High Negative Loadings Research Articles

Dietary patterns and the risk of diabetes in Korean adults: A cross-sectional and prospective cohort study

ObjectiveThe aim of this study was to identify dietary patterns associated with diabetes in Korean adults and to investigate their association with diabetes risk in both a cross-sectional and prospective study. MethodsPredefined food groups collected by the Korea National Health and Nutrition Examination Survey (KNHANES 2015–2018, n = 19 721) were entered in a reduced rank regression (RRR) model, followed by stepwise linear regression analyses to identify the most predictive dietary patterns. We evaluated the construct validity of dietary patterns in two independent samples from KNHANES 2019 to 2021 (n = 14 223) and the Health Examinees (HEXA) cohort study (n = 30 013). Associations between dietary patterns and diabetes risk were examined using multivariable regression and multivariable-adjusted Cox proportional hazard models, respectively. ResultsA dietary pattern was identified with high positive loadings for refined white rice, kimchi and salted vegetables, wheat flour and bread, and seasonings, and high negative loadings for whole grains, legumes with tofu and soymilk, poultry, eggs, and plant oils. The higher pattern scores were significantly associated with diabetes risk in KNHANES 2015 to 2018 (male: odds ratio [OR]: 1.59; 95% confidence interval [CI]: 1.35, 1.88; female: OR: 1.37; 95% CI: 1.18, 1.52), KNHANES 2019 to 2021 (male: OR: 1.47; 95% CI: 1.01, 1.69; female: OR: 1.37; 95% CI: 1.18, 1.54), and HEXA study (male: hazard ratio [HR]: 1.10; 95% CI: 1.01, 1.34; female: HR: 1.24; 95% CI: 1.02, 1.52). ConclusionsDietary patterns derived by RRR followed by stepwise linear regression analyses were associated with increased risks of diabetes among Korean adults.

Infants’ Dietary Pattern Characterized by Ultraprocessed Foods Is Associated With Rapid Weight Gain and Overweight/Obesity Risk: National Health and Nutrition Examination Survey 2009-2018

BackgroundGlobal trends toward childhood obesity have been associated with several factors, including suboptimal infant feeding practices, the increasing availability of ultraprocessed foods in the world's food supply, and the corresponding changes in children's dietary patterns. ObjectiveTo describe infants’ dietary patterns and assess their associations with weight status outcomes in a nationally representative sample of US infants. DesignCross-sectional analyses were performed on data collected from infants participating in the 2009-2018 National Health and Nutrition Examination Survey. Participants/settingParticipants included 744 infants aged 6 to 12 months who had data from at least 1 day of valid 24-hour dietary recall data. Main outcome measuresRapid weight gain and overweight/obesity risk. Statistical analyses performedPrincipal component analysis was used to identify dietary patterns considering the energy intake of 39 Nova food subgroups (expressed in calories per day), including breast milk. Associations were evaluated using logistic regression adjusted for potential confounders. ResultsA total of 42% infants experienced rapid weight gain, and 33% were at risk of overweight/obesity. Most infants (65.5%) were started on solid foods early. Three main dietary patterns were derived. The first pattern, labeled Natural or Minimally Processed Foods, had positive loadings for a variety of natural or minimally processed foods, some processed culinary ingredients, and a few processed and ultraprocessed foods. The second pattern, labeled Infant Formula, had high negative loading for breast milk, and high positive loading for infant formula and breakfast cereal. The third pattern, labeled Ultraprocessed Foods, had negative loadings for natural or minimally processed foods and processed culinary ingredients, positive loadings for other processed foods and for a variety of ultraprocessed foods, and negative loading for infant formula. Infants who adhere to the Ultraprocessed Foods dietary pattern were more likely to present rapid weight gain (adjusted odds ratio 1.3, 95% CI 1.1 to 1.5) and overweight/obesity risk (adjusted odds ratio 1.2, 95% CI 1.0 to 1.4). ConclusionsHigher adherence to a dietary pattern characterized by ultraprocessed foods was associated with a greater likelihood of both rapid weight gain and overweight/obesity risk early in life. Promoting breastfeeding and increasing consumption of unprocessed/minimally processed foods during early infancy while restricting ultraprocessed foods are key components to reducing the growing burden of childhood obesity.

Associations between dietary patterns and cardiovascular disease risk in Canadian adults: a comparison of partial least squares, reduced rank regression and the simplified dietary pattern technique.

ObjectivesWe aimed to compare two data reduction techniques, partial least squares (PLS) and reduced rank regression (RRR), in identifying dietary patterns associated with a high cardiovascular disease (CVD) risk in Canadian adults, and to construct PLS- and RRR-based simplified dietary patterns as well as evaluating associations between derived patterns and CVD risk.
 ApproachData were collected from 24-hour dietary recalls of adult respondents in two cycles of the nationally representative Canadian Community Health Survey (CCHS)-Nutrition: CCHS 2004 linked to health administrative databases (n = 12,313) and CCHS 2015 (n = 14,020). Using 39 food groups, PLS and RRR were applied for the identification of an energy-dense (ED), high-saturated-fat (HSF) and low-fiber-density (LFD) dietary pattern. Associations of derived dietary patterns with lifestyle characteristics and CVD incidence and mortality were examined using weighted multivariate regression and weighted multivariable-adjusted Cox-proportional hazard models, respectively. Random and systematic measurement errors were adjusted for in all statistical analyses.
 ResultsPLS and RRR identified highly similar ED, HSF, LFD dietary patterns with common high positive loadings for fast food, carbonated drinks, salty snacks and solid fats, and high negative loadings for fruit, dark green vegetables, red and orange vegetables, other vegetables, whole grains, legumes and soy (≥|0.17|). Food groups with the highest loadings were summed to form simplified pattern scores. Although the dietary patterns were not significantly associated with CVD risk, they were positively associated with 402 kcal/d higher energy intake (P-trends <0.05) and higher obesity risk [PLS (OR: 2.09; 95% CI: 1.62, 2.7) and RRR (OR: 1.76; 95% CI: 1.44, 2.17)] (P-trends <0.0001) in the fourth quartiles as compared to the first.
 ConclusionPLS and RRR were shown to be equally effective for derivation of a high-CVD-risk dietary pattern among Canadian adults. This research highlights the importance of leveraging linked data to inform public health nutrition policies. Further research is warranted on the role of major dietary components in cardiovascular health.

Associations between dietary patterns and cardiovascular disease risk in Canadian adults: a comparison of partial least squares, reduced rank regression, and the simplified dietary pattern technique

Hybrid methodologies have gained continuing interest as unique data reduction techniques for establishing a direct link between dietary exposures and clinical outcomes. We aimed to compare partial least squares (PLS) and reduced rank regression (RRR) in identifying a dietary pattern associated with a high cardiovascular disease (CVD) risk in Canadian adults, construct PLS- and RRR-based simplified dietary patterns, and assess associations between the 4 dietary pattern scores and CVD risk. Data were collected from 24-h dietary recalls of adult respondents in the 2 cycles of the nationally representative Canadian Community Health Survey (CCHS)-Nutrition: CCHS 2004 linked to health administrative databases (n = 12,313) and CCHS 2015 (n = 14,020). Using 39 food groups, PLS and RRR were applied for identification of an energy-dense (ED), high-saturated-fat (HSF), and low-fiber-density (LFD) dietary pattern. Associations of the derived dietary pattern scores with lifestyle characteristics and CVD risk were examined using weighted multivariate regression and weighted multivariable-adjusted Cox proportional hazard models, respectively. PLS and RRR identified highly similar ED, HSF, and LFD dietary patterns with common high positive loadings for fast food, carbonated drinks, salty snacks, and solid fats, and high negative loadings for fruit, dark green vegetables, red and orange vegetables, other vegetables, whole grains, and legumes and soy (≥|0.17|). Food groups with the highest loadings were summed to form simplified pattern scores. Although the dietary patterns were not significantly associated with CVD risk, they were positively associated with 402-kcal/d higher energy intake (P-trends < 0.05) and higher obesity risk (PLS: OR: 2.09; 95% CI: 1.62, 2.70; RRR: OR: 1.76; 95% CI: 1.44, 2.17) (P-trends < 0.0001) in the fourth quartiles. PLS and RRR were shown to be equally effective for the derivation of a high-CVD-risk dietary pattern among Canadian adults. Further research is warranted on the role of major dietary components in cardiovascular health.

Visceral adiposity-related dietary patterns and the risk of cardiovascular disease in Iranian adults: A population-based cohort study.

BackgroundVisceral obesity is a significant predictor of cardiovascular disease (CVD). Diet may associate with CVD risk through its effects on visceral adiposity. This study aimed to find dietary patterns (DPs) related to indicators of visceral adiposity and to determine whether the DPs were associated with CVD risk.MethodsThis prospective study included 2,496 participants of the Tehran Lipid and Glucose Study (TLGS) without CVD, who were followed from the third study examination (2005–2008; baseline) to March 2018. DPs at baseline were determined using reduced rank regression (RRR) and partial least squares regression (PLS). The response variables were age and BMI-adjusted waist circumference (WC) and age-adjusted visceral adiposity index (VAI).ResultsTwo and three DPs were retained with RRR and PLS, respectively. The first patterns of each method were mainly characterized by adjusted-WC (RRR: 10.8%, PLS: 8.6%); none of them were associated with CVD risk. The second pattern of RRR and the third pattern of PLS were mainly explained by adjusted-VAI (RRR: 3.3, PLS: 2.1%). After adjusting for CVD risk factors, the hazard ratios [95% confidence intervals (CI)] for CVD in the second and third tertiles of the RRR-pattern 2 were 1.76 (1.15, 2.69) and 1.55 (1.00, 2.43) vs. the first tertile (p-trend: 0.058). This pattern had high positive loadings for non-leafy vegetables, pickled vegetables, fried vegetables, and bread and high negative loadings for eggs, cakes, butter, jam-honey, red meat, poultry, fish, juice, non-fermented dairy, and fruits. Per one SD increase in PLS-pattern 3 score, the risk of CVD was 19% higher (95%CI = 3–38%). This positive association was also observed across tertiles of the pattern (p-trend: 0.032). This pattern was characterized by high intakes of leafy vegetables, non-leafy vegetables, organ meat, soft drinks, olive oil, pickled vegetables, fried vegetables, and bread and low intakes of biscuits, cakes, butter, eggs, and non-fermented dairy.ConclusionFor each of the RRR and PLS approaches, a visceral-related DP that was positively linked to CVD was identified. These two patterns had a modest correlation. The pattern generated by PLS explained more variations in food groups and offered stronger evidence of association with CVD than the RRR-derived pattern.

Geochemical data handling, using multivariate statistical methods for environmental monitoring and pollution studies

Abstract This study utilized multivariate statistics such as hierarchical cluster and principal component analyses to monitor water and stream sediments pollution. Three Principal components loadings: PC1, PC2 and PC3 were generated from water samples data yielding eigen values of 20.563, 8.477, and 7.635 respectively. PC1 explained 28.56% of the total variance with high positive loadings for EC, turbidity, Br, Cl, SO 4 2 − , Ce, Dy, Er, Eu, La, Lu, Nd, Pr, Sm, Tb, Tm, Yb, Al, Ba, Bi, Co, Co, Cs, Mn, Th, Ti, U, V and Y. PC2 explained 11.77% of the total variance with high positive loadings for Hf and high negative factor loadings for Hg. PC3 explained 10.60% of the total variance and positively loaded for P, NO3, Cd, Ge, Ni, Pb, Sn, and Zn. PC1 is related to saline waters intrusion and geological nature of the aquifer. PC2 is controlled by high field strength element (HFSE) Hofnium (Hf) due to mineralization. PC3 contributed to pollution due to anthropogenic activities caused by chemical nitrogenous and phosphate fertilizer applications, to the soil and mineralogical constituents of the aquifer rock. Four principal components were identified in stream sediments and possessed eigen values of 12.29, 5.47, 3.19 and 2.10 respectively. PC1 explained 39.65% of the total variance and had significant positive loadings for Mo, Cu, Pb, Ni, Zn, Fe, U, Th, V, Ba, Ti, Sn, Nb, Be, Sc, Li, Zr, Rb and Hf. This suggest the occurrence of heavy mineral phases such as garnet, barite, zircon and monazite in mafic and ultramafic rocks and resistive heavy minerals. PC2 accounted for 17.65% of the total variance with moderate positive loadings for Mo, Cu, As and Ba, but with moderate negative loadings for Th, La and Ba. This component shows lithogeochemical input representative of weathering and mobility of sediments related mineralization. PC3 accounted for 10.29% of the total variance with positive high loadings for Mn, Bi and Y. PC3 may be related to anthropogenic activities such as agriculture, industry and urban life in the study area. PC4 accounted for 6.78% of the total variance with positive high loading for Ta. PC4 indicates the mineralization acquired by this component.

Integration of hydrochemical, GIS, and remote-sensing data for assessment of shallow groundwater aquifers in Wadi Nisah, Central Saudi Arabia

Groundwater samples were collected in May 2015 from 23 wells distributed in the western part of Wadi Nisah, mainly used for irrigation. Calculation of saturation indices showed that the samples were generally undersaturated with respect to halite, gypsum, anhydrite, calcite, and aragonite. Groundwater facies analysis showed that most of the collected samples were dominated by Ca–Na–SO4-type water. This water type indicates rock–water interaction, mainly gypsum dissolution. The second major water type was Na–Ca–SO4. Evaporation is the major process that controls the groundwater chemistry in the study area. Principal component analysis resulted in the extraction of two principal components. All the elements analyzed showed significant positive factor loading in the first principal component (PC1) except NO3 and Pb which showed high negative loadings in the second principal component (PC2). R-mode cluster analysis identified two groups of variables. The variables in Group 1 are the result of rock–water interaction and contamination by human and agricultural activities. Variables in Group 2 represent the dissolution of evaporite minerals. The total dissolved solids’ (TDS) results demonstrated that the water samples could be classified as either brackish or freshwater. The high TDS concentration in the brackish samples could be a result of soil–water interaction. Moreover, human activities, especially those producing agricultural and household wastewater, can increase TDS in groundwater. Remote-sensing results demonstrated that the areas of agricultural and urban land use have increased with time and have contributed to groundwater pollution.

Correlations Among New Dental and Cranial Measurements

Cranial and dental anthropometry is commonly used in many areas of research, e.g., in forensicanthropology and paleoanthropology. We propose new craniometric and dental landmarks and distancesthat may have important applications in physical anthropology. Furthermore, a classical anthropometricalapproach was applied to quantify the correlation between dental and cranial measurements,which were taken on 30 Middle Ages adult crania from Sardinia (Italy).Principal components analysis was performed to explore the correlations among inter-landmark distances.The first component showed correlations between the cranial base and maxillary inter-landmarkdistances (the ‘cranial base’ system). The second component exclusively demonstrated correlationsamong maxillary and dental inter-landmark distances (the ‘oral cavity’ system). The third componentshowed positive correlations between the zygomatic and midline maxillary inter-landmark distances,and high negative loadings that include the bilateral styloid process and midline maxillary landmarks(the ‘upper cranium’ system).The inter-landmark dental distances correlate with inter-landmark cranial distances that have notbeen described previously. These data can be applied in other research and clinical areas.

Emotion regulation and mindfulness in adolescents: Conceptual and empirical connection and associations with social anxiety symptoms

Dysregulation of emotions is a risk for social anxiety symptoms, whereas dispositional mindfulness has been proposed as assisting with emotion regulation. The aim of the current study was to examine the unique associations of dysregulation and mindfulness with adolescents' social anxiety, while focusing on the conceptual overlap and the empirical connection between dysregulation and mindfulness. Participants were 336 Australian adolescents (53% girls; 12–15 years) who completed questionnaires. Dysregulation and mindfulness were moderately correlated. Factor analysis revealed two factors accounting for 59% of the variance. The first factor, active dysregulation, had high positive loadings for five dysregulation and high negative loadings for two mindfulness subscales. The second factor, passive regulation, had a high negative loading for one dysregulation and high positive loadings for three mindfulness subscales. Both active and passive composite scores had unique associations with heightened anxiety symptoms. Regression analyses of the original subscales indicated that the dysregulation subscale limited strategies, and the mindfulness subscales observing and describing were uniquely associated with anxiety; strategies and observing were associated with more symptoms, whereas describing was associated with fewer. Interventions that address dysregulation and low capacity for mindfulness may be beneficial for adolescents with heightened social anxiety symptoms.

The Dark Side of Personality: Anti-Sociality Increases Strategic Game Play

We assess the role of anti-social personality traits in explaining heterogeneity in commonly observed social preferences. We identified a personality profile that clearly reflects anti-social personality characteristics, with high positive loadings on Machiavellianism and high negative loadings on empathy, trustworthiness and agreeableness. Anti-sociality predicts decision strategies in a manner that is consistent with its name: significantly lower levels of trust and decreased trustworthiness. To identify the strategic nature of anti-social behavior in changing environments, we assessed the moderating role of personality on investor trust and trustee reciprocity in the presence relative to the absence of the investor’s option to punish. Our results show that only the anti-social personality profile is associated with specific payoff maximizing strategy shifts induced by these environmental changes: when punishment was not available to investors, we observe significantly lower levels of investor trust and trustee reciprocity, while there is a significant increase in both behaviors when punishment was available. These effects were specific for anti-sociality, as no other personality factor was associated with such a strong adjustment of decision strategies in the presence of punishment. These results demonstrate that anti-social personality characteristics are associated with strategic behavioral shifts aimed at maximizing the extraction of resources from their counterparts. The reliability of the strategic effects of anti-social personality during trust, reciprocity and punishment strongly supports the notion that self-projection underlies anti-social decision-making.

Identification of dietary patterns associated with obesity in a nationally representative survey of Canadian adults: application of a priori, hybrid, and simplified dietary pattern techniques ,

Background: Analyzing the effects of dietary patterns is an important approach for examining the complex role of nutrition in the etiology of obesity and chronic diseases.Objectives: The objectives of this study were to characterize the dietary patterns of Canadians with the use of a priori, hybrid, and simplified dietary pattern techniques, and to compare the associations of these patterns with obesity risk in individuals with and without chronic diseases (unhealthy and healthy obesity).Design: Dietary recalls from 11,748 participants (≥18 y of age) in the cross-sectional, nationally representative Canadian Community Health Survey 2.2 were used. A priori dietary pattern was characterized with the use of the previously validated 2015 Dietary Guidelines for Americans Adherence Index (DGAI). Weighted partial least squares (hybrid method) was used to derive an energy-dense (ED), high-fat (HF), low–fiber density (LFD) dietary pattern with the use of 38 food groups. The associations of derived dietary patterns with disease outcomes were then tested with the use of multinomial logistic regression.Results: An ED, HF, and LFD dietary pattern had high positive loadings for fast foods, carbonated drinks, and refined grains, and high negative loadings for whole fruits and vegetables (≥|0.17|). Food groups with a high loading were summed to form a simplified dietary pattern score. Moving from the first (healthiest) to the fourth (least healthy) quartiles of the ED, HF, and LFD pattern and the simplified dietary pattern scores was associated with increasingly elevated ORs for unhealthy obesity, with individuals in quartile 4 having an OR of 2.57 (95% CI: 1.75, 3.76) and 2.73 (95% CI: 1.88, 3.98), respectively (P-trend < 0.0001). Individuals who adhered the most to the 2015 DGAI recommendations (quartile 4) had a 53% lower OR of unhealthy obesity (P-trend < 0.0001). The associations of dietary patterns with healthy obesity and unhealthy nonobesity were weaker, albeit significant.Conclusions: Consuming an ED, HF, and LFD dietary pattern and lack of adherence to the recommendations of the 2015 DGAI were associated with a significantly higher risk of obesity with and without accompanying chronic diseases.

Characterization of Origin and Evolution of Formation Water in Buried Hill of Jizhong Depression, China, Using Multivariate Statistical Analysis of Geochemical Data

Groundwater samples from buried hill of Jizhong Depression were evaluated using two statistical analyses: hierarchical cluster analysis (HCA) and principal component analysis (PCA). The samples were classified into four clusters, C1–C4, in HCA and the hydrochemical types of C1–C4 are HCO3-Na, Cl·HCO3-Na, Cl-Na, and Cl-Na·Ca. From C1 to C2, C3, and C4, the water-rock interaction becomes increasingly intensive, and rNa/rCl gets lower while total dissolved solids and r(Cl-Na)/rMg get higher. Three components of PCA explain 86.87% of the variance. Component1 (PC1), characterized by highly positive loadings in Na+ and Cl−, is related to evaporation concentration. Component2 (PC2) is defined by highly positive loading in HCO3- and is related to influence of atmospheric water. With high positive loadings in Ca2+ and high negative loadings in Na+ and SO42-, component3 (PC3) suggests plagioclase albitization. The combination of HCA and PCA within the hydrogeological contexts allowed the division of study area into five dynamic areas. From recharge area to discharge area, the influence of atmospheric water gets weaker and water-rock interactions such as evaporation concentration and plagioclase albitization become intensive. Therefore groundwater in buried hill showed paths of hydrochemical evolution, from C1, to C2, C3, and C4. Buried hill reservoir in Jizhong Depression is mainly distributed in hydrodynamic blocking and discharge area; therefore the two regions can be the favorable areas for petroleum migration.

Identifying Alluvial fans features using multispectral image processing techniques in selected area, northern Iraq

Landsat 7 Enhanced Thematic Mapper Plus image data was used to identify and map alluvial fans features in Shaikh Ibrahim anticline northern Iraq. In the present study, an active flowchart was design to extract and determine alluvial fans using digital image processing operations and digital elevation analysis. Two image processing methods including (image transformation and image enhancement) were used. Image transformation including principal component analysis (PCA) and ratio images (RI) analysis, while image enhancement operation including false color composite images (FCC). In image transformation processing, Based on the detailed analysis of eigenvectors and eigenvalues derived from different combinations of (PCA), five (PC) images of bands (13457) have been extracted and –PC4 has relatively strong positive loading for band 5 (0.632166) and high negative loading for band 7 (-0.369417) consequently, PC4 was given effective delineation about the major alluvial fans at the southwestern footslope from Shaikh Ibrahim anticline. In ratio image analysis, A combination of (RI) based on the spectral characteristics of alluvial fans materials were selected. Image enhancement includes A false color image of the subscene was produced by assigning band (741). This color composite was found to be useful in emphasizing to the all materials of alluvial fans. Digital elevation models (DEM) were used for describing topographic features related to the alluvial fans.

Exploring Quaternary paleolake evolution and climate change in the western Qaidam Basin based on the bulk carbonate geochemistry of lake sediments

This study focuses on the concentration of major and trace elements in the diluted acetic acid-soluble fraction of SG-1 core lacustrine sediments from the western Qaidam Basin (Tibetan Plateau) in order to explore the potential of applying bulk carbonate analysis to tracing paleolake evolution and climate change. The SG-1 core sediments are considered highly suited to the exploration of the paleoenvironmental significance of bulk carbonate geochemistry, because most carbonates in the core are authigenic in origin. Based on a principal component analysis of the elemental composition of diluted acetic acid leachate, four major components with distinct characteristics have been extracted, accounting for ~80% of the total variance. The first and most important component is associated with a high positive loading of Mn, P, Y, Sc and rare earth elements (REE); the second component is characterized by a high positive loading of Ca, Sr, and U; the third component displays a high negative loading of Mg, Li, and B; and the fourth component is associated with a relatively high positive loading of Fe, V and Cr. After considering the geochemical behavior of these element assemblies during acid leaching, we have concluded that these four components contain information indicative of watershed climate conditions, carbonate precipitation, lake water salinity and iron oxide content, respectively. Reconstructions of watershed climate change and paleolake evolution using the component scores are comparable to those reconstructed from other independent proxy records, indicating a long-term trend of lake shrinkage and climatic drying since ~2.7Ma with abrupt drying events at ~2.5Ma, ~1.8Ma, ~1.2Ma and ~0.6Ma. Our results suggest that lake carbonates bear more information about watershed climate and lake evolution than expected, and that occurrences of some elements, in particular trace elements, in the diluted acetic acid leachate are not solely and necessarily linked to carbonate minerals.

Stepwise regression and principal component analyses for quantitative traits of rapeseed genotypes at different sowing dates

The present research was done to assess the best selection criteria for yield improvement in rapeseed (Brassica napus L.) using stepwise regression and principal component analyses at different sowing dates. All the traits except 1000-seed weight were significantly affected by sowing dates. The results of stepwise regression analysis revealed that seeds per pod had an important role at the first and second sowing dates, but at the third and fourth sowing dates, pods per plant and days to flowering were more important than other yield components for a seed yield prediction model. On the basis of a cumulative percent of variation, three principal components (PCs) were determined for each sowing date. The cumulative percentages of variation for three PCs at the first to fourth sowing dates were 0.97, 0.96, 0.89 and 0.95, respectively. At the first sowing date, the first principal component (PC1) had high positive and negative PC loading values for the studied traits such as days to flowering, days to the end of flowering, duration of flowering, pods per plant and harvest index. Therefore, there was high variation in these traits among the genotypes. PC2 of the first sowing date had also high PC loadings for pods on the main raceme, seeds per pod, 1000-seed weight, biological and seed yields, therefore the correlation of these traits with this PC will be high. In PC3 of the first sowing date, height, pods on the main raceme and pods per plant had the high value of PC loadings. Based on stepwise regression analysis, seeds per pod at the first and second sowing dates and days to flowering and pods per plant at the third and fourth sowing dates had an important role for improving seed yield.

卵胎生入侵种食蚊鱼的两性异形和雌性繁殖输出

PDF HTML阅读 XML下载 导出引用 引用提醒 卵胎生入侵种食蚊鱼的两性异形和雌性繁殖输出 DOI: 10.5846/stxb201412032399 作者: 作者单位: 丽水学院生态学院,丽水学院生态学院,丽水学院生态学院,丽水学院生态学院 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目(31270443);浙江省大学生科技创新活动计划(2013R429025) Sexual dimorphism and female reproductive outputs of the ovoviviparous and invasive mosquitofish Gambusia affinis Author: Affiliation: College of Ecology,Lishui University,College of Ecology,Lishui University,College of Ecology,Lishui University,College of Ecology,Lishui University Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:检测了卵胎生入侵种食蚊鱼(Gambusia affinis)繁殖期个体大小和形态特征的两性异形以及雌性繁殖输出。结果表明,繁殖期,雌性个体的数量显著大于雄性个体,雌性个体的体长显著大于雄性个体,食蚊鱼属于偏向雌性的两性异形。以体长为协变量的One-wayANCOVA及后续的Tukey's检验显示,特定体长食蚊鱼的雌性个体的头宽、眼间距、体宽和体重均显著大于雄性个体;头长和尾鳍长的两性间差异不显著。6个形态特征变量的主成分分析(Eigenvalue≥1)发现,前2个主成分共解释65.1%的变异。头宽、眼间距、体宽和体重在第一主成分有较高的正负载系数(解释45.4%变异),头长在第二主成分有较高的负负载系数(解释19.7%变异)。食蚊鱼的繁殖输出与母体个体大小的线性回归显示,窝仔数和窝仔重均与母体体长、体重呈显著的正相关;食蚊鱼的繁殖输出与母体局部特征的线性回归显示,窝仔数和窝仔重均与母体头宽、眼间距和体宽呈显著的正相关。窝仔数与后代个体的平均体长呈显著的正相关、与后代个体的平均体重相关不显著,后代个体大小与数量不发生权衡。食蚊鱼繁殖期的性别比例、个体大小和局部形态特征的两性异形受生育力选择、性选择、生态位分化、食物竞争等多种选择压力的作用,也有利于该物种种群扩张和快速入侵。 Abstract:In this study, we measured the sexual dimorphism in body size and six other mophometrical variables along with the individual fecundity in females of ovoviviparous and invasive mosquitofish Gambusia affinis, collected in Lishui (Zhejiang, eastern China), during the reproductive season. The results showed that the number of adult females was more than that of the males during the breeding season, and the body length of adult females was significantly longer than that of adult males. Therefore, G. affinis is a species with highly female-biased sexual size dimorphism. One-way analysis of variance with body length as a covariate showed significantly higher (P<0.0001) head width, interorbital width, body width, and body mass for G. affinis females than males, while no significant sexual differences were identified based on the head length or caudal fin length. A principal component analysis resolved two components (with Eigenvalues ≥ 1) from six morphometrical variables, accounting for 65.1% of variation in the original data. The first component (45.4% variance explained) had high positive loading for size-free values of head width, interorbital width, body width, and body mass; and the second component (19.7% variance explained) had high negative loading for the size-free value of head length. Analysis of unary linear regression showed that the reproductive outputs (including brood size and mass) of G. affinis positively correlated with the female body length, body mass, head width, interorbital width, and body width. Brood size positively correlated with the average body length of offspring, but there was no correlation between the brood size and the average body mass. No trade-off was identified between the size and number of offspring. Sexual dimorphism in sex ratio, body size, and local characteristics of G. affinis was influenced by a variety of selection pressure parameters, including fecundity selection, sexual selection, niche differentiation, and food competition during the breeding season. Sexual dimorphism also contributed to population expansion and rapid invasion of the species. Our results have provided some basic data for further studies on the evolution mechanisms of fish sexual dimorphism. 参考文献 相似文献 引证文献

DIFFERENTIAL ASSOCIATION OF SCHIZOTYPAL TRAITS WITH STRATEGY FORMATION, GENERAL PSYCHOPATHOLOGY AND QUALITY OF LIFE IN THE SCHIZOPHRENIA SPECTRUM: FINDINGS FROM THE PREMES STUDY

ObjectiveSchizotypy may be a forerunner of schizophrenia-spectrum disorders (SSD). In this study we examined for the first time the association between schizotypy and prefrontal function, quality of life (QoL) and...

Divergence analysis of drought tolerant Genotypes of Wheat (Triticum astivum L.)

Thirty genotypes of wheat were grown in an Alpha Lattice Design with three replications for evaluation and divergence analysis. Seeds were sown on 24 November 2011 at Regional Wheat Research Centre, Bangladesh Agricultural Research Institute, Shyampur, Rajshahi. Significant variation was observed among the genotypes and these are grouped into six clusters. Clusters III and VI were comprised of maximum number of genotypes (6) followed by clusters I, IV, and V with 5 genotypes and the minimum genotypes (3) were in cluster II. The maximum inter-cluster distance was recorded between the Cluster VI and Cluster II followed by cluster III and Cluster II, which indicates that genotypes belonging to these distant clusters could be used in hybridization programme for getting a wide spectrum of variation among the segregates. The minimum intercluster distance was found between the Cluster IV and Cluster I followed by that of Cluster V and Cluster IV. The maximum intra-cluster distance was recorded in Cluster II, consisted of three genotypes of diverse origin followed by Cluster V consisting of five genotypes which indicated that the genotypes of these clusters might have considerable diversity among themselves. While the minimum distance was computed in Cluster I composed of five genotypes which indicated that these genotypes were genetically very close to each other. Considering the eigenvalues of all principal component analysis the PC1, PC2, PC3, PC4, and PC5 with values contributed 30.78%, 20.11%, 17.75%, 10.93%, and 7.63%, respectively, of the total variation. The results revealed from the present study that the first principal component had high positive component loading from grains/spike and high negative loading from grain yield. Considering the clusters mean value, the genotype of Cluster II and VI are most divergent and maximum heterosis and wide variability in genetic architecture may be expected from the crosses between the genotypes belonged to these clusters. More specifically the cluster II could be selected for dwarf in nature, early heading and maturity and bold grain size. The genotypes from the cluster IV could be selected for maximum spikes/m2 and maximum grain yield. The positive value of both vectors for days to heading and spikes/m2 indicated that these traits had the highest contribution towards divergence among the 30 drought tolerant wheat genotypes. DOI: http://dx.doi.org/10.3329/bjar.v39i3.21982 Bangladesh J. Agril. Res. 39(3): 385-396, September 2014

鲶鱼和胡子鲶的两性异形与雌性个体生育力

PDF HTML阅读 XML下载 导出引用 引用提醒 鲶鱼和胡子鲶的两性异形与雌性个体生育力 DOI: 10.5846/stxb201306021274 作者: 作者单位: 丽水学院,丽水学院生态学院,丽水学院生态学院,丽水学院生态学院 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金癣项目（31270443，30970435）；丽水市科技计划资助项目（20110426）；浙江省大学生科技创新活动计划资助项目（2011R429008） Sexual size dimorphism and female individual fecundity of Silurus asotus and Clarias fuscus Author: Affiliation: College of Ecology,Lishui University,College of Ecology,Lishui University,College of Ecology,Lishui University,College of Ecology,Lishui University Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:检测了鲶鱼（Silurus asotus）和胡子鲶（Clarias fuscus）繁殖期18个形态特征的两性异形以及雌性个体生育力。结果表明，鲶鱼和胡子鲶雌雄性别比例均符合1：1。One-way ANOVA显示，鲶鱼雌雄个体体长差异不显著，胡子鲶雌性个体体长显著小于雄性个体（P < 0.05）。以体长为协变量的One-way ANCOVA显示，特定体长的鲶鱼雌性个体的眼间距和体高显著大于雄性个体（P < 0.05），两性间其它局部特征不存在显著的两性差异；特定体长的胡子鲶雌性个体的体高、腹鳍基前距和腹鳍臀鳍间距显著大于雄性个体，雌性个体的臀鳍基长、尾柄高和尾鳍长显著小于雄性个体（P < 0.05），两性间其它局部特征不存在显著的两性差异。Two-way ANOVA显示，胡子鲶体长显著大于鲶鱼（P < 0.05），性别及物种与性别两因素的相互作用对体长影响不显著。以体长为协变量的Two-way ANCOVA显示，胡子鲶的头长、头宽、吻长、眼间距、尾柄高、尾鳍长、背鳍基前距、背鳍基长、腹鳍基前距、腹鳍臀鳍间距、体重和去内脏体重显著大于鲶鱼，头高、体高、臀鳍基长显著小于鲶鱼（P < 0.05），物种间的其他形态特征变量差异不显著；雌性个体的体高、背鳍基前距、腹鳍基前距、腹鳍臀鳍间距显著大于雄性个体，臀鳍基长、尾柄高、尾鳍长、背鳍基长显著小于雄性个体（P < 0.05），两性间的其他形态特征变量差异不显著；物种与性别两因素的相互作用对体高、臀鳍基长、尾柄高、尾鳍长、背鳍基长和腹鳍臀鳍间距影响显著，对其余的形态特征变量影响不显著。15个形态特征变量的主成分分析（Eigenvalue ≥ 1）发现，前2个主成分共解释68.4%的变异。头宽、眼间距、尾柄高、尾鳍长、背鳍基前距、背鳍基长、腹鳍基前距和腹鳍臀鳍间距在第一主成分有较高的正负载系数，臀鳍基长在第一主成分有较高的负负载系数（解释51.2%变异）；眼后头长在第二主成分有较高的负负载系数（解释17.2%变异）。胡子鲶在第一主成分和第二主成分的分值均显著大于鲶鱼，雌雄两性的差异以及两因素的相互作用对分值的影响均不显著。实验检测的鲶鱼、胡子鲶的怀卵数量与体长和体重回归关系显著。One-way ANCOVA及矫正平均值Tukey's检验显示，特定体长的胡子鲶的产卵数量显著大于鲶鱼。性选择是胡子鲶大个体雄性形成的主要原因，同时影响与运动相关的尾部特征。生育力选择更多的影响与雌性胡子鲶较大腹腔容积相关的形态特征变异。环境因子、食物可得性和营养状况同时影响了个体大小两性异形的形成。 Abstract:We measured the sexual size dimorphism in eighteen morphological traits and female individual fecundity of Silurus asotus and Clarias fuscus collected from Lishui (Zhejiang, eastern China) in reproductive seasons. It had been found that their sex ratios were both 1:1. One-way ANOVA showed the adults of S. asotus were not sexually dimorphic in body length, while body length was significantly larger in adult males than in adult females of C. fuscus (P < 0.05). One-way ANCOVA with body length as a covariate showed that the females of S. asotus with special body length were significantly larger than the males in interorbital width and body depth (P < 0.05), while other examined morphological traits did not differ between the sexes. Furthermore, the females of C. fuscus with special body length were significantly larger than the males in body depth, pelvic fin precoxal length, and length between pelvic fin and anal fin (P < 0.05), whereas their anal fin coxal length, caudal peduncle depth and caudal fin length were significantly shorter in females than in males, and there were no significant differences between the sexes in any other of the examined morphological traits. Two-way ANOVA showed that body length of C. fuscus was significantly larger than one of S. asotus (P < 0.05), both sex and the interaction of sex and species had no effects on the body length. Two-way ANCOVA with body length as a covariate showed that head length, head width, snout length, interorbital width, caudal peduncle depth, caudal fin length, dorsal fin precoxal length, dorsal fin coxal length, length between pelvic fin and anal fin, body mass and carcass mass of C. fuscus were significantly larger than them of S. asotus, while head depth, body depth and anal fin length of C. fuscus were significantly shorter than ones of S. asotus (P < 0.05). Meanwhile, there were no significant differences in other morphological traits between them. Body depth, dorsal fin precoxal length, pelvic fin precoxal length, length between pelvic fin and anal fin were significantly larger among females than among males, while anal fin coxal length, caudal peduncle depth, caudal fin length and dorsal fin coxal length were significantly shorter among females than among males (P < 0.05). There were no significant differences in other morphological traits between the sexes. The interaction of species and sex had significant effects on body depth, anal fin coxal length, caudal peduncle depth, caudal fin length, dorsal fin coxal, length between pelvic fin and anal fin, but it had no effect on the other morphological traits. A principal component analysis resolved two components (with eigenvalues≥1) from fifteen size-free morphological variables, accounting for 68.4% of variation in the original data. The first component (51.2% variance explained) had high positive loading for size-free values of head width, interorbital width, caudal peduncle depth, caudal fin length, dorsal fin precoxal length, dorsal fin coxal length, dorsal fin coxal length, pelvic fin precoxal length, pelvic fin precoxal length, length between pelvic fin and anal fin, wherea the first component had high negative loading for size-free values of anal fin coxal length. The second component (17.2% variance explained) had high negative loading for size-free values of postorbital head length. C. fuscus had higher scores on the first and the second axes of a principal component analysis than did S. asotu, but both sex and the interaction of sex and species had no critical effect on the scores. The individual fecundity was significantly correlated with the body length and body mass in C. fuscus and S. asotus positively. One-way ANCOVA and Tukey's test showed that C. fuscus with special body length laid significantly more eggs than S. asotus. Sexual selection was the major evolutionary reasons for large males of C. fuscus, simultaneously had effects on tail traits correlated with locomotion. Fecundity selection affected the variations of morphological traits associated with abdominal cavity volume to a large extent. Environmental factors, food availability and nutritional status affected the evolution of sexual size dimorphism at the same time. 参考文献 相似文献 引证文献

Variation in morphological characteristics of Japanese fluvial sculpin related to different environmental conditions in a single river system in eastern Japan

AbstractStream fish with low mobility are often restricted to a narrow range of a stream course, and their morphological characters tend to be affected substantially by the environmental conditions of their habitat. We examined the relationships between environmental conditions and morphological characters of Japanese fluvial sculpin (Cottus pollux), a small, benthic fish with low mobility, at seven tributaries of the same river system in eastern Japan. Discriminant function analysis (DFA) indicated significant morphological differences in sculpins amongst the seven tributaries, and over 80% of individuals were classified correctly in each tributary. The strong positive correlation/loadings on the first discriminant function (DF1: 49.9% of total variation) were anterior caudal peduncle depth (0.436) and caudal peduncle truss (0.387), both of which could be regarded as an attribute of caudal peduncle depth. The second discriminant function (DF2: 16.5% of total variation) had a high negative loading for distance between the posterior first dorsal fin and anterior anal fin (−0.454), which could be regarded as an attribute of body depth. Correlation analysis indicated that sculpin tended to have a lower caudal peduncle depth under faster bottom current velocities at the tributary scale. Individuals deviating substantially from the centroid of DF2 in each tributary had a poorer body condition. Our results suggest the possibility of changes in the morphological characters of Japanese fluvial sculpin in relation to environmental conditions even at the tributary scale within the same river system.