bluuebunny/crossref_metadata_2025 huggingface dataset:
Northward shift of the agricultural climate zone under 21st-century global climate change
Authors: King Myron , Altdorff Daniel , Li Pengfei , Galagedara Lakshman , Holden Joseph , Unc Adrian
Published: May 2018

As agricultural regions are threatened by climate change, warming of high latitude regions and increasing food demands may lead to northward expansion of global agriculture. While socio-economic demands and edaphic conditions may govern the expansion, climate is a key limiting factor. Extant literature on future crop projections considers established agricultural regions and is mainly temperature based. We employed growing degree days (GDD), as the physiological link between temperature and crop growth, to assess the global northward shift of agricultural climate zones under 21st-century climate change. Using ClimGen scenarios for seven global climate models (GCMs), based on greenhouse gas (GHG) emissions and transient GHGs, we delineated the future extent of GDD areas, feasible for small cereals, and assessed the projected changes in rainfall and potential evapotranspiration. By 2099, roughly 76% (55% to 89%) of the boreal region might reach crop feasible GDD conditions, compared to the current 32%. The leading edge of the feasible GDD will shift northwards up to 1200 km by 2099 while the altitudinal shift remains marginal. However, most of the newly gained areas are associated with highly seasonal and monthly variations in climatic water balances, a critical component of any future land-use and management decisions.
Carrier thermometry of cold ytterbium atoms in an optical lattice clock
Authors: Han Chengyin , Zhou Min , Zhang Xiaohang , Gao Qi , Xu Yilin , Li Shangyan , Zhang Shuang , Xu Xinye
Published: May 2018

The ultracold atomic gas serving as the quantum reference is a key part of an optical lattice clock, and the temperature of atoms in the optical lattice affects the uncertainty and instability of the optical lattice clocks. Since the carrier spectrum of the clock transition in the lattices reflects the thermal dynamics of cold atoms, the temperature of atoms can be extracted from the carrier spectrum in a non-magic wavelength lattice of ytterbium optical clocks. Furthermore, the temperatures obtained from the carrier spectra are in good agreement with the results obtained by the time-of-flight method and thermometry based on the sideband spectrum. In addition, the heating effects caused by the lattice laser are studied on the basis of the sample temperatures.
A novel microRNA signature predicts survival in liver hepatocellular carcinoma after hepatectomy
Authors: Fu Qiang , Yang Fan , Xiang Tengxiao , Huai Guoli , Yang Xingxing , Wei Liang , Yang Hongji , Deng Shaoping
Published: May 2018

Liver hepatocellular carcinoma (LIHC) is the most common type of primary liver cancer. In the current study, genome-wide miRNA-Seq and mRNA profiles in 318 LIHC patients derived from The Cancer Genome Atlas (TCGA) were analysed to identify miRNA-based signatures for LIHC prognosis with survival analysis and a semi-supervised principal components (SPC) method. A seven-miRNA signature was confirmed for overall survival (OS) prediction by comparing miRNA profiles in paired primary tumour and solid tumour normal tissues. Thereafter, a linear prognostic model that consisted of seven miRNAs was established and used to divide patients into high- and low-risk groups according to prognostic scores. Subsequent Kaplan-Meier analysis revealed that the seven-miRNA signature correlated with a good predictive clinical outcome for 5-year survival in LIHC patients. Additionally, this miRNA-based prognostic model could also be used for OS prognosis of LIHC patients in early stages, which could guide the future therapy of those patients and promote the OS rate. Moreover, the seven-miRNA signature was an independent prognostic factor. In conclusion, this signature may serve as a prognostic biomarker and guide LIHC therapy, and it could even be used as an LIHC therapeutic target in the future.
Pyrenyl-carbon nanostructures for scalable enzyme electrocatalysis and biological fuel cells
Authors: Krishnan Sadagopan , Frazis Michael , Premaratne Gayan , Niroula Jinesh , Echeverria Elena , McIlroy David N.
Published: May 2018

A large electrode geometric area-based pyrenyl carbon nanostructure modification for scale-up of electrocatalytic currents and power using hydrogenase anode and bilirubin oxidase cathode is demonstrated.
Photochemical reductive homologation of hydrogen cyanide using sulfite and ferrocyanide
Authors: Xu Jianfeng , Ritson Dougal J. , Ranjan Sukrit , Todd Zoe R. , Sasselov Dimitar D. , Sutherland John D.
Published: May 2018

On their own, neither sulfite nor ferrocyanide are efficient sources of photochemically-generated electrons for the reductive homologation of hydrogen cyanide, but together they are.
Rational design of a neutral pH functional and stable organic photocathode
Authors: Francàs Laia , Burns Eric , Steier Ludmilla , Cha Hyojung , Solà-Hernández Lluís , Li Xiaoe , Shakya Tuladhar Pabitra , Bofill Roger , García-Antón Jordi , Sala Xavier , Durrant James R.
Published: May 2018

Rational design and preparation of an organic photocathode which produces hydrogen for more than 5 hours under 0 VRHE and one sun.
Ligand-promoted ruthenium-catalyzed meta C–H chlorination of arenes using N-chloro-2,10-camphorsultam
Authors: Fan Zhoulong , Lu Heng , Cheng Zhen , Zhang Ao
Published: May 2018

A practical meta C–H chlorination protocol is established via a Ru(0)-catalyzed ortho-metalation strategy.
Hydrothermal synthesis of a rutile/anatase TiO2mixed crystal from potassium titanyl oxalate: crystal structure and formation mechanism
Authors: Hu Kangkai , E Lei , Zhao Dan , Hu Chaoyang , Cui Jin , Lai Liuyuan , Xiong Qiumin , Liu Zhifeng
Published: May 2018

Nowadays, rutile TiO2or anatase TiO2is prepared from titanium oxalate, but there are only few studies on the rutile/anatase TiO2mixed crystal.
Influence of the negative charge density of metalate nanosheets on their bottom-up synthesis
Authors: Ban Takayuki , Wakita Takahiro , Yokoyama Ryo , Miyake Tatsuya , Ohya Yutaka
Published: May 2018

Low negative charge density is required for the bottom-up synthesis of metalate nanosheets by an aqueous solution process.
Origin of gypsum growth habit difference as revealed by molecular conformations of surface-bound citrate and tartrate
Authors: Chen Wei , Zhao Weilong , Wu Yi-nan , Wang Ying , Zhang Bingru , Li Fengting , Chen Qian , Qi Zeming , Xu Zhijun
Published: May 2018

Correlation of the microscopic gypsum–organic interfacial structural information with the macroscopic crystal morphology difference induced by different organic acids.
The predictive power of aromaticity: quantitative correlation between aromaticity and ionization potentials and HOMO–LUMO gaps in oligomers of benzene, pyrrole, furan, and thiophene
Authors: Gershoni-Poranne Renana , Rahalkar Anuja P. , Stanger Amnon
Published: May 2018

The aromaticity of oligomers predicts their HOMO–LUMO gaps and ionization potentials.
Pressure-induced switching properties of the iron(iii) spin-transition complex [FeIII(3-OMeSalEen)2]PF6
Authors: Laisney J. , Shepherd H. J. , Rechignat L. , Molnár G. , Rivière E. , Boillot M.-L.
Published: May 2018

The volume-dependent properties of a spin-crossover Fe(iii) prototypical compound revealed by combined magnetic, vibrational and structural investigations of the pressure effect.
A robust Zn(ii)/Na(i)-MOF decorated with [(OAc)2(H2O)2]n2n− anions for the luminescence sensing of copper ions based on the inner filter effect
Authors: Liu Lei-Lei , Yu You-Zhu , Zhao Xue-Jing , Wang Ya-Ru , Cheng Fei-Yang , Zhang Meng-Ke , Shu Jing-Jing , Liu Lin
Published: May 2018

A robust Zn(ii)/Na(i)-based MOF decorated with [(OAc)2(H2O)2]n2n− anions was synthesized and employed as the probe for Cu2+ detection.
Slow magnetic relaxation and luminescence properties in lanthanide(iii)/anil complexes
Authors: Maniaki Diamantoula , Mylonas-Margaritis Ioannis , Mayans Julia , Savvidou Aikaterini , Raptopoulou Catherine P. , Bekiari Vlasoula , Psycharis Vassilis , Escuer Albert , Perlepes Spyros P.
Published: May 2018

The Dy(iii) member of a family of lanthanide(iii)-anil complexes displays luminescence and exhibits slow magnetic relaxation.
The importance of configurational disorder in crystal structure prediction: the case of loratadine
Authors: Woollam Grahame R. , Neumann Marcus A. , Wagner Trixie , Davey Roger J.
Published: May 2018

A crystal structure prediction study of loratadine demonstrates the important role of experimentally observed disorder in determining the relative stability of the known monotropically related polymorphs.
Preparation and characterization of mesoporous hydroxyapatite with non-cytotoxicity and heavy metal adsorption capacity
Authors: Wijesinghe W. P. S. L. , Mantilaka M. M. M. G. P. G. , Peiris T. A. Nirmal , Rajapakse R. M. G. , Wijayantha K. G. Upul , Pitawala H. M. T. G. A. , Premachandra T. N. , Herath H. M. T. U. , Rajapakse R. P. V. J.
Published: May 2018

Mesoporous hydroxyapatite (MPHA) particles have recently gained a great deal of interest in a broad range of fields including biomedical fields, wastewater treatment and catalysis.
Solvent mediated hybrid 2D materials: black phosphorus – graphene heterostructured building blocks assembled for sodium ion batteries
Authors: Li Mengya , Muralidharan Nitin , Moyer Kathleen , Pint Cary L.
Published: May 2018

Solvent directed assembly of co-exfoliated 2D materials into heterostructured building blocks is introduced and combined with EPD to produce hybrid functional materials for stable high capacity sodium ion battery anodes.
A convergent strategy towards febrifugine and related compounds
Authors: Maiden T. M. M. , Mbelesi N. , Procopiou P. A. , Swanson S. , Harrity J. P. A.
Published: May 2018

We report a modular five step synthetic route to the febrifugines that employs 2-(chloromethyl)allyl-trimethylsilane as a conjunctive reagent for the coupling of the piperidine and quinazolinone groups.
Borophene as a promising anode material for sodium-ion batteries with high capacity and high rate capability using DFT
Authors: Liu Jianhua , Zhang Cheng , Xu Lei , Ju Shaohua
Published: May 2018

Two-dimensional boron synthesized by the chemical vapor deposition method is an atomically thin layer of boron with both light weight and metallicity.
Performance enhancement of PEDOT:poly(4-styrenesulfonate) actuators by using ethylene glycol
Authors: Terasawa Naohiro , Asaka Kinji
Published: May 2018

This paper describes the effect of ethylene glycol on the performance of actuators with poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate)/vapor-grown carbon fiber/ionic liquid/ethylene glycol structures.
Correction: Gradient-free directional cell migration in continuous microchannels
Authors: Ko Young-Gwang , Co Carlos C. , Ho Chia-Chi
Published: May 2018

Correction for ‘Gradient-free directional cell migration in continuous microchannels’ by Young-Gwang Ko et al., Soft Matter, 2013, 9, 2467–2474.
Correction: Balancing electrical and optical losses for efficient 4-terminal Si-perovskite solar cells with solution processed percolation electrodes
Authors: Ramírez Quiroz César Omar , Shen Yilei , Salvador Michael , Forberich Karen , Schrenker Nadine , Spyropoulos George D. , Heumüller Thomas , Wilkinson Benjamin , Kirchartz Thomas , Spiecker Erdmann , Verlinden Pierre J. , Zhang Xueling , Green Martin A. , Ho-Baillie Anita , Brabec Christoph J.
Published: May 2018

Correction for ‘Balancing electrical and optical losses for efficient 4-terminal Si-perovskite solar cells with solution processed percolation electrodes’ by César Omar Ramírez Quiroz et al., J. Mater. Chem. A, 2018, 6, 3583–3592.
The new normal of structure/function studies in the era of CRISPR/Cas9
Authors: Logsdon Glennis A. , Black Ben E.
Published: May 2018

Major advances in gene-editing technologies have enabled the rapid dissection of proteins in complex biological systems, facilitating biological experiments to complement biochemical studies with purified components. In this editorial, we highlight CRISPR/Cas9-based strategies to rapidly manipulate endogenous genes — strategies that have already transformed functional studies of proteins in metazoan systems. We further describe emerging tools using a catalytically dead version of Cas9 (dCas9) that do not cleave DNA, but can alter gene expression and/or local chromatin states, edit single nucleotide bases, and permit the visualization of specific genomic loci. Looking to the not-too-distant future, CRISPR/Cas9-based methodologies promise to lead to discoveries of new biology, opening the door for bold new synthetic biology platforms.
Capacity and outage probability analysis of asymmetric dual‐hop RF–FSO communication systems
Authors: Palliyembil Vineeth , Vellakudiyan Jagadeesh , Muthuchidamdaranathan Palanivel , Tsiftsis Theodoros A.
Published: May 2018

Free space optical (FSO) communication systems have high bandwidth, cost effectiveness and can provide secure wireless communication service for users. They can also form asymmetric dual‐hop cooperative communication links by multiplexing numerous radio frequency (RF) users by using amplify–forward transmissions over the FSO channel after converting to optical signals. In this study, an asymmetric dual‐hop RF–FSO system is studied where the RF links follow the well‐known Nakagami‐m fading distribution and the FSO channel is efficiently modelled by the Málaga turbulence fading. The performance of the system is studied by deriving the closed‐form expressions for the outage probability and ergodic channel capacity together with their asymptotic analysis at high signal‐to‐noise ratio. The numerical results are corroborated by Matlab analytical plots.
Non‐best user association scheme and effect on multiple tiers heterogeneous networks
Authors: Jia Xiangdong , Ji Shanshan , Ouyang Yuhua , Zhou Meng , Yang Longxiang
Published: May 2018

A novel mth best average biased received power (ABRP) user association (UA) scheme is proposed for K‐tier heterogeneous networks, where a user is associated with the closest base station (BS) of the kth tier having the mth strongest ABRP, . By using stochastic geometry and Poisson point processes, the authors perform the analysis of the UA probability that a typical user is associated with a BS that has the mth strongest ABRP as well as the downlink signal‐to‐interference‐noise ratio (SINR) coverage performance. The obtained results show that, for a given tier k, when the layer's position in the ordered set of ABRPs is not equal to m and the power or density of BSs is relatively small, i.e., , the UA probability increases monotonically with or . Contrarily, it decreases. For the other UA probabilities, the opposite results are achieved. Additionally, the results also show that the coverage probability of the downlink SINR of the tier k always increases with power , which is consistent with the one in the conventionally best ABRP scheme. However, for other tiers, the corresponding downlink SINR coverage probabilities do not behave monotonically with the power .
Compensation of filter cascading effects and non‐linearities in flexible multi‐carrier‐based optical networks using a complex‐kernel‐based support vector machine
Authors: Jarajreh Mutsam A.
Published: May 2018

Filter cascading effects are identified and compensated in flexible coherent multi‐carrier optical networks using, for the first time, a complex‐valued support vector machine (C‐SVM) non‐linear equaliser which is compared to phase‐conjugated subcarrier‐coding (PC‐SC)‐based non‐linearity compensation. The transmission performance of super‐channel‐based dual‐polarisation coherent multi‐band optical OFDM (DP‐MB‐OFDM) is analysed in a flexible network with two‐stage wavelength selective‐switch reconfigurable optical add‐drop multiplexer for coarse and fine switching granularity. It is shown that filter cascading effects have significant impact only on edge OFDM sub‐bands. On the other hand, C‐SVM outperforms PC‐SC resulting in an extension of the transmission‐reach, for instance, by 420 km when employing 32‐quadrature amplitude modulation at a targeted bit‐error‐rate of 10−3. This occurs since C‐SVM can compensate more effectively stochastic‐induced nonlinear cross‐talk effects. Moreover, the interplay between polarisation‐mode dispersion (PMD) and fibre non‐linearity is also investigated in DP‐MB‐OFDM, revealing that a high PMD causes time fluctuation on the non‐linear interaction affecting the balance of the ‘twin‐subcarriers’ in PS‐SC.
Control method of doubly fed wind turbine for wind speed variation based on dynamic constraints of reactive power
Authors: Ouyang Jinxin , Tang Ting , Diao Yanbo , Li Mengyang , Yao Jun
Published: May 2018

With the development of large wind farms, the voltage problem caused by the power changes of wind farms occurs continuously because of the wind speed variation. The problem cannot be resolved by extra reactive power compensation because of the limitations in cooperation and response speed. A doubly fed induction generator (DFIG) possesses the power decoupling control capability, which can be used to prevent the voltage change rapidly. However, the dynamic processes of the power demands of the grid and the power limits of the DFIG have not been considered. Therefore, a vector equivalent model of the DFIG considering the controllability of the rotor voltage is established. The feasible power ranges that are limited by the electromagnetic process and controller response are deduced. The dynamic requirement and limitation of the reactive power under the wind speed variation are investigated. The emergency control strategy of reactive power contributed by the DFIG is proposed on the basis of the requirement and limitation. The simulation shows that the rapid adjustment capability of the DFIG can be fully utilised by the proposed method.
Performance of rank metric codes for interference constrained wireless sensor networks
Authors: Karim Yazbek Abdul , Sarr Ndéye Bineta , El‐Qachchach Imad , Cances Jean‐Pierre , Meghdadi Vahid , Boeglen Herve , Vauzelle Rodolphe
Published: May 2018

Future wireless communication systems will consist of multiple networks with various capabilities. Wireless networks may encounter severe distortions due to the presence of interfering signals generated at some power stations dedicated to smart grid applications. In fact, severe environmental effects of high voltage substations must be considered, particularly impulsive noise needs to be taken into account. Firstly, to cope with this kind of hostile environment, an efficient channel coding scheme in a mono‐user system is proposed, when one source user transmits data directly to one terminal user. Performance analysis shows that the proposed coding schemes based on rank metric codes are very efficient to eliminate impulsive noise in mono‐user mode. Furthermore, this approach are expanded in order to show the efficiency of rank codes in Wireless Sensors Networks (WSNs), when considering the problem of collecting data in WSNs in the presence of impulsive noise errors together with AWGN channel. To increase the reliability of the system, an advanced Network Coding technique (NC) is applied based on LRPC (Low Rank Parity Check) codes which exhibits noteworthy performances.
Toy model for the acceleration of blazar jets
Authors: Liodakis I.
Published: May 2018

Context. Understanding the acceleration mechanism of astrophysical jets has been a cumbersome endeavor from both the theoretical and observational perspective. Although several breakthroughs have been achieved in recent years, on all sides, we are still missing a comprehensive model for the acceleration of astrophysical jets.

Aims. In this work we attempt to construct a simple toy model that can account for several observational and theoretical results and allow us to probe different aspects of blazar jets usually inaccessible to observations.

Methods. We used the toy model and Lorentz factor estimates from the literature to constrain the black hole spin and external pressure gradient distributions of blazars.

Results. Our results show that (1) the model can reproduce the velocity, spin and external pressure gradient of the jet in M 87 inferred independently by observations; (2) blazars host highly spinning black holes with 99% of BL Lac objects and 80% of flat spectrum radio quasars having spins a > 0.6; (3) the dichotomy between BL Lac objects and flat spectrum radio quasars could be attributed to their respective accretion rates. Using the results of the proposed model, we estimated the spin and external pressure gradient for 75 blazars.
Dynamic 4D-CT Angiography for Guiding Transarterial Chemoembolization: Impact on the Reduction of Contrast Material, Operator Radiation Exposure, Catheter Consumption, and Diagnostic Confidence
Authors: Albrecht Moritz , Vogl Thomas , Wichmann Julian , Martin Simon , Scholtz Jan-Erik , Fischer Sebastian , Hammerstingl Renate , Harth Marc , Nour-Eldin Nour-Eldin , Thalhammer Axel , Zangos Stephan , Bauer Ralf
Published: May 2018

Purpose This study was carried out to investigate the impact of abdominal dynamic four-dimensional CT angiography (4D-CTA) for guiding transarterial chemoembolization (TACE) on the amount of contrast material used, operator radiation exposure, catheter consumption, and diagnostic confidence.

Materials and Methods Written consent was waived for this IRB-approved retrospective study. 29 patients (20 men; mean age: 65.7 ± 11.5 years) with malignant liver lesions underwent 4D-CTA, prior to initial TACE. Time-resolved volume-rendering technique (VRT), maximum-intensity projection (MIP), and multiplanar reconstruction (MPR) series were reconstructed, enabling a direct selective catheterization of the tumor-supplying artery without prior conventional digital subtraction angiography (DSA). 29 patients (16 men; mean age: 69.4 ± 13.9) who underwent traditional TACE served as the control group. The amount of administered contrast media, operator radiation exposure, and catheter consumption during TACE were compared. Two radiologists assessed diagnostic confidence in the exclusion of portal vein thrombosis.

Results 4D-CTA TACE resulted in a significant reduction in the amount of contrast media used, compared to traditional TACE (–61.0 ml/ –66.3 % intra-arterial, –12.8 ml/ –13.8 % overall; P < 0.001). The dose-area product indicating operator radiation exposure during intervention was reduced by 50.5 % (P < 0.001), and 0.7 fewer catheters on average were used (P = 0.063), while 4D-CTA data was available to guide TACE. Diagnostic confidence in the exclusion of portal vein thrombosis was significantly enhanced by 4D-CTA, compared to traditional DSA images (scores, 3.9 and 2.4, respectively; P < 0.001).

Conclusion Dynamic 4D-CTA enables TACE with a substantially reduced amount of contrast material, decreases operator radiation exposure, and increases diagnostic confidence in the exclusion of portal vein thrombosis.

Key points 

Citation Format
Leishmanicidal Effects of Piperlongumine (Piplartine) and Its Putative Metabolites
Authors: Moreira Fernanda , Riul Thalita , Moreira Marcela , Pilon Alan , Dias-Baruffi Marcelo , Araújo Márcio , Lopes Norberto , de Oliveira Anderson
Published: May 2018

Piperlongumine is an amide alkaloid found in Piperaceae species that shows a broad spectrum of biological properties, including antitumor and antiparasitic activities. Herein, the leishmanicidal effect of piperlongumine and its derivatives produced by a biomimetic model using metalloporphyrins was investigated. The results showed that IC50 values of piperlongumine in promastigote forms of Leishmania infantum and Leishmania amazonensis were 7.9 and 3.3 µM, respectively. The IC50 value of piperlongumine in the intracellular amastigote form of L. amazonensis was 0.4 µM, with a selectivity index of 25. The piperlongumine biomimetic derivatives, Ma and Mb, also showed leishmanicidal effects. We also carried out an in vitro metabolic degradation study showing that Ma is the most stable piperlongumine derivative in rat liver microsome incubations. The results presented here indicate that piperlongumine is a potential leishmanicidal candidate and support the biomimetic approach for development of new antileishmanial derivatives.
A Complementary Toolbox of Iterative Methods for the Stereo­selective Synthesis of Heteroatom-Rich Motives from C1-Building Blocks
Authors: Hirschhäuser Christoph , Kirupakaran Sujenth , Korth Hans-Gert
Published: May 2018

The ability to assemble organic molecules one carbon atom at a time has been a long-held dream for chemists. Modern boronate homologations with chiral carbenoids allow for the assembly-line synthesis of long chiral alkyl chains with excellent control over individual stereocenters. Nevertheless, heteroatom rich motives present a serious synthetic challenge to this approach. Interestingly, older methods based on substrate-controlled homologations of chiral boronic esters or umpolung of a carbonyl nucleophile can offer complementary solutions. A combination of these approaches might thus extend the range of possible targets currently within grasp of a C1-based synthesis. Link to video abstract: https://www.youtube.com/watch?v=PH_HBrqQwtg .

1 Introduction

2 Substrate Control: Stereoselective Addition of d1-Reagents to Aldehydes­

3 Stereocontrol by Chiral Auxiliary/Director: The Matteson Boronate Homologation

4 Reagent Control: Moving Chiral Information to the Carbenoid

5 Conclusions and Outlook
Total Synthesis of Bis-anthraquinone Antibiotic BE-43472B
Authors: Yamashita Yu , Hirano Yoichi , Takada Akiomi , Takikawa Hiroshi , Suzuki Keisuke
Published: May 2018

This is a full account of our synthetic endeavor on the total synthesis of bis-anthraquinone antibiotic BE-43472B, an unusual octacyclic aromatic polyketide with a bis-anthraquinone scaffold. Three key steps enabled a facile access to the anthraquinone unit corresponding to the ABCF rings; (1) cyclo-condensation or -addition of benzonitrile oxides with cyclic enone derivatives, (2) benzoin cyclization for the stereoselective ring fusion with an angular hydroxy group, and (3) pinacol rearrangement for stereoselective installation of the angular aryl group. Other keys for the success include, (4) diastereoselective methylation of a lactol derivative, and (5) late-stage installation of the C3 hydroxy group through stereoselective oxirane ring formation via halohydrin derivatives. Whereas oxidation of the double bond in the enone with an adjacent 1,3-diketone moiety failed, the projected oxidation was achieved with the alkene keeping the isoxazole moiety intact as a 1,3-diketone equivalent. In the racemic total synthesis, X-ray crystal structure analysis of the target was achieved, proving the three-dimensional architecture for the first time. The asymmetric total synthesis was also achieved by exploiting a cycloadduct of the nitrile oxide and the enantiomerically pure cyclohexenone, which was convertible to the common intermediate via dehydrogenation followed by alkoxycarbonylation.
Contrecoup Acute Epidural Hematoma—A Rare Case Report
Authors: Banga Manpreet , Sandeep B. , Dixit Sourabh , Saha Suniti
Published: May 2018

Epidural hematoma (EDH) is a traumatic accumulation of blood between the inner table of the skull and the dural membrane. Contact-related skull deformation causes inbending or fracturing of cranium or both, leading to separation of the dura mater from inner table. This injures the dural arteries, veins, venous sinus, or diploid channels, producing EDH. They usually occur as a result of direct impact injuries to the head, ipsilateral to impact side. Incidence of epidural hematoma is 1 to 3% of all head injuries. Contrecoup EDH cases are rare. and because of its rarity, we present a case report of a 17-year-old boy with contrecoup EDH who sustained head injury due to road traffic accident. Computed tomography of the brain showed left occipital bone fracture and large contrecoup extradural hematoma in right frontal region associated with pneumocephalus and hemorrhagic contusional edema beneath it. The EDH was operated on, and the patient was discharged uneventfully.
Home Care of Patients with Head Injury: Are We Neglecting the Caregivers?
Authors: Shoaib Yawar , Dagar Amit , Reyaz Abraq
Published: May 2018

In the absence of professional long-term care facilities in India, home care to patients with head injury is usually provided by family members. In this scenario, the mental health of the caregivers remains an important issue. This factor is constantly neglected by the health care providers and the society alike. With the result, the caregivers are prone to depression, anxiety, and other forms of mental illnesses. This also has a negative impact on the recovery and rehabilitation of the head injury survivor. In this article, the authors have reviewed relevant literature to find out the extent and prevalence of this problem among home caregivers of patients with head injury. The authors have also highlighted the possible measures that the treating neurosurgeon and the society can take for effective management of these issues. Their aim is to make the neurosurgeon and other health care providers aware of this issue and its various ramifications.
Endovascular Occlusion of Traumatic Carotid Cavernous Fistula by Using Detachable Balloon in Various Ways: A Case Series
Authors: Srivastava Trilochan , Husain Shakir , Gandhi Ashok , Sinha Virendra
Published: May 2018

Introduction The detachable balloons are not frequently used nowadays for endovascular occlusion of carotid-cavernous fistula (CCF) because of lack of availability and supposed high risk of recurrence. This study describes the various way of detachable balloon embolization for traumatic CCF.

Materials and Methods We have used endovascular detachable balloon to occlude the traumatic CCF under local anesthesia in various ways in 12 traumatic cases of CCF from March 2013 to April 2015. Clinical and computed tomographic (CT) angiography follow-up was done at 6 and 12 months.

Results Clinical follow-up from 6 to 12 month showed persistent resolution of symptoms in 10 cases; 2 cases had developed slight proptosis and chemosis. CT angiography done in nine cases after 6 to 9 months showed no residual filling in CCF.

Conclusion The detachable balloon either single or double with or without coils can be used in the management of CCF by different methods. Detachable balloon is a cheaper alternative compared with coiling. It is technically easier to perform and can be performed under local anesthesia.
Utility of Transcranial Doppler in Estimating Cerebral Perfusion Pressure in Traumatic Brain Injury: A Prospective Observational Trial
Authors: Ramanan Rajagopal , Joseph Mathew
Published: May 2018

Title Utility of transcranial Doppler (TCD) in estimating cerebral perfusion pressure (eCPP) in traumatic brain injury—a prospective observational trial.

Aim To validate the utility of a noninvasive technique of eCPP estimation using transcranial Doppler (TCD).

Materials and Methods Eighteen patients with severe traumatic brain injury (TBI) requiring intracranial pressure (ICP) monitoring as per the Brain Trauma Foundation guidelines were prospectively recruited for the study. ICP was measured in all patients using an intraventricular catheter. Mean arterial pressure (MAP) was recorded from an intra-arterial catheter. Cerebral perfusion pressure (CPP) was calculated as the difference between MAP and ICP. Middle cerebral blood flow velocities were recorded using TCD, and CPP was estimated from the middle cerebral artery (MCA) flow velocities (eCPP) using the formula eCPP = (MAP × end diastolic velocity [EDV]/mean velocity [MV]) + 14. Total 185 simultaneous readings of CPP and eCPP were available for analysis. Reliability statistics between CPP and eCPP were computed to calculate the intraclass correlation (ICC).

Results The average CPP measured using intraventricular catheter was 73.2 (+/−12.4), and the mean estimated eCPP was 76.7 (+/−10.9). We found a very good Pearson's correlation between CPP and eCPP (r = 0.743) with a Cronbach's α of 0.843. In 86.2% of examinations, the estimation error of measuring CPP was within 10 mm Hg, and in 93.1% examinations, it was within 15 mm Hg.

Conclusion eCPP estimated using TCD can serve as reliable noninvasive alternative in situations in which ICP monitoring is not available, even in moderate or mild head injury.
Large Retropharyngeal Abscess Associated with Cervical Spine Tuberculosis
Authors: Agrawal Amit , Santhi Vissa , Kumar Gali , Sandeep Yashwanth
Published: May 2018

The authors report a case of a 25-year-old man who presented with the history of neck pain and weakness of the right hand of 6-month duration. He had history of fever with evening rise in temperature, loss of weight, and cough. Radiologic investigations of the cervical spine showed collapse of the C5 vertebral body and partial destruction of the C4 and C6 vertebral bodies with kyphotic deformity and a large retropharyngeal hyperintense collection. The patient underwent drainage of the abscess, and the histopathology was suggestive of tuberculosis. He was started on antitubercular treatment and doing well at follow-up.
Anterior Cervical Corpectomy and the Operating Team: A Controversy?
Authors: Nikova Alexandrina , Birbilis Theodossios
Published: May 2018

Cervical myelopathy is multifactorial disease that can lead to many dysfunctions. Surgical treatment is believed to be the best healing choice. The authors searched the published data on Medline on this subject and found a difference between the neurosurgeons and orthopaedics on the topic of anterior corpectomy for cervical myelopathy. The difference between the orthopaedics and neurosurgeons is not big, but it could be relevant to the final outcome, which appears to be better in the neurosurgeons. The complication rate is also variable between the groups, with lower rates of complication reported by the neurosurgeons. Therefore, despite the fact that the postoperative outcome depends on many factors, such as preoperative condition, additional comorbidities, age, and lifestyle, this article also finds that the surgical team, after comparing basic techniques that the team used for anterior cervical corpectomy (ACC), is also responsible to some extent. This, however, is not a competition, and future cooperation between the teams might be beneficial for all.
Simultaneous Septal Perforation Repair with Septorhinoplasty: A 31-Year Experience
Authors: Delaney Sean , Kridel Russell
Published: May 2018

Septal perforation repair and septorhinoplasty (SRP) each present unique surgical challenges. However, in many instances, these procedures may be performed together successfully. In this study, the authors aim to determine the safety and effectiveness of combining primary or revision SRP and septal perforation repair via an open approach. A retrospective review was carried out of all consecutive patients who had SRP and septal perforation repair via an open approach between 1986 and 2017 in the senior author's practice. Perforation closure in surgery and at the patient's last follow-up, resolution of presenting symptoms, cosmetic results, and complications were analyzed. Records for 141 patients who had simultaneous septal perforation repair and SRP via an open approach, with a mean follow-up of 3.24 years, were reviewed. The mean anterior–posterior perforation dimension was 1.41 ± 0.89 cm, and the mean vertical perforation dimension was 1.16 ± 0.59 cm. The most common etiologies for septal perforation were previous SRP (35.4%) and septoplasty (24.1%). An overall 93.6%, perforation closure, 91.1% symptom relief, and 91.2% patient satisfaction with cosmetic results were achieved. Septal perforations under 1.5 cm in height were closed in 96.7% of patients as opposed to 71.4% of patients with perforations 1.5 cm or taller. Minor revision rhinoplasties were performed in 7.0% of patients. Postoperative infections were rare and noted in only two (1.4%) patients. In the largest study of its kind to date, the authors have shown that in experienced hands septal perforation repair may be performed simultaneously with primary or revision SRP via an open approach without compromising the perforation repair outcome. The vertical dimension of a septal perforation and presence of mucosa above and below a perforation are important considerations for the difficulty of a perforation closure, as septal mucosa is recruited from these locations in our technique of four-quadrant intranasal bipedicled mucosal advancement flap closure.
Ion velocity analysis of rotating structures in a magnetic linear plasma device
Authors: Claire N. , Escarguel A. , Rebont C. , Doveil F.
Published: May 2018

The MISTRAL device is designed to produce a linear magnetized plasma column. It has been used a few years ago to study a nonlinear low frequency instability exhibiting an azimuthal number m = 2. By changing the experimental configuration of MISTRAL, this work shows experimental results on an m = 1 rotating instability with strongly different behavior. The spatio-temporal evolution of the ion velocity distribution function given by a laser-induced fluorescence diagnostic is measured to infer the radial and azimuthal velocities, ion fluxes, and electric fields. The naive image of a plasma exhibiting a global rotation is again invalidated in this m = 1 mode but in a different way. Contrary to the m = 2 mode, the rotation frequency of the instability is lower than the ion cyclotron frequency and ions exhibit a complex behavior with a radial outward flux inside the unstable arm and azimuthal ion fluxes always directed toward the unstable arm. The azimuthal ion velocity is close to zero inside the ionization region, whereas the radial ion velocity grows linearly with radius. The radial electric field is oriented inward inside the unstable arm and outward outside. An axial velocity perturbation is also present, indicating that contrary to the m = 2 mode, the m = 1 mode is not a flute mode. These results cannot be easily interpreted with existing theories.
Thermal stress effects on the flexural wave bandgap of a two-dimensional locally resonant acoustic metamaterial
Authors: Li Zhen , Zhu Yun , Li Yueming
Published: May 2018

The elastic wave bandgap is obviously affected by heat while considering thermal stress. Nevertheless, the flat band, occurring in the lowest flexural branch, has not yet been explained clearly. This study investigates the influence of thermal stress on a flexural wave bandgap in a two-dimensional three-component acoustic metamaterial. Simulation results demonstrate that the band structure shifts to a lower frequency range, and the vibration response appears at a larger amplitude due to the bending stiffness being softened by the compressive membrane force. In addition, the first flexural band reduces to zero frequency in the central Brillouin zone. By viewing the vibration modes of the proposed unit cell, it is found that the out-of-plane mode shape attenuates with increasing temperature, while the in-plane vibration modes are unaffected by thermal stress.
Toward a comprehensive UV laser ablation modeling of multicomponent materials—A non-equilibrium investigation on titanium carbide
Authors: Ait Oumeziane Amina , Parisse Jean-Denis
Published: May 2018

Titanium carbide (TiC) coatings of great quality can be produced using nanosecond pulsed laser deposition (PLD). Because the deposition rate and the transfer of the target stoichiometry depend strongly on the laser-target/laser-plasma interaction as well as the composition of the laser induced plume, investigating the ruling fundamental mechanisms behind the material ablation and the plasma evolution in the background environment under PLD conditions is essential. This work, which extends previous investigations dedicated to the study of nanosecond laser ablation of pure target materials, is a first step toward a comprehensive non-equilibrium model of multicomponent ones. A laser-material interaction model coupled to a laser-plasma interaction one is presented. A UV 20 ns KrF (248 nm) laser pulse is considered. Ablation depths, plasma ignition thresholds, and shielding rates have been calculated for a wide range of laser beam fluences. A comparison of TiC behavior with pure titanium material under the same conditions is made. Plasma characteristics such as temperature and composition have been investigated. An overall correlation between the various results is presented.
Enhancement of emission of InGaN/GaN multiple-quantum-well nanorods by coupling to Au-nanoparticle plasmons
Authors: Xing Jieying , Chen Yinsong , Liu Yuebo , Liang Jiezhi , Chen Jie , Ren Yuan , Han Xiaobiao , Zhong Changming , Yang Hang , Huang Dejia , Hou Yaqian , Wu Zhisheng , Liu Yang , Zhang Baijun
Published: May 2018

We demonstrate the enhancement of emission of InGaN/GaN multiple-quantum-well nanorods by nearly a factor of 2 by coupling them to localized surface plasmons of Au nano-particles (NPs). The Au NPs are fabricated in situ on the nanorods using a Ni/SiO2/Au/SiNx compound functional layer. This layer serves as a combination dry-etch mask for fabricating the nanorods and the Au NPs, as well as providing isolation necessary to prevent fluorescence quenching. Time-resolved photoluminescence measurements confirm that emission enhancement originates from the coupling.
Atomic scale origins of sub-band gap optical absorption in gold-hyperdoped silicon
Authors: Ferdous Naheed , Ertekin Elif
Published: May 2018

Gold hyperdoped silicon exhibits room temperature sub band gap optical absorption, with potential applications as infrared absorbers/detectors and impurity band photovoltaics. We use first-principles density functional theory to establish the origins of the sub band gap response. Substitutional gold AuSi and substitutional dimers AuSi − AuSi are found to be the energetically preferred defect configurations, and AuSi gives rise to partially filled mid-gap defect bands well offset from the band edges. AuSi is predicted to offer substantial sub-band gap absorption, exceeding that measured in prior experiments by two orders of magnitude for similar Au concentration. This suggests that in experimentally realized systems, in addition to AuSi, the implanted gold is accommodated by the lattice in other ways, including other defect complexes and gold precipitates. We further identify that it is energetically favorable for isolated AuSi to form AuSi − AuSi, which by contrast do not exhibit mid-gap states. The formation of dimers and other complexes could serve as nuclei in the earliest stages of Au precipitation, which may be responsible for the observed rapid deactivation of sub-band gap response upon annealing.
The direct observation of ferromagnetic domain of single crystal CrSiTe3
Authors: Wu Shenghang , Wang Lihai , Gao Bin , Wang Yazhong , Oh Yoon Soek , Cheong Sang-Wook , Hong Jiawang , Wang Xueyun
Published: May 2018

Layered van der Waals interacting system that can be exfoliated to few layers are promising for exploring fundamental physics with rich electronic and optical properties. Combining the emerging phenomenon with long-range magnetic orders could lead to novel potential ultra-compact spintronics. Recently, CrXTe3 (X=Ge, Si) were reported that can persist magnetism after being exfoliated to few layers, however the magnetic domain structure in layered or bulk single crystal has remained unexplored. Here we choose CrSiTe3 single crystal as a model system, combining low-temperature magnetic force microscope, to demonstrate the magnetic domain structure, as well as the domain evolution in the presence of magnetic field, which is consistent with the magnetic behaviors measured by Magnetic Properties Measurement System (MPMS). Our result gives a simple portray of the magnetic properties of single crystal CrSiTe3, which provides a basis for the future research on magnetic layered van der Waals interacting system in potential application at 2-dimensional limit.
Coupled dielectric permittivity and magnetic susceptibility in the insulating antiferromagnet Ba2FeSbSe5
Authors: Maier S. , Moussa C. , Berthebaud D. , Gascoin F. , Maignan A.
Published: May 2018

We report on coupled changes in the dielectric permittivity and the magnetic susceptibility in the insulating antiferromagnet Ba2FeSbSe5. The real part of the dielectric permittivity (ε′) and the thermal conductivity (κ) shows pronounced anomalies at the Néel temperature (TN). Our findings show that there is a weak coupling between electric dipoles and magnetic spins, which is mediated by spin-lattice coupling possibly through exchange striction effects.
DAVIS: A direct algorithm for velocity-map imaging system
Authors: Harrison G. R. , Vaughan J. C. , Hidle B. , Laurent G. M.
Published: May 2018

In this work, we report a direct (non-iterative) algorithm to reconstruct the three-dimensional (3D) momentum-space picture of any charged particles collected with a velocity-map imaging system from the two-dimensional (2D) projected image captured by a position-sensitive detector. The method consists of fitting the measured image with the 2D projection of a model 3D velocity distribution defined by the physics of the light-matter interaction. The meaningful angle-correlated information is first extracted from the raw data by expanding the image with a complete set of Legendre polynomials. Both the particle’s angular and energy distributions are then directly retrieved from the expansion coefficients. The algorithm is simple, easy to implement, fast, and explicitly takes into account the pixelization effect in the measurement.
Kinetic instability of electrostatic ion cyclotron waves in inter-penetrating plasmas
Authors: Bashir M. F. , Ilie R. , Murtaza G.
Published: May 2018

The Electrostatic Ion Cyclotron (EIC) instability that includes the effect of wave-particle interaction is studied owing to the free energy source through the flowing velocity of the inter-penetrating plasmas. It is shown that the origin of this current-less instability is different from the classical current driven EIC instability. The threshold conditions applicable to a wide range of plasma parameters and the estimate of the growth rate are determined as a function of the normalized flowing velocity (u0/vtfe), the temperature (Tf/Ts) and the density ratios (nf0/ns0) of flowing component to static one. The EIC instability is driven by either flowing electrons or flowing ions, depending upon the different Doppler shifted frequency domains. It is found that the growth rate for electron-driven instability is higher than the ion-driven one. However, in both cases, the denser (hotter) is the flowing plasma, the lesser (greater) is the growth rate. The possible applications related to the terrestrial solar plasma environment are also discussed.