bluuebunny/crossref_metadata_2025 huggingface dataset:
Pigmentosins from Gibellula sp. as antibiofilm agents and a new glycosylated asperfuran from Cordyceps javanica
Authors: Helaly Soleiman E , Kuephadungphan Wilawan , Phainuphong Patima , Ibrahim Mahmoud A A , Tasanathai Kanoksri , Mongkolsamrit Suchada , Luangsa-ard Janet Jennifer , Phongpaichit Souwalak , Rukachaisirikul Vatcharin , Stadler Marc
Published: December 2019

In the course of our exploration of the Thai invertebrate-pathogenic fungi for biologically active metabolites, pigmentosin A (1) and a new bis(naphtho-α-pyrone) derivative, pigmentosin B (2), were isolated from the spider-associated fungus Gibellula sp. Furthermore, a new glycosylated asperfuran 3, together with one new (6) and two known (4 and 5) cyclodepsipeptides, was isolated from Cordyceps javanica. The pigmentosins 1 and 2 showed to be active against biofilm formation of Staphylococcus aureus DSM1104. The lack of toxicity toward the studied microorganism and cell lines of pigmentosin B (2), as well as the antimicrobial effect of pigmentosin A (1), made them good candidates for further development for use in combination therapy of infections involving biofilm-forming S. aureus. The structure elucidation and determination of the absolute configuration were accomplished using a combination of spectroscopy, including 1D and 2D NMR, HRMS, Mosher ester analysis, and comparison of calculated/experimental ECD spectra. A chemotaxonomic investigation of the secondary metabolite profiles using analytical HPLC coupled with diode array detection and mass spectrometry (HPLC–DAD–MS) revealed that the production of pigmentosin B (2) was apparently specific for Gibellula sp., while the glycoasperfuran 3 was specific for C. javanica.
EOQ FOR PERISHABLE GOODS: MODIFICATION OF WILSON’S MODEL FOR FOOD RETAILERS
Authors: Zeng Shouzhen , Nestorenko Oleksandr , Nestorenko Tetyana , Morkūnas Mangirdas , Volkov Artiom , Baležentis Tomas , Zhang Chonghui
Published: December 2019

A timely response to a fluctuating and ever-changing consumer demand is an important decision for a company, as it may impact its position in the market. Thus, proper inventory management becomes a focal point in retail business process management and can provide a substantial competitive advantage. In this paper, we introduce a modified version of Wilson’s model, which takes into account trends in consumer demand and offer flexibility in reordering time. The illustration of the proposed model is presented, showing the significant economic benefit under particular conditions.
Ensemble Average of Three-dimensional Minkowski Tensors of a Gaussian Random Field in Redshift Space
Authors: Appleby Stephen , Kochappan Joby P. , Chingangbam Pravabati , Park Changbom
Published: December 2019

We present the ensemble expectation values for the translation-invariant, rank-2 Minkowski tensors in three dimensions, for a linearly redshift-space-distorted Gaussian random field. The Minkowski tensors

,

are sensitive to global anisotropic signals present within a field, and by extracting these statistics from the low-redshift matter density one can place constraints on the redshift-space distortion parameter β = f/b. We begin by reviewing the calculation of the ensemble expectation values

,

for isotropic, Gaussian random fields, then consider how these results are modified by the presence of a linearly anisotropic signal. Under the assumption that all fields remain Gaussian, we calculate the anisotropic correction due to redshift-space distortion in a coordinate system aligned with the line of sight, finding inequality between the diagonal elements of

,

. The ratio of diagonal elements of these matrices provides a set of statistics that are sensitive only to the redshift-space distortion parameter β. We estimate the Fisher information that can be extracted from the Minkowski tensors, and find

is more sensitive to β than

, and a measurement of

accurate to ∼1% can yield a

constraint on β. Finally, we discuss the difference between using the matrix elements of the Minkowski tensors directly against measuring the eigenvalues. For the purposes of cosmological parameter estimation we advocate the use of the matrix elements, to avoid spurious anisotropic signals that can be generated by the eigenvalue decomposition.
Nonthermal Motions in a Polar Coronal Hole Measured with Hinode/EIS during an on-Orbit Partial Solar Eclipse on 2017 August 21
Authors: Hara Hirohisa
Published: December 2019

We have performed a spectroscopic observation over the south polar coronal hole (PCH) with the Hinode Extreme-ultraviolet (EUV) Imaging Spectrometer (EIS) during an on-orbit partial solar eclipse. In this partial eclipse, the Moon passed through the EIS observing area that was set in the south PCH at the height of 0.9–1.4 solar radii. Using the lunar occultation, we have corrected for the scattered light contamination from bright regions of the Sun that is present in the dark PCH emission line profiles. The nonthermal width of the corrected emission line profile in the PCH increases from the limb toward the high-altitude corona. It has also been confirmed that the nonthermal width tends to decrease beyond ∼1.2 solar radii. These results are consistent with the model in which outward-propagating Alfvén waves start being dissipated at ∼1.2 solar radii, as previously reported. The reduced energy within ∼1.4 solar radii contributes to atmospheric heating and the initial acceleration for the solar wind in the low corona. The remaining energy flux at 1.4 solar radii may be dissipated in the distant corona and is sufficient to provide the additional acceleration required to drive the fast solar wind.
High-redshift Galaxy Formation with Self-consistently Modeled Stars and Massive Black Holes: Stellar Feedback and Quasar Growth
Authors: Kim Ji-hoon , Wise John H. , Abel Tom , Jo Yongseok , Primack Joel R. , Hopkins Philip F.
Published: December 2019

As computational resolution of modern cosmological simulations come closer to resolving individual star-forming clumps in a galaxy, the need for “resolution-appropriate” physics for a galaxy-scale simulation has never been greater. To this end, we introduce a self-consistent numerical framework that includes explicit treatments of feedback from star-forming molecular clouds (SFMCs) and massive black holes (MBHs). In addition to the thermal supernovae feedback from SFMC particles, photoionizing radiation from both SFMCs and MBHs is tracked through full three-dimensional ray tracing. A mechanical feedback channel from MBHs is also considered. Using our framework, we perform a state-of-the-art cosmological simulation of a quasar-host galaxy at z ∼ 7.5 for ∼25 Myr with all relevant galactic components, such as dark matter, gas, SFMCs, and an embedded MBH seed of ≳106
M
⊙. We find that feedback from SFMCs and an accreting MBH suppresses runaway star formation locally in the galactic core region. Newly included radiation feedback from SFMCs, combined with feedback from the MBH, helps the MBH grow faster by retaining gas that eventually accretes on to the MBH. Our experiment demonstrates that previously undiscussed types of interplay between gas, SFMCs, and a MBH may hold important clues about the growth and feedback of quasars and their host galaxies in the high-redshift universe.
Turbulent Heating in Solar Wind Thermodynamics
Authors: Livadiotis G.
Published: December 2019

This paper considers the concept of wave-particle thermodynamic equilibrium in order to improve our understanding of the role of turbulent heating in the solar wind proton plasma. The thermodynamic equilibrium in plasmas requires the energy of a plasmon—the quantum of plasma fundamental oscillation—to be balanced by the proton-magnetized plasma energy, that is, the magnetic field and proton kinetic/thermal energy. This equilibrium has already been confirmed in several prior analyses, but also in this paper, by analyzing (i) multi-spacecraft data sets along the radial profile of the inner heliosphere, and (ii) representative data sets of a variety of 27 different space and astrophysical plasmas. Recently, it was shown that the slow mode of the near-Earth solar wind plasma is characterized by a missing energy source that is necessary for keeping the energy balance in the plasmon–proton-magnetized plasma. Here we show strong evidence that this missing energy is the turbulent energy heating the solar wind. In particular, we derive and compare the radial and velocity profiles of this missing energy and the turbulent energy in the inner heliosphere, also considering other minor contributions, such as the temperature of pickup protons. The connection of the missing plasmon–proton energy with the turbulent energy provides a new method for estimating and cross-examining the turbulent energy in space and astrophysical plasmas, while it confirms the universality of the involved new Planck-type constant that implies a large-scale quantization.
Mapping Spatial Variations of H i Turbulent Properties in the Small and Large Magellanic Cloud
Authors: Szotkowski Samuel , Yoder Delano , Stanimirović Snežana , Babler Brian , McClure-Griffiths N. M. , Dénes Helga , Bolatto Alberto , Jameson Katherine , Staveley-Smith Lister
Published: December 2019

We developed methods for mapping spatial variations of the spatial power spectrum (SPS) and structure function slopes, with the goal of connecting the statistical properties of neutral hydrogen (H i) with the turbulent drivers. The new methods were applied to the H i observations of the Small and Large Magellanic Clouds (SMC and LMC). In the case of the SMC, we find highly uniform turbulent properties of H i, with no evidence for local enhancements of turbulence due to stellar feedback. These properties could be caused by a significant turbulent driving on large scales. Alternatively, the significant line-of-sight depth of the SMC could be masking out localized regions with a steeper SPS slope caused by stellar feedback. In contrast to the SMC, the LMC H i shows a large diversity in terms of its turbulent properties. Across most of the LMC, the small-scale SPS slope is steeper than the large-scale slope due to the presence of the H i disk. On small spatial scales, we find several areas of localized steepening of the SPS slope around major H ii regions, with the 30 Doradus region being the most prominent. This is in agreement with predictions from numerical simulations, which suggest a steepening of the SPS slope due to stellar feedback that erodes and destroys interstellar clouds. We also find a localized steepening of the large-scale SPS slope in the outskirts of the LMC. This is likely caused by the flaring of the H i disk, or alternatively, by ram-pressure stripping of the LMC disk due to the interactions with the surrounding halo gas.
Selank and semax as potential hepatoprotectors in medical treatment of tuberculosis
Authors: Petrovsky Alexey K. , Smirnov Nikolay A. , Vdovichenko Vladimir P. , Fedorova Tatiana B. , Kerbenev Edgar E. , Fedorov Vladimir N.
Published: December 2019

Introduction: Drug-induced hepatitis is common in clinical practice. This problem is particularly relevant in the treatment of tuberculous infection, because for this purpose, up to 5–6 hepatotoxic drugs are used simultaneously for a long time, which often (in 15–20% of cases) leads to medical liver lesion. To protect the liver, Semax and Selank are offered – drugs of regulatory peptides group.

Materials and Methods: The research was conducted on 96 outbred white male rats weighing 180–220 g. The experimental group included about 10 animals. Drug-induced hepatitis was simulated through the combined 21-day administration of isoniazid, rifampicin and ethanol. Semax and Selank, as well as Essentiale N and Mexidol (comparison drugs) were administered once a day during the experiment. Healthy control animals with experimental hepatitis were used for comparison. Subsequently, the obtained biochemical and histomorphological parameters were evaluated.

Results and Discussion: In the experiment, Semax and Selank showed a greater therapeutic activity than the recognized hepatoprotectors – Essentiale and Mexidol. Only in the case of administering Selank and Semax, there was parallelism between the restoration of biochemical parameters of blood and histomorphological parameters of the liver. Selank was also characterized by an increased activity of regenerative processes.

Conclusion: Administering Selank and Semax to patients with tuberculosis would significantly reduce the number and severity of hepatotoxic reactions.
The Reliability of Kager's Triangle in Detecting Acute Achilles Tendon Ruptures
Authors: Belyea Christopher M. , Krul Kevin P. , Lause Gregory , Magee Anthony , Anderson Claude D. , Ryan Paul M.
Published: December 2019

The Achilles tendon is a common site of anatomical injury among athletes and those participating in recreational sporting activities. Acute Achilles tendon ruptures are often misdiagnosed as a sprained ankle and are more common in the male population. Mechanism of injury is often a noncontact injury, resulting from sudden forced plantar flexion or violent dorsiflexion in a plantar flexed foot. Delays in diagnosis and treatment may complicate the clinical outcome. Because findings may be subtle on history and physical examination, the use of readily available adjunctive studies is important for practitioners. One method is the analysis of Kager's triangle on lateral ankle radiographs. Obscuration of Kager's triangle has been described as a radiographic indicator of Achilles tendon rupture, but the sensitivity and specificity of this finding have been poorly reported. [
Orthopedics
. 2020; 43(2): e91–e94.]
O ensino de desenho: um olhar sobre os cursos do departamento de artes da Universidade Federal do Paraná (1981-1987)
Authors: Silva Rossano , Vaz Adriana
Published: December 2019

O presente artigo se propõe a investigar o ensino de desenho nos cursos oferecidos pelo Departamento de Artes (DEARTES) da Universidade Federal do Paraná (UFPR), a saber os cursos de desenho industrial e as licenciaturas em educação artística, habilitação artes plásticas e desenho. O recorte da pesquisa investiga os currículos vigentes entre os anos de 1981 a 1987, nos quais as disciplinas de desenho eram ministradas tanto pelo DEARTES como pelo Departamento de Desenho (DDES), que mantinham configurações diferentes sobre a concepção de desenho. A organização do trabalho está dividida em três partes: 1) Interlocuções entre os Departamentos de Artes e Desenho; 2) Currículo de Desenho Industrial, ComunicaçãoVisual e das habilitações de Desenho e Artes Plásticas; 3) Prescrições do ensino de desenho e plástica. Para realizar a análise proposta, o referencial teórico utilizado se vale do conceito de figuração de Elias, campo de Bourdieu e as contribuições sobre a história das disciplinas de Chervel e Goodson. As fontes utilizadas são documentos oficiais, programas de disciplinas e atas. O que permitiu analisar as prescrições sobre o desenho que compunham o currículo dos cursos citados.
Stability of chewing louse (Phthiraptera: Amblycera and Ischnocera) populations infesting great horned owls (Aves: Strigidae)
Authors: Lamb Robert J. , Galloway Terry D.
Published: December 2019

The annual abundance of chewing lice (Phthiraptera) was recorded on great horned owls (Bubo virginianus(Gmelin), Aves: Strigidae) from 1994 to 2015 in Manitoba, Canada.Kurodaia magnaEmerson (Amblycera: Menoponidae) had a mean annual abundance about half that forStrigiphilus oculatus(Rudow) (Ischnocera: Philopteridae). Mean intensity, rather than prevalence, explained the variation in annual abundance. Temporal variation (measured as population variability) in abundance and mean intensity were high and similar (0.62–0.67), but lower for nymph to female ratio (0.36–0.38). Temporal variation of prevalence and sex ratio were higher forK. magna(0.34–0.35) than forS. oculatus(0.21–0.22), and typical for other louse species. The high temporal variability for abundance and mean intensity suggest lower year-to-year stability than exhibited by other chewing lice, but over 80% of this variability was due to sampling error resulting from small sample sizes in some years and extreme intensities in the aggregated distributions of intensity. The remaining variation, < 20%, revealed no significant differences in annual abundance or mean intensity among years, and therefore stable populations over 22 years. Populations of 12 species of chewing lice show lower temporal variability and therefore greater stability than three other insect taxa.
Low Loss Photodielectric Materials for 5G HS/HF Applications
Authors: Hayes Colin O. , Wang Kevin , Bell Rosemary , Calabrese Colin , Kong Jeff , Paik Jennie , Wei Lingyun , Thompson Kirk , Gallagher Michael , Barr Robert K.
Published: December 2019

Fifth generation network technology, often referred to as 5G, holds great potential for higher communication speeds, higher data transmission rates and improved connectivity, however, current dielectric materials lack sufficiently low dielectric loss (Df) at desired form factors for next-generation devices. While photoimageable dielectrics will certainly play a role in 5G manufacturing, many of the chemistries that have evolved and are suitable for photodielectrics (aqueous developed and polar solvent developed materials) have a Df that is too high for a 5G devices. Arylalkyl thermoset polymers (ATPs) have long been known for its low dielectric properties and found use in many high frequency applications, especially GaAs devices. An existing ATP photodielectric, CYCLOTENE™ 4000 Series Dielectric is characterized and compared to a newly designed experimental platform herein called 5G-XP-1. The platform developed utilizes new monomer and polymer chemistry to deliver a system capable of low temperature cure within 1 hour between 170–200°C, self-priming adhesion on silicon, copper, silicon nitride and polyimide and low Df at high frequency in a full formulation (<0.005 20–40GHz). 5G-XP-1 is deposited as a spin on photodielectric material but is still capable of achieving a variety of final film thicknesses from 15–25 μm. More importantly the formulation can achieve high aspect ratio imaging with 1:1 AR vias using an i-Line Karl Süss Mask Aligner. Moreover, this photodielectric material can be developed using environmentally-friendly solvents, such as esters like propylene glycol monomethyl ether acetate (PGMEA). The new experimental material 5G-XP-1 spin on photodielectric material demonstrates considerable promise for next-generation 5G devices, with future improvements on mechanical properties already in progress.
How Relevant is Packaging for 5G?
Authors: Ndip Ivan , Töpper Michael , Lang Klaus-Dieter
Published: December 2019

In this contribution, the role of packaging in the development of 5G mmWave antennas and passive components, as well as in the system-integration of these components together with active components for the development of 5G mmWave systems is discussed.
A Novel Fabrication Process for High Density Silicon Capacitors by using Metal-Assisted Chemical Etching
Authors: Obata Susumu , Sano Mitsuo , Shimokawa Kazuo , Higuchi Kazuhito
Published: December 2019

In silicon capacitors, it is most important to increase the surface area of the surface forming the capacitor. In conventional silicon capacitors, trenches are generally formed in silicon wafer using reactive ion etching (RIE) method to expand their surface area. However, with this method, the depth of trenches that can be formed was limited. Furthermore, since RIE method processes silicon wafer only one by one, productivity is low. In this paper, Metal-assisted Chemical Etching (MacEtch) is proposed as a novel method of fabricating high-density silicon capacitors to solve the problems. We used gold formed by electroless plating as a catalyst and controlled them by forming conditions. As a result, vertical trenches greater than 100 μm depth and less than 1 μm width could be formed on a silicon wafer. The silicon wafer on which these trenches are formed has a surface area 100 times or more as compared with the case where there is no trench. We formed a dielectric film and electrodes on these trench surfaces. Consequently, we have realized a silicon capacitors with a capacitance density as high as 200 nF / mm2 or more.
Failure Analysis of Interconnection Fault in a PoP Module Applied for Mobile Phone
Authors: Xiao Hui , Li Wei , Shi Gaoming
Published: December 2019

A typical early fault case of some mobile phones was studied in this paper. The failure phenomenon was manifested as that the mobile phones could not be powered on after one year in their service, with the malfunction rate having reached about 2% of the whole yield in the same manufacturing lot as the fault machines returned from client side continuously. The results of fault location showed that there was interconnection failure in the main chip module, which used package on package (PoP) packaging. A series of experimental technique was used for the failure analysis, such as 3D X-ray inspection, shadow moiré test, microsectioning, scanning electron microscope (SEM), electron backscattered diffraction (EBSD) analysis, etc. The results showed that some solder joints' through cracking in the PoP module was the immediate cause of the mobile phones' malfunction, and the main reason for the cracking was thermal-mechanical fatigue with recrystallization microstructure degradation. It is important to further study on the technological method for controlling grain orientations in electronic interconnections.
Advanced Package Design: Inter-Domain Design Methodologies
Authors: Acito Bill ,   IC Packaging Product Engineer
Published: December 2019

Just as we transitioned from simplistic lead frames to large ball grid arrays decades ago, we find ourselves again at another inflection point in design. Originally a derivative of PCB design, IC package design finds itself straddling both PCB-style design and traditional IC design. Dimensions have shrunk to place IC package design squarely in the same design dimensions as integrated circuits. Likewise, with Moore's law rapidly losing steam to support SoC's as a system integration vehicle, advanced package technologies have been asked to fill the system enablement gap. We now see advanced packaging technologies with silicon content as the system enabler in 2.5D, 3D and fanout wafer-level packaging. Because of the silicon and small geometries, IC design flows and signoff mechanisms are being used to design the next-generation of packaged systems.

Package design now finds itself in the forefront of system-level design enablement. Where once system aggregation was done in a SoC at the silicon level, packaging is being used to build a system from technology-optimized die from each functional area (memory, processing, and interfaces). Silicon is no longer just a substrate material for IC manufacturing but a “package” substrate and functional integration vehicle. As such, package design teams find themselves adding IC-based design flows and methodologies. Package designers must look to the IC tools for routing, DRC, and signoff capabilities.

Designers are looking for next-generation EDA tools to support these new integration and design challenges, including LVS-like validation checks and IC-based design rules. Rather than transitioning the design team from traditional packaging tools to IC tools entirely, we propose that users can leverage complete design flows that merge the best-in-class capabilities from each of their respective design domains. Is this regard, the best-in-class capabilities can remain in their respective domains, and a design flow can be created that relies on tight integration between both domains. These flows can also leverage a single point of entry for design capture and system level management. Flows based on the system management tool and the appropriate features in each of the domains can be created that enable and optimize complex designs that meet physical, signal integrity, cost and performance requirements. We will describe how capabilities can be leveraged from both domains in a tightly coupled flow, overseen by a design system-management tool, to address the challenges of advanced-technology and silicon-based system.
Early detection and instantaneous cause analysis of defects in interconnects by machine learning (ranking-CNN) of scattering parameter patterns
Authors: Kang Tae Yeob , Seo Donghwan , Park Yongchan , Min Joonki , Kim Taek-Soo
Published: December 2019

This paper presents a novel method not only to detect defects in interconnects early but also to determine the root causes instantaneously by using machine learning of scattering parameter(s-parameter) patterns. it is found out that defective interconnects have certain and unique s-parameter patterns. We modified the facial age estimating algorithm (ranking-CNN) to learn the s-parameter patterns according to the cause and severity of defects in interconnects. Utilizing the training datasets obtained from pristine, cracked and photodegraded ITO specimens, our algorithm returns information on the cause of the interconnect defect and the severity level with accuracies of 95.56% and 91.11% respectively.
Thermal Modeling and Experimental Analysis of High Power LED using POL-kw Packaging Technology
Authors: Kapusta Christopher , Yin Liang , Nagarkar Kaustubh , Walwaikar Anisha , Srihari Krishnaswami
Published: December 2019

In this paper, an “embedded chip” packaging platform using POL-kW packaging for use with High Power LED devices is presented. Prototype samples have been fabricated and tested. The authors will describe thermal modeling analysis as well as experimental results from the prototype samples. A thermal simulation model has been developed to look at the thermal properties and attributes of the POL-kW LED structure and will be compared to conventional AlN and IMS based LED packages. The process flow and fabrication details of a POL-kW LED package will be summarized to provide a better understanding of the technical and performance advantages. Initial results have shown that the presence of POL vias directly connected to the LED chip reduce the thermal path and, thereby, the thermal resistance of the package. Furthermore, the POL-kw LED package offers a thinner profile and smaller form factors which allows higher integration density.
A multi-pronged approach to low-pressure Cu sintering using surface-modified particles, substrate and chip metallization
Authors: Bhogaraju Sri Krishna , Mokhtari Omid , Pascucci Jacopo , Conti Fosca , Kotadia Hiren R , Elger Gordon
Published: December 2019

High temperature power electronics based on wide-bandgap semiconductors have prominent applications, such as automotive, aircrafts, space exploration, oil/gas extraction, electricity distribution. Die-attach bonding process is an essential process in the realization of high temperature power devices. Here Cu offers to be a promising alternative to Ag, especially because of thermal and mechanical properties on par with Ag and a cost advantage by being a factor 100 cheaper than Ag. With the aim to achieve a low-pressure Cu sintering process, a low cost wet chemical etching process is developed to selectively etch Zn from brass to create nano-porous surface modifications to enhance sinterability, enabling sintering with low bonding pressure of 1MPa and at temperatures below 300°C. However, high tendency of Cu to oxidize poses a major challenge in realizing stable interconnects. For this purpose, in this contribution, we present the use of polyethylene-glycol 600 as reducing binder in the formulation of the Cu sintering paste. Finally, we propose a multi-pronged approach based on three crucial factors: surface-modified substrates, nanostructured surface modifications on micro-scale Cu-alloy particles and use of a reducing binder in the Cu particle paste.
Characterization and Electrical Performance of Glass Diplexer Modules
Authors: Woychik Charles , Lauffer John , Pollard Scott , Parmar Raj , Gaige Michael , Wilson William , Carey James , Neely Matthew , Ling Feng , Chen Lijun
Published: December 2019

A process has been developed to manufacture a glass diplexer module using conventional laminate circuit board processes that have been adapted to handle glass substrates. Over the past few years we have evaluated both Cu plating and electrically conductive adhesives (ECAs) to produce a through glass via (TGV). From this work, it has been determined that Cu plating is a preferred process to form a robust TGV in a manufacturing environment. A Cu plated TGV nicely compliments our semi-additive plating (SAP) processes to produce fine line Cu circuitry on both sides of a glass substrate. In addition, we have successfully laminated an Ajinomoto Buildup Film (ABF) to both sides of a glass substrate having TGVs. The ABF completely filled the vias and also maintained uniform flatness on both sides. The resulting interposer was very flat and suitable for the next level of Cu plating using SAP. The ABF material was able to form high quality blind vias using laser drilling. A more comprehensive characterization of the glass diplexer modules will be presented, which will include X-sections of a double-sided Cu circuitry and Cu MIM (metal-insulator-metal) capacitors and inductors. In addition, the first set of electrical test data will be presented and compared with the modeling work done to date.
THERMAL VALIDATIONS OF ADDITIVE MANUFACTURED NON-METALLIC HEAT SPREADING DEVICE FOR HOT SPOT MITIGATION IN POWER MODULES
Authors: Whitt Reece , Huitink David
Published: December 2019

As energy demands and power electronics density scale concurrently, reliability of such devices is being challenged. Inadequate thermal management can cause system-wide failures due to thermal run-away, thermal expansion induced stresses, interconnect fractures and many more. Conventional techniques used to cool devices consist of heavy, metallic systems such as cold plates and large heat sinks, which can significantly reduce the overall system power density. Moreover, the manufacturing of such components is expensive and often requires custom-made cold plates for improved integration with the electronic system. Although used as a standard practice, these metallic thermal management systems have the potential to intensify electro-magnetic interference (EMI) when coupling with high frequency switching power electronics, and the material density increases the weight of the system, which is detrimental in mobile applications. Lastly, cold plates and heat sinks can create non-uniform cooling profiles in the electronics due to the insufficient management of hot-spots. To combat these drawbacks, a new heat spreader design has been proposed which reduces weight and EMI effects while eliminating hot-spots through localized fluid impingement. This current study describes the methodology and construction of the experimental test setup to characterize the performance of the heat spreading device compared to an off-the-shelf cold plate. Through infrared imagining, the viability of two heated test sections are evaluated in their ability to replicate power module temperature profiles during operation.
Semi-additive Process Based Cu Wirings with Ultra Smooth Electroless Cu Seed Layer and Important Factor for High Frequency Transmission Property
Authors: Toba Masaya , Nomoto Shuji , Komuro Nobuhito , Mitsukura Kazuyuki , Abe Shinichiro , Masuko Takashi , Kurafuchi Kazuhiko
Published: December 2019

Semiconductor packages for high performance devices with printed circuit boards having multi wiring layers such as FC-BGA have been attracting the attention in order to realize ultra-reliable and low latency communications in 5G networking. Cu wirings for the package are usually fabricated by via formation by laser for dielectric, desmear, electroless Cu seed formation, photoresist patterning, electrolytic Cu plating, resist stripping and seed layer etching. Though a desmear process can obtain enough adhesion between dielectric and Cu seed layer by anchoring effect to secure reliabilities, the interface between dielectric and Cu seed layer should be smooth to achieve low attenuation of electric signals at high frequencies. Here, instead of a desmear process, we applied an UV modification for the surface of dielectric in order to realize a smooth and high adhesive seed layer against dielectric. We obtained 0.8 kN/m of peel strength between dielectric and Cu seed layer in spite of surface roughness (Ra) of dielectric was 45 nm by nano-level anchoring effect at UV modified layer. Due to the smooth interface by UV modification, S21 value of microstrip line was 26 % improved compared to that assembled through desmear process at 60 GHz.
Understanding the Effects of Process Parameters to Compensate for Substrate Warpage in Chip on Flex (CoF) Assembly Using Conventional Reflow
Authors: Soman Varun , Venkatadri Vikram , Poliks Mark D.
Published: December 2019

Mounting rigid silicon (Si) die on a flex substrate presents a unique set of challenges. Substrate surface flatness and warpage of the flex substrate before and during thermal processing being two of the biggest issues. Various processes such as thermocompression bonding using anisotropic conductive films and thermosonic bonding using non-conductive adhesives have been shown to be effective for chip on flex (CoF) applications. However, these processes sacrifice process throughput and are less cost effective. Hence these methods may not be suitable for high volume manufacturing (HVM). For this reason, a process that is suitable for HVM and uses standard reflow processes and equipment is highly desirable. This works presents preliminary results for such a CoF process that uses a simple fixture and standard processes, materials and equipment. CoF process for Si die using two types of interconnects, solder balls or Cu pillars, was developed. Solder paste was stencil printed before pick and place of the Si die to offset the lack of flex substrate flatness and substrate warpage. The effect of stencil aperture diameter and placement force on process yield and stand-off height was studied. It was demonstrated that high yield can be obtained with a process that uses wider stencil aperture opening for both type of interconnects investigated. It was also observed that the placement force did not have any effect on process yield or stand-off height. The process can also be easily scaled up for HVM.
Reconfigurable mm Wave Flexible Packages with Ultra-thin Fan-Out Embedded Tunable Ceramic IPDs
Authors: Bhardwaj Shubhendu , Sayeed S K Yeahia Been , Camara Jose Solis , Vital Dieff , Raj P. M.
Published: December 2019

In this work, we show the use of tunable ceramic type integrated passive devices for mm-wave antenna applications. The specific illustrations are made using BST (barium strontium titanate) based capacitator, whose capacitances can be changed by electronically controlled permittivity of the BST material. BST capacitors with capacitance variation from 0.5 pF to 1 pF are designed (requiring a control voltage between 0 to 5 V) and using these capacitors, RF-components are designed. Specifically, we show a design of reconfigurable band-pass filter in 28 GHz band and reconfigurable phase-shifters in 28 GHz and 38 GHz mm Wave bands. We show that the electronic control provides enough phase-shift variation for ±90° beam-steering antennas covering the entire broadside scanning range in 28 GHz and 38 GHz bands. Furthermore, bandpass filter that is reconfigurable around 28 GHz band is designed to demonstrate full band reconfigurability to block undesired signals that enter the receiver chains for jamming applications.
Recent Advances in X-ray for Semicon Applications
Authors: Bryant Keith , Vaga Ragnar
Published: December 2019

Taking x-ray images goes back over 100 years. Since then, there have been numerous advances in x-ray technology and these have been increasingly applied in helping the manufacturing of electronic components and assemblies, as well as in their failure analysis.

Most recently, this has been rapidly driven by the reduction in device and feature size and the movement to using newer, lower density materials within the structures, such as copper wire replacing gold wire as the interconnection material of choice within components. Another driver for developments is the engineering of single 3D packages with multiple chips stacked vertically one on top of the other, which results in smaller and more efficient packaging of devices.

In order to meet these challenges and those in the future, there have been a number of recent key improvements to the vital components within x-ray systems.

The choice of available technologies, however, means selecting the tube/detector combination, which is optimum for a particular electronics inspection application, is no longer so clear-cut. For example, one configuration may provide certain benefits that are applicable for one area of electronics inspection, whilst being less valid for others. This paper will review the various x-ray tube and detector types that are available and explain the implications of these choices for electronics inspection in terms of what they provide for inspection regarding image resolution, magnification, tube power, detector pixel size and the effects of detector radiation damage, amongst others.

This paper will also look in detail at the capabilities of high end CT systems to inspect wafer bumps, copper pillars and TSV's, new designs are reducing key dimensions of all of these interconnections challenging x-ray systems to produce clear images.
Reliability of printed wire bonds
Authors: Marsan-Loyer C. , Sansregret C.
Published: December 2019

Additive manufacturing is an emerging domain with numerous potential applications. The concept of those new processes offers many advantages such as design flexibility, truly 3D packages and low cost for customization. The aerosol jet printing could enable wire bonding-like techniques that are unachievable with round wires today, combined with serious advantages for high frequency applications. However, this new field is starting off with many challenges to address, with the reliability as a focal point. The focus of this study is the reliability of printed wire bonds. Polyimide and silver inks were printed using an aerosol jet system (OPTOMEC Aerosol Jet ® HD Decathlon™). The results are focusing on the reliability of the adhesion of polyimide ink (UTD-PI-AJ) in an ethanol-based diluent and a silver ink, the HPS-108AE1 from Novacentrix, on different surface types: silicon oxide, pure aluminum and gold (ENIG). The adhesion is first addressed by a qualitative tape test at room temperature. The test samples are then put into an environmental chamber for a Deep Thermal Cycling (DTC) stress. The samples cycled 1000 times between −20°C and 85°C. They were inspected for physical defects at 250, 500 and 750 cycles. The visual inspection for defects focuses on cracks and delamination. The printed wire bonds were simulated by printing polyimide ink into a gold plated flat ceramic substrate (28 LCC from Kyocera) and then printing conductive silver ink from opposite pin leads. A layer of polyimide ink was then added on top of the printed lines. Crossover lines were finally printed on top of the last polyimide layer, again from opposite pin leads, creating an array of superimposed printed wire bonds. The reliability of printed wire bonds is tested through a Highly Accelerated Stress Test (HAST, 110°C, 85%RH, 264h) under bias. The samples were inspected at 66h, 132h and 198h for visual defects such as cracks, delamination and silver electro-migration. Cross-sections were performed on samples before and after HAST. All defects were characterized regarding of their time and condition or appearance and of their dimensions.
Testate amoebae (Amoebozoa: Arcellinidae) as indicators of dissolved oxygen concentration and water depth in lakes of the Lacandón Forest, southern Mexico
Authors: Charqueño Celis Norma Fernanda , Garibay Martin , Sigala Itzel , Brenner Mark , Echeverria-Galindo Paula , Lozano Socorro , Massaferro Julieta , Pérez Liseth
Published: December 2019

The ecology of aquatic protists such as testate amoebae is poorly known worldwide, but is almost completely unknown in lakes of the northern Neotropics. To address this knowledge gap, we analyzed testate amoebae (Amoebozoa: Arcellinidae) in lakes of the Lacandón Forest, one of the most biodiverse parts of southern México. We set out to evaluate the diversity of testate amoebae communities and assess whether testate amoebae taxa are reliable indicators of environmental variables dissolved oxygen and water depth. We collected 17 surface sediment samples from a range of water depths in six lakes across the Naha-Metzabok Biosphere Reserve, northeastern Chiapas state. We identified 15 testate amoebae taxa distributed across seven genera. Eleven were identified to species level and four to strain (infra-subspecific level), and taxa were distributed unevenly among samples. Distribution of taxa in samples was related to dissolved oxygen (DO) concentration in the water measured near the sediment surface. Arcella discoides and Centropyxis aculeata strain “aculeata” were the most tolerant of low oxygen concentrations, whereas the other taxa require higher DO levels. The influence of oxygen was also seen at the assemblage level. Sites with low DO concentrations had Shannon Diversity Index (SDI) values <1.5, an indication of stressful ambient conditions. We identified two species assemblage types, which are distinguished by their oxygen concentration requirements. Assemblage 1 was more diverse and possessed species that are intolerant of low oxygen concentrations, whereas Assemblage 2 possessed fewer, rarer, opportunistic species that tolerate stressful conditions. Low oxygen concentrations are related to water depth and the combination of these two variables is important in determining the composition of testate amoebae assemblages in Lacandón Forest lakes. Quantitative relationships between testate amoebae assemblages and water depth will enable use of sedimented amoebae remains for paleolimnological inference of past water level changes in lakes of the Lacandón Forest.
Existence and Uniqueness of Solutions to Singular p-Laplace Equations of Kirchhoff Type
Authors: Li Qingwei
Published: December 2019

In this paper, we study both the existence and uniqueness of nonnegative solutions for the nonlocal $p$-Laplace equation with singular term $$\begin{eqnarray}\left\{\begin{array}{@{}ll@{}}-B\Bigl(\frac{1}{p}\int _{\unicode[STIX]{x1D6FA}}|\unicode[STIX]{x1D6FB}u|^{p}\text{d}x\Bigr)\unicode[STIX]{x1D6E5}_{p}u=\frac{h(x)}{u^{\unicode[STIX]{x1D6FE}}}+k(x)u^{q},\quad & x\in \unicode[STIX]{x1D6FA},\\ u>0,\quad & x\in \unicode[STIX]{x1D6FA},\\ u=0,\quad & x\in \unicode[STIX]{x2202}\unicode[STIX]{x1D6FA},\end{array}\right.\end{eqnarray}$$ where $\unicode[STIX]{x1D6FA}\subset \mathbb{R}^{N}(N\geqslant 1)$ is a bounded domain with smooth boundary $\unicode[STIX]{x2202}\unicode[STIX]{x1D6FA}$, $h\in L^{1}(\unicode[STIX]{x1D6FA})$, $h>0$ almost everywhere in $\unicode[STIX]{x1D6FA}$, $k\in L^{\infty }(\unicode[STIX]{x1D6FA})$ is a non-negative function, $B:[0,+\infty )\rightarrow [m,+\infty )$ is continuous for some positive constant $m$, $p>1$, $0\leqslant q\leqslant p-1$, and $\unicode[STIX]{x1D6FE}>1$. A “compatibility condition” on the couple $(h(x),\unicode[STIX]{x1D6FE})$ will be given for the problem to admit at least one solution. To be a little more precise, it is shown that the problem admits at least one solution if and only if there exists a $u_{0}\in W_{0}^{1,p}(\unicode[STIX]{x1D6FA})$ such that $\int _{\unicode[STIX]{x1D6FA}}h(x)u_{0}^{1-\unicode[STIX]{x1D6FE}}\text{d}x<\infty$. When $k(x)\equiv 0$, the weak solution is unique.
Concordance, Crossing Changes, and Knots in Homology Spheres
Authors: Davis Christopher W.
Published: December 2019

Any knot in $S^{3}$ can be reduced to a slice knot by crossing changes. Indeed, this slice knot can be taken to be the unknot. In this paper we study the question of when the same holds for knots in homology spheres. We show that a knot in a homology sphere is nullhomotopic in a smooth homology ball if and only if that knot is smoothly concordant to a knot that is homotopic to a smoothly slice knot. As a consequence, we prove that the equivalence relation on knots in homology spheres given by cobounding immersed annuli in a homology cobordism is generated by concordance in homology cobordisms together with homotopy in a homology sphere.
Don’t Stress about Ulcer Prophylaxis
Authors: MacLaren Robert
Published: December 2019

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Prévention des ulcères : pas de stress!
Authors: MacLaren Robert
Published: December 2019

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For Patients Needing Oral Anticoagulation for Atrial Fibrillation and Dual Antiplatelet Therapy after Percutaneous Coronary Intervention, Is Double Therapy Preferred over Triple Therapy?
Authors: Dryden Lindsay , Kertland(Pro) Heather , Chua(Con) Doson
Published: December 2019

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Conservation and maintenance of the rammed earth of the Historic City Wall of Pingyao，China
Authors: Shibing Dai , Hongsong Li
Published: December 2019

Una de las características más destacadas de la antigua muralla de la ciudad de Pingyao, declarada Patrimonio Mundial en 1997, es la estructura de tapia tras la fábrica de ladrillo que recubre el perímetro externo. A pesar de las muchas intervenciones de consolidación y restauración llevadas a cabo durante las pasadas décadas, aún existen tramos de la muralla que corren el riesgo de derrumbarse. Se han realizado ensayos de laboratorio que muestran que el material de construcción principal de las murallas de Pingyao, es pobre en arcillas, y por lo tanto, no es resistente al agua sin un tratamiento previo. A partir de 2011 y tras un examen cualitativo, se ha restaurado la tapia dañada usando exclusivamente la técnica tradicional de la tapia. Sin embargo, la inspección llevada a cabo en septiembre de 2018, ha permitido determinar que el uso de morteros mixtos de cal y arena como capa de mortero de sacricio puede ser una solución técnica y económicamente más sostenible.
Ao modo de Saccheri
Authors: Sautter Frank Thomas
Published: December 2019

I will apply a technique employed by Giovanni Girolamo Saccheri in Logica demonstrative  (1701) to concisely prove the invalidity of moods of the First Figure of the Theory of the Assertoric Syllogism without appealing to facts outside logic.
Competição intrapartidária nas eleições para deputado federal: um estudo exploratório sobre São Paulo em 2014
Authors: Souza Cíntia Pinheiro Ribeiro de , Graça Luís Felipe Guedes da
Published: December 2019

Esse artigo aborda o tema da competição intrapartidária nas eleições proporcionais de lista aberta. Embora a literatura espere que as regras eleitorais brasileiras incentivem a concorrência direta por votos entre correligionários, poucos são os esforços para mensurar os níveis dessa competição. A partir de correlações de votos, por zonas eleitorais, discutimos os graus de sobreposição espacial das candidaturas dentro de quatro partidos na disputa pelo cargo de deputado federal no estado de São Paulo em 2014. Encontramos variações nos níveis de competição intrapartidária que indicam diferentes estratégias de coordenação na seleção de candidatos. Essa variedade mostra que, além dos incentivos das regras eleitorais, as respostas estratégicas dos agentes a essas regras não devem ser negligenciadas ao tratar desse tema.