bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on electromigration in flip chip lead-free solder connections with 40 μm or 30 μm diameter on thin film ceramic substrates
Authors: Gorywoda Marek , Dohle Rainer , Kandler Bernd , Burger Bernd
Published: November 2015

Electromigration comprises one of the processes affecting the long-term reliability of electronic devices; it has therefore been the focus of many investigations in recent years. In regards to flip chip packaging technology, the majority of published data is concerned with electromigration in solder connections to metallized organic substrates. Hardly any information is available in the literature on electromigration in lead-free solder connections on thin film ceramic substrates.

This work presents results of a study of electromigration in lead-free (SAC305) flip chip solder bumps with a nominal diameter of 40 μm or 30 μm with a pitch of 100 μm on silicon chips assembled onto thin film Al2O3 ceramic substrates. The under bump metallization (UBM) comprised of a 5 μm thick electroless nickel immersion gold (ENIG) layer directly deposited on the AlCu0.5 trace. The ceramic substrates were metallized using a thin film multilayer (NiCr-Au(1.5 μm)-Ni(2 μm) structure on the top of which wettable areas were produced with high precision by depositing flash Au (60 nm) of the required diameter (40 μm or 30 μm).

All electromigration tests were performed at the temperature of 125 °C. Initially, one chip assembly with 40 μm and one with 30 μm solder bumps was loaded with the current density of 8 kA/cm2 for 1,000 h. The assemblies did not fail and an investigation with SEM revealed no significant changes to the microstructure of the bumps. Thereafter seven chip assemblies with 40 μm solder bumps and five assemblies with 30 μm bumps were subjected to electromigration tests of 14 kA/cm2 or 25 kA/cm2, respectively. Six of the 40 μm-assemblies failed after 7,000 h and none of the 30 μm-assemblies failed after 2,500 h of test duration so far. Investigation of failed samples performed with SEM and EDX showed asymmetric changes of microstructure in respect to current flow. Several intermetallic phases were found to form in the solder. The predominant damage of the interconnects was found to occur at the cathode contact to chip; the Ni-P layers there showed typical columnar Kirkendall voids caused by migration of Ni from the layers into the solder. Failure of the contacts apparently occurred at the interface between Ni-P and solder.

In summary, the results of the study indicate a very high stability of lead-free solder connections on ceramic substrates against electromigration. This high stability is primarily due to a better heat dissipation and thus to a relatively low temperature increase of the ceramic packages caused by resistive heating during flow of electric current. In addition, the type of the metallization used in the study seems to be more resistant to electromigration than the standard PCB metallization as it does not contain a copper layer.
Flex-DIMM – A New High Density Module Form Factor
Authors: Clayton James E.
Published: November 2015

The Dual In-Line Memory Module (DIMM) has remained relatively unchanged for the past two decades, with exception of an increase in PCB size, I/O pads and layer count. A new generation called Flex-DIMM is introduced by replacing the rigid-PCB substrate with a thin, bifurcated, flexible circuit that enables several improvements; including a thinner cross-section, better signal integrity with lower layer count, better thermal dissipation and ability to be directly mated to the surface of a motherboard. Originally intended for RDIMM applications, the new module may be an ideal solution for clustered microservers.
High Performance High Density Interconnects using Liquid Crystal Polymer-Substrates, Circuits Driven by Mobile Applications
Authors: Rathburn James
Published: November 2015

The goal of the development effort was to prove a new way of creating electrical interconnects that enable much higher density, tuned circuits and connectors driven by the demands of future mobile and computing applications, including wearable and connected devices. The primary results obtained are a method to fabricate package substrates, small form factor rigid and flexible circuits using a material used in the connector industry Liquid Crystal Polymer, and linking circuits and connectors with tuned high density performance not possible with legacy manufacturing. Applications will be detailed in conjunction with the Semiconductor companies that demonstrate substrates and circuits that have high aspect ratio traces with 20–50 micron traces surrounded with fusion bonded LCP that enables impedance matching of 1–2% on high density. The study extends further to connector technology that enables interconnect of the subject substrate or circuit directly into mobile and wearable applications with over 1000 high speed interconnects capable of 28–56 Gb/s performance within a 1/2 inch square area. In addition the study will leverage the formable nature of circuit bearing Liquid Crystal Polymer to create interconnected assemblies with integral antennae, decoupling, RF shielding and die to die interconnect ideal for wearable applications.
Impact of Metallurgical and Mechanical Properties of Sintered Silver Nanoparticles on Die-attach Reliability of High-temperature Power Modules
Authors: Tatsumi Hiroaki , Kumada Sho , Fukuda Atsushi , Yamaguchi Hiroshi , Kashiba Yoshihiro
Published: November 2015

Sintered silver bonding processes are expected to offer bonding solutions with high heat resistances for power modules using wide-bandgap semiconductors. This study reports the die-attach reliability of such a bonding process under thermal cycling tests, focusing on the metallurgical and mechanical properties of sintered silver nanoparticles. A nanocrystalline structure with a grain size of approximately 150 nm was observed in the as-sintered state, while a coarsened structure with a grain size of several microns and pore coalescence was observed after annealing at 623 K for 1 h. In addition, the increase of bonding pressure reduced the number of coarse pores. Observations with a transmission electron microscope showed favorable crystalline structure along the grain boundaries. Tensile tests at room and high temperature revealed that the sintered silver nanoparticles showed the inherent mechanical properties of nanocrystalline metals. Thermal cycling tests of die-attached specimens demonstrated the temperature dependence of crack propagation caused by plastic deformation at a constant temperature amplitude. Furthermore, pore coalescence and coarsening reduced bonding reliability. It can be inferred from the results that nanocrystalline structure and minute pore dispersion improves bonding reliability.
Barrier Properties of Electroless Ni-B UBM for Solder Joining
Authors: Morita Masaru , Akamatsu Toshiya , Imaizumi Nobuhiro , Sakuyama Seiki
Published: November 2015

As demands accelerate for high density, high speed transmission and low power integrated circuits, 3D-ICs with through-silicon via (TSV) is pursued. In the structure of 3D-ICs, the first die is attached to the second die with micro bump, and the second die is attached to the circuit substrate with a C4 solder bump. The electrode structure of the second die is Cu/Ni UBM. The stress of the Ni-B layer is less than that of the Ni-P layer, and the Ni-B layer can suppress stress and die warpage. The purposes of our study are to clarify the difference in the barrier properties of the Ni-B UBM and Ni-P under bump metal (UBM) and the relevance of the barrier properties of Ni UBM and intermetallic compound (IMC) growth. It was found that an electroless Ni-B plating layer is superior to a Ni-P plating layer for UBM in liquid phase diffusion and in solid phase diffusion, and that a segregated B layer is formed under the IMC layer of a Ni-B land due to reflow soldering. It was estimated that this B layer plays the role of being a barrier layer for solder diffusion.
2.5D Smart Objects Using Thermoplastic Stretchable Interconnects
Authors: Plovie Bart , Dunphy Sheila , Dhaenens Kristof , Van Put Steven , Vandecasteele Bjorn , Bossuyt Frederick , Vanfleteren Jan
Published: November 2015

This contribution describes the technology used to produce thermoplastically deformable electronics, based on flexible circuit board technology, to achieve low-cost 2.5D free-form rigid smart objects. These one-time deformable circuits employ a modified version of the previously developed meander-based “polymer-last” technology for dynamically stretchable elastic circuits. This is readily achieved by substituting the dynamically stretchable elastomeric materials (e.g. silicone) with thermoplastic polymers (e.g. polycarbonate). Afterwards the circuit is given its final form using widely available thermoforming techniques, such as vacuum forming, where the material is heated above its glass transition temperature and drawn against a forming tool by a strong vacuum. After cooling down the thermoplastic retains its shape without inducing large internal stresses. The presented method allows for the production of these circuits on a flat substrate, using standard printed circuit board production equipment, with deformation only taking place afterwards; eliminating the need for large investments and reducing the cost of fabrication. Potential advantages over competitive methods are reductions in weight and material usage, decrease of mechanical complexity; lower tooling cost, increased resilience, and a higher degree of manufacturer independence due to adhering to standard industrial practices. This is realized by starting production from a flexible circuit board, manufactured by an industrial supplier using polyimide flexible copper clad laminate, which is attached to a temporary reusable carrier board through means of a silicone based high-temperature pressure sensitive adhesive. Through selective laser structuring the meander and island outlines of the flexible circuit are defined, without causing damage to the carrier board or pressure sensitive adhesive. After removing the residual material the circuit is assembled using high-temperature lead-free solder, made possible by the temporary carrier keeping the circuit in place at these elevated temperatures. The circuit is then transferred into a thermoplastic laminate, which is deformed into its final shape. After demonstrating the need for stretchable electronics for this application, this contribution describes the method used to design, fabricate, and test the first one-time deformable circuits manufactured using the presented technology. Using the initial set of observations a series of preliminary design rules is established, both for the circuit and choice of materials. The feasibility of this manufacturing method was then demonstrated through a small scale production run using lab scale equipment, where a large quantity of high power LEDs was integrated into a one-time deformable device made out of polystyrene and thermoplastic polyurethane. These devices were then tested by exposing them to real world conditions for several days.
L/S ≤ 5/5μm Line Embedded Organic Substrate Manufacturing for 2.1D/2.5D SiP Application
Authors: Chen Yu-Hua , Cheng Shyh-Lian , Hu Dyi-Chung , Tseng Tzvy-Jang
Published: November 2015

The requirement for IC packages with higher density interconnection with fine line feature has increased significantly recently. Current organic substrates are limited to line/space 8/8μm for Semi-additive Process(SAP), and it will cause yield loss from adhesion issue of line/space less than 5/5μm. But the impact of bad adhesion of fine line is very small in laser embedded (LE) substrate because of its embedded structure. There are several advantages of LE such as the capacity of stereo copper features and better electric performance with lower variation of trench width/depth. It can form fine pitch trench line/space even less than 3/3μm. It also can provide better design flexibility for its pad-less features and better reliability than SAP process.

In this paper, we will discuss the key of the processes and demonstrate the fabrication of fine line substrate of 3/3μm line/space by fine tuning line embedded technology. Line embedded trace was made by laser direct ablation (LDA) on organic build-up dielectric material with fine filler size. Laser ablation process capability shows excellent trench depth and shape control. In order to get better copper thickness uniformity, novel uniformity copper plating technology on via, pad and trench has developed. Low cost and uniformity copper reduction process has also been evaluated and developed.
Packaging Tradeoff for SIP Integration Targeting High Speed PAM-4 Applications
Authors: Haentjens B , Desruelles G , Chrétien G , Leborgne A , Haentjens Y , Dupuy J , Jorge F , Konczykowska A , Beauvisage I , Delleme R , Martin D , Bila S , Frigui K , Ngoho S , Frigui B , Mardoyan H
Published: November 2015

High speed transmission systems using optical fiber are now focusing on 4-level PAM (Pulse Amplitude Modulation) format. This is requesting ultra-wideband electronic system in package, with a high phase linearity behavior in order to drive the electro-optical modulators. Moreover, new power DAC (Digital to Analog Converter) dies, are now available to generate up to 56 GBd, 4-level PAM signals, and providing 4Vpp of differential output amplitude swing. High frequency studies have been pursued to provide system integration in a BGA (Ball Grid Array) package. The BGA package transitions optimization and the configuration of multi-lines carriers, becomes a key step in the design flow. In this paper, some steps of the design, manufacturing process of the SIP (System In Package) and its demonstration board are proposed. The choices of the package, the thermal management, the clock management function are studied according to the final environmental constraint of the SIP. The data lines phase skew are analyzed with the support of EM (Electro Magnetic) simulations to better understand the potential impact on the output eye. Finally, the BGA package transition, simulated and measured results are compared, from DC up to 40 GHz and the measured SIP output, 4 levels, 56GBps eye diagram is presented.
Cretaceous rocks in the region of Liard and Mackenzie rivers, Northwest Territories
Authors: Stott D F
Published: November 2015

Cretaceous rocks in southwestern Northwest Territories are described and their general distribution is outlined. Lower Cretaceous rocks, all of Albian age and of marine origin, are included in the Fort St. John group which is divided into three formations. The
Buckmghorse formation comprises basal conglomerate and sandstone and a thick succession of sideritic shale. The overlying Sikanni formation, restricted from its original definitions, contains glauconitic sandstone and siltstone. At the top, the newly defined Sully formation includes siderite and
gypsiferous shales, which are equivalent to rocks previously included by original definitions in the Sikanni formation. Upper Cretaceous rocks a redivided into the Fort Nelson, Kotaneelee, and Wapiti formations. The Fort Nelson formation, lying conformably on the Fort St. John group, is probably of
Cenomanian age and consists of massive conglomerate and coarse-grained sandstone. No Turonian sediments are known in this region. The Kotaneelee formation, containing fossils of Santonian age, includes sideritic shale, some sandstone, and sandy glauconitic mudstone. The Wapiti formation contains
coal, non-marine sandstone and shale.
Carboniferous biostratigraphy and correlation, northeastern British Columbia and southwestern District of Mackenzie
Authors: Bamber E W , Mamet B L
Published: November 2015

Regional stratigraphic and fauna distribution data from 5 surface stratigraphic sections and 37 subsurface sections indicate the following ages and stratigraphic relationships within the Lower Carboniferous succession of the area. The Banff Formation (Early? and
Middle Tournaisian, Plains), which consists of shale with minor amounts of siltstone and limestone, passes westward into equivalent shale and chert of the Besa River Formation. The Pekisko Formation (Middle Tournaisian, Plains), composed of skeletal limestone and wackestone, and the "Shunda''
Formation (Late Tournaisian, Plains), comprising argillaceous limestone, calcareous shale and minor amounts of skeletal and pelletoid limestone, change facies westward, near the eastern edge of the disturbed belt, into the upper Besa River Formation and Member A of the Prophet Formation, and are
equivalent to the upper Clausen and lower Flett formations to the north (southern Mackenzie Mountains). The lower member of the Debolt Formation (Early and Early Middle Visean, Plains), composed of micritic and skeletal limestone, wackestone and calcareous shale, grades westward into the cherty
dolomite and limestone of Member B of the Prophet Formation and is correlated with the limestone and calcareous shale of the middle Flett Formation. The upper member of the Debolt Formation (Late Middle and Early Late Yisean, Plains) consists of pelletoid, micritic, argillaceous and skeletal
limestone with minor amounts of calcareous shale and dolomite, and is correlative with the cherty, skeletal limestone of Member C and the upper part of Member B of the Prophet Formation, and with the skeletal limestone and calcareous shale of the upper Flett Formation. The cherty carbonates of the
Prophet Formation(Late? Tournaisian to Early Late Yisean) occur in the outcrop belt and westernmost plains of northeastern British Columbia and change facies into the Besa River Formation by a progressive increase in shale and chert from base to top toward the west. The Stoddart Group (Early Late Vi
sean to Pennsylvanian), which consists of terrigenous elastics and carbonates, occurs in the plains and outcrop belt of northeastern British Columbia, and grades northward into the coarse-grained, partly continental elastics of the Mattson Formation, and westward into the shale of the Besa River
Formation. Eleven Middle Tournaisian to Late Yisean foraminiferal zones within the area correspond to zones previously established for the North American Cordillera, and correlate with the original Lower Carboniferous stratigraphic sequence of Eurasia. There is a consistent relationship between the
vertical and lateral distribution of foraminiferal zones and associated macro faunal assemblages. With minor exceptions, the combined fauna succession of this area matches that in southwestern Alberta and western United States and forms part of a consistent biostratigraphic scheme applicable to
Lower Carboniferous rocks throughout western North America.
Isostatic and enhanced isostatic gravity anomaly maps of the Arctic
Authors: Sobczak L W , Halpenny J F
Published: November 2015

Isostatic and enhanced isostatic gravity anomaly maps have been developed as aids for the interpretation of gravity anomalies with respect to geology. Isostatic gravity anomalies in the Arctic display topographic correlations which have been removed to produce a
new type of gravity anomaly map - an enhanced isostatic map. This map enhances local, short-wavelength variations in gravity related to geological structures and eliminates those long-wavelength variations related to topographic, thermal and glacial effects. An enhanced isostatic anomaly map readily
outlines active (tectonic) and inactive (stable) areas which can reflect the hydrocarbon potential of a sedimentary basin and indicates regions of young (usually  JOO Ma) continental crust.
An interdisciplinary investigation into the narratives of three co-researchers: A postfoundational notion of practical theology
Authors: Meyer Juanita
Published: November 2015

This article elaborates on the sixth movement of a postfoundational notion of practical theology and is concerned with giving a description of experiences, which are thickened through interdisciplinary investigation. The experiences of interest are those of the co-researchers who formed part of the larger research study, conducted in 2010, and who were at the time adolescent male orphans, affected by HIV and AIDS, poverty and father abandonment. The research was conducted within the theoretical frameworks of a postfoundational notion of practical theology, narrative therapy and research, and social constructionism. A qualitative research strategy was employed, with the case study design as point of departure in collecting and analysing research data. Various key aspects were investigated with the use of the model of narrative and the seven movements of a postfoundational notion of practical theology. The aim of this article is to provide an illustration of the application of the principles of a postfoundational notion of practical theology, and its sixth movement – an interdisciplinary investigation – as it is applied within this specific research context. Four interdisciplinary conversationalists, each from a different academic field, were invited to reflect on the three narrated stories of the co-researchers. This article, then, gives a report on their feedback and the value of interdisciplinary investigation in aiding, with the understanding of the meaningmaking process behind collected narratives.
Glioblastoma Stem Cells as a New Therapeutic Target for Glioblastoma
Authors: Kalkan Rasime
Published: November 2015

Primary and secondary glioblastomas (GBMs) are two distinct diseases. The genetic and epigenetic background of these tumors is highly variable. The treatment procedure for these tumors is often unsuccessful because of the cellular heterogeneity and intrinsic ability of the tumor cells to invade healthy tissues. The fatal outcome of these tumors promotes researchers to find out new markers associated with the prognosis and treatment planning. In this communication, the role of glioblastoma stem cells in tumor progression and the malignant behavior of GBMs are summarized with attention to the signaling pathways and molecular regulators that are involved in maintaining the glioblastoma stem cell phenotype. A better understanding of these stem cell-like cells is necessary for designing new effective treatments and developing novel molecular strategies to target glioblastoma stem cells. We discuss hypoxia as a new therapeutic target for GBM. We focus on the inhibition of signaling pathways, which are associated with the hypoxia-mediated maintenance of glioblastoma stem cells, and the knockdown of hypoxia-inducible factors, which could be identified as attractive molecular target approaches for GBM therapeutics.
Percutaneous Fascia Release for Treating Chronic Recurrent Gluteal Myofascial Pain—A Pilot Study of a New Technique
Authors: Chen Hsin-Shui , Lin Ming-Ta , Hong Chang-Zern , Hsieh Yueh-Ling , Chou Li-Wei
Published: November 2015

Objective

To investigate the therapeutic effectiveness of percutaneous fascia release to treat chronic recurrent gluteal myofascial pain related to recurrent tendonitis or bursitis at the attachment sites.

Methods

Five patients (three males, two females; aged 48.6 ± 8.9 years) with myofascial trigger points in the gluteus medius muscle were treated. Outcome measures, including pain intensity, pressure pain threshold, and the relative strength of hip abduction, were assessed before, immediately after, and six months after the treatment. The data measured before and after treatment (different times) on visual analog scale, pressure pain threshold, and relative hip abduction strength were analyzed by Wilcoxon signed-rank test and paired t-test, respectively, for the comparisons between time points.

Results

Reduction in pain intensity and increase in the pressure pain threshold and the relative hip abduction strength were found in all five patients after treatment when compared with those of before treatment ( P < 0.05). Moreover, all of these improvements existed for at least six months ( P > 0.05).

Conclusions

Percutaneous fascia release of gluteal muscle insertion sites can be used to treat chronic gluteal pain related to subtrochanteric bursitis to avoid recurrence, if other treatment cannot control the recurrence, although this was demonstrated only on a small sample size without control and blind assessment in the pilot study.
Boundary values, random walks, and $\ell^p$-cohomology in degree one
Authors: Gournay Antoine
Published: November 2015

The vanishing of reduced

\ell^2

-cohomology for amenable groups can be traced to the work of Cheeger and Gromov in [10]. The subject matter here is reduced

\ell^p

-cohomology for

p \in ]1,\infty[

, particularly its vanishing. Results for the triviality of

\underline {\ell^pH}^1(G)

are obtained, for example: when

p \in ]1,2]

and

G

is amenable; when

p \in ]1,\infty[

and

G

is Liouville (e.g. of intermediate growth).

This is done by answering a question of Pansu in [34, §1.9] for graphs satisfying certain isoperimetric profile. Namely, the triviality of the reduced

\ell^p

-cohomology is equivalent to the absence of non-constant harmonic functions with gradient in

\ell^q

(

q

depends on the profile). In particular, one reduces questions of non-linear analysis (

p

-harmonic functions) to linear ones (harmonic functions with a very restrictive growth condition).
Bredon cohomological dimensions for groups acting on $\mathrm{CAT}(0)$-spaces
Authors: Degrijse Dieter , Petrosyan Nansen
Published: November 2015

Let

G

be a group acting isometrically with discrete orbits on a separable complete

\mathrm{CAT}(0)

-space of bounded topological dimension. Under certain conditions, we give upper bounds for the Bredon cohomological dimension of

G

for the families of finite and virtually cyclic subgroups. As an application, we prove that the mapping class group of any closed, connected, and orientable surface of genus

g ≥ 2

admits a

9g-8

)-dimensional classifying space with virtually cyclic stabilizers. In addition, our results apply to fundamental groups of graphs of groups and groups acting on Euclidean buildings. In particular, we show that all finitely generated linear groups of positive characteristic have a finite dimensional classifying space for proper actions and a finite dimensional classifying space for the family of virtually cyclic subgroups. We also show that every generalized Baumslag–Solitar group has a 3-dimensional model for the classifying space with virtually cyclic stabilizers.
Análisis de competencias transversales en entidades museísticas. Propuesta de una herramienta para evaluar competencias transversales en gestores museísticos.
Authors: Arguello Arciniegas Zara Marcela
Published: November 2015

En el campo de la Gestión Cultural, un mundo tan amplio y a veces tan difícil de esbozar en cuanto a todo lo que abarca, las competencias transversales cumplen un papel muy importante. Por tal motivo se ha querido proponer una herramienta para evaluar competencias trasversales en gestores culturales que desempeñen su labor profesional en museos. Se presenta una serie de competencias transversales y a continuación se elabora un listado de diez consideradas como importantes para el personal de gestión cultural de un museo. Para esto se parte, en primer lugar, de las competencias transversales propuestas por las universidades que ofrecen titulaciones oficiales de máster en Gestión Cultural en España y, en segundo lugar, de las competencias que propone el ICOM para los trabajadores de museos. Finalmente se presenta la propuesta de una herramienta para realizar la evaluación de las competencias transversales elegidas.
Recording of climate and diagenesis through fossil pigments and sedimentary DNA at Laguna Potrok Aike, Argentina
Authors: Vuillemin A. , Ariztegui D. , Leavitt P. R. , Bunting L. ,   the PASADO Science Team
Published: November 2015

Abstract. Aquatic sediments record past climatic conditions while providing a wide range of ecological niches for microorganisms. Although marine sedimentary microbial assemblages are often defined by their surrounding geochemical conditions, the influence of environmental features upon microbial development and post-depositional survival remains largely unknown in the lacustrine realm. Due to long-term microbial activity, the composition of environmental DNA can be expected to evolve with sediment depth and over time and therefore should reflect both ancient and extant microbial populations, but this hypothesis has rarely been tested using a multiproxy approach. Here geomicrobiological and phylogenetic analyses of a Patagonian maar lake were used to indicate that the different sedimentary microbial assemblages derive from specific lacustrine regimes during defined climatic periods. Two well defined climatic intervals whose sediments harboured active microbial populations and measurable ATP were sampled for a comparative environmental study based on fossil pigments and 16S rRNA gene sequences. Bacterial and archaeal 16S rRNA gene sequences recovered from the Holocene record revealed a microbial community adapted to subsaline conditions actively producing methane during organic matter degradation. These characteristics were associated with sediments resulting from endorheic lake conditions with high evaporative stress and concomitant high algal productivity. Moreover, archaeal clone libraries established throughout the Holocene record indicate an age-related stratification of these populations, consistent with a gradual use of organic substrates after deposition. In contrast, sulphate-reducing bacteria and lithotrophic Archaea were predominant in sediments dated from the Last Glacial Maximum, in which pelagic clays alternated with fine volcanic material characteristic of a lake level highstand and freshwater conditions, but reduced water column productivity. These patterns reveal that microbial assemblages identified from environmental DNA stemmed from a variety of sedimentary niches associated with climate-dependent factors (catchment inflows, water column conditions, productivity), but that initial assemblages underwent structural changes and selective preservation during early diagenesis to result in the final composition entombed in the sediments. We conclude that environmental DNA obtained from lacustrine sediments provides essential genetic information to complement paleoenvironmental indicators and trace climate change and post-depositional diagenetic processes over tens of millennia.
Concentrations and ratios of Sr, Ba and Ca along an estuarine river to the Gulf of Mexico – implication for sea level rise effects on trace metal distribution
Authors: He S. , Xu Y. J.
Published: November 2015

Abstract. Strontium and barium to calcium ratios are often used as proxies for tracking animal movement across salinity gradients. As sea level rise continues, many estuarine rivers in the world face saltwater intrusion, which may cause changes in mobility and distribution of these metals upstream. Despite intensive research on metal adsorption and desorption in marine systems, knowledge of the spatiotemporal distribution of these elements along estuarine rivers is still limited. In this study, we conducted an intensive monitoring of Sr and Ba dynamics along an 88 km long estuary, the Calcasieu River in South Louisiana, USA, which has been strongly affected by saltwater intrusion. Over the period from May 2013 to August 2015, we collected monthly water samples and performed in-situ water quality measurements at six sites from the upstream to the river mouth, with a salinity range from 0.02 to 29.50 ppt. Water samples were analyzed for Sr, Ba, and Ca concentrations. In-situ measurements were made on salinity, pH, water temperature, dissolved oxygen concentration, and specific conductance. We found that the Sr and Ca concentrations and the Sr / Ca ratio all increased significantly with increasing salinity. The average Sr concentration at the site closest to the Gulf of Mexico (site 6) was 46.21 μmol L−1, which was about 130 times higher than that of the site furthest upstream (site 1, 0.35 μmol L−1). The average Ca concentration at site 6 was 8.19 mmol L−1, which was about 60 times higher than that of site 1 (0.13 mmol L−1). The average Sr / Ca ratio at site 6 (8.41 mmol mol−1) was about 3 times the average Sr / Ca ratio at site 1 (2.89 mmol mol−1). However, the spatial variation in Ba concentration was marginal, varying from 0.36 μmol L−1 at site 6 to 0.47 at site 5. The average Ba / Ca ratio at site 1 (4.82 mmol mol−1) was about 54 times the average Ba / Ca ratio at site 6 (0.09 mmol mol−1), showing a clear negative relation between the Ba / Ca ratio and increasing salinity. All the elemental concentrations and ratios had considerable seasonal variations, with significant differences among sampling months for the Sr, Ba concentrations and the Ba / Ca ratio (p < 0.01). The results from this study suggest that concentrations of Sr and Ca in the world's estuaries will very likely increase in the future as sea level rise continues. For low-gradient estuarine rivers such as the Calcasieu River in South Louisiana, USA, water chemistry upstream would experience substantial Sr and Ca enrichment, which could affect aquatic environments and biological communities.
Cualidades corporativas en el derecho y la sociedad: un caso de los Estados Unidos
Authors: Greenhouse Carol J.
Published: November 2015

La sociedad neoliberal engloba tanto poderes estatales como no estatales, de modo tal que plantea nuevos retos interpretativos a los antropólogos y sociólogos del derecho interesados en la significación social y cultural del derecho. Desarrollo aquí un “estudio de caso” en torno a un dictamen reciente del Tribunal Supremo de los Estados Unidos en el cual esos aspectos figuran entre los temas que contempla. Examino el asunto Comisión de Elecciones Federales contra Ciudadanos Unidos [Citizens United] —un caso que implicaba el derecho de las empresas a invertir dinero en campañas electorales federales. El resultado fue altamente polémico en Estados Unidos, ya que eliminaba antiguas restricciones relativas a la inversión empresarial en la esfera política. Desde un punto de vista etnográfico, sin embargo, la relevancia del dictamen puede estar menos en lo que permite a las corporaciones decir y hacer en el contexto electoral que en el modo en que cualidades peculiares de carácter social, pretendidamente (por el Tribunal) inherentes a las empresas, son valoradas y priorizadas. Sugiero que la multiforme naturaleza de las cualidades de las empresas, tal como las define el Tribunal, apunta al significado potencial del caso para la vida cotidiana que alcanza al sentido de la propia diferenciación entre derecho y sociedad.
Naturalización de los contenidos y objetivos de aprendizaje: acerca del énfasis que los futuros maestros de primaria ponen en los aspectos técnico-pedagógicos
Authors: Cárcamo Vásquez Héctor
Published: November 2015

El objetivo de este artículo es reconocer las condiciones que propician la naturalización de los contenidos a enseñar por parte de los futuros profesores de educación primaria. La metodología empleada corresponde a la cualitativa con enfoque etnográfico. Para la recogida de datos se utilizó la revisión documental y la entrevista en profundidad. La investigación se realizó en la ciudad de Madrid, específicamente el área de estudio estuvo conformada por dos universidades públicas y dos universidades privadas. La investigación se inició el año 2010 y finalizó a mediados de 2013. Los resultados obtenidos nos permiten plantear que lo que prima en el contexto de la formación inicial del profesorado de educación primaria y, muy probablemente, durante los primeros años de la carrera docente es una lógica instrumental cuyo reflejo más claro se encuentra en la hegemonía de una ‘tecnología instruccional’ dentro de los espacios escolares, sean del nivel que sean.
The Impact of Hands-On-Approach on Student Academic Performance in Basic Science and Mathematics
Authors: O. Ekwueme Cecilia , E. Ekon Esther , C. Ezenwa-Nebife Dorothy
Published: November 2015

Children can learn mathematics and sciences effectively even before being exposed to formal school curriculum if basic Mathematics and Sciences concepts are communicated to them early using activity oriented (Hands-on) method of teaching. Mathematics and Science are practical and activity oriented and can best be learnt through inquiry (Okebukola in Mandor, 2002) and through intelligent manipulation of objects and symbols (Ekwueme, 2007). The study tries to ascertain the impact of Hands-on-approach on the students’ academic performance and the students’ opinion about this activity-based methodology. The general objective is to assess the impact and provide another platform for students to display their understanding of what they have learnt other than the usual written tests with memorized formulae. The activity focuses on Mensuration and Geometry (with 25% questions in each area) and separation of mixtures (pure and impure substances). This paper includes the analysis of the feedback of the pre-test and post-test scores of the students before and after the Hands-on-approach was given as well as students’ interview responses. The study showed positive improvement on both the students’ performance and participation on mathematics and basic science activities and willingness on the part of the teachers to use Hands-on-approach in communicating mathematical and scientific concepts to their students.
FeCl3-catalyzed Synthesis of Dehydrodiisoeugenol
Authors: Mardhatillah Athina , Mutakin Mutakin , Levita Jutti
Published: November 2015

Dehydrodiisoeugenol (DDIE) synthesis has been performed by modifying a method recommended by Leopold with a different ratio of isoeugenol and FeCl3 (1.9:1). FeCl3 was chosen as catalyst due to its efficiency and environment-friendly property. This modification yielded 22.93 % of product. The product, a white crystalline form, was characterized using thin layer chromatography, melting point, UV, IR, HRMS, and NMR spectroscopy, as well as HPLC, employing pure DDIE as the standard. TLC chromatogram showed Rf 0.32 using n-hexane/ethyl acetate (8:2). The crystals melted at 138-139 oC, while its UV maximum was detected at l 273 nm. IR spectrum showed a specific broad O-H stretch at 3437.15 cm-1, C-H aromatic and C-H alkene at 3163.26 and 3024.38 cm-1, C-H alkyl stretch at 2951.09 and 2927.94 cm-1. An overtone peak of aromatic was detected at 2100 to 1700 cm-1. C-O peak was detected at 1126.43 cm-1. HPLC showed that this compound was eluted at 11.886 minutes after it was injected to a C18 column 250 x 4 mm using a mixture of methanol and double distilled water (73:27) for mobile phase. HRMS spectra predicted that the molecular structure is C20H22O4 as showed by abundance peak at m/z 327.1595 of [M+H]+. 1H-NMR and 13C-NMR indicated that the synthesized compound contains 13 types of proton and 20 types of carbon. Herein we reported that white needle-like crystals of DDIE using FeCl3 as catalyst had been synthesized, moreover the decreasing of the catalyst reduced the yield of the product.
Social Responsibility and Community Development in Vermont’s Food Business
Authors: Conner David S. , DeWitt Rocki-Lee , Inwood Shoshanah M. , Archer Michael
Published: November 2015

Businesses are increasingly expected to contribute to community development and sustainability. This exploratory research examines how food and agriculturally-based Vermont businesses are defining the concept of social responsibility (SR), incorporating it into their enterprises, and linking their enterprises to their communities. We develop indicators of SR and use them to examine qualitative interviews of 20 food entrepreneurs. We find that these businesses expressed commitment to and claimed actions to contribute to a broad array of SR goals, including community (with specific mention of employee well-being and improved access to healthy foods), local economy, and the environment. In many cases the respondents cited measurable impacts their actions made such as employee retention, food access, improved farm nutrient management and support for and assistance to local businesses. Contrary to prior studies, firm age did not have a measurable impact on SR values or practices. However, we found evidence of a U-shaped relationship between SR and scale, where small and large firms were more highly engaged and medium scale ones slightly less so. Implications focus on strategies for improved metrics for validation of impacts.
The Incorporation Problem in Interdisciplinary Legal Research: Some Conceptual Issues and a Practical Illustration
Authors: Roux Theunis Robert
Published: November 2015

The Incorporation Problem in Interdisciplinary Legal Research: Some Conceptual Issues and a Practical Illustration

The seriousness of the incorporation problem in interdisciplinary legal research, this article argues, depends on how legal research is understood. If legal research is understood as a single, inherently interdisciplinary discipline, the problem largely falls away. On this view, the incorporation of other disciplines into legal research is what legal academics have for the last 40 years already successfully been doing. If, on the other hand, legal research is best conceived as a multi-disciplinary field, consisting of a core discipline – doctrinal research – and various other types of mono-disciplinary and interdisciplinary research, the incorporation of other disciplines presents real difficulties. For legal academics engaged in socio-legal research, in particular, two problems arise: the practical problem of trying to address a legal professional and academic audience at the same time and the philosophical problem of trying to integrate the internal perspective of doctrinal research with the external perspective of other disciplines. In the final part of the article, these practical and philosophical difficulties are illustrated by reference to the author’s research on the politics of judicial review in new democracies.
Watch Out for the Under Toad: Role and Method of Interdisciplinary Contextualisation in Comparative Legal Research
Authors: Mak Elaine
Published: November 2015

Watch Out for the Under Toad: Role and Method of Interdisciplinary Contextualisation in Comparative Legal Research

This article studies the significance of insights from non-legal disciplines (such as political science, economics, and sociology) for comparative legal research and the methodology connected with such ‘interdisciplinary contextualisation’. Based on a theoretical analysis concerning the nature and methodology of comparative law, the article demonstrates that contextualisation of the analysis of legal rules and case law is required for a meaningful comparison between legal systems. The challenges relating to this contextualisation are illustrated on the basis of a study of the judicial use of comparative legal analysis as a source of inspiration in the judgment of difficult cases. The insights obtained from the theoretical analysis and the example are combined in a final analysis concerning the role and method of interdisciplinary contextualisation in comparative legal analysis conducted by legal scholars and legal practitioners.
A new genus for the Lesser Moorhen Gallinula angulata Sundevall, 1850 (Aves, Rallidae)
Authors: Sangster George , Garcia-R Juan Carlos , Trewick Steve A.
Published: November 2015

Molecular phylogenetic analysis has demonstrated that the genus Gallinula is not monophyletic and comprises four major lineages. A review of the nomenclature of Gallinula shows that generic names are available for three lineages but that a fourth is as yet unnamed. A new monotypic genus, Paragallinula gen. nov., is described for Lesser Moorhen (Gallinula angulata Sundevall, 1850).
Die-Hard Mubarak Supporters: A Cultural Perspective
Authors: Henry Hani M.
Published: November 2015

This study examined the persistent sympathetic response of some Egyptian citizens towards ousted president Hosni Mubarak despite his indictment for killing hundreds of peaceful demonstrators. These individuals have been occasionally characterized as victims of the so-called "Stockholm Syndrome," which was defined by mental health professionals as the tendency of victims to develop positive emotional bond towards their victimizers. However, a thematic analysis of interviews conducted with ten Mubarak supporters suggests that their sympathetic response towards the former president might be attributed to their observance of certain collectivistic values, such as filial piety and communalism. These collectivistic values might help explain why these supporters respected Mubarak as both a father and authority figure. Further, the analysis suggests that this sympathetic response was influenced by religious values and outgroup blaming. Social and political implications of this study are discussed.
Hydrothermal effect on groundwater level fluctuations: case studies of Čepkeliai and Rėkyva peatbogs, Lithuania
Authors: Kažys Justas , Rimkus Egidijus , Taminskas Julius , Butkutė Sigita
Published: November 2015

The peatbogs are very unique and relatively vulnerable ecosystems for every kind of disturbances. This research analyses the relationships between groundwater level (GWL) fluctuations and meteorological conditions in Lithuanian peatbogs. Two case study areas (Čepkeliai and Rėkyva peatbogs) with permanent GWL monitoring points were investigated. The period from 2002 till 2011 was analysed in Čepkeliai and the period from 2011 till 2014 in Rėkyva. The final results indicate that rainfall is the most important factor determining the groundwater level fluctuations in the warm season, while temperature and evapotranspiration play only a minor role. The relationship between GWL and precipitation strongly depends on soil properties. The findings in Rėkyva revealed that the reactions of GWL on meteorological conditions in various parts of the  peatbogs were not the  same. Also, the analysis showed that the reaction of GWL on precipitation differs in cold and warm seasons.
Nežymiai sutrikusio intelekto mokinių vertinimo ir įsivertinimo būdų bei metodų ypatumai geografijos pamokose
Authors: Subotkevičienė Regina
Published: November 2015

Siekdami užtikrinti ugdymo kokybę, ypač kai klasėje yra ir specialiųjų poreikių mokinių, mokytojai turi kruopščiai suplanuoti savo veiklą – parinkti tinkamus ugdymo būdus ir formas, mokymo(si) metodus ir priemones, sukurti atitinkamą ugdymo(si) aplinką. Ne mažiau svarbi kiekvieno mokytojo sėkmingos veiklos dalis – mokinių pasiekimų vertimas ir įsivertinimas. Vertinimas plačiąja prasme orientuotas į besimokančiųjų asmeninių galių plėtojimą, adekvatų savo galimybių ir gebėjimų vertinimą. Jis turi atspindėti ko mokomasi, kas išmokta, kokiais būdais ugdymo procesas vyksta, ar jis vyksta neignoruojant individualių besimokančiojo mokymosi tempų ir būdų, atsižvelgiant į besimokančiojo poreikius. Remdamasis vertinimo informacija, mokytojas suteikia pagalbą tiems mokiniams, kuriems jos reikia, pavyzdžiui, specialiųjų poreikių mokiniams. Šiame straipsnyje, pasitelkus mokslinės literatūros ir empirinių tyrimo rezultatų analizę, apžvelgiami nežymiai sutrikusio intelekto mokinių vertinimo ir įsivertinimo būdų bei metodų ypatumai geografijos pamokose.
Percepción de los estudiantes sobre el desarrollo de competencias a través de diferentes metodologías activas
Authors: Robledo Ramón Patricia , Fidalgo Redondo Raquel , Arias Gundín Olga , Álvarez Fernández Lourdes
Published: November 2015

El objetivo del estudio es analizar comparativamente la percepción del alumnado sobre la influencia diferencial que cinco métodos de enseñanza aprendizaje activos (aprendizaje basado en problemas; estudio de casos; estudio compartido; estudio dirigido y  método de expertos) tienen en el desarrollo de competencias instrumentales; sistémicas y personales. Participaron 280 estudiantes de Educación de la Universidad de León; quienes recibieron sus temarios siguiendo las metodologías activas analizadas. Tras la aplicación de cada metodología se administró el Cuestionario de evaluación de competencias generales que evalúa el grado en que el alumnado cree haber desarrollado las competencias. Los resultados señalan que el aprendizaje basado en problemas favorece un mayor desarrollo de competencias que el resto de metodologías. El estudio compartido es el método con menor capacidad para estimular el desarrollo de competencias metodológicas; lingüísticas; de trabajo en equipo; compromiso ético y liderazgo. Se analizan y discuten los resultados; sus implicaciones y limitaciones.