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The control of the spin angular momentum of light plays an irreplaceable role in modern photon applications. In this work, we proposed a chiral metamaterial based on a bi-layer T-shaped structure. When circularly polarized light is incident along the normal direction (-z), the spin-selective transmissions and reflections occur in the mid-infrared frequency, which results in different transmittance and reflectance in quad-band frequencies. Here, the difference in transmittance (ΔT) values are 0.5, 0.4, 0.5, and 0.7, respectively. And the difference in reflectance (ΔR) reaches up to 0.4, 0.3, 0.4, and 0.5, respectively. Due to the chirality of the structure, the resulting circular dichroism (CD) is close to 0.2. In addition, the frequency and amplitude of the quad-band spin selections can be easily manipulated by rotating the rotation angle θ. Finally, we found that the similar spin-selective transmission and reflection can be achieved in Gigahertz (GHz) and Terahertz (THz) wavebands. The metamaterial might promote the application and development of versatile photonic devices.

In this work, we propose a dual-band optical diode based on a bilayer T-shaped metamaterial. This optical diode can conveniently convert the x-polarized wave to y-polarized one at about 106 THz and convert the y-polarized to x-polarized wave at around 163 THz when linearly polarized waves impinge on the sample under a forward normal incidence (+z direction). The dual-band polarization conversion ratios can reach up to 99.9 % and 99.6 % at 106 and 163 THz, respectively. In addition, the bi-layer metamaterial works as an optical diode located around the frequencies 106 and 163 THz, i.e. the x- and y-polarized plane waves can pass through the metamaterial in the forward direction, however, they are prevented from backward. The maximum asymmetric transmission parameters are 0.46 and 0.50. At last, both the ratios and bandwidth of dual-band cross-polarization conversion can be conveniently manipulated by the rotation angle θ. This proposed dual-band polarization conversions and optical diode may have promising applications in optical nano-devices, such as optical switches and polarization converters.

To eliminate the undesired terahertz (THz) interference and echo, broadband and tunable THz absorbing devices are urgently needed. Herein, we report a simple method to obtain an active THz absorption performance by ethanol-treated carbon nanotube sponges (CNT-Sponges). Firstly, the single CNT-Sponges show a high electromagnetic interference shielding effectiveness (EMI SE >40 dB), of which >80 % electromagnetic energy can be absorbed from 0.2 THz to 1.0 THz (98 % absorptivity at 1THz). Secondly, after spraying ethanol on CNT-Sponges (ECNT-Sponges), ECNT-Sponges present high reflection and a significant decrease in absorption and then undergo a recovery process with the change of ethanol content over time. The maximum absorption modulation efficiency is ∼40 %, and its tunable absorption mechanism has been explained: 1, the sprayed ethanol forms a protective film on the surface of CNT-Sponges, and then increases the surface reflection; 2, ethanol makes CNT-Sponges shrink and denser and then blocks the transmitted THz waves. Without complex element doping or outfields manipulation, this work provides a feasible way for broadband and tunable THz absorption.

Pithecellobium clypearia (Jack) Benth. 1844 belongs to the genus Pithecellobium in the family Fabaceae. The complete chloroplast genome of P. clypearia was sequenced and analyzed by Illumina sequencing in this study. The full length of the complete chloroplast genome is 176,770 bp, containing a pair of inverted repeat regions of 39,693 bp (IRa and IRb) separated by a large single-copy (LSC) region of 92,500 bp and a small single-copy (SSC) region of 4,884 bp. The P. clypearia chloroplast genome encodes 137 genes, comprising 92 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. Phylogenetic analysis based on complete chloroplast genomes revealed that P. clypearia is closely related to Archidendron lucyi and Pithecellobium flexicaule. This study provides useful resources for further study and development of this species.

Clerodendrum japonicum (Thunb.) Sweet belongs to the genus Clerodendrum in the family Lamiaceae. It is an important medicinal plant with great ornamental and economic value. We sequenced and analyzed the complete chloroplast genome of C. japonicum by Illumina sequencing in this study. The full length of the complete chloroplast genome is 152,215 bp, containing a pair of inverted repeat regions of 25,705 bp (IRa and IRb) separated by a large single-copy region (LSC) of 83,491 bp and a small single-copy region (SSC) of 17,314 bp. The C. japonicum chloroplast genome encodes 131 genes, comprising 85 protein-coding genes, 37 tRNA genes, 8 rRNA genes, and 1 pseudogene. This study will be useful for further study on population, phylogenetic, and molecular genetic studies of this medicinal plant.

Torenia fournieri belongs to the genus Torenia in the family Linderniaceae. The complete chloroplast genome of T. fournieri was sequenced and analyzed by Illumina sequencing in this study. The full length of the complete chloroplast genome is 153,938 bp, containing a pair of inverted repeat regions of 24,805 bp (IRa and IRb) separated by a large single copy region (LSC) of 85,498 bp and a small single copy region (SSC) of 18,830 bp. The T. fournieri chloroplast genome encodes 131 genes, comprising 87 protein-coding genes, 36 tRNA genes, 8 rRNA genes, without pseudogene. Phylogenetic analysis showed that T. fournieri was closely related to T. benthamiana and T. concolor within the genus Torenia in family Linderniaceae.

Objective We aimed to explore the effect of individualized medical nutrition guidance on pregnancy outcomes among older pregnant women. Methods This was a prospective study using a randomized controlled trial design. We selected 820 older pregnant women and randomly divided them into a study group and control group (410 women each). The control group was given routine health education and nutrition guidance; the study group was provided individualized medical nutrition guidance. Gestational diabetes mellitus, hypertensive disorders of pregnancy, vaginal delivery rate, postpartum hemorrhage rate, gestational body weight, neonatal birth weight, and neonate transfer to the neonatal intensive care unit (NICU) were compared between the groups. Results The incidence of gestational diabetes in the study group was significantly lower and the rate of vaginal delivery was significantly higher than those in the control group. The incidence of macrosomia, rate of neonatal transfer to the NICU, and rate of neonatal hyperbilirubinemia were significantly lower in the study group than those in the control group. Conclusions Individualized nutritional intervention for older pregnant women can effectively reduce the incidence of complications during pregnancy and childbirth and improve maternal and child outcomes.

Central to cellular proliferative, survival, and metabolic responses is the serine/threonine kinase mTOR, which is activated in many human cancers. mTOR is present in distinct complexes that are either modulated by AKT (mTORC1) or are upstream and regulatory of it (mTORC2). Governance of mTORC2 activity is poorly understood. Here, we report a transmembrane molecule in hematopoietic progenitor cells that physically interacts with and inhibits RICTOR, an essential component of mTORC2. Upstream of mTORC2 (UT2) negatively regulates mTORC2 enzymatic activity, reducing AKTS473, PKCα, and NDRG1 phosphorylation and increasing FOXO transcriptional activity in an mTORC2-dependent manner. Modulating UT2 levels altered animal survival in a T cell acute lymphoid leukemia (T-ALL) model that is known to be mTORC2 sensitive. These studies identify an inhibitory component upstream of mTORC2 in hematopoietic cells that can reduce mortality from NOTCH-induced T-ALL. A transmembrane inhibitor of mTORC2 may provide an attractive target to affect this critical cell regulatory pathway.

A chiral metallic metastructure composed of bilayer twisted bars is proposed to realize a broadband asymmetric transmission for linearly and circularly polarized incident light, aimed at sustaining high efficiency of unidirectional polarization conversion over the whole operation band. Such a one-way propagation results from the chiral structural arrangement that destroys the rotational and translational symmetries in all directions. Moreover, its ultra-broad bandwidth, mainly depending on the bar length, originates from the subwavelength plasmon coupling between long- and shortbar dipole-like responses. The efficient broadband one-way characteristic exhibits a structure with promising prospects for metadevices capable of unidirectional polarization conversion manipulation. [ABSTRACT FROM AUTHOR]

Polarization control of the light can be realized by ultrathin plasmonic structures, which is generally based on the effect of extraordinary optical transmission. In this paper, we designed a U-shaped plasmon-induced transparent metasurface to investigate the polarization state conversions of resonantly transmitted light through reducing the structural symmetry by rotation. A significant optical polarization conversion capability is found for impinging light with linear as well as circular polarization. In particular, the different polarization conversions between the left-handed and right-handed circular lights manifest the characteristic of circular dichroism. The results are useful for the potential applications such as a broadband quarter-wave plate. [ABSTRACT FROM AUTHOR]

Background: Toxoplasma gondii is an intracellular protozoan that can infect humans and other animals, including cattle. Cattle are one of the world's main sources of meat, and people who consume raw or undercooked meat and milk of cattle infected with T. gondii can become infected. In this study, a total of 5292 dairy cattle serum samples, collected from 17 cities (Henan Province, China) from January 2015 to September 2017, were screened for antibodies against T. gondii. Results: Antibodies to T. gondii were found in 1.93% (102/5292) (95% CI, 1.56-2.30) of dairy cattle using a modified agglutination test (cut-off 1:100). The results showed that geographic location and season may be risk factors for T. gondii infection of cattle (P < 0.05), and the seroprevalence of T. gondii in cattle along the Yellow River is higher than other areas. Conclusions: This is the first large-scale investigation on the seroprevalence of T. gondii infection in cattle from Central China. This survey shows that the T. gondii infection rate of dairy cattle is low; however, these findings provide additional information on the epidemiology of Chinese T. gondii. The possibility of dairy cattle exposure to T. gondii in Central China can not be ignored, and the consumption of raw or undercooked beef or milk may pose a risk to human health. [ABSTRACT FROM AUTHOR]

Regulation of STAT3 activation is critical for normal and malignant hematopoietic cell proliferation. Here, we have reported that the endogenous transmembrane protein upstream-of-mTORC2 (UT2) negatively regulates activation of STAT3. Specifically, we determined that UT2 interacts directly with GP130 and inhibits phosphorylation of STAT3 on tyrosine 705 (STAT3Y705). This reduces cytokine signaling including IL6 that is implicated in multiple myeloma and other hematopoietic malignancies. Modulation of UT2 resulted in inverse effects on animal survival in myeloma models. Samples from multiple myeloma patients also revealed a decreased copy number of UT2 and decreased expression of UT2 in genomic and transcriptomic analyses, respectively. Together, these studies identify a transmembrane protein that functions to negatively regulate cytokine signaling through GP130 and pSTAT3Y705 and is molecularly and mechanistically distinct from the suppressors of cytokine signaling (SOCS) family of genes. Moreover, this work provides evidence that perturbations of this activation-dampening molecule participate in hematologic malignancies and may serve as a key determinant of multiple myeloma pathophysiology. UT2 is a negative regulator shared across STAT3 and mTORC2 signaling cascades, functioning as a tumor suppressor in hematologic malignancies driven by those pathways. [ABSTRACT FROM AUTHOR]

Background: Transcutaneous acupoint electrical stimulation (TAES) as a needleless acupuncture has the same effect like traditional manual acupuncture. The combination of TAES and anesthesia has been proved valid in enhancing the anesthetic effects but its mechanisms are still not clear. Methods: In this study, we investigated the effect of TAES on anesthesia with an electroencephalogram (EEG) oscillation analysis on surgery patients anesthetized with propofol, a widely-used anesthetic in clinical practice. EEG was continuously recorded during light and deep propofol sedation (target-controlled infusion set at 1.0 and 3.0 µg/mL) in ten surgery patients with pituitary tumor excision. Each concentration of propofol was maintained for 6 min and TAES was given at 2-4 min. The changes in EEG power spectrum at different frequency bands (delta, theta, alpha, beta, and gamma) and the coherence of different EEG channels were analyzed. Results: Our result showed that, after TAES application, the EEG power increased at alpha and beta bands in light sedation of propofol, but reduced at delta and beta bands in deep propofol sedation (p < 0.001). In addition, the EEG oscillation analysis showed an enhancement of synchronization at low frequencies and a decline in synchronization at high frequencies between different EEG channels in either light or deep propofol sedation. Conclusions: Our study showed evidence suggested that TAES may have different effects on propofol under light and deep sedation. TAES could enhance the sedative effect of propofol at low concentration but reduce the sedative effect of propofol at high concentration. [ABSTRACT FROM AUTHOR]

Autoreactive B cells are regulated in the BM during development through mechanisms, including editing of the B cell receptor (BCR), clonal deletion, and anergy. Peripheral B cell tolerance is also important for protection from autoimmune damage, although the mechanisms are less well defined. Here we demonstrated, using a mouse model of SLE-like serology, that during an autoimmune response, RAG was reinduced in antigen-activated early memory or preplasma B cells. Expression of RAG was specific to antigen-reactive B cells, required the function of the IL-7 receptor (IL-7R), and contributed to maintenance of humoral tolerance. We also showed that soluble antigen could diminish a non-autoreactive antibody response through induction of BCR revision. These data suggest that tolerance induction operates in B cells at a postactivation checkpoint and that BCR revision helps regulate autoreactivity generated during an ongoing immune response. [ABSTRACT FROM AUTHOR]

We present a new kind of perfect absorber which roots in a toroidal dipole resonance. The toroidal metastructure consists of a metallic circular groove with a depth asymmetry, which couples to the toroidal dipole field in the near-infrared region and thus realizes nearly unit absorbance, acting as a perfect absorber. Moreover, this absorber owns a high sensitivity of 609.6 nm/RIU to the dielectric surroundings. Furthermore, by tuning the geometric parameters, both the toroidal dipole resonance and perfect absorbance characteristics are insensitive to the circular groove width, providing profound fabrication tolerance in future experiments. [ABSTRACT FROM AUTHOR]

The interference between toroidal and electric dipoles in the optical regime is investigated in a metallic composite metastructure composed of a 12-fold double-bar and an upright rod. It shows that toroidal and electric dipoles can be simultaneously excited, exhibiting a plasmon analog of electromagnetically induced transparency (EIT) and suppressing the far-field radiation. By shifting the upright rod transversally, another transparency window emerges due to the asymmetry of the geometry, resulting in dual-band EIT-like behavior. The result not only contributes to the understanding of optical toroidal dipoles, but also creates the possibility of designing optical devices based on the dual-band EIT-like effect. [ABSTRACT FROM AUTHOR]

We demonstrate the optical activity for linear polarization by twisting cascading multilayer nanobars, for which the x- (y-)polarized light is significantly transformed to a y- (x-)polarized one with enhanced transmittance in a unidirectional manner, and the bandwidth can be broadened by increasing the cascading number of layers. The polarization conversion rate reaches nearly 100% with a maximum cross-polarization transmission coefficient larger than 0.95. This phenomenon is attributed to the chiral structural arrangement and anisotropic resonance of nanobars, which consequently leads to different cross-polarization conversions between forward and backward incident lights, and thus the unidirectional transmission with an extinction ratio up to 103. These characteristics show application potential in optical nano-devices. [ABSTRACT FROM AUTHOR]

The obvious circular dichroism (CD) and optical activity can be obtained based on the chiral metamaterial due to the plasmon-enhanced effect, which is very attractive for future compact devices with enhanced capabilities of light manipulation. In this paper, we propose a dual-chiral metamaterial composed of bilayer asymmetric split ring resonators (ASRR) that are in mirror-symmetry shape. It is demonstrated that the CD can get enhancement in the terahertz regime. Moreover, the CD can be further improved by modulating the asymmetry of ASRR. The enhanced CD effect in the terahertz regime has great potential applications in sensing, biomedical imaging, and molecular recognition. [ABSTRACT FROM AUTHOR]

We demonstrate numerically and experimentally an efficient broadband asymmetric transmission (AT) by bilayer cross-shaped metamaterials for linearly polarized plane waves, attributed to a huge conversion capability between the cross polarizations. Physically, the phenomenon of AT results from the symmetry-broken geometry in this metamaterial. Due to the interaction of long and short-arm resonances of the twisted crosses, the AT bandwidth can be up to of the central wavelength, corresponding to a maximum cross-polarization conversion rate of . In particular, the broad bandwidth can be manipulated by the short-arm length, which produces an opportunity in designing a polarization-based spectral filter or other microwave devices. [ABSTRACT FROM AUTHOR]

A highly dispersive Fe/ZSM-5 as the precursor of Fe-S/ZSM-5 was prepared by decomposing Fe(CO)5 onto ZSM-5 zeolite at 250°C. Shengli lignite (SL) was isolated to extractable portion (EP) and extraction residue (ER) by exhaustive extraction with isometric carbon disulfide/acetone mixed solvent (IMCDSAMS) under ultrasonic irradiation. The EP and ER were analyzed with a direct analysis in real time ionization source coupled to ion trap mass spectrometer. Both of them and SL were analyzed with a Fourier transform infrared spectrometer. The ER was subjected to non-catalytic hydroconversion (NCHC) and catalytic hydroconversion (CHC) over Fe-S/ZSM-5, which was formed by in situ reaction of Fe/ZSM-5 with sulfur added, in cyclohexane under pressurized hydrogen at 300°C. The reaction mixtures were sequentially extracted with petroleum ether, carbon disulfide, methanol, acetone, and IMCDSAMS to afford extracts 1-5 (E1-E5), which were analyzed with a gas chromatography/mass spectrometer (GC/MS). As model reactions, the CHCs of di(1-naphthyl)methane (DNM) and diphenylmethane (DPM) over Fe-S/ZSM-5 were also conducted in cyclohexane at 300°C. The results show that more than 50% of organic matter in the ER was converted to a soluble portion by the CHC, whereas the yield of soluble portion from the NCHC is only 10.52%. GC/MS-detectable species only appear in the E1, which mainly consists of alkanes, arenes, and arenols either from the NCHC or from the CHC. DNM was selectively hydrocracked to naphthalene and 1-methylnaphthalene over Fe-S/ZSM-5, while DPM hydrocracking did not proceed, indicating that Fe-S/ZSM-5 catalyzed the formation of radical hydrogen from molecular hydrogen and subsequent radical hydrogen transfer (RHT) to the ipso-position of naphthalene ring in DNM. Some CH2 and O in the ER could be connected to condensed aromatic rings (CARs). Analogously, RHT to the ipso-position of CARs in the ER resulted in the release of arenes and phenols from the ER. [ABSTRACT FROM AUTHOR]

Three catalysts were prepared by impregnating the same volume of pentachloroantimony (PCA), trimethylsilyl trifluoromethanesulfonate (TMSTFMS), or isometric PCA and TMSTFMA into an activated carbon (AC). Di(1-naphthyl)methane (DNM) was used as a coal-related model compound to evaluate their catalytic activity. The results show that Car一Calk bond in DNM can be specifically cleaved over each catalyst to afford naphthalene and 1-methylnaphthalene under pressurized hydrogen at temperatures up to 300°C, but as a new solid acid (NSA), PCA–TMSTFMS/AC is significantly more active for DNM hydrocracking than the other two catalysts. FTIR and SEM analyses reveal the strong interactions among PCA, TMSTFMS, and the AC in the NSA. NH3-TPD analysis suggests that the NSA should exhibit appreciably stronger acidity than the other two catalysts. The strong interactions may result in the appreciably stronger acidity of the NSA than that of the other two catalysts and thereby facilitate DNM hydrocracking. It is presumed that H2 was heterolytically cleaved to immobile H− and mobile H+. The addition of mobile H+ to ipso-position of DNM should be crucial step for DNM hydrocracking. [Copyright &y& Elsevier]