Sex differences in physical functioning among older adults: cross-sectional results from the OUTDOOR ACTIVE study.

BACKGROUND: Maintaining good functional ability is a key component of healthy ageing and a basic requirement for carrying out activities of daily living, staying independent, and delaying admission to a nursing home. Even though women have a higher life expectancy and slower age-related muscle mass loss than men, they often show a higher prevalence of limitations in physical functioning. However, the reasons behind these sex differences are still unclear. Therefore, the aims of this study were to investigate sex differences among older adults regarding physical functioning and to study which factors are explaining these sex differences. METHODS: Cross-sectional data from participants of the OUTDOOR ACTIVE study residing in Bremen, Germany, aged 65 to 75 years, were included in the analyses. Physical functioning was assessed via a self-administered questionnaire using the SF-36 10-item Physical Functioning Scale. Social, lifestyle, and health-related factors were also assessed using the questionnaire. Physical activity was measured objectively using wrist-worn accelerometers over seven consecutive days. Descriptive analyses with absolute and relative frequencies, means and standard deviations, as well as T-tests and chi-square tests were carried out. To test for associations between sex, physical functioning, and several individual factors, linear regressions were performed. RESULTS: Data of 2 141 participants (52.1% female) were included in the study. Women and men showed statistically significant differences in physical functioning, with men perceiving fewer limitations than women. On average, women had a physical functioning score of 81.4 ± 19.3 and men 86.7 ± 17.0. Linear regression showed a statistically significant negative association between physical functioning score and sex (ß: -0.15, 95% CL: -0.19, -0.10). The association remained statistically significant when adding individual factors to the model. All factors together were only able to explain 51% of the physical functioning-sex association with health indicators and the presence of chronic diseases being the most influential factors. CONCLUSIONS: We found sex differences in physical functioning, with older women having more limitations than older men. The results showed that health-related factors and chronic diseases played the biggest roles in the different physical functioning scores of women and men. These findings contribute to future longitudinal, more in-depth research. TRIAL REGISTRATION: German Clinical Trials Register DRKS00015117 (Date of registration 17-07-2018).

Safeguarding human-wildlife cooperation.

Human-wildlife cooperation occurs when humans and free-living wild animals actively coordinate their behavior to achieve a mutually beneficial outcome. These interactions provide important benefits to both the human and wildlife communities involved, have wider impacts on the local ecosystem, and represent a unique intersection of human and animal cultures. The remaining active forms are human-honeyguide and human-dolphin cooperation, but these are at risk of joining several inactive forms (including human-wolf and human-orca cooperation). Human-wildlife cooperation faces a unique set of conservation challenges, as it requires multiple components-a motivated human and wildlife partner, a suitable environment, and compatible interspecies knowledge-which face threats from ecological and cultural changes. To safeguard human-wildlife cooperation, we recommend: (i) establishing ethically sound conservation strategies together with the participating human communities; (ii) conserving opportunities for human and wildlife participation; (iii) protecting suitable environments; (iv) facilitating cultural transmission of traditional knowledge; (v) accessibly archiving Indigenous and scientific knowledge; and (vi) conducting long-term empirical studies to better understand these interactions and identify threats. Tailored safeguarding plans are therefore necessary to protect these diverse and irreplaceable interactions. Broadly, our review highlights that efforts to conserve biological and cultural diversity should carefully consider interactions between human and animal cultures. Please see AfricanHoneyguides.com/abstract-translations for Kiswahili and Portuguese translations of the abstract.

AI for Doctors-A Course to Educate Medical Professionals in Artificial Intelligence for Medical Imaging.

Successful adoption of artificial intelligence (AI) in medical imaging requires medical professionals to understand underlying principles and techniques. However, educational offerings tailored to the need of medical professionals are scarce. To fill this gap, we created the course "AI for Doctors: Medical Imaging". An analysis of participants' opinions on AI and self-perceived skills rated on a five-point Likert scale was conducted before and after the course. The participants' attitude towards AI in medical imaging was very optimistic before and after the course. However, deeper knowledge of AI and the process for validating and deploying it resulted in significantly less overoptimism with respect to perceivable patient benefits through AI (p = 0.020). Self-assessed skill ratings significantly improved after the course, and the appreciation of the course content was very positive. However, we observed a substantial drop-out rate, mostly attributed to the lack of time of medical professionals. There is a high demand for educational offerings regarding AI in medical imaging among medical professionals, and better education may lead to a more realistic appreciation of clinical adoption. However, time constraints imposed by a busy clinical schedule need to be taken into account for successful education of medical professionals.

Validated Multi-Physical Finite Element Modelling of the Spot Welding Process of the Advanced High Strength Steel DP1200HD.

Resistance spot welding (RSW) is a common joining technique in the production of car bodies in white for example, because of its high degree of automation, its short process time, and its reliability. While different steel grades and even dissimilar metals can be joined with this method, the current paper focuses on similar joints of galvanized advanced high strength steel (AHSS), namely dual phase steel with a yield strength of 1200 MPa and high ductility (DP1200HD). This material offers potential for light-weight design. The current work presents a multi-physical finite element (FE) model of the RSW process which gives insights into the local loading and material state, and which forms the basis for future investigations of the local risk of liquid metal assisted cracking and the effect of different process parameters on this risk. The model covers the evolution of the electrical, thermal, mechanical, and metallurgical fields during the complete spot welding process. Phase transformations like base material to austenite and further to steel melt during heating and all relevant transformations while cooling are considered. The model was fully parametrized based on lab scale material testing, accompanying model-based parameter determination, and literature data, and was validated against a large variety of optically inspected burst opened spot welds and micrographs of the welds.

Liquid Metal Embrittlement of Advanced High Strength Steel: Experiments and Damage Modeling.

In the automotive industry, corrosion protected galvanized advanced high strength steels with high ductility (AHSS-HD) gain importance due to their good formability and their lightweight potential. Unfortunately, under specific thermomechanical loading conditions such as during resistance spot welding galvanized, AHSS-HD sheets tend to show liquid metal embrittlement (LME). LME is an intergranular decohesion phenomenon leading to a drastic loss of ductility of up to 95%. The occurrence of LME for a given galvanized material mainly depends on thermal and mechanical loading. These influences are investigated for a dual phase steel with an ultimate tensile strength of 1200 MPa, a fracture strain of 14% and high ductility (DP1200HD) by means of systematic isothermal hot tensile testing on a Gleeble® 3800 thermomechanical simulator. Based on the experimental findings, a machine learning procedure using symbolic regression is applied to calibrate an LME damage model that accounts for the governing quantities of temperature, plastic strain and strain rate. The finite element (FE) implementation of the damage model is validated based on the local damage distribution in the hot tensile tested samples and in an exemplary 2-sheet resistance spot weld. The developed LME damage model predicts the local position and the local intensity of liquid metal induced cracking in both cases very well.

Microstructure and Local Mechanical Properties of the Heat-Affected Zone of a Resistance Spot Welded Medium-Mn Steel.

The properties of the heat-affected zone (HAZ) are reported to have a great influence on the mechanical performance of resistance spot welded advanced high strength steels. Therefore, in the present work, the HAZ of a medium-Mn steel is characterized regarding its microstructure and its mechanical properties depending on the distance to the fusion zone (FZ). In order to obtain the local mechanical properties of the HAZ, samples were heat-treated in a joule-heating thermal simulator using different peak temperatures to physically simulate the microstructure of the HAZ. By comparing the microstructure and the hardness of these heat-treated samples and the HAZ, the local peak temperatures within the HAZ could be determined. Subsequently, tensile tests were conducted, and the austenite phase fraction was measured magnetically on the physically simulated HAZ samples in order to determine the local mechanical properties of the HAZ. As verified by energy-dispersive X-ray spectroscopy, peak temperatures above 1200 °C led to a uniform distribution of manganese, resulting in a predominantly martensitic microstructure with high strength and low total elongation after quenching. Below 1100 °C, the diffusion of manganese is restricted, and considerable fractions of austenite remain stable. The austenite fraction increases almost linearly with decreasing peak temperature, which leads to an increase of the total elongation and to a slight decrease in the strength, depending on the distance to the FZ. Temperatures below 700 °C exhibit hardly any effect on the initial microstructure and mechanical properties.

Biological Regeneration of Articular Cartilage in an Early Stage of Compartmentalized Osteoarthritis: 12-Month Results.

BACKGROUND: Biological regeneration in an early stage of osteoarthritis (OA) is an important clinical challenge. An early-stage compartmentalized OA model was used to evaluate different biological regeneration techniques. HYPOTHESIS: Biological regeneration in an early stage of compartmentalized OA is possible. STUDY DESIGN: Controlled laboratory study. METHODS: A 7-mm cartilage defect was surgically created in 24 sheep. After 3 months, by which time early OA had set in, the sheep were randomized into 4 different treatment groups and operated for the second time. One group (CONTROL) served as a long-term follow-up group for the further development of OA. The other 3 groups (regeneration groups) each underwent a different regeneration procedure after abrasion of the subchondral bone (defect size: 20 × 10 mm with a depth of 2.5 mm): spongialization alone (SPONGIO), spongialization followed by implantation of an unseeded hyaluronan matrix (MATRIX), or spongialization followed by implantation of a hyaluronan matrix seeded with autologous chondrocytes (MACT). Then, 12 months after the second operative procedure, the animals were euthanized and the defects subjected to macroscopic and histological grading. Historical 4-month data were compared with the 12-month results. RESULTS: After 12 months of follow-up, advanced cartilage degeneration was observed in the CONTROL group. On the other hand, all regeneration groups improved significantly compared with the 4-month results using the Mankin score. Cartilage quality in the MACT group was significantly better than in the MATRIX group, as determined by the Mankin and the O'Driscoll scores. CONCLUSION: There are no existing clinical options for preventing early OA from progressing to a severe disease. This study provides important information on how a surgical intervention can forestall the development of OA. CLINICAL RELEVANCE: OA of the knee is very common. Total joint replacement is not an acceptable option for active patients. Biological regeneration in OA is successful for focal cartilage defects; however, a long-term follow-up for biological regeneration in OA is missing. It is essential to have long-term results for a regenerative procedure involving cartilage, which is a tissue with a very slow turnover.

Decoupling of Local Metabolic Activity and Functional Connectivity Links to Amyloid in Alzheimer's Disease.

BACKGROUND: Both ongoing local metabolic activity (LMA) and corresponding functional connectivity (FC) with remote brain regions are progressively impaired in Alzheimer's disease (AD), particularly in the posterior default mode network (pDMN); however, it is unknown how these impairments interact. It is well known that decreasing mean synaptic activity of a region, i.e., decreasing LMA, reduces the region's sensitivity to afferent input from other regions, i.e., FC. OBJECTIVE: We hypothesized progressive decoupling between LMA and FC in AD, which is linked to amyloid-ß pathology (Aß). METHODS: Healthy adults (n=20) and Aß+patients without memory impairment (n=9), early MCI (n=21), late MCI (n=18) and AD (n=22) were assessed by resting-state fMRI, FDG-PET, and AV-45-PET to measure FC, LMA, and Aß of the pDMN. Coupling between LMA and FC (rLA/FC) was estimated by voxelwise correlation. RESULTS: RLMA/FC decreased with disease severity (F=20.09, p<0.001). This decrease was specifically associated with pDMN Aß (r=-0.273, p=0.029) but not global Aß (r=-0.112, p=0.378) and with the impact of Aß on FC (i.e., rAß/FC,r=-0.339; p=0.006). In multiple regression models rLMA/FC was also associated with memory impairment, reduced cognitive speed and flexibility, outperforming global Aß, pDMN Aß, pDMN LMA, and pDMN FC, respectively. CONCLUSION: Results demonstrate increasing decoupling of LMA from its FC in AD. Data suggest that decoupling is driven by local Aß and contributes to memory decline.

Real-Time Monitoring of Psychotherapeutic Processes: Concept and Compliance.

OBJECTIVE: The feasibility of a high-frequency real-time monitoring approach to psychotherapy is outlined and tested for patients' compliance to evaluate its integration to everyday practice. Criteria concern the ecological momentary assessment, the assessment of therapy-related cognitions and emotions, equidistant time sampling, real-time nonlinear time series analysis, continuous participative process control by client and therapist, and the application of idiographic (person-specific) surveys. METHODS: The process-outcome monitoring is technically realized by an internet-based device for data collection and data analysis, the Synergetic Navigation System. Its feasibility is documented by a compliance study on 151 clients treated in an inpatient and a day-treatment clinic. RESULTS: We found high compliance rates (mean: 78.3%, median: 89.4%) amongst the respondents, independent of the severity of symptoms or the degree of impairment. Compared to other diagnoses, the compliance rate was lower in the group diagnosed with personality disorders. CONCLUSION: The results support the feasibility of high-frequency monitoring in routine psychotherapy settings. Daily collection of psychological surveys allows for the assessment of highly resolved, equidistant time series data which gives insight into the nonlinear qualities of therapeutic change processes (e.g., pattern transitions, critical instabilities).

The virus's tooth: cyanophages affect an African flamingo population in a bottom-up cascade.

Trophic cascade effects occur when a food web is disrupted by loss or significant reduction of one or more of its members. In East African Rift Valley lakes, the Lesser Flamingo is on top of a short food chain. At irregular intervals, the dominance of their most important food source, the cyanobacterium Arthrospira fusiformis, is interrupted. Bacteriophages are known as potentially controlling photoautotrophic bacterioplankton. In Lake Nakuru (Kenya), we found the highest abundance of suspended viruses ever recorded in a natural aquatic system. We document that cyanophage infection and the related breakdown of A. fusiformis biomass led to a dramatic reduction in flamingo abundance. This documents that virus infection at the very base of a food chain can affect, in a bottom-up cascade, the distribution of end consumers. We anticipate this as an important example for virus-mediated cascading effects, potentially occurring also in various other aquatic food webs.

Major and trace element geochemistry of Lake Bogoria and Lake Nakuru, Kenya, during extreme draught.

The physico-chemical properties of water samples from the two athalassic endorheic lakes Bogoria and Nakuru in Kenya were analysed. Surface water samples were taken between July 2008 and October 2009 in weekly intervals from each lake. The following parameters were determined: pH, salinity, electric conductivity, dissolved organic carbon (DOC), the major cations (FAAS and ICP-OES) and the major anions (IC), as well as certain trace elements (ICP-OES). Samples of superficial sediments were taken in October 2009 and examined using Instrumental Neutron Activation Analysis (INAA) for their major and trace element content including rare earth elements (REE). Both lakes are highly alkaline with a dominance of Na > K > Si > Ca in cations and HCO3 > CO3 > Cl > F > SO4 in anions. Both lakes also exhibited high concentrations of Mo, As and fluoride. Due to an extreme draught from March to October 2009, the water level of Lake Nakuru dropped significantly. This created drastic evapoconcentration, with the total salinity rising from about 20‰ up to 63‰. Most parameters (DOC, Na, K, Ca, F, Mo and As) increased with falling water levels. A clear change in the quality of DOC was observed, followed by an almost complete depletion of dissolved Fe from the water phase. In Lake Bogoria the evapoconcentration effects were less pronounced (total salinity changed from about 40‰ to 48‰). The distributions of REE in the superficial sediments of Lake Nakuru and Lake Bogoria are presented here for the first time. The results show a high abundance of the REE and a very distinct Eu depletion of Eu/Eu* = 0.33-0.45.

Critical-size defect induces unicompartmental osteoarthritis in a stable ovine knee.

Animal models simulating osteoarthritis are frequently associated with irreversible changes in biomechanics. Although these models successfully induce osteoarthritis, results of experimental repair procedures are impaired by biomechanical problems. The aim of this study was to define the critical size of a chondral lesion to induce unicompartmental osteoarthritis in a stable joint. Sixteen sheep were randomly divided into four treatment groups. A cartilage defect (7- or 14-mm diameter) was created in the weight-bearing zone of the medial femoral condyle. The sheep were mobilized for 6 or 12 weeks. Osteoarthritis was determined by gross assessment, India ink staining, histology (Mankin score), and analysis of COMP in the serum. In the 6-week group, only minor osteoarthritis was registered for either defect size. After 12 weeks, the 14-mm defect induced minor osteoarthritis at the femoral condyle and caused significant degenerative changes at the tibial articular cartilage and the meniscus. The 7-mm defect created focal unicompartmental osteoarthritis at the medial femoral condyle and minor degenerative changes at the corresponding tibia. A 7-mm full-thickness chondral defect with a weight-bearing regimen of 12 weeks induced local osteoarthritis at the medial compartment in an otherwise stable joint as aimed.

Subacute cutaneous lupus erythematosus and interstitial myositis occurring with hepatitis B infection: response to antiviral therapy with lamivudine.

Lupus erythematosus (LE) is a multisystem inflammatory disease resulting from an altered T- and B-cell response. Among various pathogenic factors, viral infections have been implicated in LE exacerbation. We describe a patient with acute onset of subacute cutaneous lupus erythematosus (SCLE) and interstitial myositis with mitochondrial changes in the context of an associated hepatitis B infection and the response of myositis to antiviral treatment with lamivudine. Viral vectors may play an important role in LE. A hitherto undescribed myositis with mitochondrial changes was associated with hepatitis B infection and SCLE and improved with antiviral treatment.

A comparison of two different treatments with navigated extracorporeal shock-wave therapy for calcifying tendinitis - a randomized controlled trial.

BACKGROUND: Extracorporeal shock-wave therapy is recommended for calcifying tendinitis, and navigated low-energy therapy has given better results than biofeedback localization. This investigation was planned to analyze whether the outcome of navigated low-energy shock-wave therapy can be improved by raising energy flux density to middle-energy levels. The clinical and radiological differences in outcome between three sessions of low-energy navigated shock-wave therapy and two sessions of middle-energy therapy were therefore compared. PATIENTS, MATERIALS AND METHODS: A prospective, randomized, observer-blind study was carried out in 50 patients whose mean age was 51 years. The population was randomized into two groups. Pain refractory to therapy was evident for more than six months in all patients. Radiographs and clinical examinations, including the Constant and Murley score, and the visual analog scale for pain assessment were performed before therapy and then after 12 weeks. Both groups of patients received navigated and X-ray-assisted, focused shock-wave treatment at weekly intervals. Group I underwent three sessions of constant low-energy treatment (0.08 mJ/mm(2); 1000 impulses) without local anesthesia; Group II received two middle-energy treatments (0.2 mJ/mm(2); 2000 impulses) with subacromial anesthesia. RESULTS: Forty-four patients (21 in Group I, 23 in Group II) completed the study protocol. Clinically, both groups improved significantly (P<0.0001) in the Constant and Murley score and the visual analog scale. The statistics within the groups were not significantly different. Overall, nine calcium deposits disappeared and 12 changed massively in shape and radiological density. CONCLUSIONS: Navigated shock-wave therapy significantly improves pain and shoulder function. Patients obtained nearly equal results after three low-energy or two middle-energy sessions of shock-wave treatment. We therefore recommend two sessions of middle-energy shock-wave therapy, as performed in Group II, because of the time-saving factor.

Cementless total hip arthroplasty with the rectangular titanium Zweymuller stem. A concise follow-up, at a minimum of fifteen years, of a previous report.

Between October 1986 and November 1987, 208 total hip arthroplasties were performed with use of the cementless Zweymüller stem and a threaded cup in 200 consecutive patients. Of 102 patients (108 hips) who were available for follow-up at a minimum of 180 months postoperatively, eighty-three (eighty-nine hips) had the primary joint replacement still intact. No stem had been revised because of aseptic loosening, but we found various degrees of osteolysis around sixteen (18%) of the implants. The probability of survival of the stem at fifteen years was 0.98 (95% confidence interval, 0.96 to 1.00). The probability of survival of the cup was 0.85 (95% confidence interval, 0.79 to 0.91).

Digital image enhancement for in vivo laser scanning microscopy.

BACKGROUND/PURPOSE: In vivo confocal laser scanning microscopy (CLSM) is a new method that provides skin images in horizontal plane at a level of resolution that allows to view microanatomic structures. This study examines whether certain digital image-processing steps can increase the visibility of various structures in CLSM. STUDY DESIGN: Fifty images were taken from normal skin of 25 probands, and 39 image enhancement procedures were created. Eight procedures that seemed to provide some quality enhancement were deliberately selected for further evaluation. Subsequently, a collection of random pairs of the original image and an image submitted to any of the eight selected procedures was rated by five independent observers. RESULTS: In three of the eight procedures tested, the modified image was significantly preferred to the original image (chi2-test,: P< or =0.001). In particular, smoothing, shading correction, delineate and grey-level normalization in various combinations were helpful in showing the characteristic honeycomb pattern, pigmented basal cell layer, cell borders and the nuclei more clearly. CONCLUSION: Digital image processing may help to increase visibility of in vivo CLSM images.

Cementless total hip arthroplasty with a tapered, rectangular titanium stem and a threaded cup: a minimum ten-year follow-up.

BACKGROUND: We report the results of cementless total hip arthroplasty with a tapered, rectangular titanium stem that was introduced in 1979 and continues to be used today with only minor changes. The aim of the design is to achieve primary stability to resist rotational and axial forces through precision rasping and press-fit implantation of a tapered, rectangular femoral component. METHODS: Between October 1986 and November 1987, 208 total hip arthroplasties with insertion of a tapered, rectangular titanium stem and a threaded cup without cement were performed in 200 consecutive patients (average age, sixty-one years; range, twenty-two to eighty-four years). RESULTS: At the time of the latest follow-up, fifty-one patients (fifty-two hips) had died and sixteen patients had been lost to follow-up, leaving 133 patients. Twelve hips had been revised, two in patients who subsequently died, leaving 123 living patients without revision. The median follow-up time was 120.7 months. Five cups needed revision surgery because of aseptic loosening; two, because of massive polyethylene wear; one, because of posttraumatic migration; and one, because of breakage. Three femoral stems were revised: one because of malpositioning (the reoperation was done five days after implantation); one, because of infection; and the third, after multiple failed acetabular revisions. The mean Harris hip score for the patients who did not have revision was 85.4 points (range, 46 to 100 points) at the time of the latest follow-up. Four patients (3%) complained of thigh pain that was not associated with another disorder. According to the criteria of Engh et al., all femoral implants were graded as stable bone-ingrown. The probability of survival of both the femoral and the acetabular component at ten years, with any revision as the end point, was 0.92 (95% confidence interval, 0.88 to 0.97). The probability of survival of the cup was 0.93 (95% confidence interval, 0.89 to 0.97), and that of the stem was 0.99 (95% confidence interval, 0.97 to 1.00). CONCLUSIONS: The results of arthroplasty with a tapered, rectangular titanium stem combined with a conical threaded cup inserted without cement were excellent at a minimum of ten years. Our data suggest that femoral stem fixation continues to be secure, while the threaded cup is prone to aseptic loosening.

Ultrasonography of the hip in the evaluation of children with seronegative juvenile rheumatoid arthritis.

OBJECTIVE: To find an objective measure of hip joint effusion with ultrasound (US) in patients with juvenile rheumatoid arthritis (JRA). METHODS: The hip joints of 24 children with JRA were evaluated with US. All patients were negative for rheumatoid factor and antinuclear antibodies. Patients with unilateral or bilateral hip pain, swelling, or limitation of range of motion were included. In each hip, the distance from the femoral neck to joint capsule was measured. Values were compared to measurements in a control group of 24 children with no history of hip joint or rheumatic disease. Statistically significant differences between the 2 groups were analyzed by t test. Two standard deviations above the control group mean was used as the standard for an effusion. RESULTS: There was a statistically significant difference in US joint space between the children with JRA and the control subjects (p < 0.001). The mean in the control group was 0.43 cm and the mean in the JRA group was 0.60 cm. A distance of 0.59 cm from femoral neck to joint capsule was determined to be consistent with an effusion. Using this standard, 71% of the children with JRA had effusion in at least one hip, and 25% had effusion bilaterally. No control subjects had measurements above this level. CONCLUSION: Ultrasonography is effective in the evaluation of hip joint involvement in patients with JRA, and may be useful in facilitating the diagnosis, classification, and followup of this illness.