory testing for common sexually transmitted infections (N = 200), and in‐depth interviews (N = 30). Descriptive statistics summarize PrEP knowledge and referrals and a multivariable log‐link binomial model estimated correlates of receiving a referral for PrEP. Qualitative data were analysed using inductive and deductive approaches.ResultsAmong 200 HIV‐negative women (median age 21.0, interquartile range 19.0 to 22.0), the prevalence of Chlamydia trachomatis was 18.2% and Neisseria gonorrhoeae was 2.0%. Half of the women scored ≥5 on a validated tool that would correspond to an expected HIV incidence of 9.5% per year. Approximately half (55.8%) of women were familiar with PrEP prior to the study and 33.3% received a referral from study staff to a clinic offering PrEP. In qualitative interviews, women expressed interest in accessing PrEP from the gynaecology ward that provided post‐abortion care but they preferred alternative locations for PrEP refills.ConclusionsKenyan women accessing post‐abortion care have substantial HIV risk and were favourable about the idea of receiving support to initiate PrEP as part of care offered during post‐abortion care. These settings can be integrated into national PrEP programmes as locations providing PrEP referrals and initiation.
Adherence to event‐driven HIV PrEP among men who have sex with men in Amsterdam, the Netherlands: analysis based on online diary data, 3‐monthly questionnaires and intracellular TFV‐DP
Authors: Jongen Vita W , Hoornenborg Elske , van den Elshout Mark AM , Boyd Anders , Zimmermann Hanne ML , Coyer Liza , Davidovich Udi , Anderson Peter L , de Vries Henry JC , Prins M , Schim van der Loeff Maarten F ,   the Amsterdam PrEP Project team in the HIV Transmission Elimination Amsterdam (H‐TEAM) Initiative
Published: May 2021

AbstractIntroductionEvent‐driven pre‐exposure prophylaxis (edPrEP) with oral tenofovir disoproxil fumarate (TDF)/emtricitabine (FTC) is highly effective for preventing HIV acquisition in men who have sex with men (MSM) and is preferred over daily PrEP by some MSM. However, it is largely unknown how well MSM adhere to edPrEP. We then aimed to assess PrEP protection during CAS among MSM using edPrEP and participating in the Amsterdam PrEP demonstration project (AMPrEP).MethodsWe analysed data from participants enrolled in AMPrEP who were taking edPrEP. We measured adherence through (1) a mobile application in which sexual behaviour and PrEP‐use were recorded daily, (2) three‐monthly self‐completed questionnaires and (3) dried blood spot (DBS) samples collected around six, twelve and twenty‐four months after PrEP initiation. We assessed the proportion of days with condomless anal sex (CAS) acts that were protected by PrEP, per partner type (i.e. steady partners, known casual partners, unknown casual partners), and the proportion of three‐month periods during which PrEP was correctly used. Intracellular TFV‐diphosphate (TFV‐DP) concentrations were determined from DBS. Good adherence was defined as at least one tablet before and one tablet within 48 hours after a CAS act.ResultsBetween 11 September 2015 and 6 October 2019, 182 of 376 MSM (48.4%) used edPrEP for at least one three‐month period. Of the 8224 CAS days that were reported in the app during edPrEP‐use, we observed good protection for most CAS days involving steady partners (n = 1625/2455, 66.9%), known casual partners (n = 3216/3472, 92.6%) and unknown casual partners (n = 2074/2297, 90.3%). Men reported consistently correct PrEP‐use in 851 (81.4%) of the 1046 three‐month periods of edPrEP‐use. The median TFV‐DP concentration was 591 fmol/sample (interquartile range = 270 to 896).ConclusionsAdherence to edPrEP was high as determined from the online app and questionnaire. DBS measurements were consistent with two to three tablets per week on average.
Gadolinium Clearance in the First 5 Weeks After Repeated Intravenous Administration of Gadoteridol, Gadoterate Meglumine, and Gadobutrol to rats
Authors: Bussi Simona , Coppo Alessandra , Bonafè Roberta , Rossi Silvia , Colombo Serra Sonia , Penard Laure , Kirchin Miles A. , Maisano Federico , Tedoldi Fabio 
Published: May 2021

BackgroundStudies of gadolinium (Gd) clearance from animals in the first weeks after administration of gadolinium‐based contrast agents (GBCAs) have previously looked at solitary timepoints only. However, this does not give information on differences between GBCAs and between organs in terms of Gd elimination kinetics.PurposeTo compare Gd levels in rat cerebellum, cerebrum, skin, and blood at 1, 2, 3, and 5 weeks after repeated administration of macrocyclic GBCAs.Study TypeProspective.Animal ModelOne hundred eighty male Sprague–Dawley rats randomized to three groups (n = 60/group), received intravenous administrations of gadoteridol, gadoterate meglumine, or gadobutrol (0.6 mmol/kg for each) four times/week for 5 consecutive weeks. Rats were sacrificed after washout periods of 1, 2, 3, or 5 weeks.Field Strength/SequenceNot applicable.AssessmentCerebellum, cerebrum, skin, and blood were harvested for Gd determination by inductively coupled plasma‐mass spectrometry (15 animals/group/all timepoints).Statistical TestsAnova and Dunnett's test (data with homogeneous variances and normal distribution). Kruskal–Wallis and Wilcoxon's rank sum tests (data showing nonhomogeneous variances or a non‐normal distribution, significance levels: P < 0.05, P < 0.01, and P < 0.001).ResultsGd levels in cerebellum, cerebrum, and skin were significantly lower after gadoteridol than after gadoterate and gadobutrol at all timepoints. Mean cerebellum Gd concentrations after gadoteridol, gadoterate, and gadobutrol decreased from 0.693, 0.878, and 1.011 nmol Gd/g at 1 week to 0.144, 0.282, and 0.297 nmol Gd/g at 5 weeks after injection. Similar findings were noted for cerebrum and skin. Conversely, significantly higher Gd levels were noted in blood after gadoteridol compared to gadobutrol at 1, 2, and 3 weeks and compared to gadoterate at all timepoints.Data ConclusionGadoteridol is eliminated more rapidly from rat cerebellum, cerebrum, and skin compared to gadoterate and gadobutrol in the first 5 weeks after administration, resulting in lower levels of retained Gd in these tissues.Evidence Level1Technical EfficacyStage 5
Neural network model with positional deviation correction for Fourier ptychography
Authors: Zhao Ming , Zhang Xiaohui , Tian Zhiming , Liu Shuai 
Published: May 2021

AbstractFourier ptychography is a new type of computational imaging technology, which uses a stack of low‐resolution images obtained from overlapped apertures (or equivalent) to reconstruct super‐resolved image. However, the accuracy of the aperture position will directly affect the quality and resolution of the reconstructed image. This paper proposes a new perspective for FP positional deviations correction using the neural network. We construct a trainable neural network to perform positional deviations correction along with object reconstruction. The real part and imaginary part of the object as well as the different and irregular positional deviations of each aperture are set as the weights of convolutional layer. The gradients over these weights are computed automatically, and gradient‐based optimization algorithm is employed to recover the object and find the correct aperture position. Simulation and experiment are performed to verify our algorithm. The results show that the proposed algorithm can accurately find the aperture position and improve the reconstruction quality.