bluuebunny/crossref_metadata_2025 huggingface dataset:
Evolution of a protolunar disk in vapor/melt equilibrium
Authors: Ward William R.
Published: January 2017

A model of the viscous evolution of a two‐phase, vapor/melt protolunar disk is described. Droplets condense from the vapor and “rain out,” forming a stratified structure with a midplane magma layer surrounded by a vapor reservoir. The magma layer is gravitationally unstable, but material interior to the Roche distance cannot fragment, and instead develops an effective viscosity. However, magma flowing across the Roche limit can fragment and accrete into moonlets, while magma spreading inward is accreted by Earth. As mass leaves the melt layer, it is replenished by vapor condensation, leading to a quasi steady state (QSS). The layer's mass is maintained at ~13% of a lunar mass and replaced every ~ 3.2 years. The vapor atmosphere steadily decreases, and once exhausted, the disk would cool below condensation temperature and spread as a time‐dependent disk until it too is exhausted. The timescale of the QSS is regulated by the disk's ability to radiate all the released latent heat plus viscous dissipation energy to space at the photospheric temperature, i.e., ~2000 K for silicon phase equilibrium. For the protolunar disk, latent heat dominates viscous heating, and the QSS for a ~2 lunar mass disk lasts for ~ 50 years. For comparison, a hypothetical water/steam disk orbiting an ice giant planet in which viscous heating dominates is also modeled. The photospheric temperature is closer to ~373 K, and the replacement time of the water layer is ~136 years. Finally, disks confined by external torques at either the planet‐disk boundary or at its outer edge are also briefly examined.
Nanoscale‐Coordination‐Polymer‐Shelled Manganese Dioxide Composite Nanoparticles: A Multistage Redox/pH/H2O2‐Responsive Cancer Theranostic Nanoplatform
Authors: Liu Jingjing , Chen Qian , Zhu Wenwen , Yi Xuan , Yang Yu , Dong Ziliang , Liu Zhuang
Published: January 2017

Nanoscale coordination polymers (NCPs) self‐assembled from metal ions and organic bridging ligands exhibit many unique features promising for applications in nanomedicine. In this work, manganese dioxide (MnO2) nanoparticles stabilized by bovine serum albumin are encapsulated by NCP‐shells constructed based on high‐Z element hafnium (Hf) ions and c,c,t‐(diamminedichlorodisuccinato)Pt(IV) (DSP), a cisplatin prodrug. After further modification with polyethylene glycol (PEG), the formed BM@NCP(DSP)‐PEG can simultaneously serve as a radio‐sensitizer owing to the strong X‐ray attenuation capability of Hf to enhance radiotherapy, as well as a chemotherapeutic agent resulting from the reduction‐induced release of cisplatin. Meanwhile, the in situ generated oxygen resulting from MnO2‐triggered decomposition of tumor endogenous H2O2 will be greatly helpful for overcoming hypoxia‐associated radio‐resistance. Upon intravenous injection, BM@NCP(DSP)‐PEG shows efficient tumor homing as well as rapid renal excretion, as illustrated by magnetic resonance imaging and confirmed by biodistribution measurement. Notably, an excellent in vivo tumor growth inhibition effect is observed with BM@NCP(DSP)‐PEG nanoparticles after the combined chemoradiotherapy treatment. Therefore, the NCP‐based composite nanoparticles with inherent biodegradability and no appreciable in vivo toxicity may be a unique type of multifunctional nanoplatform responsive to different parameters in the tumor microenvironment, promising for cancer theranostics with great efficacy.
Redox‐Responsive and Drug‐Embedded Silica Nanoparticles with Unique Self‐Destruction Features for Efficient Gene/Drug Codelivery
Authors: Zhang Qing , Shen Chuanan , Zhao Nana , Xu Fu‐Jian
Published: January 2017

The development of advanced gene/drug codelivery carriers with stimuli‐responsive release manner for complementary cancer therapy is desirable. In this study, novel disulfide‐bridged and doxorubicin (DOX)‐embedded degradable silica nanoparticles (DS‐DOX) with unique self‐destruction features are synthesized by a facile one‐pot method. In order to realize codelivery of genes and drugs, the surface of DS‐DOX nanoparticles is readily functionalized with the assembled polycation (CD‐PGEA), comprising one β‐cyclodextrin core and two ethanolamine‐functionalized poly(glycidyl methacrylate) arms, to achieve DS‐DOX‐PGEA. The redox‐responsive self‐destruction behavior of DS‐DOX imparts DS‐DOX‐PGEA with a better ability to release anticancer drug DOX, while the low‐toxic hydroxyl‐rich CD‐PGEA brushes can efficiently deliver genes for cancer treatment. Very interestingly, the degradation process of DS‐DOX starts from the outside, while the destruction of the degradable silica (DS) nanoparticles without DOX begins from the center of the nanoparticles. The embedded DOX inside the DS‐DOX nanoparticles can significantly influence the structures and facilitate the cellular uptake and the subsequent gene transfection. The as‐developed DS‐DOX‐PGEA nanostructure with coordinating biodegradability, stimuli‐responsiveness, and controlled release manner might be desirable gene/drug codelivery carriers for clinical cancer treatment.
Carbon‐Based Functional Materials Derived from Waste for Water Remediation and Energy Storage
Authors: Ma Qinglang , Yu Yifu , Sindoro Melinda , Fane Anthony G. , Wang Rong , Zhang Hua
Published: January 2017

Carbon‐based functional materials hold the key for solving global challenges in the areas of water scarcity and the energy crisis. Although carbon nanotubes (CNTs) and graphene have shown promising results in various fields of application, their high preparation cost and low production yield still dramatically hinder their wide practical applications. Therefore, there is an urgent call for preparing carbon‐based functional materials from low‐cost, abundant, and sustainable sources. Recent innovative strategies have been developed to convert various waste materials into valuable carbon‐based functional materials. These waste‐derived carbon‐based functional materials have shown great potential in many applications, especially as sorbents for water remediation and electrodes for energy storage. Here, the research progress in the preparation of waste‐derived carbon‐based functional materials is summarized, along with their applications in water remediation and energy storage; challenges and future research directions in this emerging research field are also discussed.
Mechanical Alloying of Metal–Organic Frameworks
Authors: Panda Tamas , Horike Satoshi , Hagi Keisuke , Ogiwara Naoki , Kadota Kentaro , Itakura Tomoya , Tsujimoto Masahiko , Kitagawa Susumu
Published: January 2017

The solvent‐free mechanical milling process for two distinct metal–organic framework (MOF) crystals induced the formation of a solid solution, which is not feasible by conventional solution‐based syntheses. X‐ray and STEM‐EDX studies revealed that performing mechanical milling under an Ar atmosphere promotes the high diffusivity of each metal ion in an amorphous solid matrix; the amorphous state turns into the porous crystalline structure by vapor exposure treatment to form a new phase of a MOF solid solution.
Efficient Access to Chiral Trisubstituted Aziridines via Catalytic Enantioselective Aza‐Darzens Reactions
Authors: Trost Barry M. , Saget Tanguy , Hung Chao‐I (Joey)
Published: January 2017

Herein, we report a Zn‐ProPhenol catalyzed aza‐Darzens reaction using chlorinated aromatic ketones as nucleophilic partners for the efficient and enantioselective construction of complex trisubstituted aziridines. The α‐chloro‐β‐aminoketone intermediates featuring a chlorinated tetrasubstituted stereocenter can be isolated in high yields and selectivities for further derivatization. Alternatively, they can be directly transformed to the corresponding aziridines in a one‐pot fashion. Of note, the reaction can be run on gram‐scale with low catalyst loading without impacting its efficiency. Moreover, this methodology was extended to α‐bromoketones which are scarcely used in enantioselective catalysis because of their sensitivity and lack of accessibility.
Catalytic Double Carbon–Boron Bond Formation for the Synthesis of Cyclic Diarylborinic Acids as Versatile Building Blocks for π‐Extended Heteroarenes
Authors: Igarashi Takuya , Tobisu Mamoru , Chatani Naoto
Published: January 2017

The first catalytic synthesis of cyclic diarylborinic acids is developed using a dihydroaminoborane reagent as the boron source. Unlike previously reported methods that use organolithium reagents, this method allows the easy synthesis of cyclic diarylborinic acids bearing a range of functionalities including CN, CO2Et, CONEt2and NMeCO2tBu. Furthermore, these cyclic diarylborinic acids provide rapid access to skeletal diversity, in particular they enable the synthesis of six‐ to nine‐membered π‐extended heteroarenes through simple cross‐coupling reactions, which are important synthetic targets in both advanced materials and pharmaceuticals.
Effect of treated mica on rheological, cure, mechanical, and dielectric properties of ethylene propylene diene monomer (EPDM)/barium titanate (BaTiO3)/mica
Authors: Su Jun , Zhang Jun
Published: January 2017

In this study, mica, treated by three types of coupling agents, isopropyl trioleic titanate (NDZ105), 3‐aminopropyltriethoxysilane (KH550), and vinyltrimethoxysiloxane homopolymer (SG‐Si6490), were utilized to improve the properties of ethylene propylene diene monomer (EPDM)/barium titanate (BaTiO3) composites. It is found that the addition of untreated mica can increase the complex viscosity, while the KH550 modified mica can reduce the complex viscosity. Compared to single usage of coupling agent SG‐Si6490, the hybrid usage of KH550 and SG‐Si6490 can further increase the tensile strength of EPDM/BaTiO3/SG‐Si6490 treated mica (70/20/10) from 9.10 to 11.01 MPa (22% increase). The untreated mica can increase the interfacial polarity and improve the dielectric constant of EPDM/BaTiO3 (70/30) from 7 to 9 at 40 MHz (28% increase). Moreover, the KH550 treated mica can enhance the thermal conductivity of EPDM/BaTiO3 (70/30) from 0.323 W m−1 K−1 to 0.446 W m−1 K−1 (38% increase). In the meantime, the increased crosslink density caused by coupling agents can increase the volume resistivity of EPDM composites. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44833.
P‐Sulfocalix[6]arene as Nanocarrier for Controlled Delivery of Doxorubicin
Authors: Ostos Francisco J. , Lebrón José A. , Moyá Maria L. , López‐López Manuel , Sánchez Antonio , Clavero Amparo , García‐Calderón Clara B. , Rosado Iván V. , López‐Cornejo Pilar
Published: January 2017

Given the high toxicity of the anthracycline antibiotic doxorubicin (DOX), it is relevant to search for nanocarriers that decrease the side effects of the drug and are able to transport it towards a therapeutic target Here, the encapsulation of DOX by p‐sulfocalix[6]arene (calix) has been studied. The interaction of DOX with the macrocycle, as well as with DNA, has been investigated and the equilibrium constant for each binding process estimated. The results showed that the binding constant of DOX to DNA, KDNA, is three orders of magnitude higher than that to calix, Kcalix. The ability of calixarenes to encapsulate DOX molecules, as well as the capability of the DOX molecules included into the inner cavity of the macrocycle to bind with DNA have been examined. Cytotoxicity measurements were done in different cancer and normal cell lines to probe the decrease in the toxicity of the encapsulated DOX. The low toxicity of calixarenes has also been demonstrated for different cell lines.
Drop‐in biofuel production via conventional (lipid/fatty acid) and advanced (biomass) routes. Part I
Authors: Karatzos Sergios , van Dyk J. Susan , McMillan James D. , Saddler Jack
Published: January 2017

Drop‐in biofuels that are ‘functionally identical to petroleum fuels and fully compatible with existing infrastructure’ are needed for sectors such as aviation where biofuels such as bioethanol/biodiesel cannot be used. The technologies used to produce drop‐in biofuels can be grouped into the four categories: oleochemical, thermochemical, biochemical, and hybrid technologies. Commercial volumes of conventional drop‐in biofuels are currently produced through the oleochemical pathway, to make products such as renewable diesel and biojet fuel. However, the cost, sustainability, and availability of the lipid/fatty acid feedstocks are significant challenges that need to be addressed. In the longer‐term, it is likely that commercial growth in drop‐in biofuels will be based on lignocellulosic feedstocks. However, these technologies have been slow to develop and have been hampered by several technoeconomic challenges. For example, the gasification/Fischer‐Tropsch (FT) synthesis route suffers from high capital costs and economies of scale difficulties, while the economical production of high quality syngas remains a significant challenge. Although pyrolysis/hydrothermal liquefaction (HTL) based technologies are promising, the upgrading of pyrolysis oils to higher specification fuels has encountered several technical challenges, such as high catalyst cost and short catalyst lifespan. Biochemical routes to drop‐in fuels have the advantage of producing single molecules with simple chemistry. However, the high value of these molecules in other markets such as renewable chemical precursors and fragrances will limit their use for fuel. In the near‐term, (1–5 years) it is likely that, ‘conventional’ drop‐in biofuels will be produced predominantly via the oleochemical route, due to the relative simplicity and maturity of this pathway. © 2017 Society of Chemical Industry and John Wiley & Sons, Ltd
Establishing a high yielding streptomyces‐based cell‐free protein synthesis system
Authors: Li Jian , Wang He , Kwon Yong‐Chan , Jewett Michael C.
Published: January 2017

Cell‐free protein synthesis (CFPS) has emerged as a powerful platform for applied biotechnology and synthetic biology, with a range of applications in synthesizing proteins, evolving proteins, and prototyping genetic circuits. To expand the current CFPS repertoire, we report here the development and optimization of a Streptomyces‐based CFPS system for the expression of GC‐rich genes. By developing a streamlined crude extract preparation protocol and optimizing reaction conditions, we were able to achieve active enhanced green fluorescent protein (EGFP) yields of greater than 50 μg/mL with batch reactions lasting up to 3 h. By adopting a semi‐continuous reaction format, the EGFP yield could be increased to 282 ± 8 μg/mL and the reaction time was extended to 48 h. Notably, our extract preparation procedures were robust to multiple Streptomyces lividans and Streptomyces coelicolor strains, although expression yields varied. We show that our optimized Streptomyces lividans system provides benefits when compared to an Escherichia coli‐based CFPS system for increasing percent soluble protein expression for four Streptomyces‐originated high GC‐content genes that are involved in biosynthesis of the nonribosomal peptides tambromycin and valinomycin. Looking forward, we believe that our Streptomyces‐based CFPS system will contribute significantly towards efforts to express complex natural product gene clusters (e.g., nonribosomal peptides and polyketides), providing a new avenue for obtaining and studying natural product biosynthesis pathways. Biotechnol. Bioeng. 2017;114: 1343–1353. © 2017 Wiley Periodicals, Inc.
Randomized clinical trial of duct-to-mucosa pancreaticogastrostomy versus handsewn closure after distal pancreatectomy
Authors: Uemura K , Satoi S , Motoi F , Kwon M , Unno M , Murakami Y
Published: January 2017

Background

Postoperative pancreatic fistula (POPF) remains a major cause of morbidity after distal pancreatectomy. The aim of this study was to investigate whether duct-to-mucosa pancreaticogastrostomy of the pancreatic stump decreased clinical POPF formation compared with handsewn closure after distal pancreatectomy.

Methods

This multicentre RCT was performed between April 2012 and June 2014. Patients undergoing distal pancreatectomy were assigned randomly to either duct-to-mucosa pancreaticogastrostomy or handsewn closure. The primary endpoint was the incidence of clinical POPF. Secondary endpoints were rates of other complications and length of hospital stay.

Results

Some 80 patients were randomized, and 73 patients were evaluated in an intention-to-treat analysis: 36 in the pancreaticogastrostomy group and 37 in the handsewn closure group. The duration of operation was significantly longer in the pancreaticogastrostomy group than in the handsewn closure group (mean 268 versus 197 min respectively; P < 0·001). The incidence of clinical POPF did not differ between groups (7 of 36 versus 7 of 37; odds ratio (OR) 1·03, 95 per cent c.i. 0·32 to 3·10; P = 1·000). The rate of intra-abdominal fluid collection was significantly lower in the pancreaticogastrostomy group (6 of 36 versus 21 of 37; OR 0·15, 0·05 to 0·45; P < 0·001). There were no statistically significant differences in the rates of other complications or length of hospital stay.

Conclusion

Duct-to-mucosa pancreaticogastrostomy did not reduce the incidence of clinical POPF compared with handsewn closure of the pancreatic stump after distal pancreatectomy. Registration number UMIN000007426 (http://www.umin.ac.jp).
Determination of meropenem levels in human serum by high‐performance liquid chromatography with ultraviolet detection
Authors: Roth Thomas , Fiedler Stella , Mihai Sidonia , Parsch Hans
Published: January 2017

Meropenem is a β‐lactam broad‐spectrum antibiotic and belongs to the subgroup of carbapenems. It is primarily used in intensive care units for intravenous treatment of severe infections. To avoid bacterial resistance or toxic side effects, the determination of serum meropenem concentration is highly advisable. A simple and fast method for the quantitative determination of meropenem in human serum using high‐performance liquid chromatography with ultraviolet detection (HPLC/UV) was developed and validated. Meropenem was determined by an isocratic HPLC using a tris(hydroxymethyl)aminomethane buffer (pH 8.5; 15% methanol) as a mobile phase and UV detection at 300 nm, with a flow rate of 1.0 mL/min and an analysis time of 10 min. Chromatographic separation was performed on a Kinetex C18 column (5 μm, 150 × 4.6 mm). In order to remove undesired serum components, solid‐phase extraction was used for sample preparation. Since meropenem is not stable in solution, sample and stock solution were stored at −80°C. After preparation, samples were stable at room temperature for at least 6 h. The calibration curve was linear from 3.5 to 200 mg/L with a correlation coefficient r2 of 0.999. The method is accurate with an intra‐ and inter‐assay precision <18.5%.
Ventriloquation and ghostwriting as responses to oppression in therapy
Authors: Simon Gail
Published: January 2017

Background

People coming to therapy as part of their recovery from torture may choose not to speak or write about their experiences, yet the process of seeking asylum requires that they must hand over their life stories for a true–false adjudication with potentially life and death consequences. When people have been silenced and speaking has become dangerous, there are major ethical challenges for the activist practitioner who, along with the person who has experienced torture, sees the importance of stories not only being understood and shared in ways which are factual but which contain truth.

Methods

I share my experiments with writing as a form of inquiry, specifically ghostwriting and ventriloquation.

Findings

These have the effects of (1) moving the therapeutic process into a collaborative inquiry between the client, an asylum seeker, and me as both counsellor and expert witness; (2) letting fictionalised tellings of ‘real life’ reveal the hidden and complex life stories of clients and counsellors and (3) sharing stories which would otherwise remain hidden and risk perpetuating oppressive practices.

Implications for practice

Ghostwriting and ventriloquation offer the practitioner‐researcher ways of speaking from a first‐person position, from ‘within’ experience rather than a distanced ‘about‐ness’ position. In this dialogical writing, I use actual and imagined inner and outer voices to enable the sound of talk and thought to be reflexively and empathically heard and felt by readers. Relational ethics are considered in how to imagine the other and manage ownership of stories without reproducing oppressive practices.
Reduction of radiation exposure during complex interventions for chronic total coronary occlusions: Implementing low dose radiation protocols without affecting procedural success rates
Authors: Werner Gerald S. , Glaser Peggy , Coenen Anja , Moehlis Hiller , Tischer Karl‐Heinz , Koch Matthias , Klingenbeck Reinhold
Published: January 2017

Background

The increasing complexity of percutaneous coronary intervention (PCI) for chronic total coronary occlusions (CTO) leads to a significant increase of radiation exposure for both patient and operator.

Objective

To study the potential of modified settings of the X‐ray equipment combined with operator protocols to reduce radiation dose despite increasing procedural complexity.

Patients and Methods

We analyzed a consecutive cohort of 984 PCIs for CTOs in 863 patients between January 2010 and July 2015. During that period, the X‐ray equipment was changed from an analog to a digital detector system, and a subsequent filter and imaging modification was implemented. The fluoroscopy settings were reduced from 15 pulses/s to 7.5, and then to 6. The cine framerate was reduced from 15 to 7.5/s. For the last time period, with optimized settings, procedural, and lesion related factors influencing the radiation exposure were analyzed.

Results

The lesion complexity increased from a J‐CTO score of 1.64 to 2.33 with an increase of retrograde procedures from 21.6 to 50.4%. With a similar fluoroscopy time, the dose area product was reduced from period 1 to 2 by 20%, and further by 7% to period 3. There was a significant reduction of Air Kerma from period 2 to 3 from 3.5 to 2.7 Gy. The operator exposure was reduced by more than half. The patient's weight and the complexity of the procedure were the main determinants of radiation exposure.

Conclusions

The radiation exposure for patient and operator was decreased considerably during the three observation periods despite an increase in lesion and procedural complexity. Rigorous implementation of radiation device settings did reduce radiation exposure without impeding procedural success. © 2017 Wiley Periodicals, Inc.
The art of vaginal breech birth at term on all fours
Authors: Wildschut Hajo I. J. , van Belzen‐Slappendel Hinke , Jans Suze
Published: January 2017

Key Clinical Message

Despite a shift in clinical practice favouring cesarean section for breech presentation, adequate skills are still needed for a safe vaginal breech birth. This case report illustrates the physiological mechanism of vaginal breech birth. The accompanying pictures are a testimony to the “hands‐off” approach and could be used for educational purposes.
Explicit Radial‐Basis‐Function‐Based Finite‐Difference Method for Interfacial Mass‐Transfer Problems
Authors: Falcone Manuel , Marschall Holger
Published: January 2017

The development of an efficient and accurate numerical method, able to capture the very thin concentration boundary layer in cases of interfacial mass transfer at fluid interfaces in two‐phase systems, is a challenging task. In this study, a mesh‐less finite‐difference method based on radial basis functions has been adopted. The use of radial basis functions has proven to be helpful in multidimensional problems with complex geometries, in which the use of scattered sets of nodes is preferable. Unlike most of the applications reported in literature, the proposed method has been employed in two‐phase flows, with two regions connected by a surface, i.e., the fluid interface, on which additional boundary conditions have to be fulfilled. Two validation test cases with increasing complexity are presented.
Liquid Mixing Time in Dense Solid‐Liquid Stirred Tanks
Authors: Paglianti Alessandro , Carletti Claudio , Montante Giuseppina
Published: January 2017

The liquid mixing time in solid‐liquid systems is difficult to determine by quantitative and non‐intrusive methods, particularly at high solid loadings. Three methods are considered for the post‐processing of raw conductivity data collected by electrical resistance tomography (ERT) in a baffled stirred tank. A novel approach is suggested to overcome the limitations of the section‐averaged conductivity evaluations and the problems associated with the solids disturbances affecting the local conductivity data. The new approach, which is based on the classic post‐processing method devised for the mixing time determination in optically accessible stirred tanks by planar laser‐induced fluorescence, is successfully applied to the ERT data collected either under single‐phase or two‐phase conditions.
Reversible C60 Ejection from a Metallocage through the Redox‐Dependent Binding of a Competitive Guest
Authors: Colomban Cédric , Szalóki György , Allain Magali , Gómez Laura , Goeb Sébastien , Sallé Marc , Costas Miquel , Ribas Xavi
Published: January 2017

The reversible encapsulation of a tetrapyridyl extended‐tetrathiafulvalene (exTTF)‐based ligand (m‐Py)exTTF by a tetragonal Zn‐porphyrin‐based prismatic nanocage (1) is described. The reversible uptake and release of the (m‐Py)exTTF guest proceeds through drastic electronic and conformational changes occurring upon oxidation of the latter. This reversible system has been explored in a guest‐exchange process, by addition of (m‐Py)exTTF to the host–guest complex [C60⊂1], leading to fullerene C60 ejection from the host cavity. Remarkably, the subsequent redox‐triggered ejection of (m‐Py)exTTF, leads to the recovery of the empty cage 1, which remains available for further C60 encapsulation. The C60 ejection is justified by the preferable coordination of the pyridine anchors of (m‐Py)exTTF to the two Zn‐porphyrin units of 1. This approach, based on the use of a switchable competitive guest, offers a promising new strategy for guest‐delivery control.
THE VELOCITY DISPERSION AND ATTENUATION OF MARINE HYDRATE‐BEARING SEDIMENTS
Authors: Ru‐Wei ZHANG , Hong‐Qi LI , Peng‐Fei WEN , Bao‐Jin ZHANG
Published: January 2017

P‐wave and S‐wave velocity will increase and the attenuation will vary when the concentration of gas hydrate increases. The analysis of velocity dispersion and attenuation for hydrate‐bearing sediments (GHBS) would contribute to the estimate of gas hydrate concentration. Based on effective medium theory (EMT), we study the nonlinear variation feature of P‐wave and S‐wave velocity for marine unconsolidated hydrate‐bearing sediments. Moreover, we use BISQ model to replace Gassmann equation in the EMT, and research the velocity dispersion and attenuation of hydrate‐bearing sediments in the full frequency band. Based on this model, the velocity and attenuation always increase with the increasing amount of gas hydrate, and the rock porosity and clay content doesn't make any differences to the attenuation. After the numeral modeling, we apply the sonic logging (20 kHz) and VSP (100 Hz) data from Ocean drilling Program (ODP) leg 164 in obtaining the concentration of gas hydrate stability zone (GHSZ). In the application, the average hydrate concentration of GHSZ from site 995 in ODP leg 164 is about 5%∼7%, and corresponds to the pressure core sample (PCS) data, Helgerud et al.'s research conclusions and the prediction data from neural network (NN). Due to the velocity dispersion, the estimated hydrate concentration from VSP data would be lower than the estimated results from sonic logging data. The prediction results of three hydrate Sites (SH2, SH3 and SH7) from Shenhu area also coincide with the PCS, South China Sea. Moreover, based on the peak frequency method, the effective seismic quality factors (Q) of the BSR are estimated from the inline prestack seismic gathers. The Q‐values suggest that the effective saturation of gas hydrate estimated by this model fluctuates between 15%∼30%. The results of numeral modeling and applications indicate the velocity dispersion and attenuation of GHBS always vary with the concentration of hydrate. The study of velocity dispersion and attenuation feature for GHBS in the full frequency band would contribute to the estimate of gas hydrate concentration.
OPPOSING COILS TRANSIENT ELECTROMAGNETIC METHOD FOR SHALLOW SUBSURFACE DETECTION
Authors: Zhen‐Zhu XI , Xia LONG , Sheng ZHOU , Long HUANG , Gang SONG , Hai‐Tao HOU , Liang WANG
Published: January 2017

Transient electromagnetic method (TEM) is a commonly‐used geophysical method of measuring the secondary electromagnetic field induced by transient pulse sources. Because of the inherent mutual‐induction between TX and RX coils, the measured field always contains the mutual‐induction field, which becomes stronger when TX coil becomes smaller and closer to RX coil. It influences the near‐surface TEM systems, which utilize small TX coils to effectively resolve the near surface explorations. The mixture of the mutual‐induction field with the secondary field at early period leads to a blind region in the shallow surface in TEM exploration. To solve this problem, we applied two concentric and parallel current coils in the TEM system. They are opposing coils, which means that the two coils are physically same, but the currents in them are of equal value and in reverse directions. The RX coil is equidistant to the two opposing coils. By means of this special arrangement, the mutual‐induction field received at the RX coil is zero, which means that the mutual induction effect is efficiently eliminated, and pure secondary field of the conductive underground will be measured. It is proved by theory and model calculation that opposing coils transient electromagnetic method has advantages in lateral resolution. It is quite suitable for small coil TEM system aiming at shallow subsurface detection.
GEOPHYSICAL ANALYSIS OF ABNORMAL SEISMIC (OCEANOGRAPHY) REFLECTION CHARACTERISTICS OF OCEANIC BOTTOM BOUNDARY LAYER
Authors: Jiang‐Xin CHEN , Yang BAI , Yong‐Xian GUAN , Sheng‐Xiong YANG , Hai‐Bin SONG , Bo‐Ran LIU
Published: January 2017

Traditional seismic oceanography researches dominantly pay attention to the oceanographic phenomena within the water column, such as internal wave, eddy, thermohaline fine structure, water mass boundaries, internal tide, thermohaline staircase, lee wave and so on, and could provide extra information quantitatively and qualitatively as compared with physical oceanography method. So far, very few researches try to study the water column near the seafloor, which is a significant boundary layer where water‐sediment dynamic interaction, cold seepage, hydrothermal vents, biochemical activities and energy dissipation of many oceanic processes may occur. To be different from previous seismic oceanography researches, this paper mainly focuses on seismic reflections of seawater columns near the seafloor, by reprocessing a large amount of seismic sections acquired in the west and north of the South China Sea.

In this paper, conventional seismic facies analysis method is used to analyze, classify and summarize the external geometry, internal configuration, continuity, amplitude and apparent frequency of some complex seismic reflections of seawater column near the seafloor. Combined with the past research results of seismic oceanography, theory of bottom boundary layer and other various processes near the seafloor, this article not only classifies the reflection characteristics of meso‐scale eddies, internal solitary wave and Lee wave, but also speculates that some possible processes could result in a few of the newly discovered abnormal seismic reflections. For example, sheet seismic facies unit may reflect turbulent bottom boundary layer; hair‐like reflection configuration can be caused by the sediment resuspension, resulted from the interaction of bottom current and high frequency undulating seafloor, such as sand dunes; plume seismic facies unit indicates the characteristic of seep plume; and broom seismic facies unit could be associated with the upwelling currents and sediment resuspension in pockmarks. Results indicate that seismic oceanography can image not only processes of the ocean water column, such as internal wave and eddy, but also some complex processes near the seafloor, which greatly expands the research field of seismic oceanography and provides a new method and research perspective for the field observation of processes near the seafloor. Here, bottom boundary layer refers to the water column near the seafloor, and we call all the processes of this region “seafloor processes”.
CHARACTERISTICS OF SEISMICITY OF THE XIAOWAN RESERVOIR IN AN AREA OF ACTIVE TECTONICS FROM DOUBLE‐DIFFERENCE RELOCATION ANALYSIS
Authors: Jin‐Zhong JIANG , Hong FU , Qi‐Fu CHEN
Published: January 2017

We simultaneously relocate the M ≥ 1.0 earthquakes occurred from July 2005 to December 2014 in Xiaowan reservoir area, which is located in an active tectonic region in the middle and lower section of Lancang Jiang in western Yunnan province of China, using cross‐correlation (CC) and double‐difference (DD) method. The relocated epicenters are distinctly clustered in 8 subareas (subarea A to H), and the earthquakes located inside the Xiaowan reservoir area are generally shallower than that outside of the reservoir area. The relocated focal depths, the relation between the seismicity and water level, and the calculated b values in different subareas indicate that the characteristics of seismicity within Xiaowan reservoir area are quite complicated. The earthquakes occurred outside of the reservoir areas are likely to be tectonic earthquakes irrelevant to water filling of Xiaowan reservoir, and there are both reservoir‐triggered seismicity (RTS) and tectonic earthquake activities in Xiaowan reservoir area. The reservoir‐triggered earthquakes (RTE) are mainly located along the Heihui Jiang (subarea A) and Lancang Jiang (subarea B and C), and could be classified into rapid response RTS. In subarea A, a significant “migration” of hypocenters is observed in the first filling cycle along the Heihui valley and Qiaoxi‐Weihou fault zone, which probably indicates the water permeation process in this area. According to the distribution of active faults, rock properties and relocated focal depths in the reservoir area, we suggest that the karst action and fluid permeation caused by water filling, and fault movements are the key factors of RTS in Xiaowan reservoir. Further studies are needed to better understand the physical process of RTS and tectonic seismicity in some subareas in the reservoir.
Racial disparities in cervical cancer: Worse than we thought
Authors: Dalton Heather J. , Farley John H.
Published: January 2017

Racial disparities in cervical cancer mortality continue to be a problem in the United States. Access to adequate cervical cancer screening and preventative care remains critical to eliminating racial disparities. See also pages 1044‐50.
Three‐dimensional assessment of impingement risk in geometrically parameterised hips compared with clinical measures
Authors: Cooper Robert J. , Mengoni Marlène , Groves Dawn , Williams Sophie , Bankes Marcus J.K. , Robinson Philip , Jones Alison C.
Published: January 2017

Abnormal bony morphology is a factor implicated in hip joint soft tissue damage and an increased lifetime risk of osteoarthritis. Standard 2‐dimensional radiographic measurements for diagnosis of hip deformities, such as cam deformities on the femoral neck, do not capture the full joint geometry and are not indicative of symptomatic damage.

In this study, a 3‐dimensional geometric parameterisation system was developed to capture key variations in the femur and acetabulum of subjects with clinically diagnosed cam deformity. The parameterisation was performed for computed tomography scans of 20 patients (10 female and 10 male). Novel quantitative measures of cam deformity were taken and used to assess differences in morphological deformities between males and females.

The parametric surfaces matched the more detailed, segmented hip bone geometry with low fitting error. The quantitative severity measures captured both the size and the position of cams and distinguished between cam and control femurs. The precision of the measures was sufficient to identify differences between subjects that could not be seen with the sole use of 2‐dimensional imaging. In particular, cams were found to be more superiorly located in males than in females.

As well as providing a means to distinguish between subjects more clearly, the new geometric hip parameterisation facilitates the flexible and rapid generation of a range of realistic hip geometries including cams. When combined with material property models, these stratified cam shapes can be used for further assessment of the effect of the geometric variation under impingement conditions.
Acid Inhibitory Effect of a Combination of Omeprazole and Sodium Bicarbonate (CDFR0209) Compared With Delayed‐Release Omeprazole 40 mg Alone in Healthy Adult Male Subjects
Authors: Kim Kyu‐Nam , Yang Sung‐Won , Kim Hyunil , Kwak Seong Shin , Kim Young‐Sang , Cho Doo‐Yeoun
Published: January 2017

CDFR0209, a combination of an immediate‐release formulation of omeprazole 40 mg and sodium bicarbonate 1100 mg, has been developed to treat acid‐related disorders. We compared the acid inhibitory effects of CDFR0209 and delayed‐release omeprazole (omeprazole‐DR, Losec 40 mg) after repeated dosing in Helicobacter pylori–negative healthy adult male subjects. In this 2‐period crossover study, 30 subjects were randomized to CDFR0209 or omeprazole‐DR daily for 7 days. An ambulatory continuous 24‐hour intragastric pH recording was performed at baseline and on days 1 and 7 of each administration period. Integrated gastric acidity was calculated from time‐weighted average hydrogen ion concentrations at each hour of the 24‐hour record. An analysis of variance model was used to test the pharmacodynamic equivalence of CDFR0209 and omeprazole‐DR, using the natural logarithmic transformation of the percent decrease from baseline in integrated gastric acidity for the 24‐hour interval after the seventh dose of each omeprazole formulation. The geometric least‐squares mean ratios (CDFR0209/omeprazole‐DR) of the percent decrease from baseline in integrated gastric acidity was 0.98 (90%CI, 0.93–1.07). Both CDFR0209 and omeprazole‐DR are equally effective in decreasing integrated gastric acidity at steady state.
Rationalising Heteronuclear Decoupling in Refocussing Applications of Solid‐State NMR Spectroscopy
Authors: Frantsuzov Ilya , Vasa Suresh K. , Ernst Matthias , Brown Steven P. , Zorin Vadim , Kentgens Arno P. M. , Hodgkinson Paul
Published: January 2017

Factors affecting the performance of 1H heteronuclear decoupling sequences for magic‐angle spinning (MAS) NMR spectroscopy of organic solids are explored, as observed by time constants for the decay of nuclear magnetisation under a spin‐echo (
). By using a common protocol over a wide range of experimental conditions, including very high magnetic fields and very high radio‐frequency (RF) nutation rates, decoupling performance is observed to degrade consistently with increasing magnetic field. Inhomogeneity of the RF field is found to have a significant impact on
values, with differences of about 20 % observed between probes with different coil geometries. Increasing RF nutation rates dramatically improve robustness with respect to RF offset, but the performance of phase‐modulated sequences degrades at the very high nutation rates achievable in microcoils as a result of RF transients. The insights gained provide better understanding of the factors limiting decoupling performance under different conditions, and the high values of
observed (which generally exceed previous literature values) provide reference points for experiments involving spin magnetisation refocussing, such as 2D correlation spectra and measuring small spin couplings.
Roles of the seasonal dynamics of ecosystem components in fluctuating indirect interactions on a rocky shore
Authors: Wada Yoko , Iwasaki Keiji , Ida Takashi Y. , Yusa Yoichi
Published: January 2017

Accurately evaluating the strengths of direct (i.e., consumptive and non‐consumptive) effects and indirect (density‐ and trait‐mediated) interactions is crucial for understanding the mechanisms of the maintenance and dynamics of an ecosystem. However, an in situ evaluation has not been conducted for a long enough period of time to fully consider the seasonality and life histories of the community components. We conducted a 9‐month (from summer to spring) field experiment in an intertidal rocky shore ecosystem involving the carnivorous snail, Thais clavigera, its prey, the limpet Siphonaria sirius, and their resources, the cyanobacterium (blue‐green alga) Lithoderma sp. and the green algae Ulva spp. From summer to autumn, the predation pressure was high, and the consumptive and non‐consumptive effects of the predator had opposite (positive and negative, respectively) effects on the prey. Both the density‐ and trait‐mediated indirect interactions decreased the coverage of Lithoderma and increased the coverage of Ulva. As the predation pressure decreased in autumn, the predator affected both the adults and the new recruits of the prey. The trait‐mediated interactions still existed, but the density‐mediated interactions were not detected. From winter to spring, no direct effects or indirect interactions were detected because of the low predation pressure. Our investigation highlights previously unnoticed processes—showing that the strengths of the direct effects and indirect interactions fluctuate greatly with the seasonality of the ecosystem components.
Which product characteristics are preferred by Chinese consumers when choosing pork? A conjoint analysis on perceived quality of selected pork attributes
Authors: Ma Xiu Q. , Verkuil Julia M. , Reinbach Helene C. , Meinert Lene
Published: January 2017

Due to the economic growth achieved by China over the past 20 years, Chinese consumers have changed their purchasing behavior regarding meat. Instead of buying locally produced pork, they are increasingly willing to purchase imported pork. A conjoint analysis investigated how intrinsic pork attributes (fat content and processing) and extrinsic pork attributes (origin, price, and packaging) relate to the perceived quality of pork and the choices made by Chinese consumers. A questionnaire distributed among a sample of Chinese consumers (n = 81) revealed that processing (fresh/frozen) is the most important determinant of pork choice (36%), followed by fat content (27%), origin (18%), price (12%), and packaging (6.6%). Estimates of utility showed that Chinese consumers value fresh pork highly (0.147), followed by lean pork (0.111) and pork imported from countries other than China (0.073). The findings indicate that Chinese consumer's value both intrinsic and extrinsic attributes, and these results may help the meat industry improve China's competitive meat market by developing new and more products that are tailored to the needs of the consumer.
Tracing the Alkinoos Harbor of ancient Kerkyra, Greece, and reconstructing its paleotsunami history
Authors: Finkler Claudia , Fischer Peter , Baika Kalliopi , Rigakou Diamanto , Metallinou Garyfalia , Hadler Hanna , Vött Andreas
Published: January 2017

In this study, the Alkinoos Harbor of ancient Corfu was investigated by means of geomorphological and sedimentological methods in order to reconstruct the ancient harbor's construction, its period of use and spatial extent, and local paleoenvironmental changes. We present sedimentological evidence for the Alkinoos Harbor that shows distinct signs of dredging activities. Although the harbor must have been in use from the Archaic period onwards, a set of paleoenvironmental proxies based on vibracoring, geophysical prospection, electrical conductivity logging, microfaunal studies, and geochemical analyses revealed typical sediments of a closed, protected Roman harbor that was in use between the 1st and 6th century A.D. In addition, sedimentological and microfaunal evidence allowed us to differentiate between different parts of the Roman harbor. In contrast, the pre‐Roman harbor and its shipsheds were built on a sandy seashore. Our data revealed two distinct stratigraphic disruptions related to tsunamigenic impact. These paleotsunamis were dated between the 3rd and 6th century A.D. and between the 5th and 6th century A.D., most probably correlating with the A.D. 365 (Crete) and 6th century A.D. (Peloponnese) supraregional events, respectively. The Alkinoos Harbor turned out to be an outstanding geoarchive to reconstruct human‐environment interactions during the late Holocene.
Reworked volcaniclastic deposits from the Usumacinta river, Mexico: A serendipitous source of volcanic glass in Maya ceramics
Authors: Cabadas‐Báez Héctor Víctor , Solís‐Castillo Berenice , Solleiro‐Rebolledo Elizabeth , Sedov Sergey , Leonard Daniel , Teranishi‐Castillo Keiko , Liendo‐Stuardo Rodrigo , Korneychik Oleg
Published: January 2017

The origin and distribution of volcanic glass temper in Maya ceramics has attracted the attention of Mesoamerican archaeologists for the last 80 years. Several Quaternary volcanoes, particularly those in the Central American Volcanic Arc (CAVA), are proposed as the source of tephra in the Maya region, however, a continuous stratigraphic record of this tephra deposit is still lacking. A reworked volcaniclastic deposit (9 ± 2 ka) was located in the Usumacinta River fluvial sequence from Tabasco State, Mexico. This material has been found in ceramics from the Tierra Blanca archaeological site, which developed from the Formative to Late Classic Maya period. Cross‐bedding sedimentary structures and amygdaloidal texture in pumice indicate the influence of the fluvial environment and the weathering exposition of the volcanic deposit. The comparative geochemical and petrographic features provide the first evidence that this volcanic ash “outcrop” was used for local ceramic manufacture. The volcanic event that produced the tephra is difficult to identify due to the dynamic sedimentary environment that obliterated and mixed the original mineralogy and geochemistry. Eruptions with rhyolitic magma are the most probable candidates. This assumption contradicts the widespread hypothesis that the tephra of El Chichón volcano is the source of volcanic glass in Classic Maya ceramics.