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To determine the effect of tree canopy composition on understory species abundance, three-hundred 2 m × 2-m quadrats from 30 high-latitude boreal forest stands were sampled. In addition, all trees within a 3mradius of each quadrat center and ≥1 m tall were also measured for height, basal diameter, and canopy width (n = 3130). Stands were 33–178 years old, with canopies of Populus tremuloides (trembling aspen) and Picea spp. (spruce) in varying proportions. Arctostaphylos uva-ursi, Calamagrostis purpurascens, Chamerion angustifolium, Shepherdia canadensis, and Hylocomium splendens were the most frequent understory species among quadrats. Scatterplots of P. tremuloides and individual vascular understory species cover values lacked bivariate trends, but the understory species had distinct maxima that ranged from 20 to 90%. A moderately strong correlation (r = 0.52, P <0.001) occurred between P. tremuloides canopy and total vascular understory plant covers, but weak individual species correlations (r = 0.22–0.35, P <0.001), suggested understory species variation was primarily determined by factors other than the amount of immediately overhead canopy cover. Canonical correlation analysis (R = 0.82, P <0.001) indicated that greater vascular understory plant cover occurred when forest stands consisted of P. tremuloides with large canopies and large basal diameters, and lacked Picea. Maximum cover for vascular understory species declined when Picea cover exceeded 7–10%. In combination, P. tremuloides stem densities or a metric based on summed canopy areas converted to a diameter value (canopy-area diameter), and the vertical silhouette area of Picea canopies (canopy profile area), as independent linear regression variables, explained ∼79% of the variance in total vascular understory plant cover. Several Picea basal areaderived metrics were strongly and positively associated with increasing H. splendens cover, but canopy profile area was more informative. Populus tremuloides canopy area and Picea canopy profile area, as indicators of shading, may be important determinants of vascular understory vegetation abundance in stands where solar radiation enters at angles of up to 52° during the summer.

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Abstract

Plant community diversity is a major research focus in community ecology. The relationship between diversity patterns and different diversity indices is important for developing and improving biodiversity protection. In order to fully understand multi-dimensional diversity patterns of the subalpine meadow on Heyeping peak of Luya Mountain, we used a systematic sampling method and set 150 1 m × 1 m plots in June of 2018. Based on an analysis of the subalpine meadow community on Heyeping peak, we measured multiple diversity indices, carried out a correlation analysis between diversity and environmental factors, and compared correlations among different diversity indices. The goal was to clarify the ecological mechanisms and variation among various diversity indices and environmental factors. The main results were as follows: (1) The species diversity distribution was uniform, the taxonomic level was narrow, functional differences were small, and different pedigree structures were present in each plot. (2) A stable correlation between pedigree diversity index (PD) and species diversity index indicated niche conservativism; the net relatedness index (NRI) of community lineage structure was significantly correlated with the nearest species taxon index (NTI), species richness, and evenness index, indicating that plant community composition in the study area is mainly affected by habitat filtration. (3) The average taxonomic distinctness index (Λ+) and the average taxonomic distinctness index (Λ+) had a stable correlation; only the functional richness index (FRic) and Patrick species richness index were closely related. (4) Among the selected environmental factors, only the forest line had a stable correlation with species diversity index and PD and showed a negative correlation change, indicating an “edge effect” distribution of species diversity in the study area. In summary, the forest line was the key factor affecting the distribution of species diversity in the study area and the species relationships within the community. This work was supported by the National Natural Science Foundation of China (31400358).

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Abstract  

One of the most critical elements of a performance evaluation (PE) program for radioactivity measurements is the traceability of the PE materials to the national standards. The requirements and criteria for the production of traceable environmental and radiobioassay PE materials have been defined by ANSI N42.22 and ANSI N13.30 standards. It is important to note that use of traceable source materials does not necessarily ensure the traceability of subsequently derived PE materials unless verification measurements exist in conjunction with the preparation processes. This paper describes the protocol currently used by NIST for the preparation and verification of air filter, acidified water, spiked soil, synthetic urine, and synthetic fecal PE materials for low-level radioactivity measurements. The process involves gravimetric dilutions and mixing of primary radionuclide NIST Standard Reference Materials (SRMs), addition of the derived master solution to sample matrices, and subsequent verification measurements. Several gamma-emitters were used to trace the gravimetric dilutions and spike addition through an unbroken chain of gamma comparison measurements. The massic activities of alpha- and beta-emitters in the diluted solutions and PE samples were also measured by radiochemical methods and compared with their gravimetric values. A correlation analysis demonstrated that the gamma emitters quantitatively followed 90Sr, 238U, 238Pu, and 241Am throughout the dilution and spiking and can be used as effective process monitors. The statistical results from t-tests, box plots, and normal probability tests suggested that traceability of radionuclides in the PE materials to their primary standards can be verified to within 1%, with an overall precision better than 2% (1s).

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Absztrakt

A tudományos narratív pszichológia módszere, amint az a jelen folyóiratszámban közölt tanulmányokból is kitűnik, a tartalomelemzés (László, Ehmann, Péley, Pólya, 2000; Ehmann, 2002; László, 2005; 2008a). Az elbeszélésekkel foglalkozó kutatások, amiket gyűjtőnéven narratív pszichológiának nevezünk, s amelynek irányzataitól saját felfogásunkat a „tudományos” jelzővel különböztetjük meg, többnyire ugyancsak a tartalomelemzés módszerét alkalmazzák. Ez a kettősség félreértéseket szülhet, ezért ebben a tanulmányban kísérletet teszünk arra, hogy a narratív pszichológiai tartalomelemzés sajátosságait a tartalomelemzés más formáihoz képest meghatározzuk. Más oldalról egy ilyen fogalmi és módszertani tisztázási kísérlet azért is időszerű, mert a tartalomelemzési módszerekkel foglalkozó kutatók nehezen értik meg, hogy miben rejlik az az elméleti és módszertani újítás, ami a narratív pszichológiai tartalomelemzést a tartalomelemzés más formáitól megkülönbözteti és egy új pszichológiai megközelítés alapvető eljárásává teszi. Tekintettel arra, hogy napjainkban a tartalomelemzés különböző formáit, így a narratív pszichológiai tartalomelemzést is számítógépes támogatással végzik, a tartalomelemzés formáinak különböző nyelvtechnológiai igényeire és lehetőségeire is kitérünk. Azt sem kerülhetjük meg, hogy a tartalomelemzés különböző formái mögött meghúzódó ismeretelméleti előfeltevésekkel foglalkozzunk.

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The gluten proteins of 15 winter wheat cultivars grown in eastern Croatia were studied for their contribution to the bread-making quality. Composition of high-molecular-weight glutenin subunits (HMW-GS) was analyzed by SDS-PAGE, while the quantity of gluten proteins was determined by combined extraction/RP-HPLC procedure. The results of the linear correlation analysis carried out on the particular gluten proteins and technological properties showed that the amount of total gluten content highly correlates with protein content. Among gluten proteins, the glutenins showed higher correlation with protein content, with pronounced influence of HMW-GS, than gliadins. Wet gluten content was significantly correlated to total gliadin quantity. Gluten index as gluten quality parameter was positively influenced by total glutenins and low-molecular-weight glutenin subunits (LMW-GS), and negatively, by the ratios of gliadin to glutenin (Gli/Glu), whereas the amount of gliadins was not important. Dough development time was strongly correlated with total gluten content, total glutenins and the Gli/Glu ratio. Dough mixing resistance was strongly affected by total glutenin content with pronounced influence of HMW-GS. Degree of dough softening is mainly negative influenced by total glutenins and ratio of Gli/Glu. Farinograph quality number as flour quality index was highly positively correlated with total glutenins, with emphasized influence of HMW-GS. The Gli/Glu ratio had the highest influence on dough maximum resistance. Dough extensibility showed moderate correlation with total gliadins. The results of the linear correlation indicated that loaves volumes were significantly influenced by total gluten proteins, HMW-GS and LMW-GS.

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Journal of Behavioral Addictions
Authors: Fatih Canan, Servet Karaca, Melike Düzgün, Ayşe Merve Erdem, Esranur Karaçaylı, Nur Begüm Topan, Sang-Kyu Lee, Zu Wei Zhai, Murat Kuloğlu, and Marc N. Potenza

Background and aims

The ratio of the second and fourth fingers (2D:4D ratio) is a sexually dimorphic trait, with men tending to have lower values than women. This ratio has been related to prenatal testosterone concentrations and addictive behaviors including problematic video-gaming. We aimed to investigate the possible association between 2D:4D ratios and Internet addiction and whether such a relationship would be independent of impulsivity.

Methods

A total of 652 university students (369 women, 283 men), aged 17–27 years, were enrolled in the study. Problematic and pathological Internet use (PPIU) was assessed using the Internet Addiction Test (IAT). The participants also completed the Barratt Impulsiveness Scale (version 11; BIS-11) and had their 2D:4D ratios measured.

Results

2D:4D ratios were not significantly different in women with PPIU and in those with adaptive Internet use (AIU). Men with PPIU exhibited lower 2D:4D ratios on both hands when compared with those with AIU. Correlation analysis revealed that 2D:4D ratios on both hands were negatively correlated with IAT scores among men, but not among women. The multiple linear regression analysis revealed that age, duration of weekly Internet use, impulsiveness, and 2D:4D ratios on the right hand were independently associated with IAT scores among men, and impulsivity did not mediate the relationship between 2D:4D ratios and PPIU.

Conclusions

For men, 2D:4D ratios on the right hand were inversely correlated with Internet addiction severity even after controlling for individual differences in impulsivity. These findings suggest that high prenatal testosterone levels may contribute to the occurrence of PPIU among men.

Open access

Hydroxycitric acid made the genus Garcinia economically important. Genetic and chemical diversity has been studied in Garcinia species using molecular markers, HCA and antioxidant activity. Nine species were collected and screened for molecular diversity and six were subjected to analyse antioxidant and HCA content and its interspecies variability. A total of 129, 125 and 89 bands with polymorphism of 78.74%, 78.4% and 93.36% were obtained using ISSR, RAPD and EST-SSR, respectively. The average PIC value obtained with ISSR, RAPD and EST-SSR markers was 0.9161, 0.9440 and 0.8903, respectively. Determined HCA content by HILIC-HPLC system using 0.1% orthophosphoric acid and acetonitrile (30:70) as mobile phase in fruit powder of various Garcinia species was found to be significantly different. G. gummi-gutta, G. indica and G. xanthochymus are rich of HCA containing 12.44±1.04%, 7.92±0.83% and 6.3±0.286%, respectively. G. morella, G. talbotii and G. celebica contained very negligible amount of HCA, 0.023±0.012%, 0.083±0.034% and 0.34±0.013%, correspondingly. G. talbotii showed high antioxidant capacity (95.40±0.720). Below that G. indica and G. xanthochymus were showing significant amount of total phenols (1.23±0.015 and 1.07±0.008), flavonoids (11.17±0.075 and 12.35±0.219) and antioxidant activity (90.73±0.976 and 91.37±0.854). Correlation analysis found significant association between molecular and chemical variation indicating influence of genetic background on the observed HCA and antioxidant profiles. The conducted analysis showed the most distinct species at the genetic and chemical levels were G. gummi-gutta, G. indica and G. xanthochymus. This study signifies the utility of molecular and chemical fingerprints for commercial exploitation of HCA from Garcinia species.

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Journal of Behavioral Addictions
Authors: Josephine Savard, Tatja Hirvikoski, Katarina Görts Öberg, Cecilia Dhejne, Christoffer Rahm, and Jussi Jokinen

Abstract

Background and aims

Impulsivity is regarded as a risk factor for sexual crime reoffending, and a suggested core feature in Compulsive Sexual Behavior Disorder. The aim of this study was to explore clinical (e.g. neurodevelopmental disorders), behavioral and neurocognitive dimensions of impulsivity in disorders of problematic sexuality, and the possible correlation between sexual compulsivity and impulsivity.

Methods

Men with Compulsive Sexual Behavior Disorder (n = 20), and Pedophilic Disorder (n = 55), enrolled in two separate drug trials in a specialized Swedish sexual medicine outpatient clinic, as well as healthy male controls (n = 57) were assessed with the Hypersexual Behavior Inventory (HBI) for sexual compulsivity, and with the Barratt Impulsiveness Scale (BIS) and Connors’ Continuous Performance Test-II (CPT-II) for impulsivity. Psychiatric comorbidity information was extracted from interviews and patient case files.

Results

Approximately a quarter of the clinical groups had Attention-Deficit/Hyperactivity Disorder (ADHD) or Autism Spectrum Disorder. Both clinical groups reported more compulsive sexuality (r = 0.73−0.75) and attentional impulsivity (r = 0.36−0.38) than controls (P < 0.05). Based on results on univariate correlation analysis, BIS attentional score, ADHD, and Commissions T-score from CPT-II were entered in a multiple linear regression model, which accounted for 15% of the variance in HBI score (P < 0.0001). BIS attentional score was the only independent positive predictor of HBI (P = 0.001).

Discussion

Self-rated attentional impulsivity is an important associated factor of compulsive sexuality, even after controlling for ADHD. Psychiatric comorbidity and compulsive sexuality are common in Pedophilic Disorder.

Conclusion

Neurodevelopmental disorders and attentional impulsivity – including suitable interventions – should be further investigated in both disorders.

Open access

Background and aims

This study focuses on the use of popular information and communication technologies (ICTs) by adolescents: the Internet, mobile phones, and video games. The relationship of ICT use and experiential avoidance (EA), a construct that has emerged as underlying and transdiagnostic to a wide variety of psychological problems, including behavioral addictions, is examined. EA refers to a self-regulatory strategy involving efforts to control or escape from negative stimuli such as thoughts, feelings, or sensations that generate strong distress. This strategy, which may be adaptive in the short term, is problematic if it becomes an inflexible pattern. Thus, the aim of this study was to explore whether EA patterns were associated with addictive or problematic use of ICT in adolescents.

Methods

A total of 317 students of the Spanish southeast between 12 and 18 years old were recruited to complete a questionnaire that included questions about general use of each ICTs, an experiential avoidance questionnaire, a brief inventory of the Big Five personality traits, and specific questionnaires on problematic use of the Internet, mobile phones, and video games.

Results

Correlation analysis and linear regression showed that EA largely explained results regarding the addictive use of the Internet, mobile phones, and video games, but not in the same way. As regards gender, boys showed a more problematic use of video games than girls. Concerning personality factors, conscientiousness was related to all addictive behaviors.

Discussion and conclusions

We conclude that EA is an important construct that should be considered in future models that attempt to explain addictive behaviors.

Open access

References Chen Jia-Hai ( 2012 ). Correlation Analysis of Logistics Industry Development and Regional Economy — A case study on

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