bluuebunny/crossref_metadata_2025 huggingface dataset:
Quantification of flow volume with a new digital three‐dimensional color Doppler flow approach: an in vitro study.
Authors: Li J , Li X , Mori Y , Rusk R A , Lee J S , Davies C H , Hashimoto I , El-Sedfy G O , Li X N , Sahn D J
Published: January 2017

The quantification of flow stroke volume is important for evaluation of patients with cardiac dysfunction and cardiovascular disease. Three‐dimensional digital color Doppler flow imaging allows the acquisition of flow data in an orientation approximately parallel to flow and analysis of the Doppler flow velocities perpendicular to flow (cross‐sectional flow calculation). This in vitro study assessed the applicability of this method for quantifying cardiac output in a funnel‐shaped tube model similar to mitral inflow or the left ventricular outflow tract.

A new digital three‐dimensional color Doppler method was used to acquire Doppler flow information. Raw scan line data with digital velocity assignments were obtained on a conventional Doppler color flow imaging system with a 180 degrees rotating multiplanar transesophageal probe connected to a computer workstation. Nine stroke volumes (20‐60 mL) with flow rates ranging from 1.5 to 5.28 L/min in a funnel‐shaped pulsatile laminar flow model were studied. Three‐dimensional flow rates were compared with standard‐of‐reference measurements of flow obtained from timed collection in a graduated cylinder and with an ultrasonic flow meter.

Within the funnel tube, the flow volumes that were calculated from the first, second, and third depths and the average of all 3 depths correlated well with the actual flow rate (r = 0.97‐0.99). Results from the middle and second levels and from the average of all 3 depths provided the closest fit to the actual flow rates (r = 0.99; y = 0.96x + 0.14; and r = 0.98; y = 1.14x ‐ 0.43, respectively).

Although a work in progress, this digital three‐dimensional color Doppler flow measurement method is feasible, accurate, and simple, and it may offer in vivo evaluation of blood volume flow given a favorable orientation between the valve orifice and the scanning device.
Quantitative Ultrasound Measurement of the Calcaneus in Southeast Asian Children With Thalassemia
Authors: Sani Fadhli Mohamed , Sarji Sazilah Ahmad , Bilgen Mehmet
Published: January 2017

Objectives

The purpose of this study was to test the hypothesis that quantitative ultrasound properties of the calcaneus in Southeast Asian children treated for thalassemia have different characteristics than those of their healthy counterparts and thereby can be used for assessing the risk of osteoporosis.

Methods

Broadband ultrasound attenuation and the speed of sound were measured from groups of thalassemic and healthy children and compared with bone mineral density (BMD) estimated from dual‐energy X‐ray absorptiometry to determine intergroup and intragroup dependencies of the measurements and variations with differences in sex and anthropometric characteristics.

Results

Broadband ultrasound attenuation and speed of sound measurements were found to be independent of sex but dependent on age in the thalassemic children. Consistently, broadband ultrasound attenuation had lower values and the speed of sound had higher values compared with those of the healthy children in each age group. Broadband ultrasound attenuation correlated well with the speed of sound and also with age, weight, and height, but the speed of sound did not show an association with these parameters. Broadband ultrasound attenuation correlated moderately with BMD in the lumbar spine and whole body, but the corresponding association was much weaker for the speed of sound. In the thalassemic children, both broadband ultrasound attenuation and BMD increased with age as they grew older but not fast enough compared with the healthy children, and the risk of osteoporosis was greater at older ages.

Conclusions

Calcaneal quantitative ultrasound may be used as a diagnostic screening tool for assessing the bone status in thalassemic Southeast Asian children and for deciding whether further dual‐energy X‐ray absorptiometry is needed, particularly in those who are at a greater risk for osteoporosis as identified by low body weight and height.
Comparison of soil wetness from multiple models over Australia with observations
Authors: Vinodkumar  , Dharssi I. , Bally J. , Steinle P. , McJannet D. , Walker J.
Published: January 2017

The McArthur Forest Fire Danger Index used in Australia for operational fire warnings has a component representing fuel availability called the Drought Factor (DF). The DF is partly based on soil moisture deficit, calculated as either the Keetch‐Byram Drought Index (KBDI) or Mount's Soil Dryness Index (MSDI). The KBDI and MSDI are simplified water balance models driven by observation based daily rainfall and temperature. In this work, gridded KBDI and MSDI analyses are computed at a horizontal resolution of 5 km and are verified against in‐situ soil moisture observations. Also verified is another simple model called the Antecedent Precipitation Index (API). Soil moisture analyses from the Australian Community Climate and Earth System Simulator (ACCESS) global Numerical Weather Prediction (NWP) system as well as remotely sensed soil wetness retrievals from the Advanced Scatterometer (ASCAT) are also verified. The verification shows that the NWP soil wetness analyses have greater skill and smaller biases than the KBDI, MSDI and API analyses. This is despite the NWP system having a coarse horizontal resolution and not using observed precipitation. The average temporal correlations (root mean square difference) between cosmic ray soil moisture monitoring facility observations and modeled or remotely sensed soil wetness are 0.82 (0.15 ±0.02), 0.66 (0.33 ±0.07), 0.77 (0.20 ±0.03), 0.74 (0.22 ±0.03) and 0.83 (0.18 ±0.04) for NWP, KBDI, MSDI, API and ASCAT. The results from this study suggests that analyses of soil moisture can be greatly improved by using physically based land surface models, remote sensing measurements and data assimilation.
Labyrinths in large reservoirs: An invisible barrier to fish migration and the solution through reservoir operation
Authors: Xu Zhihao , Yin Xinan , Sun Tao , Cai Yanpeng , Ding Yu , Yang Wei , Yang Zhifeng
Published: January 2017

Reservoir construction changes a river's natural flows and temperature, thereby threatening fish migration. Researchers have tried to restore fish migration passages by ensuring environmental flows in downstream river channels. However, reservoir impoundment changes upstream environments from lotic to lentic and thereby hinders fish migration by eliminating migration cues, which has been rarely considered. This study characterized the invisible barriers that large reservoirs create for migratory fish. Water currents are the primary orientation cues for migration due to fish's natural rheotactic tendency. Fish also require suitable temperatures during migration. We built a quasi‐3‐D model to simulate hydrodynamic and temperature conditions in large reservoirs and tested whether these conditions met the velocity and temperature requirements of fish. Due to the strong effects of operation on reservoir conditions, we proposed an eco‐friendly technical operating solution to restore migration passages. We added an ecological constraint (i.e., creating a suitable velocity field for fish migration) to reservoir operation model and applied multiobjective optimization to simultaneously protect reservoir benefits. As a case, we applied our approach to China's Danjiangkou Reservoir. We found that velocities in more than half of the zones along the potential fish migration route through the reservoir were lower than the fish requirement and could not offer orientation cues for migration. The eco‐friendly operating scheme effectively restored a fish migration passage by managing reservoir releases during key migration periods, slightly reducing the reservoir's socioeconomic benefits by 1.67–5.03%. This study provides a new perspective on biodiversity and fisheries protection in global regulated rivers.
Senescence is delayed when ramie (Boehmeria nivea L.) is transformed with the isopentyl transferase (ipt) gene under control of the SAG12 promoter
Authors: An Xia , Zhang Jingyu , Liao Yiwen , Liu Lijun , Peng Dingxiang , Wang Bo
Published: January 2017

Ramie is an economically important industrial fiber crop widely planted in China, India, and other Southeast Asian and Pacific Rim countries. It plays an important role in China's economy, where ramie farming, industry, and trade provide livelihood support to about five million people. However, poor fiber production resulting from leaf senescence and leaf abscission is a significant problem. In this study, we report the successful production of transgenic ramie plants which delayed leaf senescence and enhanced biomass. Transgenic ramie plants were obtained via transformation with the Agrobacterium tumefaciens strain harboring the binary vector pSG529 containing the isopentyl transferase (ipt) gene under control of the SAG12 promoter (PSAG12‐ipt construct). Agrobacterium tumefaciens strain EHA105 was used for the midrib explant transformation. The transformation frequency was 28.29%. Southern blot confirmed the integration of 1–4 copies of the NPTII gene into the ramie genome in the tested lines. At the fiber maturation stage, the transgenic plants had higher photosynthesis rates, chlorophyll content (SPAD values), and stronger resistance to exogenous ethylene compared with wild‐type plants.
Direct Oxidative Cross‐Coupling of Toluene Derivatives and N‐Acyl‐2‐aminoacetophenones
Authors: Yu Hui , Xu Yilan , Dong Rui , Fang Yan
Published: January 2017

The direct oxidative cross‐coupling between N‐acyl‐2‐aminoacetophenones and toluene derivatives was developed with a new C–C bond being formed under metal‐free and environmentally friendly conditions with excellent atom economy. A possible reaction pathway for the formation of the products is also discussed in this paper.

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Ruthenium Complexes Immobilized on Functionalized Knitted Hypercrosslinked Polymers as Efficient and Recyclable Catalysts for Organic Transformations
Authors: Jia Zhifang , Wang Kewei , Tan Bien , Gu Yanlong
Published: January 2017

A hypercrosslinked polymer (HCP)‐immobilized ruthenium catalyst (HCP–PPh3–Ru) was prepared from benzene and triphenylphosphine (PPh3) through a one‐step external cross‐linking reaction. The structure and composition of the catalyst were fully characterized by many physicochemical methods. HCP–PPh3–Ru was found to possess high Brunauer–Emmett–Teller (BET) surface area, large pore volume, and low skeletal density. Moreover, the Ru catalyst was also featured some advantages, such as low synthetic cost and good chemical and thermal stability. HCP–PPh3–Ru was then used as a recoverable and effective catalyst for the synthesis of 2,4‐diaryl‐substituted pyridines from acetophenones, ammonium acetate (NH4OAc) and dimethylformamide (DMF), and the cycloaddition reaction of diazodicarbonyl compounds with olefins to afford dihydrofurans. In addition, a combination of HCP–PPh3–Ru and Amberlyst‐15 enabled us to establish a simple protocol for the direct synthesis of carbazole derivatives from diazodicarbonyl compound, alkyl vinyl ether and indole. In these selected reactions, the catalyst was easily recovered and reused several times without significant activity loss.

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Planar Chiral Cyclic (Amino)(ferrocenyl)carbene as Ligand for Transition Metals
Authors: Yasue Risa , Miyauchi Masaru , Yoshida Kazuhiro
Published: January 2017

Planar chiral ferrocene‐fused iminium salts were synthesized in enantiomerically pure form. The novel planar chiral cyclic (amino)(ferrocenyl)carbene successfully generated from such salt was subjected to carbene trapping experiments with sulfur and copper chloride. The utility of the carbene as a chiral ligand for transition metals was preliminarily demonstrated in the copper‐catalyzed enantioselective β‐boration of an α,β‐unsaturated ester.

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An Iron(II) Chloride‐Promoted Radical Cascade Methylation or α‐Chloro‐β‐methylation of N‐Arylacrylamides with Dimethyl Sulfoxide
Authors: Li Zejiang , Cui Xiaosong , Niu Lin , Ren Yingming , Bian Menghua , Yang Xuebiao , Yang Biao , Yan Qinqin , Zhao Jincan
Published: January 2017

A free radical‐initiated methylation and/or α‐chloro‐β‐methylation of N‐arylacrylamides with dimethyl sulfoxide under the analogous Fenton reaction condition has been developed, which provides an effective and facile cascade strategy for the synthesis of oxindoles and chlorinated amides.

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Recent Developments in Trifluoromethylation or Difluoroalkylation by Use of Difluorinated Phosphonium Salts
Authors: Zhang Cai
Published: January 2017

Recent advances in trifluoromethylation or difluoroalkylation reactions by use of difluorinated phosphonium salts are summarized. In the presence of base, water, photocatalyst, fluoride or under the heating conditions, the difluorinated phosphonium salts can produce difluorocarbene, the CF2H radical or the trifluoromethyl anion, which are major intermediates for the difluoroalkylation or trifluoromethylation reaction and give moderate to excellent yields of the desired products in most cases.

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Relapse risk and survival in patients with FLT3 mutated acute myeloid leukemia undergoing stem cell transplantation
Authors: Gaballa Sameh , Saliba Rima , Oran Betul , Brammer Jonathan E. , Chen Julianne , Rondon Gabriela , Alousi Amin M. , Kebriaei Partow , Marin David , Popat Uday R. , Andersson Borje S. , Shpall Elizabeth J. , Jabbour Elias , Daver Naval , Andreeff Michael , Ravandi Farhad , Cortes Jorge , Patel Keyur , Champlin Richard E. , Ciurea Stefan O.
Published: January 2017

In patients with AML with FMS‐like tyrosine kinase 3 (FLT3) mutations, the significance of minimal residual disease (MRD) detected by PCR before allogeneic stem cell transplantation (SCT) on outcomes after transplant remains unclear. We identified 200 patients with FLT3‐AML who underwent SCT at our institution. Disease status at transplant was: first or second complete remission (CR1/CR2, n = 119), high‐risk CR (third or subsequent CR, marrow hypoplasia, or incomplete count recovery) (CR‐HR, n = 31), and morphological evidence of active disease (AD, n = 50). The median follow‐up was 27 months, and the 2‐year overall and progression‐free survival were 43% and 41%, respectively. Relapse was highest in the AD group (85%) and the CR‐HR FLT3 MRD positive group (72%), followed by CR‐HR FLT3 MRD negative (58%), CR1/CR2 FLT3 MRD positive (39%), and lowest in the CR1/CR2 FLT3 MRD negative group (23%). On multivariate analysis, independent factors influencing the risk of relapse were detectable morphological disease and FLT3 MRD by PCR pre‐transplant. Factors that did not influence the relapse risk included: age, graft type, graft source, type of FLT3 mutation, or conditioning intensity. Morphologic and molecular remission status at the time of transplant were key predictors of disease relapse and survival in patients with FLT3‐AML.
Asymmetric Petasis Borono‐Mannich Allylation Reactions Catalyzed by Chiral Biphenols
Authors: Jiang Yao , Schaus Scott E.
Published: January 2017

Chiral biphenols catalyze the asymmetric Petasis borono‐Mannich allylation of aldehydes and amines through the use of a bench‐stable allyldioxaborolane. The reaction proceeds via a two‐step, one‐pot process and requires 2–8 mole % of 3,3′‐Ph2‐BINOL as the optimal catalyst. Under microwave heating the reaction affords chiral homoallylic amines in excellent yields (up to 99 %) and high enantioselectivies (er up to 99:1). The catalytic reaction is a true multicomponent condensation reaction whereas both the aldehyde and the amine can possess a wide range of structural and electronic properties. Use of crotyldioxaborolane in the reaction results in stereodivergent products with anti‐ and syn‐diastereomers both in good diastereoselectivities and enantioselectivities from the corresponding E‐ and Z‐borolane stereoisomers.
Food Security, Structural Transformation, Markets and Government Policy
Authors: Timmer C. Peter
Published: January 2017

Food prices are a key signal about what is happening to food security, and two dimensions are important: their average level (and whether this is rising or falling in the long run) and their volatility. Food price instability slows down economic growth and the structural transformation that is the pathway out of rural poverty. The best approaches to improving food security depend on which global food price regime is likely to drive policy formation between now and 2050. The historical path of structural transformation with falling food prices, leading to a ‘world without agriculture’, is an obvious possibility. But continued financial instability, coupled with the impact of climate change, could lead to a new and uncertain path of rising real costs for food, with a reversal of structural transformation. Management of food policy, and the outlook for sustained poverty reduction, will be radically different depending on which of these global price regimes plays out.
Assessing the Efficiency Costs of Vietnam's ‘Missing’ Small and Medium Sized Enterprises: A Panel Data Investigation
Authors: Le Trung Dang , Shaffer Paul
Published: January 2017

This article investigates whether there are efficiency costs associated with the pronounced rightward skew in the firm size distribution, or Vietnam's ‘missing small and medium size enterprise (SMEs)’, drawing on panel data analysis of firm growth and survival. Specifically, it examines if factor allocation biases with respect to credit, preferable treatment of state owned enterprises, barriers to entry into export markets and economies of scale are important determinants of growth rates and survival probabilities of small, medium and large‐sized firms. Overall, findings on the earlier variables do not support the view that there are large efficiency costs associated with Vietnam's ‘missing SMEs’. Together with other results in the literature with do not find significant equity costs associated with Vietnam's ‘missing SMES’, these findings raise questions about policy initiatives in support of SMEs in Vietnam, such as the National SME Support program, in particular, through improved access to credit.
Cytotoxic Triterpenoids from the Barks of Betula platyphylla var. japonica
Authors: Eom Hee Jeong , Kang Hee Rae , Choi Sang Un , Kim Ki Hyun
Published: January 2017

Phytochemical investigation on the barks of Betula platyphylla var. japonica (Betulaceae) was carried out, resulting in the isolation and identification of three new triterpenoids, 27‐O‐cis‐caffeoylcylicodiscic acid (1), 27‐O‐cis‐feruloylcylicodiscic acid (2), and 27‐O‐cis‐caffeoylmyricerol (3), along with six known triterpenoids, obtusilinin (4), winchic acid (5), 27‐O‐trans‐caffeoylcylicodiscic acid (6), uncarinic acid E (7), myriceric acid B (8), and 3‐O‐trans‐caffeoyloleanolic acid (9). The structures of the new compounds were elucidated by extensive spectroscopic methods, including 1D‐ and 2D‐NMR, and HR‐ESI‐MS. All of the isolated compounds were evaluated for cytotoxicity against four human tumor cell lines (A549, SK‐OV‐3, SK‐MEL‐2, and Bt549). Compounds 2, 6, 8, and 9 exhibited potent cytotoxicity against all of the tumor cells tested (IC50 < 10.0 μm), while compounds 3, 4, 5, and 7 showed moderate cytotoxicity against all of the tumor cells tested (IC50 < 20.0 μm).
Mitochondrial ryanodine‐sensitive Ca2+ channels of rat liver
Authors: Kupynyak N.I. , Ikkert O.V. , Shlykov S.G. , Babich L.G. , Manko V.V.
Published: January 2017

To examine ryanodine‐sensitive Ca2+ channels in mitochondria of rat hepatocytes and their role in energy state of the cells via investigation of the ryanodine effect on mitochondrial membrane potential.

Oxygen consumption was measured by polarography using the Clark electrode. The substrates of oxidation such as pyruvate (5mM), α‐ketoglutarate (5mM), or succinate (5mM) were used. Oxidative phosphorylation was stimulated by the addition of adenosine diphosphate (200nM). Mitochondrial membrane potential was measured using a voltage‐sensitive fluorescent probe tetramethylrhodamine‐methyl‐ester (0.1μM) and was analyzed by a flow cytometer. To evaluate the intact mitochondria, we used carbonil cyanide m‐chlorophenyl hydrazone (CCCP, 10μM). Changes in the ionized calcium concentration in rat liver mitochondria were measured using a fluorescent probe Fluo‐4 AM.

Effect of ryanodine on oxygen consumption of rat liver mitochondria depends on the oxidation substrate and the incubation time. Oxidation of pyruvate in the presence of ryanodine (0.05μM) decreased the membrane potential of rat liver mitochondria by 38.4%. At higher concentrations, ryanodine (0.1μM or 1μM) led to decrease of membrane potential by 51.7% and 42.8%, respectively. In contrast, oxidation of α‐ketoglutarate in the presence of ryanodine (0.05μM) increased mitochondrial membrane potential by 16.8%. However, at higher concentrations, ryanodine (0.1μM or 1μM) triggered a decreasing of membrane potential by 42.5% and 31.0%, respectively. Therefore, ryanodine at various concentrations (0.05μM, 0.1μM, or 1μM) causes differential effects on Ca2+ concentration in the mitochondria matrix under oxidation of pyruvate or α‐ketoglutarate.

The data suggest the presence of ryanodine receptors in mitochondrial membrane of rat hepatocytes. Their inhibition with higher concentrations of ryanodine leads to decreasing of intra‐mitochondrial Ca2+ concentration and affecting the energy state of mictochondria in hepatocytes.
Versatile Interacting Peptide (VIP) Tags for Labeling Proteins with Bright Chemical Reporters
Authors: Zane Hannah K. , Doh Julia K. , Enns Caroline A. , Beatty Kimberly E.
Published: January 2017

Fluorescence microscopy is an essential tool for the biosciences, enabling the direct observation of proteins in their cellular environment. New methods that facilitate attachment of photostable synthetic fluorophores with genetic specificity are needed to advance the frontiers of biological imaging. Here, we describe a new set of small, selective, genetically encoded tags for proteins based on a heterodimeric coiled‐coil interaction between two peptides: CoilY and CoilZ. Proteins expressed as a fusion to CoilZ were selectively labeled with the complementary CoilY fluorescent probe peptide. Fluorophore‐labeled target proteins were readily detected in cell lysates with high specificity and sensitivity. We found that these versatile interacting peptide (VIP) tags allowed rapid and specific delivery of bright organic dyes or quantum dots to proteins displayed on living cells. Additionally, we validated that either CoilY or CoilZ could serve as the VIP tag, which enabled us to observe two distinct cell‐surface protein targets with this one heterodimeric pair.
Hydrosilylation of RN=CH Imino‐Substituted Pyridines without a Catalyst
Authors: Novák Miroslav , Hošnová Hana , Dostál Libor , Glowacki Britta , Jurkschat Klaus , Lyčka Antonín , Ruzickova Zdenka , Jambor Roman
Published: January 2017

Treatment of the neutral pyridine‐based ligands L1–L3, bearing either one or two RN=CH imine moieties {where L1 and L2 are N,N‐chelating ligands 2‐(RN=CH)C5H4N (R=Ph (L1) or R=2,4,6‐Ph3C6H2 (L2)) and L3 is the N,N,N‐chelating ligand 2,6‐(RN=CH)2C5H3N (R=2,6‐iPr2C6H3)}, with HSiCl3 yielded N→Si‐coordinated silicon(IV) amides 2‐{Cl3SiN(R)CH2}C5H4N (1, R=Ph; 2, R=2,4,6‐Ph3C6H2) and 2‐{Cl3SiN(R)CH2}‐6‐(RN=CH)C5H4N (3, R=2,6‐iPr2C6H3). The organosilicon amides 1–3 are the products of spontaneous hydrosilylation of the RN=CH imine moiety induced by N→Si coordination of the proposed N,N‐chelated chlorosilanes L1→SiHCl3 (1 a), L2→SiHCl3 (2 a), and L3→SiHCl3 (3 a). Furthermore, the reaction of L3 with an excess of HSiCl3 provided the intramolecularly coordinated chlorosilicon diamide cyclo‐{(C5H3N)‐1,3‐(CH2NR)2}SiCl2 (4) (R=2,6‐iPr2C6H3) as the product of spontaneous reduction of both RN=CH imine moieties. The compounds have been characterized by NMR spectroscopy (1–4) and single‐crystal X‐ray diffraction analysis (1, 3, and 4). The mechanism of the hydrosilylation of the second RN=CH imine moiety in 3 by an excess of SiHCl3 has also been studied. The experimental work is supplemented by DFT calculations.
Structural Dimorphism of Achiral α,γ‐Hybrid Peptide Foldamers: Coexistence of 12‐ and 15/17‐Helices
Authors: Misra Rajkumar , Saseendran Abhijith , George Gijo , Veeresh Kuruva , Raja K. Muruga Poopathi , Raghothama Srinivasarao , Hofmann Hans‐Jörg , Gopi Hosahudya N.
Published: January 2017

Here, novel 12‐helices in α,γ‐hybrid peptides composed of achiral α‐aminoisobutyric acid (Aib) and 4‐aminoisocaproic acid (Aic, doubly homologated Aib) monomers in 1:1 alternation are reported. The 12‐helices were indicated by solution and crystal structural analyses of tetra‐ and heptapeptides. Surprisingly, single crystals of the longer nonapeptide displayed two different helix types: the novel 12‐helix and an unprecedented 15/17‐helix. Quantum chemical calculations on both helix types in a series of continuously lengthened Aib/Aic‐hybrid peptides confirm that the 12‐helix is more stable than the 15/17‐helix in shorter peptides, whereas the 15/17‐helix is more stable in longer sequences. Thus, the coexistence of both helix types can be expected within a definite range of sequence lengths. The novel 15/17‐ and 12‐helices in α,γ‐hybrid peptides with 5→1 and 4→1 hydrogen‐bonding patterns, respectively, can be viewed as backbone‐expanded analogues of native α‐ and 310‐helices.
Characterization of Metal Artifacts in X‐Ray Computed Tomography
Authors: Park Hyoung Suk , Choi Jae Kyu , Seo Jin Keun
Published: January 2017

Metal streak artifacts in X‐ray computerized tomography (CT) are characterized here using the notion of the wavefront set from microlocal analysis. The metal artifacts are caused mainly from the mismatch of the forward model of the filtered back‐projection; the presence of metallic subjects in an imaging subject violates the model's assumption of the CT sinogram data being the Radon transform of an image. The increasing use of metallic implants has increased demand for the reduction of metal artifacts in the field of dental and medical radiography. However, it is a challenging issue due to the serious difficulties in analyzing the X‐ray data, which depends nonlinearly on the distribution of the metallic subject. In this paper, we, for the first time, provide a mathematical analysis to characterize the structure of metal streaking artifacts. The metal streaking artifacts are produced along the line tangent to boundaries of the metal region touching at least two different boundaries. We also found a sufficient condition for the nonexistence of the metal streaking artifacts. © 2017 Wiley Periodicals, Inc.
Flexible Viologen Cyclophanes: Odd/Even Effects on Intramolecular Interactions
Authors: Berville Mathilde , Choua Sylvie , Gourlaouen Christophe , Boudon Corinne , Ruhlmann Laurent , Bailly Corinne , Cobo Saioa , Saint‐Aman Eric , Wytko Jennifer , Weiss Jean
Published: January 2017

The ability of three bis‐viologen cyclophanes to act as redox‐triggered contractile switches is investigated. Odd/even effects in the formation of cyclic bis‐viologens are circumvented by the use of a Zincke salt intermediate and a tetrathiafulvalene template to prepare a flexible cyclophane with hexyl linkers. Comparative spectro‐electrochemical studies of this macrocycle with two other pentyl‐ or heptyl‐linked cyclic bis‐viologens show that the development of intramolecular interactions in aqueous solution depends on the length of the bridges. This dependence is confirmed by EPR and DFT studies of the magnetic coupling in the diradical dication species. The anti‐ferromagnetic or ferromagnetic nature of the coupling depend, respectively, on the odd or even number of methylene groups in the spacer.
IRBAS: An online database to collate, analyze, and synthesize data on the biodiversity and ecology of intermittent rivers worldwide
Authors: Leigh Catherine , Laporte Baptiste , Bonada Núria , Fritz Ken , Pella Hervé , Sauquet Eric , Tockner Klement , Datry Thibault
Published: January 2017

Key questions dominating contemporary ecological research and management concern interactions between biodiversity, ecosystem processes, and ecosystem services provision in the face of global change. This is particularly salient for freshwater biodiversity and in the context of river drying and flow‐regime change. Rivers that stop flowing and dry, herein intermittent rivers, are globally prevalent and dynamic ecosystems on which the body of research is expanding rapidly, consistent with the era of big data. However, the data encapsulated by this work remain largely fragmented, limiting our ability to answer the key questions beyond a case‐by‐case basis. To this end, the Intermittent River Biodiversity Analysis and Synthesis (IRBAS; http://irbas.cesab.org) project has collated, analyzed, and synthesized data from across the world on the biodiversity and environmental characteristics of intermittent rivers. The IRBAS database integrates and provides free access to these data, contributing to the growing, and global, knowledge base on these ubiquitous and important river systems, for both theoretical and applied advancement. The IRBAS database currently houses over 2000 data samples collected from six countries across three continents, primarily describing aquatic invertebrate taxa inhabiting intermittent rivers during flowing hydrological phases. As such, there is room to expand the biogeographic and taxonomic coverage, for example, through addition of data collected during nonflowing and dry hydrological phases. We encourage contributions and provide guidance on how to contribute and access data. Ultimately, the IRBAS database serves as a portal, storage, standardization, and discovery tool, enabling collation, synthesis, and analysis of data to elucidate patterns in river biodiversity and guide management. Contribution creates high visibility for datasets, facilitating collaboration. The IRBAS database will grow in content as the study of intermittent rivers continues and data retrieval will allow for networking, meta‐analyses, and testing of generalizations across multiple systems, regions, and taxa.
Highly Sensitive Electrochemical Hydrogen Peroxide Sensor Based on Iron Oxide‐Reduced Graphene Oxide‐Chitosan Modified with DNA‐Celestine Blue
Authors: Noorbakhsh Abdollah , Khakpoor Mohmmad , Rafieniya Mohammad , Sharifi Ensiyeh , Mehrasa Mohammad
Published: January 2017

The present study describes a novel and very sensitive electrochemical assay for determination of hydrogen peroxide (H2O2) based on synergistic effects of reduced graphene oxide‐ magnetic iron oxide nanocomposite (rGO‐Fe3O4) and celestine blue (CB) for electrochemical reduction of H2O2. rGO‐Fe3O4 nanocomposite was synthesized and characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X‐ray diffraction (XRD), electrochemical impedance spectroscopy and cyclic voltammetry. Chitosan (Chit) was used for immobilization of amino‐terminated single‐stranded DNA (ss‐DNA) molecules via a glutaraldehyde (GA) to the surface of rGO‐Fe3O4. The MTT (3‐(4,5‐Dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide) results confirmed the biocompatibility of nanocomposite. Experimental parameters affecting the ss‐DNA molecules immobilization were optimized. Finally, by accumulation of the CB on the surface of the rGO‐Fe3O4‐Chit/ssDNA, very sensitive amperometric H2O2 sensor was fabricated. The electrocatalytic activity of the rGO‐Fe3O4‐Chit/DNA‐CB electrode toward H2O2 reduction was found to be very efficient, yielding very low detection limit (DL) of 42 nM and a sensitivity of 8.51 μA/μM. Result shows that complex matrices of the human serum samples did not interfere with the fabricated sensor. The developed sensor provided significant advantages in terms of low detection limit, high stability and good reproducibility for detection of H2O2 in comparison with recently reported electrochemical H2O2 sensors.
Preliminary techno‐economic analysis of a multi‐bed series reactor as a simultaneous CF4 abatement and utilization process
Authors: Lee Boreum , Jeong Seonju , Lee Sunggeun , Jung Ho‐Young , Ryi Shin‐Kun , Lim Hankwon
Published: January 2017

A preliminary techno‐economic analysis combining process simulation and economic analysis has been carried out to assess the feasibility of employing a new CF4 abatement and utilization process without HF effluent, where CaO was employed to convert produced HF into CaF2, a useful chemical. Moreover, the effect of employing multi‐bed series reactors compared with a single‐bed reactor on CaF2 production was analyzed using Aspen HYSYS® based on material and energy balances from process flow diagrams for three systems, a single‐bed reactor (S‐1), a two‐bed series reactor (S‐2), and a three‐bed series reactor (S‐3). From economic analysis to estimate annual operating cost savings for three systems, it was found that multi‐bed series reactors (S‐2 and S‐3) performed better than a single‐bed reactor (S‐1) due to equilibrium shift by Le Chatelier's principle leading to reduced operating temperatures to produce the same amount of CaF2 as S‐1. Consequently, annual cost savings of about 7 to 13% were obtained in S‐2 and S‐3 compared to S‐1 and this can serve as a useful guideline for the efficient system design. © 2017 Society of Chemical Industry and John Wiley & Sons, Ltd.
Correspondence between evoked and intrinsic functional brain network configurations
Authors: Bolt Taylor , Nomi Jason S. , Rubinov Mikail , Uddin Lucina Q.
Published: January 2017

Much of the literature exploring differences between intrinsic and task‐evoked brain architectures has examined changes in functional connectivity patterns between specific brain regions. While informative, this approach overlooks important overall functional changes in hub organization and network topology that may provide insights about differences in integration between intrinsic and task‐evoked states. Examination of changes in overall network organization, such as a change in the concentration of hub nodes or a quantitative change in network organization, is important for understanding the underlying processes that differ between intrinsic and task‐evoked brain architectures. The present study used graph‐theoretical techniques applied to publicly available neuroimaging data collected from a large sample of individuals (N = 202), and a within‐subject design where resting‐state and several task scans were collected from each participant as part of the Human Connectome Project. We demonstrate that differences between intrinsic and task‐evoked brain networks are characterized by a task‐general shift in high‐connectivity hubs from primarily sensorimotor/auditory processing areas during the intrinsic state to executive control/salience network areas during task performance. In addition, we demonstrate that differences between intrinsic and task‐evoked architectures are associated with changes in overall network organization, such as increases in network clustering, global efficiency and integration between modules. These findings offer a new perspective on the principles guiding functional brain organization by identifying unique and divergent properties of overall network organization between the resting‐state and task performance. Hum Brain Mapp 38:1992–2007, 2017. © 2017 Wiley Periodicals, Inc.
Frontoparietal activation during visual conjunction search: Effects of bottom‐up guidance and adult age
Authors: Madden David J. , Parks Emily L. , Tallman Catherine W. , Boylan Maria A. , Hoagey David A. , Cocjin Sally B. , Johnson Micah A. , Chou Ying‐hui , Potter Guy G. , Chen Nan‐kuei , Packard Lauren E. , Siciliano Rachel E. , Monge Zachary A. , Diaz Michele T.
Published: January 2017

We conducted functional magnetic resonance imaging (fMRI) with a visual search paradigm to test the hypothesis that aging is associated with increased frontoparietal involvement in both target detection and bottom‐up attentional guidance (featural salience). Participants were 68 healthy adults, distributed continuously across 19 to 78 years of age. Frontoparietal regions of interest (ROIs) were defined from resting‐state scans obtained prior to task‐related fMRI. The search target was defined by a conjunction of color and orientation. Each display contained one item that was larger than the others (i.e., a size singleton) but was not informative regarding target identity. Analyses of search reaction time (RT) indicated that bottom‐up attentional guidance from the size singleton (when coincident with the target) was relatively constant as a function of age. Frontoparietal fMRI activation related to target detection was constant as a function of age, as was the reduction in activation associated with salient targets. However, for individuals 35 years of age and older, engagement of the left frontal eye field (FEF) in bottom‐up guidance was more prominent than for younger individuals. Further, the age‐related differences in left FEF activation were a consequence of decreasing resting‐state functional connectivity in visual sensory regions. These findings indicate that age‐related compensatory effects may be expressed in the relation between activation and behavior, rather than in the magnitude of activation, and that relevant changes in the activation‐RT relation may begin at a relatively early point in adulthood. Hum Brain Mapp 38:2128–2149, 2017. © 2017 Wiley Periodicals, Inc.
Do Targeted Reproductive Health Services Matter? – The Impact of a Midwife Program in Indonesia
Authors: Strupat Christoph
Published: January 2017

This paper examines empirically whether midwives, as an integral part of the reproductive health and family planning programs in Indonesia, are effective in advising young women to delay their first birth and also influence the decision on post‐primary school attendance. Using the Indonesian Family Life Survey, I investigate the extent to which the expansion of a midwife program affects the age at first birth and the number of school years of women. My findings suggest that women who were exposed to a midwife when they have to decide on further school attendance (aged 13–20 years) delay their first birth and also stay longer in school. According to the average returns of education in Indonesia, I conclude that reproductive health services provided by midwives can generate large socioeconomic benefits by allowing young women to postpone their first birth. Copyright © 2017 John Wiley & Sons, Ltd.
ESES: Software for Eulerian solvent excluded surface
Authors: Liu Beibei , Wang Bao , Zhao Rundong , Tong Yiying , Wei Guo‐Wei
Published: January 2017

Solvent excluded surface (SES) is one of the most popular surface definitions in biophysics and molecular biology. In addition to its usage in biomolecular visualization, it has been widely used in implicit solvent models, in which SES is usually immersed in a Cartesian mesh. Therefore, it is important to construct SESs in the Eulerian representation for biophysical modeling and computation. This work describes a software package called Eulerian solvent excluded surface (ESES) for the generation of accurate SESs in Cartesian grids. ESES offers the description of the solvent and solute domains by specifying all the intersection points between the SES and the Cartesian grid lines. Additionally, the interface normal at each intersection point is evaluated. Furthermore, for a given biomolecule, the ESES software not only provides the whole surface area, but also partitions the surface area according to atomic types. Homology theory is utilized to detect topological features, such as loops and cavities, on the complex formed by the SES. The sizes of loops and cavities are measured based on persistent homology with an evolutionary partial differential equation‐based filtration. ESES is extensively validated by surface visualization, electrostatic solvation free energy computation, surface area and volume calculations, and loop and cavity detection and their size estimation. We used the Amber PBSA test set in our electrostatic solvation energy, area, and volume validations. Our results are either calibrated by analytical values or compared with those from the MSMS software. © 2017 Wiley Periodicals, Inc.
Lumbar spine postures in Marines during simulated operational positions
Authors: Berry David B. , Rodríguez‐Soto Ana E. , Su Jeannie , Gombatto Sara P. , Shahidi Bahar , Palombo Laura , Chung Christine , Jensen Andrew , Kelly Karen R. , Ward Samuel R.
Published: January 2017

Low back pain has a 70% higher prevalence in members of the armed forces than in the general population, possibly due to the loads and positions soldiers experience during training and combat. Although the influence of heavy load carriage on standing lumbar spine posture in this population is known, postures in other operationally relevant positions are unknown. Therefore, the purpose of this study was to characterize the effect of simulated military operational positions under relevant loading conditions on global and local lumbar spine postures in active duty male US Marines. Secondary objectives were to evaluate if intervertebral disc degeneration and low back pain affect lumbar spine postures. Magnetic resonance images were acquired on an upright scanner in the following operational positions: Natural standing with no external load, standing with body armor (11.3 kg), sitting with body armor, and prone on elbows with body armor. Custom software was used to measure global lumbar spine posture: Lumbosacral flexion, sacral slope, lordosis, local measures of intervertebral angles, and intervertebral distances. Sitting resulted in decreased lumbar lordosis at all levels of the spine except L1–L2. When subjects were prone on elbows, a significant increase in local lordosis was observed only at L5–S1 compared with all other positions. Marines with disc degeneration (77%) or history of low back pain (72%) had decreased lumbar range of motion and less lumbar extension than healthy Marines. These results indicate that a male Marine's pathology undergoes a stereotypic set of postural changes during functional tasks, which may impair performance. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2145–2153, 2017.
Positive outcomes following gait therapy intervention for hip osteoarthritis: A longitudinal study
Authors: Solomonow‐Avnon Deborah , Herman Amir , Levin Daniel , Rozen Nimrod , Peled Eli , Wolf Alon
Published: January 2017

Footwear‐generated biomechanical manipulation of lower‐limb joints was shown to beneficially impact gait and quality of life in knee osteoarthritis patients, but has not been tested in hip osteoarthritis patients. We examined a customized gait treatment program using a biomechanical device shown in previous investigations to be capable of manipulating hip biomechanics via foot center of pressure (COP) modulation. The objective of this study was to assess the treatment program for hip osteoarthritis patients, enrolled in a 1‐year prospective investigation, by means of objective gait and spatiotemporal parameters, and subjective quality of life measures. Gait analysis and completion of questionnaires were performed at the start of the treatment (baseline), and after 3, 6, and 12 months. Outcome parameters were evaluated over time using linear mixed effects models, and association between improvement in quality of life measures and change in objective outcomes was tested using mixed effect linear regression models. Quality of life measures improved compared to baseline, accompanied by increased gait speed and cadence. Sagittal‐plane hip joint kinetics, kinematics, and spatiotemporal parameters changed throughout the study compared to baseline, in a manner suggesting improvement of gait. The most substantial improvement occurred within 3 months after treatment initiation, after which improvement approximately plateaued, but was sustained at 12 months. Speed and cadence, as well as several sagittal‐plane gait parameters, were significant predictors of improvement in quality of life. Clinical significance: Evidence suggests that a biomechanical gait therapy program improves subjective and objective outcomes measures and is a valid treatment option for hip osteoarthritis. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2222–2232, 2017.
Transoral submandibulotomy for deep hilar submandibular gland sialolithiasis
Authors: Schapher Mirco , Mantsopoulos Konstantinos , Messbacher Maria‐Elena , Iro Heinrich , Koch Michael
Published: January 2017

Objectives/Hypothesis

To assess the long‐term results after transoral submandibulotomy for stones located in the deep hilar and intraparenchymal submandibular region.

Study Design

Retrospective cohort analysis.

Methods

Retrospective evaluation including all patients treated with transoral submandibulotomy for sialolithiasis at a tertiary referral center.

Results

Complete stone removal at the first transoral surgical treatment was achieved in 185 of 234 patients (79.1%). One hundred seventy‐five of the 234 patients were followed up for a mean of 31.2 ( ± 20.5) months. During the follow‐up period, 140 of the 175 patients (80.0%) became symptom free after one operation. In patients with residual symptoms, no further treatment was needed in 12 patients (6.9%) due to the mildness of the symptoms; 23 patients (13.1%) received further therapy, which was successful in 15 cases. Submandibulectomy only had to be performed in 3.4% of the patients with follow‐up (6/175). In a questionnaire survey, 91.4% of the patients stated that they would be prepared to have the same operation again.

Conclusions

These findings show that transoral removal of submandibular sialoliths located in the deep hilum or adjacent intraglandular parenchyma is an effective treatment that can be assisted by additional measures. The techniques described show high success rates, good long‐term results, low complication rates, and they avoided the need for submandibulectomy in >95% of cases.

Level of Evidence

4. Laryngoscope, 127:2038–2044, 2017
P21‐activated kinase 1 regulates resistance to BRAF inhibition in human cancer cells
Authors: Babagana Mahamat , Johnson Sydney , Slabodkin Hannah , Bshara Wiam , Morrison Carl , Kandel Eugene S.
Published: January 2017

BRAF is a commonly mutated oncogene in various human malignancies and a target of a new class of anti‐cancer agents, BRAF‐inhibitors (BRAFi). The initial enthusiasm for these agents, based on the early successes in the management of metastatic melanoma, is now challenged by the mounting evidence of intrinsic BRAFi‐insensitivity in many BRAF‐mutated tumors, by the scarcity of complete responses, and by the inevitable emergence of drug resistance in initially responsive cases. These setbacks put an emphasis on discovering the means to increase the efficacy of BRAFi and to prevent or overcome BRAFi‐resistance. We explored the role of p21‐activated kinases (PAKs), in particular PAK1, in BRAFi response. BRAFi lowered the levels of active PAK1 in treated cells. An activated form of PAK1 conferred BRAFi‐resistance on otherwise sensitive cells, while genetic or pharmacologic suppression of PAK1 had a sensitizing effect. While activation of AKT1 and RAC1 proto‐oncogenes increased BRAFi‐tolerance, the protective effect was negated in the presence of PAK inhibitors. Furthermore, combining otherwise ineffective doses of PAK‐ and BRAF‐inhibitors synergistically affected intrinsically BRAFi‐resistant cells. Considering the high incidence of PAK1 activation in cancers, our findings suggests PAK inhibition as a strategy to augment BRAFi therapy and overcome some of the well‐known resistance mechanisms.