bluuebunny/crossref_metadata_2025 huggingface dataset:
The high hydraulic conductivity of three wooded tropical peat swamps in northeast Peru: measurements and implications for hydrological function
Authors: Kelly Thomas J. , Baird Andy J. , Roucoux Katherine H. , Baker Timothy R. , Honorio Coronado Eurídice N. , Ríos Marcos , Lawson Ian T.
Published: May 2013

The form and functioning of peatlands depend strongly on their hydrological status, but there are few data available on the hydraulic properties of tropical peatlands. In particular, the saturated hydraulic conductivity (K) has not previously been measured in neotropical peatlands. Piezometer slug tests were used to measure K at two depths (50 and 90 cm) in three contrasting forested peatlands in the Peruvian Amazon: Quistococha, San Jorge and Buena Vista. Measured K at 50 cm depth varies between 0.00032 and 0.11 cm s−1, and at 90 cm, it varies between 0.00027 and 0.057 cm s−1. Measurements of K taken from different areas of Quistococha showed that spatial heterogeneity accounts for ~20% of the within‐site variance and that depth is a good predictor of K. However, K did not vary significantly with depth at Buena Vista and San Jorge. Statistical analysis showed that ~18% of the variance in the K data can be explained by between‐site differences. Simulations using a simple hydrological model suggest that the relatively high K values could lead to lowering of the water table by >10 cm within ~48 m of the peatland edge for domed peatlands, if subjected to a drought lasting 30 days. However, under current climatic conditions, even with high K, peatlands would be unable to shed the large amount of water entering the system via rainfall through subsurface flow alone. We conclude that most of the water leaves these peatlands via overland flow and/or evapotranspiration. Copyright © 2013 John Wiley & Sons, Ltd.
Adipose tissue‐derived mesenchymal stem cells as monocultures or cocultures with human umbilical vein endothelial cells: Performancein vitroand in rat cranial defects
Authors: Ma Jinling , Both Sanne K. , Ji Wei , Yang Fang , Prins Henk‐Jan , Helder Marco N. , Pan Juli , Cui Fu‐Zhai , Jansen John A. , van den Beucken Jeroen J. P.
Published: May 2013

The aim of this study was to compare the osteogenic capacity between human adipose tissue‐derived mesenchymal stem cells (AT‐MSCs) and their cocultures with human umbilical vein endothelial cells (HUVECs)in vitroand their biological performancein vivo. First, the optimal cell ratio in cocultures for osteogenic differentiation was determined by seeding AT‐MSCs and HUVECs in ratios varying from 100:0 to 0:100 on tissue culture plates. Afterward, AT‐MSCs and AT‐MSCs/HUVECs (50:50) were seeded on porous titanium fiber mesh scaffolds (Ti) for bothin vitroandin vivoosteogenic evaluation. Forin vitroevaluation, cell osteogenic differentiation was assessed by alkaline phosphatase (ALP) activity and calcium assay. Forin vivoevaluation, the scaffolds were implanted bilaterally into rat cranial defects (5 mm diameter) and bone formation was assessed histologically and histomorphometrically after 8 weeks. The ratio of 50:50 was chosen in the cocultures because this coculture condition retained similar amount of calcium deposition while using the least amount of AT‐MSCs. Moreover, AT‐MSCs showed higher osteogenic differentiation in comparison to AT‐MSCs/HUVECs on Tiin vitro. Furthermore, superior bone formation was observed in AT‐MSCs compared to AT‐MSCs/HUVECs in rat cranial defects. In conclusion, AT‐MSCs showed significantly higher osteogenic potential compared to AT‐MSCs/HUVECs bothin vitroandin vivo. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 1026–1036, 2014.
Evidence for a short period of hydrologic activity in Newton crater, Mars, near the Hesperian‐Amazonian transition
Authors: Parsons R. A. , Moore J. M. , Howard A. D.
Published: May 2013

Hesperian/Amazonian‐aged valleys and alluvial fans distributed in regional clusters throughout the southern middle‐ to low‐latitudes were formed during a period of fluvial runoff and erosion which acted over a smaller spatial and temporal scale than the older, “classical” Martian valley networks dated to the Noachian‐Hesperian boundary. In order to explore the potential sources of water which formed these younger valleys, we calculated the expected sediment transport and water discharge rates for a valley and alluvial fan located in Newton crater (40°S, −159°E) over a wide range of water‐filled channel depths and sediment grain sizes in order to constrain the formation timescale and required water volume. Depending on the depth of the water‐filled channel within the valley, the alluvial fan was likely emplaced over ∼0.1 to ∼10 years of fluvial activity involving between 1.8 and 5.7 km 3 of water. These results imply water runoff rates of between 1 and 10 cm/d over a typical 300 km2 drainage area. Possible processes for delivering water to these drainages include high obliquity snowpack melting via volcanism or impacts resulting in either scattered, local to regional melting events or a brief global warming event. An extended, perhaps episodic, period of fluvial activity lasting hundreds of years driven by insolation‐induced melting of high obliquity snowpacks is another possibility.
Ultrastructure investigation of the secondary insemination system of the gamasid mite Hattena cometis domrow (Acari: Anactinotrichida: Ameroseiidae)
Authors: Di Palma Antonella , Seeman Owen , Alberti Gerd
Published: May 2013

Many gamasid mites, mainly of the taxon Dermanyssina, possess a secondarily evolved insemination system that is generally described as occurring in two types, the laelapid and the phytoseiid‐type, which are structurally considerably different. Considering that Dermanyssina represent the most recent and most diverse group of gamasid mites, it was expected that a greater diversity of insemination system than reflected by the two types could be present and could give an idea of its evolution within the taxon. Here, the authors present a description of the fine‐structure of the female secondary insemination system in the dermanyssine mite Hattena cometis. The system consists of a pair of sperm induction pores (solenostomes) and short sperm access ducts (tubules) which end in a syncytium. The syncytial strands of both sides meet medially under the ovary s.str., where they form a spherical syncytial spermatheca. Mature sperm cells of a modified ribbon type were seen in the syncytial parts of the system. The insemination system of Hattena cometis is regarded as a modification of the laelapid type. However, it is much simpler than that of Varroa destructor, the only other gamasid mite with the laelapid type studied ultrastructurally until now, and shows also some structural differences (e.g., no presence of an unpaired sperm duct). Hence, the present study suggests that some intermediate types might be revealed in future ultrastructure studies representing steps in the evolution of the insemination system in the Dermanyssina. J. Morphol. 274:918–925, 2013. © 2013 Wiley Periodicals, Inc.
Analysis of quantitative magnetic resonance imaging and biomechanical parameters on human discs with different grades of degeneration
Authors: Antoniou John , Epure Laura M. , Michalek Arthur J. , Grant Michael P. , Iatridis James C. , Mwale Fackson
Published: May 2013

Purpose

To establish relationships between quantitative MRI (qMRI) and biomechanical parameters in order to help inform and interpret alterations of human intervertebral discs (IVD) with different grades of degeneration.

Materials and Methods

The properties of the nucleus pulposus (NP) and annulus fibrosus (AF) of each IVD of 10 lumbar spines (range, 32–77 years) were analyzed by qMRI (relaxation times T1 and T2, magnetization transfer ratio [MTR], and apparent diffusion coefficient [ADC]), and tested in confined compression and dynamic shear.

Results

T1 and T2 significantly decreased in both the NP and AF with increasing degeneration grades while the MTR increased significantly with grade 4. In contrast to the other qMRI parameters, the ADC had a tendency to decrease with increasing grade. Disc degeneration caused a decrease in the aggregate modulus, hydraulic permeability and shear modulus magnitude along with an increase in phase angle in the AF. In contrast, disc degeneration of NPs demonstrated decreases in shear modulus and phase angle.

Conclusion

Our studies indicate that qMRI can be used as a noninvasive diagnostic tool in the detection of IVD properties with the potential to help interpret and detect early, middle, and late stages of degeneration. QMRI of human IVD can therefore become a very important diagnostic assessment tool in determining the functional state of the disc. J. Magn. Reson. Imaging 2013;38:1402–1414. © 2013 Wiley Periodicals, Inc.
A comparison of noise models in a hybrid reference spectrum and principal components analysis algorithm for Raman spectroscopy
Authors: Van de Sompel Dominique , Garai Ellis , Zavaleta Cristina , Gambhir Sanjiv Sam
Published: May 2013

Raman spectroscopy exploits the Raman scattering effect to analyze chemical compounds with the use of laser light. Raman spectra are most commonly analyzed using the ordinary least squares (LS) method. However, LS is known to be sensitive to variability in the spectra of the analyte and background materials. In a previous paper, we addressed this problem by proposing a novel algorithm that models expected variations in the analyte as well as background signals. The method was called the hybrid LS and principal component analysis (HLP) algorithm and used an unweighted Gaussian distribution to model the noise in the measured spectra. In this paper, we show that the noise in fact follows a Poisson distribution and improve the noise model of our hybrid algorithm accordingly. We also approximate the Poisson noise model by a weighted Gaussian noise model, which enables the use of a more efficient solver algorithm. To reflect the generalization of the noise model, we from hereon call the method the hybrid reference spectrum and principal components analysis (HRP) algorithm. We compare the performance of LS and HRP with the unweighted Gaussian (HRP‐G), Poisson (HRP‐P), and weighted Gaussian (HRP‐WG) noise models. Our experiments use both simulated data and experimental data acquired from a serial dilution of Raman‐enhanced gold‐silica nanoparticles placed on an excised pig colon. When the only signal variability was zero‐mean random noise (as examined using simulated data), HRP‐P consistently outperformed HRP‐G and HRP‐WG, with the latter coming in as a close second. Note that in this scenario, LS and HRP‐G were equivalent. In the presence of random noise as well as variations in the mean component spectra, the three HRP algorithms significantly outperformed LS, but performed similarly among themselves. This indicates that, in the presence of significant variations in the mean component spectra, modeling such variations is more important than optimizing the noise model. It also suggests that for real data, HRP‐WG provides a desirable trade‐off between noise model accuracy and computational speed. Copyright © 2013 John Wiley & Sons, Ltd.
Top‐down HPLC–ESI‐MS characterization of rat gliadoralin A, a new member of the family of rat submandibular gland glutamine‐rich proteins and potential substrate of transglutaminase
Authors: Cabras Tiziana , Iavarone Federica , Pirolli Davide , Cristina De Rosa Maria , Vitali Alberto , Faa Gavino , Cordaro Massimo , Messana Irene , Ekström Jörgen , Castagnola Massimo
Published: May 2013

During HPLC–ESI‐MS/MS analysis of rat submandibular saliva secreted under isoprenaline stimulation, a protein with an experimental [M+H]1+ = 10 544.24 m/z was detected (17.5 ± 0.7 min). The MS/MS fragmentation pattern, manually investigated, allowed establishing an internal sequence in agreement with a DNA‐derived sequence of an unknown rat protein coded D3Z9M3 (Swiss‐Prot). To match the experimental MS/MS fragmentation pattern and protein mass with theoretical data, the removal from the N terminus of the signal peptide and from the C terminus of three amino acid (a.a.) residues (Arg‐Ala‐Val) and the cyclization of the N‐terminal glutamine in pyroglutamic had to be supposed, resulting in a mature protein of 90 a.a. HPLC–ESI‐MS/MS of the trypsin digest ensured 100% sequence coverage. For the high glutamine content (34/90 = 37.8%) we propose to name this protein rat gliadoralin A 1–90. Low amounts of five different isoforms were sporadically detected, which did not significantly change their relative amounts after stimulation. Gliadoralin A is substrate for transglutaminase‐2, having Lys 60 and different Gln residues as major determinants for enzyme recognition. In silico investigation of superior structures evidenced that a small part of the protein adopts an α‐helical fold, whereas large segments are unfolded, suggesting an unordered conformation.
A Dyadic Analysis of the Influence of Trauma Exposure and Posttraumatic Stress Disorder Severity on Intimate Partner Aggression
Authors: Wolf Erika J. , Harrington Kelly M. , Reardon Annemarie F. , Castillo Diane , Taft Casey T. , Miller Mark W.
Published: May 2013

This study used structural equation modeling to evaluate a mediation model of the relationship between trauma exposure, posttraumatic stress disorder (PTSD) symptoms, and perpetration of intimate partner physical and psychological aggression in trauma‐exposed veterans and their cohabitating spouses (n = 286 couples; 88% male veteran and female spouse, 80.8% White, non‐Hispanic). Dyadic data analyses were used to simultaneously evaluate actor and partner effects using the actor–partner interdependence model (Kashy & Kenny, 2000). The primary hypothesis was that PTSD would mediate the association between trauma exposure and intimate partner physical and psychological aggression with these effects evident both within and across members of a couple (i.e., actor and partner effects). The best‐fitting model included (a) equivalent actor and partner direct effects of trauma on veterans’ acts of psychological aggression (β = .17 to .20, p = .001), and (b) equivalent actor and partner indirect effects via PTSD on veterans’ acts of physical aggression (β = .08 to .10, p < .001). There were no direct or indirect effects predicting the spouses’ aggression. Results suggest it is important to consider the trauma histories and possible presence of PTSD in both partners as this may be a point of intervention when treating distressed couples.
Find and Irradiate — Lasers Used for Weed Control
Authors: Kaierle Stefan , Marx Christian , Rath Thomas , Hustedt Michael
Published: May 2013

Due to their outstanding properties, interest in lasers has increased greatly in precision agriculture as a potential tool for non‐chemical weed control. unwanted plants have a negative effect on crop growth, especially in close surroundings. Weed control based on mechanical (e.g. hoeing) or thermal (flaming) methods do not meet the precision requirements to preserve crop plants. An innovative combination of image processing and laser technology is promising.
Cerebral TOF angiography at 7T: Impact of B1+ shimming with a 16‐channel transceiver array
Authors: Schmitter Sebastian , Wu Xiaoping , Adriany Gregor , Auerbach Edward J. , Uğurbil Kâmil , Van de Moortele Pierre‐François
Published: May 2013

Purpose

Time‐of‐flight (TOF) MR imaging is clinically among the most common cerebral noncontrast enhanced MR angiography techniques allowing for high spatial resolution. As shown by several groups TOF contrast significantly improves at ultrahigh field of B0 = 7T, however, spatially varying transmit B1 (B1+) fields at 7T reduce TOF contrast uniformity, typically resulting in suboptimal contrast and reduced vessel conspicuity in the brain periphery.

Methods

Using a 16‐channel B1+ shimming system, we compare different dynamically applied B1+ phase shimming approaches on the radiofrequency excitation to improve contrast homogeneity for a (0.5 mm)3 resolution multislab TOF acquisition. In addition, B1+ shimming applied on the venous saturation pulse was investigated to improve venous suppression, subcutaneous fat signal reduction and enhanced background suppression originating from MT effect.

Results

B1+ excitation homogeneity was improved by a factor 2.2–2.6 on average depending on the shimming approach, compared to a standard CP‐like phase setting, leading to improved vessel conspicuity particularly in the periphery. Stronger saturation, higher fat suppression and improved background suppression were observed when dynamically applying B1+ shimming on the venous saturation pulse.

Conclusion

B1+ shimming can significantly improve high resolution TOF vascular investigations at ultrahigh field, holding strong promise for non contrast‐enhanced clinical applications. Magn Reson Med 71:966–977, 2014. © 2013 Wiley Periodicals, Inc.
Detection of in vivo enzyme activity with CatalyCEST MRI
Authors: Yoo Byunghee , Sheth Vipul R. , Howison Christine M. , Douglas Matthew J. K. , Pineda Carlos T. , Maine Erin A. , Baker Amanda F. , Pagel Mark D.
Published: May 2013

Purpose

CatalyCEST MRI compares the detection of an enzyme‐responsive chemical exchange saturation transfer (CEST) agent with the detection of an unresponsive “control” CEST agent that accounts for other conditions that influence CEST. The purpose of this study was to investigate the feasibility of in vivo catalyCEST MRI.

Methods

CEST agents that were responsive and unresponsive to the activity of urokinase plasminogen activator were shown to have negligible interaction with each other. A CEST‐fast imaging with steady state precession (FISP) MRI protocol was used to acquire MR CEST spectroscopic images with a Capan‐2 pancreatic tumor model after intravenous injection of the CEST agents. A function of (super)‐Lorentzian line shapes was fit to CEST spectra of a region‐of‐interest that represented the tumor.

Results

The CEST effects from each agent showed the same initial uptake into tumor tissues, indicating that both agents had the same pharmacokinetic transport rates. Starting 5 min after injection, CEST from the enzyme‐responsive agent disappeared more quickly than CEST from the unresponsive agent, indicating that the enzyme responsive agent was being catalyzed by urokinase plasminogen activator, while both agents also experienced net pharmacokinetic washout from the tumor.

Conclusion

CatalyCEST MRI demonstrates that dynamic tracking of enzyme‐responsive and unresponsive CEST agents during the same in vivo MRI study is feasible. Magn Reson Med 71:1221–1230, 2014. © 2013 Wiley Periodicals, Inc.
A differential pattern of gene expression in skeletal muscle of tumor‐bearing rats reveals dysregulation of excitation–contraction coupling together with additional muscle alterations
Authors: Fontes‐Oliveira Cibely Cristine , Busquets Sílvia , Fuster Gemma , Ametller Elisabet , Figueras Maite , Olivan Mireia , Toledo Míriam , López‐Soriano Francisco J. , Qu Xiaoyan , Demuth Jeffrey , Stevens Paula , Varbanov Alex , Wang Feng , Isfort Robert J. , Argilés Josep M.
Published: May 2013

Introduction: Cachexia is a wasting condition that manifests in several types of cancer. The main characteristic of this condition is a profound loss of muscle mass. Methods: By using a microarray system, expression of several hundred genes was screened in skeletal muscle of rats bearing a cachexia‐inducing tumor, the AH‐130 Yoshida ascites hepatoma. This model induced a strong decrease in muscle mass in the tumor‐bearing animals, as compared with their healthy counterparts. Results: The results show important differences in gene expression in EDL skeletal muscle between tumor‐bearing animals with cachexia and control animals. Conclusions: The differences observed pertain to genes related to intracellular calcium homeostasis and genes involved in the control of mitochondrial oxidative phosphorylation and protein turnover, both at the level of protein synthesis and proteolysis. Assessment of these differences may be a useful tool for the design of novel therapeutic strategies to fight this devastating syndrome. Muscle Nerve 49: 233–248, 2014
Muscle‐related differences in mechanomyography–force relationships are model‐dependent
Authors: Cooper Michael A. , Herda Trent J.
Published: May 2013

Introduction: In this study we examined the mechanomyographic amplitude (MMGRMS)–force relationships with log‐transform and polynomial regression models for the vastus lateralis (VL), rectus femoris (RF), and first dorsal interosseous (FDI) muscles. Methods: Twelve healthy (age 23 ± 3 years) men performed isometric ramp contractions of the leg extensors and index finger from 10% to 80% of their maximal voluntary contraction (MVC) with MMG sensors positioned on the VL, RF, and FDI. Log‐transform and polynomial regression models were fitted to the relationships. Results: There were differences for the a terms (intercepts) and b terms (slopes) from the log‐transform model between the FDI, VL, and RF; however, there were no consistent differences identified with the polynomial regression models. Conclusions: The log‐transform model quantified differences in the patterns of responses between the FDI and the leg extensors, but polynomial regression could not distinguish such differences. Muscle Nerve 49: 202–208, 2014
Homogenization of anisotropic elastoplastic behaviors of a porous polycrystal with interface effects
Authors: He Z. , Caratini G. , Dormieux L. , Kondo D.
Published: May 2013

This paper is devoted to develop a theoretical framework to predict the macroscopic transversely isotropic elastoplastic behavior of clay‐like material, which is viewed as a porous polycrystal. We consider evolutions of two local plastic mechanisms of grains and interface simultaneously, for which a Schmid criterion is used for the strength of sheet‐like grains and a Tresca criterion for the strength of interfaces between particles. By adapting the standard incremental method, we propose firstly a classic self‐consistent model, which does not consider the effect of interface, then a generalized self‐consistent model in which the solid phase is represented by laminated (or isotropic) spherical grains surrounded by interfaces. Comparisons of numerical predictions between these two methods are performed and have demonstrated the validity of the generalized self‐consistent model taking account of interface effects. Numerical simulations of uniaxial compression tests have shown that the macroscopic elastoplastic behavior of polycrystalline (clay‐like) material can be successfully predicted by the way of considering the two local plastic mechanisms at microscopic scale. Copyright © 2013 John Wiley & Sons, Ltd.
Effective mechanical properties of polyvinylalcohol biocomposites with reinforcement of date palm leaf fibers
Authors: Mohanty Jyoti R. , Das Sankar N. , Das Harish C. , Swain Sarat K
Published: May 2013

Polyvinylalcohol/date palm leaf fiber (PVA/DPL) biocomposites were prepared by the melt mixing fabrication technique with various proportions of fibers. DPL fibers were chemically modified with the purpose of improving the dispersion and better compatibility with PVA matrix. Different chemical processes of modification were adopted and the tensile strengths of both treated and untreated fibers were compared. It was noticed that the tensile strength of acrylic acid treated fiber was optimum in comparison to other methods. The interaction of DPL fibers with PVA matrix were studied by Fourier transforms infrared spectroscopy (FTIR). Field emission scanning electron microscope (FESEM) was used to study the morphology of biocomposites. The tensile strength, Young's modulus, elongation at break, flexural strength, and impact strength of PVA/DPL biocomposites were investigated and compared with that of virgin PVA matrix. It was found that the above properties were first increased with fiber loading and then decreased. The optimum properties were obtained at 28 wt% of DPL fiber. The storage modulus and tan delta values of PVA/DPL biocomposites were analyzed. The thermal properties of biocomposites were also studied through the results of thermogravimetric (TGA). POLYM. COMPOS., 34:959–966, 2013. © 2013 Society of Plastics Engineers
The photodegradation and biodegradation of rEPS/curaua fiber composites
Authors: Borsoi Cleide , Berwig Karina H. , Scienza Lisete C. , Zattera Ademir J.
Published: May 2013

The development of composite materials comprised of postconsumer polymers and natural fibers is important for the possibility to obtain materials that are more compatible with the environment. Depending on the application of these materials and their final disposal, the relevant degradation processes must be considered in the studies of these materials. The aim of this work is to evaluate the effect of the degradation process in simulated soil and in the aging accelerated UV chamber on the properties (tensile strength, chemical, morphology) of the composites developed with recycled expanded polystyrene matrix reinforced by curaua fiber. In the tensile strength tests, it was found that the presence of the curaua fiber and the coupling agent did not have significant effect in the degradation processes of the polymer matrix. However, the use of the coupling agent without the addition of fiber curaua promoted the accelerated degradation of the matrix. The carbonyl index was used as the main assessment parameter of the degradation of the composites, since an increasing in the carbonyl index was observed in the initial periods of degradation decreasing for longer time periods. The presence of cracks in the samples following exposure to UV was observed, but no biofilm formation was identified in the samples exposed to the simulated soil. POLYM. COMPOS., 34:967–977, 2013. © 2013 Society of Plastics Engineers
Synthesis of highly conductive PPy/graphene nanosheets/NiO composite using ultrasonic technique
Authors: Sun Wanhong , Meng Shujuan , Zang Rongxin , Chen Lihua , Wang Yanbin
Published: May 2013

Highly conductive polypyrrole/graphene nanosheets/NiO (PPy/GNS/NiO) composites are fabricated via ultrasound technique using p‐toluenesulfonic acid as a dopant and FeCl3 as an oxidant. The effects of the GNS and NiO loading on the electrical conductivity are investigated. The maximum conductivity of PPy/GNS/NiO composites about 24.39 S/cm found with 3 wt% GNS and 48.7 wt% NiO at room temperature. The results showed that the high‐aspect‐ratio structure of GNS played an important role in forming a conducting network in PPy matrix. The microstructures of PPy/GNS/NiO are evidenced by the scanning electron microscope and transmission electron microscope examinations. The cyclic voltammetry curves can be seen that the PPy/GNS/NiO composites also have good electrochemical performance, and it can be used as a supercapacitor electrode material. POLYM. COMPOS., 34:997–1002, 2013. © 2013 Society of Plastics Engineers
Chemically Polymerization Mechanism of Aromatic Compounds under Atmospheric Pressure Plasma Conditions
Authors: Asandulesa Mihai , Topala Ionut , Pohoata Valentin , Legrand Yves Marie , Dobromir Marius , Totolin Marian , Dumitrascu Nicoleta
Published: May 2013

The multitude of chemically reactive species that are involved in plasma polymerization process make difficult to anticipate how the polymer will look like. In order to prepare polymerized films with imposed properties a good control over the plasma polymerization reaction should be done. In this paper, we investigate plasma polymerization reactions of aromatic compounds using a cold atmospheric pressure glow discharge working in helium. The structure of polymerized films was determined using infrared spectroscopy, X‐ray photoelectron spectroscopy, and nuclear magnetic resonance spectroscopy. Furthermore, the results of spectroscopic analyses allowed us to develop a polymerization mechanism from a chemical point of view related to formation of plasma‐polymerized films.

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Preparation and Characterization of Insensitive HMX/Graphene Oxide Composites
Authors: Li Rui , Wang Jun , Shen Jin Peng , Hua Cheng , Yang Guang Cheng
Published: May 2013

To improve the safety of HMX, a two‐dimensional (2D) graphene oxide (GO) was introduced to HMX by the solventnonsolvent method. The morphology, composition, thermal decomposition characteristic were characterized by scanning electron microscopy (SEM), X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), thermogravimetry (TG) and differential scanning calorimetry (DSC). Compared to the previous reports, GO sheets exhibited better desensitizing effect than [60]Fullerene and CNTs. When 2.0 wt‐% GO sheets were added, the impact sensitivity of raw HMX decreased from 100 to 10 %, and the friction sensitivity reduced from 100 to 32 %. The DSC results proved that GO sheets were compatible with HMX. In addition, by determining the thermal decomposition kinetic parameters of the samples, it was found that the activation energy (Ea) of HMX with 2.0 wt‐% GO increased by 23.5 kJ mol−1, suggesting that GO sheets could improve the thermal stability of HMX.
Ligand promiscuity through the eyes of the aminoglycoside N3 acetyltransferase IIa
Authors: Norris Adrianne L. , Serpersu Engin H.
Published: May 2013

Aminoglycoside‐modifying enzymes (AGMEs) are expressed in many pathogenic bacteria and cause resistance to aminoglycoside (AG) antibiotics. Remarkably, the substrate promiscuity of AGMEs is quite variable. The molecular basis for such ligand promiscuity is largely unknown as there is not an obvious link between amino acid sequence or structure and the antibiotic profiles of AGMEs. To address this issue, this article presents the first kinetic and thermodynamic characterization of one of the least promiscuous AGMEs, the AG N3 acetyltransferase‐IIa (AAC‐IIa) and its comparison to two highly promiscuous AGMEs, the AG N3‐acetyltransferase‐IIIb (AAC‐IIIb) and the AG phosphotransferase(3′)‐IIIa (APH). Despite having similar antibiotic selectivities, AAC‐IIIb and APH catalyze different reactions and share no homology to one another. AAC‐IIa and AAC‐IIIb catalyze the same reaction and are very similar in both amino acid sequence and structure. However, they demonstrate strong differences in their substrate profiles and kinetic and thermodynamic properties. AAC‐IIa and APH are also polar opposites in terms of ligand promiscuity but share no sequence or apparent structural homology. However, they both are highly dynamic and may even contain disordered segments and both adopt well‐defined conformations when AGs are bound. Contrary to this AAC‐IIIb maintains a well‐defined structure even in apo form. Data presented herein suggest that the antibiotic promiscuity of AGMEs may be determined neither by the flexibility of the protein nor the size of the active site cavity alone but strongly modulated or controlled by the effects of the cosubstrate on the dynamic and thermodynamic properties of the enzyme.
A simple, flexible, and effective covariate‐adaptive treatment allocation procedure
Authors: Loux Travis M.
Published: May 2013

We present a method for allocating treatment when subjects arrive in sequence. Based on the theory of propensity scores more commonly used in observational studies, the method balances both discrete and continuous covariates without assuming a model for the outcome. Although we allow for a number of possible specifications, we explore some specific instances in depth. The proposed method is compared with previously suggested sequential randomization and allocation procedures with relationships to some well‐known methods highlighted. Through simulations, the deterministic version is shown to achieve both covariate balance and near optimum efficiency with minimal assumptions. We also investigate the properties of selected randomized versions with respect to both optimality and selection bias. We conclude with an application to a pilot study on weight loss. The proposed method is shown to be robust to the number of covariates balanced and the marginal and joint distributions of those covariates. Copyright © 2013 John Wiley & Sons, Ltd.
Intrafetal laser treatment for twin reversed arterial perfusion sequence: cohort study and meta‐analysis
Authors: Pagani G. , D'Antonio F. , Khalil A. , Papageorghiou A. , Bhide A. , Thilaganathan B.
Published: May 2013

Objectives

To ascertain the outcome of twin reversed arterial perfusion (TRAP) sequence cases managed in our unit and to review systematically cases reported in the literature treated with intrafetal laser therapy.

Methods

This was a retrospective cohort study of all TRAP sequence cases identified from 2000 to 2012 at our center. Pregnancy management and outcomes were ascertained from maternal and neonatal records. We also performed a meta‐analysis of the literature on the use of intrafetal laser therapy for the treatment of TRAP. Adverse pregnancy outcome was defined as a composite of intrauterine death (IUD) and preterm birth before 37 weeks' gestation.

Results

Twenty‐three cases of TRAP were identified during the study period. Six were managed conservatively and 17 were treated with laser therapy. All cases managed conservatively were complicated by IUD at a median gestational age of 14 + 4 (interquartile range (IQR), 12 + 4 to 16 + 5) weeks. Among the treated cases, 14 (82%) delivered a healthy twin at a median gestational age of 37 + 1 (IQR, 34 + 0 to 38 + 3) weeks. Ten studies were reviewed in detail and the data were combined with those from the current study. The overall neonatal survival was 80%. Adverse pregnancy outcome was significantly lower when the treatment was performed before 16 weeks' gestation (19 vs 66%, P = 0.0025).

Conclusion

The study data demonstrate a high risk of spontaneous fetal demise in early pregnancy, lack of accurate prognostic markers and improved pregnancy outcome after laser therapy in cases of TRAP. In these cases we recommend elective treatment with intrafetal laser therapy at between 13 and 16 weeks' gestation. Copyright © 2013 ISUOG. Published by John Wiley & Sons Ltd.
Distortion of the anterior part of the interhemispheric fissure: significance and implications for prenatal diagnosis
Authors: Vinurel N. , Van Nieuwenhuyse A. , Cagneaux M. , Garel C. , Quarello E. , Brasseur M. , Picone O. , Ferry M. , Gaucherand P. , des Portes V. , Guibaud L.
Published: May 2013

In order to illustrate the significance of a new anatomical finding, distortion of the interhemispheric fissure (DIHF) associated with impacted medial borders of the frontal lobes, we report a retrospective observational study of 13 fetuses in which DIHF was identified on prenatal imaging. In 10 cases there were associated anatomical anomalies, including mainly midline anomalies (syntelencephaly (n = 2), lobar holoprosencephaly (n = 1), Aicardi syndrome (n = 2)), but also schizencephaly (n = 1), cortical dysplasia (n = 1) and more complex cerebral malformations (n = 3), including neural tube defect in two cases. Chromosomal anomaly was identified in two cases, including 6p deletion in a case without associated central nervous system anomalies and a complex mosaicism in one of the cases with syntelencephaly. In two cases, the finding was apparently isolated on both pre‐ and postnatal imaging, and the children were doing well at follow‐up, aged 4 and 5 years. The presence of DIHF on prenatal imaging may help in the diagnosis of cerebral anomalies, especially those involving the midline. If DIHF is apparently isolated on prenatal ultrasound, magnetic resonance imaging is recommended for careful analysis of gyration and midline, especially optic and olfactory structures. Karyotyping is also recommended. Copyright © 2013 ISUOG. Published by John Wiley & Sons Ltd
Synthesis and characterization of a calcium‐ and sodium‐containing acrylamide‐based polymer and its effect on soil strength
Authors: Rabiee Ahmad , Gilani Mahdi , Jamshidi Hajar , Baharvand Habibollah
Published: May 2013

Soil degradation is a significant problem throughout the world. One strategy that can be used to improve soil physical properties is the use of soil conditioners, particularly anionic polyacrylamides. Synthetic water‐soluble anionic acrylamide‐based polymers have wide applications in agriculture, such as mulch and agrochemicals, and can also be used as soil modifiers for erosion control, nondesertification, and soil stabilization. In this study, anionic polyacrylamides containing cationic metal ions were prepared by free‐radical polymerization. Anionic polymer with negative charges was produced by the reaction of mono‐ and divalent inorganic salts with acrylamide monomer via solution polymerization. Hydrolysis of the polymer was carried out by using calcium chloride and sodium carbonate in their soluble forms, and the negative charges on the polymer were regulated by variation of the molar ratios of inorganic salts with respect to the acrylamide monomer concentration. The molecular weight and charge density of the anionic charged polymers were improved and manipulated by using these methods. The molecular structure of the polymers was characterized and confirmed by common techniques. The effect of the polymers on soil strength was evaluated, and the results showed that the addition of anionic polymer having a high molecular weight improved the behavior of soil components. J. VINYL ADDIT. TECHNOL., 19:140–146, 2013. © 2013 Society of Plastics Engineers
Bioenergy options for New Zealand: key findings from five studies
Authors: Hall Peter
Published: May 2013

Studies on bioenergy opportunities available to New Zealand found wood from plantation forests is the largest biomass resource and the one with most potential to expand. The use of municipal solid wastes and industrial effluents for energy gave significant environmental benefits, but makes a small contribution to total energy demand. The potential of plantation forests to create a carbon store, garner environmental benefits, and create lumber and energy supplies are substantial. After considering several aspects, including domestic energy supply and demand, key to maximizing these benefits for New Zealand is the development of biomass to liquid fuels conversion technologies, focused on wood to drop‐in liquid fuels. Establishment of large‐scale woody biomass resources producing multiple products including energy could mitigate risks associated with other bioenergy options by

Being based on an existing industry;

Not impacting exports from arable and high‐value pastoral land;

Acting as significant long‐term energy store;

Providing carbon sequestration during establishment and growingphases and additional carbon stocks from new forest area;

Providing environmental services, stabilizing erosion prone land, provid‐ing low‐input (fertilizer, pesticides) land use, and improving waterquality;

Producing sustainable coproducts, traditional timber products, and high‐value biomaterials and chemicals;

Providing the forest industry with a significant alternative market for low‐value log products;

Stimulating regional development;

Providing year round biomass supply.

The opportunity to substitute fossil fuels with domestically produced biofuels could bring long‐term economic and environmental benefits to the country through better utilizing New Zealand's natural capital.

This article is categorized under:

Bioenergy > Economics and Policy

Bioenergy > Systems and Infrastructure

Bioenergy > Climate and Environment
Learning Tools and Simulation in Robotic Surgery: State of the Art
Authors: Buchs Nicolas C. , Pugin François , Volonté Francesco , Morel Philippe
Published: May 2013

Robotic surgery has emerged as a new technology over the last decade and has brought with it new challenges, particularly in terms of teaching and training. To overcome these challenges, robotic courses, virtual simulation, and dual consoles have been successfully introduced. In fact, there are several simulators currently on the market that have proven to be a valid option for training, especially for the novice trainee. Robotic courses have also found success around the world, allowing participants to implement robotic programs at their institution, typically with the help of a proctor. More recently, the dual console has enabled two surgeons to be operating at the same time. Having one experienced surgeon and one trainee each at his or her own console has made it an obvious choice for training. Although these methods have been successfully introduced, the data remain relatively scarce concerning their role in training. The aim of this article was to review the various methods and tools involved in the training of surgeons in robotic surgery.
Quorum-sensing inhibitory compounds from extremophilic microorganisms isolated from a hypersaline cyanobacterial mat
Authors: Abed Raeid M M , Dobretsov Sergey , Al-Fori Marwan , Gunasekera Sarath P , Sudesh Kumar , Paul Valerie J
Published: May 2013

In this study, extremely halophilic and moderately thermophilic microorganisms from a hypersaline microbial mat were screened for their ability to produce antibacterial, antidiatom, antialgal, and quorum-sensing (QS) inhibitory compounds. Five bacterial strains belonging to the genera Marinobacter and Halomonas and one archaeal strain belonging to the genus Haloterrigena were isolated from a microbial mat. The strains were able to grow at a maximum salinity of 22–25 % and a maximum temperature of 45–60 °C. Hexanes, dichloromethane, and butanol extracts from the strains inhibited the growth of at least one out of nine human pathogens. Only butanol extracts of supernatants of Halomonas sp. SK-1 inhibited growth of the microalga Dunaliella salina. Most extracts from isolates inhibited QS of the acyl homoserine lactone producer and reporter Chromobacterium violaceum CV017. Purification of QS inhibitory dichloromethane extracts of Marinobacter sp. SK-3 resulted in isolation of four related diketopiperazines (DKPs): cyclo(l-Pro-l-Phe), cyclo(l-Pro-l-Leu), cyclo(l-Pro-l-isoLeu), and cyclo(l-Pro-d-Phe). QS inhibitory properties of these DKPs were tested using C. violaceum CV017 and Escherichia coli-based QS reporters (pSB401 and pSB1075) deficient in AHL production. Cyclo(l-Pro-l-Phe) and cyclo(l-Pro-l-isoLeu) inhibited QS-dependent production of violacein by C. violaceum CV017. Cyclo(l-Pro-l-Phe), cyclo(l-Pro-l-Leu), and cyclo(l-Pro-l-isoLeu) reduced QS-dependent luminescence of the reporter E. coli pSB401 induced by 3-oxo-C6-HSL. Our study demonstrated the ability of halophilic and moderately thermophilic strains from a hypersaline microbial mat to produce biotechnologically relevant compounds that could be used as antifouling agents.
The Well- and Unwell-Being of a Child
Authors: Schües Christina , Rehmann-Sutter Christoph
Published: May 2013

The concept of the ‘well-being of the child’ (like the ‘child’s welfare’ and ‘best interests of the child’) has remained underdetermined in legal and ethical texts on the needs and rights of children. As a hypothetical construct that draws attention to the child’s long-term welfare, the well-being of the child is a broader concept than autonomy and happiness. This paper clarifies some conceptual issues of the well-being of the child from a philosophical point of view. The main question is how well-being could in practice acquire a concrete meaning and content for a particular issue or situation. A phenomenological-hermeneutic research perspective will be outlined that allows the child’s well-being to be elucidated and specified as an anthropological and ethical idea. It is based on a contextual understanding of generative relationships, a combination of the theory and practice of making sense, here described as ‘generative insight’, which could provide ethical guidance for decision making in families, legal practice, medicine or biomedical research.
The Free Fillet Flap after Traumatic Amputation: A Review of Literature and Case Report
Authors: Machol Jacques A. , Fang Robert C. , Matloub Hani S.
Published: May 2013

Severe, mutilating hand injuries present difficult reconstructive scenarios. Often in these cases, portions of the amputated tissue may be used for reconstruction of the remaining digits and hand using the spare parts principle. The free fillet flap follows the spare parts concept. A literature review of free fillet flaps for hand and forearm coverage is provided. We also present a case report of a multi-digit and dorsal hand free fillet flap for coverage of a traumatic metacarpal hand. This flap demonstrates the value of ingenuity in planning during emergent trauma reconstruction.
Production and Characterization of DHA and GLA‐Enriched Structured Lipid from Palm Olein for Infant Formula Use
Authors: Nagachinta Supakana , Akoh Casimir C.
Published: May 2013

Palm olein was modified via lipase‐catalyzed acidolysis reaction to obtain fatty acid composition and positional distribution similar to human milk fat. In the reaction, a free fatty acid mix containing 23.23 % docosahexaenoic (DHA), 31.42 % gamma‐linolenic (GLA), and 15.12 % palmitic acid was employed. The DHA and GLA were incorporated into the structured lipid (SL) product to improve its nutritional value. Response surface methodology (RSM) was used to investigate the effects of reaction time and substrate mole ratio (palm olein to a free fatty acid mix) on the amount of palmitic acid at the sn‐2 position of SL triacyglycerols (TAG), and on the total DHA and GLA incorporation. Gram‐scale production of SL was performed using the conditions predicted by RSM to maximize the content of palmitic acid at the sn‐2 position. Verification of the predictions from RSM confirmed its practical utility. The resulting SL had 35.11 % palmitic acid at the sn‐2 position, with 3.75 % DHA and 5.03 % GLA. Differential scanning calorimetry and HPLC analyses of the TAG revealed changes in their polymorphic profiles and TAG molecular species of SL compared to palm olein. The SL from this study can potentially be used in infant formula formulations.
Hysteroscopic adhesiolysis for patients with Asherman's syndrome: menstrual and fertility outcomes
Authors: Yamamoto Nari , Takeuchi Reiko , Izuchi Daisuke , Yuge Norihito , Miyazaki Masahide , Yasunaga Masafumi , Egashira Katsuko , Ueoka Yousuke , Inoue Yoshihito
Published: May 2013

Purpose

Most patients with Asherman's syndrome present with infertility and menstrual problems. In this retrospective clinical study, we analyzed patients with Asherman's syndrome who underwent hysteroscopic adhesiolysis to examine their associated symptoms, disease etiologies, and fertility outcomes.

Methods

Twenty‐seven patients with Asherman's syndrome that were diagnosed using hysteroscopy were recruited. The chief complaints were infertility, hypomenorrhea, and amenorrhea. Each case of Asherman's syndrome was classified according to the American Fertility Society classification. Hysteroscopic adhesiolysis was performed in all cases and concomitant transabdominal ultrasonography was conducted in cases with extensive and dense adhesions.

Results

There were no complications associated with the hysteroscopic procedure. Normal menstrual cycles resumed in all cases. Of the 16 infertile patients, 9 conceived. Three patients achieved term deliveries and one patient is currently pregnant. None of the patients had obstetric complications. Two patients had spontaneous abortions, one had an ectopic pregnancy, one had an abortion at 16 weeks’ gestation due to cervical incompetence, and one had a molar pregnancy and required uterine artery embolization for uncontrolled hemorrhaging during a dilatation and curettage procedure.

Conclusions

Hysteroscopic adhesiolysis with transabdominal ultrasonography is a suitable treatment method for Asherman's syndrome. Subfertile patients with Asherman's syndrome undergoing adhesiolysis should be appropriately informed about the risk of associated life‐threatening complications and preterm delivery.