bluuebunny/crossref_metadata_2025 huggingface dataset:
Lead-free Solder Joint Reliability – State of the Art and Perspectives
Authors: Pan Jianbiao , Wang Jyhwen , Shaddock David M.
Published: October 2015

There is an increasing demand for replacing tin-lead (Sn/Pb) solders with lead-free solders in the electronics industry due to health and environmental concerns. The European Union recently passed a law to ban the use of lead in electronic products. The ban will go into effect in July of 2006. The Japanese electronics industry has worked to eliminate lead from consumer electronic products for several years. Although currently there are no specific regulations banning lead in electronics devices in the United States, many companies and consortiums are working on lead-free solder initiatives including Intel, Motorola, Agilent Technologies, General Electric, Boeing, NEMI and many others to avoid a commercial disadvantage. The solder joints reliability not only depends on the solder joint alloys, but also on the component and PCB metallizations. Reflow profile also has significant impact on lead-free solder joint performance because it influences wetting and microstructure of the solder joint. A majority of researchers use temperature cycling for accelerated reliability testing since the solder joint failure mainly comes from thermal stress due to CTE mismatch. A solder joint failure could be caused by crack initiation and growth or by macroscopic solder facture. There are conflicting views of the reliability comparison between lead-free solders and tin-lead solders. This paper first reviews lead-free solder alloys, lead-free component lead finishes, and lead-free PCB surface finishes. The issue of tin whiskers is also discussed. Next, lead-free solder joint testing methods are presented; finite element modeling of lead-free solder joint reliability is reviewed; and experimental data comparing lead-free and tin-lead solder joint reliability are summarized. Finally the paper gives perspectives of transitions to totally lead-free manufacturing.
Properties and Stability of Thick-Film Resistors with Low Processing Temperatures - Effect of Composition and Processing Parameters
Authors: Menot-Vionnet Sonia , Maeder Thomas , Grimaldi Claudio , Jacq Caroline , Ryser Peter
Published: October 2015

In this work, the properties (sheet-resistance, temperature coefficient and piezoresistance / gauge factor) and stability of thick-film resistors with low firing temperatures (525…650°C) are studied. To this end, two low-melting lead borosilicate glass compositions have been chosen, together with RuO2 as conductive filler. The effect on the properties and stability of composition and firing temperature is studied. The stability of the materials is quantified during high-temperature storage (annealing) at 250°C. These results show that reasonable resistive and piezoresistive properties, as well as stability, can be obtained even using lower processing temperatures compatible with deposition onto steel, titanium, aluminum and glass substrates.
Investigation of the Lead-free Solder Joint Shear Performance
Authors: Webster James , Pan Jianbiao , Toleno Brian J.
Published: October 2015

Reflow profile has significant impact on solder joint performance because it influences wetting and microstructure of the solder joint. The purpose of this study is to investigate the effects of reflow profile and thermal shock on the shear performance of eutectic SnPb (SnPb) and Sn3.0Ag0.5Cu (SAC305) solder joints. Test boards were assembled with four different sized surface mount chip resistors (1206, 0805, 0603 and 0402). Nine reflow profiles for SAC 305 and nine reflow profiles for SnPb were developed with three levels of peak temperature (12°C, 22°C, and 32°C above solder liquidus temperature, or 230°C, 240°C, and 250°C for SAC 305; and 195°C, 205°C, and 215°C for SnPb) and three levels of time above solder liquidus temperature (30 sec., 60 sec., and 90 sec.). Half of the test vehicles were then subjected to air-to-air thermal shock conditioning from −40 to 125°C. The shear force data were analyzed using the Analysis of Variance (ANOVA). The fracture surfaces were studied using a Scanning Electron Microscopy (SEM) with Energy Dispersive Spectroscopy (EDS). It was found that thermal shock degraded both SnPb and SnAgCu joints shear strength, and that the effect of thermal shock on solder joint shear strength is much more significant than that of reflow profile. The SnAgCu solder joints have weaker shear strength than the SnPb solders. The SnAgCu solder joint after thermal shock retains more of its shear strength than that of SnPb for small components and vice versa for larger components.
Broadband Dielectric Characterization of Aluminum Oxide (Al2O3)
Authors: Rajab Khalid Z. , Naftaly Mira , Linfield Edmund H. , Nino Juan C. , Arenas Daniel , Tanner David , Mittra Raj , Lanagan Michael
Published: October 2015

Applications for low-temperature cofired ceramics (LTCC) and high-temperature cofired ceramics (HTCC) are advancing to higher frequencies. In order to design ceramic microsystems and electronic packages, the electrical properties of materials must be well characterized over a broad frequency range. In this study, the dielectric properties of commercial aluminum oxide (Al2O3) with different glass loadings are characterized using three different measurement techniques: the split-post cavity, terahertz (THz) time-domain spectroscopy, and Fourier transform IR spectroscopy (FTIR). Specifically, the dielectric properties will be characterized from 10 GHz to IR frequencies. A split-post cavity was employed for determination of dielectric properties in the 10 GHz range. A broadband THz spectroscopy technique was used to characterize the specimens using measured time-domain transmission data. The dielectric constant and loss were extracted from the sample's frequency-domain transmission characteristics, providing data between 100 GHz and 2 THz. Additionally, FTIR was used to characterize the samples from ~33 to 3300 cm−1 (~1–100 THz). The measurements from the three techniques are compared, and dielectric constant and loss data will be presented for commercial and experimental ceramic systems from 10 GHz to IR frequencies.
Numerical Prediction of Thermal Performance of Water Cooled Multi-Stack Microchannel Heat Sink with Counterflow Arrangement
Authors: Hegde Pradeep , Patil Mukesh , Seetharamu K. N.
Published: October 2015

Thermal performance of a water cooled multistack microchannel heat sink with counterflow arrangement has been analyzed using the finite element method. Performance parameters such as thermal resistance, pressure drop, and pumping power are computed for a typical counterflow heat sink with different number of stacks. The temperature distribution in a typical multistack counterflow microchannel heat sink is obtained for different numbers of stacks and plotted along the channel length. A parametric study involving the effects of number of stacks and channel aspect ratio on thermal resistance and pressure drop of the heat sink is done. The finite element model developed for the analysis is simple and consumes less computational time.
Feasibility Study of a 3D IC Integration System-in-Packaging (SiP) from a 300 mm Multi-Project Wafer (MPW)
Authors: Lau J. H. , Zhan C.-J. , Tzeng P.-J. , Lee C.-K. , Dai M.-J. , Chien H.-C. , Chao Y.-L. , Li W. , Wu S.-T. , Hung J.-F. , Tain R.-M. , Lin C.-H. , Hsin Y.-C. , Chen C.-C. , Chen S.-C. , Wu C.-Y. , Chen J.-C. , Chien C.-H. , Chiang C.-W. , Chang H.-H. , Tsai W.-L. , Cheng R.-S. , Huang S.-Y. , Lin Y.-M. , Chang T.-C. , Ko C.-D. , Chen T.-H. , Sheu S.-S. , Wu S.-H. , Chen Y.-H. , Lo W.-C. , Ku T.-K. , Kao M.-J. , Hu D.-C.
Published: October 2015

The feasibility of a 3D IC integration SiP has been demonstrated in this investigation. The heart of this SiP is a TSV (through-silicon via) interposer with an RDL (redistribution layer) on both sides, IPD (integrated passive devices), and SS (stress sensors). This interposer is used to support (with microbumps) a stack of four memory chips with TSVs, one thermal chip with heater and one mechanical chip with SS, and is then overmolded on its top side for pick and place purposes. The interposer's bottom side is attached to an organic substrate (with ordinary lead-free solder bumps), which is lead-free solder-balled on a PCB (printed circuit board). Key enabling technologies such as TSV etching, chemical mechanical polishing (CMP), thin-wafer handling, thermal management, and microbumping, assembly, and reliability are highlighted.
Oxide Liner, Barrier and Seed Layers, and Cu Plating of Blind Through Silicon Vias (TSVs) on 300 mm Wafers for 3D IC Integration
Authors: Wu Chien-Ying , Chen Shang-Chun , Tzeng Pei-Jer , Lau John H. , Hsu Yi-Feng , Chen Jui-Chin , Hsin Yu-Chen , Chen Chien-Chou , Shen Shang-Hung , Lin Cha-Hsin , Ku Tzu-Kun , Kao Ming-Jer
Published: October 2015

In this study, key enabling technologies such as the oxide liner by the PECVD, the barrier and seed layers by the PVD, and Cu plating of blind TSVs on 300 mm wafers for 3D integration are investigated. Emphasis is placed on the determination and optimization of the important parameters for each of the key enabling technologies. Also, the leakage current of the fabricated Cu-filled TSVs is measured. Furthermore, cross sections and SEM of the fabricated TSVs are examined.
LTCC-3D Coaxial Flow Focusing Microfluidic Reactor for Micro and Nanoparticle Fabrication and Production Scale-Out
Authors: Gongora-Rubio Mario Ricardo , de Novais Schianti Juliana , Gomez Houari Cobas , da Costa Teves Andre
Published: October 2015

Miniaturization of chemical processes is becoming a must for green chemistry and sustainable industry processes, so technological research in this direction is well received. Continuous microreactor systems hold many potential benefits over batch reactors, in that they allow: high surface-to-volume ratio, fine adjustment of chemical reaction residence times, small thermal inertia, and fast changes in temperature. Advantages of multilayer green ceramics for microprocess applications include: that the LTCC substrate is chemically inert to most solvents, that it has a high contact angle, that it presents low thermal coefficient of expansion, and that it can withstand high operational temperatures and high internal pressures. For these reasons, LTCC-based microsystem technologies allow the implementation of different unitary operations for chemical processes, making it an enabling technology for the miniaturization of chemical processes. In fact, recently, LTCC microfluidic reactors have been used to produce microparticles and nanoparticles with excellent control of size distribution and morphology. The present work provides a report on the performance of a 3D LTCC coaxial flow focusing micro-fluidic reactor designed to fabricate microparticles and nano-particles using nanoprecipitation through an antisolvent; with electric potential size tuning. We also implement an approach to particle production scale-out.
The Impact of Hydrogen Gas Evolution on Blister Formation in Electroless Cu Films
Authors: Bernhard Tobias , Brüning Frank , Brüning Ralf , Sharma Tanu , Brown Delilah , Zarwell Sebastian , Bishop Craig
Published: October 2015

Electroless Cu plating is a key process to provide electrically conductive layers on insulating substrates for the subsequent Cu electroplating of printed-circuit boards (PCBs). Recently introduced substrate materials are prone to spontaneous delamination failure (blistering) of the electroless layer during deposition. A higher Ni content in electroless Cu baths prevents delamination failure by increasing the internal tensile stress in the Cu layer. This effect is achieved by suppressing Cu self-diffusion through the incorporation of small amounts of Ni in the grain boundaries and the grain boundary junctions. Whether the hydrogen gas evolved inevitably during electroless Cu deposition and potentially trapped in the deposit may cause blistering is still under debate. Here we test this hypothesis by quantifying the generated hydrogen gas volume during Cu deposition in baths with Ni concentrations between 0 and 1000 ppm, and observing the rate of blister formation in the deposit. We find a constant molar ratio of 0.65 ± 0.05 mol H2/mol Cu independent of the Ni content in the bath, in contrast to a systematic and substantial change of the blister probability. From this lack of a correlation between the blister rate and hydrogen evolution, we rule out hydrogen evolution as a determining factor for blister formation.
Теорема характеризации для обобщенного преобразования Радона, возникающего в одной модели математической экономики
Authors: Agal'tsov Aleksey Dmitrievich
Published: October 2015

В работе получен критерий реализации функции в виде функции прибыли в обобщенной модели чистой отрасли. Функция прибыли, в свою очередь, сводится повторным дифференцированием к обобщенному преобразованию Радона, что позволяет получить теорему характеризации для обобщенного преобразования Радона.
Коммутирующие разностные операторы и комбинаторное преобразование Гэйла
Authors: Krichever Igor Moiseevich
Published: October 2015

Построена спектральная теория $n$-периодических строго треугольных разностных операторов $L=T^{-k-1}+\sum_{j=1}^k a_i^j T^{-j}$ и спектральная теория «суперпериодических» операторов, для которых все решения уравнения $(L+1)\psi=0$ являются (анти)периодическими. Доказано, что для любого суперпериодического оператора $L$ порядка $k+1$ существует единственный суперпериодический оператор $\mathcal{L}$ порядка $n-k-1$, который коммутирует с $L$, и показано, что дуальность $L\leftrightarrow \mathcal{L}$ с точностью до некоторой инволюции совпадает с комбинаторным преобразованием Гэйла, введенным недавно в [S. Morier-Genoud, V. Ovsienko, R. E. Schwartz, S. Tabachnikov, Linear difference equations, frieze patterns and combinatorial Gale transform,
Forum Math. Sigma, 2 (2014), e22].
Универсальные группы промежуточного роста и их инвариантные случайные подгруппы
Authors: Benli Mustafa Gokhan , Grigorchuk Rostislav Ivanovich , Nagnibeda Tat'yana Valer'evna
Published: October 2015

В работе приведены примеры групп промежуточного роста с $2^{\aleph_0}$ эргодическими непрерывными инвариантными случайными подгруппами. Эти примеры - универсальные группы, ассоциированные с некоторым семейством групп промежуточного роста.
О централизаторе бесконечного перемешивающего преобразования ранга один
Authors: Ryzhikov Valerii Valentinovich , Thouvenot J.-P
Published: October 2015

В работе устанавливается свойство минимальных самоприсоединений (minimal self-joinings) для перемешивающих преобразований ранга 1, сохраняющих меру бесконечного пространства Лебега. Основным следствием является результат о тривиальности централизатора таких преобразований.
Представления нильпотентных групп: расширения, нейтральные когомологии, пространства Понтрягина
Authors: Kissin Eduard Viktorovich , Shulman Viktor Semenovich
Published: October 2015

В работе получены спектральные критерии когомологической тривиальности расширений представлений связных нильпотентных групп. Далее эти результаты применяются к изучению симметризованных расширений унитарных представлений с помощью конечномерных и теории $J$-унитарных представлений групп в пространствах Понтрягина.
Графы Хенсона и графы Урысона-Хенсона как графы Кэли
Authors: Cherlin Gregory
Published: October 2015

Мы рассматриваем группы, действующие регулярно на графах Хенсона $\Gamma_n$, отвечая на вопрос Питера Камерона, а также изучаем смежные вопросы.
Sustained Presence of Cutaneous Leishmaniasis in Urban Manaus, the Largest Human Settlement in the Amazon
Authors: Benício Ednelza , Cordeiro Mayara , Monteiro Hannah , Saboia Moura Marco Antônio , Oliveira Cintia , Nunes Gadelha Ellen Pricilla , Chrusciak-Talhari Anette , Talhari Carolina , de Lima Ferreira Luiz Carlos , Mira Marcelo Távora , Lima Machado Paulo Roberto , Talhari Sinésio , Schriefer Albert
Published: October 2015

The Amazon is responsible for approximately 40% of the American tegumentary leishmaniasis (ATL) in Brazil. Herein the sustained presence of ATL in Manaus, the largest settlement in the Amazon, was investigated. Records of notification of historic cases, and data from cases prospectively enrolled in the Tropical Medicine Foundation of the Amazonas State were used. Geographic coordinates of prospective patients' living sites were used to detect inner-city clusters of ATL. Infecting Leishmania species was determined by polymerase chain reaction. Among prospectively enrolled subjects, 94.8% were infected with Leishmania (Viannia) guyanensis, 76.7% were male, 30.2% were 0–20 years old, and 69.8% had an urban residence. Historic cases showed a profile similar to that of prospectively enrolled subjects. Several clusters of ATL, widely distributed within the city of Manaus, could be detected. In conclusion, there was a high frequency of disease in young age groups and cases clustered in urban neighborhoods. It cannot be determined from these data whether transmission of these cases occurred within or outside the city of Manaus.
The fate of 5N-nitrate in mesocosms from five European peatlands differing in long-term nitrogen deposition rate
Authors: Zając K. , Blodau C.
Published: October 2015

Abstract. Elevated nitrogen (N) deposition changes the retention, transformation, and fluxes of N in ombrotrophic peatlands. To evaluate such effects we applied a 15N tracer (NH415NO3) at a rate of 2.3 g N m−2 yr−1 to mesocosms of five European peatlands with differing long-term N deposition rates for a period of 76 days of dry and 90 days of wet conditions. We determined background N content and moss length growth, and recovered the 15N tracer from the mosses, graminoids, shrubs, the peat, and dissolved N. Background N contents in Sphagnum mosses increased from 5.5 (Degerö Stormyr, deposition < 0.2 g N m−2 yr−1) up to 12.2 mg g−1 (Frölichshaier Sattelmoor, 4.7–6.0 g N m−2 yr−1). In peat from Degerö nitrate and ammonium concentrations were below 3 mg L−1, whereas up to 30 mg L−1 (nitrate) and 11 mg L−1 (ammonium) was found in peat from Frölichshaier Sattelmoor. Sphagnum mosses (down to 5 cm below surface) generally intercepted large amounts of 15N (0.2–0.35 mg g−1) and retained the tracer most effectively relative to their biomass. Similar quantities of the 15N were recovered from the peat, followed by shrubs, graminoids and the dissolved pool. At the most polluted sites we recovered more 15N from shrubs (up to 12.4 %) and from nitrate and ammonium (up to 0.7 %). However, no impact of N deposition on 15N retention by Sphagnum could be identified and their length growth was highest under high N background deposition. Our experiment suggests that the decline in N retention at levels above ca. 1.5 g m−2 yr−1, as expressed by elevated near-surface peat N content and increased dissolved N concentrations, is likely more modest than previously thought. This conclusion is related to the finding that Sphagnum species can apparently thrive at elevated long-term N deposition rates in European peatlands.
A simple model of the anthropogenically forced CO2 cycle
Authors: Weber W. , Lüdecke H.-J. , Weiss C. O.
Published: October 2015

Abstract. From basic physical assumptions we derive a simple linear model of the global CO2 cycle without free parameters. It yields excellent agreement with the observations reported by the carbon dioxide information analysis center (CDIAC) as time series of atmospheric CO2 growth, of sinks in the ocean and of absorption by the biosphere. The agreement extends from the year 1850 until present (2013). Based on anthropogenic CO2 emission scenarios until 2150, future atmospheric CO2 concentrations are calculated. As the model shows, and depending on the emission scenario, the airborne fraction of CO2 begins to decrease in the year ~ 2050 and becomes negative at the latest in ~ 2130. At the same time the concentration of the atmospheric CO2 will reach a maximum between ~ 500 and ~ 900 ppm. As a consequence, increasing anthropogenic CO2 emissions will make the ocean and the biosphere the main reservoirs of anthropogenic CO2 in the long run. Latest in about 150 years, anthropogenic CO2 emission will no longer increase the CO2 content of the atmosphere.
ADSORPTION OF WATER-EXTRACTABLE PROTEINS IN NATURAL RUBBER LATEX SERUMS BY POLY(METHYL METHACRYLATE)/POLYETHYLENEIMINE CORE-SHELL NANOPARTICLES
Authors: Jivapongvitoon Aditjaya , Sunintaboon Panya , Loykulnant Surapich , Suchiva Krisda
Published: October 2015

Poly(methyl methacrylate)/polyethyleneimine (PMMA/PEI) core-shell nanoparticles were prepared by emulsifier-free emulsion polymerization. Micrographs from a scanning electron microscope and transmission electron microscope displayed their spherical shape with core-shell morphology in which PMMA was a core and PEI was a shell. The PMMA/PEI nanoparticles' ability to adsorb proteins from the serum of commercial low-ammonia preserved fresh field natural rubber latex was illustrated. The driving force for adsorption was proposed to be mainly via electrostatic interaction between the protonated amino groups of PEI chains on the nanoparticles' surface and phospholipids or protein molecules on NR particles. The reduction percentage was about 50%, depending on the content of PMMA/PEI nanoparticles and mixing time. For comparison, the protein reduction performance by the nanoparticles with two additional extracted serums, high-ammonia preserved concentrated NRL and Thai advanced preservative system NRL, which have different initial protein contents and pH values, was also investigated. The preliminary evaluation of PMMA/PEI nanoparticles' performance in sulfur-prevulcanized high-ammonia preserved concentrated NRL was also studied. Its corresponding sheet had lower extractable proteins by 50% and had tensile strength and elongation at break of 25.5 MPa and 715%, respectively.
Injury-Induced Inflammation and Inadequate HSP Expression in Mesothelial Cells upon Repeat Exposure to Dual-Chamber Bag Peritoneal Dialysis Fluids
Authors: Bender Thorsten O. , Kratochwill Klaus , Herzog Rebecca , Ulbrich Andrea , Böhm Michael , Jörres Achim , Aufricht Christoph
Published: October 2015

Purpose

Peritoneal dialysis fluids (PDFs) may induce inadequate heat-shock protein (HSP) expression and injury-related inflammation in exposed mesothelial cells. The aim of this study was to relate cellular injury to these cellular responses in mesothelial cells following repeated exposure to 3 commercial PDFs with different biocompatibility profiles.

Methods

Primary cultures of human peritoneal mesothelial cells (HPMC) were exposed to a 1:2 mixture of cell culture medium and CAPD2 (single-chamber bag PDF; Fresenius, Bad Homburg, Germany), Physioneal (dual-chamber bag PDF; Baxter, Deerfield, IL, USA) or Balance (dual-chamber bag PDF, Fresenius) for up to 10 days exposure time (4 dwells). Supernatant was analyzed for LDH, IL-6, and IL-8, cells for HSP-72 expression, and protein content.

Results

PDF exposure resulted in a biphasic pattern of cell damage switching from an earlier phase with increased injury by single-chamber PDF to a delayed phase with increased susceptibility to dual-chamber PDF. Sterile inflammation was related to LDH release over time and could be reproduced by exposure to necrotic cellular material. PDF exposure resulted in low HSP-72 expression in all tested PDFs.

Conclusions

Exposure to single-chamber as well as to dual-chamber bag PDFs induce increased vulnerability of mesothelial cells to repeated exposure of the same solution. These effects were delayed with dual-chamber PDFs. Injury-induced inflammation and impaired HSP expression upon PDF exposure might initiate a vicious cycle with progredient mesothelial cell damage upon repeated PDF exposure. Certainly, interventional studies and translation of these results into the in vivo system is needed.
Systemic Approach to Malignant Pleural Mesothelioma: What News of Chemotherapy, Targeted Agents and Immunotherapy?
Authors: Signorelli Diego , Macerelli Marianna , Proto Claudia , Vitali Milena , Cona Maria Silvia , Agustoni Francesco , Zilembo Nicoletta , Platania Marco , Trama Annalisa , Gallucci Rosaria , Ganzinelli Monica , Pelosi Giuseppe , Pastorino Ugo , de Braud Filippo , Garassino Marina Chiara , Lo Russo Giuseppe
Published: October 2015

Malignant pleural mesothelioma is a rare cancer with a cause-effect relationship to asbestos exposure. The prognosis is poor and chemotherapy seems the best treatment option. In the last two decades a deeper understanding of mesothelioma carcinogenesis and invasiveness mechanisms has prompted research efforts to test new agents in patients with malignant pleural mesothelioma, but the results have been modest. Attractive preclinical data disappointed in subsequent experimental phases. Other promising agents failed to improve patient outcomes due to high toxicity. Interesting suggestions have come from preliminary data on immunotherapy. Several trials are ongoing and the results are eagerly awaited. The aim of this review is to discuss the most recent news on systemic therapy for advanced malignant pleural mesothelioma.
Clinical Pitfalls in Diagnosis of Nonmuscle-Invasive Bladder Cancer
Authors: Serretta Vincenzo , Gesolfo Cristina Scalici
Published: October 2015

Current global economic crisis imposes healthcare system to reduce unnecessary investigations and increase early detection of tumors, to decrease the costs of an advanced disease. Several diagnostic pitfalls may occur dealing with bladder cancer (BC), particularly in nonmuscle-invasive (NMIBC) one. Hematuria, the commonest sign in NMIBC, is often underestimated. Urinary cytology is highly specific for high-grade tumors, but has a low sensitivity for low-grade BC, is operator dependent, and not always obtainable in clinical practice. Numerous urinary tests are available to ameliorate the accuracy of cytology, but none of them is routinly used in urological practice. Ultrasound could hardly detect a small bladder tumor, especially if located in the bladder neck or in the anterior wall. Computed tomography (CT) is widely adopted as an alternative to conventional urography, but its usefulness in patients with hematuria is still debated. MRI has a higher accuracy than CT for staging BC and evaluate the bladder-wall invasion. A negative cystoscopy cannot exclude Tis and should be accompanied by urinary cytology in patients with suspected Tis or high-risk NMIBC; however, new techniques such as narrow band imaging (NBI) and photodynamic (PDD) increase the detection rate of BC and flat lesions. Nearly half of all diagnostic resections present omission of muscle in the specimen or its mention in the pathology report, which is associated with an increased mortality. An adequate muscle sampling during endoscopic resection is mandatory, particularly in patients with high-grade disease. Recognition of pitfalls in diagnosis and management of BC represents the first step for a correct approach.
Relief in Small and Simple Matters in Belgium
Authors: Voet Stefaan
Published: October 2015

Relief in Small and Simple Matters in Belgium

This article is based on a national report that was written for the XVth World Congress of the International Association of Procedural Law that was held in Istanbul in May 2015 and that focused on Effective Judicial Relief and Remedies in an Age of Austerity. It first of all sketches the general judicial context in Belgium and some of its relevant features: the judicial organisation, the goals of the civil justice system, the course of an ordinary civil lawsuit, the role of the court, and the litigation costs. Next, a detailed and critical overview of the current and future procedures that offer relief in small and simple matters is given. The current summary order for payment procedure, which was introduced in 1967, did not meet its goals. The article concludes that a new trend is emerging in Belgium, namely keeping small and unchallenged claims outside the judiciary and providing for cheaper and more efficient alternatives.
Tinkering in Game Worlds
Authors: Nitsche Michael
Published: October 2015

This essay discusses machinima as a form of media tinkering that combines modifications of technology with content re-mixing. Drawing on parallels to early radio enthusiasts, this essay argues that machinima makers can be understood as digital crafters who use games as production tools as well as cultural reference. Mike Munson’s machinima piece “The Tyrant” (2006), is examined here as exemplary of such combined forms of media re-crafting. Ultimately, the perspective advocated through this analysis demands the inclusion of production processes in our wider understanding of digital art literacy, of which machinima is one manifestation.
Cyclone Xaver seen by geodetic observations
Authors: Fenoglio‐Marc L. , Scharroo R. , Annunziato A. , Mendoza L. , Becker M. , Lillibridge J.
Published: October 2015

Cyclone Xaver pounded the North Sea on 5–6 December 2013 and reached its maximum in the German Bight the second day. Combined geodetic measurements from the SARAL/AltiKa satellite and from a local geodetic network detect cross‐shelf and alongshore variations and loading vertical deformation. The cross‐shelf root‐mean‐square differences between observations and predictions are 30 cm for surge height, 2 m for significant wave height, and 4 m/s for wind speed, with significant biases. The different wind forcing mainly causes the predicted height differences. The smallest standard deviation difference between observed and predicted vertical displacements is from HyFlux2 forced by DWD wind, with a 52% reduction in the standard deviation by subtracting prediction from observations. The GPS network monitors the anticlockwise surge path with maximum land subsidence of 3–5 cm. The tide gauge network monitors both the anticlockwise path of the external wave and the surge associated with strong northwesterly winds.
Intraplate rotational deformation induced by faults
Authors: Dembo Neta , Hamiel Yariv , Granot Roi
Published: October 2015

Vertical axis rotations provide important constraints on the tectonic history of plate boundaries. Geodetic measurements can be used to calculate interseismic rotations, whereas paleomagnetic remanence directions provide constraints on the long‐term rotations accumulated over geological timescales. Here we present a new mechanical modeling approach that links between intraplate deformational patterns of these timescales. We construct mechanical models of active faults at their locked state to simulate the presumed to be elastic interseismic deformation rate observed by GPS measurements. We then apply a slip to the faults above the locking depth to simulate the long‐term deformation of the crust from which we derive the accumulated rotations. We test this approach in northern Israel along the Dead Sea Fault and Carmel‐Gilboa fault system. We use 12 years of interseismic GPS measurements to constrain a slip model of the major faults found in this region. Next, we compare the modeled rotations against long‐term rotations determined based on new primary magnetic remanence directions from 29 sites with known age. The distributional pattern of site mean declinations is in general agreement with the vertical axis rotations predicted by the mechanical model, both showing anomalously high rotations near fault tips and bending points. Overall, the results from northern Israel validate the effectiveness of our approach and indicate that rotations induced by motion along faults may act in parallel (or alone) to rigid block rotations. Finally, the new suggested method unravels important insights on the evolution (timing, magnitude, and style) of deformation along major faults.
Tectonic expression of an active slab tear from high‐resolution seismic and bathymetric data offshore Sicily (Ionian Sea)
Authors: Gutscher Marc‐André , Dominguez Stephane , de Lepinay Bernard Mercier , Pinheiro Luis , Gallais Flora , Babonneau Nathalie , Cattaneo Antonio , Le Faou Yann , Barreca Giovanni , Micallef Aaron , Rovere Marzia
Published: October 2015

Subduction of a narrow slab of oceanic lithosphere beneath a tightly curved orogenic arc requires the presence of at least one lithospheric scale tear fault. While the Calabrian subduction beneath southern Italy is considered to be the type example of this geodynamic setting, the geometry, kinematics and surface expression of the associated lateral, slab tear fault offshore eastern Sicily remain controversial. Results from a new marine geophysical survey conducted in the Ionian Sea, using high‐resolution bathymetry and seismic profiling reveal active faulting at the seafloor within a 140 km long, two‐branched fault system near Alfeo Seamount. The previously unidentified 60 km long NW trending North Alfeo Fault system shows primarily strike‐slip kinematics as indicated by the morphology and steep‐dipping transpressional and transtensional faults. Available earthquake focal mechanisms indicate dextral strike‐slip motion along this fault segment. The 80 km long SSE trending South Alfeo fault system is expressed by one or two steeply dipping normal faults, bounding the western side of a 500+ m thick, 5 km wide, elongate, syntectonic Plio‐Quaternary sedimentary basin. Both branches of the fault system are mechanically capable of generating magnitude 6–7 earthquakes like those that struck eastern Sicily in 1169, 1542, and 1693.
Cellular and Mitochondrial Dual‐Targeted Organic Dots with Aggregation‐Induced Emission Characteristics for Image‐Guided Photodynamic Therapy
Authors: Feng Guangxue , Qin Wei , Hu Qinglian , Tang Ben Zhong , Liu Bin
Published: October 2015

Targeted delivery of drugs toward mitochondria of specific cancer cells dramatically improves therapy efficiencies especially for photodynamic therapy (PDT), as reactive oxygen species (ROS) are short in lifetime and small in radius of action. Different from chemical modification, nanotechnology has been serving as a simple and nonchemical approach to deliver drugs to cells of interest or specific organelles, such as mitochondria, but there have been limited examples of dual‐targeted delivery for both cells and mitochondria. Here, cellular and mitochondrial dual‐targeted organic dots for image‐guided PDT are reported based on a fluorogen with aggregation‐induced emission (AIEgen) characteristics. The AIEgen possesses enhanced red fluorescence and efficient ROS production in aggregated states. The AIE dot surfaces are functionalized with folate and triphenylphosphine, which can selectively internalize into folate‐receptor (FR) positive cancer cells, and subsequently accumulate at mitochondria. The direct ROS generation at mitochondria sites is found to depolarize mitochondrial membrane, affect cell migration, and lead to cell apoptosis and death with enhanced PDT effects as compared to ROS generated randomly in cytoplasm. This report demonstrates a simple and general nanocarrier approach for cellular and mitochondrial dual‐targeted PDT, which opens new opportunities for dual‐targeted delivery and therapy.
Versatile (Pentamethylcyclopentadienyl)rhodium‐2,2′‐Bipyridine (Cp*Rh‐bpy) Catalyst for Transfer Hydrogenation of N‐Heterocycles in Water
Authors: Zhang Lingjuan , Qiu Ruiying , Xue Xiao , Pan Yixiao , Xu Conghui , Li Huanrong , Xu Lijin
Published: October 2015

An investigation employing the catalytic system consisting of (pentamethylcyclopentadienyl)rhodium dichloride dimer [Cp*RhCl2]2 and 2,2′‐bipyridine (bpy) for transfer hydrogenation of a variety of quinoxalines, quinoxalinones, quinolines and indoles under aqueous conditions with formate as the hydrogen source is reported. This approach provides various tetrahydroquinoxalines, dihydroquinoxalinones, tetrahydroquinolines and indolines in good to excellent yields. The activity of the catalyst towards quinoxalines and quinoxalinones is excellent, with a substrate to catalyst ratio (S/C) of 10000 being feasible. The choice of ligand is critical to the catalysis, and the aqueous phase reduction is shown to be highly pH‐dependent, with acidic pH values needed for optimal reduction. The catalyst is easy to access, and the reaction is operationally simple without requiring an inert atmosphere.

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Dynamic Stereochemistry of Monobridged Tetraarylethene Naphthologues. Variations of Bistricyclic Aromatic Enes
Authors: Assadi Naela , Pogodin Sergey , Agranat Israel
Published: October 2015

Dynamic 1H NMR experiments on monobridged tetraarylethenes (bistricyclic aromatic enes devoid of one bridge, BAE‐1s) revealed the conformational processes in 13–15 (BAE‐1 s, X=S, Se, and Te) and in their respective thiiranes. The experimental energy barriers ΔG≠c were found to be 59.0, 72.2, and 67.9 kJ mol−1 for 13, 14, and 15, and 63.4, 64.4, and 61.3 kJ mol−1 for 26, 27, and 28, respectively. In contrast to the bis(α‐naphthyl) derivatives 13–15, no dynamic processes were detected for the bis(β‐naphthyl) derivatives 16–20. These results are in agreement with the mechanisms of enantiomerization of 13–15 derived from DFT calculations. The folded‐twisted global minima conformers of 13–15 undergo enantiomerization via inversion of the central ring, accompanied by rotation of the α‐naphthyl substituents. The B3LYP/SDD free energy barriers, ΔG298, for the enantiomerizations of BAE‐1s 13–15 are 57.4, 66.6, and 80.2 kJ mol−1, respectively. The minima and transition‐state conformations are chiral and the enantiomerization may proceed via chiral pathways.
Nichtkonjugierte Polymerpunkte ohne Fluorophoreinheiten mit gesteigerter Emission durch Vernetzung
Authors: Zhu Shoujun , Song Yubin , Shao Jieren , Zhao Xiaohuan , Yang Bai
Published: October 2015

Nichtkonjugierte Polymerpunkte (NCPDs) werden als neuartiges fluoreszierendes Material vorgestellt. Die NCPDs enthalten anstelle typischer konjugierter fluorophorer Gruppen nur Sub‐Fluorophore (das sind Gruppen wie CO, CN, NO), und daher sollten diese Materialien keine starke Photolumineszenz (PL) im herkömmlichen Sinne aufweisen. Allerdings kann die PL dieser Sub‐Fluorophore durch chemische Vernetzung oder physikalische Immobilisierung von Polymerketten verstärkt werden. Dieser Effekt wird als gesteigerte Emission durch Vernetzung (CEE) bezeichnet. Außerdem kann CEE über kovalente Bindungen, über Aggregation zu einer starren Struktur und über supramolekulare Wechselwirkungen bei NCPDs realisiert werden. Synthesestrategien, optische Eigenschaften und die Aussichten von NCPDs auf Gebieten wie biologische Bildgebung und Wirkstofftransport werden erörtert.
A Mini‐Twister Variant and Impact of Residues/Cations on the Phosphodiester Cleavage of this Ribozyme Class
Authors: Košutić Marija , Neuner Sandro , Ren Aiming , Flür Sara , Wunderlich Christoph , Mairhofer Elisabeth , Vušurović Nikola , Seikowski Jan , Breuker Kathrin , Höbartner Claudia , Patel Dinshaw J. , Kreutz Christoph , Micura Ronald
Published: October 2015

Nucleolytic ribozymes catalyze site‐specific cleavage of their phosphodiester backbones. A minimal version of the twister ribozyme is reported that lacks the phylogenetically conserved stem P1 while retaining wild‐type activity. Atomic mutagenesis revealed that nitrogen atoms N1 and N3 of the adenine‐6 at the cleavage site are indispensable for cleavage. By NMR spectroscopy, a pKa value of 5.1 was determined for a 13C2‐labeled adenine at this position in the twister ribozyme, which is significantly shifted compared to the pKa of the same adenine in the substrate alone. This finding pinpoints at a potential role for adenine‐6 in the catalytic mechanism besides the previously identified invariant guanine‐48 and a Mg2+ ion, both of which are directly coordinated to the non‐bridging oxygen atoms of the scissile phosphate; for the latter, additional evidence stems from the observation that Mn2+ or Cd2+ accelerated cleavage of phosphorothioate substrates. The relevance of this metal ion binding site is further emphasized by a new 2.6 Å X‐ray structure of a 2′‐OCH3‐U5 modified twister ribozyme.
Kristallstruktur einer pflanzlichen Tyrosinase aus Walnussblättern: die Bedeutung “substratlenkender Aminosäurereste” für die Enzymspezifität
Authors: Bijelic Aleksandar , Pretzler Matthias , Molitor Christian , Zekiri Florime , Rompel Annette
Published: October 2015

Tyrosinasen und Catecholoxidasen gehören zur Klasse der Typ‐III‐Kupferenzyme. Forscher arbeiten seit Jahrzehnten daran, die Monophenolase‐/Diphenolase‐Spezifität dieser Enzyme auf struktureller Ebene zu erklären und entwickelten dazu eine Hypothese (basierend auf der ersten Catechol‐ und Tyrosinasestruktur), der zufolge der Grund für das Fehlen von Monophenolase‐Aktivität in Catecholoxidasen das strukturell eingeschränkte aktive Zentrum sein könnte. Jüngste strukturelle und biochemische Studien an dieser Enzymklasse liefern jedoch Anlass zu Zweifeln an dieser Theorie. Hier wird die erste Kristallstruktur einer pflanzlichen Tyrosinase (Juglans regia) präsentiert, anhand derer gezeigt wird, dass die Unterscheidung zwischen Mono‐ und Diphenolase‐Aktivität auf struktureller Ebene nicht durch eine strukturelle Einschränkung des aktiven Zentrums bestimmt wird; vielmehr spielen Aminosäuren, die sich am Eingang zu und innerhalb der zweiten Schale um das aktive Zentrum befinden, eine viel wichtigere Rolle, als bisher angenommen.
Trapping N2 and CO2 on the Sub‐Nano Scale in the Confined Internal Spaces of Open‐Cage C60 Derivatives: Isolation and Structural Characterization of the Host–Guest Complexes
Authors: Futagoishi Tsukasa , Murata Michihisa , Wakamiya Atsushi , Murata Yasujiro
Published: October 2015

An open‐cage C60 tetraketone with a large opening was able to encapsulate N2 and CO2 molecules after its exposure to high pressures of N2 and CO2 gas. A subsequent selective reduction of one of the four carbonyl groups on the rim of the opening induced a contraction of the opening (→2) and trapped the guest molecules inside 2. The thus‐obtained host–guest complexes N2@2 and CO2@2 could be isolated by recycling HPLC, and were found to be stable at room temperature. The molecular structures of N2@2 and CO2@2 were determined by single‐crystal X‐ray diffraction analyses, and revealed a short NN triple bond for the encapsulated N2, as well as an unsymmetric molecular structure for the encapsulated molecule of CO2. The IR spectrum of CO2@2 suggested that the rotation of the encapsulated molecule of CO2 is partially restricted, which was supported by DFT calculations.
Detection of Circularly Polarized Luminescence of a Cs‐EuIII Complex in Raman Optical Activity Experiments
Authors: Wu Tao , Kapitán Josef , Mašek Vlastimil , Bouř Petr
Published: October 2015

Circularly polarized luminescence (CPL) spectra are extremely sensitive to molecular structure. However, conventional CPL measurements are difficult and require expensive instrumentation. As an alternative, we explore CPL using Raman scattering and Raman optical activity (ROA) spectroscopy. The cesium tetrakis(3‐heptafluoro‐butylryl‐(+)‐camphorato) europium(III) complex was chosen as a model as it is known to exhibit very large CPL dissymmetry ratio. The fluorescent bands could be discriminated from true Raman signals by comparison of spectra acquired with different laser excitation wavelengths. Furthermore, the ROA technique enables fluorescence identification by measuring the degree of circularity. The CPL dissymmetry ratio was measured as the ROA circular intensity difference of 0.71, the largest one ever reported. The alternative CPL measurement enhances applications of lanthanides in analytical chemistry and chemical imaging of biological objects.
Synthesis and Functional Reconstitution of Light‐Harvesting Complex II into Polymeric Membrane Architectures
Authors: Zapf Thomas , Tan Cherng‐Wen Darren , Reinelt Tobias , Huber Christoph , Shaohua Ding , Geifman‐Shochat Susana , Paulsen Harald , Sinner Eva‐Kathrin
Published: October 2015

One of most important processes in nature is the harvesting and dissipation of solar energy with the help of light‐harvesting complex II (LHCII). This protein, along with its associated pigments, is the main solar‐energy collector in higher plants. We aimed to generate stable, highly controllable, and sustainable polymer‐based membrane systems containing LHCII–pigment complexes ready for light harvesting. LHCII was produced by cell‐free protein synthesis based on wheat‐germ extract, and the successful integration of LHCII and its pigments into different membrane architectures was monitored. The unidirectionality of LHCII insertion was investigated by protease digestion assays. Fluorescence measurements indicated chlorophyll integration in the presence of LHCII in spherical as well as planar bilayer architectures. Surface plasmon enhanced fluorescence spectroscopy (SPFS) was used to reveal energy transfer from chlorophyll b to chlorophyll a, which indicates native folding of the LHCII proteins.
A Visible‐Light‐Mediated Radical Smiles Rearrangement and its Application to the Synthesis of a Difluoro‐Substituted Spirocyclic ORL‐1 Antagonist
Authors: Douglas James J. , Albright Haley , Sevrin Martin J. , Cole Kevin P. , Stephenson Corey R. J.
Published: October 2015

A visible‐light‐mediated radical Smiles rearrangement has been developed to address the challenging synthesis of the gem‐difluoro group present in an opioid receptor‐like 1 (ORL‐1) antagonist that is currently in development for the treatment of depression and/or obesity. This method enables the direct and efficient introduction of the difluoroethanol motif into a range of aryl and heteroaryl systems, representing a new disconnection for the synthesis of this versatile moiety. When applied to the target compound, the photochemical step could be conducted on 15 g scale using industrially relevant [Ru(bpy)3Cl2] catalyst loadings of 0.01 mol %. This transformation is part of an overall five‐step route to the antagonist that compares favorably to the current synthetic sequence and demonstrates, in this specific case, a clear strategic benefit of photocatalysis.
Combining a Nitrogenase Scaffold and a Synthetic Compound into an Artificial Enzyme
Authors: Tanifuji Kazuki , Lee Chi Chung , Ohki Yasuhiro , Tatsumi Kazuyuki , Hu Yilin , Ribbe Markus W.
Published: October 2015

Nitrogenase catalyzes substrate reduction at its cofactor center ([(Cit)MoFe7S9C]n−; designated M‐cluster). Here, we report the formation of an artificial, nitrogenase‐mimicking enzyme upon insertion of a synthetic model complex ([Fe6S9(SEt)2]4−; designated Fe6RHH) into the catalytic component of nitrogenase (designated NifDKapo). Two Fe6RHH clusters were inserted into NifDKapo, rendering the conformation of the resultant protein (designated NifDKFe) similar to the one upon insertion of native M‐clusters. NifDKFe can work together with the reductase component of nitrogenase to reduce C2H2 in an ATP‐dependent reaction. It can also act as an enzyme on its own in the presence of EuIIDTPA, displaying a strong activity in C2H2 reduction while demonstrating an ability to reduce CN− to C1–C3 hydrocarbons in an ATP‐independent manner. The successful outcome of this work provides the proof of concept and underlying principles for continued search of novel enzymatic activities based on this approach.
Synthetic Origin of Tramadol in the Environment
Authors: Kusari Souvik , Tatsimo Simplice Joel N. , Zühlke Sebastian , Spiteller Michael
Published: October 2015

The presence of tramadol in roots of Sarcocephalus latifolius trees in Northern Cameroon was recently attributed to point contamination with the synthetic compound. The synthetic origin of tramadol in the environment has now been unambiguously confirmed. Tramadol samples isolated from tramadol pills bought at a street market in downtown Maroua and highly contaminated soil at Houdouvou were analyzed by high‐precision 14C measurements by accelerator mass spectrometry (14C AMS): Tramadol from the pills did not contain any radiocarbon, thus indicating that it had been synthesized from 14C‐free petroleum‐derived precursors. Crucially, tramadol isolated from the soil was also radiocarbon‐free. As all biosynthetic plant compounds must contain radiocarbon levels close to that of the contemporary environment, these results thus confirm that tramadol isolated from the soil cannot be plant‐derived. Analyses of S. latifolius seeds, in vitro grown plants, plants from different origins, and stable‐isotope labeling experiments further confirmed that synthetic tramadol contaminates the environment.