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Electronic devices (e.g., cellphones) are a means of technology advancement, but research suggests that frequent use of them in the classroom impairs attention and learning (Lee et al., 2017; Mendoza et al., 2018; Lee et al., 2020). The present study (N = 393) establishes a pre-existing regression model examining the significance of mindfulness (MND) to emotional regulation and cognitive performance among college students. Results suggest that MND's effect on obsessiveness across all four conditions were seen: Group A, cellphone allowed, Group B, cellphone on silent mode, Group C, control group, and Group D, no cellphones. The findings also indicate that highly nomophobic participants in Group B showed better test performance. We expect that students' excessive use of cellphones may have a negative impact on MND, especially when there are no cellphone restrictions. Keywords: Cellular telephones, mindfulness [MND], nomophobia, obsessiveness [OBS], structural equation modeling (SEM), testing., Introduction Cellphones have been used for at least 10-15 years. College-aged students are one of the oldest groups using them in circumstances that require attention (Lee et al., 2017; Lee [...]

Students' cellphone use has been related to poorer learning, possibly due to greater distraction. This study investigated whether cellphone-related anxiety, addiction, and disconnection were related to distraction and learning as well as how practical educational policies could minimize negative effects. Participants (N = 218) watched a video lecture and were divided into two groups: cellphone-allowed for academic use (Use-Cellphone Group) and no cellphone instruction (No-Instruction Group). During the lecture, participants received several anonymous text messages and overt distracted was measured. Learning was assessed via a test following the video. Our findings showed that participants in the Use-Cellphone Group experienced a greater degree of distraction and worse test performance than those in the No-Instruction Group. Only cellphone addiction and distractedness played key roles in impacting the effects of condition on test performance. Thus, allowing cellphones in class may exacerbate existing cellphone addiction behaviors and impair learning.

Copyright of Boletín Médico del Hospital Infantil de México is the property of Publicidad Permanyer SLU and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Pineapple is an economically important tropical fruit crop, but the lack of adequate planting material limits its productivity. A range of micropropagation protocols has been developed over the years to address this shortfall. Still, the final stage of micropropagation, i.e. acclimatisation, remains a challenge as pineapple plantlets grow very slowly. Several studies have been conducted focusing on this phase and attempting to improve plantlet growth and establishment, which requires tools for the non-destructive evaluation of growth during acclimatisation. This report describes the use of semi-automated and automated image analysis to quantify canopy growth of pineapple plantlets, during five months of acclimatisation. The canopy area progressively increased during acclimatisation, particularly after 90 days. Regression analyses were performed to determine the relationships between the automated image analysis and morphological indicators of growth. The mathematical relationships between estimations of the canopy area and the fresh and dry weights of intact plantlets, middle-aged leaves (D leaves) and roots showed determination coefficients (R2) between 0.84 and 0.92. We propose an appropriate tool for the simple, objective and non-destructive evaluation of pineapple plantlets growth, which can be generally applied for plant phenotyping, to reduce costs and develop streamlined pipelines for the assessment of plant growth.

Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis, poses a great threat to human health. With the emergence of drug resistant Mtb strains, new therapeutics are desperately needed. As iron is critical to the growth and survival of Mtb, mechanisms through which Mtb acquires host iron represent attractive therapeutic targets. Mtb scavenges host iron via Mtb siderophore-dependent and heme iron uptake pathways. While multiple studies describe the import of heme and ferric-siderophores and the export of apo-siderophores across the inner membrane, little is known about their transport across the periplasm and cell-wall environment. Mtb FecB and FecB2 are predicted periplasmic binding proteins implicated in host iron acquisition; however, their precise roles are not well understood. This study sought to differentiate the roles FecB and FecB2 play in Mtb iron acquisition. The crystallographic structures of Mtb FecB and FecB2 were determined to 2.0 Å and 2.2 Å resolution, respectively, and show distinct ligand binding pockets. In vitro ligand binding experiments for FecB and FecB2 were performed with heme and bacterial siderophores from Mtb and other species, revealing that both FecB and FecB2 bind heme, while only FecB binds the Mtb sideophore ferric-carboxymycobactin (Fe-cMB). Subsequent structure-guided mutagenesis of FecB identified a single glutamate residue—Glu339—that significantly contributes to Fe-cMB binding. A role for FecB in the Mtb siderophore-mediated iron acquisition pathway was corroborated by Mycobacterium smegmatis and Mtb pull-down assays, which revealed interactions between FecB and members of the mycobacterial siderophore export and import machinery. Similarly, pull-down assays with FecB2 confirms its role in heme uptake revealing interactions with a potential inner membrane heme importer. Due to ligand preference and protein partners, our data suggest that Mtb FecB plays a role in siderophore-dependent iron and heme acquisition pathways; in addition, we confirm that Mtb FecB2 is involved in heme uptake. Author summary: Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis, has long presented a threat to human health across the world and remains one of the leading infectious causes of death. Understanding how Mtb can survive and flourish in human hosts allows us to identify potential avenues for therapeutics. As iron is essential to Mtb survival, the mechanisms by which Mtb acquires iron from the host is a particularly attractive avenue. Here, we present evidence that two Mtb predicted periplasmic binding proteins, FecB and FecB2, are involved in iron uptake mechanisms. With ligand-binding experiments, we show that FecB2 specifically binds heme, while FecB can bind heme and the Mtb siderophore carboxymycobactin (cMB) in both its apo and iron bound forms. We also identify a FecB residue involved in ferric-cMB recognition using structure function analysis. Lastly, using co-immunoprecipitation, we identify FecB protein interaction partners that place FecB in the siderophore-dependent iron acquisition pathway and we confirm that Mtb FecB2 is involved in heme uptake. These experiments provide new and important information about a poorly understood, but essential Mtb survival mechanism, which ultimately may allow for novel anti-Mtb therapeutics. [ABSTRACT FROM AUTHOR]

Copyright of Policy Studies Journal is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Electrónica de Psicología Iztacala is the property of Facultad de Estudios Superiores Iztacala and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Central nervous system (CNS) tuberculosis is the most lethal and devastating form among the diseases caused by Mycobacterium tuberculosis. The mechanisms by which M. tuberculosis bacilli enter the CNS are still unclear. However, the BBB and the BCSFB have been proposed as possible routes of access into the brain. We previously reported that certain strains of M. tuberculosis possess an enhanced ability to cause secondary CNS infection in a mouse model of progressive pulmonary tuberculosis. Here, we evaluated the morphostructural and molecular integrity of CNS barriers. For this purpose, we analyzed through transmission electron microscopy the ultrastructure of brain parenchymal microvessels and choroid plexus epithelium from animals infected with two mycobacterial strains. Additionally, we determined the expression of junctional proteins and cytokines by immunological techniques. The results showed that the presence of M. tuberculosis induced disruption of the BCSFB but no disruption of the BBB, and that the severity of such damage was related to the strain used, suggesting that variations in the ability to cause CNS disease among distinct strains of bacteria may also be linked to their capacity to cause direct or indirect disruption of these barriers. Understanding the pathophysiological mechanisms involved in CNS tuberculosis may facilitate the establishment of new biomarkers and therapeutic targets. [ABSTRACT FROM AUTHOR]

BACKGROUND: Metastasis to the oral cavity is infrequent, representing 1 to 3% of head and neck cases. The types of cancer that commonly cause metastasis to the mouth are lung, kidney, and prostate for men, and breast, kidney, and colon for women. The clinical presentation depends on the affected site and varies from an evident tumor to a slight swallow mimicking a reactive lesion, accompanied by pain and paresthesia. CLINICAL CASE: A 59-year-old woman evaluated in the Pathology and Oral Medicine Clinic of the Autonomous Metropolitan University of the City, diagnosticated with oral metastasis from renal carcinoma. CONCLUSION: Clinical findings lead to an accurate diagnosis; it is important to offer the appropriate treatment, by the specialist in Pathology and Oral Medicine, as part of the multidisciplinary team, to ensure a better quality of life in this type of patient. [ABSTRACT FROM AUTHOR]

Copyright of Revista CIENCIA UNEMI is the property of Universidad Estatal de Milagro (UNEMI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Mutations on KIT and downstream genes of MAPK pathway that overstimulate cellular proliferation have been associated with primary oral and sinonasal melanomas (POSNM), but there is limited information that allows the use of personalized therapy. Thus, the aim of the present study was to determine a possible association between the C-KIT immunohistochemical expression with the presence of somatic driver mutations in NRAS, BRAF, KIT, MITF and PTEN on POSNM.Methods: A retrospective study included 62 tumour samples of an oncological reference centre in Mexico City (17-year period). Immunohistochemistry stain of C-KIT was carried out. Genomic DNA was obtained and used to assess hotspot mutations of KIT, NRAS, BRAF, MITF and PTEN through qPCR. Chi-square, Fisher's exact and the Mann-Whitney U tests were applied when necessary. The significance was set at P < 0.05.Results: Sixty-two cases were included, 74% were positive for C-KIT immunoexpression, all exhibited moderate/strong intensity. Ten (16.1%) samples harboured at least one mutation, 6.4% and 6.6% for NRASQ61R and BRAFV600E , respectively, followed by KITK624E (3.2%). No KITL576P , MITF or PTEN mutations were identified. No significant correlation was observed between mutations and immunostaining (rs = -0.057, P = 0.765).Conclusions: Regardless of the high immunoexpression of C-KIT, there was no association with the MAPK mutations among POSNM samples. Thus, C-KIT immunohistochemistry is not a reliable tool to detect POSNM candidates for biological therapy. [ABSTRACT FROM AUTHOR]

Summary: Students' cellphone use has been related to poorer learning, possibly due to greater distraction. This study investigated whether cellphone‐related anxiety, addiction, and disconnection were related to distraction and learning as well as how practical educational policies could minimize negative effects. Participants (N = 218) watched a video lecture and were divided into two groups: cellphone‐allowed for academic use (Use‐Cellphone Group) and no cellphone instruction (No‐Instruction Group). During the lecture, participants received several anonymous text messages and overt distracted was measured. Learning was assessed via a test following the video. Our findings showed that participants in the Use‐Cellphone Group experienced a greater degree of distraction and worse test performance than those in the No‐Instruction Group. Only cellphone addiction and distractedness played key roles in impacting the effects of condition on test performance. Thus, allowing cellphones in class may exacerbate existing cellphone addiction behaviors and impair learning. [ABSTRACT FROM AUTHOR]

Thanks to evolving cellular telecommunication networks, providers can deploy a wide range of services. Soon, 5G mobile networks will be available to handle all types of services and applications for vast numbers of users through their mobile equipment. To effectively manage new 5G systems, end-to-end (E2E) performance analysis and optimization will be key features. However, estimating the end-user experience is not an easy task for network operators. The amount of end-user performance information operators can measure from the network is limited, complicating this approach. Here we explore the calculation of service metrics [known as key quality indicators (KQIs)] from classic low-layer measurements and parameters. We propose a complete machine-learning (ML) modeling framework. This system’s low-layer metrics can be applied to measure service-layer performance. To assess the approach, we implemented and evaluated the proposed system on a real cellular network testbed. [ABSTRACT FROM AUTHOR]

Copyright of Innovar: Revista de Ciencias Administrativas y Sociales is the property of Universidad Nacional de Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose The BRAF V600E mutation has been described in melanomas occurring in the Caucasian, European, and Asian populations. However, in the Mexican population, the status and clinical significance of BRAF mutation has not been researched on a large scale. Methods Consecutive BRAF-tested Mexican patients with metastatic melanoma (n=127) were analyzed for mutations in exon 15 of the BRAF gene in genomic DNA by real-time polymerase chain reaction technology for amplification and detection. The results were correlated with the clinical-pathologic features and the prognosis of the patients. Results The frequency of somatic mutation V600E within the BRAF gene was 54.6% (43 of 127 patients). Nodular melanoma was the most prevalent subtype in our population, with BRAF mutations in 37.2% (16 of 55 patients). In contrast, superficial spread had a frequency of 18.6% BRAF mutation (eight of 24). Other clinicopathologic features were assessed to correlate with the mutation status. Conclusion This study searched for the most prevalent BRAF V600E mutation type in melanoma in a heterogeneous population from Mexico. Nodular melanoma was found to be the most prevalent in metastatic presentation and the presence of BRAF V600E mutation, perhaps related to the mixed ancestry; in the north, ancestry is predominantly European and in the south, it is predominantly Asian. The outcomes of the mutation correlations were similar to those found in other populations. [ABSTRACT FROM AUTHOR]

Purpose: The BRAF V600E mutation has been described in melanomas occurring in the Caucasian, European, and Asian populations. However, in the Mexican population, the status and clinical significance of BRAF mutation has not been researched on a large scale. Methods: Consecutive BRAF -tested Mexican patients with metastatic melanoma (n = 127) were analyzed for mutations in exon 15 of the BRAF gene in genomic DNA by real-time polymerase chain reaction technology for amplification and detection. The results were correlated with the clinical-pathologic features and the prognosis of the patients. Results: The frequency of somatic mutation V600E within the BRAF gene was 54.6% (43 of 127 patients). Nodular melanoma was the most prevalent subtype in our population, with BRAF mutations in 37.2% (16 of 55 patients). In contrast, superficial spread had a frequency of 18.6% BRAF mutation (eight of 24). Other clinicopathologic features were assessed to correlate with the mutation status. Conclusion: This study searched for the most prevalent BRAF V600E mutation type in melanoma in a heterogeneous population from Mexico. Nodular melanoma was found to be the most prevalent in metastatic presentation and the presence of BRAF V600E mutation, perhaps related to the mixed ancestry; in the north, ancestry is predominantly European and in the south, it is predominantly Asian. The outcomes of the mutation correlations were similar to those found in other populations. [ABSTRACT FROM AUTHOR]

Cell phones are becoming an inevitable part of the classroom, but extant research suggests that using cell phones in the classroom impairs academic performance. The present study examined the impact of different cell phone policies on learning and emotion-regulation style. Participants were randomly assigned to one of four experimental conditions: cell phone usage allowed, cell phone possession allowed but without usage, cell phones removed, and a no-instruction control group. All participants watched a 20-minute lecture and were sent text messages to mimic classroom distractions. Afterward, participants took a multiple-choice test and filled out questionnaires assessing their level of obsessiveness, nomophobia, and mindfulness. Participants who had their cell phone taken away performed best on the test with no other differences. None of the emotional-regulation measures moderated the results. These findings provide important insight as to how cell phone policies can optimize learning in the classroom.Copyright © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The mobile communication networks sector has experienced a great evolution during the last few years. The emergence of new services as well as the growth in the number of subscribers have motivated the search for new ways to optimize mobile networks. In this way, the objective pursued by optimization techniques has been evolving, shifting from the traditional optimization of radio parameters to the improvement of the quality perceived by users, known as quality of experience (QoE). In mobile networks, the radio link control (RLC) layer provides a reliable link between both ends of the communication and has a great impact on the QoE. In this paper, the optimization of the QoE for users based on the adjustment of the RLC layer is proposed. For this purpose, two typical services demanded by the users of mobile networks have been selected: the real-time video streaming service and file transfer service. For a broader view of the behavior of the QoE in relation to RLC, optimization tests have been carried out in scenarios with different system bandwidths. In this way, the relationship between the QoE and the optimal configuration of RLC in different network load situations has been analyzed. A proof of concept has been carried out to show the capability of this optimization. To that end, both a cellular network simulator and a live cellular network devised for research purposes have been used. [ABSTRACT FROM AUTHOR]

The world is currently undergoing a new industrial revolution characterized by the digitization and automation of industry through the use of Information and Communication Technologies (ICTs). The construction sector is one of the largest sectors of the industry. Most of the tasks associated with this sector are carried out at worksites that are defined by their dynamism, decentralization, temporality, and the intervention of a large number of workers, subcontractors, machinery, equipment, and materials. These characteristics make this sector a great challenge for the implementation of ICTs. In this paper, the benefits of the use of the Fifth-Generation (5G) of mobile networks in the construction industry are presented. To that end, first, the digitization and automation needs of the sector are jointly analyzed, establishing different use cases and identifying the requirements of each one. Second, the main characteristics of 5G that address these use cases are identified. Third, a global framework for the application of 5G technology to the construction industry is proposed. Finally, an overview of some directions for future work are provided. [ABSTRACT FROM AUTHOR]

Electronic devices (e.g., cellphones) are a means of technology advancement, but research suggests that frequent use of them in the classroom impairs attention and learning (Lee et al., 2017; Mendoza et al., 2018; Lee et al., 2020). The present study (N = 393) establishes a pre-existing regression model examining the significance of mindfulness (MND) to emotional regulation and cognitive performance among college students. Results suggest that MND’s effect on obsessiveness across all four conditions were seen: Group A, cellphone allowed, Group B, cellphone on silent mode, Group C, control group, and Group D, no cellphones. The findings also indicate that highly nomophobic participants in Group B showed better test performance. We expect that students’ excessive use of cellphones may have a negative impact on MND, especially when there are no cellphone restrictions. [ABSTRACT FROM AUTHOR]

Study Objective: To determine the efficacy of continuous intravenous infusion of prostacyclin (epoprostenol) in primary pulmonary hypertension.Design: Randomized trial with 8-week treatment periods and nonrandomized treatment for up to 18 months.Setting: Four referral centers.Patients: Sequential sample of 24 patients with primary pulmonary hypertension. Nineteen patients completed the study. Four patients died and one left the study because of adverse effects (pulmonary edema).Interventions: Continuous intravenous prostacyclin administered by portable infusion pump at doses determined by acute responses during baseline catheterization in ten patients. Nine patients were treated with anticoagulants, oral vasodilators, and diuretics.Measurements and Main Results: Starting with a baseline value for total pulmonary resistance of 21.6 units, there was a decrease of 7.9 units (95% CI, -13.1 to -2.2; P = 0.022) in the prostacyclin-treated group after 8 weeks; there was virtually no change in the conventional therapy group (from 20.6 to 20.4 units, not significant). Six of ten prostacyclin-treated patients who completed the 8-week study period had reductions in mean pulmonary artery pressure of greater than 10 mm Hg, whereas only one of nine in the conventional treatment group had a similar response (P = 0.057). Nine patients receiving prostacyclin for up to 18 months have persistent hemodynamic effects, although dose requirements have increased with time. Complications have been attributable to the drug delivery system.Conclusions: Prostacyclin produces substantial and sustained hemodynamic and symptomatic responses in severe primary pulmonary hypertension and may be useful in the management of some patients with this disease. [ABSTRACT FROM AUTHOR]

The arrival of the fifth generation (5G) standard has further accelerated the need for operators to improve the network capacity. With this purpose, mobile network topologies with smaller cells are currently being deployed to increase the frequency reuse. In this way, the number of nodes that collect performance data is being further risen, so the number of metrics to be managed and analyzed is being highly increased. Therefore, it is fundamental to have tools that automatically inform the network operator of the relevant information within the vast amount of metrics collected. The continuous monitoring of the performance indicators and the automatic detection of anomalies is especially important for network operators to prevent the network degradation and user complaints. Therefore, this paper proposes a methodology to detect and track anomalies in the mobile networks performance indicators online, i.e., in real time. The feasibility of this system was evaluated with several performance metrics and a real LTE Advanced dataset. In addition, it was also compared with the performances of other state-of-the-art anomaly detection systems. [ABSTRACT FROM AUTHOR]

The constant evolution in mobile communications networks have led operators to seek new techniques to optimize their mobile networks with the objective of satisfying the expectations of the users. In this way, traditional optimization techniques based on improving radio indicators, have given way to new techniques based on improving the quality of experience (QoE) perceived by users. This paper is focused on analyzing the impact of the adjustment of radio link control (RLC) layer configuration parameters on the QoE perceived by the users of two different types of services. Firstly, an evaluation of the QoE experienced by the user of a real-time video streaming service with respect to the transmission buffer size of the RLC layer in unacknowledged mode (UM) has been carried out. Secondly, the QoE perceived by the user of a file transfer service in relation to the variation of the configuration parameters of the RLC layer in acknowledged mode (AM) has been evaluated. The study, which has been carried out in a simulated cellular environment, has been performed for different system bandwidth values, thus proving the relationship between the QoE perceived by the users, the optimal RLC configuration parameters values and the available bandwidth. [ABSTRACT FROM AUTHOR]

Introduction: Central nervous system (CNS) tuberculosis (TB) is the most severe form of TB due to its high mortality and functional sequelae. There are several differential diagnoses for TB; and, it can also cause secondary conditions, such as vasculitis. Methodology: 155 biopsies, corresponding to 155 different patients out of 5,386 registered biopsies from 2008-2013, met the criteria of unknown etiology vasculitis and evidence of cerebral vascular disease. These were analyzed to assess the presence of central nervous system TB. The selected cases were assessed with Suzaan Marais (SM) criteria for clinical tuberculosis. After that, Ziehl-Neelsen (ZN) staining and polymerase chain reaction (PCR) were performed to amplify a fragment of the insertion sequence IS6110 of M. tuberculosis. 21 patients met the criteria for definitive tuberculosis by ZN staining and PCR, and 2 met the criteria for possible tuberculosis. Tumor necrosis factor (TNF)- α, TNF-R1, and TNF-R2 were determined by immunohistochemistry in histological sections from formalin-fixed paraffin-embedded (FF-PE) tissues in the 23 selected patients. Results: Granulomatous TB was present in almost half of the cases. TNF-R1 and TNF-R2 were expressed mainly in blood vessels, histiocytes, and macrophages. TNF-R2 expression was higher than the other markers, which suggests an anti-inflammatory response against M. tuberculosis Conclusions: The histopathological presentation of TB is not always limited to granulomas, abscesses, or meningitis; there are also clinical presentations characterized only with chronic inflammation of nervous and vascular tissue. [ABSTRACT FROM AUTHOR]