bluuebunny/crossref_metadata_2025_split huggingface dataset:
Shrinkage controlled pastes for bulky silver and copper thick films in power electronics
Authors: Schmidt Richard , Reinhardt Kathrin , Seuthe Thomas , Schwab Olga , Feller Claudia , Eberstein Markus 
Published: November 2015

Harvesting green energy and sustainable, effective use of it is based on efficient, cost-effective power electronics. To build robust, multi-functional and highly integrated electronic modules, metallizations with low resistances and the capability to carry high current loads for inner and top layer thick-films are needed. Additionally, these layers have to be interconnectable by metallized vias, soldering and bonding.
A major challenge in realization of bulky silver and copper thick-films is to allow sufficient evaporation of the gaseous products during the interface reaction. Various ways to attain evaporation possibilities via controlled shrinkage retardation of the thick metal film are examined.
The influence of composition of the used solids, their grain size distributions and the use of miscellenaous organic vehicles were examined in several research projects by variation of glass amount, particle size, shrinkage measurements as well as microstructure and film properties.
Through partial retardation, a thick printing copper paste for 300 μm and a pure silver paste for 100 μm metallizations could be realized. By use of suited additives, the film shrinkage could be almost completely constrained which allowed the development of non-shrinking via-fill pastes.
Wedge Bond Process Optimization Method for 1.5 mil Al Wire on Al Bond Pad
Authors: Qi Wenjuan , Evans Daniel D. 
Published: November 2015

Modern wedge bonders have evolved since their early inception in 1957. This paper will review the common challenges process engineers face when selecting a wedge bond machine configuration and developing robust processes. Wedge bond cases presented will show the tradeoff between process inputs and the resulting bond shapes, bond appearance of black ring, burrs, pull results, etc.
The purpose of this work was to optimize the process outputs: bond shape, black ring, burrs, and pulls on a die with aluminum bond pads. Process inputs included Force, Time, and Ultrasonic Level. An aluminum wafer was used to understand the basic relationship between process parameter inputs and outputs. The learning was then applied to a die with aluminum bond pads. Examples of non-compliance and compliance will be shown to help process engineers evaluate wedge bonds and make refinements.
The case studied was for an aluminum bond pad/Al wafer and 1.5 mil aluminum wire interaction that creates burrs around the bond (wire to pad interface), black ring on the bond periphery (wedge tool to wire interface) and the resulting pulls. Both the graphical and numerical results of the case study have clearly demonstrated the relationship between the typical process inputs and outputs, particularly bond shape, burrs, black ring and pulls. The findings in this study will provide a general guideline and a troubleshooting reference for wedge bonding process development.
RF and Microwave Power Amplifiers assembly – Interaction between materials, design and process on reliability
Authors: Nguty Tennyson , Plata Tyrone , Thoonen Henk 
Published: November 2015

The demand for data anywhere and at anytime (mobile internet) is putting increasing pressure on network operators in their deployment of wireless communication infrastructure. This has pushed upwards across the supply chain, from suppliers to customers. At the core of the infrastucture are RF power amplifiers (PA) with very costly design, hence important to get it right first time. Thermo-mechanical compliance are key attributes to consistent product performance and reliability amidst stringent mission profiles.
Most transistor component manufacturers focus on their core competence – component design. Network operators on the other hand focus on the PA design. In most cases, the assembly of the PA module is an after-thought and a key enabler. These transistors are usually high power devices (&gt; 100 watts), hence demanding excellent thermal management. The packages used have a metal flange in addition to RF/DC leads which are soldered in the PA module. These act as a heat spreader and electrical interconnect which affects the product performance. Since these interconnects are in different planes, assembly requires heatsinks with cavities (flange soldering).
The main challenge being tackled in this study is the response of the materials being soldered in a different plane – leads to board and flange to heatsink interface. This is why proper soldering of the transitors (flange & leads) is an essential part in PA assembly due to the impact on module performance & reliability. To achieve the desired thermal and reliability requirements, a variety of factors are critical including the cavity design, solder and reflow soldering process. In this paper, these factors are evaluated via both thermo-mechanical simulations and experimental work. Since there are lots of materials with different properties involved in the assembly, it is vital to evaluate its behavior prior to the actual process evaluation as it has impact on cost and timing effectiveness of the study. These simulations are used as initial indication for trends which are later validated by experimental evaluations. The thermal impedance (Rth) in combination to acoustic microscopy / x-rays is used to assess the soldered flange during assembly & reliability.
Outcomes of Take-Back Operations in Breast Reconstruction with Free Lower Abdominal Flaps
Authors: Yim Ji Hong , Yun Jiyoung , Lee Taik Jong , Kim Eun Key , Cho Jonghan , Eom Jin Sup 
Published: November 2015

Background Microvascular complications after free-flap breast reconstructions are potentially devastating problems that can increase patient morbidity and lead to flap loss. To date, no comprehensive study has examined the rates of salvage and the methods of microvascular revision in breast reconstruction. We reviewed the treatment of microvascular complications of free-flap breast reconstruction procedures over a seven-year period.
Methods A retrospective review of all patients who underwent microvascular breast reconstruction at our institution between April 2006 and December 2013 was conducted. Based on their surgical records, all patients who required emergency re-exploration were identified, the rate of flap salvage was determined, the factors associated with flap salvage were evaluated, and the causes and methods of revision were reviewed.
Results During the review period, 605 breast reconstruction procedures with a free lower abdominal flap were performed. Seventeen of these flaps were compromised by microvascular complications, and three flaps were lost. The overall salvage rate was 82.35%. No significant differences between the salvaged group and the failed group were observed with regard to age, BMI, axillary dissection, number of anastomotic arteries and veins, recipient vessel types, or use of the superficial inferior epigastric vein in the revision operation. Successful salvage of the flap was associated with a shorter time period between recognizing the signs of flap compromise and the take-back operation.
Conclusions The salvage rate of compromised lower abdominal flaps was high enough to warrant attempting re-exploration. Immediate intervention after the onset of flap compromise signs is as important as vigilant postoperative monitoring.
Anatomic Differences in the Sacral Hiatus During Caudal Epidural Injection Using Ultrasound Guidance
Authors: Park Gi-young , Kwon Dong Rak , Cho Hee Kyung 
Published: November 2015

ObjectivesThe aim of this study was to clarify differences in the anatomic structure of the sacral hiatus and angle of needle insertion during caudal epidural steroid injection using ultrasound guidance in patients according to sex and age.MethodsA total of 237 patients with low back pain with or without sciatica were included. Sonograms of the sacral hiatus were obtained, and caudal epidural steroid injection using ultrasound guidance was performed in all patients. The intercornual distance, diameter of the sacral canal, thickness of the sacrococcygeal ligament, optimal angle for needle insertion, and actual angle of needle insertion were measured.ResultsBetween men and women, significant differences were observed for the intercornual distance (17.7 versus 16.5 mm; P< .01) and thickness of the sacrococcygeal ligament (4.3 versus 3.9 mm; P = .02). In all patients, the thickness of the sacrococcygeal ligament (r= 0.28) and diameter of the sacral canal (r= 0.40) were positively correlated with the optimal angle for needle insertion (P < .01). In women, the thickness of the sacrococcygeal ligament (r = −0.24), diameter of the sacral canal (r = −0.27), optimal angle for needle insertion (r = −0.29), and actual angle of needle insertion (r = −0.18) were negatively correlated with age. In men, only the diameter of the sacral canal was negatively correlated with age (r = −0.30).ConclusionsWe found that the sacral hiatus has anatomic differences between patients of different sexes and ages. Understanding these differences, especially in women, may improve the safety and reliability of caudal epidural steroid injection.
Composition, geometry, and emplacement dynamics of a large volcanic island landslide offshore Martinique: From volcano flank‐collapse to seafloor sediment failure?
Authors: Brunet Morgane , Le Friant Anne , Boudon Georges , Lafuerza Sara , Talling Peter , Hornbach Matthew , Ishizuka Osamu , Lebas Elodie , Guyard Hervé ,   IODP Expedition 340 Science Party
Published: November 2015

AbstractLandslides are common features in the vicinity of volcanic islands. In this contribution, we investigate landslides emplacement and dynamics around the volcanic island of Martinique based on the first scientific drilling of such deposits. The evolution of the active Montagne Pelée volcano on this island has been marked by three major flank‐collapses that removed much of the western flank of the volcano. Subaerial collapse volumes vary from 2 to 25 km3 and debris avalanches flowed into the Grenada Basin. High‐resolution seismic data (AGUADOMAR‐1999, CARAVAL‐2002, and GWADASEIS‐2009) is combined with new drill cores that penetrate up to 430 m through the three submarine landslide deposits previously associated to the aerial flank‐collapses (Site U1399, Site U1400, Site U1401, IODP Expedition 340, Joides Resolution, March–April 2012). This combined geophysical and core data provide an improved understanding of landslide processes offshore a volcanic island. The integrated analysis shows a large submarine landslide deposit, without debris avalanche deposits coming from the volcano, comprising up to 300 km3 of remobilized seafloor sediment that extends for 70 km away from the coast and covers an area of 2100 km2. Our new data suggest that the aerial debris avalanche deposit enter the sea but stop at the base of submarine flank. We propose a new model dealing with seafloor sediment failures and landslide propagation mechanisms, triggered by volcanic flank‐collapse events affecting Montagne Pelée volcano. Newly recognized landslide deposits occur deeper in the stratigraphy, suggesting the recurrence of large‐scale mass‐wasting processes offshore the island and thus, the necessity to better assess the associated tsunami hazards in the region.
Evolution of the plasma environment of comet 67P from spacecraft potential measurements by the Rosetta Langmuir probe instrument
Authors: Odelstad E. , Eriksson A. I. , Edberg N. J. T. , Johansson F. , Vigren E. , André M. , Tzou C.‐Y. , Carr C. , Cupido E. 
Published: November 2015

AbstractWe study the evolution of the plasma environment of comet 67P using measurements of the spacecraft potential from early September 2014 (heliocentric distance 3.5 AU) to late March 2015 (2.1 AU) obtained by the Langmuir probe instrument. The low collision rate keeps the electron temperature high (∼5 eV), resulting in a negative spacecraft potential whose magnitude depends on the electron density. This potential is more negative in the northern (summer) hemisphere, particularly over sunlit parts of the neck region on the nucleus, consistent with neutral gas measurements by the Cometary Pressure Sensor of the Rosetta Orbiter Spectrometer for Ion and Neutral Analysis. Assuming constant electron temperature, the spacecraft potential traces the electron density. This increases as the comet approaches the Sun, most clearly in the southern hemisphere by a factor possibly as high as 20–44 between September 2014 and January 2015. The northern hemisphere plasma density increase stays around or below a factor of 8–12, consistent with seasonal insolation change.
Frequency variability of standing Alfvén waves excited by fast mode resonances in the outer magnetosphere
Authors: Archer M. O. , Hartinger M. D. , Walsh B. M. , Plaschke F. , Angelopoulos V. 
Published: November 2015

AbstractCoupled fast mode resonances (cFMRs) in the outer magnetosphere, between the magnetopause and a turning point, are often invoked to explain observed discrete frequency field line resonances. We quantify their frequency variability, applying cFMR theory to a realistic magnetic field model and magnetospheric density profiles observed over almost half a solar cycle. Our calculations show that cFMRs are most likely around dawn, since the plasmaspheric plumes and extended plasmaspheres often found at noon and dusk can preclude their occurrence. The relative spread (median absolute deviation divided by the median) in eigenfrequencies is estimated to be 28%, 72%, and 55% at dawn, noon, and dusk, respectively, with the latter two chiefly due to density. Finally, at dawn we show that the observed bimodal density distribution results in bimodal cFMR frequencies, whereby the secondary peaks are consistent with the so‐called “CMS” frequencies that have previously been attributed to cFMRs.
How increasing CO2 leads to an increased negative greenhouse effect in Antarctica
Authors: Schmithüsen Holger , Notholt Justus , König‐Langlo Gert , Lemke Peter , Jung Thomas 
Published: November 2015

AbstractCO2 is the strongest anthropogenic forcing agent for climate change since preindustrial times. Like other greenhouse gases, CO2 absorbs terrestrial surface radiation and causes emission from the atmosphere to space. As the surface is generally warmer than the atmosphere, the total long‐wave emission to space is commonly less than the surface emission. However, this does not hold true for the high elevated areas of central Antarctica. For this region, the emission to space is higher than the surface emission; and the greenhouse effect of CO2 is around zero or even negative, which has not been discussed so far. We investigated this in detail and show that for central Antarctica an increase in CO2 concentration leads to an increased long‐wave energy loss to space, which cools the Earth‐atmosphere system. These findings for central Antarctica are in contrast to the general warming effect of increasing CO2.
Development of bifurcated current sheets in solar wind reconnection exhausts
Authors: Mistry R. , Eastwood J. P. , Phan T. D. , Hietala H. 
Published: November 2015

AbstractPetschek‐type reconnection is expected to result in bifurcations of reconnection current sheets. In contrast, Hall reconnection simulations show smooth changes in the reconnecting magnetic field. Here we study three solar wind reconnection events where different spacecraft sample oppositely directed reconnection exhausts from a common reconnection site. The spacecraft's relative separations and measurements of the exhaust width are used to geometrically calculate each spacecraft's distance from the X line. We find that in all cases spacecraft farthest from the X line observe clearly bifurcated reconnection current sheets, while spacecraft nearer to the X line do not. These observations suggest that clear bifurcations of reconnection current sheets occur at large distances from the X line (~1000 ion skin depths) and that Petschek‐type signatures are less developed close to the reconnection site. This may imply that fully developed bifurcations of reconnection current sheets are unlikely to be observed in the near‐Earth magnetotail.
Global maps of ground magnetometer data
Authors: Waters C. L. , Gjerloev J. W. , Dupont M. , Barnes R. J. 
Published: November 2015

AbstractA statistical‐based method combined with basis function expansion techniques is described in order to provide extensive maps of the ground level perturbation magnetic field from 40∘ magnetic latitude to the north magnetic pole for all longitudes. The method combines historical data from the SuperMAG data base, Principal Component Analysis, and a spherical cap harmonic basis function expansion in order to fill in magnetic perturbation data where there are no magnetometers and produce the poloidal current potential. The maps have a regular grid with a 2∘ latitude and 1 h longitude spacing. The statistical process uses SuperMAG data derived magnetic indices plus the solar zenith angle which orders the resulting spatial maps by geomagnetic activity indicators to enhance model agreement with the data. For quiet through to moderate magnetic activity intervals, the root‐mean‐square error between the input and the fitted data are 18 nT and 10 nT for the north‐south and east‐west components, respectively, which are of similar magnitude to the statistical uncertainty in the SuperMAG data set.
Further Simplification of the Simple Erosion Narrowing Score With Item Response Theory Methodology
Authors: Oude Voshaar Martijn A. H. , Schenk Olga , ten Klooster Peter M. , Vonkeman Harald E. , Bernelot Moens Hein J. , Boers Maarten , van de Laar Mart A. F. J. 
Published: November 2015

ObjectiveTo further simplify the simple erosion narrowing score (SENS) by removing scored areas that contribute the least to its measurement precision according to analysis based on item response theory (IRT) and to compare the measurement performance of the simplified version to the original.MethodsBaseline and 18‐month data of the Combinatietherapie Bij Reumatoide Artritis (COBRA) trial were modeled using longitudinal IRT methodology. Measurement precision was evaluated across different levels of structural damage. SENS was further simplified by omitting the least reliably scored areas. Discriminant validity of SENS and its simplification were studied by comparing their ability to differentiate between the COBRA and sulfasalazine arms. Responsiveness was studied by comparing standardized change scores between versions.ResultsSENS data showed good fit to the IRT model. Carpal and feet joints contributed the least statistical information to both erosion and joint space narrowing scores. Omitting the joints of the foot reduced measurement precision for the erosion score in cases with below‐average levels of structural damage (relative efficiency compared with the original version ranged 35–59%). Omitting the carpal joints had minimal effect on precision (relative efficiency range 77–88%). Responsiveness of a simplified SENS without carpal joints closely approximated the original version (i.e., all Δ standardized change scores were ≤0.06). Discriminant validity was also similar between versions for both the erosion score (relative efficiency = 97%) and the SENS total score (relative efficiency = 84%).ConclusionOur results show that the carpal joints may be omitted from the SENS without notable repercussion for its measurement performance.
A Hedonic Valuation of Health and Nonhealth Attributes in the U.S. Yogurt Market
Authors: Bonanno Alessandro 
Published: November 2015

ABSTRACTThe U.S. yogurt category encompasses a multitude of subcategories including products carrying health‐related attributes, some products targeting specific segments of the population (i.e., yogurt for kids), and others of recent introduction (e.g., Greek‐style yogurts). Given the numerous attributes that can be present in a product, characterizing those leading to a higher premium can help manufacturers to engage in profitable product formulation. This paper investigates the role played by health and nonhealth‐related attributes on yogurt prices in the United States, both at the national level and in different geographic markets, by means of a large scanner database of yogurt sales and a hedonic price model. The findings indicate that health‐related attributes more commonly associated with yogurts such as the presence of probiotics, specific health claims, and other credence attributes (i.e., organic and “natural”) are valued positively while others, which may lead to lower product acceptance (e.g., fibers, Omega‐3) are not. Nonhealth‐related features, such as “for kids” and Greek‐style, show a positive market value, thus helping in product differentiation. The magnitude of the implicit price of most product attributes is found to vary across markets, hinting that food manufacturers should consider market‐specific product formulation strategies to achieve product differentiation more effectively.
Skin nerve misfolded α‐synuclein in pure autonomic failure and Parkinson disease
Authors: Donadio Vincenzo , Incensi Alex , Piccinini Cristina , Cortelli Pietro , Giannoccaro Maria Pia , Baruzzi Agostino , Liguori Rocco 
Published: November 2015

ObjectiveTo characterize the expression in skin nerves of native (n‐syn) and misfolded phosphorylated (p‐syn) α‐synucleins in pure autonomic failure (PAF) and idiopathic Parkinson disease (IPD). The specific aims were to (1) define the importance of n‐syn and p‐syn as disease biomarkers and (2) ascertain differences in abnormal synuclein skin nerve deposits.MethodsWe studied 30 patients, including 16 well‐characterized IPD patients and 14 patients fulfilling PAF diagnostic criteria, and 15 age‐matched controls. Subjects underwent skin biopsy from proximal (ie, cervical) and distal (ie, thigh and leg) sites to study small nerve fiber and intraneural n‐syn and p‐syn.ResultsPAF and IPD showed length‐dependent somatic and autonomic small fiber loss, more severely expressed in patients with higher p‐syn load. n‐syn was similarly expressed in both groups of patients and controls. By contrast, p‐syn was not evident in any skin sample of controls but was found in all PAF and IPD patients, although with different skin innervation. In addition, abnormal α‐synuclein deposits were found in all analyzed skin samples in PAF but in only 49% of samples with a higher positivity rate at the proximal site in IPD.Interpretation(1) Intraneural p‐syn was a reliable in vivo marker of PAF and IPD; (2) neuritic p‐syn inclusions differed in PAF and IPD, suggesting a different underlying pathogenesis; (3) when searching for abnormal p‐syn deposits in skin nerves, the site of analysis is irrelevant in PAF but it is critical in IPD. Ann Neurol 2015 Ann Neurol 2016;79:306–316
Synthesis and characterizations of hydrophobically associating water‐soluble polymer with nonionic surfmer
Authors: Ye Zhongbin , Jiang Jinfang , Zhang Xuan , Chen Hong , Han Lijuan , Song Jiarong , Xian Ji , Chen Wei 
Published: November 2015

ABSTRACTIn this article, a hydrophobically associating copolymer (2‐acrylamido)‐2‐methylpropanesulfonic acid (AMPS)/AA‐EO25C12 was synthesized by AMPS and nonionic surfmer AA‐EO25C12 through free radical copolymerization. The structure of copolymer was characterized by FT‐IR and 1H‐NMR. The properties of copolymer were studied and the results indicated that the copolymer exhibits good thickening ability due to intermolecular hydrophobic associations as the apparent viscosity of the copolymer solution increases sharply with increasing polymer concentration. Compared with homopolymer PAMPS, the rheological test indicates that the copolymer solution shows shear thickening behavior at low shear rate region. Besides, the copolymer exhibits interfacial activity as it can reduce the interfacial tension to 10° level, and ability to form emulsion with good stability, which is due to successfully introducing the structure of nonionic surfmer AA‐EO25C12 to the polymer chain. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43195.