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1.
Environ Res ; 246: 118047, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38160972

RESUMO

This study examines the potential for widespread solar photovoltaic panel production in Mexico and emphasizes the country's unique qualities that position it as a strong manufacturing candidate in this field. An advanced model based on artificial neural networks has been developed to predict solar photovoltaic panel plant metrics. This model integrates a state-of-the-art non-linear programming framework using Pyomo as well as an innovative optimization and machine learning toolkit library. This approach creates surrogate models for individual photovoltaic plants including production timelines. While this research, conducted through extensive simulations and meticulous computations, unveiled that Latin America has been significantly underrepresented in the production of silicon, wafers, cells, and modules within the global market; it also demonstrates the substantial potential of scaling up photovoltaic panel production in Mexico, leading to significant economic, social, and environmental benefits. By hyperparameter optimization, an outstanding and competitive artificial neural network model has been developed with a coefficient of determination values above 0.99 for all output variables. It has been found that water and energy consumption during PV panel production is remarkable. However, water consumption (33.16 × 10-4 m3/kWh) and the emissions generated (1.12 × 10-6 TonCO2/kWh) during energy production are significantly lower than those of conventional power plants. Notably, the results highlight a positive economic trend, with module production plants generating the highest profits (35.7%) among all production stages, while polycrystalline silicon production plants yield comparatively lower earnings (13.0%). Furthermore, this study underscores a critical factor in the photovoltaic panel production process which is that cell production plants contribute the most to energy consumption (39.7%) due to their intricate multi-stage processes. The blending of Machine Learning and optimization models heralds a new era in resource allocation for a more sustainable renewable energy sector, offering a brighter, greener future.


Assuntos
Energia Solar , México , Silício , Centrais Elétricas , Alocação de Recursos
2.
PeerJ ; 11: e14798, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36755868

RESUMO

Globally, microplastics (MP) represent a growing burden for ecosystems due to their increasing presence at different trophic levels. In Ecuador, the lack of waste segregation has increased the quantity of waste, primarily organics and plastics, overloading landfills and water sources. Over time, plastics reduce in size and silently enter the food chain of animals, such as insects. The black soldier fly (BSF) larvae, Hermetia illucens (Linnaeus, 1758), is a species with devouring behavior used for waste management because of its beneficial qualities such as fly pest control, biomass production, and rapid organic waste degradation. Studies have uncovered the insect's ability to tolerate MP, and consider the possibility that they may be able to degrade polymers. For the first time in Ecuador, the present study characterized H. illucens using the sequences of different molecular markers. Finally, H. illucens' degrading capacity was evaluated in the presence of MP and decaying food residues, resembling landfill conditions.


Assuntos
Dípteros , Ecossistema , Animais , Plásticos/metabolismo , Dípteros/genética , Larva/genética , Florestas , Variação Genética
3.
Sci Rep ; 11(1): 6185, 2021 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-33731771

RESUMO

Bioprospecting identifies new sources of compounds with actual or potential economic value that come from biodiversity. An analysis was performed regarding bioprospecting purposes in ten genotypes of Sechium spp., through a meta-analysis of 20 information sources considering different variables: five morphological, 19 biochemical, anti-proliferative activity of extracts on five malignant cell lines, and 188 polymorphic bands of amplified fragment length polymorphisms, were used in order to identify the most relevant variables for the design of genetic interbreeding. Significant relationships between morphological and biochemical characters and anti-proliferative activity in cell lines were obtained, with five principal components for principal component analysis (SAS/ETS); variables were identified with a statistical significance (< 0.7 and Pearson values ≥ 0.7), with 80.81% of the accumulation of genetic variation and 110 genetic bands. Thirty-nine (39) variables were recovered using NTSYSpc software where 30 showed a Pearson correlation (> 0.5) and nine variables (< 0.05), Finally, using a cladistics analysis approach highlighted 65 genetic bands, in addition to color of the fruit, presence of thorns, bitter flavor, piriform and oblong shape, and also content of chlorophylls a and b, presence of cucurbitacins, and the IC50 effect of chayote extracts on the four cell lines.


Assuntos
Bioprospecção , Cucurbitaceae , Cucurbitacinas/farmacologia , Frutas/química , Extratos Vegetais/farmacologia , Animais , Linhagem Celular , Cucurbitaceae/química , Cucurbitaceae/classificação , Cucurbitaceae/genética , Genótipo , Humanos , Camundongos , Polimorfismo Genético
4.
Front Plant Sci ; 12: 772389, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35756862

RESUMO

Natural products are in great demand because certain secondary metabolites (SMs) are sources of antioxidants, flavorings, active substances, or anticancer agents with less aggressiveness and selectivity, among which triterpenes and flavonoids are of importance because they inhibit carcinogenesis. For Sechium spp. P. Br. (chayotes), there is scientific evidence of antiproliferative activity that has occurred when cancer cell lines have been treated with this fruit. In order to compare future therapeutic designs and identify new and ancestral characteristics, triterpenes and flavonoids were determined in contrasting Sechium genotypes. The obtained data were analyzed via a cladistics approach, with the aim of identifying the characteristics and state of phytochemicals and genetic variables. The concentrations of flavonoids and triterpenes were determined, and a more complex composition of secondary metabolites was found in the wild types as compared to their domesticated genotypes. Bitter fruits contained a higher number of SMs, followed by those with a neutral and sweet flavor. A cladogram showed the differentiation of the three groups based on the flavor of the fruits. The diversity of SMs decreases in evolutionary terms, in response to domestication and environmental adaptation. Therefore, genotypes can be feasibly selected based on fruit flavor for gross-breeding, and cytotoxicity can be reduced without losing possible therapeutic effects.

5.
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-1354602

RESUMO

El propósito de este estudio fue determinar las diferencias en el rendimiento de las habilidades cognitivas entre 25 consumidores de cigarrillo y 25 consumidores de cannabis de 18 a 30 años (ambos grupos corresponden a estudiantes universitarios) y correlacionar su desempeño con el tiempo y frecuencia de consumo. Este estudio de tipo cuantitativo, no experimental- transversal, cuyo alcance fue descriptivo, comparativo y correlacional, evidenció que los consumidores de cannabis presentaron resultados significativamente menores en cada una de las habilidades cognitivas, especialmente en las funciones ejecutivas, siendo la habilidad que presentó peor desempeño en ambos grupos. Por otro lado, la habilidad que presenta una menor brecha entre los grupos es el lenguaje, habilidad que mostró tener un mejor rendimiento en los consumidores de marihuana en comparación con las demás habilidades. A pesar de los hallazgos, no fue posible establecer la relación entre el déficit de dichas habilidades y el tiempo y la frecuencia de consumo en ningún grupo debido a que la muestra estaba constituida por consumidores recientes. Se concluye que ambos tipos de consumo influyen en el déficit de las habilidades cognitivas a corto plazo, por lo cual es importante que equipos multidisciplinarios de profesionales especializados en el área de la salud consideren acciones de prevención e intervención en aquellos pacientes jóvenes que abusan del consumo tanto de sustancias lícitas como ilícitas con el fin de minimizar los efectos tanto en la salud física como en la cognitiva en la edad adulta.


The purpose of this study was to determine the differences in the performance of cognitive abilities between 25 cigarette and 25 cannabis smokers who were 18 to 30 years old (both groups correspond to university students) and to correlate their cognitive performance with time and frequency of consumption. This quantitative, non-experimental-transversal study, whose scope was descriptive, comparative and correlational, evidenced that cannabis smokers had significantly lower results in each cognitive ability, especially in executive functions, being the skill that presented the worst performance in both groups. On the other hand, the skill that presents the smallest gap between the groups is language, a skill that showed better performance in marijuana users, compared to the other skills. Despite the finding, it was not possible to establish the relationship between the deficit of these skills and the time and frequency of use in any group because the sample consisted of recent users. It is concluded that both types of consumption influence the deficit of cognitive skills in the short term, and for that reason is very important that multidisciplinary teams of professionals specialized in health area consider prevention and intervention actions in those young patients who abuse consumption of licit or illicit substances in order to minimize the effects on physical and cognitive health in adulthood.


Assuntos
Estudantes , Cannabis , Fumantes , Aptidão , Física , Sociedades , Tempo , Universidades , Saúde , Função Executiva , Produtos do Tabaco
6.
J Strength Cond Res ; 31(3): 809-816, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28222049

RESUMO

Flores, FJ, Sedano, S, and Redondo, JC. Optimal load and power spectrum during jerk and back jerk in competitive weightlifters. J Strength Cond Res 31(3): 809-816, 2017-Although the ability to develop high levels of power is considered as a key component of success in many sporting activities, the optimal load (Pmax load) that maximizes power output (Pmax) remains controversial mainly during weightlifting movements. The aim of the present study was to determine Pmax load and optimal power spectrum (OPS) required to elicit Pmax by comparing jerk and back jerk exercises in competitive weightlifters. Thirteen male competitive weightlifters participated in 2 testing sessions. The first session involved performing one repetition maximum (1RM) in the back jerk and jerk and the second session assessed a power test across a spectrum of loads (30-90%) of each subject's 1RM in the predetermined exercises tested. Relative load had a significant effect on peak power, with Pmax load being obtained at 90% of the subjects' 1RM in both exercises assessed. There was no significant difference between the power outputs at 80% of 1RM compared with 90% of 1RM. Furthermore, Pmax load and OPS were the same for jerk and back jerk, whereas peak power in the back jerk demonstrated no significant increases in every load of the power-load curve. We can conclude that it may be advantageous to use loads equivalent to 80-90% of the 1RM in jerk and back jerk in competitive weightlifters when training to maximize power.


Assuntos
Atletas , Movimento/fisiologia , Força Muscular/fisiologia , Levantamento de Peso/fisiologia , Adulto , Humanos , Masculino , Músculo Esquelético/fisiologia
7.
Mol Plant Microbe Interact ; 29(10): 750-766, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27578623

RESUMO

The inositol requiring enzyme (IRE1) is an endoplasmic reticulum (ER) stress sensor. When activated, it splices the bZIP60 mRNA, producing a truncated transcription factor that upregulates genes involved in the unfolded protein response. Bax inhibitor 1 (BI-1) is another ER stress sensor that regulates cell death in response to environmental assaults. The potyvirus 6K2 and potexvirus TGB3 proteins are known to reside in the ER, serving, respectively, as anchors for the viral replicase and movement protein complex. This study used green fluorescent protein (GFP)-tagged Turnip mosaic virus (TuMV), Plantago asiatica mosaic virus (PlAMV), Potato virus Y (PVY), and Potato virus X (PVX) to determine that the IRE1/bZIP60 pathway and BI-1 machinery are induced early in virus infection in Arabidopsis thaliana, Nicotiana benthamiana, and Solanum tuberosum. Agrodelivery of only the potyvirus 6K2 or TGB3 genes into plant cells activated bZIP60 and BI-1 expression in Arabidopsis thaliana, N. benthamiana, and S. tuberosum. Homozygous ire1a-2, ire1b-4, and ire1a-2/ire1b-4 mutant Arabidopsis plants were inoculated with TuMV-GFP or PlAMV-GFP. PlAMV accumulates to a higher level in ire1a-2 or ire1a-2/ire1b-4 mutant plants than in ire1b-4 or wild-type plants. TuMV-GFP accumulates to a higher level in ire1a-2, ire1b-4, or ire1a-2/ire1b-4 compared with wild-type plants, suggesting that both isoforms contribute to TuMV-GFP infection. Gene silencing was used to knock down bZIP60 and BI-1 expression in N. benthamiana. PVX-GFP and PVY-GFP accumulation was significantly elevated in these silenced plants compared with control plants. This study demonstrates that two ER stress pathways, namely IRE1/bZIP60 and the BI-1 pathway, limit systemic accumulation of potyvirus and potexvirus infection. Silencing BI-1 expression also resulted in systemic necrosis. These data suggest that ER stress-activated pathways, led by IRE1 and BI-1, respond to invading potyvirus and potexviruses to restrict virus infection and enable physiological changes enabling plants to tolerate virus assault.


Assuntos
Arabidopsis/genética , Nicotiana/genética , Doenças das Plantas/imunologia , Potexvirus/fisiologia , Potyvirus/fisiologia , Sequência de Aminoácidos , Arabidopsis/imunologia , Arabidopsis/fisiologia , Arabidopsis/virologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Genes Reporter , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Filogenia , Doenças das Plantas/virologia , Folhas de Planta/genética , Folhas de Planta/imunologia , Folhas de Planta/virologia , Splicing de RNA , RNA Mensageiro/genética , Alinhamento de Sequência , Nicotiana/imunologia , Nicotiana/fisiologia , Nicotiana/virologia , Ativação Transcricional
8.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 6): o1078-9, 2008 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-21202595

RESUMO

The title compound, C(27)H(39)N(3)O(2)·H(2)O, is a chiral pyridine-2,6-dicarboxamide derivative including cis-myrtanyl groups as amine substituents. The pyridine-2,6-dicarboxamide core approximates C(2) point symmetry and a solvent water mol-ecule lies on the pseudo-twofold axis. The water mol-ecule serves both as acceptor and donor for efficient hydrogen bonds involving N-H and C=O functional groups as donor and acceptor groups, respectively. As a result, each water mol-ecule in the crystal structure is tetra-hedrally bonded to three symmetry-related mol-ecules, forming a three-dimensional supra-molecular network. Such an arrangement is a common feature found in the majority of X-ray-characterized sym-metrically substituted pyridine-2,6-dicarboxamide derivatives.

9.
Cent Eur J Public Health ; 15(2): 71-3, 2007 06.
Artigo em Inglês | MEDLINE | ID: mdl-17645221

RESUMO

Skin tumors are the most frequent malignancies in the white population worldwide and have reached the proportion of an epidemic disease. Since non-melanocytic skin cancers can be cured when timely detected, given that still malignant melanoma may have good prognosis if early diagnosed, and considering the key role of primary care in cancer screening advising and implementation, the international PACMeR study group (trial_01.3) adjourned SESy_Europe database in a version comprehensive of skin-malignancies screening indexing. The novel database provides standardized pre-codified translations of 2,331 parameters in eight languages (English, French, German, Greek, Italian, Romanian, Spanish and Turkish) and records the time elapsed from last skin examination, cause and frequency of skins examinations and stratifies skin cancer risk patterns by a systematic registering of risk factors. A comprehensive indexing of skin cancer screening practices among European countries may in fact turn helpful in programming future health policy and tailoring interventions.


Assuntos
Bases de Dados como Assunto , Programas de Rastreamento/organização & administração , Neoplasias Cutâneas/diagnóstico , Europa (Continente) , Humanos
10.
Invest. med. int ; 16(4): 208-12, feb. 1990. tab
Artigo em Espanhol | LILACS | ID: lil-95536

RESUMO

Se estudiaron 362 niños de una escuela primaria de una zona marginada del estado de puebla, encontrando parasitosis intestinales en el 47.79%; se les administró albendazol a dosis de 400 mg dosis única (Ascaris I. y Enterobius v) y en caso de parasiosis por Trichuris t. se les administró 400 mg al día por tres días. Los resultados fueron altamente significativos con la prueba estadística de McNemar y no se reportaron efectos colaterales


Assuntos
Humanos , Criança , Anti-Helmínticos/administração & dosagem , Anti-Helmínticos/farmacocinética , Anti-Helmínticos , Helmintíase/terapia
11.
Ginecol. obstet. Méx ; 57: 153-7, oct. 1989. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-93738

RESUMO

Se analiza en forma prospectiva el comportamiento del tiempo de aceleración de tromboplastina en líquido amniótico (T.A.T. en L.A.) en 390 muestras, de las cuales correpondían 241 a embarazos normales y 149 a patológicos, (52 diabéticas y 97 hipertensas arteriales); con el fin de comparar este parámetro entre el embarazo normal y complicado. Se documentó que tal como ocurre el embarazo normal el T.A.T. en L.A. en el embarazo complicado se incrementa conforme avanza la gestación y así mismo su utilidad como prueba de madurez pulmonar fetal. Se concluye que tomando en cuenta su fácil disponibilidad, bajo costo y alta especificidad puede constituir un recurso de primera elección para documentar madurez pulmonar en centros de atención obstétrica de bajos recursos


Assuntos
Gravidez , Humanos , Feminino , Aceleração , Líquido Amniótico , Pressão Sanguínea , Maturidade dos Órgãos Fetais , Gravidez em Diabéticas , Tromboplastina , México
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