bluuebunny/crossref_metadata_2025 huggingface dataset:
Family Ownership and Firm Performance
Authors: Dharmadasa Pradeep
Published: April 2015

Numerous studies have focused on ownership structure and firm performance. In recent years a growing amount of research has recognized the importance of family-controlled firms (FCFs) where ownership concentrates on single individual or family. Despite many important insights, however, significant gaps in the literature remain. Studies have produced divergent findings about the performance of FCFs, leading to calls for further research. Utilizing 151 and 753 firm-years of FCFs drawn from the Colombo Stock Exchange, Sri Lanka, and the Tokyo Stock Exchange, Japan, respectively during 2011-2013, this study examines the relationship between family ownership and firm performance. Regression results show conflicting findings in that family ownership has a positive relationship with firm performance in Japan whereas a negative relationship is found in Sri Lanka. In sum, finding supports that view of the extant studies that family ownership and firm performance have a curvilinear relationship meaning that ownership concentration beyond a certain point likely creates entrenchment and consequently negative effects on performance.
Mobile Health Services
Authors: Nisha Nabila , Iqbal Mehree , Rifat Afrin , Idrish Sherina
Published: April 2015

Today, information and communication technology (ICTs) are influencing health system development across many developing countries, particularly through the application of mobile communications. As such, there has been an initiation of a new paradigm of mobile health services which has made healthcare delivery more accessible, affordable and effective. However, such service delivery platform has been mainly targeted towards the rural population, so there is growing concerns about its acceptance and future use intentions in the urban areas. The aim of this paper is to examine and critically assess the underlying factors that can influence future use intentions of mHealth services in the context of Bangladesh. The conceptual model of the study identifies that information quality, facilitating conditions, trust and effort expectancy plays an important role in capturing users' overall perceptions of mobile health services. Finally, the study highlights the managerial implications, future research directions and limitations from the perspective of Bangladesh.
A Study on Performance Evaluation of Initial Public Offerings (IPOs) in India during 2007-13
Authors: Dokku Srinivasa Rao , Jampala Rajesh Choudary , Lakshmi P. Adi
Published: April 2015

The authors analyze 146 Indian Initial Public Offerings (IPOs) that were listed in Bombay Stock Exchange (BSE) between January 2007 and December 2009. The units of the sample are selected on the basis of companies available in the Indian stock market for three years for calculating short-term and long-term returns. The evidence suggests that the IPOs are initial day underpriced by 4.25 per cent and underperformed by 29.06 per cent after 36 months of listing. The study also finds that issue variables are highly influencing the IPOs performance in short run and long run but age of the company doesn't have any influence on its performance during the study period. The JEL classifications are G12, G14, G24, and G32.
Rule of Law
Authors: Anjinappa Gopala
Published: April 2015

The world as a whole has developed in the global dimension and has flourished with prosperity. But still one can see the hurdles in the development process. One of such impediments is poverty and the other is the environmental problems. Poverty results in violation of human rights. The rule of law is crucial and is one of the means to strengthen these hurdles. One of such escalation is on the environmental development wherein it strives for achieving sustainable development and eradication of poverty. The rule of law plays a vital role in reducing extreme poverty with emphasizing on human rights. It is the very essence and the core of Good Governance. Without the principles of the rule of law, it will not be enough to achieve sustainable development and eradication of poverty. The rule of law strengthens to provide intense legal framework. It works as an effective mechanism for the enforcement of law. Innovative methods are undertaken to aim in the enforcement of sustainable development and eradication of poverty. The paper implies on effectiveness of the rule of law in providing sustainable development policies. It analyses the legal framework in India that contributes in maintaining economic imbalances. The paper explores the role of Indian Judiciary and the classic Judgments of Supreme Court of India. Keeping in view the importance of sustainable development and eradication of poverty, the paper contributes to explore the significance of the rule of law in achieving the objective of the nation. “Development is one of the primary means of improving the environment for living, or providing food, water, sanitation and shelter, of making the deserts green and the mountains habitable” (Indira Gandhi, 1972).
Revealing Customer Behavior on Smartphones
Authors: Almunawar Mohammad Nabil , Anshari Muhammad , Susanto Heru , Chen Chin Kang
Published: April 2015

Recent development of mobile phones is very interesting as the new generation, known as “smart phones”, offer highly attractive features. The main advantage of smart phones is the ability to connect to the Internet from anywhere, consequently enabling them to remain continuously in touch with their social networks. This paper discusses how consumers in Brunei Darussalam (Brunei) responded to the survey of smart phones. A Theory of Reasoned Action Model is used to understand customers preference in choosing a specific product over the other. To assess the use of smart phones, the authors conducted surveys with consumers, stressing on product preferences, consumption behavior of smart phones, as well as opinions on the functionality of smart phones. The smart phone market in Brunei is dominated by the younger generation who is less sensitive towards price. In terms of usability, consumers prefer smart phones more than tablets or other mobile devices, the reason for their preference being the superior functional features which exist in smart phones.
Current Developing Trend of Sales Tax on E-Business
Authors: Yang James G. S. , Lohrey Peter L. , Lauricella Leonard J.
Published: April 2015

This article explores the development of sales tax on e-business. It points out that the problem was rooted in the fact that the seller is required to collect and remit the tax to the buyer's state government. If the seller and the buyer do not reside in the same state, the buyer's state government has no jurisdiction over the seller, unless there is a “physical presence” of the seller in the buyer's state. A state government can require an out-of-state seller to collect sales tax from the in-state buyer only when there is “physical presence.” However, what constitutes “physical presence” can become very controversial and complex. This article discusses many court cases. As Internet commerce was incorporated into the business operations, a great many transactions were executed online. The concept of “physical presence” became even more complex, as websites and digitized products became more commonplace. A new concept of “economic nexus” has evolved under many state statutes. Now an out-of-state seller may be required to collect sales tax from an in-state buyer, regardless of “physical presence.” In 2013 the United States Senate enacted the “Marketplace Fairness Act of 2013.” This embraced the concept of “economic nexus.” This legislation could potentially end or at least greatly simplify all controversies in e-business taxation. This paper further notes that the concept of “economic nexus” may be extended to the arena of state income tax.
Beliefs and Attributions toward Computing Technology
Authors: Johnson Richard D. , Veltri Natasha , Thatcher Jason B.
Published: April 2015

This study critiques and extends the work of , who investigated the relations between social cues in an interface, user personality, user beliefs about the social role and capabilities of computers, and the attributions of responsibility users made for their interactions and outcomes with a computer. In this study, rather than examining the simple, direct effects investigated previously, we examine the moderating role of social cues in the interface. In addition, building upon recent findings from psychology, the authors assess personality traits individually, rather than aggregating them. To evaluate the theorized relations, 152 individuals participated in a controlled laboratory experiment, where social cues in two computer interfaces were manipulated. Results indicate that social cues moderate the relations between personality, beliefs about the social role of computing, and the attributions made. In addition, the results suggest that disaggregating personality traits is theoretically and practically richer than aggregating them.
The effect of inclined position on stone free rates in patients with lower caliceal stones during SWL session
Authors: Cakiroglu Basri , Sinanoglu Orhun , Tas Tuncay , Hazar Ismet Aydin , Balci Mustafa Bahadir Can
Published: April 2015

Objective: To compare the outcomes of shock wave lithotripsy (SWL) combined with inclined position and SWL alone in patients with lower pole calyx stones. Methods: Seven hundred forty patients who underwent SWL treatment for lower pole renal stones with a total diameter of 2 cm or less were prospectively randomized into two groups. They were comparable in terms of age, sex, and stone diameters. Patients with lower calyceal stones (4-20 mm) were randomized to SWL (368 patients) or SWL with simultaneous inclination (372 patients) with 30o head down Trendelenburg position). Shock wave and session numbers were standardized according to stone size. Additional standardized shock waves were given to patients with stone fragments determined by kidney urinary bladder film and ultrasound at weeks 1, 4, 10. Results: The overall stone free rate (SFR) was 73% (268/368) in patients with SWL alone and 81% (300/372) in SWL with inclination at the end of 12th week (p = 0.015). No significant adverse events were noted in both treatment groups. Conclusion: Simultaneous inclination of patients during SWL session increase SFR in lower caliceal stones significantly compared to SWL treatment alone.
Evaluation of laparoscopic vs robotic partial nephrectomy using the margin, ischemia and complications score system: a retrospective single center analysis
Authors: Ricciardulli Stefano , Ding Qiang , Zhang Xu , Li Hongzhao , Tang Yuzhe , Yang Guoqiang , Wang Xiyou , Ma Xin , Breda Alberto , Celia Antonio
Published: April 2015

Objective: To evaluate differences between Laparoscopic Partial Nephrectomy (LPN) and Robot-Assisted Partial Nephrectomy (RAPN) using the Margin, Ischemia and Complications (MIC) score system and to evaluate factors related with MIC success. Materials and Methods: Single centre retrospective study on 258 LPN and 58 RAPN performed between January 2012 and January 2014. Success was defined when surgical margins was negative, Warm Ischemia Time (WIT) was ≤ 20 minutes and no major complications occurred. Mann-Whitney-U and Pearson χ2 correlation were used to compare LPN and RAPN. A matched pair comparison was also performed. Spearman correlation (Rho) was used to evaluate the relationship between clinical, intra and post-operative and pathological patients characteristics with MIC score. A binary regression analysis was also performed to evaluate independent factors associated with MIC success. Results: The MIC rate in LPN and RAPN was 55% and 65.5% respectively. No differences in clinical, intra and post-operative outcomes between groups were found. Clinical tumor size (p-value: < 0.001; OR: 0.829; 95% CI: 0.697-0.987), PADUA score (p-value: < 0.001; OR: 0.843; 95% CI: 0.740-0.960), PADUA risk groups (intermediate; p-value: < 0.001; OR: 0.416; 95% CI: 0.238- 0.792; high: p-value: < 0.001; OR: 0.356; 95% CI: 0.199- 0.636), WIT (p-value: < 0.001; OR: 0.598; 95% CI: 0.530- 0.675) were independently associated with MIC. eGFR (< 60 vs ≥ 60 ml/min per 1.73 m2: p-value: < 0.001; OR: 3.356; 95% CI: 1.701-6.621) and Fuhrman nuclear grade (p-value: 0.014; OR: 1.798; 95% CI:1.129-2.865) were also independently associated with MIC. Conclusions: MIC score system is a simple and useful tool to report and to compare different surgical approach.
Balancing life and medical school
Authors: Cisneros Victor , Goldberg Iliya , Schafenacker Amanda , Bota Robert G.
Published: April 2015

not required
Evolution of Surprise Rapids Landslide, Yukon Territory
Authors: Ward B C , Jackson L E , Savigny K W
Published: April 2015

The Surprise Rapids landslide is a complex of earthflows and debris flows covering an area of about 1.7 km2. This failure is the most extensive of its kind in central Yukon. The cause of the initial failure at the site is unknown. Subsequent growth involved
bimodal flows and reactivation of landslide colluvium. Debris flows and earthflows were extremely mobile traversing slopes as low as 3°. Landsliding likely began in the 1870s, after a forest fire had swept the site. The landslide involves seven geomorphic elements based upon chronological order
of major failure events. Earth and debris flow activity was greatest during the second, fourth, and seventh decades of this century. Landsliding has been coincident with post Little Ice Age climatic amelioration. Warmer summers, especially during the 1940s may have had a role in accelerating the
flow of the earth and debris.
Paleoseismology and seismic hazards, southwestern British Columbia
Authors: Clague J J
Published: April 2015

There have been nine magnitude 6-7 earthquakes in southwestern British Columbia and northwestern Washington State since the late 1800s, and geological evidence indicates that even larger earthquakes, with no precedent in the historical period, have occurred in
the recent past. Holocene coastal stratigraphy on western Vancouver Island and in Washington State and Oregon records episodic sudden submergence during late Holocene time. The submergence is inferred to be the result of subsidence during great (M8-9) earthquakes on the nearby Cascadia subduction
zone. These earthquakes have occurred, on average, once every several hundred years during the late Holocene, most recently about 300 years ago. They were accompanied by large tsunamis that deposited distinctive sheets of sand and gravel in low-lying coastal areas. Abrupt changes in vegetation and
sedimentation in coastal wetlands near Vancouver and Victoria about 3600 and 1900 years ago record large earthquakes centred on the Cascadia subduction zone or within the North America or Juan de Fuca plate. Ground shaking during the 1900-year-old earthquake and possibly during younger seismic
events generated sand and silt dykes and "blows" on the Fraser River delta and along Serpentine River south of Vancouver.

Seismic hazards include ground motion, ground rupture, coseismic subsidence and flooding, tsunamis and seiches, liquefaction, and landsliding. Seismic shaking may directly damage buildings and other structures, and induce destructive secondary phenomena such as liquefaction, landsliding, and fire.
Large tsunamis can be triggered by earthquakes on the Cascadia subduction zone or by distant plate-boundary earthquakes elsewhere in the North Pacific Ocean, and are most likely to damage coastal communities on western Vancouver Island.

Although an M8-9 subduction earthquake would affect a much larger area than an M6-7 crustal or subcrustal event, its probability of occurrence is about 50 times less. Furthermore, recent earthquakes at Los Angeles (1994, M6.7, U.S. $26 billion damage) and near San Francisco (1989, M7.2, U.S. $10
billion) show how destructive earthquakes of the same size as those that occur regularly in the Pacific Northwest can be. In view of this, a greater effort should be made to better understand the causes of moderate and large earthquakes within the North America and Juan de Fuca
plates.
Diurnal and Row Effects on Paddy Rice Backscatter
Authors: Ross S , Brisco B , Brown R J , Yun S
Published: April 2015

Rice is a very important crop providing not only a staple in the daily food requirements of many people but also an important source of income for rice exporting countries such as Thailand and Vietnam. Due to the prevalence of cloud cover in important rice
producing regions, radar remote sensing provides an attractive source of data for mapping and monitoring objectives. This paper addresses the use of RADARSAT for mapping and monitoring paddy rice. The underlying water surface in paddy rice production systems enhances the radar backscatter from the
rice plants such that identification and monitoring appears very promising. Due to the desire to use both ascending and descending orbits for this temporally dynamic monitoring application, the effect of time of day and look direction was evaluated in this study. The results show that at some times
data from different orbits can be used without correction for diurnal plant moisture changes or azimuth look direction effects, but in other cases row direction influences or time of day effects may be significant. This has implications on developing RADARSAT data acquisition scenarios for
monitoring paddy rice. Additional work is required to determine the magnitude of change over a growing season, as a function of incidence angle, to fully evaluate this effect.
Altered Sirtuin 7 Expression is Associated with Early Stage Breast Cancer
Authors: Aljada Ahmad , Saleh Ayman M. , Alkathiri Moath , Shamsa Heba Bani , Al-Bawab Ahmad , Nasr Amre
Published: April 2015

Background

To evaluate sirtuin-7 (SirT7) mRNA expression status in breast cancer patients with different metastatic stages and survey SirT7 mRNA expression status in eight different types of cancer.

Methods

The expression of SirT7 in the commercially available TissueScan qPCR Breast Cancer Disease cDNA arrays containing 16 normal, 23 Stage I, 36 IIA, 22 IIB, 8 IIIA, 23 IIIA, 6 IIIB, 13 IIIC, and 5 IV were evaluated by quantitative real-time polymerase chain reaction (qRT-PCR) assay. Similar analysis was performed in TissueScan qPCR Cancer Survey cDNA array, which includes breast, colon, kidney, liver, lung, ovarian, prostate, and thyroid specimens.

Results

The mRNA expression levels of SirT7 were significantly higher in breast cancer samples compared to normal breast specimens ( P < 0.001). Stratification of patients into groups according to metastatic stages indicated statistically significantly higher levels of SirT7 mRNA in CS-I, CS-II, and CS-III when compared to normal breast tissue ( P < 0.05). Notably, SirT7 mRNA levels were higher in CS-I, CS-IIA, CS-IIB, and CS-IIIA ( P < 0.05). Additionally, there were significantly lower SirT7 mRNA levels in thyroid carcinoma when compared to their corresponding normal tissue ( P < 0.05).

Conclusions

Our results indicate an increase in the mRNA expression level of SirT7 in breast cancer, particularly in CS-I, CS-IIA, CS-IIB, and CS-IIIA. The relationship of altered SirT7 with breast cancer progression and patient survival should be prospectively explored in future studies.
Revisiting Twomey's approximation for peak supersaturation
Authors: Shipway B. J.
Published: April 2015

Abstract. Twomey's seminal 1959 paper provided lower and upper bound approximations to the estimation of peak supersaturation within an updraft and thus provides the first closed expression for the number of nucleated cloud droplets. The form of this approximation is simple, but provides a surprisingly good estimate and has subsequently been employed in more sophisticated treatments of nucleation parametrization. In the current paper, we revisit the lower bound approximation of Twomey and make a small adjustment that can be used to obtain a more accurate calculation of peak supersaturation under all potential aerosol loadings and thermodynamic conditions. In order to make full use of this improved approximation, the underlying integro-differential equation for supersaturation evolution and the condition for calculating peak supersaturation are examined. A simple rearrangement of the algebra allows for an expression to be written down that can then be solved with a single lookup table with only one independent variable for an underlying lognormal aerosol population. While multimodal aerosol with N different dispersion characteristics requires 2N+1 inputs to calculate the activation fraction, only N of these one-dimensional lookup tables are needed. No additional information is required in the lookup table to deal with additional chemical, physical or thermodynamic properties. The resulting implementation provides a relatively simple, yet computationally cheap, physically based parametrization of droplet nucleation for use in climate and Numerical Weather Prediction models.
Late Pleistocene–Holocene ground surface heat flux changes reconstructed from borehole temperature data (the Urals, Russia)
Authors: Demezhko D. Y. , Gornostaeva A. A.
Published: April 2015

Abstract. We use geothermal reconstruction of the ground surface temperature (GST) history early obtained in the Middle Urals to determine the surface heat flux (SHF) history over the past 35 kyr. A new algorithm of GST–SHF transformation was applied to solve this problem. The timescale of geothermal reconstructions has been corrected by comparing the estimated heat flux and annual insolation at the latitude of 60° N. The consistency of SHF and insolation changes on the interval 35–6 kyr BP with the linear correlation coefficient R = 0.99 points to orbital factors as the main cause of climatic changes during the Pleistocene–Holocene transition. The amplitude of SHF variations is about 1.3% of the insolation change amplitude. The increase of carbon dioxide concentrations lagged by 2–3 kyr from the SHF increase and occurred synchronously with GST changes.
CAMERA CONSTANT IN THE CASE OF TWO MEDIA PHOTOGRAMMETRY
Authors: Agrafiotis P. , Georgopoulos A.
Published: April 2015

Abstract. Refraction is the main cause of geometric distortions in the case of two media photogrammetry. However, this effect cannot be compensated and corrected by a suitable camera calibration procedure (Georgopoulos and Agrafiotis, 2012). In addition, according to the literature (Lavest et al. 2000), when the camera is underwater, the effective focal length is approximately equal to that in the air multiplied by the refractive index of water. This ratio depends on the composition of the water (salinity, temperature, etc.) and usually ranges from 1.10 to 1.34. It seems, that in two media photogrammetry, the 1.33 factor used for clean water in underwater cases does not apply and the most probable relation of the effective camera constant to the one in air is depending of the percentages of air and water within the total camera-to-object distance. This paper examines this relation in detail, verifies it and develops it through the application of calibration methods using different test fields. In addition the current methodologies for underwater and two-media calibration are mentioned and the problem of two-media calibration is described and analysed.
PILOT APPLICATION OF 3D UNDERWATER IMAGING TECHNIQUES FOR MAPPING POSIDONIA OCEANICA (L.) DELILE MEADOWS
Authors: Rende F. S. , Irving A. D. , Lagudi A. , Bruno F. , Scalise S. , Cappa P. , Montefalcone M. , Bacci T. , Penna M. , Trabucco B. , Di Mento R. , Cicero A. M.
Published: April 2015

Abstract. Seagrass communities are considered one of the most productive and complex marine ecosystems. Seagrasses belong to a small group of 66 species that can form extensive meadows in all coastal areas of our planet. Posidonia oceanica beds are the most characteristic ecosystem of the Mediterranean Sea, and should be constantly monitored, preserved and maintained, as specified by EU Habitats Directive for priority habitats. Underwater 3D imaging by means of still or video cameras can allow a detailed analysis of the temporal evolution of these meadows, but also of the seafloor morphology and integrity. Video-photographic devices and open source software for acquiring and managing 3D optical data rapidly became more and more effective and economically viable, making underwater 3D mapping an easier task to carry out. 3D reconstruction of the underwater scene can be obtained with photogrammetric techniques that require just one or more digital cameras, also in stereo configuration. In this work we present the preliminary results of a pilot 3D mapping project applied to the P. oceanica meadow in the Marine Protected Area of Capo Rizzuto (KR, Calabria Region – Italy).
BLIND DECONVOLUTION ON UNDERWATER IMAGES FOR GAS BUBBLE MEASUREMENT
Authors: Zelenka C. , Koch R.
Published: April 2015

Abstract. Marine gas seeps, such as in the Panarea area near Sicily (McGinnis et al., 2011), emit large amounts of methane and carbon-dioxide, greenhouse gases. Better understanding their impact on the climate and the marine environment requires precise measurements of the gas flux. Camera based bubble measurement systems suffer from defocus blur caused by a combination of small depth of field, insufficient lighting and from motion blur due to rapid bubble movement. These adverse conditions are typical for open sea underwater bubble images. As a consequence so called ’bubble boxes’ have been built, which use elaborate setups, specialized cameras and high power illumination. A typical value of light power used is 1000W (Leifer et al., 2003). In this paper we propose the compensation of defocus and motion blur in underwater images by using blind deconvolution techniques. The quality of the images can be greatly improved, which will relax requirements on bubble boxes, reduce their energy consumption and widen their usability.
3D MODELING OF THE ARCHAIC AMPHORAS OF IONIA
Authors: Denker A. , Oniz H.
Published: April 2015

Abstract. Few other regions offer such a rich collection of amphoras than the cities of Ionia. Throughout history amphoras of these cities had been spread all over the Mediterranean. Despite their common characteristics, amphora manufacturing cities of Ionia had their own distinctive styles that can be identified. They differed in details of shape and decoration. Each city produced an authentic type of amphora which served as a trademark of itself and enabled its attribution to where it originated from. That’s why, amphoras provide important insight into commerce of old ages and yield evidence into ancient sailing routes. Owing to this our knowledge of the ancient trade is profoundly enriched. The following is based on the finds of amphoras which originated from the Ionian cities of Chios, Clazomenai, Lesbos, Miletus, and Samos. Starting from city-specific forms which offer interpretative advantages in provenancing, this article surveys the salient features of the regional forms and styles of the those Ionian cities. 3D modeling is utilized with the aim of bringing fresh glimpses of the investigated amphoras by showing how they originally looked. Due to their virtual indestructibility these models offer interpretative advantages by enabling experimental testing of hypotheses upon the finds without risking them. The 3D models in the following sections were reconstructed from numerous fragments of necks, handles, body sherds and bases. They convey in color- unlike the monochrome drawings which we were accustomed to-the texture, decoration, tint and the vitality of the amphoras of Ionia.
Investigating microbial transformations of soil organic matter: synthesizing knowledge from disparate fields to guide new experimentation
Authors: Billings S. A. , Tiemann L. K. , Ballantyne IV F. , Lehmeier C. A. , Min K.
Published: April 2015

Abstract. Discerning why some soil organic matter (SOM) leaves soil profiles relatively quickly while other compounds, especially at depth, can be retained for decades to millennia is challenging for a multitude of reasons. Simultaneous with soil-specific advances, multiple other disciplines have enhanced their knowledge bases in ways potentially useful for future investigations of SOM decay. In this article, we highlight observations highly relevant for those investigating SOM decay and retention but often emanating from disparate fields and residing in literature seldom cited in SOM research. We focus on recent work in two key areas. First, we turn to experimental approaches using natural and artificial aquatic environments to investigate patterns of microbially mediated OM transformations as environmental conditions change, and highlight how aquatic microbial responses to environmental change can reveal processes likely important to OM decay and retention in soils. Second, we emphasize the importance of establishing intrinsic patterns of decay kinetics for purified substrates commonly found in soils to develop baseline rates. These decay kinetics – which represent the upper limit of the reaction rates – can then be compared to substrate decay kinetics observed in natural samples, which integrate intrinsic decay reaction rates and edaphic factors essential to the site under study but absent in purified systems. That comparison permits the site-specific factors to be parsed from the fundamental decay kinetics, an important advance in our understanding of SOM decay (and thus persistence) in natural systems. We then suggest ways in which empirical observations from aquatic systems and purified substrate–enzyme reaction kinetics can be used to advance recent theoretical efforts in SOM-focused research. Finally, we suggest how the observations in aquatic and purified substrate–enzyme systems could be used to help unravel the puzzles presented by oft-observed patterns of SOM characteristics with depth, as one example of the many perplexing SOM-related problems.
On producing sea ice deformation data sets from SAR-derived sea ice motion
Authors: Bouillon S. , Rampal P.
Published: April 2015

Abstract. We propose a method to reduce the error generated when computing sea ice deformation fields from synthetic aperture radar (SAR)-derived sea ice motion. The method is based on two steps. The first step consists of using a triangulation of the positions taken from the sea ice trajectories to define a mesh on which a first estimate of sea ice deformation is computed. The second step consists of applying a specific smoother to the deformation field to reduce the artificial noise that arises along discontinuities in the sea ice motion field. This method is here applied to RADARSAT Geophysical Processor System (RGPS) sea ice trajectories having a temporal and spatial resolution of about 3 days and 10 km, respectively. From the comparison between unfiltered and filtered fields, we estimate that the artificial noise causes an overestimation of about 60% of opening and closing. The artificial noise also has a strong impact on the statistical distribution of the deformation and on the scaling exponents estimated with multifractal analysis. We also show that a similar noise is present in the deformation fields provided in the widely used four-point deformation RGPS data set. These findings may have serious implications for previous studies as the constant overestimation of the opening and closing could lead to a large overestimation of freezing in leads, salt rejection and sea ice ridging.
Simulated high-latitude soil thermal dynamics during the past four decades
Authors: Peng S. , Ciais P. , Krinner G. , Wang T. , Gouttevin I. , McGuire A. D. , Lawrence D. , Burke E. , Chen X. , Delire C. , Koven C. , MacDougall A. , Rinke A. , Saito K. , Zhang W. , Alkama R. , Bohn T. J. , Decharme B. , Hajima T. , Ji D. , Lettenmaier D. P. , Miller P. A. , Moore J. C. , Smith B. , Sueyoshi T.
Published: April 2015

Abstract. Soil temperature (Ts) change is a key indicator of the dynamics of permafrost. On seasonal and inter-annual time scales, the variability of Ts determines the active layer depth, which regulates hydrological soil properties and biogeochemical processes. On the multi-decadal scale, increasing Ts not only drives permafrost thaw/retreat, but can also trigger and accelerate the decomposition of soil organic carbon. The magnitude of permafrost carbon feedbacks is thus closely linked to the rate of change of soil thermal regimes. In this study, we used nine process-based ecosystem models with permafrost processes, all forced by different observation-based climate forcing during the period 1960–2000, to characterize the warming rate of Ts in permafrost regions. There is a large spread of Ts trends at 20 cm depth across the models, with trend values ranging from 0.010 ± 0.003 to 0.031 ± 0.005 °C yr−1. Most models show smaller increase in Ts with increasing depth. Air temperature (Ta) and longwave downward radiation (LWDR) are the main drivers of Ts trends, but their relative contributions differ amongst the models. Different trends of LWDR used in the forcing of models can explain 61% of their differences in Ts trends, while trends of Ta only explain 5% of the differences in Ts trends. Uncertain climate forcing contributes a larger uncertainty in Ts trends (0.021 ± 0.008 °C yr−1, mean ± SD) than the uncertainty of model structure (0.012 ± 0.001 °C yr−1), diagnosed from the range of response between different models, normalized to the same forcing. In addition, the loss rate of near-surface permafrost area, defined as total area where the maximum seasonal active layer thickness (ALT) is less than 3 m loss rate is found to be significantly correlated with the magnitude of the trends of Ts at 1 m depth across the models (R = −0.85, P = 0.003), but not with the initial total near-surface permafrost area (R = −0.30, P = 0.438). The sensitivity of the total boreal near-surface permafrost area to Ts at 1 m, is estimated to be of −2.80 ± 0.67 million km2 °C−1. Finally, by using two long-term LWDR datasets and relationships between trends of LWDR and Ts across models, we infer an observation-constrained total boreal near-surface permafrost area decrease comprised between 39 ± 14 × 103 and 75 ± 14 × 103 km2 yr−1 from 1960 to 2000. This corresponds to 9–18% degradation of the current permafrost area.
Bone Marrow Mesenchymal Stem Cell Transplantation Retards the Natural Senescence of Rat Hearts
Authors: Zhang Mingyu , Liu Di , Li Shuang , Chang Lingling , Zhang Yu , Liu Ruixue , Sun Fei , Duan Wenqi , Du Weijie , Wu Yanping , Zhao Tianyang , Xu Chaoqian , Lu Yanjie
Published: April 2015

Bone marrow mesenchymal stem cells (BMSCs) have been shown to offer a wide variety of cellular functions including the protective effects on damaged hearts. Here we investigated the antiaging properties of BMSCs and the underlying mechanism in a cellular model of cardiomyocyte senescence and a rat model of aging hearts. Neonatal rat ventricular cells (NRVCs) and BMSCs were cocultured in the same dish with a semipermeable membrane to separate the two populations. Monocultured NRVCs displayed the senescence-associated phenotypes, characterized by an increase in the number of β-galactosidase-positive cells and decreases in the degradation and disappearance of cellular organelles in a time-dependent manner. The levels of reactive oxygen species and malondialdehyde were elevated, whereas the activities of antioxidant enzymes superoxide dismutase and glutathione peroxidase were decreased, along with upregulation of p53, p21Cip1/Waf1, and p16INK4a in the aging cardiomyocytes. These deleterious alterations were abrogated in aging NRVCs cocultured with BMSCs. Qualitatively, the same senescent phenotypes were consistently observed in aging rat hearts. Notably, BMSC transplantation significantly prevented these detrimental alterations and improved the impaired cardiac function in the aging rats. In summary, BMSCs possess strong antisenescence action on the aging NRVCs and hearts and can improve cardiac function after transplantation in aging rats. The present study, therefore, provides an alternative approach for the treatment of heart failure in the elderly population.

Significance

This study demonstrates that bone marrow mesenchymal stem cells show antisenescence action on aging neonatal rat ventricular cells and heart and improve cardiac function in aging rats. The results provide a novel strategy for retarding the cardiac aging process in physiology and abnormal conditions or pathology. This study also provides an alternative approach for treatment of heart failure in the elderly population.
Eimeria rangiferis (Protozoa: Eimeriidae) reported from caribou in Ameralik, West Greenland
Authors: Skírnisson Karl , Cuyler Christine
Published: April 2015

In recent decades the native Barren-ground caribou (Rangifer tarandus groenlandicus) south of the Godthaabs fjord (Nuup Kangerlua fjord) in West Greenland have mixed with semi-domesticated Norwegian reindeer (R. t. tarandus) imported in 1952 from Finnmark Norway and released onto the range of the Ameralik caribou population. Fecal samples from three calves of the Ameralik caribou population were examined for the presence of nematode eggs and eimerid oocysts. Two distinct nematode egg types were observed: the first, Nematodirella longissimespiculata, was found in all calves, while the second, a strongylid nematode, was detected in one calf. The coccidian eimerid Eimeria rangiferis was identified in all calves. This host-specific eimerid is found in Icelandic feral reindeer, which were also imported from Finnmark Norway. We suggest that Finnmark reindeer were the source of Eimeria rangiferis observed in Ameralik caribou today. There are three possible origins for the presence of N. longissimespiculata in Ameralik, 1) arrival with colonizing caribou from North America within the past 4000 years, 2) the 1952 introduction of semi-domesticated Norwegian reindeer, or 3) the current immigration of muskoxen.
Variability in the origins and pathways of Pacific Equatorial Undercurrent water
Authors: Qin Xuerong , Sen Gupta Alex , van Sebille Erik
Published: April 2015

The Pacific Equatorial Undercurrent (EUC) transports water originating from a number of distinct source regions, eastward across the Pacific Ocean. It is responsible for supplying nutrients to the productive eastern Equatorial Pacific Ocean. Of particular importance is the transport of iron by the EUC; the limiting nutrient in that region. Although the mean circulation and sources of EUC water are reasonably well understood, it is unclear how the contribution of water from these sources to the EUC vary on seasonal to interannual timescales. Here a Lagrangian analysis is applied to the eddy‐resolving OFAM3 ocean simulation in order to identity variability in the makeup of the EUC over an 18 year period (1993–2010). While ENSO has an influence on the variability of source transport contributions to the EUC, the signal of increased (decreased) transport of water from the LLWBCs during El Niño (La Niña) periods does not translate to substantial changes in the makeup of the EUC between 165°E and 140°W. It is hypothesized that this is due to the large spread in travel times of water parcels as they travel from the source regions into the EUC. The consequent erosion of transport anomalies generated at the different western boundary source regions associated with ENSO may help explain why previous studies found little relationship between variability in iron fluxes off Papua New Guinea shelves and the chlorophyll response in the eastern tropical Pacific.
Internal tides and associated vertical mixing in the Indonesian Archipelago
Authors: Nagai Taira , Hibiya Toshiyuki
Published: April 2015

Tidal mixing in the Indonesian Archipelago contributes to regulation of the tropical atmospheric circulation and water‐mass transformation in the Indonesian Throughflow. The present study quantifies the vertical diffusivity in the Indonesian Archipelago by driving a high‐resolution three‐dimensional numerical model and investigates the processes of internal tide generation, propagation, and dissipation. The numerical experiment shows that
internal tides are effectively generated over prominent subsurface ridges. The conversion rate from
barotropic to baroclinic energy over the whole analyzed model domain is estimated to be 85.5 GW. The generated internal tides dissipate 50–100% of their energy in close proximity to the generation sites (“near‐field”), and the remaining baroclinic energy propagates away causing relatively large energy dissipation far from the generation sites (“far‐field”). The local dissipation efficiency q, therefore, has an extremely nonuniform spatial distribution, although it has been assumed to be constant in the existing tidal mixing parameterization for the Indonesian Archipelago. Compared with the model‐predicted values, the existing parameterization yields the same order of vertical diffusivity averaged within the Indonesian Archipelago, but significantly overestimated (or underestimated) vertical diffusivity in the near‐field (or the far‐field). This discrepancy is attributable to the fact that the effects of internal wave propagation are completely omitted in the existing parameterization, suggesting the potential danger of using such parameterized vertical mixing in predicting the distribution of SST as well as water‐mass transformation in the Indonesian Seas.
Holey Graphene Nanomanufacturing: Structure, Composition, and Electrochemical Properties
Authors: Lin Yi , Han Xiaogang , Campbell Caroline J. , Kim Jae‐Woo , Zhao Bin , Luo Wei , Dai Jiaqi , Hu Liangbing , Connell John W.
Published: April 2015

Topology is critical for properties and function of 2D nanomaterials. Membranes and films from 2D nanomaterials usually suffer from large tortuosity as a result from dense restacking of the nanosheets and thus have limited utility in applications such as electrodes for supercapacitor and batteries, which require ion transport through the nanosheet thickness. In comparison with conventional porous 2D nanomaterials, introducing holes through the nanosheets to create holey 2D nanomaterials with retention of the 2D‐related properties is a more viable approach to improve molecular transport. Here, graphene is used as a model to study the fundamental structure‐property relationship as a result from defect‐enabled hole creation. Specifically, the correlation of electrochemical capacitive properties with structure and composition for holey graphene materials is prepared using a highly scalable controlled air oxidation process. The presence of holes on graphene sheets is not sufficient to account for the observed capacitance improvement. Rather, the improvement is achieved through the combination of an enhanced mesopore fraction with simultaneous oxygen doping while retaining the graphitic carbon network with minimal damage. The detailed understanding might be further applied to other 2D materials toward a broader range of both energy‐related and other applications.
Experimental studies and modeling of CO2 solubility in high temperature aqueous CaCl2, MgCl2, Na2SO4, and KCl solutions
Authors: Zhao Haining , Dilmore Robert M. , Lvov Serguei N.
Published: April 2015

The phase equilibria of CO2 and aqueous electrolyte solutions are important to various chemical‐, petroleum‐, and environmental‐related technical applications. CO2 solubility in aqueous CaCl2, MgCl2, Na2SO4, and KCl solutions at a pressure of 15 MPa, the temperatures from 323 to 423 K, and the ionic strength from 1 to 6 mol kg−1 were measured. Based on the measured experimental CO2 solubility, the previous developed fugacity‐activity thermodynamic model for the CO2‐NaCl‐H2O system was extended to account for the effects of different salt species on CO2 solubility in aqueous solutions at temperatures up to 523 K, pressures up to 150 MPa, and salt concentrations up to saturation. Comparisons of different models against literature data reveal a clear improvement of the proposed PSUCO2 model in predicting CO2 solubility in aqueous salt solutions. © 2015 American Institute of Chemical Engineers AIChE J, 61: 2286–2297, 2015
A generalized procedure for the prediction of multicomponent adsorption equilibria
Authors: Ladshaw Austin , Yiacoumi Sotira , Tsouris Costas
Published: April 2015

Prediction of multicomponent adsorption equilibria has been investigated for several decades. While there are theories available to predict the adsorption behavior of ideal mixtures, there are few purely predictive theories to account for nonidealities in real systems. Most models available for dealing with nonidealities contain interaction parameters that must be obtained through correlation with binary‐mixture data. However, as the number of components in a system grows, the number of parameters needed to be obtained increases exponentially. Here, a generalized procedure is proposed, as an extension of the predictive real adsorbed solution theory, for determining the parameters of any activity model, for any number of components, without correlation. This procedure is then combined with the adsorbed solution theory to predict the adsorption behavior of mixtures. As this method can be applied to any isotherm model and any activity model, it is referred to as the generalized predictive adsorbed solution theory. © 2015 American Institute of Chemical Engineers AIChE J, 61: 2600–2610, 2015
Linearly Tunable Emission Colors Obtained from a Fluorescent–Phosphorescent Dual‐Emission Compound by Mechanical Stimuli
Authors: Mao Zhu , Yang Zhiyong , Mu Yingxiao , Zhang Yi , Wang Yi‐Fan , Chi Zhenguo , Lo Chang‐Cheng , Liu Siwei , Lien Alan , Xu Jiarui
Published: April 2015

Organic mechanoluminochromic materials are mechano/piezo‐responsive and promising for applications in sensors, displays, and data storage devices. However, their switching range of emission is seriously impeded by only one kind of emission (either a fluorescent or phosphorescent peak) in the spectrum of single organic compounds. This study presents a design strategy for pure organic compounds with excellent room‐temperature fluorescent–phosphorescent dual‐emission (rFPDE) properties, which combines the effective factors of dipenylsulfone group, crystalline state, and heavy atom effect. Following the principle of color mixing, myriad emission colors with a wide range from orange to purple and across white zone in a straight line in the chromaticity diagram of the Commission Internationale de l’Eclairage (CIE) can be obtained by simply mechanical grinding the compound. The unique properties could be concentrated on a pure organic compound through this design strategy, which provides a new efficient channel for the discovery of efficient mechano‐responsive organic materials.
Cross‐β Amyloid Nanohybrids Loaded With Cytochrome C Exhibit Superactivity in Organic Solvents
Authors: Kapil Nidhi , Singh Ashmeet , Das Dibyendu
Published: April 2015

The present study reports the development of a unique class of Cytochrome C (CytC)‐loaded cross‐beta amyloid nanohybrids. The peroxidase activity of the bound CytC increased up to two orders of magnitude in organic solvents compared to the activity of unbound CytC in water. The amyloid sequences used in the study feature the nucleating core 17LVFF21 of the beta amyloid (Aβ), which assembled to form homogenous fibers and nanotubes. The morphology and exposed surface of the amyloid nanohydrids critically modulated the CytC activity. A CytC–Ac‐KLVFFAE‐NH2 hybrid featuring nanofiber morphology showed 308‐fold higher activity than unbound CytC in water, which increased to 450‐fold with the nanotube morphology of CytC–Ac‐KLVFFAL‐NH2. Notably, activity declined substantially when the exposed surface charge was detuned by replacing lysine with histidine, thus underpinning the importance of surface charge. This enzyme–amyloid nanohybrid system could facilitate the technological application of enzymes.