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Abstract Background Weiss-Kruszka syndrome (WSKA) is a rare autosomal dominant syndrome characterized by multiple congenital anomalies caused by variants in the zinc finger protein 462 gene (ZNF462). About 40 cases of Weiss-Kruszka syndrome have been reported worldwide, and the aim of this study was to investigate the genetic causes of three patients from two Weiss-Kruszka syndrome family pedigrees with the aim of accumulating more data on the disease. Objective To explore the clinical and genetic characteristics of two pedigrees with Weiss–Kruszka syndrome. Methods The clinical data and family history of patients and family members of two pedigrees with Weiss–Kruszka syndrome were collected, and the pathogenic genes of the patients were analysed by whole-exon sequencing. Suspicious variants were verified by Sanger sequencing verification and bioinformatics prediction. Results Proband 1 has developmental delay, autistic behaviour, and abnormal electroencephalogram results. WES revealed a classical heterozygous c.6696–2 A > C splice variant of the ZNF462 gene, which was detected in neither parent. This position was conserved, and the variant was predicted to be deleterious. Minigene assays revealed that three types of aberrantly spliced mRNAs were produced. MRI of proband 2 suggested dysplasia of the corpus callosum with the formation of hemispheric cleft cysts, with a teardrop-like appearance in the lateral ventricle. WES revealed that a heterozygous c.4891 C > T:p. The Glu1631Ter nonsense variant of the ZNF462 gene was inherited from her mother. According to the guidelines of the American Society of Medical Genetics and combined with its clinical manifestations, c.6696–2 A > C and c.4891 C > T:p. Glu1631Ter was determined to be a possible pathogenic variant. Conclusion The c.6696-2 A>C and c.4891C > T:p.Glu1631Ter of the ZNF462 gene likely underlies Weiss–Kruszka syndrome in children (foetus), which enriches the variant spectrum of Chinese patients with Weiss–Kruszka syndrome and provides a basis for prenatal diagnosis and genetic counselling.

Abstract Background Mucopolysaccharidosis type I (MPS‐I) is a rare autosomal recessive genetic lysosomal storage disorder that is caused by pathogenic variants of the α‐L‐iduronidase (IDUA) gene. This study aimed to identify the genetic causes of MPS‐I in a Chinese patient and construct a minigene of IDUA to analyze its variants upon splicing. Methods Whole‐exome sequencing (WES) and Sanger sequencing were used to confirm the potential causative variants. Single‐nucleotide polymorphism (SNP) array was subsequently performed to confirm uniparental disomy (UPD). Minigene assay was performed to analyze the effect on splicing of mRNA. We meanwhile explored the conservative analysis and protein homology simulation. Results A novel homozygous splicing mutation of IDUA, c.159‐9T>A, was identified in an individual presenting with overlapping features of MPS‐I. Interestingly, only the father and sisters, but not the mother, carried the variant in a heterozygous state. WES and SNP array analyses validated paternal UPD on chromosome 4. Minigene splicing revealed two aberrant splicing events: exon 2 skipping and intron 1 retention. Moreover, the specific structure of the mutant protein obviously changed according to the results of the homologous model. Conclusions This study describes a rare autosomal recessive disorder with paternal UPD of chromosome 4 leading to the homozygosity of the IDUA splicing variant in patients with MPS‐I for the first time. This study expands the variant spectrum of IDUA and provides insights into the splicing system, facilitating its enhanced diagnosis and treatment.

BackgroundNeonatal screening for inherited metabolic diseases (IMDs) has been revolutionized by tandem mass spectrometry (MS/MS). This study aimed to enhance neonatal screening for IMDs using machine learning (ML) techniques.MethodsThe study involved the analysis of a comprehensive dataset comprising 309,102 neonatal screening records collected in the Ningbo region, China. An advanced ML system model, encompassing nine distinct algorithms, was employed for the purpose of predicting the presence of 31 different IMDs. The model was compared with traditional cutoff schemes to assess its diagnostic efficacy. Additionally, 180 suspected positive cases underwent further evaluation.ResultsThe ML system exhibited a significantly reduced positive rate, from 1.17% to 0.33%, compared to cutoff schemes in the initial screening, minimizing unnecessary recalls and associated stress. In suspected positive cases, the ML system identified 142 true positives with high sensitivity (93.42%) and improved specificity (78.57%) compared to the cutoff scheme. While false negatives emerged, particularly in heterozygous carriers, our study revealed the potential of the ML system to detect asymptomatic cases.ConclusionThis research provides valuable insights into the potential of ML in pediatric medicine for IMD diagnosis through neonatal screening, emphasizing the need for accurate carrier detection and further research in this domain.

In this paper, we demonstrate a domain inversion crystal structure to study the cascaded three-wave mixing process in a two peak Stark-chirped rapid adiabatic passage. We have achieved efficient wavelength conversion, which can be performed in intuitive order and counterintuitive order. The requirement of crystal is reduced and the flexibility of structure design is improved. When the conversion wavelength is fixed, increasing the coupling coefficient between the two peaks can reduce the intensity of the intermediate wavelength while maintaining high conversion efficiency. Compared with the cascaded wavelength conversion process based on stimulated Raman rapid adiabatic passage, the two-peak modulated Stark-chirped rapid adiabatic passage has a larger convertible wavelength bandwidth. This scheme provides a theoretical basis for obtaining mid-infrared laser source via flexible crystal structure.

In this paper, an efficient cascaded sum frequency generation (SFG) model based on Stark-chirped rapid adiabatic passage is established, in which the laser of signal, intermediate, and output corresponds to three primary, and an approach of white laser source synthesis is proposed. The research results show that the energy of the red laser can be almost converted into blue laser, while the green laser intensity is extremely low in the cascade SFG process. The farther away from the optimal coupling delay parameters, the smaller the corresponding conversion efficiency is. Meanwhile, the pump intensity has a larger control range for conversion efficiency. On the basis of these findings, a white laser source with a color temperature of 6500 K can be synthesized. We first roughly adjust the pump intensity to reduce the conversion efficiency so that the red, green and blue lasers coexist at the output. Then, we fine-tune the coupling delay parameters so that the output power ratio meets 0.61:0.28:0.11. These research results can provide a theoretical basis for achieving efficient frequency conversion and the development of new optical devices.

We propose a novel configuration for nonvolatile and reconfigurable tuning of surface lattice resonances (SLRs) based on thin films of phase-change material Ge2Sb2Te5 (GST). The configuration is composed of gold nanorod array embedded in a thin GST film. Results show that, an extremely wide SLR wavelength tuning range reaching 1600 nm, large tuning figure of merit of 21, and high SLR quality factors of 47 and 17 can be achieved in the mid-infrared regime when GST transits from the amorphous state into the crystalline state. The effects of the GST layer thicknesses on the SLR tuning performance are discussed, and the performances of several modified configurations are compared. We expect this work will advance the engineering of SLR tuning based on phase-change materials and promote its applications especially in nanolasing and narrowband filtering.

We investigate the influence of nonlinear crystal’s coupling modulation on wavelength conversion based on Stark-chirped rapid adiabatic passage. The result shows that the distribution of the efficient conversion is zonal with the change of coupling delay parameter. In addition, the efficient wavelength conversion can be performed in counterintuitive and intuitive order, which can reduce the restriction on the condition of conversion process compared to the stimulated Raman adiabatic passage. When the width parameter d12 is fixed, the larger the width parameter d22 is, the higher the maximum conversion efficiency is and the larger the bandwidth for efficient wavelength conversion is. These findings provide a theoretical basis for the efficient acquisition of laser sources from the visible to the mid-infrared and to the ultraviolet.

We propose a nonvolatile, reconfigurable, and narrowband mid-infrared bandpass filter based on surface lattice resonance in phase-change material Ge2Sb2Te5. The proposed filter is composed of a two-dimensional gold nanorod array embedded in a thick Ge2Sb2Te5 film. Results show that when Ge2Sb2Te5 transits from the amorphous state to the crystalline state, the narrowband reflection spectrum of the proposed filter is tuned from 3.197 μm to 4.795 μm, covering the majority of the mid-infrared regime, the peak reflectance decreases from 72.6% to 25.8%, and the corresponding quality factor decreases from 19.6 to 10.3. We show that the spectral tuning range can be adjusted by varying the incidence angle or the lattice period. By properly designing the gold nanorod sizes, we also show that the quality factor can be greatly increased to 70 at the cost of relatively smaller peak reflection efficiencies, and that the peak reflection efficiency can be further increased to 80% at the cost of relatively smaller quality factors. We expect that this work will advance the engineering of Ge2Sb2Te5-based nonvalatile tunable surface lattice resonances and will promote their applications especially in reconfigurable narrowband filters.

Hemodynamic response to motor execution (ME) and motor imagery (MI) was investigated using functional near-infrared spectroscopy (fNIRS). We used a 31 channel fNIRS system which allows non-invasive monitoring of cerebral oxygenation changes induced by cortical activation. Sixteen healthy subjects (mean-age 24.5 yeas) were recruited and the changes in concentration of hemoglobin were examined during right and left hand finger tapping tasks and kinesthetic MI. To suppress the systemic physiological interference, we developed a preprocessing procedure which prevents over-activated reporting in NIRS-SPM. In the condition of ME, more activation was observed in the anterior part of the motor cortex including the pre-motor and supplementary motor area (pre-motor and SMA), primary motor cortex (M1) and somatosensory motor cortex (SMC; t(15) > 2.27), however, in the condition of MI, more activation was found in the posterior part of motor cortex including SMC (t(15) > 1.81), which is in line with previous observations with functional magnetic resonance imaging (fMRI).

The high-efficiency three-process frequency conversion is analyzed. By analysis of coupling equations, the optical straddling stimulated Raman adiabatic passage (S-STIRAP) scheme is proposed. Numerical simulation shows that the input power of the first frequency is monotonically converted into the output power of the last frequency, with the intermediate frequencies kept extremely low along the interacting length. We expect that this frequency conversion scheme has application in the frequency conversion between highly disparate frequencies, e.g., mid-IR to visible.

A series of N-nitro acid amide derivatives compounds were synthesized based on the active site of target acetohydroxyacid synthase (AHAS, EC: 2.2.1.6) enzyme. All the structures of newly prepared compounds were thoroughly characterized by satisfied IR and 1H NMR spectra. The IC50 values against AHAS enzyme and EC50 values for herbicidal activity against Amaranthus mangostanus L. and Sorghum sudanense of all synthesized target compounds were determined. The compounds II-10, II-21, and II-22 with IC50 values of 7.09 mg/L, 9.07 mg/L, and 9.11 mg/L and the compounds II-8 and II-22 with EC50 values of 9.87 mg/L and 19.88 mg/L against root of Amaranthus mangostanus L. and Sorghum sudanense were illustrated, respectively. Meanwhile, the possible reasons for the lower activity of compounds were analyzed by molecular docking prediction.

A series of novel cycloalkylthieno[2,3-d]pyrimidinone derivatives have been conveniently synthesized via three steps including G-3CR, heterocyclization, and alkylation reactions as a part of our ongoing search for new bioactive molecules. The newly synthesized compounds were evaluated for their potential tumor cell growth inhibitory activity by standard MTT assay. The preliminary results show that compound 6b exhibited better inhibitory activities against HepG2, MCF-7, and BCG-823 cell lines compared to the control.

Photoacoustic (PA) signals carry much information related to the physical parameters of a sample, such as its optical, thermal, acoustic, and elastic properties. These physical parameters synchronously make their own contributions to PA signals. It is difficult to distinguish the contributions of different physical parameters to the mixed PA signals. To separate these parameters and to extract the featured information, we report herein a means of dissecting the transient PA signal using time-frequency analysis in a forward detection model. The simulated and experimental results indicate that the features of different physical parameters related to the sample can be qualitatively extracted from the mixed PA signals. [ABSTRACT FROM AUTHOR]

A series of essential oils oriented ester derivatives have been designed, synthesized and characterized based on the skeleton of fenvalerate. The preliminary bioassay results indicated that some of the newly synthesized compounds showed better insecticidal activities against Pyrausta nubilalis and Heliothis armigera than that of the control trans-prallethrin chloride. [ABSTRACT FROM AUTHOR]

We have recently applied the technique of drop coating deposition Raman (DCDR) spectroscopy for colorectal cancer (CRC) detection using blood plasma. The aim of this study was to develop a more convenient and stable method based on blood plasma for noninvasive CRC detection. Significant differences are observed in DCDR spectra between healthy (n = 105) and cancer (n = 75) plasma from 15 CRC patients and 21 volunteers, particularly in the spectra that are related to proteins, nucleic acids, and β-carotene. The multivariate analysis principal components analysis and the linear discriminate analysis, together with leave-one-out, cross validation were used on DCDR spectra and yielded a sensitivity of 100% (75/75) and specificity of 98.1% (103/105) for detection of CRC. This study demonstrates that DCDR spectroscopy of blood plasma associated with multivariate statistical algorithms has the potential for the noninvasive detection of CRC. [ABSTRACT FROM AUTHOR]

The feasibility of early detection of gastric cancer using near-infrared (NIR) Raman spectroscopy (RS) by distinguishing premalignant lesions (adenomatous polyp, n = 27) and cancer tissues (adenocarcinoma, n = 33) from normal gastric tissues (n = 45) is evaluated. Significant differences in Raman spectra are observed among the normal, adenomatous polyp, and adenocarcinoma gastric tissues at 936, 1003, 1032, 1174, 1208, 1323, 1335, 1450, and 1655 cm-1. Diverse statistical methods are employed to develop effective diagnostic algorithms for classifying the Raman spectra of different types of ex vivo gastric tissues, including principal component analysis (PCA), linear discriminant analysis (LDA), and naive Bayesian classifier (NBC) techniques. Compared with PCA-LDA algorithms, PCA-NBC techniques together with leave-one-out, cross-validation method provide better discriminative results of normal, adenomatous polyp, and adenocarcinoma gastric tissues, resulting in superior sensitivities of 96.3%, 96.9%, and 96.9%, and specificities of 93%, 100%, and 95.2%, respectively. Therefore, NIR RS associated with multivariate statistical algorithms has the potential for early diagnosis of gastric premalignant lesions and cancer tissues in molecular level. [ABSTRACT FROM AUTHOR]

In this paper, a two-phonon-resonance terahertz quantum cascade laser (THz QCL) based on GaN/AlGaN material system is proposed. GaN/AlGaN material system is first studied in two-phonon-resonance active region structure by using rate equations. The active region adds an energy state above the upper laser state. The energy state difference between additional state and the upper laser state is equal to the longitudinal optical phonon energy which has a large magnitude (∼90 meV). The simulation results show that the proposed THz QCL can get better optical properties compared with the traditional three-level active region building in the same material system and has the superiority in improving electronic utilization. The results also show that two-phonon-resonance THz QCL based on GaN/AlGaN material system can gain the peak output power of 8 mW at the temperature of 230 K. [ABSTRACT FROM AUTHOR]

The Raman spectra of tissue of 20 brain tumor patients was recorded using a confocal microlaser Raman spectroscope with 785 nm excitation in vitro. A total of 133 spectra were investigated. Spectra peaks from normal white matter tissue and tumor tissue were analyzed. Algorithms, such as principal component analysis, linear discriminant analysis, and the support vector machine, are commonly used to analyze spectral data. However, in this study, we employed the learning vector quantization (LVQ) neural network, which is typically used for pattern recognition. By applying the proposed method, a normal diagnosis accuracy of 85.7% and a glioma diagnosis accuracy of 89.5% were achieved. The LVQ neural network is a recent approach to excavating Raman spectra information. Moreover, it is fast and convenient, does not require the spectra peak counterpart, and achieves a relatively high accuracy. It can be used in brain tumor prognostics and in helping to optimize the cutting margins of gliomas. [ABSTRACT FROM AUTHOR]

We discuss theoretically a robustness of the difference frequency conversion method and demonstrate it by numerical simulation. This technique, borrowed from an analogous scheme of robust population transfer in atomic physics and nuclear magnetic resonance called ‘local optimization’, can keep the intermediate frequency fixed and make the counterintuitive ordering emerge automatically. Here we show an efficient frequency conversion in two-process three wave mixing (TWM). And because the local optimization method is a well-defined, automated computational procedure, we think it would be very useful in the efficient conversion of complicated multi-process TWM, which is a difficult subject in STIRAP. [ABSTRACT FROM AUTHOR]

A theoretical model is established for dealing with second-harmonic generation (SHG) in type I collagen excited by linearly polarized light focused by a microscope. With this model, the effects of the polarization angle , numerical aperture (NA), as well as the ratio of hyperpolarizability =xxxxyyon SHG emission have been investigated. Simulation results reveal that SHG emission power changes periodically as . The use of lower NA leads to weaker SHG emission but is more concentrated in two closer lobes, whereas more distributed emission in two detached lobes appear at higher NA. As the introduction of polarization direction, which is not along with the fiber axis (≠0 deg), one more element xyyis valid in our case than xxxalone, while their ratio plays a very important role for collagen features characterization. SHG emission with shows complicated modality that SHG emission is different at different and not symmetric at ±except at =0 deg, suggesting the important impact of polarization working on for SHG emission. Our theoretical simulation results provide useful clues for experimental study of microscopic SHG emission in collagen excited by linearly polarized beam. [ABSTRACT FROM AUTHOR]

The nanostructure Ce0.75Zr0.25O2 powders have been successfully synthesized by using the mechanically activated solid-state chemical reaction method for the first time, with Ce2(CO)3, ZrOCl2·8H2O, and H2C2O4·2H2O as raw materials. The structure andmorphology of Ce0.75Zr0.25O2 powders were characterized to be in the single cubic phase and spherical shape via X-ray powder diffraction, transmission electron microscopy, X-ray Photoelectron Spectrometer, and BET surface area testing technique. The average size of particles wasmeasured to be less than 20 nm, and the specific surface area was 85.4m²/g. The TG-DTA investigation was used to reveal the possibly chemical reaction mechanism during the synthesis process. The activity of Ce0.75Zr0.25O2 oxide solution in three-way catalysts was also valued in this work. [ABSTRACT FROM AUTHOR]