Seasonal variation of the forewing in polyvoltine whites <Emphasis Type="Italic">Pieris rapae</Emphasis> L. and <Emphasis Type="Italic">P. napi</Emphasis> L. (Lepidoptera: Pieridae) in the forest-steppe zone of the Southern Urals

The seasonal variation of forewing size and shape was analyzed in adults of different seasonal generations of two polyvoltine species of whites: Pieris rapae and P. napi (Lepidoptera: Pieridae). Particular morphological features of the forewing are characteristic of each seasonal generation of adults independently of their sex and species. Adults of the spring generations have the smallest wings, elongate and pointed. Adults of the summer generation have the largest, broad and rounded wings over the entire summer season. Adults of the autumn generation have wings similar in shape and size to those of the summer generation, but somewhat smaller and more elongate. Differences between seasonal generations in forewing shape are linked to differences between adults of each generation in adaptation to dispersal.     

Effects of climate change on the distribution of endemic <Emphasis Type="Italic">Ferula xylorhachis</Emphasis> Rech.f. (Apiaceae: Scandiceae) in Iran: Predictions from ecological niche models

Ferula xylorhachis Rech.f. is an endemic plant species belonging to the Apiaceae family and distributed in northeastern Iran. In the present study, we attempted to determine the factors with the greatest effects on the distribution of this species and to determine suitable regions for it based on current and future conditions. The Maximum Entropy method was used in the present study and the results indicated that the Mean Temperature of Wettest Quarter (48.2%), Precipitation of Wettest Quarter (49.1%), and Precipitation of Wettest Month (61.4%) are the most important factors in the current and in two future periods (2040 and 2070). The models suggest that suitable regions for the presence of this species will change over time and that the species will encounter limitations through changes such as moisture reduction. According to the A1B scenario, increases in greenhouse gases such as CO₂ and CH₄ will have direct effects on future precipitation and temperature and these factors will be important in determining species dispersion. Evaluation of important habitat factors using normal ecological methods will help in developing the best conservation programs in the future. Introducing species to new regions will help to protect them from the extinction risk caused by climate change.     

Impact of cigarette smoking on volatile organic compound (VOC) blood levels in the U.S. population: NHANES 2003-2004

The impact of cigarette smoking on volatile organic compound (VOC) blood levels is studied using 2003-2004 National Health and Nutrition Examination Survey (NHANES) data. Cigarette smoke exposure is shown to be a predominant source of benzene, toluene, ethylbenzene, xylenes and styrene (BTEXS) measured in blood as determined by (1) differences in central tendency and interquartile VOC blood levels between daily smokers [≥1 cigarette per day (CPD)] and less-than-daily smokers, (2) correlation among BTEXS and the 2,5-dimethylfuran (2,5-DMF) smoking biomarker in the blood of daily smokers, and (3) regression modeling of BTEXS blood levels versus categorized CPD. Smoking status was determined by 2,5-DMF blood level using a cutpoint of 0.014 ng/ml estimated by regression modeling of the weighted data and confirmed with receiver operator curve (ROC) analysis. The BTEXS blood levels among daily smokers were moderately-to-strongly correlated with 2,5-DMF blood levels (correlation coefficient, r, ranging from 0.46 to 0.92). Linear regression of the geometric mean BTEXS blood levels versus categorized CPD showed clear dose-response relationship (correlation of determination, R(2), ranging from 0.81 to 0.98). Furthermore, the pattern of VOCs in blood of smokers is similar to that reported in mainstream cigarette smoke. These results show that cigarette smoking is a primary source of benzene, toluene and styrene and an important source of ethylbenzene and xylene exposure for the U.S. population, as well as the necessity of determining smoking status and factors affecting dose (e.g., CPD, time since last cigarette) in assessments involving BTEXS exposure.