First record of red cornetfish Fistularia petimba (Syngnathiformes:Fistulariidae) from Antalya and İskenderun Bays along Turkish Coasts of the Mediterranean Sea

Here, we report the first occurrence of red cornetfish Fistularia petimba in the north‐eastern Mediterranean Sea. Altogether four specimens were captured; first two in Antalya Bay on 28 October 2016 and 26 November 2016, and the remaining two in ?skenderun Bay on 21 May 2017 during the bottom trawl surveys along the Mediterranean coast of Turkey. All specimens were young and more or less uniform in size (383, 335, 419 and 453 mm standard length). The possibility that F. petimba could become a new potential invader in the Mediterranean as its congeneric F. commersonii is cautioned against.     

Description of Megastygarctides sezginii sp. nov. (Tardigrada: Arthrotardigrada: Stygarctidae) from the Turkish Black Sea coast and a key to the genus Megastygarctides

In this paper, Megastygarctides sezginii sp. nov., a new marine species from the Black Sea (Turkey), is described. Morphological and morphometric studies have revealed that M. sezginii sp. nov. is most similar to M. setoloso Morgan & O’Reilly, 1988, but differs from it through the presence of two types of fibrils, a lack of cuticle granulation, the presence of three lateral projections with fibrils, leg fibrils arranged in transverse stripes and the presence of clumps of fibrils near the clavae. In the studied environment, the new species is frequently found in summer and almost absent in winter. Additionally, a taxonomic key for all Megastygarctides species is presented.

http://zoobank.org/urn:lsid:zoobank.org:pub:53AA1D57-8700-4A18-9099-1CDDBAEB4D3A     

Evaluation of chalcones as inhibitors of glutathione S‐transferase

Glutathione S‐transferases (GSTs) are the superfamily of multifunctional detoxification isoenzymes and play an important role in cellular signaling. In the present study, potential inhibition effects of chalcones were tested against human GST. For this purpose, GST was purified from human erythrocytes with 5.381 EU?mg^?1 specific activity and 51.95% yield using a GSH–agarose affinity chromatographic method. The effects of chalcones on in vitro GST activity were tested at various concentrations. K_i constants of chalcones were found in the range of 7.76–41.93 μM. According to the results, 4‐fluorochalcone showed a better inhibitory effect compared with the other compounds. The inhibition mechanisms of 2'‐hydroxy‐4‐methoxychalcone and 4‐methoxychalcone were noncompetitive, whereas the inhibition mechanisms of 4'‐ hydroxychalcone, 4‐ fluorochalcone, and 4,4'‐ diflurochalcone were competitive.     

Methylparaben induces malformations and alterations on apoptosis,oxidant–antioxidant status,ccnd1 and myca expressions in zebrafish embryos

Methylparabens (MP) are widely used as preservatives in cosmetics, pharmacy, and food industry. Although acute toxicity studies in animals indicated that parabens are not significantly toxic, the effects of chronic exposure under sublethal doses are still unknown and the number of related studies is limited. Our aim was to evaluate the effects of MP on the development of zebrafish embryos focusing on development, locomotor activity, oxidant–antioxidant status, apoptosis, and ccnd1 and myca expressions. The expressions of ccnd1 and myca were determined by RT‐PCR. Lipid peroxidation (LPO), nitric oxide (NO), and glutathione‐S‐transferase (GST) activities were determined spectrophotometrically. Apoptosis was determined using acridine orange staining. Locomotor activity was measured using touch‐evoked movement test. MP exposure increased malformations, LPO, apoptosis, ccnd1 and myca expressions, and decreased GST activities and NO levels compared with the control group. Our findings will lead to further understanding of the mechanism of MP toxicity, and merit further research.     

Cyclic AMP Phosphodiesterase and its Inhibitor in Slime Mould Development

CYCLIC adenosine-3′,5′-monophosphate (cyclic AMP) acts as a chemotactic factor causing cell aggregation in the slime mould, Dtctyosteltum discoideum^1,2. Aggregation in this organism is the link between the growth phase and the second phase of development, in which cells cooperate and differentiate to form a multicellular fruiting body. The finding that cyclic AMP also mediates developmental functions other than chemotaxis³ suggests that regulation of cyclic AMP synthesis and destruction is important in the control of morphogenesis in D. discoideum.     

Modular Upgradability in Consumer Electronics: Economic and Environmental Implications

Modularly upgradable product designs have been advocated to offer environmental and economic advantages; however, they are not commonly used in the consumer electronics industry. In this article, we investigate the economic and environmental benefits and challenges of modular upgradability for consumer electronics. From an economic point of view, we posit that the limited adoption of modular upgradability in consumer electronics is owing to various demand‐, technology‐, and competition‐related issues. From an environmental point of view, we posit that modularly upgradable product designs may not necessarily lead to superior environmental outcomes. To reach meaningful conclusions regarding the environmental benefits of modular upgradability, one needs to understand how product architecture affects demand, production, and consumption patterns, which arise from endogenous consumer and manufacturer choices. It is also important to take into account that modular upgradability may have potentially differentiated effects in the production, consumption, and postuse phases of the lifecycle.     

刈割与施肥干扰下高寒草甸植物功能性状的构建模式

针对目前关于植物群落功能性状构建模式及其驱动因素存在的争议, 研究了33个物种10个功能性状的构建模式。研究结果显示: (1)在刈割-施肥复合梯度上, 这些功能性状主要表现为随机构建模式, 发生随机性和确定性构建的样方比例分别为82.7%和17.3%; (2)在10个功能性状中, 生长型、生活周期、单株地上干质量、叶面积和叶干质量5个功能性状为随机构建模式, 不受试验处理和群落特征(地上净初级生产力、刈割生物量损失、群落高度)变化的影响。植物倾斜度、繁殖方式、固氮性、株高和比叶面积5个功能性状的构建模式与试验处理或群落特征变化有关, 表现出趋同或趋异构建响应。其中, 植物倾斜度和比叶面积的构建模式仅受群落特征影响, 而固氮性、繁殖方式和株高3个性状的构建模式同时还受刈割或施肥处理的影响, 其构建模式因功能性状而异; (3)群落的生物量损失和地上净初级生产力是解释植物功能性状构建模式变化较理想的群落特征; (4)刈割和施肥处理对株高的构建模式具有相反效应, 而刈割和施肥的交互作用对其无显著影响。上述结果说明该研究群落植物功能性状的构建存在不同模式, 以随机构建模式为主, 确定性构建模式居次要地位。确定性构建模式与试验处理和群落特征变化有关, 而且是性状依赖的。相反选择力对趋同和趋异构建模式的平衡效应能引起功能性状发生随机构建。     

Light capture efficiency decreases with increasing tree age and size in the southern hemisphere gymnosperm Agathis australis

We investigated leaf and shoot architecture in relation to growth irradiance (Q_int) in young and mature trees of a New Zealand native gymnosperm Agathis australis (D. Don) Lindl. to determine tree size-dependent and age-dependent controls on light interception efficiency. A binomial 3-D turbid medium model was constructed to distinguish between differences in shoot light interception efficiency due to variations in leaf area density, angular distribution and leaf aggregation. Because of the positive effect of light on leaf dry mass per area (M_A), nitrogen content per area (N_A) increased with increasing irradiance in both young and mature trees. At a common irradiance, N_A, M_A and the components of M_A, density and thickness, were larger in mature trees, indicating a greater accumulation of photosynthetic biomass per unit area, but also a larger fraction of support biomass in older trees. In both young and mature trees, shoot inclination angle relative to horizontal, and leaf number per unit stem length decreased, and silhouette to total leaf area ratio (S_S) increased with decreasing irradiance, demonstrating more efficient light harvesting in low light. The shoots of young trees were more horizontal and less densely leafed with a larger S_S than those of mature trees, signifying greater light interception efficiency in young plants. Superior light harvesting in young trees resulted from more planar leaf arrangement and less clumped foliage. These results suggest that the age-dependent and/or size-dependent decreases in stand productivity may partly result from reduced light interception efficiency in larger mature relative to smaller and younger plants.