Honeycomb micro-textures for light trapping in multi-crystalline silicon thin-film solar cells

The liquid phase crystallization (LPC) of silicon is an emerging technology for fabricating 10 - 20 µm thin multi-crystalline silicon layers on glass. LPC silicon solar cells exhibit similar electronic performance to multi-crystalline wafer-based devices. Due to the reduced absorber thickness, however, effective measures for light trapping have to be taken. We present tailor-made micro-structures for light trapping at the LPC silicon back-side, whereby a nano-imprinted resist layer serves as a three-dimensional etching mask in subsequent reactive ion etching. Contrary to state-of-the-art random pyramid textures produced by wet-chemical etching, this method allows to produce tailor-made textures independent of grain orientation. Differently shaped micro-textures were replicated in LPC silicon. Absorptance and external quantum efficiency of periodic honeycomb patterns and random pyramids were found to be equivalent. Thus, the method enables the potential to further optimize light trapping in LPC silicon solar cells.

Superselective Radioembolization of Hepatocellular Carcinoma: 5-Year Results of a Prospective Study

Twenty patients with unresectable hepatocellular carcinoma (HCC) were followed up to 5 years after transarterial radiotherapy with 90Y-resin particles. Diagnostic radioembolizations of 99mTc-macroaggregates facilitated scintigraphic assessment of activity distribution, dose evaluation and final procedural verification. The overall survival rates were 56, 38 and 14% (after 1, 2 and 3 years, resp.). Patients with unifocal HCC and a single feeding artery (n = 7) even presented 83, 67 and 40% (2 alive after 2.75 and 4 years). With multiple arteries (n = 7), the longest survival was 26 months. Patients with multifocal HCC survived up to 33 months after selective radioembolization. Quality of life was improved in all. Survival was positively correlated with absorbed dose but residual/recurrent tumour occurred even after ≥300 Gy. Post-treatment symptoms were minimal (35 applications), pulmonary shunt rates were correctly predicted and pulmonary complications avoided.

TGFβ-1 and epithelial-mesenchymal interactions promote smooth muscle gene expression in bone marrow stromal cells: Possible application in therapies for urological defects

Purpose

For regenerative and cellular therapies of the urinary tract system, autologous bladder smooth muscle cells (SMCs) have several limitations, including constricted in vitro proliferation capacity and, more importantly, inability to be used in malignant conditions. The use of in vitro (pre-)differentiated multipotential adult progenitor cells may help to overcome the shortcomings associated with primary cells.

Methods

By mimicking environmental conditions of the bladder wall, we investigated in vitro effects of growth factor applications and epithelial-mesenchymal interactions on smooth muscle gene expression and on the morphological appearance of adherent bone marrow stromal cells (BMSCs).

Results

Transcription growth factor beta-1 (TGFβ-1) upregulated the transcription of myogenic gene desmin and smooth muscle actin-γ2 in cultured BMSCs. Stimulatory effects were significantly increased by coculture with urothelial cells. Prolonged stimulation times and epigenetic modifications further enhanced transcription levels, indicating a dose-response relationship. Immunocytochemical staining of in vitro-differentiated BMSCs revealed expression of myogenic protein α-smooth muscle actin and desmin, and changes in morphological appearance from a fusiform convex shape to a laminar flattened shape with filamentous inclusions similar to the appearance of bladder SMCs. In contrast to the TGFβ-1 action, application of vascular endothelial growth factor (VEGF) did not affect the cells.

Conclusions

The combined application of TGFβ-1 and epithelial-mesenchymal interactions promoted in vitro outgrowth of cells with a smooth muscle-like phenotype from a selected adherent murine bone marrow-derived cell population.

“UroMaix” Scaffolds: Novel Collagen Matrices for Application in Tissue Engineering of the Urinary Tract

Reconstruction of bladder and ureter tissue is indicated in cases of injury, stenosis, infection or tumor. Substitution by ileum, colon or pure synthetic polymers generates a variety of complications. Biohybrid tissue mimicking structural and functional attributes of the multilayered wall architecture of the urinary conduit may be the solution to current problems.

This study reports on porcine urinary tract cells isolated and placed on UroMaix matrices with different degrees of cross-linking produced from highly purified type I collagen from medically approved porcine tissue. A patented procedure revealed membrane structures composed of a dense fibrous side and an open fibrous side. These scaffolds with the porcine urinary tract cells were incubated in a batch culture system for up to 14 days. Cell growth and topographical orientation were examined.

Urothelial cells showed maximum attachment and a significant increase of living cells on the dense fiber layer of UroMaix-1. No attachment of urothelial cells occurred on the other prototypes. Smooth muscle cells showed similar behavior within the open fiber layer of all UroMaix matrices. Both urothelial and smooth muscle cells retained their phenotypes as demonstrated by the immunostaining of epithelial cytokeratin 18 and the smooth muscle myosin heavy chain respectively. Thus we could show that UroMaix scaffolds support the attachment and proliferation of urinary tract cells. The elastomeric properties of the collagenous matrices promise attractive applications in the tissue engineering of the urinary tract with its high mechanical demands.

Engrafting Periodontal Fibroblasts with New 3-Dimensional Polylactide Foams

In clinical periodontics, “tissue engineering” techniques have been developed to guide the regenerative process following periodontal disease. We explored a new shaped biomaterial in order to promote cellular adhesion, proliferation and migration of periodontal cells. Granules of poly-D,L-lactide were foamed in specially designed moulds by a controlled gas-loading process. Explant cultures of periodontal tissue were seeded at different densities on the 3-dimensional scaffolds following analysis of cytotoxicity, cell proliferation and differentiation. The moulding procedure led to porous structures with predetermined tubes for cellular locomotion. Cells adhered to and populated the material's surface and inner cavities while retaining fibroblastic phenotype. An optimal ratio between cellular proliferation and mortality rate was achieved at a seeding density of > 106 cells/cm3 scaffold. We designed modified polylactide scaffolds capable of acting as a stent and a cell carrier matrix. The foaming process is easy, cheap and suitable for commercial production.

Restaging of patients with lymphoma

Aim: Assessment of the clinical benefit of i.v. contrast enhanced diagnostic CT (CE-CT) compared to low dose CT with 20 mAs (LD-CT) without contrast medium in combined [18F]-FDG PET/CT examinations in restaging of patients with lymphoma. Patients, methods: 45 patients with non-Hodgkin lymphoma (n = 35) and Hodgkin's disease (n = 10) were included into this study. PET, LD-CT and CECT were analyzed separately as well as side-by-side. Lymphoma involvement was evaluated separately for seven regions. Indeterminate diagnoses were accepted whenever there was a discrepancy between PET and CT findings. Results for combined reading were calculated by rating indeterminate diagnoses according the suggestions of either CT or PET. Each patient had a clinical follow-up evaluation for >6 months. Results: Region-based evaluation suggested a sensitivity/specificity of 66/93% for LD-CT, 87%/91% for CE-CT, 95%/96% for PET, 94%/99% for PET/LD-CT and 96%/99% for PET/CE-CT. The data for PET/CT were obtained by rating indeterminate results according to the suggestions of PET, which turned out to be superior to CT. Lymphoma staging was changed in two patients using PET/ CE-CT as compared to PET/LD-CT. Conclusion: Overall, there was no significant difference between PET/LD-CT and PET/CE-CT. However, PET/CE-CT yielded a more precise lesion delineation than PET/LD-CT. This was due to the improved image quality of CE-CT and might lead to a more accurate investigation of lymphoma.

Nrf2-dependent persistent oxidative stress results in stress-induced vulnerability to depression

Stressful life events produce a state of vulnerability to depression in some individuals. The mechanisms that contribute to vulnerability to depression remain poorly understood. A rat model of intense stress (social defeat (SD), first hit) produced vulnerability to depression in 40% of animals. Only vulnerable animals developed a depression-like phenotype after a second stressful hit (chronic mild stress). We found that this vulnerability to depression resulted from a persistent state of oxidative stress, which was reversed by treatment with antioxidants. This persistent state of oxidative stress was due to low brain-derived neurotrophic factor (BDNF) levels, which characterized the vulnerable animals. We found that BDNF constitutively controlled the nuclear translocation of the master redox-sensitive transcription factor Nrf2, which activates antioxidant defenses. Low BDNF levels in vulnerable animals prevented Nrf2 translocation and consequently prevented the activation of detoxifying/antioxidant enzymes, ultimately resulting in the generation of sustained oxidative stress. Activating Nrf2 translocation restored redox homeostasis and reversed vulnerability to depression. This mechanism was confirmed in Nrf2-null mice. The mice displayed high levels of oxidative stress and were inherently vulnerable to depression, but this phenotype was reversed by treatment with antioxidants. Our data reveal a novel role for BDNF in controlling redox homeostasis and provide a mechanistic explanation for post-stress vulnerability to depression while suggesting ways to reverse it. Because numerous enzymatic reactions produce reactive oxygen species that must then be cleared, the finding that BDNF controls endogenous redox homeostasis opens new avenues for investigation.

High Intensity Functional Exercise (HIFE) Training

Hintergrund: Das in Schweden entwickelte und evaluierte Trainingsprogramm „High Intensity Functional Exercise“ (HIFE) wird dort zur Sturzprävention im stationären Seniorenpflegebereich eingesetzt. Das Programm besteht aus funktionellen, hochintensiven Kraft- und Balanceübungen und könnte eine wertvolle Ergänzung zu bereits bestehenden Sturzpräventionsprogrammen in Deutschland darstellen.

Ziel: Überprüfung der Anwendbarkeit des HIFE-Programms in 2 deutschen Pflegeheimen.

Methode: Machbarkeitsstudie einer 10-wöchigen HIFE-Intervention mit 16 Teilnehmern*. Primäre Zielparameter waren Teilnahme- und Drop-out-Raten, Beschwerden und Nebenwirkungen, Akzeptanz bei Heimleitung und Pflegepersonal. Sekundäre Zielparameter umfassten 30-Seconds Chair Rising Test (30 CR), 5-Seconds Chair Rising Test (5 CR), habituelle und maximale Gehgeschwindigkeit, Timed Up and Go Test (TUG), Sit and Reach Test (SR) und Standbalance zur Beschreibung funktioneller Veränderungen im Prä-Post-Vergleich.

Ergebnisse: Während der Intervention traten keine schwerwiegenden Nebenwirkungen auf. Teilnahmeraten und Akzeptanz des HIFE-Programms waren bei Heimleitung und Pflegepersonal sehr gut und die Drop-out-Rate gering. Die Standbalance (p < 0,05), funktionelle Beinkraft (30 CR: p < 0,005, 5 CR: p < 0,005) und habituelle Gehgeschwindigkeit (p < 0,05) verbesserten sich signifikant. Die Verbesserungen der maximalen Gehgeschwindigkeit (p = 0,075) und im TUG (p = 0,05) erreichten kein signifikantes Niveau. Die Beweglichkeit beim SR veränderte sich nicht (p = 0,608).

Schlussfolgerungen: Das HIFE-Trainingsprogramm lässt sich ist in Deutschland sicher und praktikabel anwenden. Verbesserungen funktioneller Parameter sind zu erwarten, was insgesamt einen wertvollen Beitrag zur Sturzprävention in Seniorenheimen leisten kann.

[Splice variant AR-V7 : Is it time for its routine use as a predictive marker in prostate cancer?]

Androgen receptor splice variants (AR-Vs), if overexpressed, lack the ligand-binding domain conveying metastasized castration-resistant prostate cancer with a therapeutic resistance to androgen receptor signaling inhibitors. Particularly AR-V7 has recently been proposed as a potential predictive biomarker to identify patients who would probably benefit most from taxane-based cytotoxic treatment. Several assays to substantiate or quantify AR-V7 expression have recently been proposed. However, their broad clinical value is still debatable. This contemporary update aims to shed light on the current evidence in the field and draw distinct practical conclusions.

Primary lower limb lymphoedema: classification with non-contrast MR lymphography

PURPOSE

The purpose of the present study was to analyse the performance of non-contrast MR lymphography for the classification of primary lower limb lymphoedema in 121 consecutive patients with 187 primary lower limb lymphoedemas.

MATERIALS AND METHODS

121 consecutive patients with clinically diagnosed primary lower limb lymphoedema underwent non-contrast MR lymphography with a free-breathing 3D fast spin-echo sequence with a very long TR/TE (4000/884 ms). MR examinations were retrospectively reviewed for severity of lymphoedema (absent, mild, moderate, severe) and characteristics of inguinal lymph nodes and iliac and inguinal lymphatic trunks graded as aplasic (no lymph nodes or lymphatic trunks), hypoplasic (less lymph nodes or lymphatic trunks), normal and hyperplasic (more lymph nodes or more and/or dilated trunks).

RESULTS

There was an excellent correlation between clinical stage and severity of lymphoedema (Cramer's V of 0,73 (p < 0.001)). Differentiation was feasible between inguinal lymphatic vessel aplasia (21%), hypoplasia (15%), normal pattern (53%) and hyperplasia (11%). Severe lymphoedema was observed in 46% of aplasic patterns and in 37% of hyperplasic patterns, but in only 15% of hypoplasic patterns and never observed in normal patterns (p < 0.001).

CONCLUSION

Non-contrast MR lymphography is able to classify primary lower limb lymphoedemas into hyperplasic, aplasic, hypoplasic and normal patterns.

KEY POINTS

• Non-contrast MR lymphography is able to classify primary lower limb lymphoedemas. • Lymphoedema can be classified in hyperplasic, aplasic, hypoplasic and normal patterns. • Non-contrast MR lymphography can optimize clinical management of primary lower limb lymphoedemas.

Investigation of Feshbach resonances in ultracold 40K spin mixtures

Magnetically tunable Feshbach resonances are an indispensable tool for experiments with atomic quantum gases. We report on 37 thus far unpublished Feshbach resonances and four further probable Feshbach resonances in spin mixtures of ultracold fermionic ⁴⁰K with temperatures well below 100 nK. In particular, we locate a broad resonance at B = 389.7G with a magnetic width of 26.7 G. Here 1 G = 10^-4 T. Furthermore, by exciting low-energy spin waves, we demonstrate a means to precisely determine the zero crossing of the scattering length for this broad Feshbach resonance. Our findings allow for further tunability in experiments with ultracold ⁴⁰K quantum gases.

A millikelvin all-fiber cavity optomechanical apparatus for merging with ultra-cold atoms in a hybrid quantum system

We describe the construction of an apparatus designed to realize a hybrid quantum system comprised of a cryogenically cooled mechanical oscillator and ultra-cold ⁸⁷Rb atoms coupled via light. The outstanding feature of our instrument is an in situ adjustable asymmetric all-fiber membrane-in-the-middle cavity located inside an ultra-high vacuum dilution refrigerator based cryostat. We show that Bose-Einstein condensates of N=2×10⁶ atoms can be produced in less than 20 s and demonstrate a single photon optomechanical coupling strength of g₀=2π×9 kHz employing a high-stress Si₃N₄ membrane with a mechanical quality factor Q_m>10⁷ at a cavity setup temperature of T_MiM = 480 mK.

Fracture risk in people with developmental disabilities: results of a large claims data analysis

Age- and sex-specific fracture rates of 18,000 people with developmental disabilities aged 0-69 years were compared to the general population. Age-standardized incidence of femoral fracture was 4.8- and 7.1-fold higher in women and men, respectively. Comparable fracture risks to the general population occurred 10-15 years earlier in females and 20-40 years earlier in males.

INTRODUCTION

Previous studies suggested that fracture risks in people with developmental disabilities (DD) may be higher than in people in the general population. However, there are no current sufficiently large studies to compare age- and sex-specific fracture rates of single fracture types.

METHODS

People with DD and incident fractures were identified by routine data of a health insurance company. Fractures in the general population were derived from the official fracture statistics. Age-specific and age-standardized fracture incidences were analyzed. To compare fracture risks in people with DD with that of the general population incidence ratios were calculated.

RESULTS

Between 2008 and 2010, 148 femoral fractures and 469 other fractures were observed in nearly 18,000 people with DD aged 0-69 years. The three most frequent fracture types leading to hospital admission were fractures of the femur, lower leg/ankle, and shoulder/arm. For femoral fractures, a particularly high risk was observed in children and adolescents with DD. In adults with DD, the risk of femoral fractures increased with increasing age. Even if the youngest age category was not considered, the age-standardized incidence was 4.8- and 7.1-fold higher in women and men, respectively. For all other fracture types, except fractures of forearm/hand and of pelvis, people with DD had also higher fracture incidences than the general population.

CONCLUSIONS

People with DD have a high fracture burden. Comparable risks of femoral fracture, for example, occurred about 10-15 years earlier in females and even 20-40 years earlier in males with DD than in the general population.

Nrf2-dependent persistent oxidative stress results in stress-induced vulnerability to depression

This corrects the article DOI: 10.1038/mp.2016.144.