bluuebunny/crossref_metadata_2025 huggingface dataset:
Back-junction back-contact n-type silicon solar cell with diffused boron emitter locally blocked by implanted phosphorus
Authors: Müller Ralph , Schrof Julian , Reichel Christian , Benick Jan , Hermle Martin
Published: September 2014

The highest energy conversion efficiencies in the field of silicon-based photovoltaics have been achieved with back-junction back-contact (BJBC) silicon solar cells by several companies and research groups. One of the most complex parts of this cell structure is the fabrication of the locally doped p- and n-type regions, both on the back side of the solar cell. In this work, we introduce a process sequence based on a synergistic use of ion implantation and furnace diffusion. This sequence enables the formation of all doped regions for a BJBC silicon solar cell in only three processing steps. We observed that implanted phosphorus can block the diffusion of boron atoms into the silicon substrate by nearly three orders of magnitude. Thus, locally implanted phosphorus can be used as an in-situ mask for a subsequent boron diffusion which simultaneously anneals the implanted phosphorus and forms the boron emitter. BJBC silicon solar cells produced with such an easy-to-fabricate process achieved conversion efficiencies of up to 21.7%. An open-circuit voltage of 674 mV and a fill factor of 80.6% prove that there is no significant recombination at the sharp transition between the highly doped emitter and the highly doped back surface field at the device level.
Label-free three-dimensional imaging of cell nucleus using third-harmonic generation microscopy
Authors: Lin Jian , Zheng Wei , Wang Zi , Huang Zhiwei
Published: September 2014

We report the implementation of the combined third-harmonic generation (THG) and two-photon excited fluorescence (TPEF) microscopy for label-free three-dimensional (3-D) imaging of cell nucleus morphological changes in liver tissue. THG imaging shows regular spherical shapes of normal hepatocytes nuclei with inner chromatin structures while revealing the condensation of chromatins and nuclear fragmentations in hepatocytes of diseased liver tissue. Colocalized THG and TPEF imaging provides complementary information of cell nuclei and cytoplasm in tissue. This work suggests that 3-D THG microscopy has the potential for quantitative analysis of nuclear morphology in cells at a submicron-resolution without the need for DNA staining.
Corrosion Study on Tantalum in Anhydrous Ethanol
Authors: Yang Hai-ping , Tang Mo-tang , Li Bi-hui
Published: September 2014

The corrosion behavior of tantalum in tetraethyl ammonium chloride (TEA) ethanol solutions was investigated using potentiodynamic polarization, cyclic voltammetry, and impedance techniques along with scanning electron microscopy (SEM). At the early stage of scanning, the current density in the cyclic voltammetry curves very slowly increased because of the presence of a thin oxide film on the electrode surface. Pitting corrosion then occurred as a result of the passivity breakdown caused by the aggressive attack of the Cl- anions. SEM images showed the growth process of the pits on the electrode surface. The pitting potential decreased with the increase in TEA concentration but increased with the increase in water concentration. The apparent activation energy of the electrochemical reaction was 36 kJ/mol. The impedance spectra exhibited two time constants for all the potentials. Both the passive layer resistance and the charge transfer resistance decreased with the increase in the potential.
Ethylene Trimerisation with Cr-PNP Catalysts: A Theoretical Benchmarking Study and Assessment of Catalyst Oxidation State
Authors: McGuinness David S. , Chan Bun , Britovsek George J. P. , Yates Brian F.
Published: September 2014

A model for the homogeneous Cr-PNP (PNP = diphosphinoamine) ethylene trimerisation and tetramerisation catalyst system has been studied theoretically, with the aim of identifying suitable density functional theory methods for treatment of this catalyst, and evaluating the likely oxidation and spin states of the active species. Benchmarking studies involving high-level treatment reveal the difficulty of accurately calculating the thermochemistry of this system, and suggest that local density functionals, such as M06L, probably provide the best option. Density functional theory modelling of catalyst activation and the first steps of oligomerisation up until 1-hexene formation appears to favour a CrI–CrIII mechanism, involving spin surface crossing from sextet to quartet states.
Potential rare earth free permanent magnet: interstitial boron doped FeCo
Authors: Khan Imran , Hong Jisang
Published: September 2014

Using the full potential linearized augmented plane wave method, we investigated the structural and the magnetic properties of boron doped FeCo. After fully relaxing the lattice structure, the interatomic distances between boron and Fe atoms were found to be greatly enhanced and the tetragonal distortion was realized due to this increased interatomic distance. Nonetheless, both the unit cell volume and the total magnetic moment of the tetragonally distorted FeCo structure were weakly suppressed compared with those of ideal bulk FeCo. We found a magnetocrystalline anisotropy constant of 0.8 MJ m−3 and this was mainly due to the tetragonal distortion induced by boron impurity, not from the hybridization effect with Fe or Co, because no essential change in the magnetocrystalline anisotropy constant was found even without boron impurity in the lattice distorted system. Additionally, the estimated maximum energy product and coercive field were 100 MGOe and 745 kA m−1, respectively. These results may imply that the interstitial boron doped FeCo can be used for a potential rare earth free permanent magnet although those values are likely to be suppressed in real samples due to micromagnetic factors.
Effect of Reversal of Neuromuscular Blockade with Sugammadex versus Usual Care on Bleeding Risk in a Randomized Study of Surgical Patients
Authors: Rahe-Meyer Niels , Fennema Hein , Schulman Sam , Klimscha Walter , Przemeck Michael , Blobner Manfred , Wulf Hinnerk , Speek Marcel , McCrary Sisk Christine , Williams-Herman Debora , Woo Tiffany , Szegedi Armin
Published: September 2014

Background:

Previous studies show a prolongation of activated partial thromboplastin time and prothrombin time in healthy volunteers after treatment with sugammadex. The authors investigated the effect of sugammadex on postsurgical bleeding and coagulation variables.

Methods:

This randomized, double-blind trial enrolled patients receiving thromboprophylaxis and undergoing hip or knee joint replacement or hip fracture surgery. Patients received sugammadex 4 mg/kg or usual care (neostigmine or spontaneous recovery) for reversal of rocuronium- or vecuronium-induced neuromuscular blockade. The Cochran–Mantel–Haenszel method, stratified by thromboprophylaxis and renal status, was used to estimate relative risk and 95% confidence interval (CI) of bleeding events with sugammadex versus usual care. Safety was further evaluated by prespecified endpoints and adverse event reporting.

Results:

Of 1,198 patients randomized, 1,184 were treated (sugammadex n = 596, usual care n = 588). Bleeding events within 24 h (classified by an independent, blinded Adjudication Committee) were reported in 17 (2.9%) sugammadex and 24 (4.1%) usual care patients (relative risk [95% CI], 0.70 [0.38 to 1.29]). Compared with usual care, increases of 5.5% in activated partial thromboplastin time (P < 0.001) and 3.0% in prothrombin time (P < 0.001) from baseline with sugammadex occurred 10 min after administration and resolved within 60 min. There were no significant differences between sugammadex and usual care for other blood loss measures (transfusion, 24-h drain volume, drop in hemoglobin, and anemia), or risk of venous thromboembolism, and no cases of anaphylaxis.

Conclusion:

Sugammadex produced limited, transient (<1 h) increases in activated partial thromboplastin time and prothrombin time but was not associated with increased risk of bleeding versus usual care.
Magnetic phase transitions and magnetic entropy in the
XY
antiferromagnetic pyrochlores (Er

1−
x

Y

x

)
2
Ti
2
O
7
Authors: Niven John F. , Johnson Michel B. , Bourque Alex , Murray Patrick J. , James David D. , Da̧bkowska Hanna A. , Gaulin Bruce D. , White Mary Anne
Published: September 2014

We present the results of experimental determination of the heat capacity of the pyrochlore Er
2
Ti
2
O
7
as a function of temperature (0.35–300 K) and magnetic field (up to 9 T), and for magnetically diluted solid solutions of the general formula (Er

1−
x

Y

x

)
2
Ti
2
O
7
(
x
≤0.471). On either doping or increase of magnetic field, or both, the Néel temperature first shifts to lower temperature until a critical point above which there is no well-defined transition but a Schottky-like anomaly associated with the splitting of the ground state Kramers doublet. By taking into account details of the lattice contribution to the heat capacity, we accurately isolate the magnetic contribution to the heat capacity and hence to the entropy. For pure Er
2
Ti
2
O
7
and for (Er

1−
x

Y

x

)
2
Ti
2
O
7
, the magnetic entropy as a function of temperature evolves with two plateaus: the first at

R
ln
⁡
2

, and the other at

R
ln
⁡
16

. When a very high magnetic field is applied, the first plateau is washed out. The influence of dilution at low values is similar to the increase of magnetic field, as we show by examination of the critical temperature versus critical field curve in reduced terms.
Quasi-periodic Wannier–Stark ladders from driven atomic Bloch oscillations
Authors: Artoni M. , La Rocca G. C. , Ferrari G.
Published: September 2014

Periodic Wannier–Stark ladder structures of the energy resonances associated with Bloch oscillations can be readily modified into quasi-periodic ones that exhibit peculiar self-similar effects. A compact theoretical description of the dynamics of driven Bloch oscillations is developed here within the quasi-momentum representation. We identify a rather viable scheme based on ultracold atomic wavepackets subject to gravity in a driven optical lattice potential where a self-similar scaling could be observed. Its feasibility in terms of realistic experimental parameters is also discussed.
On a consistent finite-strain plate theory based on three-dimensional energy principle
Authors: Dai Hui-Hui , Song Zilong
Published: September 2014

This paper derives a finite-strain plate theory consistent with the principle of stationary three-dimensional potential energy under general loadings with a fourth-order error. Starting from the three-dimensional nonlinear elasticity (with both geometrical and material nonlinearity) and by a series expansion, we deduce a vector plate equation with three unknowns, which exhibits the local force-balance structure. The success relies on using the three-dimensional field equations and bottom traction condition to derive exact recursion relations for the coefficients. Associated weak formulations are considered, leading to a two-dimensional virtual work principle. An alternative approach based on a two-dimensional truncated energy is also provided, which is less consistent than the first plate theory but has the advantage of the existence of a two-dimensional energy function. As an example, we consider the pure bending problem of a hyperelastic block. The comparison between the analytical plate solution and available exact one shows that the plate theory gives second-order correct results. Compared with existing plate theories, it appears that the present one has a number of advantages, including the consistency, order of correctness, generality of loadings, applicability to finite-strain problems and no involvement of non-physical quantities.
A constraint-free phase field model for ferromagnetic domain evolution
Authors: Yi Min , Xu Bai-Xiang
Published: September 2014

A continuum constraint-free phase field model is proposed to simulate the magnetic domain evolution in ferromagnetic materials. The model takes the polar and azimuthal angles (
ϑ
1
,
ϑ
2
), instead of the magnetization unit vector
m
(
m
1
,
m
2
,
m
3
), as the order parameters. In this way, the constraint on the magnetization magnitude can be exactly satisfied automatically, and no special numerical treatment on the phase field evolution is needed. The phase field model is developed from a thermodynamic framework which involves a configurational force system for
ϑ
1
and
ϑ
2
. A combination of the configurational force balance and the second law of thermodynamics leads to thermodynamically consistent constitutive relations and a generalized evolution equation for the order parameters (
ϑ
1
,
ϑ
2
). Beneficial from the constraint-free model, the three-dimensional finite-element implementation is straightforward, and the degrees of freedom are reduced by one. The model is shown to be capable of reproducing the damping-dependent switching dynamics, and the formation and evolution of domains and vortices in ferromagnetic materials under the external magnetic or mechanical loading. Particularly, the calculated out-of-plane component of magnetization in a vortex is verified by the corresponding experimental results, as well as the motion of the vortex under a magnetic field.
Spring phenology of ecological productivity contributes to the use of looped migration strategies by birds
Authors: La Sorte Frank A. , Fink Daniel , Hochachka Wesley M. , DeLong John P. , Kelling Steve
Published: September 2014

Migration is a common strategy used by birds that breed in seasonal environments. The patterns and determinants of migration routes, however, remain poorly understood. Recent empirical analyses have demonstrated that the locations of two North America migration flyways (eastern and western) shift seasonally, reflecting the influence of looped migration strategies. For the eastern but not western flyway, seasonal variation in atmospheric circulation has been identified as an explanation. Here, we test an alternative explanation based on the phenology of ecological productivity, which may be of greater relevance in western North America, where phenology is more broadly dictated by elevation. Migrants in the western flyway selected lower-elevation spring routes that were wetter, greener and more productive, and higher-elevation autumn routes that were less green and less productive, but probably more direct. Migrants in the eastern flyway showed little season variation but maintained associations with maximum regional greenness. Our findings suggest the annual phenology of ecological productivity is associated with en route timing in both flyways, and the spring phenology of ecological productivity contributes to the use of looped strategies in the western flyway. This fine-tuned spatial synchronization may be disrupted when changing climate induces a mismatch between food availability and needs.
Vultures acquire information on carcass location from scavenging eagles
Authors: Kane Adam , Jackson Andrew L. , Ogada Darcy L. , Monadjem Ara , McNally Luke
Published: September 2014

Vultures are recognized as the scroungers of the natural world, owing to their ecological role as obligate scavengers. While it is well known that vultures use intraspecific social information as they forage, the possibility of inter-guild social information transfer and the resulting multi-species social dilemmas has not been explored. Here, we use data on arrival times at carcasses to show that such social information transfer occurs, with raptors acting as producers of information and vultures acting as scroungers of information. We develop a game-theoretic model to show that competitive asymmetry, whereby vultures dominate raptors at carcasses, predicts this evolutionary outcome. We support this theoretical prediction using empirical data from competitive interactions at carcasses. Finally, we use an individual-based model to show that these producer–scrounger dynamics lead to vultures being vulnerable to declines in raptor populations. Our results show that social information transfer can lead to important non-trophic interactions among species and highlight important potential links among social evolution, community ecology and conservation biology. With vulture populations suffering global declines, our study underscores the importance of ecosystem-based management for these endangered keystone species.
The trophic vacuum and the evolution of complex life cycles in trophically transmitted helminths
Authors: Benesh Daniel P. , Chubb James C. , Parker Geoff A.
Published: September 2014

Parasitic worms (helminths) frequently have complex life cycles in which they are transmitted trophically between two or more successive hosts. Sexual reproduction often takes place in high trophic-level (TL) vertebrates, where parasites can grow to large sizes with high fecundity. Direct infection of high TL hosts, while advantageous, may be unachievable for parasites constrained to transmit trophically, because helminth propagules are unlikely to be ingested by large predators. Lack of niche overlap between propagule and definitive host (the trophic transmission vacuum) may explain the origin and/or maintenance of intermediate hosts, which overcome this transmission barrier. We show that nematodes infecting high TL definitive hosts tend to have more successive hosts in their life cycles. This relationship was modest, though, driven mainly by the minimum TL of hosts, suggesting that the shortest trophic chains leading to a host define the boundaries of the transmission vacuum. We also show that alternative modes of transmission, like host penetration, allow nematodes to reach high TLs without intermediate hosts. We suggest that widespread omnivory as well as parasite adaptations to increase transmission probably reduce, but do not eliminate, the barriers to the transmission of helminths through the food web.
The hawk–dove game in a sexually reproducing species explains a colourful polymorphism of an endangered bird
Authors: Kokko Hanna , Griffith Simon C. , Pryke Sarah R.
Published: September 2014

The hawk–dove game famously introduced strategic game theory thinking into biology and forms the basis of arguments for limited aggression in animal populations. However, aggressive ‘hawks’ and peaceful ‘doves’, with strategies inherited in a discrete manner, have never been documented in a real animal population. Thus, the applicability of game-theoretic arguments to real populations might be contested. Here, we show that the head-colour polymorphism of red and black Gouldian finches (
Erythrura gouldiae
) provides a real-life example. The aggressive red morph is behaviourally dominant and successfully invades black populations, but when red ‘hawks’ become too common, their fitness is severely compromised (via decreased parental ability). We also investigate the effects of real-life deviations, particularly sexual reproduction, from the simple original game, which assumed asexual reproduction. A protected polymorphism requires mate choice to be sufficiently assortative. Assortative mating is adaptive for individuals because of genetic incompatibilities affecting hybrid offspring fitness, but by allowing red ‘hawks’ to persist, it also leads to significantly reduced population sizes. Because reductions in male contributions to parental care are generally known to lead to lower population productivity in birds, we expect zero-sum competition to often have wide ranging population consequences.
Paenibacillus susongensis sp. nov., a mineral-weathering bacterium
Authors: Guo Xin-Qi , Gu Jia-Yu , Yu Ya-Jun , Zhang Wen-Bin , He Lin-Yan , Sheng Xia-Fang
Published: September 2014

A Gram-stain-positive, rod-shaped, endospore-forming, aerobic bacterial strain, designated M327T, was isolated from the weathered surfaces of rock (mica schist) from Susong, Anhui Province, PR China. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain M327T belonged to the genus

Paenibacillus

and was related most closely to

Paenibacillus terrigena

A35T (98.6 % similarity) and

Paenibacillus selenitireducens

ES3-24T (98.3 %). Strain M327T contained meso-diaminopimelic acid in the cell wall and MK-7 as the major menaquinone. The main fatty acids of strain M327T were anteiso-C15 : 0 and iso-C16 : 0. The polar lipid profile contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, three unknown aminophospholipids and an unknown lipid. The total DNA G+C content of strain M327T was 48.6 mol%. Based on the low level of DNA–DNA relatedness (ranging from 26.6 to 33.1 %) to these type strains of species of the genus

Paenibacillus

and unique phenotypic characteristics, it is suggested that strain M327T represents a novel species of the genus

Paenibacillus

, for which the name Paenibacillus susongensis sp. nov. is proposed. The type strain is M327T ( = CCTCC AB 2014058T = LMG 28236T = JCM 19951T).
Ascidiaceihabitans donghaensis gen. nov., sp. nov., isolated from the golden sea squirt Halocynthia aurantium
Authors: Kim Young-Ok , Park Sooyeon , Nam Bo-Hye , Lee Chu , Park Ja-Min , Kim Dong-Gyun , Yoon Jung-Hoon
Published: September 2014

A Gram-stain-negative, aerobic, non-motile and coccoid, ovoid or rod-shaped bacterial strain, designated RSS1-M3T, was isolated from a golden sea squirt (Halocynthia aurantium) collected from the East Sea, South Korea. Strain RSS1-M3T grew optimally at 30 °C, at pH 7.0–8.0 and in presence of 2.0 % (w/v) NaCl. Strain RSS1-M3T exhibited the highest 16S rRNA gene sequence similarity (96.55 %) to the type strain of

Pelagicola litoralis

. Neighbour-joining and maximum-likelihood phylogenetic trees based on 16S rRNA gene sequences revealed that strain RSS1-M3T clustered with the type strains, or proposed type strains, of

Planktotalea frisia

,

Pacificibacter maritimus

,

Roseovarius marinus

and

Halocynthiibacter namhaensis

, showing sequence similarity of 94.88–96.32 %. Strain RSS1-M3T contained Q-10 as the predominant ubiquinone and C18 : 1ω7c and C16 : 0 as the major fatty acids. The polar lipid profile of strain RSS1-M3T, containing phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, diphosphatidylglycerol, one unidentified aminolipid and one unidentified lipid as major components, could be distinguished from those of the phylogenetically related genera. The DNA G+C content of strain RSS1-M3T was 55.8 mol%. On the basis of the phylogenetic, chemotaxonomic and phenotypic properties, strain RSS1-M3T is considered to represent a novel species of a new genus within the class

Alphaproteobacteria

, for which the name Ascidiaceihabitans donghaensis gen. nov., sp. nov. is proposed. The type strain is RSS1-M3T ( = KCTC 42118T = CECT 8599T).
A new nodavirus is associated with covert mortality disease of shrimp
Authors: Zhang Qingli , Liu Qun , Liu Shuang , Yang Haolin , Liu Sun , Zhu Luoluo , Yang Bing , Jin Jiting , Ding Lixue , Wang Xiuhua , Liang Yan , Wang Qintao , Huang Jie
Published: September 2014

A new nodavirus, named covert mortality nodavirus (CMNV), is associated with covert mortality disease of shrimp which has caused serious loss in China since 2009. Histopathological examination of shrimp suffering the disease revealed coagulative necrosis of striated muscle similar to typical histopathology features of infectious myonecrosis virus (IMNV), Penaeus vannamei nodavirus (PvNV) and Macrobrachium rosenbergii nodavirus (MrNV). However, shrimp suffering this disease tested negative for IMNV, MrNV and PvNV by reverse transcription (RT)-PCR. Additionally, eosinophilic inclusions were found in epithelium of the tubules in the hepatopancreas and lymphoid organ, and mass karyopyknotic nuclei existed in the muscle and lymphoid organ. The tubular epithelium of the hepatopancreas showed significant atrophy. A cDNA library was constructed from total RNA of infected shrimp. Sequencing and alignment analysis showed that one clone with an 1185 bp insert (designated CMNV-7) shared 54 , 53  and 39 % identity with the amino acid sequences of RNA-dependent RNA polymerase from Flock House virus, black beetle virus and MrNV. The results of fluorescence in situ hybridization showed that the hepatopancreas, striated muscle and lymphoid organ were positively reacting tissues. The mean size of negative-stained virus particles was 32 nm. In addition, a nested RT-PCR assay was developed for CMNV, and the RT-PCR detection results revealed that Fenneropenaeus chinensis, Litopenaeus vannamei and Marsupenaeus japonicus suffering from this disease were CMNV-positive.
Extensive Decoupling of Metabolic Genes in Cancer
Authors: Reznik Ed , Sander Chris
Published: September 2014

Tumorigenesis involves, among other factors, the alteration of metabolic gene expression to support malignant, unrestrained proliferation. Here, we examine how the altered metabolism of cancer cells is reflected in changes in co-expression patterns of metabolic genes between normal and tumor tissues. Our emphasis on changes in the interactions of pairs of genes, rather than on the expression levels of individual genes, exposes changes in the activity of metabolic pathways which do not necessarily show clear patterns of over- or under-expression. We report the existence of key metabolic genes which act as hubs of differential co-expression, showing significantly different co-regulation patterns between normal and tumor states. Notably, we find that the extent of differential co-expression of a gene is only weakly correlated with its differential expression, suggesting that the two measures probe different features of metabolism. By leveraging our findings against existing pathway knowledge, we extract networks of functionally connected differentially co-expressed genes and the transcription factors which regulate them. Doing so, we identify a previously unreported network of dysregulated metabolic genes in clear cell renal cell carcinoma transcriptionally controlled by the transcription factor HNF4A. While HNF4A shows no significant differential expression, the co-expression HNF4A and several of its regulated target genes in normal tissue is completely abrogated in tumor tissue. Finally, we aggregate the results of differential co-expression analysis across seven distinct cancer types to identify pairs of metabolic genes which may be recurrently dysregulated. Among our results is a cluster of four genes, all located in the mitochondrial electron transport chain, which show significant loss of co-expression in tumor tissue, pointing to potential mitochondrial dysfunction in these tumor types.
Mitochondrial Alternative Oxidase Maintains Respiration and Preserves Photosynthetic Capacity during Moderate Drought in Nicotiana tabacum
Authors: Dahal Keshav , Wang Jia , Martyn Greg D. , Rahimy Farkhunda , Vanlerberghe Greg C.
Published: September 2014

The mitochondrial electron transport chain includes an alternative oxidase (AOX) that is hypothesized to aid photosynthetic metabolism, perhaps by acting as an additional electron sink for photogenerated reductant or by dampening the generation of reactive oxygen species. Gas exchange, chlorophyll fluorescence, photosystem I (PSI) absorbance, and biochemical and protein analyses were used to compare respiration and photosynthesis of Nicotiana tabacum ‘Petit Havana SR1’ wild-type plants with that of transgenic AOX knockdown (RNA interference) and overexpression lines, under both well-watered and moderate drought-stressed conditions. During drought, AOX knockdown lines displayed a lower rate of respiration in the light than the wild type, as confirmed by two independent methods. Furthermore, CO2 and light response curves indicated a nonstomatal limitation of photosynthesis in the knockdowns during drought, relative to the wild type. Also relative to the wild type, the knockdowns under drought maintained PSI and PSII in a more reduced redox state, showed greater regulated nonphotochemical energy quenching by PSII, and displayed a higher relative rate of cyclic electron transport around PSI. The origin of these differences may lie in the chloroplast ATP synthase amount, which declined dramatically in the knockdowns in response to drought. None of these effects were seen in plants overexpressing AOX. The results show that AOX is necessary to maintain mitochondrial respiration during moderate drought. In its absence, respiration rate slows and the lack of this electron sink feeds back on the photosynthetic apparatus, resulting in a loss of chloroplast ATP synthase that then limits photosynthetic capacity.
Seismic attenuation and velocity dispersion in fractured rocks: The role played by fracture contact areas
Authors: Rubino J. Germán , Müller Tobias M. , Milani Marco , Holliger Klaus
Published: September 2014

The presence of fractures in fluid‐saturated porous rocks is usually associated with strong seismic P‐wave attenuation and velocity dispersion. This energy dissipation can be caused by oscillatory wave‐induced fluid pressure diffusion between the fractures and the host rock, an intrinsic attenuation mechanism generally referred to as wave‐induced fluid flow. Geological observations suggest that fracture surfaces are highly irregular at the millimetre and sub‐millimetre scale, which finds its expression in geometrical and mechanical complexities of the contact area between the fracture faces. It is well known that contact areas strongly affect the overall mechanical fracture properties. However, existing models for seismic attenuation and velocity dispersion in fractured rocks neglect this complexity. In this work, we explore the effects of fracture contact areas on seismic P‐wave attenuation and velocity dispersion using oscillatory relaxation simulations based on quasi‐static poroelastic equations. We verify that the geometrical and mechanical details of fracture contact areas have a strong impact on seismic signatures. In addition, our numerical approach allows us to quantify the vertical solid displacement jump across fractures, the key quantity in the linear slip theory. We find that the displacement jump is strongly affected by the geometrical details of the fracture contact area and, due to the oscillatory fluid pressure diffusion process, is complex‐valued and frequency‐dependent. By using laboratory measurements of stress‐induced changes in the fracture contact area, we relate seismic attenuation and dispersion to the effective stress. The corresponding results do indeed indicate that seismic attenuation and phase velocity may constitute useful attributes to constrain the effective stress. Alternatively, knowledge of the effective stress may help to identify the regions in which wave induced fluid flow is expected to be the dominant attenuation mechanism.
The 5th National Audit Project (NAP5) on accidental awareness during general anaesthesia: summary of main findings and risk factors
Authors: Pandit J. J. , Andrade J. , Bogod D. G. , Hitchman J. M. , Jonker W. R. , Lucas N. , Mackay J. H. , Nimmo A. F. , O'Connor K. , O'Sullivan E. P. , Paul R. G. , Palmer J. H. MacG. , Plaat F. , Radcliffe J. J. , Sury M. R. J. , Torevell H. E. , Wang M. , Hainsworth J. , Cook T. M. ,   the Royal College of Anaesthetists and the Association of Anaesthetists of Great Britain and Ireland
Published: September 2014

We present the main findings of the 5th National Audit Project on accidental awareness during general anaesthesia. Incidences were estimated using reports of accidental awareness as the numerator, and a parallel national anaesthetic activity survey to provide denominator data. The incidence of certain/probable and possible accidental awareness cases was ~1:19 600 anaesthetics (95% CI 1:16 700–23 450). However, there was considerable variation across subtypes of techniques or subspecialties. The incidence with neuromuscular blockade was ~1:8200 (1:7030–9700), and without it was ~1:135 900 (1:78 600–299 000). The cases of accidental awareness during general anaesthesia reported to 5th National Audit Project were overwhelmingly cases of unintended awareness during neuromuscular blockade. The incidence of accidental awareness during caesarean section was ~1:670 (1:380–1300). Two thirds (82, 66%) of cases of accidental awareness experiences arose in the dynamic phases of anaesthesia, namely induction of and emergence from anaesthesia. During induction of anaesthesia, contributory factors included: use of thiopental; rapid sequence induction; obesity; difficult airway management; neuromuscular blockade; and interruptions of anaesthetic delivery during movement from anaesthetic room to theatre. During emergence from anaesthesia, residual paralysis was perceived by patients as accidental awareness, and commonly related to a failure to ensure full return of motor capacity. One third (43, 33%) of accidental awareness events arose during the maintenance phase of anaesthesia, most due to problems at induction or towards the end of anaesthesia. Factors increasing the risk of accidental awareness included: female sex; age (younger adults, but not children); obesity; anaesthetist seniority (junior trainees); previous awareness; out‐of‐hours operating; emergencies; type of surgery (obstetric, cardiac, thoracic); and use of neuromuscular blockade. The following factors were not risk factors for accidental awareness: ASA physical status; race; and use or omission of nitrous oxide. We recommend that an anaesthetic checklist, to be an integral part of the World Health Organization Safer Surgery checklist, is introduced as an aid to preventing accidental awareness. This paper is a shortened version describing the main findings from 5th National Audit Project – the full report can be found at http://www.nationalauditprojects.org.uk/NAP5_home#pt.
The 5th National Audit Project (NAP5) on accidental awareness during general anaesthesia: patient experiences, human factors, sedation, consent and medicolegal issues
Authors: Cook T. M. , Andrade J. , Bogod D. G. , Hitchman J. M. , Jonker W. R. , Lucas N. , Mackay J. H. , Nimmo A. F. , O'Connor K. , O'Sullivan E. P. , Paul R. G. , Palmer J. H. MacG. , Plaat F. , Radcliffe J. J. , Sury M. R. J. , Torevell H. E. , Wang M. , Hainsworth J. , Pandit J. J. ,   the Royal College of Anaesthetists and the Association of Anaesthetists of Great Britain and Ireland
Published: September 2014

The 5th National Audit Project of the Royal College of Anaesthetists and the Association of Anaesthetists of Great Britain and Ireland into accidental awareness during general anaesthesia yielded data related to psychological aspects from the patient, and the anaesthetist, perspectives; patients’ experiences ranged from isolated auditory or tactile sensations to complete awareness. A striking finding was that 75% of experiences were for < 5 min, yet 51% of patients (95% CI 43–60%) experienced distress and 41% (95% CI 33–50%) suffered longer‐term adverse effect. Distress and longer‐term harm occurred across the full range of experiences but were particularly likely when the patient experienced paralysis (with or without pain). The patient's interpretation of what is happening at the time of the awareness seemed central to later impact; explanation and reassurance during suspected accidental awareness during general anaesthesia or at the time of report seemed beneficial. Quality of care before the event was judged good in 26%, poor in 39% and mixed in 31%. Three quarters of cases of accidental awareness during general anaesthesia (75%) were judged preventable. In 12% of cases of accidental awareness during general anaesthesia, care was judged good and the episode not preventable. The contributory and human factors in the genesis of the majority of cases of accidental awareness during general anaesthesia included medication, patient and education/training. The findings have implications for national guidance, institutional organisation and individual practice. The incidence of ‘accidental awareness’ during sedation (~1:15 000) was similar to that during general anaesthesia (~1:19 000). The project raises significant issues about information giving and consent for both sedation and anaesthesia. We propose a novel approach to describing sedation from the patient's perspective which could be used in communication and consent. Eight (6%) of the patients had resorted to legal action (12, 11%, to formal complaint) at the time of reporting. The 5th National Audit Project methodology provides a standardised template that might usefully inform the investigation of claims or serious incidents related to accidental awareness during general anaesthesia.
PTFE Grafts Versus Tunneled Cuffed Catheters for Hemodialysis: Which Is the Second Choice When Arteriovenous Fistula Is Not Feasible?
Authors: Donati Gabriele , Cianciolo Giuseppe , Mauro Raffaella , Rucci Paola , Scrivo Anna , Marchetti Antonio , Giampalma Emanuela , Golfieri Rita , Panicali Laura , Iorio Mario , Stella Andrea , La Manna Gaetano , Stefoni Sergio
Published: September 2014

Vascular access‐related complications are still one of the leading causes of morbidity in hemodialysis patients. The aim of this study was to compare polytetrafluoroethylene (PTFE) grafts versus tunneled cuffed permanent catheters (TCCs) in terms of vascular access and patients' survival. An observational study was carried out with a 2‐year follow‐up. Eighty‐seven chronic hemodialysis patients were enrolled: 31 with a PTFE graft as vascular access for hemodialysis versus 56 with a TCC. Patients' mean age was 63.8 ± 14.6 (grafts) versus 73.5 ± 11.3 years (TCCs), P = 0.001. Significantly more patients with TCC had atrial fibrillation than patients with grafts (30.3% versus 6.5%, P = 0.01). In an unadjusted Kaplan–Meier analysis, median TCC survival at 24 months was 5.4 months longer than that of PTFE grafts but not significantly (log‐rank test = 1.3, P = ns). In a Cox regression analysis adjusted for age, gender, number of previous vascular accesses, diabetes, atrial fibrillation, smoking, and any complication, this lack of significant difference in survival of the vascular access between TCC and PTFE groups was confirmed and diabetes proved to be an independent risk factor for the survival of both vascular accesses considered (P = 0.02). In an unadjusted Kaplan–Meier analysis, a higher mortality was found in the TCC group than in the PTFE group at 24 months (log‐rank test = 10.07, P < 0.01). The adjusted Cox regression analysis showed that patients with TCC had a 3.2 times higher risk of death than patients with PTFE grafts. When an arteriovenous fistula (AVF) is not possible, PTFE grafts can be considered the vascular access of second choice, whereas TCCs can be used when an AVF or PTFE graft are not feasible or as a bridge to AVF or PTFE graft creation.
Activation of the brain melanocortin system is required for leptin‐induced modulation of chemorespiratory function
Authors: Bassi M. , Nakamura N. B. , Furuya W. I. , Colombari D. S. A. , Menani J. V. , do Carmo J. M. , da Silva A. A. , Hall J. E. , Colombari E.
Published: September 2014

Melanocortin receptors (MC3/4R) mediate most of the metabolic and cardiovascular actions of leptin.

Aim

Here, we tested if MC4R also contributes to leptin's effects on respiratory function.

Methods

After control measurements, male Holtzman rats received daily microinjections of leptin, SHU9119 (MC3/4R antagonist) or SHU9119 combined with leptin infused into the brain lateral ventricle for 7 days. On the 6th day of treatment, tidal volume (VT), respiratory frequency (fR) and pulmonary ventilation (VE) were measured by whole‐body plethysmography during normocapnia or hypercapnia (7% CO2). Baseline mean arterial pressure (MAP), heart rate (HR) and metabolic rate were also measured. VE, VT and fR were also measured in mice with leptin receptor deletion in the entire central nervous system (LepR/Nestin‐cre) or only in proopiomelanocortin neurones (LepR/POMC‐cre) and in MC4R knockout (MC4R−/−) and wild‐type mice.

Results

Leptin (5 μg day−1) reduced body weight (~17%) and increased ventilatory response to hypercapnia, whereas SHU9119 (0.6 nmol day−1) increased body weight (~18%) and reduced ventilatory responses compared with control‐PBS group (Lep: 2119 ± 90 mL min−1 kg−1 and SHU9119: 997 ± 67 mL min−1 kg−1, vs. PBS: 1379 ± 91 mL min−1 kg−1). MAP increased after leptin treatment (130 ± 2 mmHg) compared to PBS (106 ± 3 mmHg) or SHU9119 alone (109 ± 3 mmHg). SHU9119 prevented the effects of leptin on body weight, MAP (102 ± 3 mmHg) and ventilatory response to hypercapnia (1391 ± 137 mL min−1 kg−1). The ventilatory response to hypercapnia was attenuated in the LepR/Nestin‐cre, LepR/POMC‐cre and MC4R−/− mice.

Conclusion

These results suggest that central MC4R mediate the effects of leptin on respiratory response to hypercapnia.
Intravenous Lipid Emulsion Given to Volunteers does not Affect Symptoms of Lidocaine Brain Toxicity
Authors: Heinonen Juho A. , Litonius Erik , Salmi Tapani , Haasio Juhani , Tarkkila Pekka , Backman Janne T. , Rosenberg Per H.
Published: September 2014

Intravenous lipid emulsion has been suggested as treatment for local anaesthetic toxicity, but the exact mechanism of action is still uncertain. Controlled studies on the effect of lipid emulsion on toxic doses of local anaesthetics have not been performed in man. In randomized, subject‐blinded and two‐phase cross‐over fashion, eight healthy volunteers were given a 1.5 ml/kg bolus of 20% Intralipid® (200 mg/ml) or Ringer's acetate solution intravenously, followed by a rapid injection of lidocaine 1.0 mg/kg. Then, the same solution as in the bolus was infused at a rate of 0.25 ml/kg/min. for 30 min. Electroencephalography (EEG) was recorded, and 5 min. after lidocaine injection, the volunteers were asked to report subjective symptoms. Total and un‐entrapped lidocaine plasma concentrations were measured from venous blood samples. EEG band power changes (delta, alpha and beta) after the lidocaine bolus were similar during lipid and during Ringer infusion. There were no differences between infusions in the subjective symptoms of central nervous system toxicity. Lidocaine was only minimally entrapped in the plasma by lipid emulsion, but the mean un‐entrapped lidocaine area under concentration–time curve from 0 to 30 min. was clearly smaller during lipid than Ringer infusion (16.4 versus 21.3 mg × min/l, p = 0.044). Intravenous lipid emulsion did not influence subjective toxicity symptoms nor affect the EEG changes caused by lidocaine.
Palmitoylethanolamide, a naturally occurring lipid, is an orally effective intestinal anti‐inflammatory agent
Authors: Borrelli Francesca , Romano Barbara , Petrosino Stefania , Pagano Ester , Capasso Raffaele , Coppola Diana , Battista Giovanni , Orlando Pierangelo , Di Marzo Vincenzo , Izzo Angelo A
Published: September 2014

Background and Purpose

Palmitoylethanolamide (PEA) acts via several targets, including cannabinoid CB1 and CB2 receptors, transient receptor potential vanilloid type‐1 (TRPV1) ion channels, peroxisome proliferator‐activated receptor alpha (PPAR α) and orphan G protein‐coupled receptor 55 (GRR55), all involved in the control of intestinal inflammation. Here, we investigated the effect of PEA in a murine model of colitis.

Experimental Approach

Colitis was induced in mice by intracolonic administration of dinitrobenzenesulfonic acid (DNBS). Inflammation was assessed by evaluating inflammatory markers/parameters and by histology; intestinal permeability by a fluorescent method; colonic cell proliferation by immunohistochemistry; PEA and endocannabinoid levels by liquid chromatography mass spectrometry; receptor and enzyme mRNA expression by quantitative RT‐PCR.

Key Results

DNBS administration caused inflammatory damage, increased colonic levels of PEA and endocannabinoids, down‐regulation of mRNA for TRPV1 and GPR55 but no changes in mRNA for CB1, CB2 and PPARα. Exogenous PEA (i.p. and/or p.o., 1 mg·kg−1) attenuated inflammation and intestinal permeability, stimulated colonic cell proliferation, and increased colonic TRPV1 and CB1 receptor expression. The anti‐inflammatory effect of PEA was attenuated or abolished by CB2 receptor, GPR55 or PPARα antagonists and further increased by the TRPV1 antagonist capsazepine.

Conclusions and Implications

PEA improves murine experimental colitis, the effect being mediated by CB2 receptors, GPR55 and PPARα, and modulated by TRPV1 channels.
The Many Meanings of the Only Christ
Authors: Trelstad Marit
Published: September 2014

The intertwining of reflection about Christ and personal experience of Jesus has been at the heart of the matter from the start of the Reformation. Luther's Christology unites the transcendent and the intimate; it is Christ alone, Solus Christus, who mediates God's presence and promise to the world. This becomes one of the “solas” of the Reformation and the one to which this volume of Dialog is dedicated. This introduction considers the variety of ways theology has described the primary experience of Christ; we will consider how Christ has been theologically presented in terms of love, liberation, creativity, co‐sufferer, and holy presence. In addition, within the last century, one can see Christologies taking on universal or particular forms. The universal approach sees Christ in, with and under all the world, whereas the more “particular” forms connect to the singularity of Christ or Jesus as the sole locus of revelation of God in history or today. This introduction also explores the contemporary debate about the meaning of the cross and atonement in relation to the understanding of Christ as savior.
Christ as Chrism, Christ Given Away
Authors: Mercedes Anna
Published: September 2014

This article develops the concept of Christ not as static body but as chrism for bodies. Christ as chrism travels in the matrix of relationality, on a vector toward the benefit of others. Conceptualizing christ as chrism potentially avoids both exclusionary and colonizing tendencies in Christian polity, and frames a Christian ethics that, while vulnerable and risky, marks the sanctity of the one giving Christ away.
Synergistic metabolic benefits of an exenatide analogue and cholecystokinin in diet‐induced obese and leptin‐deficient rodents
Authors: Trevaskis J. L. , Sun C. , Athanacio J. , D'Souza L. , Samant M. , Tatarkiewicz K. , Griffin P. S. , Wittmer C. , Wang Y. , Teng C.‐H. , Forood B. , Parkes D. G. , Roth J. D.
Published: September 2014

Aim

To test the impact of cholecystokinin (CCK) plus either amylin or a glucagon‐like peptide‐1 receptor (GLP‐1R) agonist on metabolic variables in diet‐induced obese (DIO) rodents.

Methods

A stabilized acetylated version of CCK‐8 (Ac‐Y*‐CCK‐8), selective CCK1 receptor (CCK1R) or CCK2 receptor (CCK2R) agonists, amylin or the GLP‐1R agonist and exenatide analogue AC3174 were administered in select combinations via continuous subcutaneous infusion to DIO rats for 14 days, or Lepob/Lepob mice for 28 days, and metabolic variables were assessed.

Results

Combined administration of Ac‐Y*‐CCK‐8 with either amylin or AC3174 induced greater than additive weight loss in DIO rats, with the overall magnitude of effect being greater with AC3174 + Ac‐Y*‐CCK‐8 treatment. Co‐infusion of AC3174 with a specific CCK1R agonist, but not a CCK2R agonist, recapitulated the weight loss mediated by AC3174 + Ac‐Y*‐CCK‐8 in DIO rats, suggesting that synergy is mediated by CCK1R activation. In a 4 × 4 full‐factorial response surface methodology study in DIO rats, a synergistic interaction between AC3174 and the CCK1R‐selective agonist on body weight and food intake was noted. Co‐administration of AC3174 and the CCK1R‐selective agonist to obese diabetic Lepob/Lepob mice elicited a significantly greater reduction in percentage of glycated haemoglobin and food intake relative to the sum effects of monotherapy groups.

Conclusions

The anti‐obesity and antidiabetic potential of combined GLP‐1R and CCK1R agonism is an approach that warrants further investigation.