125 research outputs found
The supplementary irrigation effects on drought tolerance and ornamental characteristics of safflower varieties
Supplementary irrigation is a high-performance operation for increasing crop production and income of farmers in dryland conditions. In order to study the effect of supplementary irrigation on drought tolerance and ornamental characteristics of safflower genotypes an experiment was conducted in 2013-14 at North Khorasan Dryland Agricultural Research Station. The experimental design was split plot based on RCBD. Factors were included five levels of irrigation, i.e., no irrigation, irrigation at rosette stage, flowering stage, seed filling and irrigation in flowering + seed filling as the main factors, and sub factors were varieties in three levels included Feraman, Sina and Syrian. The effect of supplementary irrigation on harvest index, seed/main head, seed/sub head, thousand kernel weight and seed yield was significant. The effect of supplementary irrigation on traits: RGR, CGR, hollow seeds, number of flowers and flower size was not significant. The highest yield and harvest index were obtained with irrigation at flowering stage in "Feraman". Since the "Feraman" variety has shiny red flowers and spineless leaves, is a good plant for flower trade.Keywords: carthamus tinctorius; flower color; optimum irrigation; spineless leaf
Study of Growth Traits of Scindapsus spp. as Influenced By Fertigation of Humic Acid and Folvic Acid
Introduction Unbalanced and frequent use of chemical fertilizers and pesticides results in the degradation of soil physicochemical properties, loss of soil-born organisms, reduction of quality of produced crops and reduction of yield plant. Nowadays, due to environmental considerations of chemical fertilizers, use of organic acids for quantitative and qualitative improvement of crops has been increased. Humic materials are natural organic compounds that contain 50 to 90% of organic matters of peat, wood coal and rotten material, as well as non-living organic matters of aquatic and terrestrial ecosystems. Humic compounds indirectly increase soil fertility by providing micro- and macro-elements for root, improving soil structure, increasing medium permeability to water and air, increasing soil microbial population and beneficial microorganisms, increasing cation exchange capacity and the ability to buffer pH of medium or nutrient solution, and providing some special substances for plant roots such as nucleic acids and acetamides.Materials and Methods In order to investigate the influence of humic and fulvic acids on some growth characteristics in ornamental plant of Scindapsus spp., an experiment was conducted based on a completely randomized design with three replications at greenhouse in Ferdowsi University of Mashhad during 2014-2015. The first factor was humic acid in four levels of 0, 0.2, 0.5, 1 g/l, and the second factor was fulvic acid in four levels of 0, 0.2, 0.5, 1 g/l. Cuttings were taken from the plant in late March. Two weeks after transferring the rooted cuttings to pot, the treatments were applied on plants via fertigation. The traits measured in the experiment included plant height, mean number of nodes, internode length, leaf number, leaf length, leaf width, leaf area, root length, root fresh weight, leaf fresh weight, shoot fresh weight, aerial organ fresh weight, root volume, aerial organ volume, root dry weight, leaf dry weight, shoot dry weight, aerial organ dry weight, fresh and dry weights ratios of aerial organ to fresh weight. Statistical analysis of data was performed by 8-JMP software. LSD test was used to compare the means of the data.Results and Discussion Based on the results obtained, the combined use of humic acid and fulvic acid had a significant effect on height, fresh and dry weights of leaf, shoot, aerial organ and root, number of node and leaf and volume of aerial organ, fresh and dry weights of root, length and volume of root and the ratio of fresh and dry weights of aerial organ to root. Thus, combined use of humic acid and fulvic acid caused an increase in all the measured traits compared to the control treatment. Furthermore, an increase was observed in the length, width, and area of leaf, and internode length as the result of application of humic substances when compared to the control treatment. Organic fertilizers increase plant growth by improving soil conditions and increasing availability of plant to nutrients. Humic compounds cause changes in the specific distribution of cytokinins, polyamines and ATP by affecting the activity of root H+-ATPase and the distribution of root nitrate in the stem, thus affecting the growth of the plant stem. Humic materials increase plant growth by using different mechanisms such as hormonal effects, direct effect on plant cell metabolism, increase of cell division, chelating power and nutrient uptake, increase of soil ventilation and enhancement of plant photosynthesis by increasing Rubisco enzyme activity. Increasing nitrogen uptake leads to the increase in the growth of shoots and aerial organs. It also increases the number of branches in plants and increases the production of dry matter by increasing the production of photosynthetic materials.Conclusion In general, according to the results of this experiment, it can be concluded that application of humic substances (humic acid and fulvic acid) together, improved the growth characteristics of the plant and led to the better growth of the plant; therefore, these materials can be a good alternative to plant growth-stimulating chemical fertilizers
The association of alcohol consumption with mammographic density in a multiethnic urban population
Background
Alcohol consumption is associated with higher breast cancer risk. While studies suggest a modest association between alcohol intake and mammographic density, few studies have examined the association in racial/ethnic minority populations.
Methods
We assessed dense breast area and total breast area from digitized film mammograms in an urban cohort of African American (42%), African Caribbean (22%), white (22%), and Hispanic Caribbean (9%) women (n = 189, ages 40-61). We examined the association between alcohol intake and mammographic density (percent density and dense area). We used linear regression to examine mean differences in mammographic density across alcohol intake categories. We considered confounding by age, body mass index (BMI), hormone contraceptive use, family history of breast cancer, menopausal status, smoking status, nativity, race/ethnicity, age at first birth, and parity.
Results
Fifty percent currently consumed alcohol. Women who consumed >7 servings/week of alcohol, but not those consuming ≤7 servings/week, had higher percent density compared to nondrinkers after full adjustments (servings/week >7 β = 8.2, 95% Confidence Interval (CI) 1.8, 14.6; ≤7 β = -0.5, 95% CI -3.7, 2.8). There was a positive association between high alcohol intake and dense area after full adjustments (servings/week >7 β = 5.8, 95% CI -2.7, 14.2; ≤7 β = -0.1, 95% CI -4.4, 4.2). We did not observe race/ethnicity modification of the association between alcohol intake and percent density. In women with a BMI of 7 servings/week of alcohol had a 17% increase in percent density compared to nondrinkers (95% CI 5.4, 29.0) and there was no association in women with a BMI ≥ 25 kg/m2 (BMI ≥ 25-30 kg/m2 > 7 β = 5.1, 95% CI -8.5, 18.7 and BMI > 30 kg/m2 > 7 β = 0.5, 95% CI -6.5, 7.5) after adjusting for age and BMI (continuous).
Conclusion
In a racially/ethnically diverse cohort, women who consumed >7 servings/week of alcohol, especially those with a BMI < 25 kg/m2, had higher percent density.
Keywords: Mammographic breast density; Alcohol consumption; Breast cance
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Hair product use, age at menarche and mammographic breast density in multiethnic urban women
Background: Select hair products contain endocrine disrupting chemicals (EDCs) that may affect breast cancer risk. We hypothesize that, if EDCs are related to breast cancer risk, then they may also affect two important breast cancer risk factors: age at menarche and mammographic breast density. Methods: In two urban female cohorts (N = 248): 1) the New York site of the National Collaborative Perinatal Project and 2) the New York City Multiethnic Breast Cancer Project, we measured childhood and adult use of hair oils, lotions, leave-in conditioners, root stimulators, perms/relaxers, and hair dyes using the same validated questionnaire. We used multivariable relative risk regression models to examine the association between childhood hair product use and early age at menarche (defined as <11 years of age) and multivariable linear regression models to examine the association between childhood and adult hair product use and adult mammographic breast density. Results: Early menarche was associated with ever use of childhood hair products (RR 2.3, 95% CI 1.1, 4.8) and hair oil use (RR 2.5, 95% CI 1.2, 5.2); however, additional adjustment for race/ethnicity, attenuated associations (hair products RR 1.8, 95% CI 0.8, 4.1; hair oil use RR 2.3, 95% CI 1.0, 5.5). Breast density was not associated with adult or childhood hair product or hair oil use. Conclusions: If confirmed in larger prospective studies, these data suggest that exposure to EDCs through hair products in early life may affect breast cancer risk by altering timing of menarche, and may operate through a mechanism distinct from breast density
Effects of Vitamin D Supplementation on a Deep Learning-Based Mammographic Evaluation in SWOG S0812
Deep learning-based mammographic evaluations could noninvasively assess response to breast cancer chemoprevention. We evaluated change in a convolutional neural network-based breast cancer risk model applied to mammograms among women enrolled in SWOG S0812, which randomly assigned 208 premenopausal high-risk women to receive oral vitamin D3 20 000 IU weekly or placebo for 12 months. We applied the convolutional neural network model to mammograms collected at baseline (n = 109), 12 months (n = 97), and 24 months (n = 67) and compared changes in convolutional neural network-based risk score between treatment groups. Change in convolutional neural network-based risk score was not statistically significantly different between vitamin D and placebo groups at 12 months (0.005 vs 0.002, P = .875) or at 24 months (0.020 vs 0.001, P = .563). The findings are consistent with the primary analysis of S0812, which did not demonstrate statistically significant changes in mammographic density with vitamin D supplementation compared with placebo. There is an ongoing need to evaluate biomarkers of response to novel breast cancer chemopreventive agents
Adherence to Cancer Prevention Guidelines in 18 African Countries
Background
Cancer rates in Africa are projected to double by 2030 due to aging and increased exposure to cancer risk factors, including modifiable risk factors. We assessed adherence to 5 modifiable cancer risk factors across 18 African countries.
Methods
Data on adults 18 years and older were obtained from the 2002–2004 World Health Survey. Adherence to current World Cancer Research Fund guidelines on smoking, alcohol, body weight, physical activity, and nutrition was assessed. Adherence scores ranged from 0 (no guideline met) to 5 (all guidelines met). Determinants of adherence were assessed using multivariable linear regression adjusted for individual and country level characteristics.
Results
Across all countries, adherence to the guidelines among adults was high for smoking (72%–99%) and alcohol (85%–100%), but low for body weight (1.8%–78%), physical activity (3.4%–84%) and nutrition (1.4%–61%). Overall adherence score ranged from 2.32 in Mali to 3.72 in Comoros. In multivariable models, residing in low versus high SES households was associated with reduced adherence by 0.24 and 0.21 points for men and women respectively after adjusting for age, gender, education, and marital status (p<0.001). Every % increase in GDP spent on health was associated with increased adherence by 0.03 in men and 0.09 in women (p<0.001).
Conclusions
The wide variation in adherence to cancer prevention guidelines observed across countries and between population sub-groups suggests the need for targeted public health efforts to improve behaviors related to body weight, physical activity and nutrition
Birth weight and the risk of atrial fibrillation in whites and African Americans: The atherosclerosis risk in communities (ARIC) study
Background: Low birth weight (LBW) has been associated with an increased risk of cardiovascular disease (CVD). A previous study, however, found higher risk of atrial fibrillation (AF) in individuals with higher birth weight (BW). To further understand this apparent paradox, we examined the relationship between AF and BW in the Atherosclerosis Risk in Communities (ARIC) cohort. Methods: The analysis included 10,132 individuals free of AF at baseline (1996-1998), who provided BW information, were not born premature, and were not a twin. Self-reported BW was categorized as low (<2.5 kg), medium (2.5-4 kg), and high (>4.0 kg). AF incidence was ascertained from hospital discharge codes and death certificates. We used multivariable Cox proportional hazard models to determine the hazard ratios (HR) and 95% confidence intervals (CI) of AF across BW groups. Results: During an average follow-up of 10.3 years, we identified 882 incident AF cases. LBW was associated with higher risk of AF. Compared to individuals in the medium BW category, the HR (95% CI) of AF was 1.33 (0.99, 1.78) for LBW and 1.00 (0.81, 1.24) for high BW after adjusting for sociodemographic variables (p for trend = 0.29). Additional adjustment for CVD risk factors did not attenuate the associations (HR 1.42, 95% CI 1.06, 1.90 for LBW and HR 0.86, 95% CI 0.69-1.07 for high BW, compared to medium BW, p for trend = 0.01).Conclusion: LBW was associated with a higher risk of AF. This association was independent of known predictors of AF and is consistent with that observed for other cardiovascular diseases. © 2014 Lawani et al.; licensee BioMed Central Ltd
Maternal marijuana use has independent effects on risk for spontaneous preterm birth but not other common late pregnancy complications
Widespread legalisation of marijuana raises safety concerns for its use in pregnancy. This study investigated the association of marijuana use prior to and during pregnancy with pregnancy outcomes in a prospective cohort of 5588 nulliparous women from the international SCOPE study. Women were assessed at 15 ± 1 and 20 ± 1 weeks’ gestation. Cases [278 Preeclampsia, 470 gestational hypertension, 633 small-for-gestational-age, 236 spontaneous preterm births (SPTB), 143 gestational diabetes] were compared separately with 4114 non-cases. Although the numbers are small, continued maternal marijuana use at 20 weeks’ gestation was associated with SPTB independent of cigarette smoking status [adj OR 2.28 (95% CI:1.45–3.59)] and socioeconomic index (SEI) [adj OR 2.17 (95% CI:1.41–3.34)]. When adjusted for maternal age, cigarette smoking, alcohol and SEI, continued maternal marijuana use at 20 weeks’ gestation had a greater effect size [adj OR 5.44 (95% CI 2.44–12.11)]. Our data indicate that increasing use of marijuana among young women of reproductive age is a major public health concern
Childhood body size and pubertal timing in relation to adult mammographic density phenotype
Background: An earlier age at onset of breast development and longer time between pubertal stages has been implicated in breast cancer risk. It is not clear whether associations of breast cancer risk with puberty or predictors of onset of puberty, such as weight and height, are mediated via mammographic density, an important risk factor for breast cancer. Methods: We investigated whether childhood body size and pubertal timing and tempo, collected by questionnaire, are associated with percentage and absolute area mammographic density at ages 47-73 years in 1105 women recruited to a prospective study. Results: After controlling for adult adiposity, weight at ages 7 and 11 years was strongly significantly inversely associated with percentage and absolute dense area (p trend < 0.001), and positively associated with absolute nondense area. Greater height at age 7, but not age 11, was associated with lower percentage density (p trend = 0.016). Later age at menarche and age at when regular periods were established was associated with increased density, but additional adjustment for childhood weight attenuated the association. A longer interval between thelarche and menarche, and between thelarche and regular periods, was associated with increased dense area, even after adjusting for childhood weight (p trend = 0.013 and 0.028, respectively), and was independent of age at pubertal onset. Conclusions: Greater prepubertal weight and earlier pubertal onset are associated with lower adult breast density, but age at pubertal onset does not appear to have an independent effect on adult density after controlling for childhood adiposity. A possible effect of pubertal tempo on density needs further investigation
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