Litter Fall Dynamics of Restored Mangroves (Rhizophora mucronata Lamk. and Sonneratia alba Sm.) in Kenya

Mangrove forests are active carbon sinks and important for nutrient cycling in coastal ecosystems. Restoration of degraded mangrove habitats enhances return of ecosystem goods and services, including carbon sequestration. Our objective was to assess the restoration of primary productivity of reforested mangrove stands in comparison with natural reference stands in Gazi Bay, Kenya. Litter fall data were collected in nine Rhizophora mucronata and Sonneratia alba monospecific stands by use of litter traps over 2 years. Litter was emptied monthly, dried, sorted, and weighed. The reforested and natural stands showed seasonality patterns only in the production of reproductive material. Leaves constituted the highest percentage to total litter fall. Litter productivity rates for the R. mucronata stands were not significantly different and ranged from 6.61–10.15 to 8.36–11.02 t ha^?1 yr^?1 for the restored and natural stands, respectively. The productivity of 5 years R. mucronata stands reached 5.22 t ha^?1 yr^?1 and was significantly different from other stands. Litter productivity rates for S. alba stands was 7.77–7.85 for the restored stands and 10.15 t ha^?1 yr^?1 for the natural stand but differences were not significant. Our results indicate that plantations of at least 11 years have attained litter productivity rates comparable to the natural forests. This suggests that productivity of replanted mangroves is likely to reach complete recovery by this age under the prevailing environmental conditions.     

Characterization of Soil Contamination in Miduk Mining District,SW Iran

In this study, 30 soil samples were collected from 0–5 cm and 15–20 cm depths in the vicinity of the Miduk Porphyry Copper Mine in Kerman Province, southeast Iran. The samples were analyzed for total concentrations of eight potentially toxic elements. The bioavailability of trace elements is determined using sequential extraction analysis. Average concentrations of As, Cd, Cr, Cu, Mo, Ni, Pb, and Zn in soil samples are 26.9, 0.49, 56.31, 201.18, 1.77, 45.6, 83.87, and 191.94 mg kg^?1, respectively. Also, to assess the bioaccumulation of the analyzed elements, the roots and the leaves of three plant species were sampled and analyzed. The mobility of the analyzed trace elements shows the following decreasing order: Cd > Mo > Ni > Zn > Cu > Cr >Pb> As. The distribution pattern of elements indicates that elemental concentration in Miduk soils is highly influenced by bedrock composition, while soil pollution is mostly affected by ancient mining.     

Clinical Breast Examination As the Recommended Breast Cancer Screening Modality in a Rural Community in Malaysia; What Are the Factors That Could Enhance Its Uptake?

Breast cancer is the most common cause of deaths and the most frequently diagnosed cancer among women worldwide. This study aimed to determine the prevalence of breast cancer screening, specifically on clinical breast examination, and the predictors of its uptake among women in Malaysia. A cross-sectional study was carried out in five selected districts whereby women aged between 20 to 64 years old, from a total of 1000 households were interviewed. A total of 1192 women responded to the survey of which 53.3% reported had ever done clinical breast examination. Significant associations with clinical breast examination were noted for income and distance from the hospital. These factors should be considered in developing interventions aimed at promoting clinical breast examination. In particular, healthcare providers should be proactive in raising awareness about clinical breast examination among women in Malaysia.     

Protein degradation with photoactivated enediyne-amino acid conjugates

A series of photoactivated enediynes was prepared, and successfully employed for the selective degradation of target proteins.     

Decisional tool to assess current and future process robustness in an antibody purification facility

Increases in cell culture titers in existing facilities have prompted efforts to identify strategies that alleviate purification bottlenecks while controlling costs. This article describes the application of a database‐driven dynamic simulation tool to identify optimal purification sizing strategies and visualize their robustness to future titer increases. The tool harnessed the benefits of MySQL to capture the process, business, and risk features of multiple purification options and better manage the large datasets required for uncertainty analysis and optimization. The database was linked to a discrete‐event simulation engine so as to model the dynamic features of biopharmaceutical manufacture and impact of resource constraints. For a given titer, the tool performed brute force optimization so as to identify optimal purification sizing strategies that minimized the batch material cost while maintaining the schedule. The tool was applied to industrial case studies based on a platform monoclonal antibody purification process in a multisuite clinical scale manufacturing facility. The case studies assessed the robustness of optimal strategies to batch‐to‐batch titer variability and extended this to assess the long‐term fit of the platform process as titers increase from 1 to 10 g/L, given a range of equipment sizes available to enable scale intensification efforts. Novel visualization plots consisting of multiple Pareto frontiers with tie‐lines connecting the position of optimal configurations over a given titer range were constructed. These enabled rapid identification of robust purification configurations given titer fluctuations and the facility limit that the purification suites could handle in terms of the maximum titer and hence harvest load. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 28: 1019–1028, 2012     

Subsampling Herbarium Collections to Assess Geographic Diversity Gradients: A Case Study with Endemic Orchidaceae and Rubiaceae in Cameroon

We compiled herbarium specimen data to provide an improved characterization of geographic patterns of diversity using indices of species diversity and floristic similarity based on rarefaction principles. A dataset of 3650 georeferenced plant specimens belonging to Orchidaceae and Rubiaceae endemic to Atlantic Central Africa was assembled to assess species composition per half‐degree or one‐degree grid cells. Local diversity was measured by the expected number of species (S_k) per grid cell found in subsamples of increasing size and compared with raw species richness (S_R). A nearly unbiased estimator of the effective number of species per grid cell was also used, allowing quantification of ratios of ‘true diversity’ between grid cells. Species turnover was measured using a presence/absence‐based similarity index (Sørensen) and an abundance‐based index that corrects for sampling bias (NNESS). Our results confirm that the coastal region of Cameroon is more diverse in endemic species than those more inland. The southern part of this coastal forest is, however, as diverse as the more intensively inventoried northern part, and should also be recognized as an important center of endemism. A strong congruence between Sørensen and NNESS similarity matrices lead to similar delimitations of floristic units. Hence, heterogeneous sampling seems to confer more bias when measuring patterns of local diversity using raw species richness than species turnover using Sørensen index. Overall, we argue that subsampling methods represent a useful way to assess diversity gradients using herbarium specimens while correcting for heterogeneous sampling effort. Abstract in French is available in the online version of this article.     

True volumetric method for flow cytometric enumeration of CD34 + stem cells and its agreement with a standard bead-based single-platform protocol

Background aimsStem cells are commonly enumerated with bead-based methods in blood and marrow progenitor cell transplantation centers. We compared the International Society of Hematotherapy and Graft Engineering (ISHAGE) bead-based method with a true volumetric one that obviates the use of fluorescent beads for enumeration.MethodsFrom 31 samples, including 15 peripheral blood samples and 16 leukapheresis products, CD34 ⁺ cells were enumerated with the single-platform bead-based ISHAGE method and a true volumetric method. After exclusion of two outliers, one from the peripheral blood group and the other from the leukapheresis group, the results were compared.ResultsIn the peripheral blood category, no significant difference was observed. However, a proportional systematic error was seen in the leukapheresis group. The systematic error was corrected in the leukapheresis group using a regression line equation. The 95% confidence interval of differences was [–5.83, 2.18] for the peripheral blood and [–38.40, 38.77] for the leukapheresis group after correction of the systematic error.ConclusionsThe true volumetric method is a simple and reliable approach that can be used instead of the more popular bead-based procedures.     

Rapid bioassays to evaluate the plant growth promoting activity of <Emphasis Type="Italic">Ascophyllum nodosum</Emphasis> (L.) Le Jol. using a model plant, <Emphasis Type="Italic">Arabidopsis thaliana</Emphasis> (L.) Heynh

Ascophyllum nodosum extract products are used commercially in the form of liquid concentrate and soluble powder. These formulations are manufactured from seaweeds that are harvested from natural habitats with inherent environmental variability. The seaweeds by themselves are at different stages of their development life-cycle. Owing to these differences, there could be variability in chemical composition that could in turn affect product consistency and performance. Here, we have tested the applicability of using Arabidopsis thaliana as a model to study the activity of two different extracts from A. nodosum. Three different bioassays: Arabidopsis root-tip elongation bioassay, Arabidopsis liquid growth bioassay and greenhouse growth bioassay were evaluated as growth assays. Our results indicate that both extracts promoted root and shoot growth in comparison to controls. Further, using Arabidopsis plants with a DR5:GUS reporter gene construct, we provide evidence that components of the commercial A. nodosum extracts modulates the concentration and localisation of auxins which could account, at least in part, for the enhanced plant growth. The results suggest that A. thaliana could be used effectively as a rapid means to test the bioactivity of seaweed extracts and fractions.     

Self-built Supercritical CO2 Anti-solvent Unit Design, Construction and Operation using Carbamazepine

The purpose of this study was to design and build a supercritical CO₂ anti-solvent (SAS) unit and use it to produce microparticles of the class II drug carbamazepine. The operation conditions of the constructed unit affected the carbamazepine yield. Optimal conditions were: organic solution flow rate of 0.15 mL/min, CO₂ flow rate of 7.5 mL/min, pressure of 4,200 psi, over 3,000 s and at 33°C. The drug solid-state characteristics, morphology and size distribution were examined before and after processing using X-ray powder diffraction and differential scanning calorimetry, scanning electron microscopy and laser diffraction particle size analysis, respectively. The in vitro dissolution of the treated particles was investigated and compared to that of untreated particles. Results revealed a change in the crystalline structure of carbamazepine with different polymorphs co-existing under various operation conditions. Scanning electron micrographs showed a change in the crystalline habit from the prismatic into bundled whiskers, fibers and filaments. The volume weighted diameter was reduced from 209 to 29 μm. Furthermore, the SAS CO₂ process yielded particles with significantly improved in vitro dissolution. Further research is needed to optimize the operation conditions of the self-built unit to maximize the production yield and produce a uniform polymorphic form of carbamazepine.