Determination of the total grain size distribution in a Vulcanian eruption column, and its implications to stratospheric aerosol perturbation

Grain size analysis of samples representing all sampleable portions of the airfall deposit produced by the Fuego volcano in Guatemala on 14 October 1974 form the basis for estimating the total grain size distribution of tephra from this eruption. The region enclosed by each isopach has a particular average grain size distribution which can be weighted proportionally to its percentage volume. The grain size of pyroclastic avalanche deposits produced during the eruption are also included. The total grain size distribution calculated as a sum of weighted distributions has a median grain size of 0.8∅ (0.6mm) and a sorting coefficient (σ∅) of 2.3. The size distribution seems to approximate Rosin and Rammler\u27s law of crushing and this observation allows us to estimate that no more than 15% volume of the fine tail of the total size distribution is likely to be missing. The ash composed of these fine particles did not fall in the region of the volcano as part of the recognizable tephra blanket. The eruption column reached well into the stratosphere: heights estimated from the ground were 10-12 km above sea level but estimated heights based on mass flux rates are higher (18-23 km). The proportion of ash smaller than 2 µm, which could remain for substantial periods in the stratosphere, is no more than 0.8% volume of the total. It seems probable that acid aerosol particles from vulcanian type eruptions are more important to stratospheric aerosol perturbation than fine silicate ash particles by at least an order of magnitude

The Murrow Legend as Metaphor: The Creation, Appropriation, and Usefulness of Edward R. Murrow\u27s Life Story

Gary Edgerton\u27s contribution to the Journal of American Culture, Vol. 15

Harvests of shame: enduring unfree labour in twentieth century United States, 1933-1964

This article reframes the discussion on vulnerable and exploited agricultural labour in twentieth-century United States using the overarching category of unfree labour. In order to do so, it bridges two usually distinct historiographies by linking the phenomenon of ‘peonage’ during the New Deal, with the one of immigrant contract labour southern Florida, under the H2 visa. Archival research on the practices at the US Sugar Corporation in southern Florida exemplifies this link. This article draws on federal archives, government proceedings, papers of political activists and legal and labour scholarship to argue: firstly, that unfree labour has been an enduring feature of agricultural labour relations at regional level during the twentieth century, through both a transmission and a transformation of practice that had their origin in the control of black emancipated labour; secondly, that the introduction of guest workers under the H2 and Bracero programme meant a modernization in the practices of unfree labour, pivoting on the lack of citizenship rights, racial discrimination, debt at home, and threat of deportation; and, finally, that the failure to recognise forms of legal and economic deprivation and coercion as unfree labour has hurt the ability of the United States to enforce protection of human rights at home

A multicentre, randomised controlled trial to compare the clinical and cost-effectiveness of Lee Silverman Voice Treatment versus standard NHS Speech and Language Therapy versus control in Parkinson’s disease: a study protocol for a randomised controlled trial

Abstract: Background: Parkinson’s disease (PD) affects approximately 145,519 people in the UK. Speech impairments are common with a reported prevalence of 68%, which increase physical and mental demands during conversation, reliance on family and/or carers, and the likelihood of social withdrawal reducing quality of life. In the UK, two approaches to Speech and Language Therapy (SLT) intervention are commonly available: National Health Service (NHS) SLT or Lee Silverman Voice Treatment (LSVT LOUD®). NHS SLT is tailored to the individuals’ needs per local practice typically consisting of six to eight weekly sessions; LSVT LOUD® comprises 16 sessions of individual treatment with home-based practice over 4 weeks. The evidence-base for their effectiveness is inconclusive. Methods/design: PD COMM is a phase III, multicentre, three-arm, unblinded, randomised controlled trial. Five hundred and forty-six people with idiopathic PD, reporting speech or voice problems will be enrolled. We will exclude those with a diagnosis of dementia, laryngeal pathology or those who have received SLT for speech problems in the previous 2 years. Following informed consent and completion of baseline assessments, participants will be randomised in a 1:1:1 ratio to no-intervention control, NHS SLT or LSVT LOUD® via a central computer-generated programme, using a minimisation procedure with a random element, to ensure allocation concealment. Participants randomised to the intervention groups will start treatment within 4 (NHS SLT) or 7 (LSVT LOUD®) weeks of randomisation. Primary outcome: Voice Handicap Index (VHI) total score at 3 months. Secondary outcomes include: VHI subscales, Parkinson’s Disease Questionnaire-39; Questionnaire on Acquired Speech Disorders; EuroQol-5D-5 L; ICECAP-O; resource utilisation; adverse events and carer quality of life. Mixed-methods process and health economic evaluations will take place alongside the trial. Assessments will be completed before randomisation and at 3, 6 and 12 months after randomisation. The trial started in December 2015 and will run for 77 months. Recruitment will take place in approximately 42 sites around the UK. Discussion: The trial will test the hypothesis that SLT is effective for the treatment of speech or voice problems in people with PD compared to no SLT. It will further test whether NHS SLT or LSVT LOUD® provide greater benefit and determine the cost-effectiveness of both interventions. Trial registration: International Standard Randomised Controlled Trials Number (ISRCTN) Registry, ID: 12421382. Registered on 18 April 2016

A multicentre, randomised controlled trial to compare the clinical and cost-effectiveness of Lee Silverman Voice Treatment versus standard NHS Speech and Language Therapy versus control in Parkinson’s disease: a study protocol for a randomised controlled trial

Abstract: Background: Parkinson’s disease (PD) affects approximately 145,519 people in the UK. Speech impairments are common with a reported prevalence of 68%, which increase physical and mental demands during conversation, reliance on family and/or carers, and the likelihood of social withdrawal reducing quality of life. In the UK, two approaches to Speech and Language Therapy (SLT) intervention are commonly available: National Health Service (NHS) SLT or Lee Silverman Voice Treatment (LSVT LOUD®). NHS SLT is tailored to the individuals’ needs per local practice typically consisting of six to eight weekly sessions; LSVT LOUD® comprises 16 sessions of individual treatment with home-based practice over 4 weeks. The evidence-base for their effectiveness is inconclusive. Methods/design: PD COMM is a phase III, multicentre, three-arm, unblinded, randomised controlled trial. Five hundred and forty-six people with idiopathic PD, reporting speech or voice problems will be enrolled. We will exclude those with a diagnosis of dementia, laryngeal pathology or those who have received SLT for speech problems in the previous 2 years. Following informed consent and completion of baseline assessments, participants will be randomised in a 1:1:1 ratio to no-intervention control, NHS SLT or LSVT LOUD® via a central computer-generated programme, using a minimisation procedure with a random element, to ensure allocation concealment. Participants randomised to the intervention groups will start treatment within 4 (NHS SLT) or 7 (LSVT LOUD®) weeks of randomisation. Primary outcome: Voice Handicap Index (VHI) total score at 3 months. Secondary outcomes include: VHI subscales, Parkinson’s Disease Questionnaire-39; Questionnaire on Acquired Speech Disorders; EuroQol-5D-5 L; ICECAP-O; resource utilisation; adverse events and carer quality of life. Mixed-methods process and health economic evaluations will take place alongside the trial. Assessments will be completed before randomisation and at 3, 6 and 12 months after randomisation. The trial started in December 2015 and will run for 77 months. Recruitment will take place in approximately 42 sites around the UK. Discussion: The trial will test the hypothesis that SLT is effective for the treatment of speech or voice problems in people with PD compared to no SLT. It will further test whether NHS SLT or LSVT LOUD® provide greater benefit and determine the cost-effectiveness of both interventions. Trial registration: International Standard Randomised Controlled Trials Number (ISRCTN) Registry, ID: 12421382. Registered on 18 April 2016

Nasopharyngeal versus Oropharyngeal Sampling for Detection of Pneumococcal Carriage in Adults

Several studies have shown that nasopharyngeal sampling is more sensitive than oropharyngeal sampling for the detection of pneumococcal carriage in children. The data for adults are limited and conflicting. This study was part of a larger study of pneumococcal carriage on the Navajo and White Mountain Apache Reservation following a clinical trial of a seven-valent pneumococcal conjugate vaccine. Persons aged 18 years and older living in households with children enrolled in the vaccine trial were eligible. We collected both nasopharyngeal and oropharyngeal specimens by passing a flexible calcium alginate wire swab either nasally to the posterior nasopharynx or orally to the posterior oropharynx. Swabs were placed in skim milk-tryptone-glucose-glycerin medium and frozen at −70°C. Pneumococcal isolation was performed by standard techniques. Analyses were based on specimens collected from 1,994 adults living in 1,054 households. Nasopharyngeal specimens (11.1%; 95% confidence interval [CI], 9.8 and 12.6%) were significantly more likely to grow pneumococci than were oropharyngeal specimens (5.8%; 95% CI, 4.8 to 6.9%) (P < 0.0001). Few persons had pneumococcal growth from both specimens (1.7%). Therefore, both tests together were more likely to identify pneumococcal carriage (15.2%; 95% CI, 13.7 to 16.9%) than either test alone. Although we found that nasopharyngeal sampling was more sensitive than oropharyngeal sampling, nasopharyngeal sampling alone would have underestimated the prevalence of pneumococcal carriage in this adult population. Sampling both sites may give more accurate results than sampling either site alone in studies of pneumococcal carriage in adults