Collisional depolarisation of rotational angular momentum in the OH Radical

Polarisation Spectroscopy (PS) has been used as a novel approach for measuring the collisional removal of bulk rotational orientation and alignment in OH (X 2Π3/2, v = 0, j = 1.5 – 6.5, e) and OH (A 2Σ+, v = 1, N = 1 – 5, f1). Both one-colour degenerate PS (OCPS) and two-colour PS (TCPS) have been exploited. TCPS provides a route to measuring thermal rate constants (298 K) for the collisional evolution of rotational polarisations in unique rotational quantum states. For OH (X), the dependence on the decay of the PS signal was investigated with a number of collision partners: He, Ar, Xe N2 and O2. The ability to remove PS signals increases across the series of noble gases He < Ar < Xe. In all cases the measured rate constant for loss of alignment is larger than that for orientation. This provides conclusive evidence that elastic depolarisation (the elastic redistribution of mj-sublevels) contributes to the loss of PS signals. The efficiency of this contribution is found to be modest for He, but significant for Ar and Xe. Comparison of the PS measurements with quantum scattering calculations assists in the evaluation of the magnitude of elastic depolarisation for the atomic partners and also provides a rigorous test of the potential energy surfaces describing their interaction. Intriguing differences are found between the kinematically similar N2 and O2. A detailed cross comparison between colliders, comparison of the measurements to the potential energy surface and independent theoretical work suggest that the weaker long-range attractive forces play a significant role in elastic depolarisation. The dynamics of OH (A) was measured with He and Ar only. PS experiments were compared to independent experimental and theoretical work carried out in parallel to this research. Distinctively different j-dependent trends for the removal of bulk rotational polarisations are observed for OH (X) + Ar and OH (A) + Ar. This comparative study emphasises the role of the attractive limbs of the potential energy surface in mediating elastic depolarisation

Actinobaculum schaalii: An Emerging Uropathogen?

A. schaalii is a rare uropathogen. We report urosepsis with Actinobaculum schaalii detected serendipitously in blood and urine culture in a 79-year-old with urinary tract obstruction. This paper illuminates the flaws in our current system in detecting A. schaalii and raises awareness among clinicians and laboratory teams

Mutagens affect food and water biodeteriorating fungi

Many areas of food mycology could be affected detrimentally by mutation of wild type fungi. Some of these will contact mutagens from pre-isolation to experimentation and the effect on fungi isolated from mycotoxin-contaminated food is assessed for the first time in this review. However, this mutagen issue is not considered by other authors in primary research papers, which is relevant to molecular biology techniques for gene sequencing, phylogenetics, diagnostics and mycotoxin production. The presence of mutagens is anathema to methods for DNA analysis at the experimental design level and concepts such as cryptic species and correlating anamorphs with teleomorphs are affected. Strains held in culture collections may be artifacts. Methods to ameliorate the problem are provided herein.FCT Strategic Project of UID/BIO/04469/2013 unit, the project RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-FEDER-027462) and the project ‘‘BioInd - Biotechnology and Bioengineering for improved Industrial and Agro-Food processes’’, REF. NORTE-07-0124-FEDER- 000028 Co-funded by the Programa Operacional Regional do Norte (ON.2 – O Novo Norte), QREN, FEDER

Rapid detection of Ganoderma-infected oil palms by microwave ergosterol extraction with HPLC and TLC

Detection of basal stem rot (BSR) by Ganoderma of oil palms was based on foliar symptoms and production of basidiomata. Enzyme-Linked Immunosorbent Assays-Polyclonal Antibody (ELISA-PAB) and PCR have been proposed as early detection methods for the disease. These techniques are complex, time consuming and have accuracy limitations. An ergosterol method was developed which correlated well with the degree of infection in oil palms, including samples growing in plantations. However, the method was capable of being optimised. This current study was designed to develop a simpler, more rapid and efficient ergosterol method with utility in the field that involved the use of microwave extraction. The optimised procedure involved extracting a small amount of Ganoderma, or Ganoderma-infected oil palm suspended in low volumes of solvent followed by irradiation in a conventional microwave oven at 70 °C and medium high power for 30 s, resulting in simultaneous extraction and saponification. Ergosterol was detected by thin layer chromatography (TLC) and quantified using high performance liquid chromatography with diode array detection. The TLC method was novel and provided a simple, inexpensive method with utility in the field. The new method was particularly effective at extracting high yields of ergosterol from infected oil palm and enables rapid analysis of field samples on site, allowing infected oil palms to be treated or culled very rapidly. Some limitations of the method are discussed herein. The procedures lend themselves to controlling the disease more effectively and allowing more effective use of land currently employed to grow oil palms, thereby reducing pressure to develop new plantations.This project was supported by the Fundamental Research Grant Scheme (FRGS), administered through the Ministry of Higher Education, Malaysia (Grant No: 5524175)

Prioritisation of potential agents for the biological control of the invasive alien weed, Pereskia aculeata (Cactaceae), in South Africa

Pereskia aculeata Miller (Cactaceae) is an invasive alien species in South Africa that is native in Central and South America. In South Africa, P. aculeata outcompetes native plant species leading to a reduction in biodiversity at infested sites. Herbicidal and mechanical control of the plant is ineffective and unsustainable, so biological control is considered the only potential solution. Climatic matching and genotype matching indicated that the most appropriate regions in which to collect biological control agents were Santa Catarina and Rio de Janeiro provinces in Southern Brazil. Surveys throughout the native distribution resulted in 15 natural enemy species that were associated with the plant. Field host range data, as well as previous host plant records, were used to prioritise which of the species were most likely to be suitably host specific for release in South Africa. The mode of damage was used to determine which species were most likely to be damaging and effective if released. The most promising species prioritised for further study, including host specificity and impact studies, were the stem-wilter Catorhintha schaffneri Brailovsky and Garcia (Coreidae); the stem boring species Acanthodoxus machacalis Martins and Monné (Cerambycidae), Cryptorhynchus sp. (Curculionidae) and Maracayia chlorisalis (Walker) (Crambidae) and the fruit galler Asphondylia sp. (Cecidomyiidae). By prioritising the potential biological control agents that are most likely to be host-specific and damaging, the risk of conducting host specificity testing on unsuitable or ineffective biological control agents is reduced

Structural Racism in the United States: A Report to the U.N. Committee for the Elimination of Racial Discrimination on the occasion of its review of the Periodic Report of the United States of America

As a signatory to the Convention on the Elimination of Racial Discrimination (CERD), 1 the United States is under an obligation to condemn and pursue a policy of eliminating racial discrimination, in all its forms (art. 2, ¶1). The U.S. has not taken seriously the duty under Article 2 of CERD to affirmatively address racial discrimination. Instead, the U.S. has rationalized racial discriminatory effects as not covered by U.S. law. Sometimes these effects are caused by explicit government polices. At other times they are caused by private actors. Frequently, it is a combination of both. The Convention defines racial discrimination (art. 1, ¶1) to mean distinctions, exclusions, restrictions or preferences based on race which have “the purpose or effect” of nullifying or impairing the recognition, enjoyment or exercise, on an equal footing, of human rights and fundamental freedoms in any field of public life. CERD’s definition of discrimination is unequivocal: effects and racially disparate outcomes caused by individual action or government practices or policies, singularly or collectively, are of primary concern. Contrary to CERD, U.S. law defines racial discrimination more narrowly in at least two critical respects. First, with few exceptions U.S. law narrowly defines cognizable racial discrimination by requiring evidence of intent to discriminate. Section II demonstrates that such a requirement is contrary to the framework of CERD and does not reflect the real-world operation of discriminatory behavior in contemporary American society

Liquid crystal dimers and the twist-bend nematic phase: on the role of spacers and terminal alkyl chains.

The synthesis and characterisation of four series of liquid crystal dimers based on benzylideneaniline mesogenic units, and in which the lengths of terminal alkyloxy chains are varied are reported. The series differ in terms of their flexible spacers, namely, heptamethylene, nonamethylene, hexyloxy, and oxypentyloxy chains. The heptamethylene- and nonamethylene-linked dimers both show conventional nematic, N, and twist-bend nematic, NTB, phases with short terminal chains, and smectic behaviour emerges on increasing terminal chain length. This is attributed to increased molecular inhomogeneity driving microphase separation. The dimers containing the shorter heptamethylene spacer show a smectic A phase whereas those with the longer nonamethylene spacer exhibit an anticlinic smectic C phase. Smectic behaviour is not observed for the dimers containing either a hexyloxy spacer which exhibit nematic and twist-bend nematic phases, or with an oxypentyloxy spacer which show only a conventional nematic phase. A general observation is that TNTBN and TNI alternate in the same sense in a homologous series on varying the length of the terminal alkyl chains suggesting that the spatial uniformity of the molecular curvature is an important factor in stabilising the NTB phase. The transitional properties of the four corresponding dimers possessing nitrile terminal substituents are also described. These show enantiotropic nematic phases, and in addition, for those containing either polymethylene or hexyloxy spacers, a twist-bend nematic phase is observed. Differences in the thermal behaviour of the dimers may be attributed largely to changes in molecular shape arising from the nature of the link between the spacer and mesogenic units

Influenza Vaccine Effectiveness against Hospitalisation with Confirmed Influenza in the 2010-11 Seasons: A Test-negative Observational Study

Immunisation programs are designed to reduce serious morbidity and mortality from influenza, but most evidence supporting the effectiveness of this intervention has focused on disease in the community or in primary care settings. We aimed to examine the effectiveness of influenza vaccination against hospitalisation with confirmed influenza. We compared influenza vaccination status in patients hospitalised with PCR-confirmed influenza with patients hospitalised with influenza-negative respiratory infections in an Australian sentinel surveillance system. Vaccine effectiveness was estimated from the odds ratio of vaccination in cases and controls. We performed both simple multivariate regression and a stratified analysis based on propensity score of vaccination. Vaccination status was ascertained in 333 of 598 patients with confirmed influenza and 785 of 1384 test-negative patients. Overall estimated crude vaccine effectiveness was 57% (41%, 68%). After adjusting for age, chronic comorbidities and pregnancy status, the estimated vaccine effectiveness was 37% (95% CI: 12%, 55%). In an analysis accounting for a propensity score for vaccination, the estimated vaccine effectiveness was 48.3% (95% CI: 30.0, 61.8%). Influenza vaccination was moderately protective against hospitalisation with influenza in the 2010 and 2011 seasons

An introduction to the fourth decadal review of biological control of invasive alien plants in South Africa (2011–2020)

This special issue is the fourth decadal review of biological control of invasive alien plants (biocontrol of weeds) in South Africa, following those published in 1991, 1999 and 2011. Including this introduction, there are 24 papers covering the weed biocontrol programmes, or important developments in the science and practice, from the period 2011-2020. Seventy-two target weed species are covered, including 25 species on which projects were initiated during the past decade. Developments in regulations, mass-rearing and implementation, and community engagement are also reviewed. An updated catalogue of agents released, rejected and under consideration is presented and reflects the most recent methods of quantifying success in weed biocontrol. Key events over the last decade include the hosting of the XIV International Symposium on Biological Control of Weeds to celebrate 100 years of weed biocontrol in South Africa, as well as the establishment of the Centre for Biological Control at Rhodes University. The science and practice of weed biocontrol has expanded significantly in the past decade, with growth in the number of researchers and practitioners, increased funding, and an increased number of scholarly outputs. Unlike many other countries in the world, South Africa has largely avoided constraints due to restrictive and risk averse legislation and bureaucracy, and has continued to release new biocontrol agents at a similar rate to that in previous years. Much of the success of weed biocontrol in South Africa is due to the sustained and increasing support of the Natural Resource Management Programme of the Department of Forestry, Fisheries and the Environment (Working for Water Programme). However, gaps in funding, where no funds are available for months at a time, are a major concern as the weed biocontrol community loses human capital in these periods, and research programmes suffer significant set-backs. Weed biocontrol is an essential component of South Africa’s strategy to reduce the negative impacts of invasive alien plants and has contributed significantly towards the protection of the country’s ecosystems, indigenous biodiversity, water security, agricultural productivity, and society in general. If the trend of increasing support for weed biocontrol in South Africa continues, we can expect that the benefits for the country at large will increase substantially in the future