Evidence for polarised boron in Co-B and Fe-B alloys

By exploiting the tunability of synchrotron radiation in measurements of spin-resolved photoemission it has proved possible to obtain information on the polarisation of the valence electrons of Co-B and Fe-B amorphous magnetic alloys, Both the spin-integrated and spin-resolved energy distribution curves show a marked dependence on photon energy indicating that the p states of boron hybridise with the d states of the transition metals giving rise to mixed states in the binding energy range 1 to 5 eV, The observed polarisation and spin-resolved densities of states imply that in the above restricted energy range there is a net negative polarisation of the boron states

The wonder years: what can primary school children teach us about immunity to Mycobacterium tuberculosis?

In high burden settings, the risk of infection with Mycobacterium tuberculosis increases throughout childhood due to cumulative exposure. However, the risk of progressing from tuberculosis (TB) infection to disease varies by age. Young children (<5 years) have high risk of disease progression following infection. The risk falls in primary school children (5 to <10 years), but rises again during puberty. TB disease phenotype also varies by age: generally, young children have intrathoracic lymph node disease or disseminated disease, while adolescents (10 to <20 years) have adult-type pulmonary disease. TB risk also exhibits a gender difference: compared to adolescent boys, adolescent girls have an earlier rise in disease progression risk and higher TB incidence until early adulthood. Understanding why primary school children, during what we term the “Wonder Years,” have low TB risk has implications for vaccine development, therapeutic interventions, and diagnostics. To understand why this group is at low risk, we need a better comprehension of why younger children and adolescents have higher risks, and why risk varies by gender. Immunological response to M. tuberculosis is central to these issues. Host response at key stages in the immunopathological interaction with M. tuberculosis influences risk and disease phenotype. Cell numbers and function change dramatically with age and sexual maturation. Young children have poorly functioning innate cells and a Th2 skew. During the “Wonder Years,” there is a lymphocyte predominance and a Th1 skew. During puberty, neutrophils become more central to host response, and CD4+ T cells increase in number. Sex hormones (dehydroepiandrosterone, adiponectin, leptin, oestradiol, progesterone, and testosterone) profoundly affect immunity. Compared to girls, boys have a stronger Th1 profile and increased numbers of CD8+ T cells and NK cells. Girls are more Th2-skewed and elicit more enhanced inflammatory responses. Non-immunological factors (including exposure intensity, behavior, and co-infections) may impact disease. However, given the consistent patterns seen across time and geography, these factors likely are less central. Strategies to protect children and adolescents from TB may need to differ by age and sex. Further work is required to better understand the contribution of age and sex to M. tuberculosis immunity

Ultrathin epitaxial Fe films in vicinal GaAs(001): A study by spin-resolved photoelectron spectroscopy

Thin epitaxial Fe films have been grown on vicinal GaAs(001) substrates and their remanent magnetic properties and the degree of substrate atom diffusion investigated using synchrotron-based photoelectron spectroscopy. The vicinal Fe films, though exhibiting greater As diffusion than their singular homologues, displayed better film quality both from the structural and the magnetic points of view. The spin-resolved valence spectra of the vicinal films resemble those for crystalline bulk Fe at lower film thicknesses than for singular films

Spin- and angle-resolved photoemission studies of the electronic structure of Si(110)"16x2" surfaces

The electronic structure of Si(110)"16 x 2" double-domain, single-domain and 1 x 1 surfaces have been investigated using spin- and angle-resolved photoemission at sample temperatures of 77 K and 300 K. Angle-resolved photoemission was conducted using horizontally- and vertically-polarised 60 eV and 80 eV photons. Band-dispersion maps revealed four surface states ($S_1$ to $S_4$) which were assigned to silicon dangling bonds on the basis of measured binding energies and photoemission intensity changes between horizontal and vertical light polarisations. Three surface states ($S_1$, $S_2$ and $S_4$), observed in the Si(110)"16 x 2" reconstruction, were assigned to Si adatoms and Si atoms present at the edges of the corrugated terrace structure. Only one of the four surface states, $S_3$, was observed in both the Si(110)"16 x 2" and 1 x 1 band maps and consequently attributed to the pervasive Si zigzag chains that are components of both the Si(110)"16 x 2" and 1 x 1 surfaces. A state in the bulk-band region was attributed to an in-plane bond. All data were consistent with the adatom-buckling model of the Si(110)"16 x 2" surface. Whilst room temperature measurements of $P_y$ and $P_z$ were statistically compatible with zero, $P_x$ measurements of the enantiomorphic A-type and B-type Si(110)"16 x 2" surfaces gave small average polarisations of around 1.5\% that were opposite in sign. Further measurements at 77 K on A-type Si(110)"16 x 2" surface gave a smaller value of +0.3\%. An upper limit of $\sim1\%$ may thus be taken for the longitudinal polarisation.Comment: Main paper: 12 pages and 11 figures. Supplemental information: 5 pages and 2 figure

Calculation of the Phase Behavior of Lipids

The self-assembly of monoacyl lipids in solution is studied employing a model in which the lipid's hydrocarbon tail is described within the Rotational Isomeric State framework and is attached to a simple hydrophilic head. Mean-field theory is employed, and the necessary partition function of a single lipid is obtained via a partial enumeration over a large sample of molecular conformations. The influence of the lipid architecture on the transition between the lamellar and inverted-hexagonal phases is calculated, and qualitative agreement with experiment is found.Comment: to appear in Phys.Rev.

UK guidelines for the management of soft tissue sarcomas

Soft tissue sarcomas (STS) are rare tumours arising in mesenchymal tissues, and can occur almost anywhere in the body. Their rarity, and the heterogeneity of subtype and location means that developing evidence-based guidelines is complicated by the limitations of the data available. However, this makes it more important that STS are managed by teams, expert in such cases, to ensure consistent and optimal treatment, as well as recruitment to clinical trials, and the ongoing accumulation of further data and knowledge. The development of appropriate guidance, by an experienced panel referring to the evidence available, is therefore a useful foundation on which to build progress in the field. These guidelines are an update of the previous version published in 2010 (Grimer et al. in Sarcoma 2010:506182, 2010). The original guidelines were drawn up following a consensus meeting of UK sarcoma specialists convened under the auspices of the British Sarcoma Group (BSG) and were intended to provide a framework for the multidisciplinary care of patients with soft tissue sarcomas. This current version has been updated and amended with reference to other European and US guidance. There are specific recommendations for the management of selected subtypes of disease including retroperitoneal and uterine sarcomas, as well as aggressive fibromatosis (desmoid tumours) and other borderline tumours commonly managed by sarcoma services. An important aim in sarcoma management is early diagnosis and prompt referral. In the UK, any patient with a suspected soft tissue sarcoma should be referred to one of the specialist regional soft tissues sarcoma services, to be managed by a specialist sarcoma multidisciplinary team. Once the diagnosis has been confirmed using appropriate imaging, plus a biopsy, the main modality of management is usually surgical excision performed by a specialist surgeon. In tumours at higher risk of recurrence or metastasis pre- or post-operative radiotherapy should be considered. Systemic anti-cancer therapy (SACT) may be utilized in some cases where the histological subtype is considered more sensitive to systemic treatment. Regular follow-up is recommended to assess local control, development of metastatic disease, and any late-effects of treatment. For local recurrence, and more rarely in selected cases of metastatic disease, surgical resection would be considered. Treatment for metastases may include radiotherapy, or systemic therapy guided by the sarcoma subtype. In some cases, symptom control and palliative care support alone will be appropriate

Human cytomegalovirus immunoglobulin G response and pulmonary tuberculosis in adolescents: a case-control study

Background Emerging evidence suggests a link between infection with herpes viruses, particularly human cytomegalovirus (HCMV) and Epstein Barr Virus (EBV), and progression to tuberculosis (TB) disease. Methods An unmatched case-control study was conducted amongst adolescents aged 10-19 years enrolled in an observational study (Teen TB), between November 2020 and November 2021, in Cape Town, South Africa. Fifty individuals with pulmonary TB and 51 healthy TB-exposed individuals without TB were included. Demographics and clinical data were obtained, and serum samples collected at enrolment were tested for HCMV IgG and EBV Nuclear Antigen (EBNA) IgG using two automated enzyme immunoassays. Odds ratios (ORs) were estimated using unconditional logistic regression. Results The median age of 101 participants was 15 years (interquartile range [IQR] 13 to 17); 55 (54%) were female. All participants were HCMV IgG seropositive and 95% were EBNA IgG seropositive. Individuals with TB had higher HCMV IgG titres than healthy controls (p=0.04). Individuals with upper tertile HCMV IgG titres had a 3.7 times greater odds of pulmonary TB compared to those with IgG titres in the lower tertile (95%CI: 1.05–12.84; p=0.04). There was a trend for increasing odds of pulmonary TB with increasing titres of HCMV IgG (p=0.04). In contrast, there was no association between TB and higher EBNA IgG values. Conclusions There is a high prevalence of sensitisation to HCMV and EBV amongst adolescents in this high-TB burden setting. Higher HCMV IgG titres were associated with pulmonary TB in adolescents

A review of methods for detecting rats at low densities, with implications for surveillance

Invasive rats are the biggest threat to island biodiversity world-wide. Though the ecological impacts of rats on insular biota are well documented, introduced rats present a difficult problem for detection and management. In recent decades, improved approaches have allowed for island-wide eradications of invasive rats on small-medium sized islands and suppression on large islands, although both these still represent a formidable logistical and financial challenge. A key aspect of eradication or suppression and ongoing management is the ability to detect the presence of rats, especially at low densities. Here we review recent developments in the field of rat surveillance and summarise current published literature to recommend practices and the factors to consider when developing a surveillance program for either eradication or suppression plans. Of 51 empirical studies covering 17 countries, 58% were from New Zealand. Although detecting rats at low density is extremely challenging, advances over the past 15 years, have significantly improved our ability to detect rats. Motion-sensored cameras and rodent detection dogs have greatly improved our ability to detect rats at low densities, with cameras consistently showing an ability to detect rats at lower densities than other techniques. Rodent detection dogs are also able to reliably detect even an individual rat, although there are challenges to their widespread adoption, particularly in developing countries, due to the cost and skills required for their training and maintenance. New monitoring devices, the use of eDNA and drones represent current and future innovations to improve detection