Selection on flowering time in Mediterranean high-mountain plants under global warming

Under climate warming, plants will undergo novel selective pressures to adjust reproductive timing. Adjustment between reproductive phenology and environment is expected to be higher in arctic and alpine habitats because the growing season is considerably short. As early- and late-flowering species reproduce under very different environmental conditions, selective pressures on flowering phenology and potential effects of climate change are likely to differ between them. However, there is no agreement on the magnitude of the benefits and costs of early- vs. late-flowering species under a global warming scenario. In spite of its relevance, phenotypic selection on flowering phenology has rarely been explored in alpine plants and never in Mediterranean high mountain species, where selective pressures are very different due to the summer drought imposed over the short growth season. We hypothesized that late-flowering plants in Mediterranean mountains should present stronger selective pressures towards early onset of reproduction than early-flowering species, because less water is available in the soil as growing season progresses. We performed selection analyses on flowering onset and duration in two high mountain species of contrasting phenology. Since phenotypic selection can be highly context-dependent, we studied several populations of each species for 2 years, covering their local altitudinal ranges and their different microhabitats. Surrogates of biotic selective agents, like fruitset for pollinators and flower and fruit loss for flower and seed predators, were included in the analysis. Differences between the early- and the late-flowering species were less than expected. A consistent negative correlational selection of flowering onset and duration was found affecting plant fitness, i.e., plants that bloomed earlier flowered for longer periods improving plant fitness. Nevertheless, the late-flowering species may experience higher risks under climate warming because in extremely warm and dry years the earlier season does not bring about a longer flowering duration due to summer drought.     

Sustained Release of Poorly Water-Soluble Drug from Hydrophilic Polymeric Film Sandwiched Between Hydrophobic Layers

This proof-of-concept study explores the feasibility of using a drug-loaded hydrophilic polymeric layer sandwiched between two hydrophobic layers for improving film drug load while achieving sustained release of poorly water-soluble drug. Such films having total thickness in range ~?146–250 μm were prepared by slurry-based casting using hydrophilic hydroxypropyl methylcellulose (HPMC) as matrix layer containing fenofibrate (FNB) as the model drug, encased between two very thin rate-limiting layers of 10 μm each of hydrophobic poly-?-caprolactone (PCL). Film precursor slurry consisted of HPMC with plasticizer and water along with micronized FNB powders, which were dry-coated with hydrophilic silica. Characterization techniques demonstrated the presence of homogeneously dispersed crystalline FNB in films. The films are very thin and hence two-dimensional; hence, average drug load per unit area in range ~?5 to ~?9 mg/cm² could be achieved by altering the thickness of the drug matrix layer. Drug amount and drug content uniformity were measured through assay of ten circular samples ~?0.712 cm² in area punched out using a circular-shaped punch tool. Drug release rate was investigated using USP IV flow-through cell and surface dissolution imaging system. Thinner films followed Fickian diffusion, and thicker films followed non-Fickian anomalous diffusion. Overall, the application of middle layer thickness could be used as a tool to manipulate drug load without the need for altering its formulation or precursor preparation by changing its thickness, hence achieving relatively high drug loading yet having sustained release of drug.     

Recombinant Galectins of <Emphasis Type="Italic">Haemonchus contortus</Emphasis> Parasite Induces Apoptosis in the Peripheral Blood Lymphocytes of Goat

The effect of Haemonchus contortus galectin peptides rHco-gal-m/f to induce apoptosis in the peripheral blood lymphocytes (PBLCs) of goats was investigated. Analysis of apoptosis was carried out with agarose gel electrophoresis, flow cytometry and transmission electron microscopy. The results indicated that there were visible apoptosis bodies and typical DNA ladders by genomic DNA fragmentation. The quantitative analysis of apoptosis by flow cytometry indicated that rHco-gal-m/f peptides induced apoptosis was time and dose dependent. Ultrastructural studies of the PBLCs revealed that a large number of apoptotic cells were present in galectin-treated cells, which had the typical morphologic changes of apoptosis such as reduction of the cytoplasmic volume, loss of cell surface microvilli, chromatin condensation and fragmentation of the apoptotic cells into small apoptotic bodies.     

Hidden Markov model speed heuristic and iterative HMM search procedure

Background  

Profile hidden Markov models (profile-HMMs) are sensitive tools for remote protein homology detection, but the main scoring algorithms, Viterbi or Forward, require considerable time to search large sequence databases.     

Evaluation of antioxidant activity of <Emphasis Type="Italic">Melothria maderaspatana in vitro</Emphasis>

In this study, an aqueous extract of leaves from Melothria maderaspatana was tested for in vitro antioxidant activity. Free radical scavenging assays, such as hydroxyl radical, hydrogen peroxide, superoxide anion radical and 2,2-diphenyl-1-picryl hydrazyl (DPPH), 2,2’-azinobis-(3-ethyl-enzothiazoline-6-sulfonic acid) (ABTS) radical scavenging, and reducing power assay, were studied. The extract effectively scavenged hydroxyl radical, hydrogen peroxide and superoxide anion radicals. It also scavenged DPPH and ABTS radicals. Furthermore, it was found to have reducing power. All concentrations of leaf extract exhibited free radical scavenging and antioxidant power, and the preventive effects were in a dose-dependent manner. The antioxidant activities of the above were compared to standard antioxidants such as butylated hydroxytoluene (BHT), ascorbic acid, and α-tocopherol. The results obtained in the present study indicate that the M. maderaspatana extract could be considered a potential source of natural antioxidant.     

ALDH2 polymorphism for the risk of cervical carcinogenesis

To investigate the clinical significance of ALDH2 genetic polymorphisms in cervical carcinogenesis. ALDH2 polymorphisms together with human papillomavirus (HPV) types were examined in a total of 195 cervical smear in exfoliated cervical cell samples using Real-Time polymerase chain reaction (PCR) System. The frequency for the AG+AA genotype was seven in the normal group (70.0 %), 16 in the LSIL group (57.1 %), and 27 in the HSIL group (90.0 %). A significant difference was found between the LSIL and HSIL groups (P = 0.0064). Patients with HSIL lesions frequently had high-risk HPV infections and concurrently belonged to the AG+AA group. ALDH2 genotype in cervical cell samples may be associated with more severe precancerous lesions of the cervix in a Japanese population.     

Mapping ephemeral wetlands: manual digitisation and logistic regression modelling in Nelson Mandela Bay Municipality,South Africa

Until recently, little research has been conducted on the distribution and structure of ephemeral systems in semi-arid areas. This information is critical for appropriate wetland management and conservation. The Nelson Mandela Bay Municipality is a semi-arid area along the south-eastern coastline of the Eastern Cape Province of South Africa. The Municipality encapsulates a wide range of geological and geomorphological features as well as vegetation types within an area of some 1950 km², providing an ideal area for such research. The distribution and abundance of wetlands were defined, and a logistic regression (LR) model was used to establish whether this modelling technique is viable in semi-arid areas with highly variable rainfall patterns. Wetlands were delineated manually using geographical information systems, high-resolution aerial photographs and environmental data. More than 1700 wetland polygons were identified, with 80% of the systems being categorised as depressions, seeps and wetland flats. Unchannelled (8%) and channelled (7%) valley bottom wetlands and floodplain wetlands (5%) were also identified. The wetland database was then used to create a wetland occurrence probability model. There were 19 environmental variables used to develop the LR model, with eight variables used in the final model output. The predictive capacity of the model was good, with an area under curve value of 0.68 and an overall accuracy of 66%. This indicates that probabilistic wetland models are useful in highly variable environments with high numbers of small (<1 ha) wetlands. Such predictive models provide a tool to assist in improving the accuracy of land cover datasets in semi-arid areas, and can be used to inform management decisions on flood risk areas and key conservation zones. In addition, abiotic variables that are significant in the model output provide an indication of the factors influencing wetland functioning in the region.     

Secondary succession of plant communities in a subtropical mountainous region of SW China

Since 1985, originally forested mountainous areas of China have been allowed to return to their natural state after years of exploitation including agriculture, development, and logging. The reforms began earlier in less accessible locations, so that today the successional process is more advanced there. The vegetation in Luquan, Qiongzhusi, and Xishan near Kunming, central Yunnan, exhibits, in a limited area, a range of stages of plant succession that are widely encountered throughout the broader region, and thus affords a special opportunity for a comprehensive study. We analyzed the successional sequence of these various plant communities. They ranged from pioneer coniferous and/or pioneer deciduous broad-leaved stands to pre-mature semi-humid evergreen broad-leaved stands, through mixed coniferous and broad-leaved or mixed deciduous and evergreen broad-leaved stands. The succession proceeded from pioneer coniferous Pinus and Keteleeria, and deciduous Platycarya and Alnus, to late-successional evergreen broad-leaved Cyclobalanopsis and Castanopsis. Two regeneration types of woody species in either the early successional (15–50 years), the mid-successional (40–80 years), or the late-successional (80–180 years) stage were classified. Relatively high species diversity was found in the seral phase at the three study sites. The late-successional stage was commonest where human disturbance was least evident. Poor soil chemical properties under pioneer Pinus were seen as a limitation to plant growth, while the abundance of Alnus at the early stage led to an improved level of organic matter and nitrogen.     

Improving the accuracy of a solid spherical source radius and depth estimation using the diffusion equation in fluorescence reflectance mode

Background  

Non-invasive planar fluorescence reflectance imaging (FRI) is used for accessing physiological and molecular processes in biological tissue. This method is efficiently used to detect superficial fluorescent inclusions. FRI is based on recording the spatial radiance distribution (SRD) at the surface of a sample. SRD provides information for measuring structural parameters of a fluorescent source (such as radius and depth). The aim of this article is to estimate the depth and radius of the source distribution from SRD, measured at the sample surface. For this reason, a theoretical expression for the SRD at the surface of a turbid sample arising from a spherical light source embedded in the sample, was derived using a steady-state solution of the diffusion equation with an appropriate boundary condition.