Gain in Three-Dimensional Metamaterials utilizing Semiconductor Quantum Structures

We demonstrate gain in a three-dimensional metal/semiconductor metamaterial by the integration of optically active semiconductor quantum structures. The rolling-up of a metallic structure on top of strained semiconductor layers containing a quantum well allows us to achieve a three-dimensional superlattice consisting of alternating layers of lossy metallic and amplifying gain material. We show that the transmission through the superlattice can be enhanced by exciting the quantum well optically under both pulsed or continuous wave excitation. This points out that our structures can be used as a starting point for arbitrary three-dimensional metamaterials including gain

Conjugated oligomers with alternating heterocycles from a single monomer:synthesis and demonstration of electroluminescence

International audienceConjugated oligomers based on two different heterocycles are typically prepared by step growth polycondensation cross-coupling methods from two monomers X-Cycle1-X and M-Cycle2-M with no control of the regioselectivity. In this work, we used a new synthetic strategy that involves an extremely chemoselective reaction of a dielectrophilic compound, X1 Cycle1 X2, with a dinucleophilic component, M1-Cycle2-M2, under Stille conditions. The resulting monomers, X1 Cycle1 Cycle2-M2 are di-heterocyclic push pull monomers that still contain a nucleophilic site (boronic acid) and electrophilic site (bromide) and are set up for a controlled polymerization under Suzuki conditions. In this way, two semiconducting oligomers, based on thiophene / benzene and thiophene / pyridine motifs were synthesized. Both oligomers were characterized in terms of their, thermal, electrochemical, absorption, emission and electroluminescence properties

Leukoencephalopathy after prophylactic whole-brain irradiation with or without hippocampal sparing: a longitudinal magnetic resonance imaging analysis

PURPOSE Neurocognitive changes are well described after prophylactic or therapeutic whole-brain radiotherapy (WBRT) and have been reported as early as 3 months after radiotherapy (RT). Therefore, WBRT with protection of the hippocampal region (hippocampal avoidance, HA) has been proposed to preserve neurocognition. Our aim was to compare the risk of leukoencephalopathy after prophylactic cranial irradiation (PCI) with or without HA. METHODS Patients with small-cell lung cancer who received either lateral-opposed field PCI (non-HA-PCI; n = 9) or hippocampus avoidance PCI (HA-PCI; n = 9) with available magnetic resonance imaging (MRI) follow-up were identified and age matched. Pre-therapeutic and follow-up MRI after RT was analysed for leukoencephalopathy based on the Fazekas score. Bilateral cortical and subcortical brain structures were segmented and analysed for alterations in dosimetric parameters and volumes. RESULTS There was no significant difference of Fazekas scores between groups at baseline. Fazekas score differed in post-treatment with a median of 1 in the HA-PCI group and 2 in the non-HA-PCI group (p = 0.007). Significant increase of Fazekas score over time after RT was observed for HA-PCI patients (p = 0.001) but not for non-HA-PCI patients. Dmax (highest radiation dose) and brain volume receiving doses >25Gy were higher in HA-PCI patients. There were no significant volumetric differences for segmented brain structures between groups. CONCLUSION Radiological changes are more prominent after HA-PCI than after non-HA-PCI. Although no standardised neurocognitive testing was performed, the significantly increased Fazekas scores after HA-PCI are expected to interfere with neurocognitive function. Prospective long-term neurocognitive studies are warranted before HA-PCI is implemented in routine clinical practice

Pilonidal Sinus Recurrence Rates in Young Adults—Similar to Children or Adults?

Background/Objectives: Treatment strategies in pilonidal sinus disease differ substantially between adults and children. While a single surgery with off-midline flap closure is recommended for adults, minimally invasive procedures are preferred in children due to their much higher recurrence rates. Recently, this strategy has been extended to young adults, but long-term recurrence rates in this age group are unknown. Methods: An established database of studies on pilonidal sinus disease was used for the present study. All entries providing information on age and recurrence over time were included. We compared recurrence rates between children (21 years) using Kaplan–Meier curves. Between-groups testing employed the two-tailed log rank test. Results: We included 856 entries with 88,348 patients, of which 5635 were children and 3999 young adults. The 5-year recurrence rate in children was 45.1% (95% confidence interval: 40.2–49.7%). For older adults it was 11.5% (95% confidence interval: 11.1–11.8%) and 8.7% (95% confidence interval: 7.4–10%) in young adults. The recurrence rate in young adults was lower than in children (log rank p < 0.001) and comparable, albeit slightly lower, to older adults (log rank p < 0.001). Conclusions: Our results indicate that recurrence rates between young and older adults are similar. Consequently, treatment strategies for young adults could follow the recommendations for adults instead of those for children. Due to the limited quality of available evidence, this requires validation in primary studies with sufficiently long follow-up.This research received no external funding

Overall complication rates of DIEP flap breast reconstructions in Germany – a multi-center analysis based on the DGPRÄC prospective national online registry for microsurgical breast reconstructions

While autologous breast reconstruction has gained momentum over recent years, there is limited data on the structure and quality of care of microsurgical breast reconstruction in Germany. Using the breast reconstruction database established by the German Society of Plastic, Reconstructive and Aesthetic Surgeons (DGPRÄC), the presented study investigated the overall outcomes of deep inferior epigastric perforator (DIEP) flap reconstructions in Germany. Data of 3926 patients and 4577 DIEP flaps performed by 22 centers were included in this study. Demographics, patient characteristics, perioperative details and postoperative outcomes were accounted for. Centers performing < Ø 40 (low-volume (LV)) vs. ≥ Ø 40 (high-volume (HV)) annual DIEP flaps were analyzed separately. Overall, total and partial flap loss rates were as low as 2.0% and 1.1% respectively, and emergent vascular revision surgery was performed in 4.3% of cases. Revision surgery due to wound complications was conducted in 8.3% of all cases. Mean operative time and length of hospital stay was significantly shorter in the HV group (LV: 385.82 min vs. HV: 287.14 min; LV: 9.04 (18.87) days vs. HV: 8.21 (5.04) days; both p < 0.05). The outcome and complication rates deduced from the national registry underline the high standard of microsurgical breast reconstruction on a national level in Germany

Epidemic Microclusters of Blood-Culture Proven Sepsis in Very-Low-Birth Weight Infants: Experience of the German Neonatal Network

INTRODUCTION: We evaluated blood culture-proven sepsis episodes occurring in microclusters in very-low-birth-weight infants born in the German Neonatal Network (GNN) during 2009-2010. METHODS: Thirty-seven centers participated in GNN; 23 centers enrolled ≥50 VLBW infants in the study period. Data quality was approved by on-site monitoring. Microclusters of sepsis were defined as occurrence of at least two blood-culture proven sepsis events in different patients of one center within 3 months with the same bacterial species. For microcluster analysis, we selected sepsis episodes with typically cross-transmitted bacteria of high clinical significance including gram-negative rods and Enterococcus spp. RESULTS: In our cohort, 12/2110 (0.6%) infants were documented with an early-onset sepsis and 235 late-onset sepsis episodes (≥72 h of age) occurred in 203/2110 (9.6%) VLBW infants. In 182/235 (77.4%) late-onset sepsis episodes gram-positive bacteria were documented, while coagulase negative staphylococci were found to be the most predominant pathogens (48.5%, 95%CI: 42.01-55.01). Candida spp. and gram-negative bacilli caused 10/235 (4.3%, 95%CI: 1.68% -6.83%) and 43/235 (18.5%) late-onset sepsis episodes, respectively. Eleven microclusters of blood-culture proven sepsis were detected in 7 hospitals involving a total 26 infants. 16/26 cluster patients suffered from Klebsiella spp. sepsis. The median time interval between the first patient's Klebsiella spp. sepsis and cluster cases was 14.1 days (interquartile range: 1-27 days). First patients in the cluster, their linked cases and sporadic sepsis events did not show significant differences in short term outcome parameters. DISCUSSION: Microclusters of infection are an important phenomenon for late-onset sepsis. Most gram-negative cluster infections occur within 30 days after the first patient was diagnosed and Klebsiella spp. play a major role. It is essential to monitor epidemic microclusters of sepsis in surveillance networks to adapt clinical practice, inform policy and further improve quality of care

Steering customers to the online channel: The influence of personal relationships, learning investments, and attitude toward the firm

Understanding the consequences of customer steering is a key challenge of multichannel customer management. Although many firms are faced with the question whether customers should be steered to the online channel to realize the potential benefits of this channel, little is known about the circumstances under which customers will be unreceptive to the online channel and displeased if they are steered. This research addresses this critical gap and examines the impact of customer steering with assortment modifications on customers' online migration decisions and overall satisfaction in three experimental studies. The results highlight the importance of three contingency factors: personal relationships in the current channel, learning investments into the online channel and attitude toward the steering firm

Predictors of disease worsening defined by progression of organ damage in diffuse systemic sclerosis: a European Scleroderma Trials and Research (EUSTAR) analysis.

Objectives Mortality and worsening of organ function are desirable endpoints for clinical trials in systemic sclerosis (SSc). The aim of this study was to identify factors that allow enrichment of patients with these endpoints, in a population of patients from the European Scleroderma Trials and Research group database. Methods Inclusion criteria were diagnosis of diffuse SSc and follow-up over 12\ub13 months. Disease worsening/organ progression was fulfilled if any of the following events occurred: new renal crisis; decrease of lung or heart function; new echocardiography-suspected pulmonary hypertension or death. In total, 42 clinical parameters were chosen as predictors for the analysis by using (1) imputation of missing data on the basis of multivariate imputation and (2) least absolute shrinkage and selection operator regression. Results Of 1451 patients meeting the inclusion criteria, 706 had complete data on outcome parameters and were included in the analysis. Of the 42 outcome predictors, eight remained in the final regression model. There was substantial evidence for a strong association between disease progression and age, active digital ulcer (DU), lung fibrosis, muscle weakness and elevated C-reactive protein (CRP) level. Active DU, CRP elevation, lung fibrosis and muscle weakness were also associated with a significantly shorter time to disease progression. A bootstrap validation step with 10 000 repetitions successfully validated the model. Conclusions The use of the predictive factors presented here could enable cohort enrichment with patients at risk for overall disease worsening in SSc clinical trial

Does regression of skin thickening predict improvement of internal organ involvement and survival in patients with diffuse cutaneous systemic sclerosis? A EUSTAR analysis

Objective: Patients with diffuse cutaneous systemic sclerosis (dcSSc) frequently show spontaneous improvement of skin fibrosis. Our aim was to examine whether an improvement in skin fibrosis predicts lower likelihood of visceral organ progression and better survival. Methods: Patients from the European Scleroderma Trials and Research (EUSTAR) cohort with dcSSc, baseline modified Rodnan skin score (mRSS) ≥7, and valid mRSS at 12±3 months follow up were included. Regression/progression of skin fibrosis was defined as a decrease/increase in mRSS &gt;5 points and≥25% from baseline to follow up. The outcomes included progression of lung, renal, cardiac and gastrointestinal manifestations using consensus derived definitions and all-cause death. Regressive, stable and progressive patients were compared by univariate, Kaplan-Meier survival curve and Cox regression analysis. Results: Of 1257 included patients, 883 (70.2%) were stable, 282 (22.4%) regressive, and 92 (7.3%) progressive. Regressive patients, adjusted for baseline mRSS, baseline immunosuppression, baseline FVC, and disease duration, showed a significantly lower probability of FVC decline ≥10% than progressive patients (p=0.00003), lower probability of all-cause mortality during follow up (p=0.035) compared to progressive patients.Improvement of skin fibrosis was not associated with progression of other organ manifestations. Conclusion: We found that regression of skin fibrosis is associated with a lower probability of lung progression and better survival at follow up. The link between the disease course of skin and lung fibrosis in SSc can help to better stratify patients in clinical practice and enrich for ILD progressive patients in clinical trials

Progressive skin fibrosis is associated with a decline in lung function and worse survival in patients with diffuse cutaneous systemic sclerosis in the European Scleroderma Trials and Research (EUSTAR) cohort.

Objectives To determine whether progressive skin fibrosis is associated with visceral organ progression and mortality during follow-up in patients with diffuse cutaneous systemic sclerosis (dcSSc). Methods We evaluated patients from the European Scleroderma Trials and Research database with dcSSc, baseline modified Rodnan skin score (mRSS) ≥7, valid mRSS at 12±3 months after baseline and ≥1 annual follow-up visit. Progressive skin fibrosis was defined as an increase in mRSS &gt;5 and ≥25% from baseline to 12±3 months. Outcomes were pulmonary, cardiovascular and renal progression, and all-cause death. Associations between skin progression and outcomes were evaluated by Kaplan-Meier survival analysis and multivariable Cox regression. Results Of 1021 included patients, 78 (7.6%) had progressive skin fibrosis (skin progressors). Median follow-up was 3.4 years. Survival analyses indicated that skin progressors had a significantly higher probability of FVC decline ≥10% (53.6% vs 34.4%; p&lt;0.001) and all-cause death (15.4% vs 7.3%; p=0.003) than non-progressors. These significant associations were also found in subgroup analyses of patients with either low baseline mRSS (≤22/51) or short disease duration (≤15 months). In multivariable analyses, skin progression within 1 year was independently associated with FVC decline ≥10% (HR 1.79, 95% CI 1.20 to 2.65) and all-cause death (HR 2.58, 95% CI 1.31 to 5.09). Conclusions Progressive skin fibrosis within 1 year is associated with decline in lung function and worse survival in dcSSc during follow-up. These results confirm mRSS as a surrogate marker in dcSSc, which will be helpful for cohort enrichment in future trials and risk stratification in clinical practice