A Novel Contrastive Self-Supervised Learning Framework for Solving Data Imbalance in Solder Joint Defect Detection.

Poor chip solder joints can severely affect the quality of the finished printed circuit boards (PCBs). Due to the diversity of solder joint defects and the scarcity of anomaly data, it is a challenging task to automatically and accurately detect all types of solder joint defects in the production process in real time. To address this issue, we propose a flexible framework based on contrastive self-supervised learning (CSSL). In this framework, we first design several special data augmentation approaches to generate abundant synthetic, not good (sNG) data from the normal solder joint data. Then, we develop a data filter network to distill the highest quality data from sNG data. Based on the proposed CSSL framework, a high-accuracy classifier can be obtained even when the available training data are very limited. Ablation experiments verify that the proposed method can effectively improve the ability of the classifier to learn normal solder joint (OK) features. Through comparative experiments, the classifier trained with the help of the proposed method can achieve an accuracy of 99.14% on the test set, which is better than other competitive methods. In addition, its reasoning time is less than 6 ms per chip image, which is in favor of the real-time defect detection of chip solder joints.

Improving the Mechanical Properties of Hot Rolled Low-Carbon Copper-Containing Steel by Adjusting Quenching Roll Speed.

This paper presents a comprehensive study of the impact of quenching roll speed on enhancing the low-temperature toughness of a low-carbon copper-containing steel. The microstructure characteristics, such as the prior austenite grains, and the distribution and volume fraction of precipitates, are observed using optical microscopy, scanning electron microscopy, transmission electron microscopy, and small-angle scattering X-ray. The results show that a decrease in the quenching roller speed (2 m/min) contributes to the achievement of more excellent low-temperature toughness (the average value is 232 J), although the prior austenite grains exhibit a relatively larger size in this case. The tempering treatment results in the precipitation of a large amount of 9R-type Cu-rich particles, regardless of the quenching roller speed. Reducing the quenching roller speed contributes to the increase in the volume fraction of Cu-rich particles, which is considered to be the main factor contributing to the achievement of excellent low-temperature toughness.

A wideband, high-resolution vector spectrum analyzer for integrated photonics.

The analysis of optical spectra-emission or absorption-has been arguably the most powerful approach for discovering and understanding matter. The invention and development of many kinds of spectrometers have equipped us with versatile yet ultra-sensitive diagnostic tools for trace gas detection, isotope analysis, and resolving hyperfine structures of atoms and molecules. With proliferating data and information, urgent and demanding requirements have been placed today on spectrum analysis with ever-increasing spectral bandwidth and frequency resolution. These requirements are especially stringent for broadband laser sources that carry massive information and for dispersive devices used in information processing systems. In addition, spectrum analyzers are expected to probe the device's phase response where extra information is encoded. Here we demonstrate a novel vector spectrum analyzer (VSA) that is capable of characterizing passive devices and active laser sources in one setup. Such a dual-mode VSA can measure loss, phase response, and dispersion properties of passive devices. It also can coherently map a broadband laser spectrum into the RF domain. The VSA features a bandwidth of 55.1 THz (1260-1640 nm), a frequency resolution of 471 kHz, and a dynamic range of 56 dB. Meanwhile, our fiber-based VSA is compact and robust. It requires neither high-speed modulators and photodetectors nor any active feedback control. Finally, we employ our VSA for applications including characterization of integrated dispersive waveguides, mapping frequency comb spectra, and coherent light detection and ranging (LiDAR). Our VSA presents an innovative approach for device analysis and laser spectroscopy, and can play a critical role in future photonic systems and applications for sensing, communication, imaging, and quantum information processing.

Synergistic Effect of Nano-Silica and Intumescent Flame Retardant on the Fire Reaction Properties of Polypropylene Composites.

Silica nanoparticles (nano-silica) were used as synergistic agents with ammonium polyphosphate (APP) and pentaerythritol (PER) to enhance flame retardancy of polypropylene (PP) in this research. The composites were prepared using a melt-mixing method. The influences of nano-silica on the fire performance of composites were thoroughly discussed, which promotes understanding of nano-silica on the flame-retardant performance of polypropylene composite. Scanning electron microscope (SEM) and energy-dispersive spectrometer (EDS) results indicated that the nano-silica with a diameter of about 95 ± 3.9 nm were dispersed favorably in the composite matrix, which might elevate its synergistic effect with intumescent flame retardant and improve the flame retardancy of polypropylene composite. The synergistic effects between nano-silica and intumescent flame retardant on PP composites were studied using the limiting oxygen index (LOI), UL-94 test, and cone calorimeter test (CCT). The total amount of flame retardant was maintained at 30%. When the dosage of nano-silica was 1 wt.%, the LOI value of PP/IFR/Si1.0 composite reached 27.3% and its UL-94 classification reached V-1. Based on the parameters of the CCT, the introduction of nano-silica induced composites with depressed heat release rate (HRR) and peak heat release rate (PHRR). The PHRR of PP/IFR/Si0.5 was only 295.8 kW/m2, which was 17% lower than that of PP/IFR. Moreover, the time to PHRR of PP/IFR/Si0.5 was delayed to 396 s, which was about 36 s later than that without nano-silica. EDS was used to quantitatively analyze the distribution of silica in charred residue. The EDS results indicated that the silica tended to accumulate on the surface during the fire. The surface accumulation characteristic of silica endows it with the enhanced flame-retardant properties of polypropylene composite at a very small dosage (as low as 1 wt.%).

Repurposing of yunnan baiyao as an alternative therapy for minor recurrent aphthous stomatitis.

The study was designed to evaluate the efficacy and safety of an herbal extract of Yunnan Baiyao formulated in toothpaste as an alternative therapy for minor RAS. A randomized, double-blind, placebo-controlled clinical trial (from March 2010 to March 2011) was conducted on a cohort of 227 minor RAS patients. The toothpaste containing Yunnan Baiyao was used twice daily as part of the patient's routine oral hygiene for 5 days. An assessment of ulcerative size and pain was recorded on day 0 (baseline), day 3, and day 5. Any noted adverse reactions were recorded. All data were analyzed using the SAS software 8.0. As a result, the toothpaste containing Yunnan Baiyao began to present noticeable effectiveness on ulcer healing (ulcer size) by day 3 (27.5% versus 15.8%, P < 0.05), which further improved by day 5 when compared to the placebo (66.4% versus 50.0%, P = 0.01). A significant difference in alleviating pain was noted on day 5 for those who used the toothpaste containing Yunnan Baiyao (66.4% versus 51.8%, P < 0.05). No side effects were noted as a result of the Yunnan Baiyao. Therefore, Yunnan Baiyao may provide an alternative therapy for minor ulcers by promoting healing.

Radioprotective effects and mechanism of HL-003 on radiation-induced salivary gland damage in mice.

Ionizing radiation (IR) can cause damage to the structure and function of salivary glands. Our research group independently synthesized the ROS scavenger, HL-003. The aim of this study was to explore the protective effects and underlying mechanisms of HL-003 on radiation-induced salivary gland injury. Salivary flow rate measurement, H&E staining, immunohistochemistry, FRAP, TUNEL, and western blotting were used to evaluate the radioprotective effect on salivary glands. The results showed that HL-003 protected the salivary secretion function by protecting the AQP-5 protein, on the salivary epithelial cell membrane, from IR damage. HL-003 reduced oxidative stress in the salivary gland by regulating the expression of ROS-related proteins NOX4, SOD2, and 8-OHdG. Furthermore, HL-003 downregulated the expression of p-p53, Bax, caspase 3, and caspase 9, and upregulated the expression of Bcl-2, suggesting that it could inhibit the activation of p53 to reduce cell apoptosis. In conclusion, HL-003 is an effective radioprotector that prevents damage of the radiation-induced salivary gland.

Spatiotemporal patterns of global carbon intensities and their driving forces.

Carbon intensity (CI) is a valuable indicator of the balances struck by the world's governments between economic growth and environmental issues. This study investigates spatiotemporal variations in the CI levels related to energy consumption, as well as the spatial heterogeneity of its driving forces, in 208 countries globally during 2000-2018. To do this, we obtained data from the International Energy Agency (IEA) and the World Bank, employing methods of exploratory spatial data analysis (ESDA) and standard deviation ellipse (SDE) in order to analyze CI's spatiotemporal variations. We also performed a geographically weighted regression (GWR) analysis to determine the spatial heterogeneity of CI and the strength of its influencing factors. Our results reveal that: (1) Carbon emissions from energy consumption increased, while CI decreased globally, with the CI of most countries and regions declining significantly. (2) Global CI evidenced a heterogeneous spatial distribution, with higher-value areas concentrated in Asia and lower-value areas in Africa and Western Europe; obvious spatial agglomeration was also presented, especially with respect to High-High and Low-Low agglomerations, and the gravity center point moved from the northeast to the southwest. (3) The 8 influencing factors investigated in this study all had effective explanatory power in relation to CI globally. These factors showed significant spatial heterogeneity, and energy structure was the only factor to have a fully positive influence on CI, while foreign direct investment, foreign trade openness, industrial structure, total population, and energy intensity, mainly exerted a positive influence, and the urbanization rate and GDP per capita exerted a negative influence. By clarifying the spatiotemporal variations characteristics of global CI and the spatial heterogeneity of its influencing factors, this study provides a targeted reference for reducing CI and promoting sustainable development, globally.

Wafer-Scale Full-Coverage Self-Limiting Assembly of Particles on Flexible Substrates.

Self-limiting assembly of particles represents the state-of-the-art controllability in nanomanufacturing processes where the assembly stops at a designated stage, providing a desirable platform for applications requiring delicate thickness control such as optics, electronics, and catalytic systems. Most successes in self-limiting assembly are limited to self-assembled monolayers (SAMs) of small molecules on inorganic, chemically homogeneous rigid substrates (e.g., Au and SiO2) through surface-interaction mechanisms. Similar mechanisms, however, cannot achieve a uniform assembly of particles on flexible polymer substrates. The complex configurations and conformations of polymer chains create a surface with nonuniform distributions of chemical groups and phases. In addition, most assembly mechanisms require good solvent wettability, where many desirable but hard-to-wet particles and polymer substrates are excluded. Here, we demonstrate a collision-based self-limiting assembly (CSA) to achieve wafer-scale, full-coverage, close-packed monolayers of hydrophobic particles on hydrophobic polymer substrates in aqueous solutions. The kinetic assembly and self-limiting processes are facilitated and controlled by the combined acoustic and shear fields. We envision many applications in functional coatings and showcase their feasibility in structural coloration. Importantly, such functional coatings can be repaired using CSA, and both particles and polymer substrate can be recycled.

Evaluation of Eosinophilic Cationic Protein as a Marker of Alveolar and Cystic Echinococcosis.

Echinococcosis is a neglected zoonotic disease and a worldwide public health problem caused by infection with the larval stages of taeniid cestodes of the genus Echinococcus. In vitro studies have demonstrated a protoscolecidal effect of eosinophilic cationic protein (ECP), a granule protein of eosinophilic granulocytes, against E. granulosus. Therefore, the main objective of this study was to evaluate ECP as a biomarker in the treatment of alveolar echinococcosis (AE) and cystic echinococcosis (CE). Data were collected retrospectively from the Vienna Echinococcosis Cohort over 7 years until December 2020. Altogether, 32 patients (16 AE and 16 CE) were included. In the selected patients, serum ECP values were compared before and after the beginning of an operative and/or benzimidazole (BMZ) therapy. Mean ECP serum levels before intervention were significantly (p < 0.05) elevated at 34.0 ± 22.9 µg/L in AE patients and at 38.6 ± 19.9 µg/L in CE patients compared to the control group. After the intervention, mean ECP levels decreased significantly (p < 0.05) to 20.4 ± 14.6 µg/L in AE patients and to 22.4 ± 8.3 µg/L in CE patients. Furthermore, ECP showed a significant (p < 0.05) correlation of k = 0.56 with PET-CTI. Based on the significant decrease after operative and/or BMZ treatment and the correlation with clinical markers such as PET-CTI, it is recommended to investigate ECP more intensively as a marker of AE and CE in prospective studies with larger cohorts.

Real-time multi-task diffractive deep neural networks via hardware-software co-design.

Deep neural networks (DNNs) have substantial computational requirements, which greatly limit their performance in resource-constrained environments. Recently, there are increasing efforts on optical neural networks and optical computing based DNNs hardware, which bring significant advantages for deep learning systems in terms of their power efficiency, parallelism and computational speed. Among them, free-space diffractive deep neural networks (D2NNs) based on the light diffraction, feature millions of neurons in each layer interconnected with neurons in neighboring layers. However, due to the challenge of implementing reconfigurability, deploying different DNNs algorithms requires re-building and duplicating the physical diffractive systems, which significantly degrades the hardware efficiency in practical application scenarios. Thus, this work proposes a novel hardware-software co-design method that enables first-of-its-like real-time multi-task learning in D22NNs that automatically recognizes which task is being deployed in real-time. Our experimental results demonstrate significant improvements in versatility, hardware efficiency, and also demonstrate and quantify the robustness of proposed multi-task D2NN architecture under wide noise ranges of all system components. In addition, we propose a domain-specific regularization algorithm for training the proposed multi-task architecture, which can be used to flexibly adjust the desired performance for each task.

Bottom-up perceptual salience and top-down retro-cues concurrently determine state in visual working memory.

Recent studies have demonstrated that in visual working memory (VWM), only items in an active state can guide attention. Further evidence has revealed that items with higher perceptual salience or items prioritised by a valid retro-cue in VWM tend to be in an active state. However, it is unclear which factor (perceptual salience or retro-cues) is more important for influencing the item state in VWM or whether the factors can act concurrently. Experiment 1 examined the role of perceptual salience by asking participants to hold two features with relatively different perceptual salience (colour vs. shape) in VWM while completing a visual search task. Guidance effects were found when either colour or both colour and shape in VWM matched one of the search distractors but not when shape matched. This demonstrated that the more salient feature in VWM can actively guide attention, while the less salient feature cannot. However, when shape in VWM was cued to be more relevant (prioritised) in Experiment 2, we found guidance effects in both colour-match and shape-match conditions. That is, both more salient but non-cued colour and less salient but cued shape could be active in VWM, such that attentional selection was affected by the matching colour or shape in the visual search task. This suggests that bottom-up perceptual salience and top-down retro-cues can jointly determine the active state in VWM.

Synergistic Effect of Cefazolin Plus Fosfomycin Against Staphylococcus aureus in vitro and in vivo in an Experimental Galleria mellonella Model.

Objectives: This study investigated the synergistic in vitro and in vivo activity of cefazolin plus fosfomycin against methicillin-susceptible and methicillin-resistant S. aureus (MSSA and MRSA) to provide the basis for a potential treatment alternative. Methods: Antimicrobial susceptibility and in vitro synergy tests were performed with five MSSA and five MRSA isolates using the broth microdilution and chequerboard assays, respectively. The in vivo efficacy of cefazolin plus fosfomycin for the treatment of MRSA infections was assessed using the Galleria mellonella survival assay. Results: Using fractional inhibitory concentration index (FICI), the evaluated combination of cefazolin plus fosfomycin showed synergistic in vitro activity against all MSSA and MRSA isolates tested. In addition, cefazolin susceptibility was recovered in all MRSA isolates except one fosfomycin-resistant strain when combined with fosfomycin at readily achievable concentrations. The G. mellonella survival assay demonstrated highly synergistic in vivo activity of cefazolin plus fosfomycin, resulting in a 44-52% reduction in mortality when compared to cefazolin-alone and fosfomycin-alone, respectively. Conclusion: If susceptibility to fosfomycin is either confirmed or can be assumed based on local resistance patterns, combination therapy with cefazolin plus fosfomycin could be a valuable treatment option for empirical as well as targeted therapy of S. aureus and MRSA infections. Future studies proving the clinical significance of this combination therapy are therefore warranted.

Reducing adsorption of hydroxypropyl guar gum on sandstone by silicon nanoparticles.

Hydroxypropyl guar gum (HPG) is commonly used as the thicker of the fracturing fluid. It will be adsorbed on the sandstone that leads to decrease the permeability of the reservoir. Therefore, it is necessary to reduce the adsorption of HPG to decrease the permeability damage. The effect of silica nanoparticles (SNP) on the adsorption properties of HPG has been studied. X-ray photoelectron spectroscopy is employed to confirm the interaction force between HPG and sandstone. It is clear that hydrogen bonds is an important force of adsorption between HPG and sandstone. SNP can break hydrogen bonds between HPG and sandstone by occupying the rock surface, while altering the wettability of the rock. This results in effectively reducing the amount of HPG adsorption and retaining larger pores of the core after flooding with fracturing fluids. Adding SNP to HPG is an effective method to reduce reservoir damage.

Characters of DNA constitution in the rye B chromosome.

We have used chromosome microdissection and microcloning to construct a DNA library of the entire B chromosome (B) of rye. New rye B-specific sequences have been screened from this pool, blasted with other sequences and analyzed to elucidate the characters of DNA constitution and the possible pathway of the origin of the rye B chromosome. We report the discovery of a new sequence that is specific to the rye B centromere.

[Multicolor FISH analysis of rDNA and telomere on spin-ach].

In this study, multicolor FISH analysis on metaphase chromosomes of spinach with biotin-labeled 25S rDNA, DIG-labeled telomere sequences and biotin-labeled and DIG-labeled 5S rDNA was performed. There were six 25S rDNA loci, which were located on the satellites of the third, the fifth and the sixth chromosomes, four 5S rDNA loci, which were located on the long arms of the third and the fifth chromosomes. The telomere loci were located on the end of the sixth chromosome and also on both the end and centromeric regions of other chromosomes. This study is an important complement to both traditional karyotype analysis and FISH karyotype analysis in spinach.

[Analysis on genetic diversity of different Salvia miltiorrhiza geographical populations in China].

OBJECTIVE: To research on genetic diversity of different Salvia miltiorrhiza geographical populations in China. METHOD: The genetic diversity of 27 S. miltiorrhiza geographical populations from ten provinces in China was estimated using amplified fragment length polymorphism (AFLP) markers. The data of amplified bands were analyzed by the software POPGENE and SPSS. RESULT: The ten primers employed produced a total of 528 discernable and reproduceable amplified fragments. There were 476 polymorphic brands. The percentage of polymorphic bands with in different populations was 90.15%. Genetic diversity analysis showed that Neis gene diversity (He) was 0.261 2 and Shannon's genetic diversity index (1) was 0.403 3. The coefficient of gene similarity was 0.504 0-0.789 0 between populations. The cluster map including all samples were obtained by UPGMA. In the map, there were seven cluster groups and one individual outside the groups. CONCLUSION: The genetic diversity with in different geographical population of S. miltiorrhiza in China is plentiful.

[Karyotypes analysis of Ferula fukanensis].

OBJECTIVE: Study on the karyotypes analysis of Ferula fukanensis. METHOD: The young roots were treated with 0.000 2 mol x L(1) 8-Hydroxyquinoline for 3 h, carnoy's for 3 h, 1 mol x L(-1) HCl in 5 min,carbol fuchsin coloration for 2 min and the treated roots were utilizied to make the plate for observation. RESULT: The fukanensis is diploid. The chromosome number of somatic cells was 2n = 22. The karyotype formula is 2n = 2x = 20 = 16m + 4sm. The 4th and 10th are submetacentric, and the others are metacentric. CONCLUSION: The karyotype of F. fukanensis belongs to "2A" type of stebbins', and it is a primitive species.

[Studies on cytogeography of Pinellia ternata poliploid complex].

OBJECTIVE: In order to clarify the genetic background of Pinellia ternata germplasm resources in China, the chromosomal constitution and cytogeographical distribution of P. ternata were investigated in 27 different populations among 16 provinces and regions in China systematically. METHOD: Cytological and cytogeographical methods were used in the study. RESULT: P. ternata in China is a polyploid complex, which contains septuploid (2n = 7x = 91) , octoploid (2n = 8x = 104) , nonuploid (2n = 9x = 117) and decaploid (2n = 10x = 130). Meanwhile the aneuploid series (2n = 92, 103, 105, 115) of a minority of P. ternata were also found. CONCLUSION: The genetic differentiation and the phenomenon of ploidy miscellany commonly exist in the species of P. ternata in China, both for natural populations and cultivated populations. Toxicity and chemical components of different ploidy P. ternata should be clarified before the superior multiploid is selected for normalized plantation of the plant.

A clinical evaluation of amlexanox oral adhesive pellicles in the treatment of recurrent aphthous stomatitis and comparison with amlexanox oral tablets: a randomized, placebo controlled, blinded, multicenter clinical trial.

BACKGROUND: Amlexanox has been developed as a 5 percent topical oral paste for the treatment of patients with recurrent aphthous stomatitis (RAS) in most European countries. However, it is not yet available in China and has not been generally accepted in clinical treatment. The aim of this study was to explore the effectiveness of amlexanox oral adhesive pellicles in the treatment of minor recurrent aphthous ulcers, and compare the results with those of amlexanox oral adhesive tablets in order to analyse the difference between the two dosage forms of amlexanox. METHODS: We performed a randomized, blinded, placebo-controlled, parallel, multicenter clinical study. A total of 216 patients with minor recurrent aphthous ulcers (MiRAU) were recruited and randomized to amlexanox pellicles or placebo pellicles. Pellicles were consecutively applied four times per day, for five days. The size and pain level of ulcers were measured and recorded on treatment days 0, 4 and 6. Finally, the results were compared with those of our previous 104 cases treated with amlexanox tablets. RESULTS: Amlexanox oral adhesive pellicles significantly reduced ulcer size (P= 0.017 for day 4, P=0.038 for day 6) and alleviated ulcer pain (P=0.021 for day 4, P=0.036 for day 6). No significant difference was observed in the treatment effectiveness between the pellicle and tablet form of amlexanox. CONCLUSIONS: Amlexanox oral adhesive pellicles are as effective and safe as amlexanox oral adhesive tablets in the treatment of MiRAU for this Chinese cohort. However, pellicles seem to be more comfortable to use when compared with the dosage form of tablets. Therefore, in clinical practice, amlexanox oral adhesive pellicles may be a better choice for RAS patients. TRIALS REGISTRATION: Netherlands Trial Register NTR1727.

Multicolor fluorescence in situ hybridization with combinatorial labeling probes enables a detailed karyotype analysis of Larix principis-rupprechtii

The chromosomes (2n = 2x = 24) of Larix principis-rupprechtii are composed of six pairs of large metacentrics and six pairs of medium-sized submetacentrics. The identification of homologous pairs is hampered by their high degree of similarity at the morphological level in each group. As one of the most extensively used methods in molecular cytogenetics producing chromosome landmarks, fluorescence in situ hybridization (FISH) has significantly facilitated karyotype construction, especially in species with morphologically similar chromosomes. This study developed a simple but effective use of combinatorial labeling probes to distinguish chromosomes of Larix principis-rupprechtii by multicolor FISH. Three highly repetitive sequences in Larix were selected: 25S rDNA hybridized at all of the secondary constrictions of two pairs of metacentrics and the largest pair of submetacentrics; 5S rDNA hybridized at subtelomeric sites of one pair of metacentrics that also harboured 25S rDNA on different arms; LPD family sequences are tandem repeats hybridized at proximal regions of 22 chromosomes. The three different probes were labeled with only two different labels, hybridized to metaphase chromosomes of Larix principis-rupprechtii, simultaneously visualized, and unequivocally distinguished in a single FISH experiment. These multicolor FISH marks largely improved the karyotype analysis of Larix principis-rupprechtii.