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Zeolitic imidazolate frameworks (ZIFs) can separate olefins from paraffin with very little energy consumption, which is critical for the chemical industry. They can form a large diversity of polymo...

Artificial Neural Network (ANN) models have been extensively applied in the prediction of water resource variables, and Geographical Information System (GIS) includes powerful functions to visualize spatial data. In order to provide an efficient tool for environmental assessment and management that combines the advantages of these two modules, a GIS-based ANN water quality prediction system was developed in the present study. The ANN module and ArcGIS Engine module, along with a dynamic database, were imbedded in the system, which integrates water quality prediction via the ANN model and spatial presentation of the model results. The structure of the ANN model could be modified through the graphical user interface to optimize the model performance. The developed system was applied to a real case study for the prediction of the total phosphorus concentration in the Lake Champlain area. The prediction results were verified with the monitoring data, and the performance of the developed model was further evaluated through graphical techniques and quantitative statistical methods. Overall, the developed system provided satisfactory prediction results, and spatial distribution maps of the predicted results were obtained, which coincided with the monitored values. The developed GIS-based ANN water quality prediction system could serve as an efficient tool for engineers and decision makers.

We present a family of digital polymerase chain reaction (dPCR) chips made of silicon that are (9 × 9) mm2 in size, have a unique layout design, and have between 26,448 and 1,656,000 reaction wells. The chip layout was split into six fields sized 4200 × 2785 μm2 that contain reaction wells with a gap of a few μm separating the fields from each other. We also developed a universal fluorescence imaging method capable of processing images from those chips. It comprised automatic image acquisition, image stitching, alignment mark registration, rotation correction, determination of reaction wells’ positions, and result processing. The chip design, with fully automated image processing, provided a fast and reliable system for the absolute quantitative analysis of dPCR. Combined with ease-of-use, this family of dPCR chips offers a pathway to enable fast and affordable digital microfluidic diagnostic applications.

In this paper, we use the factor analysis model, and get the prediction function of the solvency of insurance companies. In order to verify the feasibility of the model, we have adopted Accumulated Local Effects Plot. It is proved that the solvency of an insurance company is positively correlated with its monetary funds, term deposits and owner's equity, negatively related to its own liabilities, and that the two indicators of monetary capital and insurance company liabilities are factors that have a high marginal contribution to predicting the solvency of insurance companies.

PCR has become one of the most valuable techniques currently used in bioscience, diagnostics and forensic science. Here we review the history of PCR development and the technologies that have evolved from the original PCR method. Currently, there are two main areas of PCR utilization in bioscience: high-throughput PCR systems and microfluidics-based PCR devices for point-of-care (POC) applications. We also discuss the commercialization of these techniques and conclude with a look into their modifications and use in innovative areas of biomedicine. For example, real-time reverse transcription PCR is the gold standard for SARS-CoV-2 diagnoses. It could also be used for POC applications, being a key component of the sample-to-answer system.

Nucleic acid amplification for the detection of infectious diseases, food pathogens, or assessment of genetic disorders require a laboratory setting with specialized equipment and technical expertise. Isothermal deoxyribonucleic acid amplification methods, such as loop-mediated isothermal amplification (LAMP), exhibit characteristics ideal for point-of-care (POC) applications, since their instrumentation is simpler in comparison with the standard method of polymerase chain reaction. Other key advantages of LAMP are robustness and the production of pyrophosphate in the presence of the target gene, enabling to detect the reaction products using the naked eye. Polymerase inhibitors, presented in clinical samples, do not affect the amplification process, making LAMP suitable for a simple sample-to-answer diagnostic systems with simplified sample preparation. In this review, we discuss the trends in miniaturized LAMP techniques, such as microfluidic, paper-based, and digital with their advantages and disadvantages, especially for POC applications alongside our opinion of the future development of miniaturized LAMP., Highlights • Introduction of loop mediated isothermal amplification (LAMP) and its principle. • Classical microfluidics-based LAMP for DNA/RNA detection. • Paper-based LAMP. • Microfluidic-based digital LAMP. • Future of microfluidic LAMP development.

Microfluidic devices typically require complex shapes such as funnels, spirals, splitters, channels with different widths, or customized objects of arbitrary complexity with a smooth transition between these elements. Device layouts are generally designed by software developed for the design of integrated circuits or by general computer-aided design drawing tools. Both methods have their limitations, making these tasks time consuming. Here, a script-based, time-effective method to generate the layout of various microfluidic chips with complex geometries is presented. The present work uses the nanolithography toolbox (NT), a platform-independent software package, which employs parameterized fundamental blocks (cells) to create microscale and nanoscale structures. In order to demonstrate the functionality and efficiency of the NT, a few classical microfluidic devices were designed using the NT and then fabricated in glass/silicon using standard microfabrication techniques and in poly(dimethylsiloxane) using soft lithography as well as more complex techniques used for flow-through calorimetry. In addition, the functionality of a few of the fabricated devices was tested. The powerful method proposed allows the creation of microfluidic devices with complex layouts in an easy way, simplifying the design process and improving design efficiency. Thus, it holds great potential for broad applications in microfluidic device design.

N ions implantation induced quantum well intermixing in GaInP/AlGaInP triple quantum-well laser structures was firstly reported in this work. N ions were implanted with the energy of 40 keV and dose of 1e17 ions/cm2, and thereafter rapid thermal annealing process were performed at 750 °C from 40 s to 200 s to induce the intermixing. The photoluminescence wavelength blue-shifts were found increased with the increasing time and the largest blue-shift of 54.9 nm was obtained for 200 s annealing. Surface morphology results shows that the photoluminescence improvement in the annealing samples came from the restoration effect of the layer crystal and hetero-structure interfaces. X-ray photoelectron spectroscopy tests shows that the implanting N ions tend to form Ga–N bonding besides generating point defect to induce quantum well intermixing.

Objectives Thalassemia is a highly prevalent monogenic inherited disease in southern China. It is important to collect epidemiological data comprehensively for proper prevention and treatment. Methods In this study, blood samples collected from 15 807 residents of Chenzhou were primarily screened by hematological tests. A total of 3973 samples of suspected thalassemia carriers were further characterized by combined next‐generation sequencing (NGS) and Gap‐PCR. Results In total, 1704 subjects were diagnosed as thalassemia carriers with a total prevalence rate of 10.78%, including 943 α‐thalassemia carriers, 708 β‐thalassemia carriers, and 53 composite α and β‐thalassemia carriers. The prevalence rates of α‐thalassemia, β‐thalassemia, and composite α and β‐thalassemia were 5.97%, 4.48%, and 0.34%, respectively. Meanwhile, we characterized 19 α‐thalassemia variations and 21 β‐thalassemia variations in thalassemia carriers. Approximately 2.88% of thalassemia carriers would be missed by traditional genetic analysis. In addition, four novel thalassemia mutations and one novel abnormal hemoglobin mutation were identified. Conclusions Our data suggest a high prevalence of thalassemia and a diverse spectrum of thalassemia‐associated variations in Chenzhou. Also, combined NGS and Gap‐PCR is an effective thalassemia screening method. Our findings might be helpful for prevention and treatment of thalassemia in this region.

Red-shift in 808 nm Al-free InGaAsP/GaInP active region using impurity free vacancy diffusion (IFVD) induced quantum well intermixing (QWI) was firstly reported in this paper. The laser diode wafer had an active region of single 12 nm InGaAsP quantum well and two 20 nm GaInP barriers and then 200 nm SiO 2 dielectric film was deposited on the surface of the wafer by magnetron sputtering. The QWI processes were induced by rapid thermal annealing (RTA) at different times and temperatures, respectively. Red-shift instead of blue-shift in the InGaAsP/GaInP active region was found increased with the increasing annealing time and annealing temperature, and the largest red-shift of 7.3 nm was obtained in the sample annealed at 750 °C for 210 s. The results were analyzed theoretically and experimentally by Ga distribution simulation and X-ray photoelectron spectroscopy (XPS) to testify the theory of QWI.

The effects of TMIn flow rate and AsH3 flow rate on the photoluminescence spectra of the high indium content InGaAs multiple quantum wells for lambda > 1.55 mu m laser diodes have been investigated both experimentally and theoretically. The wavelength peak red-shifted about 4.8 nm for increasing 1 sccm H-2 flow rate through TMIn under a AsH3 flow rate of 150 sccm, while the wavelength shift increases to 6.5 nm at a higher AsH3 flow rate of 300 sccm. Results show that more AsH3 flow rate will promote much TMGa pyrolysis than TMIn in the high indium content InGaAs growth. Considering the influence of growth parameters, the longest wavelength of 1.889 mu m among the InGaAs/InGaAsP strained MQWs samples was obtained with high crystal quality. (C) 2015 Elsevier B.V. All rights reserved.

Impurity free vacancy diffusion (IFVD) induced quantum well intermixing (QWI) based on electron beam evaporation hafnium dioxide (HfO2) in the red light diode laser wafer is firstly demonstrated in this work. The red light diode laser wafer had an active region of two 6 nm-thick GaInP quantum wells and three 8 nm-thick AlGaInP quantum barriers. 135 nm thick HfO2 film was evaporated on the surface of the diode laser wafer at 200 °C. The QWI processes were induced by rapid thermal annealing (RTA) for 20 s at different temperatures. The intensity and the full width at half maximum (FWHM) of the active region emitting wavelength were found increasing and decreasing with the increasing annealing temperature, respectively. When the sample was annealed at 1000 °C, a blue shift of 18 nm was found by the HfO2 IFVD induced QWI. Moreover, the diffusion lengths and inter-diffusion coefficients were calculated based on concentration distribution in the active region, and the inter-diffusion coefficient values were higher than the results in the Zn impurity diffusion induced QWI.

Quantum well intermixing (QWI) has been widely used in modifying the bandgap of semiconductor materials, post-growth; it has been investigated in fabricating non-absorbing mirror regions of laser cavities to improve output power. In this work, the QWI mechanism is briefly introduced. A concentration distribution function in multiple quantum wells is mathematically obtained for odd and even wells respectively. In addition, a 650 nm AlGaInP/GaInP quantum well wafer is fabricated by metal organic vapor phase epitaxy, and a series of quantum well intermixing experiments is accomplished by Zn impurity diffusions. Based on experimental data, a concentration distribution function is simulated and an inter-diffusion coefficient between Al and Ga is calculated. Finally, the effects of QWI on the inter-diffusion coefficient are discussed.

Phelan-McDermid syndrome is a neurodevelopmental disorder caused by the terminal deletion of chromosome 22 (22q13) followed by the loss of function of the SHANK3 gene. Various terminal deletions of chromosome 22q13 are associated with Phelan-McDermid with a spectrum of phenotypic severity. Here, we have done a clinical molecular study of a Chinese proband with Phelan-McDermid syndrome. Both the proband and her younger brother are associated with this syndrome while their parents are phenotypically normal. We used a karyotype in order to detect the genotype of the proband and her younger brother. We have also used whole genome low-coverage paired-end next generation sequencing to determine whether the parent is the carrier of translocation with terminal 22q13 deletions. We found that both proband and her younger brother are comprises of a novel deletion of 22q13.31q13.33, harboring genes were associated with several clinical phenotype such as severity of speech delay, neonatal hypotonia, delayed in age of walking, male genital anomalies, dysplastic toenails, large and fleshy hands, macrocephaly, short stature, facial asymmetry, and atypical reflexes. Probands and her younger brother inherited this translocation from their mother whereas their father is genotypically normal. In conclusion, our present study expands the deletion spectrum and report a novel deletion associated with Phelan-McDermid syndrome.

Acute lung injury is still a significant clinical problem having a high mortality rate despite significant advances in antimicrobial therapy and supportive care made in the past few years. Our previous study demonstrated that berberine (Ber) remarkably decreased mortality and attenuated the lung injury in mice challenged with LPS, but the mechanism behind this remains unclear. Here, we report that pretreatment with Ber significantly reduced pulmonary edema, neutrophil infiltration, and histopathological alterations; inhibited protein expression and phosphorylation of cytosolic phospholipase A2; and decreased thromboxane A2 release induced by LPS. Yohimbine, an alpha2-adrenergic receptor antagonist, did not antagonize these actions of Ber. Furthermore, pretreatment with Ber decreased TNF-alpha production and mortality in mice challenged with LPS, which were enhanced by yohimbine, and Ber combined with yohimbine also improved survival rate in mice subjected to cecal ligation and puncture. Taken together, these observations indicate that Ber attenuates LPS-induced lung injury by inhibiting TNF-alpha production and cytosolic phospholipase A2 expression and activation in an alpha2-adrenoceptor-independent manner. Berberine combined with yohimbine might provide an effective therapeutic approach to acute lung injury during sepsis.