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Lateral meningocele syndrome (LMS) is a rare genetic connective tissue disorder which is associated with meningocele-related neurologic dysfunction. Several patients with LMS have been reported. But, guidelines for screening and treatment of LMS have not been established.We review the current knowledge of LMS in the article. Then, we describe a boy for whom a genomic analysis which allowed us to make a diagnosis of LMS and to begin monitoring of his condition for possible neurological complications.It would be difficult to make a diagnosis of LMS on the basis of clinical manifestations alone. The natural history of dural ectasia in patients with LMS needs to be better defined to establish surgical indications. Based upon the current literature, ventriculoperitoneal shunting (V-Ps) has been recommended as the first-line surgical treatment option for patients with symptomatic thoracolumbar meningoceles.

The variation of and the interrelation between different energy markets significantly affect the competitiveness of various energy technologies, therefore complicate the decision-making problem for a complex energy system consisting of multiple competing technologies, especially in a long-term time frame. The interrelations between these markets have not been accounted for in the existing energy system modelling efforts, leading to a distortion of understanding of the market impact on the technological choices and operations in the real world. This study investigates the strategic and operational decision-making problem for such an energy system characterized by three competing technologies from crude oil, natural gas, and coal. A stochastic programming model is constructed by incorporating multiple volatile energy prices interrelated with each other. Oil price is modelled by the mean-reverting Ornstein–Uhlenbeck process and serves as the exogenous variable in the ARIMAX models for natural gas and downstream plastic prices. The K-means clustering method is employed to extract a handful of distinctive patterns from a large number of simulated price projections to enhance the computing efficiency without losing retaining critical information and insights from the price co-movement. The model results suggest that the high volatility of the energy market weakens the possibility of selecting the corresponding technology. The oil-based route, for example, gradually loses its market share to the coal approach, attributed to a higher volatile oil market. The proposed method is applicable to other problems of the same kind with high-dimensional stochastic variables. Supplementary Information The online version contains supplementary material available at 10.1007/s10479-021-04229-3.

Currarino syndrome (CS) is a rare congenital disorder characterized by anorectal malformation, sacral agenesis and presacral mass. We performed video-urodynamics (VUDS) assessment of patients with CS to characterize the lower urinary tract function, individualize management plans and to follow outcomes. We conducted a cross-sectional study on 11 patients diagnosed with CS at the spina bifida multidisciplinary clinic. Lower urinary tract function was assessed by VUDS from three months to 12 months after neurosurgery. All patients had sacral agenesis; nine patients had anorectal malformation (9/11, 81.8%) and five patients had a presacral mass (5/11, 45.5%). The average age at neurosurgery was 7.9 months (range, 2–19). One patient had bilateral vesicoureteral reflux (VUR) with increasing detrusor pressure at the end of filling. In two patients, the detrusor activity showed weakening during urination, while no other lower urinary tract abnormality was identified on urodynamic evaluation. Six patients underwent VUDS before and after surgery; of these, two patients showed improved bladder function after surgery, while the remaining four patients showed no change in urodynamics. The average duration of follow-up was 27.5 months (range, 9–51). Renal function was normal in all patients. We can conclude that patients with CS often exhibit associated neurological abnormalities. VUDS assessment may help detect lower urinary tract dysfunction at an early stage and facilitate timely urological intervention to avoid kidney damage.

An irradiance profile measurement approach and profiling system were developed to measure the solar irradiance profile of the Arctic sea ice using fiber optic spectrometry. The approach involved using a miniature spectrometer to sense light signals collected and transmitted from a fiber probe. The fiber probe was small, and could thus move freely in inclined bore holes drilled in sea ice with its optical entrance pointing upward. The input-output relationship of the system was analyzed and built. Influence factors that determined the system output were analyzed. A correctional system output approach was proposed to correct the influence of these factors, and to obtain the solar irradiance profile based on the measurements outputted by this system. The overall performance of the system was examined in two ice floes in the Arctic during the 9th Chinese National Arctic Research Expedition. The measured solar irradiance profiles were in good agreement with those obtained using other commercially available oceanographic radiometers. The derived apparent optical properties of sea ice were comparable to those of similar sea ice measured by other optical instruments.

The extremely low temperature, high humidity and limited power supply pose considerable challenges when using spectrometers within the Arctic sea ice. The feasibility of using a miniature low-power near-infrared spectrometer module to measure solar radiation in Arctic sea ice environments was investigated in this study. Temperature and integration time dependences of the spectrometer module were examined over the entire target operating range of −50°C to 30°C, well below the specified operating range of this spectrometer. Using these observations, a dark output prediction model was developed to represent dark output as a function of temperature and integration time. Temperature-induced biases in the saturation output and linear operating range of the spectrometer were also determined. Temperature and integration time dependences of the signal output were evaluated. Two signal output correction models were developed and compared, to convert the signal output at any temperature within the operating temperature range and integration time to that measured at the reference temperature and integration time. The overall performance of the spectrometer was evaluated by integrating it into a refined fiber optic spectrometry system and measuring solar irradiance distribution in the ice cover with thickness of 1.85 m in the Arctic during the 9th Chinese National Arctic Research Expedition. The general shape of the measured solar irradiance above the snow surface agreed well with that measured by other commercial oceanographic spectroradiometers. The measured optical properties of the sea ice were generally comparable to those of similar ice measured using other instruments. This approach provides a general framework for assessing the feasibility of using spectrometers for applications in cold environments.

To reduce the amount of data transmitted, while retaining essential information on the original signal after reconstruction, this study investigated three different compression and reconstruction methods for the solar irradiance signals at different levels of the Arctic sea ice. To achieve this, characteristics of solar irradiance at different depths of the Arctic sea ice were analyzed; the solar irradiance profile was measured using a fiber optic spectrometer system at several ice packs from 11 to 25 August 2018, during the ninth Chinese National Arctic Research Expedition. Based on these measurements, three potential methods—fast Fourier transform (FFT), discrete wavelet transform (DWT), and Prony’s method—were selected and applied for the compression and reconstruction of a group of 12 measurements from one profile. The results indicated that the FFT method was generally superior to the DWT method considering the corrected reconstruction rate Rc, under the same compression ratio C. The FFT method had the highest Rc for signals with higher roughness, whereas Prony’s method was more suitable for smoother signals. To ensure that Rc was at least 80% and C was as large as possible, the compression and reconstruction method proposed in this study included the FFT method (C = 6.4) for the signals rougher than 1.5 and Prony’s method employing the matrix pencil method (C = 8) for the smoother signals. The proposed method was successfully verified using an independent group of solar irradiance measurements from another profile in the Arctic sea ice.

Microplastic pollution in aquatic environment has raised concern and as a result a number of studies have recently been published to find solutions for its rapid increase. Different methods have been proposed for microplastic identification. Spectral imaging shows a lot of promise for polymer identification; however, the identification time needs to be improved. Hyperspectral imaging (HSI) combined with chemometric analysis can reduce the identification times. In this study, we provide a review of recent studies related to polymer identification using HSI with a focus on the adopted classification algorithm and its factors for the online implementation of HSI. Furthermore, we review the limit of detection by HSI and the effect of particle size on classification accuracy. Additionally, performance of this method for various types of samples is also discussed. We conclude that HSI is possible to be a fast alternative for online microplastic detection.

The use of natural gas hydrate as a strategic alternative energy has increasingly attracted the attention of researchers in related fields. To study the properties of natural gas hydrate, however, obtaining the cores under in-situ pressure is a prerequisite because the cores are under particular combinations of high-pressure and low-temperature storage conditions. This article mainly presents the mechanism of a gravity piston corer in acquiring the pressure core of natural gas hydrate (up to 30 m long). The sampling theoretical model is established, and the corer's motion equation is thereafter derived. Based on the theoretical model, the penetration process of the gravity piston corer into the submarine sediment is analyzed. The weight, inner diameter, outer diameter, and initial speed, which are factors affecting the sampling process, are comprehensively elaborated. Additionally, the sampling process is numerically simulated using ABAQUS finite element software. It is found that the soil and pipe are influenced back by their coupling action, thus affording theoretical and numerical bases for the design and installation of a seabed operation structure. In its verification deployment in the South China Sea, the corer was operated numerous times at different depths; it successfully extracted pressure cores of natural gas hydrate. The theory and sea trails employed in this study are anticipated to support further research on abyssal pressure core corers.

HighlightsThe RC-PLSR model for Haiwan scallop can be transferred to Xiayi scallop.The direct standardization method is suggested for model maintenance.The VSWS-PDS method can be further improved in precision.Abstract. A prediction model for evaluating the moisture content in dried Haiwan scallops was established using hyperspectral imaging (HSI) technology in a previously published study. The accuracy of such models is usually affected by differences in sample species, different environmental conditions such as temperature or humidity, and aging of instruments. In this study, the prediction ability of the RC-PLSR model is improved by correcting the spectra of the tested species of dried scallop (i.e., Xiayi) to solve the problem of model failure caused by sample differences. The results of model maintenance by direct standardization (DS) are compared with those of variety sensitive wavelength selection - piecewise direct standardization (VSWS-PDS). The results showed that after using VSWS-PDS to modify the spectral data of the dried scallop samples, the correlation coefficient of prediction (Rp) of the updated model increased from 0.0890 to 0.9190. However, the root mean square error of prediction (RMSEP) also increased, indicating a need for improved precision. The RC-PLSR model based on DS correction showed Rp of 0.790 and RMSEP of 9.7481%. Model maintenance using the DS method is suggested because DS generally outperformed VSWS-PDS, even with a lower correlation coefficient. Future work on error reduction and sample input is suggested for VSWS-PDS optimization. Keywords: Direct standardization, Hyperspectral images, Model maintenance, Scallop, VSWS-PDS.

Arctic Ocean properties and processes are highly relevant to the regional and global coupled climate system, yet still scarcely observed, especially in winter. Team OCEAN conducted a full year of physical oceanography observations as part of the Multidisciplinary drifting Observatory for the Study of the Arctic Climate (MOSAiC), a drift with the Arctic sea ice from October 2019 to September 2020. An international team designed and implemented the program to characterize the Arctic Ocean system in unprecedented detail, from the seafloor to the air-sea ice-ocean interface, from sub-mesoscales to pan-Arctic. The oceanographic measurements were coordinated with the other teams to explore the ocean physics and linkages to the climate and ecosystem. This paper introduces the major components of the physical oceanography program and complements the other team overviews of the MOSAiC observational program. Team OCEAN’s sampling strategy was designed around hydrographic ship-, ice- and autonomous platform-based measurements to improve the understanding of regional circulation and mixing processes. Measurements were carried out both routinely, with a regular schedule, and in response to storms or opening leads. Here we present along-drift time series of hydrographic properties, allowing insights into the seasonal and regional evolution of the water column from winter in the Laptev Sea to early summer in Fram Strait: freshening of the surface, deepening of the mixed layer, increase in temperature and salinity of the Atlantic Water. We also highlight the presence of Canada Basin deep water intrusions and a surface meltwater layer in leads. MOSAiC most likely was the most comprehensive program ever conducted over the ice-covered Arctic Ocean. While data analysis and interpretation are ongoing, the acquired datasets will support a wide range of physical oceanography and multi-disciplinary research. They will provide a significant foundation for assessing and advancing modeling capabilities in the Arctic Ocean.

Sea ice growth and decay are critical processes in the Arctic climate system, but comprehensive observations are very sparse. We analyzed data from 23 sea ice mass balance buoys (IMBs) deployed during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition in 2019–2020 to investigate the seasonality and timing of sea ice thermodynamic mass balance in the Arctic Transpolar Drift. The data reveal four stages of the ice season: (I) onset of ice basal freezing, mid-October to November; (II) rapid ice growth, December–March; (III) slow ice growth, April–May; and (IV) melting, June onward. Ice basal growth ranged from 0.64 to 1.38 m at a rate of 0.004–0.006 m d–1, depending mainly on initial ice thickness. Compared to a buoy deployed close to the MOSAiC setup site in September 2012, total ice growth was about twice as high, due to the relatively thin initial ice thickness at the MOSAiC sites. Ice growth from the top, caused by surface flooding and subsequent snow-ice formation, was observed at two sites and likely linked to dynamic processes. Snow reached a maximum depth of 0.25 ± 0.08 m by May 2, 2020, and had melted completely by June 25, 2020. The relatively early onset of ice basal melt on June 7 (±10 d), 2019, can be partly attributed to the unusually rapid advection of the MOSAiC floes towards Fram Strait. The oceanic heat flux, calculated based on the heat balance at the ice bottom, was 2.8 ± 1.1 W m–2 in December–April, and increased gradually from May onward, reaching 10.0 ± 2.6 W m–2 by mid-June 2020. Subsequently, under-ice melt ponds formed at most sites in connection with increasing ice permeability. Our analysis provides crucial information on the Arctic sea ice mass balance for future studies related to MOSAiC and beyond.

Wang H, Li X, Wu C, Wu Z, Li Y, Yang T, Chen G, Xie X, Huang Y, Du Z, Zhou YX. Onco Targets Ther. 2015;8:3211–3218 The Editor and Publisher of OncoTargets and Therapy wish to retract the published article. Concerns were raised regarding alleged image duplication in Figure 2A and Figure 4. Specifically, Figure 2A, panel U87 Normal appears to show duplication with parts of Figure 2A, panel U87 Pre-miR-132 NC. Figure 2A, panel SHG44 Anti-miR-132 appears to show duplicated regions within the same image. Figure 2A, panel A172 Pre-miR-132 appears to show duplicated regions within the same image. Figure 2A, panel SHG44 Pre-miR-132 appears to show duplicated regions within the same image. Figure 2A, panels U87 Normal and Anti-miR-132 NC appear to show duplicated regions with Figure 4A, panel U87 Mock from Yang et al (2014) (https://doi.org/10.1111/cas.12351). Figure 2A, panel U87 Anti-miR-132 appears to show duplication with parts of Figure 4A, panel U87 Negative from Yang et al (2014) (https://doi.org/10.1111/cas.12351). The authors were contacted and did provide an explanation for the duplicated images, but it was not satisfactory. In addition, the authors did provide some original data but again it was not satisfactory, and the findings of the paper were deemed to be invalid. Our decision-making was informed by our policy on publishing ethics and integrity and the COPE guidelines on retraction. The retracted article will remain online to maintain the scholarly record, but it will be digitally watermarked on each page as “Retracted”. This retraction relates to this paper

The acquired Chiari type I malformation is a rare late complication of supratentorial shunting in children which is often accompanied by abnormal cranial vault thickening. Several surgical treatments for this disease have been proposed including supratentorial skull enlarging procedures and subtentorial craniotomy. But there is still debate about the best treatment strategy for this disease. We reviewed the current knowledge of this disease in the paper. We illustrated one patient of symptomatic acquired Chiari type I malformation who had cysto-peritoneal (C-P) shunting and ventriculoperitoneal (V-P) shunting. We observed the CSF flow dynamic of this patient at different periods. The acquired Chiari type I malformation disappeared on imaging after thinning the occipital planum combined with the standard surgical therapy of Chiari decompression. The symptoms of the patient were relieved after surgery. Overshunting manifestations require prompt recognition and management. Preventive measures should be taken which include making a stringent selection of cases being considered for surgery, avoiding C-P drainage, and placing of a programmable valve as initial treatment of intracranial arachnoid cysts (AC) if shunting is considered.

An irradiance profiling system was developed to obtain long-term autonomous measurements of solar irradiance above, within, and under sea ice in the Arctic. Two miniature spectrometers were adopted to sequentially sense light signals collected and transmitted by eight fiber probes deposited at different levels of the sea ice environment. Each spectrometer was aligned to each fiber probe by rotating the spectrometer to the desired angle by using a rotary spectrometer switching device. A small optical probe was developed that could be placed in an auger hole with a diameter of 5 cm and enable a high transmission rate for the light signal. The temperature dependence of the signal output was examined and evaluated over the entire operating temperature range from −50° to +30°C. A signal output correction model was proposed to correct temperature-induced biases in the system output; this was combined with the system spectral sensitivity correction to determine the absolute irradiance entering the system. The performance of the system was examined for two days during the ninth Chinese National Arctic Research Expedition by deploying it in a 185-cm-thick ice pack in the Arctic and measuring the solar irradiance distribution at different levels. The spectral shape of the measured solar irradiance above the sea ice agreed well with that measured using other commercial oceanographic spectroradiometers. The measured optical properties of the sea ice were generally comparable to those of similar ice measured using other instruments.

ᅟJaffe-Campanacci is a rare syndrome characterised by axillary freckles, multiple non-ossifying fibromas of the long bones and jaw, and cafe-au-lait spots, associated with some features of neurofibromatosis type 1 (NF1). Cherix et al. and Colby and Saul suggested that Jaffe-Campanacci syndrome (JCS) might be a distinct form of NF1. Intracranial arterial dolichoectasia (IADE) is defined as an increase in the length and diameter of at least one intracranial artery. Affected intracranial arteries are dilated, elongated and sometimes tortuous. But in this rare disease of JCS, neither skull damage nor IADE has been previously reported. Here, we introduce the case of an 11-year-old Chinese girl with IADE, skull damage and features of JCS.

Based on the structure-oriented lumping method, a molecular-level reaction kinetic model of the delayed coking process, which adopted 24 structural increments to construct the feed molecular matrix containing 2,944 molecules, was established with a reaction network containing 74,581 reactions using MATLAB. The reliability of the model was verified by experimental results. According to the discriminant rules of structural increments, 173 structural vectors in gasoline and 1,132 structural vectors in diesel were classified into different group compositions, respectively. The model could track the reaction path of any specific molecule in the complex thermal cracking reaction network. The influences of operation conditions such as recycle ratio on the product distribution could be discovered through the calculation of the molecular-level model, which is helpful for the process optimization and precise regulation of product composition for the delayed coking plants.

Chiari I malformation (CIM) is a common pediatric neurologic anomaly which could be associated with a variety of genetic disorders. However, it is not always clear whether the observed associations between CIM and RASopathies are real or random. The knowledge of the real association could provide useful guidance to clinicians. Furthermore, it could help to better understand the still unknown genetic etiology of CIM. We reviewed the current knowledge of CIM and RASopathies in the paper. Here, we describe one patient with CIM and Noonan syndrome and three patients with CIM and neurofibromatosis type 1. Three of the four patients underwent standard surgical therapy of Chiari decompression and had a straightforward recovery without further complications from surgery. In RASopathy, imaging of the nervous system may be necessary. With the increase in availability of magnetic resonance imaging, we believe that there will be a growing body of evidence to suggest that CIM is more commonly seen in RASopathy. Future studies should attempt to elucidate the pathogenic mechanism responsible for CIM mediated by the RAS/MAPK signaling pathway.

The aim of this study is to conduct a retrospective review of data obtained in all consecutive patients who had undergone cerebral decompression using the 3-pillar expansive craniotomy (3PEC) in our hospital between 2016 and 2020. We developed a novel craniotomy technique using expansion cranioplasty in patients with traumatic brain injury or stroke, which could relieve intracranial hypertension, maintain cerebral protection, and avoid subsequent cranial repair. Sixteen patients aged 2-18 years old underwent the 3PEC. Two patients, who presented very severe neurological conditions at the admission, died. All surviving patients showed good neurological outcome. None of the survived patients presented with bone flap resorption or sinking flap syndrome. The role of decompressive craniectomy has been recently questioned in the pediatric population by the use of decompressive craniotomy. In this limited study of children patients experiencing stroke or traumatic brain injury, 3PEC was proved useful in reducing intracranial pressure (ICP), thus, questioning the role of decompressive craniectomy in children. The technique effectively reduces postoperative complications and eliminates subsequent cranioplasty procedures otherwise introduced by traditional decompressive craniectomy.

Harmful algae blooms (HAB) in eutrophic lakes and rivers have become serious water quality problems that are difficult to eliminate using common methods. Previous research has demonstrated that powerful ultrasound can somewhat control cyanobacteria in HABs, however, effective and energy-efficient settings for ultrasonic parameters have not yet been rigorously determined. The results of this study showed that the effect of cyanobacteria removal was enhanced with ultrasonic frequencies, densities, and radiation durations of 20&ndash, 90 kHz, 0.0005&ndash, 0.1 W/mL and 0.5&ndash, 10 min, respectively. Our analyses further demonstrated that the effective distance of ultrasound decreased with increasing frequency, and that damaged algae cells were able to repair themselves at low ultrasonic densities. To address the high energy consumption and small effective distance of conventional ultrasonic radiation treatments, we proposed a new cyanobacteria removal method based on two applications of low-frequency, low-density and short-duration ultrasonic radiation. We defined the energy effectiveness factors of ultrasonic radiation for algae removal as the algae removal rate divided by ultrasonic dosage. This method yielded an 87.6% cyanobacteria removal and the highest energy effectiveness factor, suggesting that two cycles of treatment provide a low-energy method for enhancing existing algae-removing technologies used in large bodies of water.

Focusing performance is a major concern for systems based on hydrodynamic focusing. In this study, the hydrodynamic focusing subsystem of a microscopic imaging system was analysed and modelled. The theoretical model was used to analyse the velocity and distribution range of sample particles in the focused sample flow in the micro-channel of the hydrodynamic focusing subsystem, when the velocities of the sample and sheath flows were varied. The results were used to optimise the coupling velocities of the sample and sheath flows for the microscopic imaging system, to keep working efficiency and image quality of the system simultaneously. An independent experiment was then conducted for verification, and the results agreed well with the theoretical investigation. The results of this study provide a general framework for adjusting the sample and sheath flow velocities to optimise the hydrodynamic focusing performance.

Floating ocean seismograph (FOS) is a vertical underwater vehicle used to detect ocean earthquakes by observing P waves at teleseismic distances in the oceans. With the requirements of rising to the surface and transmitting data to the satellite in real time and diving to the desired depth and recording signals, the depth control of FOS needs to be zero overshoot and accurate with fast response. So far, it remains challenging to implement such depth control due to the variation of buoyancy caused by the seawater density varying with the depth. The deeper the water is, the greater the impacts on buoyancy are. To tackle it, a fuzzy sliding mode controller considering the influence of seawater density change is proposed and simulated in MATLAB/SIMULINK based on the variable buoyancy system and state space function of FOS. Compared with proportional-integral-derivative (PID) controller, fuzzy PID controller and sliding mode controller, the simulation results indicate that the proposed controller shows its superiority regardless of the disturbing force. Its advantages include smaller steady-state error, faster response time, smaller system chatter, and well robustness. This proves that the designed fuzzy sliding mode controller is able to meet the working requirements and thus, lays a foundation for FOS application.

Microplastic pollution in aquatic environment has raised concern and as a result a number of studies have recently been published to find solutions for its rapid increase. Different methods have been proposed for microplastic identification. Spectral imaging shows a lot of promise for polymer identification; however, the identification time needs to be improved. Hyperspectral imaging (HSI) combined with chemometric analysis can reduce the identification times. In this study, we provide a review of recent studies related to polymer identification using HSI with a focus on the adopted classification algorithm and its factors for the online implementation of HSI. Furthermore, we review the limit of detection by HSI and the effect of particle size on classification accuracy. Additionally, performance of this method for various types of samples is also discussed. We conclude that HSI is possible to be a fast alternative for online microplastic detection.

A new scoring function to learn the dependence structure from a process alarm dataset is proposed here. Based on the new function, a Bayesian network based method is developed to analyze alarm system performance. The proposed method is composed of four features: i) identifying essential variables from alarm data, ii) learning the structure of the Bayesian network from the alarm data; iii) learning the quantitative dependence of the variables in the Bayesian network, and iv) quantitatively describing the strength among the dependent variables. The proposed method helps to describe alarm variables relationships better, enable alarm diagnostic to identify the root causes, and study the variables dependence strength and finally improve the alarm system performance. The proposed method is first explained with a simple example, and further application is demonstrated with a case study of an industrial distributed control system-based alarm system.

The dual functional hydrogen peroxide (H2O2) assisted strategy for preparation of homogeneously distributed sulfur quantum dots (SQDs) with tunable size and prominent photoluminescence (PL) property is originally proposed via a one-pot solvothermal method. The synthesis of SQDs was demonstrated by treating sublimated sulfur powder and polyethylene glycol-400 (PEG-400) in the presence of H2O2 at elevated temperature. The H2O2 acts as a dual-functional reagent which could suspend the sulfur powder and etching bulk sulfur to construct uniform SQDs. At elevated temperature, the sulfur powder are easily transformed to molten sulfur which simultaneously acts as solvent. The as obtained SQDs exhibit a uniform size distribution, excellent PL properties with quantum yields (QYs) up to 10.3 %, superior dispersibility, and eminent photo stability. Moreover, morphology and element characterization reveal that the surface of spherical SQDs equipped with abundant oxidized sulphur species, while the diversification in the PL and QYs of SQDs under different reaction time are derived from the difference in their particle size which is proposed by the etching-assemble-etching process. Finally, the resultant SQDs was utilized as a sensitive iron ions (Fe3+) sensor with limit of detection (LOD) up to 10.80 nM as well as their investigation for fluorescent cellular imaging.

In order to describe the reaction network and investigate the conversion behavior of sulfur compounds in delayed coking process, a molecular-level reaction kinetic model was established with a reaction network consisting of 81,081 reactions based on the structure-oriented lumping method. A feed molecular matrix containing 2,944 structural vectors was constructed with 24 structural increments based on the characteristics of the vacuum residue molecular composition. The reliability of the model was verified by industrial data. Through the calculation of the SOL model, the sulfur compounds in gasoline were expressed as 57 structural vectors, which were divided into thiophenes, mercaptans and thioethers according to the discriminant rules. The conversion law of sulfur compounds was investigated by tracking the reaction path of molecules in the reaction network. The SOL model could calculate the distribution of sulfur compounds in coking gasoline. The contents of thiophene molecules increased with the carbon numbers. Ethyl mercaptan and propyl mercaptan had higher content in mercaptans. The SOL model can reveal the influences of reaction conditions on sulfur compounds conversion in delayed coking process at the molecular level, which contributes to the accurate control of sulfur content in coking gasoline.

A modeling method is proposed for a dynamic fast steering mirror (FSM) system with dual inputs and dual outputs. A physical model of the FSM system is derived based on first principles, describing the dynamics and coupling between the inputs and outputs of the FSM system. The physical model is then represented in a state-space form. Unknown parameters in the state-space model are identified by the subspace identification algorithm, based on the measured input-output data of the FSM system. The accuracy of the state-space model is evaluated by comparing the model estimates with measurements. The variance-accounted-for value of the state-space model is better than 97%, not only for the modeling data but also for the validation data set, indicating high accuracy of the model. Comparison is also made between the proposed dynamic model and the conventional static model, where improvement in model accuracy is clearly observed. The model identified by the proposed method can be used for optimal controller design for closed-loop FSM systems. The modeling method is also applicable to FSM systems with similar structures.

Herein, a hyperspectral imaging system in the 380–1030 nm range was used to rapidly determine the moisture content of scallops in different dehydration periods. Mean spectral values of scallops were extracted from hyperspectral images. Only eight optimal wavelengths were selected using the regression coefficient method. Spectra of full wavebands and selected wavelengths were used as independent variables for modeling. Partial least squares regression (PLSR) and least-squares support vector machines (LSSVM) were employed to establish multispectral calibration models to correlate spectral features with moisture content. The best results, with correlation coefficients of prediction (RP), root mean square error of prediction (RMSEP), and residual predictive deviation (RPD) of 0.9673, 3.5584%, and 3.7150, respectively, were achieved using the optimal wavelength-based PLSR model. To visualize moisture content in scallops, a visualization map was generated using the selected wavelength-based PLSR model. These results highlight the potential of hyperspectral imaging for non-destructive prediction of moisture content in scallops.

Estimation of unknown parameters in exponential models by linear and nonlinear fitting methods is discussed. Based on the extreme value theorem and Taylor series expansion, it is proved theoretically that the parameters estimated by the linear fitting method alone cannot minimize the sum of the squared residual errors in the measurement data when measurement noise is involved in the data. Numerical simulation is performed to compare the performance of the linear and nonlinear fitting methods. Simulation results show that the linear method can obtain only a suboptimal estimate of the unknown parameters and that the nonlinear method gives more accurate results. Application of the fitting methods is demonstrated where the water spectral attenuation coefficient is estimated from underwater images and imaging distances, which supports the improvement in the accuracy of parameter estimation by the nonlinear fitting method.

Tumor driver genes are genes where structural or sequence mutations confer a selective advantage for cancer cells. The individualized targeting of tumor driver genes has become a topic of interest for tumor treatment. The prognosis for medulloblastoma (MB), a common type of malignant intracranial tumor found in children, is poor. The tumor driver genes and the corresponding targeted drugs remain to be studied. The present study analyzed tumor driver genes from tumor tissue and peripheral blood from one patient with nodular desmoplastic MB with Sonic Hedgehog activation and screened targeted drugs for the tumor driver genes. Additionally, MB tissue was successfully implanted into the SCID mouse which were then used for subsequent drug screening. The present study explored novel treatments for MB from the perspective of tumor driver genes, and may provide new ideas for choosing individualized targeted therapies for patients with MB.

Ice algae plays an important role in the polar marine ecosystem, so it is essential to estimate the biomass of polar ice algae. In this paper, we measured the internal irradiance of sea ice and calculated the spectral attenuation characteristics of sea ice media. We used Empirical Orthogonal Function(EOF) analysis to reduce the dimension of data, extract the characteristics of spectral attenuation coefficient, and established the relationship between chlorophyll a concentration and spectral attenuation coefficient through Generalized Linear Model. A method for estimating the biomass of polar ice algae represented by chlorophyll a concentration was proposed.

Observing phytoplankton can help understand the carbon and nutrient fluxes in marine ecosystems and is an important indicator of how human activities affect coastal marine ecosystems. However, most of the phytoplankton have complex, irregular appearance, internal structure, organic or chemical composition and biological activity, which makes it difficult to detect. Recent years, the rapid development of automatic image systems based on high precision cameras has made it possible to study plankton on fine temporal and spatial scales. In this paper, We focus on the different sample paths and velocities, especially the micro particles of around 20μm, under the change of ratio of sample flow and sheath flow rate, and will theoretically analyze the hydrodynamic focusing process of micro particles in the square channel, and simulating the movement of the sample particles in sheath flow by computational fluid dynamics method to find an appropriate combination of the sheath flow and sample flow for hydro dynamically focusing.

A molecular level model for Fluid Catalytic Cracking (FCC) process was established based on the Structure-Oriented-Lumping (SOL) method to investigate the effects of the diameter expanding reactor on the product distribution. According to the molecular composition characteristics of feed oil, 24 structural increments were adopted to construct a molecular matrix containing 4539 molecules. Combined with the SOL reaction rules, a reaction network consisting of 118,272 reactions was established using MATLAB. The contents of 266 molecules in gasoline and 1189 molecules in diesel oil were calculated using the molecular level models of diameter expanding reactor and conventional reactor. The olefins content in gasoline, which is the summarization of 83 olefins molecules, increased as the reaction temperature went up. Compared with the conventional reactor, the ratio of isopentane to pentene in the diameter expanding reactor increased from 1.38 to 2.59 and the ratio of toluene to methylcyclohexane increased from 2.69 to 3.94. The model illustrated that the diameter expanding reactor could enhance the hydrogen transfer and isomerization reactions from the molecular level to reduce the olefins content and improve the iso-paraffins content in gasoline. The model could describe the molecular level product distribution from the reactor inlet to the outlet.