To investigate honeybee foraging responses to toxic nectar, honey was collected from Apis cerana colonies in the Yaoan county of Yunnan Province, China, during June, when flowers of Tripterygium hypoglaucum were the main nectar source available. Pollen analysis confirmed the origin of the honey, and high-performance liquid chromatography showed the prominent component triptolide to be present at a concentration of 0.61 mug/g +/- 0.11 SD. In cage tests that used young adult worker bees, significantly more of those provided with a diet of T. hypoglaucum honey mixed with sugar powder (1:1) died within 6 d (68.3%) compared to control groups provided with normal honey mixed with sugar powder (15.8%). Honeybees were trained to visit feeders that contained honey of T. hypoglaucum (toxic honey) as the test group and honey of Vicia sativa or Elsholtzia ciliata as control groups (all honeys diluted 1:3 with water). Bees preferred the feeders with normal honey to those with toxic honey, as shown by significantly higher visiting frequencies and longer imbibition times. However, when the feeder of normal honey was removed, leaving only honey of T. hypoglaucum, the foraging bees returned to the toxic honey after a few seconds of hesitation, and both visiting frequency and imbibition time increased to values previously recorded for normal honey. Toxic honey thus became acceptable to the bees in the absence of other nectar sources.

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<b><i>Introduction:</i></b> In recent years, many studies have focused on the association between plasminogen activator inhibitor (PAI)-1 gene 4G/5G polymorphism and risk of allergic diseases, but the results have been inconclusive. <b><i>Objective:</i></b> We conducted this meta-analysis to study the exact relationship between PAI-1 polymorphism and susceptibility to allergic diseases. <b><i>Methods:</i></b> All eligible studies were determined by an electronic literature search. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of association under all of the models. <b><i>Results:</i></b> A total of 14 studies involving 2,327 cases and 2,838 controls were included in this meta-analysis. Overall, we found a significant association between PAI-1 polymorphism and risk of allergic diseases (4G/4G + 4G/5G vs. 5G/5G: OR 1.76, 95% CI 1.39–2.22, <i>p</i> &#x3c; 0.00001). In a subgroup analysis by ethnicity, we found a markedly increased risk in Asians (OR 1.62, 95% CI 1.26–2.09, <i>p</i> = 0.0002) and Caucasians (OR 1.78, 95% CI 1.26–2.52, <i>p</i> = 0.001). In addition, significant associations between PAI-1 polymorphism and risk of allergic diseases were observed in both adults (OR 1.71, 95% CI 1.23–2.38, <i>p</i> = 0.001) and children (OR 1.87, 95% CI 1.42–2.46, <i>p</i> &#x3c; 0.00001). In a subgroup analysis by different allergic diseases, a significantly increased risk was found for asthma (OR 1.78, 95% CI 1.33–2.39, <i>p</i> = 0.001) but not for rhinitis (OR 1.51, 95% CI 0.79–2.89, <i>p</i> = 0.22). <b><i>Conclusion:</i></b> This meta-analysis demonstrated that PAI-1 gene 4G/5G polymorphism was associated with an increased risk of allergic diseases.

Tropical forests are characterized by vast biomass, complex structures, and mega-biodiversity. However, the adaptation processes of these forests to seasonal water availability are less understood, especially those located in the monsoonal and mountainous regions of tropical Southeast Asia. This study used four representative tropical forests spanning from 2° N–22° N in continental Southeast Asia to address dry-condition photosynthesis at the seasonal scale. We first provided novel and reliable estimations of ecosystem photosynthesis (gross primary production; GPP) seasonality at all four sites. As expected, both evergreen and deciduous seasonal forests exhibited higher GPPs during the rainy season than during the dry season. A bimodal pattern corresponding to solar radiation occurred in the GPP of the perhumid forest. The surface conductance (Gs) was consistently lower both in the dry season and during dry spells (DSPs) than during the wet season and non-dry spells. However, this did not prevent GPP from increasing alongside increasing irradiance in the perhumid forest, suggesting that other ecosystem physiological properties, e.g., the light-saturated photosynthetic rate, must have increased, thus surpassing the effect of Gs reduction. Thus, perhumid forests could be defined as light-demanding ecosystems with regards to their seasonal dynamics. Seasonal forests are water-stressed ecosystems in the dry season, as shown by the reductions in GPP, Gs, and related ecosystem physiological properties. At all four forest sites, we observed a lack of consistent adaptive strategy to fit the water seasonality due to the diversity in leaf phenology, soil nutrient availability, root depth, and other potential factors.