bluuebunny/crossref_metadata_2025 huggingface dataset:
Interaction of lipopolysaccharides at intermolecular sites of the periplasmic Lpt transport assembly
Authors: Laguri Cedric , Sperandeo Paola , Pounot Kevin , Ayala Isabel , Silipo Alba , Bougault Catherine M. , Molinaro Antonio , Polissi Alessandra , Simorre Jean-Pierre
Published: August 2017

Transport of lipopolysaccharides (LPS) to the surface of the outer membrane is essential for viability of Gram-negative bacteria. Periplasmic LptC and LptA proteins of the LPS transport system (Lpt) are responsible for LPS transfer between the Lpt inner and outer membrane complexes. Here, using a monomeric E. coli LptA mutant, we first show in vivo that a stable LptA oligomeric form is not strictly essential for bacteria. The LptC-LptA complex was characterized by a combination of SAXS and NMR methods and a low resolution model of the complex was determined. We were then able to observe interaction of LPS with LptC, the monomeric LptA mutant as well as with the LptC-LptA complex. A LptC-LPS complex was built based on NMR data in which the lipid moiety of the LPS is buried at the interface of the two β-jellyrolls of the LptC dimer. The selectivity of LPS for this intermolecular surface and the observation of such cavities at homo- or heteromolecular interfaces in LptC and LptA suggests that intermolecular sites are essential for binding LPS during its transport.
Purification of Dye-stuff Contained Wastewater by a Hybrid Adsorption-Periphyton Reactor (HAPR): Performance and Mechanisms
Authors: Feng Yanfang , Xue Lihong , Duan Jingjing , Dionysiou Dionysios D. , Chen Yudong , Yang Linzhang , Guo Zhi
Published: August 2017

Abstracts

The aim of this study was to develop an environmental-benign bio-measure that could be used to purify dye-contaminated wastewater. Herein, a hybrid adsorption-periphyton reactor (HAPR), combining a bioadsorbent based adsorption unit and a periphyton-based photo-bioreactor (PPBR), was built and applied for the first time. Firstly, an efficient bioadsorbent, i.e, microwave-activated swede rape hull (MSRH), was produced, characterized and applied in an adsorption column, to pretreat methylene blue (MB) wastewater with high concentration (~100 mg L−1 or higher). Thereafter, the effluent of adsorption column, with lower dye concentration (~0.5 mg L−1), was collected and further purified by PPBR. Results showed that dye removal efficiency by HAPR was 99.95% (from 200 mg L−1 to 0.1 mg L−1 or lower). Decolorization mechanisms by PPBR, included adsorption process by extracellular polymeric substances (EPS) on the surface of periphyton and degradation process. The study showed that HAPR was a novel, environmental friendly, efficient and promising dye-purification method and deserved further attention in future investigation.
A rare genetic variant of BPIFB4 predisposes to high blood pressure via impairment of nitric oxide signaling
Authors: Vecchione Carmine , Villa Francesco , Carrizzo Albino , Spinelli Chiara Carmela , Damato Antonio , Ambrosio Mariateresa , Ferrario Anna , Madonna Michele , Uccellatore Annachiara , Lupini Silvia , Maciag Anna , Ryskalin Larisa , Milanesi Luciano , Frati Giacomo , Sciarretta Sebastiano , Bellazzi Riccardo , Genovese Stefano , Ceriello Antonio , Auricchio Alberto , Malovini Alberto , Puca Annibale Alessandro
Published: August 2017

BPIFB4 is associated with exceptional longevity: four single-nucleotide polymorphisms distinguish the wild-type form from a longevity-associated variant conferring positive effects on blood pressure. The effect of a rare variant (RV; allele frequency, 4%) on blood pressure is unknown. Here, we show that overexpression of RV-BPIFB4 in ex-vivo mouse vessels impairs phosphorylation of endothelial nitric oxide synthase (eNOS), blunting acetylcholine-evoked vasorelaxation; in vivo, virally mediated overexpression of RV-BPIFB4 increases blood pressure, an action absent in eNOS-deficient mice. In humans, we found RV carriers to have increased diastolic blood pressure, a finding that was more marked in subjects on anti-hypertensive medication; moreover, recombinant RV-BPIFB4 protein impaired eNOS function in ex-vivo human vessels. Thus, RV-BPIFB4 acts directly on blood pressure homeostasis and may represent a novel biomarker of vascular dysfunction and hypertension.
The naphthalene catabolic protein NahG plays a key role in hexavalent chromium reduction in Pseudomonas brassicacearum LZ-4
Authors: Huang Haiying , Tao Xuanyu , Jiang Yiming , Khan Aman , Wu Qi , Yu Xuan , Wu Dan , Chen Yong , Ling Zhenmin , Liu Pu , Li Xiangkai
Published: August 2017

Soil contamination by PAH and heavy metals is a growing problem. Here, we showed that a new isolate, Pseudomonas brassicacearum strain LZ-4, can simultaneously degrade 98% of 6 mM naphthalene and reduce 92.4% of 500 μM hexavalent chromium [Cr (VI)] within 68 h. A draft genome sequence of strain LZ-4 (6,219,082 bp) revealed all the genes in the naphthalene catabolic pathway and some known Cr (VI) reductases. Interestingly, genes encoding naphthalene pathway components were upregulated in the presence of Cr (VI), and Cr (VI) reduction was elevated in the presence of naphthalene. We cloned and expressed these naphthalene catabolic genes and tested for Cr (VI) reduction, and found that NahG reduced 79% of 100 μM Cr (VI) in 5 minutes. Additionally, an nahG deletion mutant lost 52% of its Cr (VI) reduction ability compared to that of the wild-type strain. As nahG encodes a salicylate hydroxylase with flavin adenine dinucleotide (FAD) as a cofactor for electron transfer, Cr (VI) could obtain electrons from NADH through NahG-associated FAD. To the best of our knowledge, this is the first report of a protein involved in a PAH-degradation pathway that can reduce heavy metals, which provides new insights into heavy metal-PAH contamination remediation.
Creating the Functional Single-Ring GroEL-GroES Chaperonin Systems via Modulating GroEL-GroES Interaction
Authors: Illingworth Melissa , Ellis Holly , Chen Lingling
Published: August 2017

Chaperonin and cochaperonin, represented by E. coli GroEL and GroES, are essential molecular chaperones for protein folding. The double-ring assembly of GroEL is required to function with GroES, and a single-ring GroEL variant GroELSR forms a stable complex with GroES, arresting the chaperoning reaction cycle. GroES I25 interacts with GroEL; however, mutations of I25 abolish GroES-GroEL interaction due to the seven-fold mutational amplification in heptameric GroES. To weaken GroELSR-GroES interaction in a controlled manner, we used groES7, a gene linking seven copies of groES, to incorporate I25 mutations in selected GroES modules in GroES7. We generated GroES7 variants with different numbers of GroESI25A or GroESI25D modules and different arrangements of the mutated modules, and biochemically characterized their interactions with GroELSR. GroES7 variants with two mutated modules participated in GroELSR–mediated protein folding in vitro. GroES7 variants with two or three mutated modules collaborated with GroELSR to perform chaperone function in vivo: three GroES7 variants functioned with GroELSR under both normal and heat-shock conditions. Our studies on functional single-ring bacterial chaperonin systems are informative to the single-ring human mitochondrial chaperonin mtHsp60-mtHsp10, and will provide insights into how the double-ring bacterial system has evolved to the single-ring mtHsp60-mtHsp10.
Global distribution of clay-size minerals on land surface for biogeochemical and climatological studies
Authors: Ito Akihiko , Wagai Rota
Published: August 2017

Clay-size minerals play important roles in terrestrial biogeochemistry and atmospheric physics, but their data have been only partially compiled at global scale. We present a global dataset of clay-size minerals in the topsoil and subsoil at different spatial resolutions. The data of soil clay and its mineralogical composition were gathered through a literature survey and aggregated by soil orders of the Soil Taxonomy for each of the ten groups: gibbsite, kaolinite, illite/mica, smectite, vermiculite, chlorite, iron oxide, quartz, non-crystalline, and others. Using a global soil map, a global dataset of soil clay-size mineral distribution was developed at resolutions of 2' to 2° grid cells. The data uncertainty associated with data variability and assumption was evaluated using a Monte Carlo method, and validity of the clay-size mineral distribution obtained in this study was examined by comparing with other datasets. The global soil clay data offer spatially explicit studies on terrestrial biogeochemical cycles, dust emission to the atmosphere, and other interdisciplinary earth sciences.
A general polymer-assisted strategy enables unexpected efficient metal-free oxygen-evolution catalysis on pure carbon nanotubes
Authors: Zhang You , Fan Xuliang , Jian Junhua , Yu Dingshan , Zhang Zishou , Dai Liming
Published: August 2017

A conceptually new and general polymer-assisted strategy was proposed to enable unexpected efficient metal-free oxygen-evolution catalysis on pure carbon nanotubes.
New application of tiplaxtinin as an effective FtsZ-targeting chemotype for an antimicrobial study
Authors: Sun Ning , Zheng Yuan-Yuan , Du Ruo-Lan , Cai Sen-Yuan , Zhang Kun , So Lok-Yan , Cheung Kwan-Choi , Zhuo Chao , Lu Yu-Jing , Wong Kwok-Yin
Published: August 2017

Tiplaxtinin exhibits an excellent cell division inhibitory effect with potent antibacterial activity through interacting with FtsZ.
Changes in the heavy metal distributions in whole soil and aggregates affected by the application of alkaline materials and phytoremediation
Authors: Xu Lei , Cui Hongbiao , Zheng Xuebo , Zhou Jun , Zhang Wenhui , Liang Jiani , Zhou Jing
Published: August 2017

The combined effect of alkaline materials and plants on the distribution of copper and cadmium in whole soil and aggregates was explored by a 3 yearin situexperiment.
Phosphorus recovery as ferrous phosphate (vivianite) from wastewater produced in manufacture of thin film transistor-liquid crystal displays (TFT-LCD) by a fluidized bed crystallizer (FBC)
Authors: Priambodo Ricky , Shih Yu-Jen , Huang Yao-Hui
Published: August 2017

In this investigation, fluidized bed crystallization (FBC) is utilized to treat phosphorus wastewater that is produced by the manufacture of thin film transistor-liquid crystal displays (TFT-LCD).
Gold nanoparticle bioconjugates labelled with 211At for targeted alpha therapy
Authors: Dziawer L. , Koźmiński P. , Męczyńska-Wielgosz S. , Pruszyński M. , Łyczko M. , Wąs B. , Celichowski G. , Grobelny J. , Jastrzębski J. , Bilewicz A.
Published: August 2017

Gold nanoparticles labeled with 211At are very effective in radionuclide therapy.
PTMAc-PEG-PTMAc hydrogel modified by RGDC and hyaluronic acid promotes neural stem cells' survival and differentiation in vitro
Authors: Yang Ruirui , Xu Caixia , Wang Tao , Wang Yuanqi , Wang Jingnan , Quan Daping , Deng David Y. B.
Published: August 2017

The enhancement of the biological properties of hydrogels by surface modifying with bioactive molecules is of great significance, especially for the treatment of central nervous system injury by combining engrafted cells.
Encapsulation of transition metal dichalcogenides crystals with room temperature plasma deposited carbonaceous films
Authors: Mahyavanshi Rakesh D. , Kalita Golap , Singh Rupesh , Kondo Masaharu , Dewa Takehisa , Kawahara Toshio , Umeno Masayoshi , Tanemura Masaki
Published: August 2017

Demonstrated encapsulation of dichalcogenides layer by coating a carbonaceous film by surface wave plasma technique.
A first-principles study of anionic (S) and cationic (V/Nb) doped Sr2Ta2O7 for visible light photocatalysis
Authors: Peng Yuman , Ma Zuju , Hu Junjie , Wu Kechen
Published: August 2017

In order to utilize the visible light to catalyze water, UV-active Sr2Ta2O7 is engineered via co-doping of S and V/Nb to shift the valence band maximum upward and conduction band minimum downward by approximately 1 eV, respectively.
Gate modulated and enhanced optoelectronic performance of MoSe2 and CVD-grown MoS2 heterojunctions
Authors: Yang Yujue , Huo Nengjie , Li Jingbo
Published: August 2017

MoSe2 and CVD-grown MoS2 heterojunctions displayed significant gate-modulated photovoltaic effect and dramatically improved photo-responsivity of 350 A W−1.
Polyazomethines and their acid–base interactions with Nafion and Nafion–imidazole membranes for efficient fuel cells
Authors: Malinowski Marek , Iwan Agnieszka , Tazbir Igor , Boharewicz Bartosz , Sikora Andrzej , Stafiniak Andrzej
Published: August 2017

We propose, for the first time, aromatic polyazomethines applied in polymer electrolyte membrane fuel cells (PEMFC) as tetrafluoroethylene-perfluoro-3,6-dioxa-4-methyl-7-octene-sulfonic acid copolymer (PFSA) membrane modifiers.
Fe3C@nitrogen doped CNT arrays aligned on nitrogen functionalized carbon nanofibers as highly efficient catalysts for the oxygen evolution reaction
Authors: Zhao Yufei , Zhang Jinqiang , Guo Xin , Fan Hongbo , Wu Wenjian , Liu Hao , Wang Guoxiu
Published: August 2017

Fe3C based catalysts are found to be one of the most promising electrocatalysts for the oxygen evolution reaction (OER).
Identification of relevant prognostic values of cytokeratin 20 and cytokeratin 7 expressions in lung cancer
Authors: Luo Hai-Tao , Liang Cai-Xia , Luo Rong-Cheng , Gu Wei-Guang
Published: August 2017

Lung cancer is one of the most common malignant tumors harmful to human health. Cytokeratin (CK) is highly conserved and differentiated related to the proliferation and differentiation of epithelial cells. The aim of the study was to explore expressions of CK20 and CK7 and corresponding prognostic values in patients with lung cancer. Our study included 258 cases of patients confirmed with lung cancer. Expressions of CK20 and CK7 mRNA and protein were detected using real-time quantitative PCR (qRT-PCR) and Western blot, respectively, followed by the performance of immunohistochemistry staining. Associations of CK20 and CK7 with the clinical parameters and prognosis of lung cancer patients were further analyzed. There were obvious differences regarding the positive expression of CK20 in different T stage, lymph node metastasis, invasion, size, and clinical stage subgroups; besides, significant differences in the positive expression of CK7 were also observed in subgroups of different sex, age, lymph node metastasis, invasion, and differentiation. Furthermore, effects of age, smoking, T stage, lymph node metastasis and invasion, size, and CK7 expressions were significant on the survival of patients (all P<0.05). Multivariate analysis revealed that lymph node metastasis, T stage, and CK7 expression were independent risk factors for poor prognosis of involved patients (all P<0.05), while age, smoking, and invasion had no marked relation to the survival time of patients with lung cancer (all P>0.05). Positive CK20 and CK7 expressions are detected in patients with lung cancer; positive expression of CK7 associated with pathological features of lymph node metastasis and T stage may be independent clinical parameters for poor prognosis of patients with lung cancer.
Highly Strained para-Phenylene-Bridged Macrocycles from Unstrained 1,4-Diketo Macrocycles
Authors: Merner Bradley , Mitra Nirmal , Merryman Caroline
Published: August 2017

The conversion of macrocyclic 1,4-diketones to highly strained para-phenylene rings has recently been reported by our laboratory. This synthetic strategy represents a non-cross-coupling-based approach to arene-bridged macrocycles, and an alternative to palladium- and nickel-mediated processes. In this Synpacts article we discuss the development of endgame aromatization protocols for the synthesis of increasingly strained arene systems, as well as potential advantages of the macrocyclic 1,4-diketone approach to selectively functionalized benzenoid macrocycles for future complexity building reactions.

1 Introduction

2 A Non-Cross-Coupling-Based Approach to Arene-Bridged Macro cycles

3 Macrocyclic 1,4-Diketones: Streamlined Synthesis and Size-­Dependent Diastereoselective Grignard Reactions

4 Dehydrative Aromatization Reactions: A Powerful Tool for Synthesizing Highly Strained para-Phenylene Units

5 Conclusion
4-Ethoxy-1,1,1-trifluoro-3-buten-2-one (ETFBO), a Versatile Precursor for Trifluoromethyl-Substituted Heteroarenes – a Short Synthesis of Celebrex® (Celecoxib)
Authors: Kirschning Andreas , Sommer Heiko , Braun Max , Schröder Benjamin
Published: August 2017

4-Ethoxy-1,1,1-trifluoro-3-buten-2-one (ETFBO) serves as a trifluoromethyl-containing building block for the preparation of trifluoromethyl-substituted thiophenes, furans, pyrrols, and piperazines. Key steps are an addition–elimination reaction to ETFBO followed by the thiazolium-catalyzed Stetter reaction. The scope of this chemistry was demonstrated in a new synthetic approach towards the COX-2 selective, nonsteroidal anti-inflammatory drug Celebrex® (celecoxib).
Realism, horror and the Gothic in Dracula and Thomas Hardy’s “The fiddler of the reels”
Authors: Senf Carol
Published: August 2017

Thomas Hardy (1840–1928) and Bram Stoker (1847–1912) were contemporaries as well as members of the same literary circles (Hardy often attended performances at the Lyceum Theater, which Stoker managed). The two are rarely compared, however, because Hardy is generally regarded as a writer of realistic fiction and as a poet while Stoker is remembered as the writer of Dracula as well as other Gothic works even though he actually wrote more romances. Realism, Horror and the Gothic in Dracula and “The Fiddler of the Reels” points to the fact that these two works are representative of the kinds of fiction created at the end of the nineteenth century and that both writers comment on the times in which they live. Specifically, both adapt a trope from traditional balladry, The Daemon Lover, to reveal that the forces of the primitive past continue to lurk beneath their progressive and confident present and emerge to influence the present. Their emphasis on the continued power of the past serves to criticize the overconfidence that was common at the turn of the twentieth century when England dominated the world in science, economics and industry. What the two writers created, however, is quite different, and exploring Hardy’s “The Fiddler of the Reels” and Dracula moves beyond these two works to reveal the extent to which the realistic fiction of the nineteenth century came to incorporate Gothic tropes and materials without becoming fully Gothic, as well as the fact that the Gothic often explores real social problems. Moreover, examining these two works also reveals how knowledge of science led to the emphasis on horror rather than terror in the Gothic of the twentieth and twenty-first centuries. Of particular relevance to students of the Gothic is the way this article explores a critical period in the evolution of the Gothic and points to the fact that the Gothic became increasingly domesticated at this time, a trend that continues to the present day. Students of Hardy’s fiction will be especially interested to read this exploration of a story that is rarely discussed even by Hardy experts, and students of Dracula will gain an additional appreciation of the fact that Stoker was influenced by what was happening around him when he wrote his best-known novel.
The role of indigenous peoples in combating climate change
Authors: Etchart Linda
Published: August 2017

Until the twenty-first century, indigenous peoples were viewed as victims of the effects of climate change, rather than as agents of environmental conservation. Representatives of indigenous peoples have in fact since 2008 been actively seeking a role in contributing to combating climate change through their participation in international environmental conferences, as well as by means of activism and political engagement at local and national levels. Using examples from the Amazonian region in the east of Ecuador, home to indigenous communities such as the Huaorani, Sápara and Sarayaku Kichwa originary peoples, this article argues that indigenous peoples, particularly forest dwellers, have a dual role in combating climate change. First, colonized forest peoples have continued to resist the occupation and deforestation of lands they have lived in for centuries; second, a number of indigenous forest communities have since the 1990s become aware of their responsibility to protect the forests in the interests of combating climate change. They have recognized the potential for their having decision-making power at a local and global level that may contribute to saving the planet. In the last 10 years indigenous peoples’ representatives have been collectively engaged in lobbying for inclusion in intergovernmental climate change negotiations and to have decision-making power at the United Nations. This comment calls for international support from governments and civil society from both North and South, at the United Nations and at other international fora, to uphold the rights of indigenous peoples—enshrined in international law—who wish to prevent incursions into their territory for the extraction of fossil fuels. Moreover, it calls on governments, (I)NGOs, and private companies engaged in the extractive industries, and in other processes of modernization and development, to respect the right of indigenous peoples not to develop and to choose for themselves the level of their integration into the global economy and polity. The choice not to develop, not to have access to the modern world through roads, for example, is itself a contribution to protecting the rainforest and reducing greenhouse gas emissions. This article draws on existing scholarly literature on the Ecuadorian Amazonian indigenous peoples, primary research among Huaorani and Sarayaku Kichwa communities of Eastern Ecuador 2016–2017, and documents from the United Nations Permanent Forum on Indigenous Issues (UNPFII) 26 April—6 May 2017. The aim is to provide policymakers, and those to whom they are accountable, with knowledge and understanding to improve decision-making in the interests of citizens and the environment.
Magnetic domain configuration of (111)-oriented LaFeO3 epitaxial thin films
Authors: Hallsteinsen I. , Moreau M. , Chopdekar R. V. , Christiansen E. , Nord M. , Vullum P.-E. , Grepstad J. K. , Holmestad R. , Selbach S. M. , Scholl A. , Arenholz E. , Folven E. , Tybell T.
Published: August 2017

In antiferromagnetic spintronics control of the domains and corresponding spin axis orientation is crucial for devices. Here we investigate the antiferromagnetic axis in (111)-oriented LaFeO3/SrTiO3, which is coupled to structural twin domains. The structural domains have either the orthorhombic a- or b-axis along the in-plane ⟨11¯0⟩ cubic directions of the substrate, and the corresponding magnetic domains have the antiferromagnetic axis in the sample plane. Six degenerate antiferromagnetic axes are found corresponding to the ⟨11¯0⟩ and ⟨112¯⟩ in-plane directions. This is in contrast to the biaxial anisotropy in (001)-oriented films and reflects how crystal orientation can be used to control magnetic anisotropy in antiferromagnets.
Enhanced optical, electrical, and mechanical characteristics of ZnO/Ag grids/ZnO flexible transparent electrodes
Authors: Wang Chen-Tao , Ting Chu-Chi , Kao Po-Ching , Li Shan-Rong , Chu Sheng-Yuan
Published: August 2017

This study demonstrates well-designed tri-layer flexible transparent conducting electrodes (TCEs), whose structure is ZnO (20 nm)/Ag grids (4, 6, 8, 10 nm)/ZnO (20 nm) (ZAZ), fabricated via thermal deposition. The optical, electrical, and mechanical characteristics of the proposed structure are improved compared to those of MoO3/Ag grids/MoO3 (MAM) electrodes. The transmittance at 550 nm, sheet resistance, and figure of merit of the proposed ZAZ electrodes with 6-nm silver grids are 78.58%, 9.3 Ω/square, and 9.6 × 10−3, respectively, which are better than those of MAM electrodes (66.25%, 9.7 Ω/square, and 1.6 × 10−3, respectively). It is found that the enhancement of the electrical characteristics of ZAZ can be ascribed to the improved crystallization of ZnO films. ZnO films with improved crystallization and a larger grain size can inhibit carriers from scattering at inter-grain boundaries. Based on a bending test, the strains of ZAZ electrodes under tension and compression were 0.616%, 0.633%, and those of MAM electrodes were 0.62% and 0.65%, respectively. The sheet resistance of the ZAZ structure increases significantly after 800 bending cycles, while that of the MAM structure increases significantly after only 200 bending cycles. These data indicate that ZAZ electrodes have significantly improved mechanical properties and durability compared to those of MAM electrodes in the bending test under both tensile and compressive stress. The proposed TCEs show good optical, electrical, and mechanical characteristics and have potential for application in optoelectronics.
A deep-level transient spectroscopy study of gamma-ray irradiation on the passivation properties of silicon nitride layer on silicon
Authors: Dong Peng , Yu Xuegong , Ma Yao , Xie Meng , Li Yun , Huang Chunlai , Li Mo , Dai Gang , Zhang Jian
Published: August 2017

Plasma-enhanced chemical vapor deposited silicon nitride (SiNx) films are extensively used as passivation material in the solar cell industry. Such SiNx passivation layers are the most sensitive part to gamma-ray irradiation in solar cells. In this work, deep-level transient spectroscopy has been applied to analyse the influence of gamma-ray irradiation on the passivation properties of SiNx layer on silicon. It is shown that the effective carrier lifetime decreases with the irradiation dose. At the same time, the interface state density is significantly increased after irradiation, and its energy distribution is broadened and shifts deeper with respect to the conduction band edge, which makes the interface states becoming more efficient recombination centers for carriers. Besides, C–V characteristics show a progressive negative shift with increasing dose, indicating the generation of effective positive charges in SiNx films. Such positive charges are beneficial for shielding holes from the n-type silicon substrates, i. e. the field-effect passivation. However, based on the reduced carrier lifetime after irradiation, it can be inferred that the irradiation induced interface defects play a dominant role over the trapped positive charges, and therefore lead to the degradation of passivation properties of SiNx on silicon.
Operational and safety aspects of drill stem testing—getting it right
Authors: Venugopal Shangkar
Published: August 2017

Drill stem testing (DST) is recognised by many operating oil and gas companies to be one of the most hazardous operations routinely undertaken. Well testing has a higher potential for loss of life, loss of assets, environmental catastrophe and budget overrun than any other time in the exploration operations. Therefore, it is of great importance to the industry that such operations are extremely well planned and executed.
Planning a DST is an extremely complex task and requires a great deal of experience. This paper provides an insight into the techniques and procedures that are used in all the major operational and safety aspects of oil and gas DST. It uses a structured approach to guide the reader through the various best practices that are required to effectively plan and implement a DST operation under just about any circumstances worldwide, onshore or offshore.
The project also includes design parameters for contingency conditions that were not normally present during equipment operations but could exist in emergency situations. Problems and solutions associated with perforation, adverse hole conditions, and high-pressure, high-temperature (HPHT) conditions are also presented. Additionally, this paper includes an overview on environmental requirements, which provides information associated with risk management and legislation.
Highlights and trends in exploration 2009
Authors: Wakelin-King Gordon
Published: August 2017

2009 saw an overall decrease from high activity from 2008, levelling off in the December quarter as the economy stabilised. Unsurprisingly, most activity was in offshore Western Australia and on coal seam methane (CSM) in Queensland. Highlights include: good results in the Carnarvon and Browse basins for Western Australian operators, interest in Karoon and Conoco-Phillips’ enigmatic Poseidon project, over 180 CSM exploration wells in Queenslandd, and a relatively busy year for Tasmania.
Western Australian seismic acquisition approached 10,000 km of 2D and 25,000 km2 of 3D for 38* wells and success rate around 50%. South Australia saw the highest conventional onshore drilling and seismic activity, with good results for 17 wells, while other states saw low activity in this sector. Victoria saw one offshore exploration well and no seismic. Tasmania also saw no new seismic, but saw four exploration wells and encouragement at Rockhopper–1. CSM is picking up in South Australia, and New South Wales saw continued high CSM activity in a historically low-activity region.
High success rates suggest two trends: explorers finding value in 3D seismic, and a ‘flight to quality’ as operating costs and poorer access to capital reinforce risk aversion among operators. Elsewhere, geothermal energy helped small cap investors satisfy their appetite for risk outside of the petroleum industry, and results will be watched with great interest.
*Numbers are from early public and departmental statistics and may be revised.
PESA industry review—2009 environmental update
Authors: Slater Sue
Published: August 2017

This paper provides a brief update on some of the key environmental issues that arose during 2009.
In Queensland, activity is dominated by coal seam gas projects and specifically coal seam gas (CSG) to liquefied natural gas (LNG) projects. Environmental milestones for these projects are discussed, and the State Government’s response policy and regulation development response is reviewed.
The progress of the more conventional LNG projects in Western Australia and the Northern Territory is also discussed. The final report on the mandated ten year review of the Environment Protection and Biodiversity Conservation Act 1999 was released in December 2009. Seventy-one recommendations were made, and some key recommendations related to our industry are discussed here.
Climate change has again dominated the media, with the United Nations Climate Change Conference held in Copenhagen in December 2009. In Queensland, the Government released a paper that presented a range of strategies and policies, building on a number of existing schemes and introducing new measures. Gas is identified as a key transitional fuel while low emission coal technology and emerging renewable energy sources are being developed. Greenhouse gas legislation is continuing to be developed across several states, but subordinate legislation is yet to be finalised. In Victoria, submissions on the Greenhouse Gas Geological Sequestration Regulations closed in October 2009, and the Greenhouse Gas Geological Sequestration Act 2008 came into effect on 1 December 2009. In March 2009, ten offshore acreage releases were made under the Commonwealth legislation; however, the closing date for submissions is dependent upon the development of the regulations. South Australia passed an Act amending the Petroleum and Geothermal Act 2000 on 1 October 2009 to allow geosequestration.
A number of reviews of the regulatory framework or the administrative systems associated with the upstream oil and gas sector have been completed in the last decade. All these reviews make similar findings and recommendations, and most recently the Jones Report, tabled in Western Australian Parliament on 12 August 2009, found that most key recommendations from previous reports and reviews had not been addressed or properly implemented. There seems to be little point in undertaking regulatory and system reviews that consistently make similar findings, if these findings are never addressed. The hurdles to implementation of key recommendations need to be identified, so that progress can be made in improving the approvals processes for the industry, and improving the environmental outcomes.
Changing petroleum engineering education to meet industry demands
Authors: Smith Lisa , Evans Brian
Published: August 2017

The Department of Petroleum Engineering at Curtin University had its inception in 1998. For the last 10 years, it lectured the Masters in petroleum engineering course to local Australian and international students, graduating more than 200 students. The rapid increase in the price of oil during 2006/7 saw a sudden and substantial growth in industry employment opportunities, which resulted in the department losing over half of its staff to industry. At the same time, the supply of local students reduced to less than 10% of those taking the course. This loss in both student numbers and staff at the same time threatened the department’s future, and resulted in the need for a new focus to return the department to stability.
A number of new initiatives were introduced, which included: bringing industry into the decision-making processes; introducing a new two-year Masters program to assist high quality migrant students obtain Australian permanent residency; increasing the advertising of petroleum engineering as a career option to schools and industry; linking with UNSW, UWA and Adelaide universities to establish a joint Masters program; introducing a new Bachelor’s degree in petroleum engineering; changing the block form of teaching to a semester-based form; and having the Commonwealth recognise the new Masters program for Commonwealth funding of Australian students as a priority pathway to a career as a petroleum engineer while the Bachelors program gathered momentum.
This paper maps the positive changes made during 2008/9, which led to a 100% increase in student numbers, a 50% increase in staff to stabilise teaching, a 400% increase in active PhD students, and industry projects to deliver an increasing stream of high quality, industry-ready, graduate petroleum engineers over the next 10–20 years into the current ageing population where the average age of a petroleum engineer is 51.
Commercially driven social benefit: a structured approach to Aboriginal engagement
Authors: Jones Craig
Published: August 2017

Most corporate approaches to engagement with Aboriginal Australians are determined by a tension between two poles: seeking access by minimal legal compliance or a form of enlightened charity known as corporate social responsibility which, in turn, is driven by a tension between the simple concept of charity and seeking a social licence to operate. Obviously companies require both legal access and a social licence to operate. The Santos model of Aboriginal engagement proposes community driven commerciality through a structured process that seeks to manage project risk in terms of cost, delay and legal action.
Importantly, Aboriginal engagement at Santos is about development of sustainable relations with Aboriginal communities and to contribute to those communities to, in turn, becoming sustainable.
Projects and legal compliance provide an opportunity for Aboriginal people and companies to sit at the table together. The development of the project to the operation phase allows the company and the community to plan for, and achieve sustainability in a mutually beneficial manner.
Unusual reservoir connectivity revealed by data integration at the Sunrise field
Authors: James Bruce , Bailey Wayne , Murray Andrew , Pelechaty Shane , Kaiko Alex , Li Jinfeng
Published: August 2017

The Sunrise gas-condensate field located in the Timor Sea is part of a planned liquefied natural gas (LNG) development. It is a broad, low-relief structure covering approximately 900 km2 with two main reservoirs in the Plover Formation. While previous studies suggested that the Sunrise field was likely well connected, there still existed a downside risk of compartmentalisation because of the high degree of faulting.
New results from a multi-disciplinary investigation indicate that the Sunrise field is unusually well connected, both vertically and laterally across large distances of possibly up to 40 km. This is primarily because of the nature of the main reservoir, which is thought to be a laterally extensive shoreface facies, and the presence of conductive fault/fracture zones associated with fault reactivation in an active tectonic setting. The results of this study render unlikely the downside case of a highly compartmentalised field. Despite the relatively wide appraisal well spacing, there is confidence in these conclusions because of the consistent message obtained from the evaluation of a wide range of data.
The combination of geochemistry and the modelling of convective mixing through geological time—a method rarely used in the past—give important insights not typically available from traditional methods. This work was also used to successfully guide further data collection, which has supported the initial conclusions regarding the degree of communication across the field.
Liquid loading in wellbores and its effect on cleanup period and well productivity in tight gas sand reservoirs
Authors: Bahrami Hassan , Rezaee M Reza , Rasouli Vamegh , Hosseinian Armin
Published: August 2017

Tight gas reservoirs normally have production problems due to very low matrix permeability and significant damage during well drilling, completion, stimulation and production. Therefore they might not flow gas to surface at optimum rates without advanced production improvement techniques.
After well stimulation and fracturing operations, invaded liquids such as filtrate will flow from the reservoir into the wellbore, as gas is produced during well cleanup. In addition, there might be production of condensate with gas. The produced liquids when loaded and re-circulated downhole in wellbores, can significantly reduce the gas production rate and well productivity in tight gas formations.
This paper presents assessments of tight gas reservoir productivity issues related to liquid loading in wellbores using numerical simulation of multiphase flow in deviated and horizontal wells. A field example of production logging in a horizontal well is used to verify reliability of the numerical simulation model outputs. Well production performance modelling is also performed to quantitatively evaluate water loading in a typical tight gas well, and test the water unloading techniques that can improve the well productivity.
The results indicate the effect of downhole liquid loading on well productivity in tight gas reservoirs. It also shows how well cleanup is sped up with the improved well productivity when downhole circulating liquids are lifted using the proposed methods.
Simulation of hydraulic fracturing in tight formations
Authors: Sarmadivaleh Mohammad , Rasouli Vamegh
Published: August 2017

Production from tight formations is becoming a main focus around the world and particularly in Australia. Hydraulic fracturing is one of the commonly used approaches to stimulate production from tight reservoirs. A good understanding of mechanical properties of formation and the in-situ stresses is essential for a hydraulic fracturing study.
In this work, using the log based approach, the mechanical properties and in-situ stresses were estimated in a tight gas formation. This data is then used as input for 2D numerical simulation of hydraulic fracturing in particle flow code (PFC). The initiation and propagation of an induced fracture was studied by increasing the rock strength to simulate a tight formation response. Thereafter, the model was divided into two zones to investigate the fracture containment capacity to simulate a fracture intersecting an interbed with formation properties being different on the two sides. The formation bond strength was increased on one side of the interbed and fracture extension was monitored. The results of both simulations showed how, by increasing formation strength equivalent to a tighter formation, the fracture extension ability reduces and the interbed containment capacity increases. The results were compared with some of the analytical models and good agreement was observed.
New method for transport and installation of heavy suction anchors and/or structures in extreme deep waters ≥ 2,000 m
Authors: Meijer Sjoerd , Vermeulen Kees Jan , Krabbendam Richard
Published: August 2017

This paper gives an insight in the evolution of deep water lifting capabilities on the J-class installation vessels of Jumbo. Two existing methods that are used for recently executed deepwater installation projects are described together with the pros and cons of each system. Based on this comparison, a new concept for installation of heavy structures in ultra deep water is introduced. An in-house analysis campaign has been executed to check the feasibility of this new concept. The first results and discussion of these results are presented at the end of this paper.
Innovative EM MWD technology facilitates exploitation of unconventional reservoirs
Authors: Coghill Jim , Lee Jonathan , Miller Graham , Zhe Ma , Qinglong Liu , Sosrohadisewoyo Rosano
Published: August 2017

Electromagnetic wave measurement while drilling (EM MWD) systems have historically seen less widespread use compared to mud pulse telemetry due to inherent limits—notably depth and formation characteristics and the limited capability for offshore applications. However, the rapid growth of unconventional applications, such as shale gas reservoir development, underbalanced drilling (UBD) and coalbed methane drilling (CBM) has resulted in an increased need for EM MWD systems.
EM MWD systems have the advantage of no moving parts, which result in the potential for improved reliability compared to mud pulse telemetry systems. In addition, such systems are independent of the rig circulating system, with less time required to make connections, leading to better hole cleaning. It is also possible to drill ahead immediately after the connection is made without losing information from downhole, as no circulating media is required to transmit the data.
Despite these advantages the use of EM MWD has limitations. System performance is limited to depth, specifically true vertical depth (TVD). Signal reception at the surface depends upon the characteristics of the various formations through which the signal is transmitted from downhole, notably formation resistivity.
The authors describe an EM MWD system incorporating a number of features that overcome challenges normally associated with such systems, including variable transmission formats to adapt to a well’s specific conditions, a flexible surface antenna array to optimise signal detection and methods of reducing downhole shock and vibration. Along with a description of the system, case studies from differing geographical locations will demonstrate its effectiveness.
Price reopeners—challenges and opportunities
Authors: Griffin Paul , Smith Herbert
Published: August 2017

The long-term sale and purchase agreements which have long under-pinned the LNG business have seen increasing sophistication in their price review provisions and price re-openers in recent years. But, for all the contractual ingenuity and foresight of these provisions at the time these agreements are entered into, the emergence of connected geographical markets and the increasing volatility of price and volume risk have meant that these provisions are now regularly applied and a number of these provisions found wanting when submitted to practical application.
Among the factors that have contributed to these difficulties are recent changes in the commercial and political aims of a number of the important producer economies and the rapid change in the circumstances of a number of the economies of those states and regions that are consumers of LNG.
This paper contemplates the ways in which today’s circumstances are putting increased stress on these traditional provisions and looks particularly at the challenges of developing effective strategies to mitigate risks and enhance opportunities while maintaining relationships during periods of disagreement.
It also includes case studies that highlight some of the issues of triggering price re-openers and then managing their progress through the resulting re-negotiations or, increasingly, arbitrations and expert determinations.
These case studies include reviews of published decisions on price re-openers and analyses of some of the more usual contractual provisions found in the price and price clauses revision of long-term LNG sale and purchase agreements.
Beneficial use of associated water in the Queensland coal seam gas industry
Authors: Purtill Cristian
Published: August 2017

The Queensland Government has developed an associated water management policy that, among other things, strives to maximise the beneficial use of associated water derived from Queensland’s burgeoning coal seam gas industry.
The Department of Infrastructure and Planning reports that domestic gas production alone (i.e. without an export LNG market) will produce on average 25 GL per annum in the next 25 years. Most of this water has sufficiently high total dissolved solids and other water quality issues to require some form of treatment prior to use. Clearly, the relatively large volumes of water present both challenges and opportunities to the communities in which the CSG industry is developing.
In line with the philosophy of beneficial use of associated water, Santos has developed a portfolio of options within its associated water management strategy and plans for its Arcadia Valley, Fairview and Roma tenements.
The strategy seeks to:

provide enduring value for the community;
maximise benefits while minimising the environmental footprint;
provide a range of alternatives to avoid single-mode failure;
use scalable options in response to uncertainty;
deploy demonstrated technologies; and,
meet and exceed all regulatory requirements.

This paper will set some context around the broader CSG industry’s associated water challenges, and identify what parameters must be considered in arriving at beneficial uses for the water. The paper then explores some of Santos’ approaches to associated water management.
An overview of contemporary project delivery methods for major gas infrastructure
Authors: Callaghan Stephen
Published: August 2017

Recent developments in both relationship contracting and non-traditional project delivery methods have had a substantial impact upon the way organisations within the Australian construction industry carry out their business to achieve successful project delivery.
In the late 1980s, following a period of high-profile disputes, there was a trend towards a more co-operative and collaborative approach to contracting. It was during this time that the concept of partnering was introduced to Australia. Partnering in turn led to the development of relationship contracting.
Relationship contracting has developed into a wide ranging concept which varies from informal agreements to work co-operatively for the success of the project, to the implementation of a pure alliance arrangement and, most recently, the use of ECI.
The concept of relationship contracting brings with it a range of principles and concepts, which include:

shared and common goals;
pro-active objectives and key performance indicators;
issue management and resolution processes;
robust risk and opportunity management;
probity and accountability;
ongoing review and evaluation leading to continuous improvement and team building;
plans and strategies for achieving stretched goals and outstanding performance; and,
pain/gain or incentivised remuneration based on outcomes and performance.
The need for relationship contracting in Australia has increased in recent years due to the substantial growth in construction activity, including a significant increase in the growth of gas sector work. Much of the construction activity has been carried out using a fast track approach in an environment where resources are limited.
This presentation will discuss the development of relationship contracting and, in particular, will look at ECI arrangements and alliance delivery models for gas infrastructure delivery.