bluuebunny/crossref_metadata_2025_split huggingface dataset:
Two-fluid Numerical Simulations of Solar Spicules
Authors: Kuźma Błażej , Murawski Kris , Kayshap Pradeep , Wójcik Darek , Srivastava Abhishek Kumar , Dwivedi Bhola N. 
Published: November 2017

Abstract
We aim to study the formation and evolution of solar spicules by means of numerical simulations of the solar atmosphere. With the use of newly developed JOANNA code, we numerically solve two-fluid (for ions + electrons and neutrals) equations in 2D Cartesian geometry. We follow the evolution of a spicule triggered by the time-dependent signal in ion and neutral components of gas pressure launched in the upper chromosphere. We use the potential magnetic field, which evolves self-consistently, but mainly plays a passive role in the dynamics. Our numerical results reveal that the signal is steepened into a shock that propagates upward into the corona. The chromospheric cold and dense plasma lags behind this shock and rises into the corona with a mean speed of 20–25 km s−1. The formed spicule exhibits the upflow/downfall of plasma during its total lifetime of around 3–4 minutes, and it follows the typical characteristics of a classical spicule, which is modeled by magnetohydrodynamics. The simulated spicule consists of a dense and cold core that is dominated by neutrals. The general dynamics of ion and neutral spicules are very similar to each other. Minor differences in those dynamics result in different widths of both spicules with increasing rarefaction of the ion spicule in time.
The Emergence of the Infrared Transient VVV-WIT-06*
Authors: Minniti D. , Saito R. K. , Forster F. , Pignata G. , Ivanov V. D. , Lucas P. W. , Beamin J. C. , Borissova J. , Catelan M. , Gonzalez O. A. , Hempel M. , Hsiao E. , Kurtev R. , Majaess D. , Masetti N. , Morrell N. I. , Phillips M. M. , Pullen J. B. , Rejkuba M. , Smith L. , Surot F. , Valenti E. , Zoccali M. 
Published: November 2017

Abstract
We report the discovery of an enigmatic large-amplitude (

mag) transient event in near-IR data obtained by the VISTA Variables in the Via Lactea (VVV) ESO Public Survey. The object (designated VVV-WIT-06) is located at R.A. = 17:07:18.917, decl. = −39:06:26.45 (J2000), corresponding to Galactic coordinates l = 347.14539, b = 0.88522. It exhibits a clear eruption, peaking at Ks = 9 mag during 2013 July and fading to

in 2017. Our late near-IR spectra show post-outburst emission lines, including some broad emission lines (upward of

km s−1). We estimate a total extinction of

mag in the surrounding field, and no progenitor was observed in ZYJHKs images obtained during 2010–2012 (down to

mag). Subsequent deep near-IR imaging and spectroscopy, in concert with the available multiband photometry, indicate that VVV-WIT-06 may be either: (i) the closest Type I SN observed in about 400 years, (ii) an exotic high-amplitude nova that would extend the known realm of such objects, or (iii) a stellar merger. In all of these cases, VVV-WIT-06 is a fascinating and curious astrophysical target under any of the scenarios considered.
New VVV Survey Globular Cluster Candidates in the Milky Way Bulge*
Authors: Minniti Dante , Geisler Douglas , Alonso-García Javier , Palma Tali , Beamín Juan Carlos , Borissova Jura , Catelan Marcio , Clariá Juan J. , Cohen Roger E. , Ramos Rodrigo Contreras , Dias Bruno , Fernández-Trincado Jose G. , Gómez Matías , Hempel Maren , Ivanov Valentin D. , Kurtev Radostin , Lucas Phillip W. , Moni-Bidin Christian , Pullen Joyce , Alegría Sebastian Ramírez , Saito Roberto K. , Valenti Elena 
Published: November 2017

Abstract
It is likely that a number of Galactic globular clusters remain to be discovered, especially toward the Galactic bulge. High stellar density combined with high and differential interstellar reddening are the two major problems for finding globular clusters located toward the bulge. We use the deep near-IR photometry of the VISTA Variables in the Vía Láctea (VVV) Survey to search for globular clusters projected toward the Galactic bulge, and hereby report the discovery of 22 new candidate globular clusters. These objects, detected as high density regions in our maps of bulge red giants, are confirmed as globular cluster candidates by their color–magnitude diagrams. We provide their coordinates as well as their near-IR color–magnitude diagrams, from which some basic parameters are derived, such as reddenings and heliocentric distances. The color–magnitude diagrams reveal well defined red giant branches in all cases, often including a prominent red clump. The new globular cluster candidates exhibit a variety of extinctions (0.06 < A
Ks < 2.77) and distances (5.3 < D < 9.5 kpc). We also classify the globular cluster candidates into 10 metal-poor and 12 metal-rich clusters, based on the comparison of their color–magnitude diagrams with those of known globular clusters also observed by the VVV Survey. Finally, we argue that the census for Galactic globular clusters still remains incomplete, and that many more candidate globular clusters (particularly the low luminosity ones) await to be found and studied in detail in the central regions of the Milky Way.
Association of vitamin D binding protein polymorphisms with response to therapy in Egyptian chronic hepatitis C patients
Authors: Kamel Ahmed Mohamed , Farid Samar Farghali , Attia Ahmed Sherif , El. Raziky Maissa 
Published: November 2017

Introduction: Vitamin D binding protein (VDBP) is a potential modulator of immune response and is associated with clinical progression of many diseases. Our aim was to assess influence of baseline 25-hydroxyvitamin D levels and VDBP single nucleotide polymorphisms (SNPs), rs4588 (C > A) and rs7041 (G > T), on baseline clinical parameters and response to interferon based therapy in chronic hepatitis C patients in Egypt.
Methodology: Genotyping was performed by RFLP (Restriction Fragment Length Polymorphism) in 112 treatment naïve hepatitis C patients and 50 healthy controls. Vitamin D levels were assessed by ELISA. HCV RNA quantification was performed by PCR to assess therapy outcome.
Results: Patients with VDBP WT+ diplotype (3 or 4 VDBP major alleles) had higher viral response rates at weeks 12, 48, and 72 (p = 0.046, 0.034 and 0.029, respectively) and lower base line viral load (p = 0.016). Multivariate logistic regression identified VDBP WT+ diplotype as an independent predictor of sustained viral response (SVR; p = 0.014, RR = 4.716, 95% CI = 1.371 – 16.609). Interestingly, WT- diplotype (less than 3 VDBP major alleles) was associated with significant liver fibrosis (p = 0.045).
Conclusions: VDBP WT+ diplotype is associated with lower baseline viral load and better therapy outcome in HCV treatment naïve patients. The rs4588 genotype is associated with SVR in the Egyptian population.
Human immunodeficiency virus prevalence and risk determinants among people who inject drugs in the Republic of Georgia
Authors: Shengelia Natia , Chikovani Ivdity , Sulaberidze Lela 
Published: November 2017

Introduction: In Georgia as in most Eastern European countries, injecting drug use remains one of the leading transmission modes of HIV infection. This paper aims to identify HIV prevalence and risk determinants among people who inject drugs (PWID).
Methodology: A cross -sectional, anonymous bio-behavioral survey of PWID was conducted in seven cities of Georgia in 2014-2015. Overall 2,022 PWID were investigated. Bivariate and multivariate regression analyses were performed to identify association of HIV positivity with other factors.
Results: HIV prevalence among PWID was (2.2%, 95% CI 1.53-2.99). Significant associations were found between HIV positivity and history of drug injection (OR 1.03, p < 0.05), older age at first drug injection (OR 3.94, p < 0.01), safe sex behavior last year (OR 5.32, p < 0.01) and preventive program coverage (OR 2.0, p < 0.05).
Conclusions: HIV prevalence among PWID is stable and remains at low level. Our study shows that preventive interventions influence the sexual behavior of HIV positive PWID, however, the majority of injecting drug users are still not reached with these interventions. A changing environment may present additional challenges for harm reduction and current safe practices may change unless continuously supported by innovative HIV prevention programming.
Toxin production and drug resistance profiles of pediatric methicillin-resistant Staphylococcus aureus isolates in Tehran
Authors: Esmaeili Benvidi Mozhgan , Houri Hamidreza , Ghalavand Zohreh , Nikmanesh Bahram , Azimi Hadi , Samadi Roghayeh , Nodeh Farahani Narges , Eslami Gita 
Published: November 2017

Introduction: Staphylococcus aureus is known to be a major cause of skin and soft tissue infections, pneumonia and invasive diseases. In this study, attempts were made to examine the prevalence of tsst-1, eta, etb, and luk-PV genes among methicillin-resistant S. aureus (MRSA) isolated from children in Tehran.
Methodology: In the present cross-sectional study, a total of 100 MRSA were isolated from children who were referred to a pediatric hospital during 11-month period of September 2014 to August 2015. Isolates were identified using biochemical tests and then, using PCR, the isolates were tested for the presence of mecA, tsst-1, eta, etb, and luk-PV genes. Susceptibility of isolates to cefoxitin, penicillin, erythromycin, clindamycin, gentamicin, rifampin, minocycline, co-trimoxazole, linezolid, and vancomycin were evaluated using standard methods.
Results: It was found that the MRSA isolates had the greatest resistance to clindamycin (72%) and erythromycin (59%), while the lowest rates of resistance were observed to be related to minocycline (6%) and rifampin (12%). All of isolates were sensitive to vancomycin and linezolid. The mecA gene was detected in all the isolates. Moreover, luk-PV and tsst-1 were detected in 18% and 17% of the isolates, respectively. None of the isolates harbored eta and etb genes.
Conclusions: Our data provide specifications about the toxin production status of S. aureus isolates from pediatric children. The current study showed increased resistance to different antibiotics in S. aureus isolates. Therefore, to prevent multi-resistance to other antibiotic classes, it is essential to withhold prescriptions and stop unessential use of available antibiotics.
Expliquer la rupture du Programme commun de gouvernement en septembre 1977
Authors: Batardy Christophe 
Published: November 2017

Le 12 juillet 1972, le Parti communiste français (PCF), le Parti socialiste (PS) et les radicaux de gauche signent un accord programmatique, le Programme commun de gouvernement, appelé très vite Programme commun. Les discussions sur l’actualisation débutent en mai 1977 pour échouer en septembre 1977. Le Programme n’est dès lors plus partagé et la gauche perd les élections législatives de mars 1978. Une lecture chronologique de la période qui court de mai à septembre 1977 permet de revenir sur les causes de cette rupture, et de réévaluer la responsabilité du Parti communiste et de son secrétaire général Georges Marchais.
Marie Claire , magazine féministe ?
Authors: Pavard Bibia 
Published: November 2017

Existe-t-il un féminisme populaire porté par la presse féminine ? L’étude de cas du cahier « Femmes » de Marie Claire , autoproclamé « journal des féministes » dans le magazine de 1976 à 1990, permet d’analyser finement les mécanismes de diffusion de discours militants dans la culture de masse. L’étude qualitative de la rubrique couplée à des entretiens avec les professionnels qui l’ont animée montrent que cette expérience éditoriale originale est rendue possible par le poids du contexte politique s’articulant avec le contexte organisationnel de l’entreprise et les trajectoires des journalistes. Le magazine propose une rubrique qui suit l’air du temps, permettant à une jeune génération d’entrer dans la rédaction et d’y faire carrière.
A Hard(y) Look at B-1 Cell Development and Function
Authors: Baumgarth Nicole 
Published: November 2017

Abstract
A small population of B cells exists in lymphoid tissues and body cavities of mice that is distinct in development, phenotype, and function from the majority (B-2) B cell population. This population, originally termed “Ly-1” and now “B-1,” has received renewed interest as an innate-like B cell population of fetal-derived hematopoiesis, responsible for natural Ab production and rapid immune responses. Molecular analyses have begun to define fetal and adult hematopoiesis, while cell-fate mapping studies have revealed complex developmental origins of B-1 cells. Together the studies provide a more detailed understanding of B-1 cell regulation and function. This review outlines studies that defined B-1 cells as natural Ab- and cytokine-producing B cells of fetal origin, with a focus on work conducted by R.R. Hardy, an early pioneer and codiscoverer of B-1 cells, whose seminal contributions enhanced our understanding of this enigmatic B cell population.
Fan-Out Wafer-Level Packaging (FOWLP) of Large Chip with Multiple Redistribution-Layers (RDLs)
Authors: Lau John , Li Ming , Fan Nelson , Kuah Eric , Li Zhang , Tan Kim Hwee , Chen Tony , Xu Iris , Li Margie , Cheung Y. M. , Kai Wu , Hao Ji , Beica Rozalia , Taylor Tom , Ko CT , Yang Henry , Chen YH , Lim Sze Pei , Lee NC , Ran Jiang , Wee Koh Sau , Yong Qingxiang , Xi Cao , Tao Mian , Lo Jeffery , Lee Ricky 
Published: November 2017

Abstract
This study is for fan-out wafer-level packaging (FOWLP) with chip-first (die face-up) formation. The chips with Cu contact-pads on the front-side and a die attach film (DAF) on the backside are picked and placed face-up on a temporary glass wafer carrier with a thin layer of light-to-heat conversion (LTHC) material. It is followed by compression molding with epoxy molding compound (EMC) and post mold cure (PMC) on the reconstituted wafer carrier, and then backgrinding the molded EMC to expose the Cu contact-pads of the chips. The next step is to build up the redistribution layers (RDLs) from the Cu contact-pads and then mount the solder balls. Next comes the de-bonding of the carrier with a laser, and then the dicing of the whole reconstituted wafer into individual packages. A 300mm reconstituted wafer with a package/die ratio = 1.8 and a die-top EMC cap = 100μm has also been fabricated (a total of 325 test packages on the reconstituted wafer.) This test package has three RDLs; the line width/spacing of the first RDL is 5μm/5μm, of the second RDL is 10μm/10μm, and of the third RDL is 15μm/15μm. The dielectric layer of the RDLs is fabricated with a photosensitive polyimide (PI) and the conductor layer of the RDLs is fabricated by electrochemical Cu deposition (ECD).
Investigation & Resolution of Current Leakage Failure caused by Carbon Black Aggregation in Mold Compound
Authors: Singh Akhilesh Kumar , Lau Teck Beng , Lakhera Nishant , James Hoffmann , Low Boon Yew 
Published: November 2017

Abstract
Encapsulation materials (e.g. mold compounds) are inherently designed to have very high resistivity (volume resistivity of &gt; 1013 Ohm.cm) to avoid any current leakage or shorting of pins. However, multiple ingredients in mold compound, if processed inappropriately, have enough conductivity to cause significant leakage resulting poor yield and/or inferior quality of products. For a Molded Array Process Ball Grid Array (MAPBGA) package, high current leakage (&gt; 1 μA) failure was observed. For standard electronic packages, the allowable leakage is in the range of two to three order of magnitude lower than the leakage observed. Significant current leakage was observed at a specific pin using a standard organic substrate. The problem persisted across multiple substrate suppliers. Electrical and failure analysis did not suggest interlayer dielectric cracking or wire bond related anomalies. Secondary factors such as mold flow direction, mold cap thickness and substrate design aggravated the current leakage issue. Curve trace was able to isolate the problem away from die, and toward package assembly. Further, strategically designed experiments successfully led to the root cause. Current leakage was caused by formation of conductive path between two pins due agglomeration of carbon black in mold compound. Thermogravimetric analysis (TGA) technique was used to characterize the moisture uptake of carbon black and to differentiate between agglomerated and finely disperse carbon black. With the material improvement (change in the carbon black pH to avoid agglomeration), the leakage mechanism was fully understood and the problem was resolved. Surface of carbon black particle was modified by further oxidation process resulting in lower pH, finely dispersed carbon black.
Prototyping and Production of High-temperature Power Electronic Substrates through Additive Manufacturing Processes
Authors: Stoll Thomas , Syed-Khaja Aarief , Franke Joerg 
Published: November 2017

Abstract
This paper reveals a study on Selective Laser Melting (SLM) as an alternative technology for producing power electronic substrates, and shows the possibility of producing a stable interface between alumina and copper through SLM technique. Additive Manufacturing (AM) has not yet been established in the manufacturing of electronic devices. The prevalent benefits of the generative manufacturing sector such as material efficiency, product customization/–flexibility, elimination of the usage of tools, constructional freedom and less process steps in contrast to the conventional fabrication methods of ceramic substrates for power electronic applications like DBC or AMB, are pointed out. Moreover, AM reduces energy costs due to the elimination of the necessary firing, etching and washing processes. The realized study focuses on the examination of adhesion strengths of copper structures, melted on different Al2O3 ceramics with and without pre-copper and -glass paste coating. The melting process was categorized for different laser parameters (1–3) based on the same energy input. Maximum shear values of the substrate probes reached were at about 30 N/mm2 for copper coated ceramic, and at 20 N/mm2 for conventional and glass paste coated substrates. All results were determined in a full factorial design of experiment (DoE) with 54 combinations and a sample size of six samples per parameter combination. Furthermore, several cross sections of the probes produced were illustrated to better understand the melting and joining behavior of the copper powder applied on the ceramic substrates. For improved mechanical adhesion, the ceramic substrates were roughened by laser radiation, with roughness values measured, and the cracking behavior of the exposed ceramics explained.
A Generic Strategy to Assess and Mitigate Chip Package Interaction Risk Factors for Semiconductor Devices with Ultra-low k Dielectric Materials in Back End of Line
Authors: Kuechenmeister Frank , Breuer Dirk , Geisler Holm , Klewer Christian , Boehme Bjoern , Machani Kashi Vishwanath , Hecker Michael , Goetze Christian , Cho Jae Kyu , Kamineni Himani , Paul Jens , Thiele Michael 
Published: November 2017

Abstract
This paper describes a systematic approach to the identification of primary contributing factors to the Chip Package Interaction (CPI) risk and reveals the mitigation strategy successfully applied by GLOBALFOUNDRIES. The strategy includes modeling at bump and package level, gathering experimental data on blanket dielectric back end of line (BEoL) films, collecting data on wafer material with a complete BEoL stack, and finally using readouts on the package level.
Advanced measurement methods generate data on the wafer level to achieve fast turn-around times. These methods include: (i) Dual-Cantilever Beam (DCB) test, (ii) Modified Edge Lift-off Test (MELT), (iii) Single Pillar Shear Test (SPST) and (iv) Bump Assisted BEoL Stability Indentation (BABSI) tests. The paper describes the methodology to gather data on the wafer level with a complete BEoL metallization stack that assesses the BEoL integrity.
Furthermore, the package level thermomechanical modeling approach is discussed. The model has been used to determine the critical factors on BEoL stress/strain during the flip-chip assembly reflow processes.
Silicon design-related factors in the BEoL that contribute to the risk for CPI related failures were investigated and options to reduce the CPI risk are discussed. Finally the paper reveals package level qualification data flip-chip CSP and wafer level packaging Fan-In for advanced technology nodes.
Investigation of Wafer Level Packaging schemes for 3D RF interposer multi-chip module
Authors: Vereecke Bart , Soussan Philippe , Zhu Jian 
Published: November 2017

AbstractVery small RF modules can be realized through heterogenous integration of GaAs MMIC (monolithic microwave integrated circuit) onto a low loss Si sub-mount, with high density routing lines realized by advanced patterning. In this paper we investigate how to integrate MMIC active devices on GaAs with the RF passives produced on an interposer, using Si wafer process technology. High resistive Silicon substrates are required to minimize RF losses. The interposer is thinned below 100 μm to reveal Cu TSVs from the back of the interposer, while the front side is covered entirely with a silicon capping wafer for shielding the device. We compare different wafer level packaging approaches for producing the low RF-loss interposers, and populating them using die-to-die (D2D) or die-to-wafer (D2W) bonding of the MMIC components, followed by wafer level encapsulation. Two D2W approaches are compared, in the first approach the D2W mounting and the encapsulation happens before the Si interposer is thinned for TSV reveal. To avoid damage during thinning of the wafer, thicker substrates with deeper TSV of 150 μm or more are required. In a second approach, the thinning of the interposer is done prior to the mounting. Initial electrical data showed that the approach yielded proper RF performance, but further yield optimization is required.