bluuebunny/crossref_metadata_2025 huggingface dataset:
Immune cells regulate VEGF signalling via release of VEGF and antagonistic soluble VEGF receptor-1
Authors: Hoeres T , Wilhelm M , Smetak M , Holzmann E , Schulze-Tanzil G , Birkmann J
Published: December 2017

Vascular endothelial growth factor (VEGF) is an important regulator of physiological and pathological angiogenesis. Besides malignant and stromal cells, local immune cells shape VEGF signalling in the tumour microenvironment. Aminobisphosphonates such as zoledronic acid (Zol) are drugs known to inhibit osteoclast activity and bone resorption, but also have immunomodulatory and anti-tumour effects. These properties have been linked previously to the down-regulation of VEGF and interference with tumour neo-angiogenesis. It was therefore surprising to find that treatment with Zol in combination with low-dose interleukin (IL)-2 increased serum VEGF levels in cancer patients. In this study we aimed to characterize the effect of Zol and IL-2 on VEGF signalling of blood-derived immune cells in vitro. Upon stimulation with IL-2, T cells and natural killer (NK) cells increase production of VEGF consecutively to the release of proinflammatory interferon (IFN)-γ, and Zol accelerates this response specifically in γδ T cells. VEGF can, in turn, be antagonized by soluble VEGF receptor (sVEGFR)-1, which is released depending on stimulatory conditions and the presence of monocytes. Additionally, malignant cells represented by leukaemia and lymphoma cell lines produce VEGF and some release sVEGFR-1 simultaneously. Our findings indicate a mechanism by which the VEGF and the sVEGFR-1 production by immune cells regulates local VEGF signalling. Therefore, immunotherapeutic interventions may enable both pro- as well as anti-tumour effects via immune cell-mediated alterations of VEGF homeostasis.
Contrasting above‐ and belowground organic matter decomposition and carbon and nitrogen dynamics in response to warming in High Arctic tundra
Authors: Blok Daan , Faucherre Samuel , Banyasz Imre , Rinnan Riikka , Michelsen Anders , Elberling Bo
Published: December 2017

Tundra regions are projected to warm rapidly during the coming decades. The tundra biome holds the largest terrestrial carbon pool, largely contained in frozen permafrost soils. With warming, these permafrost soils may thaw and become available for microbial decomposition, potentially providing a positive feedback to global warming. Warming may directly stimulate microbial metabolism but may also indirectly stimulate organic matter turnover through increased plant productivity by soil priming from root exudates and accelerated litter turnover rates. Here, we assess the impacts of experimental warming on turnover rates of leaf litter, active layer soil and thawed permafrost sediment in two high‐arctic tundra heath sites in NE‐Greenland, either dominated by evergreen or deciduous shrubs. We incubated shrub leaf litter on the surface of control and warmed plots for 1 and 2 years. Active layer soil was collected from the plots to assess the effects of 8 years of field warming on soil carbon stocks. Finally, we incubated open cores filled with newly thawed permafrost soil for 2 years in the active layer of the same plots. After field incubation, we measured basal respiration rates of recovered thawed permafrost cores in the lab. Warming significantly reduced litter mass loss by 26% after 1 year incubation, but differences in litter mass loss among treatments disappeared after 2 years incubation. Warming also reduced litter nitrogen mineralization and decreased the litter carbon to nitrogen ratio. Active layer soil carbon stocks were reduced 15% by warming, while soil dissolved nitrogen was reduced by half in warmed plots. Warming had a positive legacy effect on carbon turnover rates in thawed permafrost cores, with 10% higher respiration rates measured in cores from warmed plots. These results demonstrate that warming may have contrasting effects on above‐ and belowground tundra carbon turnover, possibly governed by microbial resource availability.
Letter to the author from Editor‐in‐Chief seeking clarifications
Authors: Sonuga‐Barke Edmund
Published: December 2017

Read the full article at doi: 10.1111/jcpp.12652
Interpersonal Acceptance–Rejection Theory: Application to Lesbian, Gay, and Bisexual Persons
Authors: Fuller Kimberly A.
Published: December 2017

Many researchers have focused on parents' responses to their child's sexual identity. Although this type of research has been conducted over the past 2 decades on the impact of coming out, there is not a consistently implemented theoretical orientation used across lesbian, gay, and bisexual (LGB) literature for describing and understanding the implications of coming out. However, interpersonal acceptance–rejection theory (IPARTheory) can be used as a framework to describe the experiences of acceptance–rejection LGB people face after disclosure. Many of the constructs outlined in IPARTheory are present throughout the literature on LGB coming‐out experiences, but a more thorough understanding of the implications of LGB parental acceptance–rejection across the life span is needed, especially as it affects psychological well‐being and adult relationship development. Several aspects of IPARTheory that need to be developed further to encompass the ways LGB people experience parental acceptance–rejection are discussed. Further, suggestions are made to better measure the specific types of acceptance–rejection faced by LGB people when they come out.
Three‐Dimensional Static Articulation Accuracy of Virtual Models – Part I: System Trueness and Precision
Authors: Yee Sophia Hui Xin , Esguerra Roxanna Jean , Chew Amelia Anya Qin'An , Wong Keng Mun , Tan Keson Beng Choon
Published: December 2017

Purpose

To evaluate the 3D static articulation accuracy of 3 model scanner‐CAD systems (Ceramill Map400 [AG], inEos X5 [SIR], Scanner S600 Arti [ZKN]) using a coordinate measuring machine (CMM). Trueness and precision for each system will be reported in Part I.

Materials and Methods

The master model simulated a single crown opposing a 3‐unit fixed dental prosthesis. Five mounted stone cast sets were prepared, and one set was randomly selected. Reference values were obtained by measuring interarch and interocclusal reference features with the CMM. The stone cast set was scanned 5 times consecutively and articulated virtually with each system (3 test groups, n = 5). STL files of the virtual models were measured with CMM software. dRR, dRC, and dRL, represented interarch global distortions at right, central, and left sides, respectively, while dRM, dXM, dYM, and dZM represented interocclusal global and linear distortions between preparations.

Results

For trueness values, mean interarch global distortions ranged from 13.1 to 40.3 μm for dRR, –199.0 to –48.1 μm for dRC, and –114.1 to –47.7 μm for dRL. Mean percentage error of interarch distortion did not exceed 0.6%. Mean interocclusal distortions ranged from 16.0 to 117.0 μm for dRM, ‐33.1 to 101.3 μm for dXM, 32.9 to 49.9 μm for dYM and –32.0 to 133.1 μm for dZM. ANOVA of trueness found statistically significant differences for dRC, dRL, dRM, dXM, and dZM. For precision values, absolute mean difference between the 10 superimposition combinations ranged from 25.3 to 91.0 μm for dRR, 21.5 to 85.5 μm for dRC, 24.8 to 70.0 μm for dRL. Absolute mean difference ranged from 49.9 to 66.1 μm for dRM, 20.7 to 92.1 μm for dXM, 86.8 to 96.0 μm for dYM, and 36.5 to 100.0 μm for dZM. ANOVA of precision of all test groups found statistically significant differences for dRR, dRC, dRL, dXM and dZM, and the SIR group was the least precise.

Conclusion

The overall interarch global distortion of all three model scanner‐CAD systems was low and did not exceed 0.6%. Variations in scanner technology, virtual articulation algorithm, and use of physical articulators contributed to the differences in distortion observed among all three groups.
The Effect of Surface Treatment on Shear Bond Strength between Y‐TZP and Veneer Ceramic: A Systematic Review and Meta‐Analysis
Authors: de Mello Caroline Cantieri , Bitencourt Sandro Basso , dos Santos Daniela Micheline , Pesqueira Aldiéris Alves , Pellizzer Eduardo Piza , Goiato Marcelo Coelho
Published: December 2017

Purpose

The objective of this systematic review with meta‐analysis was to evaluate surface treatment in yttria‐stabilized tetragonal zirconia polycrystal ceramic (Y‐TZP) on the shear bond strength (SBS) values between Y‐TZP (core ceramic) and veneer ceramic, compared to untreated specimens.

Materials and Methods

This review was registered at PROSPERO platform under the number CRD42016036493. The systematic review of the extracted publications was performed to compare the effect of surface treatment on SBS between Y‐TZP ceramic and veneering ceramic. A comprehensive review of the literature from the earliest available dates through January 2017 was performed in the PubMed/Medline, Embase, Scopus, and Cochrane Library databases.

Results

A total of 15 studies were identified for the inclusion of data, with only in vitro studies. A random‐effect model found statistically significant differences between untreated and treated surfaces of Y‐TZP (p < 0.00001; MD: 2.84; 95% CI: 2.19 to 3.49). In another analysis, a random‐effect model found statistically significant differences between the groups that only performed the associations of treatments and control group (p < 0.00001; MD: 3.19; 95% CI: 2.11 to 4.28).

Conclusions

Surface treatment in Y‐TZP improved the values of SBS between the Y‐TZP and veneer ceramic. The associations between two or more treatments also showed positive effect on the bond strength due the cumulative effect of the treatments.
Porcine intestinal yeast species, Kazachstania slooffiae, a new potential protein source with favourable amino acid composition for animals
Authors: Urubschurov V. , Büsing K. , Souffrant W.‐B. , Schauer N. , Zeyner A.
Published: December 2017

There is little information about Kazachstania slooffiae which dominates among other yeasts in the pigs’ intestine. Therefore, the aims of this study were to characterise the yeast cell contents and to investigate which nitrogen sources, organic acids and alcohols may be utilised or produced by this species. The results showed that, K. slooffiae could use urea, ammonium sulphate, peptides and single amino acids and produce thereby ethanol and formic acid. However, this yeast did not metabolise amino acids, lactic, butyric, propionic and acetic acids as sole carbon source. Using a global metabolite profiling approach employing gas chromatography and high‐resolution liquid chromatography mass spectrometry, was found that the amount of peptides and dehydroascorbic acid considerably increased in the fermentation residues after yeast cultivation. It is noteworthy that the cells of K. slooffiae had higher contents of nitrogen and total amino acids (especially lysine) than the cells of nutritional yeast (Saccharomyces cerevisiae). This study indicates that due to potential production of peptides and formic acid in the intestinal tract, K. slooffiae might have an impact on the gut health. Moreover, from a nutritional standpoint, the cells of this yeast can be a good source of protein with useful amino acid composition for animal.
Experiences of Singapore nurses as second victims: A qualitative study
Authors: Chan Shi Teng , Khong Betty Peck Chui , Pei Lin Tan Lynnette , He Hong‐Gu , Wang Wenru
Published: December 2017

Nurses, like other healthcare professionals, such as physicians, pharmacists, and therapists, are susceptible to unanticipated patient harm, in which they suffer as second victims due to the immense personal and professional impact from the adverse event. The aim of the present study was to explore the psychological responses, coping strategies, and support needs of Singapore nurses as second victims of adverse events. A descriptive qualitative study was adopted. Eight participants (6 women and 2 men) who had been involved in an adverse event were interviewed and audio‐recorded. Thematic analysis was performed to analyze the data. Seven themes emerged from the thematic analysis: responding psychologically after the event, feeling others’ prejudice, having intrusive thoughts, drawing valuable lessons from the event, coping to recover after the event, taking responsibility for the mistakes made, and finding self‐identity. The harmful effects of adverse events on nurses are long lasting. Second‐victim nurses adopted various coping strategies to recover. The findings from the present study will guide the development of effective second‐victim support programs.
Mobility and resource use influence the occurrence of pollinating insects in restored seminatural grassland fragments
Authors: Öckinger Erik , Winsa Marie , Roberts Stuart P. M. , Bommarco Riccardo
Published: December 2017

After habitat restoration, species need to recolonize from existing populations. The ability of species to recolonize restored habitats likely depends on their traits. This study aimed to test if species traits and isolation from source habitat can explain the presence of insects in restored grasslands. We surveyed the occurrence of hoverflies and bees in 14 restored seminatural pastures as well as in intact seminatural grasslands in the surrounding landscape. We tested how connectivity, time since restoration, and species traits influence if species that are present in the surrounding landscape also occur in restored pastures. Solitary bee species present in the landscape were less likely to occur in restored pastures compared to bumblebees and hoverflies. The occurrence of bumblebees, but not solitary bees or hoverflies, decreased with time since restoration. The occurrence of solitary bees increased but the occurrence of hoverflies decreased with high connectivity. Migratory hoverflies were more likely to occur in restored pastures than nonmigratory hoverflies, especially in pastures with low connectivity. Among both bumblebees and solitary bees, the occurrence was influenced by nesting traits, with the lowest occurrence of parasitic species and of species digging nests in the ground. The subset of the landscape's species pool that occurs in restored pastures has a contrasting set of traits compared with species in intact source habitats. Both mobility and resource use act as filters that influence the assembly of pollinator communities after restoration. A full recovery of pollinator communities is more likely if source populations are available nearby.
Dating palaeo‐seismic faulting in the Taiwan Mountain Belt
Authors: Chen Chih‐Tung , Wu Chieh‐Yu , Lo Ching‐Hua , Chu Hao‐Tsu , Yui Tzen‐Fu
Published: December 2017

In‐situ 40Ar/39Ar laser microprobe dating was carried out on the Hoping pseudotachylite from a mylonite‐fault zone in the metamorphosed basement complex of the active Taiwan Mountain Belt to determine the timing of the responsible earthquake(s). The dating results, distributed from 3.2 to 1.6 Ma with errors ranging from 0.2 to 1.1 Ma, were derived from a combination of two Ar isotopic system end‐members with inverse isochron ages of 1.55 ± 0.05 and 2.87 ± 0.07 Ma, respectively. Petrographical observations reveal fault melt containing ultracataclasites, therefore the older inverse isochron end‐member may be attributed to the relic wall rock Ar isotopic system contained in micro‐breccia. Without significant Ar loss expected, the ~1.6 Ma for the young end‐member defines the exact time of the pseudotachylite formation. Seismic faulting therefore occurred during basement rock exhumation in the Taiwanese hinterland.
Detection and genetic characterization of diverse Bartonella genotypes in the small mammals of Singapore
Authors: Neves E. S. , Mendenhall I. H. , Borthwick S. A. , Su Y. C. F. , Smith G. J. D.
Published: December 2017

Bartonella species are arthropod‐borne bacterial pathogens that infect numerous mammalian species. Small mammals play an important role as natural reservoirs of many Bartonella species, maintaining the greatest diversity of Bartonella described to date. Although Bartonella research has been conducted in Southeast Asia, no studies have been undertaken on small mammals in Singapore. Here, we report the detection and description of Bartonella in small mammals in Singapore during the period of November 2011 to May 2014. BartonellaDNA was detected in 20.8% (22/106) of small mammal spleens with a PCR amplifying the beta subunit of bacterial RNA polymerase (rpoB) gene. Commensal species Rattus norvegicus and Rattus tanezumi had the highest prevalence, 75% (3/4) and 34,5% (10/29), followed by Suncus murinus 30% (6/20), Tupaia glis 16,7% (1/6) and Mus castaneus 13.3% (2/15). Phylogenetic analysis of 18 rpoB gene sequences revealed five Bartonella genotypes circulating in the small mammals of Singapore. Bayesian tip‐significance testing demonstrated strong structuring in the geographical signal, indicating that distribution of Bartonella species is correlated to the distribution of their hosts. Major deforestation and fragmentation in Singapore favour synanthropic species that traverse habitats and increase the possibility of spillover to incidental hosts.
Pickup position and plucking point estimation on an electric guitar via autocorrelation
Authors: Mohamad Zulfadhli , Dixon Simon , Harte Christopher
Published: December 2017

This paper proposes a technique that estimates the locations along the string of the plucking event and the magnetic pickup of an electric guitar based on the autocorrelation of the spectral peaks. To improve accuracy, a method is introduced to flatten the spectrum before applying the autocorrelation function to the spectral peaks. The minimum mean squared error between the autocorrelation of the observed data and the electric guitar model is found in order to estimate the model parameters. The accuracy of the algorithm is tested on various plucking positions on all open strings for each pickup configuration. The accuracy of the proposed method for various plucking dynamics and fret positions is also evaluated. The method yields accurate results: the average absolute errors of the pickup position and plucking point estimates for single pickups are 3.53 and 5.11 mm, respectively, and for mixed pickups are 8.47 and 9.95 mm, respectively. The model can reliably distinguish which pickup configuration is selected using the pickup position estimates. Moreover, the method is robust to changes in plucking dynamics and fret positions.
Structure of the Paramyxovirus Parainfluenza Virus 5 Nucleoprotein in Complex with an Amino-Terminal Peptide of the Phosphoprotein
Authors: Aggarwal Megha , Leser George P. , Kors Christopher A. , Lamb Robert A.
Published: December 2017

Parainfluenza virus 5 (PIV5) belongs to the family
Paramyxoviridae
, which consists of enveloped viruses with a nonsegmented negative-strand RNA genome encapsidated by the nucleoprotein (N). Paramyxovirus replication is regulated by the phosphoprotein (P) through protein-protein interactions with N and the RNA polymerase (L). The chaperone activity of P is essential to maintain the unassembled RNA-free form of N in order to prevent nonspecific RNA binding and premature N oligomerization. Here, we determined the crystal structure of unassembled PIV5 N in complex with a P peptide (N
0
P) derived from the N terminus of P (P50) at 2.65 Å. The PIV5 N
0
P consists of two domains: an N-terminal domain (NTD) and a C-terminal domain (CTD) separated by a hinge region. The cleft at the hinge region of RNA-bound PIV5 N was previously shown to be an RNA binding site. The N
0
P structure shows that the P peptide binds to the CTD of N and extends toward the RNA binding site to inhibit N oligomerization and, hence, RNA binding. Binding of P peptide also keeps the PIV5 N in the open form. A molecular dynamics (MD) analysis of both the open and closed forms of N shows the flexibility of the CTD and the preference of the N protein to be in an open conformation. The gradual opening of the hinge region, to release the RNA, was also observed. Together, these results advance our knowledge of the conformational swapping of N required for the highly regulated paramyxovirus replication.

IMPORTANCE
Paramyxovirus replication is regulated by the interaction of P with N and L proteins. Here, we report the crystal structure of unassembled parainfluenza virus 5 (PIV5) N chaperoned with P peptide. Our results provide a detailed understanding of the binding of P to N. The conformational switching of N between closed and open forms during its initial interaction with P, as well as during RNA release, was analyzed. Our data also show the plasticity of the CTD and the importance of domain movement for conformational switching. The results improve our understanding of the mechanism of interchanging N conformations for RNA replication and release.
Prophages and Growth Dynamics Confound Experimental Results with Antibiotic-Tolerant Persister Cells
Authors: Harms Alexander , Fino Cinzia , Sørensen Michael A. , Semsey Szabolcs , Gerdes Kenn
Published: December 2017

Bacterial persisters are phenotypic variants that survive antibiotic treatment in a dormant state and can be formed by multiple pathways. We recently proposed that the second messenger (p)ppGpp drives
Escherichia coli
persister formation through protease Lon and activation of toxin-antitoxin (TA) modules. This model found considerable support among researchers studying persisters but also generated controversy as part of recent debates in the field. In this study, we therefore used our previous work as a model to critically examine common experimental procedures to understand and overcome the inconsistencies often observed between results of different laboratories. Our results show that seemingly simple antibiotic killing assays are very sensitive to variations in culture conditions and bacterial growth phase. Additionally, we found that some assay conditions cause the killing of antibiotic-tolerant persisters via induction of cryptic prophages. Similarly, the inadvertent infection of mutant strains with bacteriophage ϕ80, a notorious laboratory contaminant, apparently caused several of the phenotypes that we reported in our previous studies. We therefore reconstructed all infected mutants and probed the validity of our model of persister formation in a refined assay setup that uses robust culture conditions and unravels the dynamics of persister cells through all bacterial growth stages. Our results confirm the importance of (p)ppGpp and Lon but no longer support a role of TA modules in
E. coli
persister formation under unstressed conditions. We anticipate that the results and approaches reported in our study will lay the ground for future work in the field.

IMPORTANCE
The recalcitrance of antibiotic-tolerant persister cells is thought to cause relapsing infections and antibiotic treatment failure in various clinical setups. Previous studies identified multiple genetic pathways involved in persister formation but also revealed reproducibility problems that sparked controversies about adequate tools to study persister cells. In this study, we unraveled how typical antibiotic killing assays often fail to capture the biology of persisters and instead give widely differing results based on poorly controlled experimental parameters and artifacts caused by cryptic as well as contaminant prophages. We therefore established a new, robust assay that enabled us to follow the dynamics of persister cells through all growth stages of bacterial cultures without distortions by bacteriophages. This system also favored adequate comparisons of mutant strains with aberrant growth phenotypes. We anticipate that our results will contribute to a robust, common basis for future studies on the formation and eradication of antibiotic-tolerant persisters.
Probing split-ring resonator permeabilities with loop-gap resonators
Authors: Bobowski J.S.
Published: December 2017

A method is proposed to experimentally determine the effective complex permeability of split-ring resonator (SRR) arrays used in the design of metamaterials at microwave frequencies. We analyze the microwave response of a loop-gap resonator (LGR) whose bore has been partially loaded with one or more SRRs. Our analysis reveals that the resonance frequency, magnetic plasma frequency, and damping constant of the effective permeability of the SRR array can be extracted from fits to the reflection coefficient (S11) of an inductively coupled LGR. We propose LGR designs that would allow both a one-dimensional array of SRRs and small three-dimensional arrays of SRRs to be characterized. Finally, we demonstrate the method using a toroidal LGR loaded with a single extended SRR of length z.
Emergent universe model with dissipative effects
Authors: Debnath P. S. , Paul B. C.
Published: December 2017

Emergent universe model is presented in general theory of relativity with isotropic fluid in addition to viscosity. We obtain cosmological solutions that permit emergent universe scenario in the presence of bulk viscosity that are described by either Eckart theory or Truncated Israel Stewart (TIS) theory. The stability of the solutions are also studied. In this case, the emergent universe (EU) model is analyzed with observational data. In the presence of viscosity, one obtains emergent universe scenario, which however is not permitted in the absence of viscosity. The EU model is compatible with cosmological observations.
Generating Fine-Grain Multithreaded Applications Using a Multigrain Approach
Authors: Arteaga Jaime , Zuckerman Stéphane , Gao Guang R.
Published: December 2017

The recent evolution in hardware landscape, aimed at producing high-performance computing systems capable of reaching extreme-scale performance, has reignited the interest in fine-grain multithreading, particularly at the intranode level. Indeed, popular parallel programming environments, such as OpenMP, which features a simple interface for the parallelization of programs, are now incorporating fine-grain constructs. However, since coarse-grain directives are still heavily used, the OpenMP runtime is forced to support both coarse- and fine-grain models of execution, potentially reducing the advantages obtained when executing an application in a fully fine-grain environment. To evaluate the type of applications that benefit from executing in a unified fine-grain program execution model, this article presents a
multigrain parallel programming environment
for the generation of fine-grain multithreaded applications from programs featuring OpenMP’s API, allowing OpenMP programs to be run on top of a fine-grain event-driven program execution model. Experimental results with five scientific benchmarks show that fine-grain applications, generated by and run on our environment with two runtimes implementing a fine-grain event-driven program execution model, are competitive and can outperform their OpenMP counterparts, especially for data-intensive workloads with irregular and dynamic parallelism, reaching speedups as high as 2.6× for Graph500 and 51× for NAS Data Cube.
Practical Solution for Effective Whole-Body Magnetic Fluid Hyperthermia Treatment
Authors: Mamiya Hiroaki , Takeda Yoshihiko , Naka Takashi , Kawazoe Naoki , Chen Guoping , Jeyadevan Balachandran
Published: December 2017

Magnetic fluid hyperthermia therapy is considered as a promising treatment for cancers including unidentifiable metastatic cancers that are scattered across the whole body. However, a recent study on heat transfer simulated on a human body model showed a serious side effect: occurrences of hot spots in normal tissues due to eddy current loss induced by variation in the irradiated magnetic field. The indicated allowable upper limit of field amplitude Hac for constant irradiation over the entire human body corresponded to approximately 100 Oe at a frequency f of 25 kHz. The limit corresponds to the value Hacf of 2.5 × 106 Oe·s−1 and is significantly lower than the conventionally accepted criteria of 6 × 107 Oe·s−1. The present study involved evaluating maximum performance of conventional magnetic fluid hyperthermia cancer therapy below the afore-mentioned limit, and this was followed by discussing alternative methods not bound by standard frameworks by considering steady heat flow from equilibrium responses of stable nanoparticles. Consequently, the clarified potentials of quasi-stable core-shell nanoparticles, dynamic alignment of easy axes, and short pulse irradiation indicate that the whole-body magnetic fluid hyperthermia treatment is still a possible candidate for future cancer therapy.
Impact of Petrophysical Properties on Hydraulic Fracturing and Development in Tight Volcanic Gas Reservoirs
Authors: Shen Yinghao , Meng Mianmo , Liu Tao , Ge Hongkui , Zhang Yuelei
Published: December 2017

The volcanic reservoir is an important kind of unconventional reservoir. The aqueous phase trapping (APT) appears because of fracturing fluids filtration. However, APT can be autoremoved for some wells after certain shut-in time. But there is significant distinction for different reservoirs. Experiments were performed to study the petrophysical properties of a volcanic reservoir and the spontaneous imbibition is monitored by nuclear magnetic resonance (NMR) and pulse-decay permeability. Results showed that natural cracks appear in the samples as well as high irreducible water saturation. There is a quick decrease of rock permeability once the rock contacts water. The pores filled during spontaneous imbibition are mainly the nanopores from NMR spectra. Full understanding of the mineralogical effect and sample heterogeneity benefits the selection of segments to fracturing. The fast flow-back scheme is applicable in this reservoir to minimize the damage. Because lots of water imbibed into the nanopores, the main flow channels become larger, which are beneficial to the permeability recovery after flow-back of hydraulic fracturing. This is helpful in understanding the APT autoremoval after certain shut-in time. Also, Keeping the appropriate production differential pressure is very important in achieving the long term efficient development of volcanic gas reservoirs.
Distributed Image Compression Architecture over Wireless Multimedia Sensor Networks
Authors: Heng Sovannarith , So-In Chakchai , Nguyen Tri Gia
Published: December 2017

In a wireless multimedia sensor network (WMSN), the minimization of network energy consumption is a crucial task not just for scalar data but also for multimedia. In this network, a camera node (CN) captures images and transmits them to a base station (BS). Several sensor nodes (SNs) are also placed throughout the network to facilitate the proper functioning of the network. Transmitting an image requires a large amount of energy due to the image size and distance; however, SNs are resource constrained. Image compression is used to scale down image size; however, it is accompanied by a computational complexity trade-off. Moreover, direct image transmission to a BS requires more energy. Thus, in this paper, we present a distributed image compression architecture over WMSN for prolonging the overall network lifetime (at high throughput). Our scheme consists of three subtasks: determining the optimal camera radius for prolonging the CN lifetime, distributing image compression tasks among the potential SNs to balance the energy, and, finally, adopting a multihop hierarchical routing scheme to reduce the long-distance transmission energy. Simulation results show that our scheme can prolong the overall network lifetime and achieve high throughput, in comparison with a traditional routing scheme and its state-of-the-art variants.
Different Dietary Proportions of Fish Oil Regulate Inflammatory Factors but Do Not Change Intestinal Tight Junction ZO-1 Expression in Ethanol-Fed Rats
Authors: Chien Yi-Wen , Peng Hsiang-Chi , Chen Ya-Ling , Pai Man-Hui , Wang Hsiao-Yun , Chuang Hsiao-Li , Yang Suh-Ching
Published: December 2017

Sixty male Wistar rats were fed a control or an ethanol-containing diet in groups C or E. The fat compositions were adjusted with 25% or 57% fish oil substituted for olive oil in groups CF25, CF57, EF25, and EF57. Hepatic thiobarbituric acid-reactive substance (TBARS) levels, cytochrome P450 2E1 protein expression, and tumor necrosis factor- (TNF-)α, interleukin- (IL-) 1β, IL-6, and IL-10 levels, as well as intracellular adhesion molecule (ICAM)-1 levels were significantly elevated, whereas plasma adiponectin level was significantly reduced in group E (p<0.05). Hepatic histopathological scores of fatty change and inflammation, in group E were significantly higher than those of group C (p<0.05). Hepatic TBARS, plasma ICAM-1, and hepatic TNF-α, IL-1β, and IL-10 levels were significantly lower, and plasma adiponectin levels were significantly higher in groups EF25 and EF57 than those in group E (p<0.05). The immunoreactive area of the intestinal tight junction protein, ZO-1, showed no change between groups C and E. Only group CF57 displayed a significantly higher ZO-1 immunoreactive area compared to group C (p=0.0415). 25% or 57% fish oil substituted for dietary olive oil could prevent ethanol-induced liver damage in rats, but the mechanism might not be related to intestinal tight junction ZO-1 expression.
Therapeutic Potential of Novel Twin Compounds Containing Tetramethylpyrazine and Carnitine Substructures in Experimental Ischemic Stroke
Authors: Wang Ziying , Zhou Zhuanli , Wei Xinbing , Wang Mingwei , Wang Bi-Ou , Zhang Yanan , He Xiaoting , Sun Yu , Wang Xiaojie , Sun Mingcheng , Zhang Yan , Gong Xiaowei , Yi Fan
Published: December 2017

Although studies have seen dramatic advances in the understanding of the pathogenesis of stroke such as oxidative stress, inflammation, excitotoxicity, calcium overload and apoptosis, the delivery of stroke therapies is still a great challenge. In this study, we designed and synthesized a series of novel twin compounds containing tetramethylpyrazine and carnitine substructures and explored their therapeutic potential and mechanism in stroke‐related neuronal injury. We first screened the neuroprotective effects of candidate compounds and found that among the tested compounds, LR134 and LR143 exhibited significant neuroprotection as evidenced by reducing cerebral infarct and edema, improving neurological function as well as blood‐brain barrier integrity in rats after cerebral ischemia/reperfusion injury. We further demonstrated that the neuroprotective effects of compounds LR134 and LR143 were associated with the reduced inflammatory responses and NADPH oxidase‐ (NOX2‐) mediated oxidative stress and the protection of mitochondria accompanied by the improvement of energy supply. In summary, this study provides direct evidence showing that the novel twin compounds containing tetramethylpyrazine and carnitine substructures have neuroprotective effects with multiple therapeutic targets, suggesting that modulation of these chemical structures may be an innovative therapeutic strategy for treating patients with stroke.
Statistical Antenna Proximity Effect Modeling with Uncertainty Impedance Ellipses
Authors: Carro Pedro Luis , de Mingo Jesús , García-Dúcar Paloma , Valdovinos Antonio
Published: December 2017

User effects on portable antennas can decrease the global terminal performance, such as reducing the battery life or the wireless coverage. People presence will modify the input impedance, the far field radiation pattern, the radiation efficiency, and the near field. In this paper, we investigate the influence of the user on the input impedance by means of a new statistical approach which relies on uncertainty, where a handheld antenna works in two modes (data and talk) while people couple to the antenna. Studying some reflection coefficient measurements performed with a vector network analyzer (VNA), a standard framework based on uncertainty ellipses is developed. Finally, the method is applied to some antenna prototypes, showing its advantages and reliability to quantify and compare proximity effects.
Analysis of a Generalized Lorenz–Stenflo Equation
Authors: Zhang Fuchen , Chen Rui , Chen Xiusu
Published: December 2017

Although the globally attractive sets of a hyperchaotic system have important applications in the fields of engineering, science, and technology, it is often a difficult task for the researchers to obtain the globally attractive set of the hyperchaotic systems due to the complexity of the hyperchaotic systems. Therefore, we will study the globally attractive set of a generalized hyperchaotic Lorenz–Stenflo system describing the evolution of finite amplitude acoustic gravity waves in a rotating atmosphere in this paper. Based on Lyapunov-like functional approach combining some simple inequalities, we derive the globally attractive set of this system with its parameters. The effectiveness of the proposed methods is illustrated via numerical examples.
A Novel Surrogate Safety Indicator Based on Constant Initial Acceleration and Reaction Time Assumption
Authors: Fazekas Adrian , Hennecke Friederike , Kalló Eszter , Oeser Markus
Published: December 2017

The development of surrogate safety measures has drawn significant research interest in the field of traffic safety analysis. Innovative data sources such as video-based traffic surveillance systems have made it possible to collect large amounts of microscopic traffic data. By deriving traffic safety indicators such as the Deceleration Rate to Avoid a Crash (DRAC) statements concerning traffic safety over a determined road section can be made. This work presents the derivation of a novel surrogate safety indicator based on a Constant Initial Acceleration and reaction time assumption which considers the interaction between vehicles and describes the traffic safety of a road section. The evaluation is based on a video-based microscopic traffic data collection. To examine the efficiency, the new developed indicator is compared to the original Deceleration Rate to Avoid a Crash (DRAC) and the modified indicator (MDRAC) which includes the reaction time. The results showed that the new indicator is more sensitive in detecting critical situations than the other indicators and in addition describes the conflict situations more realistically.
The Effect of a Short‐Term Exposure to Lead on the Levels of Essential Metal Ions, Selected Proteins Related to Them, and Oxidative Stress Parameters in Humans
Authors: Dobrakowski Michał , Boroń Marta , Birkner Ewa , Kasperczyk Aleksandra , Chwalińska Ewa , Lisowska Grażyna , Kasperczyk Sławomir
Published: December 2017

The present study was designed to explore the possible influence of subacute exposure to lead on the levels of selected essential metals, selected proteins related to them, and oxidative stress parameters in occupationally exposed workers. The study population included 36 males occupationally exposed to lead for 36 to 44 days. Their blood lead level at the beginning of the study was 10.7 ± 7.67 μg/dl and increased to the level of 49.1 ± 14.1 μg/dl at the end of the study. The levels of calcium, magnesium, and zinc increased significantly after lead exposure compared to baseline by 3%, 3%, and 8%, respectively, while the level of copper decreased significantly by 7%. The malondialdehyde (MDA) level and the activities of catalase (CAT) and superoxide dismutase (SOD) did not change due to lead exposure. However, the level of lipid hydroperoxides (LPH) in serum increased significantly by 46%, while the level of erythrocyte lipofuscin (LPS) decreased by 13%. The serum levels of essential metals are modified by a short‐term exposure to lead in occupationally exposed workers. A short‐term exposure to lead induces oxidative stress associated with elevated levels of LPH but not MDA.
HIF1α-Induced Glycolysis Metabolism Is Essential to the Activation of Inflammatory Macrophages
Authors: Wang Ting , Liu Huiying , Lian Guan , Zhang Song-Yang , Wang Xian , Jiang Changtao
Published: December 2017

Hypoxia-inducible factor (HIF) 1αis a metabolic regulator that plays an important role in immunologic responses. Previous studies have demonstrated that HIF1αparticipates in the M1 polarization of macrophages. To clarify the mechanism of HIF1α-induced polarization of M1 macrophage, myeloid-specific HIF1αoverexpression (Lysm HIF1αlsl) mice were employed and the bone marrow-derived and peritoneal macrophages were isolated. RT-PCR results revealed that HIF1αoverexpression macrophage had a hyperinflammatory state characterized by the upregulation of M1 markers. Cellular bioenergetics analysis showed lower cellular oxygen consumption rates in the Lysm HIF1αlsl mice. Metabolomics studies showed that HIF1αoverexpression led to increased glycolysis and pentose phosphate pathway intermediates. Further results revealed that macrophage M1 polarization, induced by HIF1αoverexpression, was via upregulating the mRNA expression of the genes related to the glycolysis metabolism. Our results indicate that HIF1αpromoted macrophage glycolysis metabolism, which induced M1 polarization in mice.
Hypoxia Accelerates Aggressiveness of Hepatocellular Carcinoma Cells Involving Oxidative Stress, Epithelial-Mesenchymal Transition and Non-Canonical Hedgehog Signaling
Authors: Liu Zhikui , Tu Kangsheng , Wang Yufeng , Yao Bowen , Li Qing , Wang Liang , Dou Changwei , Liu Qingguang , Zheng Xin
Published: December 2017

Background/Aims: Hypoxic microenvironment, a common feature of hepatocellular carcinoma (HCC), can induce HIF-1α expression and promote the epithelial-mesenchymal transition (EMT) and invasion of cancer cells. However, the underlying molecular mechanisms have not fully elucidated. Methods: HCC cells were cultured under controlled hypoxia conditions or normoxic conditions. Transwell assays were used to examine the migration and invasion capacity. HIF-1α siRNA, cyclopamine (a SMO antagonist) and GLI1 siRNA were used to inhibit HIF-1α transcription or Hh signaling activation. Results: In present study, we first observed a strongly positive correlation between HIF-1α and GLI1 expression in HCC tissues. Then, we showed that hypoxia significantly promoted EMT process and invasion of HCC cells, associated with activating the non-canonical Hh pathway without affecting SHH and PTCH1 expression. HIF-1α knockdown mitigated hypoxia-induced SMO and GLI1 expression, EMT invasion of HCC cells. Moreover, the SMO inhibitor or GLI1 siRNA also reversed the hypoxia-driven EMT and invasion of HCC cells under hypoxia condition. Here, we show that non-canonical Hh signaling is required as an important role to switch on hypoxia-induced EMT and invasion in HCC cells. In addition, we found that hypoxia increased ROS production and that ROS inhibitors (NAC) blocked GLI1-dependent EMT process and invasion under hypoxic conditions. To determine a major route of ROS production, we tested whether nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 4 (NOX4) is involved in hypoxia-induced ROS production. NOX4 expression was found to be increased at both mRNA and protein levels in hypoxic HCC cells. Furthermore, siRNA-mediated knockdown of NOX4 expression abolished hypoxia induced ROS generation and GLI1-dependent activation and invasion of HCC cells. Conclusion: Our findings indicate that hypoxia triggers ROS-mediated GLI1-dependent EMT progress and invasion of HCC cells through induction of NOX4 expression. Thus, hypoxia-driven ROS mediated non-canonical Hh signaling may play an important role in the initiation of EMT and provides a potential marker for cancer prevention and treatment.
O lugar da América Latina nas relações sul-sul: o papel da Comunidade de Estados Latino-Americanos e Caribenhos (CELAC) na integração latino-americana
Authors: Pereira Francisco Denes
Published: December 2017

A integração latino-americana e caribenha ganhou uma nova organização com a criação da Comunidade de Estados Latino-Americanos e Caribenhos (CELAC). O objetivo principal do desse artigo é analisar a criação da CELAC e seu papel no processo de integração latino-americano atual. Atenta-se a compreender a construção do diálogo e da concertação política entre os países latino-americanos e qual o balanço dos resultados dessas iniciativas. Aprofunda-se o estudo sobre a criação da CELAC, sua conformação institucional, assim como seus principais desafios frente à existência da Organização dos Estados Americanos (OEA) e sua efetividade.
Corruption, Crime Victimization, and Community Participation in Latin America
Authors: Armesto Alejandra
Published: December 2017

Estudos sobre a relação entre a vitimização e capital social sustentam hipóteses contraditórias:a vitimização criminal leva ao isolamento social e maior participação. Sob que condições a vitimização pelo crime induz a participação em associações comunitárias? Este artigo argumenta que essa relação é condicionada pela corrupção do governo. Esta hipótese é testada com dados coletados em 2012 em 18 países da América Latina pelo Barômetro das Américas. Usando regressão linear hierárquica, o estudo mostra que as vítimas de crimes participaram em organizações comunitárias em uma taxa maior do que as não-vítimas, e que essa participação é ainda maior em países com altos níveis de corrupção no governo.
Capitalismo extrativista na América Latina e as contradições da mineração em grande escala no Brasil
Authors: Gonçalves Ricardo Junior de Assis Fernandes
Published: December 2017

Na primeira década do século XXI, o aumento do preço de commodities minerais como minério de ferro, cobre, ouro e alumínio, fortaleceu a expansão de novas fronteiras do extrativismo mineral na América Latina. Desse modo, o objetivo desta pesquisa é compreender os efeitos da mineração na economia e em territórios impactados por mega empreendimentos em países latino-americanos. Para isso, num segundo momento a centralidade da investigação priorizou a realidade brasileira. O modelo de extrativismo mineral exportador baseado nos grandes projetos fortalece estratégias de controle dos territórios e acumulação por espoliação. A escala de produção e consumo, os métodos e ritmos extrativos, assim como o uso e desperdício dos próprios minérios, água e energia ilustram a insustentabilidade e as contradições da mineração no Brasil e na América Latina.
Genome-Wide Association Study Implicates Atrial Natriuretic Peptide Rather Than B-Type Natriuretic Peptide in the Regulation of Blood Pressure in the General Population
Authors: Salo Perttu P. , Havulinna Aki S. , Tukiainen Taru , Raitakari Olli , Lehtimäki Terho , Kähönen Mika , Kettunen Johannes , Männikkö Minna , Eriksson Johan G. , Jula Antti , Blankenberg Stefan , Zeller Tanja , Salomaa Veikko , Kristiansson Kati , Perola Markus
Published: December 2017

Background—

Cardiomyocytes secrete atrial natriuretic peptide (ANP) and B-type natriuretic peptide (BNP) in response to mechanical stretching, making them useful clinical biomarkers of cardiac stress. Both human and animal studies indicate a role for ANP as a regulator of blood pressure with conflicting results for BNP.

Methods and Results—

We used genome-wide association analysis (n=6296) to study the effects of genetic variants on circulating natriuretic peptide concentrations and compared the impact of natriuretic peptide–associated genetic variants on blood pressure (n=27 059). Eight independent genetic variants in 2 known (
NPPA-NPPB
and
POC1B-GALNT4
) and 1 novel locus (
PPP3CC
) associated with midregional proANP (MR-proANP), BNP, aminoterminal proBNP (NT-proBNP), or BNP:NT-proBNP ratio. The
NPPA-NPPB
locus containing the adjacent genes encoding ANP and BNP harbored 4 independent
cis
variants with effects specific to either midregional proANP or BNP and a rare missense single nucleotide polymorphism in NT-proBNP seriously altering its measurement. Variants near the calcineurin catalytic subunit gamma gene
PPP3CC
and the polypeptide N-acetylgalactosaminyltransferase 4 gene
GALNT4
associated with BNP:NT-proBNP ratio but not with BNP or midregional proANP, suggesting effects on the post-translational regulation of proBNP. Out of the 8 individual variants, only those correlated with midregional proANP had a statistically significant albeit weak impact on blood pressure. The combined effect of these 3 single nucleotide polymorphisms also associated with hypertension risk (
P
=8.2×10
−
4
).

Conclusions—

Common genetic differences affecting the circulating concentration of ANP associated with blood pressure, whereas those affecting BNP did not, highlighting the blood pressure–lowering effect of ANP in the general population.