bluuebunny/crossref_metadata_2025 huggingface dataset:
3-D Biped Robot Walking along Slope with Dual Length Linear Inverted Pendulum Method (DLLIPM)
Authors: Ali Fariz , Shukor Ahmad Zaki Hj. , Miskon Muhammad Fahmi , Nor Mohd Khairi Mohamed , Salim Sani Irwan Md
Published: November 2013

A new design method to obtain walking parameters for a three-dimensional (3D) biped walking along a slope is proposed in this paper. Most research is focused on the walking directions when climbing up or down a slope only. This paper investigates a strategy to realize biped walking along a slope. In conventional methods, the centre of mass (CoM) is moved up or down during walking in this situation. This is because the height of the pendulum is kept at the same length on the left and right legs. Thus, extra effort is required in order to bring the CoM up to higher ground. In the proposed method, a different height of pendulum is applied on the left and right legs, which is called a dual length linear inverted pendulum method (DLLIPM). When a different height of pendulum is applied, it is quite difficult to obtain symmetrical and smooth pendulum motions. Furthermore, synchronization between sagittal and lateral planes is not confirmed. Therefore, DLLIPM with a Newton Raphson algorithm is proposed to solve these problems. The walking pattern for both planes is designed systematically and synchronization between them is ensured. As a result, the maximum force fluctuation is reduced with the proposed method.
Mechanical Performance of a Cascaded V-Shaped Electrothermal Actuator
Authors: Shen Xuejin , Chen Xiangyu
Published: November 2013

The function and performance of MEMS are affected by the output ability of the displacement and force of microactuators. The lateral deflection of cascaded V-shaped electrothermal actuators is modelled as a triple, statically indeterminate problem. An iteration algorithm is set up to calculate the output displacement and typical forces in anchors. The calculated results of this model agree well with our own simulation results as well as with the experimental and calculated results in the literature, and we conclude that the model is credible. The paper also discusses the effects of the structure parameters and temperature increments on the displacement production ability. Clear differences were found between single and cascaded V-shaped electrothermal actuators. For the former, the maximum deflection takes place in a 0.04 rad beam angle, while for the latter the beam angle is 0.19 rad. For both types of actuators, the deflection is unrelated to the beam thickness. The displacement of the cascaded V-shaped electrothermal actuator is proportional to the temperature increment and beam length, but is inversely proportional to the beam width. Experiments on the output ability of cascaded V-shaped electrothermal actuators validated the calculated and simulation results.
Singularity Representation and Workspace Determination of a Special Class of the Gough-Stewart Platforms
Authors: Li Baokun , Cao Yi , Zhang Qiuju , Wang Chuanli
Published: November 2013

The closed-loop nature of the Gough-Stewart platform generates complex singular configurations inside the workspace and makes its workspace smaller compared to the serial mechanism. It is desirable to obtain a non-singular workspace based on describing the constraint workspace and representing the singularities inside the constraint workspace. Some algorithms have been proposed by researchers to find the workspace boundary, but cannot locate the voids inside the workspace and are not applicable to the generation of a workspace with more than one zone. In this paper, the position-singularity expression in ℜ3 and the orientation-singularity expression in SO (3) are obtained, respectively. The new algorithms of the two types of constraint workspace in ℜ3 and in SO (3) are developed considering the limitations of the kinematic pairs. It can be shown that the singularities may exist inside the constraint workspace. Based on the singularity representation and the abovementioned constraint workspace determination, the two types of procedures of the non-singular workspace in ℜ3 and in SO (3) are further addressed, respectively. When the moving platform translates inside the non-singular position-workspace in ℜ3 for a constant-orientation or rotates inside the non-singular orientation-workspace in SO (3) for a given position, the mechanism is not singular. The two types of non-singular workspace representations in ℜ3 and SO (3) can help the designers to explore the singularity-free path planning, on which our next work will be focused. The novel method of workspace determination of the mechanism can also be used for the workspace analysis of the other types of parallel mechanisms.
Proposta de pré-qualificação pozolânica de materiais geológicos: difratometria de raios X como método alternativo
Authors: Montanheiro Tarcísio José , Yamamoto Jorge Kazuo , Kihara Yushiro
Published: November 2013

Este trabalho apresenta um método alternativo para estimar o potencial pozolânico de materiais geológicos, baseado na análise de difração de raios X de argamassas obtidas a partir de uma mistura de duas partes de cal (hidróxido de cálcio) e uma parte de material moído e água. A mistura é colocada para secar em estufa a 30ºC durante 7 dias, quando é avaliada a capacidade de reação e fixação de cal pela determinação da resistência à compressão. A argamassa é moída e submetida à difração de raios X, que revela os compósitos neoformados como produtos da reação pozolânica. Os componentes mais importantes estão associados ao silicato de cálcio hidratado (C-S-H) e suas formas derivadas com alumínio, ferro, sódio e potássio. A presença desses novos compostos indica que o material geológico pode apresentar uma reação pozolânica favorável e, portanto, constituir uma pozolana natural.
Coberturas cenozóicas e estruturas deformadoras na Depressão Periférica Paulista, Campinas, São Paulo
Authors: Fernandes Amélia João , Mello Claudio Limeira
Published: November 2013

Este trabalho teve como objetivo mapear e estabelecer a estratigrafia dos depósitos cenozóicos e caracterizar as estruturas tectônicas deformadoras em um setor da Região Metropolitana de Campinas, no contato da Depressão Periférica Paulista com o Planalto Atlântico. Na região de estudo foram identificadas três unidades cenozóicas, associadas a depósitos de topo e encosta de colinas, que correspondem, da mais antiga à mais jovem, à Formação Rio Claro (Trc) e às coberturas de superfícies aplainadas (TQsp) e de fluxos gravitacionais (Qfg). A Trc é constituída por fácies de ambiente fluvial meandrante intercaladas, ou em contato lateral, com fácies de fluxos gravitacionais. A TQsp ocorre nos topos de colinas e morrotes e nas ombreiras planas de caimento suave; é constituída por material areno-argiloso a arenoso, com linha de seixos na base. A Qfg é de ocorrência restrita e associa-se a encostas de vales atuais, espessando-se em direção à sua base; são depósitos coluviais, ocasionalmente intercalados com depósitos de terraços fluviais. Os depósitos Qfg apresentam linha de seixos basal composta por clastos ferruginizados, que se originaram das couraças ferruginosas desenvolvidas sobre os depósitos da Trc. Na área foram identificadas estruturas de três eventos tectônicos cenozóicos. O mais antigo é de regime transcorrente com σ1 de orientação aproximadamente EW, provavelmente contemporâneo à deposição da Trc; originou falhas transcorrentes de direção NE e NW e falhas normais de direção ao redor de EW. O evento seguinte, com σ1 de direção NW, produziu falhas EW a WNW e NS a NNW transcorrentes, com componente normal. Este evento afeta a Trc e a TQsp e produziu desnivelamentos tectônicos da superfície basal da Trc que, somados, chegam a pelo menos 50m. O evento mais jovem é de regime extensional, com σ3 de direção NE, e gerou falhas normais que cortam a Trc e a TQsp.
Snapshot of Statistical Methods Used in Geriatric Cohort Studies: How Do We Treat Missing Data in Publications?
Authors: Geva Diklah , Shahar Danit , Harris Tamara , Tepper Sigal , Friger Michael
Published: November 2013

Background: Geriatric studies often miss data of frail participants. The aim of this paper is to explore which missing data methodologies have entered current practice and to discuss the potential impact of ignoring the issue.
Methods: A Sample of 103 articles was drawn from key cohort studies: Health ABC, InCHIANTI, LASA, BLSA, EPESE, and KLoSHA. The studies were classified according to missing data methodologies used.
Results: Seventy-seven percent described the selected analysis data set and only 28% used a method of handling all available observations per case. Missing data dedicated methods were rare (< 10%), applying single or multiple imputations for baseline variables. Studies with longer follow-up periods more often employed longitudinal analysis methodologies.
Conclusions: Despite the recognition that missing data is a major problem in studies of older persons, few published studies account for missing data using limited methodologies; this could affect the validity of study conclusions. We propose researchers apply Joint Modeling of longitudinal and time-to-event data, using shared-parameter model.
CO2 directly modulates connexin 26 by formation of carbamate bridges between subunits
Authors: Meigh Louise , Greenhalgh Sophie A , Rodgers Thomas L , Cann Martin J , Roper David I , Dale Nicholas
Published: November 2013

Homeostatic regulation of the partial pressure of CO2 (PCO2) is vital for life. Sensing of pH has been proposed as a sufficient proxy for determination of PCO2 and direct CO2-sensing largely discounted. Here we show that connexin 26 (Cx26) hemichannels, causally linked to respiratory chemosensitivity, are directly modulated by CO2. A ‘carbamylation motif’, present in CO2-sensitive connexins (Cx26, Cx30, Cx32) but absent from a CO2-insensitive connexin (Cx31), comprises Lys125 and four further amino acids that orient Lys125 towards Arg104 of the adjacent subunit of the connexin hexamer. Introducing the carbamylation motif into Cx31 created a mutant hemichannel (mCx31) that was opened by increases in PCO2. Mutation of the carbamylation motif in Cx26 and mCx31 destroyed CO2 sensitivity. Course-grained computational modelling of Cx26 demonstrated that the proposed carbamate bridge between Lys125 and Arg104 biases the hemichannel to the open state. Carbamylation of Cx26 introduces a new transduction principle for physiological sensing of CO2.
Natural Hazards Experts Learn First Hand from the Colorado Storm and Flood
Authors: Showstack Randy
Published: November 2013

The mid‐September deluge of parts of central Colorado—which broke many precipitation records and devastated communities—also personally affected a number of natural hazards experts who live there.
Eberhard Fahrbach (1948–2013)
Authors: Hellmer Hartmut , Schauer Ursula , Pfeiffer Eva‐Maria , Rintoul Steve
Published: November 2013

Eberhard Fahrbach, an internationally known oceanographer, died on 21 April 2013 at age 65 after battling a brain tumor. He had retired 1 year earlier from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research in Bremerhaven, Germany, where he directed research on observational oceanography.
Epic Fail: What a Perfectly Putrid Poster Can Do for You
Authors: Cooper Paul , Galkiewicz Julia
Published: November 2013

After months, perhaps years, of fieldwork, lab work, and analysis, you have results that you simply have to share with the world. You've shelled out for your Fall Meeting registration. You're stoked that your poster session doesn't coincide with any of the talks you've marked as essential. And because your BFF has agreed to share accommodation costs, you have a suite at the Hotel Nikko. No one can deny that you're as confident as a Kardashian and as primed for launch as a fully fuelled Titan rocket. Ain't no stoppin' you now!
Exploring Planetary Atmospheres
Authors: Simon‐Miller Amy A. , Del Genio Anthony D.
Published: November 2013

The past decade has been an exciting time to study atmospheres. Fundamental studies of Earth's general circulation and hydrological cycle have been stimulated by questions about past climates and the future impacts of humankind's activities. Long‐term spacecraft and Earth‐based observations of solar system planets have reinvigorated the study of comparative planetary climatology. The explosion in discoveries of planets outside our solar system has made atmospheric science integral to understanding the diversity of our solar system and the potential habitability of planets outside it. Thus, the AGU Chapman Conference: Crossing the Boundaries in Planetary Atmospheres—From Earth to Exoplanets, gathered Earth, solar system, and exoplanet scientists to share experiences, insights, and challenges from their individual disciplines and to discuss areas in which thinking broadly might enhance scientists' fundamental understanding of how atmospheres work.
Multidisciplinary Studies of the Global Carbon Cycle
Authors: Zeng Ning , Heimann Martin , Canadell Josep
Published: November 2013

For several days in May 2013, the atmospheric carbon dioxide (CO2) mole fraction measured at Mauna Loa, Hawaii, exceeded a landmark value of 400 parts per million. Two weeks later, the 9th International Carbon Dioxide Conference (ICDC9; http://icdc9.org) took place in Beijing. Started by Charles D. Keeling and Hans Oeschger in 1981 and held once every 4 years, the ICDC series has helped to transform carbon cycle research into a multidisciplinary field that encompasses major areas in Earth and environmental sciences, as well as energy and other socioeconomic domains, as evident in the composition of the more than 500 attendees of the meeting.
Process Review Under Way for AGU Fellows Program
Authors: Fine Rana , Williams Billy
Published: November 2013

A new task force has been appointed and work is now under way to review and suggest improvements for the AGU Union Fellows Program. The work plan will review both the process and practices for the AGU Fellows program with over‐arching goals of assuring fairness and transparency while retaining program prestige. Selection as a Fellow is one of AGU's highest honors.
Eisenman Receives 2012 Cryosphere Young Investigator Award: Citation
Authors: Schneider Tapio , Tziperman Eli , Wettlaufer John S.
Published: November 2013

One can appreciate that sea ice is a barometer and important feedback for climate change when one considers the ice–albedo feedback in a comparative sense. Whereas the Greenland ice sheet is 3 kilometers thick, sea ice is 3 meters thick, underlain by an ocean deeper than the Greenland ice sheet is thick. During a season, the areal change of Arctic sea ice cover is roughly 4 times larger than the area of Greenland. These huge annual oscillations in the ice cover have occurred for longer than humanity has been able to ponder them. This is just one of the many aspects that capture our attention in considering the scientific problem of sea ice and climate, which is a principal area of interest for Ian Eisenman.
Deep‐sea foraminifera shell isotopes unaffected by recrystallization
Authors: Schultz Colin
Published: November 2013

Measuring isotopes preserved in the shells of ancient single‐celled foraminifera—specifically, tracking two sets of isotope ratios, carbon‐13 to carbon‐12 and oxygen‐18 to oxygen‐16—is a key way that paleoceanographers reconstruct the temperature of the ancient ocean and past global carbon cycling. Foraminifera build their shells from the carbon and oxygen in the seawater, and the relative uptakes of these isotopes change with temperature.
“Sediment capacitors” help explain debris flow events
Authors: Balcerak Ernie
Published: November 2013

Runoff during rainstorms plays a key role in initiating many debris flow events, but exactly how these debris flow events begin is not well understood. To better understand how debris flows are initiated by runoff, Kean et al. monitored both the triggering rainfall and the associated debris flow at two small catchments: a bedrock‐dominated alpine basin in central Colorado and a recently burned area in southern California. They also studied video footage from cameras at the Colorado site.
Are scale‐invariant stress orientations related to seismicity rates near the San Andreas fault?
Authors: Davidsen Jörn , Schumann Aicko Y. , Naylor Mark
Published: November 2013

Based on an analysis of the direction of maximum horizontal compressive stress as a function of depth as observed at different scientific wells along the San Andreas fault, it has recently been suggested that the scale‐invariant fluctuations in the stress orientation over intervals from tens of centimeters to several kilometers are directly related to the local earthquake magnitude‐frequency statistics. Here we mathematically analyze the possibility of such a relationship and show that the magnitude‐frequency statistics alone is insufficient to explain the scaling of the stress orientation fluctuations. While stress perturbations caused by slip on adjacent faults of various sizes can still be responsible for these fluctuations, the average amplitude of the induced changes in the orientation would have to increase nonlinearly with the fault size. As the example of two research wells near the San Andreas fault also shows, the specific nonlinear form would have to depend sensitively on the specific geographic location. We conclude that the observed scale‐invariant fluctuations in the stress orientation are more likely a consequence of a combination of local seismicity rates and the specific local fault structure.
Spontaneous formation of nonspherical water ice grains in a plasma environment
Authors: Chai Kil‐Byoung , Bellan Paul M.
Published: November 2013

Saturn's rings, terrestrial polar mesospheric clouds, and astrophysical molecular clouds are all dusty plasma environments where tiny grains of water ice are an important constituent. Existing models typically assume that the ice grains are spherical and then invoke various arguments about the normal distribution or the power law dependence of grain number density on grain radius. Using a laboratory plasma in which water ice grains spontaneously form, we investigated the validity of the traditional assumption that these grains are spherical. We found that in certain cases at low ambient pressures, water ice grains in the laboratory dusty plasma are not spherical but instead are highly elongated, i.e., ellipsoidal. Preliminary analysis suggests that electrical forces associated with the dusty plasma environment are responsible for the nonspherical shape.
An observational and theoretical study of the longitudinal variation in neutral temperature induced by aurora heating in the lower thermosphere
Authors: Xu Jiyao , Smith A. K. , Wang Wenbin , Jiang Guoying , Yuan Wei , Gao Hong , Yue Jia , Funke B. , López‐Puertas M. , Russell James M.
Published: November 2013

In this paper, observations by thermosphere, ionosphere, mesosphere energetics and dynamics/Sounding of the Atmosphere using Broadband Emission Radiometry from 2002 to 2012 and by Envisat/Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) from 2008 to 2009 are used to study the longitudinal structure of temperature in the lower thermosphere. In order to remove the longitudinal structure induced by tides, diurnally averaged SABER temperatures are used. For MIPAS data, we use averaged temperatures between day and night. The satellite observations show that there are strong longitudinal variations in temperature in the high‐latitude lower thermosphere that persist over all seasons. The peak of the diurnally averaged temperature in the lower thermosphere always occurs around the auroral zone. A clear asymmetry between the two hemispheres in the longitudinal temperature structure is observed, being more pronounced in the Southern than in the Northern Hemisphere. In both hemispheres, the longitudinal variation is dominated by the first harmonic in longitude. The total radiative cooling observed by SABER has a structure in longitude that is similar to that of temperature. Modeling simulations using the Thermosphere‐Ionosphere‐Electrodynamics General Circulation Model reproduce similar features of the longitudinal variations of temperature in the lower thermosphere. Comparison of two model runs with and without auroral heating confirms that auroral heating causes the observed longitudinal variations. The multiyear averaged vertical structures of temperature observed by the two satellite instruments indicate that the impact of auroral heating on the thermodynamics of the neutral atmosphere can penetrate down to about 105 km.
A noise‐aware combination of dual‐frequency measurements from GPS radio occultation
Authors: Wee Tae‐Kwon , Kuo Ying‐Hwa
Published: November 2013

One of the fundamental difficulties that arise when using GPS Radio Occultation (RO) data in exploiting the stratosphere is that the air becomes rarefied with increasing height and accentuates the ionospheric effect and noise contained in the measurement. Customarily, the conventional linear combination (CLC) is used to extract neutral atmospheric components from dual‐frequency (L1 and L2) RO data. The CLC combines and magnifies measurement noises, and thus works well only for those measurements of low noise. Although the L1 data are of considerably higher quality than the L2 data, the CLC does not take this into account and treats both equally; this makes the CLC‐produced data less attractive. The authors propose a new approach, named Noise‐Aware Combination (NAC), which is a generalized combination that factors in the presence of measurement noise. In this NAC method, the L1 and L2 data are each regarded independently, with each contributing to the combination according to its dynamically assessed accuracy. The performance of both the CLC and NAC are tested with two sets of data: one of synthetic data and the other of real data. The tests confirm that the NAC yields significant error reductions when compared to the CLC. While the noise in the CLC‐produced data stands out in high altitudes and compels the data to be blended with the a priori, the NAC relies far less on this blending. The clear advantage of the NAC over the CLC would greatly enhance the value of RO for climate research.
Direct estimation of land surface albedo from VIIRS data: Algorithm improvement and preliminary validation
Authors: Wang Dongdong , Liang Shunlin , He Tao , Yu Yunyue
Published: November 2013

Land surface albedo (LSA), part of the Visible Infrared Imaging Radiometer Suite (VIIRS) surface albedo environmental data record (EDR), is an essential variable regulating shortwave energy exchange between the land surface and the atmosphere. Two sub‐algorithms, the dark pixel sub‐algorithm (DPSA) and the bright pixel sub‐algorithm (BPSA), were proposed for retrieving LSA from VIIRS data. The BPSA estimates LSA directly from VIIRS top‐of‐atmosphere (TOA) reflectance through simulation of atmospheric radiative transfer. Several changes have been made to improve the BPSA since the deployment of VIIRS. A database of the Moderate Resolution Imaging Spectroradiometer (MODIS) bidirectional reflectance distribution function (BRDF) is collected and converted to bidirectional reflectance at VIIRS bands. The converted reflectance is then used as input to the atmospheric radiative transfer model to generate a look‐up table (LUT) of regression coefficients with consideration of surface BRDF. Before its implementation in the operational system, the new BPSA is tested on the local infrastructure. The incorporation of the surface BRDF improves the accuracy of LSA estimation and reduces the temporal variation of LSA over stable surfaces. VIIRS LSA retrievals agree well with the MODIS albedo products. Comparison with field measurements at seven Surface Radiation (SURFRAD) Network sites shows that VIIRS LSA retrieved from the LUT with surface BRDF has an R2 value of 0.80 and root mean square error of 0.049, better than MODIS albedo products. The VIIRS results have a slight negative bias of 0.004, whereas the MODIS albedo is underestimated with a larger negative bias of 0.026.
Hydrodynamic and suspended sediment transport controls on river mouth morphology
Authors: Falcini F. , Piliouras A. , Garra R. , Guerin A. , Jerolmack D. J. , Rowland J. , Paola C.
Published: November 2013

River mouths building into standing bodies of water have strikingly varied growth habits. This presents a compelling pattern formation problem that is also of great practical relevance for subsurface prediction and managing coastal wetlands. Here we present a generalized 2.5‐dimensional potential vorticity (PV) theory that explains sedimentation patterns of a sediment‐laden stationary jet by coupling an understanding of vorticity with suspended sediment concentration fields. We explore the physical meaning of this new sediment‐PV definition, and its impact on outflow depositional patterns, by analyzing data from a shallow wall‐bounded plane jet experiment and by discussing new theoretical insights. A key result is that lateral advection and diffusion of suspended sediment are directly proportional to jet vorticity, a feature that reveals the mechanistic process that forms elongated channels by focused levee deposition. The new PV theory constitutes a more generalized mathematical framework that expands the Rouse theory for the equilibrium of suspended sediment.
Dynamics of hydrogen peroxide in a coral reef: Sources and sinks
Authors: Shaked Yeala , Armoza‐Zvuloni Rachel
Published: November 2013

The dynamics of hydrogen peroxide (H2O2) was studied in the fringing coral reef off the coast of Eilat, Red Sea. Diurnal changes in H2O2 concentrations in the reef lagoon were typical of photochemically produced species. During the daytime H2O2 accumulated in the lagoon at low tide and exceeded open water concentrations by 100–250 nM. Elevated H2O2 decay kinetics (termed hereafter antioxidant activity) were also recorded in the lagoon at low tide. The observed antioxidant activities were high enough to moderate H2O2 accumulation in the lagoon. In pursuit of the antioxidant source, the ability of corals to release antioxidant activity to their surrounding water was examined in both natural and laboratory settings. Water collected in situ from surfaces of individual corals and next to a coral knoll contained high antioxidant activity. Incubation experiments revealed that many Red Sea corals release antioxidant activity to their external milieu. Besides serving a potential antioxidant source to the reef system, the antioxidant activity detected on coral surfaces enabled corals to lower H2O2 concentrations in their vicinity. The ability of corals to offset exogenous H2O2 was validated in incubations with Stylophora pistillata in the absence of mixing. Conversely, corals subjected to mixing in a beaker were found to release H2O2, implying that corals may act as both a sink and a source for H2O2 in the reef. This newly described ability of corals to change H2O2 dynamics by releasing both H2O2 and antioxidants may bare important implications for coral physiology and interactions with the environment.
Multiobjective design of interplant trigeneration systems
Authors: Hipólito‐Valencia Brígido Jesús , Lira‐Barragán Luis Fernando , Ponce‐Ortega José María , Serna‐González Medardo , El‐Halwagi Mahmoud M.
Published: November 2013

A systematic approach for heat integration into an eco‐industrial park through an integrated trigeneration system is presented. The approach is based on a new superstructure formulated as a multiobjective mixed‐integer nonlinear programming model, where intraplant and interplant heat exchange for the process streams is allowed, in addition to the energy integration into the utility system that is constituted by a steam Rankine cycle (to produce electric power and hot utility), an organic Rankine cycle (to recover waste heat and produce electric power), and an absorption refrigeration cycle (to recover waste heat and provide refrigeration). To run the utility system, several external heat sources (solar, fossil fuels, and biofuels) are considered, which impact the economic, environmental, and social objectives considered in the model. A systematic approach to tradeoff the objectives considered is presented. Two examples are presented, where the advantages of the integrated eco‐industrial park are shown. © 2013 American Institute of Chemical Engineers AIChE J, 60: 213–236, 2014
Algal biomass conversion to bioethanol – a step‐by‐step assessment
Authors: Harun Razif , Yip Jason W. S. , Thiruvenkadam Selvakumar , Ghani Wan A. W. A. K. , Cherrington Tamara , Danquah Michael K.
Published: November 2013

The continuous growth in global population and the ongoing development of countries such as China and India have contributed to a rapid increase in worldwide energy demand. Fossil fuels such as oil and gas are finite resources, and their current rate of consumption cannot be sustained. This, coupled with fossil fuels' role as pollutants and their contribution to global warming, has led to increased interest in alternative sources of energy production. Bioethanol, presently produced from energy crops, is one such promising alternative future energy source and much research is underway in optimizing its production. The economic and temporal constraints that crop feedstocks pose are the main downfalls in terms of the commercial viability of bioethanol production. As an alternative to crop feedstocks, significant research efforts have been put into utilizing algal biomass as a feedstock for bioethanol production. Whilst the overall process can vary, the conversion of biomass to bioethanol usually contains the following steps: (i) pretreatment of feedstock; (ii) hydrolysis; and (iii) fermentation of bioethanol. This paper reviews different technologies utilized in the pretreatment and fermentation steps, and critically assesses their applicability to bioethanol production from algal biomass. Two different established fermentation routes, single‐stage fermentation and two‐stage gasification/fermentation processes, are discussed. The viability of algal biomass as an alternative feedstock has been assessed adequately, and further research optimisation must be guided toward the development of cost‐effective scalable methods to produce high bioethanol yield under optimum economy.
Increased expression of the receptor for advanced glycation end‐products in human peripheral neuropathies
Authors: Juranek Judyta K. , Kothary Pratik , Mehra Alka , Hays Arthur , Brannagan Thomas H. , Schmidt Ann Marie
Published: November 2013

Background

Diabetic neuropathy and idiopathic neuropathy are among the most prevalent neuropathies in human patients. The molecular mechanism underlying pathological changes observed in the affected nerve remains unclear but one candidate molecule, the receptor for advanced glycation end‐products (RAGE), has recently gained attention as a potential contributor to neuropathy. Our previous studies revealed that RAGE expression is higher in porcine and murine diabetic nerve, contributing to the inflammatory mechanisms leading to diabetic neuropathy. Here, for the first time, we focused on the expression of RAGE in human peripheral nerve.

Methods

Our study utilized de‐identified human sural nerve surplus obtained from 5 non‐neuropathic patients (control group), 6 patients with long‐term mild‐to‐moderate diabetic neuropathy (diabetic group) and 5 patients with mild‐to‐moderate peripheral neuropathy of unknown etiology (idiopathic group). By using immunofluorescent staining and protein immunoblotting we studied the expression and colocalization patterns of RAGE and its ligands: carboxymethyllysine (CML), high mobility group box 1 (HMBG1) and mammalian Diaphanous 1 (mDia1) in control and neuropathic nerves.

Results

We found that in a normal, healthy human nerve, RAGE is expressed in almost 30% of all nerve fibers and that number is higher in pathological states such as peripheral neuropathy. We established that the levels of RAGE and its pro‐inflammatory ligands, CML and HMBG1, are higher in both idiopathic and diabetic nerve, while the expression of the RAGE cytoplasmic domain‐binding partner, mDia1 is similar among control, diabetic, and idiopathic nerve. The highest number of double stained nerve fibers was noted for RAGE and CML: ~76% (control), ~91% (idiopathic) and ~82% (diabetic) respectively.

Conclusions

Our data suggest roles for RAGE and its inflammatory ligands in human peripheral neuropathies and lay the foundation for further, more detailed and clinically oriented investigation involving these proteins and their roles in disorders of the human peripheral nerve.
Two intrauterine rescue transfusions in treatment of severe fetomaternal hemorrhage in the early third trimester
Authors: Stefanovic Vedran , Paavonen Jorma , Halmesmäki Erja , Luukkainen Päivi , Tikkanen Minna , Nuutila Mika , Poikkeus Piia
Published: November 2013

Key Clinical Message

When massive fetomaternal hemorrhage is diagnosed in the early third trimester of pregnancy, serial fetal intravascular transfusion may be an alternative to immediate delivery.
Cyclometalated Iridium(III) Complexes with Deoxyribose Substituents
Authors: Maity Ayan , Choi Jung‐Suk , Teets Thomas S. , Deligonul Nihal , Berdis Anthony J. , Gray Thomas G.
Published: November 2013

Fundamental study of enzymatic nucleoside transport suffers for lack of optical probes that can be tracked noninvasively. Nucleoside transporters are integral membrane glycoproteins that mediate the salvage of nucleosides and their passage across cell membranes. The substrate recognition site is the deoxyribose sugar, often with little distinction among nucleobases. Reported here are nucleoside analogues in which emissive, cyclometalated iridium(III) complexes are “clicked” to C‐1 of deoxyribose in place of canonical nucleobases. The resulting complexes show visible luminescence at room temperature and 77 K with microsecond‐length triplet lifetimes. A representative complex is crystallographically characterized. Transport and luminescence are demonstrated in cultured human carcinoma (KB3‐1) cells.
Reducing time‐to‐treatment in underserved Latinas with breast cancer: The Six Cities Study
Authors: Ramirez Amelie , Perez‐Stable Eliseo , Penedo Frank , Talavera Gregory , Carrillo J. Emilio , Fernández María , Holden Alan , Munoz Edgar , San Miguel Sandra , Gallion Kipling
Published: November 2013

BACKGROUND

The interaction of clinical and patient‐level challenges following a breast cancer diagnosis can be a significant source of health care disparities. Failure to address specific cultural features that create or exacerbate barriers can lead to less‐than optimal navigation results, specifically in Hispanic/Latino women.

METHODS

To address these disparities, the study leaders in San Antonio, Texas, and 5 other regional partners of the federally‐funded Redes En Acción: The National Latino Cancer Research Network developed a culturally‐tailored patient navigation intervention model for Latinas with breast cancer.

RESULTS

Compared with control patients, a higher percentage of navigated subjects initiated treatment within 30 days (69.0% versus 46.3%, P = .029) and 60 days (97.6% versus 73.1%, P = .001) following their cancer diagnosis. Time from cancer diagnosis to first treatment was lower in the navigated group (mean, 22.22 days; median, 23.00 days) than controls (mean, 48.30 days; median, 33.00 days). These results were independent of cancer stage at diagnosis and numerous characteristics of cancer clinics and individual participants.

CONCLUSIONS

Successful application of patient navigation increased the percentage of Latinas initiating breast cancer treatment within 30 and 60 days of diagnosis. This was achieved through navigator provision of services such as accompaniment to appointments, transportation arrangements, patient telephone support, patient‐family telephone support, Spanish‐English language translation, and assistance with insurance paperwork. Cancer 2014;120:752–760. © 2013 American Cancer Society.
Phase 2 trial of aromatase inhibition with letrozole in patients with uterine leiomyosarcomas expressing estrogen and/or progesterone receptors
Authors: George Suzanne , Feng Yang , Manola Judith , Nucci Marisa R. , Butrynski James E. , Morgan Jeffrey A. , Ramaiya Nikhil , Quek Richard , Penson Richard T. , Wagner Andrew J. , Harmon David , Demetri George D. , Krasner Carolyn
Published: November 2013

BACKGROUND

Advanced uterine leiomyosarcoma (ULMS) is an incurable disease. A significant percentage of cases of ULMS express estrogen and/or progesterone receptors (ER and/or PR). To the authors' knowledge, the role of estrogen suppression in disease management is not known.

METHODS

The authors performed a single‐arm phase 2 study of the aromatase inhibitor letrozole at a dose of 2.5 mg daily in patients with unresectable ULMS with ER and/or PR expression confirmed by immunohistochemistry. Tumor assessments were performed at baseline, 6 weeks, 12 weeks, and every 8 weeks thereafter. Toxicity was monitored throughout treatment. The primary endpoint was the progression‐free survival at 12 weeks.

RESULTS

A total of 27 patients was accrued, with a median of 2 prior treatment regimens (range, 0‐9 treatment regimens). The median duration of protocol treatment was 2.2 months (range, 0.4 months‐9.9 months). The 12‐week progression‐free survival rate was 50% (90% confidence interval, 30%‐67%). The best response was stable disease in 14 patients (54%; 90% CI, 36%‐71%). Three patients, all of whom had tumors expressing ER and PR in > 90% of tumor cells, continued to receive letrozole for > 24 weeks. The most common reason for treatment discontinuation was disease progression (85%). Letrozole was found to be well tolerated.

CONCLUSIONS

Letrozole met protocol‐defined criteria as an agent with activity in patients with advanced ULMS. Patients with the longest progression‐free survival rate were those whose tumors strongly and diffusely expressed ER and PR. Cancer 2014;120:738–743. © 2013 American Cancer Society.
Dedifferentiated liposarcoma and pleomorphic liposarcoma
Authors: Mariño‐Enríquez Adrián , Hornick Jason L. , Dal Cin Paola , Cibas Edmund S. , Qian Xiaohua
Published: November 2013

BACKGROUND

Dedifferentiated liposarcoma (DDLPS) and pleomorphic liposarcoma (PLPS) are distinct high‐grade liposarcomas. DDLPS is a nonlipogenic sarcoma characterized by amplification of MDM2 and CDK4. PLPS is a high‐grade sarcoma containing lipoblasts, characterized by a complex karyotype and a more aggressive clinical course. Rarely, DDLPS shows lipogenic differentiation, mimicking PLPS. The cytomorphologic features of DDLPS and PLPS and the utility of ancillary studies have not been systemically analyzed.

METHODS

Cytologic preparations of 25 DDLPS and 13 PLPS, all histologically confirmed, were retrospectively reviewed along with clinical and cytogenetic data. Sample cellularity, vascular architecture, background material, predominant cell morphology, quality of the cytoplasm, and nuclear pleomorphism were compared for both tumor types. Immunohistochemistry for MDM2 and CDK4 was performed on cell blocks and/or core needle biopsies.

RESULTS

Fine‐needle aspirate smears from both DDLPS and PLPS were variably cellular, composed of cellular clusters and noncohesive cells. Abundant myxoid stroma was present in ∼25% of DDLPS and PLPS cases, whereas branching curvilinear vessels were more common in DDLPS than in PLPS (7 of 25 versus 2 of 13). Tumors were composed of predominantly spindled (18 of 25 DDLPS versus 3 of 13 PLPS) or epithelioid cells (7 of 25 DDLPS versus 6 of 13 PLPS). Pleomorphic cells were predominant in 3 PLPS, and were frequent in both (13 of 25 DDLPS versus 10 of 13 PLPS). The cytoplasm was mostly fibrillary and often vacuolated in both entities. Other features included necrosis, mitoses, and a prominent inflammatory infiltrate. The main cytologic differences were the presence of marked pleomorphism, abundant lipoblasts, and cells with microvacuolated cytoplasm in most PLPS. A total of 24 (96%) and 20 (80%) cases of DDLPS expressed MDM2 and CDK4, respectively, whereas none of the PLPS expressed both markers. Six DDLPS tested showed ring or giant marker chromosomes and/or MDM2 amplification by fluorescence in situ hybridization; 2 PLPS had complex karyotypes.

CONCLUSIONS

DDLPS and PLPS exhibit variable and occasionally overlapping cytologic features. The presence of lipoblasts, cells with microvacuolated cytoplasm, and marked pleomorphism are more suggestive of PLPS, but these characteristics can be present in DDLPS. Coexpression of MDM2 and CDK4 distinguishes DDLPS from PLPS. Cancer (Cancer Cytopathol) 2014;122:128–37. © 2013 American Cancer Society.
AMP‐activated protein kinase mediates activity‐dependent axon branching by recruiting mitochondria to axon
Authors: Tao Kentaro , Matsuki Norio , Koyama Ryuta
Published: November 2013

During development, axons are guided to their target areas and provide local branching. Spatiotemporal regulation of axon branching is crucial for the establishment of functional connections between appropriate pre‐ and postsynaptic neurons. Common understanding has been that neuronal activity contributes to the proper axon branching; however, intracellular mechanisms that underlie activity‐dependent axon branching remain elusive. Here, we show, using primary cultures of the dentate granule cells, that neuronal depolarization‐induced rebalance of mitochondrial motility between anterograde versus retrograde transport underlies the proper formation of axonal branches. We found that the depolarization‐induced branch formation was blocked by the uncoupler p‐trifluoromethoxyphenylhydrazone, which suggests that mitochondria‐derived ATP mediates the observed phenomena. Real‐time analysis of mitochondrial movement defined the molecular mechanisms by showing that the pharmacological activation of AMP‐activated protein kinase (AMPK) after depolarization increased anterograde transport of mitochondria into axons. Simultaneous imaging of axonal morphology and mitochondrial distribution revealed that mitochondrial localization preceded the emergence of axonal branches. Moreover, the higher probability of mitochondrial localization was correlated with the longer lifetime of axon branches. We qualitatively confirmed that neuronal ATP levels decreased immediately after depolarization and found that the phosphorylated form of AMPK was increased. Thus, this study identifies a novel role for AMPK in the transport of axonal mitochondria that underlie the neuronal activity‐dependent formation of axon branches. © 2013 Wiley Periodicals, Inc. Develop Neurobiol 74: 557–573, 2014
Piwi regulates Vasa accumulation during embryogenesis in the sea urchin
Authors: Yajima Mamiko , Gustafson Eric A. , Song Jia L. , Wessel Gary M.
Published: November 2013

Background: Piwi proteins are essential for germ line development, stem cell maintenance, and more recently found to function in epigenetic and somatic gene regulation. In the sea urchin Strongylocentrotus purpuratus, two Piwi proteins, Seawi and Piwi‐like1, have been identified, yet their functional contributions have not been reported. Results: Here we found that Seawi protein was localized uniformly in the early embryo and then became enriched in the primordial germ cells (PGCs) (the small micromere lineage) from blastula stage and thereafter. Morpholino knockdown of Sp‐seawi diminished PGC‐specific localization of Seawi proteins, and altered expression of other germ line markers such as Vasa and Gustavus, but had no effect on Nanos. Furthermore, Seawi knockdown transiently resulted in Vasa positive cell proliferation in the right coelomic pouch that appear to be derived from the small micromere lineage, yet they quickly disappeared with an indication of apoptosis by larval stage. Severe Seawi knockdown resulted in an increased number of apoptotic cells in the entire gut area. Conclusion: Piwi proteins appear to regulate PGC proliferation perhaps through control of Vasa accumulation. In this organism, Piwi is likely regulating mRNAs, not just transposons, and is potentially functioning both inside and outside of the germ line during embryogenesis. Developmental Dynamics 243:451–458, 2014. © 2013 Wiley Periodicals, Inc.
Human dendritic cells — stars in the skin
Authors: Klechevsky Eynav
Published: November 2013

“A properly functioning adaptive immune system signifies the best features of life. It is diverse beyond compare, tolerant without fail, and capable of behaving appropriately with a myriad of infections and other challenges. Dendritic cells (DCs) are required to explain how this remarkable system is energized and directed.” This is a quote by one of the greatest immunologists our community has ever known, and the father of dendritic cells, Ralph Steinman. Steinman's discovery of DCs in 1973 and his subsequent research opened a new field of study within immunology: DC biology and in particular the role of DCs in immune regulation in health and disease. Here, I review themes from our work and others on the complex network of dendritic cells in the skin and discuss the significance of skin DCs in understanding aspects of host defense against infections, the pathology of inflammatory skin diseases, and speculate on the future effective immune‐based therapies.
Synthesis and Characterization of the First Tetracyanamidogallate
Authors: Kalmutzki Markus , Ströbele Markus , Kroeker Scott , Wren John E. C. , Meyer H. Jürgen
Published: November 2013

A tetracyanamidogallate with the formula LiSr2[Ga(CN2)4] was prepared from stoichiometric mixtures of SrF2, GaF3, and Li2(CN2) in a fused silica tube. The formation of LiSr2[Ga(CN2)4] by solid‐state metathesis was studied by differential scanning calorimetry. A crystalline powder of LiSr2[Ga(CN2)4] was studied by X‐ray powder diffraction, and powder patterns were indexed isotypically to LiSr2[Al(CN2)4]. The crystal structure of LiSr2[Ga(CN2)4] was refined by single‐crystal X‐ray diffraction, thus indicating a disorder of Li+ and Ga3+ ions that was investigated by the means of 71Ga solid‐state magic‐angle spinning (MAS) NMR spectroscopic measurements and DFT calculations.
Axonal hyperexcitability after combined NGF sensitization and UV‐B inflammation in humans
Authors: Rukwied R. , Weinkauf B. , Main M. , Obreja O. , Schmelz M.
Published: November 2013

Background

Both nerve growth factor (NGF) and ultraviolet‐B (UV‐B) irradiation sensitize nociceptive nerve endings and increase axonal excitability of nociceptors. Combining NGF and UV‐B treatment is supra‐additive for sensory sensitization and even caused spontaneous pain in about 70% of the subjects.

Methods

UV‐B irradiation was performed at day 21 after intradermal NGF injection in 13 volunteers. Pain thresholds, electrically induced axon reflex erythema and pain (1.5‐fold pain threshold, 5–100 Hz) was analysed at days 22, 24, 28, 35, 49 and 70 and correlated to hyperalgesia and spontaneous pain.

Results

Electrical pain threshold after combined NGF/UVB was reduced below single treatment at 24 h but not at 72 h post‐UV‐B irradiation. At the NGF/UV‐B site, electrical pain was enhanced at all frequencies compared with single NGF and UV‐B sites at 24 and 72 h with pain ratings exceeding control values about twofold to threefold [65 ± 7 vs. 25 ± 8 visual analogue scale (VAS) (24 h) and 55 ± 9 vs. 22 ± 5 VAS (72 h)]. Hyperalgesia to electrical stimulation correlated with hyperalgesia to pinprick (Spearman r = 0.44; p < 0.001, Bonferroni corr.) and supra‐threshold heat (Spearman r = 0.55; p < 0.001) stimulation at 24 h only. Electrical pain thresholds at the NGF/UV‐B site weakly correlated to spontaneous pain levels (Spearman r = 0.3; p = 0.025, without Bonferroni correction). In contrast, electrically induced pain or axon reflex erythema did not correlate to spontaneous pain levels.

Conclusions

The combination of NGF and UV‐B increases axonal excitability that contributes to hyperalgesia and might also facilitate ongoing spontaneous pain.