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This paper introduces a novel method for characterizing fracture mechanisms in multi-component materials using 3D image data gained by X-ray computed tomography (CT) measurements. In mineral liberation, the understanding of these mechanisms is crucial, particularly whether fractures occur along the boundaries of mineral phases (intergranular fracture) and/or within mineral phases (transgranular fracture). Conventional techniques for analyzing fracture mechanisms are focused on globally comparing the surface exposure of mineral phases extracted from image measurements before and after fracture. Instead, we present a virtual reassembling algorithm based on image registration techniques, which is applied to 3D data of multi-component materials before and after fracture in order to determine and characterize the individual fracture surfaces. This enables us to conduct a local quantitative analysis of fracture mechanisms by voxelwise comparing adjacent regions at fracture surfaces. A quantitative analysis of fracture mechanisms is especially important in the context of recycling processes. As primary deposits are decreasing worldwide and the focus is shifting on reducing wast, the interest in secondary raw materials has increased. However, lower-concentrated, but valuable materials are often overlooked in recycling routes designed for higher-concentration materials and dissipate. Therefore, efforts are being made to enrich valuable elements, such as lithium, as engineered artificial minerals through pyrometallurgical processes. The subsequent liberation through comminution processes, such as crushing, is essential for the recovery of valuable minerals. A better understanding of crushing processes, especially fracture mechanisms in slags, is crucial for the success of recycling. The reassembling algorithm presented in this paper is evaluated through a simulation study, followed by an application to a naturally occurring ore and a slag resulting from a recycling process. • Development of an algorithm for the characterisation of fracture mechanisms. • Analysis of fracture mechanisms by voxel-wise comparison of fracture surfaces. • Quantification of inter- and/or transgranular fracture in multi-component materials. • Insight into comminution processes for the recycling of valuable minerals from slag. [ABSTRACT FROM AUTHOR]

Segmentation of mm-resolution image data of irregularly shaped objects poses challenges to existing segmentation algorithms. This is especially true, when imperfections like noise, uneven lightning or traces of sample preparation are present in the image data. In this paper, considering electron micrographs of femoral quadriceps nerve sections of mice, a segmentation method to extract single axons surrounded by myelin sheaths is developed which is able to cope with various imperfections and artefacts. This approach successfully combines established methods like local thresholding and marker-based watershed transform to achieve a reliable segmentation of the given data. Indeed, the resulting segmentation map can be used to quantitatively determine geometrical characteristics of the axons and myelin sheaths. This is exemplified by modelling the joint probability distribution of axon area and myelin sphericity using a parametric copula approach, and by analysing the evolution of the model parameters for image data obtained from mice of different ages. [ABSTRACT FROM AUTHOR]

The unfolded protein response is an intricate system of sensor proteins in the endoplasmic reticulum (ER) that recognizes misfolded proteins and transmits information via transcription factors to either regain proteostasis or, depending on the severity, to induce apoptosis. The main transmembrane sensor is IRE1α, which contains cytoplasmic kinase and RNase domains relevant for its activation and the mRNA splicing of the transcription factor XBP1. Mast cell leukemia (MCL) is a severe form of systemic mastocytosis. The inhibition of IRE1α in the MCL cell line HMC-1.2 has anti-proliferative and pro-apoptotic effects, motivating us to elucidate the IRE1α interactors/regulators in HMC-1.2 cells. Therefore, the TurboID proximity labeling technique combined with MS analysis was applied. Gene Ontology and pathway enrichment analyses revealed that the majority of the enriched proteins are involved in vesicle-mediated transport, protein stabilization, and ubiquitin-dependent ER-associated protein degradation pathways. In particular, the AAA ATPase VCP and the oncoprotein MTDH as IRE1α-interacting proteins caught our interest for further analyses. The pharmacological inhibition of VCP activity resulted in the increased stability of IRE1α and MTDH as well as the activation of IRE1α. The interaction of VCP with both IRE1α and MTDH was dependent on ubiquitination. Moreover, MTDH stability was reduced in IRE1α-knockout cells. Hence, pharmacological manipulation of IRE1α–MTDH–VCP complex(es) might enable the treatment of MCL. [ABSTRACT FROM AUTHOR]

Investigates which general results concerning the local stability of steady states of arbitrary chemical reaction networks can be deduced with the Glansdorff-Prigogine stability criterion. Thermodynamic stability analysis of arbitrary mass-action kinetic reaction networks; Mass-action kinetic system with Hopf bifurcation consist of nonautocatalytic reactions.

Autophagy is a ubiquitous catabolic process, which causes cellular bulk degradation through vesicular engulfment of obsolete, damaged or harmful cytoplasmic components. While autophagy regulates cellular homeostasis during development and in youth, there is mounting evidence that autophagy becomes increasingly dysfunctional with age. Recent work in Caenorhabditis elegans even suggests that late‐life dysfunctional autophagy exhibits detrimental effects that drive the ageing process. Other studies link elevated autophagy closely to increased health and longevity. This review aims to put these apparently opposing views into perspective and define our current understanding of the role of autophagy during ageing. [ABSTRACT FROM AUTHOR]

Background. Posttonsillectomy hemorrhage (PTH) is the most feared complication. Dissection near the tonsillar capsule under microscopic view (TEmic) could be assumed to decrease PTH compared to traditional tonsillectomy (TEtrad). Methods. In this study, patients were evaluated with respect to the need for surgical control (R/N: return/no return to theater (RTT): the day of surgery [0] or thereafter [1]). The findings at resection site and pain were measured. Results. 869 patients were included (183 TEmic; 686 TEtrad). PTH requiring RTT was not seen in the TEmic group on the day of surgery (R0) while PTH requiring RTT subsequently (R1) was seen in 1.1% of the cases. In the TEmic group, hemorrhages without a need for surgical control were observed in 0.6% (N0) and 3.4% (N1), respectively. The corresponding rates for TEtrad were as follows: R0, 0.3%; R1, 1.7%; N0, 0.6%; and N1, 3.6% (p>0.05). Postoperative edema and local infection at resection site were proven to be predictive of PTH (p=0.007). Conclusion. Microscope assistance in tonsillectomy did not statistically have an influence on the PTH even though there was a trend towards lower PTH rate in the TEmic group. Benefit for TEmic was observed in high-volume and long experienced surgeons. [ABSTRACT FROM AUTHOR]

Involvement of the middle ear after viral infections of the upper airways may lead to serous otitis media with effusion in the absence of bacterial infection. This can be accompanied by a concomitant shading of the mastoid air cells, which could manifest as a reduced opacity on computed tomography (CT) in the absence of a history of chronic mastoiditis or acute inflammatory signs. This can lead to a subsequent impairment of inner ear function. CT scans reveal an extended pneumatization of the temporal bones in affected patients. Inner ear hearing impairment can probably be attributed to a concomitant labyrinthine reaction—the so-called toxic inner ear lesion. If no remission occurs within 5 days after initial conservative treatment (paracentesis or hemorrheologic infusions), surgical treatment with a mastoidectomy can accelerate hearing restoration. We conducted a retrospective, nonrandomized study of short- and long-term hearing outcomes in patients with a toxic inner ear lesion who had been treated with conservative measures alone (CONS group) or with surgery (SURG group) in a tertiary care referral center. Our study group was made up of 52 consecutively presenting patients (57 ears) who had been seen over a 10-year period; there were 20 patients (21 ears) in the CONS group and 32 patients (36 ears) in the SURG group. Initially, 15 CONS patients (75%) and 18 SURG patients (56%) complained of dizziness or a balance disorder. The initial averaged sensorineural hearing loss (over 0.5, 1.0, 2.0, and 3.0 kHz) was 32.4 ± 15.6 dB in the CONS group and 35.4 ± 12.0 dB in the SURG group. At follow-up (mean: 31.7 mo), the SURG group experienced a significantly greater improvement in hearing (p = 0.025). We conclude that patients with viral otitis media and concomitant noninflammatory mastoiditis with impairment of inner ear function (sensorineural hearing loss) experience a better hearing outcome when a mastoidectomy is performed during primary treatment. [ABSTRACT FROM AUTHOR]

Background: Antigen (Ag)/IgE-mediated mast cell (MC) responses play detrimental roles in allergic diseases. MC activation via the high-affinity receptor for IgE (FceRI) is controlled by the Src family kinase Lyn. Lyn-deficient (-/-) bone marrow-derived MCs (BMMCs) have been shown by various laboratories to exert stronger activation of the PI3K pathway, degranulation, and production of pro-inflammatory cytokines compared to wild-type (wt) cells. This mimics the phenotype of BMMCs deficient for the SH2-containing inositol-5'-phosphatase 1 (SHIP1). In this line, Lyn has been demonstrated to tyrosine-phosphorylate and activate SHIP1, thereby constituting a negative feedback control of PI3K-mediated signals. However, several groups have also reported on Lyn-/- BMMCs degranulating weaker than wt BMMCs. Results: Lyn-/- BMMCs, which show a suppressed degranulation response, were found to exhibit abrogated tyrosine phosphorylation of SHIP1 as well. This indicated that even in the presence of reduced SHIP1 function MC degranulation is dependent on Lyn function. In contrast to the reduced immediate secretory response, pro-inflammatory cytokine production was augmented in Lyn-/- BMMCs. For closer analysis, Lyn/SHIP1-double-deficient (dko) BMMCs were generated. In support of the dominance of Lyn deficiency, dko BMMCs degranulated significantly weaker than SHIP1-/- BMMCs. This coincided with reduced LAT1 and PLC-γ1 phosphorylation as well as Ca2+ mobilization in those cells. Interestingly, activation of the NFκB pathway followed the same pattern as measured by IκBα phosphorylation/degradation as well as induction of NFκB target genes. This suggested that Ag-triggered NFκB activation involves a Ca2+-dependent step. Indeed, IκBα phosphorylation/degradation and NFκB target gene induction were controlled by the Ca2+-dependent phosphatase calcineurin. Conclusions: Lyn deficiency is dominant over SHIP1 deficiency in MCs with respect to Ag-triggered degranulation and preceding signaling events. Moreover, the NFκB pathway and respective targets are activated in a Lyn- and Ca2+-dependent manner, reinforcing the importance of Lyn for MC activation. [ABSTRACT FROM AUTHOR]

Viral infections of the upper respiratory airways can lead to a delayed viral otitis media (VOM) caused by a diffusion of viruses/virus particles through the round window membrane and resulting in sensorineural hearing loss. The treatment of choice is immediate paracentesis, evacuation of all fluids from the middle ear cavity, and haemorrheological infusions. However, in some cases, persistent symptoms may be an indication for a surgical approach using mastoidectomy. In high-resolution computed tomography, an extended small-sized pneumatisation of the mastoid cells with complete shading was found in these non-responsive cases. Therefore, a direct means of inner ear affliction through weak parts of the labyrinthine bone may be hypothesised. Patients suffering from a toxic inner ear lesion (TIEL) following a common cold, treated over a 10-year period in a Tertiary Care Centre ( N = 52, 57 ears), were identified and the morphological characteristics of the temporal bones of affected patients were examined by means of high-resolution computed tomography (hrCT). The findings were compared with a matched control group of 64 normal ears (CONT). Measurements included the grade of pneumatisation, distances within the temporal bones and Hounsfield units (HU) at defined anatomical structures. In the TIEL group, we found a small-sized pneumatisation in 79.4 % and a medium-sized pneumatisation in 10.9 %, thus differing from the CONT group and the literature data. Thickness of the bone wall of the lateral semicircular canal (LSC) and distances within the aditus ad antrum were significantly reduced in the TIEL group. HU's were markedly lower in the TIEL group at the precochlea, the LSC, and dorsolateral to the promentia of the LSC. There was a correlation between the HU's at the prominentia of the LSC and the hearing loss ( p = 0.002). Persisting interosseous globuli, as described in 1897 by Paul Manasse, form an osseochondral network within the otic capsule and may be responsible for a direct means of toxic inner ear infection. The CT-morphometric results support this thesis. In the group of these patients (TIEL) a CT-scan and in non-responders to conservative treatment a surgical approach by mastoidectomy is recommended. [ABSTRACT FROM AUTHOR]

Lehrmittelfirmen bieten für viele physikalische Größen eigene externe Sensoren an, die nicht nur vom PC, sondern auch vom Tablet oder Smartphone ausgelesen werden können. Dies kann beispielsweise genutzt werden, um den hydrostatischen Druck in Abhängigkeit von der Tiefe zu messen. [ABSTRACT FROM AUTHOR]

Background DNA methylation (DNAm) has important regulatory roles in many biological processes and diseases. It is the only epigenetic mark with a clear mechanism of mitotic inheritance and the only one easily available on a genome scale. Aberrant cytosine-phosphate-guanine (CpG) methylation has been discussed in the context of disease aetiology, especially cancer. CpG hypermethylation of promoter regions is often associated with silencing of tumour suppressor genes and hypomethylation with activation of oncogenes. Supervised principal component analysis (SPCA) is a popular machine learning method. However, in a recent application to phenotype prediction from DNAm data SPCA was inferior to the specific method EVORA. Results We present Model-Selection-SPCA (MS-SPCA), an enhanced version of SPCA. MS-SPCA applies several models that perform well in the training data to the test data and selects the very best models for final prediction based on parameters of the test data. We have applied MS-SPCA for phenotype prediction from genome-wide DNAm data. CpGs used for prediction are selected based on the quantification of three features of their methylation (average methylation difference, methylation variation difference and methylation-age-correlation). We analysed four independent case-control datasets that correspond to different stages of cervical cancer: (i) cases currently cytologically normal, but will later develop neoplastic transformations, (ii, iii) cases showing neoplastic transformations and (iv) cases with confirmed cancer. The first dataset was split into several smaller case-control datasets (samples either Human Papilloma Virus (HPV) positive or negative). We demonstrate that cytology normal HPV+ and HPV- samples contain DNAm patterns which are associated with later neoplastic transformations. We present evidence that DNAm patterns exist in cytology normal HPV- samples that (i) predispose to neoplastic transformations after HPV infection and (ii) predispose to HPV infection itself. MS-SPCA performs significantly better than EVORA. Conclusions MS-SPCA can be applied to many classification problems. Additional improvements could include usage of more than one principal component (PC), with automatic selection of the optimal number of PCs. We expect that MS-SPCA will be useful for analysing recent larger DNAm data to predict future neoplastic transformations. [ABSTRACT FROM AUTHOR]

Eine Simulation zum senkrechten Stoß auf eine rollende Kugel hilft Lernenden, den Kraftbegriff in der Newtonschen Dynamik zu verstehen. [ABSTRACT FROM AUTHOR]

Mit der App Science Journal kann man nicht nur die Daten der integrierten Sensoren auslesen, sondern hat darüber hinaus ein digitales Notizbuch für verschiedene Experimente an einem Ort. [ABSTRACT FROM AUTHOR]

Eine Smartphone‐App macht es möglich, die Internationale Raumstation ISS am Nachthimmel zu orten und ihre Flugbahn zu beobachten. [ABSTRACT FROM AUTHOR]

Mit eigens für die Videoanalyse geschaffenen Apps lassen sich komplexe Bewegungsabläufe mit Smartphone oder Tablet schnell und bequem „out‐of‐the‐box" analysieren. Ein Beispiel dafür ist die im Folgenden vorgestellte iPad‐App NewtonDV. [ABSTRACT FROM AUTHOR]

Mit Hilfe eines Smartphones lässt sich ermitteln, wo es bei einem Gewitter geblitzt hat und ob das Gewitter näherkommt. [ABSTRACT FROM AUTHOR]

We present a simple, intuitive, and effective approach for network clustering. It is based on basic concepts of linear algebra such as efficient calculation of spanning trees, and can be implemented in a few lines of code. We introduce the node separation measure spanning tree separation (STS) and the corresponding graph distance measure spanning tree vector similarity distance (STVSD). We demonstrate that the STS is a link salience measure able to identify the backbone of networks. The STVSD is used to reveal the hierarchical community structure of networks. We show that it, together with the clustering quality measure partition density, is on a par with the best graph or network clustering methods known, in terms of both quality and efficiency. In perspective, we note that our approach could also handle weighted and directed networks and could be used for identification of overlapping communities. [ABSTRACT FROM AUTHOR]

In drug discovery, the characterisation of the precise modes of action (MoA) and of unwanted off-target effects of novel molecularly targeted compounds is of highest relevance. Recent approaches for identification of MoA have employed various techniques for modeling of well defined signaling pathways including structural information, changes in phenotypic behavior of cells and gene expression patterns after drug treatment. However, efficient approaches focusing on proteome wide data for the identification of MoA including interference with mutations are underrepresented. As mutations are key drivers of drug resistance in molecularly targeted tumor therapies, efficient analysis and modeling of downstream effects of mutations on drug MoA is a key to efficient development of improved targeted anti-cancer drugs. Here we present a combination of a global proteome analysis, reengineering of network models and integration of apoptosis data used to infer the mode-of-action of various tyrosine kinase inhibitors (TKIs) in chronic myeloid leukemia (CML) cell lines expressing wild type as well as TKI resistance conferring mutants of BCR-ABL. The inferred network models provide a tool to predict the main MoA of drugs as well as to grouping of drugs with known similar kinase inhibitory activity patterns in comparison to drugs with an additional MoA. We believe that our direct network reconstruction approach, demonstrated on proteomics data, can provide a complementary method to the established network reconstruction approaches for the preclinical modeling of the MoA of various types of targeted drugs in cancer treatment. Hence it may contribute to the more precise prediction of clinically relevant on- and off-target effects of TKIs. [ABSTRACT FROM AUTHOR]

This study investigated the influence of viscose fibre (VF) geometry on the microstructures and resulting properties of high-density polyethylene (HDPE) composites. Seven types of viscose fibres varying in cross-section shape, linear density, and length were pelletised, compounded into HDPE with a twin-screw extruder, and injection moulded. The microstructures of the composites were characterised by investigating their cross-sections and by extracting the fibres and measuring their lengths using optical microscopy (OM). The mechanical and thermal properties of the composites were characterised using differential scanning calorimetry (DSC), tensile tests, Charpy impact tests, and dynamic mechanical analysis (DMA). The composites prepared using cylindrical fibres with a linear density of 1.7 dtex exhibited the best fibre dispersion, highest orientation, and lowest fibre–fibre contact area. The decrease in the linear density of the cylindrical fibres resulted in increasingly worse dispersion and orientation, while composites containing non-cylindrical fibres exhibited a comparably larger fibre–fibre contact area. The initial fibre length of about 3 to 10 mm decreased to the mean values of 0.29 mm to 0.41 mm during processing, depending on the initial geometry. In general, cylindrical fibres exhibited a superior reinforcing effect in comparison to non-cylindrical fibres. The composites containing cylindrical fibres with a linear density of 1.7 dtex and a length of 5 mm exhibited the best reinforcing effect with an increase in tensile modulus and strength of 323% and 141%, respectively. [ABSTRACT FROM AUTHOR]

Activation of mast cells (MCs) can be achieved by the high-affinity receptor for IgE (FceRI) as well as by additional receptors such as the lipopolysaccharide (LPS) receptor and the receptor tyrosine kinase Kit (stem cell factor [SCF] receptor). Thus, pharmacological interventions which stabilize MCs in response to different receptors would be preferable in diseases with pathological systemic MC activation such as systemic mastocytosis. 1,4-Benzodiazepines (BDZs) have been reported to suppress MC effector functions. In the present study, our aim was to analyze molecularly the effects of BDZs on MC activation by comparison of the effects of the two BDZs Ro5-4864 and clonazepam, which markedly differ in their affinities for the archetypical BDZ recognition sites, i.e., the GABAA receptor and TSPO (previously termed peripheral-type BDZ receptor). Ro5-4864 is a selective agonist at TSPO, whereas clonazepam is a selective agonist at the GABAA receptor. Ro5-4864 suppressed pro-inflammatory MC effector functions in response to antigen (Ag) (degranulation/cytokine production) and LPS and SCF (cytokine production), whereas clonazepam was inactive. Signaling pathway analyses revealed inhibitory effects of Ro5-4864 on Ag-triggered production of reactive oxygen species, calcium mobilization and activation of different downstream kinases. The initial activation of Src family kinases was attenuated by Ro5-4864 offering a molecular explanation for the observed impacts on various downstream signaling elements. In conclusion, BDZs structurally related to Ro5-4864 might serve as multifunctional MC stabilizers without the sedative effect of GABAA receptorinteracting BDZs. [ABSTRACT FROM AUTHOR]

Abstract: During the development of a transoral endoscopic, minimally invasive approach for thyroidectomy, the question arose as to how the distances of the submandibular gland (SG)–hyoid bone (HB)–thyroid gland (TG) change in differing head positions and how the TG itself changes shape. In a prospective, two-armed ultrasound study we studied 20 healthy volunteers each, all with no history of neck surgery or thyroid disease. Distances were measured in normal, reclined and “reclined with open mouth” positions. We found no remarkable differences and the distances were comparable with conventional open or minimally invasive thyroidectomy approaches. The TG lengthened significantly during reclination. This may result in a difficult preparation in the region of the suspensory ligament and may therefore increase the rate of postoperative vocal cord palsy caused by stretching of the recurrent laryngeal nerve. A supine flat position may minimize the risk of this postoperative complication of thyroidectomy. [Copyright &y& Elsevier]

Background: In anatomical studies and cadaver dissections, we developed an endoscopic transoral access to the anterior neck region to reduce surgical access trauma. Through a sublingual trocar and two additional trocars in the vestibule of the oral cavity, the pretracheal and thyroid region was reached with standard laparoscopic instruments. Methods: We conducted an experimental trial in five pigs under general anesthesia to estimate the safety and feasibility of the method; via this approach, the thymus was partially resected. Perioperative antibiotics were administered but analgesics were not given in the postoperative course. Oral intake and behavior were observed during the following 2 days. After necropsy, examination of the access route took place by means of dissections. The tissue surrounding the working trocar was histologically examined. Results: The pretracheal region could be reached without a problem and the procedure was performed almost 'bloodlessly' in an anatomically defined layer. The intervention time decreased successively. Postoperative awakening was uneventful. Regular oral food intake was observed after 2-3 h. Pain reactions were not registered during the entire postoperative phase. After dissection, all relations appeared inconspicuous (no infections, fresh/old hematoma). Two local encapsulated seromas were observed. Histologically, only a mild tissue reaction was noted. Conclusion: In this study, the endoscopic transoral approach to minimally invasive neck surgery seemed safe and feasible. Minimally invasive endoscopic procedures in the anterior neck region could be a possible application of this new approach. [ABSTRACT FROM AUTHOR]

Abstract: Objective: In recent years, several surgical disciplines adopted endoscopic techniques. Presently, natural orifice approaches are under exploration to reduce surgical access trauma. We have developed a trans-oral endoscopic approach for endoscopic mediastinal surgery and have tested this new technique in preclinical studies for feasibility and safety. Methods: We conducted an experimental anatomical study in fresh-frozen cadavers. By a midline, sublingual incision, we placed an optical scissor through a 6.0-mm trocar in the pretracheal region and created a working space; two additional trocars were placed by bi-vestibular incisions in the oral cavity. We visualized and followed the trachea down to the main bronchi. Paratracheal and subcarinal lymph nodes were resected bilaterally; the specimen could be removed through the midline channel. In an additional animal study in pigs, we tested the feasibility and safety for this surgical approach. Anatomical dissection allowed an estimate of collateral damage. Results: In all cases, we could reach the target region endoscopically, and no conversion was necessary. Landmarks (the brachiocervical trunk, the azygos vein, and the pulmonary artery) were visualized easily and kept intact. A working space in the mediastinum could be established by the insufflation of air at 6–8mmHg. It was possible to harvest the specimen through the midline channel. Anatomical dissection of the cervical access route as well as of the mediastinal region showed no collateral damage. In the animal study, we encountered seroma of the surgical field due to the conditions of the animal model. The other outcomes with respect to pain and food intake were normal until the third postoperative day. No local infections occurred. Intraoperative gas exchange was normal and was not influenced by CO2 insufflation with respect to blood gas analysis. Conclusion: These preclinical studies showed that the mediastinum could be reached by a trans-oral endoscopic approach, based on natural orifice surgery. Complete compartment resection of the paratracheal and subcarinal lymph node stations was possible in a well-defined and clearly visible working space. This approach may enhance the extent of mediastinal resections in oncologic surgery. [Copyright &y& Elsevier]

Background: We have developed a new approach for endoscopic minimally invasive thyroidectomy (eMIT) in anatomical studies. Safety and feasibility were demonstrated in an animal study and then the eMIT technique was applied for the first time successfully in humans on the 18 March 2009. Methods: In a prospective study, we performed this eMIT technique on eight patients suffering from nodular change of the thyroid gland. All patients were evaluated regarding recurrent laryngeal nerve function, intra- and postoperative complications, and postoperative outcome, particularly with respect to swallowing disorders. Results: A total thyroidectomy and a partial resection were performed in four cases each. In three cases, a conversion to open surgery was necessary due to specimen size. No local infection at the incision site or within the cervical spaces occurred within the direct postoperative course. No intraoperative bleeding necessitating conversion to open surgery was observed. In one case, a permanent palsy of the right recurrent laryngeal nerve was noted. Voice function and breathing were not affected. Paresthesia of the mental nerve did not occur in all patients and in those in which it did occur, it resolved within 3 weeks. Mean follow-up time was 10.9 months. Conclusions: The experimental development of the eMIT technique has led to its first clinical application in humans. In this prospective proof-of-concept study in humans, the thyroid gland was reached via the transoral endoscopic approach in an anatomically defined layer without any relevant damage to vessels. Limitations to this technique are determined by specimen volume (up to 30 ml) and nodule size (up to 20 mm). [ABSTRACT FROM AUTHOR]

Background The transoral endoscopic approach for thyroid surgery was based on a previous attempt to reach the thyroid gland by an axilloscope. In contrast to this single-port access, endoscopic minimally invasive thyroidectomy (eMIT) uses three access points (sublingual and bivestibular). This results in a sufficient triangulation of instruments, making surgical procedures in the anterior neck region possible. Methods The idea and development of the eMIT technique are described in detail. Anatomic studies, the development of the surgical access in a cadaver study, and the animal study for safety and feasibility of this transoral endoscopic approach for surgery of the anterior neck are outlined. Also, the foundations and ethical aspects are addressed in the context of developing a surgical innovation, which resulted in the first clinical application of this technique in humans. Results The preclinical studies regarding endoscopic minimally invasive thyroidectomy proofed feasibility in a human cadaver studies as well as safety in a short-time survival animal study. The first clinical application in a 53- year old patient was successful without any significant complications; expected benefits (no postoperative pain or dysphagia, no visible scar) could be demonstrated. Conclusions The eMIT technique represents a promising new surgical approach for endoscopic surgery in the anterior neck region. The whole development was based on principles for surgical innovation published after the authors’ preclinical studies. At this writing, after an initial clinical study with humans, the time has come to compare this new technique with other endoscopic and minimally invasive approaches in a prospective randomized multicenter trial. [ABSTRACT FROM AUTHOR]

Over the past 10 years, several minimally invasive procedures for thyroid surgery have been developed. Because of extensive dissection in the thoracic and neck region, the name “minimal-invasive” is misleading. The aim of this study was to define a new trans-oral access to the cervical spaces especially to the thyroid on the basis of natural orifice surgery. Three embalmed human specimens were dissected for complete review of the anatomical situation in the cervical region. In additional five fresh frozen human specimens after an experimental trans-oral endoscopic minimally invasive thyroidectomy the anatomical structures of the floor of the oral cavity as well as the anterior neck region were evaluated. It was possible to create a working space under the platysma muscle with respect to the surgical planes of the neck and fascial layers. Within this area, the pretracheal region can be reached and the thyroid gland can be visualized and resected. To access the working space, a trocar for endoscopic view is placed medially in the floor of the oral cavity sublingually. The trocar passes the muscles of the floor of the oral cavity easily without relation to relevant anatomical structures. A first exclusively sublingual approach had to be abandoned because triangulation of the instruments could not be reached. Therefore, the approach was modified by positioning the working trocars in the oral vestibule bilaterally. By this way, a road map for accessing all anterior cervical regions directly under the platysma muscle could be established and anatomical landmarks and areas of possible collateral damage could have been defined. This combined sublingual and bi-vestibular trans-oral endoscopic approach enables an easy access to all structures and spaces of the anterior neck region with respect to anatomical preformed layers neck, even to the thyroid as one of the more distant structures. [ABSTRACT FROM AUTHOR]

Die App Physics Toolbox Light Sensor misst mit Hilfe des integrierten Lichtsensors die Beleuchtungsstärke. Damit können beispielsweise unterschiedliche Kompaktleuchtstoffröhren, auch bekannt als Energiesparlampen, genauer untersucht werden. [ABSTRACT FROM AUTHOR]

Abstract: We present a generalised framework for analysing structural robustness of metabolic networks, based on the concept of elementary flux modes (EFMs). Extending our earlier study on single knockouts [Wilhelm, T., Behre, J., Schuster, S., 2004. Analysis of structural robustness of metabolic networks. IEE Proc. Syst. Biol. 1(1), 114–120], we are now considering the general case of double and multiple knockouts. The robustness measures are based on the ratio of the number of remaining EFMs after knockout vs. the number of EFMs in the unperturbed situation, averaged over all combinations of knockouts. With the help of simple examples we demonstrate that consideration of multiple knockouts yields additional information going beyond single-knockout results. It is proven that the robustness score decreases as the knockout depth increases. We apply our extended framework to metabolic networks representing amino acid anabolism in Escherichia coli and human hepatocytes, and the central metabolism in human erythrocytes. Moreover, in the E. coli model the two subnetworks synthesising amino acids that are essential and those that are non-essential for humans are studied separately. The results are discussed from an evolutionary viewpoint. We find that E. coli has the most robust metabolism of all the cell types studied here. Considering only the subnetwork of the synthesis of non-essential amino acids, E. coli and the human hepatocyte show about the same robustness. [Copyright &y& Elsevier]

Abstract: Many papers published in recent years show that real-world graphs ( nodes, edges) are more or less “complex” in the sense that different topological features deviate from random graphs. Here we narrow the definition of graph complexity and argue that a complex graph contains many different subgraphs. We present different measures that quantify this complexity, for instance , the relative number of non-isomorphic one-edge-deleted subgraphs (i.e. DECK size). However, because these different subgraph measures are computationally demanding, we also study simpler complexity measures focussing on slightly different aspects of graph complexity. We consider heuristically defined “product measures”, the products of two quantities which are zero in the extreme cases of a path and clique, and “entropy measures” quantifying the diversity of different topological features. The previously defined network/graph complexity measures Medium Articulation and Offdiagonal complexity (OdC) belong to these two classes. We study OdC measures in some detail and compare it with our new measures. For all measures, the most complex graph has a medium number of edges, between the edge numbers of the minimum and the maximum connected graph . Interestingly, for some measures this number scales exactly with the geometric mean of the extremes: . All graph complexity measures are characterized with the help of different example graphs. For all measures the corresponding time complexity is given. Finally, we discuss the complexity of 33 real-world graphs of different biological, social and economic systems with the six computationally most simple measures (including OdC). The complexities of the real graphs are compared with average complexities of two different random graph versions: complete random graphs (just fixed ) and rewired graphs with fixed node degrees. [Copyright &y& Elsevier]

Abstract: We present a new information theoretic approach for network characterizations. It is developed to describe the general type of networks with n nodes and L directed and weighted links, i.e., it also works for the simpler undirected and unweighted networks. The new information theoretic measures for network characterizations are based on a transmitter–receiver analogy of effluxes and influxes. Based on these measures, we classify networks as either complex or non-complex and as either democracy or dictatorship networks. Directed networks, in particular, are furthermore classified as either information spreading and information collecting networks. The complexity classification is based on the information theoretic network complexity measure medium articulation (MA). It is proven that special networks with a medium number of links () show the theoretical maximum complexity . A network is complex if its is larger than the average MA of appropriately randomized networks: . A network is of the democracy type if its redundancy , otherwise it is a dictatorship network. In democracy networks all nodes are, on average, of similar importance, whereas in dictatorship networks some nodes play distinguished roles in network functioning. In other words, democracy networks are characterized by cycling of information (or mass, or energy), while in dictatorship networks there is a straight through-flow from sources to sinks. The classification of directed networks into information spreading and information collecting networks is based on the conditional entropies of the considered networks ( of sender node if receiver node is known, of receiver node if sender node is known): if , it is an information collecting network, otherwise an information spreading network. Finally, different real networks (directed and undirected, weighted and unweighted) are classified according to our general scheme. [Copyright &y& Elsevier]

Abstract: Two approaches for the replacement of the toxic KCN etching step in the production of CuInS2 (CIS) absorber layers are presented. The electrochemical conditioning in acidic V2+/V3+ electrolyte comprises two treatment stages, the first one being the removal of covellite (CuS) at moderate anodic potentials and the second one the dissolution of a small sacrificial layer of CIS together with copper sulphide remnants at more aggressive potentials. This procedure yields absorber layers which are 3.3% efficient in photoelectrochemical solar cells (PECS) and 8% efficient in solid-state devices. The other approach is a combined electrochemical/chemical conditioning where the free energy of formation of a Cu–EDTA complex contributes to the copper sulphide dissolution and facilitates the removal of Cu–S phases at moderate electrochemical potentials. CIS films after this conditioning yield 1.44% in PECS. To cite this article: T. Wilhelm et al., C. R. Chimie 9 (2006) . [Copyright &y& Elsevier]

Abstract: We present the clinical, imaging and neuropathological findings in three patients with predominant brachial plexus neuropathy. MR scanning was key to determining the brachial plexus involvement. Biopsy of the brachial plexus was performed in one patient. The appearances of the brachial plexus on MRI, in conjunction with the clinical presentations of these patients, suggest that they are unusual variants within the spectrum of chronic inflammatory demyelinating polyradiculoneuropathy. [Copyright &y& Elsevier]

Im Zusammenspiel mit einem Bluetooth‐Verstärker kann man Smartphones als leistungsstarke, vielseitig einsetzbare Funktionsgeneratoren nutzen. [ABSTRACT FROM AUTHOR]

It is argued to study better non-binary (weighted) food webs where links are measured quantitatively, instead of binary (unweighted) food webs where links are just present or absent. Binary webs can simply be deduced from the more general non-binary ones: if a flux is larger than a critical flux value (below denoted by “cut”) a link is drawn, otherwise it is not. However, the amount of a flux between two nodes critically depends on the biomass of these nodes. Unfortunately, a clear definition of what to subsume into one node is missing up to now. The simplest (and probably most important) statistical description of non-binary food webs is given by the flux distribution function. However, this function may strongly be changed by just merging two nodes into one (as we have shown). In order to solve this decisive problem we propose to setup food webs with all nodes containing the same amount of biomass: equal-node-webs. A simple merging of just two nodes is forbidden here, because such a merged node would contain more biomass. The best basis for such a new food web theory would be provided by empirical equal-node-webs, established by field ecologists. However, such data has not been available up to now. Nevertheless, we demonstrate some advantages of studying equal-node-webs. For that purpose, first we show—by means of two example food webs—how equal-node-webs can be deduced from already published non-binary webs. Second, we describe the deduced equal-node-webs by their flux distribution functions as well as by different statistical measures. It is shown that equal-node-webs are more scale invariant than common non-binary food webs. Therefore, equal-node-webs provide a crucial, trustworthy basis for sound statistical descriptions and comparative analyses of food webs.Moreover, the article contains a new detailed comparison between a highly productive lake and a low productive one. It is shown that the food web of the latter has a higher complexity than that of the former. [Copyright &y& Elsevier]

Since the early days of the discovery of the genetic code nonrandom patterns have been searched for in the code in the hope of providing information about its origin and early evolution. Here we present a new classification scheme of the genetic code that is based on a binary representation of the purines and pyrimidines. This scheme reveals known patterns more clearly than the common one, for instance, the classification of strong, mixed, and weak codons as well as the ordering of codon families. Furthermore, new patterns have been found that have not been described before: Nearly all quantitative amino acid properties, such as Woese’s polarity and the specific volume, show a perfect correlation to Lagerkvist’s codon-anticodon binding strength. Our new scheme leads to new ideas about the evolution of the genetic code. It is hypothesized that it started with a binary doublet code and developed via a quaternary doublet code into the contemporary triplet code. Furthermore, arguments are presented against suggestions that a “simpler” code, where only the midbase was informational, was at the origin of the genetic code. [ABSTRACT FROM AUTHOR]

An elementary stochastic model, termed the normalization model, is put forward which does demonstrate that power-laws generically occur in systems with finite resources. The model is capable to exhibit power-law distributions with arbitrary power law exponents; nevertheless, for a large fraction of the parameter space power law exponents near unity are obtained.As an application of the normalization mechanism we consider a network growth-saturation model. This model extends the scale-free network model (SF) to include the fact of finite resources. In the network growth-saturation model the scale-free property holds only for the growth period, within the stationary regime we obtain power-law distributions of the weight of the edges among the vertices. We conjecture that this pattern will be found in the Internet if it reaches the steady state. [Copyright &y& Elsevier]

Paine [Ecology 69 (1988) 1648] called for a “dynamic rather than static” food web theory which should also take into account the “interaction strength” between the nodes. Here we face the challenge: an elementary food web model is presented which is both, dynamic and non-binary. We introduce the complexity measure for non-binary food webs “medium articulation” which resolves a contradiction in the discussion of stability of ecosystems. We propose a possible standard for establishment of food webs which avoids arbitrariness of both, nodes and links. After consideration of non-binary webs, binary webs are deduced by removing small fluxes and setting remaining fluxes to 1. Comparing both network types, it is argued that non-binary webs are more important than binary webs. [Copyright &y& Elsevier]

Electricity has shaped modern civilization in a way few other discoveries have. Nonetheless, few students successfully develop a basic understanding of voltage, current, and resistance or their mutual relationship in simple DC circuits. Despite teachers' best efforts in the classroom, so-called "alternative conceptions" often prevail after traditional instruction. In particular, voltage has proven to be a difficult concept to teach—many students erroneously think of voltage as a property of electric current. Furthermore, a battery is often considered to be a source of constant current rather than constant voltage. In order to help students develop a better understanding of simple DC circuits, we developed a new curriculum with an accompanying computer simulation that illustrates potential differences in circuits in order to make voltage rather than current the students' primary concept when analyzing circuits. To this end, the curriculum takes typical alternative conceptions into account and builds on students' everyday experiences with air pressure in order to provide them with an immediately tangible counterpart in electric potential. In analogy to air pressure differences that cause an air flow, voltage is introduced as an "electric pressure difference" that causes an electric current. Using the accompanying computer simulation, potential differences are visualized in simple DC circuits using color coding and a height representation. The new curriculum including teaching resources as well as the newly developed computer simulation are both freely available online to teachers and students alike. [ABSTRACT FROM AUTHOR]

Mit dem App AccelVisu für iPhone und iPod touch steht eine Möglichkeit zur Verfügung, gleichzeitig Richtung und Betrag einer beschleunigten Bewegungen direkt sichtbar zu machen. Dies kann sehr aufschlussreich für das grundlegende Verständnis von Beschleunigungen sein. [ABSTRACT FROM AUTHOR]

Physikalische Größen sind bei aerodynamischen Vorgängen schwer beobachtbar. Die App Wind Tunnel ermöglicht es, Zusammenhänge zu visualisieren und physikalische Größen zu berechnen. [ABSTRACT FROM AUTHOR]

In mast cells (MCs), the TEC family kinase (TFK) BTK constitutes a central regulator of antigen (Ag)-triggered, FcεRI-mediated PLCγ phosphorylation, Ca2+ mobilization, degranulation, and pro-inflammatory cytokine production. Less is known about the function of BTK in the context of stem cell factor (SCF)-induced KIT signaling. In bone marrow-derived MCs (BMMCs), Ag stimulation caused intense phosphorylation of BTK at Y551 in its active center and at Y223 in its SH3-domain, whereas in response to SCF only Y223 was significantly phosphorylated. Further data using the TFK inhibitor Ibrutinib indicated that BTK Y223 is phosphorylated by a non-BTK TFK upon SCF stimulation. In line, SCF-induced PLCγ1 phosphorylation was stronger attenuated by Ibrutinib than by BTK deficiency. Subsequent pharmacological analysis of PLCγ function revealed a total block of SCF-induced Ca2+ mobilization by PLC inhibition, whereas only the sustained phase of Ca2+ flux was curtailed in Ag-stimulated BMMCs. Despite this severe stimulus-dependent difference in inducing Ca2+ mobilization, PLCγ inhibition suppressed Ag- and SCF-induced degranulation and pro-inflammatory cytokine production to comparable extents, suggesting involvement of additional TFK(s) or PLCγ-dependent signaling components. In addition to PLCγ, the MAPKs p38 and JNK were activated by Ag in a BTK-dependent manner; this was not observed upon SCF stimulation. Hence, FcεRI and KIT employ different mechanisms for activating PLCγ, p38, and JNK, which might strengthen their cooperation regarding pro-inflammatory MC effector functions. Importantly, our data clearly demonstrate that analyzing BTK Y223 phosphorylation is not sufficient to prove BTK activation. Unlabelled Image • In contrast to Ag, SCF hardly induces BTK Y551 phosphorylation in BMMCs. • SCF/KIT signaling uses non-BTK TFKs for activating PLCγ1 tyrosine phosphorylation. • Synergistic quality of Ag plus SCF-induced TNF-α production is independent of BTK. • Analysis of BTK Y223 phosphorylation is not sufficient to prove BTK activation. [ABSTRACT FROM AUTHOR]

Here presented are the properties and performance of a new metallo‐dielectric waveguide array structure as the encapsulation material for silicon solar cells. The arrays are produced through light‐induced self‐writing combined with in situ photochemical synthesis of silver nanoparticles. Each waveguide comprises a cylindrical core consisting of a high refractive index polymer and silver nanoparticles homogenously dispersed in its medium, all of which are surrounded by a low refractive index common cladding. The waveguide array‐based films are processed directly over a silicon solar cell. Arrays with systematically varied concentration of AgSbF6 as the salt precursor are explored. The structures are tested for their wide‐angle light capture capabilities, specifically toward enhanced conversion efficiency and current production of encapsulated solar cells. Observed are increases in the external quantum efficiency, especially at wide incident angles up to 70°, and nominal increases in the short circuit current density by 1 mA cm−2 (relative to an array without nanoparticles). Enhanced light collection is explained in terms of the beneficial effect of scattering by the nanoparticles along the waveguide cores. This is a promising approach toward solar cell encapsulants that aid to increase solar cell output over both the course of the day and year. [ABSTRACT FROM AUTHOR]

Mit der App Motion Track lassen sich durch Simulationen spielerisch Erfahrungen mit Kräften auf einen bewegten Körper machen, die zu einem Verständnis der Newtonschen Axiome beitragen können. [ABSTRACT FROM AUTHOR]

Die Android‐App Sun Locator (Lite) zeigt nicht nur per Kameraeinblendung den aktuellen Sonnen‐ und Mondstand an, sondern ermöglicht in der kostenpflichtigen Pro‐Version auch die Simulation ihres Verlaufs innerhalb eines Jahres. Zusätzlich stehen Informationen wie die aktuelle Tageslänge oder die Uhrzeit des Sonnenauf‐ und ‐untergangs zur Verfügung. Sun Locator eignet sich deshalb sowohl für praktische Anwendung wie Fotografie als auch für didaktische Zwecke. [ABSTRACT FROM AUTHOR]