606 research outputs found
Sugarcane yields prediction at the row level using a novel cross-validation approach to multi-year multispectral images
Early prediction of sugarcane crop yield would benefit sugarcane growers and policymakers by allowing for timely decisions. The primary objective of this study was to reduce reliance on satellite images and improve early prediction of sugarcane yield at row level by using high-resolution multispectral Unmanned Aerial Vehicle (UAV) imagery. To our knowledge, no previous study has evaluated the performance of multispectral UAV-derived vegetation indices in sugarcane crops at the crop row level. In this study, we used UAV mapping on 48 rows of sugarcane at three main growth stages (early, middle, and mature) over three growing seasons. A secondary objective was to predict future sugarcane yields at the earliest possible stage of growth. The results showed that the optimal growth stage for all 23 VIs varied, but the middle stage, from mid-March to early May, was the most prevalent. Further detailed analysis in the middle stage revealed that March was the best month for predicting future sugarcane yields when compared to April and May. This result is approximately a month earlier than previous studies in the same region. Following two stages of feature selection, such as Pearson correlation analysis and stepwise feature selection, a novel cross-validation methodology based on a generalized linear model trained and tested the yield prediction models on various combinations of the VIs. This novel methodology improves model accuracy by avoiding overfitting and over complexity caused by interdependent VIs, and then validates the model generality using previously unseen data. The best performance was achieved by combining the Normalized Difference RedEdge (NDRE) and the Green–Red Normalized Difference Vegetation Index (GRNDVI) at March. These results help growers and decision-makers benefit from early row-level yield forecast, six months before harvest, if UAV mapping is available
An investigation on the best-fit models for sugarcane biomass estimation by linear mixed-effect modelling on unmanned aerial vehicle-based multispectral images: A case study of Australia
Due to the worldwide population growth and the increasing needs for sugar-based products, accurate estimation of sugarcane biomass is critical to the precise monitoring of sugarcane growth. This research aims to find the imperative predictors correspond to the random and fixed effects to improve the accuracy of wet and dry sugarcane biomass estimations by integrating ground data and multi-temporal images from Unmanned Aerial Vehicles (UAVs). The multispectral images and biomass measurements were obtained at different sugarcane growth stages from 12 plots with three nitrogen fertilizer treatments. Individual spectral bands and different combinations of the plots, growth stages, and nitrogen fertilizer treatments were investigated to address the issue of selecting the correct fixed and random effects for the modelling. A model selection strategy was applied to obtain the optimum fixed effects and their proportional contribution. The results showed that utilizing Green, Blue, and Near Infrared spectral bands on models rather than all bands improved model performance for wet and dry biomass estimates. Additionally, the combination of plots and growth stages outperformed all the candidates of random effects. The proposed model outperformed the Multiple Linear Regression (MLR), Generalized Linear Model (GLM), and Generalized Additive Model (GAM) for wet and dry sugarcane biomass, with coefficients of determination (R2) of 0.93 and 0.97, and Root Mean Square Error (RMSE) of 12.78 and 2.57 t/ha, respectively. This study indicates that the proposed model can accurately estimate sugarcane biomasses without relying on nitrogen fertilizers or the saturation/senescence problem of Vegetation Indices (VIs) in mature growth stages
The effect of radiotherapy and chemotherapy on osmotic fragility of red blood cells and plasma levels of malondialdehyde in patients with breast cancer
Background: Gamma radiation effects on the erythrocyte membrane from three different functional parts, lipid bilayer, cytoskeleton and protein components. When the red cell membrane is exposed to radiation, it loses its integrity and hemoglobin leaks out. In addition, irradiation leads to lipid peroxidation and the products of this process, leading to hemolysis. The aim of the present study was to measure osmotic fragility (OF) of red blood cells and malondialdehyde (MDA) levels as a marker of oxidative injury in breast cancer patients treated with radiation and chemotherapy. Materials and Methods: The OF test was performed using different concentrations of a salt solution. The measurement of MDA was done with chemical methods.11 The sampling was taken during three stages of treatment: first sample was taken before starting chemotherapy, the second sample was taken before radiation therapy and the third sample was taken after radiotherapy. Results: No statistically significant differences between levels of MDA in these three stages of treatment were observed. However, the comparison of mean levels of MDA showed an increase after radiotherapy. The OF rate did not show significant difference (P > 0.05) during the stages of treatment. Conclusion: In a standard treatment program of radiotherapy and chemotherapy lipid peroxidation level and OF do not significantly increase. © 2014 Greater Poland Cancer Centre
Association of socio-economic status and visual impairment: A population-based study in Iran
Backgrounds: To assess the role of socio-economic inequality in visual impairment (VI) in Varamin district, Iran. Patients and Methods: Using multistage cluster sampling method, 60 clusters (each with 50 subjects) were recruited and underwent clinical eye examinations. Socio-economic status (SES) was identified based on education, occupation, family assets and housing conditions that were measured at the participants’ households using a semi-structured questionnaire and a two-step cluster analysis model. In addition, principal component analysis and the concentration index were used to identify the gap between high and low SES groups. Results: Participants were categorized in high (522, 24.4%), moderate (974, 43.1%) and low (763, 33.7%) socio-economic levels. In these levels, the prevalence of VI was 5.9% (95% CI: 3.3 to 8.6), 10.4% (95% CI: 8.4-12.4), and 12.6% (95% CI: 10.1 to 15.1), respectively. The prevalence of VI in people with low SES was significantly greater than those in high SES level. The proportions of avoidable causes were relatively high in all SES levels (more than 80%) with no significant difference between different levels. Conclusions: There is significant inequality in VI prevalence in Varamin district. Avoidable causes are high in all SES groups. Therefore, community-based modalities and preventive programs with a specific notice to poorer SES groups are recommended to improve eye health in this district. © 2017, Academy of Medical Sciences of I.R. Iran. All rights reserved
GAD1 mRNA Expression and DNA Methylation in Prefrontal Cortex of Subjects with Schizophrenia
Dysfunction of prefrontal cortex in schizophrenia includes changes in GABAergic mRNAs, including decreased expression of GAD1, encoding the 67 kDa glutamate decarboxylase (GAD67) GABA synthesis enzyme. The underlying molecular mechanisms remain unclear. Alterations in DNA methylation as an epigenetic regulator of gene expression are thought to play a role but this hypothesis is difficult to test because no techniques are available to extract DNA from GAD1 expressing neurons efficiently from human postmortem brain. Here, we present an alternative approach that is based on immunoprecipitation of mononucleosomes with anti-methyl-histone antibodies differentiating between sites of potential gene expression as opposed to repressive or silenced chromatin. Methylation patterns of CpG dinucleotides at the GAD1 proximal promoter and intron 2 were determined for each of the two chromatin fractions separately, using a case-control design for 14 schizophrenia subjects affected by a decrease in prefrontal GAD1 mRNA levels. In controls, the methylation frequencies at CpG dinucleotides, while overall higher in repressive as compared to open chromatin, did not exceed 5% at the proximal GAD1 promoter and 30% within intron 2. Subjects with schizophrenia showed a significant, on average 8-fold deficit in repressive chromatin-associated DNA methylation at the promoter. These results suggest that chromatin remodeling mechanisms are involved in dysregulated GABAergic gene expression in schizophrenia
Replacing Sugar by Date Syrup in Gaz and Investigation of Texture Properties
Date Syrup is a natural sweetener that is suitable replacement for sugar in food stuffs formulation. In this Research Amounts of 25-100 percent of sugar in Gaz formulation were replaced with date syrup and to study effect of its use in product formulation, characteristics of texture, color and sensory analyse of treatments were investigated. Statistical analyse of data was also done by SPSS software and Dankan test. The results of this research showed that amount of used date syrup in formulation had a significant effect on color parameters (L*,a*,b*), texture characteristics and sensory analyse of samples. By increase of date syrup in Gaz formulation, samples texture became softer than control sample and yellowness and redness index of samples were increasedDoi: DOI: 10.12777/ijse.6.1.11-15 [How to cite this article: Shafiei, Z., Hojjatoleslami, M., Soha, S., and Shariati, M.A. 2014. The Influence of Malt Extraction Adding to UF Fresh Low Fat Cheese on Its Textural Properties. International Journal of Science and Engineering, 6(1):57-60. Doi: 10.12777/ijse.6.1.11-1
Dominant processes causing the formation of coastal sand masses, case study: western Makran coastal plain
The instability and mobility of sand dunes is a major concern for those involved in the planning processes and management of arid coastal plains. Dune systems are created due to several factors and elements. Regarding environmental planning and the management of coastal zones, the study of their formation and development processes is of great importance. The present study aims at identifying the most influential factors in the dispersion of sand masses in the western region of the Makran Plain. The data for this study consisted of spatial maps of landform distributions, wind velocities and directions, fetch lengths as well as dynamic waves. Thematic topographical and geological maps, satellite images, GPS, and software such as WRPLOT View, Freehand, and Arc GIS were used for data processing and analysis. After the generation of the Geomorphologic units map through the Molitor Equation in WRPLOT View, wind and wave rose diagrams were provided. Also, the elongation and direction of sand mass movements in the plain were obtained through multi-temporal and multisensory data. The main rivers’ monthly discharges were analyzed according to information gathered from previous studies as well as their relevant hydrometric water stations. Results indicated that the location and distribution of coastal sand masses are not affected by wind, but by the geomorphologic characteristics of foreshore and coastal hydrodynamics. Also, the distribution of internal sand masses on the coastal plain is affected mostly by the plain stretches relative to the prevailing wind direction and to the extent of old beds and floodplains that are exposed to the prevailing wind rather than the wind itself
Disease- and age-related changes in histone acetylation at gene promoters in psychiatric disorders
Increasing evidence suggests that epigenetic factors have critical roles in gene
regulation in neuropsychiatric disorders and in aging, both of which are
typically associated with a wide range of gene expression abnormalities. Here,
we have used chromatin immunoprecipitation-qPCR to measure levels of acetylated
histone H3 at lysines 9/14 (ac-H3K9K14), two epigenetic marks associated
with transcriptionally active chromatin, at the promoter regions of eight
schizophrenia-related genes in n=82 postmortem prefrontal
cortical samples from normal subjects and those with schizophrenia and bipolar
disorder. We find that promoter-associated ac-H3K9K14 levels are correlated with
gene expression levels, as measured by real-time qPCR for several genes,
including, glutamic acid decarboxylase 1 (GAD1), 5-hydroxytryptamine
receptor 2C (HTR2C), translocase of outer mitochondrial membrane 70
homolog A (TOMM70A) and protein phosphatase 1E (PPM1E).
Ac-H3K9K14 levels of several of the genes tested were significantly negatively
associated with age in normal subjects and those with bipolar disorder, but not
in subjects with schizophrenia, whereby low levels of histone acetylation were
observed in early age and throughout aging. Consistent with this observation,
significant hypoacetylation of H3K9K14 was detected in young subjects with
schizophrenia when compared with age-matched controls. Our results demonstrate
that gene expression changes associated with psychiatric disease and aging
result from epigenetic mechanisms involving histone acetylation. We further find
that treatment with a histone deacetylase (HDAC) inhibitor alters the expression
of several candidate genes for schizophrenia in mouse brain. These findings may
have therapeutic implications for the clinical use of HDAC inhibitors in
psychiatric disorders
Rupture of Splenic Artery Aneurysm With Portal Hypertension During Pregnancy: A Case Report
Background: Spontaneous rupture of a splenic artery aneurysm (SAA) during pregnancy is a rare event with catastrophic consequences. This report presents a case of SAA associated with portal hypertension that ruptured during pregnancy with maternal survival. Case: A 27-year-old primigravid woman at 31 weeks of gestation presented to the Emergency Department at Pars Hospital in Tehran, Iran with sudden onset of severe abdominal pain. She was in obvious distress with blood pressure of 90/50 mm Hg and a pulse rate of 110 beats per minute. Abdominal ultrasound confirmed free fluid in the peritoneal cavity. The patient was immediately transferred to the operating room. An infant delivered by Caesarean section died shortly thereafter. There was no evidence of placental abruption, but about 2 L of blood was noted in the abdominal cavity. A ruptured SAA was found. Proximal ligation of the splenic artery was performed followed by splenectomy. The patient did well and was discharged on the eighth postoperative day. Conclusion: This case illustrates the need to consider ruptured SAA as part of differential diagnosis of hemoperitoneum in pregnant women. Immediate surgical intervention is needed to ensure survival of mother and fetus. © 2006 Society of Obstetricians and Gynaecologists of Canada
Trends in ovarian cancer incidence in Iran
Background: Cancer is amajorcause of morbidityandmortality,amongwhichovarian cancer has a high incidenceandcase fatality. Gaining insight into the epidemiology and trends of ovarian cancer can be very influential in cancer screening and treatments programming. This study aimed to investigate the trends in the incidence of ovarian cancer in Iran, because this issue has been neglected so far. Methods: This study is a re-analysis of existing data from the cancer data recording system in Iran during the years 2003 to 2009. The incidence rates reported were standardized according to the world health organization (WHO) and the trend in the incidence of this disease was determined by STATA software and the significance of the morbidity trend diagram was also derived via WINPEPI software. Results: The statistics of cancer registry center shows an increasing trend of ovarian cancer from 2003 to 2008, while it decreased from 2008 to 2009. During this period, 6078 cases of ovarian cancer were registered in Iran, increasing from 591 cases in 2003 to 1077 in 2009, which shows an approximately 2-fold increase in the incidence of registered cases. During these seven years, the highest incidence rate was seen in Markazi province with 6.33 per 100,000 persons and the least in Kohkiloye-va-Boyerahmad province with zero incidence. Almost all provinces, except a few, had increasing incidence of ovarian cancer. Conclusions: According to the results of the study, the incidence of ovarian cancer is increasing in Iran, especially in the central and northwestern regions of the country. This increase may be due to changing the patterns of risk factors for this disease, such as changes in lifestyle in the population, which will lead to changes in the incidence of the disease. Hence, due to the increase in incidence of this cancer, it is recommended to implement screening and early detection programs in high risk areas and populations. © 2016, Iranian Journal of Cancer Prevention
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