High precision even-power phase modulation method for a self-mixing displacement sensor under the weak feedback regime.

A novel method called even-power phase modulation is proposed in a self-mixing displacement sensor to improve measuring accuracy, to the best of our knowledge, which is realized by combining the even-power fast algorithm with the sinusoidal phase-modulation method. By performing the even-power fast algorithm in the self-mixing interference system, the spectrum of harmonic components is broadened. In this case, the extracted first and second harmonic components in the frequency domain contain rich information, and the displacement of the target can be accurately reconstructed. The principle and signal processing approach are introduced in detail, and the simulation results show that the reconstruction error can be effectively reduced compared with the electro-optic modulator phase modulation method. A series of experiments at different vibration amplitudes is conducted to confirm the feasibility and effectiveness of the method. An amplitude of 120 nm is proved to be measurable, and the absolute error is 10 nm, which shows great potential in the field of non-contact nanometer vibration measurement sensors.

A Michael addition reaction-based fluorescent probe for malononitrile detection and its applications in aqueous solution, living cells and zebrafish.

It is highly desirable to detect malononitrile in organisms and human bodies owning to its inherent toxicity. With dicyanovinyl as the recognition site, a Michael addition reaction-based fluorescent probe Hcy-DCV was developed for malononitrile detection. A notable advantage of this probe is that it responds quickly to malononitrile without any additive to speed the sensing reaction. It has a good water solubility and the detection limit was determined to be 6.92 ppb in 100% aqueous solution. In particular, Hcy-DCV exhibited good selectivity towards malononitrile over other interfering substances including hydrazine and other active methylene compounds. The probe was applied successfully to quantitate malononitrile in pure water with satisfying recovery and relative standard deviation. Additionally, the ability of visualizing malononitrile by using probe-coated strip papers was displayed, which may facilitate the on-site detection of malononitrile. Moreover, the bioimaging of malononitrile in living H1975 cells and zebrafish larvae was also demonstrated. All the experimental results suggested the potential of Hcy-DCV for practical detection of malononitrile in both environmental and biological samples.

The synthesis and bioimaging of a biocompatible hydrogen sulfide fluorescent probe with high sensitivity and selectivity.

Hydrogen sulfide (H2S), a well-known poisonous gas, has been recognized as a critical endogenous gas transmitter in the past decade. To provide a quick and efficient detection method for hydrogen sulfide, a novel fluorescent probe DCI-NCN was designed based on an isophoronitrile scaffold featured with the cyanoxy group as the detection group. DCI-NCN shows promising results including high selectivity, high sensitivity, good linear relationship and pH stability in vitro. In addition, good biosystem imaging performance of DCI-NCN is observed in Kunming mice.

Improved method for damping coefficient measurement based on spectral analysis of a self-mixing signal.

In this paper, the self-mixing interference subject to weak optical feedback has been used to measure the damping vibration. By analyzing the spectrum of the signal, the damping coefficient can be extracted precisely from the nth-order Bessel functions, which are determined by the dominant harmonic order of the frequency spectrum. Theoretical derivation and signal processing are presented. Four kinds of vibrating targets with different damping coefficients are measured. Experimental results show that standard deviation and root mean square error of data are less than 0.2 and 0.1, respectively, which means fitted values are stable as well as having a very high fitting precision.

Highly selective recognition of L-phenylalanine with molecularly imprinted polymers based on imidazolyl amino acid chiral ionic liquid.

Several amino acid chiral ionic liquids were introduced as functional monomers to prepare molecularly imprinted polymers for specific recognition of L-phenylalanine. Among them, the imprinted polymers L-Phe@MIPs based on [ViImC3][L-Pro] showed the best selective recognition ability for L-phenylalanine. A series of experiments such as dynamic adsorption, static adsorption, and competitive adsorption were conducted to investigate the specific recognition ability and adsorption capacity of the L-Phe@MIPs. It is found that the adsorption efficiency to L-phenylalanine on L-Phe@MIPs was 3.11 times higher than that to D-phenylalanine. All the results demonstrated that the L-Phe@MIPs possessed good recognition and relatively high adsorption efficiency for L-phenylalanine. Besides, the recovery of L-phenylalanine was above 98%, and the L-Phe@MIPs exhibited good reusability.

Power-ratio tunable dual-wavelength laser using linearly variable Fabry-Perot filter as output coupler.

For a linearly variable Fabry-Perot filter, the peak transmission wavelengths change linearly with the transverse position shift of the substrate. Such a Fabry-Perot filter is designed and fabricated and used as an output coupler of a c-cut Nd:YVO4 laser experimentally in this paper to obtain a 1062 and 1083 nm dual-wavelength laser. The peak transmission wavelengths are gradually shifted from 1040.8 to 1070.8 nm. The peak transmission wavelength of the Fabry-Perot filter used as the output coupler for the dual-wavelength laser is 1068 nm and resides between 1062 and 1083 nm, which makes the transmissions of the desired dual wavelengths change in opposite slopes with the transverse shift of the filter. Consequently, powers of the two wavelengths change in opposite directions. A branch power, oppositely tunable 1062 and 1083 nm dual-wavelength laser is successfully demonstrated. Design principles of the linear variable Fabry-Perot filter used as an output coupler are discussed. Advantages of the method are summarized.

Enantioselective Alkyne Addition to Aliphatic, Aromatic, and Vinyl Aldehydes Using Zn, (i)PrI, H8BINOL, and Ti(O(i)Pr)4.

A new catalytic system based on the readily available Zn, (i)PrI, H8BINOL, and Ti(O(i)Pr)4 has been developed which avoids the use of pyrophoric ZnEt2. It can effectively catalyze the reaction of various terminal alkynes with aromatic, aliphatic, and vinyl aldehydes to generate chiral propargylic alcohols at room temperature with up to 98% yield and 98% enantiomeric excess. This new system signifciantly expands the substrate scope of the previously reported system using Zn, EtI, BINOL, and Ti(O(i)Pr)4.

Fast detection of sodium dithionite in sugar using a xanthylium-based fluorescent probe.

Dithionite remained in the foodstuff may pose a great threat to the health of consumers. Three xanthylium-based probes were synthesized and their responses to dithionite were explored. Probe SH-1 could respond to dithionite selectively in PBS buffer (15% DMSO, 10 mM, pH = 7.4). Upon the addition of dithionite, the fluorescent emission of SH-1 at 684 nm dropped quickly (within 10 s) and the fluorescence decline was proportional to the concentration of dithionite (0-7.0 µM). The limit of detection was determined to be 0.139 µM. Then, the sensing mechanism was tentatively presented and the structure of resulted adduct (SH-1-SO3-) which was the reaction product of SH-1 and dithionite via a Micheal addition reaction followed by an oxidation reaction was verified. Moreover, white granulated sugar was subjected to the standard spike experiments and the results demonstrated a great potential of SH-1 for the quantitative monitoring of dithionite in foodstuffs.

Quantification and visual inspection of adipic dihydrazide in textile using a xanthylium-based ratiometric fluorescent probe.

Residual adipic dihydrazide (ADH) in textiles may react with formaldehyde to form hydrazone, which is a source of the formaldehyde pollutant indoors. In this paper, a xanthylium-based ratiometric fluorescent probe SH-Py was developed for ADH detection. The emission of SH-Py at 680 nm decreased, whereas that at 463 nm increased upon the addition of ADH in pure DMSO. The LOD was as low as 24.5 nM, and the possible sensing mechanism is presented. Good recoveries were observed in the standard recovery experiments of SH-Py for ADH detection in textiles. Moreover, the visualization of ADH in textiles was successfully achieved by spraying the probe solution and then inspecting it under a UV lamp. Additionally, SH-Py has the potential to quantify other aliphatic hydrazides in various samples.

Visual inspection of acidic pH and bisulfite in white wine using a colorimetric and fluorescent probe.

The acidic pH and total amount of SO2 are both important quality control indexes of wine, but conventional detection techniques depend heavily on specialized instrument and professional staff, thus are not available to general customers. In this paper, a hemicyanine-based colorimetric and fluorescent probe Hcy-Py was designed and synthesized. It responded to bisulfite selectively with a LOD of 0.68 µM and responded to proton with a pKa of 3.78. Upon the treatment of solutions with different pH values and concentrations of bisulfite, the probe-loaded paper strips displayed distinct color changes under both natural light and UV lamp. When a real white wine sample was subjected to the paper strip experiment, pH as well as bisulfite concentration could be determined by naked-eye quickly and conveniently, thus a visual detection of acidic pH and bisulfite in white wine without involving any sophisticated instrument or professional skill was successfully demonstrated.

A fluorescent probe for alkylating agents and its quantification of triflate as a genotoxic impurity.

The responses of a reaction-based fluorescent probe BI-Py towards alkyl halide, epoxide, carbonate, sulfate, sulphonate and triflate were evaluated and the probe achieved selective detection of ethyl triflate in acetonitrile with a LOD of 1.08 µM. BI-Py exhibited great potential for detecting triflate as a genotoxic impurity in drug substances.

Clinical application of three-dimensional T1-weighted BrainVIEW in magnetic resonance imaging of cerebral venous thrombosis: a case report and literature review.

To date, there is no clinical scoring system or laboratory indicator that can rule out cerebral venous thrombosis (CVT) or provide diagnostic proof for evaluating post-treatment thrombosis recanalization during follow-up. We therefore explored an imaging method for quantitative assessment of CVT and assessed thrombotic changes during follow-up. A patient presented with severe posterior occipital distension extending to the top of the forehead and an elevated plasma D-dimer (DD2) level. Computed tomography and pre-contrast-enhanced magnetic resonance imaging revealed only a small amount of cerebral hemorrhage. Three-dimensional (3D) T1-weighted (T1W) BrainVIEW pre-contrast-enhanced magnetic resonance scanning showed subacute thrombosis in the venous sinus, and the post-contrast-enhanced scan combined with volume rendering reconstruction showed cerebral thrombosis of the venous sinus and allowed for measurement of the thrombus volume. On days 30 and 60 of post-treatment follow-up, post-contrast-enhanced scans showed progressive reduction of the thrombus volume as well as recanalization and fibrotic flow voids in the chronic thrombosis. 3D T1W BrainVIEW was helpful to observe the size of the thrombi and the situation of venous sinus recanalization during the follow-up after clinical treatment of CVT. This technique can reflect the imaging manifestations of CVT throughout the whole process to guide clinical treatment decisions.

A study on the differential of solid lung adenocarcinoma and tuberculous granuloma nodules in CT images by Radiomics machine learning.

To study the classification efficiency of using texture feature machine learning method in distinguishing solid lung adenocarcinoma (SADC) and tuberculous granulomatous nodules (TGN) that appear as solid nodules (SN) in non-enhanced CT images. 200 patients with SADC and TGN who underwent thoracic non-enhanced CT examination from January 2012 to October 2019 were included in the study, 490 texture eigenvalues of 6 categories were extracted from the lesions in the non-enhanced CT images of these patients for machine learning, the classification prediction model is established by using relatively the best classifier selected according to the fitting degree of learning curve in the process of machine learning, and the effectiveness of the model was tested and verified. The logistic regression model of clinical data (including demographic data and CT parameters and CT signs of solitary nodules) was used for comparison. The prediction model of clinical data was established by logistic regression, and the classifier was established by machine learning of radiologic texture features. The area under the curve was 0.82 and 0.65 for the prediction model based on clinical CT and only CT parameters and CT signs, and 0.870 based on Radiomics characteristics. The machine learning prediction model developed by us can improve the differentiation efficiency of SADC and TGN with SN, and provide appropriate support for treatment decisions.

Synthesis and evaluation of 2-[2-(phenylthiomethyl)-1H-benzo[d] imidazol-1-yl)acetohydrazide derivatives as antitumor agents.

A novel class of acetylhydrazone derivatives (5a-x) containing 2-(phenylthiomethyl)-1H-benzo-[d]-imidazole moieties are synthesizer, and their antitumor activities against A549, HCT116, HepG2, PC-9, and A375 were determined by the MTT assay. Among them are N-(2,4-dihydroxybenzylidene)-2-(2-(phenylthiomethyl)-1H-benzo[d]-imidazol-1-yl)acetohydrazide (5a) and N-(5-bromo-2-hydroxy-benzylidene)-2-(2-(phenylthiomethyl)-1H-benzo[d]-imidazol-1-yl)acetohydrazide (5d) which displayed excellent cancer inhibitory activity against the tested cancer cells (IC(50) 4-17 µM), compared with 5-FU and SU11248. The others have moderate to weak inhibitory activity against the tested cancer cell lines.

2-Chloro-N-(4-chloro-3-iodo-phen-yl)-4-(methyl-sulfon-yl)benzamide.

In the title compound, C(14)H(10)Cl(2)INO(3)S, the dihedral angle between the benzene rings is 52.13 (10)°. In the crystal, the components are linked by pairs of N-H⋯O(sulfon-yl) hydrogen bonds into centrosymmetric dimers.

Comparative studies on the absorption and fluorescence responses of hemicyanine to HSO3-, CN-, HS- and ClO.

A fluorescent probe Hcy-Im bearing an indolium-hemicyanine structure was designed and synthesized to compare its responses to four anions, namely HSO3-, CN-, HS- and ClO-. The results disclosed that Hcy-Im reacted with all these four anions in 5% DMSO-PBS buffer with different speeds and spectral changes. Hcy-Im responded to HSO3- markedly quicker than CN- and HS-, and it responded to CN- a little quicker than HS- while the response to ClO- was much slower than the other three anions. The detection limits for these four anions were calculated to be 0.15 µM, 1.32 µM, 2.07 µM and 2.29 µM, respectively. The characteristic conjugated CN+ and CC bonds in Hcy-Im were responsible for the responses towards these four anions via a Michael addition-rearrangement reaction, a 1, 2-addition reaction or an oxidation reaction. These different sensing mechanisms were verified by 1HNMR and HRMS. Thus, it could be inferred that hemicyanine-based fluorescent probe could detect HSO3- sensitively and selectively while the interference of HSO3- should not be neglected when it was used for the detection of CN-, HS- and ClO-. Moreover, as HSO3-, HS- and ClO- are anions endogenously generated in human bodies, enough attention should be paid to the presence of physiological level of these three anions in certain tissues when hemicyanine-based fluorescent probe is applied for the detection of biorelevant analytes in biological samples.

A colorimetric and fluorometric probe for phenylhydrazine and its application in real samples.

A fluorescent probe for phenylhydrazine detection was developed with aldehyde as the recognition group and good selectivity towards phenylhydrazine over hydrazine, hydroxylamine and other amines was observed. Its application in real water samples and fast visualization of phenylhydrazine using a probe-loaded paper strip were demonstrated.

Heterogeneity Analysis of Chest CT Predict Individual Prognosis of COVID-19 Patients.

BACKGROUND: Ground-glass Opacity (GGO) and Consolidation Opacity (CLO) are the common CT lung opacities, and their heterogeneity may have potential for prognosis ofcoronavirus disease-19 (COVID-19) patients. OBJECTIVE: This study aimed to estimate clinical outcomes in individual COVID-19 patients using histogram heterogeneity analysis based on CT opacities. METHODS: 71 COVID-19 cases' medical records were retrospectively reviewed from a designated hospital in Wuhan, China, from January 24th to February 28th at the early stage of the pandemic. Two characteristic lung abnormity opacities, GGO and CLO, were drawn on CT images to identify the heterogeneity using quantitative histogram analysis. The parameters (mean, mode, kurtosis, and skewness) were derived from histograms to evaluate the accuracy of clinical classification and outcome prediction. Nomograms were built to predict the risk of death and median length of hospital stays (LOS), respectively. RESULTS: A total of 57 COVID-19 cases were eligible for the study cohort after excluding 14 cases. The highest lung abnormalities were GGO mixed with CLO in both the survival populations (26 in 42, 61.9%) and died population (10 in 15, 66.7%). The best performance heterogeneity parameters to discriminate severe type from mild/moderate counterparts were as follows: GGO_skewness: specificity= 66.67%, sensitivity=78.12%, AUC=0.706; CLO_mean: specificity=70.00%, sensitivity= 76.92%, and AUC=0.746. Nomogram based on histogram parameters can predict the individual risk of death and the prolonged median LOS of COVID-19 patients. C-indexes were 0.763 and 0.888 for risk of death and prolonged median LOS, respectively. CONCLUSION: Histogram analysis method based on GGO and CLO has the ability for individual risk prediction in COVID-19 patients.

Case Report: Recombinant Human Endostatin Plus Chemotherapy for Epidermal Growth Factor Receptor-Negative Miliary Lung Adenocarcinoma.

Except for the traditional chemotherapy, few treatments strategy about miliary intrapulmonary carcinomatosis (MIPC) have been reported in the existing literature. In this report, we primarily discussed the possible etiology and the potentially effective treatment options for a patient with MIPC who benefited from combined treatment. A nonsmoking woman was diagnosed with MIPC at an advanced stage. Gene detection showed an EGFR negative status. She accepted first-line chemotherapy with pemetrexed and cisplatin, and the tumor progressed. Next, PD-1 inhibitors plus pemetrexed and cisplatin were administered, and the tumor remained uncontrolled. After two cycles of recombinant human endostatin plus second-line chemotherapy, the numerous pulmonary nodules had all nearly completely disappeared, while an accentuated decrease in the primary tumor volume was observed. Moreover, biochemical markers, including the patient's tumor markers, also trended toward normal. This report describes the first case of a MIPC patient who significantly responded to antiangiogenic therapy combined with chemotherapy. Anti-angiogenic therapy may be a possible strategy for the EGFR-negative lung adenocarcinoma population.

Analysis of the Causes of Solitary Pulmonary Nodule Misdiagnosed as Lung Cancer by Using Artificial Intelligence: A Retrospective Study at a Single Center.

Artificial intelligence (AI) adopting deep learning technology has been widely used in the med-ical imaging domain in recent years. It realized the automatic judgment of benign and malig-nant solitary pulmonary nodules (SPNs) and even replaced the work of doctors to some extent. However, misdiagnoses can occur in certain cases. Only by determining the causes can AI play a larger role. A total of 21 Coronavirus disease 2019 (COVID-19) patients were diagnosed with SPN by CT imaging. Their Clinical data, including general condition, imaging features, AI re-ports, and outcomes were included in this retrospective study. Although they were confirmed COVID-19 by testing reverse transcription-polymerase chain reaction (RT-PCR) with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), their CT imaging data were misjudged by AI to be high-risk nodules for lung cancer. Imaging characteristics included burr sign (76.2%), lobulated sign (61.9%), pleural indentation (42.9%), smooth edges (23.8%), and cavity (14.3%). The accuracy of AI was different from that of radiologists in judging the nature of be-nign SPNs (p < 0.001, κ = 0.036 < 0.4, means the two diagnosis methods poor fit). COVID-19 patients with SPN might have been misdiagnosed using the AI system, suggesting that the AI system needs to be further optimized, especially in the event of a new disease outbreak.