bluuebunny/crossref_metadata_2025 huggingface dataset:
Risk factors for mortality among Tanzanian infants and children
Authors: Kisenge Rodrick R. , Rees Chris A. , Lauer Jacqueline M. , Liu Enju , Fawzi Wafaie W. , Manji Karim P. , Duggan Christopher P.
Published: June 2020

Background

During the era of the Millennium Development Goals, under 5 mortality rates decreased significantly worldwide; however, reductions were not equally distributed. Children in sub-Saharan Africa still account for more than 50% of the world’s annual childhood deaths among children under 5 years of age. Understanding upstream risk factors for mortality among children may reduce the large burden of childhood mortality in sub-Saharan Africa. Our objective was to identify risk factors for mortality among infants and children in Tanzania.

Methods

We conducted a secondary analysis of data pooled from two randomized-controlled micronutrient supplementation trials. A total of 4787 infants were enrolled in the two trials (n = 2387 HIV-exposed and n = 2400 HIV-unexposed). Predictors of mortality were assessed using unadjusted and adjusted hazard ratios (aHRs).

Results

There were 307 total deaths, 262 (11%) among children who were HIV-exposed and 45 (2%) among children who were HIV-unexposed (P < 0.001). The most common cause of death was respiratory diseases (n = 109, 35.5%). Causes of death did not significantly differ between HIV-exposed and HIV-unexposed children. In adjusted regression analyses, children with birth weight <2500 g (aHR 1.75, 95% CI 1.21–2.54), Apgar score of ≤7 at 5 min (aHR 2.16, 95% CI 1.29–3.62), or who were HIV-exposed but not infected (aHR 3.35, 95% CI 2.12–5.28) or HIV-infected (aHR 27.56, 95% CI 17.43–43.58) had greater risk of mortality.

Conclusions

Infection with HIV, low birthweight, or low Apgar scores were associated with higher mortality risk. Early identification and modification of determinants of mortality among infants and children may be the first step to reducing such deaths.
Seismic inversion by Newtonian machine learning
Authors: Chen Yuqing , Schuster Gerard T.
Published: June 2020

We present a wave-equation inversion method that inverts skeletonized seismic data for the subsurface velocity model. The skeletonized representation of the seismic traces consists of the low-rank latent-space variables predicted by a well-trained autoencoder neural network. The input to the autoencoder consists of seismic traces, and the implicit function theorem is used to determine the Fréchet derivative, i.e., the perturbation of the skeletonized data with respect to the velocity perturbation. The gradient is computed by migrating the shifted observed traces weighted by the skeletonized data residual, and the final velocity model is the one that best predicts the observed latent-space parameters. We denote this as inversion by Newtonian machine learning (NML) because it inverts for the model parameters by combining the forward and backward modeling of Newtonian wave propagation with the dimensional reduction capability of machine learning. Empirical results suggest that inversion by NML can sometimes mitigate the cycle-skipping problem of conventional full-waveform inversion (FWI). Numerical tests with synthetic and field data demonstrate the success of NML inversion in recovering a low-wavenumber approximation to the subsurface velocity model. The advantage of this method over other skeletonized data methods is that no manual picking of important features is required because the skeletal data are automatically selected by the autoencoder. The disadvantage is that the inverted velocity model has less resolution compared with the FWI result, but it can serve as a good initial model for FWI. Our most significant contribution is that we provide a general framework for using wave-equation inversion to invert skeletal data generated by any type of neural network. In other words, we have combined the deterministic modeling of Newtonian physics and the pattern matching capabilities of machine learning to invert seismic data by NML.
Pathogenic Germline Mutations in DNA Repair Genes in Combination With Cancer Treatment Exposures and Risk of Subsequent Neoplasms Among Long-Term Survivors of Childhood Cancer
Authors: Qin Na , Wang Zhaoming , Liu Qi , Song Nan , Wilson Carmen L. , Ehrhardt Matthew J. , Shelton Kyla , Easton John , Mulder Heather , Kennetz Dennis , Edmonson Michael N. , Rusch Michael C. , Downing James R. , Hudson Melissa M. , Nichols Kim E. , Zhang Jinghui , Robison Leslie L. , Yasui Yutaka
Published: June 2020

PURPOSE

To investigate cancer treatment plus pathogenic germline mutations (PGMs) in DNA repair genes (DRGs) for identification of childhood cancer survivors at increased risk of subsequent neoplasms (SNs).

METHODS

Whole-genome sequencing was performed on blood-derived DNA from survivors in the St Jude Lifetime Cohort. PGMs were evaluated in 127 genes from 6 major DNA repair pathways. Cumulative doses of chemotherapy and body region–specific radiotherapy (RT) were abstracted from medical records. Relative rates (RRs) and 95% CIs of SNs by mutation status were estimated using multivariable piecewise exponential models.

RESULTS

Of 4,402 survivors, 495 (11.2%) developed 1,269 SNs. We identified 538 PGMs in 98 DRGs ( POLG, MUTYH, ERCC2, and BRCA2, among others) in 508 (11.5%) survivors. Mutations in homologous recombination (HR) genes were significantly associated with an increased rate of subsequent female breast cancer (RR, 3.7; 95% CI, 1.8 to 7.7), especially among survivors with chest RT ≥ 20 Gy (RR, 4.4; 95% CI, 1.6 to 12.4), or with a cumulative dose of anthracyclines in the second or third tertile (RR, 4.4; 95% CI, 1.7 to 11.4). Mutations in HR genes were also associated with an increased rate of subsequent sarcoma among those who received alkylating agent doses in the third tertile (RR, 14.9; 95% CI, 4.0 to 38.0). Mutations in nucleotide excision repair genes were associated with subsequent thyroid cancer for those treated with neck RT ≥ 30 Gy (RR, 12.9; 95% CI, 1.6 to 46.6) with marginal statistical significance.

CONCLUSION

Our study provides novel insights regarding the contribution of genetics, in combination with known treatment-related risks, for the development of SNs. These findings have the potential to facilitate identification of high-risk survivors who may benefit from genetic counseling and/or testing of DRGs, which may further inform personalized cancer surveillance and prevention strategies.
De-Escalation After DE-ESCALATE and RTOG 1016: A Head and Neck Cancer InterGroup Framework for Future De-Escalation Studies
Authors: Mehanna Hisham , Rischin Danny , Wong Stuart J. , Gregoire Vincent , Ferris Robert , Waldron John , Le Quynh-Thu , Forster Martin , Gillison Maura , Laskar Sarbani , Tahara Makoto , Psyrri Amanda , Vermorken Jan , Porceddu Sandro
Published: June 2020

Human papillomavirus (HPV)-positive oropharyngeal cancer (OPC) is increasing rapidly. The younger age, significantly improved prognosis, and relative morbidity of the standard-of-care cisplatin and radiotherapy in this population have led to the popularization of the concept of treatment de-escalation. The recent results of the first 3 randomized de-escalation trials, however, have shown a clear detriment in survival when cisplatin is omitted or substituted. In view of these results, the Head and Neck Cancer International Group identified the need to issue guidance regarding future de-escalation studies for patients with HPV-positive head and neck cancer to avoid the possibility of patients being harmed. We review the current state of the literature regarding HPV de-escalation trials and present a framework and guidance on future and existing clinical trials for treatment de-escalation of HPV-positive OPC. De-escalation paradigms of HPV-positive OPC should be evaluated in phase II studies, and results should be awaited before proceeding to phase III studies. Implementation into clinical practice before high-level evidence is available should not be undertaken in this context. Finally, harm-minimization techniques should also be evaluated as an alternative to de-escalation of treatment in these patient groups.
Mutual extinction and transparency of multiple incident light waves
Authors: Lagendijk Ad , Mosk Allard P. , Vos Willem L.
Published: June 2020

When a wave is incident on a complex scattering medium, the transmitted intensity differs from the incident one due to extinction. In the absence of absorption, the extinguished power is equal to the total scattered power, a well-known conservation law termed the optical theorem. Here, we extend the case of a single incident wave to the situation of scattering and extinction by multiple incoming waves. The emerging generalized optical theorem has the exciting consequence that multiple incident waves show mutual extinction and mutual transparency, phenomena that do not exist in common forward scattering or self-extinction. Based on both exact calculations of realistic three-dimensional (3D) samples containing many (up to 104) scatterers and on approximate Fraunhofer diffraction theory we make the striking observation that the total extinction of two incident waves is greatly enhanced, called mutual extinction, or greatly reduced, mutual transparency, by up to 100% of the usual single-beam extinction. In view of the surprisingly strong mutual extinction and transparency, we propose new experiments to observe mutual extinction and transparency, namely in two-beam experiments with either elastic and absorbing scatterers, in optical wavefront shaping, in dynamic light scattering, and we discuss possible applications.
Real-Time Video Imaging of Mechanical Motions of a Single Molecular Shuttle with Sub-Millisecond Sub-Angstrom Precision
Authors: Shimizu Toshiki , Lungerich Dominik , Stuckner Joshua , Murayama Mitsuhiro , Harano Koji , Nakamura Eiichi
Published: June 2020

Miniaturized machines have open up a new dimension of chemistry, studied usually as an average over numerous molecules or for a single molecule bound on a robust substrate. Mechanical motions at a single molecule level, however, are under quantum control, strongly coupled with fluctuations of its environment — a system rarely addressed because an efficient way of observing the nanomechanical motions in real time is lacking. Here, we report sub-millisecond sub-Å precision in situ video imaging of a single fullerene molecule shuttling, rotating, and interacting with a vibrating carbon nanotube at 0.625 milliseconds(ms)/frame or 1600 fps, using an electron microscope, a fast camera, and a denoising algorithm. We have achieved in situ observation of the mechanical motions of a molecule coupled with vibration of a carbon nanotube with standard error as small as 0.9 millisecond in time and 0.01 nm in space. We have revealed rich molecular dynamics, where motions are non-linear, stochastic and often non-repeatable, and a work and energy relationship at a molecular level previously undetected by time-averaged measurements or microscopy. The molecular video recording at a 1600-fps rate exceeds by 100 times the previous records of continuous recording of molecular motions.
How to build phylogenetic species trees with OMA
Authors: Dylus David , Nevers Yannis , Altenhoff Adrian M. , Gürtler Antoine , Dessimoz Christophe , Glover Natasha M.
Published: June 2020

Knowledge of species phylogeny is critical to many fields of biology. In an era of genome data availability, the most common way to make a phylogenetic species tree is by using multiple protein-coding genes, conserved in multiple species. This methodology is composed of several steps: orthology inference, multiple sequence alignment and inference of the phylogeny with dedicated tools. This can be a difficult task, and orthology inference, in particular, is usually computationally intensive and error prone if done ad hoc. This tutorial provides protocols to make use of OMA Orthologous Groups, a set of genes all orthologous to each other, to infer a phylogenetic species tree. It is designed to be user-friendly and computationally inexpensive, by providing two options: (1) Using only precomputed groups with species available on the OMA Browser, or (2) Computing orthologs using OMA Standalone for additional species, with the option of using precomputed orthology relations for those present in OMA. A protocol for downstream analyses is provided as well, including creating a supermatrix, tree inference, and visualization. All protocols use publicly available software, and we provide scripts and code snippets to facilitate data handling. The protocols are accompanied with practical examples.
Musealizar el pasado y el presente de la violencia. Un estudio de las percepciones de los visitantes del Museo Casa de la Memoria de Medellín
Authors: Lavielle Julie
Published: June 2020

Este artículo tiene como propósito entender cómo la población percibe los relatos museológicos sobre el conflicto armado colombiano en un contexto en el que el conflicto continúa su vigencia. Esta problemática se aborda a partir de los resultados de un estudio de campo realizado a los visitantes del Museo Casa de la Memoria de Medellín. La metodología es cualitativa y cuantitativa, e incluye cuestionarios, observaciones de visitas y entrevistas con el público. El artículo muestra que la relación de los visitantes con el relato del museo está orientada por varios factores: la relación personal con el conflicto armado, las opiniones políticas y las referencias culturales presentes en la sociedad colombiana, así como, también, por los roles sucesivos que asumen durante su visita. Finalmente, en el artículo se pone en evidencia la relación ambigua de los visitantes con la violencia: por un lado la condenan, pero por otro, justifican o aceptan su uso para perseguir objetivos que estiman justos.
A Foundation for Cue-Triggered Behavior
Authors: Pennesi Daniele
Published: June 2020

Exposure to environmental cues triggers sudden preference reversals in several choice contexts, including consumption and intertemporal, social, and risky choices. This paper introduces a dual-self model of cue-triggered behavior that (1) is based on a general mechanism that makes it applicable to many choice contexts, (2) allows a sharp comparative analysis of the responsiveness to cues, (3) can explain a wide range of behavioral anomalies, from a cue-triggered present bias to high-frequency variations in social and risk preferences, and (4) can inform the design of managerial interventions and advertising strategies employing environmental cues. Testable restrictions combining choice and nonchoice data fully characterize the model.

This paper was accepted by Manel Baucells, decision analysis.
Falls and older people: preventative interventions
Authors: While Alison E
Published: June 2020

Falls among older people are a major public health challenge, because the sequelae of falls can be severe, both in terms of mental and physical health repercussions. Building on an earlier article that discussed the reasons why older people fall, this article describes the interventions that may help reduce falls among older people. Four interventions which could be applied within UK community settings, namely, the Otago programme, the falls management exercise programme, tai chi and home assessment and modification are outlined here. District nurses are well placed to contribute to a reduction in falls among older people by identifying those susceptible to fall risks among their clients and putting in place the necessary interventions to minimise them.
Experience with setting up community intravenous therapy clinics
Authors: Cowell Sarah , Botes Charlotte
Published: June 2020

The NHS Long Term Plan aims for patients to receive more options, better support and integrated care at the right time and in the optimal care setting. Community nursing teams at the Wirral Community Health and Care NHS Foundation Trust have experienced several challenges in delivering intravenous antibiotics (IV) to patients within their own homes, especially for non-housebound patients, due to the complexity of and demand on the service. Traditionally, intravenous antimicrobials are administered in the acute hospital or in-patient settings. However, there is now a growing trend to deliver intravenous antibiotic therapy within the community. Community nurses have a wealth of knowledge and skills that can support the delivery of the NHS Long Term Plan by developing new models of care in integrated care systems while supporting the implementation and delivery of the governments five-year action plan on antimicrobial resistance. This article describes how the community nursing service at Wirral Community Health and Care NHS Foundation Trust set up community IV clinics.
Propagation analysis and experiment of near-infrared VCSEL-based diffuse optical wireless communication
Authors: Wei Zixian , Mao Simei , Li Zhi , Pepe Alberto , Zhang Li , Liu Xin , Chen Yingjie , Dong Yuhan , Fu H. Y.
Published: June 2020

Diffuse communication plays a more significant role than the usual point-to-point scenario in indoor optical wireless communication (OWC). We present, for the first time to our knowledge, a Monte Carlo simulation and experiment for a 922.39-nm vertical cavity surface-emitting laser array-based non-line-of-sight OWC system with three common reflective materials. The power distribution at the receiver of different reflectors is consistent with the numerical results, proving the validity by separating each reflection into specular and diffuse components. For gigabit Ethernet, all proposed diffuse systems can achieve around 1-GHz bandwidths, and more than 1.25-Gbps data rates over 1-m transmission distance with wide communication coverage. In addition, plastic film and iron plate diffused systems can achieve 2.125-Gbps data rates.
Lensless, reflection-based dark-field microscopy (RDFM) on a CMOS chip
Authors: Imanbekova Meruyert , Perumal Ayyappasamy Sudalaiyadum , Kheireddine Sara , Nicolau Dan V. , Wachsmann-Hogiu Sebastian
Published: June 2020

We present for the first time a lens-free, oblique illumination imaging platform for on-sensor dark- field microscopy and shadow-based 3D object measurements. It consists of an LED point source that illuminates a 5-megapixel, 1.4 µm pixel size, back-illuminated CMOS sensor at angles between 0° and 90°. Analytes (polystyrene beads, microorganisms, and cells) were placed and imaged directly onto the sensor. The spatial resolution of this imaging system is limited by the pixel size (∼1.4 µm) over the whole area of the sensor (3.6×2.73 mm). We demonstrated two imaging modalities: (i) shadow imaging for estimation of 3D object dimensions (on polystyrene beads and microorganisms) when the illumination angle is between 0° and 85°, and (ii) dark-field imaging, at >85° illumination angles. In dark-field mode, a 3-4 times drop in background intensity and contrast reversal similar to traditional dark-field imaging was observed, due to larger reflection intensities at those angles. With this modality, we were able to detect and analyze morphological features of bacteria and single-celled algae clusters.
THz imaging technique for nondestructive analysis of debonding defects in ceramic matrix composites based on multiple echoes and feature fusion
Authors: Zhang Ji-Yang , Ren Jiao-Jiao , Li Li-Juan , Gu Jian , Zhang Dan-Dan
Published: June 2020

We propose a THz nondestructive analysis method based on multiple echoes and feature fusion. Conventionally, it is difficult to identify the debonding defects of the glue layer (II) due to the thin adhesive layer. To this end, a THz propagation model is established, and a quantitative method for determining the thickness of debonding defects based on multiple echoes is presented. The measurement error for preset defect thickness of 500 µm was 4%. Further, for determining the area of debonding defects, a feature fusion imaging algorithm is proposed to realize the lateral recognition of defects and quantitative analysis is used to improve the recognition ability of defects.
All-dielectric nanograting for increasing terahertz radiation power of photoconductive antennas
Authors: Wang Kemeng , Gu Jianqiang , Shi Wenqiao , An Youwen , Li Yanfeng , Tian Zhen , Ouyang Chunmei , Han Jiaguang , Zhang Weili
Published: June 2020

Photoconductive antenna (PCA) is a widely used terahertz (THz) radiation source, but its low radiated power limits the signal-to-noise ratio and bandwidth in THz imaging and spectroscopy applications. Here, we achieved significant PCA power enhancement through etching nanograting directly on the surface of the PCA substrate. The integrated nanograting not only maximizes the generation of photocarriers, but also benefits the bias electric field loaded on the photocarriers. Comparing with the conventional PCA, our PCA realizes a frequency independent THz power enhancement of 3.92 times in the range of 0.05-1.6 THz. Our results reported here not only provide a new method for increasing the THz power of PCAs, but also reveal another way that artificial nanostructures affect the PCAs, which paves the way for the subsequent researches of next-generation PCAs.
Manipulating the scattering pattern with non-Hermitian particle arrays
Authors: Zhang Yun Jing , Li Peng , Galdi Vincenzo , Tong Mei Song , Alù Andrea
Published: June 2020

We show that an array of non-Hermitian particles can enable advanced manipulations of the scattering pattern, beyond what is possible with passive structures. Active linear elements are shown to provide zero forward scattering without sacrificing the total scattered power, and by adding more particles, it is possible to control the zero-scattering direction at will. We apply our theory to realistic implementations of scatterer arrays, using loaded dipole antennas in which we tune the load impedance and investigate the stability of these arrays based on a realistic dispersion model for the gain elements. Finally, we discuss the possibility of controlling multiple frequencies to enable broadband control of the scattering pattern.
Upregulation of annexin A1 protein expression in the intratumoral vasculature of human non–small-cell lung carcinoma and rodent tumor models
Authors: Allen Kevin L. , Cann Jennifer , Zhao Weiguang , Peterson Norman , Lazzaro Michelle , Zhong Haihong , Wu Herren , Dall’Acqua William F. , Borrok M. Jack , Damschroder Melissa M. , Tsui Ping , Li Qing
Published: June 2020

Annexin A1 (anxA1) is an immunomodulatory protein that has been proposed as a tumor vascular target for antitumor biologic agents, yet to date the vascular expression of anxA1 in specific tumor indications has not been systematically assessed. Attempts to evaluate vascular anxA1 expression by immunohistochemistry are complicated by a lack of available antibodies that are both specific for anxA1 and bind the N-terminal–truncated form of anxA1 that has previously been identified in tumor vasculature. To study the vascular expression pattern of anxA1 in non–small-cell lung carcinoma (NSCLC), we isolated an antibody capable of binding N-terminal–truncated anxA127-346 and employed it in immunohistochemical studies of human lung specimens. Lung tumor specimens evaluated with this antibody revealed vascular (endothelial) anxA1 expression in five of eight tumor samples studied, but no vascular anxA1 expression was observed in normal lung tissue. Tumor microarray analysis further demonstrated positive vascular staining for anxA1 in 30 of 80 NSCLC samples, and positive staining of neoplastic cells was observed in 54 of 80 samples. No correlation was observed between vascular and parenchymal anxA1 expression. Two rodent tumor models, B16-F10 and Py230, were determined to have upregulated anxA1 expression in the intratumoral vasculature. These data validate anxA1 as a potential vascular anti-tumor target in a subset of human lung tumors and identify rodent models which demonstrate anxA1 expression in tumor vasculature.
Between authoritarianism and democracy: Examining news media usage for political re-socialization and information acquisition in diasporic contexts
Authors: Arafat Rana Khaled
Published: June 2020

While political scholars study news media as agents of political learning, the processes of political re-socialization of a conflict-generated diaspora moving from authoritarian to democratic regimes pose significant theoretical challenges that remain insufficiently researched. To this end, this study investigates the importance of traditional and digital media sources from the homeland and host country in fostering refugees’ understanding of the democratic norms and values, and political opportunities offered by the receiving country. Furthermore, it investigates the role of online diaspora communities as agents for political re-socialization and tools for information acquisition about Arabic, Swiss and international politics. Sixty semi-structured interviews with Arabs from refugee origins in Switzerland were analysed. Findings show the influence of the early-life political socialization, received prior to forced migration, on the purposive consumption of media from various sources. As Facebook started to lose its value as a source of political information, participants shift to producing and consuming news distributed by strong ties on private WhatsApp groups as a counter-strategy to acquire trustworthy information. Further insights on the impact of perceived media credibility and individual trust in news on the consumption behaviour and political learning are discussed.
‘Globalized difference’: Identity politics on social media
Authors: Vico Sanja
Published: June 2020

By drawing on an ethnographic study of digital communication practices of Serbian Londoners, this article identifies a new form of subtle spontaneous identity politics on social media that seeks to reassert national identity and present it both as an exotic difference and as cosmopolitan. It argues that this form of identity politics has been brought about thanks to social surveillance on social media, the context of London – as a global city – and the particular socio-historical position of the Serbian national identity. Thus, this article contributes to the socio-technical approach to social media, which considers both technical properties of social media and a range of social factors, including users’ agency, in understanding the social consequences of social media. The article concludes that this identity politics is ambivalent in its character – while it is a source of empowerment, it also tends to commodify difference.
Introduction to the diasporic autobiographical documentary
Authors: Scafirimuto Guglielmo
Published: June 2020

This article aims to introduce a new film genre that I call ‘diasporic autobiographical documentary’ that I have been working on during my last years of research, first in France and now in a broader context. In this genre, diasporic cinema and autobiographical documentary meet and create an original ensemble, especially produced in the last twenty years, in order to give place to the search for identity by individuals belonging to more than one nation and culture. In the first part, the present text exposes the principal axes of definition of this body of work, following Raphaëlle Moine’s theory of film genre. In the second part, it deals with two concepts necessary to understand the main issues of this genre: the diasporic subject and the origin. In the search of their lost origin and of their collective memories, diasporic subjects negotiate their identity through the subjective enunciation of the documentary, and offer an important work of reflection on today transnationalism and multiculturalism.
Morphological and physiological changes in papaya seedlings irrigated with saline water and application of humic substances
Authors: Dias Thiago Jardelino , Da Silva Leal Marcia Paloma , Do Nascimento Everaldo Silva , Veras Mario Leno Martins , Silva Toshik Iarley da , Lopes Adriano Salviano
Published: June 2020

In the northeast semiarid region water with high salt content is very common, which may negatively affect crops growth and development. Thus using possible salt stress attenuators is extremely important because it allows the use of saline waters for agricultural purposes. Among the possible attenuators of salt stress, humic substances stand out. This work was driven in order to evaluate the effect of the application of humic substances as a possible attenuator of salt stress from papaya seedlings irrigation. The experiment was conducted under entirely randomized design with five replications in a 4 x 4 factorial, regarding the four doses of humic substances (5, 10, 15 and 20g), and the electrical conductivity of the irrigation water (ECw 1.5; 3.0; 4.5 and 6 dS m-1). When it irrigates the papaya seedlings with water of 6.0 dS m-1 is recommended dose of 20 g of humic substances, which provided growth. Irrigation of papaya seedlings with high salinity (3.0 and 4.5 dS m-1) allied with application of 20 g of humic substances provide increased CO2 concentration, transpiration rate, instantaneous water use efficiency, carboxylation efficiency and chlorophyll b content, however, stomatal conductance, net photosynthesis and chlorophyll a content are reduced with increase of the ECw.
Dormancy overcoming in seeds of cajá-manga (Spondias dulcis)
Authors: Henrique Magalhães de Souza Pedro , Lorrayne Soares Lima Ragagnin Angelita , Carvalho Ribeiro Ricardo , Zildo da Silva Givanildo , Ismael Rocha Diego , Pereira da Silva Danielle Fabíola
Published: June 2020

The propagation of ‘cajá-manga’ (Spondias dulcis) is usually performed by seeds. The presence of dormancy is an obstacle for seedling production and the commercial use of its main product, the fruit. This research aimed to evaluate the use of phytoregulators associated with the scarification of the distal region of the embryo in dormancy overcoming and in the standardization of germination of ‘cajá-manga’ seedlings. Endocarps extracted from fruits of six matrices were subjected to the following treatments: control (T1), mechanic scarification in the distal region of the embryonic axis (T2); all following treatments involved scarification and imbibition in a solution of: water for 6h (T3); GA3 (750 mgL-1) for 6h (T4); GA3 (350 mg L-1) for 12h (T5); Cytokinin (750 mg L-1) for 6h (T6); Cytokinin (350 mg L-1) for 12h (T7); GA3 and Cytokinin (750 mg L-1) for 6h (T8); and GA3 and Cytokinin sowing 25 endocarps in expanded polystyrene trays using a washed sand substrate. The following variables were evaluated: emergence, first emergence count, emergence speed index, mean emergence time, shoot and root length of seedlings, and relative emergence frequency. The experimental design was in randomized blocks, with 9 treatments and four replications consisting of 25 endocarps each. The data obtained were subjected to the F Test at a 1% level of probability, as well as to the Scott-Knott method. The use of mechanic scarification in the opposite region of the embryonic axis, followed by the imbibition in a solution of gibberellin + cytokinin at the concentration of 350 mgL-1 for 12 hours is promising for dormancy overcoming in seeds of Spondias dulcis.
Low Thyroid Function in Nonalcoholic Fatty Liver Disease Is an Independent Predictor of All-Cause and Cardiovascular Mortality
Authors: Kim Donghee , Vazquez-Montesino Luis Miguel , Escober Jessica A. , Fernandes Christopher T. , Cholankeril George , Loomba Rohit , Harrison Stephen A. , Younossi Zobair M. , Ahmed Aijaz
Published: June 2020

INTRODUCTION:

Higher levels of thyroid-stimulating hormone (TSH) in the euthyroid state can negatively affect the metabolic health, including nonalcoholic fatty liver disease (NAFLD). We studied the effect of TSH levels in the setting of normal levels of thyroid hormone on all-cause and cause-specific mortality stratified by NAFLD status.

METHODS:

The National Health and Nutrition Examination Survey (NHANES) III from 1988 to 1994 and NHANES III-linked mortality data through 2015 were used. NAFLD was defined as ultrasonographically diagnosed hepatic steatosis without coexisting liver diseases. Subclinical hypothyroidism was defined as a TSH level over 4.5 mIU/L and “low-normal” thyroid function as higher TSH level (2.5–4.5 mIU/L) within the euthyroid reference range. The Cox proportional hazard model analyzed the all-cause mortality and cause-specific mortality.

RESULTS:

In a multivariate logistic regression analysis, individuals with low thyroid function demonstrated an association with NAFLD in a dose-dependent manner. During a median follow-up of 23 years, low thyroid function was associated with increased all-cause mortality only in the univariate model. Low thyroid function was associated with a higher risk for all-cause mortality in individuals with NAFLD and not in those without NAFLD. Furthermore, low thyroid function was associated with a higher risk for cardiovascular mortality in the entire population and among those with NAFLD but demonstrated no association with the non-NAFLD group.

DISCUSSION:

In this large nationally representative sample of American adults, low thyroid function was associated with NAFLD and a predictor of higher risk for all-cause and cardiovascular mortality in individuals with NAFLD.
Técnicas de planificación de recursos en redes wimax
Authors: Eslava Blanco Hermes Javier , Cadena Muñoz Ernesto , Paez Ingrid Patricia
Published: June 2020

Se presentan los resultados de la investigación orientada a la revisión de la capa física y los algoritmos de planificación en WiMAX: RR, DRR MDRR, WRR, en la asignación de recursos. Se da a conocer un escenario de simulación en donde se tienen una BS, y cinco SS configuradas para generar tráfico de acuerdo a cada una de las clases de servicio soportadas en WiMAX: UGS, nrtPS rtPS, ertPS, BE.Finalmente se exhiben los resultados de simulaciones evaluando el throughput de cada una de las clases de servicio, seleccionando como algoritmos de planificación de recursos: RR, MDRR y PQ.
Software libre: una estrategia para aprender a factorizar
Authors: Pastrán Beltrán José Francisco , Pinzón Herrera Francisco
Published: June 2020

Se presenta el resultado de una investigación acerca de las dificultades de aprendizaje, la desmotivación y el desinterés de los estudiantes en la clase de matemáticas. Se plantea que su proceso de enseñanza y aprendizaje debe dar un giro orientado al uso de las tecnologías de información y comunicación para lograr el mejoramiento de los procesos de aprendizaje, específicamente los procesos de factorización de expresiones algebraicas, a partir de una propuesta basada en la utilización de software libre como estrategia pedagógica, ya que los estudiantes de grado noveno (9º) de la institución educativa departamental San Josemaría Escrivá de Balaguer del municipio de Chía presentan una actitud con alto grado de desinterés, desmotivación y apatía frente al proceso de formación en matemáticas. Por medio del trabajo de campo se verifica la desmotivación y el desinterés de los estudiantes durante la clase de matemáticas y cómo estos aspectos negativos desaparecerían al hacer uso de las TIC.
Soluciones exactas a la ecuación del oscilador de helmholtz para circuitos eléctricos con no linealidad cuadrática
Authors: Salas Alvaro H.
Published: June 2020

en este trabajo se obtiene una solución exacta a la ecuación de Helmholtz con condiciones iniciales y soluciones periódicas acotadas. Esta solución se expresa en términos de la función elíptica de Jacobi cn. Se utiliza esta solución exacta como una semilla para generar una buena aproximación a la solución trigonométrica analítica de la ecuación de Helmholtz para valores de módulo pequeño. Se resuelve numéricamente esta última ecuación y se compara esta solución numérica con la solución analítica obtenida a partir de la solución de la ecuación de Helmholtz. Se dan también algunos ejemplos ilustrativos
Ingeniería clínica y seguridad de la atención en salud
Authors: Caicedo E. Carlos H. , Smida Ali
Published: June 2020

la Ingeniería Clínica es una disciplina en desarrollo que desde 1940 promueve los conceptos, métodos y prácticas de los patrones y principios del apoyo a la atención al paciente aplicando la técnica, la ingeniería y la gestión tecnológica. Actualmente, la Ingeniería Clínica ha cambiado pues los ingenieros no se dedican sólo a evaluar los dispositivos de seguridad eléctrica. Además de la seguridad del paciente y la gestión adecuada de los equipos médicos, los ingenieros han adquirido responsabilidades en otras áreas; no son los que dirigen las oficinas tecnológicas sino que son parte del equipo de gestión del hospital. Durante los últimos años, en Colombia se ha creado una estrategia de gestión de la tecnología orientada en buena medida por el sistema de acreditación. Esto se expresa en normas tales como la tecnología biomédica, dispositivos médicos y el Sistema de aseguramiento de la Calidad de los Servicios de Salud, así como a normas que orientan el sistema de acreditación. Por lo anterior, este artículo analiza el panorama de la ingeniería clínica en la perspectiva de guiar la seguridad del paciente en los hospitales de alta complejidad en Colombia
Agente móvil para transporte de información mediante enlaces ópticos
Authors: Jimenez Róbinson , Bocanegra Rafael , Hernández Rubén D
Published: June 2020

En este trabajo se expone el desarrollo de un agente robotico capaz de desplazarse en trayectorias cerradas sobre supercies planas no regulares. Se dota al agente robótico con un sistema de comunicación óptica para transferencia de información del medio en el que se desenvuelve. El objetivo es desarrollar un agente robótico capaz de desplazarse autónomamente por una supercie, medir parámetros ambientales y transferir dicha información a una fuente remota, a fin de proyectarlo para trabajo colaborativo con agentes de la misma naturaleza en un sistema complejo. Se realizan pruebas de navegabilidad y retorno a la fuente, así como de transferencia de información, a partir de lo cual se obtiene un agente capaz de cumplir con los objetivos propuestos.
Una investigación comparativa entre algoritmos de reglas de asociación
Authors: Rocha Hernández July Andrea , Rodríguez Herrera Diana Milena , Rodríguez Rodríguez Jorge Enrique
Published: June 2020

En este artículo se proponen tres algoritmos para la asociación de datos y se presenta una descripción de cada uno de ellos con el propósito de mostrar cómo realiza las asociaciones que conducen a las reglas de asociación. Posteriormente, se realiza una comparación entre éstos para determinar su eficiencia y efectividad en los resultados. Para lo anterior, se encuentra la complejidad del algoritmo y se evalúa la calidad de los resultados y las reglas generadas. Al mismo tiempo, se utilizan diferentes conjuntos de datos para probar cada algoritmo. Finalmente, se presentan las conclusiones obtenidas en la investigación.
Calibración de filtros de densidad neutra para laboratorios espectrofotométricos
Authors: Vega Gustavo A. , Cubillos Sergio D. , Ruiz Jairo , Nuñez Andrés
Published: June 2020

La normatividad vigente que regula la inspección de gases contaminantes de vehículos diesel exige, sin excepción, el acompañamiento de certificados de calibración a los filtros de densidad neutra. El presente artículo presenta el proceso de investigación para el análisis y diseño de un software especializado en la calibración de lentes de opacidad de densidad neutra (DN), para laboratorios de espectrofotometría. Para lo anterior, se toma como referencia la circular nº 98.00.852.005.1, emanada del Ministerio de Economía francés; y se estructura una prueba consistente con las normas técnicas colombianas NTC 4231 y NTC 17025. Se obtiene así, un software implementado de manera exclusiva In Situ en el laboratorio FENIX TYD para la certificación de calibración de lentes, con precisiones estandarizadas nacionales e internacionales; cumpliéndose la trazabilidad de los patrones y entregando una incertidumbre expandida de 0,04U a 0,45U de la escala fotométrica conforme al requisito normativo que establece el máximo en 0,5U.
Modelo mínimo modificado de la diabetes para simular niveles de glucosa e insulina
Authors: Duitama Leal Alejandro , González Galeano Andrei Alain , Gil Gómez Javier Hernán
Published: June 2020

Debido a la importancia que actualmente tiene la diabetes como enfermedad que se perfila ser una pandemia a nivel mundial, se hace necesario estudiar y comprender, desde difere
Drones: aspectos generales y aplicaciones sociales
Authors: Sánchez Pinzón Byron Felipe , Tapia Ortega José Ricardo , Rosa Paolo
Published: June 2020

Los drones, denominados oficialmente como vehículos aéreos no tripulados, (UAV) por sus siglas en inglés, se caracterizan por no llevar a bordo operador humano, su modelamiento es aerodinámico, por lo que es capaz de mantener un nivel de vuelo controlado y sostenido, y hacerlo autónomamente a través de software o controlado de forma remota. Debido a que su uso se da principalmente, en conflictos bélicos; se hace necesario considerar otros campos de acción que aporten al mejoramiento de la calidad de vida de las comunidades. Por lo anterior, el presente artículo de investigación busca que el lector tenga un panorama sobre aspectos generales y aplicaciones sociales que pueden realizarse con drones, particularmente su evolución, avances, regulación, normas técnicas e implementación en la región Américas; y orientar así la ejecución de futuros proyectos y/o aplicaciones en beneficio de la sociedad y el desarrollo de la región.
Raspberry PI 3 RF signal generation system
Authors: Martínez-Quintero Juan Carlos , Estupiñán-Cuesta Edith Paola , Rodríguez-Ortega Víctor Daniel
Published: June 2020

Radio frequency signal generators (RF) are instruments used to test reception equipment and RF components like filters, amplifiers, attenuators, among others. On the other hand, they reinforce the teaching-learning processes and they are widely used in research in the telecommunications field. This document provides the first stage of a low-cost signal generator design by using RaspBerry Pi 3, with the documentary exploration about this kind of applications. After that, a recognition of the RaspBerry Pi 3 is done at hardware and software level. Finally, an application of an FM signal generator with RaspBerry in a frequency of 101.3 MHz is evaluated, which does not require any additional hardware. This signal was captured using a spectrum analyzer, which determined good quality of the modulated signal in terms of power, bandwidth and SNR (Signal Noise Ratio). However, there are some unwanted harmonic components
Is it still "Big Data" if it fits in my pocket?
Authors: Campbell David
Published: June 2020

"Big Data" is a hot topic but, in many ways, we are still trying to define what the phrase "Big Data" means. For many, there are more questions than answers at this point. Is it about size alone? Complexity? Variability? Data shape? Price/performance? New workloads? New types of users? Are existing data models, data management systems, data languages, and BI/ETL tools relevant in this space? Is MapReduce really a "major step backwards"? I have spent time over the last several years trying to answer many of these questions to my own satisfaction. As part of the journey I have witnessed a number of natural patterns that emerge in big data processing. In this talk I will present a catalog of these patterns and illustrate them across a scale spectrum from megabytes to 100s of petabytes. Finally, I will offer some thoughts around a systems and research agenda for this new world.
Completeness of queries over incomplete databases
Authors: Razniewski Simon , Nutt Werner
Published: June 2020

Data completeness is an important aspect of data quality as in many scenarios it is crucial to guarantee completeness of query answers. We develop techniques to conclude the completeness of query answers from information about the completeness of parts of a generally incomplete database. In our framework, completeness of a database can be described in two ways: by table completeness (TC) statements, which say that certain parts of a relation are complete, and by query completeness (QC) statements, which say that the set of answers of a query is complete. We identify as core problem to decide whether table completeness entails query completeness (TC-QC). We develop decision procedures and assess the complexity of TC-QC inferences depending on the languages of the TC and QC statements. We show that in important cases weakest preconditions for query completeness can be expressed in terms of table completeness statements, which means that these statements identify precisely the parts of a database that are critical for the completeness of a query. For the related problem of QC-QC entailment, we discuss its connection to query determinacy. Moreover, we show how to use the concrete state of a database to enable further completeness inferences.
Structure-aware sampling
Authors: Cohen Edith , Cormode Graham , Duffield Nick
Published: June 2020

In processing large quantities of data, a fundamental problem is to obtain a summary which supports approximate query answering. Random sampling yields flexible summaries which naturally support subset-sum queries with unbiased estimators and well-understood confidence bounds. Classic sample-based summaries, however, are designed for arbitrary subset queries and are oblivious to the structure in the set of keys. The particular structure, such as hierarchy, order, or product space (multi-dimensional), makes
range queries
much more relevant for most analysis of the data.

Dedicated summarization algorithms for range-sum queries have also been extensively studied. They can outperform existing sampling schemes in terms of accuracy on range queries per summary size. Their accuracy, however, rapidly degrades when, as is often the case, the query spans multiple ranges. They are also less flexible---being targeted for range sum queries alone---and are often quite costly to build and use.

In this paper we propose and evaluate variance optimal sampling schemes that are
structure-aware.
These summaries improve over the accuracy of existing
structure-oblivious
sampling schemes on range queries while retaining the benefits of sample-based summaries: flexible summaries, with high accuracy on both range queries and arbitrary subset queries.
Data coordination
Authors: Lawrence Michael , Pottinger Rachel , Staub-French Sheryl
Published: June 2020

In many scenarios, a contingent data source may benefit by coordinating with external heterogeneous sources upon which it depends. The administrator of this contingent source needs to update it when changes are made to the external base sources. For example, when a building design is updated, the contractor's cost estimate must be updated, too. The goal of
data coordination
is to update a contingent source,
C
, based on changes to an independently maintained base source,
B.

This paper introduces a data coordination system which allows
C
to coordinate its data without imposing significant requirements on
B.
Our system uses declarative mappings between
B
and
C
and performs coordination in two stages
View Differencing
--- finding changes to an intermediate view of
B
based on its mapping to
C
, and
Update Translation
--- translating the view differencing result into updates on
C.
We present and evaluate novel solutions to both stages and demonstrate their feasibility on real world problems.