Cumulative Contact Research Articles

Cumulative Effects of Prior Concussion and Primary Sport Participation on Brain Morphometry in Collegiate Athletes: A Study From the NCAA-DoD CARE Consortium.

Prior studies have reported long-term differences in brain structure (brain morphometry) as being associated with cumulative concussion and contact sport participation. There is emerging evidence to suggest that similar effects of prior concussion and contact sport participation on brain morphometry may be present in younger cohorts of active athletes. We investigated the relationship between prior concussion and primary sport participation with subcortical and cortical structures in active collegiate contact sport and non-contact sport athletes. Contact sport athletes (CS; N = 190) and matched non-contact sport athletes (NCS; N = 95) completed baseline clinical testing and participated in up to four serial neuroimaging sessions across a 6-months period. Subcortical and cortical structural metrics were derived using FreeSurfer. Linear mixed-effects (LME) models examined the effects of years of primary sport participation and prior concussion (0, 1+) on brain structure and baseline clinical variables. Athletes with prior concussion across both groups reported significantly more baseline concussion and psychological symptoms (all ps < 0.05). The relationship between years of primary sport participation and thalamic volume differed between CS and NCS (p = 0.015), driven by a significant inverse association between primary years of participation and thalamic volume in CS (p = 0.007). Additional analyses limited to CS alone showed that the relationship between years of primary sport participation and dorsal striatal volume was moderated by concussion history (p = 0.042). Finally, CS with prior concussion had larger hippocampal volumes than CS without prior concussion (p = 0.015). Years of contact sport exposure and prior concussion(s) are associated with differences in subcortical volumes in young-adult, active collegiate athletes, consistent with prior literature in retired, primarily symptomatic contact sport athletes. Longitudinal follow-up studies in these athletes are needed to determine clinical significance of current findings.

Fitness of the Generalized Growth to the COVID-19 Data

A generalized growth model is applied to fit the time series of cumulative confirmed cases between Jan. 15 to Feb. 15, 2020. Moreover, the same formula is also applied to the time series of cumulative susceptive cases and cumulative close contact cases from Jan. 23 to Feb. 15, 2020. The model tallies with data published by the National Health Commission. The sub-exponential and sub-linear growth reflect the time heterogeneity during the transmission of COVID-19, which provide the reference to the prediction of the growth trend of the transmission.

Influencing Factors on COVID-19 Infection Despite Protective Measures Among Orthopedic Residents: Air Ventilation and Contact Duration.

Despite all protective measures, the number of contacts and cumulative contact duration in the frontline screening seem to be the influencing factors. Three out 5 of our first year orthopedic residents showed symptoms of the disease 2-3 weeks after starting their tasks in the COVID-19 floor. Other residents that were only visiting patients in the COVID floor did not become symptomatic which also highlights the role of ventilation. We assumed that the ventilation in the Emergency Screening area was not as efficient as the COVID floors and ICUs because only the residents visiting patients in the frontline became symptomatic. The bright side of this scenario was that the symptoms were mild with no or minimal pathology on chest X-ray, which deemed unlikely if the protective measures were insufficient as mortalities were high among providers in the beginning of the crises.

Clinical characteristics of 30 medical workers infected with new coronavirus pneumonia

Objective: To investigate the clinical characteristics of medical staff with novel coronavirus pneumonia(NCP). Methods: 30 patients infected with novel coronavirus referred to jianghan university hospital between January 11, 2020 and January 3, 2020 were studied. The data reviewed included those of clinical manifestations, laboratory investigation and Radiographic features. Results: The patients consisted of 10 men and 20 women, including 22 doctors and 8 nurses,aged 21~59 years(mean 35±8 years).They were divided to 26 common type and 4 severe cases, all of whom had close(within 1m) contact with patients infected of novel coronavirus pneumonia. The average contact times were 12 (7,16) and the average cumulative contact time was 2 (1.5,2.7) h.Clinical symptoms of these patients were fever in 23 patients (76.67%) , headache in 16 petients (53.33%) , fatigue or myalgia in 21patients (70%) , nausea, vomiting or diarrhea in 9 petients (30%) , cough in 25 petients (83.33%) , and dyspnea in 14 petients (46.67%) .Routine blood test revealed WBC <4.0×10(9)/L in 8 petients (26.67%) , (4-10) ×10(9)/L in 22 petients (73.33%) , and WBC>4.0×10(9)/L in 4 petients (13.33%) during the disease.Lymphocyte count <1.0×10(9)/L occurred in 12 petients (40%),abnormal liver function in 7 petients (23.33%) ,myocardial damage in 5 petients(16.67%), elevated D-dimer (>0.5mg/l) in 5 patients (16.67%). Compared with normal patients, the average exposure times, cumulative exposure time, BMI, Fever time, white blood cell count, liver enzyme, LDH, myoenzyme and D-dimer were significantly increased in severe patients, while the lymphocyte count and albumin levels in peripheral blood were significantly decreased.Chest CT mainly showed patchy shadows and interstitial changes.According to imaging examination, 11 patients (36.67%) showed Unilateral pneumonia and 19 patients (63.33%) showed bilateral pneumonia,4 patients (13.33%) showed bilateral multiple mottling and ground-glass opacity.Compared with the patients infected in the protected period, the proportion of severe infection and bilateral pneumonia were both increased in the patients infected in unprotected period. Conclusion: Medical staffs are at higher risk of infection.Infection rates are associated with contact time, the amount of suction virus. Severe patients had BMI increased, heating time prolonged , white blood cell count, lymphocyte count, D-dimer and albumin level significantly changed and were prone to be complicated with liver damage and myocardial damage.Strict protection measures is important to prevent infection for medical workers.

Hand Hygiene Practices and Risk and Prevention of Hand Eczema during the COVID-19 Pandemic.

Hand Hygiene Practices and Risk and Prevention of Hand Eczema during the COVID-19 Pandemic.

Pattern of lower leg and foot eczema in patients attending a tertiary care hospital in North East India

Pattern of lower leg and foot eczema in patients attending a tertiary care hospital in North East India - IJCED- Print ISSN No: - 2581-4710 Online ISSN No:- 2581-4729 Article DOI No:- 10.18231/j.ijced.2019.066, IP Indian Journal of Clinical and Experimental Dermatology-IP Indian J Clin Exp Dermatol

Clinical evaluation of common allergens in contact dermatitis to cement

&lt;p class="abstract"&gt;&lt;strong&gt;Background:&lt;/strong&gt; Cement is the most common cause of occupational dermatitis in construction industry. Skin contact with cement results in irritant contact dermatitis ranging from cement burns to chronic cumulative irritant contact dermatitis. Chromate, cobalt, nickel, epoxy resins and rubber chemicals are the important allergens in construction workers. The objective of the study was to study various clinical pattern of distribution and association between the duration of exposure to cement and clinical manifestation in occupational group.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Methods:&lt;/strong&gt; 107 cases of contact dermatitis with history of exposure to cement attending the occupational contact dermatitis outpatient department, Department of Dermatology, Rajiv Gandhi Government General Hospital and college, All the patients were subjected to blood investigation such as complete hemogram, liver function test, renal function test and absolute eosinophil count. Patient with history and clinical features suggestive of contact dermatitis due to cement were patch tested.&lt;strong&gt;&lt;/strong&gt;&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Results:&lt;/strong&gt; Among 107 patients, the most common pattern of involvement includes extremities which account for 64 patients (59.8%) Involvement of face, neck, trunk and extremities was seen in 11 patients (10.3%). Among 81 positive patch test patients, chromium was positive in 78 patients (96.3%) followed by epoxy resin in 14 patients 17.3% and cobalt and thiuram mix in 9 patients (11.1%) each and the least was black rubber mix in 3 patients (3.7%).&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Conclusions:&lt;/strong&gt; This study emphasizes the need for standardization in the chrome content of cement. Strict workplace safety guidelines should be implemented from government to protect workers from developing contact dermatitis to cement. &lt;/p&gt;

Contacts of healthcare workers, patients and visitors in general wards in Singapore.

To characterize contacts in general wards, a prospective survey of healthcare workers (HCWs), patients and visitors was conducted using self-reported diary, direct observation and telephone interviews. Nurses, doctors and assorted HCWs reported a median of 14, 18 and 15 contact persons over one work shift, respectively. Within 1 h, we observed 3·5 episodes with 25·6 min of cumulative contact time for nurses, 2·9 episodes and 22·1 min for doctors and 5·0 episodes with 44·3 min for assorted-HCWs. In interactions with patients, nurses had multiple brief episodes of contact; doctors had fewer episodes and less cumulative contact time; assorted-HCWs had fewer contact episodes of longer durations (than for nurses and doctors). Assortative mixing occurred amongst HCWs: those of the same HCW type were the next most frequent class of contact after patients. Over 24-h, patients contacted 14 persons with 23 episodes and 314·5 min of contact time. Patient-to-patient contact episodes were rare, but a maximum of five were documented from one patient participant. 22·9% of visitors reported contact with patients other than the one they visited. Our study revealed differences in the characteristics of contacts among different HCW types and potential transmission routes from patients to others within the ward environment.

Soil iron and aluminium concentrations and feet hygiene as possible predictors of Podoconiosis occurrence in Kenya.

BackgroundPodoconiosis (mossy foot) is a neglected non-filarial elephantiasis considered to be caused by predisposition to cumulative contact of uncovered feet to irritative red clay soil of volcanic origins in the tropical regions. Data from structured observational studies on occurrence of Podoconiosis and related factors are not available in Kenya.Methodology/Principal findingsTo establish the occurrence and aspects associated with Podoconiosis, a cross-sectional survey was implemented in an area located within 30 km from the foot of volcanic Mount Longonot in the Great Rift Valley in Kenya. Five villages and 385 households were selected using multistage and systematic random sampling procedures respectively during the survey. Podoconiosis was determined by triangulating (1) the clinical diagnosis, (2) molecular assaying of sputum samples to rule out Wuchereria bancrofti microfilaria and (3) determining the concentration of six elements and properties in the soil known to be associated with Podoconiosis. A structured questionnaire was used to identify possible risk factors. Univariable and multivariable Poisson regression analyses were carried out to determine factors associated with Podoconiosis. Thirteen participants were clinically positive for Podoconiosis giving an overall prevalence of 3.4%. The prevalence ranged between 0% and 18.8% across the five villages. Molecular assay for W. bancrofti test turned negative in the 13 samples. The following factors were positively associated with the Podoconiosis prevalence (P<0.1) in the univariable analyses: (i) age, (ii) gender, (iii) education level, (iv) frequency of washing legs, (v) frequency of wearing shoes, (vi) soil pH, and (vii) village. Unexpectedly, the concentration of soil minerals previously thought to be associated with Podoconiosis was found to be negatively associated with the Podoconiosis prevalence (P<0.1). In the multivariable analyses, only frequency of wearing shoes and village turned out significant (P≤0.05). By modeling the different soil mineral concentrations and pH while adjusting for the variable frequency of wearing shoes, only iron concentration was significant and in the negative dimension (P≤0.05). However, controlling for Iron, Aluminum concentrations turned significant.Conclusion/SignificanceThis study has pointed to a hitherto unreported occurrence of Podoconiosis cases and has contributed to the baseline knowledge on the occurrence of Podoconiosis in Kenya. Consistent with many studies, wearing shoes remain an important risk factor for the occurrence of the disease. However, our findings are inconsistent with some of the hitherto postulations that associate Podoconiosis prevalence with certain minerals in the soil in other regions in Africa. These findings provide new beginnings for the cross-disciplinary research of Podoconiosis in environmental health, socio-ecology and ecological niche and geo-spatial modeling and prediction.

Effects of individual popularity on information spreading in complex networks

In real world, human activities often exhibit preferential selection mechanism based on the popularity of individuals. However, this mechanism is seldom taken into account by previous studies about spreading dynamics on networks. Thus in this work, an information spreading model is proposed by considering the preferential selection based on individuals’ current popularity, which is defined as the number of individuals’ cumulative contacts with informed neighbors. A mean-field theory is developed to analyze the spreading model. Through systematically studying the information spreading dynamics on uncorrelated configuration networks as well as real-world networks, we find that the popularity preference has great impacts on the information spreading. On the one hand, the information spreading is facilitated, i.e., a larger final prevalence of information and a smaller outbreak threshold, if nodes with low popularity are preferentially selected. In this situation, the effective contacts between informed nodes and susceptible nodes are increased, and nodes almost have uniform probabilities of obtaining the information. On the other hand, if nodes with high popularity are preferentially selected, the final prevalence of information is reduced, the outbreak threshold is increased, and even the information cannot outbreak. In addition, the heterogeneity of the degree distribution and the structure of real-world networks do not qualitatively affect the results. Our research can provide some theoretical supports for the promotion of spreading such as information, health related behaviors, and new products, etc.

Occupational Hand Eczema among Cement users in Nepal

Background: Occupational dermatitis among cement workers is a major occupational health concern and skin contact with cement has been associated with contact dermatitis, which ranges from cement burns to cumulative irritant contact dermatitis. Objective: The objective of this study was to investigate the prevalence and severity of occupational cement contact dermatitis amongst cement workers in Nepal which is the first of its kind. Methods: A cross sectional descriptive study amongst patients in construction site and hardware shops within the Kathmandu valley were selected. A structured questionnaire was used to evaluate the demographic data and work-related activities of these cement workers. A complete skin examination was conducted and skin manifestations were assessed by a dermatologist. The data collected was compiled and appropriate statistical tools was used to find out the significance of variables. Result: Out of the total number of workers screened 164/377 (43.50%) had hand contact dermatitis. There were males 148(90.2%) and females16 (9.8%) and the age ranged from 15-51 years ( mean 27.41± 7.68 years).The duration of the disease ranged from 1-360 months (median 36months (IQR=60).The most common site of lesion was palms (62.8%) followed by tip of the fingers in 39.0% patients and the most common morphology of the lesion was erythema seen in 59.1% followed by scaling seen in 51.8 % patients. Conclusion: The issue of contact and irritant hand eczema amongst cement workers in Nepal has had a considerable morbidity. Identification of these patients with adequate treatment, test of the suspected allergens and counseling could further help the patients involved.

Does Game Participation Impact Cognition and Symptoms in Elite Football Players?

To measure neurocognitive functioning in college and professional football players after game participation. Retrospective, cross-sectional cohort design. Ninety-four male university and professional football players. All participants completed Immediate Postconcussion Assessment and Cognitive Testing (ImPACT) testing at baseline, and either at postconcussion (group 1) or postgame (group 2) participation. Results from the 5 ImPACT composite scores (Verbal Memory, Visual Memory, Visual Motor Speed, Reaction Time and Impulse Control) and Total Symptom Score. Repeated-measures analysis of variance demonstrated a significant main effect for time (improvements) in 3 of 5 domains for the postconcussion group, but no improvements in the postgame group. The postconcussion group presented with significantly improved results on 4 of 5 ImPACT domains compared with the postgame group at the follow-up time interval. Participation in a football game with potential cumulative head contacts did not yield increased symptoms or cognitive impairment. However, the absence of improvement in cognitive functioning in noninjured football players, which was found in those players who were returned to play after an injury, may suggest that there is a measureable impact as a result of playing football.

Associations Between Incarcerated Fathers’ Cumulative Childhood Risk and Contact With Their Children

Incarcerated fathers often experience early life risk factors that cumulate over time and are compounded by the negative repercussions of imprisonment. These dynamics may contribute to the intergenerational transmission of risk and help explain the persistent link between paternal incarceration and poor child outcomes. Contact between incarcerated fathers and their children can benefit them both, but there is limited research on the factors that affect father–child contact. Using data from the 2004 Survey of Inmates in State Correctional Facilities and a sample of fathers with at least one minor child ( N = 5,809), the authors found that incarcerated fathers who experienced more childhood risk factors had less frequent contact with their children. A variety of inmate characteristics were also significant predictors of father–child contact. Parenting interventions could address incarcerated fathers’ childhood risk experiences, which likely undermine the development and maintenance of family relationships, to help them develop prosocial skills.

Characteristics of quasi-liquid metal layer in the cumulative jet and barrier contact zone

According to the known experimental data on explosive metal processing, as well as the theoretical and experimental studies on the sintered metal powders, we estimated the minimum pressure and temperature values at which this layer and its thickness are formed. The study used a hypothetical model of forming a quasi-liquid metal layer between the leader of the cumulative jet, and a barrier at the time of its destruction.

Contacts between health care workers and patients in a short-stay geriatric unit during the peak of a seasonal influenza epidemic compared with a nonepidemic period

Patterns of contacts between health care workers and patients during seasonal epidemics are unknown. Our study objective was to compare the number and duration of contacts between health care workers and patients during a nonepidemic period versus a community influenza epidemic, and to identify supercontactors. Our observational study was conducted in a short-stay geriatric unit of a university hospital. Contacts between individuals were recorded by active radio frequency identification devices. Contact patterns were compared between 2 periods according to contact number and duration. Each care period lasted 5 days in the nonepidemic and influenza epidemic periods. The study included 21 medical doctors, 43 nurses, and 56 patients. In total, 3,200 contacts (61.4%; 152,700 seconds) were recorded during the nonepidemic period, with 2,013 contacts (38.6%; 92,740 seconds) in the epidemic period (P = .007). More cumulative contacts occurred during the nonepidemic period between nurses and patients (n = 2,638 [82%] vs n = 1,599 [79%]), but not between patients (n = 56 [18%] vs n = 414 [21%]). Contact duration between nurses and patients lasted longer during the nonepidemic period (P = .04). During the epidemic period, 6 nurses (15%) considered to be supercontactors accounted for 44.3% of the total number of contacts with patients. The pattern of contacts between individuals differed according to the presence or not of the community influenza peak that might have influenced the risk of nosocomial influenza.

The shape of the hip joint as a risk factor for osteoarthritis

Purpose: Cam-type femoroacetabular impingement characterized by extra bone formation at the anterolateral head-neck junction of the hip creates a non-spherical femoral head, known as a cam deformity. The cam deformity is forced into the acetabulum during flexion and internal rotation of the hip, leading to structural damage as acetabular labrum tears and cartilage delamination. This damage might gradually lead to osteoarthritis. Cam deformity and subtle acetabular dysplasia are recently recognized as relevant risk factors for hip osteoarthritis (HOA). In subtle acetabular dysplasia, the femoral head has contact with a small area of the shallowacetabulum. Therefore, more focal stress is put on this small area, which provides insufficient coverage for the femur. Cumulative articular surface contact stress above a critical threshold in dysplastic joints causes joint degeneration. However, the influence of these deformities on HOA incidence compared with other risk factors including age, gender, and body mass index (BMI) and the effect modification of other known determinants on these associations are not yet known. Methods: Participants of Rotterdam Study (RS-I: n = 2960, RS-II: n = 1470) including men and women aged >55 years with a Kellgren and Lawrence (K/L) grade ≥1 at baseline and mean follow-up of 9.2 years were included in the study. Incident radiographic HOA was defined as a K/L grade of ≥2 or a total joint replacement at follow-up. The shape of the proximal femur and the acetabulumwere outlined by a set of points (23 points, Figure 1) that were positioned on pre-defined anatomical landmarks on the anteroposterior pelvic radiographs using statistical shape modeling software. Using this point set, alpha and center-edge (CE) angles, parameters that quantify these deformities were calculated. Acetabular dysplasia and cam deformity were defined as the presence of a CE angle 60°, respectively (Figure 1). Using generalized estimating equation models, odds ratios were calculated to assess the associations between both hip deformities and the development of HOA. Results: At the follow-up times, 234 and 179 cases of HOAwere identified for RS-I and RS-II, respectively. Incident OA was defined in 281 hips within RS-I among that 12.2% (n = 34) had cam deformity and 8.3% (n = 23) had acetabular dysplasia, while out of 218 hips with incident OA in RS-II,16.1% (n = 35) had cam deformity and 7.3% (n = 16) had dysplasia. In pooled data analyses (Table 1), individuals with cam deformity had a two-fold increased risk for developing osteoarthritis (OR = 2.0, 95% CI= 1.48-2.71, p = 0.00001) compared with individuals without cam deformity. Moreover, subtle acetabular dysplasia was significantly associated with increased risk of HOA (OR = 1.96, 95% CI = 1.35-2.84, p = 0.0004). Both associations were independent of known risk factors of HOA such as age, sex, and BMI and were only significantly associated with development of OA in younger individuals. These bony deformities were independently related to the outcomewhen included in the samemodel (camdeformity: OR (95% CI) = 2.03 (1.50-2.76), hip dysplasia: OR (95% CI) = 2.03 (1.41-2.92)). The results were almost consistent in both cohorts. Conclusions: Individuals with cam deformity and acetabular dysplasia are strongly predisposed to progression to HOA independently from other well known risk factors of age, sex, and BMI. Interestingly, both deformities were only predisposing to OA in relatively young individuals. Therefore, early identification of these conditions is important and might provide an opportunity to prevent hip osteoarthritis. (Figure Presented).

Changes in tibiofemoral contact forces during running in response to in-field gait retraining

ABSTRACTWe evaluated the efficacy of an in-field gait retraining programme using mobile biofeedback to reduce cumulative and peak tibiofemoral loads during running. Thirty runners were randomised to either a retraining group or control group. Retrainers were asked to increase their step rate by 7.5% over preferred in response to real-time feedback provided by a wrist mounted running computer for 8 routine in-field runs. An inverse dynamics driven musculoskeletal model estimated total and medial tibiofemoral joint compartment contact forces. Peak and impulse per step total tibiofemoral contact forces were immediately reduced by 7.6% and 10.6%, respectively (P < 0.001). Similarly, medial tibiofemoral compartment peak and impulse per step tibiofemoral contact forces were reduced by 8.2% and 10.6%, respectively (P < 0.001). Interestingly, no changes were found in knee adduction moment measures. Post gait retraining, reductions in medial tibiofemoral compartment peak and impulse per step tibiofemoral contact force were still present (P < 0.01). At the 1-month post-retraining follow-up, these reductions remained (P < 0.05). With these per stance reductions in tibiofemoral contact forces in mind, cumulative tibiofemoral contact forces did not change due to the estimated increase in number of steps to run 1 km.

Leaching behaviour of hexabromocyclododecane from treated curtains.

A series of laboratory experiments were conducted, whereby two HBCDD treated polyester curtain samples were contacted with deionised Milli-Q water as leaching fluid and HBCDD determined in the resulting leachate. As well as single batch (no replenishment of leaching fluid), serial batch (draining of leachate and replenishment with fresh leaching fluid at various time intervals) experiments were conducted. In single batch experiments at 20 °C, ΣHBCDD concentrations increased only slightly with increasing contact time (6 h, 24 h, and 48 h). This is supported by serial batch tests at 20 °C in which leaching fluid was replaced after 6 h, 24 h, 48 h, 72 h, 96 h, and 168 h. Data from these experiments show that while concentrations of HBCDD in leachate after 24 h cumulative contact time exceed those at 6 h; concentrations in samples collected at subsequent contact times remained steady at ∼50% of those in the 24 h sample. Consistent with this, leaching is shown to be second order, whereby a period of initially intense dissolution of more labile HBCDD is followed by a slower stage corresponding to external diffusion of the soluble residue within the textile. In experiments conducted at 20 °C, α-HBCDD is preferentially leached compared to β- and γ-HBCDD. However, at higher temperatures, the relatively more hydrophobic diastereomers are proportionally more readily leached, i.e. raising the temperature from 20 °C to 80 °C increased concentrations of γ-HBCDD in the leachate by a factor of 28-33 while corresponding α-HBCDD concentrations only increased by a factor of 4.3-4.8.

Participation rates, response bias and response behaviours in the community survey of the Swiss Spinal Cord Injury Cohort Study (SwiSCI).

BackgroundSurveying persons with disabilities is challenging, as targeted subjects may experience specific barriers to survey participation. Here we report on participation rates and response behaviour in a community survey of people with spinal cord injury (SCI) in Switzerland. The cross-sectional survey was implemented as part of the Swiss Spinal Cord Injury Cohort Study (SwiSCI) and represents the largest population-based SCI survey in Europe including nearly 2000 persons. Design features to enhance participation rates included the division of the questionnaire volume over three successive modules; recurrent and mixed-mode reminding of non-responders; and mixed-mode options for response.MethodsWe describe participation rates of the SwiSCI community survey (absolute and cumulative cooperation, contact, response, and attrition rates) and report on response rates in relation to recruitment efforts. Potential non-response bias and the association between responders’ characteristics and response behaviour (response speed: reminding until participation; response mode: paper-pencil vs. online completion) were assessed using regression modelling.ResultsOver the successive modules, absolute response rates were 61.1, 80.6 and 87.3 % which resulted in cumulative response rates of 49.3 and 42.6 % for the second and third modules. Written reminders effectively increased response rates, with the first reminder showing the largest impact. Telephone reminders, partly with direct telephone interviewing, enhanced response rate to the first module, but were essentially redundant in subsequent modules. Non-response to the main module was related to current age, membership of Swiss Paraplegic Association (SPA) and time since injury, but not to gender, lesion level and preferred language of response. Response speed increased with household income, but was not associated to other sociodemographic factors, lesion characteristics or health indicators. We found significant associations between online completion and male gender, younger age, higher education, higher income, SPA membership, tetraplegia, longer time since injury, higher quality of life, and more participation restrictions.ConclusionIn this sample with little non-response bias, recurrent and mixed-mode reminding and mixed-mode options for response were key features of optimizing survey design.

DFCT: A New Data Forwarding Algorithm Based on Cumulative Performance and Transient Performance in DTNs

Delay Tolerant Networks (DTNs) are lack of end-to-end links. In order to overcome the frequent link interrupt, DTNs are often the store-carry-forwarding mechanism. Most routing forwarding algorithm only consider cumulative contact situation between network node and destination node, but in DTNs the frequent change of network topology can cause a lot of transient contact situation between network node and destination node. In order to make the fullest use of these transient contact situations, this paper proposes a new data forwarding algorithm based on cumulative performance and transient performance. It combines the cumulative performance and transient conditions between network node and destination node. We can choose a better relay node, so as to more efiectively improve the network performance. Then we use a realistic trace flle for simulation experiment, and compared with the two classic routing algorithms of Epidemic and Label. The experimental results show that the proposed algorithm can obviously reduce the network overhead compared with Epidemic algorithm and Label algorithm, and is close to the maximum delivery rate obtained by Epidemic algorithm.