Overcoming Major Environmental and Production Challenges in Cattle Owned by Smallholder Farmers in the Tropics

The world’s population is expected to increase significantly by 2050, leading to significantly increased demands for meat and dairy products. However, cattle are major emitters of greenhouse gases that speed up climate change. To achieve food security by 2050, livestock enterprises need to double their outputs from constant resources, in the face of increased competition for inputs such as land, water, grain and labour. To cope with climate change, the livestock need to be productive under hotter and drier climates and be able to tolerate increased challenges from parasites and vector-borne diseases. The best way for smallholder cattle farmers in tropical low-medium income countries to overcome these multiple challenges is to focus on improving the productivity of their herds. This paper discusses a range of simple and cost-effective options already available to smallholder farmers to significantly improve the productivity and profitability of their herds and by doing so, they will indirectly reduce greenhouse gas emissions from their cattle and improve the natural resource base on which their cattle graze. Improved herd productivity will in turn deliver significant social, environmental, economic and livelihood benefits to the smallholder farmers themselves and the communities and value chains in which they operate

The Membrane as a barrier or target in cancer chemotherapy

The overall aim of the project was to investigate the role of the cell membrane as a barrier and/or target for drug action and relate this to the development of strategies for overcoming multiple drug resistance (MDR). The effects of doxorubicin on various bacterial strains expressing different levels of anionic phospholipid were compared. Giowth of wild-type Echerichia coli (E. coli) strain MRE600 was severely affected up to 9 hours following doxorubicin treatment (15uM), but resistance occurred after 9 hours. E. coli strain FIDL1 1 was resistant to doxorubicin (1 O0piM) over 9 hours, however, increasing the anionic lipid content showed little difference in sensitivity. The mouse mammary tumour cell line (EMT6-S) and MDR sub-line (EMT6-R) were characterised with regard to growth kinetics, susceptibility to doxorubicin and membrane lipid composition. The log phase doubling times (h) were found to be 21.8 (EMT6-S)and 25.0 (EMT6-R) and the IC 50 values for doxorubicin to be 2.2 x 10-8 M and 1.8 x 10-6 M for EMT6-S and EMT6-R cells, respectively. No difference was observed between the phospholipid profiles of the two cell lines and total fatty acid composition was similar, however, the level of linoleic acid appeared to be higher in the resistant cells. The photocytotoxicity of the cationic dyes methylene blue (MB), toluidine blue (TBO) and Victoria blue BO (VBBO) against the EMT6 cell lines was compared to the cyotoxic effect of doxorubicin and cis-platinurn. The cytotoxic effect of VBBO was enhanced 10-fold by illumination (7.2 J cm2) in both EMT6-S and EMT6-R cells. In order to overcome resistance, however, the EMT6-R cells required a 10-fold greater level of the dye than the parental cells to reach an IC50 value. By contrast, doxorubicin required almost a 100-fold increase in concentration to overcome this resistance. Pre-treatment of EMT6-S and EMT6-R cells with low concentrations of VBBO resulted in a 2-fold increase in doxorubicin toxicity in both cell lines. Pre-treatment with MB and TBO resulted in a 1.4-fold and 2-fold increase in doxorubicin toxicity, respectively, in the sensitive cells, increasing to 2-fold and 3-fold, respectively in the resistant cells. Glutathione (GSH) depletion of EMT6-S and EMT6-R cells did not enhance the photocytotoxicity of VBBO, suggesting that the primary site of action of VBBO is at an intracellular site not protected by GSH or that the mechanism of action is not via the in situ generation of singlet oxygen. Addition of the chemosensitizer, verapamil (7gM), increased the efficacy of doxorubicin by 2-fold in EMT6-S cells and by 18-fold in EMT6-R cells. By contrast, the presence of verapamil did not increase the cytotoxicity of YBBO in either cell line. A series of compounds, PVB, MVB and MOVB, based on the skeleton of VBBO was examined. VBBO was found to be the most effective photosensitizer. The rate of uptake for VBBO, MVB and PVB appeared to be very similar, whereas that of MOVB was slower. The uptake/dose trend was also similar four all four drugs tested and conelated to the levels of lipophilicity of the agents. Confocal microscopy studies showed all the photosensitizers to be distributed widely throughout the cytoplasm, with considerable accumulation of VBBO and PVB in the perinuclear region. Time course studies showed the intracellular distribution of VBBO in both cell lines to be similar, although uptake of the drug appeared slower in the resistant cell line. VBBO was clearly localised throughout the cytoplasm, in a punctate pattern, which may be consistent with the widespread distribution of mitochondria. No interaction with the plasma membrane was evident. By contrast, doxorubicin was found to localise mainly in the nucleus of the sensitive cell line, whereas no nuclear involvement was seen in the resistant cells. The drug was also effluxed more rapidly from EMT6-R cells than EMT6-S cells. Time course studies with EMT6-S cells showed that the drug clearly interacts with both the plasma membrane and the nucleus. These results indicate that the main modes of action for the two drugs differ markedly, suggesting interaction with both the membrane and the nucleus in the case of doxorubicin, but possibly mitochondrial involvement for VBBO

Dynamic performance of squeeze-film bearings

Earlier work has shown that oil-film forces can be modelled by linear coefficients. Identification techniques were used to generate numerical values for these coefficients. This paper has shown the invalidity of applying the perturbation techniques normally used in bearing studies to derive expressions for linearized coefficients to represent a cavitated oil-film. An alternative approach was developed based upon energy techniques to obtain estimates for linearized coefficients. Some current work being undertaken suggests that an alternative analytical approach is possible. These results will be reported in due course

Meth­yl(phen­yl)phosphinic acid

The crystal structure of the title compound, C7H9O2P, displays O—H⋯O hydrogen bonding , which links individual mol­ecules related via the c-glide plane and translational symmetry along the crystallographic b-axis direction into continuous chains

Automatic Road Survey by Using Vehicle Mounted Laser for Road Asset Management

In most countries local roads (i.e., urban and rural) form over 80% of the entire road network and constitute the country's largest asset value. In order for local roads to remain fit for purpose and maintain their value, they require periodic maintenance. To make the best use of scarce maintenance resources, road maintenance needs to be preventative which requires the condition of the road to be assessed periodically. Traditional road surveys suffer from the lack of repeatability and reproducibility, are high cost and time consuming. This work proposes a vehicle mounted point laser system for the automated, rapid and inexpensive measurement of a major mode of local road deterioration, namely fretting. Compared to other technologies such as Ground Penetrating Radar (GPR), visual sensors and the Mobile Laser Scanning (MLS) system, the point laser requires less computational power, is less sensitive to the surrounding environment and is of comparatively low cost. A robust approach is proposed which consists of a number of pre-processing algorithms to deal with noise and the effects of the vehicles dynamic motion, and a signal processing algorithm which analyses histograms of the distance from the road surface measured by the laser to account for changes in road texture. Road fretting measured by the proposed system on a variety of roads is compared with fretting determined using a standard visual assessment process. The results indicate that the proposed system can measure road fretting to the levels of detail which are suitable for planning, programming and preparations road management functions

An experimental and theoretical study of transient negative ions in Mg, Zn, Cd and Hg

A range of experimental and theoretical techniques have been applied to the study of transient negative ions (resonances) formed in electron scattering from the Group II metals Mg, Zn, Cd, and Hg at incident electron energies below the first ionization potential. A wealth of resonance structures have been observed and from the experimental observations and theoretical information, classifications are proposed for some of these negative ion states

Effect of Silver Diamine Fluoride and Potassium Iodide Treatment on Secondary Caries Prevention and Tooth Discolouration in Cervical Glass Ionomer Cement Restoration

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Project Report No. 60, Observed Per-Acre Volume Growth Trends, 28 Individual Observations, Unthinned Loblolly Pine Plantations East Texas

Individual plot data from the East Texas Pine Plantation Research Project were available for analysis in this study. Each plot consists of two subplots. Each subplot is considered an observation. The analysis was limited to individual observations ages 24 years and older. All observations are unthinned. For each observation, cubic feet total stem wood and bark per acre was calculated. Based on these values, MAI (mean annual increment) was calculated. The values (plus observed trees per acre) are depicted in graphs on the next 28 pages

Project Report No. 61, Observed Per-Acre Basal Area Growth Trends, 28 Individual Observations, Unthinned Loblolly Pine Plantations

Individual plot data from the East Texas Pine Plantation Research Project were available for analysis in this study. Each plot consists of two subplots. Each subplot is considered an observation. The analysis was limited to individual observations ages 24 years and older. All observations are unthinned