Polyanionic Receptors for Carboxylates in Water.

Receptors for carboxylate anions have many possible biomedical applications, including mimicry of the vancomycin group of antibiotics.  However, binding carboxylates in water, the biological solvent, is highly challenging due to the hydrophilicity of these polar anions.  Here we report, for the first time, the recognition of simple carboxylates such as acetate and formate in water by synthetic receptors with charge-neutral binding sites.  The receptors are solubilised by polyanionic side-chains which, remarkably, do not preclude anion binding.  The tricyclic structures feature two identical binding sites linked by polyaromatic bridges, capable of folding into closed, twisted conformations.  This folding is hypothesised to preorganise the structures for anion recognition, mimicking the process which generates many protein binding sites.  The architecture is suitable for elaboration into enclosed structures with potential for selective recognition of biologically relevant carboxylates.

High responsivity of VIS-NIR photodetector based on Ag2S/P3HT heterojunction.

Ag2S quantum dot (QD) photodetectors (PDs) have attracted a lot of attention in the field of imaging system and optical communication. However, the current Ag2S PDs mainly works in the near-infrared band, and its detection ability in the visible band remains to be strengthened. In this paper, we used poly(3-hexylthiophene) (P3HT) with high carrier mobility and Ag2S QDs to construct heterojunction PD. Stronger absorption in blends with polymer P3HT compared to single Ag2S QDs. The optical absorption spectra show that the Ag2S/P3HT has strong light absorption peak at 394 and 598 nm. The results show that P3HT significantly enhances the absorption of Ag2S QDs from the visible to near-infrared band. The output characteristics, transfer characteristics and fast switching capability of the device at 405 nm, 532 nm and 808 nm were tested. The device has the responsivity of 6.05 A W-1, 83.72 A W-1and 37.31 A W-1under 405 nm, 532 nm and 808 nm laser irradiation. This work plays an important role in improving the detection performance of Ag2S QDs and broadening its applications in photoelectric devices for weak light and wide spectrum detection.

Laser waterless cleaning of residual organic solvents on the surface of polyurethane coatings.

Residual organic solvents have a great impact on the physical and mental health of equipment operators in industry and agriculture. Laser waterless cleaning technology of residual organic solvents on the surface of polyurethane coatings has great application prospects and is a good way to tackle the pollution problem. In this paper, the evolutionary behavior of a laser waterless cleaning mechanism and substrate surface state is analyzed. The influence law of laser energy density and scanning speed on the residual solvent cleaning effect was investigated. The optimal laser cleaning parameters were obtained by comprehensive evaluation of the substrate surface cleaning effect and microscopic morphology. The peak of solvent characteristics before and after laser cleaning was detected by Raman spectroscopy. The results demonstrated that the laser cleaning effect was better with the increase of energy density or the decrease of scanning speed in the substrate damage range, and the best laser cleaning parameters were laser energy density of 0.24J/c m 2 and scanning speed of 500 mm/s. A significant reduction of the peak of Raman spectroscopy was found, reflecting the excellent effect of laser waterless cleaning of residual organic solvents.

Silver nanoparticles-integrated terahertz metasurface for enhancing sensor sensitivity.

A silver nanoparticles (AgNPs)-integrated terahertz (THz) metasurface sensor was presented and applied to enhance the sensitivity of substance detection. Simulations and experiments were conducted to study the influence of AgNPs on the sensor performance. The enhancement of the local electric field excited by AgNPs can substantially strengthen the interaction between the THz waves and analytes, thereby increasing detection sensitivity. The experimental results indicate that the detection limit of the AgNPs-integrated metasurface sensor is improved by two orders of magnitude compared to that of the bare metasurface sensor without AgNPs. This study provides a convenient method to enhance the sensitivity of THz metasurface sensors.

Efficient mode converters and filters using asymmetrical directional couplers with subwavelength gratings.

Mode-division multiplexing (MDM) is a promising solution to improve data transmission capacity for future optical interconnect networks. Mode converters and mode filters play a key role in on-chip MDM systems. Here, we propose and experimentally demonstrate a device, enabling mode conversion and filtering simultaneously, which is composed of asymmetrical directional couplers with subwavelength gratings, in a small footprint of 14.7 µm × 1.42 µm. The device can realize optical mode conversion between the first-order transverse electric (TE) mode and the fundamental TE mode, and can also filter the fundamental TE mode efficiently. The conversion efficiency is over 95%, with a broad 1 dB bandwidth over 80 nm and a high mode extinction ratio of >29 dB. As a mode filter, strong mode elimination of >30 dB is achieved.

Semiconductor-based surface enhanced Raman scattering (SERS): from active materials to performance improvement.

Surface enhanced Raman scattering (SERS) is a powerful spectral analysis technique and has exhibited remarkable application prospects in various fields. The design and fabrication of high-performance SERS substrates is key to promoting the development of SERS technology. Apart from noble metal substrates, non-metal substrates based on semiconductor materials have received increasing attention in recent years owing to their unique physical, chemical, and optical properties. However, compared with noble metal substrates, most semiconductor substrates show weak Raman enhancement ability. Therefore, exploring effective strategies to improve the SERS sensitivity is an urgent task. Numerous reviews have outlined the research progress of semiconductor SERS substrates, which mainly focused on summarizing the material category of semiconductor substrates. However, reviews that systematically summarize the strategies for improving the SERS performance of semiconductor substrates are lacking. In this review, we comprehensively discuss the research on semiconductor SERS from the aspects of mechanism, materials, and modification. Firstly, the Raman enhancement mechanism of semiconductor substrates and the SERS-active materials are discussed. Then, we summarize several effective approaches to boost the SERS performance of semiconductor substrates. In conclusion, we propose some prospects for this field.

Surface quality of laser paint removal of marine steel: a comparative study using a Gaussian beam and a flat-top beam.

The spot mode has a great influence on the effect of laser paint removal, but it has not been clarified. This paper studies the influence of a Gaussian beam and a flat-top beam on surface quality. The results show that for the laser paint removal with the Gaussian beam, the surface hardness, corrosion resistance, and adhesion of marine steel improved significantly. The surface hardness increased by a factor of 20.8% compared to the original substrate, and the paint adhesion increased by 32.7%. For the flat-top beam, the surface quality of the substrate is unchanged, but the cleaning efficiency was observed to be 20% higher than that of the Gaussian beam. This paper can provide technical support for the control of surface cleaning quality in the laser paint removal process.

Precision Magnetic Field Sensing with Dual Multi-Wave Atom Interferometer.

Precision magnetic field measurement is widely used for practical applications, fundamental research, and medical purposes, etc. We propose a novel quantum magnetometer based on atoms' multi-wave (3-wave and 5-wave) Ramsey interference. Our design features high phase sensitivity and can be applied to in situ measurements of the magnetic field inside vacuum chambers. The final state detection is designed to be achieved by Raman's two-photon transition. The analytical solution for applicable interference fringe is presented. Fringe contrast decay due to atom temperature and magnetic field gradient is simulated to estimate reasonable experimental conditions. Sensitivity functions for phase noise and magnetic field noise in a multi-wave system are derived to estimate the noise level required to reach the expected resolution. The validity of the model, dual-channel features on bias estimation, and the quasi-non-destructive detection feature are discussed.

Sensitivity influencing factors during pesticide residue detection research via a terahertz metasensor.

Two metamaterial sensors were designed to test three pesticide residues. The influences of the metamaterial structure, the analyte composition and volume on the sensitivity have been studied. The metamaterial field-enhancement ability has an important influence on the sensitivity within the high-concentration range, while the coincidence between the metamaterial resonant frequency and the analyte fingerprint peak plays a dominant role within the low-concentration range. These findings allow us to better understand the process and find a way to improve the sensitivity.

Effects related to the temperature of atoms in an atom interferometry gravimeter based on ultra-cold atoms.

The temperature of atoms, coupled to several effects, plays an important role in high precision atom interferometry gravimeters. In this work, we present an ultra-cold 87Rb atom interferometry gravimeter, in which the atom source is produced by evaporative cooling in an all optical dipole trap to investigate the effects related to atom temperature. A condensate containing 4 × 104 atoms can be prepared within 3.2 s through an all-optical dipole trap composed of two reservoirs and a dimple. The fringe contrast of our atom interferometry gravimeter reaches up to 76(4)% due to the advantage of ultra-cold atom source even at a free evolution time of T=80 ms. A resolution of 6 µGal (1 µGal=1×10-8 m/s2) after 3000 s integration time with a sampling rate of 0.25 Hz is achieved in this atom gravimeter. The relationship between the fringe contrast and the atom temperature in the atom gravimeter is studied; in addition, the wavefront aberration effect in the atom gravimeter is also investigated by varying the temperature of atoms.

MARCKS on Tumor-Associated Macrophages is Correlated with Immune Infiltrates and Poor Prognosis in Hepatocellular Carcinoma.

BACKGROUND: Hepatocellular carcinoma is the fourth most common cause of cancer-related death. However, the cross-talk between tumor immune microenvironment and hepatocellular carcinoma (HCC) remains unclear. MATERIAL AND METHODS: We analyzed the expression of miR-143-3p in exosomes from different HCC cell lines. Differentially expressed genes (DEGs) in Tumor-associated macrophages (TAMs) co-cultured with HCC cell lines were overlapped with miR-143-3p target genes. We used the Oncomine, Kaplan-Meier plotter, and The Cancer Genome Atlas (TCGA) databases to assess Myristoylated alanine-rich C-kinase substrate (MARCKS) expression in various types of cancers. The relationship between patient clinicopathological characteristics and MARCKS expression level was identified using the Kaplan-Meier plotter database. Last, we analyzed how MARCKS expression correlated with immune infiltration makers using the TCGA database, Tumor IMmune Estimation Resource (TIMER), and Gene Expression Profiling Interactive Analysis (GEPIA). RESULTS: Exosomal miR-143-3p was elevated after IL-6 treatment in the HCC cell line. MARCKS, a target gene of miR-143-3p, was up-regulated in Tumor-associated macrophages co-cultured with high-metastatic-potential HCC cell line. MARCKS expression was identified as significantly correlated with outcome in multiple types of cancer, especially in HCC. High MARCKS expression level was associated with poorer overall survival (OS), Progress-free survival (PFS), and also with patient gender, race, hepatitis virus background, stage, grade, AJCC_T, and vascular invasion. MARCKS was positively associated with levels of T follicular helper cells (TFH) (R = .48, p < .001), T helper type 2 (Th2) cells (R = .47, p < .001), macrophages (R = .41, p ≤ .001), T helper cells (R = .40, p < .001), T helper type 1 (Th1) cells (R = .38, p < .001), T cells (R = .34, p < .001), NK CD56bright cells (R = .34, p < .001) and immature DC (iDC) (R = .33, p < .001), and negatively associated with levels of T helper 17 (Th17) cells. Also, MARCKS may influence the M2 polarization and immune escape. CONCLUSION: The present study suggests that MARCKS on TAMs is associated with poor prognosis and immune cell infiltration in HCC.

Position-guided Fano resonance and amended GaussAmp model for the control of slow light in hybrid graphene-silicon metamaterials.

Position-guided Fano resonance is observed in hybrid graphene-silicon metamaterials. An outstanding application of such resonance is slow-light metadevices. The maximum group delay is 9.73 ps, which corresponds to a group delay in free-space propagation of 2.92 mm. We employ a coupled oscillator model to illustrate anomalous transmission, where the intensity of the Fano peak increases with the Fermi level. Furthermore, we amend the GaussAmp model to serve as a suitable control equation for the group delay. The coefficient of correlation (R2) is as high as 0.99998, while the lowest values of the root-mean-square error and sum of squared errors are respectively 0.00421 and 0.00156. These results indicate that the amended GaussAmp model accurately controls the trend of the group delay. This work not only clarifies the mechanism of Fano resonance generation but also provides a promising platform for dynamically adjustable optical switches and multidimensional information sensors.

Distal C-terminus of Cav 1.2 is indispensable for the chondrogenic differentiation of rat dental pulp stem cells.

The α1 subunit (Cav1.2) of the L-type calcium channel (LTCC), which is presently existing in both excitatory cells and non-excitatory cells, is involved in the differentiation and proliferation of mesenchymal stem cells (MSCs). Dental pulp stem cells (DPSCs), MSCs derived from dental pulp, exhibit multipotent characteristics similar to those of MSCs. The aim of the present study was to examine the contribution of Cav1.2 and its distal C-terminus (DCT) to the commitment of rat DPSCs (rDPSCs) toward chondrocytes and adipocytes in vitro. The expression of Cav1.2 was obviously elevated in chondrogenic differentiation but did not differ significantly in adipogenic differentiation. The chondrogenic differentiation but not adipogenic of rDPSCs was inhibited by either blocking LTCC using nimodipine or knockdown of Cav1.2 via short hairpin RNA (shRNA). Overexpression of DCT rescued the inhibition by Cav1.2-shRNA during chondrogenic differentiation, indicating that DCT is essential for the chondrogenic differentiation of rDPSCs. However, the protein level of DCT decreased after chondrogenic differentiation in wild-type cells, and overexpression of DCT in rDPSCs inhibited the phenotype. These data suggest that DCT is indispensable for chondrogenic differentiation of rDPSCs but that superfluous DCT inhibits this process. Through the analysis of differentially expressed genes using RNA-seq data, we speculated that the regulation of DCT might be mediated by the mitogen-activated protein kinase/extracellular-regulated kinase and c-Jun N-terminal kinase signaling pathways, or Chondromodulin-1.

Effect of laser cleaning of carbon fiber-reinforced polymer and surface modification on chemical activity and bonding strength.

Bonding has been used to repair carbon fiber-reinforced polymer (CFRP) materials. However, research has shown that resin residue on the surface of CFRP can cause adhesion problems. Therefore, a reliable surface cleaning procedure is necessary to remove the resin residue before bonding. In this paper, the surface resin was removed by laser cleaning, while the surface properties of CFRP were improved. A pulsed laser cleaning experiment was designed to study the chemical activity and bonding strength of CFRP treated by laser with different laser power and scanning speed. The results showed that as the contact angle of the material surface decreased, chemical activity and adhesive properties were improved. The surface pretreated with laser power of 16 W (scanning speed of 1500 mm/s) had no resin residue and the best adhesive properties; the bonding strength was 1.6 times higher than that of the untreated surface, and the failure mode was dominated by a cohesive damage mode.

Theoretical study on femtosecond laser optical breakdown threshold in water mediated by aluminum nanoparticle coated with silica.

A strongly coupled finite element model of the optical breakdown during femtosecond laser pulse interaction, with different morphology of aluminum nanoparticles in water, was developed. This model provided new insight into the optical breakdown dependence on the nanoparticles' morphology and assembly. This model was used to theoretically investigate a 300 fs laser pulse interaction with uncoupled and plasmon coupled aluminum coated silica shell nanoparticles. This study revealed how the nanoparticles' one-dimensional assembly affected the optical breakdown threshold of its surrounding mediums. The optical breakdown threshold had much stronger dependence on the optical near-field enhancement than on the nanostructure's extinction cross-section. The maximum electric field that is outside of the aluminum nanoparticles, with 2 nm silica shell and 2 nm gap, was more than 4 times greater to the one inside of the aluminum nanoparticles. For dimer and trimer configuration, the calculated lattice cross-section temperatures at each breakdown threshold were below their melting point. It is suggested that water could be ionized by aluminum/silica (core/shell) nanostructure during femtosecond laser exposures without nanoparticles consumption. This model could increase understanding of the aluminum nanoparticle-mediated optical breakdown in water.

Tissue-specific significance of BAP1 gene mutation in prognostic prediction and molecular taxonomy among different types of cancer.

BAP1 is an emerging tumor suppressor whose inactivating mutations have been found to play critical roles in tumor development. This study was conducted to elucidate the potential value of BAP1 mutation in guiding prognostic prediction and clinical stratification. We conducted a comprehensive analysis of relevant studies from multiple databases, to determine the impact of BAP1 mutation on the overall survival and disease-free survival of patients in various cancers. A total of 2457 patients from 21 studies were included in the final analysis. Although the pooled results demonstrated that BAP1 mutation was a negative indicator of overall survival (hazard ratio = 1.73; 95% confidence interval = 1.23-2.42) and disease-free survival (hazard ratio = 2.25; 95% confidence interval = 1.47-3.45), this prognostic value was only applicable to uveal melanoma and clear cell renal cell carcinoma, but not to malignant pleural mesothelioma or cholangiocarcinoma. Consistently, BAP1 mutation was correlated with critical clinicopathological features only in uveal melanoma and clear cell renal cell carcinoma. In uveal melanoma, BAP1 mutation and SF3B1/EIF1AX mutations were negatively correlated, and BAP1-mutant tumors indicated significant worse prognosis than SF3B1/EIF1AX-mutant tumors ( p = 0.028). While in clear cell renal cell carcinoma, BAP1 mutation was mutually exclusive with PBRM1 mutations, and BAP1-mutant clear cell renal cell carcinomas also showed significantly worse prognosis than PBRM1-mutant clear cell renal cell carcinomas ( p = 0.001). Our study revealed a unique tissue-specific significance of BAP1 mutation in prognostic prediction among different types of cancer. Clinically, combining detection of BAP1 mutation and other driver mutations may further allow for a more precise molecular taxonomy to stratify patients into distinct subgroups in uveal melanoma and clear cell renal cell carcinoma.

[Analysis of iodine nutrition and thyroid function of adults in urban areas of Wuwei city Gansu province].

OBJECTIVE: To find out the iodine nutrition and thyroid function of adults in urban areas of Wuwei city Gansu province and to provide a basis for scientific iodine supplementation. METHODS: A cross-sectional survey was performed in 104 adults in Wuwei city form the April 2009 to January 2010. The morning blood samples and one urine samples selected randomly of different people were collected and three free triiodothyronine (FT3), free thyroid hormone (FT4), total triiodothyronine (TT3), total thyroxine (TT4), the thyroid-stimulating hormone (TSH), thyroglobulin antibodies (TGAb), thyroid microsomal antibodies (TMAb) in blood samples and iodine in urine samples were detected. RESULTS: The medians of urinary iodine were respectively 139.3 microg/L and 212.6 microg/L for male and female, female was significantly higher than male, there were statisticant differences (P < 0.05). TT3, TT4, FT4, FT3 and TSH's mean values were in the normal range, the abnormal ratio of TT3, TT4, FT3, FT4, TSH were respectively 1.9%, 1.0%, 3.8%, 1.9%, 16.3%. The positive rate of TGAb and TMAb in female were all higher than male, there were statisticant differences (P < 0.05). Subclinical hypothyroidism in all thyroid function disorders was most and accounted for 14.4% and female were all higher than male (P < 0.05). The survey were divided into iodine deficiency group, adequate iodine group, over adequate iodine group and iodine excess group for urinary iodine level. The abnormal ratio of TT3, TT4, FT3, FT4, TSH in four groups had no statistically differences, but the positive rate of TGAb and TMAb raised with increased urinary iodine level. Thyroid function disorders occurred in the other three groups except iodine deficiency group, and there were statisticant differences. CONCLUSION: Iodine nutrition level is appropriate for adults in urban areas, but the female was higher than male. Subclinical hypothyroidism in all thyroid function disorders was most, the positive rate of TGAb and TMAb raised with increased urinary iodine level, the risk of female suffered from thyroid disease was higher than male.

ZnO nanorods decorated with Ag nanoflowers as a recyclable SERS substrate for rapid detection of pesticide residue in multiple-scenes.

Pesticide residues threaten the ecological environment and human health. Therefore, developing high performance SERS substrate to achieve highly sensitive detection of pesticide residues is meaningful. In this study, based on the strategy of combining "hot spots" engineering and material hybridization, we construct a novel hybrid SERS substrate by depositing Ag nanoflowers (NFs) on ZnO nanorods (NRs). Benefiting from the synergistic effect of electromagnetic enhancement and charge transfer effect, the Ag NFs@ZnO NRs substrate exhibits a low detection limit (10-13 M) for crystal violet molecules. This SERS substrate has good uniformity with a relative standard deviation of 7.463 %. Besides, owning to the photocatalytic property of ZnO NRs, the hybrid substrate can degrade probe molecules after SERS detection and realize recyclability. As a demonstration, we employed our SERS substrate for the trace detection of pesticide residues on apple surface and in river water. This study provides a new idea for improving the SERS performance of hybrid substrates.

Four-Dimensional Micro/Nanorobots via Laser Photochemical Synthesis towards the Molecular Scale.

Miniaturized four-dimensional (4D) micro/nanorobots denote a forerunning technique associated with interdisciplinary applications, such as in embeddable labs-on-chip, metamaterials, tissue engineering, cell manipulation, and tiny robotics. With emerging smart interactive materials, static micro/nanoscale architectures have upgraded to the fourth dimension, evincing time-dependent shape/property mutation. Molecular-level 4D robotics promises complex sensing, self-adaption, transformation, and responsiveness to stimuli for highly valued functionalities. To precisely control 4D behaviors, current-laser-induced photochemical additive manufacturing, such as digital light projection, stereolithography, and two-photon polymerization, is pursuing high-freeform shape-reconfigurable capacities and high-resolution spatiotemporal programming strategies, which challenge multi-field sciences while offering new opportunities. Herein, this review summarizes the recent development of micro/nano 4D laser photochemical manufacturing, incorporating active materials and shape-programming strategies to provide an envisioning of these miniaturized 4D micro/nanorobots. A comparison with other chemical/physical fabricated micro/nanorobots further explains the advantages and potential usage of laser-synthesized micro/nanorobots.

[Analysis on iodine nutritional status and thyroid function in pregnant women].

OBJECTIVE: To investigate the iodine nutritional status and thyroid function of pregnant women during different periods of pregnancy, to provide evidence for guiding iodine supplementation for them. METHODS: A cross-sectional survey was performed in 90 pregnant women in Wuwei City from April 2009 to January 2010. The morning blood samples and random urine samples were collected, and the thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), free thyroid hormone (FT4), thyroglobulin antibodies (TGAb), thyroid microsomal antibodies (TMAb) in blood samples and iodine in urine samples were detected. RESULTS: The medians of urinary iodine were 231.49, 158.25 and 328.35 microg/L for women in early, middle and late period of pregnancy, The ratio of urinary iodine below 150 microg/L were 39.29%, 45.16% and 25.81%, respectively. The FT3, FT4 levels in the first trimester were higher than those in the third trimester (P < 0.05) and TSH level was increased, but no significant difference (P > 0.05). The positive rate of TGAb and TMAb antibody of pregnant women in different period of time were not significantly different (P > 0.05). The incidence of thyroid function disorder was significantly different in different gestation periods. CONCLUSION: Generally, the iodine nutritional status of these pregnant women was appropriate, but there was a tendency towards hypothyroid in some women. Monitoring urinary iodine and thyroid function in pregnant women should be carried out regularly.