Developing Frameworks to Assess Impacts of Multiple Drivers of Change on Grassland System

Grassland systems face many simultaneous pressures including market and policy compliance that operate from local to global scale. The ability to adapt to these pressures against a background of constrained natural resources and inputs is vital to the continued success of the grassland livestock industry and all those dependent on its outputs. New Zealand and Uruguay collaborators have been developing a suite of tools and processes embedded in an “innovation platform” to enable farmers, agribusiness and policy planners to engage and collectively learn about the impact of their interacting individual decisions and strategies. We describe the generic framework and demonstrate examples of the tools and processes used and their applicability across scale in both New Zealand and Uruguay

Effect of α-Hgl_2 epitaxial growth on the defect structure of CdTe:Ge substrates

The aα-HgI_2/CdTe:Ce heterostructures have been studied by cathodoluminescence (CL) in the scanning electron microscope. The alpha-HgI2 expitaxial growth was shown to cause an enhancement of the CL intensity in a layer of the substrate extending up to about 500 mu m from the α-Hgl_2 /CdTe:Ge interface. CL spectra of the layer reveal the appearance of a band related to tellurium vacancies as well as the decrease of the emission attributed to defect complexes involving Ge. The data obtained indicate that Ge-impurity gettering and V-Te generation at the interface take place during α-Hgl_2 epitaxial growth

High-performance visible light photodetectors based on inorganic CZT and InCZT single crystals

Herein, the optoelectrical investigation of cadmium zinc telluride (CZT) and indium (In) doped CZT (InCZT) single crystals-based photodetectors have been demonstrated. The grown crystals were configured into photodetector devices and recorded the current-voltage (I-V) and current-time (I-t) characteristics under different illumination intensities. It has been observed that the photocurrent generation mechanism in both photodetector devices is dominantly driven by a photogating effect. The CZT photodetector exhibits stable and reversible device performances to 632 nm light, including a promotable responsivity of 0.38 AW−1, a high photoswitch ratio of 152, specific detectivity of 6.30 × 1011 Jones, and fast switching time (rise time of 210 ms and decay time of 150 ms). When doped with In, the responsivity of device increases to 0.50 AW−1, photoswitch ratio decrease to 10, specific detectivity decrease to 1.80 × 1011 Jones, rise time decrease to 140 ms and decay time increase to 200 ms. Moreover, these devices show a very high external quantum efficiency of 200% for CZT and 250% for InCZT. These results demonstrate that the CZT based crystals have great potential for visible light photodetector applicationsAuthors from KKU express their appreciation to the Deanship of Scientifc Research at King Khalid University for funding this work through research groups program under grant number R.G.P. 2/42/4

Application of cathodoluminescence microscopy to the study of native acceptors in gallium antimonide

Cathodoluminescence in the scanning electron microscope is used to ivestigate growth and prosess induced defects in GaSb crystals. In particular, luminescence emission has been used to study the nature of acceptor defects present after different annealing and irradiation treatments

Anticancer Activity of Alkynylgold(I) with P(NMe2)3 Phosphane in Mouse Colon Tumors and Human Colon Carcinoma Caco-2 Cell Line

New alkynylgold(I) with P(NMe2)3 (HMPT) phosphane complexes, [Au(CC-R)(HMPT)] (R= 4-Ph, 4-MePh, 4-OMe, 4-Br, 4-Cl, 2-py, and 3-py) have been synthesized and characterized, including X-ray studies of complexes with R= 4-OMe and 4-Br; additionally, their physicochemical properties and anticancer activity have been tested. Due to the great water solubility of the HMPT phosphane, all the complexes exhibit an optimal balance of hydrophilicity/lipophilicity. Also, all of these complexes are quite stable in physiological conditions and interact well enough with the transport protein BSA. All complexes exhibit a higher anticancer activity against Caco-2 cells than cisplatin, and some of them do not present cytotoxic activity against enterocyte-like differentiated cells. The selective complexes are proapoptotic drugs by the exposure of phosphatidylserine, results that are also confirmed in primary cultures from mouse colon tumors. Complexes with a halogen unit also arrest the cell cycle in G2/M phase. It is thought that maybe these apoptosis processes are promoted by the observed oxidative damage in the membrane lipids, as a consequence of the inhibition of the thioredoxin reductase enzyme. Based on our results, we conclude that five of our complexes are good candidates to be used in chemotherapy

Effect of implantoplasty on the elastic limit of dental implants of different diameters

Background Implantoplasty reduces both implant diameter and the thickness of its walls, subsequently reducing the ability of the implant to resist fracture in response to functional load. In combination with an increase in the crown-implant ratio due to bone loss, this could increase the lever effect, which in presence of high masticatory forces or parafunctional habits, could lead to complications such as fracture of the implant or loosening of the prosthetic screw. Objectives To determine the elastic limits of internal connection, dental implants of different designs and diameters after an implantoplasty. Materials and methods This in vitro study included 315 tapered internal connection titanium dental implants, the threads of which were removed with an industrial milling machine-for standardized implantoplasty (IMP1; n = 105)-or with the conventional approach-manually, using high-speed burs (IMP2; n = 105). The remaining 105 implants were used as controls. The final implant diameters were recorded. The quality of the newly polished surfaces was assessed by scanning electron microscopy. All implants were subjected to a mechanical pressure resistance test. A Tukey''s test for multiple comparisons was used to detect differences in the elastic limit and final implant diameters between the implant groups. Results There were statistically significant differences in the elastic limit between the IMP1, IMP2, and control groups (p < 0.05). Furthermore, the implant diameter was significantly smaller in the IMP1 and IMP2 groups (p < 0.05). Scanning electron microscopy revealed smooth implant surfaces in the IMP1 and IMP2 groups, with some titanium particles visible in the IMP1 group. Conclusions Implantoplasty significantly decreased the elastic limit of internal connection titanium dental implants, especially in those with a smaller diameter (3-3.5 mm)

Cathodoluminescence characterization of InGaSb crystals

The nature and the spatial distribution of radiative defects in In(X)Ga(1-x)Sb grown by the vertical Bridgman method have been studied by cathodoluminescence (CL) in a scanning electron microscope. The CL results have been complemented by X-ray microanalysis and backscattered electron imaging to relate the local luminescence properties to the chemical composition. Measurements of the band gap energy from the CL spectra, supported by X-ray compositional mappings, reveal an effective incorporation of In in the matrix, leading to the fori-nation of the ternary alloy in the whole volume of the ingot. A band often observed in the CL spectra, peaked at about 20 meV below the band gap energy, is attributed to the presence in the ternary alloy of an acceptor level that would correspond to the V(Ga)-Ga(Sb) acceptor in GaSb