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1.
Eur J Clin Invest ; : e14226, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632688

RESUMO

Intervertebral disc degeneration (IVDD) is a common chronic orthopaedic disease in orthopaedics that imposes a heavy economic burden on people and society. Although it is well established that IVDD is associated with genetic susceptibility, ageing and obesity, its pathogenesis remains incompletely understood. Previously, IVDD was thought to occur because of excessive mechanical loading leading to destruction of nucleus pulposus cells (NPCs), but studies have shown that IVDD is a much more complex process associated with inflammation, metabolic factors and NPCs death and can involve all parts of the disc, characterized by causing NPCs death and extracellular matrix (ECM) degradation. The damage pattern of NPCs in IVDD is like that of some programmed cell death, suggesting that IVDD is associated with programmed cell death. Although apoptosis and pyroptosis of NPCs have been studied in IVDD, the pathogenesis of intervertebral disc degeneration can still not be fully elucidated by using only traditional cell death modalities. With increasing research, some new modes of cell death, PANoptosis, ferroptosis and senescence have been found to be closely related to intervertebral disc degeneration. Among these, PANoptosis combines essential elements of pyroptosis, apoptosis and necroptosis to form a highly coordinated and dynamically balanced programmed inflammatory cell death process. Furthermore, we believe that PANoptosis may also crosstalk with pyroptosis and senescence. Therefore, we review the progress of research on multiple deaths of NPCs in IVDD to provide guidance for clinical treatment.

2.
Soft Matter ; 20(12): 2823-2830, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38451223

RESUMO

Amphiphilic asymmetric comb-like copolymers (AACCs) exhibit distinct self-assembly behaviours due to their unique architecture. However, the synthetic difficulties of well-defined AACCs have prohibited a systematic understanding of the architecture-morphology relationship. In this work, we conducted dissipative particle dynamics simulations to investigate the self-assembly behaviours of AACCs with responsive rigid side chains in selective solvents. The effects of side chain length, number of branches, and spacers on the morphology of aggregates were investigated by mapping out morphology diagrams. Besides, the numbers and surface areas of aggregates clearly depicted the morphological transitions during the self-assembly process. Moreover, the rod-to-coil conformation transitions were simulated to explore the stimuli-responsive behaviour of the AACCs with responsive rigid side chains by adjusting the bond angle parameter of the rigid chains. The results indicated that without the support of the rigid chains, the assembly structure collapsed, leading to the tube-to-channelized micelles and one-compartment-to-multicompartment vesicle morphology transformations. The simulation results are consistent with earlier experimental results, which can provide theoretical guidance for assembly toward desired nanostructures.

3.
Appl Opt ; 63(7): 1794, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38437282

RESUMO

This publisher's note corrects an error in Appl. Opt.63, 1411 (2024)APOPAI0003-693510.1364/AO.512229.

4.
Appl Opt ; 63(5): 1411-1417, 2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38437322

RESUMO

Because of the high efficiency of frequency conversion and beam-target coupling, a fourth harmonic (4ω) laser has a splendid application prospect in a high-power laser facility. The polarization smoothing (PS) crystal is preferably after the frequency conversion crystal to flexibly obtain the best uniformity illumination of the target. However, as a high irradiance 4ω laser beam propagates through the PS crystal, the transverse stimulated Raman scattering (TSRS) effect of the PS crystal will be stronger, resulting in significant energy dissipation and crystal damage. This paper proposes a novel, to the best of our knowledge, fourth harmonic generation (FHG) scheme based on an orthogonal cascade of the DKDP crystals. This orthogonal cascaded FHG (OC-FHG) scheme employs two cascaded FHG crystals with orthogonal optical axes, and the PS crystal is in the middle. The PS crystal can rotate the polarization direction of the 2ω laser by 90°, while the polarization direction of the 4ω laser is maintained to a great extent. This OC-FHG scheme realizes the FHG by two steps, and the laser intensity at the PS crystal cuts down nearly 50%. The output intensity of the 4ω laser can be increased from 1.8G W/c m 2 to about 3.6G W/c m 2 under the condition of effectively inhibiting the TSRS effect. Meanwhile, the output 4ω laser contains two orthogonal polarized beams realizing in-beam polarization smoothing instantaneously. In addition, the novel FHG scheme can also have a high conversion efficiency and bandwidth tolerance.

5.
Sensors (Basel) ; 24(2)2024 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-38257445

RESUMO

This paper proposed a real-time fault diagnostic method for hydraulic systems using data collected from multiple sensors. The method is based on a proposed multi-sensor convolutional neural network (MS-CNN) that incorporates feature extraction, sensor selection, and fault diagnosis into an end-to-end model. Both the sensor selection process and fault diagnosis process are based on abstract fault-related features learned by a CNN deep learning model. Therefore, compared with the traditional sensor-and-feature selection method, the proposed MS-CNN can find the sensor channels containing higher-level fault-related features, which provides two advantages for diagnosis. First, the sensor selection can reduce the redundant information and improve the diagnostic performance of the model. Secondly, the reduced number of sensors simplifies the model, reducing communication burden and computational complexity. These two advantages make the MS-CNN suitable for real-time hydraulic system fault diagnosis, in which the multi-sensor feature extraction and the computation speed are both significant. The proposed MS-CNN approach is evaluated experimentally on an electric-hydraulic subsea control system test rig and an open-source dataset. The proposed method shows obvious superiority in terms of both diagnosis accuracy and computational speed when compared with traditional CNN models and other state-of-the-art multi-sensor diagnostic methods.

6.
Aesthetic Plast Surg ; 48(6): 1210-1217, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37783864

RESUMO

The contour of the neck and shoulder is defined by the trapezius muscle (TM). Beyond facial procedures, botulinum toxin A (BoNT-A) injections has been increasingly adopted to create a smooth shoulder line. Several studies described the intramuscular nerve branching and the pattern of perforating branch of the accessory nerve in the trapezius muscle, providing essential information for botulinum neurotoxin injection. To this date, research groups seldom perform clinical investigations, especially randomized controlled trials, that demonstrates whether BoNT-A injections using the nerve distribution method for aesthetic purposes is more effective. Patients met the criteria for inclusion were randomized to either the Nerve Distribution group (ND group) or control group. Control group patients received injection using the conventional method while ND group patients received the nerve distribution method. Photographic and ultrasonographic evaluations were carried out at baseline, one month, three months, and six months after the procedure. Patients were also required to complete a questionnaire to evaluate their feedbacks to the injection. After screening, 30 healthy young Chinese women were included. At one-month follow-up, no statistically significant difference was observed between the two methods. At the three-month follow-up, the reduction of the TM thickness for the ND group (0.21 ± 0.09 cm) was more than that for the control group (0.27 ± 0.08 cm), with p = 0.047*. Similar differences were observed for the reduction of the shoulder area proportion (p = 0.031*) and the shoulder angle (p = 0.035*). At the six-month follow-up, the reduction in TM thickness in the ND group (0.2 ± 0.09 cm) was more than that of the control group (0.28 ± 0.06 cm), with p = 0.041*. The global aesthetic improvement scale feedbacks of the two methods showed no significant difference (3.4 ± 0.71 vs 3.8 ± 0.91, p = 0.207). The patients did not experience severe side effects. Compared to the conventional injection method, the nerve distribution method is more effective in reducing the trapezius muscle thickness, shoulder area proportion, and shoulder angle at three months, and shows longer lasting effects. The results of this study introduce unique insights into the design and tailoring of treatment protocols for shoulder-line contouring using BoNT-A.Level of Evidence I This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Assuntos
Toxinas Botulínicas Tipo A , Músculos Superficiais do Dorso , Humanos , Feminino , Injeções , Hipertrofia/tratamento farmacológico , Resultado do Tratamento , Ensaios Clínicos Controlados Aleatórios como Assunto
7.
Aesthetic Plast Surg ; 48(10): 1956-1963, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38238567

RESUMO

BACKGROUND: This study was conducted to compare the effects of heat preservation by two recommended methods, heated infiltration solutions and forced-air heating blankets, in patients undergoing liposuction under general anesthesia. METHODS: Forty patients were divided into four groups based on whether heated infiltration solutions or forced-air heating blankets were used. Group A received general anesthesia liposuction plastic surgery routine temperature care. Based on the care measures of group A, heated infiltration solutions were used in group B; forced-air heating blanket was used in group C; and heated infiltration solutions and forced-air heating blankets were both used in group D. The primary end point was intraoperative and perioperative temperature measured with an infrared tympanic membrane thermometer. Secondary end points included surgical outcomes, subjective experience, and adverse events. RESULTS: Compared with group A, the intraoperative body temperatures of groups B, C, and D were significantly higher, indicating that the two intervention methods were helpful on increasing the core body temperature. Pairwise comparisons of these three groups showed that there was no significant difference between group C and group D. However, using forced-air heating blankets had a marked effect compared with using heated infiltration solutions alone at three time points. The same trend could be seen in other surgical outcomes. CONCLUSIONS: Heated infiltration solutions and forced-air heating blankets could reduce the incidence of intraoperative hypothermia and improve patients' prognosis after liposuction under general anesthesia. Compared with the heated infiltration fluid, the forced-air heating blanket may have a better thermal insulation effect. LEVEL OF EVIDENCE I: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Assuntos
Hipotermia , Complicações Intraoperatórias , Lipectomia , Humanos , Lipectomia/métodos , Lipectomia/efeitos adversos , Feminino , Adulto , Hipotermia/prevenção & controle , Hipotermia/etiologia , Masculino , Complicações Intraoperatórias/prevenção & controle , Complicações Intraoperatórias/etiologia , Pessoa de Meia-Idade , Anestesia Geral/métodos , Roupas de Cama, Mesa e Banho , Resultado do Tratamento , Adulto Jovem , Temperatura Alta , Medição de Risco
8.
Aesthet Surg J ; 44(8): 880-888, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38377399

RESUMO

BACKGROUND: The depressor anguli oris muscle (DAO) is a pivotal treatment target when creating a harmonic jawline. However, evidence of its live morphology remains scarce. OBJECTIVES: In this study we aimed to reevaluate the DAO with a facile ultrasound analysis and thereby guide safer and more effective botulinum toxin type A (BTX-A) injection. METHODS: A prospective ultrasound assessment was conducted in 41 patients. Morphology of the DAO and its relative position to neighboring structures were appraised at the ubiquitous facial landmark, the labiomandibular fold (LMF). Three-dimensional images were captured before and after the patient received the BTX-A injection based on sonographic evidence. RESULTS: The skin-to-muscle depths of the DAO on average (measured from the medial to lateral border) were 5.26, 5.61, and 8.42 mm. The DAO becomes thinner and wider from zone 1 to zone 3 (P < .001). Overlapping lengths of the DAO and the depressor labii inferioris increased from zone 1 to zone 3: 4.74, 9.68, 14.54 mm (P < .001). The medial border of the DAO was located at 4.33, 6.12, 8.90 mm medial to the LMF (zone 1-3), and no muscle fibers of the DAO were observed in zone 1 or zone 2 in nearly one-third of patients. Improvement of the mouth corner downturn angle upon receiving BTX-A injection at zones 2 and 3 were 88.3%, 32.3%, and 14.7% for the neutral, maximum smile, and down-turning mouth corner expressions. CONCLUSIONS: This work established an informative ultrasound portrait of the DAO and structures in the perioral region, which suggested the LMF as a convenient landmark for locating the DAO. Injection at the middle and lower thirds of the LMF at a 4- to 5-mm depth is recommended.


Assuntos
Toxinas Botulínicas Tipo A , Técnicas Cosméticas , Músculos Faciais , Fármacos Neuromusculares , Rejuvenescimento , Ultrassonografia , Humanos , Toxinas Botulínicas Tipo A/administração & dosagem , Estudos Prospectivos , Feminino , Músculos Faciais/diagnóstico por imagem , Músculos Faciais/efeitos dos fármacos , Músculos Faciais/anatomia & histologia , Pessoa de Meia-Idade , Adulto , Ultrassonografia/métodos , Masculino , Fármacos Neuromusculares/administração & dosagem , Injeções Intramusculares/métodos , Idoso , Imageamento Tridimensional , Resultado do Tratamento , Pontos de Referência Anatômicos
9.
Int Wound J ; 21(1): e14559, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38272806

RESUMO

Localised scleroderma predominantly affects the skin with an unknown aetiology. Despite its clinical importance, no comprehensive bibliometric analysis has been conducted to assess the existing research landscape and future prospects for localised scleroderma. The articles related to localised scleroderma were retrieved from the WoSCC database and analysed by VOSviewer 1.6.10.0 (Leiden University, Netherlands), CiteSpace 6.1.R1 (Dreiser University, USA), and HistCite 2.1 (New York, United States). 2049 research papers pertaining to localised scleroderma spanning the years from 1993 to 2022 were extracted from the WoSCC database. The United States exhibited the highest productivity with 644 papers, accounting for 31.43% of the total output, followed by Germany with 206 papers (10.05%) and Italy with 200 papers (9.76%). Regarding academic institutions and journals, the University of Texas System and Dermatology published the most significant number of papers, and Professor Ihn, H emerged as the most prolific contributor among scholars. The top 10 cited references primarily concentrated on the diagnosis and treatment of localised scleroderma. "Phototherapy" and "methotrexate (MTX)" surfaced as the most recent and noteworthy keywords, representing the research hotspots in the domain of localised scleroderma. This bibliometric analysis furnishes valuable insights into the contemporary research landscape of localised scleroderma.


Assuntos
Esclerodermia Localizada , Humanos , Esclerodermia Localizada/terapia , Pele , Bibliometria , Bases de Dados Factuais , Alemanha
10.
Phys Chem Chem Phys ; 25(37): 25309-25321, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37702094

RESUMO

The effects of the structural units and blending ratio on the crystallization behavior of blends of polyamide 4 (PA4) with polyamide 56 (PA56) and polyamide 11 (PA11) were studied using molecular dynamics simulations and non-isothermal crystallization kinetics. The simulation results show that the crystallinity of PA4/PA56 blends (B4/56) with a PA56 content of 30-50% was 3.5-10.8% lower than that of B4/56 with a PA56 content of 20%, and the crystallinity of PA4/PA11 blends (B4/11) decreased by 9.5% as PA11 content increased from 20% to 50%. The experimental results show that both B4/56 and B4/11 form PA4- and PA56-rich (PA11-rich) phases through crystallization-induced phase separation. The interplanar spacing of the PA4-rich phase of B4/56 changed relative to that of PA4, indicating that some PA56 entered the PA4-rich phase unit cell. As the PA56 content increased from 20% to 50%, the crystallinity of B4/56 decreased by 11.2%, and the crystallization-induced phase separation grew distinct. The B4/56 with a higher PA4 content crystallized more easily. As the PA11 content increased from 20% to 50%, the crystallinity of B4/11 decreased by 12.5%, and PA11 barely participated in the crystallization of the PA4-rich phase. The blending ratio had no significant effect on the crystallization rate and crystal-growth degree of B4/11, and the non-isothermal crystallization activation energy of B4/11 was significantly higher than that of B4/56, indicating that the crystallization ability of the B4/11 blend system is worse. This study provides a theoretical basis for the design and performance regulation of PA4-based polyamide blends.

11.
BMC Pregnancy Childbirth ; 23(1): 507, 2023 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-37434108

RESUMO

BACKGROUND: Intestinal obstruction is an uncommon non-obstetric condition during pregnancy which may cause maternal and fetal mortality. Clinicians are confronted with challenges in diagnosis and treatment of intestinal obstruction due to the overlapping symptoms, concerns over radiological evaluation, and surgical risks. CASE PRESENTATION: We reported a 39-year old, gravida 7, para 2, woman who suffered from acute intestinal obstruction at 34 weeks of gestation. Ultrasonography and abdominal computed tomography were applied for intestinal obstruction diagnose. Conservative treatment was initially attempted. But following ultrasound found the absence of fluid in the amniotic sac and the patient showed no improvement in clinical symptoms. An emergency caesarean section was then performed. Intra-operative assessment showed dense adhesion between the left wall of uterus and omentum, descending colon, and sigmoid colon. After adhesion dialysis, uterine rupture with complete opening of the uterine wall at the site of left uterine cornua was found without active bleeding. The uterine rupture was then repaired. CONCLUSIONS: Although uncommon during pregnancy, clinical suspicion of bowel obstruction is necessary especially in women with a history of abdominal surgery. Surgical intervention is indicated when conservative therapy fails and when there are signs of abnormal fetal conditions and worsened symptoms.


Assuntos
Obstrução Intestinal , Perfuração Uterina , Ruptura Uterina , Gravidez , Feminino , Humanos , Adulto , Perfuração Uterina/complicações , Ruptura Uterina/etiologia , Ruptura Uterina/cirurgia , Cesárea , Obstrução Intestinal/diagnóstico por imagem , Obstrução Intestinal/etiologia , Obstrução Intestinal/cirurgia , Útero
12.
BMC Pregnancy Childbirth ; 23(1): 244, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37046188

RESUMO

BACKGROUND: The findings of the association of vaginal flora with preterm birth (PTB) or prelabor rupture of membranes (PROM) were conflicts. Moreover, vaginal flora was different by ethnicity and the evidence from China was limited. METHODS: This study was a nested case control study, based on Yiwu birth cohort. We assessed vaginal microbiota in the second or third trimester, using 16S rDNA Amplicon Sequencing and explored the association between the diversity and composition of vaginal flora and PTB or PROM. RESULTS: We finally included 144 pregnant women. In present study, the alpha diversity of TPROM (Term prelabor rupture of membranes) samples was lower than that of full term samples (Chao1 index: P < 0.05). When we further categorized PTB (Preterm birth) into SPB (PTB without PROM) and PPROM (Preterm prelabor rupture of membranes), there was no difference between SPB and full term. In addition, we found that the proportion of PCoA2 in TPROM group was different from that in full term group and preterm group. The difference between groups was significant according to anosim analysis (R = 0.059, P < 0.001). With LEfSe (Linear discriminant analysis Effect Size) analysis, we found that the abundance of Lactobacillus in the vaginal flora of pregnant women with preterm birth was the highest (P = 0.003). CONCLUSION: In Chinese pregnant women, the alpha diversity in TPROM group was significantly lower than that in both PTB and full term group. However, there was no difference between PTB and full term. Lactobacillus was the most abundant in preterm birth group. More studies should be conducted to confirm our findings.


Assuntos
Ruptura Prematura de Membranas Fetais , Nascimento Prematuro , Vagina , Feminino , Humanos , Recém-Nascido , Gravidez , Estudos de Casos e Controles , Ruptura Prematura de Membranas Fetais/epidemiologia , Terceiro Trimestre da Gravidez , Nascimento Prematuro/epidemiologia , Vagina/microbiologia
13.
Gerontology ; 69(11): 1315-1329, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37717573

RESUMO

INTRODUCTION: Ovarian aging is characterized by a gradual decline in quantity and quality of oocytes and lower chance of fertility. Better understanding the genetic modulation during ovarian aging can further address available treatment options for aging-related ovarian diseases and fertility preservation. METHODS: A novel technique spatial transcriptomics (ST) was used to investigate the spatial transcriptome features of rat ovaries. Transcriptomes from ST spots in the young and aged ovaries were clustered using differentially expressed genes. These data were analyzed to determine the spatial organization of age-induced heterogeneity and potential mechanisms underlying ovarian aging. RESULTS: In this study, ST technology was applied to profile the comprehensive spatial imaging in young and aged rat ovary. Fifteen ovarian cell clusters with distinct gene-expression signatures were identified. The gene expression dynamics of granulosa cell clusters revealed three sub-types with sequential developmental stages. Aged ovary showed a significant decrease in the number of granulosa cells from the antral follicle. Besides, a remarkable rearrangement of interstitial gland cells was detected in aging ovary. Further analysis of aging-associated transcriptional changes revealed that the disturbance of oxidative pathway was a crucial factor in ovarian aging. CONCLUSIONS: This study firstly described an aging-related spatial transcriptome changes in ovary and identified the potential targets for prevention of ovarian aging. These data may provide the basis for further investigations of the diagnosis and treatment of aging-related ovarian disorders.


Assuntos
Antioxidantes , Ovário , Ratos , Feminino , Animais , Ovário/metabolismo , Antioxidantes/farmacologia , Transcriptoma , Folículo Ovariano/metabolismo , Envelhecimento/genética
14.
Sensors (Basel) ; 23(8)2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37112498

RESUMO

This study explores the use of Multi-Objective Genetic Algorithm (MOGA) for thermodynamic characteristics of serrated plate-fin heat exchanger (PFHE) under numerical simulation method. Numerical investigations on the important structural parameters of the serrated fin and the j factor and the f factor of PFHE are conducted, and the experimental correlations about the j factor and the f factor are determined by comparing the simulation results with the experimental data. Meanwhile, based on the principle of minimum entropy generation, the thermodynamic analysis of the heat exchanger is investigated, and the optimization calculation is carried out by MOGA. The comparison results between optimized structure and original show that the j factor increases by 3.7%, the f factor decreases by 7.8%, and the entropy generation number decreases by 31%. From the data point of view, the optimized structure has the most obvious effect on the entropy generation number, which shows that the entropy generation number can be more sensitive to the irreversible changes caused by the structural parameters, and at the same time, the j factor is appropriately increased.

15.
Aesthetic Plast Surg ; 47(5): 2029-2036, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-36513879

RESUMO

BACKGROUND: Patients nowadays seek medical reduction of the upper trapezius muscle to achieve aesthetic pleasing necklines. Botulinum toxin type A (BoNT-A), a neurotoxin that reduces the force of muscle contraction, is widely used for shoulder contouring. However, detailed metrical data are lacking to guide clinical injection. METHODS: Forty healthy young women were enrolled. All subjects were seated for point marking and measuring of trapezius muscle (TM) anatomical data. At marked locations, the thickness of the subcutaneous tissue, the thickness of the TM, the TM's anterior border, and the depth from the skin surface to the middle of TM were measured using a real-time ultrasound scanner. In addition, photos were taken to assess the shoulder area proportion and shoulder angle. RESULTS: The shoulder area size among participants was 90 ± 15.2 cm2, the average area proportion was 0.55 ± 0.1, and the shoulder angle was 23.12° ± 2.9°. Ultrasonography data reveal that the thickness of the subcutaneous tissue, the thickness of the TM, and the depth from the skin surface to the middle of TM all thickened from the anterior line to the posterior line (P < 0.001). The length of the TM extending forward was 1.47 ± 0.4 cm (range 0.51-1.31 cm). To better evaluate the appearance of the trapezius muscle, we constructed a grading system correlated to shoulder angle. CONCLUSION: In this study, ultrasonography and photos were applied to assess the TM's anatomical features. Trapezius hypertrophy was described on a scale from 0 to 2 based on the shoulder angle. The findings of the present study provide a practical clinical guidance for precise and efficient BoNT-A administration. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Assuntos
Toxinas Botulínicas Tipo A , Músculos Superficiais do Dorso , Humanos , Feminino , Músculos Superficiais do Dorso/diagnóstico por imagem , Contração Muscular , Injeções
16.
Environ Geochem Health ; 45(8): 6693-6711, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37355494

RESUMO

The direct discharge of wastewater can cause severe damage to the water environment of the surface water. However, the influence of dissolved organic matter (DOM) present in wastewater on the allocation of DOM, nitrogen (N), and phosphorus (P) in rivers remains largely unexplored. Addressing the urgent need to monitor areas affected by direct wastewater discharge in a long-term and systematic manner is crucial. In this paper, the DOM of overlying water and sediment in the WWTPs-river-integrated area was characterized by ultraviolet-visible absorption spectroscopy (UV-vis), three-dimensional excitation-emission matrix combined with parallel factor (PARAFAC) method. The effects of WWTPs on receiving waters were investigated, and the potential link between DOM and N, P pollution was explored. The pollution risk was fitted and predicted using a spectral index. The results indicate that the improved water quality index (IWQI) is more suitable for the WWTPs-river integration zone. The DOM fraction in this region is dominated by humic-like matter, which is mainly influenced by WWTPs drainage as well as microbial activities. The DOM fractions in sediment and overlying water were extremely similar, but fluorescence intensity possessed more significant spatial differences. The increase in humic-like matter facilitates the production and preservation of P and also inhibits nitrification, thus affecting the N cycle. There is a significant correlation between DOM fraction, fluorescence index, and N, P. Fluorescence index (FI) fitting of overlying water DOM predicted IWQI and trophic level index, and a(254) fitting of sediment DOM predicted nitrogen and phosphorus pollution risk (FF) with good results. These results contribute to a better understanding of the impact of WWTPs on receiving waters and the potential link between DOM and N and P pollution and provide new ideas for monitoring the water environment in highly polluted areas.


Assuntos
Rios , Águas Residuárias , Rios/química , Matéria Orgânica Dissolvida , Espectrometria de Fluorescência , Nitrogênio/análise , Fósforo , Substâncias Húmicas/análise
17.
Soft Matter ; 18(20): 3910-3916, 2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35536292

RESUMO

We conducted a computational study on the self-assembly behavior of sequence-controlled amphiphilic copolymers with alternating rod and coil pendants. Complex self-assembled morphologies, such as onion-like vesicles with two layers, can be generated by introducing rod pendants. The amphiphilic alternating copolymers self-assemble into onion-like vesicles through a fusion process of tiny micelles and a bending operation of disk-like micelles with double layers. A stimuli-responsive simulation shows that the cylindrical vesicles can transform into onion-like vesicles by a rod-to-coil conformation transition of rigid pendants. Inspired by this finding, we conducted a drug-loading simulation by adding two reactive drugs at different stages and found that the onion-like vesicles can almost completely isolate two drugs. This work provides theoretical guidance on the self-assembly of amphiphilic alternating copolymers with rod and coil pendants for future experimental design.


Assuntos
Micelas , Polímeros , Conformação Molecular
18.
Chem Rev ; 120(9): 4111-4140, 2020 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-32212685

RESUMO

In recent years, the self-assembly of copolymer micelles has become an appealing frontier of supramolecular chemistry as a strategy to construct superstructures with multiple levels of complexity. The assembly of copolymer micelles is a form of higher-level self-assembly occurring at the nanoscale level where the building blocks are preassembled micelles. Compared to one-step hierarchical self-assembly, this assembly strategy is superior for manipulating multilevel architectures because the structures of the building blocks and higher-order hierarchies can be regulated separately in the first and higher-level assembly, respectively. However, despite the substantial advances in the self-assembly of copolymer micelles in recent years, universal laws have not been comprehensively summarized. This review article aims to provide an overview of the current progress and developing prospects of the self-assembly of copolymer micelles. In particular, the significant role of theoretical simulations in revealing the mechanism of copolymer micelle self-assembly is discussed.

19.
BMC Pregnancy Childbirth ; 22(1): 231, 2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35317741

RESUMO

BACKGROUND: Surfactant protein D (SP-D) is a critical component of the innate immune system intrinsically linked to energy metabolism. However, the relationship of SP-D gene polymorphisms and gestational diabetes mellitus (GDM) remains unclear. In this study, we analyzed SP-D gene polymorphisms in GDM patients and nondiabetic controls and then determined the association of SP-D gene polymorphisms with GDM. METHODS: We examined a common genetic polymorphism located in the SP-D coding region (rs721917, Met31Thr) in GDM patients (n = 147) and healthy pregnant controls (n = 97) by using a cleaved amplification polymorphism sequence-tagged sites (PCR-RFLP) technique. The level of SP-D protein in the serum of GDM patients and nondiabetic controls was determined by ELISA. The gene and allele frequencies of SP-D and their association with GDM as well as SP-D protein levels were analyzed and expressed as odds ratios (ORs) with 95% confidence intervals (95% CIs). RESULTS: We found that there was a significant association of the SP-D polymorphism (rs721917) with GDM. The SP-D (T/T) genotype was found in 11.6% and 21.6% of GDM patients and matched healthy controls, respectively (odds ratio, 0.473; 95% confidence interval, 0.235-0.952; P = 0.033), indicating that women with the (T/T) genotype had a lower prevalence of GDM (OR = 0.473). Women with the T/C genotype showed an increased risk of GDM (odds ratio, 2.440; 95% confidence interval, 1.162-5.123; P = 0.017). We did not observe corrections between glucose homeostasis markers and SP-D genotypes in women with GDM. Furthermore, serum SP-D levels were higher in GDM patients than in matched healthy controls. CONCLUSIONS: This study found the first evidence that an SP-D gene polymorphism (rs721917) was associated with GDM, which may provide the basis for further study on how SP-D plays a regulatory role in GDM.


Assuntos
Diabetes Gestacional/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Proteína D Associada a Surfactante Pulmonar/genética , Adulto , Povo Asiático/genética , Estudos de Casos e Controles , Diabetes Gestacional/sangue , Feminino , Humanos , Gravidez , Proteína D Associada a Surfactante Pulmonar/sangue , Adulto Jovem
20.
Nano Lett ; 21(7): 2982-2988, 2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33792314

RESUMO

Directing nanoparticles into ordered organization in polymer matrix to improve macroscopic properties of nanocomposites remains a challenge. Herein, by means of theoretical simulations, we show the high permittivity of hybrid nanostructures designed with mixtures of AB block copolymer-grafted nanoparticles and lamella-forming AC diblock copolymers. The grafted nanoparticles self-assemble into parallel stripes or highly ordered networks in the lamellae of the AC diblock copolymers. The ordered nanoparticle networks, including honeycomb-like and kagomé networks, provide bending and conductive pathways for concentrating electric fields, which results in the improvement of the permittivity. We envisage that this strategy will open a gateway to prepare hierarchically ordered functional nanocomposites with distinctive dielectric properties.

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