bluuebunny/crossref_metadata_2025 huggingface dataset:
Evidence that Bacteria Packaging by Tetrahymena Is a Widespread Phenomenon
Authors: Durocher Alicia F. , Denoncourt Alix M. , Paquet Valérie E. , Charette Steve J.
Published: October 2020

Protozoa are natural predators of bacteria, but some bacteria can evade digestion once phagocytosed. Some of these resistant bacteria can be packaged in the fecal pellets produced by protozoa, protecting them from physical stresses and biocides. Depending on the bacteria and protozoa involved in the packaging process, pellets can have different morphologies. In the present descriptive study, we evaluated the packaging process with 20 bacteria that have never been tested before for packaging by ciliates. These bacteria have various characteristics (shape, size, Gram staining). All of them appear to be included in pellets produced by the ciliates Tetrahymena pyriformis and/or T. thermophila in at least one condition tested. We then focused on the packaging morphology of four of these bacteria. Our results demonstrated that, as shown previously for Mycobacterium smegmatis, the packaging of Microbacterium oxydans, Micrococcus luteus, and Cupriavidus sp. was formed of a single layer of material. The packaging of Cellulosimicrobiumfunkei was made of indistinguishable material. A different pellet morphology was obtained for each of the four bacterial strains studied. The ingestion of small bacteria resulted in rounder, denser, and more regular pellets. These results support the idea that bacteria packaging is a relatively widespread phenomenon.
Comparison of the Pathogenicity of Classical Swine Fever Virus Subgenotype 2.1c and 2.1d Strains from China
Authors: Hao Genxi , Zhang Huawei , Chen Huanchun , Qian Ping , Li Xiangmin
Published: October 2020

Classical swine fever (CSF) caused by classical swine fever virus (CSFV) is a highly contagious and devastating disease. The traditional live attenuated C-strain vaccine is widely used to control disease outbreaks in China. Since 2000, subgenotype 2.1 has become dominant in China. Here, we isolated subgenotype 2.1c and 2.1d strains from CSF-suspected pigs. The genetic variations and pathogenesis of subgenotype 2.1c and 2.1d strains were investigated experimentally. We aimed to evaluate and compare the replication characteristics and clinical signs of subgenotype 2.1c and 2.1d strains with those of the typical highly virulent CSFV SM strain. In PK-15 cells, the three CSFV isolates exhibited similar replication levels but significantly lower replication levels compared with the CSFV SM strain. The experimental animal infection model showed that the pathogenicity of subgenotype 2.1c and 2.1d strains was less than that of the CSFV SM strain. According to the clinical scoring system, subgenotype 2.1c (GDGZ-2019) and 2.1d (HBXY-2019 and GXGG-2019) strains were moderately virulent. This study showed that the pathogenicity of CSFV field strains will aid in the understanding of CSFV biological characteristics and the related epidemiology.
Effects of Alginate and Chitosan on Activated Carbon as Immobilisation Beads in Biohydrogen Production
Authors: Dzul Rashidi Nur Farahana , Jamali Nur Syakina , Mahamad Siti Syazwani , Ibrahim Mohamad Faizal , Abdullah Norhafizah , Ismail Siti Fatimah , Siajam Shamsul Izhar
Published: October 2020

In this study, the effects of alginate and chitosan as entrapped materials in the biofilm formation of microbial attachment on activated carbon was determined for biohydrogen production. Five different batch fermentations, consisting of mixed concentration alginate (Alg), were carried out in a bioreactor at temperature of 60 °C and pH 6.0, using granular activated carbon (GAC) as a primer for cell attachment and colonisation. It was found that the highest hydrogen production rate (HPR) of the GAC–Alg beads was 2.47 ± 0.47 mmol H2/l.h, and the H2 yield of 2.09 ± 0.22 mol H2/mol sugar was obtained at the ratio of 2 g/L of Alg concentration. Next, the effect of chitosan (C) as an external polymer layer of the GAC–Alg beads was investigated as an alternative approach to protecting the microbial population in the biofilm in a robust environment. The formation of GAC with Alg and chitosan (GAC–AlgC) beads gave the highest HPR of 0.93 ± 0.05 mmol H2/l.h, and H2 yield of 1.11 ± 0.35 mol H2/mol sugar was found at 2 g/L of C concentration. Hydrogen production using GAC-attached biofilm seems promising to achieve consistent HPRs at higher temperatures, using Alg as immobilised bead material, which has indicated a positive response in promoting the growth of hydrogen-producing bacteria and providing excellent conditions for microorganisms to grow and colonise high bacterial loads in a bioreactor.
Enhanced Degradation of Phenolic Compounds in Coal Gasification Wastewater by Methods of Microelectrolysis Fe-C and Anaerobic-Anoxic—Oxic Moving Bed Biofilm Reactor (A2O-MBBR)
Authors: Huong Do Tra , Nguyen Van Tu , Ha Xuan Linh , Nguyen Thi Hien Lan , Duong Thi Thoa , Nguyen Duy Chinh , Nguyen Thi Hong-Tham
Published: October 2020

The coal gasification wastewater figures prominently among types of industrial effluents due to its complex and phenolic composition, posing great difficulty for conventional water treatment processes. Since the coking wastewater is toxic and mutagenic to humans and animals, treatment of coal gasification wastewater is genuinely necessary. In this study, we established a lab-scale A2O (Anaerobic-Anoxic—Oxic) with moving bed biological reactor (MBBR) system and evaluated some water indicators of wastewater pretreated with internal electrolysis, of wastewater output of the established A2O-MBBR system, and of the wastewater treated by the combination thereof. The wastewater was taken from a coking plant at Thai Nguyen Iron and Steel Joint Stock Company in Vietnam. COD, BOD5, NH4+-N, phenol, and pH of the input coal gasification wastewater were 2359, 1105, 319, 172 mg/L, and 8 ± 0.1, respectively. The conditions of internal electrolysis were as follows: 720 min of reaction time, pH = 4, 25 g/L Fe-C dosage, and 100 mg/L PAM dosage. After internal electrolysis process, the removal of COD, BOD5, NH4+-N, and phenol were 53.7%, 56.7% 60.5%, and 73.3%, respectively. After 24 h of treatment, the treatment efficiencies of the combined treatment process are as follows: 100% phenol removal, 71.3% of TSS removal; 97.7% reduction of BOD5, and 97.1% reduction of COD; total N content reduced by 97.6%; total P content decreased by 81.6%; and NH4+-N content decreased by 97.5%. All above indicators after treatment have met QCVN 52: 2017/BTNMT (column A) Vietnamese standard for steel industry wastewater.
Effect of Water Dilution on Full-Arch Gypsum Implant Master Casts
Authors: Sheets James , Wee Alvin , Simetich Bobby , Beatty Mark
Published: October 2020

The objective of this study was to assess if the setting expansion, compressive strength, compressive modulus and Knoop hardness is reduced in Type III, IV and V gypsum products when excess water is added to recommended water/powder (W/P) ratios for full-arch implant master casts. Four properties were measured: linear setting expansion, compressive strength, compressive modulus, and Knoop hardness. Three dental stones were evaluated: ISO Type III, Type IV, and Type V. Water was added to recommended W/P ratios as follows: (1) 0%, the manufacturer’s recommend W/P ratio, (2) 50%, 1.5 times the manufacturer’s recommendation of water, (3) 100%, three times the manufacturer’s recommendation of water, (4) 150%, 2.5 times the manufacturer’s recommendation of water, and (5) 200%, three times the manufacturer’s recommendation of water. For all three gypsum types, 50% water additions minimally affected the setting expansion and compressive modulus (p > 0.05), but lowered compressive strength by 26% to 52% (p < 0.05). Knoop hardness was lowered by 24% and 48% for Types V and III (p < 0.05), whereas Type IV was not significantly affected (p > 0.05). With few exceptions, the physical properties for the three gypsum types reached minimum values at 100% dilution, with few changes noted at higher dilutions. Increased W/P ratios did not adequately reduce the setting expansion and adversely affected other physical properties. Of the gypsums tested, Type IV is still recommended due to its lower setting expansion for full-arch implant master casts.
Grouped Normal Variance Mixtures
Authors: Hintz Erik , Hofert Marius , Lemieux Christiane
Published: October 2020

Grouped normal variance mixtures are a class of multivariate distributions that generalize classical normal variance mixtures such as the multivariate t distribution, by allowing different groups to have different (comonotone) mixing distributions. This allows one to better model risk factors where components within a group are of similar type, but where different groups have components of quite different type. This paper provides an encompassing body of algorithms to address the computational challenges when working with this class of distributions. In particular, the distribution function and copula are estimated efficiently using randomized quasi-Monte Carlo (RQMC) algorithms. We propose to estimate the log-density function, which is in general not available in closed form, using an adaptive RQMC scheme. This, in turn, gives rise to a likelihood-based fitting procedure to jointly estimate the parameters of a grouped normal mixture copula jointly. We also provide mathematical expressions and methods to compute Kendall’s tau, Spearman’s rho and the tail dependence coefficient λ. All algorithms presented are available in the R package nvmix (version ≥ 0.0.5).
Recent Climate Change Feedbacks to Greenland Ice Sheet Mass Changes from GRACE
Authors: Zou Fang , Tenzer Robert , Fok Hok Sum , Nichol Janet E.
Published: October 2020

Although a significant effort has been dedicated to studying changes in the mass budget of the Greenland Ice Sheet (GrIS), mechanisms behind these changes are not yet fully understood. In this study, we address this issue by investigating the link between climate controls and mass changes of the GrIS between August 2002 and June 2017. We estimate the GrIS mass changes based on averaging the Gravity Recovery and Climate Experiment (GRACE) monthly gravity field solutions from four processing data centers. We then investigate the possible impact of different climate variables on the GrIS mass changes using the North Atlantic Oscillation (NAO), temperature, precipitation, and the 700 hPa wind retrieved from the ERA-5 reanalysis. Results indicate a decrease of −267.77 ± 32.67 Gt/yr in the total mass of the GrIS over the 16-year period. By quantifying the relationship between climate controls and mass changes, we observe that mass changes in different parts of Greenland have varying sensitivity to climate controls. The NAO mainly controls mass changes in west Greenland, where the summertime NAO modulations have a greater impact on the summer mass loss than the wintertime NAO modulations have on the winter mass gain. The GrIS mass changes are correlated spatially with summer temperature, especially in southwest Greenland. Mass balance changes in northwest Greenland are mostly affected by wind anomalies. These new findings based on wind anomalies indicate that the summer atmospheric circulation anomalies control surface temperature and snow precipitation and consequently affect mass changes in different parts of Greenland.
sUAS Remote Sensing of Vineyard Evapotranspiration Quantifies Spatiotemporal Uncertainty in Satellite-Borne ET Estimates
Authors: Kalua Michael , Rallings Anna M. , Booth Lorenzo , Medellín-Azuara Josué , Carpin Stefano , Viers Joshua H.
Published: October 2020

Small Unmanned Aerial Systems (sUAS) show promise in being able to collect high resolution spatiotemporal data over small extents. Use of such remote sensing platforms also show promise for quantifying uncertainty in more ubiquitous Earth Observation System (EOS) data, such as evapotranspiration and consumptive use of water in agricultural systems. This study compares measurements of evapotranspiration (ET) from a commercial vineyard in California using data collected from sUAS and EOS sources for 10 events over a growing season using multiple ET estimation methods. Results indicate that sUAS ET estimates that include non-canopy pixels are generally lower on average than EOS methods by >0.5 mm day−1. sUAS ET estimates that mask out non-canopy pixels are generally higher than EOS methods by <0.5 mm day−1. Masked sUAS ET estimates are less variable than unmasked sUAS and EOS ET estimates. This study indicates that limited deployment of sUAS can provide important estimates of uncertainty in EOS ET estimations for larger areas and to also improve irrigation management at a local scale.
An Ensemble Learning Approach for Urban Land Use Mapping Based on Remote Sensing Imagery and Social Sensing Data
Authors: Huang Zhou , Qi Houji , Kang Chaogui , Su Yuelong , Liu Yu
Published: October 2020

Urban land use mapping is crucial for effective urban management and planning due to the rapid change of urban processes. State-of-the-art approaches rely heavily on the socioeconomic, topographical, infrastructural and land cover information of urban environments via feeding them into ad hoc classifiers for land use classification. Yet, the major challenge lies in the lack of a universal and reliable approach for the extraction and combination of physical and socioeconomic features derived from remote sensing imagery and social sensing data. This article proposes an ensemble-learning-approach-based solution of integrating a rich body of features derived from high resolution satellite images, street-view images, building footprints, points-of-interest (POIs) and social media check-ins for the urban land use mapping task. The proposed approach can statistically differentiate the importance of input feature variables and provides a good explanation for the relationships between land cover, socioeconomic activities and land use categories. We apply the proposed method to infer the land use distribution in fine-grained spatial granularity within the Fifth Ring Road of Beijing and achieve an average classification accuracy of 74.2% over nine typical land use types. The results also indicate that our model outperforms several alternative models that have been widely utilized as baselines for land use classification.
Does the Position of Foot-Mounted IMU Sensors Influence the Accuracy of Spatio-Temporal Parameters in Endurance Running?
Authors: Zrenner Markus , Küderle Arne , Roth Nils , Jensen Ulf , Dümler Burkhard , Eskofier Bjoern M.
Published: October 2020

Wearable sensor technology already has a great impact on the endurance running community. Smartwatches and heart rate monitors are heavily used to evaluate runners’ performance and monitor their training progress. Additionally, foot-mounted inertial measurement units (IMUs) have drawn the attention of sport scientists due to the possibility to monitor biomechanically relevant spatio-temporal parameters outside the lab in real-world environments. Researchers developed and investigated algorithms to extract various features using IMU data of different sensor positions on the foot. In this work, we evaluate whether the sensor position of IMUs mounted to running shoes has an impact on the accuracy of different spatio-temporal parameters. We compare both the raw data of the IMUs at different sensor positions as well as the accuracy of six endurance running-related parameters. We contribute a study with 29 subjects wearing running shoes equipped with four IMUs on both the left and the right shoes and a motion capture system as ground truth. The results show that the IMUs measure different raw data depending on their position on the foot and that the accuracy of the spatio-temporal parameters depends on the sensor position. We recommend to integrate IMU sensors in a cavity in the sole of a running shoe under the foot’s arch, because the raw data of this sensor position is best suitable for the reconstruction of the foot trajectory during a stride.
A Comparative Analysis of Hybrid Deep Learning Models for Human Activity Recognition
Authors: Abbaspour Saedeh , Fotouhi Faranak , Sedaghatbaf Ali , Fotouhi Hossein , Vahabi Maryam , Linden Maria
Published: October 2020

Recent advances in artificial intelligence and machine learning (ML) led to effective methods and tools for analyzing the human behavior. Human Activity Recognition (HAR) is one of the fields that has seen an explosive research interest among the ML community due to its wide range of applications. HAR is one of the most helpful technology tools to support the elderly’s daily life and to help people suffering from cognitive disorders, Parkinson’s disease, dementia, etc. It is also very useful in areas such as transportation, robotics and sports. Deep learning (DL) is a branch of ML based on complex Artificial Neural Networks (ANNs) that has demonstrated a high level of accuracy and performance in HAR. Convolutional Neural Networks (CNNs) and Recurrent Neural Networks (RNNs) are two types of DL models widely used in the recent years to address the HAR problem. The purpose of this paper is to investigate the effectiveness of their integration in recognizing daily activities, e.g., walking. We analyze four hybrid models that integrate CNNs with four powerful RNNs, i.e., LSTMs, BiLSTMs, GRUs and BiGRUs. The outcomes of our experiments on the PAMAP2 dataset indicate that our proposed hybrid models achieve an outstanding level of performance with respect to several indicative measures, e.g., F-score, accuracy, sensitivity, and specificity.
How Do Newly-Amended Biochar Particles Affect Erodibility and Soil Water Movement?—A Small-Scale Experimental Approach
Authors: Seitz Steffen , Teuber Sandra , Geißler Christian , Goebes Philipp , Scholten Thomas
Published: October 2020

Biochar amendment changes chemical and physical properties of soils and influences soil biota. It is, thus, assumed that it can also affect soil erosion and erosion-related processes. In this study, we investigated how biochar particles instantly change erodibility by rain splash and the initial movement of soil water in a small-scale experiment. Hydrothermal carbonization (HTC)-char and Pyrochar were admixed to two soil substrates. Soil erodibility was determined with Tübingen splash cups under simulated rainfall, soil hydraulic conductivity was calculated from texture and bulk soil density, and soil water retention was measured using the negative and the excess pressure methods. Results showed that the addition of biochar significantly reduced initial soil erosion in coarse sand and silt loam immediately after biochar application. Furthermore, biochar particles were not preferentially removed from the substrate surface, but increasing biochar particle sizes partly showed decreasing erodibility of substrates. Moreover, biochar amendment led to improved hydraulic conductivity and soil water retention, regarding soil erosion control. In conclusion, this study provided evidence that biochar amendments reduce soil degradation by water erosion. Furthermore, this effect is detectable in a very early stage, and without long-term incorporation of biochar into soils.
Factors Associated with Travel Behavior of Millennials and Older Adults: A Scoping Review
Authors: Jamal Shaila , Newbold K. Bruce
Published: October 2020

This study aims to synthesize knowledge on the travel behavior of millennials and older adults based on literature from 2010 to 2018. The study looks into the different factors that contributed to shaping each generation’s travel behavior. Both qualitative and quantitative studies that fall within the selection criteria are reviewed, with a total of seventy-eight studies selected for review. Thirty-four papers focused on young adults/millennials, 35 included an older adult population, and 9 investigated both younger and older age groups. Six of the studies utilized qualitative methods, 68 applied quantitative methods, and 4 used mixed methods to explore the factors associated with travel behavior. Travel behaviors are explored in terms of mode choice, trip distance, trip frequency, use of alternative transport, ridesharing, and mobility tool ownership. Associated factors are categorized into five themes: personal attributes, geography and built environment, living arrangements and family life, technology adoption, and perceptions and attitudes towards travel options and environment. This study concludes that difference exists between generations in terms of travel behavior, and that the factors that influence each generation’s travel characteristics are either different or differ in their nature of influence (increase/decrease). Finally, based on the reviewed literature, this study proposes future research directions.
Managing ICT for Sustainable Education: Research Analysis in the Context of Higher Education
Authors: González-Zamar Mariana-Daniela , Abad-Segura Emilio , López-Meneses Eloy , Gómez-Galán José
Published: October 2020

The use of information and communication technologies (ICTs) for the benefit of the environment favors the development of a sustainable education, which will help to train more responsible and aware students. The management of educational technology in the context of a sustainable higher education must achieve the internalization of ethics and the sustainable development of humanity. The main objective of this study is to, at a global level, examine the research during the period 2000–2019 on the management of ICTs for sustainable education in the context of higher education. Global research trends on this topic during the period 2000–2019 have been analyzed. Consequently, bibliometric techniques have been applied to a sample of 1814 articles selected from the Scopus database. The results provided data on the scientific productivity of the journal, authors, research institutions, and countries that contribute to the development of this topic. The evidence reveals an exponential trend, mainly in the last five years. In addition, current and future lines of research have been identified. Research at an international level presents a growing trend of publication that allows determination of the relevance of research on ICT management to achieve sustainable education in the context of higher education. This study makes it possible to establish the relationship between science, sustainability, and technology in higher education institutions, and to base the decision-making process for the driving agents of this area of knowledge.
On the Degeneracy of the Orbit Polynomial and Related Graph Polynomials
Authors: Ghorbani Modjtaba , Dehmer Matthias , Emmert-Streib Frank
Published: October 2020

The orbit polynomial is a new graph counting polynomial which is defined as OG(x)=∑i=1rx|Oi|, where O1, …, Or are all vertex orbits of the graph G. In this article, we investigate the structural properties of the automorphism group of a graph by using several novel counting polynomials. Besides, we explore the orbit polynomial of a graph operation. Indeed, we compare the degeneracy of the orbit polynomial with a new graph polynomial based on both eigenvalues of a graph and the size of orbits.
Pengaruh Attraction, Accessibillity, Amenity, Ancillary Terhadap Kepuasan Generasi Millenial Berkunjung ke Tempat Wisata
Authors: Alvianna Stella , Patalo Ryan Gerry , Hidayatullah Syarif , Rachmawati Ike Kusdyah
Published: October 2020

Indonesia has various regions with potential tourism attractions that can attract tourists, one of them is Malang City, where Malang City is also known as one of the main tourist destinations in Indonesia. This study illustrates the influence of the components of tourism products consisting of attractions, access, amenities and ancillary to the decision of visiting tourists, especially millennial generation in the Tlogowaru mask tourism village of Malang. Topeng Village which is one of the tourist destinations in the form of thematic villages with the theme of Malangan Mask that has been around since the year 2016. The population of this study is all students of the Unmer Tourism Tourism Program Malang who entered the millennial age (aged between 15-34 years) with a sample of 60 people based on their characteristics visited Malangan mask village. Data analysis used multiple linear regression and hypothesis testing. The results of the research show that attraction and ancillary have a positive and significant effect on customer satisfaction. This shows the perception of what tourists get and what tourists feel can have a positive impact and also the presence of officers on guard, the presence of security posts and the existence of a tourist information center that continues to be maintained and improved, also has a positive impact on tourist attractions.
Methods of teaching gymnastic exercises to students engaged in sports aerobics
Authors: Kravchuk T.M. , Bybel S.A. , Slastina O.O. , Kovalenko A.I.
Published: October 2020

The aim - to substantiate and experimentally test the method of teaching gymnastic exercises to students engaged in sports aerobics. 
Material and methods. The study involved 20 students of Kharkiv institutions of higher education engaged in sports aerobics in groups of sports improvements. At the time of the experiment, the subjects were 17 to 20 years old. Method of research. Theoretical analysis and generalization of scientific and methodological literature; analysis of rules and videos of competitions; pedagogical experiment; expert evaluation; methods of mathematical statistics. 
Results. As a result of the study, a method of teaching and improving the technique of performing gymnastic exercises for students of higher educational institutions specializing in sports aerobics was developed. It is proved that the introduction in the educational and training process of students engaged in sports aerobics, special exercises that gradually lead to the implementation of gymnastic elements, and at the same time partially develop the necessary physical abilities contribute to their more effective assimilation and improvement. In particular, the execution quality control all gymnastic exercises (emphasis angle flairs out with 360° rotation; emphasis high angle; planche apart the legs; sagittal balance with the grip on the leg and rotate 360°; libel spin with the prop hands on the floor) in the experimental group, unlike the control, increased on average by 50%. 
Conclusions. Thus, the paper highlights the main groups of gymnastic elements provided by the current rules of competition in sports aerobics. The method of training students specializing in sports aerobics to perform these elements is developed. Experimental verification of the effectiveness of the developed technique was carried out.
The ability to punch in the front for students of pencak silat uns achievement (Correlational Study Viewed from Eye-Hand Coordination, Arm Length and Arm Power)
Authors: Bahrul Ulum Muhammad , Agus Kristiyanto , Riyadi Slamet
Published: October 2020

The aim  of this study was to determine the interaction of eye-hand coordination, arm length and arm power with the ability to punch in front of the students of UNS Pencak Silat achievement coaching.

Material and methods. The design or research design used is to use descriptive methods with correlational study techniques (correlation design). This research will describe the relationship and the amount of contribution between eye-hand coordination, arm length and arm power with the ability to punch ahead in the Pencak Silat sport. The population in this study were all students of UNS pencak silat achievement coaching which included fostering the achievements of the Faculty of sport, Tapak Suci student activity units, PSHT student activity units, Merpati Putih student activity units and student self-defense units.

Results. Based on the results of research and the results of data analysis that has been done, the following conclusions can be obtained: There is a significant relationship between eye-hand coordination, arm length and arm power with the ability to punch in front of pencak silat with a significant value F count = 64,99 > F table = 2,81.

Conclusions.  Contribution of eye-hand coordination is the variable that has the most dominant contribution, then followed by the arm power variable and the smallest contribution is the arm length variable. Meanwhile the remaining 19.1% is contributed by factors other than those represented by independent variables. Predictions from researchers of these other factors could have been influenced by training factors or other physical condition factors that also supported the ability to punch in front of pencak silat.
Abraham, Carlos (ed.). El cuento fantástico en Caras y Caretas. Volumen II. Buenos Aires: Cuadernos de la Gran Aldea, 2018.
Authors: Martínez Vela Marlon
Published: October 2020

Las publicaciones periódicas brindan la oportunidad de explorar diferentes aspectos de un periodo determinado: gustos, modas, géneros literarios preferidos, textos de escritores conocidos y otros sin el oropel de la canonicidad, pero que demuestran ser verdaderas joyas perdidas porque sus autores naufragaron en la memoria de los años. Eso es precisamente lo que puede encontrar el lector del gran trabajo de Carlos Abraham en El cuento fantástico en Caras y Caretas. Volumen II...
COMPUESTOS VOLÁTILES RESPONSABLES DEL SABOR DEL TOMATE
Authors: Dávila-Aviña Jorge E. de J. , González-Aguilar Gustavo A. , Ayala-Zavala Jesús F. , Sepúlveda David R. , Olivas Guadalupe I.
Published: October 2020

La producción de frutos de tomate (Lycopersicon esculentum Mill.) con sabor agradable está recibiendo atención especial, porque este atributo se ha convertido en uno de los principales parámetros de calidad en la aceptación de frutas y hortalizas. Aquí se analiza cómo los compuestos volátiles influyen significativamente en el sabor del tomate, por ser responsables de su aroma. Los principales compuestos volátiles del tomate involucran a aldehídos, alcoholes, cetonas y ésteres insaturados de cadenas cortas, los cuales son producidos a partir de ácidos grasos, aminoácidos libres y carotenoides. Entre las principales enzimas involucradas se encuentran lipoxigenasa, hidroperoxidoliasa y alcohol deshidrogenasa para la biosíntesis de volátiles a partir de ácidos grasos; además están las enzimas aminotransferasa, descarboxilasa y alcohol deshidrogenasa, relacionadas con la biosíntesis de volátiles derivados de aminoácidos. La composición y concentración de los compuestos volátiles depende de factores genéticos, así como de las condiciones de cultivo y del almacenamiento. El presente manuscrito compila y analiza la información actual referente a la biosíntesis de los volátiles que definen el aroma del tomate, así como sus rutas metabólicas, enzimas y sustratos involucrados; así mismo analiza los principales factores precosecha, cosecha y poscosecha que afectan su biosíntesis.
COMPOSICIÓN DEL ACEITE ESENCIAL DE Tagetes parryi A. GRAY
Authors: Díaz-Cedillo Francisco , Serrato-Cruz Miguel A.
Published: October 2020

Es escasa la información sobre los compuestos químicos presentes en el aceite esencial de las especies mexicanas de Tagetes. Mediante hidrodestilación se extrajo aceite esencial de las partes aéreas de plantas de Tagetes parryi A. Gray (Asteraceae), planta endémica en el estado de San Luis Potosí, México. Mediante análisis por cromatografía de gases acoplada a espectrometría de masas, se identificaron siete compuestos principales en el aceite esencial con la siguiente abundancia relativa: canfeno (96 %), 3, 6, 6-trimetil-2-norpinanol (91 %), anisol (60 %), 4-isopropil-1-metil-2-ciclohexenol (50 %), cineol (48 %), eugenol (14 %) y α-terpineol (12 %). El segundo y cuarto compuestos no se habían descrito para Tagetes.
‘V-55 A’, VARIEDAD DE MAÍZ DE GRANO AMARILLO PARA LOS VALLES ALTOS DE MÉXICO
Authors: Espinosa-Calderón Alejandro , Tadeo-Robledo Margarita , Gómez-Montiel Noel , Sierra-Macías Mauro , Virgen-Vargas Juan , Palafox-Caballero Artemio , Caballero-Hernández Filiberto , Vázquez-Carrillo Gricelda , Rodríguez-Montalvo Flavio A. , Valdivia-Bernal Roberto , Arteaga-Escamilla Israel , González-Rojo Isaías
Published: October 2020

En los Valles Altos de la Mesa Central de México ubicados en altitudes de 2200 a 2600 m, se cultivan cerca de 1.5 millones de hectáreas con maíz (Zea mays L.), superficie que representa 20 % de la establecida en el país con esta especie (Turrent, 1994; Ávila et al., 2009). De esta extensión, 800 mil hectáreas se cultivan en condiciones de temporal (secano), el cual generalmente inicia tarde, lo que restringe la fecha de siembra y la productividad del cultivo.
GENETIC DIVERSITY AND DIFFERENTIATION OF Pseudotsuga menziesii (Mirb.) Franco POPULATIONS IN MÉXICO
Authors: Cruz-Nicolás Jorge , Vargas-Hernández J. Jesús , Ramírez-Vallejo Porfirio , López-Upton Javier
Published: October 2020

Mexican populations of Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] constitute valuable gene pools for conservation and breeding programs of this species. Genetic diversity and population divergence were estimated using 18 isozyme loci and samples from 11 natural Douglas-fir populations in México. Genetic diversity was high at the species level (83.3 % polymorphic loci and 2.9 alleles per locus), but low at the population level (28.3 % polymorphic loci and 1.52 alleles per locus), particularly for populations from central México. A high level of population differentiation was found (Fst = 0.298), indicating that each population shares only a small fraction of the genetic diversity within the species and that genetic drift might have an important role in shaping the structure of genetic diversity in these populations. Genetic distances among populations in the Sierra Madre Oriental were positively correlated with geographic distances (r = 0.849), but the association was not significant according to the Mantel test. Populations from northeastern México separated from all others, whereas population Mohinora from northwestern México, joined those from central México. These results emphasize the priority for in situ conservation of Douglas-fir populations in central México.
CAÍDA DE HOJARASCA EN PLANTACIONES DE Pinus greggii Engelm. Y Pinus cembroides Zucc., EN COAHUILA, MÉXICO
Authors: Gutiérrez-Vázquez Mario H. , Méndez-González Jorge , Flores-López Celestino , Ramírez-Díaz José A. , Gutiérrez-Vázquez Benito N.
Published: October 2020

Esta investigación se llevó a cabo para evaluar la caída de hojarasca en dos plantaciones forestales (Pinus greggii Engelm. y P. cembroides Zucc.) establecidas en el año de 1992 en la Sierra de Arteaga, Coahuila, México, ambas en condiciones ambientales de crecimiento similares. La hojarasca fue colectada mensualmente durante un año (febrero 2009 – febrero 2010), en 15 trampas distribuidas aleatoriamente en cada plantación. Las trampas de 1 m2 fueron construidas de madera, con una malla metálica de 1 mm x 1 mm en el fondo. La prueba no paramétrica de Kruskal-Wallis (95 %) se usó para detectar diferencias estadísticas en la caída de componentes de hojarasca (hojas, ramas y conos masculinos), entre especies y fechas de colecta. Para evaluar la relación de la caída de hojarasca y factores climáticos se hicieron análisis de componentes principales y de regresión paso a paso (Stepwise). Los promedios de caída de hojarasca fueron estadísticamente más altos (P < 0.05) en P. greggii (2.98 ± 5.18 g m-2/mes) que en P. cembroides (2.71 ± 6.01 g m-2/mes), y equivalentes a 1072 y 976 kg ha-1/año, respectivamente. Las hojas representaron 92.3 ± 8.1 % de la hojarasca en P. greggii y 94.3 ± 3.8 % en P. cembroides. Los resultados indican que la caída de hojarasca es dependiente de la especie, así como de factores climáticos, en especial de viento y temperatura.
ESTADO HÍDRICO Y CAMBIOS ANATÓMICOS EN LA CALABACITA (Cucurbita pepo L.) ALMACENADA
Authors: Urías-Orona Vania , Muy-Rangel Dolores , Osuna-Enciso Tomás , Sañudo-Barajas Adriana , Báez-Sañudo Manuel , Valdez-Torres Benigno , Siller-Cepeda Jorge , Campos-Sauceda Juan
Published: October 2020

El fruto de calabacita (Cucurbita pepo L.) es una hortaliza que presenta elevada actividad metabólica, alta transpiración y sensibilidad a daños mecánicos en postcosecha. En este estudio se evaluó el efecto de la temperatura de almacenamiento en el estado hídrico, la integridad celular y la calidad postcosecha de frutos de calabacita tipo Zucchini cv. ‘Raben’. Frutos cosechados en madurez hortícola se almacenaron por 12 d a 10 y 20 °C, y 85 a 87 % de humedad relativa. Se evaluó pérdida de peso, marchitamiento, contenido relativo de agua (CRA), potencial hídrico (Ψw), potencial osmótico (Ψs), potencial de presión (Ψp) e integridad celular mediante un estudio histológico de los frutos. Los primeros síntomas de marchitez del fruto aparecieron cuando hubo 6 % de pérdida de peso. La plasmólisis celular se presentó entre 81 y 82 % de CRA, con un Ψp igual a cero y con Ψw y Ψs iguales a -0.8 MPa. La integridad del tejido se afectó por la pérdida de adhesión de las células de la zona del endocarpio, que luego progresó hacia el epicarpio del fruto.
Potencial de aprendizaje y evaluación dinámica de la zona de aprendizaje próximo en niños pequeños (2 a 4 años)
Authors: Bonofiglio Leandra
Published: October 2020

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El fracaso escolar en contextos urbanos críticos. Heredarás la vergüenza
Authors: Rosbaco Inés Cristina
Published: October 2020

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Aproximación a la transmisión de saberes en la historia del INTA Santa Fe
Authors: Moscatelli Mirta , Tomino Gaspar
Published: October 2020

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La investigación en educación artística en la Argentina: estado del arte. Un abordaje desde el relevamiento nacional de investigaciones educativas
Authors: Pozzo María Isabel
Published: October 2020

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Presentación
Authors: Zamudio María Verónica
Published: October 2020

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REACCIONES Y OPOSICIONES EN ESCUELAS SECUNDARIAS DEL ÁREA METROPOLITANA DE BUENOS AIRES
Authors: Langer Eduardo
Published: October 2020

En este artículo se caracterizan las reacciones y oposiciones de estudiantes enescuelas secundarias en contextos de pobreza urbana del área de la región metropolitana de Buenos Aires, en un marco en el que los actuales sistemas de regulación y las formas de sancionar las conductas en las instituciones se flexibilizan. Ello se realiza, fundamentalmente, en términos de la sanción y control del tiempo, del espacio, de la tarea, de la actividad escolar y más, específiamente, respecto de las formas de relación con los adultos. Partimos del supuesto que las situaciones cotidianas y los modos de vida de los estudiantes en contextos de pobreza urbana se tensionan con las dinámicas escolares porque, de hecho, esas reacciones y oposiciones implican “un devenir que abre un proceso de creación, de transformación de la situación”. (Lazzarato, 2006: 50).
I CONGRESO DEL PROGRAMA NO GRADUADO, SANTA FE: OTRA FORMA DE PENSAR Y HACER LA ESCUELA
Authors: Sokolowicz Dana
Published: October 2020

La siguiente reseña presenta el I Congreso del Programa No Graduado de SantaFe. Este programa implementa una modalidad de enseñanza diferente al aula estándar.Al desarrollar los temas tratados en el mismo, esta reseña contribuirá a enriquecer eldebate sobre las condiciones pedagógicas de la escolarización hoy, al mismo tiempoque permitirá difundir prácticas pedagógicas escolares más inclusivas.
La pragmatización del conocimiento en la universidad "modernizada". Otros significados y acciones en fragmentos de nuestra memoria colectiva
Authors: Carnevale María Josefina
Published: October 2020

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El fracaso escolar. ¿Un problema del alumno o de la institución?
Authors: Maire María Laura , Yurkovich Adriana
Published: October 2020

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Los intereses constitutivos del conocimiento: implicancias en el curriculum
Authors: Alderete Alicia Raquel
Published: October 2020

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APORTES DE LA ENSEÑANZA DE LA AUTOGESTIÓN A LA CONSTRUCCIÓN DE PROYECTOS DE VIDA DIFERENTES. UNA EXPERIENCIA CON MUJERES TRABAJADORAS DEL CONURBANO BONAERENSE
Authors: Miano María Amalia , Heras Ana Inés , Burin David
Published: October 2020

En este escrito analizamos una experiencia pedagógica que se desarrolló con mujeres en una localidad del conurbano bonaerense y que tuvo como objetivo enseñar a sus participantes algunos conceptos básicos acerca del cooperativismo de trabajo. Nos propusimos reflexionar sobre: 1) los aprendizajes incorporados por las mujeres en el proceso de la experiencia pedagógica en función de la historia de los grupos de trabajo que conforman y de las concepciones previas que tenían acerca del cooperativismo y, 2) los criterios y dispositivos que organizan la enseñanza a partir de analizar las interacciones que tuvieron lugar en la jornada de capacitación. Para esto nos preguntamos desde el enfoque etnográfico y la sociolingüística de la interacción ¿quién enseña que, a quien y con qué resultados identificables, al menos a corto plazo?
COGNICIÓN, PROTOFÍSICA Y LENGUAJE
Authors: Baldi Raúl Hugo , Contín Julia Eleonor
Published: October 2020

Conformamos en nuestra mente combos de improntas, paquetes de experiencias que esperamos ver aparecer de ese modo y en ciertas secuencias recurrentes. Disponemos de “recetas” –en las que anidan esos estigmas de mundo encarnados- para hacer predecible el acaecer natural, pero usamos otras para representarnos las intenciones de los seres vivos y actuar en consecuencia. Los caprichos pertenecen al universo psicológico. Nos sorprende que la realidad no se ajuste al “programa”. Por ello nos cuesta dar crédito a situaciones en las que vemos desagregados aquellos combos o alteradas sus secuencias.En este artículo describiremos algunos de esos condensados de experiencia. Mostraremos que ellos trascienden el ámbito del pensamiento donde estructuran nuestras ideas acerca del mundo y emergen en el lenguaje. Con metáforas como vectores se movilizan y aportan de ese modo soporte cognitivo para abarcar facetas más abstractas de nuestra realidad, desde la de nuestras volubles emociones hasta el esquivo concepto del tiempo.Hay una física vitalmente eficaz pero precaria a la hora de abandonar la estrechez de nuestra experiencia directa. Aportaremos evidencia acerca de que la tensión entre estas nociones espontáneas y las que pone sobre la palestra la Física constituye un obstáculo para el aprendizaje de los conceptos científicos. El lenguaje nos dará una clave para entrar en el reino de la protofísica y operar sobre él.
ADULTOS MAYORES Y EDUCACION INTERGENERACIONAL. EDUCACIÓN EN PERSONAS MAYORES
Authors: García Mínguez Jesús
Published: October 2020

La idea de educación a lo largo de la vida, por cierta y extendida, es un avance que abarca a todos los seres humanos independientemente de la edad. El presente trabajo invita a empujar los impulsos educativos hasta el colectivo de las personas mayores, como medio de capturar la continuidad de una vida cualificada personal y socialmente. Para sostener esta afirmación, el autor se adentra en el concepto de educación como derecho reconocido por la ONU en 1948; así mismo observa su evolución histórica hasta convertirse en un fenómeno generalmente asumido.
LA DESCENTRALIZACIÓN ANTES DE LA DESCENTRALIZACIÓN: POLÍTICAS EDUCATIVAS DURANTE EL GOBIERNO DE ONGANÍA
Authors: Southwel Myriam , De Luca Romina
Published: October 2020

Este artículo tiene el propósito de examinar las transformaciones del gobierno del sistema educativo durante la década de 1960. Tomaremos específicamente la etapa del gobierno dictatorial de Juan C. Onganía (1966-1970) y nos concentraremos en dos tendencias: por un lado, las medidas tendientes a la descentralización del sistema y –por otro- los cambios propuestos en el ámbito de la formación docente y como esas decisiones se enmarcaron en una nueva manera de concebir el trabajo docente y su articulación con la política y las funciones de la escuela. Para ello, analizaremos una institución clave para ambas corrientes: el Consejo Nacional de Desarrollo (CONADE).
LA EDUCACIÓN MEDIA PARA ADULTOS EN LA CÁRCEL. POSIBLES ADECUACIONES CURRICULARES
Authors: Pagnucco Viviana , Querol Claudio , Sartori Eleonora
Published: October 2020

Se intenta abordar la problemática curricular de la EEMPA dentro del contexto carcelario donde se produce un encuentro entre ámbitos relegados: educación para adultos –educación media-realidad carcelaria, que transita entre tensiones donde generalmente prevalece una institución sobre la otra.La educación carcelaria transcurre en situaciones signadas por exclusiones, estigmatizaciones y ‘excepción permanente’ en el respeto de los derechos humanos, incluido el de educación.Las escuelas carcelarias rosarinas fueron sostenidas fundamentalmente por el compromiso personal de docentes y directivos. La impronta vivencial que fue adquiriendo parece haber favorecido una relación teoría-práctica que tendería a postergar el valor de la reflexión teórica y su registro.Institucionalmente subyacen acuerdos tácitos que constituyeron la identidad de la escuela penitenciaria. Pero parece necesaria una teorización y explicitación que posibilite recrearla.Desde la práctica docente, se toma como punto de partida la caracterización de los grupos, pero las planificaciones no manifiestan adecuaciones atendiendo a la particularidad del contexto. Parecen no considerarlas como documentos que posibiliten la sistematicidad e intencionalidad pedagógicas.Es necesario repensar la representación social del cientista de la educación. se propone aquí una actitud de colaboración entre los actores educativos valorando aportes teórico-prácticos.
Educación de jóvenes y adultos, política social y gubernamentalidades en el siglo XXI
Authors: Langer Eduardo , Levy Esther
Published: October 2020

El abordaje de los aspectos políticos de la relación entre educación o formación y trabajo constituye un espacio privilegiado para la discusión de una amplia gama de aspectos y dimensiones que atraviesan el campo de esta problemática. En este artículo, analizamos dos experiencias educativas -los bachilleratos populares y contraprestaciones educativas en los planes sociales-, entendidos como dispositivos de injerencia de la regulación estatal. Ya sea por las características distintivas de los sujetos, como por la intensidad del sentido político, en ambos espacios el Estado regula y define las relaciones entre sujetos y educación. Si bien se trata de dos ámbitos que difieren por sus formatos y objetivos político-pedagógicos, creemos que en ambos el tipo de vinculación con el Estado define los modos de relación y las prácticas educativas que se generan. Por otro lado, las dos experiencias tienen en común que, además de estar relacionados con el derecho a la educación, también lo están con otro derecho: el derecho al trabajo. No obstante, en este punto existen diferencias sustantivas entre los objetivos explícitos de ambos espacios no sólo en términos de concepción sino de intencionalidad política.
Presentación
Authors: Ossanna Edgardo
Published: October 2020

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Consejos útiles de un estratega chino
Authors: Macera Irene Marina
Published: October 2020

En este texto nos proponemos introducir ciertas nociones del pensamiento chino para que colaboren, a modo de herramientas, en la interpretación y análisis de las relaciones de formación. El pensamiento chino será abordado desde la lectura y análisis que lleva a cabo un filósofo francés llamado Francois Jullien. Se trata de cómo las estrategias de guerra china sirven para pensar estrategias vitales contemporáneas. Siendo nuestro interés los procesos de formación, es que realizamos una aproximación entre estas prácticas y los modos de registro con los que nos podemos valer si tomamos en cuenta el pensamiento oriental.
Presentación
Authors: De Alba Alicia
Published: October 2020

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