A second polymorph of chlorido(hydroxy­diphenyl­phosphane)gold(I)

The title complex, [AuCl{(C6H5)2P(OH)-κP}] or [AuCl(C12H11OP)], contains two independent mol­ecules in the asymmetric unit and is a polymorph of a previously reported structure [Hollatz et al. (1999 ▶) J. Chem. Soc. Dalton Trans. pp. 111–114]. The crystal structure exhibits inter­molecular Au⋯Au inter­actions with alternate distances of 3.0112 (3) Å and 3.0375 (2) Å. The Cl—Au—P bond angle varies between different mol­ecular units, depending on the degree of influence of the intra­molecular the O—H⋯Cl hydrogen bond; the angle thus varies between negligible distortion from linearity at 179.23 (3)° and more significant distortion at 170.39 (4)°, which differs from the previously reported polymorph in which both these angles are approximately 170°. The Au—Cl [2.3366 (9) and 2.3131 (10)Å] and Au—P [2.2304 (10) and 2.2254 (10) Å] bond lengths vary slightly between the two independent mol­ecules but overall, the bond lengths are in good agreement with those in the previously reported polymorph

Vine Signal Extraction - an Application of remote sensing in precision Viticulture

This paper presents a study of precision agriculture in the wine industry. While precision viticulture mostly aims to maximise yields by delivering the right inputs to appropriate places on a farm in the correct doses and at the right time, the objective of this study was rather to assess vine biomass differences. The solution proposed in this paper uses aerial imagery as the primary source of data for vine analysis. The first objective to be achieved by the solution is to automatically identify vineyards blocks, vine rows, and individual vines within rows. This is made possible through a series of enhancements and hierarchical segmentations of the aerial images. The second objective is to determine the correlation of image data with the biophysical data (yield and pruning mass) of each vine. A multispectral aerial image is used to compute vegetation indices, which serve as indicators of biophysical measures. The results of the automatic detection are compared against a test field, to verify both vine location and vegetation index correlation with relevant vine parameters. The advantage of this technique is that it functions in environments where active cover crop growth between vines is evident and where variable vine canopy conditions are present within a vineyard block

Cement and fly ash stabilised gold mine tailings for the development of new material

Abstract: More than 500 gold tailings and a number of fly ash dumps exist in South Africa. These waste material contribute significantly to air, water and soil pollution. In this study gold mine tailings and fly ash which are readily available and result into environmental pollution were used to produce new building/construction material. The tailings were stabilised with cement and fly ash. Up to 20% of cement was incorporated in the mix design. The incorporation of 20% cement resulted into significant unconfined compressive strength (UCS) improvement of 3.89 MPa and 4.36 MPa at 56 and 90 days of curing, respectively. The strength development in fly ash and cement modified tailings was influenced by the pozzolanic and hydration reaction. The strength developed is applicable for the materials to be used for load bearing. The unconfined compressive strength of the developed specimen the composites met the minimum SANS 2001-CM1:2007 for hallow bricks to be used as masonry bricks

Enhancement of the geotechnical and geochemical properties of 1 gold tailings by BOF slag and class F fly ash

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A preliminary investigation of Nigerian Gmelina arborea and Bambusa vulgaris for pulp and paper production

Two common Nigerian-grown biomasses, gmelina (Gmelina arborea) and bamboo (Bambusaa vulgaris) have been pulped and their fibre characteristics and paper properties examined. The results of their chemical compositions showed some fair similarities. The amount of glucose in the pulps of bothbiomasses indicated their suitability as lignocellulosic materials for pulping. Their pulp yield ranged between 48,0-54,1%, which fell within the acceptable range for good pulpwoods. The analysis of their fibre dimensions revealed that bamboo fibre has a wider fibre length distribution and higher fine length content. Gmelina and bamboo had weighted mean fibre lengths of 0,93 and 2,07 mm and mean fibre widths of 24,1 and 16,9 μm, respectively. The Runkel ratios of the samples were 0,4 (gmelina) and 0,9(bamboo): this is indicative of their suitability for paper making. Mechanical properties of handsheets obtained from gmelina compared fairly well with South African pulpwoods (Eucalyptus grandis and Pinus paluta). Bamboo exhibited better tear index values than these woods but with lower sheet densityand tensile index. These properties were significantly improved in handsheets obtained from blends of gmelina and bamboo, raising the prospect of producing paper from blends of both raw materials inNigeria

DDX5 potentiates HIV-1 transcription as a co-factor of Tat

Funder: Cambridge Biomedical Research Centre (GB)Funder: Clinical Academic ReserveAbstract: Background: HIV-1 does not encode a helicase and hijacks those of the cell for efficient replication. We and others previously showed that the DEAD box helicase, DDX5, is an essential HIV dependency factor. DDX5 was recently shown to be associated with the 7SK snRNP. Cellular positive transcription elongation factor b (P-TEFb) is bound in an inactive form with HEXIM1/2 on 7SK snRNP. The Tat/P-TEFb complex is essential for efficient processivity of Pol II in HIV-1 transcription elongation and Tat competes with HEXIM1/2 for P-TEFb. We investigated the precise role of DDX5 in HIV replication using siRNA mediated knockdown and rescue with DDX5 mutants which prevent protein–protein interactions and RNA and ATP binding. Results: We demonstrate a critical role for DDX5 in the Tat/HEXIM1 interaction. DDX5 acts to potentiate Tat activity and can bind both Tat and HEXIM1 suggesting it may facilitate the dissociation of HEXIM1/2 from the 7SK-snRNP complex, enhancing Tat/P-TEFb availability. We show knockdown of DDX5 in a T cell line significantly reduces HIV-1 infectivity and viral protein production. This activity is unique to DDX5 and cannot be substituted by its close paralog DDX17. Overexpression of DDX5 stimulates the Tat/LTR promoter but suppresses other cellular and viral promoters. Individual mutations of conserved ATP binding, RNA binding, helicase related or protein binding motifs within DDX5 show that the N terminal RNA binding motifs, the Walker B and the glycine doublet motifs are essential for this function. The Walker A and RNA binding motifs situated on the transactivation domain are however dispensable. Conclusion: DDX5 is an essential cellular factor for efficient HIV transcription elongation. It interacts with Tat and may potentiate the availability of P-TEFb through sequestering HEXIM1

Secondary Distribution of HIV Self-Testing Kits to Social and Sexual Networks of PLWH in KwaZulu-Natal, South Africa. A Brief Report

Background: To reach 95% of persons living with HIV (PLWH) knowing their HIV status, alternative testing approaches such as HIV self-testing (HIVST) and secondary HIVST kit distribution are needed. We investigated if secondary HIVST kit distribution from male and female PLWH in South Africa would successfully lead to their contacts testing for HIV and linking to care if positive. / Methods: Male and female PLWH participating in an HIV treatment trial between July and November 2018 in KwaZulu-Natal, South Africa were offered participation as "HIVST kit distributors" in a pilot of secondary distribution of HIVST kits to give to sexual partners and social networks. Univariate descriptive statistics were used to describe the characteristics of volunteer distributors, proportion of HIVST recipients who reported their results, and linkage to care among those who tested positive using HIVST were assessed. / Results: Sixty-three participant kit distributors accepted kits to disperse to contacts, of whom 52% were female, median age was 34 years (IQR 26-42.5), 84% reported 1 sexual partner and 76% did not know their partner's HIV status. HIVST kit distributors took 218 kits, with 13/218 (6%) of kits reported to be intended to be given to a sexual partner. A total of 143 HIVST recipients reported their HIVST results; 92% reported their results were negative, 11 recipients reported positive results and 1 HIVST-positive recipient was linked to HIV care. / Conclusion: Secondary distribution of HIVST to social networks and sexual partners from South African PLWH is feasible, with two thirds of contacts reporting use of the HIVST kits. Additional support is necessary to facilitate linkage to care