Miracle-dz/UniFAR-FTUs huggingface dataset:
A cascade classifier for diagnosis of melanoma in clinical images

Computer aided diagnosis of medical images can help physicians in better detecting and early diagnosis of many symptoms and therefore reducing the mortality rate. Realization of an efficient mobile device for semi-automatic diagnosis of melanoma would greatly enhance the applicability of medical image classification scheme and make it useful in clinical contexts. In this paper, interactive object recognition methodology is adopted for border segmentation of clinical skin lesion images. In addition, performance of five classifiers, KNN, Naïve Bayes, multi-layer perceptron, random forest and SVM are compared based on color and texture features for discriminating melanoma from benign nevus. The results show that a sensitivity of 82.6% and specificity of 83% can be achieved using a single SVM classifier. However, a better classification performance was achieved using a proposed cascade classifier with the sensitivity of 83.06% and specificity of 90.05% when performing ten-fold cross validation.
Proximal extracranial vertebral artery disease in the New England Medical Center Posterior Circulation Registry.

OBJECTIVE To describe the clinical features of patients with occlusive disease of the proximal (V1) segment of the vertebral artery. DESIGN AND PATIENTS Patients with either occlusion or high-grade stenosis involving the V1 segment were chosen for study from the New England Medical Center Posterior Circulation Registry. The registry is a consecutive series of patients with signs and symptoms of posterior circulation ischemia seen at the New England Medical Center, Boston, Mass, during a 10-year period. Clinical features, radiographic findings, and patient outcome were reviewed. RESULTS Of the 407 patients in the registry, 80 (20%) had V1 segment lesions. Patients could be classified into 5 groups: (1) V1 disease and coexistent severe intracranial occlusive disease of the posterior circulation (n=22); (2) V1 disease with evidence of artery-to-artery embolism (n=19); (3) suspected V1 disease with artery-to-artery embolism, but with other potential causes of stroke or less certain vascular diagnosis (n=20); (4) V1 disease associated with hemodynamic transient ischemic attacks (n=13); and (5) proximal vertebral arterial dissection (n=6). Hypertension, cigarette smoking, and coronary artery disease were common risk factors. Clinical features, location of infarct, and outcome differed between groups and reflected the presumed mechanisms of stroke. CONCLUSIONS Occlusive disease involving the V1 segment of the vertebral artery is common in patients with posterior circulation ischemia, but is often associated with other potential mechanisms of stroke. However, in a series of patients seen at a tertiary referral center, occlusive disease of the V1 segment was the primary mechanism of ischemia in 9% of patients.
Speech intelligibility derived from exceedingly sparse spectral information

Traditional models of speech assume that a detailed auditory analysis of the short-term acoustic spectrum is essential for understanding spoken language. The validity of this assumption was tested by partitioning the spectrum of spoken sentences into 1/3-octave channels ("slits") and measuring the intelligibility associated with each channel presented alone and in concert with the others. Four spectral channels, distributed over the speech-audio range (0.3-6 kHz) are sufficient for human listeners to decode sentential material with nearly 90% accuracy although more than 70% of the spectrum is missing. Word recognition often remains relatively high (60-83%) when just two or three channels are presented concurrently, despite the fact that the intelligibility of these same slits, presented in isolation, is less than 9% (Figure 2). Such data suggest that the intelligibility of spoken language is derived from a compound "image" of the modulation spectrum distributed across the frequency spectrum (Figures 1 and 3). Because intelligibility seriously degrades when slits are desynchronized by more than 25 ms (Figure 4) this compound image is probably derived from both the amplitude and phase components of the modulation spectrum, and implies that listeners' sensitivity to the modulation phase is generally "masked" by the redundancy contained in fullspectrum speech (Figure 5).
Understanding the Role of Rainfall and Hydrology in Determining Fluvial Erosion Efficiency

Due to the challenges in upscaling daily climatic forcing to geological time, physically realistic models describing how rainfall drives fluvial erosion are lacking. To bridge this gap between short‐term hydrology and long‐term geomorphology, we derive a theoretical framework for long‐term fluvial erosion rates driven by realistic climate by integrating an established stochastic‐mechanistic model of hydrology into a threshold‐stochastic formulation of stream power. The hydrological theory provides equations for the daily streamflow probability distribution as a function of climatic boundary conditions. The new parameters introduced are rooted firmly in established climatic and hydrological theory. This allows us to account for how fluvial erosion rates respond to changes in rainfall intensity, frequency, evapotranspiration rates, and soil moisture dynamics in a way that is consistent with existing theories. We use this framework to demonstrate how hydroclimatic conditions and erosion threshold magnitude control the degree of nonlinearity between steepness index and erosion rate. We find that hydrological processes can have a significant influence on how erosive a particular climatic forcing will be. By accounting for the influence of hydrology on fluvial erosion, we conclude that climate is an important control on erosion rates and long‐term landscape evolution.
Politeness strategies in the job application letter: Implications of Intercultural Rhetoric for designing writing feedback

Cet article part du constat que les commentaires d’enseignant qui portent uniquement sur l’erreur grammaticale semblent inefficaces pour aider les etudiants non anglophones a progresser a l’ecrit en anglais. Une conception plus pedagogique des commentaires necessite une meilleure prise en compte du contexte culturel et de la situation du redacteur. S’inscrivant dans le cadre de la Rhetorique Interculturelle, la presente etude examine les lettres de motivation ecrites en anglais par un groupe d’etudiants de langue francaise. L’efficacite des strategies de politesse utilisees dans leurs lettres est evaluee sur deux plans : une analyse lexico-grammaticale des « moves », mais aussi des analyses qualitatives (table ronde, enquete) afin de decrire les dispositifs utilises pour exprimer la politesse. Il ressort qu’enseigner des formules de politesse par la grammaire seule ne constitue pas une aide suffisante pour permettre aux etudiants d’ameliorer leur efficacite a l’ecrit en anglais. Les commentaires d’enseignant, pour etre efficaces, doivent etre multimodaux (oral, ecrit, visuel et comportemental).
CalvinFS: Consistent WAN Replication and Scalable Metadata Management for Distributed File Systems

Existing file systems, even the most scalable systems that store hundreds of petabytes (or more) of data across thousands of machines, store file metadata on a single server or via a shared-disk architecture in order to ensure consistency and validity of the metadata. This paper describes a completely different approach for the design of replicated, scalable file systems, which leverages a high-throughput distributed database system for metadata management. This results in improved scalability of the metadata layer of the file system, as file metadata can be partitioned (and replicated) across a (shared-nothing) cluster of independent servers, and operations on file metadata transformed into distributed transactions. In addition, our file system is able to support standard file system semantics--including fully linearizable random writes by concurrent users to arbitrary byte offsets within the same file--across wide geographic areas. Such high performance, fully consistent, geographically distributed files systems do not exist today. We demonstrate that our approach to file system design can scale to billions of files and handle hundreds of thousands of updates and millions of reads per second-- while maintaining consistently low read latencies. Furthermore, such a deployment can survive entire datacenter outages with only small performance hiccups and no loss of availability.
A Novel HPLC-Assisted Method for Investigation of the Fe2+-Chelating Activity of Flavonoids and Plant Extracts

Flavonoids are a class of natural phenolic compounds that show antioxidant properties. Besides the known mechanisms of action of flavonoids (binding/inactivation of free radicals and other reactive oxygen species) that determine this effect, an important factor is their ability to bind transition metal ions. In this paper, we used a HPLC method with a prechromatographic reaction of a sample with Fe2+ ions (FeCA-HPLC) to characterize the Fe2+-chelating properties of individual compounds, their mixtures, and plant extracts. Using two classes of flavonoids (flavones, flavonols) the ability of compounds to bind Fe2+ ions due to a number of structural features of the compounds was shown. If the compounds possessed Fe2+-chelating properties, the decrease in the area of the chromatographic peaks on the chromatogram was marked. By comparing the resulting chromatogram with that of the untreated sample, it was possible to estimate the value of the effect. Application of this method for the analysis of plant extracts representing a mixture of substances allows determination of the compounds that have the greatest influence on the Fe2+-chelating activity.
Cancer immunotherapy: potential involvement of mediators

The description of a cell-free soluble anti-tumour factor by Carswell et al. in 1975 (Proc Natl Acad Sci USA, 72: 3666–3670) was followed by a long series of experimental and clinical investigations into the role of cell-free mediators in cancer immunotherapy. These investigations included research on the effects of macrophage–derived eicosanoids (cycloxygenase and lipoxygenase derivates of arachidonic acid) and of monokines such as tumour necrosis factor-α, interleukin-1 and granulocyte–monocyte–macrophage–colony stimulating factor) and of lymphocyte products: interleukins and interferons. The investigations yielded information on the effects of various factors on macrophage and T-cell activation in vitro, determination of direct anti-tumour properties on animal and human tumour cells in vitro and on therapeutic effectiveness in tumour-bearing individuals either alone or in combination with other therapeutic factors and their production by tumour cells. During recent years much effort has been dedicated towards the use of the tumour cells transfected with cytokine genes in the preparation of cancer vaccines. Cycloxygenase products (prostaglandins) were usually assumed to inhibit expression of anti-tumour activity by macrophages and an increase in their production in cancer patients was considered as a poor prognostic index. Lipoxygenase (leukotrienes) products were assumed to exhibit antitumour activity and to induce production of IL-1 by macrophages. Interleukins 2, 4, 6, 7, 12 and the interferons were extensively tested for their therapeutic effectiveness in experimental tumour models and in cancer clinical trials. The general conclusion on the use of cell-free mediators for cancer immunotherapy is that much still has to be done in order to assure effective and reproducible therapeutic effectiveness for routine use in the treatment of human neoplasia.
ULTRASTRUCTURE OF MUCOCYSTS AND PELLICLE OF TETRAHYMENA PYRIFORMIS

Tetrahymena pyriformis GL was fixed with glutaraldehyde and/or OsO4 for a study of cytoplasmic ultrastructure. Many small vacuoles 0.05 to 0.5 µ in diameter were found to contain each a dense particle enveloped by a limiting membrane. This membrane is continuous with the membrane of the vacuole. The particles are irregular in shape and size, but similar to the mucocysts in the appearance of the matrix. It is suggested that they are the first morphologically distinguishable stages in the development of mucocysts. In the course of this development, amorphous material becomes crystalline with a longitudinal period of 150 A and a lateral period of 100 A. The mature mucocysts are rather uniform in size and have a spheroidal shape. During discharge, the crystalline pattern disappears and the mucocysts assume a spherical configuration. The inner limiting membrane of a mucocyst seems to disintegrate during the process of discharge while the outer membrane becomes continuous with the outermost pellicular membrane; the inner pellicular membrane is continuous with the cytoplasmic membrane. Rows of few to 15 or more microtubules were found either between the cytoplasmic membrane and the ectoplasmic layer (longitudinal fibrils) or underneath the ectoplasmic layer (transverse fibrils). The outer and inner pellicular membranes are uniformly spaced and connected by "cross-bridges. " Details of these structures are described.
Mechanism of the Association between Na+ Binding and Conformations at the Intracellular Gate in Neurotransmitter:Sodium Symporters*

Background: The intramolecular pathways propagating the impact of Na+ binding in neurotransmitter:sodium symporters (NSSs) are not sufficiently understood. Results: We identified computationally and verified experimentally an interaction network connecting Na+ binding with the intracellular gate. Conclusion: The identified pathways are conserved between bacterial LeuT and eukaryotic hDAT. Significance: We gain a new understanding of the structural basis for the functional role of Na+ binding in NSSs. Neurotransmitter:sodium symporters (NSSs) terminate neurotransmission by Na+-dependent reuptake of released neurotransmitters. Previous studies suggested that Na+-binding reconfigures dynamically coupled structural elements in an allosteric interaction network (AIN) responsible for function-related conformational changes, but the intramolecular pathway of this mechanism has remained uncharted. We describe a new approach for the modeling and analysis of intramolecular dynamics in the bacterial NSS homolog LeuT. From microsecond-scale molecular dynamics simulations and cognate experimental verifications in both LeuT and human dopamine transporter (hDAT), we apply the novel method to identify the composition and the dynamic properties of their conserved AIN. In LeuT, two different perturbations disrupting Na+ binding and transport (i.e. replacing Na+ with Li+ or the Y268A mutation at the intracellular gate) affect the AIN in strikingly similar ways. In contrast, other mutations that affect the intracellular gate (i.e. R5A and D369A) do not significantly impair Na+ cooperativity and transport. Our analysis shows these perturbations to have much lesser effects on the AIN, underscoring the sensitivity of this novel method to the mechanistic nature of the perturbation. Notably, this set of observations holds as well for hDAT, where the aligned Y335A, R60A, and D436A mutations also produce different impacts on Na+ dependence. Thus, the detailed AIN generated from our method is shown to connect Na+ binding with global conformational changes that are critical for the transport mechanism. That the AIN between the Na+ binding sites and the intracellular gate in bacterial LeuT resembles that in eukaryotic hDAT highlights the conservation of allosteric pathways underlying NSS function.
BDNF variant Val66Met interacts with estrous cycle in the control of hippocampal function

Natural fluctuations in circulating estradiol are associated with behavioral changes, including severe disturbances in mood and cognition in some women. Common genetic variation in some of the molecular mediators of estradiol effects on these behaviors, in brain regions such as the hippocampus, may explain individual variation in estradiol effects on behavior. We tested whether the common human variant BDNF Val66Met interacts with estradiol in the control of hippocampal function in cycling female mice homozygous for the wild-type Val or BDNF Met variant. BDNF Met increased anxiety behavior, impaired memory, and increased expression of BDNF and its receptor TrkB in the hippocampal formation. BDNF Met also dramatically altered the fluctuation of spatial memory, hippocampal Akt phosphorylation, and PSD-95 protein expression across the estrous cycle. The variant BDNF Val66Met should therefore be considered as a strong candidate for mediating genetic differences in ovarian steroid-related behavioral changes and disorders.
On the Interplay between Channel Sensing and Estimation in Cognitive Radio Systems

Cognitive radio transmissions in the presence of channel uncertainty are considered. In practical scenarios, cognitive secondary users need to perform both channel sensing in order to identify whether the channel is being occupied by the primary users or not, and also channel estimation in order to learn the channel fading coefficients. Generally, errors occur in both channel sensing and estimation, and this leads to a coupling between the two. More specifically, imperfect sensing affects both the structure and the performance of channel estimation schemes. With this motivation, the interactions between channel sensing and estimation are studied in this paper. In particular, different channel estimation schemes including minimum mean-square error (MMSE), linear MMSE, and mismatched MMSE estimations are analyzed, and their dependence on sensing decisions and their performances are investigated.
Evidence of complex involvement of serotonergic genes with restrictive and binge purge subtypes of anorexia nervosa

Abstract Objectives. There is mixed evidence of association of serotoninergic genes with anorexia nervosa (AN), but substantial evidence for the involvement of serotonergic mechanisms in appetite control. This study was designed to investigate possible associations between the two subtypes of AN (Restricting-RAN, and Binge-purging–BPAN) and polymorphisms within five genes encoding for proteins involved in the serotoninergic system. Methods. In order to carry out this investigation we have conducted a case–control association study on 226 females meeting the criteria for AN, and 678 matched healthy females. Results. Our data show a significant association between polymorphisms with the gene encoding HTR2A with both AN subtypes, an association between polymorphisms within the genes encoding HTR1D and HTR1B with RAN, and an association between polymorphisms within the gene encoding HTR2C with BPAN. No associations were found for any polymorphisms of the serotonin transporter gene. This outcome indicates a substantial and complex inter-relationship between serotoninergic genes and AN. Conclusions. Given these data we hypothesis that the expression or control of expression of several genes of the serotoninergic system, and interactions between these genes, could exert considerable influence over the specific symptomatology of the subtypes of AN.
Population Growth Inflates the Per-Individual Number of Deleterious Mutations and Reduces Their Mean Effect

This study addresses the question of how purifying selection operates during recent rapid population growth such as has been experienced by human populations. This is not a straightforward problem because the human population is not at equilibrium: population genetics predicts that, on the one hand, the efficacy of natural selection increases as population size increases, eliminating ever more weakly deleterious variants; on the other hand, a larger number of deleterious mutations will be introduced into the population and will be more likely to increase in their number of copies as the population grows. To understand how patterns of human genetic variation have been shaped by the interaction of natural selection and population growth, we examined the trajectories of mutations with varying selection coefficients, using computer simulations. We observed that while population growth dramatically increases the number of deleterious segregating sites in the population, it only mildly increases the number carried by each individual. Our simulations also show an increased efficacy of natural selection, reflected in a higher fraction of deleterious mutations eliminated at each generation and a more efficient elimination of the most deleterious ones. As a consequence, while each individual carries a larger number of deleterious alleles than expected in the absence of growth, the average selection coefficient of each segregating allele is less deleterious. Combined, our results suggest that the genetic risk of complex diseases in growing populations might be distributed across a larger number of more weakly deleterious rare variants.
Body weight, body composition, and energy metabolism in lean and obese Zucker rats fed soybean oil or butter.

BACKGROUND Dietary fat composition is thought to affect body weight regulation independent of the amount of fat ingested. OBJECTIVE We analyzed the feeding behavior, body weight gain, body composition, and energy metabolism in lean and obese rats fed a diet in which fat was in the form of either butter or soybean oil. DESIGN Ten lean (Fa/? ) and 10 obese (fa/fa) adult Zucker rats were divided into 4 groups according to a 2 x 2 experimental design. They were fed a normally balanced diet over 11 wk in which 30% of energy was either soybean oil or butter. Food intake, body weight gain, and body composition were measured. Indirect calorimetry was used to study energy metabolism at rest and in relation to feeding and activity. RESULTS Food intake increased similarly in lean and obese rats after butter feeding. Body weight gain increased in obese rats and decreased in lean rats after butter feeding. Body weight gain in obese rats was due mainly to an increase in the weight of lean tissues besides muscle, whereas adiposity and distribution of fat between the various pads did not change. Resting metabolic rates and postprandial lipid oxidation increased in butter-fed obese rats. Lipid oxidation during exercise was not significantly different between obese and lean rats. Fat oxidation increased in butter-fed lean rats during treadmill running at moderate intensity. CONCLUSIONS In obese rats, basal metabolism and postprandial lipid oxidation increased during butter feeding, which appeared to prevent fat accumulation in the long term. In lean rats, butter feeding favored lipid utilization by working muscles, an observation that deserves further investigation in terms of endurance and performance.