bluuebunny/crossref_metadata_2025 huggingface dataset:
Mixed Oxide Supported MoO3 Catalyst: Preparation, Characterization and Activities in Nitration of o-xylene
Authors: Kemdeo S. M. , Sapkal V. S. , Chaudhari G. N.
Published: July 2014

TiO2-ZrO2 mixed oxide support was prepared and impregnated with 12 wt % MoO3 and calcined at various temperatures. The resultant catalyst systems were characterized by XRD, FT-IR, BET, SEM, NH3-TPD and pyridine adsorbed FT-IR methods to know the physico-chemical changes occurred in course of thermal treatment. Activities of these catalysts were tested by employing them in the nitration of o-xylene. Mostly, 500 oC calcined catalyst sample was found to be most active for nitration reaction. Catalyst calcined at higher temperatures showed the negative influence on o-xylene conversion and 4-nitro-o-xylene selectivity. Conversion can be correlated with the presence of strong Brönsted acid sites over the catalyst surface whereas change in selectivity was found attributed to the pore diameter of the catalyst. These catalysts also performed satisfactorily, when used for nitration of other aromatics. No use of corrosive sulfuric acid and efficient reusability of the catalyst make the process environmentally friendly and economic. © 2010 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0)
Hydrodynamic Studies on a Trickle Bed Reactor for Foaming Liquids
Authors: Gupta Renu , Bansal Ajay
Published: July 2014

Hydrodynamic studies of trickle bed reactors (TBRs) are essential for the design and prediction of their performance. The hydrodynamic characteristics involving pressure drop and dynamic liquid saturation are greatly affected by the physical properties of the liquids. In the present study experiments have been carried out in a concurrent downflow air - liquid trickle bed reactor to investigate the dynamic liquid saturation and pressure drop for the water (non-foaming) and 3% polyethylene glycol and 4% polyethylene glycol foaming liquids in the gas continuous regime (GCF) and foaming pulsing regime (FP). In the GCF regime the dynamic liquid saturation was found to increase with increase in liquid flow rate for non-foaming and foaming liquids. While for 3% and 4% polyethylene glycol solutions the severe foaming was observed in the high interaction regime and the regime is referred to as foaming pulsing (FP) regime. The decrease in dynamic liquid saturation followed by a sharp rise in the pressure drop was observed during transition from gas GCF to FP regime. However in the FP regime, a dip in the dynamic liquid saturation was observed. The pressure drop for foaming liquids is observed to be manifolds higher compared to non-foaming liquid in the GCF regime.  © 2010 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0)
Potential of LiNO3/Al2O3 Catalyst for Heterogeneous Transesterification of Palm Oil to Biodiesel
Authors: Istadi Istadi , Pramudono Bambang , Suherman Suherman , Priyanto Slamet
Published: July 2014

Production of biodiesel through transesterification process using heterogenous catalysts in order to avoid the saponification problem was studied. In this process, palm oil reacted with methanol to form a mixture of glycerol and biodiese over a solid basic catalyst. One type of the catalysts used in this research is basic catalyst of LiNO3/Al2O3. The parameters studied in this research are concentration of LiNO3 loading on Al2O3 and effect of different reaction time. The products was analyzed using Gas Chromatography to determine composition and yield of resulted methyl esters as well as conversion of palm oil to biodiesel. The major products in this transesterification reaction were biodiesel and glycerol. It can be concluded that the 20 wt% LiNO3/Al2O3 catalyst is potential for producing biodiesel from palm oil over transesterification reaction. Advantages of the usage of this catalyst is that the soap formation was not observed in this research. © 2010 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0)
ENU Mutagenesis in the Mouse
Authors: Stottmann Rolf , Beier David
Published: July 2014

This unit describes the treatment of laboratory mice with the mutagen N‐ethyl‐N‐nitrosourea (ENU) to induce very highly increased rates of mutation throughout the genome. Further, it describes several popular mating schemes designed to produce animals displaying phenotypes associated with the induced mutations. Curr. Protoc. Hum. Genet. 82:15.4.1‐15.4.10 © 2014 by John Wiley & Sons, Inc.
Getting Started with Microbiome Analysis: Sample Acquisition to Bioinformatics
Authors: Kumar Ranjit , Eipers Peter , Little Rebecca B. , Crowley Michael , Crossman David K. , Lefkowitz Elliot J. , Morrow Casey D.
Published: July 2014

Historically, in order to study microbes, it was necessary to grow them in the laboratory. It was clear though that many microbe communities were refractory to study because none of the members could be grown outside of their native habitat. The development of culture‐independent methods to study microbiota using high‐throughput sequencing of the 16S ribosomal RNA gene variable regions present in all prokaryotic organisms has provided new opportunities to investigate complex microbial communities. In this unit, the process for a microbiome analysis is described. Many of the components required for this process may already exist. A pipeline is described for acquisition of samples from different sites on the human body, isolation of microbial DNA, and DNA sequencing using the Illumina MiSeq sequencing platform. Finally, a new analytical workflow for basic bioinformatics data analysis, QWRAP, is described, which can be used by clinical and basic science investigators. Curr. Protoc. Hum. Genet. 82:18.8.1‐18.8.29. © 2014 by John Wiley & Sons, Inc.
An intercomparison of Arctic ice drift products to deduce uncertainty estimates
Authors: Sumata Hiroshi , Lavergne Thomas , Girard‐Ardhuin Fanny , Kimura Noriaki , Tschudi Mark A. , Kauker Frank , Karcher Michael , Gerdes Rüdiger
Published: July 2014

An intercomparison of four low‐resolution remotely sensed ice‐drift products in the Arctic Ocean is presented. The purpose of the study is to examine the uncertainty in space and time of these different drift products. The comparison is based on monthly mean ice drifts from October 2002 to December 2006. The ice drifts were also compared with available buoy data. The result shows that the differences of the drift vectors are not spatially uniform, but are covariant with ice concentration and thickness. In high (low) ice‐concentration areas, the differences are small (large), and in thick (thin) ice‐thickness areas, the differences are small (large). A comparison with the drift deduced from buoys reveals that the error of the drift speed depends on the magnitude of the drift speed: larger drift speeds have larger errors. Based on the intercomparison of the products and comparison with buoy data, uncertainties of the monthly mean drift are estimated. The estimated uncertainty maps reasonably reflect the difference between the products in relation to ice concentration and the bias from the buoy drift in relation to drift speed. Examinations of distinctive features of Arctic sea ice motion demonstrate that the transpolar drift speed differs among the products by 13% (0.32 cm s−1) on average, and ice drift curl in the Amerasian Basin differs by up to 24% (3.3 × 104 m2 s−1). These uncertainties should be taken into account if these products are used, particularly for model validation and data assimilation within the Arctic.
The spatial scale dependence of water vapor variability inferred from observations from a very tall tower
Authors: Pressel Kyle G. , Collins William D. , Desai Ankur R.
Published: July 2014

Recent studies have established that atmospheric water vapor fields exhibit spatial spectra that take the form of power laws and hence can be compactly characterized by scaling exponents. The power law scaling exponents have been shown to exhibit substantial vertical variability. In this work, Taylor's frozen turbulence hypothesis is used to infer the first‐order spatial structure function and generalized detrended fluctuation function scaling exponents for scales between 1 km and 100 km. Both methods are used to estimate the Hurst exponent (H) using 10 Hz time series of water vapor measured at 396 m altitude from an Ameriflux tower in Wisconsin. Due to the diurnal cycle in the boundary layer height at the 396 m observational level, H may be estimated for both the daytime convective mixed layer and the nocturnal residual layer. Values of are obtained for the convective mixed layer, while values of apply in the nocturnal residual layer. The results are shown to be remarkably consistent with a similar analysis from satellite‐based observations as reported in Pressel and Collins (2012).
Accelerated flooding along the U.S. East Coast: On the impact of sea‐level rise, tides, storms, the Gulf Stream, and the North Atlantic Oscillations
Authors: Ezer Tal , Atkinson Larry P.
Published: July 2014

Recent studies identified the U.S. East Coast north of Cape Hatteras as a “hotspot” for accelerated sea‐level rise (SLR), and the analysis presented here shows that the area is also a “hotspot for accelerated flooding.” The duration of minor tidal flooding [defined as 0.3 m above MHHW (mean higher high water)] has accelerated in recent years for most coastal locations from the Gulf of Maine to Florida. The average increase in annual minor flooding duration was ∼20 h from the period before 1970 to 1971–1990, and ∼50 h from 1971–1990 to 1991–2013; spatial variations in acceleration of flooding resemble the spatial variations of acceleration in sea level. The increase in minor flooding can be predicted from SLR and tidal range, but the frequency of extreme storm surge flooding events (0.9 m above MHHW) is less predictable, and affected by the North Atlantic Oscillations (NAO). The number of extreme storm surge events since 1960 oscillates with a period of ∼15 year and interannual variations in the number of storms are anticorrelated with the NAO index. With higher seas, there are also more flooding events that are unrelated to storm surges. For example, it is demonstrated that week‐long flooding events in Norfolk, VA, are often related to periods of decrease in the Florida Current transport. The results indicate that previously reported connections between decadal variations in the Gulf Stream (GS) and coastal sea level may also apply to short‐term variations, so flood predictions may be improved if the GS influence is considered.
Insights into magmatic processes and hydrothermal alteration of in situ superfast spreading ocean crust at ODP/IODP site 1256 from a cluster analysis of rock magnetic properties
Authors: Dekkers Mark J. , Heslop David , Herrero‐Bervera Emilio , Acton Gary , Krasa David
Published: July 2014

We analyze magnetic properties from Ocean Drilling Program (ODP)/Integrated ODP (IODP) Hole 1256D (6°44.1' N, 91°56.1' W) on the Cocos Plate in ∼15.2 Ma oceanic crust generated by superfast seafloor spreading, the only drill hole that has sampled all three oceanic crust layers in a tectonically undisturbed setting. Fuzzy c‐means cluster analysis and nonlinear mapping are utilized to study down‐hole trends in the ratio of the saturation remanent magnetization and the saturation magnetization, the coercive force, the ratio of the remanent coercive force and coercive force, the low‐field magnetic susceptibility, and the Curie temperature, to evaluate the effects of magmatic and hydrothermal processes on magnetic properties. A statistically robust five cluster solution separates the data predominantly into three clusters that express increasing hydrothermal alteration of the lavas, which differ from two distinct clusters mainly representing the dikes and gabbros. Extensive alteration can obliterate magnetic property differences between lavas, dikes, and gabbros. The imprint of thermochemical alteration on the iron‐titanium oxides is only partially related to the porosity of the rocks. Thus, the analysis complements interpretation based on electrofacies analysis. All clusters display rock magnetic characteristics compatible with an ability to retain a stable natural remanent magnetization suggesting that the entire sampled sequence of ocean crust can contribute to marine magnetic anomalies. Paleointensity determination is difficult because of the propensity of oxyexsolution during laboratory heating and/or the presence of intergrowths. The upper part of the extrusive sequence, the granoblastic dikes, and moderately altered gabbros may contain a comparatively uncontaminated thermoremanent magnetization.
Fault constitutive relations inferred from the 2009‐2010 slow slip event in Guerrero, Mexico
Authors: Maury Julie , Aochi Hideo , Radiguet Mathilde
Published: July 2014

The spatiotemporal evolution of stress state is analyzed during the 2009–2010 Slow Slip Event (SSE) of Guerrero, Mexico, based on the kinematic inversion results and using an integral expression for stress changes. A linear slip weakening behavior is generally observed during the SSE with an average slope of −0.5 ± 0.2MPa/m regardless the perturbation due to the 27 February 2010 Mw = 8.8 Maule, Chile earthquake. This slope remains unchanged before and after the Maule earthquake. However, for some area, the friction behavior changes from slip hardening to slip weakening following the Maule earthquake. The complex trajectory between shear stress and slip velocity is fitted with a rate‐ and state friction law through an inversion. The direct (rate) effect (parameter A) is found to be very small, lower by an order of magnitude than the evolutional (state) effect (parameter B). The characteristic length L is obtained as 5 cm on average.
Migration calculations for water in the exosphere of the Moon: Dusk‐dawn asymmetry, heterogeneous trapping, and D/H fractionation
Authors: Schorghofer Norbert
Published: July 2014

Water ice is trapped in permanently shadowed craters near the lunar poles, where it is thought to have arrived from an exogenic or endogenic source via ballistic hops. We use a model of the migration of water molecules in the lunar exosphere to investigate three problems: (1) A strong continuous source would lead to an enhanced concentration of H2O at the morning terminator but not at the evening terminator. Hence, spectral features observed at both terminators do not suggest that there is diurnal migration of volatiles. (2) Cold trapping after a comet impact leads to an unequal partitioning between the two hemispheres depending on the latitude of the impact but to nearly equal partitioning with respect to longitude. (3) The D/H fractionation as the water molecules migrate toward the poles is small. Hence, the isotopic composition of ice deposits in the cold traps can be related to that of the source.
A statistical study of magnetic field fluctuations in the dayside magnetosheath and their dependence on upstream solar wind conditions
Authors: Dimmock A. P. , Nykyri K. , Pulkkinen T. I.
Published: July 2014

The magnetosheath functions as a natural interface connecting the interplanetary and magnetospheric plasma. Since the magnetosheath houses the shocked solar wind, it is populated with abundant magnetic field turbulence which are generated both locally and externally. Although the steady state magnetosheath is to date relatively well understood, the same cannot be said of transient magnetic perturbations due to their kinetic nature and often complex and numerous generation mechanisms. The current manuscript presents a statistical study of magnetic field fluctuations in the dayside magnetosheath as a function of upstream solar wind conditions. We concentrate on the ambient higher‐frequency fluctuations in the range of 0.1 Hz → 2 Hz. We show evidence that the dawn (quasi‐parallel) flank is visibly prone to higher‐amplitude magnetic perturbations compared to the dusk (quasi‐perpendicular) region. Our statistical data also suggest that the magnitude of turbulence can be visibly enhanced close to the magnetopause during periods of southward interplanetary magnetic field orientations. Faster (> 400 km s−1) solar wind velocities also appear to drive higher‐amplitude perturbations compared to slower speeds. The spatial distribution also suggests some dependence on the magnetic pileup region at the subsolar magnetopause.
Uncertainty of Aquarius sea surface salinity retrieved under rainy conditions and its implication on the water cycle study
Authors: Tang Wenqing , Yueh Simon H. , Fore Alexander G. , Hayashi Akiko , Lee Tong , Lagerloef Gary
Published: July 2014

The uncertainty of Aquarius sea surface salinity (SSS) retrieved under rain is assessed. Rain not only has instantaneous impact on SSS but also interferes with the microwave remote sensing signals, making the task to retrieve SSS under rainy conditions difficult. A rain correction model is developed based on analysis of the L‐band radiometer/scatterometer residual signals after accounting for roughness due to wind and flat surface emissivity. The combined active passive algorithm is used to retrieve SSS in parallel with (CAP_RC) or without rain correction (CAP). The CAP bias against individual ARGO floats increases with rain rate with slope of −0.14 PSU per mm h−1, which reduced to near zero in CAP_RC. On the global monthly basis, CAP_RC is about 0.03 PSU higher than CAP. RMSD against ARGO is slightly smaller for CAP_RC than CAP. Regional biases are examined in areas with frequent rain events. As expected, results show that ΔSSS (CAP_RC‐CAP) is highly correlated with the seasonal precipitation pattern, reaching about 0.2–0.3 PSU under heavy rain. However, ΔSSS shows no correlation with the difference pattern between ARGO and CAP or CAP_RC. This, along with regional analyses, suggests that the difference between ARGO and Aquarius' SSS is likely caused by the different spatial and temporal sampling, in addition to near surface stratification depicted by radiometer and ARGO at different depths. The effect of ΔSSS on water cycle in terms of mixed‐layer salt storage tendency is about 10% in areas where evaporation‐minus‐precipitation is the dominant process driving the variability of near surface salinity.
Radiosonde observational evidence of the impact of an extremely cold SST spot on a mesoscale anticyclone
Authors: Nishikawa Hatsumi , Tachibana Yoshihiro , Udagawa Yusuke
Published: July 2014

Radiosondes were launched in August 2006 from a research vessel above a spot around the Kuril Islands between the North Pacific and the Okhotsk Sea characterized by an extremely cold sea surface temperature (SST) and a large horizontal temperature gradient caused by strong tidal mixing. Because this cold SST was caused solely by this oceanic process, the observed data chiefly reflect the oceanic influence on the atmosphere. In this area, where the summertime SST is typically lower than in other seas in the same latitude belt, a minimum SST of 2°C and a horizontal gradient of 7°C/10 km were observed in August 2006. During the cruise, the area was covered by a layer of fog up to about 1000 m thick. The following observations reveal the presence of an atmospheric mesoscale anticyclone and a cold dome caused by ocean cooling of the atmosphere. The wind direction over the cold spot and the strong gradient region was northeasterly below the altitude of about 500 m, in contrast to the southwesterly geostrophic wind, and the area of northeasterly wind was characterized by a cold air mass and a high‐pressure anomaly. This ageostrophic wind distribution indicates mesoscale anticyclonic circulation below 500 m. The fog layer was also thinner in the northeasterly wind area than in other areas, suggesting vertical dry air advection (i.e., a subsidence) associated with the mesoscale anticyclone. In addition, our observational results suggest that the pressure adjustment mechanism can explain this mesoscale circulation.
Age and composition of meta‐ophiolite from the Rhodope Middle Allochthon (Satovcha, Bulgaria): A test for the maximum‐allochthony hypothesis of the Hellenides
Authors: Froitzheim Nikolaus , Jahn‐Awe Silke , Frei Dirk , Wainwright Ashlea N. , Maas Roland , Georgiev Neven , Nagel Thorsten J. , Pleuger Jan
Published: July 2014

The metamorphosed thrust stack of the Rhodopes comprises a level with ophiolites (Middle Allochthon) underlain and overlain by continent‐derived allochthons. The Upper Allochthon represents the European margin, but the origin of the Lower Allochthon remains controversial, with suggestions that it may be derived from an inferred microcontinent (Drama) or from the margin of Adria. Trace element compositions and Sr and Nd isotope ratios of metagabbroic amphibolites and enclosed meta‐plagiogranites from the Satovcha Ophiolite, Middle Allochthon, show that they are cogenetic and represent suprasubduction zone ophiolites. U‐Pb dating using laser ablation sector field inductively coupled plasma mass spectrometry of zircons from two meta‐plagiogranites and a metagabbro yielded identical Jurassic ages (160 ± 1 Ma, 160.6 ± 1.8 Ma, and 160 ± 1 Ma, respectively), similar to ophiolites in the eastern Vardar Zone bordering the Rhodopes to the SW. The trace element patterns also closely resemble those of the Vardar ophiolites. The association with Late Jurassic arc‐type granitoids is another feature that applies both to eastern Vardar and Satovcha. This strongly suggests that the Middle Allochthon comprises the metamorphosed northeastward continuation of the Vardar Zone. The Jurassic age of the Satovcha Ophiolite contradicts the hypothesis of Early Jurassic suturing between Europe (Upper Allochthon) and the assumed Drama microcontinent (Lower Allochthon) but is in line with the “maximum allochthony hypothesis,” i.e., the assumption that the Lower Allochthon represents Adria and that the “root” of the Vardar‐derived thrust sheets is at the NE boundary of the Rhodopes.
Plant Viruses: Soil‐borne
Authors: Roberts Alison G
Published: July 2014

A number of plant viruses in different genera are harboured in and transmitted through the soil. They are found throughout the world and several of them cause significant economic losses to major crops. Vectors for spread of these viruses are fungal‐like organisms or plant‐parasitic nematodes, but some viruses can also be exuded from infected roots and transmitted abiotically, without the aid of a vector. The long‐term persistence of these viruses in soil, often for decades, and a lack of efficient control strategies mean that diseases caused by these viruses are very difficult to control. Eradication of inoculum from infected soil is almost impossible, particularly in those parts of the world where highly toxic soil fumigant chemicals have been banned in recent years. Soil‐borne viruses are difficult to study and their biology is relatively poorly understood at present.

Key Concepts:

A number of plant viruses are transmitted through the soil or by soil‐borne vectors to plant roots.

Soil‐borne viruses infect several economically important crops including wheat, barley, potato, sugar beet, groundnut and fruit crops.

Soil‐borne viruses belong to fifteen named and two currently unnamed genera that fall within the
Secoviridae
,
Potyviridae
,
Ophioviridae
,
Tombusviridae
or
Virgaviridae
families, or have not yet been assigned to a virus family.

The main vectors for soil‐borne viruses are trichodorid or longidorid nematodes, chytrid fungi in the genus
Olpidium
and plasmodiophorids in the genera
Polymyxa
or
Spongospora
.

Soil‐borne viruses are relatively poorly understood due to a combination of factors including the complexity of the plant–vector–virus interaction and the fact that soil impedes observations of their biology.

Soil‐borne viruses are very persistent; they can exist for decades in the soil in long‐lived resting spores of their vectors making eradication of disease very difficult once soil is contaminated.

There are few effective means available to control soil‐borne viruses; few resistant cultivars are available and chemical methods of control are generally expensive and highly toxic.
Scaling the Stiffness, Strength, and Toughness of Ceramic‐Coated Nanotube Foams into the Structural Regime
Authors: Brieland‐Shoultz Anna , Tawfick Sameh , Park Sei Jin , Bedewy Mostafa , Maschmann Matthew R. , Baur Jeffery W. , Hart A. John
Published: July 2014

Natural materials such as bone and tooth achieve precisely tuned mechanical and interfacial properties by varying the concentration and orientation of their nanoscale constituents. However, the realization of such control in engineered foams is limited by manufacturing‐driven tradeoffs among the size, order, and dispersion uniformity of the building blocks. It is demonstrated how to manufacture nanocomposite foams with precisely controllable mechanical properties via aligned carbon nanotube (CNT) growth followed by atomic layer deposition (ALD). By starting with a low density CNT forest and varying the ALD coating thickness, we realize predictable ≈1000‐fold control of Young's modulus (14 MPa to 20 GPa, where E ∼ ρ
2.8), ultimate compressive strength (0.8 MPa to 0.16 GPa), and energy absorption (0.4 to 400 J cm–3). Owing to the continuous, long CNTs within the ceramic nanocomposite, the compressive strength and toughness of the new material are 10‐fold greater than commercially available aluminum foam over the same density range. Moreover, the compressive stiffness and strength equal that of compact bone at 10% lower density. Along with emerging technologies for scalable patterning and roll‐to‐roll manufacturing and lamination of CNT films, coated CNT foams may be especially suited to multifunctional applications such as catalysis, filtration, and thermal protection.
Highly Conductive Carbon Nanotube‐Graphene Hybrid Yarn
Authors: Foroughi Javad , Spinks Geoffrey M. , Antiohos Dennis , Mirabedini Azadehsadat , Gambhir Sanjeev , Wallace Gordon G. , Ghorbani Shaban R. , Peleckis Germanas , Kozlov Mikhail E. , Lima Marcio D. , Baughman Ray H.
Published: July 2014

An efficient procedure for the fabrication of highly conductive carbon nanotube/graphene hybrid yarns has been developed. To start, arrays of vertically aligned multi‐walled carbon nanotubes (MWNT) are converted into indefinitely long MWNT sheets by drawing. Graphene flakes are then deposited onto the MWNT sheets by electrospinning to form a composite structure that is transformed into yarn filaments by twisting. The process is scalable for yarn fabrication on an industrial scale. Prepared materials are characterized by electron microscopy, electrical, mechanical, and electrochemical measurements. It is found that the electrical conductivity of the composite MWNT‐graphene yarns is over 900 S/cm. This value is 400% and 1250% higher than electrical conductivity of pristine MWNT yarns or graphene paper, respectively. The increase in conductivity is asssociated with the increase of the density of states near the Fermi level by a factor of 100 and a decrease in the hopping distance by an order of magnitude induced by grapene flakes. It is found also that the MWNT‐graphene yarn has a strong electrochemical response with specific capacitance in excess of 111 Fg−1. This value is 425% higher than the capacitance of pristine MWNT yarn. Such substantial improvements of key properties of the hybrid material can be associated with the synergy of MWNT and graphene layers in the yarn structure. Prepared hybrid yarns can benefit such applications as high‐performance supercapacitors, batteries, high current capable cables, and artificial muscles.
Poikiloderma with neutropenia: Genotype‐ethnic origin correlation, expanding phenotype and literature review
Authors: Koparir Asuman , Gezdirici Alper , Koparir Erkan , Ulucan Hakan , Yilmaz Mehmet , Erdemir Aslı , Yuksel Adnan , Ozen Mustafa
Published: July 2014

Poikiloderma with neutropenia (PN), is a rare genodermatosis associated with patognomic features of poikiloderma and permanent neutropenia. Three common recurrent mutations of related gene, USB1, were considered to be associated with three different ethnic origins. The most common recurrent mutation, c.531delA, has been detected in seven Caucasian patients in the literature. In this paper, we present review of all patients from the literature and report two additional patients of Turkish ancestry with the diagnosis of PN. The diagnosis of these two PN patients were made clinically and confirmed by molecular analysis which detected the most common recurrent mutation, c.531delA. Genotype‐ethnic origin correlation hypothesis, therefore, has been strengthened with this result. Short stature in PN, is a common finding, which until now has never been treated with growth hormone (GH). One of our patients is the first patient with attempted treatment of short stature via GH administration. Finally, both of our patients had high‐pitched voice and vocal cord nodules which might be considered as additional clinical findings not associated with PN before. © 2014 Wiley Periodicals, Inc.
Variation in the Position of the Jugal Medial Ridge Among Lizards (Reptilia: Squamata): Its Functional and Taxonomic Significance
Authors: Čerňanský Andrej , Smith Krister T. , Klembara Jozef
Published: July 2014

The course of the medial ridge in the lizard jugal shows considerable morphological variation. There are four basic configurations: (1) the medial ridge is located ventral to mid‐height on the suborbital process and anterior to mid‐length on the postorbital process; (2) the medial ridge is located ventrally on the suborbital process (as above), but posteriorly on the postorbital process; (3) the medial ridge is located dorsally on the suborbital process and anteriorly on the postorbital process; and (4) the medial ridge is centrally located along the entire length of the jugal. Ancestral character state reconstruction shows that type 1 is plesiomorphic for Squamata regardless of the broad‐scale phylogenetic topology. Type 3 is present in chamaeleonids and convergently inAnolis barbatus. Type 3 is a synapomorphy of the chamaeleonids. Type 2 is considered plesiomorphic for Anguidae,HelodermaandXenosaurus, although it is independently modified in some extant members. These taxa form a clade in molecular phylogenies of Squamata, and the course of the medial ridge of the jugal therefore provides some measure of morphological support for this arrangement. The course of the medial ridge may be best explained by the position of the eye and by the angle of the jugal; its relations with other bony orbital structures (supraocular osteoderms, palpebral, supraorbital flanges) and the posterior extent of the maxilla are also discussed. Anat Rec, 297:2262–2272, 2014. © 2014 Wiley Periodicals, Inc.
Meta-analysis of pancreaticogastrostomy versus pancreaticojejunostomy after pancreaticoduodenectomy
Authors: Xiong J J , Tan C L , Szatmary P , Huang W , Ke N W , Hu W M , Nunes Q M , Sutton R , Liu X B
Published: July 2014

Background

Surgical reconstruction following pancreaticoduodenectomy (PD) is associated with significant morbidity and mortality. Because of great variability in definitions of specific complications, it remains unclear whether there is a difference in complication rates following the two commonest types of reconstruction, pancreaticogastrostomy (PG) and pancreaticojejunostomy (PJ). Published consensus definitions for postoperative pancreatic fistula (POPF) have led to a series of randomized clinical trials (RCTs) uniquely placed to address this question.

Methods

A literature search was carried out to identify all RCTs comparing postoperative complications of PG versus PJ reconstruction following PD published between January 1995 and December 2013. Pooled odds ratios (ORs) with 95 percent confidence intervals (c.i.) were calculated using fixed-effect or random-effects models.

Results

In total, seven RCTs with 1121 patients were included. Four of these trials applied definitions as published by the International Study Group on Pancreatic Fistula (ISGPF). Using ISGPF definitions, the incidence of POPF was lower in patients undergoing PG than in those having PJ (OR 0·50, 95 per cent c.i. 0·34 to 0·73; P < 0·001). Using definitions applied by each individual study, PG was associated with significantly lower rates of POPF (OR 0·51, 0·36 to 0·71; P < 0·001), intra-abdominal fluid collection (OR 0·50, 0·34 to 0·74; P < 0·001) and biliary fistula (OR 0·42, 0·18 to 0·93; P = 0·03) than PJ.

Conclusion

Meta-analysis of four RCTs based on ISGPF criteria, and seven RCTs using non-standard criteria, revealed that PG reduced the incidence of POPF after PD compared with PJ.
Recurrent syncope after left atrial appendage occlusion
Authors: Cruz‐Gonzalez Ignacio , Perez‐Rivera Jose‐Angel , Bethencourt Armando
Published: July 2014

We present the case of a 72‐year‐old woman with permanent atrial fibrillation and contraindication to long‐term oral anticoagulant therapy who underwent left atrial appendage (LAA) occlusion. A 24‐mm Amplatzer Cardiac Plug (St Jude Medical) device was deployed. The inferior part of the external disc of the device appeared to be over the posterior leaflet of the mitral valve but no significant mitral stenosis or mitral regurgitation was detected before deployment. After the procedure the patient suffered several syncopes when she tried to stand up. A transesophageal echocardiography (TEE) was performed and no significant differences on the device position were detected, it was not possible to perform the TEE in a stand‐up position due to the patient symptoms (hypotension, tachycardia, dizziness, and loss of consciousness). After discussion with the surgical team, surgical removal of the device and surgical exclusion of LAA was performed. The symptoms disappeared and the patient was discharged. In the best of our knowledge, this is the first time that recurrent syncope has been described as a complication of LAA occlusion. © 2014 Wiley Periodicals, Inc.
Aromatic N‐Arylations Catalyzed by Copper‐Anchored Porous Zinc‐Based Metal–Organic Framework under Heterogeneous Conditions
Authors: Maity Tanmoy , Saha Debraj , Koner Subratanath
Published: July 2014

A highly porous Zn‐based metal–organic framework (MOF) IRMOF‐3 was covalently decorated with pyridine‐2‐aldehyde. The free amine group of IRMOF‐3 upon condensation with pyridine‐2‐aldehyde affords a bidentate Schiff‐base moiety in the porous matrix. The Schiff base moieties are availed to anchor copper(II) ions to display the catalyst’s utility towards catalytic reactions. The catalyst was characterized by UV/Vis and IR spectroscopy, powder XRD spectrometry, SEM energy‐dispersive X‐ray spectrometry, and nitrogen sorption measurements. The catalyst exhibits excellent activity in catalyzing the N‐arylation reaction of nitrogen‐containing heterocycles with aryl bromides in DMSO medium, under mild condition (90 °C) in the presence of Cs2CO3. The porous catalyst demonstrates size selectivity towards substrate as a result of the presence of active sites inside the pores of the MOF. The anchored complex seems to be not leached or decomposed during the catalytic reactions up to five successive catalytic cycles, demonstrating practical advantages over homogeneous catalysis.
Boundary control of distributed parameter systems using a discrete state space approach
Authors: Dillabough Megan , Shang Helen , McLellan P. James
Published: July 2014

Many industrial processes exhibit spatially distributed behaviour and are distributed parameter systems (DPS). Much of the current literature has focused on the control of specific types of DPS, such as those modelled by hyperbolic or parabolic partial differential equations (PDEs). Discrete state space models for these systems (termed as 2‐D systems) have also been studied extensively; however, additional techniques are required to deal with boundary control problems. In this article, a discrete 2‐D state space model for boundary control problems is formulated. A controller is developed for boundary control problems using the discrete state space method. Simulation results indicate that the resulting boundary controller can achieve desirable performance for setpoint tracking.
Loss of LKB1 in high‐grade endometrial carcinoma: LKB1 is a novel transcriptional target of p53
Authors: Co Ngai Na , Iglesias David , Celestino Joseph , Kwan Suet Y. , Mok Samuel C. , Schmandt Rosemarie , Lu Karen H.
Published: July 2014

BACKGROUND

Liver kinase B1 (LKB1) is a serine/threonine kinase that functions as a tumor suppressor and regulates cell polarity, proliferation, and metabolism. Mutations in LKB1 are associated with Peutz‐Jeghers syndrome as well as sporadic cervical and lung cancers. Although LKB1‐null mice develop invasive endometrial cancers, the role and regulation of LKB1 in the pathogenesis of human endometrial cancer are not well defined and are the focus of these studies.

METHODS

LKB1 protein and messenger RNA (mRNA) expression levels were evaluated in high‐grade and low‐grade endometrioid endometrial cancer (EEC) and cell lines by reverse transcriptase‐polymerase chain reaction analysis, Western blot analysis, and immunohistochemistry. Mutational and promoter analyses of the LKB1 gene (serine/threonine kinase 11 [STK11]) were performed to identify the mechanisms that contribute to the loss of LKB1 in high‐grade EEC.

RESULTS

Analysis of the LKB1 gene in low‐grade and high‐grade EECs revealed no genetic mutations, suggesting that alterations in LKB1 transcription may be responsible for LKB1 protein loss in high‐grade EEC. Analysis of the LKB1 promoter revealed 4 putative tumor protein 53 (p53) binding sites. Quantitative chromatin immunoprecipitation demonstrated that p53 bound directly to 1 of these sites and increased LKB1 promoter activity 140‐fold. LKB1 promoter activity, mRNA, and protein levels were suppressed after silencing of p53 with small interfering RNA and were elevated in cells that overexpressed p53. Levels of p53 mRNA and protein expression were decreased in high‐grade EEC and were positively correlated with LKB1 protein levels (Spearman correlation, r=0.601; P<.001).

CONCLUSIONS

LKB1 is a direct transcriptional target of p53. The loss of wild‐type p53 in high‐grade EEC may contribute to the LKB1 loss observed in these more aggressive tumors. Cancer 2014;120:3457–3468. © 2014 American Cancer Society.
2‐Phenylquinoline‐Based Cyclometalated Platinum(II) Complexes: Synthesis and Structure–Photoelectric Properties Relationship in Oxygen Sensing
Authors: Liu Chun , Song Xinlong , Wang Zhonggang , Qiu Jieshan
Published: July 2014

Novel 2‐phenylquinoline‐based cyclometalated PtII complexes are synthesized and fully characterized. 2‐Phenylquinoline derivatives with a functional group at the 4‐position of the phenyl ring are prepared through an efficient Pd‐catalyzed ligand‐free and aerobic Suzuki reaction of 2‐bromoquinoline with arylboronic acids. The photophysical properties of the complexes demonstrate that the introduction of a diphenylamino group at the 4‐position of the phenyl ring affects the HOMO level of the PtII complex significantly, resulting in a marked decrease in energy gap. The emission or energy gap is not influenced clearly by other substituents (methyl, cyano, fluoro, trifluoromethyl, methoxyl, carbazol‐9‐yl) at the 4‐position of the phenyl ring. All the complexes show redshifted room‐temperature phosphorescence emission (at 578–599 nm) relative to the model complex Pt(ppy)acac (at 486 nm). The oxygen sensitivity of the complexes is evaluated quantitatively in a polymer film. The films containing the PtII complexes are sensitive to O2, and the luminescence changes gradually and reversibly with O2 concentration. The PtII complex with a triphenylamino moiety exhibits the highest sensitivity (${K{{app\hfill \atop SV\hfill}}}$=0.020 Torr−1). The 2‐phenylquinoline‐based PtII complexes are potential candidates for efficient luminescent oxygen sensing. The present results provide a systematic study on the structure–property relationship between the 2‐phenylquinoline‐based PtII complexes and oxygen sensing.
In situ Observation of Radicals and Molecular Products During Lignin Pyrolysis
Authors: Bährle Christian , Custodis Victoria , Jeschke Gunnar , van Bokhoven Jeroen A. , Vogel Frédéric
Published: July 2014

Lignin pyrolysis is a promising method for the sustainable production of phenolic compounds from biomass. However, detailed knowledge about the radicals involved in this process and their influence on the molecular products is missing. Herein, we report on the pyrolysis of hard‐ and softwood Klason lignins under inert gas conditions in a temperature range between 350–550 °C. During the pyrolysis process, the formed radicals were detected by in situ high‐temperature electron paramagnetic resonance spectroscopy. The overall formation of volatile products during lignin pyrolysis was determined using thermogravimetric analysis. The volatile molecular products were characterized and quantified using GC–MS analysis. Major differences were observed between hardwood and softwood lignins. Hardwood lignins form more radicals and volatile products than softwood lignins at temperatures from 350 to 450 °C. In the late stages of the pyrolysis process at 550 °C radical quenching reactions become dominant in hardwood lignins. We identified the disproportionation of two semiquinone radicals to quinone and hydroquinone species as the most likely quenching reaction. Our results show that both the pyrolysis temperature and the type of lignin source have a major influence on radical formation and the molecular products during the depolymerization of lignin.
Telomere distribution pattern and synapsis initiation during spermatogenesis in zebrafish
Authors: Saito Kenji , Sakai Chiharu , Kawasaki Toshihiroa , Sakai Noriyoshi
Published: July 2014

Background: Telomeres are located at ends of eukaryotic chromosomes and can affect proper chromosomal positioning. During spermatogenesis, the appropriate dynamics and behavior of chromosomes is crucial to generate haploid cells through meiosis. Here, we describe telomere distribution patterns during spermatogenesis in zebrafish, especially during meiotic prophase I, using fluorescence in situ hybridization. This was combined with synaptonemal complex protein 3 immunostaining, which allows the staging of spermatocytes. Results: During spermatogonial proliferation and the preleptotene stage, telomeres were dispersed throughout the nucleus. During the leptotene stage, telomeres temporarily moved to one pole of the nucleus at which γ‐tubulin was located, forming the telomere bouquet. The cluster lasted until the onset of zygotene where it coincided with terminal synapsis initiation. They then spread around the periphery of the nucleus during the zygotene to pachytene stages. During postmeiotic stages, telomeres in spermatids and sperm were again dispersed throughout the nuclei. Application of this procedure in meiotic mutants confirmed that meiotic telomere clustering is independent of axial element formation of the synaptonemal complex. Conclusions: These data clearly showed the clustering and distributions of telomeres throughout spermatogenesis in zebrafish. This procedure could be used to screen for mutants that have primary defects in telomere clustering. Developmental Dynamics 243:1448–1456, 2014. © 2014 Wiley Periodicals, Inc.
Coumarin 6 as a fluorescent model drug: How to identify properties of lipid colloidal drug delivery systems via fluorescence spectroscopy?
Authors: Finke Jan Henrik , Richter Claudia , Gothsch Thomas , Kwade Arno , Büttgenbach Stephanus , Müller‐Goymann Christel C.
Published: July 2014

In the development of colloidal lipid drug delivery systems (DDS), the localization of the drug within the DDS, the protective potential of the DDS as well as the compatibility of the drug with the excipients are of special interest. In this study, Coumarin 6 (C6), a fluorescent dye frequently used to facilitate the traceability of DDS in vitro, is demonstrated as a tool to gain insight into the aforementioned properties by fluorescence spectroscopy. Both ways of loading C6 to solid colloidal DDS (pre‐loading to the lipid matrix or post‐loading to the ready DDS after its processing) led to a localization of C6 in the interfacial layer between solid lipid nanoparticles (SLN) and aqueous medium. In the case of pre‐loading, C6 is homogenously distributed in emulsion droplets and expelled from the lipid matrix due to crystallization. Nanoemulsions distributed C6 in the liquid lipid matrix itself and cause a hypsochromic shift of fluorescence spectra. Larger surface areas of emulsion droplets due to smaller droplet sizes displayed more interaction of C6 with the aqueous phase as a bathochromic shoulder in fluorescence spectra. Measured fluorescence intensity was linearly dependent on light scattering of colloidal DDS of the same excipients. A simple method to evaluate the protective properties of DDS was presented and displayed that (i) nanoemulsions provide more protection compared with SLN and (ii) higher phospholipid concentration improve the protection within SLN.

Practical applications: In the development of colloidal DDS, it is important to identify the localization and distribution of a (model) drug in compartments within the disperse system. The simple approach by fluorescence spectroscopy presented in this study supplies information about the localization of drug substances with properties comparable with the fluorescent probe used. The results assist formulation development as a quick screening tool to elucidate (i) the localization of the probe, (ii) the microenvironment of the probe (e.g., differentiation of the physical state of the disperse phase), and (iii) the protection of the probe against damaging agents from the aqueous phase.

The fluorescent dye Coumarin 6 was applied as model drug in colloidal lipid drug delivery systems. Fluorescence spectroscopy proved able to identify the localization of the model compound, the physical state of the dispersed phase, and the protective potential of the DDS, especially dependent on phospholipid concentration.
Influence of Charging Current and Potential Drop on the Propagation of the Change in the Membrane Potential
Authors: Kushida Yuki , Shirai Osamu , Kitazumi Yuki , Kano Kenji
Published: July 2014

Propagation of a change in a potential difference between two aqueous phases (W1 and W2) across a membrane was examined by using three membrane cells (A, B and C). At first, the cell A was electrically connected with the cell B by controlling the ionic compositions. By changing the connection with the cell A from the cell B to the cell C indicating the different membrane potential, the change of the membrane potential was propagated. The delay and decrement of the propagation was observed by setting capacitors or resistors in the electric circuit.
Oxidative DNA damage in disease—Insights gained from base excision repair glycosylase‐deficient mouse models
Authors: Sampath Harini
Published: July 2014

Cellular components, including nucleic acids, are subject to oxidative damage. If left unrepaired, this damage can lead to multiple adverse cellular outcomes, including increased mutagenesis and cell death. The major pathway for repair of oxidative base lesions is the base excision repair pathway, catalyzed by DNA glycosylases with overlapping but distinct substrate specificities. To understand the role of these glycosylases in the initiation and progression of disease, several transgenic mouse models have been generated to carry a targeted deletion or overexpression of one or more glycosylases. This review summarizes some of the major findings from transgenic animal models of altered DNA glycosylase expression, especially as they relate to pathologies ranging from metabolic disease and cancer to inflammation and neuronal health. Environ. Mol. Mutagen. 55:689–703, 2014. © 2014 Wiley Periodicals, Inc.