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1.
J Environ Manage ; 304: 114264, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34906809

RESUMO

Enhanced efficiency fertilisers (EEF) may reduce nitrogen (N) losses and improve uptake efficiency through synchronising N release with in-season plant requirements. We hypothesised that EEF formed via matrix encapsulation in biodegradable polymers will improve N use efficiency when compared to conventional urea fertiliser. This hypothesis was investigated for two biodegradable polymer matrices: polyhydroxyalkanoate (PHA), containing 11.6% urea (by mass), and polybutylene-adipate-co-terephthalate (PBAT), containing either 19.4 or 32.7% urea; and two contrasting soil types: sand and clay. Nitrogen availability and form was investigated under leaching conditions (water) with a growth accelerator pot experiment involving a horticultural crop and novel non-destructive three-dimensional scanning to measure in-season biomass development. The PBAT 32.7% formulation enabled greater above ground biomass production at both 50 and 100 kg N ha-1 equivalent application rates compared to conventional urea. For the sandy soil, plant scanning indicated that improved uptake performance with PBAT 32.7% was probably the result of greater N availability after 25 days than for conventional urea. Two of the encapsulated formulations (PHA and PBAT 19.4%) tended to decrease nitrogen leaching losses relative to urea (P < 0.05 for the red clay soil). However, decreased N leaching loss was accompanied by poorer N uptake performance, indicative of N being less available in these biopolymer formulations. A snapshot of nitrous oxide emissions collected during peak nitrate concentration (prior to planting and leaching) suggested that the biopolymers promoted N loss via gaseous emission relative to urea in the sandy soil (P < 0.05), and carbon dioxide emissions data suggested that biopolymer-carbon increased microbial activity (P < 0.1). Controlled testing of N release in water was a poor predictor of biomass production and leaching losses. The diverse behaviours of the tested formulations present the potential to optimise biopolymers and their N loadings by taking into account soil and environmental factors that influence the efficient delivery of N to target crops. The greater N uptake efficiency demonstrated for the PBAT 32.7% formulation confirms our hypothesis that matrix encapsulation can enable better synchronisation of N release with crop requirements and decrease leaching losses.


Assuntos
Fertilizantes , Objetivos , Agricultura , Produtos Agrícolas , Fertilizantes/análise , Nitrogênio/análise , Polímeros , Solo
2.
Opt Express ; 27(8): 11819-11829, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-31053022

RESUMO

We experimentally demonstrate an aggregate 86-GBaud (over three sub-bands and one polarization) signal generation based on subcarrier multiplexing technique using IQ mixers, an electrical 90 degree hybrid, and diplexers. The electrical hybrid allows transmitter-side digital signal processing to be simplified to pulse shaping and digital pre-emphasis. We verified the configuration by testing the performance of an 86-GBaud Nyquist-shaped 16 quadrature amplitude modulation signal with differential bit encoding. The implementation penalty assuming 7% hard-decision forward error correction is reduced to 2 dB by utilizing a 31-tap decision-directed least mean square based multiple-input multiple-output equalizer for sideband crosstalk mitigation.

3.
J Chem Phys ; 151(24): 244107, 2019 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-31893867

RESUMO

A means of unifying some semiclassical models of computational chemistry is presented; these include quantized Hamiltonian dynamics, quantal cumulant dynamics, and semiclassical Moyal dynamics (SMD). A general method for creating the infinite hierarchy of operator dynamics in the Heisenberg picture is derived together with a general method for truncation (or closure) of that series, and in addition, we provide a simple link to the phase space methods of SMD. Operator equations of arbitrary order may be created readily, avoiding the tedious algebra identified previously. Truncation is based on a simple recurrence formula which is related to, but avoids the more complex contractions of, Wick's theorem. This generalized method is validated against a number of trial problems considered using the previous methods. We also touch on some of the limitations involved using such methods, noting, in particular, that any truncation will lead to a state which is in some sense unphysical. Finally, we briefly introduce our quantum algebra package QuantAL which provides an automated method for the generation of the required equation set, the initial conditions for all variables from any start, and all the higher order approximations necessary for truncation of the series, at essentially arbitrary order.

4.
Br J Cancer ; 117(7): 925-931, 2017 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-28797032

RESUMO

BACKGROUND: One-third of new early breast cancer diagnoses occur in women over 70 years old. However, older women are less likely to receive radical curative treatments. This study prospectively evaluated a cohort of older women using a Comprehensive Geriatric Assessment (CGA) to determine whether fitness explained the apparent under-treatment in this patient group. METHODS: In this multi-centre prospective study, patients aged ⩾70 years with Stages I-III breast cancer underwent a pretreatment baseline CGA consisting of eight assessment tools. Patients were defined as 'fit' if they had normal score in seven out of eight of the assessment tools. 'High risk' patients were defined as those with grade 3, ER negative, HER2 positive, or node positive breast cancer. RESULTS: Data on 326 patients were available for full analysis. The median age was 77 years. In all, 182 (56%) of the total population were defined as high risk, with 49%, 61% and 53% of those in the 70-74, 75-84 and ⩾85 years age groups respectively having high risk tumours. A total of 301 patients had sufficient CGA records of whom 131 (44%) were reported as fit, with 34%, 54% and 12% of them in the 70-74, 75-84 and ⩾85 years age groups respectively. More fit than unfit patients underwent primary breast surgery (100% vs 91%, P=0.0002), axillary surgery (92% vs 84%, P=0.0340), and adjuvant chemotherapy for high-risk disease (51% vs 20%, P=0.0001). Rates of adjuvant radiotherapy after wide local excision were not significantly different (88% vs 90% respectively, P=0.8195). CONCLUSIONS: In this study, all women ⩾70 years deemed fit by CGA underwent primary surgery. Nearly 50% of fit women with high-risk disease did not receive adjuvant chemotherapy suggesting under treatment in this group.


Assuntos
Neoplasias da Mama/terapia , Quimioterapia Adjuvante/estatística & dados numéricos , Avaliação Geriátrica , Mastectomia/estatística & dados numéricos , Radioterapia Adjuvante/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Neoplasias da Mama/química , Neoplasias da Mama/patologia , Feminino , Mau Uso de Serviços de Saúde , Humanos , Metástase Linfática , Estudos Prospectivos , Receptor ErbB-2/análise , Receptores de Estrogênio/análise , Medição de Risco
5.
Opt Express ; 24(15): 16649-58, 2016 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-27464119

RESUMO

A black box phase sensitive amplifier based 3R regeneration scheme is proposed for non-return to zero quadrature phase shift keyed formatted signals. Performance improvements of more than 2 dB are achieved at the presence of input phase distortion.

6.
Opt Express ; 24(3): 2215-21, 2016 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-26906797

RESUMO

We demonstrate that a distributed Raman amplification scheme based on random distributed feedback (DFB) fiber laser enables bidirectional second-order Raman pumping without increasing relative intensity noise (RIN) of the signal. This extends the reach of 10 × 116 Gb/s DP-QPSK WDM transmission up to 7915 km, compared with conventional Raman amplification schemes. Moreover, this scheme gives the longest maximum transmission distance among all the Raman amplification schemes presented in this paper, whilst maintaining relatively uniform and symmetric signal power distribution, and is also adjustable in order to be highly compatible with different nonlinearity compensation techniques, including mid-link optical phase conjugation (OPC) and nonlinear Fourier transform (NFT).

7.
Opt Express ; 23(2): 902-11, 2015 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-25835850

RESUMO

We experimentally demonstrate a Raman-Assisted Fibre Optical Parametric Amplifier (RA-FOPA) with 20dB net gain using wavelength division multiplexed signals. We report amplification of 10x58Gb/s 100GHz-spaced QPSK signals and show that by appropriate tuning of the parametric pump power and frequency, gain improvement of up to 5dB can be achieved for the RA-FOPA compared with combined individual contributions from the parametric and Raman pumps. We compare the RA-FOPA with an equivalent-gain conventional FOPA and find that four-wave mixing crosstalk is substantially reduced by up to 5.8 ± 0.4dB using the RA-FOPA. Worst-case performance penalty of the RA-FOPA is found to be only 1.0 ± 0.2dB over all measured OSNRs, frequencies and input powers, making it an attractive proposal for future communications systems.

8.
Opt Express ; 22(10): 11840-8, 2014 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-24921305

RESUMO

Optical phase conjugation (OPC) of a polarization-multiplexed comb of 10x114Gb/s DP-QPSK signals has been demonstrated for the first time, occupying a spectral bandwidth of >1 THz (~9 nm). The nonlinear element employed for the OPC was highly nonlinear fiber (HNLF) optimized for the suppression of stimulated Brillouin scattering (SBS) and configured in a bi-directional loop offering polarization diversity. Pump power (each way about the loop) and input signal power to the OPC subsystem were optimized at 29.7 dBm and + 3 dBm respectively producing a Q(2) penalty of ≤ 0.9 dB over all conjugate wavelengths, polarizations and output OSNR (up to 20 dB).

9.
Nat Genet ; 17(4): 491-4, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9398858

RESUMO

Individuals with primary trimethylaminuria exhibit a body odour reminiscent of rotting fish, due to excessive excretion of trimethylamine (TMA; refs 1-3). The disorder, colloquially known as fish-odour syndrome, is inherited recessively as a defect in hepatic N-oxidation of dietary-derived TMA and cannot be considered benign, as sufferers may display a variety of psychosocial reactions, ranging from social isolation of clinical depression and attempted suicide. TMA oxidation is catalyzed by flavin-containing mono-oxygenase (FMO; refs 7,8), and tissue localization and functional studies have established FMO3 as the form most likely to be defective in fish-odour syndrome. Direct sequencing of the coding exons of FMO3 amplified from a patient with fish-odour syndrome identified two missense mutations. Although one of these represented a common polymorphism, the other, a C-->T transition in exon 4, was found only in an affected pedigree, in which it segregated with the disorder. The latter mutation predicts a proline-->leucine substitution at residue 153 and abolishes FMO3 catalytic activity. Our results indicate that defects in FMO3 underlie fish-odour syndrome and that the Pro 153-->Leu 153 mutation described here is a cause of this distressing condition.


Assuntos
Erros Inatos do Metabolismo/enzimologia , Metilaminas/urina , Mutação , Odorantes , Oxigenases/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Humanos , Erros Inatos do Metabolismo/genética , Dados de Sequência Molecular , Oxirredução , Linhagem , Síndrome
10.
J Environ Manage ; 95(1): 29-38, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22115508

RESUMO

The effects of addition of carbonated residue mud (RMC) or seawater neutralized residue mud (RMS), at two rates, in the presence or absence of added green waste compost, on the chemical, physical and microbial properties of gypsum-treated bauxite residue sand were studied in a laboratory incubation study. The growth of two species commonly used in revegetation of residue sand (Lolium rigidum and Acacia saligna) in the treatments was then studied in a 18-week greenhouse study. Addition of green waste-based compost increased ammonium acetate-extractable (exchangeable) Mg, K and Na. Addition of residue mud at 5 and 10% w/w reduced exchangeable Ca but increased that of Mg and Na (and K for RMS). Concentrations of K, Na, Mg and level of EC in saturation paste extracts were increased by residue mud additions. Concentrations of cations in water extracts were considerably higher than those in saturation paste extracts but trends with treatment were broadly similar. Addition of both compost and residue mud caused a significant decrease in macroporosity with a concomitant increase in mesoporosity and microporosity, available water holding capacity and the quantity of water held at field capacity. Increasing rates of added residue mud reduced the percentage of sample present as discrete sand particles and increased that in aggregated form (particularly in the 1-2 and >10mm diameter ranges). Organic C content, C/N ratio, soluble organic C, microbial biomass C and basal respiration were increased by compost additions. Where compost was added, residue mud additions caused a substantial increase in microbial biomass and basal respiration. L. rigidum grew satisfactorily in all treatments although yields tended to be reduced by additions of mud (especially RMC) particularly in the absence of added compost. Growth of A. saligna was poor in sand alone and mud-amended sand and was greatly promoted by additions of compost. However, in the presence of compost, addition of carbonated mud had a marked depressive effect on both top and root growth. The significant positive effect of compost was attributed to substantial inputs of K and marked reductions in the Na/K ratio in soil solution while the depressive effect of RMC was attributed to its greater alkalinity and consequently higher concentrations of HCO(3)(-) in solution.


Assuntos
Óxido de Alumínio , Germinação , Solo/química , Acacia/crescimento & desenvolvimento , Lolium/crescimento & desenvolvimento , Compostos Orgânicos/análise , Microbiologia do Solo
11.
Sci Total Environ ; 804: 150134, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34509849

RESUMO

Establishing a sustainable vegetation cover is one of the most important steps in progressive rehabilitation and final closure of ore-processing residues and tailings facilities. Sustainable rehabilitation partly depends on establishing and maintaining a supply of plant-available nutrients, but few long term field studies demonstrating the success or failure of rehabilitation of degraded land such as mineral processing tailings have been reported. Bauxite-processing residues are a highly sodic, highly alkaline, nutrient-poor by-product generated from alumina extraction, and pose many challenges for successful rehabilitation. This study investigated long term performance of rehabilitation established on bauxite-processing residue storage areas (RSAs) by comparing the nutrient content of the vegetation cover with nutrient concentrations in the underlying residue sand. Five plant species having diverse physiology were selected from rehabilitation varying in age from 1 to 10 years old; these being: Hardenbergia comptoniana - a vigorous growing legume ground cover/creeper), Acacia cochlearis and A. rostellifera - legume shrubs tolerant of sandy, alkaline conditions, Grevillea crithmifolia - a drought-tolerant proteaceous shrub tolerant of alkaline soil, and Spyridium globulosum - a robust, fast-growing shrub, commonly found on alkaline coastal soils. Gypsum incorporation reduced the pH and soluble aluminium levels in residue sand, but also acted as a long-term source of nutrients for the vegetation cover. Legume species contained more nitrogen than non-legumes (2.5% N and 1.5% N, respectively), and decomposition of surface litter increased organic carbon and total and mineral nitrogen contents of the residue sand over time. Nutrient cycling maintained a supply of macro- and micro- nutrients for the vegetation cover, and 10-year old rehabilitation exhibited characteristics similar to an analogue site. This study highlighted the importance of organic matter accumulation, developing a functional microbial community, and a diverse plant species mix on transforming the residue sand characteristics and encouraging nutrient cycling as key mechanisms for establishing a sustainable vegetation cover and functional ecosystem on residue sand embankments.


Assuntos
Óxido de Alumínio , Ecossistema , Nitrogênio/análise , Nutrientes , Solo
12.
ESMO Open ; 7(2): 100445, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35398717

RESUMO

INTRODUCTION: Pembrolizumab is an established first-line option for patients with advanced non-small-cell lung cancer (NSCLC) expressing programmed death-ligand 1 ≥50%. Durable responses are seen in a subset of patients; however, many derive little clinical benefit. Biomarkers of the systemic inflammatory response predict survival in NSCLC. We evaluated their prognostic significance in patients receiving first-line pembrolizumab for advanced NSCLC. METHODS: Patients treated with first-line pembrolizumab for advanced NSCLC with programmed death-ligand 1 expression ≥50% at two regional Scottish cancer centres were identified. Pretreatment inflammatory biomarkers (white cell count, neutrophil count, neutrophil/lymphocyte ratio, platelet/lymphocyte ratio, albumin, prognostic nutritional index) were recorded. The relationship between these and progression-free survival (PFS) and overall survival (OS) were examined. RESULTS: Data were available for 219 patients. On multivariate analysis, albumin and neutrophil count were independently associated with PFS (P < 0.001, P = 0.002, respectively) and OS (both P < 0.001). A simple score combining these biomarkers was explored. The Scottish Inflammatory Prognostic Score (SIPS) assigned 1 point each for albumin <35 g/l and neutrophil count >7.5 × 109/l to give a three-tier categorical score. SIPS predicted PFS [hazard ratio 2.06, 95% confidence interval (CI) 1.68-2.52 (P < 0.001)] and OS [hazard ratio 2.33, 95% CI 1.86-2.92 (P < 0.001)]. It stratified PFS from 2.5 (SIPS2), to 8.7 (SIPS1) to 17.9 months (SIPS0) (P < 0.001) and OS from 5.1 (SIPS2), to 12.4 (SIPS1) to 28.7 months (SIPS0) (P < 0.001). The relative risk of death before 6 months was 2.96 (95% CI 1.98-4.42) in patients with SIPS2 compared with those with SIPS0-1 (P < 0.001). CONCLUSIONS: SIPS, a simple score combining albumin and neutrophil count, predicts survival in patients with NSCLC receiving first-line pembrolizumab. Unlike many proposed prognostic scores, SIPS uses only routinely collected pretreatment test results and provides a categorical score. It stratifies survival across clinically meaningful time periods that may assist clinicians and patients with treatment decisions. We advocate validation of the prognostic utility of SIPS in this and other immune checkpoint inhibitor treatment settings.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Albuminas/uso terapêutico , Biomarcadores , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Humanos , Inibidores de Checkpoint Imunológico , Inflamação/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico
13.
J Environ Manage ; 91(11): 2281-8, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20615605

RESUMO

The effects of addition of a range of organic amendments (biosolids, spent mushroom compost, green waste compost and green waste-derived biochar), at two rates, on some key chemical, physical and microbial properties of bauxite-processing residue sand were studied in a laboratory incubation study. Levels of exchangeable cations were not greatly affected by additions of amendments but extractable P was increased significantly by mushroom and green waste composts and massively (i.e. from 11.8 to 966 mg P kg(-1)) by biosolids applications. Levels of extractable NO(3)(-)-N were also greatly elevated by biosolids additions and there was a concomitant decrease in pH. Addition of all amendments decreased bulk density and increased mesoporosity, available water holding capacity and water retention at field capacity (-10 kPa), with the higher rate having a greater effect. Addition of biosolids, mushroom compost and green waste compost all increased soluble organic C, microbial biomass C, basal respiration and the activities of beta-glucosidase, L-asparaginase and alkali phosphatase enzymes. The germination index of watercress grown in the materials was greatly reduced by biosolids application and this was attributed to the combined effects of a high EC and high concentrations of extractable P and NO(3)(-). It was concluded that the increases in water storage and retention and microbial activity induced by additions of the composts is likely to improve the properties of bauxite-processing residue sand as a growth medium but that allowing time for soluble salts, originating from the organic amendments, to leach out may be an important consideration before sowing seeds.


Assuntos
Óxido de Alumínio/química , Cátions/análise , Resíduos Industriais , Eliminação de Resíduos/métodos , Dióxido de Silício/química , Microbiologia do Solo , Solo/análise , Agaricales , Respiração Celular , Enzimas/metabolismo , Germinação , Concentração de Íons de Hidrogênio , Lepidium sativum/crescimento & desenvolvimento , Fósforo/análise , Porosidade , Reciclagem/métodos , Solo/normas , Água
14.
Mol Genet Metab ; 98(1-2): 198-202, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19577495

RESUMO

Loss-of-function mutations in the flavin-containing monooxygenase 3 gene (FMO3) cause the inherited disorder trimethylaminuria (TMAuria), or fish-odour syndrome. Here we describe the identification in a family from northern Norway of a novel causative mutation of TMAuria. A female child within the family presented with a TMAuria-like phenotype. The child and her mother were found to be heterozygous for a novel mutation (R238Q) in exon 6 of FMO3. The child's father lacked this mutation, but was heterozygous for a double polymorphic variant, E158K/E308G, which was not present in the child. During a consultation with her doctor the mother mentioned an uncle whom she remembered as having a strong body odour. This discussion led to genetic counselling of the uncle and analysis of his DNA showed him to be homozygous for the R238Q mutation. Analysis of the mutant FMO3 expressed in bacteria revealed that the R238Q mutation abolished catalytic activity of the enzyme and is thus a causative mutation for TMAuria. The specificity constant (k(cat)/K(M)) of the K158/G308 variant was 43% of that of ancestral FMO3. Because the child is heterozygous for the R238Q mutation and no other mutation known to cause TMAuria was detected in her DNA she is predicted to suffer from transient childhood TMAuria, whereas her great-uncle has primary TMAuria.


Assuntos
Erros Inatos do Metabolismo/enzimologia , Erros Inatos do Metabolismo/genética , Mutação/genética , Oxigenases/genética , População Branca/genética , Alelos , Sequência de Aminoácidos , Sequência de Bases , Biocatálise , Análise Mutacional de DNA , Éxons/genética , Família , Feminino , Humanos , Cinética , Masculino , Dados de Sequência Molecular , Proteínas Mutantes/metabolismo , Noruega , Oxigenases/química , Linhagem , Estrutura Secundária de Proteína
15.
Science ; 206(4417): 470-1, 1979 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-504988

RESUMO

Phenylethylamine (PEA) is an endogenous amine that is structurally and pharmacologically related to amphetamine. Urinary PEA excretion is significantly higher in paranoid chronic schizophrenics than in nonparanoid chronic schizophrenics and normal controls. Diet, hospitalization, and medication do not account for differences in PEA concentrations. These findings offer some indication that PEA may be an endogenous amphetamine.


Assuntos
Fenetilaminas/urina , Esquizofrenia Paranoide/urina , Doença Crônica , Dieta , Hospitalização , Humanos , Esquizofrenia/urina
16.
Prev Med Rep ; 13: 41-47, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30505652

RESUMO

Invasive Meningococcal Disease is a deadly, but preventable disease, with community outbreaks occurring at rate of 9.5 per year. Serogroup C Invasive Meningococcal Disease (IMD) community outbreaks in men who have sex with men (MSM) have been reported with greater frequency in large urban areas since 2010. An effective vaccine exists that can temper and control outbreaks, and is recommended for MSM in outbreak settings; however very little is known about the perceptions, barriers and facilitators to IMD vaccine uptake among MSM. Optimizing awareness and vaccine uptake for MSM is a high priority to reduce and control IMD outbreaks. To that end, we conducted focus groups with MSM during an active IMD outbreak to inform development of a tailored intervention strategy. Participants discussed facilitators (e.g., logistics, relationships, health literacy) and barriers (e.g., fear of disclosure, medical distrust) to vaccination, as well as ideas for intervention strategies (e.g., incentives, use of internet outreach).

17.
Clin Oncol (R Coll Radiol) ; 31(10): 681-687, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31377081

RESUMO

AIMS: Stereotactic ablative body radiotherapy (SABR) is now considered the standard of care for medically inoperable stage I non-small cell lung cancer (NSCLC). The English National Cancer Registration and Analysis Service (NCRAS) collects data on all patients diagnosed with lung cancer, including information on treatment. We wanted to compare outcomes for patients with stage I NSCLC treated with radical radiotherapy with either SABR or fractionated radiotherapy. MATERIALS AND METHODS: All patients diagnosed with stage I NSCLC in 2015 and 2016 were identified from the NCRAS dataset, validated by the National Lung Cancer Audit, and their treatment data were collated. For patients who received radiotherapy, those receiving radical dose fractionations, including SABR, were identified through linkage to the national Radiotherapy Dataset. Clinical outcomes for those receiving SABR or more fractionated radical radiotherapy were compared using univariate and fully adjusted Cox proportional hazards models. RESULTS: In total, 12 384 patients with stage I NSCLC were identified during the study period; 53.5% underwent surgical resection, 24.3% received no documented treatment, 18.6% received radical radiotherapy and 3.5% received other non-curative-intent treatments. For those receiving radical radiotherapy, 69% received SABR and 31% received fractionated treatment. The hazard ratio of death for the 1587 patients who received SABR was 0.69 (95% confidence interval 0.61-0.79) compared with 717 patients who received radical fractionated radiotherapy; this benefit was seen for both stage Ia and stage Ib disease. The median overall survival was also longer for SABR versus radical radiotherapy (715 days versus 648 days). Exploratory travel time analysis shows that compared with stage I NSCLC patients receiving SABR, those receiving fractionated radiotherapy and those receiving no active treatment would have to travel longer and further to reach their nearest radiotherapy SABR centre. CONCLUSION: This study adds to the data that SABR has a survival benefit when compared with fractionated radical radiotherapy. Although the use of SABR increased in England over this study period, it has still not reached levels of use seen in other countries. This study also highlights that one quarter of stage I NSCLC patients overall received no active treatment.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/mortalidade , Neoplasias Pulmonares/mortalidade , Radiocirurgia/mortalidade , Radioterapia/mortalidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Fracionamento da Dose de Radiação , Inglaterra , Feminino , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Taxa de Sobrevida , Resultado do Tratamento , Adulto Jovem
19.
Environ Pollut ; 247: 438-446, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30690240

RESUMO

Low nitrogen (N) content and retention in bauxite-processing residue sand (BRS) disposal areas pose a great challenge to the establishment of sustainable vegetation cover in this highly alkaline environment. The budget and fate of applied N in BRS and its potential environmental impacts are largely unknown. We investigated the effect of combined application of biochars [aged acidic (AC) vs alkaline pine (PC)] and di-ammonium phosphate (DAP) fertiliser on ammonia (NH3) volatilisation, nitrous oxide (N2O) emission and N retention in a 116-day glasshouse study. The application of AC to BRS decreased pH (≈0.5 units) in BRS, while PC biochar increased pH (≈0.3 units). The application of AC reduced NH3 volatilisation by ca. 80%, while PC by ca. 25%. On the other hand, the AC treatment increased N2O emission by 5 folds. However, the N loss via N2O emission in the AC treatment only accounted for ca. 0.4% of applied N. The reduction in BRS pH and increased retention of mineral N due to the presence of oxygen-containing (phenolic and carboxylic) functional groups in AC may be responsible for reduced NH3 volatilisation and increased N2O emission. This study has highlighted the potential of biochar (particularly aged biochar) in improving N retention and minimising environmental impacts in highly alkaline environments.


Assuntos
Óxido de Alumínio/química , Carvão Vegetal/química , Modelos Químicos , Nitrogênio/análise , Amônia/análise , Fertilizantes , Óxido Nitroso/análise , Fosfatos , Dióxido de Silício/química , Solo/química , Volatilização
20.
Phys Med Biol ; 64(16): 165012, 2019 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-31117063

RESUMO

This paper studies the sensitivity of a range of image texture parameters used in radiomics to: (i) the number of intensity levels, (ii) the method of quantisation to select the intensity levels and (iii) the use of an intensity threshold. 43 commonly used texture features were studied for the gross target volume outlined on the CT component of PET/CT scans of 50 patients with non-small cell lung carcinoma (NSCLC). All cases were quantised for all values between 4 and 128 intensity levels using four commonly used quantisation methods. All results were analysed with and without a threshold range of -200 HU to 300 HU. Cases were ranked for each texture feature and for all quantisation methods with the Spearman's rank correlation coefficient determined to evaluate stability. Results showed large fluctuations in ranking, particularly for low numbers of levels, differences between quantisation methods and with the use of a threshold, with values Spearman's Rank Correlation for many parameters below 0.2. Our results demonstrated the sensitivity of radiomics features to the parameters used during analysis and highlight the risk of low reproducibility comparing studies with slightly different parameters. In terms of the lung cancer CT datasets, this study supports the use of 128 intensity levels, the same uniform quantiser applied to all scans and thresholding of the data. It also supports several of the features recommended in the literature for such studies such as skewness and kurtosis. A recommended framework is presented for curation of the data analysis process to ensure stability of results.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Processamento de Imagem Assistida por Computador , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/metabolismo , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Carcinoma Pulmonar de Células não Pequenas/patologia , Humanos , Neoplasias Pulmonares/patologia , Reprodutibilidade dos Testes
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