The trace and major element composition of the leaves of some deciduous trees

Summary A number of factors concerned in the sampling of the leaves of deciduous trees for diagnostic purposes are considered.A method is described for sampling leaves prior to the spectrochemical determination of 21 trace and major constituents in order to study seasonal changes. The precision, generally around ± 10 per cent for samples of leaves or leaf blades, including analytical errors, is considered satisfactory for this type of investigation.Some comparisons of leaf blade and petiole contents are made and the effects of removal of surface contamination are considered. Marked differences between petiole and leaf blade contents must be taken into account in diagnostic applications of leaf analysis. For most elements surface contamination is shown to be insignificant even at a site adjoining a main road.     

Resolving fibrosis in the diseased liver: translating the scientific promise to the clinic

Liver fibrosis and its end-stage disease cirrhosis are a major cause of mortality and morbidity throughout the world. Fibrosis is a response to chronic liver injury or infection that if unabated leads to the replacement of normal functional liver tissue with scar tissue. Basic research over the past decade has generated a vastly improved knowledge of the cell and molecular biology of liver fibrosis that provides a framework on which to design and develop therapeutics. The field has also witnessed a genuine paradigm shift from the original dogma that liver fibrosis is only ever a progressive process, to the new understanding that liver fibrosis even in an advanced stage can be reversible. There is therefore renewed optimism that liver fibrosis may be cured providing that we develop therapies that halt the fibrogenic process and encourage the natural regenerative properties of the liver. The key to the design of effective therapeutics will be to exploit the ongoing discoveries pertaining to the biology and function of fibrogenic hepatic myofibroblasts and their interplay with other liver cells and with the hepatic extracellular matrix. This review provides a critique of those discoveries in basic research that provide the most promise for translation to the clinic. In addition, we review the latest developments in the search for minimal invasive diagnostic tests for fibrosis that will be essential for determining the efficacy of anti-fibrotic drugs.     

The Role of Sodium as a Surfactant and Suppressor of Non‐Radiative Recombination at Internal Surfaces in Cu2ZnSnS4

It is well‐known that sodium improves the performance of Cu₂ZnSnS₄ (CZTS) devices, yet the mechanism of the enhancement is still not fully understood. This work aims to present a unified account of the relationships between grain boundaries in CZTS, sodium content at these boundaries, non‐radiative recombination, and surfactant effects that produce large microstructural changes. Using temperature‐dependent photoluminescence measurements, it is demonstrated that samples containing dramatically different grain sizes display identical radiative and non‐radiative decay characteristics when sufficient sodium is present in the film. It is also shown that the sodium concentration needed to efficiently passivate non‐radiative defects is significantly less that the quantity needed to obtain micrometer‐sized CZTS grains. Finally, the high densities of donor‐acceptor pairs that are observed in CZTS films appear to reside within the grains themselves, rather than at grain boundaries.     

Sequential batch culture studies for the decolorisation of reactive dye by Coriolus versicolor

The white rot fungus Coriolus versicolor could decolorise reactive dye Remazol Brilliant Violet to almost 90%. The fungal mycelia removed color as well as COD up to 95% and 75%, respectively, in a batch reactor. Decolorising activity was observed during the repeated reuse of the fungus. It was possible to substantially increase the dye decolorising activity of the fungus by carefully selecting the operational conditions such as media composition, age of fungus and nitrogen source. The fungal pellets could be used for eight cycles during the long term operation, where medium and dye was replenished at the end of each cycle and the fungus was recycled. Presence of a nitrogen source and nutrient content of media played an important role in sustaining the decolorisation activity of the fungus. The form of nitrogen source (e.g. peptone vs. urea) was also important to maintain the decolorising activity with peptone showing better decolorisation.     

Regulation of Drosophila matrix metalloprotease Mmp2 is essential for wing imaginal disc:trachea association and air sac tubulogenesis

The Drosophila Dorsal Air Sac Primordium (ASP) is a tracheal tube that grows toward Branchless FGF-expressing cells in the wing imaginal disc. We show that the ASP arises from a tracheal branch that invades the basal lamina of the disc to juxtapose directly with disc cells. We examined the role of matrix metalloproteases (Mmps), and found that reducing Mmp2 activity perturbed disc-trachea association, altered peritracheal distributions of collagen IV and Perlecan, misregulated ASP growth, and abrogated development of the dorsal air sacs. Whereas the function of the membrane-tethered Mmp2 in the ASP is non-cell autonomous we find that it may have distinct tissue-specific roles in the ASP and disc. These findings demonstrate a critical role for Mmp2 in tubulogenesis post-induction, and implicate Mmp2 in regulating dynamic and essential changes to the extracellular matrix.     

Bovine Serum Albumin Binding and Drug Delivery Studies with PVA-Ferrofluid

This paper describes a single-step method for the biomimetic synthesis of stably suspended magnetite nanoparticles in poly(vinyl alcohol) termed ferrofluids. The challenge is to synthesize water based stable magnetic colloids with a control over the particle size and morphology for biomedical applications. The polymer possibly plays a dual role of a surfactant and a functionalizing agent. Transmission electron microscopy, infrared spectroscopy and vibrating sample magnetometry were used to investigate the properties of the synthesized ferrofluids. It has a strong affinity towards the tryptophan residues in bovine serum albumin protein as determined from the fluorescence emission studies. For in vivo applications this could indirectly mean a resistance to immune response and thus ensure long-term circulation. The ability of the synthesized ferrofluid to bind a che-motherapeutic drug ceftriaxone and its ionic release was observed. The polymer hydroxyl group allows drug-binding and the magnetic property allows targeting to specific sites. Magnetic hybrid fluids with combined advantages of magnetism and polymer open up new perspectives for applications.     

Leaching of Mercury from Carbonated and Non-Carbonated Cement-Solidified Dredged Sediments

This study investigated traditional cement-based and non-conventional (using accelerated carbonation) solidification/stabilization to treat 2 dredged sediments contaminated with mercury from two different locations in UK. Canal and estuarine-derived sediments were mixed with blended binders and powdered activated carbon. Fresh mixtures of sediment and cement were exposed to gaseous carbon dioxide and were allowed to carbonate for fixed time periods, after which they were cured for 28 days. Following curing, samples were leach tested to evaluate the fixation of mercury in the treated products. The results obtained indicated that both conventional and accelerated carbonated treatments were capable of reducing the concentration of mercury in the eluates to acceptable limits.     

An integrated diagnostic approach to understand drought tolerance in mulberry (Morus indica L.)

Four popular mulberry cultivars (Morus indica L. cvs.V-1, MR-2, S-36 and K-2) were assessed for drought tolerance with an integration of selective approaches. The potted plants were subjected to two watering treatments for 75 days: control pots were watered up to 100% field capacity (FC) and stressed pots were maintained at 25–30% FC. Net photosynthetic rate (P_n), stomatal conductance (g_s), transpiration rate (E) and instantaneous water use efficiency (WUE_i) were the key parameters to assess photosynthetic gas exchange performance. Drought caused marked down-regulation in leaf gas exchange in all cultivars (cvs) except V-1 which maintained better P_n, g_s, E and higher WUE_i under severe water deficit. All the four cvs also showed differential antioxidative responses under water stress. Higher concentrations of carotenoids, ascorbic acid, glutathione, α-tocopherol and proline were observed in the leaf extracts of V-1, while minimum accumulation of those metabolites was recorded with K-2 and S-36. An endogenous loss of α-tocopherol and higher lipid peroxidation were encountered in K-2, S-36 and MR-2, whereas V-1 showed minimum lipid peroxidation under water deficit regimes. Comparative morpho-anatomical analysis revealed a well-developed root system and a better anatomical architecture in V-1 which could further contribute tolerance during drought stress.     

Effect of cerebellar modulation on rat gastric secretion and enterochromaffin-like cell

Effect of cerebellar lesion and vestibular stimulation (VS) on the activity and alternation of ECL-cells along with changes in gastric volume and acid secretion was studied. The results suggest that cerebellar lesion caused increased gastric volume and acid secretion and tended to decrease ECL-cell density. On the other hand VS of nodular lesioned rats resulted in decrease of above parameter which became marked only after 21 days of nodular lesion.