bluuebunny/crossref_metadata_2025 huggingface dataset:
Quasi-Bragg plasmon modes for highly efficient plasmon-enhanced second-harmonic generation at near-ultraviolet frequencies
Authors: Shen Shaoxin , Zheng Jie , Lin Zhijian , Chen Ying , Gao Renxian , Jin Yu , Sun Guoya , Shih Tien-Mo , Yang Zhilin
Published: June 2021

Boosting nonlinear frequency conversions with plasmonic nanostructures at near-ultraviolet (UV) frequencies remains a great challenge in nano-optics. Here we experimentally design and fabricate a plasmon-enhanced second-harmonic generation (PESHG) platform suitable for near-UV frequencies by integrating aluminum materials with grating configurations involved in structural heterogeneity. The SHG emission on the proposed platform can be amplified by up to three orders of magnitude with respect to unpatterned systems. Furthermore, the mechanism governing this amplification is identified as the occurrence of quasi-Bragg plasmon modes near second-harmonic wavelengths, such that a well-defined coherent interplay can be attained within the hot spot region and facilitate the efficient out-coupling of local second-harmonic lights to the far-field. Our work sheds light into the understanding of the role of grating-coupled surface plasmon resonances played in PESHG processes, and should pave an avenue toward UV nanosource and nonlinear metasurface applications.
Large-mode-area multicore Yb-doped fiber for an efficient high power 976 nm laser
Authors: Li Huizi , Zang Jichao , Raghuraman Sidharthan , Chen Shaoxiang , Goel Charu , Xia Nan , Ishaaya Amiel , Yoo Seongwoo
Published: June 2021

We present an efficient 976 nm laser generation from an ytterbium (Yb)-doped step-index multicore fiber (MCF) with six cores placed in a ring shape. Each of the six cores has a large-mode-area (LMA) and a low numerical aperture (NA), which makes the MCF equipped with the features of a large core-to-cladding area ratio and differential bending loss for wavelength and mode selection. Hence, the Yb-doped MCF benefits 976 nm laser generation by simultaneously suppressing unwanted 1030 nm emission and higher-order modes (HOMs). A 976 nm laser is obtained in a short piece (88 cm) of the Yb MCF, with a good slope efficiency of 46% with respect to launched pump power and the maximum output power of 25 W (pump power limited). A mode area of 1432 µm2 at the 976 nm is expected for the fundamental in-phase mode.
Null-screen testing of the complementary freeform surfaces of an adjustable focus lens
Authors: Utrera Dulce Gonzalez , Aguirre-Aguirre Daniel , Rodríguez Rodríguez Martín I. , Uribe Rufino Diaz
Published: June 2021

A novel null-screen technique to test freeform optical surfaces for ophthalmic use is presented. We present an off-axis experimental setup to evaluate the surface shape of a two-element commercial adaptable focus lens based on the Alvarez principle. The advantages of the method are that it is fast, easy to implement, and reduces costs. This metrology technique is validated by testing both the convex and the concave complementary freeform elements of the spectacle under test. We also apply two methods to recover the surface shape of both elements: numerical integration and a custom probabilistic algorithm. Results are compared with a reference surface finding that for method 1, the RMS value in sagitta differences is 32.6 microns for the convex surface and 26.5 microns for the concave surface. Meanwhile, for method 2, the RMS value in sagitta differences found is 19.8 microns for the convex surface and 16.9 microns for the concave surface. Results show agreement in RMS in sagitta differences for both surfaces in each of the reconstruction methods employed.
Ultrashort pulsed laser backside ablation of fused silica
Authors: Schwarz Simon , Rung Stefan , Esen Cemal , Hellmann Ralf
Published: June 2021

We report on the fabrication of rectangular microchannels with vertical sidewalls in fused silica by laser backside ablation. A 515 nm femtosecond laser is focused by an objective with a NA of 0.5 through the sample on the glass/air interface, allowing processing from the backside into the bulk material. Experimental investigations reveal a logarithmically increasing depth of the channels with an increasing number of scans, while keeping the focal position fixed. A certain number of scans has to be applied to generate rectangular shaped channels while their depth can be controlled by the applied fluence from 2.64 µm to 13.46 µm and a corresponding ablation roughness R
a
between 0.20 µm and 0.33 µm. The channel width can be set directly via the number of parallel ablated lines demonstrated in a range from 10 µm to 50 µm. By adjusting the focal position after each scan the channel depth can be extended to 49.77 µm while maintaining a rectangular channel geometry. Finally, concentric rings are ablated to demonstrate the flexibility of the direct writing process.
Temperature-compensated optical fiber sensor for volatile organic compound gas detection based on cholesteric liquid crystal
Authors: Hu Jianyang , Chen Yuzhou , Ma Zhenyu , Zeng Li , Zhou Dong , Peng Zenghui , Sun Weimin , Liu Yongjun
Published: June 2021

External temperature variations inevitably affect the accuracy of a liquid crystal sensor. Therefore, we propose a novel temperature-compensated fiber volatile organic compound (VOC, using acetone as a model compound) gas sensor. The proposed sensor consists of a short segment of hollow-core fiber (HCF), which is spliced on a multimode fiber. Cholesteric liquid crystal (CLC) is sealed into HCF to sense the temperature, and another type of CLC is coated on the end face of HCF for VOC gas detection. The VOC gas concentration and ambient temperature can be simultaneously measured by monitoring the wavelength shifts of two Bragg reflection peaks caused by two types of CLCs. The effects of the CLC thickness on the sensitivities of temperature and acetone concentration are investigated, and optimal parameters are chosen. An optimal sensor can reach a temperature sensitivity of 2.53 nm/°C and acetone concentration sensitivity of 48.46 nm·L/mmol at 8–44°C. In addition, temperature compensation capability, repeatability, response time, and stability are also researched. The experimental results prove this sensor has great application potential in high-precision real-time VOC gas monitoring and detection.
Weak beam self-cleaning of femtosecond pulses in the anomalous dispersion regime
Authors: Wu Yuhang , Pourbeyram Hamed , Christodoulides Demetrios N. , Wise Frank W.
Published: June 2021

Kerr beam cleaning in graded-index multimode fiber has been investigated in experiments with sub-nanosecond pulses and in experiments with femtosecond pulses at wavelengths where the dispersion is normal. We report a theoretical and experimental study of this effect with femtosecond pulses and anomalous dispersion. In this regime, only weak beam cleaning is observed experimentally, along with strong temporal evolution of the pulse. Numerical simulations exhibit the qualitative trends of the experiments.
Nonlinear fiber system for shot-noise limited intensity noise suppression and amplification
Authors: Edelmann Marvin , Hua Yi , Şafak Kemal , Kärtner Franz X.
Published: June 2021

We propose a nonlinear fiber system for shot-noise limited, all-optical intensity noise reduction and signal amplification. The mechanism is based on the accumulation of different nonlinear phase shifts between orthogonal polarization modes in a polarization-maintaining fiber amplifier in combination with an implemented sinusoidal transmission function. The resulting correlation between the input intensity fluctuations and the system transmission enables tunable intensity noise reduction of the input pulse train. In the experiment, the noise spectral density of a mode-locked oscillator is suppressed by up to 20 dB to the theoretical shot-noise limit of the measurement at

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with simultaneous pulse amplification of 13.5 dB.
Immunohistochemical Comparative Study of Aggressive and Non-aggressive Central Giant Cell Lesions of the Jaws Based on the Tenascin-C Expression Profile
Authors: Tobón-Arroyave Sergio Iván , Isaza-Guzmán Diana María , Flórez-Moreno Gloria Amparo
Published: June 2021

The purpose of this study was to compare the immunohistochemical expression of tenascin-C (Tn-C) regarding clinicopathological variables and its association with the clinical behavior of central giant cell lesions (CGCLs). Forty-eight paraffin-embedded samples of CGCLs were selected. Based on clinical and radiographic features, the lesions were classified as aggressive (A-CGCLs) and non-aggressive (NA-CGCLs) subtypes. Histological assessment included the microvessel count (MVC), multinucleated giant cell (MGC) count, and the proportion of tissue area involved by mononuclear stromal cells/interstitial fibrosis. Immunoreactivity, immunolocalization, and distribution patterns of Tn-C were studied immunohistochemically. The association between Tn-C expression and clinicopathological characteristics was analyzed separately and adjusted for confounders using logistic regression models. A significantly greater proportion of cases with moderate-to-intense, intracellular, and diffuse staining of Tn-C was observed in A-CGCLs. CGCLs with a size ≥3.3 cm, fast growth, cortical disruption, high MVC/MGC counts, and low interstitial fibrosis showed a significantly greater frequency of moderate-to-intense, intracellular, and diffuse staining. Logistic regression analysis indicated a strong/independent association of these three immunohistochemical parameters with the aggressiveness of lesions. These data appear to suggest a possible role for Tn-C in the etiopathogenesis of CGCLs of the jaws, where its upregulation might favor the destructive behavior of A-CGCLs.
Iliski, a software for robust calculation of transfer functions
Authors: Aydin Ali-Kemal , Haselden William D. , Dang Julie , Drew Patrick J. , Charpak Serge , Boido Davide
Published: June 2021

Understanding the relationships between biological processes is paramount to unravel pathophysiological mechanisms. These relationships can be modeled with Transfer Functions (TFs), with no need of a priori hypotheses as to the shape of the transfer function. Here we present Iliski, a software dedicated to TFs computation between two signals. It includes different pre-treatment routines and TF computation processes: deconvolution, deterministic and non-deterministic optimization algorithms that are adapted to disparate datasets. We apply Iliski to data on neurovascular coupling, an ensemble of cellular mechanisms that link neuronal activity to local changes of blood flow, highlighting the software benefits and caveats in the computation and evaluation of TFs. We also propose a workflow that will help users to choose the best computation according to the dataset. Iliski is available under the open-source license CC BY 4.0 on GitHub (https://github.com/alike-aydin/Iliski) and can be used on the most common operating systems, either within the MATLAB environment, or as a standalone application.
Estimation of country-level incidence of early-onset invasive Group B Streptococcus disease in infants using Bayesian methods
Authors: Gonçalves Bronner P. , Procter Simon R. , Clifford Sam , Koukounari Artemis , Paul Proma , Lewin Alexandra , Jit Mark , Lawn Joy
Published: June 2021

Neonatal invasive disease caused by Group B Streptococcus (GBS) is responsible for much acute mortality and long-term morbidity. To guide development of better prevention strategies, including maternal vaccines that protect neonates against GBS, it is necessary to estimate the burden of this condition globally and in different regions. Here, we present a Bayesian model that estimates country-specific invasive GBS (iGBS) disease incidence in children aged 0 to 6 days. The model combines different types of epidemiological data, each of which has its own limitations: GBS colonization prevalence in pregnant women, risk of iGBS disease in children born to GBS-colonized mothers and direct estimates of iGBS disease incidence where available. In our analysis, we present country-specific maternal GBS colonization prevalence after adjustment for GBS detection assay used in epidemiological studies. We then integrate these results with other epidemiological data and estimate country-level incidence of iGBS disease including in countries with no studies that directly estimate incidence. We are able to simultaneously estimate two key epidemiological quantities: the country-specific incidence of early-onset iGBS disease, and the risk of iGBS disease in babies born to GBS-colonized women. Overall, we believe our method will contribute to a more comprehensive quantification of the global burden of this disease, inform cost-effectiveness assessments of potential maternal GBS vaccines and identify key areas where data are necessary.
How does feedback from phage infections influence the evolution of phase variation in Campylobacter?
Authors: Sandhu Simran K. , Bayliss Christopher D. , Morozov Andrew Yu.
Published: June 2021

Campylobacter jejuni (C. jejuni) causes gastroenteritis following the consumption of contaminated poultry meat, resulting in a large health and economic burden worldwide. Phage therapy is a promising technique for eradicating C. jejuni from poultry flocks and chicken carcasses. However, C. jejuni can resist infections by some phages through stochastic, phase-variable ON/OFF switching of the phage receptors mediated by simple sequence repeats (SSR). While selection strength and exposure time influence the evolution of SSR-mediated phase variation (PV), phages offer a more complex evolutionary environment as phage replication depends on having a permissive host organism. Here, we build and explore several continuous culture bacteria-phage computational models, each analysing different phase-variable scenarios calibrated to the experimental SSR rates of C. jejuni loci and replication parameters for the F336 phage. We simulate the evolution of PV rates via the adaptive dynamics framework for varying levels of selective pressures that act on the phage-resistant state. Our results indicate that growth reducing counter-selection on a single PV locus results in the stable maintenance of the phage, while compensatory selection between bacterial states affects the evolutionary stable mutation rates (i.e. very high and very low mutation rates are evolutionarily disadvantageous), whereas, in the absence of either selective pressure the evolution of PV rates results in mutation rates below the basal values. Contrastingly, a biologically-relevant model with two phase-variable loci resulted in phage extinction and locking of the bacteria into a phage-resistant state suggesting that another counter-selective pressure is required, instance, the use of a distinct phage whose receptor is an F336-phage-resistant state. We conclude that a delicate balance between counter-selection and phage-attack can result in both the evolution of phase-variable phage receptors and persistence of PV-receptor-specific phage.
Free energy landscape of RNA binding dynamics in start codon recognition by eukaryotic ribosomal pre-initiation complex
Authors: Kameda Takeru , Asano Katsura , Togashi Yuichi
Published: June 2021

Specific interaction between the start codon, 5’-AUG-3’, and the anticodon, 5’-CAU-3’, ensures accurate initiation of translation. Recent studies show that several near-cognate start codons (e.g. GUG and CUG) can play a role in initiating translation in eukaryotes. However, the mechanism allowing initiation through mismatched base-pairs at the ribosomal decoding site is still unclear at an atomic level. In this work, we propose an extended simulation-based method to evaluate free energy profiles, through computing the distance between each base-pair of the triplet interactions involved in recognition of start codons in eukaryotic translation pre-initiation complex. Our method provides not only the free energy penalty for mismatched start codons relative to the AUG start codon, but also the preferred pathways of transitions between bound and unbound states, which has not been described by previous studies. To verify the method, the binding dynamics of cognate (AUG) and near-cognate start codons (CUG and GUG) were simulated. Evaluated free energy profiles agree with experimentally observed changes in initiation frequencies from respective codons. This work proposes for the first time how a G:U mismatch at the first position of codon (GUG)-anticodon base-pairs destabilizes the accommodation in the initiating eukaryotic ribosome and how initiation at a CUG codon is nearly as strong as, or sometimes stronger than, that at a GUG codon. Our method is expected to be applied to study the affinity changes for various mismatched base-pairs.
Simulation of the cement measurement based on the pulse DT neutron generator: A Monte Carlo study
Authors: Gao Yadong , Li Jiaming , Li Jichen , Liu Linmao
Published: June 2021

The PGNAA system for the cement measurement was simulated based on Monte Carlo method. The sizes of the moderator and reflector for the 14 MeV DT neutron generator were optimized for fast and thermal neutron outputs. The DT neutron generator was simulated at the pulse mode, and the gamma-ray detector was set as LaBr3(Ce) scintillator. The characteristic peaks of the major elements (Ca, Si, Al, Fe) can be identified from the gamma-ray spectra which induced at the different time intervals of the neutron radiation. For the different thicknesses of the cement sample the ratios of the gamma-ray peaks were observed, and the result showed that when the thickness was between 20 to 30 cm, the ratios became stable. With the ratios, we can calculate the iron modulus, silica modulus and lime saturation factor.
Microfluidics sorting enables the isolation of an intact cellular pair complex of CD8+ T cells and antigen-presenting cells in a cognate antigen recognition-dependent manner
Authors: Kuwabara Soichiro , Tanimoto Yoshihiko , Okutani Mie , Jie Meng , Haseda Yasunari , Kinugasa-Katayama Yumi , Aoshi Taiki
Published: June 2021

Adaptive immune responses begin with cognate antigen presentation-dependent specific interaction between T cells and antigen-presenting cells. However, there have been limited reports on the isolation and analysis of these cellular complexes of T cell-antigen-presenting cell (T/APC). In this study, we successfully isolated intact antigen-specific cellular complexes of CD8+T/APC by utilizing a microfluidics cell sorter. Using ovalbumin (OVA) model antigen and OT-I-derived OVA-specific CD8+T cells, we analyzed the formation of antigen-specific and antigen-non-specific T/APC cellular complexes and revealed that the antigen-specific T/APC cellular complex was highly stable than the non-specific one, and that the intact antigen-specific T/APC complex can be retrieved as well as enriched using a microfluidics sorter, but not a conventional cell sorter. The single T/APC cellular complex obtained can be further analyzed for the sequences of T cell receptor Vα and Vβ genes as well as cognate antigen information simultaneously. These results suggested that this approach can be applied for other antigen and CD8+T cells of mice and possibly those of humans. We believe that this microfluidics sorting method of the T/APC complex will provide useful information for future T cell immunology research.
Awareness of COVID-19 influences on the wellness of Thai health professional students: An ambulatory assessment during the early “new normal” informing policy
Authors: Tiaprapong Krueakaew , Sirikul Achiraporn , Krajangmek Chamawee , Duangthongkul Namfon , Pandam Nichaya , Piya-amornphan Nitita
Published: June 2021

The COVID-19 global pandemic has had a socioeconomic effect, including many people suffering from stress and mental disorders. Health professional students are at risk of health issues as well when compared to their age-matched counterpart in the population. The present study aimed to find out the impact of COVID-19 awareness on the wellness of Thai health professional students. The awareness of COVID-19 and wellness among Thai health professional students, such as medical, physical therapy, nursing, pharmacy, and medical technology students were surveyed during the early “new normal” informing policy. The participants included 1,001 students, aged 17 to 25 years old, who responded to a Google form questionnaire set by request. The results showed that the prominent health risks among the Thai health professional students included sedentary behavior, obesity, and mental symptoms. A positive rating in attitude towards the COVID-19 epidemic was mostly observed. There was a negative influence on anxiety symptoms (standardized coefficient beta = -0.079, p-value = 0.012), but a positive impact on social well-being (standardized coefficient beta = 0.158, p-value < 0.001) and quality of life (standardized coefficient beta = 0.136, p-value < 0.001) among the students even when the situation was improving. To relieve the domino effect of the COVID-19 pandemic on students’ wellness, an updated policy for enhancing awareness and providing updated information is continuously required. Improvements on self and situational awareness may help prevent health risk behaviors and promote health among Thai health professional students.
Spatial inhibition of return is impaired in mild cognitive impairment and mild Alzheimer’s disease
Authors: Jiang Xiong , Howard James H. , Rebeck G. William , Turner Raymond Scott
Published: June 2021

Spatial inhibition of return (IOR) refers to the phenomenon by which individuals are slower to respond to stimuli appearing at a previously cued location compared to un-cued locations. Here with a group of older adults (n = 56, 58–80 (67.9±5.2) year old, 31 females, 18.7±3.6 years of education), we provide evidence supporting the notion that spatial IOR is mildly impaired in individuals with mild cognitive impairment (MCI) or mild Alzheimer’s disease (AD), and the impairment is detectable using a double cue paradigm. Furthermore, reduced spatial IOR in high-risk healthy older individuals is associated with reduced memory and other neurocognitive task performance, suggesting that the double cue spatial IOR paradigm may be useful in detecting MCI and early AD.
Evaluation of Computer-Aided Nodule Assessment and Risk Yield (CANARY) in Korean patients for prediction of invasiveness of ground-glass opacity nodule
Authors: Lee Juyoung , Bartholmai Brian , Peikert Tobias , Chun Jaehee , Kim Hojin , Kim Jin Sung , Park Seong Yong
Published: June 2021

Differentiating the invasiveness of ground-glass nodules (GGN) is clinically important, and several institutions have attempted to develop their own solutions by using computed tomography images. The purpose of this study is to evaluate Computer-Aided Analysis of Risk Yield (CANARY), a validated virtual biopsy and risk-stratification machine-learning tool for lung adenocarcinomas, in a Korean patient population. To this end, a total of 380 GGNs from 360 patients who underwent pulmonary resection in a single institution were reviewed. Based on the Score Indicative of Lung Cancer Aggression (SILA), a quantitative indicator of CANARY analysis results, all of the GGNs were classified as “indolent” (atypical adenomatous hyperplasia, adenocarcinomas in situ, or minimally invasive adenocarcinoma) or “invasive” (invasive adenocarcinoma) and compared with the pathology reports. By considering the possibility of uneven class distribution, statistical analysis was performed on the 1) entire cohort and 2) randomly extracted six sets of class-balanced samples. For each trial, the optimal cutoff SILA was obtained from the receiver operating characteristic curve. The classification results were evaluated using several binary classification metrics. Of a total of 380 GGNs, the mean SILA for 65 (17.1%) indolent and 315 (82.9%) invasive lesions were 0.195±0.124 and 0.391±0.208 (p < 0.0001). The area under the curve (AUC) of each trial was 0.814 and 0.809, with an optimal threshold SILA of 0.229 for both. The macro F1-score and geometric mean were found to be 0.675 and 0.745 for the entire cohort, while both scored 0.741 in the class-equalized dataset. From these results, CANARY could be confirmed acceptable in classifying GGN for Korean patients after the cutoff SILA was calibrated. We found that adjusting the cutoff SILA is needed to use CANARY in other countries or races, and geometric mean could be more objective than F1-score or AUC in the binary classification of imbalanced data.
Semi-analytical modelling and evaluation of uniformly doped silicene nanotransistors for digital logic gates
Authors: Chuan Mu Wen , Wong Kien Liong , Riyadi Munawar Agus , Hamzah Afiq , Rusli Shahrizal , Alias Nurul Ezaila , Lim Cheng Siong , Tan Michael Loong Peng
Published: June 2021

Silicene has attracted remarkable attention in the semiconductor research community due to its silicon (Si) nature. It is predicted as one of the most promising candidates for the next generation nanoelectronic devices. In this paper, an efficient non-iterative technique is employed to create the SPICE models for p-type and n-type uniformly doped silicene field-effect transistors (FETs). The current-voltage characteristics show that the proposed silicene FET models exhibit high on-to-off current ratio under ballistic transport. In order to obtain practical digital logic timing diagrams, a parasitic load capacitance, which is dependent on the interconnect length, is attached at the output terminal of the logic circuits. Furthermore, the key circuit performance metrics, including the propagation delay, average power, power-delay product and energy-delay product of the proposed silicene-based logic gates are extracted and benchmarked with published results. The effects of the interconnect length to the propagation delay and average power are also investigated. The results of this work further envisage the uniformly doped silicene as a promising candidate for future nanoelectronic applications.
Cambios generados por la COVID-19 en la práctica formativa e investigativa en Trabajo Social: oportunidades, dilemas y retos para la investigación social
Authors: Mejía Ospina Paola Ximena , Velásquez López Paula Andrea
Published: June 2021

Introducción. Este artículo presenta los resultados de una investigación que tuvo como objetivo analizar las condiciones que docentes y estudiantes de Trabajo Social tuvieron para realizar investigaciones científicas o trabajos de fin de carrera durante la crisis de la COVID-19.  Se asumió la perspectiva comprensivista de las ciencias sociales, desde autores que debaten la racionalidad técnico-instrumental y que plantean, en contraposición, la necesidad de una racionalidad práctico-reflexiva tanto en la práctica profesional como en la formación en Trabajo Social. Los autores llamados a dialogar proceden de la Filosofía, la Sociología y el Trabajo Social, con posturas frente los conceptos de “saber práctico”, “proceso reflexivo”, “reflexividad” y “conocimiento en la acción”. Metodología. El diseño metodológico se sustentó en una lectura emic de la realidad. Se utilizó una muestra aleatoria simple por conveniencia, a partir de criterios muestrales como: ubicación geográfica, cargo ocupado en las universidades y experiencia en investigación. Como técnicas se utilizaron la revisión documental, para el análisis de 42 proyectos de tesis, y la entrevista semiestructurada a siete (7) académicos-investigadores —de cuatro (4) países de América Latina— y a once (11) estudiantes que cumplían con: encontrarse en el semestre de fin de carrera, pertenecer a una universidad de la ciudad de Guayaquil y estar investigando temas relacionados con la pandemia. Resultados. Teniendo en cuenta cuatro dimensiones: el contexto, la práctica investigativa y la producción científica de docentes, la tutoría de la producción académica de los estudiantes de fin de carrera y la formación investigativa en Trabajo Social, se hicieron evidentes las alteraciones en las voces de lo que implicó la pandemia en la cotidianidad para quienes estaban realizando algún proyecto de investigación o formando nuevos investigadores. Las dinámicas personales producto del virus han redireccionado y, sobre todo, producido aprendizajes que nutren la posibilidad de describir, explicar y comprender nuevas dinámicas para formar y producir conocimiento. Discusión y conclusiones. Se plantean nuevos retos o dilemas para la investigación en Trabajo Social, en tanto que la pandemia —como hecho sociohistórico y bio-psico-social— evidenció que las desigualdades y las vulnerabilidades sociales no necesariamente están solo en el plano de la materialidad física o de tener los recursos tecnológicos a disposición (un computador, un celular, internet, servicio de energía); esto, si acaso, modificará los presupuestos en las investigaciones para dotar de estas materialidades a las personas  vinculadas. Además, existen en otro plano: el subjetivo, en el cual la cultura, el territorio, la clase o el género, entre otros, determinan vulneraciones más complejas que en el mundo simbólico al que pertenecen y no es posible resolverlas con una simple inversión material o tecnológica.
Ecological Significance of Residues Retention for Sustainability of Agriculture in the Semi-arid Tropics
Authors: Gupta Raj , Benbi DK , Abrol IP
Published: June 2021

In South Asia, land degradation is primarily a monsoon mediated phenomenon restricted to 2-3 rainy months. The overall strategy for land degradation neutrality should (i) favour actions that keep soils covered with residues and (ii) plant kharif (rainy season) crop before the onset of monsoons to provide soil cover. Retention of anchored residues provides surface cover, increases microbial activity, carbon sequestration, and availability of nutrients. Surface retained residues reduce root zone salinization, detoxify phytotoxic monomeric Al in acidic soils and enhance the potential for use of brackish ground water in crop production. Residues covers save irrigation water and overcome the ill effects of poor agronomic and water management practices. Early direct dry seeding in surface retained residues has the potential of making kharif season planting independent of the onset of monsoon rains in South Asia and helps reduce acreages of Kharif and Rabi fallow lands. For improving carbon content in Indian soils, perhaps the most important priority is to devise tillage and crop residue management approaches that promote in situ rain water storage and its use for growing more crops. The paper summarises how crop residues fuel and drive soil functions and related ecosystem services and plant growth.
Sediment input from the São Francisco River bank, Northeast Brazil, under low discharge period
Authors: Holanda Francisco Sandro Rodrigues , Santos Maria Hosana dos , Jesus Janisson Batista de , Santos Wadson De Menezes , Sena Edinaldo De Oliveira Alves , Chagas Thiago Xavier , Goes João Horácio Dantas Almeida de , Santos Luiz Diego Vidal
Published: June 2021

The objective of this study was to evaluate the input of suspended sediment from the slope toe in the São Francisco River channel, in Northeast Brazil, under different soil bioengineering techniques. Sediments were collected in the years of 2013, 2014 and 2015, in five transects crossing the river channel. Sediment input in the sampling points was higher in the year of 2013, i.e., the year of the highest river discharge. Sediment supply to the river channel for a period of 3 years (2013, 2014 and 2015), was evaluated at 20, 40 and 60% depth, along five different transects (P1= riverbank, P2= beginning of the thalweg, P3= middle of the thalweg, P4= end of the thalweg, and P5 = margin of the side sandybar), oriented by the presence or absence of erosion control techniques (treatments) such as: 1-Natural Vegetated Slope; 2-Vegetated Riprap; 3-Eroded Slope; 4-Live Cribwall and 5-Vetiver grass Contour Line. Sediments input was different in all evaluated transects, and the one identified as Eroded Slope at 20% depth presented the lowest amount of suspended sediment load. There was a decrease in the total amount of suspended sediment in the evaluated periods, probably due to the progressive decrease in the river discharge, and the protection provided by the soil bioengineering techniques.
Unidades morfotectónicas-volcánicas del sector noroeste del volcán Poás, Costa Rica
Authors: Arroyo-Solórzano Mario , Quesada-Román Adolfo , Vargas-Bolaños Christian
Published: June 2021

La dinámica tectónica y volcánica de Costa Rica responde principalmente a la interacción de las placas del Coco y Caribe. Con base en la relación entre las estructuras geológicas, rangos altitudinales, parámetros morfométricos y formas de relieve, se definieron diez unidades morfotectónicas-volcánicas (UMTV) que caracterizan el relieve resultante de la evolución del edificio volcánico del Volcán Poás en su sector Noroeste. Se elaboró un mapa considerando criterios asociados a elementos y atributos morfotectónicos y morfoestructurales, litoestratigráficos, geomorfológicos y morfométricos. Basados en estudios previos de la zona, así como con la utilización de sensores remotos como tecnología Lidar, imágenes de Radar y fotografías aéreas, se combinaron criterios que incluyeron la identificación e interpretación de estructuras tectónicas o volcánicas, el rango altitudinal, la geología y el origen de las formas de relieve, la pendiente, la sismicidad, lineamientos y la interpretación de patrones de la red hidrográfica. Las UMTV identificadas integran las diferentes estructuras y la geología de la zona, y reconocen la importancia de la actividad neotectónica en la formación y diferenciación del relieve. Las UMTV constituyen un insumo inicial para la evaluación de amenazas naturales, siendo una herramienta funcional en el Ordenamiento Territorial y la Gestión del Riesgo, con gran potencial de replicación en sitios con características similares a la zona de estudio, en ambientes volcánicos y climas tropicales.
Acaricidal activity of Furcraea foetida leaf extract against engorged female Rhipicephalus (Boophilus) microplus ticks
Authors: Martins Henrique Aparecido de Sousa , Pereira Maria de Fatima , Konzen Enéas Ricardo , Brondani Gilvano Ebling , Campos Wellington Ferreira
Published: June 2021

The Rhipicephalus (Boophilus) microplus tick is a major concern for the livestock market worldwide, as it causes serious economic damage. Plant-derived acaricides are an attractive alternative to control this ectoparasite and limit the development of resistance. Therefore, the aim of this study was to evaluate the acaricidal activity of Furcraea foetida leaf extract against engorged female R. (B.) microplus ticks. Our in vitro bioassays showed that the crude extract of leaves from F. foetida caused hemorrhagic swelling and skin lesions in the ticks, and three days of treatment caused 100% mortality. Dose-response assay indicated that this toxicity effect was dose-dependent. Similar effects were observed when the crude extract from F. foetida leaves was denatured by boiling at 100°C. These results suggest that the toxicity of the leaf extract might be associated with thermostable biomolecules. Together, our results show for the first time that the crude extract of F. foetida leaves has acaricidal activity against engorged female R. (B.) microplus ticks and it acts in a dose-dependent manner.
Adolescentes em vulnerabilidade social
Authors: Dourado Júnior Francisco Wellington , Alcântara Jussara Alves , Silva Kellyanne  Abreu , Mendes Paula Rivele Gomes Sousa
Published: June 2021

O estudo tem como objetivo relatar a experiência de implementação de uma ação educativa sobre Projeto de Vida, com um grupo de adolescentes em condição de vulnerabilidade social aplicando o Círculo de Cultura de Paulo Freire. Trata-se de um relato de experiência de uma ação educativa fundamentada nesse método, contando com a participação de adolescentes inseridos em um contexto de vulnerabilidade social, cuja realização dispôs de duas etapas: diagnóstico situacional e implementação do círculo de cultura. A ação foi realizada durante os meses de abril e maio de 2019, no Centro de Referência de Assistência Social, em um grupo formado por 20 participantes. O referencial teórico adotado possibilitou a formação de um espaço de compartilhamento de conhecimentos, ideias, pensamentos e visões, favorecendo uma problematização crítica acerca das temáticas identificadas pelo grupo como definidoras do universo da adolescência, além de ser uma estratégia de transformação de realidades comunitárias. Portanto, a experiência possibilitou aos adolescentes o conhecimento e o desenvolvimento de um papel protagonista na transformação individual e coletiva, bem como um novo enfrentamento do contexto de vulnerabilidades que os cercam.
Construção do acolhimento com classificação de risco em uma Unidade Básica de Saúde
Authors: Portela Tainá de Jesus Alves , Farias Quiteria Larissa Teodoro , Vasconcelos Maristela Inês Osawa
Published: June 2021

O estudo tem como objetivo descrever a experiência de acadêmicos de enfermagem no desenvolvimento do Acolhimento com Classificação de Risco para profissionais e usuários de uma Unidade Básica de Saúde. Trata-se de um relato de experiência que traz a ação desenvolvida por acadêmicos do 8º semestre do Módulo de Internato 1 do Curso de Graduação em Enfermagem da Universidade Estadual Vale do Acaraú na implantação do Acolhimento com Classificação de Risco em uma Unidade Básica de Saúde da região noroeste do estado do Ceará. As ações foram estruturadas em 6 encontros onde 2 envolveram os profissionais da equipe de enfermagem, 1 englobou todos os trabalhadores da unidade básica e 3 abordaram os usuários do serviço onde a partir de temáticas e materiais estudados anteriormente possibilitaram a construção de dispositivos facilitadores do aprendizado dos participantes. Os resultados desse estudo são apresentados e discutidos em dois tópicos essenciais para a elaboração das metodologias: organização do trabalho e transformação das práticas profissionais; e potencialização no atendimento da/para população. As estratégias de educação permanente com os profissionais da unidade e educação em saúde com os usuários adotadas na experiência constituíram-se como potencializadoras na transformação das práticas do trabalho.
Formação continuada de professores da educação básica no campo
Authors: Silva Elizeni Belo da , Medeiros Emerson Augusto de
Published: June 2021

Este estudo tematiza a formação continuada de professores da Educação Básica do Campo. Objetiva compreender como se desenvolve a formação continuada de docentes dos anos iniciais do Ensino Fundamental de uma escola municipal, Assentamento Favela, Mossoró-RN. Em parâmetros metodológicos, ancora-se na abordagem qualitativa e se caracteriza como uma investigação de cunho exploratório e descritivo. Participaram do estudo duas professoras que lecionam em turmas multisseriadas dos anos iniciais do Ensino Fundamental situadas na escola em referência. Como técnica para a construção dos dados, utilizou-se questionário composto por dez questões abertas. Conclui-se, entre outros pontos, que as práticas de formação continuada vivenciadas pelas participantes da pesquisa não se alinham, em maior parte, à Educação do Campo, situada no texto como um movimento nacional de educação. No entanto, contribuem em parte para a qualificação do trabalho docente desenvolvido pelas professoras em sala de aula.
Ni–Ru-containing mixed oxide-based composites as precursors for ethanol steam reforming catalysts: Effect of the synthesis methods on the structural and catalytic properties
Authors: Naurzkulova Symbat Muratbekovna , Arapova Marina Vasilievna , Ishchenko Arcady Vladimirovich , Krieger Tamara Andreevna , Saraev Andrei Aleksandrovich , Kaichev Vasilii Vasilievich , Rogov Vladimir Alekseevich , Krasnov Aleksei Vyacheslavovich , Massalimova Bakytgul Kabykenovna , Sadykov Vladislav Aleksandrovich
Published: June 2021

Ethanol steam reforming catalyst’s precursors, i.e., nanocomposites of complex oxides with the general formula [Pr0.15Sm0.15Ce0.35Zr0.35O2 + LaMn0.45Ni0.45Ru0.1O3] (1:1 by mass), were synthesized by three different methods. It was shown that two synthesis methods – ultrasonic dispersion and sequential polymeric method, lead to the formation of the nanocomposite perovskite–fluorite system with the specific surface area up to 50 m2/g. Reduction of samples at 400–500°C lead to the formation of Ni–Ru alloy nanoparticles strongly bound with the surface of oxide nanocomposite. Catalytic tests in ethanol steam reforming reaction at 500–600°C showed the highest specific activity of the sample prepared by the sequential polymeric method due to the location of Ni- and Ru-containing perovskite mainly on the surface of the composite providing a high concentration of active metal centers. At higher temperatures for all samples, ethanol conversion approached 100% with hydrogen yield varying in the range of 65–75%. A study of spent catalysts confirmed the absence of carbon deposits after long-term catalytic tests at 650°C.
„Familien-Denkmal“ vs. „National Eigenthum“
Authors: Höppner Stefan
Published: June 2021

Johann Wolfgang von Goethe’s personal library was a prime source of his literary and scientific writings, but has nonetheless found little attention in research. This study explains this disregard by examining the library as both “familial inheritance” (Erbe) and “cultural heritage” (Kulturerbe), two conflicting concepts that, nonetheless, both resulted in the monumentalization of the writer’s book collection. By turning Goethe’s library into a monument, the individual, telling histories of the books he owned, has often been overshadowed. Many books are associated with multiple owners and have gone through the hands of Goethe’s family, friends, and assistants. Against this background, provenance research allows us to gain new insights into Goethe’s works, reading and writing practices, as well as his stylization as a German national poet.
Injecting Fairness into COVID-19 Vaccine Injury Compensation: No-Fault Solutions
Authors: Watts Kim , Popa Tina
Published: June 2021

The devastating impact of the COVID-19 global pandemic has fast-tracked the development of vaccines against the SARS-CoV-2 virus, with global vaccination efforts already underway. While the introduction of large-scale or even mandatory vaccination will facilitate resumed social interaction, work and travel, such action is not without risks. Vaccination exposes recipients to the risk of rare but serious effects, leading to pertinent questions about liability and compensation for harm caused by vaccination. There have already been rare blood clotting reactions associated with two COVID-19 vaccines, some of which have been fatal. Traditional means of accessing compensation, such as liability-based litigation, product liability regimes and existing statutory schemes may be inadequate avenues of accessing compensation for individuals who sustain vaccine-related harm. Despite a significant number of countries worldwide introducing vaccine injury compensation schemes, many European countries and Australia have been hesitant to develop a no-fault scheme to respond to potential vaccine-related injuries. This article critically analyses whether existing compensation mechanisms, including liability-based tort claims, operating in common law and civil jurisdictions, are adequate avenues of accessing compensation by injured individuals. Australia and Europe are compared because of the close similarities in their existing liability-exemption approach to vaccine injury compensation, rather than no-fault. This stands in stark contrast to the use of no-fault schemes in other major jurisdictions, and the COVAX vaccine injury compensation scheme available in 92 low- and medium-income countries. The authors conclude that the introduction of a no-fault vaccine injury compensation scheme is a desirable mechanism to compensate vaccine-related injuries, by offering a more efficient and easily accessible method of accessing compensation when compared with liability-based causes of action. With the commencement of vaccination, urgent introduction of no-fault vaccination injury compensation schemes ought to be at the forefront of lawmakers’ reform agenda.
A rangewide distribution model for the Pallas’s cat (Otocolobus manul): identifying potential new survey regions for an understudied small cat
Authors: Greenspan Evan , Giordano Anthony J.
Published: June 2021

Knowledge about the current distribution of threatened and/or understudied species is a fundamental component of conservation biology. Mapping species distributions based on recent known occurrences is particularly important for those that are rare or declining. Too often, cryptic species go undetected throughout parts of their range, whereas others just receive less research attention. We used contemporary presence data for the Pallas’s cat (Otocolobus manul), a small cryptic felid, to characterize potential rangewide and regional habitat for the species and identify those abiotic and biotic variables most influencing its distribution. Several regions lacking contemporary occurrence records contain potential habitat for Pallas’s cats, including the Koh-i-Baba Mountains of Afghanistan, Qinghai-Tibetan Plateau, steppes of Inner Mongolia, Kunlun Mountains of China, and Tian Shan and Pamir Mountains of Kyrgyzstan, Tajikistan, and China. Some of these areas have not been included in prior rangewide distribution assessments. The distribution of pikas (Ochotonaspp.), small mammals that likely represent a critical prey species everywhere they are sympatric, was the most important factor affecting the Pallas’s cat’s distribution. This suggests Pallas’s cats may be prey specialists, and that pika presence and habitat are critical considerations for future Pallas’s cat surveys and in the development of regional conservation actions.
The Enemy Next Door: The Image of Russia in Georgian and Ukrainian Political Discourses Amid Conflicts Escalation
Authors: Terzyan Aram
Published: June 2021

This article presents an analysis of the evolution of Russia’s image representation in Georgian and Ukrainian political discourses amid Russian-Georgian and Russian-Ukrainian conflicts escalation. Even though Georgia’s and Ukraine’s troubled relations with neighboring Russia have been extensively studied, there has been little attention to the ideational dimensions of the confrontations, manifested in elite narratives, that would redraw the discursive boundaries between “Us” and “Them.” This study represents an attempt to fill the void, by examining the core narratives of the enemy, along with the discursive strategies of its othering in Georgian and Ukrainian presidential discourses through critical discourse analysis. The findings suggest that the image of the enemy has become a part of “New Georgia’s” and “New Ukraine’s” identity construction - inherently linked to the two countries’ “choice for Europe.” Russia has been largely framed as Europe’s other, with its “inherently imperial,” “irremediably aggressive” nature and adherence to illiberal, non-democratic values. The axiological and moral evaluations have been accompanied by the claims that the most effective way of standing up to the enemy’s aggression is the “consolidation of democratic nations,” coming down to the two countries’ quests for EU and NATO membership.