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1.

Background and rationale

Motor fatigue and ambulation impairment are prominent clinical features of people with multiple sclerosis (pMS). We hypothesized that a multimodal and comparative assessment of walking speed on short and long distance would allow a better delineation and quantification of gait fatigability in pMS. Our objectives were to compare 4 walking paradigms: the timed 25-foot walk (T25FW), a corrected version of the T25FW with dynamic start (T25FW+), the timed 100-meter walk (T100MW) and the timed 500-meter walk (T500MW).

Methods

Thirty controls and 81 pMS performed the 4 walking tests in a single study visit.

Results

The 4 walking tests were performed with a slower WS in pMS compared to controls even in subgroups with minimal disability. The finishing speed of the last 100-meter of the T500MW was the slowest measurable WS whereas the T25FW+ provided the fastest measurable WS. The ratio between such slowest and fastest WS (Deceleration Index, DI) was significantly lower only in pMS with EDSS 4.0–6.0, a pyramidal or cerebellar functional system score reaching 3 or a maximum reported walking distance ≤4000 m.

Conclusion

The motor fatigue which triggers gait deceleration over a sustained effort in pMS can be measured by the WS ratio between performances on a very short distance and the finishing pace on a longer more demanding task. The absolute walking speed is abnormal early in MS whatever the distance of effort when patients are unaware of ambulation impairment. In contrast, the DI-measured ambulation fatigability appears to take place later in the disease course.  相似文献   

2.

Purpose

To evaluate the ability of longitudinal Useful Field of View (UFOV) and simulated driving measurements to predict future occurrence of motor vehicle collision (MVC) in drivers with glaucoma.

Design

Prospective observational cohort study.

Participants

117 drivers with glaucoma followed for an average of 2.1 ± 0.5 years.

Methods

All subjects had standard automated perimetry (SAP), UFOV, driving simulator, and cognitive assessment obtained at baseline and every 6 months during follow-up. The driving simulator evaluated reaction times to high and low contrast peripheral divided attention stimuli presented while negotiating a winding country road, with central driving task performance assessed as “curve coherence”. Drivers with MVC during follow-up were identified from Department of Motor Vehicle records.

Main Outcome Measures

Survival models were used to evaluate the ability of driving simulator and UFOV to predict MVC over time, adjusting for potential confounding factors.

Results

Mean age at baseline was 64.5 ± 12.6 years. 11 of 117 (9.4%) drivers had a MVC during follow-up. In the multivariable models, low contrast reaction time was significantly predictive of MVC, with a hazard ratio (HR) of 2.19 per 1 SD slower reaction time (95% CI, 1.30 to 3.69; P = 0.003). UFOV divided attention was also significantly predictive of MVC with a HR of 1.98 per 1 SD worse (95% CI, 1.10 to 3.57; P = 0.022). Global SAP visual field indices in the better or worse eye were not predictive of MVC. The longitudinal model including driving simulator performance was a better predictor of MVC compared to UFOV (R2 = 0.41 vs R2 = 0.18).

Conclusions

Longitudinal divided attention metrics on the UFOV test and during simulated driving were significantly predictive of risk of MVC in glaucoma patients. These findings may help improve the understanding of factors associated with driving impairment related to glaucoma.  相似文献   

3.

Background

Leprosy is an endemic infectious disease caused by Mycobacterium leprae that predominantly attacks the skin and peripheral nerves, leading to progressive impairment of motor, sensory and autonomic function. Little is known about how this peripheral neuropathy affects corticospinal excitability of handgrip muscles. Our purpose was to explore the motor cortex organization after progressive peripheral nerve injury and upper-limb dysfunction induced by leprosy using noninvasive transcranial magnetic stimulation (TMS).

Methods

In a cross-sectional study design, we mapped bilaterally in the primary motor cortex (M1) the representations of the hand flexor digitorum superficialis (FDS), as well as of the intrinsic hand muscles abductor pollicis brevis (APB), first dorsal interosseous (FDI) and abductor digiti minimi (ADM). All participants underwent clinical assessment, handgrip dynamometry and motor and sensory nerve conduction exams 30 days before mapping. Wilcoxon signed rank and Mann-Whitney tests were performed with an alpha-value of p<0.05.

Findings

Dynamometry performance of the patients’ most affected hand (MAH), was worse than that of the less affected hand (LAH) and of healthy controls participants (p = 0.031), confirming handgrip impairment. Motor threshold (MT) of the FDS muscle was higher in both hemispheres in patients as compared to controls, and lower in the hemisphere contralateral to the MAH when compared to that of the LAH. Moreover, motor evoked potential (MEP) amplitudes collected in the FDS of the MAH were higher in comparison to those of controls. Strikingly, MEPs in the intrinsic hand muscle FDI had lower amplitudes in the hemisphere contralateral to MAH as compared to those of the LAH and the control group. Taken together, these results are suggestive of a more robust representation of an extrinsic hand flexor and impaired intrinsic hand muscle function in the hemisphere contralateral to the MAH due to leprosy.

Conclusion

Decreased sensory-motor function induced by leprosy affects handgrip muscle representation in M1.  相似文献   

4.

Introduction

Polyneuropathy leads to postural instability and an increased risk of falling. We investigated how impaired motor impairment and proprioceptive input due to neuropathy influences postural strategies.

Methods

Platformless bisegmental posturography data were recorded in healthy subjects and patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). Each subject stood on the floor, wore a head and a hip electromagnetic tracker. Sway amplitude and velocity were recorded and the mean direction difference (MDD) in the velocity vector between trackers was calculated as a flexibility index.

Results

Head and hip postural sway increased more in patients with CIDP than in healthy controls. MDD values reflecting hip strategies also increased more in patients than in controls. In the eyes closed condition MDD values in healthy subjects decreased but in patients remained unchanged.

Discussion

Sensori-motor impairment changes the balance between postural strategies that patients adopt to maintain upright quiet stance. Motor impairment leads to hip postural strategy overweight (eyes open), and prevents strategy re-balancing when the sensory context predominantly relies on proprioceptive input (eyes closed).  相似文献   

5.

Background

Oxaliplatin, a platinum-based chemotherapy utilised in the treatment of colorectal cancer, produces two forms of neurotoxicity- acute sensorimotor neuropathic symptoms and a dose-limiting chronic sensory neuropathy. Given that a Na+ channelopathy has been proposed as the mechanism underlying acute oxaliplatin-induced neuropathy, the present study aimed to determine specific mechanisms of Na+ channel dysfunction.

Methodology/Principal Findings

Specifically the function of transient and persistent Na+ currents were followed during treatment and were investigated in relation to oxaliplatin dose level. Eighteen patients were assessed before and after a single oxaliplatin infusion with motor and sensory axonal excitability studies performed on the median nerve at the wrist. While refractoriness (associated with Na+ channel inactivation) was significantly altered post-oxaliplatin infusion in both motor (Pre: 31.7±6.4%; Post: 68.8±14.5%; P≤.001) and sensory axons (Pre: 31.4±5.4%; Post: 21.4±5.5%; P<.05), strength-duration time constant (marker of persistent Na+ conductances) was not significantly altered post-infusion (Motor Pre: 0.395±0.01 ms; Post: 0.394±0.02 ms; NS; Sensory Pre:0.544±0.03 ms; Post: 0.535±0.05 ms; NS). However, changes in strength-duration time constant were significantly correlated with changes in refractoriness in motor and sensory axons (Motor correlation coefficient = −.65; P<.05; Sensory correlation coefficient = .67; P<.05).

Conclusions/Significance

It is concluded that the predominant effect of acute oxaliplatin exposure in human motor and sensory axons is mediated through changes in transient rather than persistent Na+ conductances. These findings are likely to have implications for the design and trial of neuroprotective strategies.  相似文献   

6.

Introduction

The aims of this study were to assess the prevalence of dental caries and the DMFT index, as well as the distribution pattern of pit and fissure sealants on permanent teeth in a Portuguese sample of adolescents, and to assess whether the existing usage of sealants and socio-demographic factors are correlated to caries prevalence on the examined sample.

Materials and Methods

A cross-sectional study was designed with a sample of 447 adolescents aged 12 to 18 years old, attending a public school in Sátão, Portugal. A self-administered questionnaire with questions about oral health behaviours and socio-economic status was answered by adolescents in the classroom. Clinical examination of oral health status and assessment of fissure sealants were accomplished by only one trained member of the research team.

Results

We obtained a DMFT index of 3.32 (2.92), which indicates a moderate level of prevalence of dental caries. When considering a DMFT = 0, we found significant statistical differences between the parents´ level of education (≤ 4th grade = 26.3 vs 5th–12th grade = 18.8 vs <12th grade = 43.3, p = 0.001), gender (male = 27.3 vs female = 19.6, p = 0.04), age (≤15 years = 27.1 vs <15 years = 18.5, p = 0.02), presence of fissure sealants (yes = 30.6 vs no = 13.5, p = 0.001) and experience of dental pain (no = 25.4 vs yes = 16.8, p = 0.02). When analyzing the prevalence of fissure sealants, we verified that 58.8% of adolescents had at least one fissure sealant applied. Significant statistical differences were found when analyzing the presence of fissure sealants related with parents´educational level (<9th grade, OR = 1.56 CI95% = 1.05–2.54), gender (female, OR = 1.86 CI95% = 1.19–2.98), experience of dental pain (yes, OR = 0.62 CI95% = 0.39–0.97) and presence of dental caries (yes, OR = 0.35 CI95% = 0.19–0.65).

Conclusions

The moderate level of caries prevalence reveals the need of improvement of primary prevention interventions among Portuguese adolescents. The establishment of a more targeted preventive program with better and more effective oral health education is essential, having into account socio-demographic aspects.  相似文献   

7.

Introduction

Few dissemination evaluations exist to document the effectiveness of evidence-based childhood obesity interventions outside the research setting.

Objective

Evaluate Healthy Choices (HC), a multi-component obesity prevention program, by examining school-level changes in weight-related behaviors and weight status and the association of implementation components with odds of overweight/obesity.

Methods

We compared baseline and Year 3 school-level behavioral and weight status outcomes with paired t-tests adjusted for schools’ socio-demographic characteristics. We used generalized estimating equations to examine the odds of overweight/obesity associated with program components.

Setting/Participants

Consecutive sample of 45 of 51 middle schools participating in the HC program with complete baseline and follow-up survey data including a subsample of 35 schools with measured anthropomentry for 5,665 7th grade students.

Intervention

Schools developed a multi-disciplinary team and implemented an obesity prevention curriculum, before and after school activities, environmental and policy changes and health promotions targeting a 5-2-1 theme: eat ≥ 5 servings/day of fruits and vegetables (FV), watch ≤ 2 hours of television (TV) and participate in ≥ 1 hours/day of physical activity (PA) on most days

Main Outcome Measures

1) School-level percent of students achieving targeted behaviors and percent overweight/obese; and 2) individual odds of overweight/obesity.

Results

The percent achieving behavioral goals over three years increased significantly for FV: 16.4 to 19.4 (p = 0.001), TV: 53.4 to 58.2 (p = 0.003) and PA: 37.1 to 39.9 (p = 0.02), adjusting for school size, baseline mean age and percent female, non-Hispanic White, and eligible for free and reduced price lunch. In 35 schools with anthropometry, the percent of overweight/obese 7th grade students decreased from 42.1 to 38.4 (p = 0.016). Having a team that met the HC definition was associated with lower odds of overweight/obesity (OR = 0.83, CI: 0.71–0.98).

Conclusions and Relevance

The HC multi-component intervention demonstrated three-year improvements in weight-related behaviors and weight status across diverse middle schools. Team building appears important to the program’s effectiveness.  相似文献   

8.

Objective

To compare the prognostic value of fetal Doppler in dichorionic twins and singletons by measuring the interval between diagnosis of an abnormal Doppler flow and birth in fetuses who are small for gestational age (SGA).

Design

Comparative retrospective study using a prospectively collected database.

Setting

A level 3 maternity unit in France.

Population

Fetuses from singleton and dichorionic pregnancies who are SGA (vascular or unexplained), defined by an abdominal circumference (AC) measurement below the 10th percentile and confirmed by a birth weight below the 10th percentile.

Methods

Fisher''s exact and Chi-2 tests were used to compare frequencies, and the Mann-Whitney-Wilcoxon test was used to compare medians in non-Gaussian distributions.

Main outcome measures

Both neonatal outcomes and intervals between the first Doppler abnormality and birth were compared in the groups of dichorionic twins and singletons.

Results

Obstetric and neonatal outcome were similar in the 104 SGA dichorionic twins and 170 SGA singletons. Abnormalities of umbilical artery Doppler, regardless of type, appeared at the same frequency in both groups (52.9%) but were identified earlier in twins (25 versus 28 weeks, p = 0.02). Among fetuses with abnormal Doppler flow, the interval between the finding and birth was significantly longer in the twins than the singletons (44 vs 15 days, p<0.01).

Conclusions

The prognostic value of an abnormal Doppler finding for the course of a pregnancy may be different in dichorionic twins and singletons. The management of women carrying SGA twins and the information provided to them should take these results into account.  相似文献   

9.

Background

Although testosterone deficiency is associated with increased risks of heart disease, the benefits of testosterone therapy are controversial. Moreover, current understanding on the cardiac effect of testosterone during cardiac ischemia-reperfusion (I/R) periods is unclear. We tested the hypothesis that testosterone replacement attenuates the impairment of left ventricular (LV) function and heart rate variability (HRV), and reduces the infarct size and arrhythmias caused by I/R injury in orchiectomized (ORX) rats.

Methodology

ORX or sham-operated male Wistar rats (n = 24) were randomly divided and received either testosterone (2 mg/kg, subcutaneously administered) or the vehicle for 8 weeks. The ejection fraction (EF) and HRV were determined at baseline and the 4th and 8th week. I/R was performed by left anterior descending coronary artery ligation for 30 minutes, followed by a 120-minute reperfusion. LV pressure, arrhythmia scores, infarct size and cardiac mitochondrial function were determined.

Results

Prior to I/R, EF and HRV were impaired in the ORX group, but were restored in the testosterone-treated group. During I/R, arrhythmia scores and the infarct size were greater, and cardiac mitochondrial function was impaired, whereas the time to 1st VT/VF onset and the LV end-systolic pressure were decreased in the ORX group when compared to the sham group. Testosterone replacement attenuated the impairment of these parameters in ORX rats during I/R injury, but did not show any benefit or adverse effect in non-ORX rats.

Conclusions

Testosterone replacement restores cardiac function and autonomic regulation, and exerts cardioprotective effects during the I/R period via mitochondrial protection in ORX rats.  相似文献   

10.

Background

Toll-like receptors (TLRs) are critical components for host pathogen recognition and variants in genes participating in this response influence susceptibility to infections. Recently, TLR1 gene polymorphisms have been found correlated with whole blood hyper-inflammatory responses to pathogen-associated molecules and associated with sepsis-associated multiorgan dysfunction and acute lung injury (ALI). We examined the association of common variants of TLR1 gene with sepsis-derived complications in an independent study and with serum levels for four inflammatory biomarkers among septic patients.

Methodology/Principal Findings

Seven tagging single nucleotide polymorphisms of the TLR1 gene were genotyped in samples from a prospective multicenter case-only study of patients with severe sepsis admitted into a network of intensive care units followed for disease severity. Interleukin (IL)-1β, IL-6, IL-10, and C-reactive protein (CRP) serum levels were measured at study entry, at 48 h and at 7th day. Alleles -7202G and 248Ser, and the 248Ser-602Ile haplotype were associated with circulatory dysfunction among severe septic patients (0.001≤p≤0.022), and with reduced IL-10 (0.012≤p≤0.047) and elevated CRP (0.011≤p≤0.036) serum levels during the first week of sepsis development. Additionally, the -7202GG genotype was found to be associated with hospital mortality (p = 0.017) and ALI (p = 0.050) in a combined analysis with European Americans, suggesting common risk effects among studies.

Conclusions/Significance

These results partially replicate and extend previous findings, supporting that variants of TLR1 gene are determinants of severe complications during sepsis.  相似文献   

11.

Background

The mechanical characterization of infant porcine cerebellum tissue in tension at high strain rate is crucial for modeling traumatic cerebellum injury, which is in turn helpful for understanding the biomechanics of such injuries suffered in traffic accidents.

Material and Method

In this study, the infant porcine cerebellum tissue was given three loading velocities, ie, 2s-1, 20s-1 and 100s-1 with up to 30% strain to investigate the tensile properties. At least six tensile tests for each strain rate were validly performed. Fung, Gent, Ogden and exponential models were applied to fit the constitutive equations, so as to obtain material parameters from the experimental data.

Results

The Lagrange stress of infant porcine cerebellum tissue in tension appeared to be no more than 3000Pa at each loading velocity. More specifically, the Lagrange stress at 30% strain was (393.7±84.4)Pa, (928.3±56.3)Pa and (2582.4±282.2)Pa at strain rates of 2s-1, 20s-1 and 100s-1, respectively. Fung (0.833≤R2≤0.924), Gent (0.797≤R2≤0.875), Ogden (0.859≤R2≤0.944) and exponential (0.930≤R2≤0.972) models provided excellent fitting to experimental data up to 30% strain.

Conclusions

The infant cerebellum tissue shows a stiffer response with increase of the loading speed, indicating a strong strain-rate sensitivity. This study will enrich the knowledge on the material properties of infant brain tissue, which may augment the biofidelity of finite element model of human pediatric cerebellum.  相似文献   

12.

Background

Short stature was suggested as a risk factor for diabetes onset among middle age individuals, but whether this is the case among young adults is unclear. Our goal was to assess the association between height and incident diabetes among young men.

Methods and Findings

Incident diabetes was assessed among 32,055 men with no history of diabetes, from the prospectively followed young adults of the MELANY cohort. Height was measured at two time points; at adolescence (mean age 17.4±0.3 years) and grouped according to the US-CDC percentiles and at young adulthood (mean age 31.0±5.6 years). Cox proportional hazards models were applied. There were 702 new cases of diabetes during a mean follow-up of 6.3±4.3 years. There was a significant increase in the crude diabetes incidence rate with decreasing adolescent height percentile, from 4.23 cases/104 person-years in the <10th percentile group to 2.44 cases/104 person-years in the 75th≤ percentile group. These results persisted when clinical and biochemical diabetes risk factors were included in multivariable models. Compared to the 75th≤ percentile group, height below the 10th percentile was associated with a hazard ratio (HR) of 1.64 (95%CI 1.09–2.46, p = 0.017) for incident diabetes after adjustment for age, body mass index (BMI), fasting plasma glucose, HDL-cholesterol and triglyceride levels, white blood cells count, socioeconomic status, country of origin, family history of diabetes, sleep quality and physical activity. At age 30 years, each 1-cm decrement in adult height was associated with a 2.5% increase in diabetes adjusted risk (HR 1.025, 95%CI 1.01–1.04, p = 0.001).

Conclusions

Shorter height at late adolescence or young adulthood was associated with an increased risk of incident diabetes among young men, independent of BMI and other diabetes risk factors.  相似文献   

13.

Background

Aerobic exercise is associated with enhanced plasticity in the motor cortex of healthy individuals, but the effect of aerobic exercise on neuroplasticity following a stroke is unknown.

Objective

The aim of this study was to compare corticomotoneuronal excitability and neuroplasticity in the upper limb cortical representation following a single session of low intensity lower limb cycling, or a rest control condition.

Methods

We recruited chronic stroke survivors to take part in three experimental conditions in a randomised, cross-over design. Corticomotoneuronal excitability was examined using transcranial magnetic stimulation to elicit motor evoked potentials in the affected first dorsal interosseus muscle. Following baseline measures, participants either cycled on a stationary bike at a low exercise intensity for 30 minutes, or remained resting in a seated position for 30 minutes. Neuroplasticity within the motor cortex was then examined using an intermittent theta burst stimulation (iTBS) paradigm. During the third experimental condition, participants cycled for the 30 minutes but did not receive any iTBS.

Results

Twelve participants completed the study. We found no significant effect of aerobic exercise on corticomotoneuronal excitability when compared to the no exercise condition (P > 0.05 for all group and time comparisons). The use of iTBS did not induce a neuroplastic-like response in the motor cortex with or without the addition of aerobic exercise.

Conclusions

Our results suggest that following a stroke, the brain may be less responsive to non-invasive brain stimulation paradigms that aim to induce short-term reorganisation, and aerobic exercise was unable to induce or improve this response.  相似文献   

14.

Purpose

Motor unit activity is coordinated between many synergistic muscle pairs but the functional role of this coordination for the motor output is unclear. The purpose of this study was to investigate the short-term modality of coordinated motor unit activity–the synchronized discharge of individual motor units across muscles within time intervals of 5ms–for the Vastus Medialis (VM) and Lateralis (VL). Furthermore, we studied the task-dependency of intermuscular motor unit synchronization between VM and VL during static and dynamic squatting tasks to provide insight into its functional role.

Methods

Sixteen healthy male and female participants completed four tasks: Bipedal squats, single-leg squats, an isometric squat, and single-leg balance. Monopolar surface electromyography (EMG) was used to record motor unit activity of VM and VL. For each task, intermuscular motor unit synchronization was determined using a coherence analysis between the raw EMG signals of VM and VL and compared to a reference coherence calculated from two desynchronized EMG signals. The time shift between VM and VL EMG signals was estimated according to the slope of the coherence phase angle spectrum.

Results

For all tasks, except for singe-leg balance, coherence between 15–80Hz significantly exceeded the reference. The corresponding time shift between VM and VL was estimated as 4ms. Coherence between 30–60Hz was highest for the bipedal squat, followed by the single-leg squat and the isometric squat.

Conclusion

There is substantial short-term motor unit synchronization between VM and VL. Intermuscular motor unit synchronization is enhanced for contractions during dynamic activities, possibly to facilitate a more accurate control of the joint torque, and reduced during single-leg tasks that require balance control and thus, a more independent muscle function. It is proposed that the central nervous system scales the degree of intermuscular motor unit synchronization according to the requirements of the movement task at hand.  相似文献   

15.

Background

Replicating smallpox vaccines can cause severe complications in individuals with atopic dermatitis (AD). Prior studies evaluating Modified Vaccinia Ankara virus (MVA), a non-replicating vaccine in humans, showed a favorable safety and immunogenicity profile in healthy volunteers.

Objective

This Phase II study compared the safety and immunogenicity of MVA enrolling groups of 350 subjects with AD (SCORAD ≤ 30) and 282 healthy subjects.

Methods

Subjects were vaccinated twice with MVA, each dose given subcutaneously 4 weeks apart. Adverse events, cardiac parameters, and the development of vaccinia virus humoral immune responses were monitored.

Results

The overall safety of the vaccine was similar in both groups. Adverse events affecting skin were experienced significantly more often in subjects with AD, but the majority of these events were mild to moderate in intensity. Seroconversion rates and geometric mean titers for total and neutralizing vaccinia-specific antibodies in the AD group were non-inferior compared to the healthy subjects.

Limitations

The size of the study population limited the detection of serious adverse events occurring at a frequency less than 1%.

Conclusion

MVA has a favorable safety profile and the ability to elicit vaccinia-specific immune responses in subjects with AD.

Trial Registration

ClinicalTrials.gov NCT00316602  相似文献   

16.

Objectives

Our aim was to establish whether there is an interconnection between the compositional development of the gut microbiota and the amount of fussing and crying in early infancy.

Methods

Behavioral patterns of 89 infants during the 7th and 12th week of life were recorded in parental diaries. Total distress was defined as the sum of daily amounts of crying and fussing. Infants'' gut microbiota profiles were investigated by several molecular assays during the first six months of life.

Results

The median (range) duration of total distress among the infants was 106 (0–478) minutes a day during the 7th and 58 (0–448) minutes a day during the 12th week. The proportion of Bifidobacterium counts to total bacterial counts was inversely associated with the amount of crying and fussing during the first 3 months of life (p = 0.03), although the number of Bifidobacterium breve was positively associated with total distress (p = 0.02). The frequency of Lactobacillus spp. at the age of 3 weeks was inversely associated with total infant distress during the 7th week of life (p = 0.02).

Conclusions

Bifidobacterium and Lactobacillus appear to protect against crying and fussing. Identification of specific strains with optimal protective properties would benefit at-risk infants.  相似文献   

17.

Background

Water Sensitive Urban Design (WSUD) systems are frequently used as part of a stormwater harvesting treatment trains (e.g. biofilters (bio-retentions and rain-gardens) and wetlands). However, validation frameworks for such systems do not exist, limiting their adoption for end-uses such as drinking water. The first stage in the validation framework is pre-validation, which prepares information for further validation monitoring.

Objectives

A pre-validation roadmap, consisting of five steps, is suggested in this paper. Detailed methods for investigating target micropollutants in stormwater, and determining challenge conditions for biofilters and wetlands, are provided.

Methods

A literature review was undertaken to identify and quantify micropollutants in stormwater. MUSIC V5.1 was utilized to simulate the behaviour of the systems based on 30-year rainfall data in three distinct climate zones; outputs were evaluated to identify the threshold of operational variables, including length of dry periods (LDPs) and volume of water treated per event.

Results

The paper highlights that a number of micropollutants were found in stormwater at levels above various worldwide drinking water guidelines (eight pesticides, benzene, benzo(a)pyrene, pentachlorophenol, di-(2-ethylhexyl)-phthalate and a total of polychlorinated biphenyls). The 95th percentile LDPs was exponentially related to system design area while the 5th percentile length of dry periods remained within short durations (i.e. 2–8 hours). 95th percentile volume of water treated per event was exponentially related to system design area as a percentage of an impervious catchment area.

Conclusions

The out-comings of this study show that pre-validation could be completed through a roadmap consisting of a series of steps; this will help in the validation of stormwater treatment systems.  相似文献   

18.
Qiu MZ  Qiu HJ  Wang ZQ  Ren C  Wang DS  Zhang DS  Luo HY  Li YH  Xu RH 《PloS one》2012,7(2):e31736

Background

In this study, we established a hypothetical tumor-lodds-metastasis (TLM) and tumor-ratio-metastasis (TRM) staging system. Moreover, we compared them with the 7th edition of American Joint Committee on Cancer tumor-nodes-metastasis (AJCC TNM) staging system in gastric cancer patients after D2 resection.

Methods

A total of 1000 gastric carcinoma patients receiving treatment in our center were selected for the analysis. Finally, 730 patients who received D2 resection were retrospectively studied. Patients were staged using the TLM, TRM and the 7th edition AJCC TNM system. Survival analysis was performed with a Cox regression model. We used two parameters to compare the TNM, TRM and TLM staging system, the −2log likelihood and the hazard ratio.

Results

The cut points of lymph node ratio (LNR) were set as 0, 0–0.3, 0.3–0.6, 0.6–1.0. And for the log odds of positive lymph nodes (LODDS), the cut points were established as≤−0.5, −0.5-0, 0-0.5, >0.5. There were significant differences in survival among patients in different LODDS classifications for each pN or LNR groups. When stratified by the LODDS classifications, the prognosis was highly homologous between those in the according pN or LNR classifications. Multivariate analysis showed that TLM staging system was better than the TRM or TNM system for the prognostic evaluation.

Conclusions

The TLM system was superior to the TRM or TNM system for prognostic assessment of gastric adenocarcinoma patients after D2 resection.  相似文献   

19.
《PloS one》2015,10(11)

Background

Changes in criteria and differences in populations studied and methodology have produced a wide range of prevalence estimates for mild cognitive impairment (MCI).

Methods

Uniform criteria were applied to harmonized data from 11 studies from USA, Europe, Asia and Australia, and MCI prevalence estimates determined using three separate definitions of cognitive impairment.

Results

The published range of MCI prevalence estimates was 5.0%–36.7%. This was reduced with all cognitive impairment definitions: performance in the bottom 6.681% (3.2%–10.8%); Clinical Dementia Rating of 0.5 (1.8%–14.9%); Mini-Mental State Examination score of 24–27 (2.1%–20.7%). Prevalences using the first definition were 5.9% overall, and increased with age (P < .001) but were unaffected by sex or the main races/ethnicities investigated (Whites and Chinese). Not completing high school increased the likelihood of MCI (P ≤ .01).

Conclusion

Applying uniform criteria to harmonized data greatly reduced the variation in MCI prevalence internationally.  相似文献   

20.

Objectives

To investigate whether skin-to-stone distance (SSD), which remains controversial in patients with ureter stones, can be a predicting factor for one session success following extracorporeal shock wave lithotripsy (ESWL) in patients with upper ureter stones.

Patients and Methods

We retrospectively reviewed the medical records of 1,519 patients who underwent their first ESWL between January 2005 and December 2013. Among these patients, 492 had upper ureter stones that measured 4–20 mm and were eligible for our analyses. Maximal stone length, mean stone density (HU), and SSD were determined on pretreatment non-contrast computed tomography (NCCT). For subgroup analyses, patients were divided into four groups. Group 1 consisted of patients with SSD<25th percentile, group 2 consisted of patients with SSD in the 25th to 50th percentile, group 3 patients had SSD in the 50th to 75th percentile, and group 4 patients had SSD≥75th percentile.

Results

In analyses of group 2 patients versus others, there were no statistical differences in mean age, stone length and density. However, the one session success rate in group 2 was higher than other groups (77.9% vs. 67.0%; P = 0.032). The multivariate logistic regression model revealed that shorter stone length, lower stone density, and the group 2 SSD were positive predictors for successful outcomes in ESWL. Using the Bayesian model-averaging approach, longer stone length, lower stone density, and group 2 SSD can be also positive predictors for successful outcomes following ESWL.

Conclusions

Our data indicate that a group 2 SSD of approximately 10 cm is a positive predictor for success following ESWL.  相似文献   

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