Citrus Huanglongbing detection and semi-quantification of the carbohydrate concentration based on micro-FTIR spectroscopy.

Citrus Huanglongbing (HLB) is nowadays one of the most fatal citrus diseases worldwide. Once the citrus tree is infected by the HLB disease, the biochemistry of the phloem region in midribs would change. In order to investigate the carbohydrate changes in phloem region of citrus midrib, the semi-quantification models were established to predict the carbohydrate concentration in it based on Fourier transform infrared microscopy (micro-FTIR) spectroscopy coupled with chemometrics. Healthy, asymptomatic-HLB, symptomatic-HLB, and nutrient-deficient citrus midribs were collected in this study. The results showed that the intensity of the characteristic peak varied with the carbohydrate (starch and soluble sugar) concentration in citrus midrib, especially at the fingerprint regions of 1175-900 cm-1, 1500-1175 cm-1, and 1800-1500 cm-1. Furthermore, semi-quantitative prediction models of starch and soluble sugar were established using the full micro-FTIR spectra and selected characteristic wavebands. The least squares support vector machine regression (LS-SVR) model combined with the random frog (RF) algorithm achieved the best prediction result with the determination coefficient of prediction ([Formula: see text]) of 0.85, the root mean square error of prediction (RMSEP) of 0.36%, residual predictive deviation (RPD) of 2.54, and [Formula: see text] of 0.87, RMSEP of 0.37%, RPD of 2.76, for starch and soluble sugar concentration prediction, respectively. In addition, multi-layer perceptron (MLP) classification models were established to identify HLB disease, achieving the overall classification accuracy of 94% and 87%, based on the full-range spectra and the optimal wavenumbers selected by the random frog (RF) algorithm, respectively. The results demonstrated that micro-FTIR spectroscopy can be a valuable tool for the prediction of carbohydrate concentration in citrus midribs and the detection of HLB disease, which would provide useful guidelines to detect citrus HLB disease.

The treatment of integrated traditional Chinese and Western medicine to cure severe immune thrombocytopenia in a patient in a minimally conscious state: a case report.

Immune thrombocytopenia is a common complication in patients in a minimally conscious state (MCS). MCS patients are prone to pulmonary infection for the reasons of long-term bed rest and tracheotomy etc., which leads to frequent immune thrombocytopenia. At present, there is no specific treatment for immune thrombocytopenia. Moreover, the cost of routine treatment is high, and clinicians need to consider different drug combinations, side effects, and the risk of drug dependence when selecting treatments. Here, we report a case of a patient in a MCS who developed immune thrombocytopenia after tracheotomy and long-term bed laying in October 2015. The patient's platelet count declined continuously, and by December 2015, she was in a critical condition, with a platelet count of less than 20×109/L. The patient firstly received routine treatment, however, this could only temporarily prevent the drop in platelets. Following a series of explorations, the patient was treated with a combination of traditional Chinese and Western medicine, which included treatment and preventive measures. For treatment, the patient was given roxithromycin dispersible administration tablets and a self-made preparation of peanut red skin, which could quickly cure the immune thrombocytopenia. Preventive measures included the addition of ursodeoxycholic acid capsules, silybin capsules, and a traditional Chinese medicine preparation. As shown by laboratory examination results, the patient's platelet count has stayed around a normal level since March 2016, and she now has normal liver and kidney function. This outcome evidence that combined traditional Chinese and Western medicine could effectively cure immune thrombocytopenia and prevent its recurrence. Moreover, the cost of the treatment was lower and there were fewer side effects than routine treatment, and at the same time, the method of treatment was simple and convenient. Our practical experience may provide a valuable clue for the treatment of immune thrombocytopenia.

Zeolitic imidazolate framework-8 (ZIF-8)-coated In2O3 nanofibers as an efficient sensing material for ppb-level NO2 detection.

The development of NO2 gas sensors is of great importance for air quality monitoring and human health. In this work, In2O3 and zeolitic imidazolate framework-8 (ZIF-8) heterostructures were synthesized and designed as efficient sensing materials for NO2 detection. The ZIF-8 nanocrystals were uniformly deposited on In2O3 nanofibers (NFs) by using a self-template strategy, where In2O3/ZnO NFs act as the source of Zn2+ for the formation of ZIF-8 and as the template. By tuning the amount of Zn2+ in the composite NFs, different morphologies from In2O3 NFs with minimal ZIF-8 loading to an In2O3/ZIF-8 core-shell complex were obtained. The optimized In2O3/ZIF-8 NFs show a remarkably high response to 1 ppm NO2 (Rg/Ra = 16.4) and enhanced humidity resistance due to the hydrophobicity of ZIF-8 in comparison with those of the pristine In2O3 NF sensor (Rg/Ra = 4.9) at 140 °C. The gas sensing mechanism of In2O3/ZIF-8, which is based on electron transduction, surface chemistry, and the functional interface between the loaded ZIF-8 and In2O3 matrix, was proposed. Additionally, the large number of pores, which were formed by the in situ conversion of ZnO grains in the matrix, ensures that all parts of the In2O3 NFs are accessible to gases. This facile strategy paves the way for the design of metal oxide/MOF complex architectures with tunable metal centers for various applications, including gas sensing.

Ultrafast Response Polyelectrolyte Humidity Sensor for Respiration Monitoring.

Respiration monitoring is important for evaluating human health. Humidity sensing is a promising way to establish a relationship between human respiration and electrical signal. This work describes polymer humidity sensors with ultrafast response for respiration monitoring. The humidity-sensitive polyelectrolyte is in situ cross-linked on the substrate printed with interdigitated electrodes by a thiol-ene click reaction. The polyelectrolyte humidity sensor shows rapid water adsorption/desorption ability, excellent stability, and repeatability. The sensor with ultrafast response and recovery (0.29/0.47 s) when changing humidity between 33 and 95% shows good application prospects in breath monitoring and touchless sensing. Different respiration patterns can be distinguished, and the breath rate/depth of detection subjects can also be determined by the sensor. In addition, the obtained sensor can sense the skin evaporation in a noncontact way.

NiFe2O4 Nanofibers: Morphology, Lithium Storage and Photocatalytic Properties.

One dimensional (1D) NiFe2O4 nanofibers have been successfully fabricated using single-nozzle electrospinning technique and subsequent calcination process through adjusting heat-treatment parameters. The calcination procedure plays a key role for the formation of nanofibers with different morphologies. The lithium storage properties of NiFe2O4 nanofibers were evaluated by galvanostatic cycling studies in half-cell configuration. Furthermore, their photocatalytic property under vis-light irradiation with H2O2 addition is investigated at room temperature. As-synthesized nanofibers with regular 1D nanostructure with large surface area and high crystallinity calcined at 600 °C exhibited fine lithium storage with excellent cycling and rate performance, as well as excellent photocatalytic performance with 97% degradation proportion of methylene blue after 30 min. This is ascribed to NiFe2O4 absorbed the photon energy and generated electron-hole pairs under vis-light irradiation.

Nanostructured TiO2 Films Attached CdSe QDs Toward Enhanced Photoelectrochemical Performance.

TiO2 films consisted of small nanoparticles were fabricated via a spinning coating method on fluorine doped in tin oxide (FTO) slide glass. After calcination, the films were subsequently sensitized by CdSe quantum dots (QDs) using mercaptopropionic acid (MPA) as a bifunctional surface modifier. Upon UV light irradiation, CdSe QDs inject electrons into TiO2 nanoparticles, thus resulting in the generation of photocurrent in QD-sensitized solar cell. The results indicate that TiO2 films sensitized by CdSe QDs have achieved 1.5-fold enhancement in photocurrent compared with pure TiO2 films, indicating that CdSe QDs can improve the photocurrent by promoting the separation of photoinduced charge carriers. In addition, the photocurrent enhances as the thickness of TiO2 films increased. Such improved photoelectrochemical performance is ascribed to the basis of improved interfacial charge transport of the TiO2-CdSe composite films. Combining QDs on TiO2 thin films is a promising and effective way to enhance the photoelectrochemical performance, which is important in QD-sensitized solar cell application.

Photodegradation of Mercaptopropionic Acid- and Thioglycollic Acid-Capped CdTe Quantum Dots in Buffer Solutions.

CdTe quantum dots (QDs) were synthesized by 3-mercaptopropionic acid (MPA) and thioglycollic acid (TGA) as capping agents. It is confirmed that TGA and MPA molecules were attached on the surface of the QDs using Fourier transform infrared (FT-IR) spectra. The movement of the QDs in agarose gel electrophoresis indicated that MPA-capped CdTe QDs had small hydrodynamic diameter. The photoluminescence (PL) intensity of TGA-capped QDs is higher than that of MPA-capped QDs at same QD concentration because of the surface passivation of TGA. To systemically investigate the photodegradation, CdTe QDs with various PL peak wavelengths were dispersed in phosphate buffered saline (PBS) and Tris-borate-ethylenediaminetetraacetic acid (TBE) buffer solutions. It was found that the PL intensity of the QDs in PBS decreased with time. The PL peak wavelengths of the QDs in PBS solutions remained unchanged. As for TGA-capped CdTe QDs, the results of PL peak wavelengths in TBE buffer solutions indicated that S(2-) released by TGA attached to Cd(2+) and formed CdS-like clusters layer on the surface of aqueous CdTe QDs. In addition, the number of TGA on the CdTe QDs surface was more than that of MPA. When the QDs were added to buffer solutions, agents were removed from the surface of CdTe QDs, which decreased the passivation of agents thus resulted in photodegradation of CdTe QDs in buffer solutions.