Inverted Perovskite Photovoltaics Using Flame Spray Pyrolysis Solution Based CuAlO2/Cu−O Hole-Selective Contact

We present the functionalization process of a conductive and transparent CuAlO2/Cu-O hole-transporting layer (HTL). The CuAlO2/Cu-O powders were developed by flame spray pyrolysis and their stabilized dispersions were treated by sonication and centrifugation methods. We show that when the supernatant part of the treated CuAlO2/Cu-O dispersions is used for the development of CuAlO2/Cu-O HTLs the corresponding inverted perovskite-based solar cells show improved functionality and power conversion efficiency of up to 16.3% with negligible hysteresis effect

Biocompatibility and Bone Formation of Flexible, Cotton Wool-like PLGA/Calcium Phosphate Nanocomposites in Sheep

BACKGROUND: The purpose of this preliminary study was to assess the in vivo performance of synthetic, cotton wool-like nanocomposites consisting of a biodegradable poly(lactide-co-glycolide) fibrous matrix and containing either calcium phosphate nanoparticles (PLGA/CaP 60:40) or silver doped CaP nanoparticles (PLGA/Ag-CaP 60:40). Besides its extraordinary in vitro bioactivity the latter biomaterial (0.4 wt% total silver concentration) provides additional antimicrobial properties for treating bone defects exposed to microorganisms. MATERIALS AND METHODS: Both flexible artificial bone substitutes were implanted into totally 16 epiphyseal and metaphyseal drill hole defects of long bone in sheep and followed for 8 weeks. Histological and histomorphological analyses were conducted to evaluate the biocompatibility and bone formation applying a score system. The influence of silver on the in vivo performance was further investigated. RESULTS: Semi-quantitative evaluation of histology sections showed for both implant materials an excellent biocompatibility and bone healing with no resorption in the adjacent bone. No signs of inflammation were detectable, either macroscopically or microscopically, as was evident in 5 µm plastic sections by the minimal amount of inflammatory cells. The fibrous biomaterials enabled bone formation directly in the centre of the former defect. The area fraction of new bone formation as determined histomorphometrically after 8 weeks implantation was very similar with 20.5 ± 11.2 % and 22.5 ± 9.2 % for PLGA/CaP and PLGA/Ag-CaP, respectively. CONCLUSIONS: The cotton wool-like bone substitute material is easily applicable, biocompatible and might be beneficial in minimal invasive surgery for treating bone defects

Active rehabilitation for chronic low back pain: Cognitive-behavioral, physical, or both? First direct post-treatment results from a randomized controlled trial [ISRCTN22714229]

BACKGROUND: The treatment of non-specific chronic low back pain is often based on three different models regarding the development and maintenance of pain and especially functional limitations: the deconditioning model, the cognitive behavioral model and the biopsychosocial model. There is evidence that rehabilitation of patients with chronic low back pain is more effective than no treatment, but information is lacking about the differential effectiveness of different kinds of rehabilitation. A direct comparison of a physical, a cognitive-behavioral treatment and a combination of both has never been carried out so far. METHODS: The effectiveness of active physical, cognitive-behavioral and combined treatment for chronic non-specific low back pain compared with a waiting list control group was determined by performing a randomized controlled trial in three rehabilitation centers. Two hundred and twenty three patients were randomized, using concealed block randomization to one of the following treatments, which they attended three times a week for 10 weeks: Active Physical Treatment (APT), Cognitive-Behavioral Treatment (CBT), Combined Treatment of APT and CBT (CT), or Waiting List (WL). The outcome variables were self-reported functional limitations, patient's main complaints, pain, mood, self-rated treatment effectiveness, treatment satisfaction and physical performance including walking, standing up, reaching forward, stair climbing and lifting. Assessments were carried out by blinded research assistants at baseline and immediately post-treatment. The data were analyzed using the intention-to-treat principle. RESULTS: For 212 patients, data were available for analysis. After treatment, significant reductions were observed in functional limitations, patient's main complaints and pain intensity for all three active treatments compared to the WL. Also, the self-rated treatment effectiveness and satisfaction appeared to be higher in the three active treatments. Several physical performance tasks improved in APT and CT but not in CBT. No clinically relevant differences were found between the CT and APT, or between CT and CBT. CONCLUSION: All three active treatments were effective in comparison to no treatment, but no clinically relevant differences between the combined and the single component treatments were found

Ebola virus disease in West Africa — the first 9 Months of the epidemic and forward projections

BACKGROUND On March 23, 2014, the World Health Organization (WHO) was notified of an outbreak of Ebola virus disease (EVD) in Guinea. On August 8, the WHO declared the epidemic to be a "public health emergency of international concern." METHODS By September 14, 2014, a total of 4507 probable and confirmed cases, including 2296 deaths from EVD (Zaire species) had been reported from five countries in West Africa - Guinea, Liberia, Nigeria, Senegal, and Sierra Leone. We analyzed a detailed subset of data on 3343 confirmed and 667 probable Ebola cases collected in Guinea, Liberia, Nigeria, and Sierra Leone as of September 14. RESULTS The majority of patients are 15 to 44 years of age (49.9% male), and we estimate that the case fatality rate is 70.8% (95% confidence interval [CI], 69 to 73) among persons with known clinical outcome of infection. The course of infection, including signs and symptoms, incubation period (11.4 days), and serial interval (15.3 days), is similar to that reported in previous outbreaks of EVD. On the basis of the initial periods of exponential growth, the estimated basic reproduction numbers (R-0) are 1.71 (95% CI, 1.44 to 2.01) for Guinea, 1.83 (95% CI, 1.72 to 1.94) for Liberia, and 2.02 (95% CI, 1.79 to 2.26) for Sierra Leone. The estimated current reproduction numbers (R) are 1.81 (95% CI, 1.60 to 2.03) for Guinea, 1.51 (95% CI, 1.41 to 1.60) for Liberia, and 1.38 (95% CI, 1.27 to 1.51) for Sierra Leone; the corresponding doubling times are 15.7 days (95% CI, 12.9 to 20.3) for Guinea, 23.6 days (95% CI, 20.2 to 28.2) for Liberia, and 30.2 days (95% CI, 23.6 to 42.3) for Sierra Leone. Assuming no change in the control measures for this epidemic, by November 2, 2014, the cumulative reported numbers of confirmed and probable cases are predicted to be 5740 in Guinea, 9890 in Liberia, and 5000 in Sierra Leone, exceeding 20,000 in total. CONCLUSIONS These data indicate that without drastic improvements in control measures, the numbers of cases of and deaths from EVD are expected to continue increasing from hundreds to thousands per week in the coming months

The first 100 patients treated with a new anatomical pre-contoured locking plate for clavicular midshaft fractures

Abstract Background Pre-contoured locking plates were recently introduced in the management of clavicular midshaft fractures. These plates may offer advantages such as no necessity for intraoperative bending and reduced plate irritation. The purpose of this study was to review the clinical and radiographical outcome of the first 100 patients treated with a new anatomical pre-contoured locking plate. Methods In a retrospective single-center study, 100 consecutive patients (16 female, 84 male) with a median age of 40 years (range 15–82) who underwent surgery for clavicular midshaft fractures with a VariAx locking plate (Stryker Corporation Kalmazoo, MI, USA) between March 2012 and January 2016 were included. Postoperative follow-up was performed until union was clinically and radiographically achieved. Fracture type, surgical time, intraoperative need for contouring the plate, further surgery such as revision or hardware removal and complications were recorded. Results One-hundred patients with a dislocated midshaft clavicular fracture with a mean follow-up of 21.9 months (standard deviation 13.2) were included. Ninety-three patients reported normal shoulder function at latest follow-up. Median surgical time was 75.5 min (range, 35–179). In three patients, intraoperative bending of the plate was necessary. In two patients, plates designed for the other side were implanted. Five patients needed revision surgery: One patient with wound healing problems, one patient with a re-fracture after early (13 months) hardware removal and minor trauma, one patient with postoperative shoulder stiffness and two patients with failed osteosynthesis because of surgical implantation fault. One asymptomatic nonunion without further treatment was observed. In 30 patients, the plate was removed after a mean of 17.5 months (SD 4.2) because of subjective plate discomfort. Conclusions With this new pre-contoured locking plate, good to excellent intraoperative fit to the anatomical shape of the clavicle can be achieved. The implant seems to be reliable regarding handling and complications. Clinical and radiological results are comparable to results reported in the literature. Hardware removal rate is comparable to other studies with a pre-contoured plate and lower compared to non-pre-contoured

Nanocomposites of high-density polyethylene with amorphous calcium phosphate: in vitro biomineralization and cytocompatibility of human mesenchymal stem cells

Polyethylene is widely used as a component of implants in medicine. Composites made of high-density polyethylene (HDPE) containing different amounts of amorphous calcium phosphate nanoparticles were investigated concerning their in vitro biomedical performance. The nanoparticles were produced by flame spray synthesis and extruded with HDPE, the latter complying with Food and Drug Administration regulations. Mechanical properties such as Young's modulus and contact angle as well as in vitro biomineralization of the nanocomposites hot-pressed into thin films were evaluated. The deposition of a hydroxyapatite layer occurred upon immersion in simulated body fluid. Additionally, a cell culture study with human mesenchymal stem cells for six weeks allowed a primary assessment of the cytocompatibility. Viability assays (alamarBlue and lactate dehydrogenase detection) proved the absence of cytotoxic effects of the scaffolds. Microscopic images after hematoxylin and eosin staining confirmed typical growth and morphology. A preliminary experiment analyzed the alkaline phosphatase activity after two weeks. These findings motivate further investigations on bioactive HDPE in bone tissue engineering

Pressureless Mechanical Induction of Stem Cell Differentiation Is Dose and Frequency Dependent

<div><p>Movement is a key characteristic of higher organisms. During mammalian embryogenesis fetal movements have been found critical to normal tissue development. On the single cell level, however, our current understanding of stem cell differentiation concentrates on inducing factors through cytokine mediated biochemical signaling. In this study, human mesenchymal stem cells and chondrogenesis were investigated as representative examples. We show that pressureless, soft mechanical stimulation precipitated by the cyclic deformation of soft, magnetic hydrogel scaffolds with an external magnetic field, can induce chondrogenesis in mesenchymal stem cells without any additional chondrogenesis transcription factors (TGF-β1 and dexamethasone). A systematic study on the role of movement frequency revealed a classical dose-response relationship for human mesenchymal stem cells differentiation towards cartilage using mere mechanical stimulation. This effect could even be synergistically amplified when exogenous chondrogenic factors and movement were combined.</p> </div

Frequency dependent hMSC differentiation.

<p>Mechanical stimulation frequency influences the differentiation and formation of tissue-typical extracellular matrix (amount of GAG formed) in both control and chondrogenic medium. Cells were pressure-free stretched on soft scaffolds for 2 seconds (stimulation period). Non-moved scaffolds (left) served as additional controls. The amount of GAG deposition indicated differentiation on all mechanical stimulated scaffolds particularly at high frequency. This behavior shows that mechanical soft movement follows a dose-effect type response similar to a classical response of specific cells to a given biochemical factor.</p

Chondrogenesis on magnetic hydrogels with and without mechanical stimulation.

<p>Aggrecan (antibody labeling, red), SOX9 (antibody labeling, green) and Collagen II expression (green) immunohistochemistry of hMSC over a period of 5 weeks. Cell cultures were either not stimulated or underwent repeated mechanical stimulation (left). The role of movement was investigated both in control medium (top rows) and in standard chondrogenic medium (bottom rows). Samples were counterstained with DAPI to make cell nuclei visible. Mechanical stimulation resulted in clear up-regulation of all chondrogenic markers if compared to the non-stimulated control cultures.</p