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Feedstock characteristics impact biochar physicochemical properties, and reproducible biochar properties are essential for any potential application. However, in most articles, feedstock aspects (i.e., taxonomic name of the species, part of the plant, and phenological phase) are scarcely reported. This research aimed at studying the effect of species and phenological stage of the feedstock on the properties of the derived biochars and, thus, adsorption capacities in water treatment. In this study, we analysed the anatomical characteristics of three different woody bamboo species [Guadua chacoensis (GC), Phyllostachys aurea (PA), and Bambusa tuldoides (BT)] in culms harvested at two different phenological phases (young and mature), and statistically correlated them with the characteristics of the six derived biochars, including their adsorption performance in aqueous media. Sclerenchyma fibres and parenchyma cells diameter and cell-wall width significantly differed among species. Additionally, sclerenchyma fibres and parenchyma cell-wall width as well as sclerenchyma fibre cell diameters are dependent on the phenological phase of the culms. Consequently, differences in biochar characteristics (i.e., yield and average pore diameter) were also observed, leading to differential methylene blue (MB) adsorption capacities between individuals at different phenological phases. MB adsorption capacities were higher for biochar produced from young culms compared to those obtained from matures ones (i.e., GC: 628.66 vs. 507.79; BT: 537.45 vs. 477.53; PA: 477.52 vs. 462.82 mg/g), which had smaller cell wall widths leading to a lower percentage of biochar yield. The feedstock anatomical properties determined biochar characteristics which modulated adsorption capacities.

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Research on the use of biomass resources for the generation of energy and chemical compounds is of great interest worldwide. The development and growth of the biodiesel industry has led to a parallel market for the supply of glycerol, its main by-product. Its wide availability and relatively low cost as a raw material make glycerol a basic component for obtaining various chemical products and allows for the development of a biorefinery around biodiesel plants, through the technological integration of different production processes. This work proposes a review of one of the reactions of interest in the biorefinery environment: the hydrogenolysis of glycerol to 1,2-propylene glycol. The article reviews more than 300 references, covering literature from about 20 years, focusing on the heterogeneous catalysts used for the production of glycol. In this sense, from about 175 catalysts, between bulk and supported ones, were revised and discussed critically, based on noble metals, such as Ru, Pt, Pd, and non-noble metals as Cu, Ni, Co, both in liquid (2-10 MPa, 120-260 °C) and vapor phase (0.1 MPa, 200-300 °C). Then, the effect of the main operational and decision variables, such as temperature, pressure, catalyst/glycerol mass ratio, space velocity, and H2 flow, are discussed, depending on the reactors employed. Finally, the formulation of several kinetic models and stability studies are presented, discussing the main deactivation mechanisms of the catalytic systems such as coking, leaching, and sintering, and the presence of impurities in the glycerol feed. It is expected that this work will serve as a tool for the development of more efficient catalytic materials and processes towards the future projection of glycerol biorefineries.

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Several families of transcription factors (TFs) control the progression of senescence. Many key TFs belonging to the WRKY family have been described to play crucial roles in the regulation of leaf senescence, mainly in Arabidopsis thaliana. However, little is known about senescence-associated WRKY members in floricultural species. Delay of senescence in leaves and petals of Petunia hybrida, a worldwide ornamental crop are highly appreciated traits. In this work, starting from 28 differentially expressed WRKY genes of A. thaliana during the progression of leaf senescence, we identified the orthologous in P. hybrida and explored the expression profiles of 20 PhWRKY genes during the progression of natural (age-related) leaf and corolla senescence as well as in the corollas of flowers undergoing pollination-induced senescence. Simultaneous visualization showed consistent and similar expression profiles of PhWRKYs during natural leaf and corolla senescence, although weak expression changes were observed during pollination-induced senescence. Comparable expression trends between PhWRKYs and the corresponding genes of A. thaliana were observed during leaf senescence, although more divergence was found in petals of pollinated petunia flowers. Integration of expression data with phylogenetics, conserved motif and cis-regulatory element analyses were used to establish a list of candidates that could regulate more than one senescence process. Our results suggest that several members of the WRKY family of TFs are tightly linked to the regulation of senescence in P. hybrida. Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-022-01243-y.

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MOTIVATION: After the outstanding breakthrough of AlphaFold in predicting protein 3D models, new questions appeared and remain unanswered. The ensemble nature of proteins, for example, challenges the structural prediction methods because the models should represent a set of conformers instead of single structures. The evolutionary and structural features captured by effective deep learning techniques may unveil the information to generate several diverse conformations from a single sequence. Here, we address the performance of AlphaFold2 predictions obtained through ColabFold under this ensemble paradigm. RESULTS: Using a curated collection of apo-holo pairs of conformers, we found that AlphaFold2 predicts the holo form of a protein in ∼70% of the cases, being unable to reproduce the observed conformational diversity with the same error for both conformers. More importantly, we found that AlphaFold2's performance worsens with the increasing conformational diversity of the studied protein. This impairment is related to the heterogeneity in the degree of conformational diversity found between different members of the homologous family of the protein under study. Finally, we found that main-chain flexibility associated with apo-holo pairs of conformers negatively correlates with the predicted local model quality score plDDT, indicating that plDDT values in a single 3D model could be used to infer local conformational changes linked to ligand binding transitions. AVAILABILITY AND IMPLEMENTATION: Data and code used in this manuscript are publicly available at https://gitlab.com/sbgunq/publications/af2confdiv-oct2021. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

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BACKGROUND: Discrimination, abuse, and mistreatment are prevailing problems reported in neurosurgical training programs globally. Moreover, the current coronavirus disease 2019 (COVID-19) pandemic may also show a negative impact on burnout levels in neurosurgery residents. This study aims to evaluate burnout, discrimination, and mistreatment in neurosurgical residents training in Latin America during the severe acute respiratory syndrome coronavirus 2 era. METHODS: A 33-item electronic survey was sent to neurosurgery residents from Latin America from May 10 to 25, 2021. Statistical analysis was performed using SPSS version 25. RESULTS: A total of 111 neurosurgery residents responded to the survey. Mean age was 29.39 ± 2.37 years; 22.5% were female and 36% were training in Mexico. Residents who reported experiencing discrimination for testing positive to COVID-19 had the highest levels of depersonalization (66.7%; P = 0.043) and emotional exhaustion (75%; P = 0.023). Female respondents reported higher rates of gender discrimination (80% vs. 1.2%; P = 0.001), abuse (84% vs. 58.1%; P < 0.005), and sexual harassment (24% vs. 0%; P < 0.001) than did male respondents. Residents training in Mexico reported lower rates of emotional or verbal abuse (59.2% vs. 32.5%; P = 0.007) and bullying (P < 0.005) than did those in other countries in Latin America. Older age was a protective factor for high depersonalization scores (odds ratio [OR], 0.133; 95% confidence interval [CI], 0.035-0.500). Experiencing discrimination represented a risk factor for presenting high emotional exhaustion scores (OR, 3.019; 95% CI, 1.057-8.629). High levels of depersonalization were associated with a 7-fold increased risk of suicidal ideation (OR, 7.869; 95% CI, 1.266-48.88). CONCLUSIONS: The COVID-19 pandemic has been a significant burden on several aspects of health care workers' lives. Our results provide a broad overview of its impact on burnout, discrimination, and mistreatment as experienced by neurosurgery residents training in Latin America, laying the groundwork for future studies and potential interventions.

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Genomic selection based on the single-step genomic best linear unbiased prediction (ssGBLUP) approach is becoming an important tool in forest tree breeding. The quality of the variance components and the predictive ability of the estimated breeding values (GEBV) depends on how well marker-based genomic relationships describe the actual genetic relationships at unobserved causal loci. We investigated the performance of GEBV obtained when fitting models with genomic covariance matrices based on two identity-by-descent (IBD) and two identity-by-state (IBS) relationship measures. Multiple-trait multiple-site ssGBLUP models were fitted to diameter and stem straightness in five open-pollinated progeny trials of Eucalyptus dunnii, genotyped using the EUChip60K. We also fitted the conventional ABLUP model with a pedigree-based covariance matrix. Estimated relationships from the IBD estimators displayed consistently lower standard deviations than those from the IBS approaches. Although ssGBLUP based in IBS estimators resulted in higher trait-site heritabilities, the gain in accuracy of the relationships using IBD estimators has resulted in higher predictive ability and lower bias of GEBV, especially for low-heritability trait-site. ssGBLUP based on IBS and IBD approaches performed considerably better than the traditional ABLUP. In summary, our results advocate the use of the ssGBLUP approach jointly with the IBD relationship matrix in open-pollinated forest tree evaluation.

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BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has exerted a significant impact on health care workers. Recent studies have reported the detrimental effects of the pandemic on neurosurgery residents in North America, Asia, and Italy. However, the impact of the pandemic on neurosurgical training in Latin America and Spain has not yet been reported. In the present report, we describe effects of COVID-19 on training and working conditions of neurosurgery residents in these countries. METHODS: An electronic survey with 33 questions was sent to neurosurgery residents between September 7, 2020 and October 7, 2020. Statistical analysis was made in SPSS version 25. RESULTS: A total of 293 neurosurgery residents responded. The median age was 29.47 ± 2.6 years, and 79% (n = 231) were male. Of respondents, 36.5% (n = 107) were residents training from Mexico; 42% surveyed reported COVID symptoms and 2 (0.7%) received intensive care unit care; 61.4% of residents had been tested for COVID and 21.5% had a positive result; 84% of the respondents mentioned persisted with the same workload (≥70 hours per week) during the pandemic. Most residents from Mexico were assigned to management of patients with COVID compared with the rest of the countries (88% vs. 68.3%; P < 0.001), mainly in medical care (65.4% vs. 40.9%; P < 0.001), mechanical ventilators (16.8% vs. 5.9%; P = 0.003), and neurologic surgeries (94% vs. 83%; P = 0.006). CONCLUSIONS: Our results offer a first glimpse of the changes imposed by the COVID-19 pandemic on neurosurgical work and training in Latin America and Spain, where health systems rely strongly on a resident workforce.

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BACKGROUND: Recent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic represents an important negative impact on global training of neurosurgery residents. Even before the pandemic, discrimination is a challenge that neurosurgical residents have consistently faced. In the present study, we evaluated discriminatory conditions experienced by residents during their neurosurgical training in Mexico before the SARS-CoV-2 pandemic. METHODS: An electronic survey of 18 questions was sent among residents registered in the Mexican Society of Neurological Surgery (MSNS), between October 2019 and July 2020. Statistical analysis was made in IBM SPSS Statistics 25. The survey focused on demographic characteristics, discrimination, personal satisfaction, and expectations of residents. RESULTS: A response rate of 50% (132 of 264 residents' members of MSNS) was obtained and considered for analysis. Median age was 30.06 ± 2.48 years, 5.3% (n = 7) were female and 16.7% (n = 22) were foreigners undergoing neurosurgical training in Mexico. Approximately 27% of respondents suffered any form of discrimination, mainly by place of origin (9.1%), by gender (8.3%) or by physical appearance (6.1%). About 42.9% (n = 3) of female residents were discriminated by gender versus 6.4% (n = 8) of male residents (P = 0.001); while foreign residents mentioned having suffered 10 times more an event of discrimination by place of origin compared to native Mexican residents (36.4% vs. 3.6%, P < 0.001). CONCLUSION: This manuscript represents the first approximation to determine the impact of discrimination suffered by residents undergoing neurosurgical training in Mexico before the SARS-CoV-2 pandemic.

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BACKGROUND: Sweetpotato and potato are fast-maturing staple crops and widely consumed in low- and middle-income countries. Conventional breeding to biofortify these crops with iron could improve iron intakes. To our knowledge, iron absorption from sweetpotato and potato has not been assessed. OBJECTIVE: The aim was to assess iron absorption from regular and iron-biofortified orange-fleshed sweetpotato in Malawi and yellow-fleshed potato and iron-biofortified purple-fleshed potato in Peru. METHODS: We conducted 2 randomized, multiple-meal studies in generally healthy, iron-depleted women of reproductive age. Malawian women (n = 24) received 400 g regular or biofortified sweetpotato test meals and Peruvian women (n = 35) received 500 g regular or biofortified potato test meals. Women consumed the meals at breakfast for 2 wk and were then crossed over to the other variety. We labeled the test meals with 57Fe or 58Fe and measured cumulative erythrocyte incorporation of the labels 14 d after completion of each test-meal sequence to calculate iron absorption. Iron absorption was compared by paired-sample t tests. RESULTS: The regular and biofortified orange-fleshed sweetpotato test meals contained 0.55 and 0.97 mg Fe/100 g. Geometric mean (95% CI) fractional iron absorption (FIA) was 5.82% (3.79%, 8.95%) and 6.02% (4.51%, 8.05%), respectively (P = 0.81), resulting in 1.9-fold higher total iron absorption (TIA) from biofortified sweetpotato (P < 0.001). The regular and biofortified potato test meals contained 0.33 and 0.69 mg Fe/100 g. FIA was 28.4% (23.5%, 34.2%) from the regular yellow-fleshed and 13.3% (10.6%, 16.6%) from the biofortified purple-fleshed potato meals, respectively (P < 0.001), resulting in no significant difference in TIA (P = 0.88). CONCLUSIONS: FIA from regular yellow-fleshed potato was remarkably high, at 28%. Iron absorbed from both potato test meals covered 33% of the daily absorbed iron requirement for women of reproductive age, while the biofortified orange-fleshed sweetpotato test meal covered 18% of this requirement. High polyphenol concentrations were likely the major inhibitors of iron absorption. These trials were registered at www.clinicaltrials.gov as NCT03840031 (Malawi) and NCT04216030 (Peru).

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El músculo grácil (MG) está ubicado en la cara medial del muslo, medial y posterior al aductor largo en su parte proximal. Se origina a nivel del pubis y se inserta en la cara medial de la tibia, en su parte superior. Como colgajo libre funcional ha sido uno de los injertos más utilizados en reconstrucciones diversas, tales como pene, perineo, vagina, pierna, plexo braquial, parálisis facial, lesiones rectales, entre otras. Basado en lo anterior, el objetivo de este estudio fue complementar la anatomía del MG tanto en sus dimensiones como en sus pedículos vasculares e inervación, estableciendo las relaciones biométricas existentes, contribuyendo a la anatomía quirúrgica, en su uso como injerto. Para ello, se utilizaron 30 miembros inferiores de 20 cadáveres de individuos adultos, brasileños, de sexo masculino, 14 derechos y 16 izquierdos; 17 fijados en formol y 13 en glicerina. Se dividió al muslo en 4 cuartiles enumerados de proximal a distal como C1,C2,C3 y C4. Se contabilizó el número de pedículos y se nombraron como pedículo principal (PP), pedículo menor 1 (Pm1), pedículo menor 2 (Pm2) y pedículo menor 3 (Pm3). La longitud media del GM fue de 42,25 cm ± 2,35 cm y su ancho promedio de 32,90 ± 4,86 mm. Con respecto a los pedículos vasculares se encontró un pedículo en 10/30 casos (33,3 %); un pedículo principal y uno menor en 10/30 (33,3 %); un pedículo principal y dos menores en 8/30 (26,7 %) y un pedículo principal y tres menores en 2/30 (6,7 %). Su inervación siempre procedió del ramo anterior del nervio obturador (RaNO). El punto motor se encontró a una distancia promedio de 7,94 mm proximal al ingreso del pedículo principal en el MG. Los registros biométricos están expresados en tablas. Los resultados obtenidos aportarán al conocimiento anatómico, pudiendo ser utilizados como soporte morfológico a los procedimientos quirúrgicos que involucren al músculo grácil.

The gracilis muscle (GM) is located in the medial aspect of the thigh, medial and posterior to the long adductor in its proximal part. It originates at the pubic level and is inserted in the medial face of the tibia, in its upper part. As a functional free flap, it has been one of the most co mmonly used grafts in various reconstructions, such as penis, perineum, vagina, leg, brachial plexus, facial paralysis, rectal lesions, among others. Based on the above, the objective of this study was to complement the anatomy of the GM both in its dimensions and in its vascular pedicles and innervation, establishing the existing biometric relationships, contributing to the surgical anatomy, in its use as a graft. For this, 30 lower limbs of 20 bodies of adult, Brazilian, male, 14 right and 16 left individuals were used; 17 fixed in formaldehyde and 13 in glycerin. The thigh was divided into 4 quartiles listed from proximal to distal such as C1, C2, C3 and C4. The number of pedicles was counted and they were named as principal pedicle (PP), minor pedicle 1 (mP1), minor pedicle 2 (mP2) and minor pedicle 3 (mP3). The average length of the GM was 42.25 cm ± 2.35 cm and its average width was 32.90 ± 4.86 mm. With respect to vascular pedicles, a pedicle was found in 10/30 cases (33.3 %); one PP and one mP in 10/30 (33.3 %); one PP and two mP in 8/30 (26.7 %) and one PP and three mP in 2/30 (6.7 %). Its innervation always came from the anterior branch of the obturator nerve (aBON). The motor point was found at an average distance of 7.94 mm proximal to the entry of the PP in the GM. Biometric records are expressed in tables. The results obtained will contribute to anatomical knowledge, and can be used as morphological support for surgical procedures that involve the GM.

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