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81.
82.

Being the most proliferative journal of oncology a cancer research of the past decade, the Open Access journal Oncotarget had reached more than 20,000 publications and a relatively high impact factor score in the past years. In 2018, the journal citation report decided to withdraw the status of an impact factor journal. Since there was a large discussion in the scientific community and specific reasons for the withdrawal were not stated, this bibliometric analysis was performed to assess if Oncotarget exhibits any differences in its bibliometric structure compared to other journals. For this purpose, we used the “New Quality and Quantity Indices in Sciences” platform and analyzed 20,000 Oncotarget articles. Density equalizing mapping technique helps to construct maps of cancer research in Oncotarget and shows that it has led to a unique global landscape which is not asymmetrically dominated by the Western hemisphere but exhibits a publishing architecture with a pronounced emphasis on Chinese articles.

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83.
To protect sensitive food products from oxidative deterioration, multilayer barrier film systems and also modified atmosphere packaging are widely applied. However, the preservation of food quality in such packaging systems may be compromised by the presence of defects in the sealing layer of the films, especially when these are below a critical size, typically the detection limit of standard leak testers of 10 µm. The addition of an oxygen scavenger (OS) layer in barrier film structures could therefore provide extended protection against O2 penetration through such defects. In this study, O2 absorption of different multilayer film structures including an iron‐based OS were investigated under defined gas atmospheres. Measurement cells were thereby covered with plastic films of defined O2 permeability to simulate conditions in a food package during storage with pinhole defect sizes of 10 and 17 µm. The results indicated that the OS film structures applied could only compensate for a defect size of 10 µm in the sealing layer. Analysis of the O2 absorption of different multilayer film structures at 85% and 100% relative humidity showed that higher humidity accelerates the activation of the scavenger. After full activation, the scavenger kinetics are the same for 85% and 100% relative humidity. Long‐term storage experiments using the most effective film structure from the preliminary experiments were carried out to compare O2 absorption of a snack food product in packages with and without an OS. The analyzed linear gradient of the reaction of the OS film and food product, respectively, indicated first‐order reaction kinetics with corresponding reaction constants calculated to be K (food product) 0.021 mg (O2) mbar (O2)?1 day?1 and K (OS film) 0.066 mg (O2) mbar (O2)?1 day?1. The reaction velocity of the OS was thus three times faster than that of the food. The applicability of OS multilayer film systems to compensate a critical pinhole defect size of 10 µm for sensitive food products could therefore be confirmed. The measurement of quality parameters for the status of lipid oxidation processes would help to verify this result. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
84.
Two InP‐based III–V semiconductor etching recipes are presented for fabrication of on‐chip laser photonic devices. Using inductively coupled plasma system with a methane free gas chemistry of chlorine and nitrogen at a high substrate temperature of 250 °C, high aspect ratio, anisotropic InP‐based nano‐structures are etched. Scanning electron microscopy images show vertical sidewall profile of 90° ± 3°, with aspect ratio as high as 10. Atomic Force microscopy measures a smooth sidewall roughness root‐mean‐square of 2.60 nm over a 3 × 3 μm scan area. The smallest feature size etched in this work is a nano‐ring with inner diameter of 240 nm. The etching recipe and critical factors such as chamber pressure and the carrier plate effect are discussed. The second recipe is of low temperature (?10 °C) using Cl2 and BCl3 chemistry. This recipe is useful for etching large areas of III–V to reveal the underlying substrate. The availability of these two recipes has created a flexible III–V etching platform for fabrication of on‐chip laser photonic devices. As an application example, anisotropic InP‐based waveguides of 3 μm width are fabricated using the Cl2 and N2 etch recipe and waveguide loss of 4.5 dB mm?1 is obtained.
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85.
Microfibers produced with electrospinning have recently been used in tissue engineering. In the development of artificial implants for nerve regeneration they are of particular interest as guidance structures for cell migration and axonal growth. Using electrospinning we produced parallel-orientated biocompatible fibers in the submicron range consisting of poly(ε-caprolactone) (PCL) and star shaped NCO-poly(ethylene glycol)-stat-poly(propylene glycol) (sPEG). Addition of the bioactive peptide sequence glycine-arginine-glycine-aspartate-serine (GRGDS) or the extracellular matrix protein fibronectin to the electrospinning solution resulted in functionalized fibers. Surface characteristics and biological properties of functionalized and non-functionalised fibers were investigated. Polymer solutions and electrospinning process parameters were varied to obtain high quality orientated fibers. A polymer mixture containing high molecular weight PCL, PCL-diol, and sPEG permitted a chemical reaction between hydroxyl groups of the diol and isocyanante groups of the sPEG. Surface analysis demonstrated that sPEG at the fiber surface minimized protein adhesion. In vitro experiments using dorsal root ganglia explants showed that the cell repellent property of pure PCL/sPEG fibers was overcome by functionalization either with GRGDS peptide or fibronectin. In this way cell migration and axonal outgrowth along fibers were significantly increased. Thus, functionalized electrospun PCL/sPEG fibers, while preventing non-specific protein adsorption, are a suitable substrate for biological and medical applications.  相似文献   
86.
This research uses two different measurement operations to examine contemporary stereotypes of Asians, Blacks, and Whites held by an ethnically diverse sample of teachers. Data were drawn from a sample of 188 teachers representing over 160 schools in Southern California. Consistent with previous research, participants endorsed a "model minority" stereotype of Asians with regard to intelligence, academic striving, introversion, and rule compliance. Contrary to expectation, there was substantial congruence in the degree of uniformity and favorableness of the stereotypic traits associated with Blacks and Whites, with participants' revealing both strong positive and negative trait associations. The use of both open-ended and fixed-format measurement strategies revealed some method variation in the assessment of participants racial beliefs, with the open-ended format suggesting more complex and heterogeneous racial representations. Results are discussed in terms of methodological issues in stereotype assessment and implications for reducing the impact of racial biases in psychoeducational evaluations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
87.
Journal of Materials Science - Electrical properties of beryllium-alumino-tellurite glasses and glass–ceramics doped with iron ions were studied using impedance spectroscopy. The conductivity...  相似文献   
88.
A tubular micromotor with spatially resolved compartments is presented toward efficient site-specific cargo delivery, with a back-end zinc (Zn) propellant engine segment and an upfront cargo-loaded gelatin segment further protected by a pH-responsive cap. The multicompartment micromotors display strong gastric-powered propulsion with tunable lifetime depending on the Zn segment length. Such propulsion significantly enhances the motor distribution and retention in the gastric tissues, by pushing and impinging the front-end cargo segment onto the stomach wall. Once the micromotor penetrates the gastric mucosa (pH ≥ 6.0), its pH-responsive cap dissolves, promoting the autonomous localized cargo release. The fabrication process, physicochemical properties, and propulsion behavior are systematically tested and discussed. Using a mouse model, the multicompartment motors, loaded with a model cargo, demonstrate a homogeneous cargo distribution along with approximately four-fold enhanced retention in the gastric lining compared to monocompartment motors, while showing no apparent toxicity. Therapeutic payloads can also be loaded into the pH-responsive cap, in addition to the gelatin-based compartment, leading to concurrent delivery and sequential release of dual cargos toward combinatorial therapy. Overall, this multicompartment micromotor system provides unique features and advantages that will further advance the development of synthetic micromotors for active transport and localized delivery of biomedical cargos.  相似文献   
89.
Developed an additive model to account for reading times for 2 different reading tasks (reading for retention and reading for comprehension). The reading strategies of 48 college students and 64 5th graders and individual differences between fast and slow readers were examined. Ss were assumed to have processors that handle the lexical, structural, and meaning information in sentences. The various task, age, and reading speed groups were hypothesized to use the 3 processors for differing amounts of time. The model was supported by word-by-word reading times for 80 sentences and by 9 empirical indices of lexical, structural, and meaning attributes of text. Results show that for skilled adult Ss, relatively more time was spent processing structure in the retention task, and meaning in the comprehension task. Fifth graders had not fully mastered the connection between task demands and linguistic processors shown by adults, and thus used mixtures of the adult strategies. (101 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
90.
Proposes a model to explain the transitions experienced by training directors during an internship year. Six transitions are identified, including courting, bonding, rapprochement, mentoring, launching, and reunion, and the particular behaviors and events that signal each passage are described. These transitions are contrasted with those often experienced by interns. (32 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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