PMONN: an optical neural network for photonic integrated circuits based on micro-resonator.

We propose an improved optical neural network (ONN) circuit architecture based on conventional micro-resonator ONNs, called the Phase-based Micro-resonator Optical Neural Network (PMONN). PMONN's core architecture features a Convolutions and Batch Normalization (CB) unit, comprising a phase-based (PB) convolutional layer, a Depth-Point-Wise (DPW) convolutional layer, and a reconstructed Batch Normalization (RBN) layer. The PB convolution kernel uses modulable phase shifts of Add-drop MRRs as learnable parameters and their optical transfer function as convolution weights. The DPW convolution kernel amplifies PB convolution weights by learning the amplification factors. To address the internal covariate shift during training, the RBN layer normalizes DPW outputs by reconstructing the BN layer of the electronic neural network, which is then merged with the DPW layer in the test stage. We employ the tunable DAs in the architecture to implement the merged layer. PMONN achieves 99.15% and 91.83% accuracy on MNIST and Fashion-MNIST datasets, respectively. This work presents a method for implementing an optical neural network on the improved architecture based on MRRs and increases the flexibility and reusability of the architecture. PMONN has potential applications as the backbone for future optical object detection neural networks.

Design and optimization of an SOI-based electro-absorption-type VOA.

A silicon-on-insulator (SOI) variable optical attenuator (VOA) based on the plasma dispersion effect is optimized and realized, and the effects of doping concentration and distance about the VOA's modulation depth and attenuation efficiency are investigated. Two structures of the VOA component are designed to achieve low power consumption, high stability, and high modulation efficiency. The modulation depth of the series VOA scheme reached 60.11 dB, and the insertion loss is only 4.87 dB. Compared with conventional components, our optimized VOA can not only improve the modulation accuracy and efficiency but also reduce the wavelength dependence.

Low dark current density extended short-wavelength infrared superlattice photodetector with atomic layer deposited Al2O3 passivation.

We report on a low dark current density P-B-i-N extended short-wavelength infrared photodetector with atomic layer deposited (ALD) A l 2 O 3 passivation based on a InAs/GaSb/AlSb superlattice. The dark current density of the A l 2 O 3 passivated device was reduced by 38% compared to the unpassivated device. The cutoff wavelength of the photodetector is 1.8 µm at 300 K. The photodetector exhibited a room-temperature (300 K) peak responsivity of 0.44 A/W at 1.52 µm, corresponding to a quantum efficiency of 35.8%. The photodetector exhibited a specific detectivity (D ∗) of 1.08×1011 c m⋅H z 1/2/W with a low dark current density of 3.4×10-5 A/c m 2 under -50m v bias at 300 K. The low dark current density A l 2 O 3 passivated device is expected to be used in the fabrication of extended short-wavelength infrared focal plane arrays for imaging.

A Comprehensive Review of the Current Knowledge of Chlorfenapyr: Synthesis, Mode of Action, Resistance, and Environmental Toxicology.

Creating new insecticide lead compounds based on the design and modification of natural products is a novel process, of which chlorfenapyr is a typical successful example. Chlorfenapyr is an arylpyrrole derivative that has high biological activity, a wide insecticidal spectrum, and a unique mode of action. For decades, a series of chlorfenapyr derivatives were designed and synthesized continuously, of which many highly active insecticidal compounds were discovered sequentially. However, due to the widespread application of chlorfenapyr and its degradation properties, some adverse effects, including pest resistance and environmental toxicity, occurred. In this review, a brief history of the discovery and development of chlorfenapyr is first introduced. Then, the synthesis, structural modification, structure activity relationship, and action mechanism of arylpyrroles are summarized. However, challenges and limitations still exist, especially in regard to the connection with pest resistance and environmental toxicology, which is discussed at the end of this review. This comprehensive summary of chlorfenapyr further promotes its progress and sensible application for pest management.

Modeling and simulation of all-optical diffractive neural network based on nonlinear optical materials.

In this Letter, we propose an all-optical diffractive deep neural network modeling method based on nonlinear optical materials. First, the nonlinear optical properties of graphene and zinc selenide (ZnSe) are analyzed. Then the optical limiting effect function corresponding to the saturation absorption coefficient of the nonlinear optical materials is fitted. The optical limiting effect function is taken as the nonlinear activation function of the neural network. Finally, the all-optical diffractive neural network model based on nonlinear materials is established. The numerical simulation results show that the model can effectively improve the nonlinear representation ability of the all-optical diffractive neural network. It provides a theoretical support for the further realization of a photonic artificial intelligence chip based on nonlinear optical materials.

T-shaped silicon waveguide coupled with a micro-ring resonator-based Fano resonance modulator.

Fano resonance has an asymmetric and sharp resonance peak near the resonance wavelength, enhancing optical modulation performance. Here, a Fano resonant silicon optical modulator with a micro-ring resonator (MRR) coupled with a T-shaped waveguide is designed. Compared with an MRR modulator, a Fano resonance-based modulator has a smaller wavelength range of changes in optical intensity (from 0 a.u. to 1 a.u.). Under the condition of achieving the same light intensity change, Fano resonance only needs to shift the wavelength by 0.07 times compared with MRR. By optimizing the doping section and the Fano resonance line shape, the modulation depth of the Fano modulator is 12.44 dB, and an insertion loss of 0.41 dB is obtained. Moreover, it improves the modulation linearity. This modulator provides a new idea, to the best of our knowledge, for the single-cavity Fano resonance modulator.

Quality of Life in Patients With Velopharyngeal Insufficiency in West China.

OBJECTIVE: This study aimed to investigate the quality of life (QOL) of patients with cleft lip and palate and velopharyngeal insufficiency (VPI) in relation to sex, age, age at initial cleft lip surgery, and age at initial cleft palate surgery. DESIGN: This is a cross-sectional study. SETTING: The study was conducted in a tertiary medical center. PARTICIPANTS: The participants were caregivers of 72 patients with cleft lip and palate and VPI aged 4 to 20 years. MAIN OUTCOME MEASURE(S): Participants completed the Chinese version of the caregiver report of the VPI Effects on Life Outcomes (VELO) questionnaire. The Mann-Whitney U test was used to evaluate the patients' sex, age, age at initial cleft lip repair, and age at initial cleft palate repair in relation to VELO total score and domains. Spearman correlation analysis was completed including all study variables. Associations between the study variables and the VELO total score were tested using a generalized linear mixed model. RESULTS: In the univariate analysis, patients' age and age at initial cleft palate surgery influenced the QOL of patients with VPI. There were no differences in the VELO total score or domains based on sex or age at first cleft lip surgery. In the generalized linear mixed model, patients older than 8 years had higher VELO total scores. CONCLUSIONS: By caregiver report, the QOL of patients under age 8 years with VPI was lower than older patients. In addition, the caregiver impact domain was higher for parents of children who had their initial cleft palate surgery at age 2 years or younger.

Unravelling the Polytoxicology of Chlorfenapyr on Non-Target HepG2 Cells: The Involvement of Mitochondria-Mediated Programmed Cell Death and DNA Damage.

Chlorfenapyr (CHL) is a type of insecticide with a wide range of insecticidal activities and unique targets. The extensive use of pesticides has caused an increase in potential risks to the environment and human health. However, the potential toxicity of CHL and its mechanisms of action on humans remain unclear. Therefore, human liver cells (HepG2) were used to investigate the cytotoxic effect and mechanism of toxicity of CHL at the cellular level. The results showed that CHL induced cellular toxicity in HepG2 cells and induced mitochondrial damage associated with reactive oxygen species (ROS) accumulation and mitochondrial calcium overload, ultimately leading to apoptosis and autophagy in HepG2 cells. Typical apoptotic changes occurred, including a decline in the mitochondrial membrane potential, the promotion of Bax/Bcl-2 expression causing the release of cyt-c into the cytosol, the activation of cas-9/-3, and the cleavage of PARP. The autophagic effects included the formation of autophagic vacuoles, accumulation of Beclin-1, transformation of LC3-II, and downregulation of p62. Additionally, DNA damage and cell cycle arrest were detected in CHL-treated cells. These results show that CHL induced cytotoxicity associated with mitochondria-mediated programmed cell death (PCD) and DNA damage in HepG2 cells.

Effect of ischemic preconditioning on radiation damage to the submandibular gland in rats.

To investigate the effects of radiation on rat submandibular glands and the possible protective effects of ischemic preconditioning, the submandibular glands of Wistar rats were subjected to in situ radiation after ischemic preconditioning. The glands were exposed to X-radiation at a single dose of 20 Gy. Ischemic preconditioning was achieved by three min of ischemia and three min of reperfusion, repeated three times before irradiation. Salivary secretion, histological changes, alterations in tight junctions, and the levels of oxidative stress, pro-inflammatory cytokines, and water secretion proteins mediated by the muscarinic acetylcholine M3 subtype receptor were determined at 1 and 12 weeks post-irradiation. In glands subjected to irradiation only, the secretion, superoxide dismutase activity, tight junction width, acinar cell number, and M3 receptor and aquaporin-5 levels were lower at 1 and 12 weeks than seen in the ischemically preconditioned irradiated glands. In contrast, tumor necrosis factor-α, malondialdehyde, myeloperoxidase activity, and the expression of the tight junction protein claudin-4 were significantly higher in the irradiated only glands. Our study revealed that radiation caused a series of injury-stress responses, especially damage to the water secretion pathway mediated by the M3 receptor that ultimately led to hyposecretion, which might play an important role in the dysfunction of the irradiated only glands. Ischemic preconditioning reduced the radiation-induced injury to submandibular glands and ameliorated salivary hyposecretion.

Toxicity and physiological actions of biflavones on potassium current in insect neuronal cells.

Stellera chamaejasme L. is a Chinese traditional herb. It has a long history and many medicinal usages. Biflavones, one of the main active ingredients in S. chamaejasme's roots, possess excellent insecticidal activities both in vivo and in vitro. However, the mechanism of these compounds and its potential molecular targets on insect cell were still not clear. Here the whole cell patch clamp technique was used to investigate whether biflavones affects voltage-gated potassium channels (Kv) on insect neuronal cells (AW1 and WG2). The results confirmed that both the three biflavones: neochamaejasmin A (NCA), neochamaejasmin B (NCB) and isochamaejasmin A (ICM) can significantly inhibit the A-type potassium current (IA) than delayed rectifier potassium current (IK) expressed on insect cells. Moreover, ICM stood out as the strongest inhibition activity on IA with IC50 value of 106.75 µM. Multiple results suggest that the inhibition of potassium current was related to the gating modification of biflavones. ICM produced concentration dependent hyperpolarizing shifts in the voltage dependence of channel steady-state activation and inactivation. Maximal shifts of the ICM-induced V0.5, were -15.1 mV for activation and -6.93 mV for inactivation. ICM also prolonged recovery from inactivation of current. Moreover, the biflavones could inhibited AW1 cell survival in both dose- and time-dependent manners with well correlation of K+ inhibitory activity. Our study showed that biflavones from S. chamaejasme exhibiting significant blocked effects on Kv of AW1 cells and inhibited cell proliferation. These findings may not only show the toxic mechanisms of biflavones on insect cells, but also suggest that Kv channel play an important role in biflavones' mode of action and may be the new targets for designing novel insecticides.

Improved oral bioavailability and anti-chronic renal failure activity of chrysophanol via mixed polymeric micelles.

AIMS: This study was designed to prepare chrysophanol-loaded micelles (CLM) to improve the oral bioavailability, targetability and anti-chronic renal failure (CRF) activity of chrysophanol (CH). METHODS: The preparation of CLM was achieved via thin-film dispersion technique. The in vitro release of CLM compared with free CH was measured in phosphate buffer solution (PBS) containing 0.5%w/v sodium dodecyl sulphate (pH 6.8) while the pharmacokinetic and anti-CRF activity study was also conducted in rats. Moreover, the tissue distribution of CLM was investigated in the mice. RESULTS: The CLM had particle size (PS) of 29.64 ± 0.71 nm, and encapsulation efficiency (EE) of 90.48 ± 1.22%w/w. The cumulative release rate of CH from the micellar system was significantly higher than that of the free CH (86%m/m vs. 15%m/m, p < 0.01). In vivo pharmacokinetic studies showed that the bioavailability of CLM after oral administration was substantially improved (about 3.4 times) compared with free drugs (p < 0.01). Also, it was observed that CLM accumulated well in the liver and brain. Moreover, in vitro renal podocytes study showed that CLM had better protection against renal podocyte damage than the free CH. In addition, CLM significantly (p < 0.01) reduced levels of blood urea nitrogen (BUN), kidney injury molecule-1 (Kim-1), and serum creatinine (SCr), which obviously improved kidney damage in rats with CRF. CONCLUSIONS: Collectively, these findings suggest that mixed micelles may be used as a promising drug delivery system for oral bioavailability improvement and concomitantly enhance the anti-CRF activity of CH, as well as provide a basis for the clinical application of CH.

Polymorphisms of pfcrt, pfmdr1, and K13-propeller genes in imported falciparum malaria isolates from Africa in Guizhou province, China.

BACKGROUND: Imported falciparum malaria from Africa has become a key public health challenge in Guizhou Province since 2012. Understanding the polymorphisms of molecular markers of drug resistance can guide selection of antimalarial drugs for the treatment of malaria. This study was aimed to analyze the polymorphisms of pfcrt, pfmdr1, and K13-propeller among imported falciparum malaria cases in Guizhou Province, China. METHOD: Fifty-five imported falciparum malaria cases in Guizhou Province during 2012-2016 were included in this study. Their demographic information and filter paper blood samples were collected. Genomic DNA of Plasmodium falciparum was extracted from the blood samples, and polymorphisms of pfcrt, pfmdr1, and K13-propeller were analyzed with nested PCR amplification followed by sequencing. Data were analyzed with the SPSS17.0 software. RESULTS: The prevalence of pfcrt K76T, pfmdr1 N86Y, and pfmdr1 Y184F mutation was 56.6, 22.2, and 72.2%, respectively, in imported falciparum malaria cases in Guizhou Province. We detected two mutant haplotypes of pfcrt, IET and MNT, with IET being more commonly found (54.7%), and five mutant haplotypes of pfmdr1, of which NFD was the most frequent (53.7%). There were totally 10 combined haplotypes of pfcrt and pfmdr1, of which the haplotype IETNFD possessed a predominance of 28.8%. In addition, three nonsynonymous mutations (S459T, C469F, and V692L) and two synonymous mutations (R471R and V589V) were detected in K13-propeller, all having prevalence less than 6.0%. In particular, a candidate K13 resistance mutation, C469F, was identified for the first time from Democratic Republic of the Congo with the prevalence of 2.0%. CONCLUSIONS: The high prevalence of IET haplotype of pfcrt and NFD haplotype of pfmdr1 suggests the presence of chloroquine, artemether/lumefantrine, and dihydroartemisinin/piperaquine resistance in these cases. Therefore cautions should be made to artemisinin therapy for P. falciparum in Africa. Continuous monitoring of anti-malarial drug efficacy in imported malaria cases is helpful for optimizing antimalarial drug therapy in Guizhou Province, China.

Non-contact temperature-independent random-displacement sensor using two fiber Bragg gratings.

We present a full-range displacement sensor system using two fiber Bragg gratings (FBGs). The magnetic-scale-combined FBGs allow the exploration of random position. The sinusoidal function variations are displayed by two detectors with a phase difference of 90 deg, and the optimal magnetic gap is explored through numerical simulations. The feasibility of the method is demonstrated in experiments that show the sinusoidal relation between center wavelength shifts with the linear displacement. Results showed that the amplitudes of the tensile-compressive load were 446.1 µÏµ and 434.7 µÏµ, respectively, with linearity of 0.998 and 0.999 at 1.5 mm between the detector and the magnetic scale. These results demonstrate that the sensors can realize non-contact, temperature-independent and full-range measurement.

Fiber Bragg grating-based measurement of random-rotation parameters.

A preloaded rotational sensor featuring a spring packaged within the magnetic head has been proposed and experimentally demonstrated. The aforementioned fiber Bragg grating-based system can convert the strain information into rotation angles without rotation angle limitations in terms of the proposed angle transfer mathematical model. The random-angular displacements were well fitted by the model with the maximum deviation of 0.5°. The linearity of the calculated rotational velocity reaches up to 0.998 in the range of 0 to 2021.4 rpm. This sensor can also be applied in the angular acceleration measurement.

[Single-tube Single-run Multiplex PCR Detects Mixed Samples with Four Species of Plasmodium].

OBJECTIVE: To establish a single-tube single-run multiplex PCR technique that can detect single or mixed samples with four species of Plasmodium. METHODS: Folding primers were designed based on the fast nested PCR. The reaction component concentrations were optimized and the primers were selected based on the annealing temperature. The established single-tube single-run folding-primer multiplex PCR (FP-PCR) was tested for its sensitivity and specificity to detect single-species and mixed samples with P. vivax, P. falciparum, P. ovale (including P. ovale wallikeri) and/or P. malariae. RESULTS: In all the seven experimental repeats, FP-PCR successfully detected single-species infection for all the four species, with the detection limit reaching or close to 1 parasite/µl blood. For mixed infections with 2-4 species at different densities with the highest being 100 times of the lowest, FP-PCR identified all the species in each combination in 57 out of 84 tests. Further, in 10 dried blood samples on filter paper from healthy subjects, no FP-PCR amplification was found, except weak formation of dimers. CONCLUSION: FP-PCR is a simple and sensitive method for detecting both single-species and mixed infections with human Plasmodium, and can be applied for malaria diagnosis, screening and monitoring.

[Comparison of Malaria Diagnosis between County and Provincial Laboratories in Guizhou Province].

Malaria cases reported by county laboratories were further tested in the provincial laboratory in Guizhou province by using PCR test and microscopy. The consistency between PCR and microscopic results in the provincial laboratory was set as the basis for evaluation of microscopic results in county laboratories. In 89 samples, 24 were identified by PCR to be positive for malaria, among which 15 were infected with P. falciparum, 7 with P. vivax, and 2 with P. ovale; all were imported cases. And 21 samples had consistent identifications by PCR test and microscopic examination in the provincial laboratory. The total coincidence rate between county and provincial laboratories was 79.8%(67/84), and the undetected and error rates in county laboratories were 9.5%(2/21) and 23.8% (15/63), respectively. The Kappa value between county and provicial diagnosis was 0.6, being at the medium-to-high level of consistency.

[Proteomic analysis of Cryphonectria parasitica infected by a virulence-attenuating hypovirus].

OBJECTIVE: Chestnut blight fungus Cryphonectria parasitica and hypovirus constitute a model system to study fungal pathogenesis and host-virus interaction. Proteomic analysis of chestnut blight fungus upon hypovirus infection was conducted to find the differentially expressed host proteins. METHODS: According to the characteristics of this filamentous fungus, an optimized extraction protocol for fungal total protein was developed. Two-dimensional electrophoresis (2-DE) was used for comparative proteomic analysis of wild strain EP155 and hypovirus-infected strain EP713. The quantitative RT-PCR was applied to analyze mRNA expression level of protein-coding genes. RESULTS: In total 71 protein spots were detected to be differentially expressed on the base of EP155 of which 19 up-regulated and 52 down-regulated. Fifty-eight unique proteins were identified by mass spectrometry. Further study on quantitative RT-PCR indicated that the regulation of related host genes by hypovirus occurred at different levels. CONCLUSION: The TCA cycle of C. parasitica was weakened after hypovirus infection and the process of methylation was regulated by hypovirus. Meanwhile, viral regulation of virulence factors also contributed to the phenomenon of hypovirulence.

The Quality Evaluation of Highland Barley and Its Suitability for Chinese Traditional Tsampa Processing.

The physicochemical traits of highland barley prominently affect the quality of Tsampa. To find out the relevance between the physicochemical properties of raw material and the texture parameters of processed products, twenty-five physicochemical traits and ten quality parameters for seventy-six varieties of highland barley were measured and analyzed. The results showed that there was a significant difference between the physicochemical indexes for highland barleys of various colors. The dark highland barley generally has more fat, protein, total dietary fiber, phenolic, Mg, K, Ca, and Zn and less amylose, Fe, Cu, and Mo than light colored barley. Then, these highland barleys were made into Tsampa. A comprehensive quality evaluation model based on the color and texture parameters of Tsampa was established through principal component analysis. Then, cluster analysis was used to classify the tested samples into three edible quality grades predicated on the above evaluation model. At last, the regression analysis was applied to establish a Tsampa quality predictive model according to the physicochemical traits of the raw material. The results showed that amylose, protein, ß-Glucan, and a* and b* could be used to predict the comprehensive quality of Tsampa. The predicted results indicated that 11 of 14 validated samples were consistent with the actual quality, and the accuracy was above 78.57%. Our study built the approach of the appropriate processing varieties evaluation. It may provide reference for processing specific highland barley.

Unsupervised domain adaptation based on feature and edge alignment for femur X-ray image segmentation.

The gold standard for diagnosing osteoporosis is bone mineral density (BMD) measurement by dual-energy X-ray absorptiometry (DXA). However, various factors during the imaging process cause domain shifts in DXA images, which lead to incorrect bone segmentation. Research shows that poor bone segmentation is one of the prime reasons of inaccurate BMD measurement, severely affecting the diagnosis and treatment plans for osteoporosis. In this paper, we propose a Multi-feature Joint Discriminative Domain Adaptation (MDDA) framework to improve segmentation performance and the generalization of the network in domain-shifted images. The proposed method learns domain-invariant features between the source and target domains from the perspectives of multi-scale features and edges, and is evaluated on real data from multi-center datasets. Compared to other state-of-the-art methods, the feature prior from the source domain and edge prior enable the proposed MDDA to achieve the optimal domain adaptation performance and generalization. It also demonstrates superior performance in domain adaptation tasks on small amount datasets, even using only 5 or 10 images. In this study, MDDA provides an accurate bone segmentation tool for BMD measurement based on DXA imaging.

Verification of clinically diagnosed cases during malaria elimination programme in Guizhou Province of China.

BACKGROUND: China is implementing a National Malaria Elimination Programme. A high proportion of clinically diagnosed malaria cases is reported in some provinces of China. In order to understand the exact situation and make clear the nature of these patients, it is of much importance to make case verifications, particularly from the pathogenic perspective. METHODS: Guizhou Province was targeted because of its high proportion of clinically diagnosed malaria cases. After random selection of around 10% of malaria cases from 1 May 2011 to 30 April 2012, reported through the national web-based case reporting system from this province, field verifications were made on 14-17 May 2012 as follows. Firstly, the reported information of each case was rechecked with the onsite case registrations and investigation forms, and an in-depth interview was conducted with each patient. Secondly, the patient's blood smears kept by local CDC were cross-checked microscopically by a national experienced microscopist. Thirdly, two kinds of polymerase chain reaction (PCRs). including Tag-primer nested/multiplex PCR (UT-PCR) based on cytochrome oxidase gene (cox I) and nested PCR based on 18s rRNA gene were performed simultaneously using local CDC kept filter paper of dry blood samples to identify the Plasmodium spp. RESULTS: Twelve out of 152 malaria cases were selected, including nine clinically diagnosed malaria cases, two confirmed falciparum malaria cases and one confirmed vivax malaria case. The original case documents on the site were completely in conformity with their reported data, and all the patients recalled their malaria symptoms and being cured only after consuming the corresponding anti-malarial drugs. Moreover, the re-examination results of microscopy and PCR were exactly in agreement with the original tests. DISCUSSION: No inconsistent results were found against the reported case information in the present study and the reasons for clinically diagnosed patients remains unclear. Uniform and standardized sample collection and processing should be trained among clinicians, more sensitive and specific techniques should be explored to used in malaria diagnosis. A further study is needed in order to be more observationally focussed rather than retrospective.