Ecologically heterogeneous populations of the invasive ant Wasmannia auropunctata within its native and introduced ranges

Abstract 1. The biology of most invasive species in their native geographical areas remains largely unknown. Such studies are, however, crucial in shedding light on the ecological and evolutionary processes underlying biological invasions. 2. The present study focuses on the little fire ant Wasmannia auropunctata, a species native to Central and South America that has been widely introduced and which has become invasive throughout the tropics. We characterise and compare several ecological traits of native populations in French Guiana with those in one of its introduced ranges, New Caledonia. 3. We found ecologically heterogeneous populations of W. auropunctata coexisting in the species’ native geographical area. First, we found populations restricted to naturally perturbed areas (particularly floodplains) within the primary forest, and absent from the surrounding forest areas. These populations were characterised by low nest and worker densities. Second, we found dominant populations in recent anthropogenic areas (e.g. secondary forest or forest edge along road) characterised by high nest and worker densities, and associated with low ant species richness. The local dominance of W. auropunctata in such areas can be due to the displacement of other species (cause) or the filling‐up of empty habitats unsuitable to other ants (effect). With respect to their demographic features and ant species richness, the populations of native anthropogenic habitats were to a large extent similar to the invasive populations introduced into remote areas. 4. The results point to the need for greater research efforts to better understand the ecological and demographic features of invasive species within their native ranges.     

Can the emergence of pine Diplodia shoot blight in France be explained by changes in pathogen pressure linked to climate change?

Sphaeropsis shoot blight, caused by Diplodia pinea and Diplodia scrobiculata, damage conifers throughout the world. In France, the first disease outbreaks were reported during the 1990s. The factors associated with the pathogen presence in stands and the relationship between pathogen and disease distributions were analysed in order to understand the Sphaeropsis emergence. Eighty‐two stands of Pinus nigra, Pinus sylvestris, Pinus pinaster and Pinus radiata were visited. Cones were collected on the ground to assess the pathogen frequency. Diplodia spp were isolated and determined by a species‐specific PCR test. The role of potential explaining factors of D. pinea prevalence on cones was analysed by logistic regression. D. pinea was the dominant species in visited stands. The main factors influencing the pathogen presence selected in the models were host species (the pathogen being less frequent on P. pinaster than on P. nigra and P. sylvestris cones), winter temperature and summer rain, which were both positively correlated with cone colonization. The climate became more favourable to D. pinea presence within the last 15 years compared with the previous 30‐year period. By contrast, future climatic changes over the next 40 years should have far less impact on the pathogen presence.     

Predictive modeling of β-carotene accumulation by Dunaliella salina as a function of pH,NaCI, and irradiance

Predictive modeling of β-carotene accumulation by Dunaliella salina as a function of NaCI, pH, and irradiance was studied. Modified Logistic, Gompertz, Schnute, Richards, and Stannard models were fitted to describe β-carotene accumulation by the alga under various environmental conditions. Lag time (λ, days), maximum accumulation (A, pg/cell), and the maximum production rate (μ, 1/day) for β-carotene accumulation were calculated by modified Logistic and Gompertz models. Values of λ, A, and μ for β-carotene accumulation varied between 0.26 and 20.14 days, 57.48 to 198.76 pg β-carotene/cell, and 1.80 to 3.68 1/day, respectively. Results revealed that Logistic and Gompertz models could be used to describe the accumulation of β-carotene by D. salina as a function of salt concentrations, pH, and irradiance. The highest asymptotic value was predicted from Logistic and Gompertz models at pH 9.0, 48 kerg/(cm² s) light intensity, and 20% NaCl concentration.     

Metal cation binding by the hyperthermophilic microorganism,Archaea Methanocaldococcus Jannaschii,and its effects on silicification

Abstract: A series of experiments was conducted to determine the capacity of an archaeal strain, Methanocaldococcus jannaschii, to bind metals and to study the effects of metal binding on the subsequent silicification of the microorganisms. The results showed that M. jannaschii can rapidly bind several metal cations (Fe³⁺, Ca²⁺, Pb²⁺, Zn²⁺, Cu²⁺). Considering the lack of silicification of this strain without metal binding, these experiments demonstrate that Fe(III) ion binding to the cell wall components was of fundamental importance for successful silicification and, especially, for the excellent preservation of the cell wall. This study brings new elements to the understanding of fossilization processes, showing that the positive effect of Fe(III) on silicification, already known for Bacteria, can also apply to Archaea and that this preliminary binding can be decisive for the subsequent fossilization of these organisms. Knowledge of these mechanisms can be helpful for the search and the identification of microfossils in both terrestrial and extraterrestrials rocks, and in particular on Mars.     

Phylogeography and taxonomy of the Psorodonotus caucasicus (Orthoptera,Tettigoniidae) group: independent double invasion of the Balkans from the Caucasus

High mountain ranges within and around Anatolia have played an important role in the biogeography of mountainous organisms, which are threatened by climate change. Using the Psorodonotus caucasicus species group (PCG), whose range is the Caucasus, Anatolia and the Balkans, as a model group, this study aims to determine the importance of Anatolian mountain ranges and to estimate possible future effects of global warming on such lineages by establishing an analogy between interglacial dynamics and global warming. Twenty populations, representing all extant species of the PCG, were studied. Sequences of four mitochondrial loci and three nuclear loci were obtained and used in phylogenetic, time estimation and phylogeographic analyses of PCG members. Additionally, ecological modelling analyses were conducted to estimate the range of PCG members at present and during the last glacial maximum and the last interglacial, with the aim of determining the roles of altitudes and glacial cycles in shaping the distribution of the PCG. Phylogenetic analyses supported the monophyly of the PCG as a whole and each individual species with the exception of P. suphani. The radiation of the PCG started approximately 3 Ma, according to beast . Species distribution models suggested a wider range during the last glacial maximum than during the last interglacial and at present, but these models also suggested that present conditions represent a substantial range loss. The PCG dispersed to the Balkans through two independent corridors from the Caucasus. The following conclusions were reached based on the results: (i) the uplift of the Pontic and East Anatolian Blocks during the mid‐Pliocene and the closing of the Mediterranean and the Paratethys connection in the Plio–Pleistocene and the mid‐Pleistocene Transition are the main events that triggered the radiation of the PCG; (ii) the PCG radiated from a Caucasian origin and invaded the Balkans twice, first through Northern Anatolia and second via the ‘Taurus Way’ dispersal corridor; (iii) lowlands are a barrier to the dispersal of PCG members; (iv) the last four intense glacial periods had little effect on the radiation of the PCG; (v) the range of the PCG has receded substantially from its original southern margin, and P. salmani and P. anatolicus have become extinct since the 1950s, possibly because of global warming; and (vi) automatic species delimitation tests supported species status of the morphospecies P. caucasicus, P. macedonicus, P. fieberi, P. illyricus and P. ebneri, but not that of P. suphani, thus, P. suphani Taylan & Sirin, 2014 syn.n. synonymized with P. caucasicus (Fischer von Waldheim, 1846).     

Seed screening of three pine species for glyphosate sensitivity for forest restoration

Austrian black pine (Pinus nigra J.F. Arnold), Scots pine (Pinus sylvestris L.), and maritime pine (Pinus pinaster Aiton) are commonly used in restoration practices in the Mediterranean base including Turkey. Direct seeding can secure desired level of tree establishment and survival on degraded sites wherever, favorable safe sites are scattered throughout the landscape. Glyphosate is a commonly used herbicide for weed control in forest, nursery and restoration sites worldwide, due to its broad-spectrum efficacy and considerably less toxicity on the environment compared to other chemicals. The present study screened the glyphosate phytotoxicity of three dominant pine species in Turkey during a seed germination trial, after seeds had been presoaked in 15 different dose-glyphosate solutions varying between 0 and 5%, v:v. Glyphosate applications damaged seed germination speed more than cumulative germination rate. As a systemic herbicide, glyphosate appeared highly phytotoxic to Austrian black pine. Scots pine showed an intermediate glyphosate phytotoxicity. Maritime pine was the least sensitive species, tolerating glyphosate at ≤1% doses. In conclusion, glyphosate may be used at low doses on restoration sites seeded with maritime pine while it is not recommended to be used on degraded sites seeded with Austrian black pine and Scots pine.     

Biosorption of Basic Blue 7 by fungal cells immobilized on the green-type biomatrix of Phragmites australis spongy tissue

Biosorption is an effective alternative method for the control of water pollution caused by different pollutants such as synthetic dyes and metals. A new and efficient biomass system was developed from the passively immobilized fungal cells. The spongy tissue of Phragmites australis was considered as the carrier for the immobilization of Neurospora sitophila cells employed for the biosorption of Basic Blue 7. This plant tissue was used for the first time as a carrier for fungal cells. The biosorption was examined through batch- and continuous-mode operations. The biosorption process conformed well to the Langmuir model. Maximum monolayer biosorption capacity of the biosorbent was recorded as 154.756 mg g^?1. Kinetic findings showed a very good compliance with the pseudo-second-order model. The negative values of ΔG° indicated a spontaneous nature of the biosorption process and a positive value of ΔH° (14.69 kJ mol^?1) concluded favorable decolorization at high temperature. The scanning electron microscopy analysis showed that a porous, rippled, and rough surface of biomass system was covered with BB7 molecular cloud. IR results revealed that functional groups like –OH, –NH, and C?O participated to the decolorization. Breakthrough and exhausted points were found as 360 and 570 minutes, respectively. The biomass system was successfully applied to the treatment of real wastewater.     

Effects of gestational weight gain and body mass index on obstetric outcome

Abstract It is already known that maternal overweight, obesity, and morbid obesity are associated with adverse obstetric and neonatal outcomes. To assess the prevalence of overweight and obesity, and the impact of body mass index (BMI) on maternal and neonatal outcomes in Turkey. The study population consisted of 698 singleton pregnancies whose height and weight follow up were performed from the first trimester of pregnancy and whose deliveries were monitored in Trabzon, Turkey in July 2014–June 2015. The data obtained during the study were evaluated using SPSS 21 package program. The differences in variables were assessed by Chi-square-test for categorical data or by One-way Anova test for continuous data. The results were evaluated at a confidence interval of 95% and at a significance level of p?<?0.05. According to the BMI of the women in the study, 68.8% were in normal weight, 20.6% were overweight, 3.9% were obese, and the majority was in the 20–29 age group and 8–15.9?kg. The rate of cesarean, instrumental delivery, induction, episiotomy, late breastfeeding, low apgar (<7 at 5?min), neonatal intensive care unit admission requirement, the newborn at 4000?g or more in overweight (BMI 25–29.9) and obese (BMI?≥?30) pregnancies was higher and the first and second phases of labor were longer (p?<?0.05). The study showed that as the pre-pregnancy body mass index and gestational weight gain increased the rates of cesarean section and interventional delivery increased and the neonatal need for neonatal intensive care unit increased.     

Discovery of a new metal and NAD+-dependent formate dehydrogenase from Clostridium ljungdahlii

Over the next decades, with the growing concern of rising atmospheric carbon dioxide (CO₂) levels, the importance of investigating new approaches for its reduction becomes crucial. Reclamation of CO₂ for conversion into biofuels represents an alternative and attractive production method that has been studied in recent years, now with enzymatic methods gaining more attention. Formate dehydrogenases (FDHs) are NAD(P)H-dependent oxidoreductases that catalyze the conversion of formate into CO₂ and have been extensively used for cofactor recycling in chemoenzymatic processes. A new FDH from Clostridium ljungdahlii (ClFDH) has been recently shown to possess activity in the reverse reaction: the mineralization of CO₂ into formate. In this study, we show the successful homologous expression of ClFDH in Escherichia coli. Biochemical and kinetic characterization of the enzyme revealed that this homologue also demonstrates activity toward CO₂ reduction. Structural analysis of the enzyme through homology modeling is also presented.     

Investigation of the uterine structural changes in the experimental model with polycystic ovary syndrome and effects of vitamin D treatment: An ultrastructural and immunohistochemical study

In this study, we aimed to investigate the structural changes seen in the endometrium in experimental PCOS rat model and the effects of vitamin D treatment on these changes at immunohistochemical and electron microscopic levels. 24 prepubertal female rats were divided into three groups. Two groups were injected with dehydroepiandrosterone and one of them was treated with 1,25(OH)2 D3 at the same time. The control group was injected with sesame oil. At the end of the 28th day, the blood samples were collected. Uterus tissues were prepared for light and electron microscopic examinations. Epithelial, stromal and endometrial thickness measurements were investigated. Immunohistochemical staining was applied against caspase-3 and Ki-67. Serum AMH and estradiol levels were higher in PCOS group compared to the control group. Serum progesterone levels were similar in all groups. Endometrial, epithelial and stromal thickness measurements were increased in PCOS group compared to the control group, and decreased in the vitamin D treatment group compared to the PCOS group. Light and electron microscopic results of PCOS group showed an increase in apoptosis and proliferation. In the PCOS group, immunohistochemical staining of caspase-3 and Ki-67 were found to be higher than in the control group, but stainings were decreased with vitamin D treatment compared to PCOS group. Structural changes observed in endometrium may be related to implantation problems seen in patients with PCOS. Our studies suggest that vitamin D therapy may be beneficial in these patients.