Miracle-dz/UniFAR-FTUs huggingface dataset:
The Uptake of Nickel-Titanium Rotary Files in Saudi Arabia

Aim. We surveyed the uptake of nickel-titanium rotary files (NTRFs) among all dentists in Saudi Arabia. Methodology. A questionnaire encompassing endodontic performance and NTRF uptake was e-mailed to all members of the Saudi Dental Society. Data were collected from participants during a three-month period and were analyzed using χ 2 tests and correlation coefficients. Level of significance was set at P = 0.05. Results. The overall response rate was 30.6% (n = 490), and 82.9% were found to perform root canal treatment (RCT). Among the 406 RCT performers, general dentists formed the bulk (45%). Among endodontists, 91.5% were using NTRF (P < 0.001). Those who graduated between 1991 and 2000 used NTRF more than any other group did (78.4%, P = 0.05). Graduates from Europe and Australia used NTRF most frequently (100%, P = 0.001), followed by those from North America (87%, P = 0.001), and finally by Saudi Arabian graduates (68.7%). Male respondents performed more endodontic procedures and used NTRF significantly more often than female respondents did (males: 73%; females: 56.2%) (P = 0.001). The most significant reasons for not using NTRF were “unavailability” (64.7%, P ≤ 0.05) and “lack of experience” (54.1%, P ≤ 0.001). Conclusions. We found that NTRF usage was not as widespread in Saudi Arabia as in other developing countries. Therefore, we suggest an improved implementation of NTRF in undergraduate and postgraduate curriculums and the provision of educational courses with a greater focus on this development.
An empirical study on the persuasiveness of fact-based explanations for recommender systems

Recommender Systems (RS) help users to orientate themselves in large product assortments and provide decision support. Explanations help recommender systems to enhance their impact on users by, for instance, justifying made recommendations. Arguments provide reason in a more structured way, by denoting a conclusion that follows from one or more premises. While expert systems’ explanation have a long tradition in using argumentative patterns, argumentative explanations for recommendations have not yet been systematically researched. This paper compares therefore the persuasion potential of different explanation styles (sentences, facts or argument style) by comparing the robustness of subjects’ preferences when employing an additive utility model from conjoint analysis.
Arterial Spin-Labeled Perfusion of Pediatric Brain Tumors

ASL was used to evaluate 54 children with recently diagnosed brain tumors using a pseudocontinuous technique and blood flow was calculated for all masses. Blood flow was higher in grade 3 and 4 tumors than in lower grade ones. Although ASL was unable to separate tumors by histology, perfusion was found to be higher in medulloblastomas than in pylocytic astrocytomas. BACKGROUND AND PURPOSE: Pediatric brain tumors have diverse pathologic features, which poses diagnostic challenges. Although perfusion evaluation of adult tumors is well established, hemodynamic properties are not well characterized in children. Our goal was to apply arterial spin-labeling perfusion for various pathologic types of pediatric brain tumors and evaluate the role of arterial spin-labeling in the prediction of tumor grade. MATERIALS AND METHODS: Arterial spin-labeling perfusion of 54 children (mean age, 7.5 years; 33 boys and 21 girls) with treatment-naive brain tumors was retrospectively evaluated. The 3D pseudocontinuous spin-echo arterial spin-labeling technique was acquired at 3T MR imaging. Maximal relative tumor blood flow was obtained by use of the ROI method and was compared with tumor histologic features and grade. RESULTS: Tumors consisted of astrocytic (20), embryonal (11), ependymal (3), mixed neuronal-glial (8), choroid plexus (5), craniopharyngioma (4), and other pathologic types (3). The maximal relative tumor blood flow of high-grade tumors (grades III and IV) was significantly higher than that of low-grade tumors (grades I and II) (P < .001). There was a wider relative tumor blood flow range among high-grade tumors (2.14 ± 1.78) compared with low-grade tumors (0.60 ± 0.29) (P < .001). Across the cohort, relative tumor blood flow did not distinguish individual histology; however, among posterior fossa tumors, relative tumor blood flow was significantly higher for medulloblastoma compared with pilocytic astrocytoma (P = .014). CONCLUSIONS: Characteristic arterial spin-labeling perfusion patterns were seen among diverse pathologic types of brain tumors in children. Arterial spin-labeling perfusion can be used to distinguish high-grade and low-grade tumors.
A Census of Optical and Near-Infrared Selected Star-forming and Passively Evolving Galaxies at Redshift z ~ 2

Using the extensive multiwavelength data in the GOODS-North field, including our ground-based rest-frame UV spectroscopy and near-IR imaging, we construct and draw comparisons between samples of optical and near-IR selected star-forming and passively evolving galaxies at redshifts 1.4 ≲ z ≲ 2.6. We find overlap at the 70%-80% level in samples of z ~ 2 star-forming galaxies selected by their optical (UnGℛ) and near-IR (BzK) colors when subjected to common K-band limits. Deep Chandra data indicate a ~25% AGN fraction among near-IR selected objects, much of which occurs among near-IR bright objects (Ks < 20; Vega). Using X-rays as a proxy for the bolometric star formation rate (SFR) and stacking the X-ray emission for the remaining (non-AGN) galaxies, we find that the SFR distributions of UnGℛ, BzK, and J - Ks > 2.3 galaxies (i.e., distant red galaxies; DRGs) are very similar as a function of Ks, with Ks < 20 galaxies having ⟨SFR⟩ ~ 120 M☉ yr-1, a factor of 2-3 higher than those with Ks > 20.5. The absence of X-ray emission from the reddest DRGs and BzK galaxies with (z - K)AB ≳ 3 indicates that they must have declining star formation histories to explain their red colors and low SFRs. While the M/L ratio of passively evolving galaxies may be larger on average, the Spitzer IRAC data indicate that their inferred stellar masses do not exceed the range spanned by optically selected galaxies, suggesting that the disparity in current SFR may not indicate a fundamental difference between optical and near-IR selected massive galaxies (M* > 1011 M☉). We consider the contribution of optical, near-IR, and submillimeter selected galaxies to the star formation rate density (SFRD) at z ~ 2, taking into account sample overlap. The SFRD in the interval 1.4 ≲ z ≲ 2.6 of UnGℛ and BzK galaxies to Ks = 22 and DRGs to Ks = 21 is ~0.10 ± 0.02 M☉ yr-1 Mpc-3. Optically selected galaxies to ℛ = 25.5 and Ks = 22.0 account for ~70% of this total. Greater than 80% of radio-selected submillimeter galaxies to S850 μm ~ 4 mJy with redshifts 1.4 < z < 2.6 satisfy either one or more of the BX/BM, BzK, and DRG criteria.
Correcting Geolocation Errors for Microwave Instruments Aboard NOAA Satellites

Microwave (MW) satellite data are widely used as input in numerical weather prediction models and also in other applications such as climate monitoring and re-analysis. MW satellite data are prone to different problems, including geolocation errors. These data do not have a fine spatial resolution like visible and infrared data; therefore, the accuracy of their geolocation cannot be easily determined using the normal methods such as superimposing coastlines on the satellite images. Currently, no geolocation correction is performed on data from MW instruments aboard the satellites in the National Oceanic and Atmospheric Administration (NOAA) Polar Operational Environmental Satellite program. However, geolocation error can be a significant source of bias in the satellite measurements. In this paper, we investigated and corrected the geolocation errors of the observations from the Advanced Microwave Sounding Unit (AMSU)-A aboard NOAA-15 to NOAA-19, AMSU-B aboard NOAA-15 to NOAA-17, and Microwave Humidity Sounder (MHS) aboard NOAA-18 and NOAA-19. We used the difference between ascending and descending observations along the coastlines to quantify the geolocation errors in terms of the satellite attitudes (Euler angles), i.e., pitch, roll, and yaw. Then, new geographical coordinates and scan/local zenith angles were calculated using new attitudes. The results show that NOAA-15 AMSU-A2 instrument has a mounting error of about 1.2 ° cross-track, and -0.5° along-track, NOAA-16 AMSU-A1 and -A2 instruments have a mounting error of about -0.5° along-track, and NOAA-18 AMSU-A2 instrument has a mounting error of more than -1° along-track.
Passivity Based Stability Condition for Interefered Digital Filters

This paper presents a new passivity condition for fixed-point state-space interfered digital filters using saturation arithmetic. Passivity is a way to characterize input-output stability of a system, that is, supplied bounded input energy produces bounded output energy. The presented criterion also ensures asymptotic stability of the state-space digital filter with zero external disturbances. The result is expressed in terms of linear matrix inequality, and therefore, can be solved via existing numerical packages. A numerical example is arranged to validate the usefulness of the proposed method.
Reallocating and Pricing Illiquid Capital: Two Productive Trees

We develop a two sector general equilibrium model with capital accumulation and convex adjustment costs. We use the model to study capital asset pricing and reallocation, as well as optimal consumption and investment decisions. With two sectors, the consumer balances diversication against the potential productivity and eciency gains of investing more heavily in one sector. The general framework nests and extends standard equilibrium macro-asset pricing models. We show conditions under which aggregates are immune to the distribution of capital and in contrast, when the distribution becomes crucial for both sectoral and aggregate values. Applications of the framework highlight the importance of heterogeneity and capital liquidity - the ability to reallocate capital - for economic growth and asset pricing. Misallocated capital creates risk and reduces utility, but correcting it through capital reallocation reduces eciency and growth.
Evolution of the Cluster Mass Function: Gpc3 Dark Matter Simulations

High-resolution N-body simulations of four popular cold dark matter cosmologies (LCDM, OCDM, QCDM, and tilted SCDM), each containing ~105 clusters of galaxies of mass M1.5 > 5 × 1013 h-1 M☉ in a Gpc3 volume, are used to determine the evolution of the cluster mass function from z = 3 to 0. The large volume and high resolution of these simulations allow an accurate measure of the evolution of cosmologically important (but rare) massive clusters at high redshift. The simulated mass function is presented for cluster masses within several radii typically used observationally (R = 0.5, 1.0, and 1.5 h-1 Mpc, both comoving and physical) in order to enable direct comparison with current and future observations. The simulated evolution is compared with current observations of massive clusters at redshifts 0.3 ≲ z ≲ 0.8. The Ωm = 1 tilted SCDM model, which exhibits very rapid evolution of the cluster abundance, produces too few clusters at z ≳ 0.3 and no massive clusters at z ≳ 0.5, in stark contradiction to observations. The Ωm = 0.3 models—LCDM, OCDM, and QCDM—all exhibit considerably weaker evolution and are consistent with current data. Among these low-density models, OCDM evolves the least. These trends are enhanced at high redshift and can be used to discriminate between flat and open low-density models. The simulated mass functions are compared with the Press-Schechter approximation. Standard Press-Schechter predicts too many low-mass clusters at z = 0, and too few clusters at higher redshift. We modify the approximation by a simple parameterization of the density contrast threshold for collapse, which has a redshift dependence. This modified Press-Schechter approximation provides a good fit to the simulated mass functions.
Bounded influence magnetotelluric response function estimation

Author Posting. © Blackwell, 2004. This article is posted here by permission of Blackwell for personal use, not for redistribution. The definitive version was published in Geophysical Journal International 157 (2004): 988–1006, doi:10.1111/j.1365-246X.2004. 02203.x.
Conserved markers of fetal pancreatic epithelium permit prospective isolation of islet progenitor cells by FACS

Prospective isolation and characterization of progenitor cells is a paradigmatic strategy for studies of organ development. However, extraction of viable cells, fractionation of lineages, and in vitro analysis of progenitors from the fetal pancreas in experimental organisms like mice has proved challenging and has not yet been reported for human fetal pancreas. Here, we report isolation of pancreatic islet progenitor cells from fetal mice by FACS. Monoclonal antibodies that recognize cell-surface proteins on candidate stem cells in brain, skin, and other organs enabled separation of major pancreatic cell lineages and isolation of native pancreatic cells expressing neurogenin 3, an established marker of islet progenitors. New in vitro cell culture methods permitted isolated mouse islet progenitors to develop into hormone-expressing endocrine cells. Insulin-producing cells derived in vitro required or expressed factors that regulate fetal β cell differentiation; thus, the genetic programs normally controlling in vivo mouse islet development are similarly required in our system. Moreover, antibodies that recognize conserved orthologous cell-surface epitopes in human fetal pancreas allowed FACS-based enrichment of candidate islet progenitor cells expressing neurogenin 3. Our studies reveal previously undescribed strategies for prospective purification and analysis of pancreatic endocrine progenitor cells that should accelerate studies of islet development and replacement.
Survival Motor Neuron Protein Regulates Stem Cell Division, Proliferation, and Differentiation in Drosophila

Spinal muscular atrophy is a severe neurogenic disease that is caused by mutations in the human survival motor neuron 1 (SMN1) gene. SMN protein is required for the assembly of small nuclear ribonucleoproteins and a dramatic reduction of the protein leads to cell death. It is currently unknown how the reduction of this ubiquitously essential protein can lead to tissue-specific abnormalities. In addition, it is still not known whether the disease is caused by developmental or degenerative defects. Using the Drosophila system, we show that SMN is enriched in postembryonic neuroblasts and forms a concentration gradient in the differentiating progeny. In addition to the developing Drosophila larval CNS, Drosophila larval and adult testes have a striking SMN gradient. When SMN is reduced in postembryonic neuroblasts using MARCM clonal analysis, cell proliferation and clone formation defects occur. These SMN mutant neuroblasts fail to correctly localise Miranda and have reduced levels of snRNAs. When SMN is removed, germline stem cells are lost more frequently. We also show that changes in SMN levels can disrupt the correct timing of cell differentiation. We conclude that highly regulated SMN levels are essential to drive timely cell proliferation and cell differentiation.
Altruism and agents: an argumentation based approach to designing agent decision mechanisms

We present an argument-based qualitative decision-making frame-work in which the social values promoted or demoted by alternative action-options are explicitly represented. We show how this framework may be used to explain the results of experimental economic studies in which human subjects play the Ultimatum Game, an interaction between two participants in which one player divides a sum of money between them, and the other player may accept or reject the offer. The results of these experiments are not explained by a decision-model assuming the participants are purely self-interested utility-maximizers. Some studies further suggest that differences in choices made in different cultures may reflect their day to day behaviour, which can in turn be related to the values of the subjects, and how they order their values. The decision-framework we propose will aid software engineers designing decision-making mechanisms for autonomous agents, particularly for situations requiring agent adaptability, for example, where agents may prefer different outcome states in transactions involving different types of counter-parties.
Effect of Surgeon Volume on Complications, Length of Stay, and Costs Following Anterior Cervical Fusion

Study Design. Retrospective cohort. Objective. To identify the association between surgeon volume and inpatient complications, length of stay, and costs associated with ACF. Summary of Background Data. Increased surgeon volume may be associated with improved outcomes after surgical procedures. However, there is a lack of information on the effect of surgeon volume on short-term outcomes after anterior cervical fusion (ACF). Methods. A retrospective cohort study of ACF patients was performed using the Nationwide Inpatient Sample (NIS) from 2003 to 2009. Surgeon volume was divided into three categories, volume <25th percentile, 25th to 74th percentile, and ≥75th percentile of surgeon volume. Multivariate regression was used to compare the rates of adverse events, hospital length of stay, and total hospital costs between surgeon volume categories. Results. A total of 419,212 ACF patients were identified. The 25th percentile for volume was 5 cases per year, and the 75th percentile for volume was 67 cases per year. Volume <25th percentile was associated with increased rates of any adverse event (odd ratio, OR 3.8, P < 0.001), and multiple individual complications including death (OR 2.5, P=0.014), myocardial infarction (OR4.4, P < 0.001), sepsis (OR 4.1, P < 0.001), and surgical site infection (OR 4.0, P < 0.001). Notably, volume ≥75th percentile was associated with decreased rates of any adverse event (OR 0.7, P < 0.001) and death (OR 0.6, P = 0.028). On multivariate analysis, length of stay was significantly increased by 2.3 days (P < 0.001) for surgeons <25th percentile of volume and was decreased by 0.3 days for surgeons with volume ≥75th percentile. Hospital costs were $4569 more for surgeons with <25th percentile of volume and $1213 less for surgeons with ≥75th percentile volume. Conclusion. In this nationally representative sample, surgeons with volume <25th percentile had significantly increased complications, length of stay, and costs. Conversely, surgeons with ≥75th percentile volume experienced decreased complications, length of stay, and costs. Level of Evidence: 4
Differential Requirement for Utrophin in the Induced Pluripotent Stem Cell Correction of Muscle versus Fat in Muscular Dystrophy Mice

Duchenne muscular dystrophy (DMD) is an incurable degenerative muscle disorder. We injected WT mouse induced pluripotent stem cells (iPSCs) into mdx and mdx∶utrophin mutant blastocysts, which are predisposed to develop DMD with an increasing degree of severity (mdx <<< mdx∶utrophin). In mdx chimeras, iPSC-dystrophin was supplied to the muscle sarcolemma to effect corrections at morphological and functional levels. Dystrobrevin was observed in dystrophin-positive and, at a lesser extent, utrophin-positive areas. In the mdx∶utrophin mutant chimeras, although iPSC-dystrophin was also supplied to the muscle sarcolemma, mice still displayed poor skeletal muscle histopathology, and negligible levels of dystrobrevin in dystrophin- and utrophin-negative areas. Not only dystrophin-expressing tissues are affected by iPSCs. Mdx and mdx∶utrophin mice have reduced fat/body weight ratio, but iPSC injection normalized this parameter in both mdx and mdx∶utrophin chimeras, despite the fact that utrophin was compromised in the mdx∶utrophin chimeric fat. The results suggest that the presence of utrophin is required for the iPSC-corrections in skeletal muscle. Furthermore, the results highlight a potential (utrophin-independent) non-cell autonomous role for iPSC-dystrophin in the corrections of non-muscle tissue like fat, which is intimately related to the muscle.
Time discretization issues in induction machine model solving for real-time applications

The Euler numerical integration method is used very commonly to solve the dynamic equations of the induction machine in real-time on digital processors. The need to solve the machine model also arises in real-time hardware-in-loop simulations, and in electric load emulation. The Euler method is often preferred in such applications due to its fast, simple single-step, explicit nature. However, Euler integration can result in large errors in transient and steady state response calculations, even with practical integration time steps. This paper aims at providing an analytical approach to studying the steady state errors caused by the Euler method in solving the induction machine model. It is shown analytically that the least error occurs when the machine model is solved in the synchronous reference frame. The effect of these errors on the closed loop decoupled control of induction machines is analysed in detail. The paper also gives a new formulation of Feedback Linearization Control (FLC) in the synchronous reference frame to reduce the effect of the discretization error. Analyses and simulations are validated through experiments.
Event‐weighted proportional hazards modelling for recurrent gap time data

The analysis of gap times in recurrent events requires an adjustment to standard marginal models. One can perform this adjustment with a modified within‐cluster resampling technique; however, this method is computationally intensive. In this paper, we describe a simple adjustment to the standard Cox proportional hazards model analysis that mimics the intent of within‐cluster resampling and results in similar parameter estimates. This method essentially weights the partial likelihood contributions by the inverse of the number of gap times observed within the individual while assuming a working independence correlation matrix. We provide an example involving recurrent mammary tumours in female rats to illustrate the methods considered in this paper. Copyright © 2012 John Wiley & Sons, Ltd.
The ruby type checker

We present the Ruby Type Checker (rtc), a tool that adds type checking to Ruby, an object-oriented, dynamic scripting language. Rtc is implemented as a Ruby library in which all type checking occurs at run time; thus it checks types later than a purely static system, but earlier than a traditional dynamic type system. Rtc supports type annotations on classes, methods, and objects and rtc provides a rich type language that includes union and intersection types, higherorder (block) types, and parametric polymorphism among other features. Rtc is designed so programmers can control exactly where type checking occurs: type-annotated objects serve as the "roots" of the type checking process, and unannotated objects are not type checked. We have applied rtc to several programs and found it to be easy to use and effective at checking types.