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In this study, patients with acute respiratory distress syndrome who were not receiving statins were assigned to receive simvastatin or placebo. At 28 days, there were no significant between-group differences in survival or in the number of ventilator-free days. The acute respiratory distress syndrome (ARDS) is a common, devastating clinical syndrome characterized by life-threatening respiratory failure requiring mechanical ventilation and by multiple organ failure. In ARDS there is an uncontrolled inflammatory response that results in alveolar damage, with the exudation of protein-rich pulmonary-edema fluid in the alveolar space that results in respiratory failure. 1 The inhibition of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase with statins has been shown to modify a number of the underlying mechanisms implicated in the development of ARDS. 2 Statins decrease inflammation and histologic evidence of lung injury in murine models of ARDS. 3 Simvastatin reduced pulmonary and systemic . . .

Landslide mapping (LM) has recently become an important research topic in remote sensing and geohazards. The area near the Three Gorges Reservoir (TGR) along the Yangtze River in China is one of the most landslide-prone regions in the world, and the area has suffered widespread and significant landslide events in recent years. In our study, an object-oriented landslide mapping (OOLM) framework was proposed for reliable and accurate LM from ‘ZY-3’ high spatial resolution (HSR) satellite images. The framework was based on random forests (RF) and mathematical morphology (MM). RF was first applied as an object feature information reduction tool to identify the significant features for describing landslides, and it was then combined with MM to map the landslides. Three object-feature domains were extracted from the ‘ZY-3’ HSR data: layer information, texture, and geometric features. A total group of 124 features and 24 landslides were used as inputs to determine the landslide boundaries and evaluate the landslide classification accuracy. The results showed that: (1) the feature selection (FS) method had a positive influence on effective landslide mapping; (2) by dividing the data into two sets, training sets which consisted of 20% of the landslide objects (OLS) and non-landslide objects (ONLS), and test sets which consisted of the remaining 80% of the OLS and ONLS, the selected feature subsets were combined for training to obtain an overall classification accuracy of 93.3% ± 0.12% of the test sets; (3) four MM operations based on closing and opening were used to improve the performance of the RF classification. Seven accuracy evaluation indices were used to compare the accuracies of these landslide mapping methods. Finally, the landslide inventory maps were obtained. Based on its efficiency and accuracy, the proposed approach can be employed for rapid response to natural hazards in the Three Gorges area.

This paper provides a study of the changes in land use in urban environments in two cities, Wuhan, China and western Sydney in Australia. Since mixed pixels are a characteristic of medium resolution images such as Landsat, when used for the classification of urban areas, due to changes in urban ground cover within a pixel, Multiple Endmember Spectral Mixture Analysis (MESMA) together with Super-Resolution Mapping (SRM) are employed to derive class fractions to generate classification maps at a higher spatial resolution using an Artificial Neural Network (ANN) predicted Wavelet method. Landsat images over the two cities for a 30-year period, are classified in terms of vegetation, buildings, soil and water. The classifications are then processed using Indifrag software to assess the levels of fragmentation caused by changes in the areas of buildings, vegetation, water and soil over the 30 years. The extents of fragmentation of vegetation, buildings, water and soil for the two cities are compared, while the percentages of vegetation are compared with recommended percentages of green space for urban areas for the benefit of health and well-being of inhabitants. Changes in Ecosystem Service Values (ESVs) resulting from the urbanization have been assessed for Wuhan and Sydney. The UN Sustainable Development Goals (SDG) for urban areas are being assessed by researchers to better understand how to achieve the sustainability of cities.

Synthetic aperture radar (SAR) imaging systems derive microwave data, from space or airborne (piloted and remote piloted), that provide opportunities for the interpretation of many characteristics of the terrain surface. The increasing number of satellites equipped with SAR data acquisition systems that are being launched with a range of wavelengths, polarizations, and operating characteristics are enabling a better understanding of the earth’s environment, for such activities as vegetation analysis, forest inventories, land subsidence, and urban analysis. In addition, airborne systems for remote piloted systems and ground-based systems are available. This Special Issue presents six quality scientific papers on typical applications of SAR technologies. They include methods for the determination of above ground biomass (AGB), crop mapping using data from an advanced X-band system developed in Japan, analysis of natural and human-induced slow-rate ground deformations in the region of Campania, in Italy, the location of landslides caused by natural phenomena based on SAR images derived from the Japanese high-resolution Advanced Land Observing Satellite-2 (ALOS-2), and monitoring the size of refugee camps and their environmental impacts caused by the displacement of people from Myanmar to the Cox’s Bazar District, around Kutupalong, in Bangladesh. The paper concludes with some comments on the future directions of developments in SAR systems.

ObjectiveTo investigate the effectiveness of a 6-week exercise programme in patients discharged home following critical illness compared with standard care.DesignMulticentre prospective phase II randomised controlled trial, with blinded outcome assessment after hospital discharge, following the 6-week intervention and at 6 months.Participants60 patients (30 per group) aged ≥18 years, mechanically ventilated >96 hours, and not in other rehabilitation, that is, cardiac or pulmonary rehabilitation programmes. Participants in the intervention group completed an individually tailored (personalised) exercise programme.Outcome measuresPrimary outcome measure was SF-36 physical functioning following the intervention. Secondary outcomes included a range of performance-based and patient-reported measures.ResultsImprovements in the primary outcome did not differ significantly between groups (mean difference (95% CI) 3.0 (−2.2 to 8.2), p=0.26). The intervention group showed significant improvement compared with the control group (mean difference (95% CI)) in SF-36 role physical (6.6 (0.73 to 12.5), p=0.03); incremental shuttle walk test (83.1 m (8.3 to 157.9), p=0.03); functional limitations profile (−4.8 (−8.7 to −0.9), p=0.02); self-efficacy to exercise (2.2 (0.8 to 3.7), p=0.01) and readiness to exercise (1.3 (0.8 to 1.9), p<0.001). These improvements were not sustained at 6 months except readiness to exercise. Improvements in all other secondary outcome measures were not significant.ConclusionsThere was no statistically significant difference in the primary outcome measure of self-reported physical function following this 6-week exercise programme. Secondary outcome results will help inform future studies.Trial registration numberNCT01463579. (results), https://clinicaltrials.gov/

If one considers the normal stable sleeping CO2 to be 2-4 mm Hg higher than the waking level, we calculated that approximately 80% of patients have mean CO2 below this level at sleep resumption, suggesting that many arousals in these participants do result in relative hypocapnia (63). [...]if sedatives reduce the number of events that end in arousal and thus reduce the hyperventilation and hypocapnia associated with airway opening, they may improve OSA in many patients, although this assumes that sedatives do not alter the magnitude of the ventilatory response itself. [...]several groups have attempted to identify surrogate markers of physiological variables on the clinical polysomnogram that could be used to identify patients who are likely to be successfully treated with a given individualized treatment (67-69). There may also be a significant incentive for pharmaceutical companies to develop suitable sedating agents to treat OSA if a significant proportion of patients benefit from treatment and can be easily identified. [...]there may well be suitable sedatives available for future clinical trials and longterm use in carefully selected patients with OSA. [...]on the basis of current available evidence of minimal worsening of OSA with sedatives, at least at the group level, some clinicians may be comfortable trialing sedatives in patients with mild OSA/minimal desaturation and comorbid insomnia/sleep disturbance.

Abstract This study investigated whether a change in posture affected the activity of the upper-airway dilator muscle genioglossus in participants with and without obstructive sleep apnea (OSA). During wakefulness, a monopolar needle electrode was used to record single motor unit activity in genioglossus in supine and upright positions to alter the gravitational load that causes narrowing of the upper airway. Activity from 472 motor units was recorded during quiet breathing in 17 males, nine of whom had OSA. The mean number of motor units for each participant was 11.8 (SD 3.4) in the upright and 16.0 (SD 4.2) in the supine posture. For respiratory-modulated motor units, there were no significant differences in discharge frequencies between healthy controls and participants with OSA. Within each breath, genioglossus activity increased through the recruitment of phasic motor units and an increase in firing rate, with an overall increase of ~6 Hz (50%) across both postures and participant groups. However, the supine posture did not lead to compensatory increases in the peak discharge frequencies of inspiratory and expiratory motor units, despite the increase in gravitational load on the upper airway. Posture also had no significant effect on the discharge frequency of motor units that showed no respiratory modulation during quiet breathing. We postulate that, in wakefulness, any increase in genioglossus activity to compensate for the gravitational effects on the upper airway is achieved primarily through the recruitment of additional motor units in both healthy controls and participants with OSA.

A total of 20-30% of respiratory events in obstructive sleep apnea are terminated without clear arousal. Arousals are thought to predispose to further events by promoting hyperventilation, hypocapnia, and upper-airway dilator muscle hypotonia. Therefore, events terminated without arousal may promote stable breathing. To compare physiologic changes at respiratory event termination with American Sleep Disorders Association (ASDA) Arousal to No Arousal, and determine whether secondary respiratory events are less common and have higher dilator muscle activity after No Arousal compared with ASDA Arousal. Patients with obstructive sleep apnea wore sleep staging, genioglossus (EMG(GG)), and tensor palatini (EMG(TP)) electrodes plus a nasal mask and pneumotachograph. During stable sleep, continuous positive airway pressure (CPAP) was lowered for 3-minute periods to induce respiratory events. Physiologic variables were compared between events terminated with (1) ASDA Arousal, (2) No Arousal, or (3) sudden CPAP increase (CPAPinc, control). Sixteen subjects had adequate data. EMG(GG), EMG(TP), and heart rate increased after ASDA Arousal (340 ± 57%, 215 ± 28%, and 110.7 ± 2.3%) and No Arousal (185 ± 32%, 167 ± 15%, and 108.5 ± 1.6%) but not CPAPinc (90 ± 10%, 94 ± 11%, and 102.1 ± 1%). Ventilation increased more after ASDA Arousal than No Arousal and CPAPinc, but not after accounting for the severity of respiratory event. Fewer No Arousals were followed by secondary events than ASDA Arousals. However, low dilator muscle activity did not occur after ASDA Arousal or No Arousal (EMG(GG) rose from 75 ± 5 to 125 ± 7%) and secondary events were less severe than initial events (ventilation rose 4 ± 0.4 to 5.5 ± 0.51 L/min). Respiratory events that were terminated with ASDA Arousal were more severely flow-limited, had enhanced hyperventilation after event termination, and were more often followed by secondary events than No arousal. However, secondary events were not associated with low dilator muscle activity and airflow was improved after both No Arousal and ASDA Arousal.

ObjectivesObtaining informed consent from patients in intensive care units (ICUs) prior to enrolment in a study is practically and ethically complex. Decisions about the participation of critically ill patients in research often involve substitute decision makers (SDMs), such as a patient’s relatives or doctors. We explored the perspectives of different stakeholder groups towards these consent procedures.Design and methodsMixed-methods study comprising surveys completed by ICU patients, their relatives and healthcare practitioners in 14 English ICUs, followed by qualitative interviews with a subset of survey participants. Empirical bioethics informed the analysis and synthesis of the data. Survey data were analysed using descriptive statistics of Likert responses, and analysis of interview data was informed by thematic reflective approaches.ResultsAnalysis included 1409 survey responses (ICU patients n=333, relatives n=488, healthcare practitioners n=588) and 60 interviews (ICU patients n=13, relatives n=30, healthcare practitioners n=17). Most agreed with relatives acting as SDMs based on the perception that relatives often know the patient well enough to reflect their views. While the practice of doctors serving as SDMs was supported by most survey respondents, a quarter (25%) disagreed. Views were more positive at interview and shifted markedly depending on particularities of the study. Participants also wanted reassurance that patient care was prioritised over research recruitment. Findings lend support for adaptations to consent procedures, including collaborative decision-making to correct misunderstandings of the implications of research for that patient. This empirical evidence is used to develop good practice guidance that is to be published separately.ConclusionsParticipants largely supported existing consent procedures, but their perspectives on these consent procedures depended on their perceptions of what the research involved and the safeguards in place. Findings point to the importance of explaining clearly what safeguards are in place to protect the patient.

The genioglossus is a major upper airway dilator muscle thought to be important in obstructive sleep apnea pathogenesis. Aging is a risk factor for obstructive sleep apnea although the mechanisms are unclear and the effects of aging on motor unit remodeled in the genioglossus remains unknown. To assess possible changes associated with aging we compared quantitative parameters related to motor unit potential morphology derived from EMG signals in a sample of older (n = 11; >55 years) versus younger (n = 29; <55 years) adults. All data were recorded during quiet breathing with the subjects awake. Diagnostic sleep studies (Apnea Hypopnea Index) confirmed the presence or absence of obstructive sleep apnea. Genioglossus EMG signals were analyzed offline by automated software (DQEMG), which estimated a MUP template from each extracted motor unit potential train (MUPT) for both the selective concentric needle and concentric needle macro (CNMACRO) recorded EMG signals. 2074 MUPTs from 40 subjects (mean±95% CI; older AHI 19.6±9.9 events/hr versus younger AHI 30.1±6.1 events/hr) were extracted. MUPs detected in older adults were 32% longer in duration (14.7±0.5 ms versus 11.1±0.2 ms; P  =  0.05), with similar amplitudes (395.2±25.1 µV versus 394.6±13.7 µV). Amplitudes of CNMACRO MUPs detected in older adults were larger by 22% (62.7±6.5 µV versus 51.3±3.0 µV; P<0.05), with areas 24% larger (160.6±18.6 µV.ms versus 130.0±7.4 µV.ms; P<0.05) than those detected in younger adults. These results confirm that remodeled motor units are present in the genioglossus muscle of individuals above 55 years, which may have implications for OSA pathogenesis and aging related upper airway collapsibility.