299 research outputs found
Plant emergence and maize (Zea mays L.) yield across multiple farmers’ fields
Context: Uneven crop stands result from natural variation in emergence time that is related to soil moisture and temperature, and variation of within-row plant-to-plant distance caused during planting operations. Understanding the effect of the spatial and temporal variation of plant emergence on crop yield can help farmers make improved management decisions about planting.
Objective: The objectives of this work were to i) compare the timing of maize plant emergence across and within sub-field yield stability zones, ii) evaluate the impact of delayed emergence on crop yield and yield components by yield stability zone, and iii) compare the effect of spatial and temporal variability of plant emergence on crop yield and yield components.
Methods: Ten experiments were conducted in farmers’ maize fields in Springport (Michigan, US), Portland (Michigan, US), and Parana (Entre Rios, Argentina). Several years of yield monitored data for each field were used to delimitate yield stability zones (YSZ). Individual plant emergence was recorded daily, across yield stability zones. Emerged plants were tagged and the distance between plants within the row was recorded and used to calculate plant growing space (cm2 plant−1), and to classify them within plant stand as uniform, double or skips. Tagged plants were hand harvested to analyze the individual plant yield, number and weight of grains, and total crop yield.
Results: Individual plant emergence time ranged from 3 to 31 days after planting (DAP). The variation in timing of plant emergence had a greater impact than the variation of within-row plant spacing on crop yield and yield components. In general, the impact was larger in stable low yield areas. On average, plant yield was reduced by 7 %, grain number by 6 %, and final crop yield by 8.5 % per day of emergence delay after planting. The greater variation in the days of emergence delay when compared to within-row plant spacing variation can be related to the small overall spatial variability within the rows.
Conclusions: Plant emergence temporal variability had a higher impact than within-row plant spatial variability on crop yield and its components. The decrease in maize yield caused by the delay in emergence was not statistically related to yield stability zones. However, a trend of a more negative impact of delayed emergence in the low yield stability zones was observed.
Implications: Understanding factors affecting the spatial and temporal plant emergence patterns of crops can help farmers optimize their planting operation and may help them with decisions on using more precise and tailored inputs (such as seed rate and nitrogen fertilizer) on different sub-field yield stability zones. Incorporating emergence data and information into crop models will also help improve yield simulation results.EEA ParanáFil: Albarenque, Susana. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Paraná; ArgentinaFil: Albarenque, Susana. Michigan State University. Department of Plant, Soil and Microbial Sciences; Estados UnidosFil: Basso, Bruno. Michigan State University. Department of Earth and Environmental Sciences; Estados UnidosFil: Basso, Bruno. Michigan State University. W.K. Kellogg Biological Station; Estados UnidosFil: Davidson, O. Environmental Protection Agency; Estados UnidosFil: Maestrini, B. Wageningen University & Research. Agrosystems Research Group; Países BajosFil: Melchiori, Ricardo Jose. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Paraná; Argentin
Short-term effects of focal muscle vibration on motor recovery after acute stroke: a pilot randomized sham-controlled study
Repetitive focal muscle vibration (rMV) is known to promote neural plasticity and long-lasting motor recovery in chronic stroke patients. Those structural and functional changes within the motor network underlying motor recovery occur in the very first hours after stroke. Nonetheless, to our knowledge, no rMV-based studies have been carried out in acute stroke patients so far, and the clinical benefit of rMV in this phase of stroke is yet to be determined. The aim of this randomized double-blind sham-controlled study is to investigate the short-term effect of rMV on motor recovery in acute stroke patients. Out of 22 acute stroke patients, 10 were treated with the rMV (vibration group–VG), while 12 underwent the sham treatment (control group–CG). Both treatments were carried out for 3 consecutive days, starting within 72 h of stroke onset; each daily session consisted of three 10-min treatments (for each treated limb), interspersed with a 1-min interval. rMV was delivered using a specific device (Cro®System, NEMOCO srl, Italy). The transducer was applied perpendicular to the target muscle's belly, near its distal tendon insertion, generating a 0.2–0.5 mm peak-to-peak sinusoidal displacement at a frequency of 100 Hz. All participants also underwent a daily standard rehabilitation program. The study protocol underwent local ethics committee approval (ClinicalTrial.gov NCT03697525) and written informed consent was obtained from all of the participants. With regard to the different pre-treatment clinical statuses, VG patients showed significant clinical improvement with respect to CG-treated patients among the NIHSS (p < 0.001), Fugl-Meyer (p = 0.001), and Motricity Index (p < 0.001) scores. In addition, when the upper and lower limb scales scores were compared between the two groups, VG patients were found to have a better clinical improvement at all the clinical end points. This study provides the first evidence that rMV is able to improve the motor outcome in a cohort of acute stroke patients, regardless of the pretreatment clinical status. Being a safe and well-tolerated intervention, which is easy to perform at the bedside, rMV may represent a valid complementary non-pharmacological therapy to promote motor recovery in acute stroke patients
Screening for potential hazard effects from a multitarget anthracycline on the cardiovascular system
Predictors of Postabsorptive Ghrelin Secretion after Intake of Different Macronutrients
Abstract
Context: Release of ghrelin, a gastrointestinal hormone regulating feeding and energy balance, is blunted in obesity, a condition associated with insulin resistance.
Objective: The objective was to identify anthropometric and metabolic predictors of postabsorptive ghrelin secretion.
Design: We evaluated ghrelin, insulin, glucose, and leptin secretion overnight and after intake of different macronutrients.
Subjects: Ten obese subjects (age, 31.8 ± 2.5 yr; body mass index, 43.4 ± 0.8 kg/m2) and six lean subjects (age, 33.5 ± 2.4 yr; body mass index, 21.8 ± 1.4 kg/m2) participated in the study.
Main Outcome Measures: The main outcome measures were resting energy expenditure (REE); fat mass; nighttime approximate entropy (ApEn) and synchronicity (cross-ApEn) of ghrelin, insulin, and leptin; insulin sensitivity by homeostatic model approach insulin-sensitivity (HOMA-S%); postabsorptive area under the curve (AUC); and Δ of ghrelin, insulin, glucose, and leptin after carbohydrate-, lipid-, and protein-rich test meals.
Results: Nighttime ApEn scores were higher in obese than lean subjects (P < 0.01). Cross-ApEn revealed a synchronicity between ghrelin-insulin, ghrelin-leptin, and insulin-leptin in both groups. Compared with baseline, ghrelin decreased significantly (P < 0.01) in lean and obese subjects after carbohydrates (42.2 vs. 28.5%; P < 0.05), lipids (40.2 vs. 26.2%; P < 0.01), and proteins (42.2 vs. 26.3%; P < 0.01) devoid of between-meal ghrelin differences. Significant associations occurred between nocturnal ghrelin ApEn and insulin (r = 0.53; P < 0.05), postmeal ghrelin AUCs and REE (r = −0.57; P < 0.05), and HOMA-S% (r = 0.52; P < 0.05), postmeal ghrelin Δ and HOMA-S% (r = 0.60; P < 0.05). REE (β = −0.57; P = 0.02) and ghrelin ApEn (β = −0.62; P = 0.01) were predictors of postmeal ghrelin AUC and Δ, respectively.
Conclusions: Obesity determined a decreased orderliness of ghrelin secretion and a relative loss of ghrelin-insulin synchrony. Postabsorptive ghrelin secretion decreased significantly both in obese and lean subjects, was related to insulin sensitivity, and was predicted by energy expenditure and hormone pulsatility
FITOTERAPIA NO CONTROLE DE PARASITOS GASTRINTESTINAIS DE RUMINANTES: ÊNFASE NO GÊNERO MENTHA E SEUS COMPONENTES BIOATIVOS
Essa revisão apresenta considerações acerca da relevância das infecções de parasitos gastrintestinais (PGI) em ruminantes, abordando a importância de fármacos antiparasitários no controle das helmintoses e demais alternativas. Foi realizada uma abordagem conceitual e histórica sobre o controle de PGI e o processo de desenvolvimento da resistência parasitária. Como alternativa da baixa eficácia de medicamentos, foi feita uma descrição detalhada sobre o uso de óleos essenciais (OE) e de componentes bioativos no controle das PGI em ruminantes. A produção de OE de plantas, passa pela composição química, técnicas de extração dos componentes, mecanismo de ação e ensaios para validação da sua atividade terapêutica, incluindo sua ação anti-helmíntica. Este artigo traz, na sua segunda parte, uma descrição detalhada de duas espécies do gênero Mentha, com foco em sua biologia, composição química e mecanismos de ação de seus OE. Dentro desse tópico, as espécies Mentha vilosa e M. piperita são as mais estudadas, bem como os seus componentes majoritários e bioativos; carvone e limoneno. Ao final do documento, discutimos sobre a técnica de cromatografia gasosa e espectrometria de massas, que se faz obrigatória para a identificação de compostos presentes em OE. Incluímos ainda, o detalhamento sobre tecnologias de nanoemulsão e suas vantagens na confecção de formulações mais estáveis, menos tóxicas aos hospedeiros e com potencial de aumentar a eficácia de fármacos contra as PGI, para o desenvolvimento de novos compostos fitoterápicos ecosustentáveis.This review presents considerations about the relevance of gastrointestinal parasite (GIP) infections in ruminants,
covering also the importance of antiparasitic drugs in the control of helminth infections and some other alternatives.
This document describes a conceptual and historical view of the development of routine GIP control and the process of development of drug resistance. As an alternative to the low efficacy of some products, a detailed description was made of the use of essential oils (EO) and their bioactive compounds in the control of GIP in ruminants. The production of EO from plants, goes through the chemical composition, techniques of extraction of components, mechanism of action and assays for the validation of their activity, including the anthelmintic activity. The present document brings, in its second part, a more detailed description of two species of the genus Mentha, focusing on their biology, chemical composition and the mechanism of action of their EO. Within this topic, the species of Mentha vilosa and M. piperita are better studied, as well as their chemical composition and bioactive components carvone and limonene. At the end, it is discussed the gas chromatography and mass spectrometry techniques that are useful to identify compounds present in EO. It was also included the details about nanoemulsion technologies and their advantages in obtaining a more stable formulation, less toxic to the host, with a great potential to increase anthelmintic efficacy against GIP, for the development of new herbal bioactive and ecofriendly compounds
Homozygous microdeletion of exon 5 in ZNF277 in a girl with specific language impairment
Peer reviewedPublisher PD
Age and gender dependence of pre-contrast T1-relaxation times in normal human myocardium at 1.5T using ShMOLLI
Homozygosity for a missense mutation in the 67 kDa isoform of glutamate decarboxylase in a family with autosomal recessive spastic cerebral palsy: parallels with Stiff-Person Syndrome and other movement disorders
Background
Cerebral palsy (CP) is an heterogeneous group of neurological disorders of movement and/or posture, with an estimated incidence of 1 in 1000 live births. Non-progressive forms of symmetrical, spastic CP have been identified, which show a Mendelian autosomal recessive pattern of inheritance. We recently described the mapping of a recessive spastic CP locus to a 5 cM chromosomal region located at 2q24-31.1, in rare consanguineous families.
Methods
Here we present data that refine this locus to a 0.5 cM region, flanked by the microsatellite markers D2S2345 and D2S326. The minimal region contains the candidate gene GAD1, which encodes a glutamate decarboxylase isoform (GAD67), involved in conversion of the amino acid and excitatory neurotransmitter glutamate to the inhibitory neurotransmitter γ-aminobutyric acid (GABA).
Results
A novel amino acid mis-sense mutation in GAD67 was detected, which segregated with CP in affected individuals.
Conclusions
This result is interesting because auto-antibodies to GAD67 and the more widely studied GAD65 homologue encoded by the GAD2 gene, are described in patients with Stiff-Person Syndrome (SPS), epilepsy, cerebellar ataxia and Batten disease. Further investigation seems merited of the possibility that variation in the GAD1 sequence, potentially affecting glutamate/GABA ratios, may underlie this form of spastic CP, given the presence of anti-GAD antibodies in SPS and the recognised excitotoxicity of glutamate in various contexts
Soil Organic Carbon and Nitrogen Feedbacks on Crop Yields under Climate Change
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A genome-wide scan for common alleles affecting risk for autism
Although autism spectrum disorders (ASDs) have a substantial genetic basis, most of the known genetic risk has been traced to rare variants, principally copy number variants (CNVs). To identify common risk variation, the Autism Genome Project (AGP) Consortium genotyped 1558 rigorously defined ASD families for 1 million single-nucleotide polymorphisms (SNPs) and analyzed these SNP genotypes for association with ASD. In one of four primary association analyses, the association signal for marker rs4141463, located within MACROD2, crossed the genome-wide association significance threshold of P < 5 × 10−8. When a smaller replication sample was analyzed, the risk allele at rs4141463 was again over-transmitted; yet, consistent with the winner's curse, its effect size in the replication sample was much smaller; and, for the combined samples, the association signal barely fell below the P < 5 × 10−8 threshold. Exploratory analyses of phenotypic subtypes yielded no significant associations after correction for multiple testing. They did, however, yield strong signals within several genes, KIAA0564, PLD5, POU6F2, ST8SIA2 and TAF1C
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