Miracle-dz/UniFAR-FTUs huggingface dataset:
Control of instability by injection rate oscillations in a radial Hele-Shaw cell

Small spatial perturbations grow into ﬁngers along the unstable interface of a ﬂuid displacing a more viscous ﬂuid in a porous medium or a Hele-Shaw cell. Mitigating this Saffman-Taylor instability increases the efﬁciency of ﬂuid displacement applications (e.g., oil recovery), whereas amplifying these perturbations is desirable in, e.g., mixing applications. In this work, we investigate the Saffman-Taylor instability through analysis and experiments in which air injected with an oscillatory ﬂow rate outwardly displaces silicone oil in a radial Hele-Shaw cell. A solution for linear instability growth that shows the competing effects of radial growth and surface tension, including wetting effects, is deﬁned given an arbitrary reference condition. We use this solution to deﬁne a condition for stability relative to the constant ﬂow rate case and make initial numerical predictions of instability growth by wave number for a variety of oscillations. These solutions are then modiﬁed by incorporating reference conditions from experimental data. The morphological evolution of the interface is tracked as the air bubble expands and displaces oil between the plates. Using the resulting images, we analyze and compare the linear growth of perturbations about the mean interfacial radius for constant injection rates with and without superimposed oscillations. Three distinct types of ﬂow rate oscillations are found to modulate experimental linear growth over a constant phase-averaged rate of ﬂuid displacement. In particular, instability growth at the interface is mildly mitigated by adding to the base ﬂow rate provided by a peristaltic pump a second ﬂow with low-frequency oscillations of small magnitude and, to a lesser extent, high-frequency oscillations of large amplitude. In both cases, the increased stability results from the selective suppression of the growth of large wave numbers in the linear regime. Contrarily, intermediate oscillations consistently destabilize the interface and signiﬁcantly amplify the growth of the most unstable wave numbers of the constant ﬂow rate case. Numerical predictions of low-frequency oscillations of opposite sign (initially decreasing) show promise of even greater mitigation of linear instability growth than that observed in this investigation. Looking forward, proper characterization of the unsteady, wetting, and nonlinear dynamics of instability growth will give further insight into the efﬁcacy of oscillatory injection rates.
Long-term cultural eutrophication in White and Walden Ponds (Concord, Massachusetts, USA), Thoreau's lakes of light

Abstract Stager JC, Harvey L, Chimileski S. 2020. Long-term cultural eutrophication in White and Walden Ponds (Concord, Massachusetts, USA), Thoreau’s lakes of light. Lake Reserv Manage. XX:XXX–XXX. Two historically important ponds in the vicinity of Boston, MA, were subjected to a comparative paleolimnological investigation of the timing and causes of eutrophication trends in each. The remarkable clarity of White Pond during the early 19th century led Henry David Thoreau to compare it favorably to nearby Walden Pond, but during the 20th century water quality in both ponds declined. Sediment core studies show that cultural eutrophication began at Walden during the 1930s, but no long-term sediment records have been available for White Pond, which makes it more difficult to determine the history and causes of eutrophication there. Here we use microfossil and geochemical analyses of sediment cores to show that major changes in the diatom community of White Pond began around 1900, when fish stocking commenced and soil erosion due to land use in the watershed increased, and that the trend intensified around 1960 and 1990. We also describe efforts to mitigate eutrophication at White Pond, highlight the ecological importance of benthic vegetation in nutrient cycling, and suggest that threats to water quality in both of these ponds will likely increase due to anticipated climatic changes in the region.
Empowering of the teacher’s identity crisis for supporting quality young gifted education

To support good education for young gifted children, needed teachers who have a strong character, in ‎terms of principles, professionalism, and identity. If the teachers who teach these gifted children have ‎weak characters, either because of internal or external factors, then the resulting education is not ‎optimal. One of the important factors that must be considered is the teacher's identity. The topic of ‎empowering teacher's identity in young gifted education has less attention from researchers even ‎though this theme is essential to study. This study aims to determine the problems faced by private ‎school teachers in young gifted education, how it impacts their professional identity crisis, and what ‎strategies proposed to strengthen their identity crisis? Research conducted a qualitative approach. Data ‎were collected through open questionaries distributed to 45 teachers. After data analyzed qualitatively, ‎the researcher goes to choosing 16 teachers involved in the Focus Discussion Group (FGD) for ‎deepening the theme and data validity. This study revealed that teachers of private elementary schools ‎face many problems, which in turn losing their teacher's professional identity. Three types of teachers ‎concerning identity crisis were founded. Most of them vulnerable to change their teacher's professional ‎identity. Strategies to empower their identity crisis as professional teachers proposed. ‎
Diagnostic Accuracy of MRI for Detecting Cervical Invasion in Patients with Endometrial Carcinoma: A Meta-Analysis

Objectives: To evaluate the diagnostic accuracy of magnetic resonance imaging (MRI) in the preoperative assessment of cervical invasion and to analyse the influence of different imaging protocols in patients with endometrial carcinoma. Methods: An extensive search of articles about MRI for assessing cervical invasion in patients with endometrial carcinoma was performed on PubMed, Embase, Web of Science, Cochrane Library, and Clinical Trials from January 2000 to July 2020. Two reviewers independently evaluated the methodological quality of each study by using the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2). Diagnostic accuracy results and additional useful information were extracted. The pooled estimation data was obtained by statistical analysis. Results: A total of 42 eligible studies were included in the meta-analysis. Significant evidence of heterogeneity was found for detecting cervical invasion (I2 = 74.1%, P = 0.00 for sensitivity and I2 = 56.2%, P = 0.00 for specificity). The pooled sensitivity and specificity of MRI were 0.58 and 0.95 respectively. The use of higher field strength (3.0 T) demonstrated higher pooled sensitivity (0.74). Using diffusion weighted imaging (DWI) alone presented higher pooled sensitivity (0.86) than using other sequences. The studies that used dynamic contrast-enhanced MRI (DCE-MRI) alone showed higher sensitivity (0.80) and specificity (0.96) than those that used T2-weighted imaging (T2WI) alone. Conclusions: MRI shows high specificity for detecting cervical infiltration in endometrial carcinoma. Using DWI or a 3.0-T device may improve the pooled sensitivity. DCE-MRI demonstrates higher pooled sensitivity and specificity than T2WI.
PV Waste Thermal Treatment According to the Circular Economy Concept

Photovoltaic panels (PV) are one of the most popular technological solutions used to produce green renewable energy. They are known as green technology, but by analyzing a life cycle of a common panel, we can find out that production of these panels is strictly associated with generation of a large waste stream. PV modules are constantly modified and, therefore, it is required to consider the impact of the applied materials on the environment during the whole lifecycle of the product. The most important aspect of the assessment of a life cycle of a photovoltaic module in the phase of decommissioning is material recycling. The process of material recycling is very difficult, due to the lamination used in the currently exploited technology. This paper presents the results of pyrolysis for a sample of a silicon module. The results of the presented research show a weight loss of 48.16 in case of the tested samples. This paper presents the outcome of a quantitative analysis of the content of polycyclic aromatic for liquid and concentrations of Br, Cl and F for a gaseous fraction of pyrolysis products. The goal of the research presented in the paper was to find the optimal parameters for thermal separation, as well as the influence of the energy consumption and materials separation efficiency on the final thermal efficiency of the process.
Application of Scheimpflug-Based Biomechanical Analyzer and Tomography in Early Detecting of Subclinical Keratoconus in Chinese Patients

PurposeTo evaluate the value of Scheimpflug-based biomechanical analyzer combined with tomography in detecting early keratoconus by distinguishing normal eyes from frank keratoconus (KC) and forme frusta keratoconus (FFKC) eyes in Chinese patients. MethodsThis study included 31 bilateral frank keratoconus patients, 27 unilateral clinical manifest keratoconus patients with very asymmetric eyes, and 79 control subjects with normal corneas. Corneal morphological and biomechanical parameters were measured using the Pentacam HR and Corvis ST (OCULUS, Wetzlar, Germany). The diagnostic capacity of computed parameters reflecting corneal biomechanical and morphological traits [including Belin-Ambrósio deviation index (BAD_D), Corvis biomechanical index (CBI) and tomographic and biomechanical index (TBI)] was determined using receiver operating characteristic (ROC) curves and compared by DeLong test. Additionally, the area under the curve (AUC), the best cutoff values, and Youden index for each parameter were reported. The novel corneal stiffness parameter (Stress-Strain Index or SSI) was also compared between KC, FFKC and normal eyes.ResultsEvery morphological and biomechanical index analyzed in this study was significantly different between KC, FFKC and normal eyes (p=0.000). TBI was most valuable for detecting subclinical keratoconus (FFKC eyes) with an AUC of 0.928 (P=0.000), and any forms of corneal ectasia (FFKC and frank KC eyes) with an AUC of 0.966 (P=0.000). The sensitivity and specificity of TBI for detecting FFKC was 97.5% and 77.8%, for detecting any KC was 97.5% and 89.7%, with a cut-off value of 0.375. Morphological index BAD_D and biomechanical index CBI were also very useful in distinguishing any KC eyes from normal eyes with an AUC of 0.965 and 0.934, respectively. SSI was significantly different between KC, FFKC and normal eyes (P=0.000), indicating an independent decrease in corneal stiffness in KC eyes.Conclusion Combination of Scheimpflug-based biomechanical analyzer and tomography could increase the accuracy of detecting early keratoconus in Chinese patients. TBI was the most valuable index for detecting subclinical keratoconus with high sensitivity and specificity. Evaluation of corneal biomechanical property in refractive surgery candidates is helpful to recognize potential keratoconic eyes and increase surgical safety.
Are more GPs associated with a reduction in emergency hospital admissions? A quantitative study on GP referral in England

Background Recent studies have found an association between access to primary care and accident and emergency attendances, with better access associated with fewer attendances. Analyses of an association with emergency admissions, however, have produced conflicting findings. Aim This study investigated whether emergency admission rates in an area are associated with 1) the number of GPs, and 2) mean size of GP practice. Design and setting Analysis was conducted utilising Hospital Episode Statistics, the numbers of GPs and GP practices, Office for National Statistics population data, Quality and Outcomes Framework prevalence data, and Index of Multiple Deprivation data, from 2004/2005 to 2011/2012, for all practices in England. Method Regression analysis of panel data with fixed effects to address 1) a potential two-way relationship between the numbers of GPs and emergency admissions, and 2) unobservable characteristics of GP practices. Results There is not a statistically significant relationship between the number of GPs in a primary care trust area and the number of emergency admissions, when analysing all areas. In deprived areas, however, a higher number of GPs is associated with lower emergency admissions. There is also a lower emergency admission rate in areas in which practices are on average larger, holding GP supply constant. Conclusion An increase in GPs was found to reduce emergency admissions in deprived areas, but not elsewhere. Areas in which GPs are concentrated into larger practices showed reduced levels of emergency admissions, all else being equal.
RNA-Peptide Conjugation through an Efficient Covalent Bond Formation

Many methods for modification of an oligonucleotide with a peptide have been developed to apply for the therapeutic and diagnostic applications or for the assembly of nanostructure. We have developed a method for the construction of receptor-based fluorescent sensors and catalysts using the ribonucleopeptide (RNP) as a scaffold. Formation of a covalent linkage between the RNA and the peptide subunit of RNP improved its stability, thereby expanding the application of functional RNPs. A representative method was applied for the formation of Schiff base or dihydroxy-morpholino linkage between a dialdehyde group at the 3′-end of sugar-oxidized RNA and a hydrazide group introduced at the C-terminal of a peptide subunit through a flexible peptide linker. In this report, we investigated effects of the solution pH and contribution of the RNA and peptide subunits to the conjugation reaction by using RNA and peptide mutants. The reaction yield reached 90% at a wide range of solution pH with reaction within 3 h. The efficient reaction was mainly supported by the electrostatic interaction between the RNA subunit and the cationic peptide subunit of the RNP scaffold. Formation of the RNP complex was verified to efficiently promote the reaction for construction of the RNA-peptide conjugate.
The Diffusion of Dye Solutions

The apparent diffusion coefficient of congo red in water, obtained by Auerbach-Ostwald’s method, changes with concentration. Solving the Fick’s equation with the assumption that the. diffusion coefficient is a function of concentration, the apparent diffusion coefficient can be recalculated to differential diffusion coefficient. From the value extrapolated to infinite dilution, the particle radius of congo red was calculated using Einstein-Sutherland’s equation. On the assumption that the particle is spherical and not hydrated, the particle weight and association degree were obtained. The diffusion coefficient, obtained by this method for congo red solution containing various concentration of NaCl, agrees well with the data reported by others. With the increase of salt concentration, the particle size increases gradually. No decrease was observed in the particle size with a small addition of electrolyte.
The evolution of knowledge-intensive innovation ecosystems: co-evolving entrepreneurial activity and innovation policy in the West Swedish maritime system

ABSTRACT This paper contributes insights into the debate concerning the emergence of innovation ecosystems. More specifically, we propose a knowledge-intensive innovation ecosystem. Building on prior research on collective action, innovation governance, and knowledge-intensive entrepreneurship, we elaborate on existing theory by presenting a conceptual framework to articulate why ecosystems require the combination of top-down exploration of policy alternatives by policymakers, together with bottom-up knowledge-intensive entrepreneurial activity in order to progress towards sustainable development. Through our case study of the Maritime Cluster of West Sweden, we propose that sustained incentives for knowledge-intensive innovative entrepreneurship, along with more experimentation and new forms of collaboration by policymakers in the Maritime Cluster, are needed in order for progress towards innovation-led sustainable development to occur.
The plasma–sheath boundary: its history and Langmuir's definition of the sheath edge

The introduction of the terms sheath in 1923 and plasma in 1928 by Langmuir is described, followed by their use in the Tonks and Langmuir theory of the positive column at low pressures in 1929. Attention is drawn to the development of Langmuir's ideas during the period from 1923 to 1929. The well-known Bohm criterion for sheath formation, published in 1949, is shown to be closely related to the earlier work of Tonks and Langmuir. The much-used version of the Bohm criterion with the equality sign is obtained by employing the two-scale theory of the plasma and sheath, for the case where λD/L → 0. A generalized Bohm criterion is obtained by introducing the ion velocity distribution; the resulting expression can be understood by considering the propagation of ion-acoustic waves. The plasma–sheath boundary is found to be a sonic surface. Other generalizations of the Bohm criterion are given, including a mixture of positive ions, the presence of negative ions and a non-Maxwellian electron velocity distribution.
The Influence of Procurator Generals in Constitutional Review

After democratic transitions, many Eastern European countries reformed their political institutions in a piecemeal fashion. Focusing on the Bulgarian Constitutional Court from 1992 to 2012 and the Soviet-style procurator general, we analyze how legal reforms operate in practice in transitional societies. Using original data, we find that judges are influenced by the powerful and unaccountable procurator general. Judges’ decisions to strike down laws also are guided by alignment with their or their appointers’ political preferences and the opinions of interested parties in amicus briefs. The study has implications about interbranch relations and the role of procurator generals in constitutional review.
Word2Sent: A new learning sentiment‐embedding model with low dimension for sentence level sentiment classification

Word embedding models become an increasingly important method that embeds words into a high dimensional space. These models have been widely utilized to extract semantic and syntactic features for sentiment analysis. However, using word embedding models cannot be sufficient for sentiment analysis tasks because they do not contain sentiment features. Therefore, word embedding models do not adequately meet the comprehensive needs of sentiment analysis applications that rely on recognizing the polarity of a sentence. In this paper, we propose a sentiment embedding model (Word2Sent model) to tackle the weaknesses of the existing word embedding models for sentiment analysis applications. We developed this model based on the Continuous Bag‐of‐Words model and SentiWordNet lexicon to learn sentiment embedding for each word from its surrounding context words. It preserves semantic and syntactic features and captures implicitly sentiment ones. Besides, it can predict sentiment features in a very low sentiment embeddings dimension than traditional ones. The proposed method provides an improved sentiment classification performance and lowers the computational complexity. Both the accuracy performance and processing time results obtained indicate that the proposed model is particularly promising.
Factors Influencing the adoption of e-commerce by Small and Medium-Sized Enterprises (SMEs) in Algeria: a qualitative study

Small and Medium-sized Enterprises (SMEs) are regarded as the engine of the growth of the world economy. They had recently experienced rapid growth and improved their business activities in terms of customers’ number and revenue expansion when they began to embrace e-commerce and started using it in their business. However, although there is a growing interest in e-commerce, its use is still insufficient in Algeria. Therefore, this study aimed to identify the factors that influence the adoption of e-commerce by SMEs in Algeria. This study adopts a qualitative methodology which involves in-depth, structured interviews to identify the factors that affect SMEs for the adoption of e-commerce in Algeria. The result of research found the main factors hindering the adoption of e-commerce by SMEs in Algeria are the e-payment methods, non-readiness of banks, lack of legal protection and lack in awareness of the benefits of e-commerce, as well as fear of risks. However, some other elements are less significant to influence the adoption of e-commerce. These research findings will give an addition in terms of bringing and giving a chance to the SMEs' leaders and the Algerian economic officials and a clear view of e-commerce practices. This can help them to design a strategy to remove barriers tactfully to its advantage.
Towards ultra-broadband heterodyne interferometry in the N- and Q-bands

For the telescope number and size of the PFI proposal (20 x 8m), the Q-band (around 25 μm) was shown to be an optimal complement to submm- and optical interferometry, to detect substructures in proto-planetary disks. Here, broadband medium-resolution heterodyne would be an appropriate option, considering recent experimental findings on a quantum-limit heterodyne detection (HD) scheme. Under high thermal background and the very small beam filling factors in interferometry, HD was shown to be more sensitive than direct detection for the same bandwidth for wavelengths larger 3-8 micron, depending on the conditions. A new class of heterodyne mixers based on graphene could extend the instantaneous IF-bandwidth up to hundred GHz, for which photonic correlators may be developed since a resolution of R=30000 would be sufficient at 10μm. Such large IF-bandwidths could then even be multiplied in “dispersed heterodyne receivers” using optical frequency combs and photonic techniques derived from the DWDM technology.
An examination of Tunisian fact-checking resources in the context of COVID-19

The study examines the effect of COVID-19 on the fact-checking resources in Tunisia. Through developing monographies, we traced the trajectory of most fact-checking platforms in the Tunisian media and explored their teams and working strategies. We noticed a clear spike in the creation of fact-checking platforms during and after February 2020 and determined that the pandemic created a context in which these platforms emerged and flourished. However, many of these platforms, were a product of journalists' individual initiatives and lacked a clear editorial and strategic inclusion of fact-checking. Besides, we found a lack of prior training and an absence of fact-checkers specialized in science and health communication.