bluuebunny/crossref_metadata_2025 huggingface dataset:
Whole‐volume apparent diffusion coefficient‐based entropy parameters for assessment of gastric cancer aggressiveness
Authors: Liu Song , Zheng Huanhuan , Zhang Yujuan , Chen Ling , Guan Wenxian , Guan Yue , Ge Yun , He Jian , Zhou Zhengyang
Published: May 2017

Purpose

To explore the role of whole‐volume apparent diffusion coefficient (ADC)‐based entropy parameters in the preoperative assessment of gastric cancer's aggressiveness.

Materials and Methods

In all, 64 patients with gastric cancers who underwent 3.0T magnetic resonance imaging (MRI) were retrospectively included. Regions of interest were drawn manually using in‐house software, around gastric cancer lesions on each slice of the diffusion‐weighted images and ADC maps. Entropy‐related parameters based on ADC maps were calculated automatically: (1) first‐order entropy; (2–5) second‐order entropies, including entropy(H)0, entropy(H)45, entropy(H)90, and entropy(H)135; (6) entropy(H)mean; and (7) entropy(H)range. Correlations between entropy‐related parameters and pathological characteristics were analyzed with the Spearman correlation test. The parameters were compared among different pathological characteristics with independent‐samples Kruskal–Wallis or Mann–Whitney U‐test. Additionally, diagnostic performances of parameters in differentiating different pathological characteristics were analyzed by receiver operating characteristic (ROC) curve analysis.

Results

All the entropy‐related parameters significantly correlated with T, N, and overall stages, especially the first‐order entropy (r = 0.588, 0.585, and 0.677, respectively, all P < 0.05). All the entropy‐related parameters showed significant differences in gastric cancers at different T, N, and overall stages, as well as at different status of vascular invasion (P < 0.001–0.027). And four parameters, including entropy, entropy(H)0, entropy(H)45, and entropy(H)90, showed significant differences between gastric cancers with and without perineural invasion (P 0.006–0.040).

Conclusion

Entropy‐related parameters derived from whole‐volume ADC texture analysis could help assess the aggressiveness of gastric cancers via analyzing intratumoral heterogeneity quantitatively, especially the first‐order entropy.

Level of Evidence: 2

Technical Efficacy: Stage 2

J. Magn. Reson. Imaging 2018;47:168–175.
Can Social Media Marketing Improve Customer Relationship Capabilities and Firm Performance? Dynamic Capability Perspective
Authors: Wang Zhan , Kim Hyun Gon
Published: May 2017

Social media usage has become ubiquitous, and organizations need to manage this tool to meet their strategic goals. Companies are finding it necessary to modify their approach to customer relationship management (CRM) and develop new marketing capabilities that facilitate customer satisfaction. The purpose of this study is to examine how social media usage can help firms build new CRM capabilities and thus improve marketing adoption strategies and business performance. We suggest that social CRM capability is critical when companies merge social media into their marketing strategies to improve customer engagement and firm performance. We empirically analyze data from 232 companies using Facebook, COMPUSTAT North America, and Global Fundamentals annual databases for the period 2004–2014. This study contributes to extant literature by confirming a new form of CRM capabilities – social CRM – using the resource-based view and dynamic capabilities theory frameworks, and by demonstrating that social media usage plays a moderating role by amplifying the positive impact of social CRM capabilities on firm performance.
A mixing completely scrambled system exists
Authors: BOROŃSKI JAN P. , KUPKA JIŘÍ , OPROCHA PIOTR
Published: May 2017

We prove that there exists a topologically mixing homeomorphism which is completely scrambled. We also prove that, for any integer$n\geq 1$, there is a continuum of topological dimension$n$supporting a transitive completely scrambled homeomorphism and an$n$-dimensional compactum supporting a weakly mixing completely scrambled homeomorphism. This solves a 15-year-old open problem.
Paleoecological and stratigraphic controls on eurypterid Lagerstätten: a model for preservation in the mid-Paleozoic
Authors: Vrazo Matthew B. , Brett Carlton E. , Ciurca Samuel J.
Published: May 2017

Recent studies of eurypterid paleoecology suggest that formation of eurypterid Lagerstätten in the mid-Paleozoic of Laurentia was controlled by the presence of an ecological–taphonomic window that recurred predictably in nearshore, marginal environments during transgressions. We tested this hypothesis by performing a high-resolution taxonomic, environmental, and stratigraphic survey and quantitative analysis of all Silurian–Lower Devonian eurypterid-bearing intervals in the Appalachian basin, the most prolific region for eurypterid remains in the world. Canonical correspondence analysis of sedimentological and faunal associations revealed a strong lithologic gradient between groupings of eurypterid genera and associated taxa across the basin, and a significant association of eurypterids with microbialites (thrombolites, stromatolites) and evaporitic structures. Field observations confirmed that, stratigraphically, eurypterids in the basin frequently occur above the microbialite structures and beneath evaporites and other indicators of increased salinity or subaerial exposure. Following interpretation of these features within a sequence stratigraphic framework, we present a preservational model in which (1) eurypterids inhabited nearshore settings following freshening conditions concomitant with minor transgressions, (2) their remains were subsequently buried by storms or microbialite sediment baffling, and (3) subsequent long-term preservation of tissues was facilitated by regression and cyclical shallowing-up successions that promoted hypersalinity and anoxia. In the central and southern region of the basin, where microbial structures and evidence for hypersalinity are less common, a similar pattern of cyclical shallowing-upward deposition within eurypterid-bearing units holds. Thus, eurypterid preservation appears to reflect a combination of ecological preferences and abiotic conditions that promoted inhabitation and eventual preservation within the same setting. This study provides the first quantitative support for a sea level–based control on preservation of eurypterids and adds to the growing body of evidence that suggests that analysis of exceptional preservation in the fossil record benefits from interpretation within a sequence stratigraphic framework.
German-speaking archaeology is more
Authors: Meier Thomas
Published: May 2017

In a way – as the authors admit themselves – Kerstin Hofmann's and Philipp Stockhammer's paper is very German. Most of their paper reads like a long catalogue, collecting and arranging as many recent GSA contributions to anglophone debates as the authors could find. In the end their catalogue sums up to the impressive number of around four hundred references.
Suicidality in Autistic Spectrum Disorders
Authors: Zahid Sofia , Upthegrove Rachel
Published: May 2017

Abstract. Background: It is suggested that people with autistic spectrum disorders (ASD) may be at increased risk of suicide; however, research on this topic has been minimal and there are conflicting reports in existing studies. Aim: To bring together research investigating the prevalence, risk factors, and comorbid factors of suicidality in ASD. Method: A systematic search was performed of Medline, Psych Info, Embase, and the Web of Science following PRISMA guidelines. After exclusion criteria were applied, 70 full-text articles were screened. The final review contained 12 papers with a total sample size of 2,651. Results: Prevalence of suicide attempts varied between 7% and 47%, while suicidal ideation was reported in up to 72% of cases. Being male and having a history of self-harm and depression were cited as significant risk factors. Limitations: Papers were cross sectional and contained a number of limitations. Only one paper used the gold standard for diagnosis of ASD and one a standardized measure of suicidal behavior. Conclusion: Suicidal attempts and ideation are increased in ASD; however, the extent of the increase and the risk factors identified within this group remain under-investigated. There is a lack of research on protective factors. The correlation between ASD and suicidality needs further examination with longitudinal research.
Gerald J. Wasserburg (1927–2016)
Authors: Jacobsen Stein , Papanastassiou Dimitri , DePaolo Donald
Published: May 2017

A leading geochemist who became well known for creating the first high-precision mass spectrometer, called Lunatic I, that measured isotope ratios in lunar samples from the Apollo missions.
Targeted apoptosis in ovarian cancer cells through mitochondrial dysfunction in response to Sambucus nigra agglutinin
Authors: Chowdhury Shreya Roy , Ray Upasana , Chatterjee Bishnu P , Roy Sib S
Published: May 2017

Ovarian carcinoma (OC) patients encounter the severe challenge of clinical management owing to lack of screening measures, chemoresistance and finally dearth of non-toxic therapeutics. Cancer cells deploy various defense strategies to sustain the tumor microenvironment, among which deregulated apoptosis remains a versatile promoter of cancer progression. Although recent research has focused on identifying agents capable of inducing apoptosis in cancer cells, yet molecules efficiently breaching their survival advantage are yet to be classified. Here we identify lectin, Sambucus nigra agglutinin (SNA) to exhibit selectivity towards identifying OC by virtue of its specific recognition of α-2, 6-linked sialic acids. Superficial binding of SNA to the OC cells confirm the hyper-sialylated status of the disease. Further, SNA activates the signaling pathways of AKT and ERK1/2, which eventually promotes de-phosphorylation of dynamin-related protein-1 (Drp-1). Upon its translocation to the mitochondrial fission loci Drp-1 mediates the central role of switch in the mitochondrial phenotype to attain fragmented morphology. We confirmed mitochondrial outer membrane permeabilization resulting in ROS generation and cytochrome-c release into the cytosol. SNA response resulted in an allied shift of the bioenergetics profile from Warburg phenotype to elevated mitochondrial oxidative phosphorylation, altogether highlighting the involvement of mitochondrial dysfunction in restraining cancer progression. Inability to replenish the SNA-induced energy crunch of the proliferating cancer cells on the event of perturbed respiratory outcome resulted in cell cycle arrest before G2/M phase. Our findings position SNA at a crucial juncture where it proves to be a promising candidate for impeding progression of OC. Altogether we unveil the novel aspect of identifying natural molecules harboring the inherent capability of targeting mitochondrial structural dynamics, to hold the future for developing non-toxic therapeutics for treating OC.
Subsampling scaling
Authors: Levina A. , Priesemann V.
Published: May 2017

In real-world applications, observations are often constrained to a small fraction of a system. Such spatial subsampling can be caused by the inaccessibility or the sheer size of the system, and cannot be overcome by longer sampling. Spatial subsampling can strongly bias inferences about a system’s aggregated properties. To overcome the bias, we derive analytically a subsampling scaling framework that is applicable to different observables, including distributions of neuronal avalanches, of number of people infected during an epidemic outbreak, and of node degrees. We demonstrate how to infer the correct distributions of the underlying full system, how to apply it to distinguish critical from subcritical systems, and how to disentangle subsampling and finite size effects. Lastly, we apply subsampling scaling to neuronal avalanche models and to recordings from developing neural networks. We show that only mature, but not young networks follow power-law scaling, indicating self-organization to criticality during development.
Sequencing and de novo assembly of a near complete indica rice genome
Authors: Du Huilong , Yu Ying , Ma Yanfei , Gao Qiang , Cao Yinghao , Chen Zhuo , Ma Bin , Qi Ming , Li Yan , Zhao Xianfeng , Wang Jing , Liu Kunfan , Qin Peng , Yang Xin , Zhu Lihuang , Li Shigui , Liang Chengzhi
Published: May 2017

A high-quality reference genome is critical for understanding genome structure, genetic variation and evolution of an organism. Here we report the de novo assembly of an indica rice genome Shuhui498 (R498) through the integration of single-molecule sequencing and mapping data, genetic map and fosmid sequence tags. The 390.3 Mb assembly is estimated to cover more than 99% of the R498 genome and is more continuous than the current reference genomes of japonica rice Nipponbare (MSU7) and Arabidopsis thaliana (TAIR10). We annotate high-quality protein-coding genes in R498 and identify genetic variations between R498 and Nipponbare and presence/absence variations by comparing them to 17 draft genomes in cultivated rice and its closest wild relatives. Our results demonstrate how to de novo assemble a highly contiguous and near-complete plant genome through an integrative strategy. The R498 genome will serve as a reference for the discovery of genes and structural variations in rice.
Interplay of space radiation and microgravity in DNA damage and DNA damage response
Authors: Moreno-Villanueva María , Wong Michael , Lu Tao , Zhang Ye , Wu Honglu
Published: May 2017

In space, multiple unique environmental factors, particularly microgravity and space radiation, pose constant threat to the DNA integrity of living organisms. Specifically, space radiation can cause damage to DNA directly, through the interaction of charged particles with the DNA molecules themselves, or indirectly through the production of free radicals. Although organisms have evolved strategies on Earth to confront such damage, space environmental conditions, especially microgravity, can impact DNA repair resulting in accumulation of severe DNA lesions. Ultimately these lesions, namely double strand breaks, chromosome aberrations, micronucleus formation, or mutations, can increase the risk for adverse health effects, such as cancer. How spaceflight factors affect DNA damage and the DNA damage response has been investigated since the early days of the human space program. Over the years, these experiments have been conducted either in space or using ground-based analogs. This review summarizes the evidence for DNA damage induction by space radiation and/or microgravity as well as spaceflight-related impacts on the DNA damage response. The review also discusses the conflicting results from studies aimed at addressing the question of potential synergies between microgravity and radiation with regard to DNA damage and cellular repair processes. We conclude that further experiments need to be performed in the true space environment in order to address this critical question.
DV21 decreases excitability of cortical pyramidal neurons and acts in epilepsy
Authors: Xu Min , Sun Peng , Zhang Ying , Yang Ci-Hang , Wei Xin , Ma Xiao-Xia , Yang Chong-Ren , Ni Kun-Ming , Zhang Ying-Jun , Li Xiao-Ming
Published: May 2017

Epilepsy is one of the most common neurological disorders and the administration of antiepileptic drugs (AEDs) is the most common treatment. Although there are more than 15 AEDs available, a third of epilepsy patients remain refractory to available drugs, so novel effective drugs are needed. Here, we found that DV21, which is a natural triterpenoid compound extracted from plants of the Asclepiadaceae family, significantly decreased the incidence and stages of seizures in three classical drug-induced acute seizure models in C57BL/6 mice. Furthermore, we also found that the antiepileptic effect of DV21 might be partly mediated through reducing the excitability of cortical pyramidal neurons by increasing M current, which are low-threshold non-inactivating voltage-gated potassium currents. Moreover, the application of XE991, an inhibitor of M current, could block most the antiepileptic effect of DV21. Taken together, our results indicated that DV21 might be a novel leading compound for the treatment of epilepsy.
Extracellular Vesicles Carry HIV Env and Facilitate Hiv Infection of Human Lymphoid Tissue
Authors: Arakelyan Anush , Fitzgerald Wendy , Zicari Sonia , Vanpouille Christophe , Margolis Leonid
Published: May 2017

Cells productively infected with HIV-1 release virions along with extracellular vesicles (EVs) whose biogenesis, size, and physical properties resemble those of retroviruses. Here, we found that a significant number of EVs (exosomes) released by HIV-1 infected cells carry gp120 (Env), a viral protein that mediates virus attachment and fusion to target cells, and also facilitates HIV infection in various indirect ways. Depletion of viral preparations of EVs, in particular of those that carry gp120, decreases viral infection of human lymphoid tissue ex vivo. Thus, EVs that carry Env identified in our work seem to facilitate HIV infection and therefore may constitute a new therapeutic target for antiviral strategy.
Serum Metabolomic Profiles for Breast Cancer Diagnosis, Grading and Staging by Gas Chromatography-Mass Spectrometry
Authors: Hadi Naila Irum , Jamal Qamar , Iqbal Ayesha , Shaikh Fouzia , Somroo Saleem , Musharraf Syed Ghulam
Published: May 2017

Detection of metabolic signature for breast cancer (BC) has the potential to improve patient prognosis. This study identified potentially significant metabolites differentiating between breast cancer patients and healthy controls to help in diagnosis, grading, staging and determination of neoadjuvant status. Serum was collected from 152 pre-operative breast cancer (BC) patients and 155 healthy controls in this case-controlled study. Gas chromatography-mass spectrometry (GC-MS) was used to obtain metabolic profiles followed by chemometric analysis with the identification of significantly differentiated metabolites including 7 for diagnosis, 18 for grading, 23 for staging, 15 for stage III subcategory and 10 for neoadjuvant status (p-value < 0.05). Partial Least Square Discriminant Analysis (PLS-DA) model revealed a distinct separation between healthy controls and BC patients with a sensitivity of 96% and specificity of 100% on external validation. Models for grading, staging and neoadjuvant status were built with Decision Tree Algorithm with predictive accuracy of 71.5%, 71.3% and 79.8% respectively. Pathway analysis revealed increased glycolysis, lipogenesis, and production of volatile organic metabolites indicating the metabolic alterations in breast cancer.
Presence of heterocyclic amine carcinogens in home-cooked and fast-food camel meat burgers commonly consumed in Saudi Arabia
Authors: Rizwan Khan Mohammad , Naushad Mu , Abdullah Alothman Zeid
Published: May 2017

Heterocyclic amines (HCAs) are formed by cooking protein-rich foods, for instance, meat and fish, and are listed as possible human carcinogens. In the present study, the presence of five potential HCAs (IQ, MeIQ, MeIQx, 4,8-DiMeIQx, and PhIP) in cooked camel meat burgers was analyzed for the first time. The analysis was performed in home-cooked and fast-food burger samples containing food additives. The applied cooking technique for the home-cooked samples was pan frying for a controlled cooking time and temperature. In the control cooked meat samples (samples that contained no food additives), the concentrations of MeIQx, 4,8-DiMeIQx, and PhIP ranged from 2.47 ng/g to 4.89 ng/g, whereas IQ and MeIQ were found to be below the limit of quantification. The concentrations contents of MeIQx, 4,8-DiMeIQx, and PhIP in the home-cooked and fast-food samples ranged from 1.52 ng/g to 2.13 ng/g and 1.85 ng/g to 3.46 ng/g, respectively. IQ and MeIQ were not detected in either type of sample. In comparison to the control samples, the home-cooked and fast-food samples produced lower levels of HCAs. Such observations could result from the existence of antioxidants in incorporated food additives, which induce pro-oxidative effects with the successive formation and/or scavenging of free radicals.
A simple and efficient fluorescent probe for the rapid detection of H2S in living cells and on agar gels
Authors: Li Yaqian , Gu Biao , Su Wei , Duan Xiaoli , Xu Hai , Huang Zhen , Li Haitao , Yao Shouzhuo
Published: May 2017

Herein, a simple fluorescent probe, (E)-1,3,3-trimethyl-2-(4-morpholinostyryl)-3H-indol-1-ium iodide (Mi), based on intramolecular charge transfer (ICT) was synthesized.
The reasons for the photochemical behaviour of propylamine 4-(2,4,6-triisopropylbenzoyl)benzoate during the Norrish–Yang reaction
Authors: Konieczny K. , Bąkowicz J. , Galica T. , Siedlecka R. , Turowska-Tyrk I.
Published: May 2017

Intermolecular interactions are responsible for the direction of the Norrish–Yang reaction.
Application of computational methods to the design and characterisation of porous molecular materials
Authors: Evans Jack D. , Jelfs Kim E. , Day Graeme M. , Doonan Christian J.
Published: May 2017

Composed from discrete units, porous molecular materials (PMMs) possess properties not observed for conventional, extended solids. Molecular simulations provide crucial understanding for the design and characterisation of these unique materials.
The role of metals in mammalian olfaction of low molecular weight organosulfur compounds
Authors: Block Eric , Batista Victor S. , Matsunami Hiroaki , Zhuang Hanyi , Ahmed Lucky
Published: May 2017

We highlight the role that copper and other metals play in mammalian olfaction of low molecular weight organosulfur compounds from both natural and non-natural sources.
A complex stereochemical relay approach to the antimalarial alkaloid ocimicide A1. Evidence for a structural revision
Authors: Nikolayevskiy Herman , Moe Tun Maung Kyaw , Rablen Paul R. , Ben Mamoun Choukri , Herzon Seth B.
Published: May 2017

The core structure of the potent antimalarial alkaloid ocimicide A1 was prepared by a complex stereochemical relay. Computational studies suggest a structural revision of the metabolite is necessary.
Characterization of the flavoenzyme XiaK as an N-hydroxylase and implications in indolosesquiterpene diversification
Authors: Zhang Qingbo , Li Huixian , Yu Lu , Sun Yu , Zhu Yiguang , Zhu Hanning , Zhang Liping , Li Shu-Ming , Shen Yuemao , Tian Changlin , Li Ang , Liu Hung-wen , Zhang Changsheng
Published: May 2017

Flavoenzymes are ubiquitous in biological systems and catalyze a diverse range of chemical transformations.
Miniaturised QMSIW filter using comb line with high out‐of‐band rejection
Authors: Nie Xinghe , Hong Wei
Published: May 2017

This Letter proposes a miniaturised filter that makes use of quarter‐mode substrate‐integrated waveguide (QMSIW) combining with a comb‐line architecture for the first time. The comb‐line QMSIW filter uses a periodic structure of distributed capacitance thereby reducing the size of the conventional QMSIW filter. To enhance out‐of‐band rejection, an S‐shaped slot is introduced to realise negative coupling. Using the above principles, the size of this filter is reduced by nearly half (compared with conventional QMSIW filters) while having high out‐of‐band rejection. Finally, this planar, miniaturised filter is designed and fabricated. The measured results match well with simulated results.
Analysis of dedicated and shared device‐to‐device communication in cellular networks over Nakagami‐m fading channels
Authors: Joshi Sandeep , Mallik Ranjan K.
Published: May 2017

Device‐to‐device (D2D) communication, unlike conventional cellular communication, is described as the direct communication between devices bypassing the network infrastructure. This mode of direct communication, due to its advantages, is being proposed as an integral part of the next generation cellular networks with the additional interference between the users being a challenge. In this study, the authors develop an analytical framework for a D2D‐enabled downlink cellular network with Nakagami‐m fading between the D2D communication links. The authors derive tractable expressions for the coverage probability of D2D links and cellular users, considering different propagation conditions experienced by D2D and cellular links. Using stochastic geometry, the authors provide the coverage probability analysis for the dedicated network, having orthogonal frequency resource allocation, and for the shared network, where the frequency resources are reused. Furthermore, the authors extend the coverage probability analysis to include interference‐limited dedicated and shared networks. Numerical results corroborate their analysis. The authors also derive the expressions for ergodic spectral efficiency of D2D links for both dedicated and shared networks. The results obtained are helpful in understanding the system behaviour and show the dependence of network performance on the system parameters.
Adaptive localised region and edge‐based active contour model using shape constraint and sub‐global information for uterine fibroid segmentation in ultrasound‐guided HIFU therapy
Authors: Liao Xiangyun , Yuan Zhiyong , Tong Qianqian , Zhao Jianhui , Wang Qiong
Published: May 2017

Uterine fibroids segmentation in ultrasound images is of great importance in the definition of intra‐operative planning of ultrasound‐guided high‐intensity focused ultrasound (HIFU) therapy. However, it is challenging to obtain accurate, robust and efficient uterine fibroid segmentation due to low quality of ultrasound images. In this study, the authors propose a novel adaptive localised region and edge‐based active contour model using shape constraint and sub‐global information to accurately and efficiently segment the uterine fibroids in ultrasound images with robustness against initial contour. The authors first define adaptive local radius for the localised region‐based model and combine it with the edge‐based model to accurately and efficiently capture image's heterogeneous features and edge features. Then, they incorporate a shape constraint to reduce boundary leakage or excessive contraction to obtain more accurate segmentation. To overcome the initialisation sensitivity, they introduce the sub‐global information to prevent the curve from trapping into the local minima and obtain robust results. Furthermore, the authors optimise computation by adaptively sharing local region and employing the multi‐scale segmentation method to achieve efficient segmentation. The proposed method is validated by uterine fibroid ultrasound images in HIFU therapy and the results demonstrate that it can achieve accurate, robust and efficient segmentation.
Comprehensive analysis and evaluation to unsupervised binary hashing method in image similarity measurement
Authors: Kim Jin‐Bum , Park Rae‐Hong , Kim Hong‐In
Published: May 2017

This study proposes an unsupervised binary hashing (UBH) method and provides a comprehensive analysis and evaluation to the UBH method in image similarity. Using the orthogonal locality preserving projection, the proposed UBH method performs the dimensionality reduction (DR). To reduce the quantisation error between low‐dimensional vectors and binary hash codes generated in the DR, the proposed UBH method calculates the optimal parameters of rotation and offset. The authors use two test beds to evaluate the preservation of original feature space and the semantic consistency. Experimental results with two test beds show that the proposed UBH method is state of the art.
Optimal multiple microgrids based forming of greenfield distribution network under uncertainty
Authors: Mojtahedzadeh Shahram , Ravadanegh Sajad Najafi , Haghifam Mahmoud‐Reza
Published: May 2017

Multiple microgrid (MMG) operation concept of community microgrid (MG) provides enhanced resiliency and reliability through self‐healing, enabling a high penetration of distributed generations (DGs), power interchange between MGs and real‐time communication. In this study, the methodology of optimal design of low‐voltage greenfield distribution grids based on multiple MGs in the presence of uncertainties is presented. The electrical and geographical borders of MGs community are determined using some important criteria such as power balance and spatial distribution of load. Within MGs, both of dispatchable and non‐dispatchable DGs are considered. The external grid is assumed as a backup for each MG in abnormal conditions. The proposed method determines the optimal borders of MGs, optimal size and site of DGs for each autonomous MG simultaneously. The imperialist competitive algorithm is used to optimise the total cost of optimal MG clustering problem. The method is implemented to a vacant area with residential and commercial customers. The MGs optimal service area, DGs location, size and type within each MG and LV feeder's route are indicated and compared both for deterministic and probabilistic planning cases.
One versus Two Venous Anastomoses in Microvascular Upper Extremity Reconstruction
Authors: Heine-Geldern Albrecht , Ninkovic Milomir , Broer P. , Ehrl Denis , Heidekrueger Paul
Published: May 2017

Background Free tissue transfers are routinely performed for reconstruction of the upper limb. Main complication in free flap surgery still stems from vascular compromise and many technical controversies exist regarding the technical details of how to perform the microvascular anastomosis. This study evaluates outcomes regarding the execution of one versus two venous anastomoses for upper limb reconstruction.

Methods In this study, 79 patients underwent 86 free anterolateral thigh (ALT) or groin flaps for upper limb reconstruction after trauma, infection, or malignancies. The data were retrospectively screened for patients' demographics, perioperative details, flap survival, and surgical complications. The cases were divided into two groups regarding the number of performed venous anastomoses: one versus two veins.

Results No significant differences existed between the two groups regarding preoperative comorbidities (ALT: 16 one, 21 two veins; groin: 16 one, 33 two veins). Overall, there was no significant difference regarding the rate of major (1 vein: 18.8% vs. 2 veins: 20.4%; p > 0.05) and minor (1 vein: 3.1% vs. 2 veins: 3.7%; p > 0.05) surgical complications during the 3-month follow-up period. Major complications included total flap losses of 9.4% (1 vein) versus 7.4% (2 veins) (p > 0.05).

Conclusion This study analyzed a series of microsurgical reconstructions with a focus on the impact of the number of performed venous anastomoses. The findings suggest that successful free tissue transfer for upper limb reconstruction can be achieved independent of the number of venous anastomoses. However, to promote additional safety, a second vein should be performed whenever technically possible.
Nutzenanalyse onkologischer Zentrenbildung im Bereich der Behandlung des kolorektalen Karzinoms
Authors: Weinhold Ines , Keck Tobias , Merseburger Axel , Rody Achim , Wollenberg Barbara , Wende Danny , Häckl Dennis , Elsner Christian
Published: May 2017

Hintergrund In der Behandlung des kolorektalen Karzinoms gibt es, wie bei anderen onkologischen Entitäten, den Trend einer zunehmenden Etablierung spezialisierter und zertifizierter Krebszentren. Ein Kernelement der Behandlung stellen multidisziplinäre Tumorboards dar. Eine Quantifizierung potenzieller Nutzeneffekte dieses Trends scheint vor dem Hintergrund einer zunehmend geführten Kosten-Nutzen-Diskussion wichtig und angebracht. In dieser Studie wird daher untersucht, inwiefern durch die Etablierung einer multidisziplinären Betrachtung in einem Krebszentrum das Überleben von Patienten mit der Diagnose des kolorektalen Karzinoms gesteigert werden kann. Auf dieser Grundlage werden anschließend in einem Markov-Modell epidemiologische Auswirkungen simuliert, und es wird geschätzt, welcher Nutzen unter Berücksichtigung der aktuellen demografischen Entwicklung, regional und im Zeitverlauf erwartet werden kann.

Material und Methoden Es erfolgte eine systematische Literaturanalyse zu potenziellen Überlebenseffekten in Verbindung mit einer multidisziplinären Behandlung in onkologischen Zentren im Bereich des kolorektalen Karzinoms. Nach dem PRISMA-Schema wurden aus 602 Artikeln schrittweise durch Titel-, Abstract- und Volltext-Review 10 relevante Publikationen identifiziert und in einer Metaanalyse zusammengefasst. Regionale Nutzenwirkungen, in Form gewonnener Lebensjahre, wurden am Beispiel der im Jahr 2012 (Kiel) und 2013 (Lübeck) etablierten Darmkrebszentren am Universitätsklinikum Schleswig-Holstein bis zum Jahr 2020 prognostiziert. Dafür wurde eine Simulation erwarteter Veränderungen der bis 2020 extrapolierten Inzidenz-, Mortalitäts- und Prävalenzraten in einem Markov-Modell anhand der detaillierten Bevölkerungsdaten Schleswig-Holsteins erstellt.

Ergebnisse Die Metaanalyse ergab, dass eine multidisziplinäre Fallbehandlung in Krebszenten mit einer Mortalitätsreduktion um 4,5 % assoziiert ist. Dabei profitieren insbesondere Patienten in fortgeschritteneren Krankheitsstadien. Gemäß den getroffenen Annahmen in der Simulation können durch eine multidisziplinäre Behandlung in Darmkrebszentren kumulativ 106 Lebensjahre bis 2020 in Schleswig-Holstein gewonnen werden.

Schlussfolgerung Zentrenbildung im onkologischen Bereich ist mit positiven Outcomes für Patienten verbunden. Die Literaturlage zeigt, dass weiterer Studienbedarf besteht, um weitere Auswirkungen der Zentrenbildung in der Therapie des kolorektalen Karzinoms zu untersuchen. Die Krebsregister stellen hierfür die wesentliche Grundlage dar. Auf Basis der prognostizierten epidemiologischen Entwicklung können künftige Anforderungen an die Versorgung abgeleitet werden.
Narrow-band imaging in the diagnosis of deep submucosal colorectal cancers: a systematic review and meta-analysis
Authors: Zhang Qing-Wei , Teng La-Mei , Zhang Xin-Tian , Zhang Jing-Jing , Zhou Ying , Zhou Zhi-Rui , Hou Yi-Chao , Ge Zhi-Zheng , Li Xiao-Bo
Published: May 2017

Background and aims Magnifying endoscopy with narrow-band imaging (M-NBI) has been widely used in the differential diagnosis of deep submucosal colorectal cancers (dSMCs) from superficial submucosal cancers (sSMCs) and intramucosal neoplasms. We aimed to pool the diagnostic efficacy of M-NBI and compare it with that of magnifying chromoendoscopy (M-CE) in diagnosing colorectal dSMC.

Methods PubMed, EMBASE, and the Cochrane Library were searched to identify eligible studies. Meeting abstracts were also searched. A bivariate mixed-effects binary regression model was used in the meta-analysis to calculate the pooled diagnostic efficacy of M-NBI and compare it with that of M-CE in the diagnosis of dSMC. Subgroup analyses and meta-regression were conducted to explore sources of heterogeneity.

Results We included 17 studies: 14 full texts and 3 meeting abstracts. The pooled sensitivity, specificity, and area under the summary receiver operating characteristic curve (AUC) with 95 % confidence intervals (CIs) in diagnosing dSMC were 74 % (66 % – 81 %; I2 = 84.6 %), 98 % (94 % – 99 %; I2 = 94.4 %), and 0.91 (0.88 – 0.93), respectively, for M-NBI. The pooled sensitivity, specificity and AUC (95 %CI) were 84 % (76 % – 89 %; I2 = 76.9 %), 97 % (94 % – 99 %; I2 = 90.2 %), and 0.97 (0.95 – 0.98), respectively, for M-CE. M-NBI had lower sensitivity (P < 0.01) than M-CE with similar specificity (P = 0.32). Subgroup analyses and meta-regression indicated that endoscopic diagnostic criteria, study type, endoscope type, risk of index test bias, and histopathological diagnostic criteria might be the sources of heterogeneity.

Conclusions M-NBI and M-CE had comparable specificities in diagnosing dSMC, but the sensitivity of M-NBI was slightly lower than that of M-CE.
Der Roux-Y-Magenbypass zur Therapie der Adipositas bei Jugendlichen: Analyse des Gewichtsverlaufs und des Einflusses auf Komorbiditäten im Vergleich zu adipösen Erwachsenen
Authors: Benedix Frank , Kusibab Marek , Adolf Daniela , Lorenz Eric , Wolff Stefanie , Lippert Hans , Manger Thomas , Stroh Christine
Published: May 2017

Hintergrund Die Adipositas repräsentiert eines der ernsthaftesten medizinischen Probleme unserer Zeit. Neben der Zunahme der Adipositas im Erwachsenenalter zeigt sich auch bei Jugendlichen eine besorgniserregende Entwicklung. Die bariatrische Chirurgie hat sich zu einer sicheren und effektiven Therapieoption bei Adipositas im Erwachsenenalter etabliert. Bei Jugendlichen werden diese Eingriffe noch kontrovers diskutiert. Die derzeit verfügbare Evidenz bez. Sicherheit und Effektivität ist limitiert.

Material und Methoden Im Rahmen der multizentrischen Beobachtungsstudie „Qualitätssicherung in der operativen Therapie der Adipositas“ werden seit dem 01.01.2005 die Daten von Patienten, die sich in Deutschland wegen einer Adipositas einem chirurgischen Eingriff unterzogen haben, prospektiv erfasst. Für die vorliegende Studie wurden alle Patienten berücksichtigt, bei denen im Zeitraum von 01.01.2005 bis 31.12.2014 ein primärer Roux-Y-Magenbypass (RYGB) wegen einer Adipositas durchgeführt wurde.

Ergebnisse Insgesamt wurden 370 Jugendliche (≤ 21 Jahre) und 16 840 Erwachsene untersucht. Im Jahr 2014 repräsentierte der RYGB den zweithäufigsten bariatrischen Eingriff für beide Gruppen. Bei den Jugendlichen zeigte sich ein höherer initialer BMI (49,2 vs. 47,9 kg/m2, p < 0,01), der Anteil assoziierter Nebenerkrankungen war niedriger (67,8 vs. 87,4%, p < 0,01). Die Operationsdauer (104,9 vs. 113,0 min, p < 0,01) sowie die Krankenhausverweildauer (5,2 vs. 5,9 Tage; p < 0,01) unterschieden sich signifikant zwischen beiden Gruppen. Keiner der jugendlichen Adipösen entwickelte eine Anastomoseninsuffizienz, verglichen mit einer Leckagerate von 1,6% bei den Erwachsenen (p = 0,04). Die Mortalitätsrate betrug 0,2% in der Gruppe der Erwachsenen. Keiner der adipösen Jugendlichen verstarb postoperativ. Der mittlere prozentuale Übergewichtsverlust (% EWL) war nach 12 (69,9 vs. 68,2%; p = 0,97) bzw. 24 Monaten (72,6 vs. 72,1%; p = 1,0) für beide Gruppen vergleichbar. Bei Jugendlichen mit vorbestehender arterieller Hypertonie fand sich im Vergleich zu Erwachsenen eine höhere Remissionsrate.

Schlussfolgerung Der RYGB kann bei jugendlichen Adipösen mit einer niedrigeren Morbidität und Mortalität durchgeführt werden. Trotz aller Limitierungen einer Registerstudie und der geringen Follow-up-Rate zeigt sich, dass die Ergebnisse im kurzfristigen Verlauf denen nach RYGB bei Erwachsenen mindestens vergleichbar sind. Der Fokus zukünftiger Studien muss auf der Evaluation des Langzeitverlaufs liegen.
Piezoresponse of ferroelectric films in ferroionic states: Time and voltage dynamics
Authors: Morozovska Anna N. , Eliseev Eugene A. , Morozovsky Nicholas V. , Kalinin Sergei V.
Published: May 2017

The interplay between electrochemical surface charges and bulk ferroelectricity in thin films gives rise to a continuum of coupled ferro-ionic states. These states are exquisitely sensitive to chemical and electric conditions at the surfaces, applied voltage, and oxygen pressure. Using the analytical approach combining the Ginzburg-Landau-Devonshire description of the ferroelectricity with the Langmuir adsorption isotherm for the ions at the film surface, we have studied the temperature-, time- and field-dependent polarization changes and electromechanical response of the ferro-ionic states. The responses are found to be inseparable in thermodynamic equilibrium and at low frequencies of applied voltage. The states become separable in the high frequency dynamic mode due to the several orders of magnitude difference in the relaxation times of ferroelectric polarization and surface ion charge density. These studies provide an insight into the dynamic behavior of nanoscale ferroelectrics with an open surface exposed to different kinds of the electrochemically active gaseous surrounding.
Ultrafast response of dielectric properties of monolayer phosphorene to femtosecond laser
Authors: Su Gaoshi , Wang Feng , Jiang Lan , Zhang Xiaoqin , Su Xiaoxing , Qu Liangti , Lu Yongfeng
Published: May 2017

Phosphorous consisting of only a few layers, or phosphorene, is a two-dimensional material with high carrier mobility and a useful and adjustable band gap. In this paper, we studied the ultrafast response of the dielectric properties of monolayer phosphorene to femtosecond laser pulses by employing the time-dependent density functional theory. The simulation results showed that, as a result of femtosecond laser irradiation, the dielectric function of monolayer phosphorene exhibited a negative divergence of its real part at low frequency and a remarkable “quasi-exciton” absorption peak of its imaginary part. We inferred that this type of response was induced by electron-hole pairs excited by the femtosecond laser. Moreover, we showed how the degrees of freedom (intensity and polarization) of the laser pulse could be helpful for the manipulation of the system transient response. The anisotropic dielectric response of monolayer phosphorene was also observed. Our work revealed the potential applications of monolayer phosphorene for ultrafast electronics and optoelectronics.
Deep cooling of optically trapped atoms implemented by magnetic levitation without transverse confinement
Authors: Li Chen , Zhou Tianwei , Zhai Yueyang , Xiang Jinggang , Luan Tian , Huang Qi , Yang Shifeng , Xiong Wei , Chen Xuzong
Published: May 2017

We report a setup for the deep cooling of atoms in an optical trap. The deep cooling is implemented by eliminating the influence of gravity using specially constructed magnetic coils. Compared to the conventional method of generating a magnetic levitating force, the lower trap frequency achieved in our setup provides a lower limit of temperature and more freedoms to Bose gases with a simpler solution. A final temperature as low as ∼6nK is achieved in the optical trap, and the atomic density is decreased by nearly two orders of magnitude during the second stage of evaporative cooling. This deep cooling of optically trapped atoms holds promise for many applications, such as atomic interferometers, atomic gyroscopes, and magnetometers, as well as many basic scientific research directions, such as quantum simulations and atom optics.
An integrated and multi-purpose microscope for the characterization of atomically thin optoelectronic devices
Authors: De Sanctis Adolfo , Jones Gareth F. , Townsend Nicola J. , Craciun Monica F. , Russo Saverio
Published: May 2017

Optoelectronic devices based on graphene and other two-dimensional (2D) materials, such as transition metal dichalcogenides (TMDs), are the focus of wide research interest. They can be the key to improving bandwidths in telecommunications, capacity in data storage, and new features in consumer electronics, safety devices, and medical equipment. The characterization of these emerging atomically thin materials and devices strongly relies on a set of measurements involving both optical and electronic instrumentation ranging from scanning photocurrent mapping to Raman and photoluminescence (PL) spectroscopy. Furthermore, proof-of-concept devices are usually fabricated from micro-meter size flakes, requiring microscopy techniques to characterize them. Current state-of-the-art commercial instruments offer the ability to characterize individual properties of these materials with no option for the in situ characterization of a wide enough range of complementary optical and electrical properties. Presently, the requirement to switch atomically thin materials from one system to another often radically affects the properties of these uniquely sensitive materials through atmospheric contamination. Here, we present an integrated, multi-purpose instrument dedicated to the optical and electrical characterization of devices based on 2D materials which is able to perform low frequency electrical measurements, scanning photocurrent mapping, and Raman, absorption, and PL spectroscopy in one single setup with full control over the polarization and wavelength of light. We characterize this apparatus by performing multiple measurements on graphene, transition metal dichalcogenides (TMDs), and Si. The performance and resolution of each individual measurement technique is found to be equivalent to that of commercially available instruments. Contrary to nowadays’ commercial systems, a significant advantage of the developed instrument is that for the first time the integration of a wide range of complementary optoelectronic and spectroscopy characterization techniques is demonstrated in a single compact unit. Our design offers a versatile solution to face the challenges imposed by the advent of atomically thin materials in optoelectronic devices.
Global solutions for the one-dimensional compressible Navier-Stokes-Smoluchowski system
Authors: Zhang Jianlin , Song Changming , Li Hong
Published: May 2017

In this paper, we consider a fluid-particle interaction model for the evolution of particles dispersed in a fluid. The fluid flow is governed by the Navier-Stokes equations for a compressible fluid while the evolution of the particle densities is given by the Smoluchowski equation. The coupling between the dispersed and dense phases is obtained through the drag forces that the fluid and the particles exert mutually. We establish the existence and uniqueness of a global classical solution, the existence of weak solutions, and the existence of a unique strong solution of this system in 1D for initial data ρ0 without vacuum states.
Probing the conformational behavior of the doubly substituted methyl-ethyl Criegee intermediate by FTMW spectroscopy
Authors: Cabezas Carlos , Guillemin Jean-Claude , Endo Yasuki
Published: May 2017

Four conformers of the doubly substituted methyl-ethyl Criegee intermediate, C2H5C(CH3)OO, have been observed by Fourier-transform microwave spectroscopy. The transient species was produced using a pulsed electric discharge of a gas mixture of 2,2-diiodobutane/O2. The conformational preferences differ from those observed previously for related alkyl-substituted Criegee intermediates. The observation of small splittings in the spectra due to the internal rotation of only one methyl group enabled us to determine the barrier heights of the hindered methyl rotation for the four conformers, which have been compared with those reported for other methyl-substituted Criegee intermediates.
Dynamic focusing of acoustic wave utilizing a randomly scattering lens and a single fixed transducer
Authors: Yin Jie , Tao Chao , Liu Xiaojun
Published: May 2017

In this study, we report a randomly scattering lens (RSL) coupled with a single fixed transducer to realize dynamic acoustic focusing. This acoustic lens is composed of randomly distributed acoustic scatterers, and a single ultrasound transducer is fixed on one side of the lens. Benefitting from the high-order multiple scattering in the RSL, the ultrasound emitted by the single fixed transducer can be dynamically focused onto any desired point by manipulating the transmitting waveform. Then, we successfully apply such a single channel system to decode a photoacoustic image from the received ultrasound signal. Further studies demonstrate that the focusing ability of the proposed system can be approximated by a classic acoustic lens. Its axial resolution is related to the speed of sound and the bandwidth of the signal; its lateral resolution depends not only on the ultrasound frequency but also on the numerical aperture of the RSL; furthermore, the image quality improves as the numerical aperture increases. In comparison with other acoustic focusing methods, dynamic focusing achieved by the proposed system needs neither special materials or delicate structures nor a large number of channels. Therefore, the proposed system could find broad applications ranging from medical ultrasound imaging to nondestructive detection.