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In electromagnetism, dualities exist between time and space since they both contribute to the propagation of electromagnetic waves to some extent. Such dualities provide us with an alternative tool to manipulate the electromagnetic waves via temporal discontinuities in addition to spatially symmetry - breaking structures. In this work, we investigate the reflection and refraction of time-periodic structures, which can be regarded as a temporal analogy to the distributed Bragg reflector. The Fresnel-like coefficients are derived by imposing appropriate boundary conditions. It is suggested that such temporal modulated structures may pave the way for complementary manipulation of electromagnetic waves.

Neonatal jaundice is a common disease that affects up to 60% of newborns. Gut microbiota mediated the excretion of bilirubin from the human body. However, the relationship between early gut microbiome and development of neonatal jaundice is not fully understood. Here we sought to characterize meconium microbiome of newborns and to clarify its association with risk of neonatal jaundice.We conducted a nested case-control study with 301 newborns providing meconium samples from 2014 to 2015. The main outcome was the development of neonatal jaundice at 42 day follow-up. 16S rRNA gene sequencing was performed to profile the meconium microbiome. LEfSe was employed to identify different features between control and case groups. Logistic regression was used to estimate the risk effect of early gut microbiome on neonatal jaundice.Logistic regression models suggested that higher ɑ-diversity was significantly associated with lower risk of jaundice in cesarean infants (OR 0.72, 95% CI 0.52-0.98), but not in infants born naturally. Higher relative abundance of Bifidobacterium pseudolongum in newborn meconium was significantly associated with lower risk of jaundice both in cesarean-born infants and in the total subjects (OR 0.24, 95% CI 0.07-0.68; OR 0.55, 95% CI 0.31-0.95, respectively). Spearman's correlations showed that relative abundance of B. pseudolongum was significantly correlated with ɑ-diversity (P 0.01).Preventive and treatment methods implying early gut microbiome intervention could be promising for the management of neonatal jaundice.

Titanium dioxide nanoparticles (TiO2 NPs) exist in many nano-products and concerns have been raised about their potential toxicity on human beings. One such issue is their potential effects on placental function, and the studies on this topic are limited and the mechanism remains unclear. Here we employed human trophoblast HTR-8/SVneo cells to investigate the effects of TiO2 NPs on trophoblast. Results showed that TiO2 NPs could enter cells and were mostly distributed in lysosomes, with some in the cytoplasm. TiO2 NPs and protein aggregation were found in both fetal bovine serum (FBS) in culture medium and cytoplasm of HTR-8/SVneo cells. In consistence with that, proteostasis of HTR-8/SVneo cells was significantly disrupted and endoplasmic reticulum (ER) stress related markers including PERK, IRE1-α were increased. After high speed centrifugation, the proteins PERK and IRE1-α were dramatically decreased in the highest TiO2 NPs treatment group, which indicated interactions between TiO2 NPs and these two proteins. Meanwhile, the protein expressions of LC3-II/LC3-I and P62, the autophagy biomarkers, were increased and the autophagy flux was not blocked. Cellular ROS stress increased and mitophagy related genes including PINK and Parkin increased along with the increased co-localization of LC3 and mitochondria. Taken together, these results indicated that TiO2 NPs interacted with intracellular proteins and activated ER stress and mitophagy in HTR-8/SVneo cells, which might do damage to placental function.

Glial cell line‑derived neurotrophic factor (GDNF) is critical for the proliferation of spermatogonial stem cells (SSCs), but the underlying mechanisms remain poorly understood. In this study, an unbiased metabolomic analysis was performed to examine the metabolic modifications in SSCs following GDNF deprivation, and 11 metabolites were observed to decrease while three increased. Of the 11 decreased metabolites identified, glycylglycine was observed to significantly rescue the proliferation of the impaired SSCs, while no such effect was observed by adding sorbitol. However, the expression of self‑renewal genes, including B‑cell CLL/lymphoma 6 member B, ETS variant 5, GDNF family receptor α1 and early growth response protein 4 remained unaltered following glycylglycine treatment. This finding suggests that although glycylglycine serves an important role in the proliferation of SSCs, it is not required for the self‑renewal of SSCs.

Soil-transmitted helminth (STH) infections are a global health issue affecting nearly one-third of the world's population. As most endemic areas of STH are impoverished countries or regions with limited healthcare resources, the accurate diagnosis of STH requires analytical tools that are not only quantitative, but also portable, inexpensive, and with no or minimal demand for external instrument. Herein, we introduce a novel paper-based diagnostic device, termed quantitative paper-based DNA reader (qPDR), capable of quantifying STH at the molecular level by measuring distance as readout, thus eliminating the need for external readers. On the basis of the unique interfacial interaction of a DNA intercalating dye, SYBR Green I, with native cellulose on a chromatographic paper, qPDR allows the distance-based quantification of minute amounts of double-stranded DNA as short as 6 min. By integrating qPDR with polymerase chain reactions that were performed using a smartphone-controlled portable thermal cycler, we were able to quantify minute amount of genetic markers from adult worms of an STH (Trichuris trichiura) that were expelled post-treatment by infected children living in the rural areas of Honduras.

miRNAs and the primers used for qRT-PCR verification.

Background: The evaluation of the chemical impact on human health is usually constrained to the analysis of the health effects of exposure to a single chemical or a group of similar chemicals at one time. The effects of chemical mixtures are seldom analyzed. In this study, we applied three statistical models to assess the association between the exposure to a mixture of seven xenobiotics (three phthalate metabolites, two phenols, and two pesticides) and obesity. Methods: Urinary levels of environmental phenols, pesticides, and phthalate metabolites were measured in adults who participated in the U.S.-based National Health and Nutrition Examination Survey (NHANES) from 2013 to 2014. Body examination was conducted to determine obesity. We fitted multivariable models, using generalized linear (here both logistic and linear) regression, weighted quantile sum (WQS) regression, and Bayesian kernel machine regression (BKMR) models to estimate the association between chemical exposures and obesity. Results: Of 1269 individuals included in our final analysis, 38.5% had general obesity and 58.0% had abdominal obesity. In the logistic regression model established for each single chemical, bisphenol S (BPS), mono (carboxyoctyl) phthalate (MCOP), and mono (2-ethyl-5-carboxypentyl) phthalate (MECPP) were associated with both general and abdominal obesity (fourth vs. first quartile). In linear regression, MCOP was associated with BMI and waist circumference. In WQS regression analysis, the WQS index was significantly associated with both general obesity (OR = 1.63, 95% CI: 1.21–2.20) and abdominal obesity (OR = 1.66, 95% CI: 1.18–2.34). MCOP, bisphenol A (BPA), bisphenol S (BPS), and mono ethyl phthalate (MEP) were the most heavily weighing chemicals. In BKMR analysis, the overall effect of mixture was significantly associated with general obesity when all the chemicals were at their 60th percentile or above it, compared to all of them at their 50th percentile. MCOP, BPA, and BPS showed positive trends. By contrast, MECPP showed a flat and modest inverse trend. Conclusion: When comparing results from these three models, MCOP, BPA, and BPS were identified as the most important factors associated with obesity. We recommend estimating the joint effects of chemical mixtures by applying diverse statistical methods and interpreting their results together, considering their advantages and disadvantages. Keywords: Chemical mixture, Weighted quantile sum (WQS) regression, Bayesian kernel machine regression (BKMR), Obesity, Obesogen

MicroRNAs (miRNAs) are a class of single-stranded non-coding small RNAs (sRNAs) that are 20–24 nucleotides (nt) in length. Extensive studies have indicated that miRNAs play important roles in plant growth, development and stress responses. With more copper (Cu) and copper containing compounds used as bactericides and fungicides in plants, Cu stress has become one of the serious environmental problems that affect plant growth and development. In order to uncover the hidden response mechanisms of Cu stress, two small RNA libraries were constructed from Cu-treated and water-treated (Control) leaves of ‘Summer Black’ grapevine. Following high-throughput sequencing and filtering, a total of 158 known and 98 putative novel miRNAs were identified in the two libraries. Among these, 100 known and 47 novel miRNAs were identified as differentially expressed under Cu stress. Subsequently, the expression patterns of nine Cu-responsive miRNAs were validated by quantitative real-time PCR (qRT-PCR). There existed some consistency in expression levels of Cu-responsive miRNAs between high throughput sequencing and qRT-PCR assays. The targets prediction of miRNAs indicates that miRNA may regulate some transcription factors, including AP2, SBP, NAC, MYB and ARF during Cu stress. The target genes for two known and two novel miRNAs showed specific cleavage sites at the 10th and/or 11th nucleotide from the 5′-end of the miRNA corresponding to their miRNA complementary sequences. The findings will lay the foundation for exploring the role of the regulation of miRNAs in response to Cu stress and provide valuable gene information for breeding some Cu-tolerant grapevine cultivars.

In this paper, we propose a reference frame search method for JVET future video codec (FVC) that employs the quadtree plus binary tree (QTBT) structure. Among many new technologies proposed in FVC, QTBT poses a significant challenge since it contains the structural change of coding tree unit from HEVC. To reduce the encoding complexity of FVC with QTBT structure, we investigated some redundancy in motion estimation process—particularly, the reference frame search. In this paper, we present a method that effectively restricts the reference frame search range of general motion estimation as well as of affine motion estimation, exploiting the dependence within QTBT structure. The proposed method minimizes the maximum of the reference frame search ranges per each coding unit (CU) based on the prediction information of parents node. To be specific, the prediction direction and the index of reference frame of parent node were used. In addition, the proposed method utilizes the information of binary tree depth and of temporal layer to prevent undesired coding loss. The experimental results showed that the proposed method decreased the encoding time of motion estimation by 34% on average in comparison with joint exploration test model (JEM) 3.1, maintaining a reasonable coding efficiency (less than a 0.3% BD-rate loss).

Some large population-based cohort studies highlighted the risk of maternal smoking during pregnancy (MSDP) for children attention-deficit/hyperactivity disorder (ADHD). However, the causality of this association is still controversial. Here we performed a meta-analysis trying to clarify the association between prenatal exposure to MSDP and ADHD in offspring. After publication screening, 27 eligible original articles with a total of 3076173 subjects were included. The results showed that either prenatal exposure to MSDP or smoking cessation during first trimester was significantly associated with childhood ADHD after adjusting for parental psychiatric history and social socioeconomic status. Smoking cessation before pregnancy, which was not significantly associated with childhood ADHD, was strongly recommended for female smokers planning to conceive. Inconsistent results were obtained in the meta-analysis on the risk of maternal passive smoking during pregnancy caused by paternal smoking. We also found that risk of MSDP for childhood ADHD varied across geographic regions.

Both bisphenol A (BPA) and obesity affect male reproductive system. However, whether there is an interaction between them remains poorly understood. The aim of the present study was to evaluate the interaction between BPA exposure and obesity on semen quality and elucidate the mechanism in humans and animals. We firstly analyzed the interaction on semen volume, sperm count per ejaculate, sperm concentration and sperm motility in 357 men, and found that urinary BPA concentration was significantly correlated with sperm count per ejaculate in obese men (β=−34.62; 95% CI: −60.75, −8.48; P=0.01). Then we validated the interaction using lean and obese mice with administration of BPA. Significant interactions between BPA exposure and obesity on sperm count and sperm concentration was observed in mice. Finally, we conducted metabolomics analyses to identify metabolites related to the interaction. Metabolites related to the interaction, including capric acid, dodecanoic acid, l-palmitoylcarnitine, niacinamide, etc., are known to play critical roles in fatty acid oxidation and tricarboxylic acid cycle indicating increased oxidative stress associated with male reproductive dysfunction. Thus, our study finds an interaction between BPA exposure and obesity on sperm count and reveals potential metabolic mechanisms. It emphasizes the importance to study interactions between endocrine disrupting chemicals and obesity, and opens avenues for the possible use of animal models in identifying the interactions. Keywords: Obesity, Bisphenol A, Interaction, Semen quality, Metabolomics

Methamidophos is a representative organophosphate insecticide. The knowledge of its developmental neurotoxicity is limited, especially for zebrafish in the early stages of their life. Four hour post-fertilization (hpf) zebrafish embryos were exposed to several environmentally relevant concentrations of methamidophos (0, 25, and 500 μg/L) for up to 72 hpf. Locomotor behavior was then studied in the zebrafish larvae at this timepoint. Acridine orange (AO) staining was carried out in the zebrafish larvae, and the mRNA levels of genes associated with neural development (mbp and syn2a) were analyzed by reverse transcription-polymerase chain reaction (RT-PCR). The number of escape responders for mechanical stimulation was significantly decreased in exposed groups. AO staining showed noticeable signs of apoptosis mainly in the brain. In addition, the mRNA levels of mbp and syn2a were both significantly down-regulated in exposed groups. Our study provides the first evidence that methamidophos exposure can cause developmental neurotoxicity in the early stages of zebrafish life, which may be caused by the effect of methamidophos on neurodevelopmental genes and the activation of cell apoptosis in the brain.

MicroRNAs (miRNAs) are a class of single-stranded non-coding small RNAs (sRNAs) that are 20–24 nucleotides (nt) in length. Extensive studies have indicated that miRNAs play important roles in plant growth, development and stress responses. With more copper (Cu) and copper containing compounds used as bactericides and fungicides in plants, Cu stress has become one of the serious environmental problems that affect plant growth and development. In order to uncover the hidden response mechanisms of Cu stress, two small RNA libraries were constructed from Cu-treated and water-treated (Control) leaves of ‘Summer Black’ grapevine. Following high-throughput sequencing and filtering, a total of 158 known and 98 putative novel miRNAs were identified in the two libraries. Among these, 100 known and 47 novel miRNAs were identified as differentially expressed under Cu stress. Subsequently, the expression patterns of nine Cu-responsive miRNAs were validated by quantitative real-time PCR (qRT-PCR). There existed some consistency in expression levels of Cu-responsive miRNAs between high throughput sequencing and qRT-PCR assays. The targets prediction of miRNAs indicates that miRNA may regulate some transcription factors, including AP2, SBP, NAC, MYB and ARF during Cu stress. The target genes for two known and two novel miRNAs showed specific cleavage sites at the 10th and/or 11th nucleotide from the 5′-end of the miRNA corresponding to their miRNA complementary sequences. The findings will lay the foundation for exploring the role of the regulation of miRNAs in response to Cu stress and provide valuable gene information for breeding some Cu-tolerant grapevine cultivars.

A new solution is presented to analyze the electromagnetic response of an anisotropic sphere when both the spatial dispersion and gyrotropy are simultaneously accounted for. By employing the Mie theory, the electromagnetic fields that can be decomposed into source-free and curl-free vector spherical harmonics are derived analytically by applying appropriate boundary conditions, namely, the continuity of the tangential components of electric fields and magnetic fields, respectively, together with the continuity of the normal components of the polarization phasor current density. Moreover, all expressions involving gyrotropic tensors are calculated in the corresponding principle coordinates, yielding analytical expressions. The derived solutions are capable of dealing with incident electromagnetic waves at an arbitrary incident angle and for arbitrary polarizations. Numerical validations are performed by comparing our results with those obtained for simplified models and also with numerical solutions, as well as with the results obtained from other existing approaches. The impact of the temperature and the dispersion effects on the modified circular dichroism has been investigated. It is demonstrated that the interplay of spatial dispersion and gyrotropy can bring narrower relative frequency shifts between the magneto-plasmonic resonances of the left-circularly-polarized and the right-circularly-polarized wave excitations, along with a blue-shift of the resonance and the reduced magnitude of the spectrum. The proposed method shows its capability and flexibility to analyze the nonlocal response of gyrotropic plasmonic semiconductors under an external static magnetic field, which enables us to rapidly validate nonlocal magneto-plasmonic applications.

In this work, we present a numerically efficient technique, called the Characteristics Basis Function Method (CBFM), to model large non-uniform plasmonic arrays of nanorods. The use of the CBFM dramatically reduces the number of unknowns without sacrificing the computational accuracy and enables us to handle large, truncated and non-uniform arrays. The method is rigorous and includes the mutual coupling effects to obtain accurate results. Furthermore, the method is readily parallelizable and is capable of handling arrays comprised of nanoantennas with complex shapes, without any difficulty.

In this work, we generalize the cascading scattering matrix algorithm for calculating the optical response of concentric multilayered structures comprised of either plasmonic metal or dielectric, within the framework of hydrodynamic convection-diffusion model of electrodynamics. Two additional boundary conditions, namely, the continuity of first order pressure of free electron density and the continuity of normal components of free charge velocity, respectively, are adopted in order to handle the behaviour at interfaces involving metals. Scattering matrices at interfaces can be readily obtained and cascaded to obtain the modal coefficients in each layer by expanding electromagnetic waves in harmonic modes with cylindrical vector wave functions. We have validated the proposed method by analyzing the optical responses of several configurations of nanostructures, including a bi-metallic nanocylinder and a hyperlens. We found that nonlocal effects can be important for small structures, when the characteristic size is comparable to the Fermi wavelength. The proposed method shows its capability and flexibility to solve hybrid metal-dielectric multilayer structures even when the number of layers is large. Although we have discussed our method in the context of the retarded radiation regime, it can be applied in quasi-static scenarios without any difficulties. Furthermore, it may be extended to solve similar problems in other areas of physics, such as acoustics.

In this work, we present the design of a low-profile circularly polarized antenna with a wide beam-width for low-angle coverage. The antenna consists of two parts: a dielectrically loaded short circuited quadrifilar helical antenna locates at the center, with its four ports terminated by 58 ohm impedance each. Additionally, four monopoles with 90° phase progression are placed around the helix, and sections of Archimedean spiral are used to topload the monopoles. The designed antenna has a peak gain of approximately 3dB and its 3dB beam width is 150°. The axial ratio of the antenna is less than 3 in the entire upper hemisphere over a wide frequency band, and its bandwidth is 18%.

We analyze large non-uniform optical antenna arrays of nanorods, which form optical vortices, axicons and lenses, by using a numerically efficient technique, called the Characteristics Basis Function Method (CBFM). The efficiency is realized by deriving an accurate, efficient simplified representation of nanorod, and by using the CBFM, which not only reduces the number of unknowns significantly without sacrificing the computational accuracy, but also enables us to handle large, truncated and non-uniform arrays. The method is numerically rigorous and includes all of the mutual coupling effects to obtain accurate results. Furthermore, it is readily parallelizable and can be generalized to handle more complex shapes of nanoantennas, without any difficulty.

In this paper, we derive the optical response of nanowire dimers with subnanometer gap sizes using different models, viz., the classical, quantum-corrected, nonlocal, and quantum-corrected nonlocal models. Our results indicate that both the quantum tunneling and the nonlocal response should be considered for the gap sizes less than 0.5 nm. We find that, when the quantum tunneling cannot be neglected, the nonlocal response is crucial in explaining the field enhancement at higher frequencies instead of the field collapse phenomenon if the nonlocal effect is ignored.