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In situ uniform confinement of ultrasmall Mo2C nanocrystals into micropore-enriched N-doped carbons was achieved by carbonizing phosphomolybdic acid/polyimide precursors to craft a surface-dominated capacitive battery-type anode. Upon coupling with a capacitor-type cathode, the as-fabricated lithium-ion capacitors exhibit superior power and energy outputs by improving the kinetics and capacity imbalance between two electrodes.

Organic polyimides have received an ever-growing interest in lithium-ion batteries based on the reversible anion stabilization mechanism of redox-active carbonyl groups due to their high theoretical capacities, resource sustainability, and diverse chain structures. Herein, four linear polyimides with different chain structures were synthesized by a facile and green hydrothermal method. The chain structure-electrochemical performance relationship was explored by regulating active anhydride units and diamine linkers. The incorporation of flexible linkers between redox-active anhydrides results in the facile movement of polyimide chains and the formation of porous networks with abundant active sites. In contrast, rigid aromatic linkers with strong π–π conjugation tend to assemble into the orderly-stacked sheets, enabling the efficient electron transfer. When used as the battery cathode, 1,4,5,8-naphthalenetetracarboxylic dianhydride-based polyimide with a relatively flexible linker delivers the largest specific capacity. Such a polyimide also demonstrates the high cycling stability with a capacity retention up to 52% over 10000 cycles. In contrast, pyromellitic dianhydride-based polyimide with a benzene-enriched linker exhibits the lowest capacity and poor rate capability due to its densely-stacked sheets and limited exposure of active groups. The chain structure-dependent performance relationship of polyimides would offer new insights into the rational design of high-performance organic electrodes for the next-generation batteries.

A pairwise coupling of 0D Super-P (SP), 1D carbon nanotubes (CNTs), and 2D graphene nanosheets (GNs) into binary carbon-based conductive additives was used here for the LiFePO4 cathode in lithium-ion batteries. For comparison, the LiFePO4 cathode with SP, CNT, or GN unitary conductive agent was also examined. Electrochemical test results suggest that the cathodes with binary conducting additives present greatly improved electrochemical performance than the traditional cathode system (only SP used). Especially, the LiFePO4 cathode containing 3% CNT component exhibits the highest specific capacity and the best cycling stability among all the cathodes with binary conducting additives, indicating that an appropriate amount of CNTs is critical in enhancing the conductivity and practical capacity output. However, an excess of CNTs leads to entangling with each other, hampering the uniform distribution of active materials and resulting in poor electrode performance. Furthermore, the combination of CNT and GN can effectively improve the capacity and cycling stability of the LiFePO4 cathodes due to the synergistic effect of 3D conductive networks constructed by the two.

Supplemental Digital Content is available in the text, Background: Zika virus (ZIKV) has emerged as a global pathogen causing significant public health concerns. China has reported several imported cases where ZIKV were carried by travelers who frequently travel between China and ZIKV-endemic regions. To fully characterize the ZIKV strains isolated from the cases reported in China and assess the risk of ZIKV transmission in China, comprehensive phylogenetic and genetic analyses were performed both on all ZIKV sequences of China and on a group of scientifically selected ZIKV sequences reported in some of the top interested destinations for Chinese travelers. Methods: ZIKV genomic sequences were retrieved from the National Center for Biotechnology Information database through stratified sampling. Recombination event detection, maximum likelihood (ML) phylogenetic analysis, molecular clock analysis, selection pressure analysis, and amino acid substitution analysis were used to reconstruct the epidemiology and molecular transmission of ZIKV. Results: The present study investigated 18 ZIKV sequences from China and 70 sequences from 16 selected countries. Recombination events rarely happens in all ZIKV Asian lineage. ZIKV genomes were generally undergone episodic positive selection (17 sites), and only one site was under pervasive positive selection. All ZIKV imported into China were Asian lineage and were assigned into two clusters: Venezuela-origin (cluster A) and Samoa-origin cluster (cluster B) with common ancestor from French Polynesia. The time of most recent common ancestors of Cluster A dated to approximately 2013/11 (95% highest posterior density [HPD] 2013/06, 2014/03) and cluster B dated to 2014/08 (95% HPD 2014/02, 2015/01). Cluster B is more variable than Cluster A in comparison with other clusters, but no varied site of biological significance was revealed. ZIKV strains in Southeast Asia countries are independent from strains in America epidemics. Conclusions: The genetic evolution of ZIKV is conservative. There are two independent introductions of ZIKV into China and China is in danger of autochthonous transmission of ZIKV because of high-risk surrounding areas. Southeast Asia areas have high risk of originating the next large-scale epidemic ZIKV strains.

BackgroundIn general, children with COVID-19 have milder illness and better prognosis compared to adults. However, the neonatal population (from birth to 28 days of life) may be more vulnerable to severe COVID-19 disease due to the immaturity of neonatal immune system and possibility of in-utero infection from infected mothers. Comprehensive data on neonatal COVID-19 manifestations is currently lacking.ObjectivesWe aimed to determine the clinical manifestations and outcomes of neonates with COVID-19, and characterise these clinical characteristics based on illness severity.MethodsA systematic review (CRD42020183500) was conducted following the PRISMA guidelines with Embase, PubMed, and China Knowledge Resource Integrated (CNKI) databases until 1 August 2020. Additional studies were identified from references of included studies and the John Hopkins Centre for Humanitarian Health database. Studies reporting neonates (≤ 28 days old) who tested positive for SARS-CoV-2 by reverse transcriptase PCR (RT-PCR) were included. Descriptive statistics were used to compare mild-moderately ill neonates (non-severe group) with severely-critically ill neonates (severe group). This grouping was based on the World Health Organization’s definition. Continuous variables were analysed using Wilcoxon-Rank Sum Test. Dichotomous or categorical data were analysed with Chi-square and Fisher’s Exact Tests. Quality of the studies were reviewed with Newcastle-Ottawa Scale and Murad Tool.ResultsSixty-seven studies were included out of 199 full text articles screened. Studies comprised of case reports, case series or cohort studies. Of ninety-nine neonates with COVID-19 infection, 72 (72.7%) were symptomatic. Amongst the symptomatic neonates, respiratory symptoms were common: shortness of breath (36.1%), nasal symptoms (19.4%), cough (18.1%). Other symptoms included fever (55.6%), feeding problems (31.9%) and gastrointestinal (GI) symptoms (16.7%). Lymphopenia was present in 43.9% (18 of 41 neonates tested). Elevated C-reactive protein was only reported in 13.2% (5 of 38 neonates tested), while 65.4% (34 of 52 neonates) had chest radiographs suggestive of pneumonia. Thirty neonates (30.3%) had severe-critical illness (severe group), while 69 (69.9%) had mild-moderate illness (non-severe group). Compared with the non-severe group, more neonates in the severe group were symptomatic (100% vs 60.9%, p

Objective Synthesise evidence on production of SARS-CoV-2 antibodies in human milk of individuals who had COVID-19, and antibodies’ ability to neutralise SARS-CoV-2 infectivity. Design A systematic review of studies published from 1 December 2019 to 16 February 2021 without study design restrictions. Setting Data were sourced from PubMed, MEDLINE, Embase, CNKI, CINAHL and WHO COVID-19 database. Search was also performed through reviewing references of selected articles, Google Scholar and preprint servers. Studies that tested human milk for antibodies to SARS-CoV-2 were included. Patients Individuals with COVID-19 infection and human milk tested for anti-SARS-CoV-2 neutralising antibodies. Main outcome measures The presence of neutralising antibodies in milk samples provided by individuals with COVID-19 infection. Results Individual participant data from 161 persons (14 studies) were extracted and re-pooled. Milk from 133 (82.6%) individuals demonstrated the presence of anti-SARS-CoV-2 immunoglobulin A (IgA), IgM and/or IgG. Illness severity data were available in 146 individuals; 5 (3.4%) had severe disease, 128 (87.7%) had mild disease, while 13 (8.9%) were asymptomatic. Presence of neutralising antibodies in milk from 20 (41.7%) of 48 individuals neutralised SARS-CoV-2 infectivity in vitro. Neutralising capacity of antibodies was lost after Holder pasteurisation but preserved after high-pressure pasteurisation. Conclusion Human milk of lactating individuals after COVID-19 infection contains anti-SARS-CoV-2-specific IgG, IgM and/or IgA, even after mild or asymptomatic infection. Current evidence demonstrates that these antibodies can neutralise SARS-CoV-2 virus in vitro. Holder pasteurisation deactivates SARS-CoV-2-specific IgA, while high-pressure pasteurisation preserves the SARS-CoV-2-specific IgA function., Systematic review on the titers and neutralising capacity of SARS-CoV-2-specific antibodies in human milk demonstrates that these antibodies can neutralise the virus in vitro. Furthermore, high pressure, but not Holder pasteurisation deactivates the specific IgAs.

This paper presents the retrieval of effective permittivity and permeability of periodic structure on dielectric and magnetic substrates. The retrieval approach is based on investigating the equivalent circuits of periodic structures. For demonstration, a single square loop-based periodic structure is served as an example to elaborate the retrieval process. First, the equivalent circuit of the freestanding single square loop-based structure is modelled with inductor and capacitor, where the values of these components are determined by the simulated Z-matrix of the free-standing structure; the effects of supporting substrates (dielectric or magnetic substrates) are then considered, where the compensating principles are deduced from inductive grids and capacitive patches periodic structures to compensate the corresponding values in the former equivalent circuit on purpose. The compensating values are also determined from the simulated S-parameter of the structure with supporting substrates. The formulas of effective permittivity and permeability are readily deduced and obtained from the original and compensating values of components in the equivalent circuits. The proposed retrieval process provides a new understanding of effective permittivity and permeability of periodic structures.

Immune checkpoint inhibitors (ICIs) have improved clinical outcomes with a number of advanced malignancies. However, diverse immune-related adverse events (iRAEs) occurred with the widespread use of ICIs, some of which are rarely and life-threatening. Here we report a 66-year-old patient with lung adenocarcinoma who received two doses of sintilimab, a human monoclonal antibody against programmed cell death-1 (PD-1), experienced a fatal storm of iRAEs. He was admitted to the intensive care unit (ICU) by immune induced-myositis/myocarditis and rhabdomyolysis. Despite immediate immunosuppressive therapy with methylprednisolone (MP) and immunoglobulin intravenously, he developed into myositis-myasthenia gravis (MG) overlap syndrome complicated with myasthenia crisis. We commenced plasma exchange (PLEX), mechanical ventilation, immunosuppressive therapy, as well as other supportive therapies. Three months later, the patient's serum creatine phosphate kinase (CPK) and anti-acetylcholine receptor antibody (anti-AChR-Ab) returned to normal despite tumor progression. Herein we discuss the incidence, operating mechanism and management strategies of the fatal iRAEs. Early admission to the ICU and multidisciplinary collaborative treatment for unstable patients with iRAEs could help to achieve a favorable outcome.

Lithium-sulfur (Li–S) batteries have been regarded as the most promising next-generation energy storage devices due to their large specific capacity and high energy density. However, their practical implementation is still subjected to the insulation of sulfur and discharge products, serious shuttle effect, and large volume expansion of sulfur during the discharge/charge processes. Herein, polyimide nanoarrays functionalized carbon nanotubes (PI@CNTs) were proposed as a sulfur host with the incorporation of additional carbon nanotubes (CNTs) conductive networks. The as-preformed polyimide nanoarrays on the surface of CNTs expose sufficient adsorption sites for sulfur loading. PI@CNTs chemically bind lithium polysulfides (LiPS) via the polar Li–N bonding interaction and physically confine LiPS in the network. Meanwhile, the intertwined frameworks can bear the volume expansion of sulfur and maintain the electrode integrity. The PI@CNT/CNT/S cathode exhibits the sulfur loading as high as 70 wt% and shows the cycling stability with a capacity retention of 67% after 300 cycles at 1C. Furthermore, the additional incorporation of CNTs can form continuous electron transfer paths, thereby promoting the rate capability. This work integrated the polar polymer host and conductive networks with robust LiPS trapping and fast conversion, and would propose a new paradigm for designing high-performance sulfur cathodes.

A low radar cross section (RCS) antenna designed with band-notched absorber is described. First, a dual-polarization absorber with relative bandwidth more than 80% is designed using loaded resistors. Pairs of circular slot resonators and metal strip array resonators are introduced in the absorber to realize a notch band with full reflectance in the vertical polarization, while a wide absorption band in the horizontal polarization is maintained. The proposed band-notched absorber is thus realized. Within the notch band, the absorber can be served as a metal ground for antenna; while a great RCS reduction is obtained out of the notch band and in the horizontal polarization band. Then, a dipole antenna rigorously designed is mounted above the band-notched absorber, whose operating frequency is exactly in accordance with that of the notch band. The proposed low RCS antenna is established based on assembling the dipole antenna and the band-notched absorber together. The measured results demonstrate that the proposed antenna has fairly good radiation patterns. Added to that, more than 10 dB RCS reduction in two polarizations is realized simultaneously compared with that one of a conventional dipole antenna.

A low radar cross section (RCS) and low profile antenna co-designed with absorbent frequency selective radome (AFSR) is investigated. A pair of circular slot resonators is embedded on surface of the AFSR to realize a transmission window in the vertical polarization, while the wide absorption band is still maintained in the horizontal polarization. When a patch antenna is etched within the AFSR, where the metal grounds of the patch antenna and AFSR are co-used, the co-designed antenna with low RCS and low profile is thus realized. For demonstration, an AFSR is designed with its transmission window has a minimal insertion loss of 0.45 dB at 8.9 GHz, and two separate absorption bands (a lower absorption band from 4.8 to 7.5 GHz and an upper absorption band from 10 to 13 GHz) in the vertical polarization, a wide absorption band (from 4.5 to 12.5 GHz) in the horizontal polarization. A patch antenna etched within the AFSR is optimized to operate at 8.9 GHz, then it is simulated and fabricated. The measured results demonstrate that the proposed antenna not only has good radiation patterns, but also obtains significant RCS reduction.

In this paper, a band-notched absorber with high notch-band-edge selectivity is proposed and investigated. It is formed by introducing a narrower and full reflectance band into a wider absorption band. For each absorbing unit cell, two independently magnetic and electric resonances with adjacent resonant frequencies are employed to develop the narrower and full reflectance band, while a dipole-shaped metal strip with a resister printed on one side of the supporting substrate and a ground plane is used to realize the wider absorption band. By retrieving relative equivalent circuits of each cell, the performance of the proposed absorber can be qualitatively analyzed. Simply through tuning the frequencies of the independently magnetic and electric resonances, the performance of the notched band can be adjusted with high notch-band-edge selectivity. A sample of an absorber with the notched band frequency from 8.2 to 9.8 GHz, good absorption band from 4.8 to 8.0 GHz and 10.2 to 16 GHz has been designed, fabricated, and measured. Good agreement among circuit analysis, simulation results, and measurement results is finally obtained.

Non-precious iron-nitrogen doped carbon material (Fe-N/C) is the most promising candidate to replace platinum-based catalysts for oxygen reduction reaction (ORR) taking place at the cathode in fuel cells. In this study, three-dimensionally (3D) ordered mesoporous Fe-N/C with open porous structure is successfully synthesized. The obtained shape is a rhombic dodecahedron which corresponds to a single mesoporous crystal with body-centered cubic structure (Im-3m). By applying an optimal post-treatment of NH3 activation, a high content of beneficial pyridinic nitrogen can be doped while maintaining the ordered mesoporous architecture with high surface area and large pore volume. Our mesoporous Fe-N/C greatly promotes ORR performance with a high onset potential of 1.018 V and limited-diffusion current density of 5.98 mA cm−2 in alkaline electrolyte. Interestingly, this mesoporous Fe-N/C also shows good ORR catalytic activity in acidic condition with onset potential and limited-diffusion current density as high as 0.935 V and 5.60 mA cm-2, respectively.

A highly integrated tunable triple-band patch antenna is designed and fabricated. Two U-slots are cut in the same radiating patch to achieve triple-band performance. While the antenna miniaturization is obtained by loading one patch edge with metalized vias, theory of characteristic modes is adopted to explain the U-slots scaling. The antenna radiating patch size is only 0.1λ 0 × 0.17λ 0 . The operating frequencies can be independently tuned after properly inserting three varactor diodes into the radiating structure. The radiation patterns have similar unidirectional shapes with high stability of the resonant frequencies during the entire tuning of each band. Good agreement between simulation and measurement results is obtained. The antenna covers the following bands: 2.07-2.6 GHz, 2.86-3.57 GHz, and 4.59-5.39 GHz. The measured peak gains and efficiencies are 2.72 dBi and 62.6%, 2.76 dBi and 63.3%, and 2.87 dBi and 66.8%, respectively. Size reduction, multiband function, and independent tuning of three operating bands using only one antenna layer and one RF feedline are combined together to realize a compact and practical antenna.

A novel method of developing an electromagnetic absorber is proposed through the design of an ultrawideband resistor-loaded planar dipole absorber. With the method, an antenna array structure is first designed for its best transmission performance and configured as an absorber with the application of the reciprocal principle. The designed planar dipole antenna has achieved a fractional bandwidth of 105% for an absorbing rate of more than 90% under the normal incident. In addition, the thickness of the proposed structure is $0.128\lambda _{0} $ with $\lambda _{0} $ being the wavelength at the center operating frequency. Good agreement between the simulated and measured results demonstrates the validity of the proposed method.

This letter presents an absorptive Fabry-Perot polarizer and its application on the antenna for gain enhancement and cross-polarization level reduction. The proposed polarizer is designed to achieve a partial reflectance/transmission and an electromagnetic wave absorptivity more than 90% over 4.5-7.5 GHz in horizontal and vertical polarization, respectively. Equivalent circuits of the proposed polarizer are established to explicitly analyze the performance of the proposed polarizer. A rectangular patch antenna operating at 5.8 GHz, as the source antenna, is rigorously assembled with the proposed polarizer. The simulated results, compared to the source antenna, demonstrate significant gain enhancement (around 8 dB) and cross-polarization level reduction (more than 10 dB), which is experimentally verified by the measured results.

This letter proposes a millimeter-wave gain-filtering transmitarray (TA) antenna using a hybrid lens. The hybrid lens is incorporated by a substrate integrated waveguide (SIW) cavity bandpass filter and a dielectric lens. The dielectric lens serving as a phase shifter is seamlessly coated on the SIW bandpass filter to achieve a codesigned architecture. The proposed hybrid lens unit cell (UC) is required not only to fulfill the desired phase shifts but also maintain a stable bandpass response, simultaneously. Therefore, the specific shape of the dielectric-lens UC must be optimized to minimize its impacts on the bandpass response of the original SIW bandpass filter as much as possible to ensure the filtering performance of the proposed hybrid-lens UC. After some optimizations, the dielectric-lens UC based on the air-perforated dielectric square post (APDSP) is determined finally. The simulated results show that the bandpass responses of the hybrid-lens UC are still maintained when the profile of the APDSP-based dielectric-lens UC is varied to satisfy a full phase-cycle (2π). The proposed hybrid-lens UCs are arranged reasonably to construct a TA antenna to fulfill the high gain and gain-filtering performance. The simulated and measured results are consistent, revealing the proposed TA antenna has a gain of 25.5 dBi at 35 GHz and a bandpass gain-filtering response over 30-40 GHz.

The small-angle neutron scattering (SANS) spectrometer Suanni at the liquid hydrogen cold neutron source of the 20 MW China Mianyang Research Reactor has recently been upgraded. Ultra-thin biconcave MgF2lenses with a central thickness down to 0.2 mm have been installed between the collimator chamber and the sample stage. The lenses are able to improve the flux without too excessive an increase in the neutron beam size on the detector. A smaller minimumQ(Qmin) can be obtained by decreasing the beam size without changing the total length of the spectrometer. By testing the central beam profiles under different neutron wavelengths (∼0.56–1 nm) with both traditional pinhole SANS (PSANS) and focusing SANS (FSANS) geometries, the gain factor thanks to the neutron lenses is about one order of magnitude. Given the loss of intensity due to the absorption of neutrons by the lenses, the benefits of the focusing can only be realized if it is possible to increase the aperture size. With an identical source aperture, FSANS can minimize the nominalQminfrom 7.20 × 10−3 nm−1(for PSANS) to 5.55 × 10−3 nm−1at a neutron wavelength of 1 nm. The practical benefit provided by the lenses is verified with a solution of poly(methyl methacrylate) nanospheres, which yields a scattering intensity one order of magnitude higher and a better resolution with the FSANS geometry than with that of PSANS.

A new pinhole small-angle neutron scattering (SANS) spectrometer, installed at the cold neutron source of the 20 MW China Mianyang Research Reactor (CMRR) in the Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, has been put into use since 2014. The spectrometer is equipped with a multi-blade mechanical velocity selector, a multi-beam collimation system, and a two-dimensional He-3 position sensitive neutron detector. The q -range of the spectrometer covers from 0.01 nm −1 to 5.0 nm −1 . In this paper, the design and characteristics of the SANS spectrometer are described. The q -resolution calculations, together with calibration measurements of silver behenate and a dispersion of nearly monodisperse poly-methyl-methacrylate nanoparticles indicate that our SANS spectrometer has a good performance and is now in routine service.

The ordered mesoporous material Cu–SBA-15 was synthesized under neutral condition via a one-step method that uses hydroxyl radicals instead of inorganic acid. The obtained samples were systematically analyzed by XRD, SEM, TEM, UV–vis DRS, ICP–OES, N2 adsorption, and NH3–TPD. The adsorption and oxidation catalytic properties of SBA-15 were also investigated via the oxidative decolorization of organic dyes as a model reaction. Results illustrated that Cu–SBA-15 has an ordered mesoporous structure with homogeneous pore distribution and acid sites with a Cu/Si molar ratio of 0.034. Cu2+ ions incorporate homogeneously into the framework of the mesoporous silica rather than be at the extra-framework position in the form of CuO nanoparticles. Acetate ions not only accelerate the nucleation and crystallization of mesoporous silica but also contribute to the doping of Cu ions into the SBA-15 framework. Cu–SBA-15 materials exhibit a favorable catalytic activity in the oxidation degradation of organic dyes compared with CuO and Cu ion-exchanged Al–SAB-15.

Background Current high-throughput sequencing platforms provide capacity to sequence multiple samples in parallel. Different samples are labeled by attaching a short sample specific nucleotide sequence, barcode, to each DNA molecule prior pooling them into a mix containing a number of libraries to be sequenced simultaneously. After sequencing, the samples are binned by identifying the barcode sequence within each sequence read. In order to tolerate sequencing errors, barcodes should be sufficiently apart from each other in sequence space. An additional constraint due to both nucleotide usage and basecalling accuracy is that the proportion of different nucleotides should be in balance in each barcode position. The number of samples to be mixed in each sequencing run may vary and this introduces a problem how to select the best subset of available barcodes at sequencing core facility for each sequencing run. There are plenty of tools available for de novo barcode design, but they are not suitable for subset selection. Results We have developed a tool which can be used for three different tasks: 1) selecting an optimal barcode set from a larger set of candidates, 2) checking the compatibility of user-defined set of barcodes, e.g. whether two or more libraries with existing barcodes can be combined in a single sequencing pool, and 3) augmenting an existing set of barcodes. In our approach the selection process is formulated as a minimization problem. We define the cost function and a set of constraints and use integer programming to solve the resulting combinatorial problem. Based on the desired number of barcodes to be selected and the set of candidate sequences given by user, the necessary constraints are automatically generated and the optimal solution can be found. The method is implemented in C programming language and web interface is available at http://ekhidna2.biocenter.helsinki.fi/barcosel. Conclusions Increasing capacity of sequencing platforms raises the challenge of mixing barcodes. Our method allows the user to select a given number of barcodes among the larger existing barcode set so that both sequencing errors are tolerated and the nucleotide balance is optimized. The tool is easy to access via web browser. Electronic supplementary material The online version of this article (10.1186/s12859-018-2262-7) contains supplementary material, which is available to authorized users.

Mesoporous vanadium phosphate (VOPO4) nanosheets have been successfully synthesized through an easy and reproducible lyotropic liquid crystals (LLC) templating approach for the first time. Using the triblock copolymer (P123) as a surfactant, VOPO4 precursor with a well-developed 2D hexagonal mesostructure can be obtained. Following complete removal of the template by calcination, crystallized VOPO4 frameworks with less-ordered mesostructure are achieved. The as-prepared mesoporous VOPO4 nanosheets exhibit superior pseudocapacitive performance (767 F g‒1 at 0.5A g‒1) by virtue of the favorable mesostructure that gives rise to abundant easily accessible redox active sites as well as reinforced charge transfer and ion diffusion properties. The charge storage mechanism of the mesoporous VOPO4 nanosheets has been experimentally demonstrated to be based on the reversible two-step redox reactions between V(V) and V(III) in acidic medium. This advantageous LLC templating strategy is expected to open up a new route for designing various mesoporous metal phosphates with superior electrochemical performance for utilization in energy storage devices. This work was supported by the Australian Research Council (ARC) Future Fellow ( FT150100479 ), JSPS KAKENHI ( 17H05393 and 17K19044 ), and the research fund by the Suzuken Memorial Foundation. Appendix A

Background: Supportive educational programs during the perinatal period are scarce in Singapore. There is no continuity of care available in terms of support from community care nurses in Singapore. Parents are left on their own most of the time, which results in a stressful transition to parenthood. There is a need for easily accessible technology-based educational programs that can support parents during this crucial perinatal period. Objective: The aim of this study was to describe the study protocol of a randomized controlled trial on a technology-based supportive educational parenting program. Methods: A randomized controlled two-group pretest and repeated posttest experimental design will be used. The study will recruit 118 parents (59 couples) from the antenatal clinics of a tertiary public hospital in Singapore. Eligible parents will be randomly allocated to receive either the supportive educational parenting program or routine perinatal care from the hospital. Outcome measures include parenting self-efficacy, parental bonding, postnatal depression, social support, parenting satisfaction, and cost evaluation. Data will be collected at the antenatal period, immediate postnatal period, and at 1 month and 3 months post childbirth. Results: Recruitment of the study participants commenced in December 2016 and is still ongoing. Data collection is projected to finish within 12 months, by December 2017. Conclusions: This study will identify a potentially clinically useful, effective, and cost-effective supportive educational parenting program to improve parental self-efficacy and bonding in newborn care, which will then improve parents’ social support–seeking behaviors, emotional well-being, and satisfaction with parenting. It is hoped that better supported and satisfied parents will consider having more children, which may in turn influence Singapore’s ailing birth rate. Trial Registration: International Standard Randomized Controlled Trial Number (ISRCTN): 48536064; https://www.isrctn.com/ISRCTN48536064 (Archived by WebCite at http://www.webcitation.org/6wMuEysiO) [JMIR Res Protoc 2018;7(1):e4]

A low radar cross section antenna based on band-notched absorber is described in this paper. Firstly, the band-notched absorber is formed by introducing a notch band with full reflectance performance into a wider absorption band. For each absorbing cell unit, two independently magnetic and electric resonances with adjacent resonant frequencies are employed to develop the notch band, while a dipole-shaped metal strip with a resistor printed on one side of the supporting substrate and a ground plane are used to realize the wider absorption band. Within the notch band, the absorber can be served as a metal ground for antenna, while there will exist a good absorption performances out of the notch band, a significant RCS reduction is thus obtained. A dipole antenna is rigorously designed based on the frequencies of the notch band. The proposed low RCS antenna is established based on assembling the dipole antenna and the absorber together. The measured results demonstrate that the proposed low RCS antenna has fairly good radiation patterns, and more than 10dB RCS reduction out of the notch band is also realized simultaneously.

Cationic and anionic doping in LiNi0.5Mn1.5O4 has been prepared via a solid state method. The effect of substitution on the structure, morphology, and electrochemical properties were investigated. The XRD and Raman results indicate that all synthesized materials have a phase-pure spinel structure with a space group of Fd3 m and no obvious impurity phase peaks. Excellent cycle life is measured for these 5 V Cr and (or) F-doped electrodes. When the charge/discharge rate returns to 1 C after the test of rate capability (0.1-5 C), the capacity can be completely recovered and the capacity retention is about 98.6%, 98.8% and 96.2% after 100 cycles for LiNi0.45Cr0.05Mn1.5O4, LiNi0.45Cr0.05Mn1.5O3.9F0.1 and LiNi0.5Mn1.5O3.9F0.1, respectively. Furthermore, rate capability is greatly influenced by the relative content of Mn3+. Cr and (or) F substitutions supply an efficient process to tune the Mn3+ concentration in the lattice.

Nowadays one of the principal challenges for the development of lithium-ion batteries (LIBs) is fulfilling the burgeoning demands for high energy and power density with long cycle life. Herein, we demonstrate a two-step route for synthesizing LiV3O8 nanorods with a confined preferential orientation by using VO2(B) nanosheets made in the laboratory as the precursor. The special structures of nanorods endow the LiV3O8 materials with markedly enhanced reversible capacities, high-rate capability and long-term cycling stability as cathodes for lithium storage. The results show that very desirable initial capacities of 161 and 158 mA h g−1 can be achieved for the LiV3O8 nanorods at extremely high rates of 2000 and 3000 mA g−1, with minimal capacity loss of 0.037% and 0.031% per cycle throughout 300 and 500 cycles, respectively. The energetically optimized electron conduction and lithium diffusion kinetics in the electrode process may shed light on the superior electrochemical properties of the LiV3O8 nanorods, primarily benefitting from the small particle size, large surface area and restricted preferential ordering along the (100) plane.

Background: Transitioning into parenthood can be stressful for new parents, especially with the lack of continuity of care from health care professionals during the postpartum period. Short hospital stays limit the availability of support and time parents need to be well equipped with parenting and infant care skills. Poor parental adjustment may, in turn, lead to negative parental outcomes and adversely affect the child’s development. For the family’s future well-being, and to facilitate a smoother transition into parenthood, there is a need for easily accessible, technology-based educational programs to support parents during the crucial perinatal period. Objective: This study aimed to examine the effectiveness of a technology-based supportive educational parenting program (SEPP) on parenting outcomes during the perinatal period in couples. Methods: A randomized, single-blinded, parallel-armed, controlled trial was conducted. The study recruited 236 parents (118 couples) from an antenatal clinic of a tertiary hospital in Singapore. Eligible parents were randomly assigned to the intervention group (n=118) or the control group (n=118). The SEPP is based on Bandura’s self-efficacy theory and Bowlby’s theory of attachment. Components of the intervention include 2 telephone-based educational sessions (1 antenatal and 1 immediately postnatal) and a mobile health app follow-up for 1 month. The control group only received routine perinatal care provided by the hospital. Outcome measures including parenting self-efficacy (PSE), parental bonding, perceived social support, parenting satisfaction, postnatal depression (PND), and anxiety were measured using reliable and valid instruments. Data were collected over 6 months at 4 time points: during pregnancy (third trimester), 2 days postpartum, 1 month postpartum, and 3 months postpartum. Outcomes were standardized using baseline means and SDs. Linear mixed models were used to compare the groups for postpartum changes in the outcome variables. Results: The intervention group showed significantly better outcome scores than the control group from baseline to 3 months postpartum for PSE (mean difference, MD, 0.37; 95% CI 0.06 to 0.68; P=.02), parental bonding (MD −1.32; 95% CI −1.89 to −0.75; P

Multiporous MnCo2O4 microspheres are fabricated via the solvothermal method followed by pyrolysis of carbonate precursor to demonstrate excellent bifunctional catalytic activity toward both the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). Because of this multiporous structure, the resulting MnCo2O4 microspheres show an efficient electrocatalytic performance in LiTFSI/TEGDME electrolyte-based Li–O2 batteries. MnCo2O4 microspheres as the air cathode deliver better performance during the discharging and charging processes and good cycle stability compared with that of the Super P. This preliminary result manifests that multiporous MnCo2O4 microspheres are promising cathode catalysts for nonaqueous Li–O2 batteries.

To calibrate quickly key parameters of a small angle neutron scattering spectrometer,such as selecting neutron wavelengths,wavelength resolution,and the Q resolution under a geometrical layout of the spectrometer,the experiment data of small angle neutron scattering for silver behenate powder were fitted.First,the geometrical layout of spectrometer was chosen including the size of circular source,sample apertures of the collimator,the source-to-sample distance and the sample-to-detector distance.Then,the spectra of small angle neutron scattering on silver behenate were obtained under four different revolving speeds of mechanical velocity selector.Finally,these experiment data were inversed and analyzed.Obtained results show that the velocity selector constant is 2 329.2 r·m-1·nm,correspondingly,four different selecting neutron wavelengths are 0.776、0.582、0.466、0.388 nm,respectively.The wavelength resolution of the velocity selector is 23.75% by fitting these experiment data and the spectrometer Q resolution curves can be obtained by using the chosen layout parameter and different rotating speeds.It concludes that the key parameters of small angle neutron scattering spectrometer can be achieved by using silver behenate,which supports the exact analysis and inversion for experiment data of small angle neutron scattering.

IM:To describe a study protocol that evaluates the effectiveness of the 'Home-but not Alone' educational programme delivered via a mobile health application in improving parenting outcomes.BACKGROUND:The postnatal period is a stressful period that poses numerous challenges for parents. To ensure a smooth transition, it is important to support these parents during this demanding period. Meanwhile, the development in mobile-based technology gives us the opportunity to develop an accessible educational programme that can be potentially beneficial for new parents. However, there is a scarcity of theory-based educational programmes that have incorporated technology such as a mobile health application in the early postpartum period.DESIGN:A randomized controlled trial with a two-group pre-test and post-test design.METHODS:The data will be collected from 118 couples, including both first-time parents and parents already with kids on the day of their discharge from a public hospital. Eligible parents will be randomly allocated to either a control group (receiving routine care) or an intervention group (routine care plus access to the 'Home-but not Alone' mobile health application. Outcome measures comprise of parenting self-efficacy, social support, parenting satisfaction and postnatal depression. Data will be collected at the baseline (on the day of discharge) and at four weeks postpartum.DISCUSSION:This will be an empirical study that evaluates a theory-based educational programme delivered via an innovative mobile health application on parental outcomes. Results from this study will enhance parenting self-efficacy, social support and parenting satisfaction, which may then reduce parental risks of postnatal depression.

An active antenna based on SPDT (single-pole double throw) switch which forms three beams with two horns is presented in this paper. The antenna which centers at 110GHz can get a maximal gain of about 17.7dB. The Y-shaped microwave switch, with an included angle of 90 degree, has a good impendence matching when single-arm or both-arms are on. The horn antenna is connected to the end of the switch as shown in Fig.1. A lateral radiation can be obtained when either arm of the switch is on, while a synthetic beam obtained with both arms on, thus forming three beams. These antennas can have a great usage in the application of THz sensing or detecting.

A new type of mesoporous silica nanoparticle (MSN) was synthesized in fluoride media via sol–gel technique using TritonX 100 and Tween-20. The surface area and pore volume of the MSN particles were modified by varying the concentration of Tween-20. The prepared MSN nanoparticles with large surface area and pore volume (T-2, T-3) were selected to accommodate the model drug duloxetine hydrochloride (DX) for evaluation of their drug-loading and release abilities. Calcined and DX loaded nanoparticles were characterized by Brunauer–Emmett–Teller technique (BET), powder X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric (TG) analysis and UV-diffuse reflectance (UV-DRS). In vitro release studies proved that the particle displays an initial burst release followed by sustained release for up to 140 h. From the studies it is evident that the synthesized particle may be useful as a carrier for sustained release of active pharmaceutical ingredients (APIs).

The microstructures and growth process characteristics of spherical Ni(OH)2 particles synthesized by the aqueous precipitation-crystallization method were investigated by SEM, TEM and XRD, and their growth mechanism was discussed. With the reaction beginning and continuing, amorphous Ni(OH)2 nano-crystallites grow up to spherical micron-particles with radially arranged crystallites. The nucleation, crystallization and re-crystallization led by Ostwald ripening simultaneously take place through the whole growth processes. With the course from reversible aggregation to irreversible agglomeration, the Ni(OH)2 particles tend to grow according to the template growth model: the growth on the crystallite templates stretching in the radius directions is free and quick, while the growth rate for crystallites in other directions is confined due to lower monomers concentration and tends to dissolve. So it is only the radially arranged crystallites that predominate in the particle and lead to characteristic microstructures.

The effect of the forced longitudinal ventilation on the heat release rate of tunnel fires is quantitatively analyzed and experimentally examined using the experimental data by Roh et al. (2007) . Results indicate that the relative increment of tunnel fire heat release rates varies proportionally with the quantity uS/(g1/2r5/2) that represents the relative value of the longitudinal air volumetric flow rate to the mass loss rate of the fire source.

This paper studied the control strategy for fuel injection impulse width based on an electronic fuel injection (EFI) motorcycle engine 156FMI. The basic fuel injection impulse width and correcting factors were calibrated by experiments. And it was gained the basic fuel injection impulse width MAP and series of correcting factors, including post start correction factor, warm-up correction factor, injection pressure correction factor, A/F closed-loop control correction factor, transient condition correction and battery voltage correction. The results show that the performance of power, fuel consumption and exhaust emission of electronic control engine developed are better than that of original carburetor engine, and the exhaust pollutant emissions of EFI motorcycle meet the requirements of Chinese Phase III emission standard.