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1.
Sci Rep ; 14(1): 14360, 2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38906899

ABSTRACT

Identifying lithologies in meteorite impact craters is an important task to unlock processes that have shaped the evolution of planetary bodies. Traditional methods for lithology identification rely on time-consuming manual analysis, which is costly and limits the efficiency of rapid decision-making. This paper utilizes different machine learning algorithms namely Random Forest, Decision Tree, K Nearest Neighbors, and Logistic Regression with Grid Search to classify rock lithologies using data from the Bosumtwi impact crater in Ghana. A repeated stratified k-fold cross-validation method is applied to Grid Search to select the best combination of hyperparameters. The findings demonstrate that the Random Forest algorithm achieves the most promising results in classifying lithologies in the meteorite impact crater with an accuracy score of 86.89%, a recall score of 84.88%, a precision score of 87.21%, and an F1 score of 85.48%. The findings also suggest that more high-quality data has the potential to further increase the accuracy scores of the machine learning algorithm. In conclusion, this study demonstrates the significant potential of machine learning techniques to revolutionize lithology identification in meteorite impact craters, thus paving the way for their influential role in future space exploration endeavors.

2.
Heliyon ; 10(10): e31536, 2024 May 30.
Article in English | MEDLINE | ID: mdl-38803987

ABSTRACT

Seismic activities pose significant challenges to societies globally. Therefore, it is crucial to understand their occurrence, patterns, and impacts. By studying seismic activities, including earthquakes, researchers can investigate their occurrence, distribution, and characteristics which can provide effective management and risk reduction strategies. The southern part of Ghana is prone to earthquakes and this study aims to shed more light into the nature of seismic events in the area and country at large. A systematic review was conducted using the PRISMA technique across three electronic databases (SCOPUS, Dimensions and Google Scholar) to identify relevant studies published between 2000 and 2023. Extraction of data and quality assessment were performed in order to ensure reliability and validity of included studies. Results identified only 17 papers from published records to meet the inclusion criteria. Despite the grave threat earthquakes pose to vital infrastructure and human life in Ghana, research in this area remains remarkably deficient. Our findings underscore the urgent need for further study given the catastrophic potential of seismic disasters in the region. Moreover, upon scrutinizing the methodologies deployed in extant literature concerning seismic activity in Ghana, a recurring constraint that emerged was the scarce availability of data. In essence, this study offers an indispensable panorama of earthquake research in Ghana, bridging the existing knowledge chasm on seismic phenomena in the region. The insights gleaned from this review promise to fortify our comprehension of Ghana's seismic activities, thereby bolstering the country's capabilities for more effective preparedness and response strategies.

3.
J Environ Sci (China) ; 127: 295-307, 2023 May.
Article in English | MEDLINE | ID: mdl-36522061

ABSTRACT

Straw pellets are widely promoted and expected to be a cleaner alternative fuel to unprocessed crop residues and raw coal in rural China. However, the effectiveness of these dissemination programs is not well evaluated. In this field study, emission characteristics of burning straw pellets, raw coal, and unprocessed corn cobs in heating stoves were investigated in a pilot village in Northeast China. Emission measurements covering the whole combustion cycle (ignition, flaming, and smoldering phases) shows the promotion of improved heating stoves and straw pellets could reduce pollutant emissions (e.g., SO2 and CO), but increase NOX and PM2.5 emissions compared to the initial stove-fuel use pattern in the studied area. There is a significant variance in emission characteristics between different combustion phases. The normalized emission concentrations of the different stove-fuel combinations were higher than the limits in the Chinese national standard for heating stoves, indicating that the standard is not met for real-world emissions. Coal consumption was lower than official data. Household surveys were conducted to identify the barriers to fuel and stove access associated with existing promotion strategies, management, and policies. The pilot program was of the typical "subsidy-and-policy-dependence" pattern and was unlikely to be implemented on a large scale. Technological innovation, operational optimization, and proper policies considering the local socioeconomic factors are needed to sustain the promotion of biomass straw pellets and stoves.


Subject(s)
Air Pollutants , Heating , Particulate Matter/analysis , Air Pollutants/analysis , Coal/analysis , China , Cooking
4.
Sci Total Environ ; 823: 153718, 2022 Jun 01.
Article in English | MEDLINE | ID: mdl-35149075

ABSTRACT

Household heating stoves are commonly used for heating in rural China during winter and are responsible for a large portion of the particulate matter in the atmosphere. Pollutant emissions from household stoves are influenced by user behaviors in actual use, in addition to purely technological reasons (i.e., type and age of appliance) and installation conditions (i.e., the natural draft of chimney system). The variability in user behavior is one of the reasons for uncertainty in household emission inventories. In this study, household stove user behaviors, including ignition frequency, heating with or without cooking, smoldering duration, and fuel-adding times, were investigated through face-to-face surveys in Shanxi province, north China. The survey of user behaviors showed that the majority of the RHS users (81.3%) and approximately half of the WHS users (49.4%) used their stoves for both cooking and heating, whereas the remaining users used their stoves just for heating. Approximately 80% of surveyed households (97.4% for water heating stove and 68.7% for radiant heating stove) kept the stoves smoldering at night, whereas the remaining users ignited their stoves every day. The highest frequency of smoldering duration and highest frequency of fuel-adding operation were 8-9 h and 4-7 times, respectively. Principal component analysis showed that stove type, permanent population, and annual income are the potential influencing factors of user behavior. The smoldering duration was positively related to indoor air pollutant concentrations and fuel-adding times had a significant impact on outdoor PM2.5 emission factors. The results from this research will be beneficial for understanding the cause of fluctuation in emissions and designing heating appliances for real-life operations.


Subject(s)
Air Pollutants , Air Pollution, Indoor , Environmental Pollutants , Household Articles , Air Pollutants/analysis , Air Pollution, Indoor/analysis , China , Cooking , Environmental Pollutants/analysis , Heating , Humans , Particulate Matter/analysis , Rural Population
5.
Environ Pollut ; 280: 116955, 2021 Jul 01.
Article in English | MEDLINE | ID: mdl-33813351

ABSTRACT

The use of coal in Chinese households for winter heating emits harmful pollutants that severely affect indoor air quality and climate. Therefore, China has made efforts to transition into clean heating using improved heating stoves and biomass pellets. Although the economic and policy implications of such demonstration projects have been extensively investigated, little has been done to understand the real-world performance and adoption trends of such stoves. This study measured in-use emissions from nine different pellet stoves used for heating among 52 rural households in Yangxin, Shandong Province. The temperature of the stove chimney of 21 households was monitored and 56 households were surveyed to explore the stove use trend. The particulate and gaseous emission concentrations for most of the stoves exceeded the limits specified in the Chinese national standard. The measured fuel energy-based emission factors (mean ± standard deviation) for CO2, CO, NOx, and PM2.5 were 103 ± 3, 1.41 ± 1.19, 0.336 ± 0.237, and 0.146 ± 0.108 g/MJ, respectively. Between January to February, the average daily heating duration was 8.71 h, and the sustained use of heating stoves was seen among over 85% of the households. On average, the households used their heating stoves for 3.28 months and the estimated annual pellets consumption for a household was 2.7 tons. Besides inherent variabilities associated with user habits, the stove's design-related shortcomings and low-grade pellets hindered the performance and effectiveness of pellet stoves. This study provides insights into opportunities and challenges for the promotion of cleaner fuels and heating technologies. Furthermore, it will provide information on emissions from rural residential sources to build the emission inventory and inform policymaking for successful stove promotion programs.


Subject(s)
Air Pollutants , Air Pollution, Indoor , Air Pollutants/analysis , Air Pollution, Indoor/analysis , China , Cooking , Heating , Humans , Particulate Matter/analysis
6.
Sci Rep ; 10(1): 13357, 2020 Aug 07.
Article in English | MEDLINE | ID: mdl-32770135

ABSTRACT

Due to the lack of petroleum resources, stratigraphic reservoirs have become an important source of future discoveries. We describe a methodology for predicting reservoir sands from complex reservoir seismic data. Data analysis involves a bio-integrated framework called multi-modal machine learning fusion (MMMLF) based on neural networks. First, acoustic-related seismic attributes from post-stack seismic data were used to characterize the reservoirs. They enhanced the understanding of the structure and spatial distribution of petrophysical properties of lithostratigraphic reservoirs. The attributes were then classified as varied modal inputs into a central fusion engine for prediction. We applied the method to a dataset from Northeast China. Using seismic attributes and rock physics relationships as input data, MMMLF was performed to predict the spatial distribution of lithology in the Upper Guantao substrata. Despite the large scattering in the acoustic-related data properties, the proposed MMMLF methodology predicted the distribution of lithological properties through the gamma ray logs. Moreover, complex stratigraphic traps such as braided fluvial sandstones in the fluvio-deltaic deposits were delineated. These findings can have significant implications for future exploration and production in Northeast China and similar petroleum provinces around the world.

7.
Chem Cent J ; 12(1): 81, 2018 Jul 11.
Article in English | MEDLINE | ID: mdl-29995251

ABSTRACT

The removal of malachite green (MG) from aqueous solution using teak leaf litter powder (TLLP) was investigated. The process was influenced by initial concentration, pH and temperature of dye solution as well as TLLP dosage. Optimum removal of MG per gram of TLLP occurred at 2 g/L and at pH 6-8. Dubinin-Radushkevich and Freundlich isotherm models fit the batch adsorption data better than Langmuir isotherm. The monolayer capacity of TLLP was 333.33 mg/g at 293-313 K. The mean free energy of 7.07 kJ/mol implied physical adsorption. The pseudo-second order model fit the kinetic data better than the pseudo-first order model. Both intraparticle diffusion and film diffusion mechanisms jointly influenced the adsorption process but the latter was the rate-controlling step. Thermodynamic data indicated that the process was endothermic, spontaneous and feasible. Therefore, TLLP could be an important low-cost adsorbent for removal of MG from aqueous solution.

8.
Sci Rep ; 7(1): 12198, 2017 09 22.
Article in English | MEDLINE | ID: mdl-28939814

ABSTRACT

Low-cost teak leaf litter powder (TLLP) was prepared as possible substitute for activated carbon. The feasibility of using the adsorbent to remove eosin yellow (EY) dye from aqueous solution was investigated through equilibrium adsorption, kinetic and thermodynamic studies. The removal of dye from aqueous solution was feasible but influenced by temperature, pH, adsorbent dosage and contact time. Variation in the initial concentration of dye did not influence the equilibrium contact time. Optimum adsorption of dye occurred at low adsorbent dosages, alkaline pH and high temperatures. Langmuir isotherm model best fit the equilibrium adsorption data and the maximum monolayer capacity of the adsorbent was 31.64 mg g-1 at 303 K. The adsorption process was best described by pseudo-second order kinetic model at 303 K. Boundary layer diffusion played a key role in the adsorption process. The mechanism of uptake of EY by TLLP was controlled by both liquid film diffusion and intraparticle diffusion. The values of mean adsorption free energy, E (7.91 kJ mol-1), and standard enthalpy, ΔH° (+13.34 kJ mol-1), suggest physical adsorption. The adsorption process was endothermic and spontaneous. Teak leaf litter powder is a promising low-cost adsorbent for treating wastewaters containing eosin yellow.

10.
Popul Environ ; 37(3): 362-390, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26997690

ABSTRACT

We examined patterns of shifting cropland cultivation in the US Great Plains from the dust bowl to the beginning of the 21st century, by comparing land-cover data from 400 sample sites across the region from the 1930s, 1950s, 1970s and, 1990s and 2000s. We argue that understanding the use of marginal land for cultivation in the Great Plains since the Great Depression requires understanding the interacting dynamics of demography, technology, and policy. The small area land-cover data are nested within 50 target counties across the region. We draw on these dynamics, and their interactions with a range of policy programs aimed at reducing environmental impacts of agriculture, to tell the story of how and when marginal lands have been brought into use. In a multi-level panel design, macro- and micro-level covariates were used to predict levels of encroachment on marginal soils. We conclude that land retirement programs (like the Conservation Reserve Program) have had a generally stabilizing effect on the micro-level patterns of land use in recent decades, but that increased levels of encroachment on marginal soils and native grassland remain a problem in areas with higher or increasing population densities.

11.
J Intellect Disabil Res ; 60(2): 149-55, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26018613

ABSTRACT

BACKGROUND: We report striking and unanticipated improvements in maladaptive behaviours in Prader-Willi syndrome (PWS) during a trial of vagus nerve stimulation (VNS) initially designed to investigate effects on the overeating behaviour. PWS is a genetically determined neurodevelopmental disorder associated with mild-moderate intellectual disability (ID) and social and behavioural difficulties, alongside a characteristic and severe hyperphagia. METHODS: Three individuals with PWS underwent surgery to implant the VNS device. VNS was switched on 3 months post-implantation, with an initial 0.25 mA output current incrementally increased to a maximum of 1.5 mA as tolerated by each individual. Participants were followed up monthly. RESULTS: Vagal nerve stimulation in these individuals with PWS, within the stimulation parameters used here, was safe and acceptable. However, changes in eating behaviour were equivocal. Intriguingly, unanticipated, although consistent, beneficial effects were reported by two participants and their carers in maladaptive behaviour, temperament and social functioning. These improvements and associated effects on food-seeking behaviour, but not weight, indicate that VNS may have potential as a novel treatment for such behaviours. CONCLUSIONS: We propose that these changes are mediated through afferent and efferent vagal projections and their effects on specific neural networks and functioning of the autonomic nervous system and provide new insights into the mechanisms that underpin what are serious and common problems affecting people with IDs more generally.


Subject(s)
Aggression/physiology , Feeding and Eating Disorders/therapy , Prader-Willi Syndrome/therapy , Social Behavior Disorders/therapy , Vagus Nerve Stimulation/methods , Adult , Body Composition , Body Weight , Feeding and Eating Disorders/etiology , Female , Humans , Male , Prader-Willi Syndrome/complications , Social Behavior Disorders/etiology , Treatment Outcome , Vagus Nerve Stimulation/adverse effects , Young Adult
12.
Thorax ; 64(6): 490-5, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19213770

ABSTRACT

BACKGROUND: Hospitalisation due to respiratory syncytial virus (RSV) infection in the first 2 years after birth has been associated with increased healthcare utilisation and associated costs up to 5 years of age in children born prematurely at less than 32 weeks of gestation who developed bronchopulmonary dysplasia (BPD). A study was undertaken to determine whether hospitalisation due to RSV infection in the first 2 years was associated with increased morbidity and lung function abnormalities in such children at school age, and if any effects were influenced by age. METHODS: Healthcare utilisation and cost of care in years 5-7 were reviewed in 147 children and changes in healthcare utilisation between 0 and 8 years were assessed also using results from two previous studies. At age 8-10 years, 77 children had their lung function assessed and bronchial hyper-responsiveness determined. RESULTS: Children hospitalised with RSV infection (n = 25) in the first 2 years had a greater cost of care related to outpatient attendance than those with a non-respiratory or no admission (n = 72) when aged 5-7 years (p = 0.008). At 8-10 years of age, children hospitalised with RSV infection (n = 14) had lower forced expiratory volume in 0.75 s (FEV(0.75)) (p = 0.015), FEV(0.75)/forced vital capacity (p = 0.027) and flows at 50% (p = 0.034) and 75% (p = 0.006) of vital capacity than children hospitalised for non-RSV causes (n = 63). Healthcare utilisation decreased with increasing age regardless of RSV hospitalisation status. CONCLUSIONS: In prematurely born children who had BPD, hospitalisation due to RSV infection in the first 2 years is associated with reduced airway calibre at school age.


Subject(s)
Bronchopulmonary Dysplasia/virology , Infant, Premature, Diseases/physiopathology , Respiratory Syncytial Virus Infections/complications , Age Factors , Bronchopulmonary Dysplasia/economics , Bronchopulmonary Dysplasia/physiopathology , Delivery of Health Care/statistics & numerical data , England , Health Care Costs/statistics & numerical data , Hospitalization , Humans , Infant, Newborn , Infant, Premature , Infant, Premature, Diseases/economics , Lung/physiopathology , Prognosis , Quality of Life , Respiratory Syncytial Virus Infections/economics , Respiratory Syncytial Virus Infections/physiopathology
13.
J Perinatol ; 28(10): 665-74, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18784730

ABSTRACT

OBJECTIVE: Necrotizing enterocolitis (NEC) remains a major cause of neonatal morbidity and mortality. Some infants recover uneventfully with medical therapy whereas others develop severe disease (that is, NEC requiring surgery or resulting in death). Repeated attempts to identify clinical parameters that would reliably identify infants with NEC most likely to progress to severe disease have been unsuccessful. We hypothesized that comprehensive prospective data collection at multiple centers would allow us to develop a model which would identify those babies at risk for progressive NEC. STUDY DESIGN: This prospective, observational study was conducted at six university children's hospitals. Study subjects were neonates with suspected or confirmed NEC. Comprehensive maternal and newborn histories were collected at the time of enrollment, and newborn clinical data were collected prospectively, thereafter. Multivariate logistic regression analysis was used to develop a predictive model of risk factors for progression. RESULT: Of 455 neonates analyzed, 192 (42%) progressed to severe disease, and 263 (58%) advanced to full feedings without operation. The vast majority of the variables studied proved not to be associated with progression to severe disease. A total of 12 independent predictors for progression were identified, including only 3 not previously described: having a teenaged mother (odds ratio, OR, 3.14; 95% confidence interval, CI, 1.45 to 6.96), receiving cardiac compressions and/or resuscitative drugs at birth (OR, 2.51; 95% CI, 1.17 to 5.48), and having never received enteral feeding before diagnosis (OR, 2.41; 95% CI, 1.08 to 5.52). CONCLUSION: Our hypothesis proved false. Rigorous prospective data collection of a sufficient number of patients did not allow us to create a model sufficiently predictive of progressive NEC to be clinically useful. It appears increasingly likely that further analysis of clinical parameters alone will not lead to a significant improvement in our understanding of NEC. We believe that future studies must focus on advanced biologic parameters in conjunction with clinical findings.


Subject(s)
Enterocolitis, Necrotizing/etiology , Infant, Premature, Diseases/etiology , Enteral Nutrition , Enterocolitis, Necrotizing/diagnosis , Enterocolitis, Necrotizing/therapy , Female , Humans , Infant, Low Birth Weight , Infant, Newborn , Infant, Premature , Infant, Premature, Diseases/diagnosis , Infant, Premature, Diseases/therapy , Logistic Models , Male , Predictive Value of Tests , Prospective Studies , Risk Factors , Severity of Illness Index , Treatment Outcome
14.
Acta Paediatr ; 96(9): 1308-10, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17666101

ABSTRACT

AIMS: To create a reference range of peak expiratory flow (PEF) results of Afro-Caribbean children and determine whether interpretation of PEF results in children with sickle cell anaemia (SCA) differed according to whether comparison was made of results obtained from children of similar age or height. METHODS: A prospective observational study was carried out in two specialist sickle cell disease clinics. Seventy-eight nonasthmatic African and Caribbean (AC) controls (age range 2.6-17.8 years), and 99 nonasthmatic SCA children (age range 3.4-17.3 years) were recruited. PEF was measured using a dry rolling sealed spirometer before and after bronchodilator therapy. RESULTS: PEF results in the AC controls correlated with height (r = 0.88, p< 0.0001). Comparison of similarly aged children demonstrated that pre- (p = 0.02) and post- (p = 0.04) bronchodilator PEF results were lower in the SCA children, but comparison of children of similar height revealed no statistically significant differences in PEF results between children with SCA and controls. The SCA children tended to be shorter than the controls. CONCLUSION: The results suggest PEF measurements are not a useful method of monitoring the respiratory status of children with sickle cell disease.


Subject(s)
Anemia, Sickle Cell/ethnology , Anemia, Sickle Cell/physiopathology , Peak Expiratory Flow Rate/drug effects , Adolescent , Bronchodilator Agents/administration & dosage , Bronchodilator Agents/pharmacology , Caribbean Region , Child , Child, Preschool , Female , Humans , Male , Prospective Studies , Respiration
15.
Eur Respir J ; 28(4): 832-8, 2006 Oct.
Article in English | MEDLINE | ID: mdl-16737989

ABSTRACT

The aim of this study was to determine whether patients with sickle cell disease (SCD) in steady state had pulmonary abnormalities seen on high-resolution computed tomography (HRCT) and whether any abnormalities correlated with contemporaneously diagnosed lung function abnormalities. A subsidiary question was whether the results of a noninvasive measure of haemolysis (end-tidal carbon monoxide (ETCO) levels) correlated with pulmonary function abnormalities. Thirty three patients with SCD, median (range) age 36 yrs (17-67 yrs) were examined. The degree of lobar volume loss and ground-glass opacification and prominence of central vessels on HRCT were quantitatively assessed. Pulmonary function was assessed by measurements of lung volumes, spirometry, gas transfer and oxygen saturation. ETCO levels were measured using an end-tidal CO monitor. Forced expiratory volume in one second (FEV1), forced vital capacity and total lung capacity significantly correlated with HRCT findings, particularly lobar volume loss. ETCO levels significantly negatively correlated with FEV1, vital capacity measured using a plethysmograph, specific airway conductance and arterial oxygen saturation measured by pulse oxymetry. In conclusion, the present results suggest that high-resolution computed tomography noninvasive assessment of haemolysis might be useful to identify sickle cell disease patients with respiratory function impairment.


Subject(s)
Anemia, Sickle Cell/diagnostic imaging , Lung/diagnostic imaging , Tomography, X-Ray Computed/methods , Adolescent , Adult , Aged , Anemia, Sickle Cell/pathology , Anemia, Sickle Cell/physiopathology , Biomarkers/metabolism , Breath Tests/methods , Carbon Monoxide/metabolism , Female , Hemolysis/physiology , Humans , Lung/pathology , Lung/physiopathology , Male , Middle Aged , Respiratory Function Tests
16.
Surg Endosc ; 20(2): 249-51, 2006 Feb.
Article in English | MEDLINE | ID: mdl-16391960

ABSTRACT

BACKGROUND: Choledochal cyst resection and hepaticojejunostomy have historically been performed using an open technique. We describe here the largest single experience with this procedure using laparoscopic techniques in eight consecutive pediatric patients. METHODS: There were six girls and two boys, of ages ranging from 3 months to 13 years. All had type I choledochal cysts. Three were asymptomatic, having been noted on prenatal ultrasonography. Five ports were utilized: one 5-mm telescope port at the umbilicus, two 3-mm operating ports on both sides of the umbilicus, one 5-mm left subcostal port for liver retraction, and one LLQ 5-mm assistant port. RESULTS: The median operating time was 155 min (range 110-250 min), with one conversion to an open procedure due to a high transection of the cyst leading to partial retraction of the left hepatic duct into the liver substance. Mean hospital stay was 3 days. At a mean follow-up of 18.8 months, all patients were anicteric and asymptomatic. CONCLUSIONS: Laparoscopic resection of choledochal cysts can be performed safely in pediatric patients with minimal morbidity and good long-term results.


Subject(s)
Choledochal Cyst/surgery , Laparoscopy , Adolescent , Child , Child, Preschool , Female , Follow-Up Studies , Humans , Infant , Jejunostomy/methods , Laparoscopy/adverse effects , Laparoscopy/methods , Length of Stay , Male , Retrospective Studies , Time Factors , Treatment Outcome
17.
Thorax ; 59(1): 67-70, 2004 Jan.
Article in English | MEDLINE | ID: mdl-14694252

ABSTRACT

BACKGROUND: Adults with sickle cell disease (SCD) have restrictive lung function abnormalities which are thought to result from repeated lung damage caused by episodes of pulmonary vaso-occlusion; such episodes start in childhood. A study was therefore undertaken to determine whether children with SCD have restrictive lung function abnormalities and whether the severity of such abnormalities increases with age. METHODS: Sixty four children with SCD aged 5-16 years and 64 ethnic matched controls were recruited. Weight and sitting and standing height were measured, and lung function was assessed by measurement of lung volumes and forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), and peak expiratory flow (PEF) before and after bronchodilator. RESULTS: Compared with the control subjects, the children with SCD had lower mean (SD) sitting height (69 (6.3) cm v 73 (7.7) cm; p=0.004), sitting:standing height ratio (0.50 (0.02) v 0.51 (0.01); p<0.0001), weight (33 (10.9) kg v 41 (14.9) kg; p=0.001), functional residual capacity measured by a helium gas dilution technique (1.2 (0.3) l v 1.3 (0.4) l; p=0.04), FEV1 (1.5 (0.5) l v 1.9 (0.7) l; p=0.0008), FVC (1.7 (0.6) l v 2.1 (0.8) l; p=0.001), and PEF (3.9 (1.3) l/s v 4.8 (1.5) l/s; p=0.0004). The effect of age on lung function differed significantly between the children with SCD and the controls for total lung capacity and vital capacity measured by plethysmography and functional residual capacity measured by helium gas dilution. CONCLUSION: Lung function differs significantly in children with SCD compared with ethnic matched controls of a similar age. Our results suggest that restrictive abnormalities may become more prominent with increasing age.


Subject(s)
Anemia, Sickle Cell/physiopathology , Lung Diseases/physiopathology , Adolescent , Child , Child, Preschool , Female , Forced Expiratory Volume/physiology , Humans , Male , Peak Expiratory Flow Rate/physiology , Vital Capacity/physiology
18.
Arch Dis Child ; 87(4): 352-3, 2002 Oct.
Article in English | MEDLINE | ID: mdl-12244019

ABSTRACT

Height and weight were measured and body mass index (BMI) calculated in 56 sickle cell disease (SCD), 57 Caucasian (CC), and 63 African/Caribbean (AC) 3-9 year old children. The SCD children were taller, but had similar weight and BMI to the CC controls. The SCD group had lower weight and BMI than the AC controls. The AC controls were of greater height, weight, and BMI than CC controls. These data highlight the importance of using ethnically appropriate reference ranges.


Subject(s)
Anemia, Sickle Cell/complications , Black People , Growth Disorders/ethnology , Growth Disorders/etiology , White People , Aging/physiology , Anthropometry , Body Height/ethnology , Body Mass Index , Body Weight/ethnology , Child , Child, Preschool , Female , Growth Disorders/diagnosis , Humans , Male , Reference Values
19.
Future Child ; 11(1): 52-61, 2001.
Article in English | MEDLINE | ID: mdl-11712455

ABSTRACT

Families make choices about employment and care for their children in a context that is shaped by public policies and colored by public opinion. Debates over whether the government should increase funding for child care or do more to help parents stay home with their children reflect tensions among strongly held ideas about family life, work, and the role of government. This article summarizes the results of public opinion polls that probe attitudes about parent and government roles and responsibilities with respect to children's care. The polling findings yield three main lessons: The American public believes that parents should be the primary influence in their children's lives and that it is best if mothers can be home to care for the very young. The public also values family self-sufficiency and understands that low-income families may need child care assistance to balance child rearing and employment responsibilities. However, skepticism about the appropriateness of government involvement in family life limits public support for proposals that the government act directly to provide or improve child care. From these lessons, the author draws several conclusions for policymakers: Policies focused on caregiving should respect the rights of parents to raise their children by ensuring that an array of options is available. Public programs should help families who are struggling economically to balance their obligations to work and family. Rather than directly providing child care services, government should fund community-based child care programs, and provide flexible assistance to help families secure the services they need and want.


Subject(s)
Attitude , Child Care/organization & administration , Child Day Care Centers/organization & administration , Infant Care/organization & administration , Child, Preschool , Financing, Government , Humans , Infant , Infant, Newborn , Parental Leave , United States , Women, Working
20.
Respir Med ; 95(6): 526-31, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11421512

ABSTRACT

The Powerbreathe is an inspiratory muscle trainer promoted as improving inspiratory muscle strength (and consequently exercise performance) in athletes and patients with respiratory disease. No published evidence supports its efficacy. We performed a prospective randomized controlled study in which 12 normal subjects received either Powerbreathe training or sham training for a 6-week period. The primary outcome measure was diaphragm strength evaluated as twitch transdiaphragmatic pressure (Tw Pdi) but secondary outcome measures were provided by full respiratory muscle assessment and cardiopulmonary exercise testing. An advantage to training was observed when outcome was assessed by maximal static inspiratory mouth pressure (mean advantage 14.5 cm H2O, 95% CI 2.2-26.9 cm H2O, P=0.025). However. no significant difference was observed between the groups in any other parameter. In particular the deltaTw Pdi was not different between groups (mean 'advantage' 0.7 cmH2O, 95% CI- 7.0+/-5.5 cmH2O, P=0.8). The continued sale and use of the Powerbreathe device is not justified by our data. A sample size calculation showed that 234 subjects would need to be randomized to definitively refute the hypothesis that Powerbreathe improves Tw Pdi and we argue that such a study is required.


Subject(s)
Exercise Therapy/instrumentation , Respiratory Muscles/physiology , Adult , Breathing Exercises , Diaphragm/physiology , Exercise Test , Female , Humans , Male , Pressure , Statistics, Nonparametric , Treatment Outcome
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