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1.
Forensic Sci Int ; 360: 112074, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38823217

ABSTRACT

Synthetic cathinones, which are novel psychoactive substances, have caused major social problems worldwide. A substance called 2-methyl-4'-(methylthio)-2-morpholinopropiophenone (MMMP), which is employed as a commercial industrial photoinitiator for triggering polymerization, has a basic cathinone backbone; however, few reports regarding MMMP have been published. In the current study, three potential metabolites of MMMP-namely hydroxy-MMMP (HO-MMMP), HO-MMMP-sulfoxide (HO-MMMP-SO), and HO-MMMP-sulfone (HO-MMMP-SO2)-were successfully synthesized, and MMMP and these three potential metabolites were used as standards to establish an analytic method based on liquid chromatography-tandem mass spectrometry for the quantitative analysis of urine. This analytic method and related parameters-including dynamic range, limit of quantification, selectivity, precision, accuracy, carryover effect, matrix effect, interference, and dilution integrity-were optimized and validated. Forty urine samples from 1,691 individuals who abused drugs were determined to contain MMMP, HO-MMMP, HO-MMMP-SO, or HO-MMMP-SO2; the results of this study indicate that approximately 2.37 % of drug abusers in Taiwan consumed MMMP in 2023. These 40 urine samples were analyzed to investigate the metabolism of MMMP in humans. The results indicate that HO-MMMP-SO is the main metabolite in human urine. This study recommends HO-MMMP-SO with a concentration of 2 ng/mL as a target and cutoff value, respectively, for identifying individuals who have consumed MMMP.


Subject(s)
Psychotropic Drugs , Tandem Mass Spectrometry , Humans , Psychotropic Drugs/urine , Psychotropic Drugs/analysis , Chromatography, Liquid , Propiophenones/urine , Substance Abuse Detection/methods , Illicit Drugs/analysis , Morpholines/urine , Morpholines/analysis , Limit of Detection
2.
J Phys Chem Lett ; 15(21): 5728-5737, 2024 May 30.
Article in English | MEDLINE | ID: mdl-38771736

ABSTRACT

Nitrogen-doped carbon dots (NCDs) featuring primary pyrrolic N and pyridinic N dominated configurations were prepared using hydrothermal (H-NCDs) and microwave (M-NCDs) methods, respectively. These H-NCDs and M-NCDs were subsequently applied to decorate CsPbBr3 nanocrystals (CPB NCs) individually, using a ligand-assisted reprecipitation process. Both CPB/M-NCDs and CPB/H-NCDs nanoheterostructures (NHSs) exhibited S-scheme charge transfer behavior, which enhanced their performance in photocatalytic CO2 reduction and selectivity of CO2-to-CH4 conversion, compared to pristine CPB NCs. The presence of pyrrolic N configuration at the heterojunction of CPB/H-NCDs facilitated efficient S-scheme charge transfer, leading to a remarkable 43-fold increase in photoactivity. In contrast, CPB/M-NCDs showed only a modest 3-fold enhancement in photoactivity, which was attributed to electron trapping by pyridinic N at the heterojunction. The study offers crucial insights into charge carrier dynamics within perovskite/carbon NHSs at the molecular level to advance the understanding of solar fuel generation.

3.
Polymers (Basel) ; 16(7)2024 Mar 22.
Article in English | MEDLINE | ID: mdl-38611132

ABSTRACT

In low-pressure wax injection molding, cooling time refers to the period during which the molten plastic inside the mold solidifies and cools down to a temperature where it can be safely ejected without deformation. However, cooling efficiency for the mass production of injection-molded wax patterns is crucial. This work aims to investigate the impact of varying surface roughness on the inner walls of the cooling channel on the cooling efficiency of an aluminum-filled epoxy resin rapid tool. It was found that the cooling time for the injection-molded products can be determined by the surface roughness according to the proposed prediction equation. Employing fiber laser processing on high-speed steel rods allows for the creation of microstructures with different surface roughness levels. Results demonstrate a clear link between the surface roughness of cooling channel walls and cooling time for molded wax patterns. Employing an aluminum-filled epoxy resin rapid tool with a surface roughness of 4.9 µm for low-pressure wax injection molding can save time, with a cooling efficiency improvement of approximately 34%. Utilizing an aluminum-filled epoxy resin rapid tool with a surface roughness of 4.9 µm on the inner walls of the cooling channel can save the cooling time by up to approximately 60%. These findings underscore the significant role of cooling channel surface roughness in optimizing injection molding processes for enhanced efficiency.

4.
Polymers (Basel) ; 16(7)2024 Apr 04.
Article in English | MEDLINE | ID: mdl-38611249

ABSTRACT

Polylactic acid (PLA) stands out as a biomaterial with immense potential, primarily owing to its innate biodegradability. Conventional methods for manufacturing PLA encompass injection molding or additive manufacturing (AM). Yet, the fabrication of sizable medical devices often necessitates fragmenting them into multiple components for printing, subsequently requiring reassembly to accommodate the constraints posed by the dimensions of the AM platform. Typically, laboratories resort to employing nuts and bolts for the assembly of printed components into expansive medical devices. Nonetheless, this conventional approach of jointing is susceptible to the inherent risk of bolts and nuts loosening or dislodging amid the reciprocating movements inherent to sizable medical apparatus. Hence, investigation into the joining techniques for integrating printed components into expansive medical devices has emerged as a critical focal point within the realm of research. The main objective is to enhance the joint strength of PLA polymer rods using rotary friction welding (RFW). The mean bending strength of welded components, fabricated under seven distinct rotational speeds, surpasses that of the underlying PLA substrate material. The average bending strength improvement rate of welding parts fabricated by RFW with three-stage transformation to 4000 rpm is about 41.94% compared with the average bending strength of PLA base material. The average surface hardness of the weld interface is about 1.25 to 3.80% higher than the average surface hardness of the PLA base material. The average surface hardness of the weld interface performed by RFW with variable rotational speed is higher than the average surface hardness of the weld interface performed at a fixed rotating friction speed. The temperature rise rate and maximum temperature recorded during RFW in the X-axis of the CNC turning machine at the outer edge of the welding part surpassed those observed in the internal temperature of the welding part. Remarkably, the proposed method in this study complies with the Sustainable Development Goals due to its high energy efficiency and low environmental pollution.

5.
Front Neurol ; 15: 1286856, 2024.
Article in English | MEDLINE | ID: mdl-38450075

ABSTRACT

Purpose: Evidence suggests that transcranial direct current stimulation (tDCS) can enhance motor performance and learning of hand tasks in persons with chronic stroke (PCS). However, the effects of tDCS on the locomotor tasks in PCS are unclear. This pilot study aimed to: (1) determine aggregate effects of anodal tDCS combined with step training on improvements of the neural and biomechanical attributes of stepping initiation in a small cohort of persons with chronic stroke (PCS) over a 4-week training program; and (2) assess the feasibility and efficacy of this novel approach for improving voluntary stepping initiation in PCS. Methods: A total of 10 PCS were randomly assigned to one of two training groups, consisting of either 12 sessions of VST paired with a-tDCS (n = 6) or sham tDCS (s-tDCS, n = 4) over 4 weeks, with step initiation (SI) tests at pre-training, post-training, 1-week and 1-month follow-ups. Primary outcomes were: baseline vertical ground reaction force (B-vGRF), response time (RT) to initiate anticipatory postural adjustment (APA), and the retention of B-VGRF and RT. Results: a-tDCS paired with a 4-week VST program results in a significant increase in paretic weight loading at 1-week follow up. Furthermore, a-tDCS in combination with VST led to significantly greater retention of paretic BWB compared with the sham group at 1 week post-training. Clinical implications: The preliminary findings suggest a 4-week VST results in improved paretic limb weight bearing (WB) during SI in PCS. Furthermore, VST combined with a-tDCS may lead to better retention of gait improvements (NCT04437251) (https://classic.clinicaltrials.gov/ct2/show/NCT04437251).

6.
Front Physiol ; 15: 1350051, 2024.
Article in English | MEDLINE | ID: mdl-38523807

ABSTRACT

Background: Optic nerve sheath diameter (ONSD) increases significantly at high altitudes, and is associated with the presence and severity of acute mountain sickness (AMS). Exposure to hypobaria, hypoxia, and coldness when hiking also impacts intraocular pressure (IOP). To date, little is known about ocular physiological responses in trekkers with myopia at high altitudes. This study aimed to determine changes in the ONSD and IOP between participants with and without high myopia (HM) during hiking and to test whether these changes could predict symptoms of AMS. Methods: Nine participants with HM and 18 without HM participated in a 3-day trek of Xue Mountain. The ONSD, IOP, and questionnaires were examined before and during the trek of Xue Mountain. Results: The ONSD values increased significantly in both HM (p = 0.005) and non-HM trekkers (p = 0.018) at an altitude of 1,700 m. In the HM group, IOP levels were greater than those in the non-HM group (p = 0.034) on the first day of trekking (altitude: 3,150 m). No statistically significant difference was observed between the two groups for the values of ONSD. Fractional changes in ONSD at an altitude of 1,700 m were related to the development of AMS (r pb = 0.448, p = 0.019) and the presence of headache symptoms (r pb = 0.542, p = 0.004). The area under the ROC curve for the diagnostic performance of ONSD fractional changes at an altitude of 1,700 m was 0.859 for predicting the development of AMS and 0.803 for predicting the presence of headache symptoms. Conclusion: Analysis of changes in ONSD at moderate altitude could predict AMS symptoms before an ascent to high altitude. Myopia may impact physiological accommodation at high altitudes, and HM trekkers potentially demonstrate suboptimal regulation of aqueous humor in such environments.

7.
Asian J Surg ; 47(6): 2623-2624, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38531735

ABSTRACT

TECHNIQUE: The surgical management for high-output postoperative chylothorax typically necessitates ligation of the thoracic duct (TD) above the leak site and/or sealing the leak with a clip. However, pinpointing these structures during subsequent surgeries can be challenging due to their variable course and the presence of traumatized tissues surrounding the leak area. In response to this, we have developed a novel, fluorescence-guided technique that significantly enhances intraoperative identification of the leak point and the TD. This method was applied in the case of a 52-year-old man suffering from refractory chylothorax following a previous lung cancer surgery. This study documents the surgical procedure and includes a video vignette for a comprehensive understanding. RESULTS: A bilateral inguinal lymph node injection of saline (10 mL), guided by ultrasound and containing 2.5 mg/mL indocyanine green (ICG), was administered 20 min prior to surgery. During thoracoscopic exploration, the leak point was precisely pinpointed in the right paratracheal area by transitioning from bright light to fluorescent mode. The TD was clearly identified, and upon ligation, there was no further leakage of fluorescent lymph, indicating a successful closure of the lymphatic structure. The surgery proceeded uneventfully, and the patient was able to resume oral intake on the third postoperative day. There was no evidence of recurring symptoms, leading to his discharge. CONCLUSION: The intralymphatic injection of ICG offers a rapid visualization of the TD's anatomy and can effectively pinpoint the leak point, even amidst traumatized tissues. Moreover, it provides prompt feedback on the efficacy of ligation.


Subject(s)
Chylothorax , Indocyanine Green , Postoperative Complications , Thoracic Surgery, Video-Assisted , Humans , Chylothorax/surgery , Chylothorax/etiology , Male , Middle Aged , Postoperative Complications/etiology , Postoperative Complications/surgery , Indocyanine Green/administration & dosage , Thoracic Surgery, Video-Assisted/methods , Fluorescence , Ligation/methods , Thoracic Duct/surgery , Lung Neoplasms/surgery , Surgery, Computer-Assisted/methods
8.
Clin Psychol Psychother ; 31(1): e2958, 2024.
Article in English | MEDLINE | ID: mdl-38358078

ABSTRACT

OBJECTIVE: Borderline personality disorder (BPD) with auditory hallucinations (AHs) may inadvertently be misdiagnosed with a primary psychotic disorder, such as schizophrenia (SZ). This misidentification can lead to challenges in providing effective psychological treatment. This review therefore aims to identify the phenomenological characteristics of AHs in BPD in comparison to SZ, as well as psychological interventions that explicitly target AHs in BPD. METHODS: A systematic review was conducted to summarise the existing evidence base regarding the phenomenological similarities and differences of AHs in BPD and SZ, along with the identification of psychological interventions for AHs in BPD. RESULTS: Eighteen studies were eligible for inclusion. Compared to the SZ group, BPD clients were characterised by more persistent and repetitive AHs, significantly more voice-related distress and appraisals of omnipotence, and an earlier age of onset of AHs. The BPD group also reported more severe depression and anxiety, a higher incidence of childhood trauma, and more negative self-schema. Cognitive Behaviour Therapy Coping Strategy Enhancement (CBT-CSE) might be a promising intervention to reduce AH-related distress in BPD, although further studies are required to determine its effectiveness. CONCLUSION: In order to prevent misdiagnosis of AHs in BPD, the DSM-5 may need to acknowledge the broader and more frequent occurrence of psychosis symptoms in BPD clients. Such clarification may enhance diagnostic practices and facilitate more timely access to treatment. There is also a need to develop and trial psychological interventions that explicitly target AHs in BPD.


Subject(s)
Borderline Personality Disorder , Cognitive Behavioral Therapy , Psychotic Disorders , Schizophrenia , Humans , Borderline Personality Disorder/complications , Borderline Personality Disorder/diagnosis , Borderline Personality Disorder/psychology , Hallucinations/complications , Hallucinations/diagnosis , Schizophrenia/complications , Schizophrenia/diagnosis , Psychotic Disorders/psychology
10.
Mol Cell Proteomics ; 23(2): 100710, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38154690

ABSTRACT

Antibody glycosylation plays a crucial role in the humoral immune response by regulating effector functions and influencing the binding affinity to immune cell receptors. Previous studies have focused mainly on the immunoglobulin G (IgG) isotype owing to the analytical challenges associated with other isotypes. Thus, the development of a sensitive and accurate analytical platform is necessary to characterize antibody glycosylation across multiple isotypes. In this study, we have developed an analytical workflow using antibody-light-chain affinity beads to purify IgG, IgA, and IgM from 16 µL of human plasma. Dual enzymes, trypsin and Glu-C, were used during on-bead digestion to obtain enzymatic glycopeptides and protein-specific surrogate peptides. Ultra-high-performance liquid chromatography coupled with triple quadrupole mass spectrometry was used in order to determine the sensitivity and specificity. Our platform targets 95 glycopeptides across the IgG, IgA, and IgM isotypes, as well as eight surrogate peptides representing total IgG, four IgG classes, two IgA classes, and IgM. Four stable isotope-labeled internal standards were added after antibody purification to calibrate the preparation and instrumental bias during analysis. Calibration curves constructed using serially diluted plasma samples showed good curve fitting (R2 > 0.959). The intrabatch and interbatch precision for all the targets had relative standard deviation of less than 29.6%. This method was applied to 19 human plasma samples, and the glycosylation percentages were calculated, which were comparable to those reported in the literature. The developed method is sensitive and accurate for Ig glycosylation profiling. It can be used in clinical investigations, particularly for detailed humoral immune profiling.


Subject(s)
Glycopeptides , Immunoglobulin G , Humans , Glycosylation , Immunoglobulin G/metabolism , Chromatography, High Pressure Liquid/methods , Mass Spectrometry , Glycopeptides/metabolism , Digestion , Immunoglobulin A , Immunoglobulin M
11.
Polymers (Basel) ; 15(20)2023 Oct 13.
Article in English | MEDLINE | ID: mdl-37896320

ABSTRACT

Polyetheretherketone (PEEK) is a promising biomaterial due to its excellent mechanical properties. Most PPEK manufacturing methods include additive manufacturing, injection molding, grinding, pulse laser drilling, or incremental sheet forming. Rotary friction welding (RFW) is a promising bonding technique in many industries. However, very few studies have focused on the RFW of PEEK. Conventionally, the number of revolutions is fixed during the welding process. Remarkably, the rotary friction welding of PEEK polymer rods using an innovative variable rotational speed is investigated in this study. The average bending strength of the welded part using a three-stage transformation rotational speed was enhanced by about 140% compared with a rotational speed of 1000 rpm. The advantage of computer numerical controlled RFW of PEEK using variable rotational speed is a reduced cycle time of RFW. A reduction in cycle time of about 6% can be obtained using the proposed RFW with a three-stage transformation rotational speed. The innovative approach provides low environmental pollution and high energy efficiency and complies with sustainable development goals.

12.
Biosens Bioelectron ; 241: 115648, 2023 Dec 01.
Article in English | MEDLINE | ID: mdl-37690354

ABSTRACT

Doping sorted graphene quantum dots (GQDs) with heteroatoms and functionalizing them with amino acid could improve their radiative recombination and two-photon properties-including their excitation-wavelength-independent photoluminescence from the ultraviolet to the near-infrared-I (NIR-I) region, absorption, quantum yield, absolute cross section, lifetime, and radiative-to-nonradiative decay ratio-under two-photon excitation (TPE) at a low excitation energy and short photoexcitation duration, as determined using a self-made optical microscopy system with a femtosecond Ti-sapphire laser. Four types of sorted GQDs were investigated: undoped GQDs, nitrogen-doped GQDs (N-GQDs), amino-functionalized GQDs (amino-GQDs), and N-doped and amino-functionalized GQDs (amino-N-GQDs). Among them, the sorted amino-N-GQDs are effective as a two-photon photosensitizer and generate the highest quantity of reactive oxygen species for the elimination of multidrug-resistant cancer cells through two-photon photodynamic therapy (PDT). Larger amino-N-GQDs result in a greater number of C-N and N-functionalities, leading to a superior photochemical effect and more favorable intrinsic luminescence properties, making the dots effective contrast agents for tracking and localizing cancer cells during in-depth bioimaging in a three-dimensional biological environment under TPE in the NIR-II region. Overall, this study highlights the potential of large amino-N-GQDs as a material for future application to dual-modality two-photon PDT and biomedical imaging.


Subject(s)
Biosensing Techniques , Graphite , Photochemotherapy , Quantum Dots , Graphite/chemistry , Lighting , Drug Resistance, Multiple , Quantum Dots/chemistry , Drug Resistance, Neoplasm , Photochemotherapy/methods
13.
Materials (Basel) ; 16(17)2023 Aug 22.
Article in English | MEDLINE | ID: mdl-37687431

ABSTRACT

To enhance the productivity and quality of optical-grade liquid silicone rubber (LSR) and an optical convex lens simultaneously, uniform vulcanization of the molding material is required. However, little has been reported on the uniform vulcanization of LSR in the heated cavity. This paper presents a conformal heating channel to enhance the temperature uniformity of the mold surface in the LSR injection molding. The curing rate of an optical convex lens was numerically investigated using Moldex3D molding simulation software. Two different sets of soft tooling inserts, injection mold inserts with conventional and conformal heating channels, were fabricated to validate the simulation results. The mold surface temperature uniformity was investigated by both numerical simulation and experiment. In particular, both a thermal camera and thermocouples were employed to measure the mold surface temperature after LSR injecting molding. It was found that the uniformity of the mold surface for LSR injection mold with the conformal heating channel was better. The average temperature of the mold surface could be predicted by the heating oil temperature according to the proposed prediction equation. The experimental results showed that the trend of the average temperature of five sensor modes was consistent with the simulation results. The error rate of the simulation results was about 8.31% based on the experimental result for the LSR injection mold with the conformal heating channel.

14.
Biomedicines ; 11(8)2023 Jul 27.
Article in English | MEDLINE | ID: mdl-37626617

ABSTRACT

OBJECTIVE: An increasing trend in the prevalence of gestational diabetes mellitus (GDM) has been reported in Taiwan. GDM has been linked to various adverse maternal outcomes over a long period, including cardiovascular disease (CVD) and chronic kidney disease (CKD). However, evidence implies that the effects of GDM on the mid-term surrogate risk factors for these diseases are limited. Furthermore, data from nationwide cohort studies are limited. The primary aim of this study was to investigate the risk of developing type 2 diabetes mellitus (T2DM), arterial hypertension (aHTN), and hyperlipidemia (HL) through a 5-year follow-up post-delivery of women with GDM in a nationwide cohort study in Taiwan. The second objective was to investigate the risk of developing insulin resistance syndrome (IRS)-related diseases, including CVD, acute myocardial infarction (AMI), peripheral artery occlusive disease (PAOD), non-alcoholic fatty liver diseases (NAFLD), and CKD. METHODS: This was a retrospective, population-based nationwide cohort study. The data source comprises a merge of the Birth Certificate Application Database (BCA) and the National Health Insurance Research Database in Taiwan. Women aged between 15 and 45 years who gave birth in Taiwan between 2004 and 2011 were included. Women who were enrolled and had a GDM diagnosis were assigned to the exposure group. Women who were enrolled without a GDM diagnosis were assigned to the comparison group. The relative risk of developing T2DM, aHTN, HL, and IRS-related diseases, including CVD, AMI, PAOD, NAFLD, and CKD, were analyzed and presented as hazard ratio (HR) through Cox regression and log-rank regression analyses. RESULTS: A total of 1,180,477 women were identified through the BCA database between 2004 and 2011. Of those, 71,611 GDM-diagnosed women and 286,444 women without GDM were included in the final analysis. After adjusting for age, pre-existing cancer, and parity, developing T2DM, aHTN, and HL were still significantly increased in the GDM group (HR and interquartile range (IQR): 2.83 (2.59, 3.08), 1.09 (1.01, 1.06), and 1.29 (1.20, 1.38), accordingly). CVD, NAFLD, and CKD had a very low incidence and showed insignificant results. CONCLUSION: Our findings provide nationwide cohort data showing that GDM increased the risk of developing T2DM, aHTN, and HL 5 years after delivery within the same group. The GDM complications and risk of CVD, AMI, PAOD, NAFLD, and CKD need further investigation.

15.
Entropy (Basel) ; 25(7)2023 Jul 19.
Article in English | MEDLINE | ID: mdl-37510032

ABSTRACT

Road segmentation is beneficial to build a vision-controllable mission-oriented self-driving bot, e.g., the Self-Driving Sweeping Bot, or SDSB, for working in restricted areas. Using road segmentation, the bot itself and physical facilities may be protected and the sweeping efficiency of the SDSB promoted. However, roads in the real world are generally exposed to intricate noise conditions as a result of changing weather and climate effects; these include sunshine spots, shadowing caused by trees or physical facilities, traffic obstacles and signs, and cracks or sealing signs resulting from long-term road usage, as well as different types of road materials, such as cement or asphalt; all of these factors greatly influence the effectiveness of road segmentation. In this work, we investigate the extension of Primordial U-Net by the proposed EnRDeA U-Net, which uses an input channel applying a Residual U-Net block as an encoder and an attention gate in the output channel as a decoder, to validate a dataset of intricate road noises. In addition, we carry out a detailed analysis of the nets' features and segmentation performance to validate the intricate noises dataset on three U-Net extensions, i.e., the Primordial U-Net, Residual U-Net, and EnRDeA U-Net. Finally, the nets' structures, parameters, training losses, performance indexes, etc., are presented and discussed in the experimental results.

16.
Polymers (Basel) ; 15(13)2023 Jun 29.
Article in English | MEDLINE | ID: mdl-37447514

ABSTRACT

Liquid silicone rubber (LSR) techniques are experiencing exponential growth, particularly in the field of high technology due to the low-temperature flexibility, superior heat stability, chemical resistance, and aging resistance of LSR components. Enhancing the curing rate of LSR parts in liquid silicone rubber injection molding is an important research topic. In this study, an injection mold with high energy efficiency of vulcanization for the liquid silicone rubber injection molding of a fisheye lens was developed and implemented. The LSR injection mold has a conformal heating channel (CHC) and conformal cooling channel (CCC) simultaneously. The function of CHC is to enhance the curing rate of a fisheye lens in the LSR injection molding to meet the requirements of sustainable manufacturing. The curing rates of a fisheye lens were numerically examined using the Moldex3D molding simulation software. It was found that the curing rate of the fisheye optical lens cured by injection mold with CHC was better than that of the injection mold with a conventional heating channel. The curing efficiency could be increased by about 19.12% when the heating oil temperature of 180 °C was used to cure the fisheye optical lens. The simulation results showed that the equation y = -0.0026x3 + 1.3483x2 - 232.11x + 13,770 was the most suitable equation for predicting the curing time (y) through the heating oil temperature (x). It was found that the trend of the experimental results was consistent with the simulation results. In addition, the equation y = -0.0656x2 + 1.5827x - 0.894 with the correlation coefficient of 0.9974 was the most suitable equation for predicting the volumetric shrinkage of the fisheye optical lens (y) through the heating oil temperature (x). The volume shrinkage of the fisheye optical lens cured by injection mold with CHC was very similar to that of the injection mold with a conventional heating channel. The maximum volume shrinkage of the fisheye optical lens cured at 180 °C was about 8.5%.

17.
Forensic Sci Int ; 349: 111776, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37399775

ABSTRACT

Because of its hallucinogenic and dissociative effects, ketamine is often abused for recreational purposes. Thus, the seizure of ketamine manufacturing units is crucial for preventing drug abuse. The precursors popularly used for ketamine synthesis include 1-[(2-chlorophenyl)(methylimino)methyl]cyclopentanol hydrochloride and 2-(2-chlorophenyl)-2-nitrocyclohexanone (2-CPNCH). Herein, we report a case of the seizure of a ketamine manufacturing unit by law enforcement officers. The seized materials were sent to our laboratory for confirmation. We found that 2-CPNCH was used as the precursor. Using zinc powder and formic acid, 2-CPNCH was reduced to norketamine. Through the Eschweiler-Clarke reaction, norketamine was reacted with formaldehyde and formic acid to synthesize ketamine; the advantages of this process are a short duration of reaction and the requirement of small amounts of chemicals. We further identified an impurity (N-methyl ketamine), which was used as a marker to validate this new process of ketamine synthesis. To the best of our knowledge, this study is the first to report illegal ketamine synthesis through the Eschweiler-Clarke reaction when using 2-CPNCH as the precursor. Our findings inform law enforcement officers and forensic practitioners about this new process of ketamine synthesis.

18.
J Phys Chem Lett ; 14(1): 122-131, 2023 Jan 12.
Article in English | MEDLINE | ID: mdl-36574643

ABSTRACT

The photon energy-dependent selectivity of photocatalytic CO2-to-CO conversion by CsPbBr3 nanocrystals (NCs) and CsPbBr3/g-C3N4 nanoheterostructures (NHSs) was demonstrated for the first time. The surficial capping ligands of CsPbBr3 NCs would adsorb CO2, resulting in the carboxyl intermediate to process the CO2-to-CO conversion via carbene pathways. The type-II energy band structure at the heterojunction of CsPbBr3/g-C3N4 NHSs would separate the charge carriers, promoting the efficiency in photocatalytic CO2-to-CO conversion. The electron consumption rate of CO2-to-CO conversion for CsPbBr3/g-C3N4 NHSs was found to intensively depend on the rate constant of interfacial hole transfer from CsPbBr3 to g-C3N4. An in situ transient absorption spectroscopy investigation revealed that the half-life time of photoexcited electrons in optimized CsPbBr3/g-C3N4 NHS was extended two times more than that in the CsPbBr3 NCs, resulting in the higher probability of charge carriers to carry out the CO2-to-CO conversion. The current work presents important and novel insights of semiconductor NHSs for solar energy-driven CO2 conversion.

19.
Int J Mol Sci ; 23(23)2022 Nov 27.
Article in English | MEDLINE | ID: mdl-36499166

ABSTRACT

Cilostazol is an antiplatelet agent with vasodilating effects that functions by increasing the intracellular concentration of cyclic adenosine monophosphate. We have previously shown that cilostazol has favorable effects on angiogenesis. However, there is no study to evaluate the effects of cilostazol on adiponectin. We investigated the effects of cilostazol on angiogenesis in diabetes in vitro and in vivo through adiponectin/adiponectin receptors (adipoRs) and the sirtuin 1 (SIRT1)/AMP-activated protein kinase (AMPK) signaling pathway. Human umbilical vein endothelial cells (HUVECs) and human aortic smooth muscle cells (HASMCs) were cocultured under high glucose (HG) conditions. Adiponectin concentrations in the supernatants were significantly increased when HASMCs were treated with cilostazol but not significantly changed when only HUVECs were treated with cilostazol. Cilostazol treatment enhanced the expression of SIRT1 and upregulated the phosphorylation of AMPK in HG-treated HUVECs. By sequential knockdown of adipoRs, SIRT1, and AMPK, our data demonstrated that cilostazol prevented apoptosis and stimulated proliferation, chemotactic motility, and capillary-like tube formation in HG-treated HUVECs through the adipoRs/SIRT1/AMPK signaling pathway. The phosphorylation of downstream signaling molecules, including acetyl-CoA carboxylase (ACC) and endothelial nitric oxide synthase (eNOS), was downregulated when HUVECs were treated with a SIRT1 inhibitor. In streptozotocin-induced diabetic mice, cilostazol treatment could improve blood flow recovery 21-28 days after inducing hindlimb ischemia as well as increase the circulating of CD34+CD45dim cells 14-21 days after operation; moreover, these effects were significantly attenuated by the knockdown of adipoR1 but not adipoR2. The expression of SIRT1 and phosphorylation of AMPK/ACC and Akt/eNOS in ischemic muscles were significantly attenuated by the gene knockdown of adipoRs. Cilostazol improves HG-induced endothelial dysfunction in vascular endothelial cells and enhances angiogenesis in diabetic mice by upregulating the expression of adiponectin/adipoRs and its SIRT1/AMPK downstream signaling pathway.


Subject(s)
Diabetes Mellitus, Experimental , Sirtuin 1 , Animals , Humans , Mice , Acetyl-CoA Carboxylase/metabolism , Adiponectin/metabolism , AMP-Activated Protein Kinases/metabolism , Cilostazol/pharmacology , Diabetes Mellitus, Experimental/metabolism , Human Umbilical Vein Endothelial Cells/metabolism , Ischemia/metabolism , Phosphorylation , Receptors, Adiponectin/genetics , Receptors, Adiponectin/metabolism , Signal Transduction , Sirtuin 1/genetics , Sirtuin 1/metabolism , Neovascularization, Pathologic
20.
Medicine (Baltimore) ; 101(47): e31492, 2022 Nov 25.
Article in English | MEDLINE | ID: mdl-36451391

ABSTRACT

BACKGROUND: Warm needling is a type of traditional Chinese medicine (TCM), which uses burned moxa to generate warmth and exerts a therapeutic effect on human skin. Additionally, based on TCM theory, warm needling could improve deficiency-cold syndrome. Research has found that warm needling has analgesic effects as well as effects on the immune system, endocrine system, nervous system, and lower urinary tract symptoms. However, the mechanism of warm needling on the meridians is not fully understood. In modern studies, the electric characteristics of the meridians have been discovered and the combination of semiconductor and TCM theory could explain the meridian phenomena through physics. However, there is no known research exploring the relationship between thermal effect and electric property on the meridians. METHODS: A total of 30 healthy participants older than 20 years of age will be recruited for this study. The participants would first be administered acupuncture, following which the electric characteristics will be measured using the semiconductor analyzer Agilent B1500A/Agilent 4156C. The visual analog score (VAS) will also be rated. Thereafter, a burned moxa will be added to the acupuncture needles as a method for warm needling. The electric characteristics and VAS will be measured again. We will use the paired t-test and repeated measure two-way ANOVA to compare the electric characteristics and VAS before and after warm needling in each participant. OBJECTIVES: This protocol aims to explore the thermal effect on the electric characteristics of meridians in a warm needling model and provide a scientific explanation of TCM through the aspect of physics.


Subject(s)
Acupuncture Therapy , Meridians , Moxibustion , Humans , Vascular Surgical Procedures , Prospective Studies , Observational Studies as Topic
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