bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of RNA-Seq data reveals involvement of JAK/STAT signalling during leg regeneration in the cricket Gryllus bimaculatus
Authors: Bando Tetsuya , Ishimaru Yoshiyasu , Kida Takuro , Hamada Yoshimasa , Matsuoka Yuji , Nakamura Taro , Ohuchi Hideyo , Noji Sumihare , Mito Taro
Published: January 2013

In the cricket Gryllus bimaculatus, missing distal parts of the amputated leg are regenerated from the blastema, a population of dedifferentiated proliferating cells that forms at the distal tip of the leg stump. To identify molecules involved in blastema formation, comparative transcriptome analysis was performed between regenerating and normal unamputated legs. Components of JAK/STAT signalling were upregulated more than twofold in regenerating legs. To verify their involvement, Gryllus homologues of the interleukin receptor Domeless (Gb’dome), the Janus kinase Hopscotch (Gb’hop) and the transcription factor STAT (Gb’Stat) were cloned, and RNAi was performed against these genes. Gb’domeRNAi, Gb’hopRNAi and Gb’StatRNAi crickets showed defects in leg regeneration. Blastema expression of Gb’cyclinE was decreased in the Gb’StatRNAi cricket compared with that in the control. Hyperproliferation of blastema cells caused by Gb’fatRNAi or Gb’wartsRNAi was suppressed by RNAi against Gb’Stat. The results suggest that JAK/STAT signalling regulates blastema cell proliferation during leg regeneration.
Smoke Gets in Your Eyes: Cigarette Tax Salience and Regressivity
Authors: Goldin Jacob , Homonoff Tatiana
Published: January 2013

Recent evidence suggests consumers pay less attention to commodity taxes levied at the register than to taxes included in a good's posted price. If this attention gap is larger for high-income consumers than for low-income consumers, policymakers can manipulate a tax's regressivity by altering the fraction of the tax imposed at the register. We investigate income differences in attentiveness to cigarette taxes, exploiting state and time variation in cigarette excise and sales tax rates. Whereas all consumers respond to taxes that appear in cigarettes' posted price, our results suggest that only low-income consumers respond to taxes levied at the register. (JEL D12, H22, H25, H71, L66)
The Mangalore Aircrash of 22 May 2010: Practical Problems Related to Identification of the Dead in a Populous Developing Country
Authors: Menezes Ritesh G , Shetty B Suresh Kumar , Rastogi Prateek , Padubidri Jagadish Rao , Babu YP Raghavendra , Nagesh KR , D'souza Deepak Herald , Shetty Mahabalesh , Monteiro Francis NP , Dsouza Haneil Larson
Published: January 2013

It was a sad and emotional moment for the citizens of Mangalore, India when the “Dubai to Mangalore” Air India Express Boeing 737-800 flight IX-812 crashed at the Mangalore International Airport on 22 May 2010, killing 158 people on board. Identification of the victims was difficult as most of the bodies were charred beyond easy recognition. The practical problems faced by the legal authorities in identifying the charred victims in a populous and developing country like India are discussed in this paper.
The Effect of Teaching Methods and Learning Style on Learning Program Design in Web-Based Education Systems
Authors: Hung Yen-Chu
Published: January 2013

The instructional value of web-based education systems has been an important area of research in information systems education. This study investigates the effect of various teaching methods on program design learning for students with specific learning styles in web-based education systems. The study takes first-year Computer Science and Information Engineering majors as the sample population. In an earlier study (Hung & Huang, 2008), Bayesian Network analysis of experimental data showed that students with “Input-oriented” and “Perception-oriented” learning styles performed less well on program design tests. Following on these results, this study further analyzes student learning performance in the program design course with a focus on the relationship between teaching methods and learning styles. Students are divided into experimental groups and a control group. The subjects' learning performances are analyzed with the bi-factor variable analysis in SPSS. The results indicate that (a) in learning program design, input-oriented students taught with the diagram method exhibit significantly better learning performance than those using other teaching methods; and (b) in learning program design, perception-oriented students taught with the analogy method exhibit significantly better learning performance than those using other teaching methods.
When Will College Truly Leave the Building: If MOOCs are the Answer, What is the Question?
Authors: Pence Harry E.
Published: January 2013

The Internet has disrupted or threatened to disrupt the traditional business models in many different areas, including publishing, record companies, retail sales, motion pictures, and advertising. One potential source of disruption for higher education is online learning, especially the recent focus on Massive Open Online Courses (MOOCs). Can MOOCs provide a less expensive substitute for face-to-face instruction, and will MOOCs represent such a major change in the learning process that they will be disruptive, eventually replacing traditional education methods? How should colleges and universities respond to online learning in general and MOOCs in particular?
The Value of Big N Target Auditors in Corporate Takeovers
Authors: Xie Yuan , Yi Han S. , Zhang Yinqi
Published: January 2013

Using a large sample between 1987 and 2006, we document that firms with Big N auditors are (1) more likely to become merger and acquisition (M&A) targets, and (2) more likely to be ultimately acquired in M&A deals. Cross-sectional analyses further suggest that the effects of Big N target auditors on the likelihood of becoming targets and on deal completion rates are more pronounced for firms with low accruals quality (our proxy for high information risk). Overall, the results emphasize the important role that Big N target auditors play in facilitating M&A transactions.

Data Availability: All data used in this study are publicly available from the sources identified in the paper.
Ice-volume changes, bias estimation of mass-balance measurements and changes in subglacial lakes derived by lidar mapping of the surface of Icelandic glaciers
Authors: Jóhannesson Tómas , Björnsson Helgi , Magnússon Eyjólfur , Guðmundsson Sverrir , Pálsson Finnur , Sigurðsson Oddur , Thorsteinsson Thorsteinn , Berthier Etienne
Published: January 2013

Icelandic glaciers cover ∼11 000 km2 in area and store ∼3600 km3 of ice. Starting in 2008 during the International Polar Year, accurate digital elevation models (DEMs) of the glaciers are being produced with airborne lidar. More than 90% of the glaciers have been surveyed in this effort, including Vatnajökull, Hofsjökull, Myrdalsjökull, Drangajökull, Eyjafjallajökull and several smaller glaciers. The publicly available DEMs are useful for glaciological and geological research, including studies of ice-volume changes, estimation of bias in mass-balance measurements, studies of jökulhlaups and subglacial lakes formed by subglacial geothermal areas, and for mapping of crevasses. The lidar mapping includes a 500-1000 m wide ice-free buffer zone around the ice margins which contains many glacio-geomorphological features, and therefore the new DEMs have proved useful in geological investigations of proglacial areas. Comparison of the lidar DEMs with older maps confirms the rapid ongoing volume changes of the Icelandic ice caps which have been shown by mass-balance measurements since 1995/96. In some cases, ice-volume changes derived by comparing the lidar measurements with older DEMs are in good agreement with accumulated ice-volume changes derived from traditional mass-balance measurements, but in other cases such a comparison indicates substantial biases in the traditional mass-balance records.
Advanced Glycation End Product (AGE)-AGE Receptor (RAGE) System Upregulated Connexin43 Expression in Rat Cardiomyocytes via PKC and Erk MAPK Pathways
Authors: Yu Lu , Zhao Yanbo , Xu Shengjie , Ding Fang , Jin Chongying , Fu Guosheng , Weng Shaoxiang
Published: January 2013

The remodeling of cardiac gap junction contributes to the arrhythmias in a diabetic heart. We previously reported that high glucose reduced Cx43 protein level in neonatal rat cardiomyocytes. But, the effect and mechanisms of advanced glycation end product (AGE) on Cx43 expression still remain unclear. In this study, we measured the AGE receptor (RAGE) and Cx43 expression by immunohistochemisty in AGE-infused Sprague-Dawley (SD) rats. In vitro, the Cx43 and RAGE levels were detected in AGE-treated cardiomyocytes by Western blot and real-time RT-PCR. The function of cells coupling was measured by Scrap loading dye transfer assay. Our results showed that the AGE-infused rat hearts exhibited increased cardiac RAGE and Cx43, as well as Cx43 redistribution. In cultured cardiomyocytes, AGE elevated RAGE expression in a time- and dose-dependent manner. Cx43 protein and mRNA levels were upregulated by AGE (200 mg/L, 24 h), but the gap junction function was not enhanced. RAGE-targeted knock-down or the addition of PKC, and Erk inhibitors abolished the effect of AGE on Cx43. Therefore, AGE-RAGE system might elevate Cx43 expression in rat cardiomyocytes by activating PKC and Erk MAPK pathways, and it also enhanced Cx43 redistribution in vivo, which might contribute to the arrhythmias in diabetes.
Connecting Chromatin Modifying Factors to DNA Damage Response
Authors: Lai Weiwei , Li Hongde , Liu Shuang , Tao Yongguang
Published: January 2013

Cells are constantly damaged by factors that can induce DNA damage. Eukaryotic cells must rapidly load DNA repair proteins onto damaged chromatin during the DNA damage response (DDR). Chromatin-remodeling complexes use the energy from ATP hydrolysis to remodel nucleosomes and have well-established functions in transcription. Emerging lines of evidence indicate that chromatin-remodeling complexes are important and may remodel nucleosomes during DNA damage repair. New studies also reveal that ATP-dependent chromatin remodeling is involved in cell cycle progression, signal transduction pathways, and interaction and modification of DDR-related proteins that are specifically and intimately connected with the process of DNA damage. This article summarizes the recent advances in our understanding of the interplay between chromatin remodeling and DNA damage response.
Surface Appendages of Archaea: Structure, Function, Genetics and Assembly
Authors: Jarrell Ken , Ding Yan , Nair Divya , Siu Sarah
Published: January 2013

Organisms representing diverse subgroupings of the Domain Archaea are known to possess unusual surface structures. These can include ones unique to Archaea such as cannulae and hami as well as archaella (archaeal flagella) and various types of pili that superficially resemble their namesakes in Bacteria, although with significant differences. Major advances have occurred particularly in the study of archaella and pili using model organisms with recently developed advanced genetic tools. There is common use of a type IV pili-model of assembly for several archaeal surface structures including archaella, certain pili and sugar binding structures termed bindosomes. In addition, there are widespread posttranslational modifications of archaellins and pilins with N-linked glycans, with some containing novel sugars. Archaeal surface structures are involved in such diverse functions as swimming, attachment to surfaces, cell to cell contact resulting in genetic transfer, biofilm formation, and possible intercellular communication. Sometimes functions are co-dependent on other surface structures. These structures and the regulation of their assembly are important features that allow various Archaea, including thermoacidophilic, hyperthermophilic, halophilic, and anaerobic ones, to survive and thrive in the extreme environments that are commonly inhabited by members of this domain.
Case Studies of the Synthesis of Bioactive Cyclodepsipeptide Natural Products
Authors: Stolze Sara , Kaiser Markus
Published: January 2013

Cyclodepsipeptide natural products often display intriguing biological activities that along with their complex molecular scaffolds, makes them interesting targets for chemical synthesis. Although cyclodepsipeptides feature highly diverse chemical structures, their synthesis is often associated with similar synthetic challenges such as the establishment of a suitable macrocyclization methodology. This review therefore compiles case studies of synthetic approaches to different bioactive cyclodepsipeptide natural products, thereby illustrating obstacles of cyclodepsipeptide synthesis as well as their overcomings.
Antioxidants Improve the Phenotypes of Dilated Cardiomyopathy and Muscle Fatigue in Mitochondrial Superoxide Dismutase-Deficient Mice
Authors: Koyama Hirofumi , Nojiri Hidetoshi , Kawakami Satoru , Sunagawa Tadahiro , Shirasawa Takuji , Shimizu Takahiko
Published: January 2013

Redox imbalance elevates the reactive oxygen species (ROS) level in cells and promotes age-related diseases. Superoxide dismutases (SODs) are antioxidative enzymes that catalyze the degradation of ROS. There are three SOD isoforms: SOD1/CuZn-SOD, SOD2/Mn-SOD, and SOD3/EC-SOD. SOD2, which is localized in the mitochondria, is an essential enzyme required for mouse survival, and systemic knockout causes neonatal lethality in mice. To investigate the physiological function of SOD2 in adult mice, we generated a conditional Sod2 knockout mouse using a Cre-loxP system. When Sod2 was specifically deleted in the heart and muscle, all mice exhibited dilated cardiomyopathy (DCM) and died by six months of age. On the other hand, when Sod2 was specifically deleted in the skeletal muscle, mice showed severe exercise disturbance without morphological abnormalities. These provide useful model of DCM and muscle fatigue. In this review, we summarize the impact of antioxidants, which were able to regulate mitochondrial superoxide generation and improve the phenotypes of the DCM and the muscle fatigue in mice.
RETRACTED: Cytotoxicity and Anti-Inflammatory Activity of Methylsulfanyl-Triazoloquinazolines
Authors: Al-Salahi Rashad , Gamal-Eldeen Amira , Alanazi Amer , Al-Omar Mohamed , Marzouk Mohamed , Fouda Moustafa
Published: January 2013

A series of twenty five 2-methylsulfanyl-[1,2,4]triazolo[1,5-a]quinazoline derivatives 1–25 was previously synthesized. We have now investigated their cytotoxic effects against hepatocellular Hep-G2 and colon HCT-116 carcinoma cells and effect on the macrophage growth, in addition to their influence of the inflammatory mediators [nitric oxide (NO), tumor necrosis factor-α (TNF-α), prostaglandin E-2 (PGE-2) and in bacterial lipopolysachharide (LPS)-stimulated macrophages]. The findings revealed that compounds 13 and 17 showed the highest cytotoxicity and that 3, 6–8 and 25 are promising multi-potent anti-inflammatory agents.
Scour Monitoring System for Subsea Pipeline Based on Active Thermometry: Numerical and Experimental Studies
Authors: Zhao Xuefeng , Li Weijie , Song Gangbing , Zhu Zuo , Du Jun
Published: January 2013

A scour monitoring system for subsea pipeline based on active thermometry is proposed in this paper. The temperature reading of the proposed system is based on a distributed Brillouin optical fiber sensing technique. A thermal cable acts as the main component of the system, which consists of a heating belt, armored optical fibers and heat-shrinkable tubes which run parallel to the pipeline. The scour-induced free span can be monitored through different heat transfer behaviors of in-water and in-sediment scenarios during heating and cooling processes. Two sets of experiments, including exposing different lengths of the upper surface of the pipeline to water and creating free spans of various lengths, were carried out in laboratory. In both cases, the scour condition was immediately detected by the proposed monitoring system, which confirmed the system is robust and very sensitive. Numerical study of the method was also investigated by using the finite element method (FEM) with ANSYS, resulting in reasonable agreement with the test data. This brand new system provides a promising, low cost, highly precise and flexible approach for scour monitoring of subsea pipelines.
Recommendations for Fasting in Ramadan for Patients on Peritoneal Dialysis
Authors: Wakeel Jamal Al , Mitwalli Ahmed H. , Alsuwaida Abdulkareem , Ghonaim Mohammad Al , Usama Saira , Hayat Ashik , Shah Iqbal Hamid
Published: January 2013

♦Introduction

The month of Ramadan holds great religious and social significance for Muslims all over the world. The aim of the present study was to provide a modified dialysis schedule for peritoneal dialysis (PD) patients that allows for fasting and that minimizes the effect on the patient's general health and volume status.

♦Methods

We observed 31 patients under treatment at the PD unit of King Khalid University Hospital, King Saud University, Riyadh. During the 3 - 4 weeks before the start of Ramadan, all patients were counseled individually and in detail about the possibility of fasting. They were also provided with clear instructions about fluid intake (up to 1 L daily) and avoiding a high-potassium diet. Of the 31 patients, 18 (10 women, 8 men) elected to fast during the month of Ramadan. The mean duration of fast in the study year (2009) in Riyadh, Saudi Arabia, was about 14 hours: from 0415 h (before sunrise) to 1800 h (after sunset). Depending on membrane type and patient preference, the fasting group was shifted to one of two regimens: • Modified continuous ambulatory PD (8 patients): 3 exchanges during the night (1.36% or 2.27%), and icodextrin for a long dwell during the day. The first dialysis exchange was performed immediately after breaking the fast (1900 h), and the next at 2300 h. The final exchange was performed in the early morning before sunrise (0300 h), when the icodextrin was infused. • Modified continuous cycling PD (10 patients): exchanges (1.36% or 2.27%) were performed over 6 - 7 hours, and icodextrin was infused for a long dwell during the day. The patient connected to the cycler at 2000 h or 2100 h, and therapy finished at nearly 0300 h, with icodextrin as the last fill.

♦Results

Of the study patients, 2 were admitted because of peritonitis (1 in each modality group), and the modified therapy was discontinued. In the modified CCPD group, 1 patient (on PD for 1 month before Ramadan) developed PD-related pleural effusion (proved by pleural fluid analysis), and PD was consequently discontinued. Hypotension developed in 2 patients of the CAPD group and 1 of the CCPD group during the first 2 weeks. In the CCPD group, 1 patient presented with lower limb edema and mild fluid overload. Overall, PD patients that opted to fast during Ramadan did not experience any serious morbidity or deterioration in renal function during their period of observance. No biochemical parameters or clearance studies showed a statistically significant p value.

♦Conclusions

In view of the study findings, we conclude that most stable patients on PD can fast, provided that they strictly adhere to their medications and dialysis therapy in addition to the dietary restrictions. These patients should be followed closely to detect any complications and to ensure that adequate fluid and electrolyte balance are maintained.
Sox4 Is Required for the Survival of Pro-B Cells
Authors: Sun Baohua , Mallampati Saradhi , Gong Yun , Wang Donghai , Lefebvre Véronique , Sun Xiaoping
Published: January 2013

The development of mature B cells from hematopoietic stem cells is a strictly orchestrated process involving multiple regulatory genes. The transcription factor Sox4 is required for this process, but its role has not been systematically studied, and the underlying mechanisms remain unknown. To determine when and how Sox4 functions in the stepwise process of B cell development, we used mice harboring conditional null alleles for Sox4 and a Cre transgene. Sox4 deletion in hematopoietic stem cells almost entirely eliminated pro-B cells in both fetal livers and adult bone marrow, resulting in a severe deficiency in later stage B cells, including circulating mature B cells. Sox4-deficient pro-B cells, particularly those expressing the stem cell factor receptor c-Kit, readily underwent apoptosis, and even more so when c-Kit activity was inhibited by imatinib. C-Kit–expressing pro-B cells showed decreased activation of the c-Kit downstream protein Src upon Sox4 deletion. Likewise, the level of the anti-apoptotic Bcl2 protein was decreased in residual pro-B cells, and its restoration using a Bcl2 transgene allowed not only partial rescue of pro-B cell survival but also B cell maturation in the absence of Sox4. Our findings indicate that Sox4 is required for the survival of pro-B cells and may functionally interact with c-Kit and Bcl2.
Cutting Edge: Antibody-Dependent Memory-like NK Cells Distinguished by FcRγ Deficiency
Authors: Zhang Tianxiang , Scott Jeannine M. , Hwang Ilwoong , Kim Sungjin
Published: January 2013

Because NK cells lack gene-recombination machinery and are thought to be relatively short-lived, it is unclear whether NK cells can mount long-term effective recall responses to reinfections by diverse pathogens. In this article, we report that FcRγ-deficient NK cells, which we recently identified and termed g−NK cells, possess distinct memory features directed by FcR-mediated Ab-dependent target recognition. The presence of g−NK cells was associated with prior human CMV (HMCV) infection, yet g−NK cell responses were not restricted to HCMV-infected target cells. In the presence of virus-specific Abs, g−NK cells had greatly enhanced functional capabilities, superior to conventional NK cells, and were highly responsive to cells infected with either HCMV or HSV-1. Remarkably, the g−NK cell subset persisted long-term at nearly constant levels in healthy individuals. Therefore, FcRγ deficiency distinguishes an Ab-dependent memory-like NK cell subset with enhanced potential for broad antiviral responses.
Development and impact of hooks of large droplet concentration on remote southeast Pacific stratocumulus
Authors: George R. C. , Wood R. , Bretherton C. S. , Painter G.
Published: January 2013

Abstract. Over the southeastern Pacific (SEP), droplet concentration (Nd) in the typically unpolluted marine stratocumulus west of 80° W (> 1000 km offshore) is periodically strongly enhanced in zonally-elongated "hook"-shaped arcs that increase albedo. Here, we examine three hook events using the chemistry version of the Weather Research and Forecasting model (WRF-Chem) with 14 km horizontal resolution, satellite data and aircraft data from the VAMOS Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx). A particularly strong hook yields insights to the development, decay, and radiative impact of these features. Hook development occurs with Nd increasing to polluted levels over the remote ocean primarily due to entrainment of cloud condensation nuclei (CCN) from the free troposphere (FT). The feature advects northwestward until the FT CCN source is depleted, after which Nd decreases over a few days due to precipitation and dilution. The model suggests that the FT CCN source supplying the hook consists of high concentrations of small accumulation mode aerosols that contribute a relatively small amount of aerosol mass to the MBL. The aerosol particles originate mainly from a pulse of offshore flow that transports Santiago region (33–35° S) emissions to the marine FT. To provide a sustained hook CCN source, the FT transport of pollution plumes to the remote ocean requires strong, deep offshore flow. Such flow is favored by a trough approaching the South American coast and a southeastward shift of the climatological subtropical high pressure system. The model simulations show precipitation suppression in the hook and a corresponding increase in liquid water path (LWP) compared with a simulation without anthropogenic sources. LWP also increases in time as the hook evolves due to increasing stability and decreasing subsidence. WRF-Chem suggests that DMS significantly influences the aerosol number and size distributions in a hook, but that hooks do not form without FT CCN. The Twomey effect contributes ~ 50–70% of the albedo increase due the presence of the hook, while secondary aerosol indirect effects and meteorological influences also contribute significantly. The source of hook aerosols is difficult to determine with the available observations alone. The model explains the observations and puts them in context of the factors influencing hook formation. Two other weaker hooks during VOCALS-REx are not as well simulated but are also associated with FT offshore flow near Santiago. Hooks demonstrate the importance of free-tropospheric transport of aerosols in modulating the droplet concentration in the southeastern Pacific stratocumulus deck, and present a formidable challenge to simulate accurately in large scale models.
Validation of ozone monthly zonal mean profiles obtained from the Version 8.6 Solar Backscatter Ultraviolet algorithm
Authors: Kramarova N. A. , Frith S. M. , Bhartia P. K. , McPeters R. D. , Taylor S. L. , Fisher B. L. , Labow G. J. , DeLand M. T.
Published: January 2013

Abstract. We present validation of ozone profiles from a number of Solar Backscatter Ultraviolet (SBUV and SBUV/2) instruments that were recently reprocessed using an updated (Version 8.6) algorithm. The SBUV data record spans a 41-yr period from 1970 to 2011 with a 5-yr gap in the 1970s. The ultimate goal is to create a consistent, well-calibrated dataset of ozone profiles that can be used for climate studies and trend analyses. SBUV ozone profiles have been intensively validated against satellite profile measurements from the Microwave Limb Sounders (MLS) (on board UARS and Aura satellites) and the Stratospheric Aerosol and Gas Experiment (SAGE II) and ground-based observations from the microwave spectrometers, lidars, Umkehr instruments and balloon-borne ozonesondes. In the stratosphere between 25 and 1 hPa the mean biases and standard deviations are mostly within 5% for monthly zonal mean ozone profiles. Above and below this layer the vertical resolution of the SBUV algorithm decreases. We combine several layers of data in the troposphere/lower stratosphere to account for the lower resolution. The bias in the SBUV tropospheric/lower stratospheric combined layer relative to similarly integrated columns from Aura MLS, ozonesonde and Umkehr instruments varies within 5%. We also estimate drifts in the SBUV instruments and their potential effect on the long-term stability of the combined data record. Data from the SBUV instruments that collectively cover the 1980s and 2000s are very stable, with drifts mostly less than 0.5% yr−1. The features of individual SBUV(/2) instruments are discussed and recommendations for creating the merged SBUV data set are provided.
Size distributions of mineral aerosols and dust emission flux observed over Horqin Sandy Land area in northern China
Authors: Li X. , Zhang H. S.
Published: January 2013

Abstract. Size distribution of mineral aerosols is of primary importance in determining their residence time in atmosphere, transport patterns, removal mechanisms as well as their effects on climate and human health. This study aims to obtain dust particle size distribution and size-resolved dust emission flux under different weather conditions over a sandy land area in northern China (Horqin Sandy Land, Inner Mongolia), using the observational data from Horqin sandstorm monitoring station in the spring of 2010 and 2012. Dust (PM20) mass concentration was measured by a 10-stage quartz crystal microbalance (QCM) cascade impactor. The statistical results indicate that finer dust particles (r ≤ 1.0 μm) take a large proportion of all PM20 concentration under clear-day conditions, while coarser dust particles (r ≥ 2.5 μm) concentration increased under dust-day conditions, with the peak occurring between 4–7 μm. The dust particle size distributions during the pre-dust-emission and dust-emission periods of a dust event on 7 April 2012 have similar features to the statistical results. During the dust event, the magnitude of dust emission flux of all sizes increased about one or two orders (0.1–10 μg m−2 s−1) as u* increase from 0.54 to 1.29 m s−1. The maximum total F value was about 43.0 μg m−2 s−1 and the maximum size-resolved F(Ddi) is 12.3 μg m−2 s−1 in 0.3–0.45 μm size bin when u* is 1.29 m s−1. Dust advection has effects on airborne dust size distribution, making the proportion of dust particles of different sizes more uniform, as observed in a non-local dust event on 19 April 2012.
A numerical study of orographic forcing on TC Dina (2002) in South West Indian Ocean
Authors: Jolivet S. , Chane-Ming F. , Barbary D. , Roux F.
Published: January 2013

Abstract. Using the French non-hydrostatic mesoscale numerical model Méso-NH, intense tropical cyclone (TC) Dina (2002) is simulated to investigate the forcing caused by the steep orography of Réunion island (20.8° S, 55.5° E) in the southwest Indian Ocean. The model initialised by a bogus vortex derived from Doppler radar observations reproduces quite well the dynamical characteristics of TC Dina approaching the island and provides some clues on the orographic influence on the structure and the evolution of the TC. The presence of the island is observed to stabilise the cyclonic circulation by damping the natural elliptical eyewall rotation and forcing the flow circulation. Initially, the cyclonic flow is blocked upwind of the orography which induces a convergence associated with upward vertical velocities, intense precipitation and maximum horizontal winds along the upwind slopes of the island. A mountain wave, generated over the highest terrains, is associated with downward motions on the lee side. When the strongest winds reach the island, the flow changes its behaviour from passing around to over the island. Non-dimensional flow parameters in agreement with recent theories are calculated to explain TC track.
Four-dimensional evaluation of regional air quality models
Authors: Solazzo E. , Bianconi R. , Pirovano G. , Moran M. D. , Vautard R. , Hogrefe C. , Matthias V. , Grossi P. , Appel K. W. , Bessagnet B. , Brandt J. , Chemel C. , Christensen J. H. , Forkel R. , Francis X. V. , Hansen A. , McKeen S. , Nopmongcol U. , Prank M. , Sartelet K. N. , Segers A. , Silver J. D. , Yarwood G. , Werhahn J. , Zhang J. , Rao S. T. , Galmarini S.
Published: January 2013

Abstract. The evaluation of regional air quality models is a challenging task, not only for the intrinsic complexity of the topic but also in view of the difficulties in finding sufficiently abundant, harmonized and time/space-well-distributed measurement data. This study, conducted in the framework of AQMEII (Air Quality Model Evaluation International Initiative), evaluates 4-D model predictions obtained from 15 modelling groups and relating to the air quality of the full year of 2006 over the North American and European continents. The modelled variables are ozone, CO, wind speed and direction, temperature, and relative humidity. Model evaluation is supported by the high quality in-flight measurements collected by instrumented commercial aircrafts in the context of the MOZAIC programme. The models are evaluated at five selected domains positioned around major airports, four in North America (Portland, Philadelphia, Atlanta, Dallas) and one in Europe (Frankfurt). Due to the extraordinary scale of the exercise (number of models and variables, spatial and temporal extent), this study is primarily aimed at illustrating the potential for using MOZAIC data for regional-scale evaluation and the capabilities of models to simulate concentration and meteorological fields in the vertical rather than just at the ground. We apply various approaches, metrics, and methods to analyze this complex dataset. Results of the investigation indicate that, while the observed meteorological fields are modelled with some success, modelling CO in and above the boundary layer remains a challenge and modelling ozone also has room for significant improvement. We note, however, that the high sensitivity of models to height, season, location, and metric makes the results rather difficult to interpret and to generalize. With this work, though, we set the stage for future process-oriented and in-depth diagnostic analyses.
Transit and residence times in the surface Adriatic Sea as derived from drifter data and Lagrangian numerical simulations
Authors: Poulain P.-M. , Hariri S.
Published: January 2013

Abstract. Statistics of transit and residence times in the surface Adriatic Sea, a semi-enclosed basin of the Mediterranean, are estimated from drifter data and Lagrangian numerical simulations. The results obtained from the drifters are generally underestimated given their short operating lifetimes (half life of ~ 40 days) compared to the transit and residence times. This bias can be removed by considering a large amount of numerical particles whose trajectories are integrated over a long time (750 days) with a statistical advection-diffusion model of the Adriatic surface circulation. Numerical particles indicate that the maximum transit time to exit the basin is about 216–260 days for objects released near the northern tip of the Adriatic, and that a particle entering on the eastern Otranto Channel will typically exit on the other side of the Channel after 170–185 days. A value of 150–168 days is estimated for the residence time in the Adriatic basin.
Reprocessed height time series for GPS stations
Authors: Rudenko S. , Schön N. , Uhlemann M. , Gendt G.
Published: January 2013

Abstract. Precise weekly positions of 403 Global Positioning System (GPS) stations located worldwide are obtained by reprocessing GPS data of these stations for the time span from 4 January 1998 until 29 December 2007. The processing algorithms and models used as well as the solution and results obtained are presented. Vertical velocities of 266 GPS stations having a tracking history longer than 2.5 yr are computed; 107 of them are GPS stations located at tide gauges (TIGA observing stations). The vertical velocities calculated in this study are compared with the estimates from the co-located tide gauges and other GPS solutions. The formal errors of the estimated vertical velocities are 0.01–0.80 mm yr−1. The vertical velocities of our solution agree within 1 mm yr−1 with those of the recent solutions (ULR5 and ULR3) of the Université de La Rochelle for about 67–75 per cent of the common stations. Examples of typical behaviour of station height changes are given and interpreted. The derived height time series and vertical motions of continuous GPS at tide gauges stations can be used for correcting the vertical land motion in tide gauge records of sea level changes.
Gestão do Conhecimento e Complexidade
Authors: Neto Ivan Rocha
Published: January 2013

Este ensaio tem por objetivo propor uma revisão crítica sobre Estado da Arte da teoria e prática de Gestão do Conhecimento (GC) sob o ponto de vista do pensamento complexo. Com estes propósitos foram feitas buscas em várias bases de informação, restringindo as ocorrências aos últimos cinco anos (2007-2011), com as palavras chaves exatas, apenas nos títulos das publicações segundo o aplicativo Program Files \Harzing's Publish or Perish 3. Esta proposta tem origem nas discussões atuais a respeito das possibilidades e limitações teóricas, práticas e de pesquisa sobre a Gestão do Conhecimento, que têm normalmente sido olhadas segundo a ótica positivista e cartesiana de alguns autores contemporâneos, mas que pode ser estudada do ponto de vista da teoria da complexidade, sendo um campo de investigação deveras promissor.DOI:10.5585/gep.v3i1.41
Classificação de Projetos: Um Estudo da Aplicação do Método AHP
Authors: De Cavalho Kahan Monteiro , Pessôa Leonel Cesarino
Published: January 2013

O presente Relato Técnico trata da classificação de projetos, processo que possibilita o gerenciamento do portfólio da carteira de projetos da organização. Traz a analise de um dos modelos consagrados de classificação, o método Analytic Hierarchy Process (AHP), estudado a partir de um problema encontrado em um caso real. A unidade de análise escolhida foi o departamento de inovação de uma instituição pública de ensino superior, devido à necessidade organizacional em empregar uma ferramenta no processo de classificação de projetos de pesquisa, que utilize critérios objetivos. O trabalho tem como objetivo central apontar uma solução para este problema comumente enfrentado pelas organizações. E, com isso, pretende responder ao problema de pesquisa: “Como o método AHP contribui para priorização de projetos de forma objetiva?”. Como estratégias de pesquisa foram utilizadas a pesquisa bibliográfica e a pesquisa-ação.DOI:10.5585/gep.v3i1.89
Band Configuration of SiO2/m-Plane ZnO Heterointerface Correlated with Electrical Properties of Al/SiO2/ZnO Structures
Authors: Liu Jiangwei , Kobayashi Atsushi , Ueno Kohei , Ohta Jitsuo , Fujioka Hiroshi , Oshima Masaharu
Published: January 2013

SiO2films have been deposited onm-plane ZnO(1100) substrates by atomic layer deposition method at 200 °C and the interface has been investigated. Band structures of amorphous SiO2/m-plane ZnO(1100) heterointerface have been characterized by X-ray photoelectron spectroscopy, showing type I band configuration with valence and conduction band offsets of 1.7±0.2 and 3.6±0.2 eV, respectively. Capacitance–voltage (C–V) measurements of Al/SiO2/m-plane ZnO(1100) have been performed. When gate bias was swept from positive to negative, a ledge appeared in theC–Vcurve of the Al/SiO2/m-plane ZnO structure, which is probably due to the emission of electrons trapped at the near-midgap deep levels. However, it is found that the surface treatment for ZnO using HCl yielding automatically flat stepped and terraced surface improves theC–Vcurve without the ledge.
Transitional Reorientation and Rotation of Molecules during Vector Holographic Recording in Azobenzene-Containing Polymeric Films
Authors: Ono Hiroshi , Izawa Masahiro , Sasaki Tomoyuki , Noda Kohei , Nishioka Emi , Kawatsuki Nobuhiro
Published: January 2013

We have carried out experimental and theoretical characterization of the dynamics of the vector holographic recording in azobenzene-containing polymeric films by observation of the temporal polarization states of the diffraction beams. Two types of mechanisms, i.e., linear polarization induced birefringence and migration induced rotation birefringence, are introduced in the present paper, and transitional reorientation and rotation of molecules during vector holographic recording in azobenzene-containing polymeric films are successfully determined.
Characterization of Three-Dimensional Magnetic Alignment for Magnetically Biaxial Particles
Authors: Yamaguchi Masuhiro , Ozawa Shun , Yamamoto Isao , Kimura Tsunehisa
Published: January 2013

The three-dimensional magnetic alignment (3DMA) is analytically investigated for magnetically biaxial particles with the susceptibility χ1>χ2>χ3in an amplitude-modulated (AM) elliptic field B= i1Bb1cos ωt+ i2Bb2sin ωtas a prototype method for 3DMA. The distribution function and the biaxial ordering matrix are numerically calculated by the Boltzmann distribution and the rotational diffusion equation. The 3DMA attains the optimum performance in the rapid rotation regime (RRR) with the infinity rotation frequency ω while the RRR is effectively available at lower rotation frequencies. The intermediate magnetization axis χ2is inferior to the easy and hard magnetization axes χ1and χ3in the time development and the equilibrium state of alignment. In all the methods for 3DMA, the dynamic and equilibrium behavior in the RRR are universally characterized by the reduced energy α=V(Bb1)2(χ3- χ1)/(2µ0kBT), the biaxial deviation of susceptibilityk= (χ2-χ1)/(χ3-χ1), the field modulation factorq= (b2/b1)2, and the reduced timetr= | α|DtwhereDis the rotational diffusion constant.
High-Throughput and High-Intensive Biosensor Microarray Fabrication by Selective Dewetting on a Wettability Controlled Substrate
Authors: Kim Jongsu , Park Hyunkyu , Kang Bongchul , Ham Chulho , Lee Hyeonhwa , Yang Minyang
Published: January 2013

In a microarray biosensor, the surface characteristic for reducing background nonspecific binding is a critical aspect for achieving the high sensitivity and accurate detection. In this paper, we proposed a new high-intensity and reduced nonspecific binding microarray fabrication method with a selective dewetting process on a mixed self-assembled monolayer (SAM), consisting of methyl-terminated and methoxy-[poly(ethylene glycol) (PEG)]-terminated silanes. The combination of hydrophobic and hydrophilic properties of the mixed SAM background layer provided the hydrophobicity that allowed the selective dewetting of the protein solution at specific versus nonspecific regions and reduced the nonspecific binding owing to hydrated PEG chains in the mixed SAM. The wiping process was applied for obtaining high throughput and reducing protein usage. Finally, the background non-specific binding was significantly reduced by 78% with a selective dewetting method compared with the standard method using a cover slip. Furthermore, the peak intensity was increased by 20% and the protein usage was reduced versus the standard method.
H2/N2 Plasma Etching Rate of Carbon Films Deposited by H-Assisted Plasma Chemical Vapor Deposition
Authors: Urakawa Tatsuya , Torigoe Ryuhei , Matsuzaki Hidefumi , Yamashita Daisuke , Uchida Giichiro , Koga Kazunori , Shiratani Masaharu , Setsuhara Yuichi , Takeda Keigo , Sekine Makoto , Hori Masaru
Published: January 2013

Etching resistance of carbon films deposited by plasma chemical vapor deposition (CVD) is one of the concerns to fabricate nanostructures using such carbon films as protective coating films and dummy films. We have carried out H2/N2 plasma etching of carbon films deposited by using an H-assisted plasma CVD method. The etching rate of carbon films decreases exponentially with increasing the mass density of carbon films from 1.51 to 2.27 g/cm3. The mass density of carbon films is the key parameter to tune the etching resistance.
Electrical Properties of ZnO-Doped Nd(Co1/2Ti1/2)O3 Thin Films Prepared by RF Magnetron Sputtering
Authors: Hsu Cheng-Hsing , He Yi-Da
Published: January 2013

The electrical properties and microstructures of ZnO-doped Nd(Co1/2Ti1/2)O3 thin films prepared by rf-magnetron sputtering on indium tin oxide (ITO)/glass substrates at different rf powers and Ar/O2 ratios have been investigated. X-ray diffraction pattern analysis showed that the deposited films exhibited a polycrystalline microstructure. All films exhibited the ZnO-doped Nd(Co1/2Ti1/2)O3 orientation perpendicular to the substrate surface, and the uniformity of surface morphologies of the film increased with decreasing Ar partial pressure and rf power. At an Ar/O2 ratio of 80/20 and a rf power of 250 W, the ZnO-doped Nd(Co1/2Ti1/2)O3 films possess a dielectric constant of 28.6 at 1 kHz, a dissipation factor of 0.02 at 1 kHz, and a leakage current density of 3.6×10-10 A/cm2 at an electrical field of 20 kV/cm.
Development of the Hybrid Conjugated Polymer Solar Cell Based on GaN Quantum Dots
Authors: Kim Minji , Shin Min Jeong , Gwon Dongoh , Ahn Hyung Soo , Yi Sam Nyung , Kim Pan Seok , Yoon Sung Cheol , Lee Changjin , Park Jungsik , Shin Keesam , Ha Dong Han , Sawaki Nobuhiko
Published: January 2013

We report the hybrid p–n junction based on GaN quantum dots (QDs) as an electron transport layer and poly(3-hexylthiophene-2,5-diyl) (P3HT) as a hole transport layer, which has not been tried for the solar cell until now. The growth of GaN QDs was achieved by the hydride vapor phase epitaxy (HVPE) technique and P3HT film sequentially was coated on the top of QDs. The overall performance of P3HT/GaN QDs hybrid heterojunction was analyzed by current density–voltage (J–V) characteristics and finally exhibited an open-circuit voltage, short-circuit current density, and fill factor of 160 mV, 3.6 mA/cm2, and 0.25, respectively. Also, its efficiency was shown up to 0.14% in an active area of 0.04 cm2 under AM1.5G illumination with an intensity of 100 mW cm-2. In this paper, we discuss the factors which affect the power conversion efficiency for future works.
Analysis of Dislocations Generated during Metal–Organic Vapor Phase Epitaxy of GaN on Patterned Templates
Authors: Suihkonen Sami , Ali Muhammad , Törmä Pekka T. , Sintonen Sakari , Svensk Olli , Sopanen Markku , Lipsanen Harri , Nevedomsky Vladimir N. , Bert Nikolay A.
Published: January 2013

We report on patterning and subsequent metal–organic vapor phase epitaxy overgrowth of GaN films on patterned GaN/sapphire templates. Templates with a hexagonal hole pattern were prepared by photolithography and dry etching. After GaN overgrowth voids were formed at the GaN/sapphire interface. Threading dislocations were found to bend and terminate at void sidewalls during the overgrowth resulting in improved material quality. The dislocations were analyzed by transmission electron microscopy combined with energy dispersive X-ray spectroscopy. Areas with increased Ga concentration were found at the tips of coalesced voids that introduced additional dislocations to the overgrown films.
Ultraviolet Photodetectors Using Transparent Gate AlGaN/GaN High Electron Mobility Transistor on Silicon Substrate
Authors: Narita Tomotaka , Wakejima Akio , Egawa Takashi
Published: January 2013

In this paper, UV photoconductivity of a transparent gate AlGaN/GaN high electron mobility transistor (HEMT) on a Si substrate is demonstrated. The transparent gate enables the HEMT to standby under pinch-off conditions for operation as a photodetector. Therefore, the device can overcome the drawback of high standby-current in conventional metal gate field-effect transistor (FET)-based photodetectors without sacrificing its high responsivity. A negative threshold-voltage shift of -0.25 V and a significant drain-current increase over two orders of magnitude were observed under UV-light irradiation condition from the surface-side. A high responsivity of 2.0×105 A/W at 360 nm with a low leakage current of 3×10-6 A/mm was simultaneously achieved. These experimental results were in agreement with the models for generation of a photo carrier and its transportation in a heterostructure.
Low Dislocation Densities of Nitride-Based Light-Emitting Diodes with a Preflow of NH3Source before Growth of AlN Buffer Layer
Authors: Wang Chun-Kai , Chiou Yu-Zung , Sun De-Jun , Chiang Tsung-Hsun
Published: January 2013

In this study, the AlN buffer layer grown onc-plane sapphire (Al2O3) substrates by metal–organic chemical vapor deposition (MOCVD) was controlled by a preflow of the NH3source. With the treatment of NH3preflow, the monolayer of AlN was formed on the surface of a sapphire substrate by the decomposition of the NH3source and Al2O3substrate. It was found that the density of threading dislocations significantly decreased owing to the abatement of lattice mismatch between a GaN layer and a sapphire substrate. At an injection current of 350 mA, the light output intensity of the light-emitting diode (LED) with NH3preflow was increased by 14.1% compared with that of a conventional LED. On the other hand, LEDs with NH3preflow treatment could endure electrostatic discharge (ESD) surges up to -3000 V and caused a low rate of light output degradation at a high ambient temperature.