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1.
Opt Lett ; 49(11): 3046-3049, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824324

RESUMO

Solid-state indirect time-of-flight (iToF) cameras are crucial to numerous short-to-medium-range applications, owing to their advantages in terms of system integrability and long-term reliability. However, due to the low light intensity, the sensing range of iToF cameras is generally limited to a few meters, which hinders their wide applications. Further increasing the sensing range requires not only higher-power laser diodes but also well-designed driver circuits, which are based on prior knowledge of the laser diodes' equivalent circuits (ECs). However, experimental studies on ECs of a mounted, high-power vertical-cavity surface-emitting laser (VCSEL) array that comprehensively incorporates all parasitic components, especially parasitic stemming from printed circuit boards (PCBs), remain absent. In this Letter, an 850 nm VCSEL array with a 15.3 W peak power and a 581 MHz bandwidth is fabricated, and more importantly, its EC is experimentally established. Leveraging the accurate EC, a compact iToF camera with a sensing range up to 11.50 m is designed. In addition, a modified precision model is proposed to better evaluate the iToF camera's performance.

2.
Sensors (Basel) ; 24(5)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38475153

RESUMO

LiDAR has high accuracy and resolution and is widely used in various fields. In particular, phase-modulated continuous-wave (PhMCW) LiDAR has merits such as low power, high precision, and no need for laser frequency modulation. However, with decreasing signal-to-noise ratio (SNR), the noise on the signal waveform becomes so severe that the current methods to extract the time-of-flight are no longer feasible. In this paper, a novel method that uses deep neural networks to measure the pulse width is proposed. The effects of distance resolution and SNR on the performance are explored. Recognition accuracy reaches 81.4% at a 0.1 m distance resolution and the SNR is as low as 2. We simulate a scene that contains a vehicle, a tree, a house, and a background located up to 6 m away. The reconstructed point cloud has good fidelity, the object contours are clear, and the features are restored. More precisely, the three distances are 4.73 cm, 6.00 cm, and 7.19 cm, respectively, showing that the performance of the proposed method is excellent. To the best of our knowledge, this is the first work that employs a neural network to directly process LiDAR signals and to extract their time-of-flight.

3.
J Am Chem Soc ; 145(40): 21723-21728, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37769032

RESUMO

Perchlorate anions used in industry are harmful pollutants in groundwater. Therefore, selectively binding perchlorate provides solutions for environmental remediation. Here, we synthesized a series of tripodal organic cages with highly preorganized Csp3-H bonds that exhibit selectively binding to perchlorate in organic solvents and water. These cages demonstrated binding affinities to perchlorate of 105-106 M-1 at room temperature, along with high selectivity over competing anions, such as iodide and nitrate. Through single crystal structure analysis and density functional theory calculations, we identified unconventional Csp3-H···O interactions as the primary driving force for perchlorate binding. Additionally, we successfully incorporated this cage into a 3D-printable polymer network, showcasing its efficacy in removing perchlorate from water.

4.
Small ; 19(50): e2300323, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37029456

RESUMO

Plants produce a wide range of bioactive phytochemicals, such as antioxidants and vitamins, which play crucial roles in aging prevention, inflammation reduction, and reducing the risk of cancer. Selectively harvesting these phytochemicals, such as lycopene, from tomatoes through the adsorption method is cost-effective and energy efficient. In this work, a templated synthesis of 3D-printed crosslinked cyclodextrin polymers featuring nanotubular structures for highly selective lycopene harvesting is reported. Polypseudorotaxanes formed by triethoxysilane-based telechelic polyethylene glycols and α-cyclodextrins (α-CDs) are designed as the template to (1) synthetically access urethane-based nanotubular structures at the molecular level, and (2) construct 3D-printed architectures with designed macroscale voids. The polypseudorotaxane hydrogels showed good rheological properties for direct ink writing, and the 3D-printed hydrogels were converted to the desired α-CD polymer network through a three-step postprinting transformation. The obtained urethane-crosslinked α-CD monoliths possess nanotubular structures and 3D-printed voids. They selectively adsorb lycopene from raw tomato juice, protecting lycopene from photo- or thermo-degradations. This work highlights the hierarchically templated synthesis approach in developing functional 3D-printing materials by connecting the bottom-up molecular assembly and synthesis with the top-down 3D architecture control and fabrication.


Assuntos
Ciclodextrinas , Licopeno , Ciclodextrinas/química , Hidrogéis/química , Impressão Tridimensional , Uretana
5.
Opt Express ; 30(4): 5008-5018, 2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35209472

RESUMO

Silicon based optoelectronic integrated optical phased array is attractive owing to large-dense integration, large scanning range and CMOS compatibility. In this paper, we design and fabricate a SiN-on-SOI two-dimensional optical phased array chip. We demonstrate a two-dimensional scanning range of 96°×14.4° and 690 mW peak power of the main lobe. Additionally, we set up the time of flight (ToF) and frequency-modulated continuous-wave (FMCW) ranging systems by using this optical phased array chip, and achieve the objects detection at the range of 20 m in the ToF system and 109 m in the FMCW system, respectively.

6.
Angew Chem Int Ed Engl ; 61(52): e202214189, 2022 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-36331335

RESUMO

Iodine is widely used as an antimicrobial reagent for water disinfection in the wilderness and outer space, but residual iodine and iodide need to be removed for health reasons. Currently, it is challenging to remove low concentrations of iodine and iodide in water (≈5 ppm). Furthermore, the remediation of iodine and iodide across a broad temperature range (up to 90 °C) has not previously been investigated. In this work, we report a nitrate dimer-directed synthesis of a single-crystalline ionic hydrogen-bonded crosslinked organic framework (HC OF-7). HC OF-7 removes iodine and iodide species in water efficiently through halogen bonding and anion exchange, reducing the total iodine concentration to 0.22 ppm at room temperature. Packed HC OF-7 columns were employed for iodine/iodide breakthrough experiments between 23 and 90 °C, and large breakthrough volumes were recorded (≥18.3 L g-1 ). The high iodine/iodide removal benchmarks recorded under practical conditions make HC OF-7 a promising adsorbent for water treatment.


Assuntos
Iodo , Poluentes Químicos da Água , Purificação da Água , Iodetos/química , Iodo/química , Compostos Orgânicos , Desinfecção , Poluentes Químicos da Água/química
7.
Angew Chem Int Ed Engl ; 60(43): 23176-23181, 2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34378288

RESUMO

The development of large pore single-crystalline covalently linked organic frameworks is critical in revealing the detailed structure-property relationship with substrates. One emergent approach is to photo-crosslink hydrogen-bonded molecular crystals. Introducing complementary hydrogen-bonded carboxylic acid building blocks is promising to construct large pore networks, but these molecules often form interpenetrated networks or non-porous solids. Herein, we introduced heteromeric carboxylic acid dimers to construct a non-interpenetrated molecular crystal. Crosslinking this crystal precursor with dithiols afforded a large pore single-crystalline hydrogen-bonded crosslinked organic framework HC OF-101. X-ray diffraction analysis revealed HC OF-101 as an interlayer connected hexagonal network, which possesses flexible linkages and large porous channels to host a hydrazone photoswitch. Multicycle Z/E-isomerization of the hydrazone took place reversibly within HC OF-101, showcasing the potential use of HC OF-101 for optical information storage.

8.
J Am Chem Soc ; 141(13): 5154-5158, 2019 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-30912659

RESUMO

Covalent organic frameworks (COFs) are crystalline polymers with permanent porosity. They are usually synthesized as micrometer-sized powders or two-dimensional thin films and membranes for applications in molecular storage, separation, and catalysis. In this work, we report a general method to integrate COFs with imine or ß-ketoenamine linkages into three-dimensional (3D)-printing materials. A 3D-printing template, Pluronic F127, was introduced to coassemble with imine polymers in an aqueous environment. By limitation of the degree of imine polycondensation during COF formation, the amorphous imine polymer and F127 form coassembled 3D-printable hydrogels with suitable shear thinning and rapid self-healing properties. After the removal of F127 followed by an amorphous-to-crystalline transformation, three ß-ketoenamine- and imine-based COFs were fabricated into 3D monoliths possessing high crystallinity, hierarchical pores with high surface areas, good structural integrity, and robust mechanical stability. Moreover, when multiple COF precursor inks were employed for 3D printing, heterogeneous dual-component COF monoliths were fabricated with high spatial precision. This method not only enables the development of COFs with sophisticated 3D macrostructure but also facilitates the heterogeneous integration of COFs into devices with interconnected interfaces at the molecular level.

9.
Animals (Basel) ; 14(11)2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38891664

RESUMO

In recent years, genome-wide association studies (GWAS) have uncovered that the HOXB13 gene is a key regulatory factor for the tail length trait of sheep. Further research has found that there is a functional 168 bp SINE element insertion upstream of the HOXB13 gene, which leads to the occurrence of long tails in sheep. However, the frequency of mutations in the 168 bp SINE element of the HOXB13 gene among different sheep breeds around the world and its relationship with growth traits are still unclear. This study used whole-genome sequencing (WGS) data, including 588 samples from 33 different sheep breeds around the world, to evaluate the frequency of HOXB13 gene mutations in different sheep breeds globally. At the same time, this study also selected 3392 sheep samples from six breeds. The genetic variation in the 168 bp InDel locus in the HOXB13 gene was determined through genotyping, and its association with the growth traits of Luxi black-headed sheep was analyzed. The research results indicate that the polymorphism of the 168 bp InDel locus is significantly correlated with the hip width of adult ewes in the Luxi black-headed sheep breed (p < 0.05) and that the hip width of adult ewes with the DD genotype is significantly larger than that of adult ewes with the ID genotype (p < 0.05). This study indicates that there is consistency between the research results on the sheep tail length trait and growth traits, which may contribute to the promotion of sheep breed improvement.

10.
Front Surg ; 10: 1100720, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36814860

RESUMO

Background: Recently, a locking plate (LP) combined with a suture button was applied for distal clavicle Neer type IIb fractures. However, to our knowledge, there is limited information on clinical outcomes surrounding locking plates combined with a suture button in the treatment of Neer type IIb distal clavicle fractures. The aim of this study was to compare the outcomes among three different fixation techniques for the treatment of Neer type IIb distal clavicle fractures. Methods: We performed a retrospective cohort study of 53 patients with Neer type IIb distal clavicle fractures who were treated with a hook plate (HP group, 16 patients), a locking plate alone (LP group, 18 patients), or a locking plate with a suture button (LPSB group, 19 patients) in our hospital between March 2014 and August 2019. The clinical and radiological outcomes were evaluated, including union time, postoperative complications, and function of the shoulder joint. Results: The follow-up period was at least 2 years for all patients. All patients in the LPSB group achieved bone healing at the final follow-up. No significant differences were observed, including age, sex, side, time to surgery, duration of surgery, and mean follow-up period among the three groups (p > 0.05). The union time was shorter in the LPSB group than in the other two groups (p < 0.05). Postoperative complications were lower in the LPSB group than in the other two groups (p < 0.05). The visual analog scale score and Constant-Murley score in the LPSB group were better than those in the other groups at 3 and 6 months postoperatively (p < 0.05). Conclusion: Compared with HP and LP alone, LPSB yields better clinical outcomes and lower complication rates in the treatment of Neer type IIb distal clavicle fractures.

11.
BMJ Nutr Prev Health ; 6(1): 21-27, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37559968

RESUMO

Objectives: Even though disinfectants are commonly used in clinical practice and daily life, there are few studies on their antibacterial ability and cytotoxicity, which are closely related to the safety and effectiveness of their use. To provide a basis for the use of disinfectants, the cytotoxicity and antibacterial activity of three most commonly used disinfectants, povidone-iodine, chlorhexidine acetate and polyhexamethylene biguanide (PHMB), were investigated. Design: A CCK-8 assay was used to measure the activities of human fibroblasts (HF) and keratinocytes (HaCat), the two most important cells in wound healing, following their exposure to disinfectants. The effects of different times and concentrations were included. The antibacterial activity of disinfectants against Staphylococcus aureus, Acinetobacter baumannii, Klebsiella pneumoniae was reflected by their minimum inhibitory concentration and minimum bactericidal concentration. Results: All three disinfectants showed strong cytotoxicity in direct contact with HF and HaCat cells. Cytotoxicity increased with increasing exposure time and concentration. S. aureus, A. baumannii and K. pneumoniae comprised 70%, 55% and 85% of the strains sensitive to povidone iodine; 50%, 45% and 80% of the strains sensitive to chlorhexidine acetate; and 60%, 45% and 80% of the strains sensitive to PHMB, respectively. Conclusions: All three disinfectants were cytotoxic; therefore, it is necessary to pay attention to the use time and concentration in the clinical setting. All three disinfectants were cytotoxic, with povidone-iodine being the most cytotoxic even at low concentrations. PHMB had better antibacterial efficacy against S. aureus and is suitable for the treatment of shallow wounds primarily. All three tested bacteria were significantly more sensitive to PHMB than to the other disinfectants.

12.
Front Genet ; 13: 1030837, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36482907

RESUMO

Background: The natural history of patients with low-grade glioma (LGG) varies widely, but most patients eventually deteriorate, leading to poor prognostic outcomes. We aim to develop biological models that can accurately predict the outcome of LGG prognosis. Methods: Prognostic genes for glutamine metabolism were searched by univariate Cox regression, and molecular typing was constructed. Functional enrichment analysis was done to evaluate potential prognostic-related pathways by analyzing differential genes in different subtypes. Enrichment scores of specific gene sets in different subtypes were measured by gene set enrichment analysis. Different immune infiltration levels among subtypes were calculated using algorithms such as CIBERSORT and ESTIMATE. Gene expression levels of prognostic-related gene signatures of glutamine metabolism phenotypes were used to construct a RiskScore model. Receiver operating characteristic curve, decision curve and calibration curve analyses were used to evaluate the reliability and validity of the risk model. The decision tree model was used to determine the best predictor variable ultimately. Results: We found that C1 had the worst prognosis and the highest level of immune infiltration, among which the highest macrophage infiltration can be found in the M2 stage. Moreover, most of the pathways associated with tumor development, such as MYC_TARGETS_V1 and EPITHELIAL_MESENCHYMAL_TRANSITION, were significantly enriched in C1. The wild-type IDH and MGMT hypermethylation were the most abundant in C1. A five-gene risk model related to glutamine metabolism phenotype was established with good performance in both training and validation datasets. The final decision tree demonstrated the RiskScore model as the most significant predictor of prognostic outcomes in individuals with LGG. Conclusion: The RiskScore model related to glutamine metabolism can be an exceedingly accurate predictor for LGG patients, providing valuable suggestions for personalized treatment.

13.
Ann Palliat Med ; 9(2): 493-496, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32233635

RESUMO

Recently high-frequency electric knife and abdominal binder are widely used in the abdominal operation in China. Nevertheless, with the high occurrence of the abdominal wound, we think that whether both these operations could be used or not. Here, we report the case of a 40-year-old female patient where negative pressure wound therapy (NPWT) was applied to her dehisced abdominal wound as well as fat liquefaction and large skin necrosis with pleasing results. The patient with high fever was referred to our department from her earlier hospital for 6 days after cesarean delivery. During the surgery, her earlier doctor used a high-frequency electric knife for convenient-using, and after the operation, the patient immediately used an abdominal binder for good shape. However, the abdominal surgical incision was opened at postoperative day 3, with fat liquefaction releasing large fatty acids along both abdominal sides with penetration under the abdominal binder. After admitted at postoperative day 6 with aggravating wound, surgery was considered because of no reduction in the size of the wound. A series of vacuum sealing drainage (VSD) or vacuum-assisted closure (VAC) as well as others, were operated. In the admitted 25th day, the wound was completely closed. NPWT is a practical and effective therapy for the treatment of numerous refractory and intractable wounds. Therefore, we suggest that the high-frequency electric knife and an abdominal binder should be avoided using an abdominal operation. This case is the first report of the use of NPWT over a dehisced abdominal wound with fat liquefaction and large skin necrosis on a postpartum patient in China.


Assuntos
Parede Abdominal/patologia , Parede Abdominal/cirurgia , Tratamento de Ferimentos com Pressão Negativa/métodos , Deiscência da Ferida Operatória/patologia , Deiscência da Ferida Operatória/terapia , Adulto , Cesárea/efeitos adversos , Feminino , Humanos , Necrose/cirurgia , Infecção da Ferida Cirúrgica/prevenção & controle , Resultado do Tratamento , Cicatrização
14.
Exp Ther Med ; 16(2): 1477-1482, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30116397

RESUMO

Glioblastoma multiforme (GBM) is a malignant tumor caused by complex pathological mechanisms, and is characterized by a high rate of cancer-related mortality and poor patient prognosis. Overgrowth of cancer cells, which results from the inhibition of cell apoptosis and/or the promotion of cell proliferation, leads to the progression of GBM. Therefore, studies into the regulatory mechanisms of cancer cell growth in GBM are required to identify potential therapeutic targets and improve treatment for GBM. In the present study, the role of insulin-like growth factor 1 (IGF1)/IGF1 receptor (IGF1R) signaling in the survival of GBM cells was evaluated. It was observed that IGF1 significantly inhibited the intrinsic and extrinsic pathways of apoptosis (P<0.05), and overexpression of IGF1R significantly promoted the survival of GBM cells (P<0.05). Moreover, both exogenous IGF1 and overexpression of IGF1R promoted the phosphorylation of protein kinase B (AKT), and inhibition of the phosphoinositide 3-kinase (PI3K)/AKT pathway significantly attenuated the inhibitory effects of IGF1/IGF1R on GBM apoptosis (P<0.05). Collectively, these findings indicate that IGF1/IGF1R promotes the survival of GBM cells through activation of the PI3K/AKT pathway. Therefore, inhibition of IGF1/IGF1R may be a viable therapeutic strategy to suppress the progression of GBM.

15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 27(10): 2123-6, 2007 Oct.
Artigo em Zh | MEDLINE | ID: mdl-18306811

RESUMO

A method for the determination of lead in Chinese medicinal materials by GFAAS with PdCl2 as a matrix modifier was established. By comparing PdCl2 with NH4H2PO4 in improving effect on the determination of Pb, the dosage of PdCl2, acidity of medium, interference of coexistent ion, recovery of the method, precision of the method, and the detection limit were checked. The programmed temperature of graphite furnace was optimized. The results show that the improving effect of PdCl2 on Pb determination is better than that of NH4H2PO4. The dosage of PdCl2 is 0.3 microg. The best medium should be 1.0% HCl. The three kinds of acids, 0.4% H2SO4, 1.0% HClO4 and 1.8% HCl, did not weaken the signal of lead. The recovery of the method is 90%-104% and the precision is < 5.0%. The characteristic mass is 8.5 pg. The detection limit is 0.066 mg x kg(-1). It is concluded that the method is simple, sensitive, accurate and credible, and can be used widely.


Assuntos
Medicamentos de Ervas Chinesas/análise , Chumbo/análise , Plantas Medicinais/química , Espectrofotometria Atômica/métodos , Contaminação de Medicamentos/prevenção & controle , Chumbo/química , Espectrofotometria Atômica/instrumentação
16.
Chem Commun (Camb) ; 51(98): 17439-42, 2015 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-26468513

RESUMO

This communication reports a novel metal-organic framework exhibiting an excellent performance in adsorbing small toxic cationic herbicides, i.e. methyl viologen and diquat, with large adsorption capacities and ultratrace residue levels. To the best of our knowledge, this is the first example of high-performance MOFs trapping toxic cationic herbicides.

18.
Se Pu ; 20(4): 381-2, 2002 Jul.
Artigo em Zh | MEDLINE | ID: mdl-12541932

RESUMO

A simple and fast gas chromatographic method was used for the simultaneous determination of fluoroacetamide and tetramine. The samples were extracted with acetone and the extracts were analyzed by gas chromatography. A megabore capillary column coated with FFAP and a nitrogen-phosphorous detector were used to obtain satisfactory selectivity and sensitivity. The detection limits and average recoveries were 5 ng and 69.1% for fluoroacetamide and 1 ng and 89.8% for tetramine.


Assuntos
Hidrocarbonetos Aromáticos com Pontes/análise , Cromatografia Gasosa/instrumentação , Fluoracetatos/análise , Rodenticidas/análise , Cromatografia Gasosa/métodos
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