Clustering Memes in Social Media

The increasing pervasiveness of social media creates new opportunities to study human social behavior, while challenging our capability to analyze their massive data streams. One of the emerging tasks is to distinguish between different kinds of activities, for example engineered misinformation campaigns versus spontaneous communication. Such detection problems require a formal definition of meme, or unit of information that can spread from person to person through the social network. Once a meme is identified, supervised learning methods can be applied to classify different types of communication. The appropriate granularity of a meme, however, is hardly captured from existing entities such as tags and keywords. Here we present a framework for the novel task of detecting memes by clustering messages from large streams of social data. We evaluate various similarity measures that leverage content, metadata, network features, and their combinations. We also explore the idea of pre-clustering on the basis of existing entities. A systematic evaluation is carried out using a manually curated dataset as ground truth. Our analysis shows that pre-clustering and a combination of heterogeneous features yield the best trade-off between number of clusters and their quality, demonstrating that a simple combination based on pairwise maximization of similarity is as effective as a non-trivial optimization of parameters. Our approach is fully automatic, unsupervised, and scalable for real-time detection of memes in streaming data.Comment: Proceedings of the 2013 IEEE/ACM International Conference on Advances in Social Networks Analysis and Mining (ASONAM'13), 201

Redes neuronales artificiales para simular el efecto del viento sobre el patrón de distribución del agua de un aspersor

A new approach based on Artificial Neural Networks (ANNs) is presented to simulate the effects of wind on the distribution pattern of a single sprinkler under a center pivot or block irrigation system. Field experiments were performed under various wind conditions (speed and direction). An experimental data from different distribution patterns using a Nelson R3000 Rotator® sprinkler have been split into three and used for model training, validation and testing. Parameters affecting the distribution pattern were defined. To find an optimal structure, various networks with different architectures have been trained using an Early Stopping method. The selected structure produced R2= 0.929 and RMSE = 6.69 mL for the test subset, consisting of a Multi-Layer Perceptron (MLP) neural network with a backpropagation training algorithm; two hidden layers (twenty neurons in the first hidden layer and six neurons in the second hidden layer) and a tangent-sigmoid transfer function. This optimal network was implemented in MATLAB® to develop a model termed ISSP (Intelligent Simulator of Sprinkler Pattern). ISSP uses wind speed and direction as input variables and is able to simulate the distorted distribution pattern from a R3000 Rotator® sprinkler with reasonable accuracy (R2> 0.935). Results of model evaluation confirm the accuracy and robustness of ANNs for simulation of a single sprinkler distribution pattern under real field conditions.Se presenta un nuevo modelo basado en la técnica de Redes Neuronales Artificiales (RNA) para simular el efecto del viento sobre la distribución de agua de un aspersor, en un sistema estacionario o en equipos pivote. Se han realizado una serie de ensayos experimentales con diferentes velocidades y direcciones de viento, para el emisor Rotator R3000 de Nelson. El conjunto de datos obtenidos para los diferentes patrones de distribución del agua han sido divididos en tres grupos, y utilizados en las correspondientes fases de entrenamiento, análisis y validación. Se han definido los parámetros que influyen sobre el patrón de distribución de agua. Con el fin de encontrar una estructura de red óptima, varias redes con diferente arquitectura han sido entrenadas usando un método supervisado. Con la estructura óptima se consiguió un R2= 0,929 y RMSE = 6,69 mL para el grupo de ensayos correspondientes a la red Multi-Layer Perceptron (MLP) mediante el algoritmo de aprendizaje supervisado con retroalimentación, dos niveles de capas ocultas (veinte neuronas en el primer nivel y seis neuronas en el segundo) y una función de transferencia tangente hiperbólica. Esta red optimizada fue implementada en MATLAB para desarrollar un modelo llamado ISSP (Simulador Inteligente del Modelo de Distribución). ISSP utiliza la velocidad y dirección de viento como variables de entrada y tiene la capacidad de simular el modelo distorsionado de la distribución de agua de un emisor Rotator R3000 con una buena precisión (R2> 0,935). Los resultados confirman la precisión y robustez de las técnicas de RNA para simular el patrón de distribución del agua de un aspersor en condiciones de campo

Online Popularity and Topical Interests through the Lens of Instagram

Online socio-technical systems can be studied as proxy of the real world to investigate human behavior and social interactions at scale. Here we focus on Instagram, a media-sharing online platform whose popularity has been rising up to gathering hundred millions users. Instagram exhibits a mixture of features including social structure, social tagging and media sharing. The network of social interactions among users models various dynamics including follower/followee relations and users' communication by means of posts/comments. Users can upload and tag media such as photos and pictures, and they can "like" and comment each piece of information on the platform. In this work we investigate three major aspects on our Instagram dataset: (i) the structural characteristics of its network of heterogeneous interactions, to unveil the emergence of self organization and topically-induced community structure; (ii) the dynamics of content production and consumption, to understand how global trends and popular users emerge; (iii) the behavior of users labeling media with tags, to determine how they devote their attention and to explore the variety of their topical interests. Our analysis provides clues to understand human behavior dynamics on socio-technical systems, specifically users and content popularity, the mechanisms of users' interactions in online environments and how collective trends emerge from individuals' topical interests.Comment: 11 pages, 11 figures, Proceedings of ACM Hypertext 201

Investigating the relationship between low serum cholesterol and suicide in attempters with depression

Background & Objective: It has been postulated that depressed individuals with low total cholesterol levels may be more likely to die prematurely from suicide. This study aimed to examine the association between low serum cholesterol and suicide in depressed attempters. Materials & Methods: In this cross-sectional study, 180 suicide attempters, who met the inclusion criteria and were willing to participate in the study, were recruited in 2017. The data was collected using a demographic questionnaire and the Beck Depression Inventory-Second Edition (BDI-II). The blood cholesterol level was measured via an auto-analyzer. Results: The mean age was 26.39±10.75 years. The average cholesterol level in the moderate, severe, and serious depression groups was 151.30±35.23, 145.89±36.32, and 145.15±33.33, respectively. The mean age was higher in the group with a higher depression level, though the difference was not significant (P=0.06). The percentage of suicide attempts in single individuals was significantly higher (P=0.02). The mean cholesterol level in the group with the highest level of depression was the lowest, but the difference was insignificant (r=-.01, P=0.85). Only in females, the level of blood cholesterol showed a nearly significant difference between groups with different severities of depression (P=0.05). Cholesterol had a significant correlation with suicide frequency (P=0.008, r=0.28). Conclusion: Our results revealed no significant association between low serum cholesterol and suicide in attempters with depression; but low total serum cholesterol may be associated with depression and suicide in depressed subjects. Yet, more studies are required for verification of this causality. © 2020, Journal of Advances in Medical and Biomedical Research. All rights reserved

EAIMS: Emergency Analysis Identification and Management System

Social media has great potential as a means to enable civil protection and law enforcement agencies to more effectively tackle disasters and emergencies. However, there is currently a lack of tools that enable civil protection agencies to easily make use of social media. The Emergency Analysis Identification and Management System (EAIMS) is a prototype service that provides real-time detection of emergency events, related information finding and credibility analysis tools for use over social media during emergencies. This system exploits machine learning over data gathered from past emergencies and disasters to build effective models for identifying new events as they occur, tracking developments within those events and analyzing those developments for the purposes of enhancing the decision making processes of emergency response agencies

Sayyadi H. Prenatal Stress+Morphine and Postnatal Re-Exposure to Stress Alter Pentylentetrazol-Induced Epileptic Manifestations in Rats

We studied effects of restraint-induced stress and morphine co-administration within the prenatal period and of re-exposure to stress at the end of infancy on the body mass and pentylenetetrazol-induced epileptic manifestations in rats. Pregnant rats were divided into six groups (control, restraint-stressed, saline, morphine, stress+saline, and stress+morphine). In the stressed groups, pregnant rats were subjected to restraint stressing twice per day for three consecutive days (starting on pregnancy day 15). Rats in saline and morphine groups received saline and morphine subcutaneously at the same days. In the morphine/saline+stressed groups, rats were exposed to stress and received morphine/saline simultaneously. Control rats were left intact. The pups were weighed at postnatal days (PD) 1, 15, and 22. On P22, half of the pups were re-exposed to stress; then, pentylenetetrazol (PTZ)-induced seizures were recorded. The offspring body mass was significantly smaller in stressed, morphine, and stressed+morphine groups compared to the control. The time to onset of the first tonico-clonic seizure was shorter, while the duration and number of tonico-clonic attacks were greater significantly in the stressed+morphine group compared to other groups. Re-exposure to stress decreased the number of clonic seizures. The number of leg-opening and tail rigidity episodes were smaller in female offspring compared to male ones. Co-administration of restraint stress and morphine within the prenatal period reduces the offspring body mass and increases the seizure vulnerability more severely compared to the respective individual effects In addition, prenatal stress exerts stronger effects on the neural development and epileptic behaviors of the offspring than postnatal stress.Ми досліджували на щурах впливи пренатально індукованого іммобілізаційного стресу, який комбінували з уведенням морфіну, а також повторного стресування щурів-нащадків наприкінці «періоду дитинства» на прояви індукованої пентилентетразолом (ПТЗ) епілептиформної активності у цих нащадків. Вагітні самиці щурів були розділені на шість груп (контроль, стресовані іммобілізацією, з уведенням фізіологічного розчину – ФР, з уведенням морфіну, стресовані+ФР та стресовані+морфін). Вагітні самиці стресованої групи були піддані сеансам іммобілізаційного стресування двічі за день протягом трьох послідовних днів (починаючи з 15-го дня вагітності). Щуриці груп ФР та «морфін» отримували відповідні підшкірні ін’єкції протягом тих самих трьох діб. У групах «морфін/ФР+стрес» щури піддавалися комбінації стресування та відповідних ін’єкцій; контрольні щури залишалися інтактними. Народжені щурята зважувались у постнатальні дні ПД, 1, 15 та 22. У ПД 22 половину щурят піддавали повторному стресуванню. Після цього в усіх нащадків реєстрували епілептиформну судомну активність, індуковану введенням ПТЗ. Маса тіла щурят стресованої, «морфінової» груп та групи «стрес+морфін» була вірогідно нижчою, ніж у щурят контрольної групи. Час до проявів першої тоніко-клонічної судоми у тварин групи «стрес+морфін» був вірогідно коротшим, ніж в інших групах. Тривалість та кількість тоніко-клонічних нападів у згаданій вище групі («стрес+морфін») були вірогідно більшими. Повторне постнатальне стресування призводило до зменшення кількості клонічних судом. Отже, комбінація пренатального іммобілізаційного стресу та введення морфіну викликає зменшення маси тіла та підвищення чутливості до судомної активності, і ці ефекти сильніші, ніж впливи вказаних факторів поодинці. Окрім того, пренатальний стрес спричинює сильніші впливи на розвиток нервової системи та прояви епілептиформної активності у нащадків, аніж постнатальний стрес

NF-κB-dependent mechanism of action of c-Myc inhibitor 10058-F4: Highlighting a promising effect of c-Myc inhibition in Leukemia cells, irrespective of p53 status

Due to the frequent contribution in the pathogenesis of different human malignancies, c-Myc is among those transcription factors that are believed to be pharmacologically targeted for cancer therapeutic approaches. In the present study, we examined the anti-leukemic effect of a well-known c-Myc inhibitor 10058-F4 on a panel of hematologic malignant cells harboring either mutant or wild-type p53. Notably, we found that the suppression of c-Myc was coupled with the reduction in the survival of all the tested leukemic cells; however, as far as we are aware, this study suggests for the first time that the cytotoxic effect of 10058-F4 was not significantly affected by the molecular status of p53. Delving into the molecular mechanisms of the inhibitor in the most sensitive cell line revealed that 10058-F4 could induce apoptotic cell death in mutant p53-expressing NB4 cells through the suppression of NF-κB pathway coupled with a significant induction of intracellular reactive oxygen species (ROS). In addition, we found that the anti-leukemic effect of 10058-F4 was overshadowed, at least partially, through the compensatory activation of the PI3K signaling pathway; highlighting a plausible attenuating role of this axis on 10058-F4 cytotoxicity. In conclusion, the results of the present study shed light on the favorable anti-leukemic effect of 10058-F4, especially in combination with PI3K inhibitors in acute promyelocytic leukemia; however, further investigations should be accomplished to determine the efficacy of the inhibitor, either as a single agent or in a combined-modal strategy, in leukemia treatment. © 2020, Iranian Journal of Pharmaceutical Research. All rights reserved

Contribution value of akt, c-myc, cip2a, and pp2a genes expression in leukemogenesis: A bright perspective on the molecular pattern of patients with acute myeloid leukemia (aml)

Background: The heterogeneous nature of acute myeloid leukemia (AML) and the hurdle to find a suitable treatment strategy for this malignancy put this type of leukemia at the top of the list of the priorities for finding a valuable biomarker to improve its treatment and predict the outcome of the patients. Objectives: Given the involvement of the variety of signaling pathways, foremost the PI3K axis in the pathogenesis of human can-cers, we aimed to investigate the expression of the most important downstream targets of this pathway to propose a plausible mechanism underlying AML pathogenesis. Methods: In this case-control study, the blood samples from 30 patients diagnosed with AML were collected and after extracting their RNAs, the expression levels of Akt, c-Myc, CIP2A, and PP2A were evaluated using qRT-PCR analysis. For the control group, we also collected blood samples from 10 healthy volunteers. Afterward, by applying statistical analysis, we determined the probable correlation between the expressions of the aforementioned genes. Results: There was a significant elevation in the expression levels of Akt, c-Myc, and CIP2A coupled with the meaningful reduction in the expression level of PP2A in AML samples. However, we failed to find any significant association between the expression level of the indicated genes and age, sex, and the percentage of the blasts. Conclusions: As the most straightforward interpretation of our results, we propose that probably the association between PI3K and c-Myc which is built through the interaction between CIP2A and PP2A may play a pivotal role in the pathogenies of AML and any component of this axis could serve as a potential new target for more profound treatment strategy. However, further detailed inves-tigations in this field are required to clarify the exact role of this interesting testis-specific pathway in the context of hematological malignancies, in particular AML. © 2020, Author(s)

Immunogenicity of COVID-19 mRNA vaccines in hemodialysis patients: Systematic review and meta-analysis

Background and Aims Vaccine response is a concern in hemodialysis patients. Given that hemodialysis patients were not included in clinical trials, we aimed to synthesize the available evidence on the immunogenicity of coronavirus disease 2019 (COVID-19) mRNA vaccines in hemodialysis patients. Methods We searched Scopus, PubMed, Sciencedirect, and finally google scholar databases for studies on COVID-19 mRNA-vaccines immunogenicity in hemodialysis patients up to December 1, 2021. Eligible articles measured antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike or Receptor-Binding Domain Antibody (S/RBD) postimmunization with COVID-19 mRNA vaccines. The immunogenicity of the vaccine was evaluated using seroconversion rates measured between 21 and 30 days after the first immunization and between 14 and 36 days post the second dose. We included studies including participants without a history of COVID-19 before vaccination. Healthy controls or health-care workers served as the control groups. After selecting eligible articles, the data were finally extracted from included articles. We used a random effects model to estimate the pooled seroconversion rate after COVID-19 mRNA vaccine administration. We assessed the heterogeneity between studies with the I-2 statistical index. Result We selected 39 eligible citations comprising 806 cases and 336 controls for the first dose and 6314 cases and 927 controls for the second dose for statistical analysis. After the first dose of mRNA vaccines, the seroconversion rate was 36 (95 confidence interval CI: 0.24-0.47) and 68% (95% CI: 0.45-0.91) in hemodialysis patients and the control group, respectively. While seroconversion rate after the second dose of mRNA vaccines was 86% (95% CI: 0.81-0.91) and 100% (95% CI: 1.00-1.00) in hemodialysis patients and the control group, respectively. Conclusion Although the immune response of hemodialysis patients to the second dose of the SARS-CoV-2 mRNA vaccine is very promising, the seroconversion rate of dialysis patients is lower than healthy controls. Periodically assessment of antibody levels of hemodialysis patients at short intervals is recommended