bluuebunny/crossref_metadata_2025_split huggingface dataset:
Processing‐structure‐property relationships in solid‐state shear pulverization: Parametric study of specific energy
Authors: Brunner Philip J. , Clark Joshua T. , Torkelson John M. , Wakabayashi Katsuyuki 
Published: March 2012

AbstractSolid‐state shear pulverization (SSSP) is a unique processing technique for mechanochemical modification of polymers, compatibilization of polymer blends, and exfoliation and dispersion of fillers in polymer nanocomposites. A systematic parametric study of the SSSP technique is conducted to elucidate the detailed mechanism of the process and establish the basis for a range of current and future operation scenarios. Using neat, single component polypropylene (PP) as the model material, we varied machine type, screw design, and feed rate to achieve a range of shear and compression applied to the material, which can be quantified through specific energy input (Ep). As a universal processing variable, Ep reflects the level of chain scission occurring in the material, which correlates well to the extent of the physical property changes of the processed PP. Additionally, we compared the operating cost estimates of SSSP and conventional twin screw extrusion to determine the practical viability of SSSP. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers
Influence of the degree of exfoliation on the thermal conductivity of polypropylene nanocomposites
Authors: Laske Stephan , Duretek Ivica , Witschnigg Andreas , Mattausch Hannelore , Tscharnuter Daniel , Holzer Clemens 
Published: March 2012

AbstractThe aim of this study was to determine the influence of exfoliated silicate layers on the thermal conductivity of polypropylene nanocomposites. The correlation of thermal conductivity with the degree of exfoliation is examined and compared to common mineral fillers like talcum. The results clearly show that not only the filler content but also the size and number of the main particles (specific surface) influence thermal conductivity significantly. With respect to this, the smaller the particles and the more particles are in the matrix, the higher the increase in thermal conductivity. Compared to common fillers, the increase in thermal conductivity is considerably higher with exfoliated layered silicates and directly depends on the degree of exfoliation. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers
Phosphorus gettering of iron by screen‐printed emitters in monocrystalline Czochralski silicon wafers
Authors: Pletzer Tobias M. , Suckow Stephan , Stegemann Elmar F. R. , Windgassen Horst , Bätzner Derk L. , Kurz Heinrich 
Published: March 2012

ABSTRACTIn this paper, we demonstrate single‐sided screen‐printed emitters in thin monocrystalline Czochralski silicon (Cz‐Si) wafers with an improved gettering of iron compared with conventional double‐sided POCl3 emitters. The phosphorus dopant pastes used have to be chosen carefully to provide a sufficiently low emitter sheet resistance and to avoid iron contamination. The iron concentration is determined in a non‐destructive way from the minority carrier lifetime obtained by quasi‐steady‐state photoconductance measurements, down to levels not yet demonstrated for screen‐printed emitters. In addition, the well‐known metastable boron–oxygen complexes in Cz‐Si have been transferred into a stable state by light‐induced degradation prior to these measurements. Copyright © 2012 John Wiley & Sons, Ltd.
Back‐contacted back‐junction n‐type silicon solar cells featuring an insulating thin film for decoupling charge carrier collection and metallization geometry
Authors: Reichel Christian , Granek Filip , Hermle Martin , Glunz Stefan W. 
Published: March 2012

ABSTRACTIn this study, back‐contacted back‐junction n‐type silicon solar cells featuring a large emitter coverage (point‐like base contacts), a small emitter coverage (point‐like base and emitter contacts), and interdigitated metal fingers have been fabricated and analyzed. For both solar cell designs, a significant reduction of electrical shading losses caused by an increased recombination in the non‐collecting base area on the rear side was obtained. Because the solar cell designs are characterized by an overlap of the B‐doped emitter and the P‐doped base with metal fingers of the other polarity, insulating thin films with excellent electrical insulation properties are required to prevent shunting in these overlapping regions. Thus, with insulating thin films, the geometry of the minority charge carrier collecting emitter diffusion and the geometry of the interdigitated metal fingers can be decoupled. In this regard, plasma‐enhanced chemical vapor deposited SiO2 insulating thin films with various thicknesses and deposited at different temperatures have been investigated in more detail by metal‐insulator‐semiconductor structures. Furthermore, the influence of different metal layers on the insulation properties of the films has been analyzed. It has been found that by applying a SiO2 insulating thin film with a thickness of more than 1000 nm and deposited at 350 °C to solar cells fabricated on 1 Ω cm and 10 Ω cm n‐type float‐zone grown silicon substrates, electrical shading losses could be reduced considerably, resulting in excellent short‐circuit current densities of more than 41 mA/cm2 and conversion efficiencies of up to 23.0%. Copyright © 2012 John Wiley & Sons, Ltd.
Development and validation of a measurement tool to assess perceptions of palliative care
Authors: Milne Donna , Aranda Sanchia , Jefford Michael , Schofield Penelope 
Published: March 2012

AbstractObjectivesUnderstanding patient's perceptions about palliative care is necessary to make an effective referral. The aim was to develop and validate a measure of patient perceptions.MethodsItems were generated through patient, family caregiver and health professional interviews. The Perceptions of Palliative Care Instrument (PPCI) was administered to 85 patients with advanced cancer (AC). A subset (n = 39) completed it 7 days later. Participants also completed the Palliative Care Outcome Scale (POS), the Edmonton Symptom Assessment Scale (ESAS) and the Distress Thermometer (DT) for validation purposes.ResultsFactor analysis revealed four domains (positive and negative emotional and cognitive reactions to palliative care, emotional and practical palliative care needs and perceptions of health) and eight subscales with factor loadings for all items above 0.51, explaining 61–81% of the total variance. Reliability analyses revealed high internal consistency (Cronbach's alpha coefficients >0.76). Intraclass correlation coefficients showed moderate to strong correlations between time points indicating stability over time. All POS items correlated with two or more dimensions of the PPCI (allr > 0.30); ESAS total distress correlated positively with the palliative care needs domain and the DT with needs and perceived burden (allr > 0.30).ConclusionsThe PPCI is a four‐factor, 37‐item measure that assesses perceptions of palliative care held by patients with AC. The measure has good internal consistency, test–retest reliability and convergent validity. Copyright © 2012 John Wiley & Sons, Ltd.
Social cognitive influences on physical activity participation in long‐term breast cancer survivors
Authors: Phillips Siobhan M. , McAuley Edward 
Published: March 2012

AbstractBackgroundAlthough physical activity is beneficial for breast cancer survivors, the majority do not meet public health physical activity recommendations. The purpose of this study was to test a social cognitive theory model of physical activity behavior in a sample of long‐term breast cancer survivors using both self‐report and objective measures of physical activity.MethodsParticipants (N = 1527) completed measures of physical activity, self‐efficacy, goals, outcome expectations, fatigue, and social support at baseline and 6‐month follow‐up. A subsample (n = 370) was randomly selected to wear an accelerometer. It was hypothesized that self‐efficacy directly and indirectly influences physical activity through goals, social support, fatigue, and outcome expectations. Relationships were examined using panel analysis within a covariance modeling framework.ResultsThe hypothesized model provided a good model‐data fit (χ2 = 1168.73, df = 271,p = <0.001, CFI = 0.96, SRMR = 0.04) in the full sample when controlling for covariates. At baseline, self‐efficacy directly and indirectly, via goals, outcome expectations, and social support, influenced physical activity. These relationships were also supported across time. Additionally, the hypothesized model was supported in the subsample with accelerometer data (χ2 = 656.88, df = 330,p < 0.001, CFI = 0.95, SRMR = 0.05).ConclusionsThis study validates a social cognitive model for understanding physical activity behavior in long‐term breast cancer survivors. Future studies should be designed to replicate this model in other breast cancer survivor populations, and the findings should be applied to the development of future physical activity programs and studies for this population. Copyright © 2012 John Wiley & Sons, Ltd.
Laboratory characterization of metal‐oxide sensors intended for in situ analyses of pheromones – SOMMSA approach
Authors: Wehrenfennig Christoph , Schott Matthias , Gasch Tina , Sauerwald Tilman , Düring Rolf‐Alexander , Vilcinskas Andreas , Kohl Claus‐Dieter 
Published: March 2012

AbstractWe present pheromone measurements of metal‐oxide gas sensors in a laboratory setup using a ‘selective odorant measurement of a multi‐sensor array’. The array was equipped with commercial gas sensors and measured with constant temperatures and a temperature cycle to increase the sensitivity. To compare and to calibrate the measurement of insect pheromones, we used a portable GC‐MS with an electro‐antennographic detection system for insect antennae. In order to reach a proof of principles for the intended use of the system for in situ analyses in viticulture and the development of a portable biosensor, we tested the sensors with the main component E7,Z9‐Dodecadien‐1‐yl acetate of the pheromone of the grapevine moth (Lobesia botrana).
Efficient Functional Delivery of siRNA using Mesoporous Silica Nanoparticles with Ultralarge Pores
Authors: Na Hee‐Kyung , Kim Mi‐Hee , Park Kihyun , Ryoo Soo‐Ryoon , Lee Kyung Eun , Jeon Hyesung , Ryoo Ryong , Hyeon Changbong , Min Dal‐Hee 
Published: March 2012

AbstractAmong various nanoparticles, mesoporous silica nanoparticles (MSNs) have attracted extensive attention for developing efficient drug‐delivery systems, mostly due to their high porosity and biocompatibility. However, due to the small pore size, generally below 5 nm in diameter, potential drugs that are loaded into the pore have been limited to small molecules. Herein, a small interfering RNA (siRNA) delivery strategy based on MSNs possessing pores with an average diameter of 23 nm is presented. The siRNA is regarded as a powerful gene therapeutic agent for treatment of a wide range of diseases by enabling post‐transcriptional gene silencing, so‐called RNA interference. Highly efficient, sequence‐specific, and technically very simple target gene knockdown is demonstrated using MSNs with ultralarge pores of size 23 nm in vitro and in vivo without notable cytotoxicity.
Granum‐Like Stacking Structures with TiO2–Graphene Nanosheets for Improving Photo‐electric Conversion
Authors: Yang Nailiang , Zhang Yu , Halpert Jonathan E. , Zhai Jin , Wang Dan , Jiang Lei 
Published: March 2012

AbstractSolar energy is commonly considered to be one of the most important forms of future energy production. This is due to its ability to generate essentially free power, after installation, with low environmental impact. Green plants, meanwhile, exhibit a process for light‐to‐charge conversion that provides a useful model for using solar radiation efficiently. Granum, the core organ in photosynthesis consists of a stack of ~10–100 thylakoids containing pigments and electrons acceptors. Imitating the structure and function of granum, stacked structures are fabricated with TiO2/graphene nanosheets as the thylakoids unit, and their photo‐electric effect is studied by varying the number of layers present in the film. The photo‐electric response of the graphene composites are found to be 20 times higher than that of pure TiO2 in films with 25 units stacked. Importantly, the cathodic photocurrent changes to anodic photocurrent as the thickness increases, an important feature of efficient solar cells which is often ignored. Here graphene is proposed to perform similarly to the b6f complex in granum, by separating charges and transporting electrons through the stacked film. Using this innovation, stacked TiO2/graphene structures are now able to significantly increase photoanode thickness in solar cells without losing the ability to conduct electrons.
End‐to‐end performance of transmit antenna selection and generalized selection combining in dual‐hop amplify‐and‐forward relay network in the presence of feedback errors
Authors: Yılmaz Ahmet , Kucur Oğuz 
Published: March 2012

ABSTRACTIn this paper, end‐to‐end performance of transmit antenna selection (TAS) and generalized selection combining (GSC) is studied in a dual‐hop amplify‐and‐forward relay network over flat Rayleigh fading channels. In the system, source and destination equipped with multiple antennas, communicate by the help of single relay equipped with single antenna. Source‐destination link is not available. TAS is used for transmission at the source, and GSC is used for reception at the destination. By considering the relay location and the presence of error in feedback channel from the relay to the source, we derive closed‐form outage probability, moment generating function and moments of end‐to‐end signal‐to‐noise ratio, and closed‐form symbol error probability (SEP) expressions for channel state information (CSI)‐based and fixed relay gains. The diversity order and array gain of the network are obtained for both CSI‐based and fixed relay gains by deriving asymptotical outage probability and SEP expressions. The analytical results are validated by the Monte Carlo simulations. Copyright © 2012 John Wiley & Sons, Ltd.
Carbon sequestration potential of parkland agroforestry in the Sahel
Authors: Luedeling Eike , Neufeldt Henry 
Published: March 2012

Abstract
Establishing parkland agroforestry on currently treeless cropland in the West African Sahel may help mitigate climate change. To evaluate its potential, we used climatically suitable ranges for parklands for 19 climate scenarios, derived by ecological niche modeling, for estimating potential carbon stocks in parkland and treeless cropland. A biocarbon business model was used to evaluate profitability of hypothetical Terrestrial Carbon Projects (TCPs), across a range of farm sizes, farm numbers, carbon prices and benefit sharing mechanisms. Using climate analogues, we explored potential climate change trajectories for selected locations. If mature parklands covered their maximum range, carbon stocks in Sahelian productive land would be about 1,284 Tg, compared to 725 Tg in a treeless scenario. Due to slow increase rates of total system carbon by 0.4 Mg C ha−1 a−1, most TCPs at carbon prices that seem realistic today were not feasible, or required the participation of large numbers of farmers. For small farms, few TCP scenarios were feasible, and low Net Present Values for farmers made it unlikely that carbon payments would motivate many to participate in TCPs, unless additional benefits were provided. Climate analogue locations indicated an uncertain climate trajectory for the Sahel, but most scenarios projected increasing aridity and reduced suitability for parklands. The potentially severe impacts of climate change on Sahelian ecosystems and the uncertain profitability of TCPs make the Sahel highly risky for carbon investments. Given the likelihood of degrading environmental conditions, the search for appropriate adaptation strategies should take precedence over promoting mitigation activities.
Management of Digital Tendon Avulsion at the Musculotendinous Junction of the Forearm: A Systematic Review
Authors: Collins Jessica , Ishihara Yoshihiro , Thoma Achilleas 
Published: March 2012

Background Tendon avulsion at the musculotendinous junction caused by digit avulsion amputation or closed injury is a challenging problem, for which the literature lacks definitive recommendations regarding treatment. We have provided a systematic review and developed an algorithm to delineate optimal management of this injury. Methods Two independent reviewers undertook a systematic review of the literature to identify articles discussing management of forearm tendons avulsed at their musculotendinous junction. Patient demographics, injury mechanism, injury pattern, type of repair, and outcome were investigated. These data were analyzed to reveal tendencies in management, which were then organized into an algorithm. Results Twenty articles fit our criteria for a total of 91 tendons. Cases were mostly males involved in work accidents. Treatment options were tendon resection, reattachment to muscle, tendon transfer, and side-to-side repair. When the digit was replanted, tendons avulsed through avulsion amputations were preferentially treated by reattachment in the case of the thumb, transfers for the index and long fingers, and resection for the ring and small fingers. Reattachment was favored for metacarpophalangeal level amputations, while transfer was selected for proximal phalanx levels. For closed avulsion injuries, flexors were preferentially treated with reattachment or transfer, while extensors underwent transfer or side-to-side repair. Conclusions In the management of tendon avulsions at the musculotendinous junction, specific procedures are favored depending on the mechanism of injury, the type of tendon and digit involved, and the level of bone amputation. An algorithm is presented to facilitate optimal treatment based on these injury characteristics.
Can Computed Tomographic Gastrography and Multiplanar Reformatting Aid the Laparoscopic Surgeon in Planning a Gastric Resection? A Pictorial Essay
Authors: Zalev Arthur H. , Grantcharov Teodor , Deitel Wayne 
Published: March 2012

Purpose To assess the value and feasibility of computed tomographic gastrography and multiplanar reformatting in the preoperative evaluation of patients undergoing laparoscopic gastric resection. Materials and Methods Fourteen patients with gastric lesions were included in the study. A supine scan was performed after a hypotonic drug, an effervescent agent, and intravenous contrast. This was followed by delayed prone and decubitus scans. We created multiplanar reformats, transparency rendered images, and endoluminal images. The tumours were localized, and distances were measured to the esophagogastric junction and the pylorus. Results Eleven patients underwent resections. Seven had laparoscopic wedge resections for aberrant pancreas (1 patient), carcinoid (1), Castleman disease (1), and gastrointestinal stromal tumours (GISTs) (4). One patient had an open subtotal gastrectomy for carcinoma due to adhesions. One had a hand-assisted sleeve resection for a gastrointestinal stromal tumour. Two had hand-assisted total gastrectomies for carcinoma and a GIST. For surgical planning, the surgeon rated the imaging extremely useful in 7 and useful in 4. Imaging was extremely useful or useful to localize laparoscopically invisible tumours in 6 patients and to relate tumours to the esophagogastric junction or pylorus and to assess localized vs extensive resection in 8. Correlation was excellent between the preoperative imaging and the intraoperative findings. Conclusions Computed tomographic gastrography and multiplanar reformatting are useful aids in preoperative planning of laparoscopic gastric resections.
Down‐regulated expression of family with sequence similarity 3, member B (FAM3B), in oral squamous cell carcinoma
Authors: Shiiba Masashi , Ishige Shunsaku , Saito Yasuhiro , Shimizub Toshihiro , Minakawa Yasuyuki , Kasamatsu Atsushi , Ogawara Katsunori , Uzawa Katsuhiro , Tanzawa Hideki 
Published: March 2012

AbstractPurpose: Family with sequence similarity 3, member B (FAM3B), also known as PANcreatic DERived factor (PANDER), is an islet‐specific cytokine predominantly expressed in both pancreatic α‐ and β‐cells. FAM3B is known to induce apoptosis in pancreatic cells, and may therefore be able to regulate apoptosis in other cell types, including cancer cells. However, the role of FAM3B in carcinogenesis is unknown. We previously performed global gene screening using DNA microarray analysis to identify crucial molecules in oral squamous cell carcinoma (OSCC). The results showed significant down‐regulation of FAM3B in OSCC‐derived cell lines, as compared with human normal oral keratinocytes (HNOKs). The aim of the present study was to clarify the association between FAM3B and OSCCs.Results: Expression profiles of FAM3B in OSCC‐derived cell lines and human primary OSCCs were examined by real‐time quantitative reverse transcriptase‐polymerase chain reaction and Western blot analysis. Significantly decreased expression of FAM3B mRNA and FAM3B protein were observed in five OSCC‐derived cell lines, as compared with HNOKs. Moreover, immunohistochemical analysis revealed down‐regulated FAM3B protein expression in primary OSCC samples. In order to examine whether microRNA (miRNA) potentially regulates FAM3B expression, miRNA microarray analysis was performed with OSCC‐derived cell lines. miRNA microarray data showed that miR‐181a, miR‐181b, miR‐200b, and miR‐200c, which can induce imperfect base pairing with the 3′‐untranslated region of FAM3B mRNA, were up‐regulated in all cell lines examined.Conclusions: These results indicate that decreased FAM3B expression is able to promote OSCC progression and that certain miRNAs may be correlated with the altered expression of FAM3B.
Where do small, weakly inertial particles go in a turbulent flow?
Authors: Gibert Mathieu , Xu Haitao , Bodenschatz Eberhard 
Published: March 2012

AbstractWe report experimental results on the dynamics of heavy particles of the size of the Kolmogorov scale in a fully developed turbulent flow. The mixed Eulerian structure function of two-particle velocity and acceleration difference vectors $\langle {\delta }_{r} \mathbi{v}\boldsymbol{\cdot} {\delta }_{r} {\mathbi{a}}_{\mathbi{p}} \rangle $ was observed to increase significantly with particle inertia for identical flow conditions. We show that this increase is related to a preferential alignment between these dynamical quantities. With increasing particle density the probability for those two vectors to be collinear was observed to grow. We show that these results are consistent with the preferential sampling of strain-dominated regions by inertial particles.