bluuebunny/crossref_metadata_2025 huggingface dataset:
Four LTE low‐band smartphone antennas and their MIMO performance with user's hand presence
Authors: Wong Kin‐Lu , Chen Yu‐Chen , Li Wei‐Yu
Published: June 2016

Owing to the narrow regions along the four edges of the modern smartphone, especially the two narrow regions along the long (side) edges thereof, it has been a design challenge to embed the internal antennas therein. The design challenge is especially critical for embedding the long‐term evolution (LTE) low‐band antennas with operating frequencies below 1 GHz. In this study, based on the open‐slot antenna structure, the design of four LTE low‐band antennas, respectively, disposed along the four edges of the smartphone are presented. The two antennas along the two short (top and bottom) edges have a low profile of 10 mm and can cover 698–960 MHz. The two antennas along the two long edges have a low profile of 1 mm only and can cover 824–960 MHz. The four antennas can be applied in a 4 × 4 multiple‐input multiple‐output (MIMO) system in the 824–960 MHz band (e.g., the LTE band 5 and 8). Conversely, the two short‐edge antennas can be used for 2 × 2 MIMO in the 698–960 MHz band (e.g., the LTE band 5, 8, 13, and 17). The operating principle and antenna performance of the four antennas are presented. The obtained channel capacities for 4 × 4 MIMO and 2 × 2 MIMO operations are also shown. Effects of the user's hand holding the smartphone with the four antennas therein are also analyzed. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2046–2052, 2016
A novel hybrid loaded vivaldi antenna with broadened relative bandwidth
Authors: Wu Dong‐Wei , Wang Xue‐Mei , Xie Yong‐Jun , Niu Li‐Qiang
Published: June 2016

A novel Vivaldi antenna hybrid loaded with patches, resistors, and the split‐ring resonator (SRR) structure has been presented in this letter, since the resistors and the SRR structure are deemed to be capable of extending the low‐end bandwidth limitation and improving the impedance characteristics at the lower frequency. As contrast, the hybrid loaded and resistor loaded Vivaldi antennas design are numerically and experimentally demonstrated, showing the benefits of the adopted structure in extending the relative bandwidth to 168.22% and 160.77%, reducing the low‐end operating frequency of 69.8% and 57.8%, respectively. Compared with traditional Vivaldi antennas, the hybrid loaded Vivaldi antenna indicates the feasibility of extending the relative working bandwidth and reducing the low‐end working frequency while maintaining preferable miniaturization characteristics. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2037–2041, 2016
A 2.4 GHz SiP radio module with embedded antenna and IPD matching and filter circuits
Authors: Hirvonen Mervi , Vähä‐Heikkilä Tauno , Yrjänä Samuli , Mäkelä Raimo , Järvinen Petri
Published: June 2016

In this article, a 2.4 GHz SiP radio module with embedded antenna suitable for various operation scenarios like in free space, on metal, and on body, is presented. The size of the whole module is 13.5 × 7.5 × 4.0 mm3. In addition to the antenna, the module includes matching and filter circuits implemented on IPD technology, as well as a radio transceiver. There are no ground plane or no ground plane opening limitations for the underlying electronics board increasing the usability and reliability of the SiP radio module. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2062–2064, 2016
A dual‐band metamaterial microwave absorber
Authors: Tak Jinpil , Jin Yunnan , Choi Jaehoon
Published: June 2016

A dual‐band metamaterial microwave absorber for X band (8–12 GHz) applications is proposed. A unit cell of the absorber consists of an electric LC (ELC) resonator, a backing ground plate, and an FR4‐epoxy substrate with 0.8 mm thickness. To realize efficient space utilization for the dual resonance, an ELC resonator consisting of asymmetric triangle split‐ring resonators is adopted. Using effective medium parameters extracted from the S‐parameters, the EM behavior is clarified to describe the operating mechanism. The miniaturized dimensions of the unit cell are 8 mm × 8 mm × 0.8 mm. The measured results exhibit two absorptivity peaks stronger than 98.5% and FWHMs of 8.4% and 7.25% at 8.2 GHz and 12 GHz, respectively. Additionally, high absorptivity performance is achieved for EM waves from 0° to 60° regardless of the incident angle. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2052–2057, 2016
Study of microstrip line‐fed flower‐shaped patch antenna providing enhanced bandwidth and radiation efficiency
Authors: Rani Patre Situ , Singh Surya P.
Published: June 2016

This article presents the simulation and experimental studies of a broadband flower‐shaped patch antenna with semi‐elliptical partial ground plane fed through tapered microstrip line. The conventional circular patch is reshaped to obtain the proposed broadband flower‐shaped patch, which has distinct smaller segments and larger perimeter without changing the (largest) patch radius. The effect of different configurations of feed line and ground plane on the impedance bandwidth of the antenna is studied through simulation using Ansys' High Frequency Structure Simulator (HFSS) software. The simulated and measured bandwidths of the proposed antenna with optimum configurations of feed line and ground plane for input VSWR ≤ 2 are found to be 142% (2.3–13.6 GHz) and 135.88% (2.1–11.0 GHz), respectively. The radiation patterns of the antenna are bidirectional and omni‐directional in E‐ and H‐plane respectively. The proposed antenna has high radiation efficiency of more than 80% and reasonable gain over whole operating frequency band. Further, the input and radiation characteristics of the proposed antenna are compared with the respective characteristics of identical antenna excited using coplanar waveguide (CPW) feed. The bandwidth improvement of proposed antenna compared to reference one is explained using leaky wave concept. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2041–2046, 2016
High sensitive microwave sensor based on symmetrical split ring resonator for material characterization
Authors: Alahnomi Rammah A. , Zakaria Z. , Ruslan E. , Mohd Bahar. Amyrul Azuan , Ab Rashid S. R.
Published: June 2016

A simple novel microwave planar sensor based on symmetrical split ring resonator (SSRR) has been applied for the first time to measure the dielectric permittivity of materials under test (MUT). The results achieve narrow resonance with high Q sensitivity of 407 which makes it great promising applications for biosensors in the future. Three practical materials have been used as standards to validate the sensor. A detailed sample thickness analysis has been considered and accordingly the mathematical equation is driven to extract the properties of materials. Experimentally, the measured and theoretical results are found in an excellent agreement with a 2–3% possibility of typical error in the permittivity measurement. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2106–2110, 2016
Statistical variation of wire parameters within complex aerospace networks
Authors: Lundquist Eric J. , Furse Cynthia
Published: June 2016

This work evaluates the variation of wire impedance and velocity of propagation in bundled wires. Unshielded wire bundling was found to cause changes greater than 60Ω with standard deviation between 30.4–33.4Ω on 150Ω wires. Velocity of propagation was found to vary from 0.589c to 0.602c with a standard deviation of 0.0031c. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2082–2084, 2016
New topology of wide band EDFA using split band double pass amplification
Authors: Bouzid Belloui , Abu Khadra Fawwaz
Published: June 2016

A novel design of high and broad gain that covers C and L bands is demonstrated experimentally. The techniques, used in this paper, combine two double pass with split band structure. The signals travel in separate paths after being splitted using a coupler band splitter. The topology of this new configuration uses this technique to broaden the gain at its maximum range of amplification. The presented paper is to study the performance of the augmented gain of the EDFA configuration using what it can be called double pass wide band amplification. The results show a broadening range of 80 nm between 1520 nm and 1600 nm in the C and L band and high gain of 45 dB for the range 1525 nm and 1580 nm and lower gain for the range 1580 nm and 1600 nm. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2093–2096, 2016
Characterization of a dual‐wavelength erbium‐doped fiber laser with overlapping cavity incorporating chirped fiber bragg grating as whole reflecting mirror
Authors: Boroon Mohammad , Seyedzadeh Saleh , Moghaddasi Majid , Hitam Salasiah
Published: June 2016

A new and simple dual‐wavelength erbium doped fiber laser (EDFL) in long band is proposed and experimentally demonstrated. Chirped fiber Bragg gratings (CFBGs) as optical reflecting mirror‐are deployed with 10 nm nominal wavelength spacing. The combined signal of two reflections initialize lasing process. Dual wavelength lasing at room temperature is achieved at input power of 40 mW. Signal reaches to maximum value of 6.40 dBm at pump power of 80 mW where the signal diversity is 1.21 dB. The output of dual‐wavelength laser in linear overlapping cavity configuration appears in unpolarized low noise figure. Relatively large side mode suppression ratio (SMSR) of 41.88 dB is obtained. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2143–2146, 2016
Improvement the design of microwave dual‐band BPF by DGS technique
Authors: Amiri Shervin , Khajavi Mahboubeh
Published: June 2016

This article presents a new method for designing a dual‐band bandpass filter at microwave frequency with improvement on filter characteristics like bandwidth, in band insertion loss and outband and decrease the neutral harmonics on stopband with using defected ground structure (DGS) technique. The basic resonator, with a single passband, was designed using an open‐circuit capacitor‐coupled stripline resonator. An I‐shape architecture was employed at the middle part of the basic resonator to create a dual‐passband frequency response. Finally, the current density of the filter with DGS and without DGS is shown. Simulation results for the proposed filter include performance at 4.6 GHz and 7.3 GHz with respective bandwidths of 178 MHz and 155 MHz. Simulation results well match the characteristics of the fabricated filter. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2133–2137, 2016
Design of a patch antenna for ultra wide band applications
Authors: Hossain M. J. , Faruque M. R. I. , Islam M. T.
Published: June 2016

A new monopole microstrip patch antenna design for ultra‐wideband applications are proposed in this paper. The proposed antenna is comprised of a ring‐shaped with additional slot and upper cutting edge, a 50‐ohm microstrip line‐fed and a slotted limited ground plane. The proposed antenna size is 3.5 cm × 2.4 cm × 0.16 cm and is energized by microstrip feed line. The finite‐difference time‐domain method based Computer Simulation Technology (CST) and finite element method based High Frequency Structural Simulator (HFSS) is adopted in this investigation. The proposed antenna has been achieved excellent gain and the calculated bandwidth of the monopole antenna cover whole UWB frequency range. However, the measured results demonstrate that stable omnidirectional radiation pattern within the entire frequency band. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2152–2156, 2016
A 40 GHz‐100 GBPS wireless access network system based on all optical transformation and photoelectric direct detection
Authors: Li Guang , Liu Hongzhan
Published: June 2016

A 40 GHz coordinated multi‐point radio over fiber (40 GHz ‐CoMP‐ROF) transmission system based on 16‐quadrature amplitude modulation (QAM) and optical orthogonal frequency division multiplexing (OOFDM) and 2 × 2 multiple input multiple output (16QAM‐OOFDM‐2x2MIMO) and photoelectric direct detection is proposed and proved by theoretical derivation. Duo to the QAM and OOFDM and multiple input multiple output (MIMO) and optical orthogonal polarization splitting combining (OOPSC) and excellent algorithm, the rate of the wireless access system is up to 100Gpbs. The designed system is simulated and tested by OptiSystem which is a set of professional simulation software for communication. And then, electrical spectrum, optical spectrum, constellation diagram, clear eye diagram and good bit error rate (BER) of the wired downlink signal and the wireless downlink signal are obtained respectively. Because of the photoelectric direct detection, the complexity of the base station (BS) is simplified. Thanks to the all optical transformation and photonic multiple doubling frequency technique, the cost of the local oscillator with ultra‐high frequency is greatly reduced at the BS. Owing to the coordinated multi‐point (CoMP) technique, ultra‐high speed wireless transmitting between the mobile station and the BS can become a reality on the edge of the cell. Compared with recent schemes, the outlays of center station and base‐station are greatly decreased. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2194–2202, 2016
Improvement of isolation and envelop correlation coefficient using C‐loaded λ/4 loop antenna on hollow ground
Authors: Lee Jae‐Gon , Kim Dong‐Jin , Lee Jeong‐Hae
Published: June 2016

A C‐loaded λ/4 loop antenna on a hollow ground is presented to improve the isolation and envelop correlation coefficient (ECC) in the mobile terminals. The designed antenna is composed of a straight type of C‐loaded λ/4 loop on hollow ground and a monopole branch operating for LTE800 and LTE1900 bands, respectively. The proper value of a loaded capacitor of the loop makes λ/4 resonance, resulting in the parallel current flow on the ground plane while a conventional planar inverted‐F antenna (PIFA) generates a vertical current flow in the ground. Thus, the combination of two antennas will give rise to high isolation and low ECC. The isolation and ECC of both cases of PIFA (primary) versus PIFA (secondary) and PIFA (primary) versus C‐loaded λ/4 loop antenna with a monopole branch (secondary) are compared when they are diagonally placed in a mobile handset. The isolations in the former and latter cases are measured to be lower than −5.3 and −22 dB in the LTE800 band, respectively. Also, the ECC values in the former and latter cases are measured to be 0.81 and 0.29 from far‐field radiation patterns in the LTE800 band, respectively. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2189–2194, 2016
Dual circularly polarized falcate‐shaped slot antenna
Authors: Lee Sungwoo , Min Lee Jong , Yun Juho , Heon Kwon Oh , Jun Lim Hong , Bin Park Won , Cheol Hwang Keum
Published: June 2016

In this paper, the design of a low‐profile slot antenna with dual microstrip feeds is presented for broadband dual circular polarization. The proposed antenna is composed of a falcate‐shaped slot to achieve broadband circularly polarized radiation and two individual 50‐Ω microstrip feeds to realize both right‐ and left‐hand circular polarizations simultaneously at the same frequency. The overall dimensions of the fabricated antenna are 50 * 50 * 0.76 mm3. The measured −10 dB reflection bandwidths at port 1 and port 2 are 31.14% (5.64–7.72 GHz) and 30.05% (5.6–7.58 GHz), respectively. Furthermore, a port coupling level of less than −15.68 dB was also achieved across the operation band. The fabricated antenna also exhibits 3 dB axial ratio bandwidths of 56.47% (4.6–8.22 GHz) and 54.06% (4.63–8.06 GHz) for right‐ and left‐hand circular polarizations, respectively. The measured peak gains are higher than 3.66 dBic for both polarizations. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2245–2250, 2016
An improved broadband transition between microstrip and empty substrate integrated waveguide
Authors: Peng Hao , Xia Xinlin , Dong Jun , Yang Tao
Published: June 2016

In this letter, an improved broadband transition between microstrip and empty substrate integrated waveguide (ESIW) is proposed. The transition structure consists of a gradient microstrip line, a taper extended into ESIW, and ESIW section. Compared with the previous studies, the gradient microstrip line is introduced to expand the operating bandwidth and get a better performance, especially for the thinner dielectric substrate. The simulated and measured results have a good agreement. A back‐to‐back transition is designed, manufactured, and tested. For a single transition, the return loss and insertion loss are better than 13.5 and 0.75 dB from 6.6 to 16.45 GHz (85.5%), respectively. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2227–2231, 2016
Frequency reconfigurable E‐shaped patch antenna for medical applications
Authors: Kumar Jayendra , Talukdar F. A. , Basu Banani
Published: June 2016

Article proposes reconfigurable E‐shaped patch antenna using PIN diode to switch the antenna between two frequency states: 335–565 MHz, 1.29–1.42 GHz and 2.03–2.28 GHz in multiband and 300–645 MHz in single band. Placement of the rectangular slots operates the patch in multiband. Single band is achieved using a bandpass filter. Parasitic element improves the impedance characteristics. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2214–2217, 2016
Wide‐band frequency agile MIMO antenna system with wide tunability range
Authors: Hussain Rifaqat , Sharawi Mohammad S.
Published: June 2016

In this work, a 4‐element wide band frequency agile multiple‐input‐multiple‐output (MIMO) antenna system is presented. Frequency agility is achieved by loading the antenna elements with capacitive reactance using varactor diodes. The proposed MIMO antenna is a wide band antenna with very wide tunability range between 1610 and 2710 MHz, thus covering several well‐known wireless standards. Each tuned band has at least 470 MHz bandwidth. The proposed design is simple in structure with low profile antenna elements. The design is fabricated on an FR4 substrate with single element dimensions of 7.9 × 26.9 mm2 on a single board of dimensions 60 × 100 × 0.8 mm3. The proposed MIMO antenna system is highly suitable to be used in wireless handheld devices and mobile terminals within a cognitive radio platform. The antenna system is also characterized for MIMO performance metrics. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2276–2280, 2016
A 2.4‐GHz CMOS power amplifier using a gain and stability enhancement technique for IEEE 802.11N WLAN applications
Authors: Lee Changhyun , Park Changkun
Published: June 2016

In this work, we propose a gain and stability enhancement technique with compact size for RF CMOS linear power amplifier applications. The proposed amplifier is designed with differential and cascode structures. To realize a compact size of the power amplifier, the driver stage is merged into the power stage of the power amplifier. To minimize the number of essentially required inductors, the load impedance of the power stage is shared with the driver stage of the power amplifier. Additionally, to moderate stability problems in the power amplifier, the closed loop is removed using a common‐gate transistor, which operates in the saturation region. The power amplifier can then operate in the linear operation. To prove the feasibility of the proposed linear amplifier, we designed a 2.4 GHz CMOS power amplifier using the 180‐nm RF CMOS process. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2265–2268, 2016
C‐band high power and high efficiency harmonic‐tuned oscillator
Authors: Yi Yearin , Jeong Jinho
Published: June 2016

In this paper, a high efficiency power oscillator is designed at C‐band for the applications of wireless power transmission. A harmonic‐tuning technique is adopted to achieve a high efficiency at a high frequency. It is also shown that the efficiency of the oscillator is degraded due to the reduced gain of the semi‐conductor transistor at high frequency. The fabricated oscillator using GaN transistor shows an output power of 38.1 dBm with an efficiency of 58.4% at 5.71 GHz, which corresponds to the excellent performance among the reported oscillators around 5 GHz. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2281–2285, 2016
Novel Col12A1 variant expands the clinical picture of congenital myopathies with extracellular matrix defects
Authors: Punetha Jaya , Kesari Akanchha , Hoffman Eric P. , Gos Monika , Kamińska Anna , Kostera‐Pruszczyk Anna , Hausmanowa‐Petrusewicz Irena , Hu Ying , Zou Yaqun , Bönnemann Carsten G. , JȨdrzejowska Maria
Published: June 2016

Introduction

Mutations in the COL12A1 (collagen, type XII, alpha 1) gene have been described in a milder Bethlem‐like myopathy in 6 patients from 3 families (dominant missense), and in a severe congenital form with failure to attain ambulation in 2 patients in a single pedigree (recessive loss‐of‐function).

Methods

We describe an 8‐year‐old girl of Polish origin who presented with profound hypotonia and joint hyperlaxity at birth after a pregnancy complicated by oligohydramnios and intrauterine growth retardation.

Results

We identified a novel, potentially pathogenic heterozygous missense COL12A1 c.8329G>C (p.Gly2777Arg) variant using a targeted sequencing panel. Patient fibroblast studies confirmed intracellular retention of the COL12A1 protein, consistent with a dominant‐negative mutation.

Conclusions

As our patient showed a more intermediate phenotype, this case expands the phenotypic spectrum for COL12A1 disorders. So far, COL12A1 disorders seem to cover much of the severity range of an Ehlers‐Danlos/Bethlem‐like myopathy overlap syndrome associated with both connective tissue abnormalities and muscle weakness. Muscle Nerve 55: 277–281, 2017
Uroflowmetry in healthy women: A systematic review
Authors: Sorel Marique R. , Reitsma Hans J.B. , Rosier Peter F.W.M. , Bosch Ruud J.L.H.R. , de Kort Laetitia M.O.
Published: June 2016

Background

Although uroflowmetry is a widely used diagnostic test, reference values of uroflowmetry parameters in women are lacking making it difficult to interpret the test results.

Aim

To quantify the range of results in uroflowmetry parameters in healthy women based on a systematic review.

Methods

A search was made in the International Continence Society standardization articles, PubMed, Embase and the Cochrane Library (from inception to 27 February 2014). Studies on uroflowmetry in healthy women were included. The selected articles were examined using a critical appraisal process based on the QUADAS‐2 tool and the Critical Appraisal Skills Program.

Results

Mean values of uroflowmetry parameters in healthy women (mean age 37.1 years) were: voided volume (VV) 338 ml (SD 161), maximum flow rate (Qmax) 23.5 ml/s (SD 10), average flow rate (Qave) 13 ml/s (SD 6), postvoid residual (PVR) 15.5 ml (SD 25), voiding time (VT) 29 sec (SD 17), and time to maximum flow rate (time to Qmax) 8 sec (SD 6). Qmax was dependent on VV. There was no clear relationship between Qmax and age, and no correlation between parity and Qmax. A normal shape of the uroflowmetry curve was seen in 70–80% of the flows.

Conclusion

This systematic review provides an overview of the range of results of uroflowmetry parameters in healthy women. Neurourol. Urodynam. 36:953–959, 2017. © 2016 Wiley Periodicals, Inc.
Remeshing strategies for large deformation problems with frictional contact and nearly incompressible materials
Authors: Zhang Ziyu , Dolbow John E.
Published: June 2016

We present a framework to efficiently solve large deformation contact problems with nearly incompressible materials by implementing adaptive remeshing. Specifically, nodally integrated elements are employed to avoid mesh locking when linear triangular or tetrahedral elements are used to facilitate mesh re‐generation. Solution variables in the bulk and on contact surfaces are transferred between meshes such that accuracy is maintained and re‐equilibration on the new mesh is possible. In particular, the displacement transfer in the bulk is accomplished through a constrained least squares problem based on nodal integration, while the transfer of contact tractions relies on parallel transport. Finally, a residual‐based error indicator is chosen to drive adaptive mesh refinement. The proposed strategies are applicable to both two‐dimensional or three‐dimensional analysis and are demonstrated to be robust by a number of numerical examples. Copyright © 2016 John Wiley & Sons, Ltd.
Greater early and mid‐pregnancy gestational weight gains are associated with excess adiposity in mid‐childhood
Authors: Hivert Marie‐France , Rifas‐Shiman Sheryl L. , Gillman Matthew W. , Oken Emily
Published: June 2016

Objective

It is unclear how specific periods of gestational weight gain (GWG) during pregnancy relate to childhood adiposity. The goal of this study was to assess the differential impact of GWG timing on childhood body composition.

Methods

In 979 mother–child pairs from the pre‐birth Project Viva cohort, trimester‐specific GWG was calculated using clinically recorded weights. Outcomes included body mass index (BMI) z‐score, dual X‐ray absorptiometry fat mass index (kg/m2), and fat‐free mass index (kg/m2) in mid‐childhood. Linear regression models were used to assess associations of each trimester's GWG (per 0.2 kg/week) with childhood outcomes, adjusted for maternal prepregnancy BMI, sociodemographic variables, lifestyle, and GWG in prior trimester(s).

Results

Mean (SD) first trimester GWG was 0.22 (0.22) kg/week, second trimester 0.49 (0.18) kg/week, and third trimester 0.47 (0.20) kg/week. Faster first trimester GWG was associated with higher BMI z‐score (0.06 units [95% CI: 0.01–0.12] per 0.2 kg/week) and with higher adiposity according to all indices; associations were strongest in women with prepregnancy BMI >30 kg/m2. Faster second trimester GWG was associated with higher BMI z‐score (0.11 [0.04–0.18]), fat mass (fat mass index = 0.16 [0.02–0.31] kg/m2), and lean mass (fat‐free mass index = 0.11 [0.01–0.22] kg/m2). Third trimester GWG was not associated with childhood adiposity.

Conclusions

These results reinforce the importance of addressing appropriate GWG in early pregnancy.
Sarcolipin knockout mice fed a high‐fat diet exhibit altered indices of adipose tissue inflammation and remodeling
Authors: MacPherson Rebecca E.K. , Gamu Daniel , Frendo‐Cumbo Scott , Castellani Laura , Kwon Frenk , Tupling A. Russell , Wright David C.
Published: June 2016

Objective

To investigate indices of adipose tissue inflammation and remodeling in high‐fat diet (HFD) sarcolipin‐knockout (SLN−/−) mice. SLN regulates muscle‐based nonshivering thermogenesis and is up‐regulated with HFD. SLN−/− mice develop greater diet‐induced obesity and glucose intolerance. This is accompanied by increases in circulating catecholamines and fatty acids. Catecholamines and fatty acids play a role in the pathology of adipose tissue inflammation.

Methods

Male mice (wild type and SLN−/−) were fed a HFD (42% kcal from fat) for 8 weeks.

Results

SLN−/− mice displayed greater obesity and glucose intolerance. This was accompanied by higher circulating epinephrine and nonesterified fatty acids. Epididymal but not inguinal subcutaneous adipose tissue from SLN−/− mice displayed higher interleukin‐6, suppressor of cytokine signaling 3, interleukin‐1β, and tumor necrosis factor‐α mRNA expression, and this was associated with increased markers of macrophage infiltration (F4/80 expression and crown‐like structures) and M1 polarization (higher CD11c expression and CD11c/MGL1). Interestingly, this occurred despite SLN−/− mice having smaller adipocytes.

Conclusions

In conditions of nutrient excess, SLN−/− mice display depot‐specific increases in indices of adipose tissue inflammation and remodeling. This could be a compensatory response to reductions in muscle‐based thermogenesis.
Proteomics analyses of subcutaneous adipocytes reveal novel abnormalities in human insulin resistance
Authors: Xie Xitao , Yi Zhengping , Sinha Sandeep , Madan Meenu , Bowen Benjamin P. , Langlais Paul , Ma Danjun , Mandarino Lawrence , Meyer Christian
Published: June 2016

Objective

To provide a more global view of adipocyte changes in human insulin resistance by proteomics analyses.

Methods

Baseline biopsies of abdominal subcutaneous adipose tissue were obtained from 23 subjects without diabetes. Euglycemic clamps were used to divide subjects into an insulin‐resistant group (IR, N = 10) and an insulin‐sensitive (IS, N = 13) group, which were of similar age and gender but unequal adiposity (greater in IR). Proteins of isolated adipocytes were quantified by mass spectrometry using normalized spectral abundance factors.

Results

Of 1,245 proteins assigned, 30 were detected in at least 12 of the 23 subjects that differed significantly in abundance ≥1.5‐fold between IR and IS. IR displayed a pattern of increased cytoskeletal proteins and decreased mitochondrial proteins and FABP4 and FABP5. In subgroup analyses of adiposity‐matched subjects, several of these changes were less pronounced in IR, but the abundance of proteins related to lipid metabolism and the unfolded/misfolded protein response were significantly and unfavorably altered.

Conclusions

These results confirm lower abundance of mitochondrial proteins and suggest increased cytoskeletal proteins and decreased FABP4 and FABP5 in subcutaneous adipocytes of typical IR individuals. Changes in proteins related to lipid metabolism and the unfolded/misfolded protein may discriminate IR and IS individuals of equal adiposity.
Non‐tumour bone marrow lymphocytes correlate with improved overall survival in childhood acute lymphoblastic leukaemia
Authors: Edwin Claire , Dean Joanne , Bonnett Laura , Phillips Kate , Keenan Russell
Published: June 2016

Composition of tumour immune cell infiltrates correlates with response to treatment and overall survival (OS) in several cancer settings. We retrospectively examined immune cells present in diagnostic bone marrow aspirates from paediatric patients with B‐cell acute lymphoblastic leukaemia. Our analysis identified a sub‐group (∼30% of patients) with >2.37% CD20 and >6.05% CD7 expression, which had 100% OS, and a sub‐group (∼30% of patients) with ≤2.37% CD20 and ≤6.05% CD7 expression at increased risk of treatment failure (66.7% OS, P < 0.05). Immune cell infiltrate at diagnosis may predict treatment response and could provide a means to enhance immediate treatment risk stratification.
Hydrogels based on schiff base formation between an amino‐containing polyphosphazene and aldehyde functionalized‐dextrans
Authors: Morozowich Nicole L. , Nichol Jessica L. , Allcock Harry R.
Published: June 2016

Hydrogels generated by the interaction of two different water‐soluble polymers offer access to a new group of soft materials. A prototype amino‐functionalized polyphosphazene with both tyramine and ferulic acid‐based side groups was coupled to aldehyde functionalized‐dextrans to form hydrogels crosslinked via Schiff base chemistry. Synthesis of the polyphosphazene was accomplished by macromolecular substitution and protection‐deprotection chemistry, with characterization by 1H NMR, 31P NMR, solid state 13C NMR, and DSC techniques. Combination of the aqueous polyphosphazene and aldehyde functionalized‐dextran solutions at room temperature caused gelation with different gelation times and crosslink densities dependent on the aldehyde content of the dextran. The hydrogel properties were evaluated using rheology, thermal characterization, and cryo‐microscopy. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 2984–2991
Automatic code generation for quantum chemistry applications
Authors: Mazur Grzegorz , Makowski Marcin , Łazarski Roman , Włodarczyk Radosław , Czajkowska Ewa , Glanowski Michał
Published: June 2016

A unified, computer algebra system‐based scheme of code‐generation for computational quantum‐chemistry programs is presented. Generation of electron‐repulsion integrals and their derivatives as well as exchange‐correlation potential and its derivatives is discussed. Application to general‐purpose computing on graphics processing units is considered.
Modulation of β‐Hairpin Peptide Self‐Assembly: A Twenty‐Residue Poly‐l β‐Hairpin Modified Rationally as a Mixed‐l,d Hydrolase
Authors: Goyal Bhupesh , Srivastava Kinshuk Raj , Patel Kirti , Durani Susheel
Published: June 2016

The building blocks of protein structure are defined stereochemically and have remained frozen to only poly‐l alphabet. The D‐enantiomer can be explored to diversify shapes of proteins stereochemically and diversity in shape may enhance proteins in the scope of functional design. Illustrating the scope, we describe here design of a hydrolase mimic over twenty L‐ and D‐α‐amino‐acid residues. The design is accomplished by mutating canonical poly‐L β‐hairpin in a pair of cross‐strand residues to D‐stereochemical structure to provide a bend to β‐hairpin structure that allows its elaboration as a monomer freely soluble in water. The aromatic residues were suitably positioned in the designed mimic to stabilize the molecular fold and to bind aromatic substrate using π–π interaction. The catalytic triad residues were positioned in close proximity for hydrolysis of aromatic‐anchored ligand. The designed peptide variants are proven to bind p‐nitrophenyl phosphate using fluorescence studies and hydrolyze p‐nitrophenyl acetate using UV–based enzyme kinetic assays. The study thus highlights the role of stereochemistry in design of novel folds with desired function.
A General Synthesis Strategy for Highly Dispersed Amorphous MoO3 over Supported Catalysts
Authors: Dai Zhichao , Xu Shengqiang , Guo Lijuan , Huang Qingming , Hu Hui , Chen Xiaohui
Published: June 2016

Amorphous MoO3 was evenly deposited on a Bi2SiO5/SiO2 support by a strategy of heterogenous coprecipitation using Ti as structural promoter. The structure and properties of MoO3‐Bi2SiO5/SiO2 have been characterized by a series of techniques, including N2 adsorption/desorption analysis, X‐ray diffraction (XRD), transmission electron microscopy (TEM), X‐ray photoelectron spectroscopy (XPS) and ultraviolet‐visible light (UV‐vis) diffuse reflectance spectra (DRS).The addition of n‐butyl alcohol into synthesis medium resulted in the most dispersive amorphous MoO3, with an average particle size of 4 nm. Selective oxidation of propylene was chosen as a probe reaction to test the performance of catalysts. Kinetic study revealed that the method of heterogeneous coprecipitation enhanced catalytic performance via increasing the number of active sites, rather than changing the nature of it. This is well compatible with characterization results.
Copper Complex of Pinene based Schiff base [CuSBADBH]2: Synthesis and its Application in Catalytic Asymmetric Nitroaldol (Henry) Reaction
Authors: Boobalan Ramalingam , Chang You‐Ming , Chen Chinpiao , Lee Gene‐Hsian
Published: June 2016

Eight new pinene based tridentate Schiff bases of (+)‐(1S,2R,3S,5S)‐3‐amino‐6,6‐dimethylbicyclo[3.1.1]heptan‐2‐ol were synthesized from (+)‐(α)‐pinene. Copper complexes of these Schiff bases were prepared for asymmetric nitroaldol (Henry) reaction. Among the eight copper complexes, 3‐methylsalicylaldehyde‐derived [CuSBADBH‐4]2 32 showed high chiral induction (85 % ee) for the catalytic asymmetric Henry reaction of 4‐nitrobenzaldehyde. Under optimal reaction conditions, 1 mol% [CuSBADBH‐4]2 32 catalyzed enantioselective Henry reaction of various aromatic and poly aromatic aldehydes afforded the corresponding (R)‐β‐hydroxy nitroalkanes with high ee (up to 92 %) and yield (up to 99 %).
Tuning Size and Reducibility of Copper Oxide Particles Supported on SBA‐15
Authors: Koch Gregor , Schmack Lena , Ressler Thorsten
Published: June 2016

Copper citrate was deposited on SBA‐15 at various loadings ranging from 10.9 to 27.1 wt.%. Thermal decomposition resulted in copper oxide particles supported on SBA‐15. In order to study the effect of varying calcination conditions on the resulting particles, precursors were calcined both in a thin powder layer and in a thick powder layer. SBA‐15 and copper oxide particles were characterized using N2 physisorption, XRD, DR‐UV/Vis spectroscopy, and TEM. Depending on layer thickness during calcination, copper oxide particles of various sizes were observed in samples with the same chemical composition. Copper oxide particles were examined by temperature‐programmed reduction. Amorphous copper oxide particles showed a single H2 consumption peak and were reduced to copper at 240 °C. Larger crystalline copper oxide particles showed H2 consumption peaks with a shoulder at higher temperatures and were reduced to copper at 300 °C.
Linear and Cyclic Carbohydrate Receptors Based on Peptides Modified with Boronic Acids
Authors: Otremba Tobias , Ravoo Bart Jan
Published: June 2016

In this article we report the synthesis of boronic acid functionalized fluorenylmethoxycarbonyl (Fmoc) protected amino acids and their use in solid phase peptide synthesis to synthesize tripeptides with the motif Cys‐X–Cys (X=boronic acid functionalized amino acid). The interaction of these peptides with a set of carbohydrates in aqueous solution was studied by using a competitive indicator displacement assay as well as by isothermal titration calorimetry. We determined carbohydrate binding constants ranging from 2 x 101 M−1 up to 3 x 103 M−1 from these measurements. Moreover, the formation of cyclic hexapeptides was accomplished by oxidation of the thiols of the Cys to disulfides and the interactions between these cyclic receptors and carbohydrates were studied by using a competitive indicator displacement assay and isothermal titration calorimetry. The binding constants observed for these cyclic receptors are similar to the linear receptors.
Structural and Spectroscopic Properties of New Chiral Quinoline‐based Ln(III) Complexes
Authors: Mihorianu Monica , Leonzio Marco , Monari Magda , Ravotto Luca , Ceroni Paola , Bettinelli Marco , Piccinelli Fabio
Published: June 2016

The synthesis, the structural characterization and the luminescence spectroscopy of new Ln(III) nitrate complexes (Ln = La, Eu, Gd, Tb and Lu) with the quinoline‐based N, N’‐bis(2‐quinolylmethylidene)‐ 1,2‐(R,R+S,S)‐cyclohexanediamine, L1 and N, N’‐bis(2‐quinolylmethyl)‐ 1,2‐(R,R+S,S)‐cyclohexanediamine, L2 are presented. All the L1Ln(NO3)3 complexes and L2Ln(NO3)3 with Ln= La, Eu and Tb are isostructural. Metal ions such as La(III), Gd(III) and Lu(III) are able to promote intra‐ligand (IL) fluorescence from L1 and L2. Gd(III) and Lu(III) in addition, are also able to stimulate IL phosphorescence at room temperature from the L2 ligand, by means of “paramagnetic effect” and/or “heavy‐atom effect”. Both ligands are able to sensitize the typical f‐f Eu(III) luminescence and only L2 the one of Tb(III) (green emission). The Eu(III) emission features for both complexes [L1Eu(NO3)3 and L2Eu(NO3)3] are in agreement with their structural properties. All the complexes under investigation reveal promising application in the field of luminescent devices and biomedicine. In particular, excitation at 360 nm, in the case of L1‐based complexes, enable the use of glass optics and minimize interfering excitation by chromophores in biological media.
Growth of InAs Quantum Dots on GaAs (511)A Substrates: The Competition between Thermal Dynamics and Kinetics
Authors: Wen Lei , Gao Fangliang , Zhang Shuguang , Li Guoqiang
Published: June 2016

The growth process of InAs quantum dots grown on GaAs (511)A substrates has been studied by atomic force microscopy. According to the atomic force microscopy studies for quantum dots grown with varying InAs coverage, a noncoherent nucleation of quantum dots is observed. Moreover, due to the long migration length of In atoms, the Ostwald ripening process is aggravated, resulting in the bad uniformity of InAs quantum dots on GaAs (511)A. In order to improve the uniformity of nucleation, the growth rate is increased. By studying the effects of increased growth rates on the growth of InAs quantum dots, it is found that the uniformity of InAs quantum dots is greatly improved as the growth rates increase to 0.14 ML s−1. However, as the growth rates increase further, the uniformity of InAs quantum dots becomes dual‐mode, which can be attributed to the competition between Ostwald ripening and strain relaxation processes. The results in this work provide insights regarding the competition between thermal dynamical barriers and the growth kinetics in the growth of InAs quantum dots, and give guidance to improve the size uniformity of InAs quantum dots on (N11)A substrates.
Tailoring Enzyme‐Like Activities of Gold Nanoclusters by Polymeric Tertiary Amines for Protecting Neurons Against Oxidative Stress
Authors: Liu Ching‐Ping , Wu Te‐Haw , Lin Yu‐Lung , Liu Chia‐Yeh , Wang Sabrina , Lin Shu‐Yi
Published: June 2016

The cytotoxicity of nanozymes has drawn much attention recently because their peroxidase‐like activity can decompose hydrogen peroxide (H2O2) to produce highly toxic hydroxyl radicals (•OH) under acidic conditions. Although catalytic activities of nanozymes are highly associated with their surface properties, little is known about the mechanism underlying the surface coating‐mediated enzyme‐like activities. Herein, it is reported for the first time that amine‐terminated PAMAM dendrimer‐entrapped gold nanoclusters (AuNCs‐NH2) unexpectedly lose their peroxidase‐like activity while still retaining their catalase‐like activity in physiological conditions. Surprisingly, the methylated form of AuNCs‐NH2 (i.e., MAuNCs‐N+R3, where R = H or CH3) results in a dramatic recovery of the intrinsic peroxidase‐like activity while blocking most primary and tertiary amines (1°‐ and 3°‐amines) of dendrimers to form quaternary ammonium ions (4°‐amines). However, the hidden peroxidase‐like activity is also found in hydroxyl‐terminated dendrimer‐encapsulated AuNCs (AuNCs‐OH, inside backbone with 3°‐amines), indicating that 3°‐amines are dominant in mediating the peroxidase‐like activity. The possible mechanism is further confirmed that the enrichment of polymeric 3°‐amines on the surface of dendrimer‐encapsulated AuNCs provides sufficient suppression of the critical mediator •OH for the peroxidase‐like activity. Finally, it is demonstrated that AuNCs‐NH2 with diminished cytotoxicity have great potential for use in primary neuronal protection against oxidative damage.
Rhenium‐188 Labeled Tungsten Disulfide Nanoflakes for Self‐Sensitized, Near‐Infrared Enhanced Radioisotope Therapy
Authors: Chao Yu , Wang Guanglin , Liang Chao , Yi Xuan , Zhong Xiaoyan , Liu Jingjing , Gao Min , Yang Kai , Cheng Liang , Liu Zhuang
Published: June 2016

Radioisotope therapy (RIT), in which radioactive agents are administered or implanted into the body to irradiate tumors from the inside, is a clinically adopted cancer treatment method but still needs improvement to enhance its performances. Herein, it is found that polyethylene glycol (PEG) modified tungsten disulfide (WS2) nanoflakes can be easily labeled by 188Re, a widely used radioisotope for RIT, upon simple mixing. Like other high‐Z elements acting as radiosensitizers, tungsten in the obtained 188Re‐WS2‐PEG would be able to absorb ionization radiation generated from 188Re, enabling ‘‘self‐sensitization’’ to enhance the efficacy of RIT as demonstrated in carefully designed in vitro experiments of this study. In the meanwhile, the strong NIR absorbance of WS2‐PEG could be utilized for NIR light‐induced photothermal therapy (PTT), which if applied on tumors would be able to greatly relieve their hypoxia state and help to overcome hypoxia‐associated radioresistance of tumors. Therefore, with 188Re‐WS2‐PEG as a multifunctional agent, which shows efficient passive tumor homing after intravenous injection, in vivo self‐sensitized, NIR‐enhanced RIT cancer treatment is realized, achieving excellent tumor killing efficacy in a mouse tumor model. This work presents a new concept of applying nanotechnology in RIT, by delivering radioisotopes into tumors, self‐sensitizing the irradiation‐induced cell damage, and modulating the tumor hypoxia state to further enhance the therapeutic outcomes.
Lanthanide Ion Doped Upconverting Nanoparticles: Synthesis, Structure and Properties
Authors: Yan Chenglin , Zhao Haiguang , Perepichka Dmitrii F. , Rosei Federico
Published: June 2016

Lanthanide doped upconverting nanoparticles (UCNPs) have emerged as a new class of luminescent materials, with major discoveries and overall significant progress during the last decade. Unlike multiphoton absorption in organic dyes or semiconductor quantum dots, lanthanide doped UCNPs involve real intermediate quantum states and convert infrared (IR) into visible light via sequential electronic excitation. The relatively high efficiency of this process even at low radiation flux makes UCNPs particularly attractive for many current and emerging areas of technology. The aim of this article is to highlight several recent advances in this rapidly growing field, emphasizing the relationships between structure and properties of UCNPs. Additionally, various strategies developed for the synthesis of UCNPs with a focus on the various synthetic approaches that yield high‐quality monodisperse samples with controlled size, shape and crystalline phase are reviewed. Emerging synthetic approaches towards designed structure to improve the optical and electronic properties of UCNPs are discussed. Finally, recent examples of applications of UCNPs in biomedical and optoelectronics research, giving our own perspectives on future directions and emerging possibilities of the field are described.
Tubular g‐C3N4 Isotype Heterojunction: Enhanced Visible‐Light Photocatalytic Activity through Cooperative Manipulation of Oriented Electron and Hole Transfer
Authors: Tong Zhenwei , Yang Dong , Sun Yuanyuan , Nan Yanhu , Jiang Zhongyi
Published: June 2016

A tubular g‐C3N4 isotype heterojunction (TCNH) photocatalyst was designed for cooperative manipulation of the oriented transfer of photogenerated electrons and holes to pursue high catalytic performance. The adduct of cyanuric acid and melamine (CA·M) is first hydrothermally treated to assemble into hexagonal prism crystals; then the hybrid precursors of urea and CA·M crystals are calcined to form tubular g‐C3N4 isotype heterojunctions. Upon visible‐light irradiation, the photogenerated electrons transfer from g‐C3N4 (CA·M) to g‐C3N4 (urea) driven by the conduction band offset of 0.05 eV, while the photogenerated holes transfer from g‐C3N4 (urea) to g‐C3N4 (CA·M) driven by the valence band offset of 0.18 eV, which renders oriented transfer of the charge carriers across the heterojunction interface. Meanwhile, the tubular structure of TCNH is favorable for oriented electron transfer along the longitudinal dimension, which greatly decreases the chance of charge carrier recombination. Consequently, TCNH exhibits a high hydrogen evolution rate of 63 μmol h−1 (0.04 g, λ > 420 nm), which is nearly five times of the pristine g‐C3N4 and higher than most of the existing g‐C3N4 photocatalysts. This study demonstrates that isotype heterojunction structure and tubular structure can jointly manipulate the oriented transfer of electrons and holes, thus facilitating the visible‐light photocatalysis.
Advances in Gold Catalysis and Understanding the Catalytic Mechanism
Authors: Ishida Tamao , Koga Hiroaki , Okumura Mitsutaka , Haruta Masatake
Published: June 2016

When gold is deposited as nanoparticles (NPs) with mean diameters of 2–5 nm or clusters with mean diameters below 2 nm onto a variety of supports such as metal oxides, carbons, polymers, etc., the supported Au NPs exhibit unique catalytic properties, while bulk Au is almost inert as a catalyst. A lot of research works indicate that the key factors of the catalysis by supported Au NPs are the selection of the supports, the control of the Au NP size, the shape of the Au NPs, and the strong junction between Au NPs and the supports, because the perimeter zone around Au NPs acts as the active site for many reactions. In order to elucidate the origin of catalysis by supported Au NPs, the interplay between physicochemical analysis, computational studies, and rational experiments for catalysis by supported Au NPs is becoming more and more important. This article summarizes our experiences and progress in such interplay.