bluuebunny/crossref_metadata_2025 huggingface dataset:
Umbilical cord-derived mesenchymal stem cell extracts reduce colitis in mice by re-polarizing intestinal macrophages
Authors: Song Ji-young , Kang Hyo Jeong , Hong Joon Seok , Kim Chong Jai , Shim Jae-Yoon , Lee Christopher W. , Choi Jene
Published: August 2017

Human umbilical cord mesenchymal stem cells (hUC-MSCs), originating in Wharton’s jelly, are multipotent stem cells that home to damaged tissues and can modulate the immune system. We examined whether administering extracts of MSCs (MSC-Ex) instead of MSCs could augment the beneficial effects of MSC therapy by overcoming the low homing efficiency of MSCs systemically administered in inflammatory bowel diseases (IBD). Dextran sodium sulfate-induced colitis model was established in C57BL/6 mice, and MSC-Ex was administered intraperitoneally. MSC-Ex reduced colitis, disease activity index (DAI), and histological colitis scores, and increased the body weight. Treatment with MSC-Ex completely blocked the induction of inflammatory cytokines, which were strongly detected in mice with colitis. MSC-Ex shifted the macrophage functional phenotype from M1 to M2 by decreasing the levels of MCP1, CXCL9, and iNOS, but increasing the levels of IL-10, LIGHT, CCL1, and Arg-1. MSC-Ex recovered the destruction of the epithelial barrier in the differentiated Caco-2 cells in vitro. Treatment with MSC-Ex was more potent than that with MSC in reducing DAI, the histological score, and nitrite levels. These data strongly support that MSC-Ex treatment can be a potent approach to overcome severe refractory IBD.
Fluorescent organic single crystals with elastic bending flexibility: 1,4-bis(thien-2-yl)-2,3,5,6-tetrafluorobenzene derivatives
Authors: Hayashi Shotaro , Asano Atsushi , Kamiya Natsumi , Yokomori Yoshinobu , Maeda Takuto , Koizumi Toshio
Published: August 2017

Organic single crystals with elastic bending flexibility are rare because they are generally brittle. We report here fluorescent organic single crystals based on thiophene-tetrafluorobenzene-thiophene derivatives, mainly 1,4-bis(thien-2-yl)-2,3,5,6-tetrafluorobenzene. Three derivatives were synthesized by Pd-catalyzed cross-coupling reactions (Stille or direct arylation pathways). The crystallization of the derivatives gave large (mm- or cm-scale) crystals. Two crystals of 1,4-bis(thien-2-yl)-2,3,5,6-tetrafluorobenzene, 1, and 1,4-bis(4-methylthien-2-yl)-2,3,5,6-tetrafluorobenzene, 3, bent under applied stress and quickly recovered its original shape upon relaxation. The other crystal of 1,4-bis(5-methylthien-2-yl)-2,3,5,6-tetrafluorobenzene, 2, showed brittle breakage under applied stress (normal behavior). Fibril lamella crystal structure based on criss-cross packed slip-stacked molecular wires and its structural integrity are important factors for the design and production of next generation crystal materials with elastic bending flexibility. Furthermore, mechanical bending–relaxation resulted in reversible change of the morphology and fluorescence (mechanofluorochromism). Such bendable crystals would lead to the next generation solid-state fluorescent and/or semiconducting materials.
Simultaneous Gene Delivery and Tracking through Preparation of Photo-Luminescent Nanoparticles Based on Graphene Quantum Dots and Chimeric Peptides
Authors: Ghafary Soroush Moasses , Nikkhah Maryam , Hatamie Shadie , Hosseinkhani Saman
Published: August 2017

Designing suitable nano-carriers for simultaneous gene delivery and tracking is in the research priorities of the molecular medicine. Non-toxic graphene quantum dots (GQDs) with two different (green and red) emission colors are synthesized by Hummer’s method and characterized by UV-Vis, Photoluminescence (PL), Fourier Transform Infrared (FTIR) and Raman spectroscopies, Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). The GQDs are conjugated with MPG-2H1 chimeric peptide and plasmid DNA (pDNA) by non-covalent interactions. Following conjugation, the average diameter of the prepared GQDs increased from 80 nm to 280 nm in complex structure, and the ζ-potential of the complex increased (from −36.87 to −2.56 mV). High transfection efficiency of the nano-carrier and results of confocal microscopy demonstrated that our construct can be considered as a nontoxic carrier with dual functions for gene delivery and nuclear targeting.
Strong electric wave response derived from the hybrid of lotus roots-like composites with tunable permittivity
Authors: Liang Xiaohui , Quan Bin , Chen Jiabin , Tang Dongming , Zhang Baoshan , Ji Guangbin
Published: August 2017

Lotus roots-like NiO/NiCo2O4 hybrids derived from Metal-organic frameworks (MOFs) are fabricated for the first time by using flake NiCo-MOF precursors as reactant templates. It was found that a thin sample consisting of 60 wt % NiO/NiCo2O4 hybrids in the wax matrix exhibited an effective microwave absorption bandwidth of 4.2 GHz at the thickness of 1.6 mm. The highest reflection loss of −47 dB was observed at 13.4 GHz for a sample with a thickness of 1.7 mm. Results obtained in this study indicate that hybrids of NiO and NiCo2O4 are promising microwave absorbing materials with adjustable permittivity, which can exhibit broad effective absorption bandwidth at low filler loading and thin thickness.
In situ repair of bone and cartilage defects using 3D scanning and 3D printing
Authors: Li Lan , Yu Fei , Shi Jianping , Shen Sheng , Teng Huajian , Yang Jiquan , Wang Xingsong , Jiang Qing
Published: August 2017

Three-dimensional (3D) printing is a rapidly emerging technology that promises to transform tissue engineering into a commercially successful biomedical industry. However, the use of robotic bioprinters alone is not sufficient for disease treatment. This study aimed to report the combined application of 3D scanning and 3D printing for treating bone and cartilage defects. Three different kinds of defect models were created to mimic three orthopedic diseases: large segmental defects of long bones, free-form fracture of femoral condyle, and International Cartilage Repair Society grade IV chondral lesion. Feasibility of in situ 3D bioprinting for these diseases was explored. The 3D digital models of samples with defects and corresponding healthy parts were obtained using high-resolution 3D scanning. The Boolean operation was used to achieve the shape of the defects, and then the target geometries were imported in a 3D bioprinter. Two kinds of photopolymerized hydrogels were synthesized as bioinks. Finally, the defects of bone and cartilage were restored perfectly in situ using 3D bioprinting. The results of this study suggested that 3D scanning and 3D bioprinting could provide another strategy for tissue engineering and regenerative medicine.
Superior Electronic Structure in Two-Dimensional MnPSe
3

/MoS2 van der Waals Heterostructures
Authors: Pei Qi , Song Yan , Wang Xiaocha , Zou Jijun , Mi Wenbo
Published: August 2017

We explore the electronic structure of two-dimensional (2D) MnPSe3/MoS2 van der Waals (vdW) heterostructures based on density functional theory. A novel spin splitting at the valance band maximum of MnPSe3 appears in some specific stacking models due to Mn d orbital hybridization. The simultaneous spin and valley splitting can be achieved by interfacial coupling, which is attractive for manipulation of the valley and spin degrees of freedom. More importantly, due to the antiferromagnetic ordering of manganese, the opposite spin moments at K and K′ valleys can be observed by transforming configurations, which realizes the tunable spin splitting states. Our theoretical work opens up the opportunities of valley and spin related applications of MnPSe3/MoS2 vdW heterostructures and offers a practical avenue for exploring novel devices based on the spin and valley degrees of freedom.
The Parkinson’s disease-associated GPR37 receptor interacts with striatal adenosine A2A receptor controlling its cell surface expression and function in vivo
Authors: Morató Xavier , Luján Rafael , López-Cano Marc , Gandía Jorge , Stagljar Igor , Watanabe Masahiko , Cunha Rodrigo A. , Fernández-Dueñas Víctor , Ciruela Francisco
Published: August 2017

G protein-coupled receptor 37 (GPR37) is an orphan receptor associated to Parkinson’s disease (PD) neuropathology. Here, we identified GPR37 as an inhibitor of adenosine A2Areceptor (A2AR) cell surface expression and functionin vivo. In addition, we showed that GPR37 and A2AR do oligomerize in the striatum. Thus, a close proximity of GPR37 and A2AR at the postsynaptic level of striatal synapses was observed by double-labelling post-embedding immunogold detection. Indeed, the direct receptor-receptor interaction was further substantiated by proximity ligationin situassay. Interestingly, GPR37 deletion promoted striatal A2AR cell surface expression that correlated well with an increased A2AR agonist-mediated cAMP accumulation, both in primary striatal neurons and nerve terminals. Furthermore, GPR37−/− mice showed enhanced A2AR agonist-induced catalepsy and an increased response to A2AR antagonist-mediated locomotor activity. Overall, these results revealed a key role for GPR37 controlling A2AR biology in the striatum, which may be relevant for PD management.
Structure and magnetic properties of icosahedral PdxAg13−x (x = 0–13) clusters
Authors: Fan Bai , Ge Gui-Xian , Jiang Cheng-Huan , Wang Guang-Hou , Wan Jian-guo
Published: August 2017

In this article, we present a modified Velocity-Verlet algorithm that makes cluster system converge rapidly and accurately. By combining it with molecular dynamics simulations, we develop an effective global sampling method for extracting isomers of bimetallic clusters. Using this method, we obtain the isomers of icosahedral PdxAg13−x (x = 0–13). Additionally, using the first-principle spin-polarized density functional theory approach, we find that each isomer still retains its icosahedral structure because of strong s-d orbital hybridization, and the cluster is more stable when a Pd atom is at the center of the cluster. With increasing x value, the magnetic moment decreases linearly from 5.0 μB at x = 0, until reaching zero at x = 5, and then increases linearly up to 8.0 μB at x = 13. By calculating the atom-projected density of states (PDOS), we reveal that the magnetic moment of PdxAg13−x mainly originates from s electrons of Ag when 0 ≤ x < 5, and d electrons of Pd when 5 < x ≤ 13. The PDOS results also show that the PdxAg13−x tends to transform from a semiconductor state to semi-metallic state when x gradually increases from 0 to 13.
Poly-Methyl Methacrylate/Polyvinyl Alcohol Copolymer Agents Applied on Diabetic Wound Dressing
Authors: Hsieh Hsiao-Ting , Chang Hung-Ming , Lin Wei-Jhih , Hsu Yao-Tsung , Mai Fu-Der
Published: August 2017

Due to the difficulty of healing chronic wound, in the process of changing dressing, secondary damage on the tissue caused by adhesion should be prevented. In this study, the new dressing of particle hydrogels synthesized with poly-methyl methacrylate and poly-vinyl alcohol precursors were proposed. In addition, cell safety tests, animal’s allergic stimulation, and animal’s wound healing experiments were conducted for particle hydrogels. On one hand, in L929 cell experiment, the results of particle hydrogels extract 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide tests and lactate dehydrogenase test trial show that there are no safety concerns over particle hydrogels. On the other hand, New Zealand white rabbits were chosen for skin sensitization tests in animal trials, which show the consistent results. At last, wound healing tests used diabetes induction with 10-week-old rats and three-month-old Landrace pigs, with the tissue histology. In short, through this experiment, it is found that in the early phase of the diabetic rats and pigs’ wound healing, using particle hydrogels can enhance collagen formation, and achieve the goal of faster wound healing.
Relationship between initiation time of adjuvant chemotherapy and survival in ovarian cancer patients: a dose-response meta-analysis of cohort studies
Authors: Liu Yi , Zhang Tiening , Wu Qijun , Jiao Yisheng , Gong Tingting , Ma Xiaoxin , Li Da
Published: August 2017

Although several studies have previously investigated the association between the initiation time of adjuvant chemotherapy and survival in ovarian cancer, inconsistencies remain about the issue. We searched PubMed and Web of Science through the May 24, 2017 to identify cohort studies that investigated the aforementioned topic. Fourteen studies with 59,569 ovarian cancer patients were included in this meta-analysis. We conducted meta-analyses comparing the longest and shortest initiation time of adjuvant chemotherapy and dose-response analyses to estimate summary hazards ratios (HRs) and 95% confidence intervals (CIs). A random-effects model was used to estimate HRs with 95% CIs. When comparing the longest with the shortest category of initiation time of adjuvant chemotherapy, the summary HR was 1.18 (95% CI: 1.06–1.32; I2 = 17.6; n = 7) for overall survival. Additionally, significant dose-response association for overall survival was observed for each week delay (HR = 1.04; 95% CI: 1.00–1.09; I2 = 9.05; n = 5). Notably, these findings were robust in prospective designed cohort studies as well as studies with advanced stage (FIGO III-IV) patients. No evidence of publication bias was observed. In conclusion, prolonged initiation time of adjuvant chemotherapy is associated with a decreased overall survival rate of ovarian cancer, especially in patients with advanced stage ovarian cancer.
Sonic Hedgehog mimetic prevents leukocyte infiltration into the CNS during acute HIV infection
Authors: Singh Vir B. , Singh Meera V. , Piekna-Przybylska Dorota , Gorantla Santhi , Poluektova Larisa Y. , Maggirwar Sanjay B.
Published: August 2017

Infiltration of infected leukocytes culminates in establishment of a brain niche for Human Immunodeficiency Virus (HIV) during acute phase of infection, initiating an ongoing cascade of persistent viral replication and inflammation, that causes irreversible neuronal injury and HIV associated neurocognitive disease (HAND). In this study, humanized mice were treated with Smoothened Agonist (SAG), a Sonic Hedgehog (Shh) mimetic in order to fortify blood brain barrier (BBB) and dampen leukocyte extravasation into CNS during AHI. Results indicate that SAG treatment reduced viral burden in the CNS immediately after HIV transmission, but also conferred extended neuroprotection via increased BBB integrity (elevated levels of tight-junction protein, Claudin 5, and reduced S100B levels in periphery). These mice also showed healthier neurons with thick, uniform dendrites and reduced numbers of activated astrocytes. Additional in vitro experiments suggested SAG treatment was not associated with the establishment or reversal of latency in the target cells. Altogether, these findings validate neuroprotective role of Shh signaling and highlight the therapeutic potential of Shh mimetics against CNS complications associated with HIV infection. Further our results strongly demonstrate that pharmacological interventions to reduce leukocyte mobilization during early HIV infection, can provide prolonged neuroprotection, which might significantly delay the onset of HAND.
Marked seasonality and high spatial variation in estuarine ciliates are driven by exchanges between the ‘abundant’ and ‘intermediate’ biospheres
Authors: Sun Ping , Huang Liying , Xu Dapeng , Huang Bangqin , Chen Nengwang , Warren Alan
Published: August 2017

We examined the spatial and temporal variability of ciliate community in a subtropical estuary by rRNA and rDNA-based high throughput sequencing of 97 samples collected along the entire salinity gradient at two-month intervals in 2014. Community divided statistically into three groups: freshwater (salinity < 0.5‰), oligohaline and mesohaline (0.5‰ < salinity < 18‰), and polyhaline and euhaline (18‰ < salinity < 40‰). Across all three groups, salinity explained most of the community variability. Within each group, seasonal shifts in community formed cool (spring and winter) and warm (summer and autumn) subgroups, indicating that spatial variability overrode seasonal changes in determining community composition. Cool and warm groups showed opposite associations with temperature and prey proxies, suggesting distinct seasonal niche separation. The community reassembly of cool and warm groups was essentially due to transitions between intermediate (with relative abundance of 0.01–1%) and abundant (with relative abundance > 1%) OTUs. Further analyses demonstrated that the intermediate group not only encompassed comparable OTU richness to that of the total community and maintained high metabolic activity but also had the highest proportion in transition, either to abundance or rarity, thus offering a first view on how it varies across space and time and revealing the essential role it played in maintaining stability and functionality within the community.
Adhesion to stromal cells mediates imatinib resistance in chronic myeloid leukemia through ERK and BMP signaling pathways
Authors: Kumar Atul , Bhattacharyya Jina , Jaganathan Bithiah Grace
Published: August 2017

Chronic myeloid leukemia (CML) is characterized by abnormal proliferation of myeloid cells which when untreated leads to bone marrow failure. Imatinib mesylate (IM) is the first line of therapy for treatment of CML and results in remission in most cases. However, a significant percentage of patients develop chemoresistance to IM, which might be due to the presence of chemoresistant cells in the bone marrow. In the current study, we explored the role of cell-cell interaction of CML cells with the bone marrow stromal cells in the development of chemoresistance in CML. We found that the stromal cells offered long-term chemoprotection to the CML cells from the apoptotic effect of IM. These stroma interacting CML cells were maintained in a non-proliferative stage and had increased ERK1/2 and SMAD1/8 phosphorylation levels. Prolonged interaction of CML cells with the stromal cells in the presence of IM resulted in the acquisition of stroma-free chemoresistance to IM treatment. However, inhibition of actin cytoskeleton, ERK1/2 and SMAD signaling abrogated the chemoresistance acquisition and sensitized the chemoresistant CML cells to IM induced apoptosis.
Nonlocal Effects and Slip Heat Flow in Nanolayers
Authors: Zhu Chuan-Yong , You Wei , Li Zeng-Yao
Published: August 2017

Guyer-Krumhansl (G-K) equation is a promising macroscopic model to explore heat transport in nanoscale. In the present work, a new nonlocal characteristic length is proposed by considering the effects of heat carriers-boundaries interactions to modify the nonlocal term in G-K equation, and a slip heat flux boundary condition is developed based on the local mean free path of heat carriers. Then an analytical solution for heat flux across 2-D nanolayers and an in-plane thermal conductivity model are obtained based on the modified G-K equation and the slip heat flux boundary. The predictions of the present work are in good agreement with our numerical results of direct simulation Monte Carlo (DSMC) for argon gas nanolayer and the available experimental data for silicon thin layers. The results of this work may provide theoretical support for actual applications of G-K equation in predicting the thermal transport properties of nanolayers.
Microbial communities in peatlands along a chronosequence on the Sanjiang Plain, China
Authors: Zhou Xue , Zhang Zhenqing , Tian Lei , Li Xiujun , Tian Chunjie
Published: August 2017

Microbial communities play crucial roles in the global carbon cycle, particularly in peatland ecosystems under climate change. The peatlands of the Sanjiang Plain could be highly vulnerable to global warming because they are mainly located at the southern limit of northern peatlands. In this study, the alpha diversity and composition of bacterial communities in three different minerotrophic fens along a chronosequence were investigated. We captured a rich microbial community that included many rare operational taxonomic units (OTUs) but was dominated by a few bacterial classes that have frequently been detected in other peatland ecosystems. Notably, a large diversity of methanotrophs affiliated with Alpha- and Gammaproteobacteria was also detected. Bacterial alpha diversity and composition varied as a function of peat depth and its associated physical-chemical properties, such as total carbon, total nitrogen, pH and bulk density. We also found that bacterial community turnover (beta diversity) to be significantly correlated with soil age, whereas bacterial alpha diversity was not.
Branched polyethylenimine-functionalized carbon dots as sensitive and selective fluorescent probes for N-acetylcysteine via an off–on mechanism
Authors: Liu Hui , Li Rong Sheng , Zhou Jun , Huang Cheng Zhi
Published: August 2017

A novel fluorescence (FL) analytical method to determineN-acetylcysteine (NAC) was established by using a branched polyethyleneimine-functionalized carbon dot fluorescent system involving FL quenching by Cu2+and subsequent FL recovery upon addition of NAC.
Evolution of nanostructured single-phase CoSb3 thin films by low-energy ion beam induced mixing and their thermoelectric performance
Authors: Bala Manju , Gupta Srashti , Srivastava Sanjeev K. , Amrithapandian Sankarakumar , Tripathi Tripurari S. , Tripathi Surya K. , Dong Chung-Li , Chen Chi-Liang , Avasthi Devesh K. , Asokan Kandasami
Published: August 2017

We report that a nanostructured CoSb3 thin film in a single phase can be synthesized by ion beam processing of Co/Sb bilayer thin films with better thermoelectric properties.
Using a non-spin flip model to rationalize the irregular patterns observed in the activation of the C–H and Si–H bonds of small molecules by CpMCO (M = Co, Rh) complexes
Authors: Castro Guadalupe , Colmenares Fernando
Published: August 2017

Irregularities observed in activation reactions of the C–H and Si–H bonds by CpCoCO and CpRhCO are explained in terms of a two-step reaction scheme involving radical species.
Synthesis, characterisation and in vitro cytotoxicity of mixed ligand Pt(ii) oxadiazoline complexes with hexamethylenetetramine and 7-nitro-1,3,5-triazaadamantane
Authors: Sieste Stefanie , Lifincev Irina , Stein Nina , Wagner Gabriele
Published: August 2017

The synthesis, spectroscopic and DFT-computational characterisation of trans-Pt(ii) oxadiazoline complexes is described. Some are more cytotoxic in vitro than cisplatin with the human cancer cell lines HeLa and A549.
Enhanced photocatalytic reduction activity of uranium(vi) from aqueous solution using the Fe2O3–graphene oxide nanocomposite
Authors: Guo Yadan , Guo Yiqin , Wang Xuegang , Li Peng , Kong Liuwei , Wang Guanghui , Li Xiaomeng , Liu Yunhai
Published: August 2017

Photocatalytic technologies are a potential solution for remediation of radioactive wastewater, including the reduction of radioactive hexavalent uranium, which is commonly found in wastewater from the nuclear industry.
Improved detection sensitivity for heavy trace elements using a miniature laser ablation ionisation mass spectrometer
Authors: Wiesendanger R. , Tulej M. , Riedo A. , Frey S. , Shea H. , Wurz P.
Published: August 2017

Detecting heavy trace elements with a miniature laser spectrometer on a lunar meteorite.
Relation entre le corps vécu et le corps vivant après un effort et une procédure de récupération par immersion en eau froide ou passive chez des joueuses de handball
Authors: Tourny Claire , Castres Ingrid , Tabben Montassar , L’Hermette Maxime , Ghoul Nihel , Andrieu Bernard , Coquart Jérémy
Published: August 2017

L’objectif de cette étude est d’établir les afférences entre le corps vécu et le corps vivant durant deux types de récupération après un entraînement chez des joueuses de handball. Huit joueuses évoluant en championnat de France de niveau national 3 ont participé à l’étude. Toutes réalisaient de manière aléatoire une récupération passive et une récupération en immersion en eau froide après un entraînement. Durant les périodes de récupération, les sensations corporelles et certaines données physiologiques étaient relevées. De plus, une analyse deverbatimpost 24 h était mise en place. Les résultats révèlent un puissant lien entre le corps vivant et le corps vécu. De plus, il pourrait être utile d’identifier les individus « répondants » en prenant en compte le corps vécu.
Diastereoselective Lithiation of N-Benzyl Pyrroloimidazolones Derived from l-Proline Hydantoin
Authors: Emberson Kassandra , Tran Ngan , Metallinos Costa
Published: August 2017

An N-benzyl pyrroloimidazolone derived from l-proline hydantoin undergoes asymmetric lithiation with n-BuLi/TMEDA in toluene to give products of electrophile quench (E+) that range from 87:13 to 91:9 diastereomeric ratio (dr). All products appear to have the same relative stereochemistry as determined by transmetalation of benzylic stannanes, which gave identical major diastereomers for several products as to what was observed by direct lithiation–substitution of the starting material. X-Ray crystallography of the major diastereomer of the benzophenone adduct established (R)-configuration at the benzylic center, i.e., anti stereochemistry with respect to the imidazolone. Lithiation of a selectively deuterated analogue of the starting material according to the optimized conditions, followed by benzophenone quench, gave diastereomeric products with far lower selectivity (53:47 dr) than lithiation of the non-deuterated analogue (91:9 dr) owing to a large primary kinetic isotope effect. These preliminary results imply that metalation of the N-benzyl pyrroloimidazolone may follow an asymmetric deprotonation pathway to give a benzylic carbanion that retains its configuration during electrophile quench.
Persistent luminescence nanothermometers
Authors: Martín Rodríguez Emma , López-Peña Gabriel , Montes Eduardo , Lifante Ginés , García Solé José , Jaque Daniel , Diaz-Torres Luis Armando , Salas Pedro
Published: August 2017

Persistent phosphorescence nanoparticles emitting in the red and near-infrared spectral regions are strongly demanded as contrast nanoprobes for autofluorescence free bioimaging and biosensing. In this work, we have developed Sr4Al14O25:Eu2+, Cr3+, Nd3+ nanopowders that produce persistent red phosphorescence peaking at 694 nm generated by Cr3+ ions. This emission displays temperature sensitivity in the physiological temperature range (20–60 °C), which makes these nanoparticles potentially useful as fluorescence (contactless) nanothermometers operating without requiring optical excitation. Nd3+ ions, which act as shallow electron traps for the red Cr3+ persistent emission, also display infrared emission bands, extending the fluorescence imaging capability to the second biological window. This unique combination of properties makes these nanoparticles multifunctional luminescent probes with great potential applications in nanomedicine.
Scalable simple liquid deposition techniques for the enhancement of light absorption in thin films: Distributed Bragg reflectors coupled to 1D nanoimprinted textures
Authors: Brudieu B. , Gozhyk I. , Clements W. R. , Mazoyer S. , Gacoin T. , Teisseire J.
Published: August 2017

Light trapping within a light absorbing medium is a key to highly efficient thin film solar cells. We propose a large-scale procedure based on materials with low absorption for the fabrication of combined Distributed Bragg Reflector (DBR) and grating light trapping structures. Using Rigorous Coupled Wave Analysis (RCWA) numerical simulations we designed a combined DBR and 1D grating structure allowing to significantly improve the absorption in a aSi:H film as thin as 100 nm. The optimized light trapping structure was fabricated. The enhancement of light absorption in thin aSi:H film was experimentally proven and discussed quantitatively with respect to the theoretical expectations.
Scalar transport and the validity of Damköhler’s hypotheses for flame propagation in intense turbulence
Authors: Nivarti Girish V. , Cant R. Stewart
Published: August 2017

The turbulent burning velocity of premixed flames is sensitive to the turbulence intensity of the unburned mixture. Premixed flame propagation models that incorporate these effects of turbulence rest on either of the two hypotheses proposed by Damköhler. The first hypothesis applies to low-intensity turbulence that acts mainly to increase the turbulent burning velocity by increasing the flame surface area. The second hypothesis states that, at sufficiently high intensities of turbulence, the turbulent burning velocity is governed mainly by enhanced diffusivity. Most studies to date have examined the validity of the first hypothesis under increasingly high intensities of turbulence. In the present study, the validity of Damköhler’s second hypothesis is investigated. A range of turbulence intensities is addressed by means of direct numerical simulations spanning the “flamelet” and “broken reaction zones” regimes. The validity of Damköhler’s second hypothesis is found to be strongly linked to the behaviour of turbulent transport within the flame.
Kinetic energy offsets for multicharged ions from an electron beam ion source
Authors: Kulkarni D. D. , Ahl C. D. , Shore A. M. , Miller A. J. , Harriss J. E. , Sosolik C. E. , Marler J. P.
Published: August 2017

Using a retarding field analyzer, we have measured offsets between the nominal and measured kinetic energy of multicharged ions extracted from an electron beam ion source (EBIS). By varying source parameters, a shift in ion kinetic energy was attributed to the trapping potential produced by the space charge of the electron beam within the EBIS. The space charge of the electron beam depends on its charge density, which in turn depends on the amount of negative charge (electron beam current) and its velocity (electron beam energy). The electron beam current and electron beam energy were both varied to obtain electron beams of varying space charge and these were related to the observed kinetic energy offsets for Ar4+ and Ar8+ ion beams. Knowledge of these offsets is important for studies that seek to utilize slow, i.e., low kinetic energy, multicharged ions to exploit their high potential energies for processes such as surface modification. In addition, we show that these offsets can be utilized to estimate the effective radius of the electron beam inside the trap.
Efficient algorithms for large-scale quantum transport calculations
Authors: Brück Sascha , Calderara Mauro , Bani-Hashemian Mohammad Hossein , VandeVondele Joost , Luisier Mathieu
Published: August 2017

Massively parallel algorithms are presented in this paper to reduce the computational burden associated with quantum transport simulations from first-principles. The power of modern hybrid computer architectures is harvested in order to determine the open boundary conditions that connect the simulation domain with its environment and to solve the resulting Schrödinger equation. While the former operation takes the form of an eigenvalue problem that is solved by a contour integration technique on the available central processing units (CPUs), the latter can be cast into a linear system of equations that is simultaneously processed by SplitSolve, a two-step algorithm, on general-purpose graphics processing units (GPUs). A significant decrease of the computational time by up to two orders of magnitude is obtained as compared to standard solution methods.
Unsteady flow of a thixotropic fluid in a slowly varying pipe
Authors: Croudace Andrew I. , Pritchard David , Wilson Stephen K.
Published: August 2017

We analyse the unsteady axisymmetric flow of a thixotropic or antithixotropic fluid in a slowly varying cylindrical pipe. We derive general perturbation solutions in regimes of small Deborah numbers, in which thixotropic or antithixotropic effects enter as perturbations to generalised Newtonian flow. We present results for the viscous Moore–Mewis–Wagner model and the viscoplastic Houška model, and we use these results to elucidate what can be predicted in general about the behaviour of thixotropic and antithixotropic fluids in lubrication flow. The range of behaviour we identify casts doubt on the efficacy of model reduction approaches that postulate a generic cross-pipe flow structure.
Magnetic phase diagram of Co(Cr1−xAlx)2O4 (x = 0.0–1.0)
Authors: Padam R. , Sarkar T. , Mathieu R. , Thota S. , Pal D.
Published: August 2017

We report the role of Al substitution in the magnetic properties of spinel CoCr2O4 by means of temperature dependent dc and ac magnetization and heat capacity measurements. Various compositions (0.0 ≤ x ≤ 1.0) of polycrystalline Co(Cr1-xAlx)2O4 samples have been prepared by sol-gel processing and their crystal structure was investigated by X-ray diffraction which was found to crystallize in the normal cubic spinel structure. For x ≤ 0.1, the system exhibits multiple magnetic orderings (long range ferrimagnetic ordering TC, spin-spiral ordering TS, and lock-in transition TL), similar to that of the parent compound, CoCr2O4. However, all the compositions between x = 0.1 and 0.5 exhibit long range ferrimagnetic ordering below TC and also a short range order at low temperature. Spin-glass like ordering was noticed between x = 0.6 and 0.8 due to the diluted B-site occupancy, whereas the end compound CoAl2O4 (x = 1.0) shows antiferromagnetic behavior. On the basis of these results, we propose a magnetic phase diagram for the Co(Cr1-xAlx)2O4 series as a function of the Al content (x) and measuring temperature (T).
InAs/GaSb type-II superlattice infrared detectors: Future prospect
Authors: Rogalski A. , Martyniuk P. , Kopytko M.
Published: August 2017

Investigations of antimonide-based materials began at about the same time as HgCdTe ternary alloys—in the 1950s, and the apparent rapid success of their technology, especially low-dimensional solids, depends on the previous five decades of III-V materials and device research. However, the sophisticated physics associated with the antimonide-based bandgap engineering concept started at the beginning of 1990s gave a new impact and interest in development of infrared detector structures within academic and national laboratories. The development of InAs/GaSb type-II superlattices (T2SLs) results from two primary motivations: the perceived challenges of reproducibly fabricating high-operability HgCdTe focal plane arrays (FPAs) at reasonable cost and the theoretical predictions of lower Auger recombination for type T2SL detectors compared with HgCdTe. Second motivation—lower Auger recombination should be translated into a fundamental advantage for T2SL over HgCdTe in terms of lower dark current and/or higher operating temperature, provided other parameters such as Shockley-Read-Hall (SRH) lifetime are equal. InAs/GaSb T2SL photodetectors offer similar performance to HgCdTe at an equivalent cut-off wavelength, but with a sizeable penalty in operating temperature, due to the inherent difference in SRH lifetimes. It is predicted that since the future infrared (IR) systems will be based on the room temperature operation of depletion-current limited arrays with pixel densities that are fully consistent with background- and diffraction-limited performance due to the system optics, the material system with long SRH lifetime will be required. Since T2SLs are very much resisted in attempts to improve its SRH lifetime, currently the only material that meets this requirement is HgCdTe. Due to less ionic chemical bonding, III-V semiconductors are more robust than their II-VI counterparts. As a result, III-V-based FPAs excel in operability, spatial uniformity, temporal stability, scalability, producibility, and affordability—the so-called “ibility” advantages.
Purcell-enhancement of the radiative PL decay in perylenediimides by coupling with silver nanoparticles into waveguide modes
Authors: Signoretto Mattia , Zink-Lorre Nathalie , Martínez-Pastor Juan P. , Font-Sanchis Enrique , Chirvony Vladimir S. , Sastre-Santos Ángela , Fernández-Lázaro Fernando , Suárez Isaac
Published: August 2017

In this work, an interesting approach to enhance the coupling between excitons and plasmons is proposed by integrating highly luminescent perylenediimides (PDIs) and Ag metal nanoparticles (MNPs) in the core of a multilayer dielectric waveguide. The combination of the weak plasmonic coupling and the high scattering of MNPs gives rise to a significant improvement of the PDI photoluminescence and Purcell factor (PF) in forward-scattering geometry. Furthermore, when the PDI-MNP system is used as the core of a multilayer waveguide, a Purcell factor enhancement larger than 10 is observed, which is explained by an increase in the exciton-plasmon coupling under the light confinement in the waveguiding structure as compared to a single layer of PDI emitters.
TECHNOLOGY, TEAMWORK, RESPECT AND PERSISTENCE: INGREDIENTS OF SUCCESSFUL EXPLORATION IN THE ONSHORE OTWAY BASIN
Authors: Willink R.J. , Lovibond R.
Published: August 2017

Origin Energy Resources Limited has been an active explorer of the onshore Otway Basin in southeastern Australia for over a decade. Since 1989, the company has acquired 1,893 km and 358 sq km of 2D and 3D seismic data respectively, and participated in the drilling of 21 exploration and appraisal wells, 18 of which it operated, at a net cost of over $25 million.The primary exploration targets have been fluvial sandstones developed axially in a series of elongate half grabens that formed in initial response to the separation of the continents of Australia and Antarctica in the Late Jurassic to Early Cretaceous. The most significant of these depocentres, in terms of established hydrocarbon potential, is the highly faulted, NW–SE trending Penola Trough where these reservoirs are informally referred to as the Sawpit Sandstone and the Pretty Hill Sandstone.As the company’s geological understanding of the Penola Trough improved over time, so its exploration efforts were rewarded with new commercial discoveries at Haselgrove, Haselgrove South and Redman, and through successful appraisal of Ladbroke Grove. With respect to the application of advanced technology, 2D and 3D seismic are now subjected to Prestack Depth Migration to improve imaging of the subsurface, and Amplitude Versus Offset, Seismic Variance, Seismic Attribute, Fault Analysis and 3D Visualisation processing and/or software are also used in an integrated manner to facilitate interpretation of these data sets. Nuclear magnetic resonance logs are run in most wells to characterise gas-bearing reservoirs.Technology, respect and persistence have all played key roles in optimising the exploration process. So too have corporate teamwork and collaborative research with representatives from academic institutions and government agencies, and with industry consultants and contractors. The complex interplay between many of these success factors is illustrated by way of a case history, specifically that of the discovery and commercialisation of a low quality gas resource at Ladbroke Grove.In the fullness of time, the company is confident that further exploration success in the onshore Otway Basin will see new market opportunities addressed in terms of both gas and electricity supply. It is also hopeful that oil will eventually be found in commercial quantities.
BARRAMUNDI–1: A CASE HISTORY IN FRACTURE ANALYSIS AND SEAL INTEGRITY IN THE BASS BASIN
Authors: Crist R.P. , Conolly J.R. , Robinson L.D.
Published: August 2017

Barramundi–1 was drilled to test a faulted rollover structure with thick potential reservoir sands in the top Eocene Eastern View Coal Measures. A structure-wide AVO anomaly was mapped corresponding to these sands and this suggested the presence of a valid hydrocarbon trap.Barramundi–1 reached a total depth of 2,100 m on October 2 1999 after penetrating a thick reservoir sand sequence in the Eastern View Coal Measures within the T27/P permit operated by GLOBEX Far East.No significant hydrocarbons were encountered. Log analysis showed that large borehole breakouts occur below 1,400 m in thick Eastern View sands and background gas was observed to decrease. Dipole Sonic Imager (DSI) logs also showed that the amplitude of the fast shear wave event was attenuated from 1,250–1,450 m and was erratic in amplitude below this depth.The Compressional Velocity (Vp) to Shear Wave Velocity (Vs) ratios showed large variations over short intervals in the break out zones.It was concluded that Barramundi–1 failed to contain commercial hydrocarbons due to the seal failure caused by late Tertiary movement which has manifested itself both as fractures and faults, with a principal stress axis that trends northeast–southwest.An AVO anomaly mapped across the Barramundi structure has probably been caused by a combination of lithological and stress anisotropy in thick Eastern View sands at depths below 1,500 m, as observed by ovalisation occurring on the Caliban log analysis.It was concluded that the stresses would add to anisotropic effects in the rocks and consequently direct hydrocarbon detection methods such as AVO have to be used with caution.The central Bass Basin has generated both oil and gas. More wells need to be analysed using seal integrity methods in order to fully determine the reason for the failed trapping mechanism at Barramundi. This could eventually lead to a fault seal model that would allow exploration to successfully continue.
HYDROCARBON PROSPECTIVITY OF THE DEEPWATER GIPPSLAND BASIN, VICTORIA, AUSTRALIA
Authors: Bernecker T. , Woollands M.A. , Wong D. , Moore D.H. , Smith M.A.
Published: August 2017

After 35 years of successful exploration and development, the Gippsland Basin is perceived as a mature basin. Several world class fields have produced 3.6 billion (109) BBL (569 GL) oil and 5.2 TCF (148 Gm3) gas. Without additional discoveries, it is predicted that further significant decline in production will occur in the next decade.However, the Gippsland Basin is still relatively underexplored when compared to other prolific hydrocarbon provinces. Large areas are undrilled, particularly in the eastern deepwater part of the basin. Here, an interpretation of new regional aeromagnetic and deep-water seismic data sets, acquired through State and Federal government initiatives, together with stratigraphic, sedimentological and source rock maturation modelling studies have been used to delineate potential petroleum systems.In the currently gazetted deepwater blocks, eight structural trapping trends are present, each with a range of play types and considerable potential for both oil and gas. These include major channel incision plays, uplifted anticlinal and collapsed structures that contain sequences of marine sandstones and shales (deepwater analogues of the Marlin and Turrum fields), as well as large marine shale-draped basement horsts.The study has delineated an extensive near-shore marine, lower coastal plain and deltaic facies association in the Golden Beach Subgroup. These Late Cretaceous strata are comparable to similar facies of the Tertiary Latrobe Siliciclastics and extend potential source rock distribution beyond that of previous assessments. In the western portion of the blocks, overburden is thick enough to drive hydrocarbon generation and expulsion. The strata above large areas of the source kitchen generally dip to the north and west, promoting migration further into the gazetted areas.Much of the basin’s deepwater area, thus, shares the deeper stratigraphy and favourable subsidence history of the shallow water producing areas. Future exploration and production efforts will, however, be challenged by the 200–2500 m water-depths and local steep bathymetric gradients, which affect prospect depth conversion and the feasibility of development projects in the case of successful exploration.
FRACTURE FORMATION AND FLUID FLOW IN THE PALM VALLEY GAS FIELD, CENTRAL AUSTRALIA
Authors: Hamilton P.J. , Eadington P.J. , Lisk M. , Milne N.A.
Published: August 2017

Palaeo-fluid flow in the fracture network in the Palm Valley gas field (Amadeus Basin, central Australia) was investigated using fluid inclusion, isotopic and petrographic methods. The Ordovician Pacoota and Stairway Sandstone reservoir rocks have exceedingly low matrix porosity and permeability and economic gas flow rates, therefore, depend on the fracture network.Pre-fracture cementation of the matrix involved precipitation of pyrite, haematite, chlorite, illite and quartz. However, matrix cementation, as well as the fracture mineralisation, is now dominated by barite, ankerite and quartz. This indicates that subsequent to being fractured, connectivity between matrix porosity and fractures allowed invasion of the host sandstones by mineralising fluids from the fracture network. Fluid inclusion palaeo-temperature analyses indicate temperatures of 90–115°C prevailed at the time of formation of these minerals which was contemporaneous with maximum burial estimated to have occurred during the Alice Springs orogeny at ~340–240 Ma.Aqueous fluids in the sandstones were derived from three sources. Connate waters comprise one source and were parental to pre-fracture diagenetic minerals. The reservoir was accessed by two other fluids via the fracture network. Basinal brines comprise one source, whilst low salinity waters of surface meteoric origin comprise the other. One component of the basinal brine had had prior contact with Precambrian Bitter Springs Formation evaporites whilst another had been in contact with rocks characterised by high barium contents and radiogenic strontium isotope ratios. The total vertical component of fluid flow appears to have been ~7–8 km.Hydrocarbon migration was in part synchronous with fracture development and was accompanied by migration of basinal brines. Liquid hydrocarbons and wet gas migrated during cementation of the fractures. Temperatures continued to rise and dry gas was generated which displaced the wet gas now only observed in fluid inclusions in the mineral cements.