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A magnetic dipole quasi-Yagi antenna based on a dielectric resonator (DR) is proposed in this letter. The dominate TE1δ1 mode of the rectangular DR is used as a magnetic dipole which can be differentially fed by the coplanar strip line (CPS). Thanks to the DR employment, the proposed antenna has several advantages such as compact size and flexible design which means the 3-D dimensions of the DR can be easily adjusted to cater for various applications. Meanwhile, the gain of the proposed DR quasi-Yagi antenna is higher than that of traditional electric dipole counterparts. Furthermore, since the DR driver is horizontally polarized, both the metal strip and DR can be used as a director for enhancing the end-fire gain. To verify the design concept, a prototype operating at the X-band is fabricated and measured. Good agreement between the simulated and measured results can be observed.
To explore whether and how group cognitive-behavioural therapy (GCBT) plus medication differs from medication alone for the treatment of generalised anxiety disorder (GAD).
Hundred and seventy patients were randomly assigned to the GCBT plus duloxetine (n=89) or duloxetine group (n=81). The primary outcomes were Hamilton Anxiety Scale (HAMA) response and remission rates. The explorative secondary measures included score reductions from baseline in the HAMA total, psychic, and somatic anxiety subscales (HAMA-PA, HAMA-SA), the Hamilton Depression Scale, the Severity Subscale of Clinical Global Impression Scale, Global Assessment of Functioning, and the 12-item Short-Form Health Survey. Assessments were conducted at baseline, 4-week, 8-week, and 3-month follow-up.
At 4 weeks, HAMA response (GCBT group 57.0% vs. control group 24.4%, p=0.000, Cohen’s d=0.90) and remission rates (GCBT group 21.5% vs. control group 6.2%, p=0.004; d=0.51), and most secondary outcomes (all p<0.05, d=0.36−0.77) showed that the combined therapy was superior. At 8 weeks, all the primary and secondary significant differences found at 4 weeks were maintained with smaller effect sizes (p<0.05, d=0.32−0.48). At 3-month follow-up, the combined therapy was only significantly superior in the HAMA total (p<0.045, d=0.43) and HAMA-PA score reductions (p<0.001, d=0.77). Logistic regression showed superiority of the combined therapy for HAMA response rates [odds ratio (OR)=2.12, 95% confidence interval (CI) 1.02−4.42, p=0.04] and remission rates (OR=2.80, 95% CI 1.27−6.16, p=0.01).
Compared with duloxetine alone, GCBT plus duloxetine showed significant treatment response for GAD over a shorter period of time, particularly for psychic anxiety symptoms, which may suggest that GCBT was effective in changing cognitive style.
Seed reserves play vital roles in seed germination and seedling growth and their variation may be related to various environment factors, plant traits and phylogenetic history. Here, the evolutionary correlation associated with seed mass and altitude and carbon (C), nitrogen (N) and phosphorus (P) allocation of seeds among 253 alpine herbaceous plants was tested. In this study, phylogeny had strong limitations on nutrient allocation of seeds across species, and species from younger phylogenetic groups tended to have higher N and P contents, which might be considered as the evolutionary selection of seed plants. Higher seed N and P content would help seedlings to gain more survival chance and stronger competitive capacity, and their progeny would be more likely to be preserved. When phylogeny was considered, altitude only had a significant positive effect on P content, but the negative effects on seed mass were all expressed. The independent effects of altitude and seed mass suggest that the nutrient allocation of seeds might be affected by both environment and plant traits. In addition, altitude and seed mass displayed partial overlapping effects on nutrient allocation of seeds. The negative effects of seed mass were affected slightly by altitude, whereas altitude only had a significant positive effect on P content when seed mass was controlled. Above all, seed P content showed obvious and general correlations with seed mass, altitude and age of clade, which indicated that higher seed P content might be an adaptive selection of species associated with growth and survival of progeny.
In a general equilibrium framework, this paper studies the properties, in terms of labour market distortions and capital accumulation, of three social security systems: a pay-as-you-go notional defined contribution (PAYG NDC), a fully funded (FF), and a novel modified FF (MFF) system, which includes an intragenerational redistributive component to guarantee minimum living standards to future low-income retirees. We show that while PAYG NDC depresses labour supply and physical capital accumulation, FF is neutral on both dimensions. Conversely, MFF slightly increases physical capital accumulation, without significantly reducing labour supply incentives. Moreover, it reduces the burden of future intergenerational redistribution, and increases social welfare.
We examined the in vitro developmental competence of parthenogenetic activation (PA) oocytes activated by an electric pulse (EP) and treated with various concentrations of AZD5438 for 4 h. Treatment with 10 µM AZD5438 for 4 h significantly improved the blastocyst formation rate of PA oocytes in comparison with 0, 20, or 50 µM AZD5438 treatment (46.4% vs. 34.5%, 32.3%, and 24.0%, respectively; P < 0.05). The blastocyst formation rate was higher in the group treated with AZD5438 for 4 h than in the groups treated with AZD5438 for 2 or 6 h (42.8% vs. 38.6% and 37.2%, respectively; P > 0.05). Furthermore, 66.67% of blastocysts derived from these AZD5438-treated PA oocytes had a diploid karyotype. The blastocyst formation rate of PA and somatic cell nuclear transfer (SCNT) embryos was similar between oocytes activated by an EP and treated with 2 mM 6-dimethylaminopurine for 4 h and those activated by an EP and treated with 10 µM AZD5438 for 4 h (11.11% vs. 13.40%, P > 0.05). In addition, the level of maturation-promoting factor (MPF) was significantly decreased in oocytes activated by an EP and treated with 10 µM AZD5438 for 4 h. Finally, the mRNA expression levels of apoptosis-related genes (Bax and Bcl-2) and pluripotency-related genes (Oct4, Nanog, and Sox2) were checked by RT-PCR; however, there were no differences between the AZD5438-treated and non-treated control groups. Our results demonstrate that porcine oocyte activation via an EP in combination with AZD5438 treatment can lead to a high blastocyst formation rate in PA and SCNT experiments.
In this paper, a tri-band bandpass filter (BPF) using asymmetric stub-loaded stepped-impedance resonator (SL-SIR) is presented. The asymmetric characteristic of SL-SIR broadens degrees of freedom for three controllable modes design. Also, the coupling coefficients (Mij) and the external quality factors (Qei) at each passband of the filter can be independently adjusted by the proposed mixed-type feedline structure. Besides, multi-transmission zeros are produced to improve the isolation and selectivity of the passbands. Finally, a tri-band BPF is operated at 1.9 GHz (time division long term evolution – TD-LTE band), 3.2 GHz (worldwide interoperability for microwave access – WiMAX band), and 5.8 GHz (wireless local area networks – WLAN band) and their insertion loss are 1.03, 0.94, and 1.27 dB, respectively. The measured results of the fabricated tri-band BPF exhibit good agreement with simulated results.
Cerebral small vessel disease (SVD) is the common cause of cognitive decline in the old population. MRI can be used to clarify its mechanisms. However, the surrogate markers of MRI for early cognitive impairment in SVD remain uncertain to date. We investigated the cognitive impacts of cerebral microbleeds (CMBs), diffusion tensor imaging (DTI), and brain volumetric measurements in a cohort of post-stroke non-dementia SVD patients.
Fifty five non-dementia SVD patients were consecutively recruited and categorized into two groups as no cognitive impairment (NCI) (n = 23) or vascular mild cognitive impairment (VaMCI) (n = 32). Detailed neuropsychological assessment and multimodal MRI were completed.
The two groups differed significantly on Z scores of all cognitive domains (all p < 0.01) except for the language. There were more patients with hypertension (p = 0.038) or depression (p = 0.019) in the VaMCI than those in the NCI group. Multiple regression analysis of cognition showed periventricular mean diffusivity (MD) (β = −0.457, p < 0.01) and deep CMBs numbers (β = −0.352, p < 0.01) as the predictors of attention/executive function, which explained 45.2% of the total variance. Periventricular MD was the independent predictor for either memory (β = −0.314, p < 0.05) or visuo-spatial function (β = −0.375, p < 0.01); however, only small proportion of variance could be accounted for (9.8% and 12.4%, respectively). Language was not found to be correlated with any of the MRI parameters. No correlation was found between brain atrophic indices and any of the cognitive measures.
Arteriosclerotic CMBs and periventricular white matter disintegrity seem to be independent MRI surrogated markers in the early stage of cognitive impairment in SVD.
The strain hardening effect and dynamic recovery behavior of a Ni-based superalloy are studied by isothermal compressive tests. A new unified dislocation-density based constitutive model is developed to characterize the strain hardening effect and dynamic recovery behavior of the studied superalloy. In the developed constitutive model, some material parameters (yield stress, strain hardening coefficient, and dynamic recovery coefficient) are assumed as functions of initial grain size, deformation temperature, and strain rate. An iterative algorithm is designed to predict the high-temperature deformation behaviors under time-variant hot working conditions. The hot deformation parameters and material parameters can be updated in each strain increment. Comparisons between the experimental and calculated flow stresses indicate that the developed constitutive model can accurately describe the high-temperature deformation behavior of the studied superalloy. Furthermore, the developed constitutive model is also successfully used for analyzing time-variant hot working processes.
The long-term outcome of never-treated patients with schizophrenia is
To compare the 14-year outcomes of never-treated and treated patients
with schizophrenia and to establish predictors for never being
All participants with schizophrenia (n = 510) in Xinjin,
Chengdu, China were identified in an epidemiological investigation of 123
572 people and followed up from 1994 to 2008.
The results showed that there were 30.6%, 25.0% and 20.4% of patients who
received no antipsychotic medication in 1994, 2004 and 2008 respectively.
Compared with treated patients, those who were never treated in 2008 were
significantly older, had significantly fewer family members, had higher
rates of homelessness, death from other causes, being unmarried, living
alone, being without a caregiver and poor family attitudes. Partial and
complete remission in treated patients (57.3%) was significantly higher
than that in the never-treated group (29.8%). Predictors of being in the
never-treated group in 2008 encompassed baseline never-treated status,
being without a caregiver and poor mental health status in 1994.
Many patients with schizophrenia still do not receive antipsychotic
medication in rural areas of China. The 14-year follow-up showed that
outcomes for the untreated group were worse. Community-based mental
healthcare, health insurance and family intervention are crucial for
earlier diagnosis, treatment and rehabilitation in the community.
Nanogenerators (NGs) have great potential to solve the problems of energy depletion and environmental pollution. Here, two types of flexible nanogenerators (FNGs) based on graphene oxide (GO) and multiwall carbon nanotubes (MW-CNTs) are presented. The peak output voltage and current of GO based FNG reached up to 2 V and 30 nA, respectively, under 15 N force at 1 Hz. Moreover, the output voltage could be improved to 34.4 V when the frequency was increased to 10 Hz. It was also found the output voltage increased from 0.1 V to 2.0 V using a released GO structure. The other FNG was made by MW-CNTs mixed with ZnO nanoparticles (NPs). Its output voltage and power reached up to 7.5 V and 18.75 mW, respectively, which is much larger than that of bare ZnO based FNG. Furthermore, a peak voltage of 30 V could be gained by stamping one’s foot on the FNG. Finally, a modified NG was fabricated using four springs and two flexible layers. As a result, the voltage and power reached up to 9 V and 27mW, respectively. These works may bring out broad applications in energy harvesting.
The role of oxidative stress in skeletal health is unclear. The present study investigated whether a high dietary intake of antioxidant nutrients (vitamins C and E, β-carotene, animal-derived vitamin A, retinol equivalents, Zn and Se) is associated with a reduced risk of hip fracture in elderly Chinese. This 1:1 matched case–control study involved 726 elderly Chinese with hip fracture and 726 control subjects, recruited between June 2009 and May 2013. Face-to-face interviews were conducted to determine habitual dietary intakes of the above-mentioned seven nutrients based on a seventy-nine-item FFQ and information on various covariates, and an antioxidant score was calculated. After adjustment for potential covariates, dose-dependent inverse associations were observed between the dietary intake of vitamin C, vitamin E, β-carotene, and Se and antioxidant score and the risk of hip fracture (P for trend ≤ 0·005). The OR of hip fracture for the highest (v. lowest) quartile of intake were 0·39 (95 % CI 0·28, 0·56) for vitamin C, 0·23 (95 % CI 0·16, 0·33) for vitamin E, 0·51 (95 % CI 0·36, 0·73) for β-carotene, 0·43 (95 % CI 0·26, 0·70) for Se and 0·24 (95 % CI 0·17, 0·36) for the antioxidant score. A moderate-to-high dietary intake of retinol equivalents in quartiles 2–4 (v. 1) was found to be associated with a lower risk of hip fracture (OR range: 0·51–0·63, P< 0·05). No significant association was observed between dietary Zn or animal-derived vitamin A intake and hip fracture risk (P for trend >0·20). In conclusion, a higher dietary intake of vitamins C and E, β-carotene, and Se and a moderate-to-high dietary intake of retinol equivalents are associated with a lower risk of hip fracture in elderly Chinese.
We associate the topological entropy of monotone recurrence relations with the Aubry–Mather theory. If there exists an interval
such that, for each
, all Birkhoff minimizers with rotation number
do not form a foliation, then the diffeomorphism on the high-dimensional cylinder defined via the monotone recurrence relation has positive topological entropy.
Numerical and theoretical investigations are carried out for the stability of the dust acoustic waves (DAWs) under the transverse perturbation in a two-ion temperature magnetized and collisionless dusty plasma. The Zakharov-Kuznetsov (ZK) equation, modified ZK equation, and Extended ZK (EZK) equation of the DAWs are given by using the reductive perturbation technique. The cut-off frequency is obtained by applying higher-order transverse perturbations to the soliton solution of the EZK equation. The propagation velocity of solitary waves, the real cut-off frequency, as well as the growth rate of the higher-order perturbation to the solitary wave are obtained.
The intensity of pupal diapause in the cotton bollworm, Helicoverpa armigera (Hübner) was investigated under both laboratory and natural conditions. By transferring diapausing pupae induced under LD 11:13, LD 12:12 and LD 13:11 at 20, 22 and 25 °C to 25 °C combined with LD 15:9 to terminate diapause the rearing day length of 11 h evoked greater intensity of diapause than did 12 and 13 h at 25 °C; whereas the rearing temperature of 25 °C evoked more intense diapause than did 20 and 22 °C under LD 11:13. By transferring diapausing pupae induced under LD 12:12 at 20 and 22 °C to six temperatures of 18, 20, 22, 25, 28 and 31 °C combined with LD 15:9 to terminate diapause, the duration of diapause was significantly shortened from 146 days at 18 °C to 24 days at 31 °C, showing that high temperatures significantly accelerate diapause development. Furthermore, the duration of diapause was significantly longer at the rearing temperature of 22 °C than that at 20 °C when the diapause-terminating temperatures were 20 and 22 °C. Chilling at 5 °C did not shorten the duration of diapause but lengthened it when chilling period was included. However, chilling plays an important role in synchronizing adult emergence. Rearing temperature of 22 °C also evoked more intense diapause than did 20 °C in most chilling treatments. When the overwintering pupae were transferred at different times from natural temperatures to 25 °C, it was found that the earlier the transfer took place, the earlier the adults emerged when the time spent under natural conditions was included. However, cool temperatures before March showed an enhanced effect on diapause development at 20 °C, suggesting that the high diapause-terminating temperature can offset the effect of chilling on diapause development. The result of diapause termination under natural conditions suggests that the developmental threshold for post-diapause development in H. armigera should be around 17.5 °C.
Vahid Sandoghdar, Max Planck Institute for the Science of Light and Friedrich-Alexander University, Erlangen-Nürnberg,
Mario Agio, National Institute of Optics (INO-CNR) and European Laboratory for Nonlinear Spectroscopy (LENS),
Xue-Wen Chen, Max Planck Institute for the Science of Light,
Stephan Götzinger, Friedrich-Alexander University, Erlangen-Nürnberg and Max Planck Institute for the Science of Light,
Kwang-Geol Lee, Max Planck Institute for the Science of Light
The atom is the most elementary constituent of any model that describes the quantum nature of light–matter interaction. Because atoms emit and absorb light at well-defined frequencies, nineteenth century scientists thought of them as collections of harmonically oscillating electric dipole moments or EHDs. In the language of modern physics, the latter represent dipolar transitions among the various quantum mechanical states of an atom.
In a strict definition, the field of quantum optics deals with problems that not only require the quantization of matter but also of the electromagnetic field, with examples such as (i) generation of squeezed light or Fock states, (ii) strong coupling of an atom and a photon, (iii) entanglement of a photon with an atom and (iv) Casimir and van der Waals forces. There are also many other important topics that have been discussed within the quantum optics community but do not necessarily require a full quantum electrodynamic (QED) treatment. Examples are (i) cooling and trapping of atoms, (ii) precision spectroscopy and (iii) modification of spontaneous emission.
The simple picture of a TLS as an EHD remains very insightful and valuable to this day. Indeed, much of what we discuss in this chapter has to do with the interplay between the quantum and classical mechanical characters of dipolar oscillators. For instance, the extinction cross-section of a TLS, given by 3λ2/2π, can be derived just as well using quantum mechanics  or classical optics . Another example, albeit more subtle, concerns the spontaneous emission rate.
The strategies of repair of tetralogy of Fallot change with the age of patients. In children older than 4 years and adults, the optimal strategy may be to use different method of reconstruction of the right ventricular outflow tract from those followed in younger children, so as to avoid, or reduce, the pulmonary insufficiency that is increasingly known to compromise right ventricular function.
From April, 2001, through May, 2008, we undertook complete repair in 312 patients, 180 male and 132 female, with a mean age of 11.3 years ±0.4 years, and a range from 4 to 48 years, with typical clinical and morphological features of tetralogy of Fallot, including 42 patients with the ventriculo-arterial connection of double outlet right ventricle. The operation was performed under moderate hypothermia using blood cardioplegia. The ventricular septal defect was closed with a Dacron patch. When it was considered necessary to resect the musculature within the right ventricular outflow tract, or perform pulmonary valvotomy, we sought to preserve the function of the pulmonary valve by protecting as far as possible the native leaflets, or creating a folded monocusp of autologous pericardium.
The repair was achieved completely through right atrium in 192, through the right ventricular outflow tract in 83, and through the right atrium, the outflow tract, and the pulmonary trunk in 36 patients. A transjunctional patch was inserted in 169 patients, non-valved in all but 9. There were no differences regarding the periods of aortic cross-clamping or cardiopulmonary bypass. Of the patients, 5 died (1.6%), with no influence noted for the transjunctional patch. Of those having a non-valved patch inserted, three-tenths had pulmonary regurgitation of various degree, while those having a valved patch had minimal pulmonary insufficiency and good right ventricular function postoperatively, this being maintained after follow-up of 8 to 24-months.
Based on our experience, we suggest that the current strategy of repair of tetralogy of Fallot in older children and adults should be based on minimizing the insertion of transjunctional patches, this being indicated only in those with very small ventriculo-pulmonary junctions. If such a patch is necessary, then steps should be taken to preserve the function of the pulmonary valve.
To increase our understanding of the relationships of trunk fat mass (FMtrunk) and four anthropometric indices in Chinese males, 1090 males aged 20–40 years were randomly recruited from the city of Changsha, China. Waist circumference (WC) and hip circumference (HC) were measured using standardized equipment, and three other anthropometric indices of BMI, waist:hip ratio (WHR) and conicity index (CoI) were calculated using weight, height, HC and WC. FMtrunk (in kg) was measured using a Hologic QDR 4500 W dual-energy X-ray absorptiometry scanner. There was an increasing trend of FMtrunk, %FMtrunk (percentage of FMtrunk) and BMI, WC, WHR, CoI in successively older age groups (e.g. the mean FMtrunk values were 4·63 (sd 2·58), 5·39 (sd 2·74), 5·93 (sd 2·82), 6·57 (sd 2·94) in four 5-year age groups, respectively). FMtrunk and %FMtrunk were significantly correlated with four anthropometric indices with the Pearson's correlation coefficients ranging from 0·25 to 0·86. Principal component analysis was performed to form three principal components that interpreted over 99·5% of the total variation of four related anthropometric indices in all age groups, with over 65% of the total variation accounted by principal component 1. Multiple regression analyses showed that three principal components explained a greater variance (R2 70·0–80·1%) in FMtrunk than did BMI or WC alone (R2 57·8–74·1%). The present results suggest that there is an increasing trend of FMtrunk and four anthropometric indices in successively older age groups; that age has important effects on the relationships of FMtrunk and studied anthropometric indices; and that the accuracy of predicting FMtrunk using four anthropometric indices is higher than using BMI or WC alone.
A new reliable embedded atom method potential for hydrogen in body-centered-cubic (bcc) iron is developed by fitting not only to the properties of hydrogen in a perfect bcc iron lattice but also to the properties of hydrogen binding to vacancies. The validity of the potential is examined by calculating the properties of hydrogen trap binding to surfaces and dislocations that are in good accordance with the experiments. A brief application of the potential by molecular dynamic simulation reveals that hydrogen accumulated ahead of the crack tip induces serious hydrogen embrittlement.
In this work, the surface properties of a DNA microarray formed on silicon based solid support are studied at different stages during the hybridization process. A modified immobilization process using the covalent immobilization of thiol-terminated DNA oligonucleotides on self-assembled layers of (3-mercaptopropyl) trimethoxysilane (MPTS) by disulfide bond formation is used to selectively attach DNA probes onto the surface of silicon dioxide. Contact angle measurement is used to monitor the bonding of MPTS on the surface. Atomic force microscopy (AFM) shows an increase in particle size before and after the growth of the MPTS layer. Fluorescence microscopy reveals the success of hybridization of complementary oligonucleotides labeled by FAM to the probe. The effects of modified immobilization process on other common material in silicon processing are also studied. As a result of the corrosive chemical used in the process, common metals used in micro-fabrication processes like aluminum are etched away. Silicon nitride is not affected by the immobilization and hybridization process, and thus can be used as a passivation and isolation material to conform the DNA to a specific area for DNA microarray to reduce cross-talk. The fluorescence image from the scanner indicates silicon nitride can effectively be used as an isolation material with linewidth down to 1 μm.
The optical and vibrational properties of small CdSe and CdS particles embedded in a glass matrix and as a colloid have been studied as a function of pressure up to 90 kbar using Raman scattering and photoluminescence techniques. We will discuss the use of high pressure optical spectroscopy techniques, where the sample is contained in a diamond anvil.cell with optical access, to study the nature of the electronic states in semiconductor nanocrystals. Raman scattering is employed to establish the enhanced pressure stability of the wurtzite phase in the II-VI nanocrystalline composites. Photolurninescence is used to study the energies of electronic states. The wurtzite to rocksalt phase transition behavior in the nanocrystallite systems is quite different from that in the bulk material. This different behavior is attributed to a large number of defects (vacancies) in the nanocrystallite system. This work demonstrates that the main defects in the CdS glass composites are cadmium vacancies; while in CdSe Selenium vacancies exist in the conduction band. The pressure dependence of the Huang-Rhys parameter, characteristic for the strength of the electron-phonon coupling, will also be discussed for the nanocrystalline samples versus the bulk material.