Monitoring with lichens – Conductivity methods assess salt and heavy metal damage more efficiently than chlorophyll fluorescence

In the lab, we exposed three foliose lichen species, Lobaria pulmonaria, Parmelia sulcata and Xanthoria aureola, to 0, 0.01, 0.2, and 0.6 M NaCl in combinations with copper and zinc (0, 10, 100, 500 μM). High salt concentrations adversely affected the lichen membrane integrity as measured by conductivity methods, whereas the potential photosystem II efficiency (Fv/Fm) was tolerant. High light was necessary to reduce Fv/Fm in thalli exposed to salt, whereas high light did not aggravate the conductivity. The seashore species X. aureola was much more resistant to salt than the old forest species L. pulmonaria. With respect to Cu and Zn, used concentrations had no (P. sulcata, X. aureola) or small (L. pulmonaria) effects on Fv/Fm. However, both heavy metals substantially increased conductivity in all species, consistent with membrane damage. Thus, the conductivity method detected high salt, high copper and high zinc stress much more efficiently than did the chlorophyll fluorescence method. This suggests that membrane integrity of the mycobiont is more sensitive to salt and heavy metal stress than potential photosystem II efficiency of its autotrophic partners.     

Restoration scenario planning at a Spanish quarry can be informed by assessing ecosystem services

We carried out an ecosystem service (ES) assessment at Soto de Pajares, a 400 ha active gravel quarry site located close to protected areas in the southeast of the Community of Madrid, Spain. The currently approved restoration plan is for quarry‐made excavations to be restored back to agricultural land. However, the site has been identified as being important for nature, so different restoration strategies should be considered. To better understand how these compare in terms of ES provision, which had not previously been done at mineral extraction sites in Spain, we used an established toolkit: the Toolkit for Ecosystem Service Site‐based Assessments (TESSA). We compared the agriculture‐focused restoration plan and two nature‐focused alternative scenarios, one without public access (conservation scenario) and the other with public access (compromise scenario). Monetary estimations of the value of agricultural production, climate change mitigation, and recreation were calculated in three scenarios. Results indicated that the compromise scenario provided the greatest annual value (€91,409), mainly due to its potential visitors, surpassing both agricultural (€68,504) and conservation (€48,556) scenarios. Considering the higher costs associated with restoring sites to agricultural production, nature conservation may be an attractive option for extraction companies. The use of TESSA at this site has provided valuable information to quarry managers to help guide their decision‐making.     

The Cap-Snatching SFTSV Endonuclease Domain Is an Antiviral Target

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婴幼儿喂养指数法评价6~23月龄婴幼儿喂养状况的临床价值

摘要 目的：探讨婴幼儿喂养指数法（ICFI）评价6~23月龄婴幼儿的喂养状况的临床价值。方法：于2015年6月至2016年2月，按照多阶段分层整群随机抽样的方法，抽取1418例6~23月龄婴幼儿作为调查对象。根据世界卫生组织（WHO）喂养建议建立喂养指数体系（包括母乳喂养、奶瓶喂养、膳食多样性、食物频率和喂养频率），进行ICFI评分。结果：本次共调查1418例婴幼儿，男766例（54.02 %），女652例（45.98 %）。6~8月龄组482例（33.99 %），9~11月龄组457例（32.23 %），12~23月龄组479例（33.78 %）。母乳喂养率为45.06 %，随月龄增加母乳喂养率降低（x²=234.486，P<0.05）。奶瓶喂养率为74.75 %，随月龄增加奶瓶喂养率升高（x²=75.671，P<0.05）。膳食多样性总满分率为67.42 %，满分率随月龄增加而增加（x²=154.146，P<0.05）。6~8、9~11月龄食物频率总满分率由高到低依次为谷类、蔬菜/水果、蛋/鱼/禽肉类、豆类及其制品、畜肉类；12~23月龄依次为奶类及其制品、蔬菜/水果、蛋/鱼/禽肉类、畜肉类、豆类及其制品。三个月龄组间食物频率评分随月龄增加而增加（F=1240.819，P<0.05）。喂养频率满分率为41.11 %（583/1418），随月龄增加而降低（x²=149.05，P<0.05）。结论：ICFI可客观地反映婴幼儿的喂养状况，目前6~23月龄婴幼儿喂养状况不容乐观，喂养状况随着月龄减小而变差。     

Flight loss linked to faster molecular evolution in insects

The loss of flight ability has occurred thousands of times independently during insect evolution. Flight loss may be linked to higher molecular evolutionary rates because of reductions in effective population sizes (N_e) and relaxed selective constraints. Reduced dispersal ability increases population subdivision, may decrease geographical range size and increases (sub)population extinction risk, thus leading to an expected reduction in N_e. Additionally, flight loss in birds has been linked to higher molecular rates of energy-related genes, probably owing to relaxed selective constraints on energy metabolism. We tested for an association between insect flight loss and molecular rates through comparative analysis in 49 phylogenetically independent transitions spanning multiple taxa, including moths, flies, beetles, mayflies, stick insects, stoneflies, scorpionflies and caddisflies, using available nuclear and mitochondrial protein-coding DNA sequences. We estimated the rate of molecular evolution of flightless (FL) and related flight-capable lineages by ratios of non-synonymous-to-synonymous substitutions (dN/dS) and overall substitution rates (OSRs). Across multiple instances of flight loss, we show a significant pattern of higher dN/dS ratios and OSRs in FL lineages in mitochondrial but not nuclear genes. These patterns may be explained by relaxed selective constraints in FL ectotherms relating to energy metabolism, possibly in combination with reduced N_e.     

Forest floor photosynthesis and respiration in a drained peatland forest in southern Finland

Background: Although forest floor forms a large biomass pool in forested peatlands, little is known about its role in ecosystem carbon (C) dynamics.

Aim: We aimed to quantify forest floor photosynthesis (P _FF) and respiration (R _FF) as a part of overall C dynamics in a drained peatland forest in southern Finland.

Methods: We measured net forest floor CO₂ exchange with closed chambers and reconstructed seasonal CO₂ exchange in the prevailing plant communities.

Results: The vegetation was a mosaic of plant communities that differed in CO₂ exchange dynamics. The reconstructed growing season P _FF was highest in the Sphagnum community and lowest in the feather moss communities. On the contrary, R _FF was highest in the feather moss communities and lowest in the Sphagnum community. CO₂ assimilated by the forest floor was 20–30% of the total CO₂ assimilated by the forest. The forest floor was a net CO₂ source to the atmosphere, because respiration from ground vegetation, tree roots and decomposition of soil organic matter exceeded the photosynthesis of ground vegetation.

Conclusions: Tree stand dominates C fluxes in drained peatland forests. However, forest floor vegetation can have a noticeable role in the C cycle of peatlands drained for forestry. Similarly to natural mires, Sphagnum moss-dominated communities were the most efficient assimilators of C.     

Advances in increment coring system for large tropical trees with high wood densities

Incremental coring of trees is the key method used in non-destructive dendrochronological sampling. Despite the advances in developing such methods, the sampling of large, high-density trees still poses a challenge in remote tropical forests. Manually operated incremental drills, while easy to transport across difficult terrain, limit sample size and can often get damaged in the sampling process, especially when trees have wood densities above 0.8 g/cm³. Here, we discuss the existing available alternatives and present an up-to-date incremental coring system composed of a borer coupled to a hand-held drilling machine and a support attached to the tree which can collect incremental cores of 1.5 mm in diameter and over 1.0 m in length. The support ensures stability for the drill throughout the sampling process. This system is relatively lightweight and portable, offering field flexibility and suitability for sampling in remote locations. It provides a core sample of an appropriate diameter and amount for carrying out ring-width measurements, stable isotope and radiocarbon analyses on some of the large, older trees which are now being found in the tropics. We expect that this methodology will broaden the possibilities in the now-blossoming sub-field of tropical dendrochronology.     

Evaluation of total contents of Al,As, Ca,Cd, Fe,K, Mg,Ni, Pb,Zn and their fractions leached to the infusions of different tea samples. A multivariate study

ABSTRACT

Total aluminum, arsenic, calcium, cadmium, iron, lead, potassium, magnesium, nickel and zinc were determined in black tea by electro thermal atomic absorption spectrometry after ultrasonic assisted pseudo-digestion with mixture of acid and oxidant. All the metals were also determined in the tea infusions in order to know the percentage of each element leached into the liquor. A conventional acid digestion on electric hot plate was used to obtain total metals under study for comparative purpose. Analytical results for Al, As, Ca, Cd, Fe, K, Mg, Ni, Pb and Zn obtained by ultrasound assisted pseudodigestion, and conventional wet digestion methods showed a good agreement, thus indicating the possibility of using ultrasonic assisted digestion sample preparation instead of intensive treatments inherent with the acid digestion methods on electric hot plate. The validity and accuracy of both procedures were checked by using certified sample of NIES No. 7 (Tea Leaves). Non significant differences were observed for P>0.05 when comparing the values obtained by both methods (paired t-test).

Principal component analysis (PCA) was applied in order to determine the different amount of metals as main sources of variability in the data sets and to establish the relation between samples (branded and nonbranded tea samples) and micronutrient, trace and toxic metals (variables). Hierarchical cluster analysis (HCA) was used to explore the different branded and nonbranded tea samples grouping according to the essential and toxic metals as additional information to the out put obtained by PCA.     

Phosphoproteome Profiling of the Receptor Tyrosine Kinase MuSK Identifies Tyrosine Phosphorylation of Rab GTPases

Muscle-specific receptor tyrosine kinase (MuSK) agonist antibodies were developed 2 decades ago to explore the benefits of receptor activation at the neuromuscular junction. Unlike agrin, the endogenous agonist of MuSK, agonist antibodies function independently of its coreceptor low-density lipoprotein receptor–related protein 4 to delay the onset of muscle denervation in mouse models of ALS. Here, we performed dose–response and time-course experiments on myotubes to systematically compare site-specific phosphorylation downstream of each agonist. Remarkably, both agonists elicited similar intracellular responses at known and newly identified MuSK signaling components. Among these was inducible tyrosine phosphorylation of multiple Rab GTPases that was blocked by MuSK inhibition. Importantly, mutation of this site in Rab10 disrupts association with its effector proteins, molecule interacting with CasL 1/3. Together, these data provide in-depth characterization of MuSK signaling, describe two novel MuSK inhibitors, and expose phosphorylation of Rab GTPases downstream of receptor tyrosine kinase activation in myotubes.     

Isolation and Characterization of Two Novel Nematicidal Depsipeptides from an Imperfect Fungus,Strain D1084

Two novel nematicidal cyclodepsipeptides, designated bursaphelocides A and B, were isolated from the culture filtrate of an imperfect fungus, strain D1084, belonging to Mycelia sterilia. Bursaphelocide A (1), containing 2-hydroxy-3-methylpentanoic acid, proline, isoleucine, N-methylalanine, N-methylvaline, and β-alanine in sequence, and bursaphelocide B (2), comprising 4-methylproline instead of proline in 1, are novel 2-hydroxy-3-methylpentanoic acid analogues of insecticidal destruxins.